WorldWideScience

Sample records for antigenic variation var

  1. Plasmodium falciparum antigenic variation. Mapping mosaic var gene sequences onto a network of shared, highly polymorphic sequence blocks.

    Science.gov (United States)

    Bull, Peter C; Buckee, Caroline O; Kyes, Sue; Kortok, Moses M; Thathy, Vandana; Guyah, Bernard; Stoute, José A; Newbold, Chris I; Marsh, Kevin

    2008-06-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a potentially important family of immune targets, encoded by an extremely diverse gene family called var. Understanding of the genetic organization of var genes is hampered by sequence mosaicism that results from a long history of non-homologous recombination. Here we have used software designed to analyse social networks to visualize the relationships between large collections of short var sequences tags sampled from clinical parasite isolates. In this approach, two sequences are connected if they share one or more highly polymorphic sequence blocks. The results show that the majority of analysed sequences including several var-like sequences from the chimpanzee parasite Plasmodium reichenowi can be either directly or indirectly linked together in a single unbroken network. However, the network is highly structured and contains putative subgroups of recombining sequences. The major subgroup contains the previously described group A var genes, previously proposed to be genetically distinct. Another subgroup contains sequences found to be associated with rosetting, a parasite virulence phenotype. The mosaic structure of the sequences and their division into subgroups may reflect the conflicting problems of maximizing antigenic diversity and minimizing epitope sharing between variants while maintaining their host cell binding functions.

  2. Generation of antigenic diversity in Plasmodium falciparum by structured rearrangement of Var genes during mitosis.

    Directory of Open Access Journals (Sweden)

    Antoine Claessens

    2014-12-01

    Full Text Available The most polymorphic gene family in P. falciparum is the ∼60 var genes distributed across parasite chromosomes, both in the subtelomeres and in internal regions. They encode hypervariable surface proteins known as P. falciparum erythrocyte membrane protein 1 (PfEMP1 that are critical for pathogenesis and immune evasion in Plasmodium falciparum. How var gene sequence diversity is generated is not currently completely understood. To address this, we constructed large clone trees and performed whole genome sequence analysis to study the generation of novel var gene sequences in asexually replicating parasites. While single nucleotide polymorphisms (SNPs were scattered across the genome, structural variants (deletions, duplications, translocations were focused in and around var genes, with considerable variation in frequency between strains. Analysis of more than 100 recombination events involving var exon 1 revealed that the average nucleotide sequence identity of two recombining exons was only 63% (range: 52.7-72.4% yet the crossovers were error-free and occurred in such a way that the resulting sequence was in frame and domain architecture was preserved. Var exon 1, which encodes the immunologically exposed part of the protein, recombined in up to 0.2% of infected erythrocytes in vitro per life cycle. The high rate of var exon 1 recombination indicates that millions of new antigenic structures could potentially be generated each day in a single infected individual. We propose a model whereby var gene sequence polymorphism is mainly generated during the asexual part of the life cycle.

  3. Antigenic Variation in Bacterial Pathogens.

    Science.gov (United States)

    Palmer, Guy H; Bankhead, Troy; Seifert, H Steven

    2016-02-01

    Antigenic variation is a strategy used by a broad diversity of microbial pathogens to persist within the mammalian host. Whereas viruses make use of a minimal proofreading capacity combined with large amounts of progeny to use random mutation for variant generation, antigenically variant bacteria have evolved mechanisms which use a stable genome, which aids in protecting the fitness of the progeny. Here, three well-characterized and highly antigenically variant bacterial pathogens are discussed: Anaplasma, Borrelia, and Neisseria. These three pathogens display a variety of mechanisms used to create the structural and antigenic variation needed for immune escape and long-term persistence. Intrahost antigenic variation is the focus; however, the role of these immune escape mechanisms at the population level is also presented.

  4. The effects of a partitioned var gene repertoire of Plasmodium falciparum on antigenic diversity and the acquisition of clinical immunity

    Directory of Open Access Journals (Sweden)

    Arinaminpathy Nimalan

    2008-01-01

    Full Text Available Abstract Background The human malaria parasite Plasmodium falciparum exploits antigenic diversity and within-host antigenic variation to evade the host's immune system. Of particular importance are the highly polymorphic var genes that encode the family of cell surface antigens PfEMP1 (Plasmodium falciparum Erythrocyte Membrane Protein 1. It has recently been shown that in spite of their extreme diversity, however, these genes fall into distinct groups according to chromosomal location or sequence similarity, and that recombination may be confined within these groups. Methods This study presents a mathematical analysis of how recombination hierarchies affect diversity, and, by using simple stochastic simulations, investigates how intra- and inter-genic diversity influence the rate at which individuals acquire clinical immunity. Results The analysis demonstrates that the partitioning of the var gene repertoire has a limiting effect on the total diversity attainable through recombination and that the limiting effect is strongly influenced by the respective sizes of each of the partitions. Furthermore, by associating expression of one of the groups with severe malaria it is demonstrated how a small number of infections can be sufficient to protect against disease despite a seemingly limitless number of possible non-identical repertoires. Conclusion Recombination hierarchies within the var gene repertoire of P. falciparum have a severe effect on strain diversity and the process of acquiring immunity against clinical malaria. Future studies will show how the existence of these recombining groups can offer an evolutionary advantage in spite of their restriction on diversity.

  5. Regulation of antigenic variation in Plasmodium falciparum: censoring freedom of expression?

    Science.gov (United States)

    Duffy, Michael F; Reeder, John C; Brown, Graham V

    2003-03-01

    Plasmodium falciparum employs a strategy of clonal antigenic variation to evade the host immune response during the intraerythrocytic stage of its life cycle. The major variant parasite molecule is the P. falciparum erythrocyte membrane protein (PfEMP)1, which is encoded by the var multigene family. The parasite switches between different PfEMP1 molecules through regulation of var transcription. Recent studies have shed considerable light on this process, but much remains unknown. However, striking parallels between transcriptional control of var and genes in other organisms provide direction for future studies.

  6. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

    Directory of Open Access Journals (Sweden)

    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  7. Novel adenovirus encoded virus-like particles displaying the placental malaria associated VAR2CSA antigen

    DEFF Research Database (Denmark)

    Andersson, Anne-Marie C; dos Santos Marques Resende, Mafalda; Salanti, Ali

    2017-01-01

    The malaria parasite Plasmodium falciparum presents antigens on the infected erythrocyte surface that bind human receptors expressed on the vascular endothelium. The VAR2CSA mediated binding to a distinct chondroitin sulphate A (CSA) is a crucial step in the pathophysiology of placental malaria a...

  8. Antigenic variation: Molecular and genetic mechanisms of relapsing disease

    Energy Technology Data Exchange (ETDEWEB)

    Cruse, J.M.; Lewis, R.E.

    1987-01-01

    This book contains 10 chapters. They are: Contemporary Concepts of Antigenic Variation; Antigenic Variation in the Influenza Viruses; Mechanisms of Escape of Visna Lentiviruses from Immunological Control; A Review of Antigenic Variation by the Equine Infectious Anemia Virus; Biologic and Molecular Variations in AIDS Retrovirus Isolates; Rabies Virus Infection: Genetic Mutations and the Impact on Viral Pathogenicity and Immunity; Immunobiology of Relapsing Fever; Antigenic Variation in African Trypanosomes; Antigenic Variation and Antigenic Diversity in Malaria; and Mechanisms of Immune Evasion in Schistosomiasis.

  9. A Novel Virus-Like Particle Based Vaccine Platform Displaying the Placental Malaria Antigen VAR2CSA.

    Directory of Open Access Journals (Sweden)

    Susan Thrane

    Full Text Available Placental malaria caused by Plasmodium falciparum is a major cause of mortality and severe morbidity. Clinical testing of a soluble protein-based vaccine containing the parasite ligand, VAR2CSA, has been initiated. VAR2CSA binds to the human receptor chondroitin sulphate A (CSA and is responsible for sequestration of Plasmodium falciparum infected erythrocytes in the placenta. It is imperative that a vaccine against malaria in pregnancy, if administered to women before they become pregnant, can induce a strong and long lasting immune response. While most soluble protein-based vaccines have failed during clinical testing, virus-like particle (VLP based vaccines (e.g., the licensed human papillomavirus vaccines have demonstrated high efficacy, suggesting that the spatial assembly of the vaccine antigen is a critical parameter for inducing an optimal long-lasting protective immune response. We have developed a VLP vaccine display platform by identifying regions of the HPV16 L1 coat protein where a biotin acceptor site (AviTagTM can be inserted without compromising VLP-assembly. Subsequent biotinylation of Avi-L1 VLPs allow us to anchor monovalent streptavidin (mSA-fused proteins to the biotin, thereby obtaining a dense and repetitive VLP-display of the vaccine antigen. The mSA-VAR2CSA antigen was delivered on the Avi-L1 VLP platform and tested in C57BL/6 mice in comparison to two soluble protein-based vaccines consisting of naked VAR2CSA and mSA-VAR2CSA. The mSA-VAR2CSA Avi-L1 VLP and soluble mSA-VAR2CSA vaccines induced higher antibody titers than the soluble naked VAR2CSA vaccine after three immunizations. The VAR2CSA Avi-L1 VLP vaccine induced statistically significantly higher endpoint titres compared to the soluble mSA-VAR2CSA vaccine, after 1st and 2nd immunization; however, this difference was not statistically significant after 3rd immunization. Importantly, the VLP-VAR2CSA induced antibodies were functional in inhibiting the binding of

  10. Antigenic variation of Streptococcus mutans colonizing gnotobiotic rats.

    Science.gov (United States)

    Bratthall, D; Gibbons, R J

    1975-12-01

    Strains of Streptococcus mutans representative of serotypes b and d exhibited antigenic variation in both the oral cavity and in the intestinal canal of gnotobiotic rats. Laboratory-maintained cultures did not vary. The antigenic alterations observed were: (i) loss of detectable levels of both weakly reacting "strain" antigens and the type antigen; (ii) decreased production of the type antigen; (ii) production of altered type antigen; and (iv) production of an antigen not possessed by the parent strain. Immunization of animals before monoinfection with S. mutans strain Bob-1 (serotype d) appeared to increase the rate of emergence of antigenically altered mutants in the intestinal canal, and more diversely altered isolates were obtained. Antigenic variation may account in part for the variation noted by several investigators in attempting to immunize animals against S. mutans-induced dental caries.

  11. Molecular players of homologous recombination in protozoan parasites: implications for generating antigenic variation.

    Science.gov (United States)

    Bhattacharyya, Mrinal Kanti; Norris, Douglas E; Kumar, Nirbhay

    2004-06-01

    A major impediment to vaccine development against infections caused by protozoan parasites such as Plasmodium falciparum and Trypanosoma is the extraordinary ability of these parasites to rapidly change their surface molecules, a phenomenon known as antigenic variation. A prominent determinant of antigenic variation in these organisms is associated with rearrangements of genes, especially those known as var in P. falciparum and vsg in Trypanosoma. However, mechanisms underlying generation of anitgenic diversities among these protozoan parasites are poorly understood. The hypothesis that links all the different sections in this review is that antigenic variations in the protozoan parasites is coupled with genetic rearrangements, which occur during the course of DNA break repair. Here, we provide comprehensive and up-to-date information on Rad51 in these organisms, an eukaryotic homologue of bacterial RecA, and homologous recombination mechanisms. In trypanosomes both Rad51-dependent and -independent mechanisms have been suggested to play roles in antigenic variation. Finally, we speculate on how might similar DNA repair mechanisms contribute to genetic rearrangement associated with antigenic variation in the apicomplexan Plasmodium parasites, an immune evasion strategy.

  12. Recruitment of PfSET2 by RNA polymerase II to variant antigen encoding loci contributes to antigenic variation in P. falciparum.

    Directory of Open Access Journals (Sweden)

    Uchechi E Ukaegbu

    2014-01-01

    Full Text Available Histone modifications are important regulators of gene expression in all eukaryotes. In Plasmodium falciparum, these epigenetic marks regulate expression of genes involved in several aspects of host-parasite interactions, including antigenic variation. While the identities and genomic positions of many histone modifications have now been cataloged, how they are targeted to defined genomic regions remains poorly understood. For example, how variant antigen encoding loci (var are targeted for deposition of unique histone marks is a mystery that continues to perplex the field. Here we describe the recruitment of an ortholog of the histone modifier SET2 to var genes through direct interactions with the C-terminal domain (CTD of RNA polymerase II. In higher eukaryotes, SET2 is a histone methyltransferase recruited by RNA pol II during mRNA transcription; however, the ortholog in P. falciparum (PfSET2 has an atypical architecture and its role in regulating transcription is unknown. Here we show that PfSET2 binds to the unphosphorylated form of the CTD, a property inconsistent with its recruitment during mRNA synthesis. Further, we show that H3K36me3, the epigenetic mark deposited by PfSET2, is enriched at both active and silent var gene loci, providing additional evidence that its recruitment is not associated with mRNA production. Over-expression of a dominant negative form of PfSET2 designed to disrupt binding to RNA pol II induced rapid var gene expression switching, confirming both the importance of PfSET2 in var gene regulation and a role for RNA pol II in its recruitment. RNA pol II is known to transcribe non-coding RNAs from both active and silent var genes, providing a possible mechanism by which it could recruit PfSET2 to var loci. This work unifies previous reports of histone modifications, the production of ncRNAs, and the promoter activity of var introns into a mechanism that contributes to antigenic variation by malaria parasites.

  13. Mosaic VSGs and the scale of Trypanosoma brucei antigenic variation.

    Directory of Open Access Journals (Sweden)

    James P J Hall

    Full Text Available A main determinant of prolonged Trypanosoma brucei infection and transmission and success of the parasite is the interplay between host acquired immunity and antigenic variation of the parasite variant surface glycoprotein (VSG coat. About 0.1% of trypanosome divisions produce a switch to a different VSG through differential expression of an archive of hundreds of silent VSG genes and pseudogenes, but the patterns and extent of the trypanosome diversity phenotype, particularly in chronic infection, are unclear. We applied longitudinal VSG cDNA sequencing to estimate variant richness and test whether pseudogenes contribute to antigenic variation. We show that individual growth peaks can contain at least 15 distinct variants, are estimated computationally to comprise many more, and that antigenically distinct 'mosaic' VSGs arise from segmental gene conversion between donor VSG genes or pseudogenes. The potential for trypanosome antigenic variation is probably much greater than VSG archive size; mosaic VSGs are core to antigenic variation and chronic infection.

  14. Intraspecific Variation in Carotenoids of Brassica oleracea var. sabellica.

    Science.gov (United States)

    Mageney, Vera; Baldermann, Susanne; Albach, Dirk C

    2016-04-27

    Carotenoids are best known as a source of natural antioxidants. Physiologically, carotenoids are part of the photoprotection in plants as they act as scavengers of reactive oxygen species (ROS). An important source of carotenoids in European food is Brassica oleracea. Focusing on the most abundant carotenoids, we estimated the contents of ß-carotene, (9Z)-neoxanthin, zeaxanthin, and lutein as well as those of chlorophylls a and b to assess their variability in Brassica oleracea var. sabellica. Our analyses included more than 30 cultivars categorized in five distinct sets grouped according to morphological characteristics or geographical origin. Our results demonstrated specific carotenoid patterns characteristic for American, Italian, and red-colored kale cultivars. Moreover, we demonstrated a tendency of high zeaxanthin proportions under traditional harvest conditions, which accord to low-temperature regimes. We also compared the carotenoid patterns of self-generated hybrid lines. Corresponding findings indicated that crossbreeding has a high potential for carotenoid content optimization in kale.

  15. Antigenic variation with a twist--the Borrelia story.

    Science.gov (United States)

    Norris, Steven J

    2006-06-01

    A common mechanism of immune evasion in pathogenic bacteria and protozoa is antigenic variation, in which genetic or epigenetic changes result in rapid, sequential shifts in a surface-exposed antigen. In this issue of Molecular Microbiology, Dai et al. provide the most complete description to date of the vlp/vsp antigenic variation system of the relapsing fever spirochaete, Borrelia hermsii. This elaborate, plasmid-encoded system involves an expression site that can acquire either variable large protein (vlp) or variable small protein (vsp) surface lipoprotein genes from 59 different archival copies. The archival vlp and vsp genes are arranged in clusters on at least five different plasmids. Gene conversion occurs through recombination events at upstream homology sequences (UHS) found in each gene copy, and at downstream homology sequences (DHS) found periodically among the vlp/vsp archival genes. Previous studies have shown that antigenic variation in relapsing fever Borrelia not only permits the evasion of host antibody responses, but can also result in changes in neurotropism and other pathogenic properties. The vlsE antigenic variation locus of Lyme disease spirochaetes, although similar in sequence to the relapsing fever vlp genes, has evolved a completely different antigenic variation mechanism involving segmental recombination from a contiguous array of vls silent cassettes. These two systems thus appear to represent divergence from a common precursor followed by functional convergence to create two distinct antigenic variation processes.

  16. Use of in vivo-regulated promoters to deliver antigens from attenuated Salmonella enterica var. Typhimurium.

    Science.gov (United States)

    Dunstan, S J; Simmons, C P; Strugnell, R A

    1999-10-01

    This study describes the construction and analysis of three in vivo-inducible promoter expression plasmids, containing pnirB, ppagC, and pkatG, for the delivery of foreign antigens in the DeltaaroAD mutant of Salmonella enterica var. Typhimurium (hereafter referred to as S. typhimurium). The reporter genes encoding beta-galactosidase and firefly luciferase were used to assess the comparative levels of promoter activity in S. typhimurium in vitro in response to different induction stimuli and in vivo in immunized mice. It was determined that the ppagC construct directed the expression of more beta-galactosidase and luciferase in S. typhimurium than the pnirB and pkatG constructs, both in vitro and in vivo. The gene encoding the C fragment of tetanus toxin was expressed in the aroAD mutant of S. typhimurium (BRD509) under the control of the three promoters. Mice orally immunized with attenuated S. typhimurium expressing C fragment under control of the pagC promoter [BRD509(pKK/ppagC/C frag)] mounted the highest tetanus toxoid-specific serum antibody response. Levels of luciferase expression in vivo and C-fragment expression in vitro from the pagC promoter appeared to be equivalent to if not lower than the levels of expression detected with the constitutive trc promoter. However, mice immunized with BRD509(pKK/ppagC/C frag) induced significantly higher levels of tetanus toxoid-specific antibody than BRD509(pKK/C frag)-immunized mice, suggesting that the specific location of foreign antigen expression may be important for immunogenicity. Mutagenesis of the ribosome binding sites (RBS) in the three promoter/C fragment expression plasmids was also performed. Despite optimization of the RBS in the three different promoter elements, the expression levels in vivo and overall immunogenicity of C fragment when delivered to mice by attenuated S. typhimurium were not affected. These studies suggest that in vivo-inducible promoters may give rise to enhanced immunogenicity and

  17. Antigenic variation in Plasmodium falciparum malaria involves a highly structured switching pattern.

    Directory of Open Access Journals (Sweden)

    Mario Recker

    2011-03-01

    Full Text Available Many pathogenic bacteria, fungi, and protozoa achieve chronic infection through an immune evasion strategy known as antigenic variation. In the human malaria parasite Plasmodium falciparum, this involves transcriptional switching among members of the var gene family, causing parasites with different antigenic and phenotypic characteristics to appear at different times within a population. Here we use a genome-wide approach to explore this process in vitro within a set of cloned parasite populations. Our analyses reveal a non-random, highly structured switch pathway where an initially dominant transcript switches via a set of switch-intermediates either to a new dominant transcript, or back to the original. We show that this specific pathway can arise through an evolutionary conflict in which the pathogen has to optimise between safeguarding its limited antigenic repertoire and remaining capable of establishing infections in non-naïve individuals. Our results thus demonstrate a crucial role for structured switching during the early phases of infections and provide a unifying theory of antigenic variation in P. falciparum malaria as a balanced process of parasite-intrinsic switching and immune-mediated selection.

  18. ViVar: a comprehensive platform for the analysis and visualization of structural genomic variation.

    Science.gov (United States)

    Sante, Tom; Vergult, Sarah; Volders, Pieter-Jan; Kloosterman, Wigard P; Trooskens, Geert; De Preter, Katleen; Dheedene, Annelies; Speleman, Frank; De Meyer, Tim; Menten, Björn

    2014-01-01

    Structural genomic variations play an important role in human disease and phenotypic diversity. With the rise of high-throughput sequencing tools, mate-pair/paired-end/single-read sequencing has become an important technique for the detection and exploration of structural variation. Several analysis tools exist to handle different parts and aspects of such sequencing based structural variation analyses pipelines. A comprehensive analysis platform to handle all steps, from processing the sequencing data, to the discovery and visualization of structural variants, is missing. The ViVar platform is built to handle the discovery of structural variants, from Depth Of Coverage analysis, aberrant read pair clustering to split read analysis. ViVar provides you with powerful visualization options, enables easy reporting of results and better usability and data management. The platform facilitates the processing, analysis and visualization, of structural variation based on massive parallel sequencing data, enabling the rapid identification of disease loci or genes. ViVar allows you to scale your analysis with your work load over multiple (cloud) servers, has user access control to keep your data safe and is easy expandable as analysis techniques advance. URL: https://www.cmgg.be/vivar/

  19. ViVar: a comprehensive platform for the analysis and visualization of structural genomic variation.

    Directory of Open Access Journals (Sweden)

    Tom Sante

    Full Text Available Structural genomic variations play an important role in human disease and phenotypic diversity. With the rise of high-throughput sequencing tools, mate-pair/paired-end/single-read sequencing has become an important technique for the detection and exploration of structural variation. Several analysis tools exist to handle different parts and aspects of such sequencing based structural variation analyses pipelines. A comprehensive analysis platform to handle all steps, from processing the sequencing data, to the discovery and visualization of structural variants, is missing. The ViVar platform is built to handle the discovery of structural variants, from Depth Of Coverage analysis, aberrant read pair clustering to split read analysis. ViVar provides you with powerful visualization options, enables easy reporting of results and better usability and data management. The platform facilitates the processing, analysis and visualization, of structural variation based on massive parallel sequencing data, enabling the rapid identification of disease loci or genes. ViVar allows you to scale your analysis with your work load over multiple (cloud servers, has user access control to keep your data safe and is easy expandable as analysis techniques advance. URL: https://www.cmgg.be/vivar/

  20. Microbial antigenic variation mediated by homologous DNA recombination

    OpenAIRE

    2012-01-01

    Pathogenic microorganisms employ numerous molecular strategies in order to delay or circumvent recognition by the immune system of their host. One of the most widely used strategies of immune evasion is antigenic variation, in which immunogenic molecules expressed on the surface of a microorganism are continuously modified. As a consequence, the host is forced to constantly adapt its humoral immune response against this pathogen. An antigenic change thus provides the microorganism with an opp...

  1. Limited antigenic variation in the Trypanosoma cruzi candidate vaccine antigen TSA-1.

    Science.gov (United States)

    Knight, J M; Zingales, B; Bottazzi, M E; Hotez, P; Zhan, B

    2014-12-01

    Chagas disease (American trypanosomiasis caused by Trypanosoma cruzi) is one of the most important neglected tropical diseases in the Western Hemisphere. The toxicities and limited efficacies of current antitrypanosomal drugs have prompted a search for alternative technologies such as a therapeutic vaccine comprised of T. cruzi antigens, including a recombinant antigen encoding the N-terminal 65 kDa portion of Trypomastigote surface antigen-1 (TSA-1). With at least six known genetically distinct T. cruzi lineages, variability between the different lineages poses a unique challenge for the development of broadly effective therapeutic vaccine. The variability across the major lineages in the current vaccine candidate antigen TSA-1 has not previously been addressed. To assess the variation in TSA-1, we cloned and sequenced TSA-1 from several different T. cruzi strains representing three of the most clinically relevant lineages. Analysis of the different alleles showed limited variation in TSA-1 across the different strains and fit with the current theory for the evolution of the different lineages. Additionally, minimal variation in known antigenic epitopes for the HLA-A 02 allele suggests that interlineage variation in TSA-1 would not impair the range and efficacy of a vaccine containing TSA-1.

  2. Production and Characterization of a Monoclonal Antibody Raised Against Surface Antigens from Mycelium of Gaeumannomyces graminis var. tritici: Evidence for an Extracellular Polyphenol Oxidase.

    Science.gov (United States)

    Thornton, C R; Dewey, F M; Gilligan, C A

    1997-01-01

    ABSTRACT A murine monoclonal antibody (MAb) of immunoglobulin class M (IgM) was raised against surface antigens from Gaeumannomyces graminis var. tritici and, by enzyme-linked immunosorbent assay, recognized isolates of G. graminis var. tritici, G. graminis var. avenae and G. graminis var. graminis. Characterization of the antigen by heat and protease treatments showed that the epitope recognized by the MAb was a protein. Antigen production was detected only in live mycelia. Immunofluorescence studies showed that the antigen was associated with both the broad melanized macrohyphae and hyaline mycelia of G. graminis var. tritici. Secretion of antigen into an aqueous minimal medium was promoted only by exposure of live mycelia to certain phenolic substrates, including monophenols ortho-, para-, and meta-cresol; 3,4,5-trihydroxybenzoic acid (gallic acid); and phenolic amino acid L-3-(3,4-dihydroxyphenyl) alanine (L-DOPA). Antigen secretion was not promoted by 3-(4-hydroxyphenyl) alanine (L-tyrosine). The MAb reacted strongly with purified enzyme laccase (polyphenol oxidase, EC 1.10.3.2) but did not recognize purified tyrosinase (monophenol oxidase, EC 1.14.18.1). Moreover, chemicals that bind to copper and inhibit copper-containing enzymes such as laccase completely inhibited antigen secretion in response to L-DOPA. The MAb was tested for specificity against a wide range of fungi, common yeast species, and gram positive and negative bacteria. It did not recognize antigens from a broad range of unrelated fungi, including Gliocladium roseum, Fusarium sp., Phoma exigua, Phialophora fastigiata, Penicillium crustosum, Pythium ultimum, Rhizopus stolonifer, Rhizoctonia carotae, R. oryzae, R. tuliparum, and Trichoderma viride, nor did it recognize surface antigens from yeasts or bacteria. The MAb cross-reacted with antigens from Botrytis spp., Chaetomium globosum, R. cerealis, and R. solani. However, secretion of antigen by R. solani and R. cerealis was not promoted by L

  3. Microbial antigenic variation mediated by homologous DNA recombination

    NARCIS (Netherlands)

    C. Vink (Cornelis); L. Rudenko (Larisa); H.S. Seifert (H. Steven)

    2012-01-01

    textabstractPathogenic microorganisms employ numerous molecular strategies in order to delay or circumvent recognition by the immune system of their host. One of the most widely used strategies of immune evasion is antigenic variation, in which immunogenic molecules expressed on the surface of a mic

  4. VarB Plus: An Integrated Tool for Visualization of Genome Variation Datasets

    KAUST Repository

    Hidayah, Lailatul

    2012-07-01

    Research on genomic sequences has been improving significantly as more advanced technology for sequencing has been developed. This opens enormous opportunities for sequence analysis. Various analytical tools have been built for purposes such as sequence assembly, read alignments, genome browsing, comparative genomics, and visualization. From the visualization perspective, there is an increasing trend towards use of large-scale computation. However, more than power is required to produce an informative image. This is a challenge that we address by providing several ways of representing biological data in order to advance the inference endeavors of biologists. This thesis focuses on visualization of variations found in genomic sequences. We develop several visualization functions and embed them in an existing variation visualization tool as extensions. The tool we improved is named VarB, hence the nomenclature for our enhancement is VarB Plus. To the best of our knowledge, besides VarB, there is no tool that provides the capability of dynamic visualization of genome variation datasets as well as statistical analysis. Dynamic visualization allows users to toggle different parameters on and off and see the results on the fly. The statistical analysis includes Fixation Index, Relative Variant Density, and Tajima’s D. Hence we focused our efforts on this tool. The scope of our work includes plots of per-base genome coverage, Principal Coordinate Analysis (PCoA), integration with a read alignment viewer named LookSeq, and visualization of geo-biological data. In addition to description of embedded functionalities, significance, and limitations, future improvements are discussed. The result is four extensions embedded successfully in the original tool, which is built on the Qt framework in C++. Hence it is portable to numerous platforms. Our extensions have shown acceptable execution time in a beta testing with various high-volume published datasets, as well as positive

  5. Seasonal Variation in Essential oil Composition of Artemisianilagirica var. septentrionalis from Foot Hills of Western Himalaya

    Directory of Open Access Journals (Sweden)

    Rajendra Chandra Padalia

    2014-05-01

    Full Text Available Essential oils composition of the aerial parts of Artemisia nilagirica (Clarke Pamp. var. septentrionalis Pamp. in different seasons viz. spring, summer, rainy, autumn and winter seasons under foot hills agroclimatic conditions of western Himalaya were analyzed and compared by GC–FID and GC–MS. Essential oils were mainly composed of monoterpenoids (59.0%-77.3% and sesquiterpenoids (15.7%-31.6%. The major constituents identified were artemisia ketone (38.3%-61.2%, chrysanthenone (1.5%-7.7%, germacrene D (3.1%-6.8%, β-caryophyllene (1.9%-6.8%, germacra-4,5,10-trien-1-α-ol (1.9%-4.9% and artemisia alcohol (1.4%-3.6%. Compositional analysis showed significant variations in the terpenoid compositions due to seasonal variations. Further, this is for the first time the seasonal variations in essential oil compositions of artemisia ketone rich chemotype of A. nilagirica var. septentrionalis is being reported from India.

  6. Genetic diversity and antigenicity variation of Babesia bovis merozoite surface antigen-1 (MSA-1) in Thailand.

    Science.gov (United States)

    Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki

    2016-07-01

    Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our phylogenetic analysis, Thai msa-1 gene sequences occurred in 18 clades; seven among them were composed of sequences exclusively from Thailand. To investigate differential antigenicity of isolated MSA-1 proteins, we expressed and purified eight recombinant MSA-1 (rMSA-1) proteins, including an rMSA-1 from B. bovis Texas (T2Bo) strain and seven rMSA-1 proteins based on the Thai msa-1 sequences. When these antigens were analyzed in a western blot assay, anti-T2Bo cattle serum strongly reacted with the rMSA-1 from T2Bo, as well as with three other rMSA-1 proteins that shared 54.9-68.4% sequence similarity with T2Bo MSA-1. In contrast, no or weak reactivity was observed for the remaining rMSA-1 proteins, which shared low sequence similarity (35.0-39.7%) with T2Bo MSA-1. While demonstrating the high genetic diversity of the B. bovis msa-1 gene in Thailand, the present findings suggest that the genetic diversity results in antigenicity variations among the MSA-1 antigens of B. bovis in Thailand.

  7. Antigenic variation in trypanosomes: enhanced phenotypic variation in a eukaryotic parasite.

    Science.gov (United States)

    Barry, J D; McCulloch, R

    2001-01-01

    African trypanosomes are unicellular, eukaryotic parasites that live extracellularly in a wide range of mammals, including humans. They have a surface coat, composed of variant surface glycoprotein (VSG), which probably is essential and acts as a defence against general innate immunity and against acquired immunity directed at invariant surface antigens. In effect, the VSG is the only antigen that the host can target, and each trypanosome expresses only one VSG. To counter specific antibodies against the VSG, trypanosomes periodically undergo antigenic variation, the change to expression of another VSG. Antigenic variation belongs to the general survival strategy of enhanced phenotypic variation, where a subset of 'contingency' genes of viruses, bacteria and parasites hypermutate, allowing rapid adaptation to hostile or changing environments. A fundamental feature of antigenic variation is its link with the population dynamics of trypanosomes within the single host. Antigenic variants appear hierarchically within the mammalian host, with a mixture of order and randomness. The underlying mechanisms of this are not understood, although differential VSG gene activation may play a prominent part. Trypanosome antigenic variation has evolved a second arm in which the infective metacyclic population in the tsetse fly expresses a defined mixture of VSGs, although again each trypanosome expresses a single VSG. Differential VSG expression enhances transmission to new hosts, in the case of bloodstream trypanosomes by prolonging infection, and in the metacyclic population by generating diversity that may counter existing partial immunity in reservoir hosts. Antigenic variation employs a huge repertoire of VSG genes. Only one is expressed at a time in bloodstream trypanosomes, as a result of transcription being restricted to a set of about 20 bloodstream expression sites (BESs), which are at chromosome telomeres. Only one BES is active at a time, probably through

  8. Insight into Antigenic Diversity of VAR2CSA-DBL5 epsilon Domain from Multiple Plasmodium falciparum Placental Isolates

    DEFF Research Database (Denmark)

    Gnidehou, Sedami; Jessen, Leon Ivar; Gangnard, Stephane

    2010-01-01

    Background: Protection against pregnancy associated malaria (PAM) is associated with high levels of anti-VAR2CSA antibodies. This protection is obtained by the parity dependent acquisition of anti-VAR2CSA antibodies. Distinct parity-associated molecular signatures have been identified in VAR2CSA ...

  9. The Plasmodium falciparum STEVOR multigene family mediates antigenic variation of the infected erythrocyte.

    Directory of Open Access Journals (Sweden)

    Makhtar Niang

    2009-02-01

    Full Text Available Modifications of the Plasmodium falciparum-infected red blood cell (iRBC surface have been linked to parasite-associated pathology. Such modifications enable the parasite to establish long-lasting chronic infection by evading antibody mediate immune recognition and splenic clearance. With the exception of the well-demonstrated roles of var-encoded PfEMP1 in virulence and immune evasion, the biological significance of other variant surface antigens (rif and stevor is largely unknown. While PfEMP1 and RIFIN have been located on the iRBC surface, recent studies have located STEVOR at the iRBC membrane where it may be exposed on the erythrocyte surface. To investigate the role of STEVOR in more detail, we have developed antibodies against two putative STEVOR proteins and used a combination of indirect immunofluorescence assays (IFA, live IFA, flow cytometry, as well as agglutination assays, which enable us to demonstrate that STEVOR is clonally variant at the surface of schizont stage parasites. Crucially, expression of different STEVOR on the surface of the iRBC changes the antigenic property of the parasite. Taken together, our data for the first time demonstrate that STEVOR plays a role in creating antigenic diversity of schizont stage parasites, thereby adding additional complexity to the immunogenic properties of the iRBC. Furthermore, it clearly demonstrates that to obtain a complete understanding of how parasite-induced pathology is linked to variation on the surface of the iRBC, focusing the interactions of multiple multigene families needs to be considered.

  10. Genetic variation and significance of hepatitis B surface antigen

    Directory of Open Access Journals (Sweden)

    ZHANG Zhenhua

    2013-11-01

    Full Text Available Hepatitis B virus (HBV is prone to genetic variation because there is reverse transcription in the process of HBV replication. The gene mutation of hepatitis B surface antigen may affect clinical diagnosis of HBV infection, viral replication, and vaccine effect. The current research and existing problems are discussed from the following aspects: the mechanism and biological and clinical significance of S gene mutation. Most previous studies focused on S gene alone, so S gene should be considered as part of HBV DNA in the future research on S gene mutation.

  11. Immunogenetic mechanisms driving norovirus GII.4 antigenic variation.

    Directory of Open Access Journals (Sweden)

    Lisa C Lindesmith

    Full Text Available Noroviruses are the principal cause of epidemic gastroenteritis worldwide with GII.4 strains accounting for 80% of infections. The major capsid protein of GII.4 strains is evolving rapidly, resulting in new epidemic strains with altered antigenic potentials. To test if antigenic drift may contribute to GII.4 persistence, human memory B cells were immortalized and the resulting human monoclonal antibodies (mAbs characterized for reactivity to a panel of time-ordered GII.4 virus-like particles (VLPs. Reflecting the complex exposure history of the volunteer, human anti-GII.4 mAbs grouped into three VLP reactivity patterns; ancestral (1987-1997, contemporary (2004-2009, and broad (1987-2009. NVB 114 reacted exclusively to the earliest GII.4 VLPs by EIA and blockade. NVB 97 specifically bound and blocked only contemporary GII.4 VLPs, while NBV 111 and 43.9 exclusively reacted with and blocked variants of the GII.4.2006 Minerva strain. Three mAbs had broad GII.4 reactivity. Two, NVB 37.10 and 61.3, also detected other genogroup II VLPs by EIA but did not block any VLP interactions with carbohydrate ligands. NVB 71.4 cross-neutralized the panel of time-ordered GII.4 VLPs, as measured by VLP-carbohydrate blockade assays. Using mutant VLPs designed to alter predicted antigenic epitopes, two evolving, GII.4-specific, blockade epitopes were mapped. Amino acids 294-298 and 368-372 were required for binding NVB 114, 111 and 43.9 mAbs. Amino acids 393-395 were essential for binding NVB 97, supporting earlier correlations between antibody blockade escape and carbohydrate binding variation. These data inform VLP vaccine design, provide a strategy for expanding the cross-blockade potential of chimeric VLP vaccines, and identify an antibody with broadly neutralizing therapeutic potential for the treatment of human disease. Moreover, these data support the hypothesis that GII.4 norovirus evolution is heavily influenced by antigenic variation of neutralizing

  12. A Plasmodium falciparum histone deacetylase regulates antigenic variation and gametocyte conversion.

    Science.gov (United States)

    Coleman, Bradley I; Skillman, Kristen M; Jiang, Rays H Y; Childs, Lauren M; Altenhofen, Lindsey M; Ganter, Markus; Leung, Yvette; Goldowitz, Ilana; Kafsack, Björn F C; Marti, Matthias; Llinás, Manuel; Buckee, Caroline O; Duraisingh, Manoj T

    2014-08-13

    The asexual forms of the malaria parasite Plasmodium falciparum are adapted for chronic persistence in human red blood cells, continuously evading host immunity using epigenetically regulated antigenic variation of virulence-associated genes. Parasite survival on a population level also requires differentiation into sexual forms, an obligatory step for further human transmission. We reveal that the essential nuclear gene, P. falciparum histone deacetylase 2 (PfHda2), is a global silencer of virulence gene expression and controls the frequency of switching from the asexual cycle to sexual development. PfHda2 depletion leads to dysregulated expression of both virulence-associated var genes and PfAP2-g, a transcription factor controlling sexual conversion, and is accompanied by increases in gametocytogenesis. Mathematical modeling further indicates that PfHda2 has likely evolved to optimize the parasite's infectious period by achieving low frequencies of virulence gene expression switching and sexual conversion. This common regulation of cellular transcriptional programs mechanistically links parasite transmissibility and virulence.

  13. A novel virus-like particle based vaccine platform displaying the placental malaria antigen VAR2CSA

    DEFF Research Database (Denmark)

    Thrane, Susan; Janitzek, Christoph M; Agerbæk, Mette Ø

    2015-01-01

    Placental malaria caused by Plasmodium falciparum is a major cause of mortality and severe morbidity. Clinical testing of a soluble protein-based vaccine containing the parasite ligand, VAR2CSA, has been initiated. VAR2CSA binds to the human receptor chondroitin sulphate A (CSA) and is responsibl...

  14. Antisense long noncoding RNAs regulate var gene activation in the malaria parasite Plasmodium falciparum.

    Science.gov (United States)

    Amit-Avraham, Inbar; Pozner, Guy; Eshar, Shiri; Fastman, Yair; Kolevzon, Netanel; Yavin, Eylon; Dzikowski, Ron

    2015-03-03

    The virulence of Plasmodium falciparum, the causative agent of the deadliest form of human malaria, is attributed to its ability to evade human immunity through antigenic variation. These parasites alternate between expression of variable antigens, encoded by members of a multicopy gene family named var. Immune evasion through antigenic variation depends on tight regulation of var gene expression, ensuring that only a single var gene is expressed at a time while the rest of the family is maintained transcriptionally silent. Understanding how a single gene is chosen for activation is critical for understanding mutually exclusive expression but remains a mystery. Here, we show that antisense long noncoding RNAs (lncRNAs) initiating from var introns are associated with the single active var gene at the time in the cell cycle when the single var upstream promoter is active. We demonstrate that these antisense transcripts are incorporated into chromatin, and that expression of these antisense lncRNAs in trans triggers activation of a silent var gene in a sequence- and dose-dependent manner. On the other hand, interference with these lncRNAs using complement peptide nucleic acid molecules down-regulated the active var gene, erased the epigenetic memory, and induced expression switching. Altogether, our data provide evidence that these antisense lncRNAs play a key role in regulating var gene activation and mutually exclusive expression.

  15. Gene Silencing and Antigenic Variation in Malaria Parasites

    Directory of Open Access Journals (Sweden)

    Kirk W. Deitsch

    2001-01-01

    Full Text Available Malaria remains one of the most important infectious diseases in the world today, infecting 300 to 500 million people yearly and resulting in 1 to 2 million deaths, primarily of young African children[1]. The most severe form of this disease is caused by infection with the mosquito borne protozoan parasite Plasmodium falciparum. This parasite lives by invading and multiplying within the red blood cells of its host, causing disease through anemia resulting from red cell destruction, and also through modifications made to the surface of infected red cells. These modifications make infected cells cytoadherent or “sticky”, allowing them to adhere to the walls of blood vessels, leading to obstruction of blood flow and such clinical manifestations as the often fatal syndrome of cerebral malaria[2]. In addition, parasites are capable of undergoing antigenic variation, a process of continually changing the identity of proteins on the surface of infected cells and thus avoiding the immune response mounted by the host[3]. This process promotes a long term, persistent infection that is difficult to clear.

  16. Evaluation of genotypic variation of broccoli (brassica oleracea var. italic) in response to selenium treatment

    Science.gov (United States)

    Broccoli (Brassica oleracea var. italic) fortified with selenium (Se) has been promoted as a functional food. Here we evaluated 38 broccoli accessions for their capacity to accumulate Se and for their responses to selenate treatment in terms of nutritional qualities and sulfur gene expression. We fo...

  17. Genetic Variation of the Endangered Gentiana lutea L. var. aurantiaca (Gentianaceae in Populations from the Northwest Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Oscar González-López

    2014-06-01

    Full Text Available Gentiana lutea L. (G. lutea L. is an endangered plant, patchily distributed along the mountains of Central and Southern Europe. In this study, inter-simple sequence repeat (ISSR markers were used to investigate the genetic variation in this species within and among populations of G. lutea L. var. aurantiaca of the Cantabrian Mountains (Northwest Iberian Peninsula. Samples of G. lutea L. collected at different locations of the Pyrenees and samples of G. lutea L. subsp. vardjanii of the Dolomites Alps were also analyzed for comparison. Using nine ISSR primers, 106 bands were generated, and 89.6% of those were polymorphic. The populations from the Northwest Iberian Peninsula were clustered in three different groups, with a significant correlation between genetic and geographic distances. Gentiana lutea L. var. aurantiaca showed 19.8% private loci and demonstrated a remarkable level of genetic variation, both among populations and within populations; those populations with the highest level of isolation show the lowest genetic variation within populations. The low number of individuals, as well as the observed genetic structure of the analyzed populations makes it necessary to protect them to ensure their survival before they are too small to persist naturally.

  18. Mini-review: Strategies for Variation and Evolution of Bacterial Antigens

    Science.gov (United States)

    Foley, Janet

    2015-01-01

    Across the eubacteria, antigenic variation has emerged as a strategy to evade host immunity. However, phenotypic variation in some of these antigens also allows the bacteria to exploit variable host niches as well. The specific mechanisms are not shared-derived characters although there is considerable convergent evolution and numerous commonalities reflecting considerations of natural selection and biochemical restraints. Unlike in viruses, mechanisms of antigenic variation in most bacteria involve larger DNA movement such as gene conversion or DNA rearrangement, although some antigens vary due to point mutations or modified transcriptional regulation. The convergent evolution that promotes antigenic variation integrates various evolutionary forces: these include mutations underlying variant production; drift which could remove alleles especially early in infection or during life history phases in arthropod vectors (when the bacterial population size goes through a bottleneck); selection not only for any particular variant but also for the mechanism for the production of variants (i.e., selection for mutability); and overcoming negative selection against variant production. This review highlights the complexities of drivers of antigenic variation, in particular extending evaluation beyond the commonly cited theory of immune evasion. A deeper understanding of the diversity of purpose and mechanisms of antigenic variation in bacteria will contribute to greater insight into bacterial pathogenesis, ecology and coevolution with hosts. PMID:26288700

  19. “Nothing is permanent but change”* -- Antigenic variation in persistent bacterial pathogens

    OpenAIRE

    Palmer, Guy H.; Bankhead, Troy; Lukehart, Sheila A.

    2009-01-01

    Pathogens persist in immunocompetent mammalian hosts using various strategies, including evasion of immune effectors by antigenic variation. Among highly antigenically variant bacteria, gene conversion is used to generate novel expressed variants from otherwise silent donor sequences. Recombination using oligonucleotide segments from multiple donors is a combinatorial mechanism that tremendously expands the variant repertoire, allowing thousands of variants to be generated from a relatively s...

  20. Antigenic variation and the genetics and epigenetics of the PfEMP1 erythrocyte surface antigens in Plasmodium falciparum malaria

    DEFF Research Database (Denmark)

    Arnot, David E; Jensen, Anja T R

    2011-01-01

    do become immune to P. falciparum malaria, but this is a slow process requiring multiple disease episodes which many, particularly young children, do not survive. Adult survivors are immune to the symptoms of malaria, and unless pregnant, can control the growth of most or all new inoculations....... Sterile immunity is not achieved and chronic parasitization of apparently healthy adults is the norm. In this article, we analyse the best understood malaria "antigenic variation" system, that based on Plasmodium falciparum's PfEMP1-type cytoadhesion antigens, and critically review recent literature...

  1. Global analysis of a class of HIV models with immune response and antigenic variation

    CERN Document Server

    Souza, Max O

    2008-01-01

    We study the global stability of two models for the HIV virus dynamics, that take into account the CTL immune response and antigenic variation. We show that both models are globally asymptotically stable, by using appropriate Lyapunov functions. For both models, we characterise the stable equilibrium points for the entire biologically relevant parameter range. In the model with antigenic variation, which can have a large number of equilibrium points, this allows us to determine what is the diversity of the persistent strains.

  2. Biological variation of total prostate-specific antigen

    DEFF Research Database (Denmark)

    Söletormos, Georg; Semjonow, Axel; Sibley, Paul E C

    2005-01-01

    , and estimates for the biological variation of tPSA could be derived from 12 of these studies. RESULTS: The mean biological variation was 20% in the concentration range 0.1-20 microg/L for men over 50 years. The biological variation means that the one-sided 95% confidence interval (CI) of the dispersion...

  3. Biogeographic variation of foliar n-alkanes of Juniperus communis var. saxatilis Pallas from the Balkans.

    Science.gov (United States)

    Rajčević, Nemanja; Janaćković, Pedja; Dodoš, Tanja; Tešević, Vele; Marin, Petar D

    2014-12-01

    The composition of the epicuticular n-alkanes isolated from the leaves of ten populations of Juniperus communis L. var. saxatilis Pallas from central (continental) and western (coastal) areas of the Balkan Peninsula was characterized by GC-FID and GC/MS analyses. In the leaf waxes, 14 n-alkane homologues with chain-lengths ranging from C22 to C35 were identified. All samples were dominated by n-tritriacontane (C33 ), but differences in two other dominant n-alkanes allowed separating the coastal from the continental populations. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses as well as the Mantel test) were deployed to analyze the diversity and variability of the epicuticular-leaf-n-alkane patterns of the ten natural populations of J. communis var. saxatilis and their relation to different geographic and bioclimatic parameters. Cluster analysis showed a high correlation of the leaf-n-alkane patterns with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon. Several bioclimatic parameters related to aridity were highly correlated with this differentiation. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

  4. Chemical variability and biological activities of Brassica rapa var. rapifera parts essential oils depending on geographic variation and extraction technique.

    Science.gov (United States)

    Saka, Boualem; Djouahri, Abderrahmane; Djerrad, Zineb; Souhila, Terfi; Aberrane, Sihem; Sabaou, Nasserdine; Baaliouamer, Aoumeur; Boudarene, Lynda

    2017-02-01

    In the present work, the Brassica rapa var. rapifera parts essential oils and their antioxidant and antimicrobial activities were investigated for the first time depending on geographic origin and extraction technique. GC and GC-MS analyses showed several constituents, including alcohols, aldehydes, esters, ketones, norisoprenoids, terpenic, nitrogen and sulphur compounds, totalizing 38 and 41 compounds in leaves and root essential oils, respectively. Nitrogen compounds were the main volatiles in leaves essential oils and sulphur compounds were the main volatiles in root essential oils. Qualitative and quantitative differences were found among B. rapa var. rapifera parts essential oils collected from different locations and extracted by hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) techniques. Furthermore, our findings showed a high variability for both antioxidant and antimicrobial activities. The highlighted variability reflects the high impact of plant part, geographic variation and extraction technique on chemical composition and biological activities, which led to conclude that we should select essential oils to be investigated carefully depending on these factors, in order to isolate the bioactive components or to have the best quality of essential oil in terms of biological activities and preventive effects in food. This article is protected by copyright. All rights reserved.

  5. Data assimilation and prognostic whole ice sheet modelling with the variationally derived, higher order, open source, and fully parallel ice sheet model VarGlaS

    Directory of Open Access Journals (Sweden)

    D. J. Brinkerhoff

    2013-07-01

    Full Text Available We introduce a novel, higher order, finite element ice sheet model called VarGlaS (Variational Glacier Simulator, which is built on the finite element framework FEniCS. Contrary to standard procedure in ice sheet modelling, VarGlaS formulates ice sheet motion as the minimization of an energy functional, conferring advantages such as a consistent platform for making numerical approximations, a coherent relationship between motion and heat generation, and implicit boundary treatment. VarGlaS also solves the equations of enthalpy rather than temperature, avoiding the solution of a contact problem. Rather than include a lengthy model spin-up procedure, VarGlaS possesses an automated framework for model inversion. These capabilities are brought to bear on several benchmark problems in ice sheet modelling, as well as a 500 yr simulation of the Greenland ice sheet at high resolution. VarGlaS performs well in benchmarking experiments and, given a constant climate and a 100 yr relaxation period, predicts a mass evolution of the Greenland ice sheet that matches present-day observations of mass loss. VarGlaS predicts a thinning in the interior and thickening of the margins of the ice sheet.

  6. Spleen-dependent regulation of antigenic variation in malaria parasites: Plasmodium knowlesi SICAvar expression profiles in splenic and asplenic hosts.

    Directory of Open Access Journals (Sweden)

    Stacey A Lapp

    Full Text Available BACKGROUND: Antigenic variation by malaria parasites was first described in Plasmodium knowlesi, which infects humans and macaque monkeys, and subsequently in P. falciparum, the most virulent human parasite. The schizont-infected cell agglutination (SICA variant proteins encoded by the SICAvar multigene family in P. knowlesi, and Erythrocyte Membrane Protein-1 (EMP-1 antigens encoded by the var multigene family in P. falciparum, are expressed at the surface of infected erythrocytes, are associated with virulence, and serve as determinants of naturally acquired immunity. A parental P. knowlesi clone, Pk1(A+, and a related progeny clone, Pk1(B+1+, derived by an in vivo induced variant antigen switch, were defined by the expression of distinct SICA variant protein doublets of 210/190 and 205/200 kDa, respectively. Passage of SICA[+] infected erythrocytes through splenectomized rhesus monkeys results in the SICA[-] phenotype, defined by the lack of surface expression and agglutination with variant specific antisera. PRINCIPAL FINDINGS: We have investigated SICAvar RNA and protein expression in Pk1(A+, Pk1(B+1+, and SICA[-] parasites. The Pk1(A+ and Pk1(B+1+ parasites express different distinct SICAvar transcript and protein repertoires. By comparison, SICA[-] parasites are characterized by a vast reduction in SICAvar RNA expression, the lack of full-length SICAvar transcript signals on northern blots, and correspondingly, the absence of any SICA protein detected by mass spectrometry. SIGNIFICANCE: SICA protein expression may be under transcriptional as well as post-transcriptional control, and we show for the first time that the spleen, an organ central to blood-stage immunity in malaria, exerts an influence on these processes. Furthermore, proteomics has enabled the first in-depth characterization of SICA[+] protein phenotypes and we show that the in vivo switch from Pk1(A+ to Pk1(B+1+ parasites resulted in a complete change in SICA profiles. These

  7. Spleen-Dependent Regulation of Antigenic Variation in Malaria Parasites: Plasmodium knowlesi SICAvar Expression Profiles in Splenic and Asplenic Hosts

    Science.gov (United States)

    Lapp, Stacey A.; Korir-Morrison, Cindy; Jiang, Jianlin; Bai, Yaohui; Corredor, Vladimir; Galinski, Mary R.

    2013-01-01

    Background Antigenic variation by malaria parasites was first described in Plasmodium knowlesi, which infects humans and macaque monkeys, and subsequently in P. falciparum, the most virulent human parasite. The schizont-infected cell agglutination (SICA) variant proteins encoded by the SICAvar multigene family in P. knowlesi, and Erythrocyte Membrane Protein-1 (EMP-1) antigens encoded by the var multigene family in P. falciparum, are expressed at the surface of infected erythrocytes, are associated with virulence, and serve as determinants of naturally acquired immunity. A parental P. knowlesi clone, Pk1(A+), and a related progeny clone, Pk1(B+)1+, derived by an in vivo induced variant antigen switch, were defined by the expression of distinct SICA variant protein doublets of 210/190 and 205/200 kDa, respectively. Passage of SICA[+] infected erythrocytes through splenectomized rhesus monkeys results in the SICA[-] phenotype, defined by the lack of surface expression and agglutination with variant specific antisera. Principal Findings We have investigated SICAvar RNA and protein expression in Pk1(A+), Pk1(B+)1+, and SICA[-] parasites. The Pk1(A+) and Pk1(B+)1+ parasites express different distinct SICAvar transcript and protein repertoires. By comparison, SICA[-] parasites are characterized by a vast reduction in SICAvar RNA expression, the lack of full-length SICAvar transcript signals on northern blots, and correspondingly, the absence of any SICA protein detected by mass spectrometry. Significance SICA protein expression may be under transcriptional as well as post-transcriptional control, and we show for the first time that the spleen, an organ central to blood-stage immunity in malaria, exerts an influence on these processes. Furthermore, proteomics has enabled the first in-depth characterization of SICA[+] protein phenotypes and we show that the in vivo switch from Pk1(A+) to Pk1(B+)1+ parasites resulted in a complete change in SICA profiles. These results

  8. Mapping replication dynamics in Trypanosoma brucei reveals a link with telomere transcription and antigenic variation.

    Science.gov (United States)

    Devlin, Rebecca; Marques, Catarina A; Paape, Daniel; Prorocic, Marko; Zurita-Leal, Andrea C; Campbell, Samantha J; Lapsley, Craig; Dickens, Nicholas; McCulloch, Richard

    2016-05-26

    Survival of Trypanosoma brucei depends upon switches in its protective Variant Surface Glycoprotein (VSG) coat by antigenic variation. VSG switching occurs by frequent homologous recombination, which is thought to require locus-specific initiation. Here, we show that a RecQ helicase, RECQ2, acts to repair DNA breaks, including in the telomeric site of VSG expression. Despite this, RECQ2 loss does not impair antigenic variation, but causes increased VSG switching by recombination, arguing against models for VSG switch initiation through direct generation of a DNA double strand break (DSB). Indeed, we show DSBs inefficiently direct recombination in the VSG expression site. By mapping genome replication dynamics, we reveal that the transcribed VSG expression site is the only telomeric site that is early replicating - a differential timing only seen in mammal-infective parasites. Specific association between VSG transcription and replication timing reveals a model for antigenic variation based on replication-derived DNA fragility.

  9. Variation in the volatile constituents of Artemisia annua var. CIM-Arogya during plant ontogeny.

    Science.gov (United States)

    Padalia, Rajendra C; Verma, Ram S; Chauhan, Amit; Chanotiya, Chandan S; Yadav, Anju

    2011-02-01

    The essential oils yield and composition of the aerial parts of A. annua var. CIM-Arogya grown in Uttarakhand, India were analyzed and compared by capillary GC and GC-MS at different stages of development. The analysis led to the identification of 81 constituents forming 91.0%-97.1% of the essential oils compositions. The essential oil content of the aerial parts was found to vary from 0.3% to 0.7% at different stages of growth. A. annua crop harvested at full flowering and seed setting stage gave higher yield of essential oil (0.6%, 0.7%) than that harvested at pre flowering (0.5%), late vegetative (0.4%, 0.5%), mid vegetative (0.4%, 0.4%) and early vegetative stages (0.3%, 0.3%). The essential oils at different stages of growth showed monoterpenoids (38.5%-72.0%) and sesquiterpenoids (22.2%-48.2%) as major grouped constituents. The major constituents identified were camphor (22.8%-42.6%), 1,8-cineole (3.7%-8.4%), linalool (<0.1%-11.9%), beta-caryophyllene (2.0%-9.2%), (E)-beta-farnesene (1.3%-8.5%), germacrene D (0.5%-7.3%) and 1-epi-cubenol (0.7%-5.2%) in essential oil samples collected at different crop stages.

  10. dbVar

    Data.gov (United States)

    U.S. Department of Health & Human Services — dbVar is a database of genomic structural variation. It accepts data from all species and includes clinical data. It can accept diverse types of events, including...

  11. Effects of intraspecific variation in white cabbage (Brassica oleracea var. capitata) on soil organisms

    NARCIS (Netherlands)

    Kabouw, P.; Van der Putten, W.H.; Van Dam, N.M.; Biere, A.

    2010-01-01

    Intraspecific variation in plants can affect soil organisms. However, little is known about whether the magnitude of the effect depends on the degree of interaction with the roots. We analyzed effects of plant intraspecific variation on root herbivores and other soil organisms that interact directly

  12. Effects of intraspecific variation in white cabbage (Brassica oleracea var. Capitata) on soil ogranisms

    NARCIS (Netherlands)

    Kabouw, P.; Putten, van der W.H.; Dam, van N.M.; Biere, A.

    2010-01-01

    Intraspecific variation in plants can affect soil organisms. However, little is known about whether the magnitude of the effect depends on the degree of interaction with the roots. We analyzed effects of plant intraspecific variation on root herbivores and other soil organisms that interact directly

  13. Influenza A virus hemagglutinin antibody escape promotes neuraminidase antigenic variation and drug resistance.

    Directory of Open Access Journals (Sweden)

    Scott E Hensley

    Full Text Available Drugs inhibiting the influenza A virus (IAV neuraminidase (NA are the cornerstone of anti-IAV chemotherapy and prophylaxis in man. Drug-resistant mutations in NA arise frequently in human isolates, limiting the therapeutic application of NA inhibitors. Here, we show that antibody-driven antigenic variation in one domain of the H1 hemagglutinin Sa site leads to compensatory mutations in NA, resulting in NA antigenic variation and acquisition of drug resistance. These findings indicate that influenza A virus resistance to NA inhibitors can potentially arise from antibody driven HA escape, confounding analysis of influenza NA evolution in nature.

  14. Monitoring antigenic variations of enterovirus 71: implications for virus surveillance and vaccine development.

    Directory of Open Access Journals (Sweden)

    Min-Yuan Chia

    2014-07-01

    Full Text Available Enterovirus 71 (EV71 causes life-threatening epidemics in Asia and can be phylogenetically classified into three major genogroups (A ∼ C including 11 genotypes (A, B1 ∼ B5, and C1 ∼ C5. Recently, EV71 epidemics occurred cyclically in Taiwan with different genotypes. In recent years, human studies using post-infection sera obtained from children have detected antigenic variations among different EV71 strains. Therefore, surveillance of enterovirus 71 should include phylogenetic and antigenic analysis. Due to limitation of sera available from children with EV71 primary infection, suitable animal models should be developed to generate a panel of antisera for monitoring EV71 antigenic variations. Twelve reference strains representing the 11 EV71 genotypes were grown in rhabdomyosarcoma cells. Infectious EV71 particles were purified and collected to immunize rabbits. The rabbit antisera were then employed to measure neutralizing antibody titers against the 12 reference strains and 5 recent strains. Rabbits immunized with genogroup B and C viruses consistently have a lower neutralizing antibody titers against genogroup A (≧ 8-fold difference and antigenic variations between genogroup B and C viruses can be detected but did not have a clear pattern, which are consistent with previous human studies. Comparison between human and rabbit neutralizing antibody profiles, the results showed that ≧ 8-fold difference in rabbit cross-reactive antibody ratios could be used to screen EV71 isolates for identifying potential antigenic variants. In conclusion, a rabbit model was developed to monitor antigenic variations of EV71, which are critical to select vaccine strains and predict epidemics.

  15. A role for RAD51 and homologous recombination in Trypanosoma brucei antigenic variation.

    Science.gov (United States)

    McCulloch, R; Barry, J D

    1999-11-01

    Antigenic variation is an immune evasion strategy used by African trypanosomes, in which the parasites periodically switch the expression of VSG genes that encode their protective variant surface glycoprotein coat. Two main routes exist for VSG switching: changing the transcriptional status between an active and an inactive copy of the site of VSG expression, called the bloodstream VSG expression site, or recombination reactions that move silent VSGs or VSG copies into the actively transcribed expression site. Nothing is known about the proteins that control and catalyze these switching reactions. This study describes the cloning of a trypanosome gene encoding RAD51, an enzyme involved in DNA break repair and genetic exchange, and analysis of the role of the enzyme in antigenic variation. Trypanosomes genetically inactivated in the RAD51 gene were shown to be viable, and had phenotypes consistent with lacking functional expression of an enzyme of homologous recombination. The mutants had an impaired ability to undergo VSG switching, and it appeared that both recombinational and transcriptional switching reactions were down-regulated, indicating that RAD51 either catalyzes or regulates antigenic variation. Switching events were still detectable, however, so it appears that trypanosome factors other than RAD51 can also provide for antigenic variation.

  16. Fine-scale genetic characterization of Plasmodium falciparum chromosome 7 encompassing the antigenic var and the drug-resistant pfcrt genes

    Indian Academy of Sciences (India)

    Ruchi Bajaj; Sujata Mohanty; A. P. Dash; Aparup Das

    2008-04-01

    The fact that malaria is still an uncontrolled disease is reflected by the genetic organization of the parasite genome. Efforts to curb malaria should begin with proper understanding of the mechanism by which the parasites evade human immune system and evolve resistance to different antimalarial drugs. We have initiated such a study and presented herewith the results from the in silico understanding of a seventh chromosomal region of the malarial parasite Plasmodium falciparum encompassing the antigenic var genes (coding pfemp1) and the drug-resistant gene pfcrt located at a specified region of the chromosome 7. We found 60 genes of various functions and lengths, majority (61.67%) of them were performing known functions. Almost all the genes have orthologs in other four species of Plasmodium, of which P. chabaudi seems to be the closest to P. falciparum. However, only two genes were found to be paralogous. Interestingly, the drug-resistant gene, pfcrt was found to be surrounded by seven genes coding for several CG proteins out of which six were reported to be responsible for providing drug resistance to P. vivax. The intergenic regions, in this specified region were generally large in size, majority (73%) of them were of more than 500 nucleotide bp length. We also designed primers for amplification of 21 noncoding DNA fragments in the whole region for estimating genetic diversity and inferring the evolutionary history of this region of P. falciparum genome.

  17. Surface co-expression of two different PfEMP1 antigens on single Plasmodium falciparum-infected erythrocytes facilitates binding to ICAM1 and PECAM1

    DEFF Research Database (Denmark)

    Joergensen, Louise; Bengtsson, Dominique C; Bengtsson, Anja;

    2010-01-01

    The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens play a major role in cytoadhesion of infected erythrocytes (IE), antigenic variation, and immunity to malaria. The current consensus on control of variant surface antigen expression is that only one PfEMP1 encoded by one var...

  18. Antigenic variation by Borrelia hermsii occurs through recombination between extragenic repetitive elements on linear plasmids.

    Science.gov (United States)

    Dai, Qiyuan; Restrepo, Blanca I; Porcella, Stephen F; Raffel, Sandra J; Schwan, Tom G; Barbour, Alan G

    2006-06-01

    The relapsing fever agent Borrelia hermsii undergoes multiphasic antigenic variation through gene conversion of a unique expression site on a linear plasmid by an archived variable antigen gene. To further characterize this mechanism we assessed the repertoire and organization of archived variable antigen genes by sequencing approximately 85% of plasmids bearing these genes. Most archived genes shared with the expressed gene a UHS), that surrounded the start codon. The 59 archived variable antigen genes were arrayed in clusters with 13 repetitive, 214 nt long downstream homology sequence (DHS) elements distributed among them. A fourteenth DHS element was downstream of the expression locus. Informative nucleotide polymorphisms in UHS regions and DHS elements were applied to the analysis of the expression site of relapse serotypes from 60 infected mice in a prospective study. For most recombinations, the upstream crossover occurred in the UHS's second half, and the downstream crossover was in the DHS's second half. Usually the closest archival DHS element was used, but occasionally a more distant DHS was employed. The downstream extragenic crossover site in B. hermsii contrasts with the upstream [corrected] extragenic crossover site for antigenic variation in African trypanosomes.

  19. “Nothing is permanent but change”* -- Antigenic variation in persistent bacterial pathogens

    Science.gov (United States)

    Palmer, Guy H.; Bankhead, Troy; Lukehart, Sheila A.

    2012-01-01

    Summary Pathogens persist in immunocompetent mammalian hosts using various strategies, including evasion of immune effectors by antigenic variation. Among highly antigenically variant bacteria, gene conversion is used to generate novel expressed variants from otherwise silent donor sequences. Recombination using oligonucleotide segments from multiple donors is a combinatorial mechanism that tremendously expands the variant repertoire, allowing thousands of variants to be generated from a relatively small donor pool. Three bacterial pathogens, each encoded by a small genome (Borrelia burgdorferi VlsE diversity is encoded and expressed on a linear plasmid required for persistence and recent experiments have demonstrated that VlsE recombination is necessary for persistence in the immunocompetent host. In contrast, both Treponema pallidum TprK and Anaplasma marginale Msp2 expression sites and donors are chromosomally encoded. Both T. pallidum and A. marginale generate antigenic variants in vivo in individual hosts and studies at the population level reveal marked strain diversity in the variant repertoire that may underlie pathogen strain structure and the capacity for re-infection and heterologous strain superinfection. Here, we review gene conversion in bacterial antigenic variation and discuss the short- and long-term selective pressures that shape the variant repertoire. PMID:19709057

  20. 'Nothing is permanent but change'- antigenic variation in persistent bacterial pathogens.

    Science.gov (United States)

    Palmer, Guy H; Bankhead, Troy; Lukehart, Sheila A

    2009-12-01

    Pathogens persist in immunocompetent mammalian hosts using various strategies, including evasion of immune effectors by antigenic variation. Among highly antigenically variant bacteria, gene conversion is used to generate novel expressed variants from otherwise silent donor sequences. Recombination using oligonucleotide segments from multiple donors is a combinatorial mechanism that tremendously expands the variant repertoire, allowing thousands of variants to be generated from a relatively small donor pool. Three bacterial pathogens, each encoded by a small genome (Borrelia burgdorferi VlsE diversity is encoded and expressed on a linear plasmid required for persistence and recent experiments have demonstrated that VlsE recombination is necessary for persistence in the immunocompetent host. In contrast, both Treponema pallidum TprK and Anaplasma marginale Msp2 expression sites and donors are chromosomally encoded. Both T. pallidum and A. marginale generate antigenic variants in vivo in individual hosts and studies at the population level reveal marked strain diversity in the variant repertoire that may underlie pathogen strain structure and the capacity for re-infection and heterologous strain superinfection. Here, we review gene conversion in bacterial antigenic variation and discuss the short- and long-term selective pressures that shape the variant repertoire.

  1. Molluscicidal activity of crown of Christ (Euphorbia splendens var. hislopii (Euphorbiaceae latex submitted to pH variation

    Directory of Open Access Journals (Sweden)

    Vasconcellos Maurício Carvalho

    2003-01-01

    Full Text Available Laboratory and field bioassays have confirmed the specificity of the molluscicidal activity of the Euphorbia splendens var. hislopii latex (crown of Christ (Euphorbiaceae over snails of the species Biomphalaria glabrata, B. tenagophila, B. straminea, B. pfeifferi and Bulinus sp. in the control of Schistosoma mansoni. In the present study, the effect of the pH variation on lethal concentration (LC90 over B. tenagophila was evaluated. Bioassays with the aqueous solutions of the latex ranging from 0.4 to 12 µl/l were adjusted for pH of 5.0; 6.0; 7.0 and 8.0, and tested in accordance with methods standardized by World Health Organization. The results obtained indicated that the minor concentration of the latex occurred at pH 6.0 (LC90 = 3.2 µl/l and the maximum at pH 8.0 (LC90 = 10.3 µl/l. Lethal concentrations adjusted for pH 5.0 and 7.0 were 3.4 µl/l and 4,7µl/l, respectively. From the results it could be concluded that the molluscicidal toxicity was not altered when the concentrations were adjusted for pH 5.0 and 6.0, as we observed that mortality rate was 100% starting at a concentration of 2.0 µl/l, not the same for the concentrations with adjustment for pH 7.0 and 8.0.

  2. A role for RAD51 and homologous recombination in Trypanosoma brucei antigenic variation

    OpenAIRE

    1999-01-01

    Antigenic variation is an immune evasion strategy used by African trypanosomes, in which the parasites periodically switch the expression of VSG genes that encode their protective variant surface glycoprotein coat. Two main routes exist for VSG switching: changing the transcriptional status between an active and an inactive copy of the site of VSG expression, called the bloodstream VSG expression site, or recombination reactions that move silent VSGs or VSG copies into the actively transcribe...

  3. Mismatch repair regulates homologous recombination, but has little influence on antigenic variation, in Trypanosoma brucei.

    Science.gov (United States)

    Bell, Joanna S; McCulloch, Richard

    2003-11-14

    Antigenic variation is critical in the life of the African trypanosome, as it allows the parasite to survive in the face of host immunity and enhance its transmission to other hosts. Much of trypanosome antigenic variation uses homologous recombination of variant surface glycoprotein (VSG)-encoding genes into specialized transcription sites, but little is known about the processes that regulate it. Here we describe the effects on VSG switching when two central mismatch repair genes, MSH2 and MLH1, are mutated. We show that disruption of the parasite mismatch repair system causes an increased frequency of homologous recombination, both between perfectly matched DNA molecules and between DNA molecules with divergent sequences. Mismatch repair therefore provides an important regulatory role in homologous recombination in this ancient eukaryote. Despite this, the mismatch repair system has no detectable role in regulating antigenic variation, meaning that VSG switching is either immune to mismatch selection or that mismatch repair acts in a subtle manner, undetectable by current assays.

  4. Argania spinosa var. mutica and var. apiculata: variation of fatty-acid composition, phenolic content, and antioxidant and α-amylase-inhibitory activities among varieties, organs, and development stages.

    Science.gov (United States)

    El Adib, Saifeddine; Aissi, Oumayma; Charrouf, Zoubida; Ben Jeddi, Fayçal; Messaoud, Chokri

    2015-09-01

    Argania spinosa includes two varieties, var. apiculata and var. mutica. These argan varieties were introduced into Tunisia in ancient times and are actually cultivated in some botanic gardens. Little is known about the chemical differentiation among these argan varieties. Hence, the aim of this study was to determine the fatty-acid composition, the total phenolic and flavonoid contents, and the antioxidant and α-amylase-inhibitory activities of leaf, seed, and pulp extracts of both argan varieties harvested during the months of January to April. The fatty-acid distribution was found to depend on the argan variety, the plant organ, and the harvest time. Significant variations in the phenolic contents were observed between the investigated varieties as well as between leaves, pulps, and seeds of each variety. As expected, phenolic compounds were found to be contributors to the antioxidant and α-amylase-inhibitory activities of both argan varieties. The chemical differentiation observed among the two argan varieties, based mainly on the fatty-acid composition, might have some chemotaxonomic value. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  5. DNA break site at fragile subtelomeres determines probability and mechanism of antigenic variation in African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Lucy Glover

    2013-03-01

    Full Text Available Antigenic variation in African trypanosomes requires monoallelic transcription and switching of variant surface glycoprotein (VSG genes. The transcribed VSG, always flanked by '70 bp'-repeats and telomeric-repeats, is either replaced through DNA double-strand break (DSB repair or transcriptionally inactivated. However, little is known about the subtelomeric DSBs that naturally trigger antigenic variation in Trypanosoma brucei, the subsequent DNA damage responses, or how these responses determine the mechanism of VSG switching. We found that DSBs naturally accumulate close to both transcribed and non-transcribed telomeres. We then induced high-efficiency meganuclease-mediated DSBs and monitored DSB-responses and DSB-survivors. By inducing breaks at distinct sites within both transcribed and silent VSG transcription units and assessing local DNA resection, histone modification, G2/M-checkpoint activation, and both RAD51-dependent and independent repair, we reveal how breaks at different sites trigger distinct responses and, in 'active-site' survivors, different switching mechanisms. At the active site, we find that promoter-adjacent breaks typically failed to trigger switching, 70 bp-repeat-adjacent breaks almost always triggered switching through 70 bp-repeat recombination (∼60% RAD51-dependent, and telomere-repeat-adjacent breaks triggered switching through loss of the VSG expression site (25% of survivors. Expression site loss was associated with G2/M-checkpoint bypass, while 70 bp-repeat-recombination was associated with DNA-resection, γH2A-focus assembly and a G2/M-checkpoint. Thus, the probability and mechanism of antigenic switching are highly dependent upon the location of the break. We conclude that 70 bp-repeat-adjacent and telomere-repeat-adjacent breaks trigger distinct checkpoint responses and VSG switching pathways. Our results show how subtelomere fragility can generate the triggers for the major antigenic variation mechanisms in

  6. DNA break site at fragile subtelomeres determines probability and mechanism of antigenic variation in African trypanosomes.

    Science.gov (United States)

    Glover, Lucy; Alsford, Sam; Horn, David

    2013-03-01

    Antigenic variation in African trypanosomes requires monoallelic transcription and switching of variant surface glycoprotein (VSG) genes. The transcribed VSG, always flanked by '70 bp'-repeats and telomeric-repeats, is either replaced through DNA double-strand break (DSB) repair or transcriptionally inactivated. However, little is known about the subtelomeric DSBs that naturally trigger antigenic variation in Trypanosoma brucei, the subsequent DNA damage responses, or how these responses determine the mechanism of VSG switching. We found that DSBs naturally accumulate close to both transcribed and non-transcribed telomeres. We then induced high-efficiency meganuclease-mediated DSBs and monitored DSB-responses and DSB-survivors. By inducing breaks at distinct sites within both transcribed and silent VSG transcription units and assessing local DNA resection, histone modification, G2/M-checkpoint activation, and both RAD51-dependent and independent repair, we reveal how breaks at different sites trigger distinct responses and, in 'active-site' survivors, different switching mechanisms. At the active site, we find that promoter-adjacent breaks typically failed to trigger switching, 70 bp-repeat-adjacent breaks almost always triggered switching through 70 bp-repeat recombination (∼60% RAD51-dependent), and telomere-repeat-adjacent breaks triggered switching through loss of the VSG expression site (25% of survivors). Expression site loss was associated with G2/M-checkpoint bypass, while 70 bp-repeat-recombination was associated with DNA-resection, γH2A-focus assembly and a G2/M-checkpoint. Thus, the probability and mechanism of antigenic switching are highly dependent upon the location of the break. We conclude that 70 bp-repeat-adjacent and telomere-repeat-adjacent breaks trigger distinct checkpoint responses and VSG switching pathways. Our results show how subtelomere fragility can generate the triggers for the major antigenic variation mechanisms in the African

  7. Improvements in the HbVar database of human hemoglobin variants and thalassemia mutations for population and sequence variation studies.

    NARCIS (Netherlands)

    G.P. Patrinos (George); B. Giardine (Belinda); C. Riemer (Cathy); W. Miller (Webb); D.H. Chui (David); N.P. Anagnou (Nicholas); H. Wajcman (Henri); R.C. Hardison (Ross)

    2004-01-01

    textabstractHbVar (http://globin.cse.psu.edu/globin/hbvar/) is a relational database developed by a multi-center academic effort to provide up-to-date and high quality information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and

  8. Improvements in the HbVar database of human hemoglobin variants and thalassemia mutations for population and sequence variation studies.

    NARCIS (Netherlands)

    G.P. Patrinos (George); B. Giardine (Belinda); C. Riemer (Cathy); W. Miller (Webb); D.H. Chui (David); N.P. Anagnou (Nicholas); H. Wajcman (Henri); R.C. Hardison (Ross)

    2004-01-01

    textabstractHbVar (http://globin.cse.psu.edu/globin/hbvar/) is a relational database developed by a multi-center academic effort to provide up-to-date and high quality information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and hemogl

  9. New cytotypes of Pteris ensiformis var. victoriae from Indonesia

    Directory of Open Access Journals (Sweden)

    Muhammad Efendi

    2014-12-01

    Full Text Available New cytotypes of Pteris ensiformis var. victoriae and one cytotype of var. ensiformis are recorded from Indonesia: var. victoriae with 2n=58 (sexual diploid from Gorontalo, North       Sulawesi, and 2n=87 (triploid from Lombok Island and Bogor, West Java; and var. ensiformis with 2n=116 (sexual tetraploid. The diploid is smaller than the triploid in plant size. Results indicate a cytological variation in var. victoriae, like in var. ensiformis.

  10. A VAR2CSA

    DEFF Research Database (Denmark)

    Sungwa, Matondo; Thrane, Susan; Janitzek, Christoph Mikkel

    2017-01-01

    to make a, post expression, dual antigen conjugate vaccine, comprising two clinically tested antigen candidates (CSP and VAR2CSA).  Methods: The DBL1x-DBL2x-ID2a region of VAR2CSA was genetically fused with SpyTag at N-terminus. The full-length CSP antigen was genetically fused to C-terminal Spy......Catcher peptide. The covalent interaction between SpyTag/SpyCatcher enables the formation of DBL1x-DBL2x-ID2a:CSP conjugate vaccine. Immunogenicity and quality of antibody responses induced by the conjugate vaccine, as well as a control CSP-SpyCatcher vaccine, was tested in BALB/c mice.  Results: Serum samples...... obtained from mice immunized with the conjugate vaccine were able to recognize both untagged DBL1x-DBL2x-ID2a as well as CSP antigen. Moreover, the geometric mean anti-CSP antibody titer was 1.9-fold higher in serum (at day 35 and 55 post-first immunization) from mice immunized with the conjugate vaccine...

  11. vsp Gene Expression by Giardia lamblia Clone GS/M-83-H7 during Antigenic Variation In Vivo and In Vitro

    OpenAIRE

    2001-01-01

    Giardia lamblia infections are associated with antigenic variation of the parasite, which is generated by a continuous change of the variant-specific surface proteins (VSPs). Many investigations on the process of antigenic variation were based on the use of G. lamblia clone GS/M-83-H7, which expresses VSP H7 as its major surface antigen. In the present study, mice were infected with the aforementioned clonal line to investigate vsp gene expression during the complex process of antigenic varia...

  12. Human antibody responses to VlsE antigenic variation protein of Borrelia burgdorferi.

    Science.gov (United States)

    Lawrenz, M B; Hardham, J M; Owens, R T; Nowakowski, J; Steere, A C; Wormser, G P; Norris, S J

    1999-12-01

    VlsE is a 35-kDa surface-exposed lipoprotein of Borrelia burgdorferi that was shown previously to undergo antigenic variation through segmental recombination of silent vls cassettes with vlsE during experimental mouse infections. Previous data had indicated that sera from North American Lyme disease patients and experimentally infected animals contained antibodies reactive with VlsE. In this study, sera from patients with Lyme disease, syphilis, and autoimmune conditions as well as from healthy controls were examined for reactivity with VlsE by Western blotting and enzyme-linked immunosorbent assay (ELISA). Strong Western blot reactivity to a recombinant VlsE cassette region protein was obtained consistently with Lyme disease sera. Although sera from Lyme disease patients also reacted with a band corresponding to VlsE in B. burgdorferi B31-5A3, interpretation was complicated by low levels of VlsE expression in in vitro-cultured B. burgdorferi and by the presence of comigrating bands. An ELISA using recombinant VlsE was compared with an ELISA using sonically disrupted B. burgdorferi as the antigen. For a total of 93 Lyme disease patient sera examined, the VlsE ELISA yielded sensitivities of 63% for culture-confirmed erythema migrans cases and 92% for later stages, as compared to 61 and 98%, respectively, for the "whole-cell" ELISA. The specificities of the two assays with healthy blood donor sera were comparable, but the VlsE ELISA was 90% specific with sera from syphilis patients, compared to 20% specificity for the whole-cell ELISA with this group. Neither assay showed reactivity with a panel of sera from 20 non-Lyme disease arthritis patients or 20 systemic lupus erythematosus patients. Our results indicate that VlsE may be useful in the immunodiagnosis of Lyme disease and may offer greater specificity than ELISAs using whole B. burgdorferi as the antigen.

  13. Provenance and family variation of Pinus caribaea var. hondurensis from Guatemala and Honduras, grown in Brazil, Colombia and Venezuela

    Directory of Open Access Journals (Sweden)

    Moura Vicente Pongitory Gifoni

    2001-01-01

    Full Text Available Pinus caribaea var. hondurensis (Sénécl Barr. & Golf. is a tropical pine that naturally occurs in lowland areas of Belize, El Salvador, Guatemala, Honduras, Nicaragua, and eastern Mexico. It has been one of the most studied tropical pines and the one with the most commercial importance in Brazil. The objective of this work was to select the best provenances for plantations and best trees in families for the establishment of seed orchards. For that a trial with five provenances and 47 open-pollinated families was planted near Planaltina, Federal District, in the Cerrado Region of Brazil. The provenances tested were Poptun (Guatemala, Gualjoco, Los Limones, El Porvenir and Santa Cruz de Yojoa (Honduras and assessed at 12 years of age. Poptun and Gualjoco had larger volume, and Los Limones and El Porvenir the lowest incidence of forks and foxtails. Individual tree heritabilities for volume, stem form and branch diameter were 0.34, 0.06, and 0.26 respectively. More than 90% of the trees had defects, common in unimproved P. caribaea. Selection criteria for quality traits need to be relaxed in the first generation of breeding to allow for larger genetic gains in productivity. Results from this test compared with P. caribaea var. hondurensis trials in other Brazilian, Colombian and Venezuelan sites suggest that provenance x site and family x site interactions are not as strong as in other pine species.

  14. Telomere length affects the frequency and mechanism of antigenic variation in Trypanosoma brucei.

    Directory of Open Access Journals (Sweden)

    Galadriel A Hovel-Miner

    Full Text Available Trypanosoma brucei is a master of antigenic variation and immune response evasion. Utilizing a genomic repertoire of more than 1000 Variant Surface Glycoprotein-encoding genes (VSGs, T. brucei can change its protein coat by "switching" from the expression of one VSG to another. Each active VSG is monoallelically expressed from only one of approximately 15 subtelomeric sites. Switching VSG expression occurs by three predominant mechanisms, arguably the most significant of which is the non-reciprocal exchange of VSG containing DNA by duplicative gene conversion (GC. How T. brucei orchestrates its complex switching mechanisms remains to be elucidated. Recent work has demonstrated that an exogenous DNA break in the active site could initiate a GC based switch, yet the source of the switch-initiating DNA lesion under natural conditions is still unknown. Here we investigated the hypothesis that telomere length directly affects VSG switching. We demonstrate that telomerase deficient strains with short telomeres switch more frequently than genetically identical strains with long telomeres and that, when the telomere is short, switching preferentially occurs by GC. Our data supports the hypothesis that a short telomere at the active VSG expression site results in an increase in subtelomeric DNA breaks, which can initiate GC based switching. In addition to their significance for T. brucei and telomere biology, the findings presented here have implications for the many diverse pathogens that organize their antigenic genes in subtelomeric regions.

  15. Virulence-related physiological changes and antigenic variation in populations of Streptococcus mutans colonizing gnotobiotic rats.

    Science.gov (United States)

    Gibbons, R J; Qureshi, J V

    1980-09-01

    The purpose of this study was to determine if populations of Streptococcus mutans which were undergoing antigenic variation while colonizing gnotobiotic rats concomitantly became altered in physiological characteristics which affected their virulence. S. mutans strain JBP (serotype c), which was freshly isolated from a carious lesion in a 6-year old child, was used to inoculate gnotobiotic rats; uninfected animals served as controls. Substrains were isolated from animals 1, 2, 3, 4, and 12 weeks after infection; samples of pilocarpine-stimulated saliva were also obtained from representative animals for antibody analyses. Isolates derived from stock cultures of strain JBP proved to be homogeneous with respect to all of the physiological characteristics monitored. However, substrains isolated from the animals within 4 weeks after infection were altered with respect to their ability to agglutinate in the presence of sucrose, their ability to form adherent growth in sucrose broth, and the terminal pH attained in glucose broth. Some isolates obtained 12 weeks after infection no longer synthesized detectable levels of c antigen or intracellular glycogen, and they formed atypical smooth colonies on mitis salivarius agar. With an enzyme-linked immunosorbent assay, low levels of immunoglobulin A (IgA) antibodies reactive with whole JBP cells were detected in saliva samples of uninfected control animals at each sampling period; these evidently were induced to antigens contained in the diet of the animals. Significantly higher levels of IgA antibodies were present in saliva samples from animals infected with strain JBP for 3 weeks or longer. Thus, the emergence of antigenic and physiological variants of S. mutans in the animals was paralleled by increased levels of salivary IgA antibodies. The reactivity of salivary IgG with JBP cells was low, and it fluctuated in both groups of animals. No antibodies of the IgM class were detected. When tested in gnotobiotic rats, several

  16. Genetic variation of lodgepole pine, Pinus contorta var. latifolia, chemical and physical defenses that affect mountain pine beetle, Dendroctonus ponderosae, attack and tree mortality.

    Science.gov (United States)

    Ott, Daniel S; Yanchuk, Alvin D; Huber, Dezene P W; Wallin, Kimberly F

    2011-09-01

    Plant secondary chemistry is determined by both genetic and environmental factors, and while large intraspecific variation in secondary chemistry has been reported frequently, the levels of genetic variation of many secondary metabolites in forest trees in the context of potential resistance against pests have been rarely investigated. We examined the effect of tree genotype and environment/site on the variation in defensive secondary chemistry of lodgepole pine, Pinus contorta var. latifolia, against the fungus, Grosmannia clavigera (formerly known as Ophiostoma clavigerum), associated with the mountain pine beetle, Dendroctonus ponderosae. Terpenoids were analyzed in phloem samples from 887, 20-yr-old trees originating from 45 half-sibling families planted at two sites. Samples were collected both pre- and post-inoculation with G. clavigera. Significant variation in constitutive and induced terpenoid compounds was attributed to differences among families. The response to the challenge inoculation with G. clavigera was strong for some individual compounds, but primarily for monoterpenoids. Environment (site) also had a significant effect on the accumulation of some compounds, whereas for others, no significant environmental effect occurred. However, for a few compounds significant family x environment interactions were found. These results suggest that P. c. latifolia secondary chemistry is under strong genetic control, but the effects depend on the individual compounds and whether or not they are expressed constitutively or following induction.

  17. The use of high-throughput DNA sequencing in the investigation of antigenic variation: application to Neisseria species.

    Directory of Open Access Journals (Sweden)

    John K Davies

    Full Text Available Antigenic variation occurs in a broad range of species. This process resembles gene conversion in that variant DNA is unidirectionally transferred from partial gene copies (or silent loci into an expression locus. Previous studies of antigenic variation have involved the amplification and sequencing of individual genes from hundreds of colonies. Using the pilE gene from Neisseria gonorrhoeae we have demonstrated that it is possible to use PCR amplification, followed by high-throughput DNA sequencing and a novel assembly process, to detect individual antigenic variation events. The ability to detect these events was much greater than has previously been possible. In N. gonorrhoeae most silent loci contain multiple partial gene copies. Here we show that there is a bias towards using the copy at the 3' end of the silent loci (copy 1 as the donor sequence. The pilE gene of N. gonorrhoeae and some strains of Neisseria meningitidis encode class I pilin, but strains of N. meningitidis from clonal complexes 8 and 11 encode a class II pilin. We have confirmed that the class II pili of meningococcal strain FAM18 (clonal complex 11 are non-variable, and this is also true for the class II pili of strain NMB from clonal complex 8. In addition when a gene encoding class I pilin was moved into the meningococcal strain NMB background there was no evidence of antigenic variation. Finally we investigated several members of the opa gene family of N. gonorrhoeae, where it has been suggested that limited variation occurs. Variation was detected in the opaK gene that is located close to pilE, but not at the opaJ gene located elsewhere on the genome. The approach described here promises to dramatically improve studies of the extent and nature of antigenic variation systems in a variety of species.

  18. BGMUT: NCBI dbRBC database of allelic variations of genes encoding antigens of blood group systems.

    Science.gov (United States)

    Patnaik, Santosh Kumar; Helmberg, Wolfgang; Blumenfeld, Olga O

    2012-01-01

    Analogous to human leukocyte antigens, blood group antigens are surface markers on the erythrocyte cell membrane whose structures differ among individuals and which can be serologically identified. The Blood Group Antigen Gene Mutation Database (BGMUT) is an online repository of allelic variations in genes that determine the antigens of various human blood group systems. The database is manually curated with allelic information collated from scientific literature and from direct submissions from research laboratories. Currently, the database documents sequence variations of a total of 1251 alleles of all 40 gene loci that together are known to affect antigens of 30 human blood group systems. When available, information on the geographic or ethnic prevalence of an allele is also provided. The BGMUT website also has general information on the human blood group systems and the genes responsible for them. BGMUT is a part of the dbRBC resource of the National Center for Biotechnology Information, USA, and is available online at http://www.ncbi.nlm.nih.gov/projects/gv/rbc/xslcgi.fcgi?cmd=bgmut. The database should be of use to members of the transfusion medicine community, those interested in studies of genetic variation and related topics such as human migrations, and students as well as members of the general public.

  19. Use of molecularly cloned avian leukosis virus to study antigenic variation following infection of meat-type chickens

    Science.gov (United States)

    A molecularly cloned strain of subgroup J avian leukosis virus (ALV-J) termed R5-4 was used to study antigenic variation following infection of meat-type chickens. Chickens were inoculated with R5-4 virus at either 8 days of embryonation or at 1 week of age. Each chicken was housed in a separate is...

  20. Leishmania-specific surface antigens show sub-genus sequence variation and immune recognition.

    Directory of Open Access Journals (Sweden)

    Daniel P Depledge

    Full Text Available BACKGROUND: A family of hydrophilic acylated surface (HASP proteins, containing extensive and variant amino acid repeats, is expressed at the plasma membrane in infective extracellular (metacyclic and intracellular (amastigote stages of Old World Leishmania species. While HASPs are antigenic in the host and can induce protective immune responses, the biological functions of these Leishmania-specific proteins remain unresolved. Previous genome analysis has suggested that parasites of the sub-genus Leishmania (Viannia have lost HASP genes from their genomes. METHODS/PRINCIPAL FINDINGS: We have used molecular and cellular methods to analyse HASP expression in New World Leishmania mexicana complex species and show that, unlike in L. major, these proteins are expressed predominantly following differentiation into amastigotes within macrophages. Further genome analysis has revealed that the L. (Viannia species, L. (V. braziliensis, does express HASP-like proteins of low amino acid similarity but with similar biochemical characteristics, from genes present on a region of chromosome 23 that is syntenic with the HASP/SHERP locus in Old World Leishmania species and the L. (L. mexicana complex. A related gene is also present in Leptomonas seymouri and this may represent the ancestral copy of these Leishmania-genus specific sequences. The L. braziliensis HASP-like proteins (named the orthologous (o HASPs are predominantly expressed on the plasma membrane in amastigotes and are recognised by immune sera taken from 4 out of 6 leishmaniasis patients tested in an endemic region of Brazil. Analysis of the repetitive domains of the oHASPs has shown considerable genetic variation in parasite isolates taken from the same patients, suggesting that antigenic change may play a role in immune recognition of this protein family. CONCLUSIONS/SIGNIFICANCE: These findings confirm that antigenic hydrophilic acylated proteins are expressed from genes in the same chromosomal

  1. Expression of P. falciparum var genes involves exchange of the histone variant H2A.Z at the promoter.

    Directory of Open Access Journals (Sweden)

    Michaela Petter

    2011-02-01

    Full Text Available Plasmodium falciparum employs antigenic variation to evade the human immune response by switching the expression of different variant surface antigens encoded by the var gene family. Epigenetic mechanisms including histone modifications and sub-nuclear compartmentalization contribute to transcriptional regulation in the malaria parasite, in particular to control antigenic variation. Another mechanism of epigenetic control is the exchange of canonical histones with alternative variants to generate functionally specialized chromatin domains. Here we demonstrate that the alternative histone PfH2A.Z is associated with the epigenetic regulation of var genes. In many eukaryotic organisms the histone variant H2A.Z mediates an open chromatin structure at promoters and facilitates diverse levels of regulation, including transcriptional activation. Throughout the asexual, intraerythrocytic lifecycle of P. falciparum we found that the P. falciparum ortholog of H2A.Z (PfH2A.Z colocalizes with histone modifications that are characteristic of transcriptionally-permissive euchromatin, but not with markers of heterochromatin. Consistent with this finding, antibodies to PfH2A.Z co-precipitate the permissive modification H3K4me3. By chromatin-immunoprecipitation we show that PfH2A.Z is enriched in nucleosomes around the transcription start site (TSS in both transcriptionally active and silent stage-specific genes. In var genes, however, PfH2A.Z is enriched at the TSS only during active transcription in ring stage parasites. Thus, in contrast to other genes, temporal var gene regulation involves histone variant exchange at promoter nucleosomes. Sir2 histone deacetylases are important for var gene silencing and their yeast ortholog antagonises H2A.Z function in subtelomeric yeast genes. In immature P. falciparum parasites lacking Sir2A or Sir2B high var transcription levels correlate with enrichment of PfH2A.Z at the TSS. As Sir2A knock out parasites mature the var

  2. Organization and variation analysis of 5S rDNA in gynogenetic offspring of Carassius auratus red var. (♀) × Megalobrama amblycephala (♂).

    Science.gov (United States)

    Qin, QinBo; Wang, Juan; Wang, YuDe; Liu, Yun; Liu, ShaoJun

    2015-03-13

    The offspring with 100 chromosomes (abbreviated as GRCC) have been obtained in the first generation of Carassius auratus red var. (abbreviated as RCC, 2n = 100) (♀) × Megalobrama amblycephala (abbreviated as BSB, 2n = 48) (♂), in which the females and unexpected males both are found. Chromosomal and karyotypic analysis has been reported in GRCC which gynogenesis origin has been suggested, but lack genetic evidence. Fluorescence in situ hybridization with species-specific centromere probes directly proves that GRCC possess two sets of RCC-derived chromosomes. Sequence analysis of the coding region (5S) and adjacent nontranscribed spacer (abbreviated as NTS) reveals that three types of 5S rDNA class (class I; class II and class III) in GRCC are completely inherited from their female parent (RCC), and show obvious base variations and insertions-deletions. Fluorescence in situ hybridization with the entire 5S rDNA probe reveals obvious chromosomal loci (class I and class II) variation in GRCC. This paper provides directly genetic evidence that GRCC is gynogenesis origin. In addition, our result is also reveals that distant hybridization inducing gynogenesis can lead to sequence and partial chromosomal loci of 5S rDNA gene obvious variation.

  3. Plasmodium falciparum associated with severe childhood malaria preferentially expresses PfEMP1 encoded by group A var genes

    DEFF Research Database (Denmark)

    Jensen, Anja T R; Magistrado, Pamela; Sharp, Sarah;

    2004-01-01

    Parasite-encoded variant surface antigens (VSAs) like the var gene-encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family are responsible for antigenic variation and infected red blood cell (RBC) cytoadhesion in P. falciparum malaria. Parasites causing severe malaria...... genes, such as PFD1235w/MAL7P1.1, appear to be involved in the pathogenesis of severe disease and are thus attractive candidates for a vaccine against life-threatening P. falciparum malaria....

  4. Variation in seed mineral elements profile and yield in field bean (Vicia faba L. var. minor genotypes

    Directory of Open Access Journals (Sweden)

    Sara Lombardo

    2016-12-01

    Full Text Available Field bean (Vicia faba L. var. minor is one of the major leguminous crops cultivated in the world and mainly destined for animal feed. Although its seed is generally recognised as a good protein source, little is known about its mineral elements profile, which is an important aspect for a balanced animal diet. Therefore, the aim of the present work was to assess the seed mineral elements composition, along with some key production parameters, in eight field bean genotypes grown in a Mediterranean environment, without intensive management, over two years (2009/10 and 2010/11. Independently of the year, the seed of Chiaro di Torre Lama was the richest in phosphorus (P, magnesium, calcium and iron contents, while that of Sint 6 and Motta Chiaro 69 were the most effective accumulators of potassium and zinc, respectively. While all the genotypes yielded better in the second year (with more rainfall, the seasonal effect on seed mineral elements composition depended on the genotype. Indeed, the P content was 46% lower in Chiaro di Torre Lama, Motta Chiaro 69 and Sint 6 in the second year, while there was only a negligible seasonal effect for Sint 8 with respect to Fe content. Overall, this crop is reasonably productive under a low management regime and its seed can supply significant amounts of certain minerals (particularly P in feed formulations. Both aspects are important in a perspective of optimising field bean production in the Mediterranean area and, hence, improving farmers’ income.

  5. Variation in Floral Sex Allocation and Reproductive Success in Sequentially Flowering Inflorescence of Corydalis remota var. lineariloba (Fumariaceae)

    Institute of Scientific and Technical Information of China (English)

    Yan-Fei Zeng; Wei-Ning Bai; Yu Zhou; Da-Yong Zhang

    2009-01-01

    In hermaphroditic plants, female reproductive success often varies among different positions within an inflorescence.However, few studies have evaluated the relative importance of underlying causes such as pollen limitation, resource limitation or architectural effect, and few have compared male allocation. During a 2-year investigation, we found that female reproductive success of an acropetally flowering species, Corydalis remota Fisch. ex Maxim. var. Iineariloba Maxim. was significantly lower in the upper late developing flowers when compared with the lower early flowers. Supplementation with outcross pollen did not improve female reproductive success of the upper flowers, while removal of the lower developing fruits significantly increased female reproductive success of the upper flowers in both years, evidencing resource limitation of the upper flowers. Female production in upper flowers was greatly improved by simultaneous pollen supplementation of the upper flowers and removal of the lower fruits, suggesting that, when resources are abundant, pollen may limit the female reproductive success of the upper flowers. The less seed mass in the upper flowers didn't increase in all treatments due to architecture. In the upper flowers, ovule production was significantly lower and the pollen : ovule ratio was significantly higher. These results suggest that male-biased sex allocation in the upper flowers may lead to increased male reproductive success, whereas the lower flowers have higher female reproductive success.

  6. Overlapping antigenic repertoires of variant antigens expressed on the surface of erythrocytes infected by Plasmodium falciparum

    DEFF Research Database (Denmark)

    Giha, H A; Staalsoe, T; Dodoo, D;

    1999-01-01

    Antibodies against variable antigens expressed on the surface of Plasmodium falciparum-infected erythrocytes are believed to be important for protection against malaria. A target for these antibodies is the P. falciparum erythrocyte membrane protein 1, PfEMP1, which is encoded by around 50 var...... genes and undergoes clonal variation. Using agglutination and mixed agglutination tests and flow cytometry to analyse the recognition of variant antigens on parasitized erythrocytes by plasma antibodies from individuals living in Daraweesh in eastern Sudan, an area of seasonal and unstable malaria...

  7. H-NS suppresses pilE intragenic transcription and antigenic variation in Neisseria gonorrhoeae.

    Science.gov (United States)

    Masters, Thao L; Wachter, Shaun; Wachter, Jenny; Hill, Stuart A

    2016-01-01

    Initially, pilE transcription in Neisseria gonorrhoeae appeared to be complicated, yet it was eventually simplified into a model where integration host factor activates a single -35/ -10 promoter. However, with the advent of high-throughput RNA sequencing, numerous small pil-specific RNAs (sense as well as antisense) have been identified at the pilE locus as well as at various pilS loci. Using a combination of in vitro transcription, site-directed mutagenesis, Northern analysis and quantitative reverse transcriptase PCR (qRT-PCR) analysis, we have identified three additional non-canonical promoter elements within the pilE gene; two are located within the midgene region (one sense and one antisense), with the third, an antisense promoter, located immediately downstream of the pilE ORF. Using strand-specific qRT-PCR analysis, an inverse correlation exists between the level of antisense expression and the amount of sense message. By their nature, promoter sequences tend to be AT-rich. In Escherichia coli, the small DNA-binding protein H-NS binds to AT-rich sequences and inhibits intragenic transcription. In N. gonorrhoeae hns mutants, pilE antisense transcription was increased twofold, with a concomitant decrease in sense transcript levels. However, most noticeably in these mutants, the absence of H-NS protein caused pilE/pilS recombination to increase dramatically when compared with WT values. Consequently, H-NS protein suppresses pilE intragenic transcription as well as antigenic variation through the pilE/pilS recombination system.

  8. Variation of expression defects in cell surface 190-kDa protein antigen of Streptococcus mutans.

    Science.gov (United States)

    Lapirattanakul, Jinthana; Nomura, Ryota; Matsumoto-Nakano, Michiyo; Srisatjaluk, Ratchapin; Ooshima, Takashi; Nakano, Kazuhiko

    2015-05-01

    Streptococcus mutans, which consists of four serotypes, c, e, f, and k, possesses a 190-kDa cell surface protein antigen (PA) for initial tooth adhesion. We used Western blot analysis to determine PA expression in 750 S. mutans isolates from 150 subjects and found a significantly higher prevalence of the isolates with PA expression defects in serotypes f and k compared to serotypes c and e. Moreover, the defect patterns could be classified into three types; no PA expression on whole bacterial cells and in their supernatant samples (Type N1), PA expression mainly seen in supernatant samples (Type N2), and only low expression of PA in the samples of whole bacterial cells (Type W). The underlying reasons for the defects were mutations in the gene encoding PA as well as in the transcriptional processing of this gene for Type N1, defects in the sortase gene for Type N2, and low mRNA expression of PA for Type W. Since cellular hydrophobicity and phagocytosis susceptibility of the PA-defective isolates were significantly lower than those of the normal expression isolates, the potential implication of such defective isolates in systemic diseases involving bacteremia other than dental caries was suggested. Additionally, multilocus sequence typing was utilized to characterize S. mutans clones that represented a proportion of isolates with PA defects of 65-100%. Therefore, we described the molecular basis for variation defects in PA expression of S. mutans. Furthermore, we also emphasized the strong association between PA expression defects and serotypes f and k as well as the clonal relationships among these isolates.

  9. O-antigen structure of Shigella flexneri serotype Yv and effect of the lpt-O gene variation on phosphoethanolamine modification of S. flexneri O-antigens.

    Science.gov (United States)

    Knirel, Yuriy A; Lan, Ruiting; Senchenkova, Sof'ya N; Wang, Jianping; Shashkov, Alexander S; Wang, Yan; Perepelov, Andrei V; Xiong, Yanwen; Xu, Jianguo; Sun, Qiangzheng

    2013-04-01

    Shigella flexneri is the major human pathogen causing shigellosis. O-antigens of all S. flexneri serotypes (except for serotype 6) share the →2)-α-l-Rhap(III)-(1 → 2)-α-l-Rhap(II)-(1 → 3)-α-l-Rhap(I)-(1 → 3)-β-d-GlcpNAc-(1→ basic O-unit, whereas differences between the serotypes are conferred by phage-encoded glucosylation and/or O-acetylation at various positions. Recently, in serotype X and 4a variants called Xv and 4av, respectively, O-antigen modification with phosphoethanolamine (PEtN) has been identified, which is encoded by a plasmid-borne gene (lpt-O) for a PEtN-transferase and confers the monoclonal antibody IV-1(MASF IV-1) determinant to the bacteria. In this study, we elucidated the O-antigen structure of serotype Yv, another MASF IV-1-positive novel variant of S. flexneri. The serotype Yv O-antigen has the same basic carbohydrate backbone structure as that of the "classical" serotype Y, but differs in the presence of PEtN at position 3 of Rha(III) (major) or both Rha(II) and Rha(III) (minor). This pattern is similar to that of serotype 4av, but different from the pattern of serotype Xv, which is characterized by major PEtN modification on Rha(II). In serotype Yv, mono- and bisphosphorylated O-units generate a block-copolymeric structure, the former being partially O-acetylated at position 6 of GlcNAc and the latter lacking O-acetylation. Functional analysis revealed a correlation between the serotype-specific PEtN modification pattern and the lpt-O variation in different serotypes: lpt-O(RII) in serotype Xv is better tuned for phosphorylation of Rha(II) and lpt-O(RIII) in serotypes Yv and 4av for phosphorylation of Rha(III). These data enhance our knowledge of S. flexneri serotype conversion mechanisms and help to understand the biosynthesis process of the new O-antigen variants.

  10. Characterization, quantification, and yearly variation of the naturally occurring polyphenols in a common red variety of curly kale ( Brassica oleracea L. convar. acephala var. sabellica cv. 'Redbor').

    Science.gov (United States)

    Olsen, Helle; Aaby, Kjersti; Borge, Grethe Iren A

    2010-11-10

    This study focuses on the characterization and quantification of polyphenols in the edible leaves of red curly kale ( Brassica oleracea L. convar. acephala (DC.) Alef. var. sabellica L.), variety 'Redbor F1 hybrid'. The kale was grown at an experimental field (59° 40' N) in the years 2007-2009. The analysis of kale extract by HPLC-DAD-ESI-MS has allowed the determination of 47 different acylated and nonacylated flavonoid glycosides and complex hydroxycinnamic acids. Those compounds included mono- to tetraglycosides of quercetin, kaempferol, and cyanidin and derivatives of p-coumaric, ferulic, sinapic, and caffeic acid. Among the compounds characterized, four flavonols, three anthocyanins, and three phenolic acids were identified in the Brassica family for the first time. Aglycones and conjugated polyphenols were quantified by HPLC-DAD using commercially available standards. The main flavonol, anthocyanin, and phenolic acid were kaempferol-3-sinapoyl-diglucoside-7-diglucoside, cyanidin-3-sinapoyl-feruloyl-diglucoside-5-glucoside, and disinapoyl-diglucoside, respectively, each representing 9.8, 10.3, and 4.9% of the total amount of 872 mg polyphenol equivalents per 100 g of fresh kale. Variations between individual plants and growing seasons were of the same order of magnitude for total phenolics and total monomeric anthocyanins.

  11. The kinetics of antibody binding to Plasmodium falciparum VAR2CSA PfEMP1 antigen and modelling of PfEMP1 antigen packing on the membrane knobs

    DEFF Research Database (Denmark)

    Joergensen, Lars M; Salanti, Ali; Dobrilovic, Tina

    2010-01-01

    ABSTRACT: BACKGROUND: Infected humans make protective antibody responses to the PfEMP1 adhesion antigens exported by Plasmodium falciparum parasites to the erythrocyte membrane, but little is known about the kinetics of this antibody-receptor binding reaction or how the topology of PfEMP1 on the ...

  12. Adjuvanted pandemic influenza vaccine: variation of emulsion components affects stability, antigen structure, and vaccine efficacy.

    Science.gov (United States)

    Fox, Christopher B; Barnes V, Lucien; Evers, Tara; Chesko, James D; Vedvick, Thomas S; Coler, Rhea N; Reed, Steven G; Baldwin, Susan L

    2013-09-01

    Adjuvant formulations are critical components of modern vaccines based on recombinant proteins, which are often poorly immunogenic without additional immune stimulants. Oil-in-water emulsions comprise an advanced class of vaccine adjuvants that are components of approved seasonal and pandemic influenza vaccines. However, few reports have been published that systematically evaluate the in vitro stability and in vivo adjuvant effects of different emulsion components. To evaluate distinct classes of surfactants, oils, and excipients, for their effects on emulsion particle size stability, antigen structural interactions, and in vivo activity when formulated with a recombinant H5N1 antigen. Emulsions were manufactured by high pressure homogenization and characterized alone or in the presence of vaccine antigen by dynamic light scattering, zeta potential, viscosity, pH, hemolytic activity, electron microscopy, fluorescence spectroscopy, and SDS-PAGE. In vivo vaccine activity in the murine model was characterized by measuring antibody titers, antibody-secreting plasma cells, hemagglutination inhibition titers, and cytokine production. We demonstrate that surfactant class and presence of additional excipients are not critical for biological activity, whereas oil structure is crucial. Moreover, we report that simplified two-component emulsions appear more stable by particle size than more complex formulations.Finally, differences in antigen structural interactions with the various emulsions do not appear to correlate with in vivo activity. Oil-in-water emulsions can significantly enhance antibody and cellular immune responses to a pandemic influenza antigen. The dramatic differences in adjuvant activity between squalene-based emulsion and medium chain triglyceride-based emulsion are due principally to the biological activity of the oil composition rather than physical interactions of the antigen with the emulsion. © 2012 John Wiley & Sons Ltd.

  13. High level of var2csa transcription by Plasmodium falciparum isolated from the placenta

    DEFF Research Database (Denmark)

    Tuikue Ndam, Nicaise G; Salanti, Ali; Bertin, Gwladys;

    2005-01-01

    Plasmodium falciparum parasites that bind to chondroitin sulphate A (CSA) express unique variant surface antigens that are involved in the placental sequestration that precipitates pregnancy-associated malaria (PAM). Two var gene subfamilies, var1csa and var2csa, have been associated with CSA bin...

  14. Variation in general practice prostate-specific antigen testing and prostate cancer outcomes

    DEFF Research Database (Denmark)

    Hjertholm, Peter; Fenger-Grøn, Morten; Vestergaard, Mogens

    2015-01-01

    Brugen af prostata-specifikt antigen (PSA) er mangedoblet i dansk almen praksis siden introduktionen i 1990’erne. Dansk Urologisk Selskab anbefaler brug af testen ved relevante symptomer og arvelig disposition, men ikke til screening. Alligevel varierer brugen af PSA-tests i almen praksis. Dette ...

  15. Variation of prostate-specific antigen expression in different tumour growth patterns present in prostatectomy specimens

    NARCIS (Netherlands)

    M.P.W. Gallee; E. Visser-de Jong (E.); J.A.G.M. van der Korput (J. A G M); Th.H. van der Kwast (Theo); F.J.W. ten Kate (Fiebo); F.H. Schröder (Fritz); J. Trapman (Jan)

    1990-01-01

    textabstractA series of 55 randomly chosen radical prostatectomy specimens was analyzed for expression of prostate-specific antigen (PSA) by immunohistochemical techniques. Tissue sections were selected in such a manner that in addition to glandular benign prostatic hyperplasia (BPH), one or more di

  16. Variation in antigenic determinants specific to the infective stage of Trypanosoma cruzi.

    Science.gov (United States)

    Wrightsman, R A; Leon, W; Manning, J E

    1986-08-01

    Monoclonal antibodies reactive with the surface antigens of the Peru strain of Trypanosoma cruzi were analyzed by Western blots and immunofluorescence assays to determine their reactivity with three life cycle stages and five strain isolates of T. cruzi. One monoclonal antibody, 7.6, recognized a 68-kilodalton (kDa) polypeptide in Western blots of Peru strain trypomastigotes, epimastigotes, and amastigotes. A 68-kDa polypeptide was also detected by monoclonal antibody 7.6 in trypomastigotes of the CL and Y strains and in the clonal isolates Esmeraldo clone 3 and Silvio X10 clone 1. Positive immunofluorescence results were obtained for all life cycle stages of the five strains that were reacted with monoclonal antibody 7.6, thus indicating that the antigen recognized by monoclonal antibody 7.6 is universally present in all T. cruzi strains tested. In contrast, monoclonal antibody 4.2 reacted with a polypeptide doublet of 90 and 105 kDa in Western blots of Peru strain trypomastigotes, but it did not detect these antigens in epimastigotes or amastigotes. The same polypeptide doublet of 90 and 105 kDa was also detected in Western blots of Y strain trypomastigotes; however, no bands were detected in blots of strain CL or isolate Silvio X10 clone 1 trypomastigotes. In blots of Esmeraldo clone 3 trypomastigotes, a single band of 130 kDa was detected by monoclonal antibody 4.2. In immunofluorescence assays of monoclonal antibody 4.2, positive reactions were obtained only with trypomastigotes of Peru, Y, and Esmeraldo clone 3 strains. Thus, monoclonal antibody 4.2 recognizes a trypomastigote-specific antigen which is not universally present on all strains of T. cruzi.

  17. Shift in S-layer protein expression responsible for antigenic variation in Campylobacter fetus.

    OpenAIRE

    Wang, E; Garcia, M M; Blake, M. S.; Pei, Z.; Blaser, M J

    1993-01-01

    Campylobacter fetus strains possess regular paracrystalline surface layers (S-layers) composed of high-molecular-weight proteins and can change the size and crystalline structure of the predominant protein expressed. Polyclonal antisera demonstrate antigenic cross-reactivity among these proteins but suggest differences in epitopes. Monoclonal antibodies to the 97-kDa S-layer protein of Campylobacter fetus subsp. fetus strain 82-40LP showed three different reactivities. Monoclonal antibody 1D1...

  18. Antigenic conservation and variation in Giardia cysts from various vertebrate hosts.

    OpenAIRE

    Riley, E T; Stibbs, H H

    1989-01-01

    Monoclonal antibodies produced against Giardia muris cysts reacted in indirect immunofluorescence with homologous cysts and cysts from a Giardia-infected wild Norway rat but did not cross-react with Giardia lamblia cysts of human, dog, or beaver sources. Another monoclonal antibody raised against Giardia simoni cysts from the Norway rat reacted with homologous cysts (rat) and cross-reacted with cysts from a cow. The demonstration of antigenic differences at the cyst surfaces of Giardia organi...

  19. Ureaplasma antigenic variation beyond MBA phase variation: DNA inversions generating chimeric structures and switching in expression of the MBA N-terminal paralogue UU172.

    Science.gov (United States)

    Zimmerman, Carl-Ulrich R; Rosengarten, Renate; Spergser, Joachim

    2011-02-01

    Phase variation of the major ureaplasma surface membrane protein, the multiple-banded antigen (MBA), with its counterpart, the UU376 protein, was recently discussed as a result of DNA inversion occurring at specific inverted repeats. Two similar inverted repeats to the ones within the mba locus were found in the genome of Ureaplasma parvum serovar 3; one within the MBA N-terminal paralogue UU172 and another in the adjacent intergenic spacer region. In this report, we demonstrate on both genomic and protein level that DNA inversion at these inverted repeats leads to alternating expression between UU172 and the neighbouring conserved hypothetical ORF UU171. Sequence analysis of this phase-variable 'UU172 element' from both U. parvum and U. urealyticum strains revealed that it is highly conserved among both species and that it also includes the orthologue of UU144. A third inverted repeat region in UU144 is proposed to serve as an additional potential inversion site from which chimeric genes can evolve. Our results indicate that site-specific recombination events in the genome of U. parvum serovar 3 are dynamic and frequent, leading to a broad spectrum of antigenic variation by which the organism may evade host immune responses.

  20. Evaluation of the Importance of VlsE Antigenic Variation for the Enzootic Cycle of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Artem S Rogovskyy

    Full Text Available Efficient acquisition and transmission of Borrelia burgdorferi by the tick vector, and the ability to persistently infect both vector and host, are important elements for the life cycle of the Lyme disease pathogen. Previous work has provided strong evidence implicating the significance of the vls locus for B. burgdorferi persistence. However, studies involving vls mutant clones have thus far only utilized in vitro-grown or host-adapted spirochetes and laboratory strains of mice. Additionally, the effects of vls mutation on tick acquisition and transmission has not yet been tested. Thus, the importance of VlsE antigenic variation for persistent infection of the natural reservoir host, and for the B. burgdorferi enzootic life cycle in general, has not been examined to date. In the current work, Ixodes scapularis and Peromyscus maniculatus were infected with different vls mutant clones to study the importance of the vls locus for the enzootic cycle of the Lyme disease pathogen. The findings highlight the significance of the vls system for long-term infection of the natural reservoir host, and show that VlsE antigenic variability is advantageous for efficient tick acquisition of B. burgdorferi from the mammalian reservoir. The data also indicate that the adaptation state of infecting spirochetes influences B. burgdorferi avoidance from host antibodies, which may be in part due to its respective VlsE expression levels. Overall, the current findings provide the most direct evidence on the importance of VlsE for the enzootic cycle of Lyme disease spirochetes, and underscore the significance of VlsE antigenic variation for maintaining B. burgdorferi in nature.

  1. Evaluation of the Importance of VlsE Antigenic Variation for the Enzootic Cycle of Borrelia burgdorferi.

    Science.gov (United States)

    Rogovskyy, Artem S; Casselli, Timothy; Tourand, Yvonne; Jones, Cami R; Owen, Jeb P; Mason, Kathleen L; Scoles, Glen A; Bankhead, Troy

    2015-01-01

    Efficient acquisition and transmission of Borrelia burgdorferi by the tick vector, and the ability to persistently infect both vector and host, are important elements for the life cycle of the Lyme disease pathogen. Previous work has provided strong evidence implicating the significance of the vls locus for B. burgdorferi persistence. However, studies involving vls mutant clones have thus far only utilized in vitro-grown or host-adapted spirochetes and laboratory strains of mice. Additionally, the effects of vls mutation on tick acquisition and transmission has not yet been tested. Thus, the importance of VlsE antigenic variation for persistent infection of the natural reservoir host, and for the B. burgdorferi enzootic life cycle in general, has not been examined to date. In the current work, Ixodes scapularis and Peromyscus maniculatus were infected with different vls mutant clones to study the importance of the vls locus for the enzootic cycle of the Lyme disease pathogen. The findings highlight the significance of the vls system for long-term infection of the natural reservoir host, and show that VlsE antigenic variability is advantageous for efficient tick acquisition of B. burgdorferi from the mammalian reservoir. The data also indicate that the adaptation state of infecting spirochetes influences B. burgdorferi avoidance from host antibodies, which may be in part due to its respective VlsE expression levels. Overall, the current findings provide the most direct evidence on the importance of VlsE for the enzootic cycle of Lyme disease spirochetes, and underscore the significance of VlsE antigenic variation for maintaining B. burgdorferi in nature.

  2. Patterns of human genetic variation inferred from comparative analysis of allelic mutations in blood group antigen genes.

    Science.gov (United States)

    Patnaik, Santosh Kumar; Blumenfeld, Olga O

    2011-03-01

    Comparative analysis of allelic variation of a gene sheds light on the pattern and process of its diversification at the population level. Gene families for which a large number of allelic forms have been verified by sequencing provide a useful resource for such studies. In this regard, human blood group-encoding genes are unique in that differences of cell surface traits among individuals and populations can be readily detected by serological screening, and correlation between the variant cell surface phenotype and the genotype is, in most cases, unequivocal. Here, we perform a comprehensive analysis of allelic forms, compiled in the Blood Group Antigen Gene Mutation database, of ABO, RHD/CE, GYPA/B/E and FUT1/2 gene families that encode the ABO, RH, MNS, and H/h blood group system antigens, respectively. These genes are excellent illustrative examples showing distinct mutational patterns among the alleles, and leading to speculation on how their origin may have been driven by recurrent but different molecular mechanisms. We illustrate how alignment of alleles of a gene may provide an additional insight into the DNA variation process and its pathways, and how this approach may serve to catalog alleles of a gene, simplifying the task and content of mutation databases.

  3. Variações na morfoanatomia foliar de Aechmea lindenii (E. Morren Baker var. lindenii (Bromeliaceae sob distintas condições ambientais Leaf morphoanatomy variation in Aechmea lindenii (E. Morren Baker var. lindenii (Bromeliaceae under distinct environmental conditions

    Directory of Open Access Journals (Sweden)

    Caroline Heinig Voltolini

    2011-03-01

    Full Text Available Aechmea lindenii (E. Morren Baker var. lindenii (Bromeliaceae-Bromelioideae ocorre em restingas e Floresta Pluvial de Encosta Atlântica em Santa Catarina e Nordeste do Rio Grande do Sul, BR. Pode ser encontrada total ou parcialmente exposta à irradiação solar e em distintas formas de vida - terrícola, rupícola e epifítica. O objetivo deste trabalho foi comparar morfoanatomicamente às características de folhas de A. lindenii var. lindenii em distintas condições ambientais. Foram coletadas, na Ilha de Santa Catarina (Florianópolis, SC, folhas de plantas terrícolas em restinga herbácea (alta irradiação solar, rupícolas de costões rochosos (alta irradiação solar, terrícolas e epifíticas de sub-bosques (baixa irradiação solar de restinga arbórea e rupícolas de sub-bosque (baixa irradiação solar de Floresta Pluvial de Encosta Atlântica. Foram mensurados comprimento, largura, área da lâmina e bainha foliar, densidade estomática, comprimento e largura das células-guarda, espessura total e das estruturas constituintes na lâmina foliar. As características anatômicas qualitativas são semelhantes nas distintas condições analisadas. A baixa irradiação solar determina maior expansão da área foliar, decorrente do alongamento da lâmina. Lâmina e bainha foliares têm maior largura sob alta irradiação. A densidade estomática foi maior em folhas de plantas sob alta irradiação solar. A espessura total da lâmina foliar foi menor em plantas terrícolas sob alta irradiação, porém não mostrou diferenças estatísticas significativas entre as outras condições.Aechmea lindenii (E. Morren Baker var. lindenii (Bromeliaceae-Bromelioideae occurs in restingas and hillside Atlantic rain forest in Santa Catarina and northeastern Rio Grande do Sul, Brazil. It is found totally or partially exposed to solar radiation and in different life forms - terricolous, rupicolous and epiphytes. The aim of this work was to compare

  4. Variations of serum carcinoembryonic antigen, alpha-fetoprotein and immunoglobulin levels in patients with breast cancer.

    Science.gov (United States)

    Vântu, A; Bălănescu, I; Stafidov, N; Voiculeţ, N

    1982-01-01

    To find the marker value of the carcinoembryonic antigen, alpha-fetoprotein (AFP) and immunoglobulin levels in patients with breast cancer, stages I or II, these parameters were determined in 94 patients devided into two groups: group A of 57 patients operated on for extirpation of the tumor without preoperative treatment and group B of 37 patients subjected to cobalto-therapy prior to operation then having the tumor extirpated. In the first group the determinations were performed before operation, at 14 days, and 2 months, respectively after the operation. In the second group 5 determinations were performed: before cobalto-therapy, after therapy, before the operation, at 15 days and 2 months, respectively after the operation. CEA and AFP were determined by the RIA tests and the immunoglobulins by immunodiffusion. The results showed that in 7 out of 37 cases the levels of CEA were significantly raised before and after therapy sometimes reaching values as high as 1000-3000 ng/nl while AFP was not influenced at all by breast tumors. The immunoglobulin values were also uninfluenced by the disease, but in certain cases of breast cancer IgA reached values of 300-500 IU/ml. It is assumed that since the patients who presented high CEA values had also an unfavourable evolution of the disease, determination of this antigen might also have a predictive value.

  5. Intraspecific epitopic variation in a carbohydrate antigen exposed on the surface of Trichostrongylus colubriformis infective L3 larvae.

    Directory of Open Access Journals (Sweden)

    David R Maass

    2009-09-01

    Full Text Available The carbohydrate larval antigen, CarLA, is present on the exposed surface of all strongylid nematode infective L3 larvae tested, and antibodies against CarLA can promote rapid immune rejection of incoming Trichostrongylus colubriformis larvae in sheep. A library of ovine recombinant single chain Fv (scFv antibody fragments, displayed on phage, was prepared from B cell mRNA of field-immune sheep. Phage displaying scFvs that bind to the surface of living exsheathed T. colubriformis L3 larvae were identified, and the majority of worm-binding scFvs recognized CarLA. Characterization of greater than 500 worm surface binding phage resulted in the identification of nine different anti-CarLA scFvs that recognized three distinct T. colubriformis CarLA epitopes based on blocking and additive ELISA. All anti-CarLA scFvs were specific to the T. colubriformis species of nematode. Each of the three scFv epitope classes displayed identical Western blot recognition patterns and recognized the exposed surface of living T. colubriformis exsheathed L3 larvae. Surprisingly, each of the anti-CarLA scFvs was able to bind to only a subset of worms. Double-labelling indirect immunofluorescence revealed that the three classes of anti-CarLA scFvs recognize distinct, non-overlapping, T. colubriformis sub-populations. These results demonstrate that individual T. colubriformis L3 larvae display only one of at least three distinct antigenic forms of CarLA on their surface at any given time, and suggest that antigenic variation within CarLA is likely a mechanism of immune evasion in strongylid nematodes.

  6. TOPO3alpha influences antigenic variation by monitoring expression-site-associated VSG switching in Trypanosoma brucei.

    Directory of Open Access Journals (Sweden)

    Hee-Sook Kim

    Full Text Available Homologous recombination (HR mediates one of the major mechanisms of trypanosome antigenic variation by placing a different variant surface glycoprotein (VSG gene under the control of the active expression site (ES. It is believed that the majority of VSG switching events occur by duplicative gene conversion, but only a few DNA repair genes that are central to HR have been assigned a role in this process. Gene conversion events that are associated with crossover are rarely seen in VSG switching, similar to mitotic HR. In other organisms, TOPO3alpha (Top3 in yeasts, a type IA topoisomerase, is part of a complex that is involved in the suppression of crossovers. We therefore asked whether a related mechanism might suppress VSG recombination. Using a set of reliable recombination and switching assays that could score individual switching mechanisms, we discovered that TOPO3alpha function is conserved in Trypanosoma brucei and that TOPO3alpha plays a critical role in antigenic switching. Switching frequency increased 10-40-fold in the absence of TOPO3alpha and this hyper-switching phenotype required RAD51. Moreover, the preference of 70-bp repeats for VSG recombination was mitigated, while homology regions elsewhere in ES were highly favored, in the absence of TOPO3alpha. Our data suggest that TOPO3alpha may remove undesirable recombination intermediates constantly arising between active and silent ESs, thereby balancing ES integrity against VSG recombination.

  7. Recent trends of antigenic variation in Bordetella pertussis isolates in Korea.

    Science.gov (United States)

    Kim, So-Hyun; Lee, Jin; Sung, Hwa Young; Yu, Jae Yon; Kim, Seong Han; Park, Mi Sun; Jung, Sang-Oun

    2014-03-01

    Pertussis is a representative vaccine-preventable disease. However, there have been recent outbreaks in countries where even higher vaccination against the disease. One reason is the emergence of antigenic variants, which are different to vaccine type. In Korea, reported cases have rapidly increased since 2009. Therefore, we analyzed genotype of strains isolated in 2011-2012 by multilocus sequence typing method. As expected, the genotype profiles of tested genes dramatically changed. The major sequence type changed from ST1 to ST2, and new sequence type (ST8) appeared. In the minimum spanning tree, recent isolates belonging to the ACC-I-ST3 subgroup were detected that were composed of ST2, ST3, and ST6. In particular, the ST2 frequency increased to 81%. The novel ST8 was linked to the increased frequency of ST2. In addition, toxic strains carrying the ptxP3 promoter type were confirmed. This ptxP3 type emerged from 2009 and its frequency had increased to 100% in 2012. Based on these results, it can be inferred that the genotypic changes in the currently circulating strains are strongly associated with the recent increasing of pertussis in Korea. Therefore, the surveillance system should be strengthened, and genetic characterization of the isolates should be expanded to the whole genome sequence level.

  8. Ureaplasma parvum serovar 3 multiple banded antigen size variation after chronic intra-amniotic infection/colonization.

    Directory of Open Access Journals (Sweden)

    James W Robinson

    Full Text Available Ureaplasma species are the microorganisms most frequently associated with adverse pregnancy outcomes. The multiple banded antigen (MBA, a surface-exposed lipoprotein, is a key virulence factor of ureaplasmas. The MBA demonstrates size variation, which we have shown previously to be correlated with the severity of chorioamnion inflammation. We aimed to investigate U. parvum serovar 3 pathogenesis in vivo, using a sheep model, by investigating: MBA variation after long term (chronic and short term (acute durations of in utero ureaplasma infections, and the severity of chorioamnionitis and inflammation in other fetal tissues. Inocula of 2 × 10(7 colony-forming-units (CFU of U. parvum serovar 3 (Up or media controls (C were injected intra-amniotically into pregnant ewes at one of three time points: day 55 (69d Up, n = 8; C69, n = 4; day 117 (7d Up, n = 8; C7, n = 2; and day 121 (3d Up, n = 8; C3, n = 2 of gestation (term = 145-150d. At day 124, preterm fetuses were delivered surgically. Samples of chorioamnion, fetal lung, and umbilical cord were: (i snap frozen for subsequent ureaplasma culture, and (ii fixed, embedded, sectioned and stained by haematoxylin and eosin stain for histological analysis. Selected fetal lung clinical ureaplasma isolates were cloned and filtered to obtain cultures from a single CFU. Passage 1 and clone 2 ureaplasma cultures were tested by western blot to demonstrate MBA variation. In acute durations of ureaplasma infection no MBA variants (3d Up or very few MBA variants (7d Up were present when compared to the original inoculum. However, numerous MBA size variants were generated in vivo (alike within contiguous tissues, amniotic fluid and fetal lung, but different variants were present within chorioamnion, during chronic, 69d exposure to ureaplasma infection. For the first time we have shown that the degree of ureaplasma MBA variation in vivo increased with the duration of gestation.

  9. Ureaplasma parvum serovar 3 multiple banded antigen size variation after chronic intra-amniotic infection/colonization.

    Science.gov (United States)

    Robinson, James W; Dando, Samantha J; Nitsos, Ilias; Newnham, John; Polglase, Graeme R; Kallapur, Suhas G; Pillow, J Jane; Kramer, Boris W; Jobe, Alan H; Payton, Diane; Knox, Christine L

    2013-01-01

    Ureaplasma species are the microorganisms most frequently associated with adverse pregnancy outcomes. The multiple banded antigen (MBA), a surface-exposed lipoprotein, is a key virulence factor of ureaplasmas. The MBA demonstrates size variation, which we have shown previously to be correlated with the severity of chorioamnion inflammation. We aimed to investigate U. parvum serovar 3 pathogenesis in vivo, using a sheep model, by investigating: MBA variation after long term (chronic) and short term (acute) durations of in utero ureaplasma infections, and the severity of chorioamnionitis and inflammation in other fetal tissues. Inocula of 2 × 10(7) colony-forming-units (CFU) of U. parvum serovar 3 (Up) or media controls (C) were injected intra-amniotically into pregnant ewes at one of three time points: day 55 (69d Up, n = 8; C69, n = 4); day 117 (7d Up, n = 8; C7, n = 2); and day 121 (3d Up, n = 8; C3, n = 2) of gestation (term = 145-150d). At day 124, preterm fetuses were delivered surgically. Samples of chorioamnion, fetal lung, and umbilical cord were: (i) snap frozen for subsequent ureaplasma culture, and (ii) fixed, embedded, sectioned and stained by haematoxylin and eosin stain for histological analysis. Selected fetal lung clinical ureaplasma isolates were cloned and filtered to obtain cultures from a single CFU. Passage 1 and clone 2 ureaplasma cultures were tested by western blot to demonstrate MBA variation. In acute durations of ureaplasma infection no MBA variants (3d Up) or very few MBA variants (7d Up) were present when compared to the original inoculum. However, numerous MBA size variants were generated in vivo (alike within contiguous tissues, amniotic fluid and fetal lung, but different variants were present within chorioamnion), during chronic, 69d exposure to ureaplasma infection. For the first time we have shown that the degree of ureaplasma MBA variation in vivo increased with the duration of gestation.

  10. Antigen-presenting genes and genomic copy number variations in the Tasmanian devil MHC

    Directory of Open Access Journals (Sweden)

    Cheng Yuanyuan

    2012-03-01

    Full Text Available Abstract Background The Tasmanian devil (Sarcophilus harrisii is currently under threat of extinction due to an unusual fatal contagious cancer called Devil Facial Tumour Disease (DFTD. DFTD is caused by a clonal tumour cell line that is transmitted between unrelated individuals as an allograft without triggering immune rejection due to low levels of Major Histocompatibility Complex (MHC diversity in Tasmanian devils. Results Here we report the characterization of the genomic regions encompassing MHC Class I and Class II genes in the Tasmanian devil. Four genomic regions approximately 960 kb in length were assembled and annotated using BAC contigs and physically mapped to devil Chromosome 4q. 34 genes and pseudogenes were identified, including five Class I and four Class II loci. Interestingly, when two haplotypes from two individuals were compared, three genomic copy number variants with sizes ranging from 1.6 to 17 kb were observed within the classical Class I gene region. One deletion is particularly important as it turns a Class Ia gene into a pseudogene in one of the haplotypes. This deletion explains the previously observed variation in the Class I allelic number between individuals. The frequency of this deletion is highest in the northwestern devil population and lowest in southeastern areas. Conclusions The third sequenced marsupial MHC provides insights into the evolution of this dynamic genomic region among the diverse marsupial species. The two sequenced devil MHC haplotypes revealed three copy number variations that are likely to significantly affect immune response and suggest that future work should focus on the role of copy number variations in disease susceptibility in this species.

  11. The contribution of chromosomal translocations to antigenic variation in Trypanosoma brucei.

    Science.gov (United States)

    Van der Ploeg, L H; Cornelissen, A W

    1984-11-13

    Genomic rearrangements influencing gene expression occur throughout nature. Several of these rearrangements disrupt normal gene expression, as exemplified by the genetic alterations caused by the mobile genetic elements of maize or Drosophila (see Shapiro 1983). Other rearrangements are part of the normal developmental programme of an organism. An understanding of the control of genomic rearrangements and their effects on gene expression should contribute to our insight into the mechanism of genetic programming and cellular development. The protozoan parasite Trypanosoma brucei exhibits a variety of genomic rearrangements that influence the expression of genes that code for versions of the variant surface glycoprotein (v.s.g.), which makes up the cell surface coat. V.s.g. genes are expressed in a mutually exclusive manner. Several v.s.g. genes are activated by duplicative transposition of the gene to a telomeric expression site where they are transcribed, while others can be activated without detectable genomic rearrangements. Recently we have been able to fractionate the chromosomes of T. brucei in agarose gels (Van der Ploeg et al. 1984 a). This led to the observations that duplicative transpositions occur inter-chromosomally and that the chromosomes of T. brucei are subject to frequent recombinations that displace hundreds of kilobase pairs. At least two and possibly more telomeric expression sites can be used for v.s.g. gene transcription. How these sites are activated and inactivated is still unsolved, but this does not depend on recombinations in the vicinity of the gene. Gross genomic rearrangements occur sometimes in correlation with antigenic switching and this suggests that such rearrangements have a function in regulating the mutually exclusive transcription of the different expression sites. V.s.g. genes consist of two exons. No physical linkage of the 35 nucleotide (n.t.) mini-exon to the v.s.g. gene main exon occurred within 15 kilobase pairs in

  12. Variations in Stable Carbon Isotope Composition and Leaf Traits of Picea schrenkiana var. tianschanica along an Altitude Gradient in Tianshan Mountains, Northwest China

    Directory of Open Access Journals (Sweden)

    Huiwen Zhang

    2014-01-01

    Full Text Available To understand the morphological and physiological responses of leaves to changes in altitudinal gradients, we examined ten morphological and physiological characteristics in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that LA, SD, LPC, and LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla + b, LDMC, LMA, and Narea varied nonlinearly with changes in altitude. With elevation below 2100 m, LNC, Narea, and Chla + b increased, while LDMC and LMA decreased with increasing altitude. When altitude was above 2100 m, these properties showed the opposite patterns. Leaf δ13C was positively correlated with Narea and LNC and negatively correlated with SD and LA, suggesting that leaf δ13C was indirectly controlled by physiological and morphological adjustments along altitudinal gradients. Based on the observed maximum values in LNC, Narea, Chla + b, and LA and the minimum values in LMA and LDMC at the elevation of 2100 m, suggesting higher photosynthetic capacity and greater potential for fast growth under superior optimum zone, we concluded that the best growing elevation for P. schrenkiana var. tianschanica in the Tianshan Mountains was approximately 2100 m.

  13. Differences in genetic variation in antigen-processing machinery components and association with cervical carcinoma risk in two Indonesian populations.

    Science.gov (United States)

    Mehta, Akash M; Spaans, Vivian M; Mahendra, Nyoman Bayu; Osse, Elisabeth M; Vet, Jessica N I; Purwoto, Gatot; Surya, I G D; Cornian, Santoso; Peters, Alexander A; Fleuren, Gert J; Jordanova, Ekaterina S

    2015-06-01

    Genetic variation of antigen-processing machinery (APM) components has been shown to be associated with cervical carcinoma risk and outcome in a genetically homogeneous Dutch population. However, the role of APM component single nucleotide polymorphisms (SNPs) in genetically heterogeneous populations with different distributions of human papillomavirus (HPV) subtypes remains unclear. Eleven non-synonymous, coding SNPs in the TAP1, TAP2, LMP2, LMP7 and ERAP1 genes were genotyped in cervical carcinoma patients and healthy controls from two distinct Indonesian populations (Balinese and Javanese). Individual genotype and allele distributions were investigated using single-marker analysis, and combined SNP effects were assessed by haplotype construction and haplotype interaction analysis. Allele distribution patterns in Bali and Java differed in relation to cervical carcinoma risk, with four ERAP1 SNPs and one TAP2 SNP in the Javanese population showing significant association with cervical carcinoma risk, while in the Balinese population, only one TAP2 SNP showed this association. Multimarker analysis demonstrated that in the Javanese patients, one specific haplotype, consisting of the ERAP1-575 locus on chromosome 5 and the TAP2-379 and TAP2-651 loci on chromosome 6, was significantly associated with cervical carcinoma risk (global P = 0.008); no significant haplotype associations were found in the Balinese population. These data indicate not only that genetic variation in APM component genes is associated with cervical carcinoma risk in Indonesia but also that the patterns of association differ depending on background genetic composition and possibly on differences in HPV type distribution.

  14. Detailed analysis of sequence changes occurring during vlsE antigenic variation in the mouse model of Borrelia burgdorferi infection.

    Directory of Open Access Journals (Sweden)

    Loïc Coutte

    2009-02-01

    Full Text Available Lyme disease Borrelia can infect humans and animals for months to years, despite the presence of an active host immune response. The vls antigenic variation system, which expresses the surface-exposed lipoprotein VlsE, plays a major role in B. burgdorferi immune evasion. Gene conversion between vls silent cassettes and the vlsE expression site occurs at high frequency during mammalian infection, resulting in sequence variation in the VlsE product. In this study, we examined vlsE sequence variation in B. burgdorferi B31 during mouse infection by analyzing 1,399 clones isolated from bladder, heart, joint, ear, and skin tissues of mice infected for 4 to 365 days. The median number of codon changes increased progressively in C3H/HeN mice from 4 to 28 days post infection, and no clones retained the parental vlsE sequence at 28 days. In contrast, the decrease in the number of clones with the parental vlsE sequence and the increase in the number of sequence changes occurred more gradually in severe combined immunodeficiency (SCID mice. Clones containing a stop codon were isolated, indicating that continuous expression of full-length VlsE is not required for survival in vivo; also, these clones continued to undergo vlsE recombination. Analysis of clones with apparent single recombination events indicated that recombinations into vlsE are nonselective with regard to the silent cassette utilized, as well as the length and location of the recombination event. Sequence changes as small as one base pair were common. Fifteen percent of recovered vlsE variants contained "template-independent" sequence changes, which clustered in the variable regions of vlsE. We hypothesize that the increased frequency and complexity of vlsE sequence changes observed in clones recovered from immunocompetent mice (as compared with SCID mice is due to rapid clearance of relatively invariant clones by variable region-specific anti-VlsE antibody responses.

  15. Immunological variation in Taenia solium porcine cysticercosis: measurement on the variation of the antibody immune response of naturally infected pigs against antigens extracted from their own cysticerci and from those of different pigs.

    Science.gov (United States)

    Ostoa-Saloma, Pedro; Esquivel-Velázquez, Marcela; Larralde, Carlos

    2013-10-18

    Although it is widely assumed that both antigen and host immunological variability are involved in the variable intensity of natural porcine infections by Taenia solium (T. solium) cysticercis and success of immunodiagnostic tests vaccines, the magnitude of such combined variability has not been studied or measured at all. In this paper we report statistical data on the variability of the antibody response of naturally infected pigs against the antigens extracted from the vesicular fluids of their own infecting cysts (variance within pigs) and against antigen samples extracted from cysts of other cysticercotic pigs (variance among pigs). The variation between pigs was greater than the inter-pigs variations, which suggests that a concomitant immunity process prevents the establishment of cysts coming from a subsequent challenge. In so doing, we found that there is not a single antigenic band that was recognized by all hosts and that antigens varied among the cysts within the same pigs as well as among pigs. Our results may be valuable for the improvement of immunodiagnostic tests and of effective vaccines against naturally acquired porcine T. solium cysticercosis.

  16. Variation in antigen-antibody affinity among serotypes of Salmonella O4 serogroup, determined using specific antisera.

    Science.gov (United States)

    Aribam, Swarmistha Devi; Elsheimer-Matulova, Marta; Matsui, Hidenori; Hirota, Jiro; Shiraiwa, Kazumasa; Ogawa, Yohsuke; Hikono, Hirokazu; Shimoji, Yoshihiro; Eguchi, Masahiro

    2015-11-01

    Serotyping is widely used for typing Salmonella during surveillance, and depends on determining the lipopolysaccharide (LPS) O-antigen and the flagellar protein (H-antigens) components. As the O-antigen is highly variable, and structurally unique to each serotype, we investigated the binding affinities of LPS from Salmonella serotypes of O4 serogroup with specific anti-antigen serum via immunoblot and enzyme-linked immunosorbent assays. Since the serotypes from O4 serogroup also express the O-antigen factor 12, O12 antiserum was also used for the analysis. LPS from the different serotypes showed different binding affinities with the antisera. Therefore, based on the antigen-antibody affinity, a modified agglutination assay was carried out by using O4 and O12 antisera. Although serotypes from O4 serogroup have the common O-antigen factors 4 and 12, the analysis showed that the degree of agglutination reaction is different for each of the serotypes. We suggest that Salmonella serogroup O4 serotypes exhibit different binding affinities with specific antisera despite the presence of common O-antigen factors 4 and 12.

  17. Putative SF2 helicases of the early-branching eukaryote Giardia lamblia are involved in antigenic variation and parasite differentiation into cysts.

    Science.gov (United States)

    Gargantini, Pablo R; Serradell, Marianela C; Torri, Alessandro; Lujan, Hugo D

    2012-11-28

    Regulation of surface antigenic variation in Giardia lamblia is controlled post-transcriptionally by an RNA-interference (RNAi) pathway that includes a Dicer-like bidentate RNase III (gDicer). This enzyme, however, lacks the RNA helicase domain present in Dicer enzymes from higher eukaryotes. The participation of several RNA helicases in practically all organisms in which RNAi was studied suggests that RNA helicases are potentially involved in antigenic variation, as well as during Giardia differentiation into cysts. An extensive in silico analysis of the Giardia genome identified 32 putative Super Family 2 RNA helicases that contain almost all the conserved RNA helicase motifs. Phylogenetic studies and sequence analysis separated them into 22 DEAD-box, 6 DEAH-box and 4 Ski2p-box RNA helicases, some of which are homologs of well-characterized helicases from higher organisms. No Giardia putative helicase was found to have significant homology to the RNA helicase domain of Dicer enzymes. Additionally a series of up- and down-regulated putative RNA helicases were found during encystation and antigenic variation by qPCR experiments. Finally, we were able to recognize 14 additional putative helicases from three different families (RecQ family, Swi2/Snf2 and Rad3 family) that could be considered DNA helicases. This is the first comprehensive analysis of the Super Family 2 helicases from the human intestinal parasite G. lamblia. The relative and variable expression of particular RNA helicases during both antigenic variation and encystation agrees with the proposed participation of these enzymes during both adaptive processes. The putatives RNA and DNA helicases identified in this early-branching eukaryote provide initial information regarding the biological role of these enzymes in cell adaptation and differentiation.

  18. Protection of palak (Beta vulgaris L. var Allgreen) plants from ozone injury by ethylenediurea (EDU): roles of biochemical and physiological variations in alleviating the adverse impacts.

    Science.gov (United States)

    Tiwari, Supriya; Agrawal, Madhoolika

    2009-06-01

    Ameliorative effects of ethylenediurea (N-[2-(2-oxo-1-imidazolinidyl) ethyl]-N' phenylurea, abbreviated as EDU) against ozone stress were studied on selected growth, biochemical, physiological and yield characteristics of palak (Beta vulgaris L. var Allgreen) plants grown in field at a suburban site of Varanasi, India. Mean eight hourly ozone concentration varied from 52 to 73 ppb which was found to produce adverse impacts on plant functioning and growth characteristics. The palak plants were treated with 300 ppm EDU at 10 days after germination at 10 days interval up to the plant maturity. Lipid peroxidation in EDU treated plants declined significantly as compared to non-EDU treated ones. Significant increment in F(v)/F(m) ratio in EDU treated plants as compared to non-EDU treated ones was recorded. EDU treated plants showed significant increment in ascorbic acid contents and reduction in peroxidase activity as compared to non-EDU treated ones. As a result of the protection provided by EDU against ozone induced stress on biochemical and physiological characteristics of palak, the morphological parameters also responded positively. Significant increments were recorded in shoot length, number of leaves plant(-1), leaf area and root and shoot biomass of EDU treated plants as compared to non-EDU treated ones. Contents of Na, K, Ca, Mg and Fe were higher in EDU treated plants as compared to non-EDU treated ones. The present investigation proves the usefulness of EDU in partially ameliorating ozone injury in ambient conditions.

  19. AntigenMap 3D: an online antigenic cartography resource.

    Science.gov (United States)

    Barnett, J Lamar; Yang, Jialiang; Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2012-05-01

    Antigenic cartography is a useful technique to visualize and minimize errors in immunological data by projecting antigens to 2D or 3D cartography. However, a 2D cartography may not be sufficient to capture the antigenic relationship from high-dimensional immunological data. AntigenMap 3D presents an online, interactive, and robust 3D antigenic cartography construction and visualization resource. AntigenMap 3D can be applied to identify antigenic variants and vaccine strain candidates for pathogens with rapid antigenic variations, such as influenza A virus. http://sysbio.cvm.msstate.edu/AntigenMap3D

  20. Vaccination-induced variation in the 140 kD merozoite surface antigen of Plasmodium knowlesi malaria

    OpenAIRE

    1987-01-01

    Immunity to 143/140 kD schizont antigens of a monkey malaria, Plasmodium knowlesi, provides partial protection to lethal malaria infection in rhesus monkeys challenged with uncloned parasites. To determine the capacity of a cloned parasite to generate variants of the 143/140 kD antigens, immunized monkeys were challenged with a clone of P. knowlesi. Parasites recovered 8 d after inoculation with a cloned parasite retained the 143/140 kD antigens. Parasites recovered 30 d after challenge had u...

  1. Structural and Functional Variation within the Alanine-Rich Repetitive Domain of Streptococcal Antigen I/II

    OpenAIRE

    Demuth, Donald R; Irvine, Douglas C.

    2002-01-01

    Members of the antigen I/II family of cell surface proteins are highly conserved, multifunctional adhesins that mediate interactions of oral streptococci with other oral bacteria, with cell matrix proteins (e.g., type I collagen), and with salivary glycoproteins, e.g., gp340. The interaction of gp340 (formerly designated salivary agglutinin) with Streptococcus mutans requires an alanine-rich repetitive domain (A region) of antigen I/II that is highly conserved in all members of this family of...

  2. The role of VlsE antigenic variation in the Lyme disease spirochete: persistence through a mechanism that differs from other pathogens.

    Science.gov (United States)

    Bankhead, Troy; Chaconas, George

    2007-09-01

    The linear plasmid, lp28-1, is required for persistent infection by the Lyme disease spirochete, Borrelia burgdorferi. This plasmid contains the vls antigenic variation locus, which has long been thought to be important for immune evasion. However, the role of the vls locus as a virulence factor during mammalian infection has not been clearly defined. We report the successful removal of the vls locus through telomere resolvase-mediated targeted deletion, and demonstrate the absolute requirement of this lp28-1 component for persistence in the mouse host. Moreover, successful infection of C3H/HeN mice with an lp28-1 plasmid in which the left portion was deleted excludes participation of other lp28-1 non-vls genes in spirochete virulence, persistence and the process of recombinational switching at vlsE. Data are also presented that cast doubt on an immune evasion mechanism whereby VlsE directly masks other surface antigens similar to what has been observed for several other pathogens that undergo recombinational antigenic variation.

  3. vsp gene expression by Giardia lamblia clone GS/M-83-H7 during antigenic variation in vivo and in vitro.

    Science.gov (United States)

    Bienz, M; Siles-Lucas, M; Wittwer, P; Müller, N

    2001-09-01

    Giardia lamblia infections are associated with antigenic variation of the parasite, which is generated by a continuous change of the variant-specific surface proteins (VSPs). Many investigations on the process of antigenic variation were based on the use of G. lamblia clone GS/M-83-H7, which expresses VSP H7 as its major surface antigen. In the present study, mice were infected with the aforementioned clonal line to investigate vsp gene expression during the complex process of antigenic variation of the parasite. Trophozoites collected from the intestines of individual animals at different time points postinfection (p.i.) were analyzed directly for their vsp gene expression patterns, i.e., without cultivating the recovered parasites in vitro. Because few trophozoites were recovered at late time points p.i., a combined 5' rapid amplification of cDNA ends-reverse transcription-PCR approach was utilized. This allowed detection and subsequent sequence analysis of vsp gene transcripts upon generation of amplified cDNA analogues. The same PCR approach was applied for analysis of vsp gene expression in variants obtained after negative selection of axenic GS/M-83-H7 trophozoites by treatment with a cytotoxic, VSP H7-specific monoclonal antibody. In an overall view of the entire panel of in vivo- and in vitro-derived parasite populations, expression of 29 different vsp gene sequences could be demonstrated. In vivo antigenic variation of G. lamblia clone GS/M-83-H7 was shown to be a continuous process involving the consecutive appearance of relatively distinct sets of vsp transcripts. During the 42-day infection period investigated, this process activated at least 22 different vsp genes. Comparative molecular analyses of the amino acid level demonstrated that all cDNA segments identified encode structural elements typical of the terminal segment of Giardia VSP. The similarity of most of the GS/M-83-H7 VSP sequences identified in the present study supports previous

  4. Variation in the cellular localization of host-protective oncospheral antigens in Taenia saginata and Taenia solium.

    Science.gov (United States)

    Jabbar, A; Verástegui, M; Lackenby, J A; Walduck, A K; Gauci, C G; Gilman, R H; Lightowlers, M W

    2010-01-01

    Immunohistochemistry and immunofluorescence with confocal microscopy were used to localize the host-protective antigens of Taenia saginata (TSA9 and TSA18) and Taenia solium (TSOL16, TSOL18 and TSOL45). In nonactivated oncospheres, TSA9 and TSOL45 antigens were found primarily in the cytoplasm of the penetration gland type one (PG1) cell. A similar pattern of staining was seen for TSOL45 in oncospheres of T. solium that remained within the oncospheral membrane. In addition, there was less intense staining of TSA9 and TSOL45 in the quadri-nucleate penetration gland type 2 (PG2) cell. TSA18, TSOL16 and TSOL18 were predominantly found in the PG2 cell. In activated oncospheres that had escaped the oncospheral membrane, the antigens (other than TSA9) were seen both in the penetration gland cell locations and throughout the oncospheral parenchyma. Co-localization analyses revealed that only TSOL16 and TSOL18 antigens were co-localized in the PG2 cell of oncospheres that had not escaped the oncospheral membrane. However, in activated oncospheres that escaped the oncospheral membrane, all three antigens of T. solium were co-localized as they were present throughout the parenchyma. No positive staining was observed on the surface of nonactivated or recently activated oncospheres of T. saginata or T. solium.

  5. Identifying Patient-Specific Epstein-Barr Nuclear Antigen-1 Genetic Variation and Potential Autoreactive Targets Relevant to Multiple Sclerosis Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Monika Tschochner

    Full Text Available Epstein-Barr virus (EBV infection represents a major environmental risk factor for multiple sclerosis (MS, with evidence of selective expansion of Epstein-Barr Nuclear Antigen-1 (EBNA1-specific CD4+ T cells that cross-recognize MS-associated myelin antigens in MS patients. HLA-DRB1*15-restricted antigen presentation also appears to determine susceptibility given its role as a dominant risk allele. In this study, we have utilised standard and next-generation sequencing techniques to investigate EBNA-1 sequence variation and its relationship to HLA-DR15 binding affinity, as well as examining potential cross-reactive immune targets within the central nervous system proteome.Sanger sequencing was performed on DNA isolated from peripheral blood samples from 73 Western Australian MS cases, without requirement for primary culture, with additional FLX 454 Roche sequencing in 23 samples to identify low-frequency variants. Patient-derived viral sequences were used to predict HLA-DRB1*1501 epitopes (NetMHCII, NetMHCIIpan and candidates were evaluated for cross recognition with human brain proteins.EBNA-1 sequence variation was limited, with no evidence of multiple viral strains and only low levels of variation identified by FLX technology (8.3% nucleotide positions at a 1% cut-off. In silico epitope mapping revealed two known HLA-DRB1*1501-restricted epitopes ('AEG': aa 481-496 and 'MVF': aa 562-577, and two putative epitopes between positions 502-543. We identified potential cross-reactive targets involving a number of major myelin antigens including experimentally confirmed HLA-DRB1*15-restricted epitopes as well as novel candidate antigens within myelin and paranodal assembly proteins that may be relevant to MS pathogenesis.This study demonstrates the feasibility of obtaining autologous EBNA-1 sequences directly from buffy coat samples, and confirms divergence of these sequences from standard laboratory strains. This approach has identified a number of

  6. Mosquito Passage Dramatically Changes var Gene Expression in Controlled Human Plasmodium falciparum Infections.

    Science.gov (United States)

    Bachmann, Anna; Petter, Michaela; Krumkamp, Ralf; Esen, Meral; Held, Jana; Scholz, Judith A M; Li, Tao; Sim, B Kim Lee; Hoffman, Stephen L; Kremsner, Peter G; Mordmüller, Benjamin; Duffy, Michael F; Tannich, Egbert

    2016-04-01

    Virulence of the most deadly malaria parasite Plasmodium falciparum is linked to the variant surface antigen PfEMP1, which is encoded by about 60 var genes per parasite genome. Although the expression of particular variants has been associated with different clinical outcomes, little is known about var gene expression at the onset of infection. By analyzing controlled human malaria infections via quantitative real-time PCR, we show that parasite populations from 18 volunteers expressed virtually identical transcript patterns that were dominated by the subtelomeric var gene group B and, to a lesser extent, group A. Furthermore, major changes in composition and frequency of var gene transcripts were detected between the parental parasite culture that was used to infect mosquitoes and Plasmodia recovered from infected volunteers, suggesting that P. falciparum resets its var gene expression during mosquito passage and starts with the broad expression of a specific subset of var genes when entering the human blood phase.

  7. 芳樟无性系叶精油及芳樟醇含量变异分析%Analysis on content variation of essential oil and linalool from leaf of Cinnamomum camphora var. linaloolifera clones

    Institute of Scientific and Technical Information of China (English)

    张国防; 于静波; 冯娟

    2012-01-01

    Essential oil content and linalool relative content in leaf of excellent individual of Cinnamomum camphora var. linaloolifera Fujita. clones and their variation states were compared. The result shows that essential oil content of the maternal plant is 1.78% and its linalool relative content is 97.56%. Average content of essential oil in leaf of the first and the second generation clones of tissue culture and their cutting clone is 1.65% , 1.60% and 1.58% with CV values of 9.09% , 7.50% and 7.59% , respectively, and average relative content of linalool in these clones is 94.32% , 94.52% and 94.60% with CV values of 0. 60% , 0. 73% and 0. 73% , respectively. There is some difference in essential oil content and linalool relative content between the first generation clone of tissue culture and the maternal plant, but the difference is small. Essential oil content and linalool relative content among these clones have no significant difference and those are stable within clones, indicating the clonal progeny can keep their parent 's good traits.

  8. Polygalacturonase production by AR2 pectinolytic bacteria through submerged fermentation of raja nangka banana peel (Musa paradisiaca var. formatypica) with variation of carbon source and pectin

    Science.gov (United States)

    Utami, R.; Widowati, E.; Ivenaria, A.; Mahajoeno, E.

    2017-04-01

    Polygalacturonase (EC 3.1.2.15) catalyzes the hydrolysis of α-1,4-glycosidic bonds on galacturonic acid. Polygalacturonase can be produced from AR2 pectinolytic bacteria isolated from orange peel and vegetable waste. Commonly cost production of enzymes were high. However, with the advancement of technology, enzymes can now be manufactured at a low cost. Production of enzymes in low cost media with agro-industrial waste is interesting. Raja nangka banana peel is agro-industrial waste that is uneconomic. Therefore, this material can be used as a pectin source in polygalacturonase production. Polygalacturonase was produced by AR2 pectinolytic bacteria with the addition of various carbon sources (1% glucose, 1% galactose, 1% lactose) and variation of pectin concentrations (5%; 7.5%; 10%). This study used submerged fermentation with a cultivation temperature of 55°C and an agitation speed of 144 rpm for a 48-h incubation time. The results showed that variation of carbon sources and pectin concentrations affected the production of polygalacturonase. After 48 h fermentation, the results showed that the number of cells of samples ranged from 8.3 to 9.445 log cells/mL; the used pectin of samples ranged from 87.170-93.745%; and the polygalacturonase activity of samples ranged from 0.030 to 0.151 U/mL. The highest polygalacturonase activity was obtained by production of polygalacturonase on 1% glucose and 10% pectin medium.

  9. Specific histone modifications play critical roles in the control of encystation and antigenic variation in the early-branching eukaryote Giardia lamblia.

    Science.gov (United States)

    Carranza, Pedro G; Gargantini, Pablo R; Prucca, César G; Torri, Alessandro; Saura, Alicia; Svärd, Staffan; Lujan, Hugo D

    2016-12-01

    During evolution, parasitic microorganisms have faced the challenges of adapting to different environments to colonize a variety of hosts. Giardia lamblia, a common cause of intestinal disease, has developed fascinating strategies to adapt both outside and inside its host's intestine, such as trophozoite differentiation into cyst and the switching of its major surface antigens. How gene expression is regulated during these adaptive processes remains undefined. Giardia lacks some typical eukaryotic features, like canonical transcription factors, linker histone H1, and complex promoter regions; suggesting that post-transcriptional and translational control of gene expression is essential for parasite survival. However, epigenetic factors may also play critical roles at the transcriptional level. Here, we describe the most common post-translational histone modifications; characterize enzymes involved in these reactions, and analyze their association with the Giardia's differentiation processes. We present evidence that NAD(+)-dependent and NAD(+)-independent histone deacetylases regulate encystation; however, a unique NAD(+)-independent histone deacetylase modulate antigenic switching. The rates of acetylation of H4K8 and H4K16 are critical for encystation, whereas a decrease in acetylation of H4K8 and methylation of H3K9 occur preferentially during antigenic variation. These results show the complexity of the mechanisms regulating gene expression in this minimalistic protozoan parasite. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Antigenic site variation in foot-and-mouth disease virus serotype O grown under vaccinal serum antibodies in vitro.

    Science.gov (United States)

    Sarangi, Laxmi N; Mohapatra, Jajati K; Subramaniam, Saravanan; Sanyal, Aniket; Pattnaik, Bramhadev

    2013-09-01

    Foot-and-mouth disease virus (FMDV) is constantly evolving under neutralizing antibody pressure in either naturally infected or vaccinated animals. This study was carried out to understand the dynamics of evolution of antigenic sites. Neutralizing antibody-resistant populations of three strains of FMDV serotype O (INDR2/1975, IND120/2002 and IND271/2001) were isolated by serial propagation in BHK-21 cells in the presence of sub-neutralizing level of bovine vaccinal sera (BVS). In the partial neutralization escape variants, fixation of aa substitutions were observed at critical residues of all established antigenic sites of serotype O {144 of VP1 (site 1), 45 and 48 of VP1 (site 3), 72 and 134 of VP2 (Site 2)} except site 4 and 5. In majority of the variant populations, site 3 was found to be substituted and therefore immunodominance may not be associated with a particular site, rather it appears to be a virus strain and infected host specific affair. Substitutions were also observed in proximity to the identified residues {41 and 51 (βB-βC loop), 133, 140 and 143 (βG-βH loop), 201, 204 and 209 (C terminus) of VP1, 71 and 75 (βB-βC loop), 131 (βE-αB region), 174 and 179 (βG-βH loop) and 219 (C terminus) of VP3} within antigenic sites of serotype O or other serotypes which could be significant in terms of neutralizing antibody binding and immune escape. Presence of similar residues in the Indian field viruses as selected in the variants supports the importance of these sites in antigenic diversification of serotype O FMD virus.

  11. Interpretation of sequential measurements of cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), and tissue polypeptide antigen (TPA) based on analytical imprecision and biological variation in the monitoring of ovarian cancer

    DEFF Research Database (Denmark)

    Tuxen, Malgorzata K.; Sölétormos, G; Petersen, P H

    2001-01-01

    patients with serological tumor markers should take into account the stochastic variation, i.e. the probability that observed increases and decreases may solely be due to analytical imprecision and normal intra-individual biological variation. The aim of this study was to provide a detailed characteristic...... that it is necessary to adjust the assessment criteria to the type of marker, and that assessment may be facilitated if based on natural logarithmic transformed concentrations....

  12. The severity of chorioamnionitis in pregnant sheep is associated with in vivo variation of the surface-exposed multiple-banded antigen/gene of Ureaplasma parvum.

    Science.gov (United States)

    Knox, Christine L; Dando, Samantha J; Nitsos, Ilias; Kallapur, Suhas G; Jobe, Alan H; Payton, Diane; Moss, Timothy J M; Newnham, John P

    2010-09-01

    Ureaplasma species are the bacteria most frequently isolated from human amniotic fluid in asymptomatic pregnancies and placental infections. Ureaplasma parvum serovars 3 and 6 are the most prevalent serovars isolated from men and women. We hypothesized that the effects on the fetus and chorioamnion of chronic ureaplasma infection in amniotic fluid are dependent on the serovar, dose, and variation of the ureaplasma multiple-banded antigen (MBA) and mba gene. We injected high- or low-dose U. parvum serovar 3, serovar 6, or vehicle intra-amniotically into pregnant ewes at 55 days of gestation (term = 150 days) and examined the chorioamnion, amniotic fluid, and fetal lung tissue of animals delivered by cesarean section at 125 days of gestation. Variation of the multiple banded antigen/mba generated by serovar 3 and serovar 6 ureaplasmas in vivo were compared by PCR assay and Western blot. Ureaplasma inoculums demonstrated only one (serovar 3) or two (serovar 6) MBA variants in vitro, but numerous antigenic variants were generated in vivo: serovar 6 passage 1 amniotic fluid cultures contained more MBA size variants than serovar 3 (P = 0.005), and ureaplasma titers were inversely related to the number of variants (P = 0.025). The severity of chorioamnionitis varied between animals. Low numbers of mba size variants (five or fewer) within amniotic fluid were associated with severe inflammation, whereas the chorioamnion from animals with nine or more mba variants showed little or no inflammation. These differences in chorioamnion inflammation may explain why not all women with in utero Ureaplasma spp. experience adverse pregnancy outcomes.

  13. The Severity of Chorioamnionitis in Pregnant Sheep Is Associated with In Vivo Variation of the Surface-Exposed Multiple-Banded Antigen/Gene of Ureaplasma parvum1

    Science.gov (United States)

    Knox, Christine L.; Dando, Samantha J.; Nitsos, Ilias; Kallapur, Suhas G.; Jobe, Alan H.; Payton, Diane; Moss, Timothy J.M.; Newnham, John P.

    2010-01-01

    Ureaplasma species are the bacteria most frequently isolated from human amniotic fluid in asymptomatic pregnancies and placental infections. Ureaplasma parvum serovars 3 and 6 are the most prevalent serovars isolated from men and women. We hypothesized that the effects on the fetus and chorioamnion of chronic ureaplasma infection in amniotic fluid are dependent on the serovar, dose, and variation of the ureaplasma multiple-banded antigen (MBA) and mba gene. We injected high- or low-dose U. parvum serovar 3, serovar 6, or vehicle intra-amniotically into pregnant ewes at 55 days of gestation (term = 150 days) and examined the chorioamnion, amniotic fluid, and fetal lung tissue of animals delivered by cesarean section at 125 days of gestation. Variation of the multiple banded antigen/mba generated by serovar 3 and serovar 6 ureaplasmas in vivo were compared by PCR assay and Western blot. Ureaplasma inoculums demonstrated only one (serovar 3) or two (serovar 6) MBA variants in vitro, but numerous antigenic variants were generated in vivo: serovar 6 passage 1 amniotic fluid cultures contained more MBA size variants than serovar 3 (P = 0.005), and ureaplasma titers were inversely related to the number of variants (P = 0.025). The severity of chorioamnionitis varied between animals. Low numbers of mba size variants (five or fewer) within amniotic fluid were associated with severe inflammation, whereas the chorioamnion from animals with nine or more mba variants showed little or no inflammation. These differences in chorioamnion inflammation may explain why not all women with in utero Ureaplasma spp. experience adverse pregnancy outcomes. PMID:20519696

  14. Identification of a Major Dimorphic Region in the Functionally Critical N-Terminal ID1 Domain of VAR2CSA

    DEFF Research Database (Denmark)

    Doritchamou, Justin; Sabbagh, Audrey; Jespersen, Jakob S;

    2015-01-01

    The VAR2CSA protein of Plasmodium falciparum is transported to and expressed on the infected erythrocyte surface where it plays a key role in placental malaria (PM). It is the current leading candidate for a vaccine to prevent PM. However, the antigenic polymorphism integral to VAR2CSA poses...

  15. CooVar: Co-occurring variant analyzer

    Directory of Open Access Journals (Sweden)

    Vergara Ismael A

    2012-11-01

    Full Text Available Abstract Background Evaluating the impact of genomic variations (GV on protein-coding transcripts is an important step in identifying variants of functional significance. Currently available programs for variant annotation depend on external databases or annotate multiple variants affecting the same transcript independently, which limits program use to organisms available in these databases or results in potentially incorrect or incomplete annotations. Findings We have developed CooVar (Co-occurring Variant Analyzer, a database-independent program for assessing the impact of GVs on protein-coding transcripts. CooVar takes GVs, reference genome sequence, and protein-coding exons as input and provides annotated GVs and transcripts as output. Other than similar programs, CooVar considers the combined impact of all GVs affecting the same transcript, generating biologically more accurate annotations. CooVar is operated from the command-line and supports standard file formats VCF, GFF/GTF, and GVF, which makes it easy to integrate into existing computational pipelines. We have extensively tested CooVar on worm and human data sets and demonstrate that it generates correct annotations in only a short amount of time. Conclusions CooVar is an easy-to-use and lightweight variant annotation tool that considers the combined impact of GVs on protein-coding transcripts. CooVar is freely available at http://genome.sfu.ca/projects/coovar/.

  16. Developmental and Genotypic Variation in Leaf Wax Content and Composition, and in Expression of Wax Biosynthetic Genes in Brassica oleracea var. capitata

    Science.gov (United States)

    Laila, Rawnak; Robin, Arif Hasan Khan; Yang, Kiwoung; Park, Jong-In; Suh, Mi Chung; Kim, Juyoung; Nou, Ill-Sup

    2017-01-01

    Cuticular waxes act as a protective barrier against environmental stresses. In the present study, we investigated developmental and genotypic variation in wax formation of cabbage lines, with a view to understand the related morphology, genetics and biochemistry. Our studies revealed that the relative expression levels of wax biosynthetic genes in the first-formed leaf of the highest-wax line remained constantly higher but were decreased in other genotypes with leaf aging. Similarly, the expression of most of the tested genes exhibited decrease from the inner leaves to the outer leaves of 5-month-old cabbage heads in the low-wax lines in contrast to the highest-wax line. In 10-week-old plants, expression of wax biosynthetic genes followed a quadratic function and was generally increased in the early developing leaves but substantially decreased at the older leaves. The waxy compounds in all cabbage lines were predominately C29-alkane, -secondary alcohol, and -ketone. Its deposition was increased with leaf age in 5-month-old plants. The high-wax lines had dense, prominent and larger crystals on the leaf surface compared to low-wax lines under scanning electron microscopy. Principal component analysis revealed that the higher expression of LTP2 genes in the lowest-wax line and the higher expression of CER3 gene in the highest-wax line were probably associated with the comparatively lower and higher wax content in those two lines, respectively. This study furthers our understanding of the relationships between the expression of wax biosynthetic genes and the wax deposition in cabbage lines. Highlight: In cabbage, expression of wax-biosynthetic genes was generally decreased in older and senescing leaves, while wax deposition was increased with leaf aging, and C29-hydrocarbon was predominant in the wax crystals. PMID:28119701

  17. Antigenic topology of the P29 surface lipoprotein of Mycoplasma fermentans: differential display of epitopes results in high-frequency phase variation.

    Science.gov (United States)

    Theiss, P; Karpas, A; Wise, K S

    1996-05-01

    Antibodies to P29, a major lipid-modified surface protein of Mycoplasma fermentans, reveal phase variation of surface epitopes occurring with high frequency in clonal lineages of the organism. This occurs despite continuous expression of the entire epitope-bearing P29 product (detected by Western immunoblotting) and contrasts with phase variation of other surface antigens mediated by differential expression of proteins. To understand the structure and antigenic topology of P29, the single-copy p29 gene from strain PG18 was cloned and sequenced. The gene encodes a prolipoprotein containing a signal sequence predicted to be modified with lipid and cleaved at the N-terminal Cys-1 residue of the mature P29 lipoprotein. The remaining 218-residue hydrophilic sequence of P29 is predicted to be located external to the single plasma membrane. Additional Cys residues at positions 91 and 128 in the mature protein were shown to form a 36-residue disulfide loop by selectively labeling sulfhydryl groups that were liberated only after chemical reduction of monomeric P29. Two nearly identical charged amino acid sequences occurred in P29, within the disulfide loop and upstream of this structure. Two distinct epitopes binding different monoclonal antibodies were associated with opposite ends of the P29 protein, by mapping products expressed in Escherichia coli from PCR-generated 3' deletion mutations of the p29 gene. Each monoclonal antibody detected high-frequency and noncoordinate changes in accessibility of the corresponding epitopes in colony immunoblots of clonal variants, yet sequencing of the p29 gene from these variants and analysis of disulfide bonds revealed no associated changes in the primary sequence or disulfide loop structure of P29. These results suggest that P29 surface epitope variation may involve masking of selected regions of P29, possibly by other surface components undergoing phase variation by differential expression. Differential masking may be an important

  18. B-cell responses to pregnancy-restricted and -unrestricted Plasmodium falciparum erythrocyte membrane protein 1 antigens in Ghanaian women naturally exposed to malaria parasites

    DEFF Research Database (Denmark)

    Ampomah, Paulina; Stevenson, Liz; Ofori, Michael F;

    2014-01-01

    Protective immunity to Plasmodium falciparum malaria acquired after natural exposure is largely antibody mediated. IgG-specific P. falciparum EMP1 (PfEMP1) proteins on the infected erythrocyte surface are particularly important. The transient antibody responses and the slowly acquired protective...... immunity probably reflect the clonal antigenic variation and allelic polymorphism of PfEMP1. However, it is likely that other immune-evasive mechanisms are also involved, such as interference with formation and maintenance of immunological memory. We measured PfEMP1-specific antibody levels by enzyme......-linked immunosorbent assay (ELISA) and memory B-cell frequencies by enzyme-linked immunosorbent spot (ELISPOT) assay in a cohort of P. falciparum-exposed nonpregnant Ghanaian women. The antigens used were a VAR2CSA-type PfEMP1 (IT4VAR04) with expression restricted to parasites infecting the placenta, as well as two...

  19. Hvem var morderen?

    DEFF Research Database (Denmark)

    Andersen, Lene Vinther

    2014-01-01

    Folkemindesamleren og forfatteren Helene Strange (1874-1943) skrev flere gange om et giftmord på en præst på Nordfalster i 1755. Hun satte spørgsmålstegn ved højesteretsdommen og hævdede, at en uskyldig pige blev dømt, mens den virkelige morder slap fri. Det var folkets uskrevne dom, som i over...

  20. Several domains from VAR2CSA can induce Plasmodium falciparum adhesion-blocking antibodies

    DEFF Research Database (Denmark)

    Salanti, Ali; Resende, Mafalda; Ditlev, Sisse B

    2010-01-01

    against a unique P. falciparum membrane protein, named VAR2CSA. This antigen is not expressed in childhood infections, since it binds chondroitin sulphate A (CSA) expressed on the intervillous space in the placenta. A vaccine appears possible because women acquire protective antibodies hindering...... sequestration in the placenta as a function of parity. A challenge for vaccine development is to design small constructs of this large antigen, which can induce broadly protective antibodies. It has previously been shown that one domain of VAR2CSA, DBL4-FCR3, induces parasite adhesion-blocking antibodies....... In this study, it is demonstrated that other domains of VAR2CSA also can induce antibodies with inhibitory activity. METHODS: All VAR2CSA domains from the 3D7 and HB3 parasites were produced in Baculovirus-transfected insect cells. Groups of three rats per protein were immunized and anti-sera were tested...

  1. Contribution of genetic variation rs266882 to prostate-specific antigen levels in healthy controls with serum PSA below 2.0 ng/ml.

    Science.gov (United States)

    Song, Jaeman; Park, Heeyoon; Lee, Gilho

    2013-04-01

    We evaluated the impact of genetic variation in the prostate-specific antigen (PSA) gene (rs266882) on serum PSA levels in healthy men as well as risk factors for benign prostate hypertrophy (BPH) and prostate cancer. The study population comprised 91 men with PSA levels below 2.0 ng/ml as healthy controls, 78 men with PSA 2-10 ng/ml as a BPH group, and 128 prostate cancer patients, all in Korea. DNA was amplified by polymerase chain reaction and the product was sequenced. We found that PSA levels were associated with a G/A polymorphism only in healthy controls. The transition, however, was not associated with PSA levels of BPH and cancer patients, nor was it a risk factor. In conclusion, this genetic factor is important for determining serum PSA levels in the naive group, whereas the disruption of prostatic architecture in BPH or prostate cancer may be a major determining factor for PSA levels.

  2. Inactivation of genes for antigenic variation in the relapsing fever spirochete Borrelia hermsii reduces infectivity in mice and transmission by ticks.

    Directory of Open Access Journals (Sweden)

    Sandra J Raffel

    2014-04-01

    Full Text Available Borrelia hermsii, a causative agent of relapsing fever of humans in western North America, is maintained in enzootic cycles that include small mammals and the tick vector Ornithodoros hermsi. In mammals, the spirochetes repeatedly evade the host's acquired immune response by undergoing antigenic variation of the variable major proteins (Vmps produced on their outer surface. This mechanism prolongs spirochete circulation in blood, which increases the potential for acquisition by fast-feeding ticks and therefore perpetuation of the spirochete in nature. Antigenic variation also underlies the relapsing disease observed when humans are infected. However, most spirochetes switch off the bloodstream Vmp and produce a different outer surface protein, the variable tick protein (Vtp, during persistent infection in the tick salivary glands. Thus the production of Vmps in mammalian blood versus Vtp in ticks is a dominant feature of the spirochete's alternating life cycle. We constructed two mutants, one which was unable to produce a Vmp and the other was unable to produce Vtp. The mutant lacking a Vmp constitutively produced Vtp, was attenuated in mice, produced lower cell densities in blood, and was unable to relapse in animals after its initial spirochetemia. This mutant also colonized ticks and was infectious by tick-bite, but remained attenuated compared to wild-type and reconstituted spirochetes. The mutant lacking Vtp also colonized ticks but produced neither Vtp nor a Vmp in tick salivary glands, which rendered the spirochete noninfectious by tick bite. Thus the ability of B. hermsii to produce Vmps prolonged its survival in blood, while the synthesis of Vtp was essential for mammalian infection by the bite of its tick vector.

  3. Swine Leukocyte Antigen-DQA Gene Variation and Its Association with Piglet Diarrhea in Large White, Landrace and Duroc.

    Science.gov (United States)

    Yang, Q L; Kong, J J; Wang, D W; Zhao, S G; Gun, S B

    2013-08-01

    The swine leukocyte antigen class II molecules are possibly associated with the induction of protective immunity. The study described here was to investigate the relationship between polymorphisms in exon 2 of the swine DQA gene and piglet diarrhea. This study was carried out on 425 suckling piglets from three purebred pig strains (Large White, Landrace and Duroc). The genetic diversity of exon 2 in swine DQA was detected by PCR-SSCP and sequencing analysis, eight unique SSCP patterns (AB, BB, BC, CC, CD, BD, BE and DD) representing five specific allele (A to E) sequences were detected. Sequence analysis revealed 21 nucleotide variable sites and resulting in 12 amino acid substitutions in the populations. A moderate level polymorphism and significant deviations from Hardy-Weinberg equilibrium of the genotypes distribution were observed in the populations (ppiglet diarrhea between different genotypes, individuals with genotype CC showed a lower diarrhea score than genotypes AB (0.98±0.09), BB (0.85±0.77) and BC (1.25±0.23) (ppiglet diarrhea.

  4. Temporal variation of Nitella furcata subsp. mucronata var. mucronata f. oligospira (Charophyceae in the Ninféias pond, São Paulo State, southeast Brazil Variação temporal de Nitella furcata subsp. mucronata var. mucronata f. oligospira (Charophyceae no Lago das Ninféias, São Paulo, sudeste do Brasil

    Directory of Open Access Journals (Sweden)

    Norma Catarina Bueno

    2006-03-01

    Full Text Available Temporal and spatial variation of Nitella furcata (Roxburgh ex Bruzelius C. Agardh emend. R.D. Wood subsp. mucronata (A. Braun R.D. Wood var. mucronata f. oligospira (A. Braun R.D. Wood were studied at the Ninféias pond (23°38'18.9"S, 46°37'16.3"W, a tropical, shallow, mesotrophic reservoir located in the Parque Estadual das Fontes do Ipiranga Biological Reserve, Municipality of São Paulo, southeast Brazil. Water samples were collected monthly from October/1996 to October/1997 for turbidity, electric conductivity, pH, alkalinity, dissolved oxygen, nutrients, biomass, and algal phenology analysis. Spatial distribution pattern of algal biomass showed that all four sampling stations were similar among themselves during the whole study period. Regarding the temporal variation, greatest algal total biomass values (98.35-266.06 g.m-2 were measured during the rainy period whereas the smallest ones (48.86-170.56 g.m-2 were detected during the dry period. Algal population density peaked at all four sampling stations from October/1996 to April/1997 (rainy period when the greatest values of air and water temperature, precipitation, solar radiation, turbidity, total nitrogen, and ammonium were measured allowing favorable conditions for the algal growth. Period from May/1997 (late fall to October/1997 (early spring was favorable to the development of reproductive structures (nucules and globules with consequent decrease of algal biomass and population density, clearly suggesting the greatest energy allocation towards the development of sexual reproductive structures. This fact was confirmed by the canonic correspondence analysis that indicated strong correlation between nucules length and width, number of nucules per plant, and oospores length and width with the low values of pH and high ones of dissolved inorganic matter detected during the dry period. Consequently, environmental factors such as increasing of water temperature and nutrients availability

  5. Variação genética, herdabilidades e ganhos na seleção para caracteres de crescimento em teste de progênies de Pinus caribaea var. bahamensis aos 20 anos de idade em Assis−SP. Genetic variation, herdabilities and gains in selection for growth traits in progeny test of Pinus caribaea var. bahamensis at 20 years of age in Assis−SP.

    Directory of Open Access Journals (Sweden)

    José Carlos Molina MAX

    2008-12-01

    Full Text Available O objetivo deste estudo foi estimarparâmetros genéticos para caracteres decrescimento em um teste de progênies de Pinuscaribaea var. bahamensis, aos 20 anos de idade.O teste de progênies foi instalado com sementes depolinização aberta provenientes de 89 árvoresmatrizes de Pinus caribaea var. bahamensis doCentro de Conservação Genética e Melhoramentode Pinheiros Tropicais - CCGMPT. Três progêniestestemunhas da mesma espécie e oito progênies deP. caribaea var. hondurensis, selecionadas emAssis para produção de resina, também foramincluídas no ensaio. O delineamento experimentalutilizado foi o látice triplo, com parcelas de dezplantas. O ensaio foi mensurado aos 20 anos deidade para diâmetro à altura do peito - DAP, alturatotal e volume real. Foram detectadas diferençassignificativas entre progênies para todos oscaracteres. A média dos caracteres para as 89progênies foi menor que a média calculada paraas testemunhas. As correlações genéticas foramaltas entre todos os caracteres (mínimog(DAPxaltura r = 0,71, P < 0,01. Foram detectados altoscoeficientes de variação genética e herdabilidadespara todos os caracteres estudados, o que mostra apossibilidade de se obter altos ganhos com a seleçãomassal e entre e dentro de progênies. Os ganhosesperados para plantios com 20 anos de idade,realizados em locais com as mesmas característicasambientais de Assis e com sementes coletadasapós a seleção no teste de progênies, foramestimados em 10,6% para DAP, 4,1% para altura,e 23,5% para volume.The aim of this study was to estimategenetic parameters for growth traits in a progenytest of Pinus caribaea var. bahamensis, at 20 yearsold. The trial was implanted using open-pollinatedseeds from 89 seed-trees of the Centro deConservação Genética e Melhoramento dePinheiros Tropicais - CCGMPT, three progenies ofthe same species selected in Assis and eightprogenies of P. caribaea var. hondurensis, alsoselected for gum yield in Assis

  6. Incremental 4D-VAR assimilation scheme based on Lorenz model

    Institute of Scientific and Technical Information of China (English)

    WANG Xidong; XU Dongfeng; XU Xiaohua

    2008-01-01

    Four-dimensional variational(4D-VAR) data assimilation method is a perfect data assimilation solution in theory, but the compu- tational issue is quite difficult in operational implementation. The incremental 4D-VAR assimilation scheme is set up in order to re- duce the computational cost. It is shown that the accuracy of the observations, the length of the assimilation window and the choice of the first guess have an important influence on the assimilation outcome through the contrast experiment. Compared with the standard 4D-VAR assimilation scheme, the incremental 4D-VAR assimilation scheme shows its advantage in the computation speed through an assimilation experiment.

  7. Identification of Hepatitis B Virus Surface Antigen (HBsAg Genotypes and Variations in Chronic Carriers from Isfahan Province, Iran

    Directory of Open Access Journals (Sweden)

    A Khedive

    2012-04-01

    Full Text Available Background: Hepatitis B virus (HBV gene and protein variations are frequently been seen in chronic patients. The aims of study were to determine the genotypes as well as the patterns of variations distribution in chronically-infected patients from the central part of Iran.Methods: The surface gene was amplified, sequenced and subsequently aligned using international and national Iranian database. Results: All strains belonged to genotype D, subgenotype D1 and subtype ayw2. Of all 62 mutations occurred at 39 nucleotide positions, 31 (50% were missense (amino acid altering and 31 (50% were silent (no amino acid changing. At the amino acid level, 30 substitutions occurred, however, 3 were in positions 122 and 127, corresponded to subtypic determination. 22 (73% out of 30 amino acid mutations occurred in different immune epitopes within surface protein, of which 12 (54.54% in B cell epitopes in 10 residues; 5 (45.45% in T helper epitopes in positions; 5 (22.73% in inside CTL epitopes in 4 residues. Conclusion: The distribution of amino acid mutations as well as the ratio between silent and missense nucleotide mutations showed a narrowly focused immune pressure had already been on the surface protein in these patients, led to the emergence of escape mutants in these patients.

  8. Antigenic Variation of East/Central/South African and Asian Chikungunya Virus Genotypes in Neutralization by Immune Sera

    Science.gov (United States)

    Chua, Chong-Long; Sam, I-Ching; Merits, Andres; Chan, Yoke-Fun

    2016-01-01

    Background Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus which causes epidemics of fever, severe joint pain and rash. Between 2005 and 2010, the East/Central/South African (ECSA) genotype was responsible for global explosive outbreaks across India, the Indian Ocean and Southeast Asia. From late 2013, Asian genotype CHIKV has caused outbreaks in the Americas. The characteristics of cross-antibody efficacy and epitopes are poorly understood. Methodology/Principal Findings We characterized human immune sera collected during two independent outbreaks in Malaysia of the Asian genotype in 2006 and the ECSA genotype in 2008–2010. Neutralizing capacity was analyzed against representative clinical isolates as well as viruses rescued from infectious clones of ECSA and Asian CHIKV. Using whole virus antigen and recombinant E1 and E2 envelope glycoproteins, we further investigated antibody binding sites, epitopes, and antibody titers. Both ECSA and Asian sera demonstrated stronger neutralizing capacity against the ECSA genotype, which corresponded to strong epitope-antibody interaction. ECSA serum targeted conformational epitope sites in the E1-E2 glycoprotein, and E1-E211K, E2-I2T, E2-H5N, E2-G118S and E2-S194G are key amino acids that enhance cross-neutralizing efficacy. As for Asian serum, the antibodies targeting E2 glycoprotein correlated with neutralizing efficacy, and I2T, H5N, G118S and S194G altered and improved the neutralization profile. Rabbit polyclonal antibody against the N-terminal linear neutralizing epitope from the ECSA sequence has reduced binding capacity and neutralization efficacy against Asian CHIKV. These findings imply that the choice of vaccine strain may impact cross-protection against different genotypes. Conclusion/Significance Immune serum from humans infected with CHIKV of either ECSA or Asian genotypes showed differences in binding and neutralization characteristics. These findings have implications for the continued

  9. Variation.

    Science.gov (United States)

    Hamilton City Board of Education (Ontario).

    Suggestions for studying the topic of variation of individuals and objects (balls) to help develop elementary school students' measurement, comparison, classification, evaluation, and data collection and recording skills are made. General suggestions of variables that can be investigated are made for the study of human variation. Twelve specific…

  10. Development and evaluation of a high-resolution reanalysis of the East Australian Current region using the Regional Ocean Modelling System (ROMS 3.4) and Incremental Strong-Constraint 4-Dimensional Variational (IS4D-Var) data assimilation

    Science.gov (United States)

    Kerry, Colette; Powell, Brian; Roughan, Moninya; Oke, Peter

    2016-10-01

    As with other Western Boundary Currents globally, the East Australian Current (EAC) is highly variable making it a challenge to model and predict. For the EAC region, we combine a high-resolution state-of-the-art numerical ocean model with a variety of traditional and newly available observations using an advanced variational data assimilation scheme. The numerical model is configured using the Regional Ocean Modelling System (ROMS 3.4) and takes boundary forcing from the BlueLink ReANalysis (BRAN3). For the data assimilation, we use an Incremental Strong-Constraint 4-Dimensional Variational (IS4D-Var) scheme, which uses the model dynamics to perturb the initial conditions, atmospheric forcing, and boundary conditions, such that the modelled ocean state better fits and is in balance with the observations. This paper describes the data assimilative model configuration that achieves a significant reduction of the difference between the modelled solution and the observations to give a dynamically consistent "best estimate" of the ocean state over a 2-year period. The reanalysis is shown to represent both assimilated and non-assimilated observations well. It achieves mean spatially averaged root mean squared (rms) residuals with the observations of 7.6 cm for sea surface height (SSH) and 0.4 °C for sea surface temperature (SST) over the assimilation period. The time-mean rms residual for subsurface temperature measured by Argo floats is a maximum of 0.9 °C between water depths of 100 and 300 m and smaller throughout the rest of the water column. Velocities at several offshore and continental shelf moorings are well represented in the reanalysis with complex correlations between 0.8 and 1 for all observations in the upper 500 m. Surface radial velocities from a high-frequency radar array are assimilated and the reanalysis provides surface velocity estimates with complex correlations with observed velocities of 0.8-1 across the radar footprint. A comparison with

  11. Structural and functional insight into how the Plasmodium falciparum VAR2CSA protein mediates binding to chondroitin sulfate A in placental malaria

    DEFF Research Database (Denmark)

    Clausen, Thomas M; Christoffersen, Stig; Dahlbäck, Madeleine

    2012-01-01

    Malaria is a major global health problem. Pregnant women are susceptible to infection regardless of previously acquired immunity. Placental malaria is caused by parasites capable of sequestering in the placenta. This is mediated by VAR2CSA, a parasite antigen that interacts with chondroitin sulfa......-function studies, we have constructed a small VAR2CSA antigen that has the capacity to induce highly adhesion-blocking antibodies....

  12. var. puiggarianum (Batrachospermales, Rhodophyta

    Directory of Open Access Journals (Sweden)

    María Cecilia Gauna

    2005-01-01

    Full Text Available Se coleccionó Batrachospermum atrum var. puiggarianum por primera vez en la provincia de Buenos Aires. La identificación de las muestras se basó en el análisis de la morfología microscópica y en el número cromosómico de cada una de las generaciones de su ciclo de vida bajo cultivo. Los talos se estudiaron con microscopio óptico, y la cariología, por medio de la técnica de carmín acético. El ciclo de vida presentó tres generaciones: una gametofítica haploide, una carposporófitica diploide que originó la última fase Chantransia diploide. Los talos gametófitos estuvieron formados por verticilos separados por zonas internodales, cada uno de ellos constituidos por ramas primarias densamente comprimidas. Entre éstas se observaron ramas portadoras de espermatangios y de carpogonios. Las zonas internodales estuvieron constituidas por células corticales y axiales. Los carposporófitos ovoideos estuvieron formados por filamentos gonimoblásticos portadores de carposporangios terminales. El estado Chantransia se caracterizó por presentar filamentos cortos con pocas células. El material estudiado presentó un número haploide n = 4 y diploide 2n = 8.

  13. Induction of adhesion-inhibitory antibodies against placental Plasmodium falciparum parasites by using single domains of VAR2CSA

    DEFF Research Database (Denmark)

    Nielsen, Morten A; Pinto, Vera V; Resende, Mafalda

    2009-01-01

    between a parasite protein expressed on erythrocytes named variant surface antigen 2-chondroitin sulfate A (VAR2CSA) and CSA on syncytiotrophoblasts. VAR2CSA is a large polymorphic protein consisting of six Duffy binding-like (DBL), domains and with current constraints on recombinant protein production...... which induce antibodies that inhibit CSA binding of different parasite strains. In this study, we produced a large panel of VAR2CSA proteins and raised antibodies against these antigens. We show that antibodies against the DBL4 domain effectively inhibit parasite binding. As the inhibition...... was not limited to homologous parasite strains, it seems feasible to base a protective malaria vaccine on a single VAR2CSA DBL domain....

  14. VAR, SVAR and SVEC Models: Implementation Within R Package vars

    Directory of Open Access Journals (Sweden)

    Bernhard Pfaff

    2008-02-01

    Full Text Available The structure of the package vars and its implementation of vector autoregressive, structural vector autoregressive and structural vector error correction models are explained in this paper. In addition to the three cornerstone functions VAR(, SVAR( and SVEC( for estimating such models, functions for diagnostic testing, estimation of a restricted models, prediction, causality analysis, impulse response analysis and forecast error variance decomposition are provided too. It is further possible to convert vector error correction models into their level VAR representation. The different methods and functions are elucidated by employing a macroeconomic data set for Canada. However, the focus in this writing is on the implementation part rather than the usage of the tools at hand.

  15. Comparison between 3D-Var and 4D-Var data assimilation methods for the simulation of a heavy rainfall case in central Italy

    Science.gov (United States)

    Mazzarella, Vincenzo; Maiello, Ida; Capozzi, Vincenzo; Budillon, Giorgio; Ferretti, Rossella

    2017-08-01

    This work aims to provide a comparison between three dimensional and four dimensional variational data assimilation methods (3D-Var and 4D-Var) for a heavy rainfall case in central Italy. To evaluate the impact of the assimilation of reflectivity and radial velocity acquired from Monte Midia Doppler radar into the Weather Research Forecasting (WRF) model, the quantitative precipitation forecast (QPF) is used.The two methods are compared for a heavy rainfall event that occurred in central Italy on 14 September 2012 during the first Special Observation Period (SOP1) of the HyMeX (HYdrological cycle in Mediterranean EXperiment) campaign. This event, characterized by a deep low pressure system over the Tyrrhenian Sea, produced flash floods over the Marche and Abruzzo regions, where rainfall maxima reached more than 150 mm 24 h-1.To identify the best QPF, nine experiments are performed using 3D-Var and 4D-Var data assimilation techniques. All simulations are compared in terms of rainfall forecast and precipitation measured by the gauges through three statistical indicators: probability of detection (POD), critical success index (CSI) and false alarm ratio (FAR). The assimilation of conventional observations with 4D-Var method improves the QPF compared to 3D-Var. In addition, the use of radar measurements in 4D-Var simulations enhances the performances of statistical scores for higher rainfall thresholds.

  16. Bovine leukocyte antigen major histocompatibility complex class II DRB3*2703 and DRB3*1501 alleles are associated with variation in levels of protection against Theileria parva challenge following immunization with the sporozoite p67 antigen.

    Science.gov (United States)

    Ballingall, Keith T; Luyai, Anthony; Rowlands, G John; Sales, Jill; Musoke, Anthony J; Morzaria, Subash P; McKeever, Declan J

    2004-05-01

    Initial laboratory trials of an experimental subunit vaccine against Theileria parva based on the 67-kDa major sporozoite surface antigen revealed a range of responses to challenge. We have analyzed convergence in seven sets of monozygotic twins which suggests that genetic factors may have an influence in determining the degree of protection provided by p67 immunization. In addition, we have examined whether allelic diversity at major histocompatibility complex class II loci influences protection. Analysis of bovine leukocyte antigen DRB3 diversity in 201 animals identified significant associations with vaccine success (DRB3*2703; P = 0.027) and vaccine failure (DRB3*1501; P = 0.013). Furthermore, DRB3*2703 was associated with the likelihood of immunized animals showing little to no clinical signs of disease following challenge. We discuss the acquired and innate immune mechanisms that may be behind the associations described here.

  17. Identification of bovine leukocyte antigen class II haplotypes associated with variations in bovine leukemia virus proviral load in Japanese Black cattle.

    Science.gov (United States)

    Miyasaka, T; Takeshima, S-n; Jimba, M; Matsumoto, Y; Kobayashi, N; Matsuhashi, T; Sentsui, H; Aida, Y

    2013-02-01

    Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis, which is the most common neoplastic disease of cattle. Bovine leukocyte antigen (BoLA) is strongly involved in the subclinical progression of BLV infections. Recent studies show that the BoLA-DRB3 gene might play a direct role in controlling the number of BLV-infected peripheral B lymphocytes in vivo in Holstein cattle. However, the specific BoLA class II allele and DRB3-DQA1 haplotypes determining the BLV proviral load in Japanese Black cattle are yet to be identified. In this study, we focused on the association of BLV proviral load and polymorphism of BoLA class II in Japanese Black cattle. We genotyped 186 BLV-infected, clinically normal cattle for BoLA-DRB3 and BoLA-DQA1 using a polymerase chain reaction-sequence-based typing method. BoLA-DRB3*0902 and BoLA-DRB3*1101 were associated with a low proviral load (LPVL), and BoLA-DRB3*1601 was associated with a high proviral load (HPVL). Furthermore, BoLA-DQA1*0204 and BoLA-DQA1*10012 were related to LPVL and HPVL, respectively. Furthermore, we confirmed the correlation between the DRB3-DQA1 haplotype and BLV proviral load. Two haplotypes, namely 0902B or C (DRB3*0902-DQA1*0204) and 1101A (DRB3*1101-DQA1*10011), were associated with a low BLV proviral load, whereas one haplotype 1601B (DRB3*1601-DQA1*10012) was associated with a high BLV proviral load. We conclude that resistance is a dominant trait and susceptibility is a recessive trait. Additionally, resistant alleles were common between Japanese Black and Holstein cattle, and susceptible alleles differed. This is the first report to identify an association between the DRB3-DQA1 haplotype and variations in BLV proviral load.

  18. Optimizing expression of the pregnancy malaria vaccine candidate, VAR2CSA in Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Narum David L

    2009-06-01

    Full Text Available Abstract Background VAR2CSA is the main candidate for a vaccine against pregnancy-associated malaria, but vaccine development is complicated by the large size and complex disulfide bonding pattern of the protein. Recent X-ray crystallographic information suggests that domain boundaries of VAR2CSA Duffy binding-like (DBL domains may be larger than previously predicted and include two additional cysteine residues. This study investigated whether longer constructs would improve VAR2CSA recombinant protein secretion from Pichia pastoris and if domain boundaries were applicable across different VAR2CSA alleles. Methods VAR2CSA sequences were bioinformatically analysed to identify the predicted C11 and C12 cysteine residues at the C-termini of DBL domains and revised N- and C-termimal domain boundaries were predicted in VAR2CSA. Multiple construct boundaries were systematically evaluated for protein secretion in P. pastoris and secreted proteins were tested as immunogens. Results From a total of 42 different VAR2CSA constructs, 15 proteins (36% were secreted. Longer construct boundaries, including the predicted C11 and C12 cysteine residues, generally improved expression of poorly or non-secreted domains and permitted expression of all six VAR2CSA DBL domains. However, protein secretion was still highly empiric and affected by subtle differences in domain boundaries and allelic variation between VAR2CSA sequences. Eleven of the secreted proteins were used to immunize rabbits. Antibodies reacted with CSA-binding infected erythrocytes, indicating that P. pastoris recombinant proteins possessed native protein epitopes. Conclusion These findings strengthen emerging data for a revision of DBL domain boundaries in var-encoded proteins and may facilitate pregnancy malaria vaccine development.

  19. Research Progress on the Mechanisms of Antigenic Variation in Giardia lamblia%蓝氏贾第鞭毛虫表面抗原变异机制研究进展

    Institute of Scientific and Technical Information of China (English)

    冯宪敏; 王月华; 鞠晓红

    2012-01-01

    蓝氏贾第鞭毛虫(Giardia lamblia,简称贾第虫)是引起腹泻的最常见的肠道寄生原虫之一.同大多数肠道寄生的病原体一样,表面抗原(variant-specific surface proteins,VSPs)变异是虫体逃避宿主免疫攻击的重要机制,从而导致疾病慢性化和/或重复感染的发生.本文将从基因水平的调控、转录和转录后调控、VSPs表达修饰调节和VSPs的加工、处理与转运等4个方面对贾第虫表面抗原变异机制的研究进展进行综述.%The intestinal protozoan parasite Giardia lamblia is one of the most common causes of diarrhoea and undergoes antigenic variation. In pathogenic microorganisms, antigenic variation is often described as a mechanism to evade the host immune system, resulting in chronic and/or recurrent infections. In the recent years, significant advances in the knowledge of the antigen switching process have been achieved. Here we review the principal knowledge on the mechanisms that regulate this process, including genomic organization, post-tanscriptional gene silencing, expressional modifications, and processing and turnover of VSPs.

  20. Influence of intermittent preventive treatment on antibodies to VAR2CSA in pregnant Cameroonian women

    DEFF Research Database (Denmark)

    Babakhanyan, Anna; Tutterrow, Yeung L; Bobbili, Naveen;

    2016-01-01

    Intermittent preventive treatment (IPT) and insecticide-treated bed nets are the standard of care for preventing malaria in pregnant women. Since these preventive measures reduce exposure to malaria, their influence on the antibody (Ab) response to the parasite antigen VAR2CSA was evaluated...... in pregnant Cameroonian women exposed to holoendemic malaria. Ab levels to full-length VAR2CSA (FV2), variants of the six Duffy binding like (DBL) domains, and proportion of high avidity Ab to FV2 were measured longitudinally in 92 women before and 147 women after IPT. As predicted, reduced exposure...

  1. Clinical significance of variations in levels of Epstein-Barr Virus (EBV) antigen and adaptive immune response during chronic active EBV infection in children.

    Science.gov (United States)

    Xing, Yan; Song, Hong Mei; Wei, Min; Liu, Yu; Zhang, Yu Hua; Gao, Li

    2013-01-01

    Pediatric patients were recruited to analyze differences in Epstein-Barr virus (EBV) copy numbers and adaptive immune reactions in children with chronic active vs acute EBV infection (CAEBVI vs AEBVI), as well as to examine the relationship between these parameters and the pathogenesis of CAEBVI. Fluorescent qPCR was used to assess EBV-DNA levels, while ELISA, antibody affinity, flow cytometry, and heterophil agglutination (HA) assays were used to evaluate patient EBV-adaptive humoral and cellular immunity. Lastly, ELISPOT was employed to assess interferon (IFN)-γ secretory functions of EBV-specific cytotoxic T-lymphocytes (CTL) as a marker of subject EBV-specific adaptive cellular immunity. The results indicated that, compared with AEBVI patients or normal children, there was a dramatic elevation in viral copy levels, viral capsid antigen (VCA)-IgA, early antigen (EA)-IgA, and EA-IgG, but a lack of EBV nuclear antigen (EBNA)-IgG and a negative HA in CAEBVI patients (p EBV-specific CTL function compared with normal children (p EBV antigen availability and in both the adaptive humoral and cellular immune responses in patients with CAEBVI, and that these outcomes may be associated with the chronic active re-infection process itself associated with CAEBVI.

  2. Antigenic variation of clade 2.1 H5N1 virus is determined by a few amino acid substitutions immediately adjacent to the receptor binding site

    NARCIS (Netherlands)

    B.F. Koel (Björn); S. van der Vliet (Stefan); D.F. Burke (David); T.M. Bestebroer (Theo); E.E. Bharoto (Eny); I.W.W. Yasa (I. Wayan); I. Herliana (Inna); B.M. Laksono (Brigitta); K. Xu (Kemin); E. Skepner (Eugene); C.A. Russell (Colin); G.F. Rimmelzwaan (Guus); D.R. Perez (Daniel); A.D.M.E. Osterhaus (Albert); D.J. Smith (Derek James); T.Y. Prajitno (Teguh); R.A.M. Fouchier (Ron)

    2014-01-01

    textabstractHighly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype are genetically highly variable and have diversified into multiple phylogenetic clades over the past decade. Antigenic drift is a well-studied phenomenon for seasonal human influenza viruses, but much less is known abou

  3. Bacillus cereus var. toyoi enhanced systemic immune response in piglets.

    Science.gov (United States)

    Schierack, Peter; Wieler, Lothar H; Taras, David; Herwig, Volker; Tachu, Babila; Hlinak, Andreas; Schmidt, Michael F G; Scharek, Lydia

    2007-07-15

    Probiotic bacteria have been suggested to stimulate the host immune system. In this study we evaluated the immunomodulatory effects of probiotic Bacillus cereus var. toyoi on the systemic immunity of piglets. A pool of 70 piglets was divided into a probiotic or control group. We determined the ratios of peripheral blood mononuclear cell (PBMC) subsets and measured proliferative responses and cytokine production of PBMCs and effects on vaccination responses. Blood samples of probiotic-treated piglets showed a significantly lower frequency of CD8(high)/CD3+ T cells and CD8(low)/CD3+ T cells and a significant higher CD4+/CD8+ ratio. IL-4 and IFN-gamma production of polyclonally stimulated PBMCs was on average higher in the probiotic group. Specific proliferative responses of PBMCs to Influenza vaccination antigens were significantly higher and antibody titers against H3N2 Influenza and Mycoplasma vaccination antigens were on average higher in the probiotic group. In conclusion, B. cereus var. toyoi therefore alters the immune status of piglets as indicated by changes in the ratios as well as functionalities of systemic immune cell populations.

  4. Feasibility of Stochastic Voltage/VAr Optimization Considering Renewable Energy Resources for Smart Grid

    Science.gov (United States)

    Momoh, James A.; Salkuti, Surender Reddy

    2016-06-01

    This paper proposes a stochastic optimization technique for solving the Voltage/VAr control problem including the load demand and Renewable Energy Resources (RERs) variation. The RERs often take along some inputs like stochastic behavior. One of the important challenges i. e., Voltage/VAr control is a prime source for handling power system complexity and reliability, hence it is the fundamental requirement for all the utility companies. There is a need for the robust and efficient Voltage/VAr optimization technique to meet the peak demand and reduction of system losses. The voltages beyond the limit may damage costly sub-station devices and equipments at consumer end as well. Especially, the RERs introduces more disturbances and some of the RERs are not even capable enough to meet the VAr demand. Therefore, there is a strong need for the Voltage/VAr control in RERs environment. This paper aims at the development of optimal scheme for Voltage/VAr control involving RERs. In this paper, Latin Hypercube Sampling (LHS) method is used to cover full range of variables by maximally satisfying the marginal distribution. Here, backward scenario reduction technique is used to reduce the number of scenarios effectively and maximally retain the fitting accuracy of samples. The developed optimization scheme is tested on IEEE 24 bus Reliability Test System (RTS) considering the load demand and RERs variation.

  5. Fast Responding Voltage Regulator and Dynamic VAR Compensator

    Energy Technology Data Exchange (ETDEWEB)

    Divan, Deepak [Varentec, Incorporated, San Jose, CA (United States); Moghe, Rohit [Varentec, Incorporated, San Jose, CA (United States); Tholomier, Damien [Varentec, Incorporated, San Jose, CA (United States)

    2014-12-31

    The objectives of this project were to develop a dynamic VAR compensator (DVC) for voltage regulation through VAR support to demonstrate the ability to achieve greater levels of voltage control on electricity distribution networks, and faster response compared to existing grid technology. The goal of the project was to develop a prototype Fast Dynamic VAR Compensator (Fast DVC) hardware device, and this was achieved. In addition to developing the dynamic VAR compensator device, Varentec in partnership with researchers at North Carolina State University (NCSU) successfully met the objectives to model the potential positive impact of such DVCs on representative power networks. This modeling activity validated the ability of distributed dynamic VAR compensators to provide fast voltage regulation and reactive power control required to respond to grid disturbances under high penetration of fluctuating and intermittent distributed energy resources (DERs) through extensive simulation studies. Specifically the following tasks were set to be accomplished: 1) Development of dynamic VAR compensator to support dynamic voltage variations on the grid through VAR control 2) Extensive testing of the DVC in the lab environment 3) Present the operational DVC device to the DOE at Varentec’s lab 4) Formulation of a detailed specification sheet, unit assembly document, test setup document, unit bring-up plan, and test plan 5) Extensive simulations of the DVC in a system with high PV penetration. Understanding the operation with many DVC on a single distribution system 6) Creation and submittal of quarterly and final reports conveying the design documents, unit performance data, modeling simulation charts and diagrams, and summary explanations of the satisfaction of program goals. This report details the various efforts that led to the development of the Fast DVC as well as the modeling & simulation results. The report begins with the introduction in Section II which outlines the

  6. Release Variation of Volatile Compounds from Pinus sylvestnis var.mongolica Litv.and Their Effects on Bacteri-ostasis%樟子松挥发性有机物释放动态及其抑菌作用

    Institute of Scientific and Technical Information of China (English)

    郭阿君; 王志英; 邹丽

    2014-01-01

    利用SUMMA采样罐收集樟子松( Pinus sylvestnis var.mongolica Litv.)挥发物,通过预浓缩仪与气质联用系统对樟子松挥发物进行分析。研究结果表明:春、夏、秋三季樟子松挥发物的主要成分有萜类、烷烃、烯烃类、醇类、呋喃类、醛类、酮类和含氮化合物7大类物质,其中萜类、烃类物质占主体,且随季节变化显著。(+)-2-蒈烯(占挥发物总量36.84%)、(+)-莰烯(占挥发物总量22.28%)是构成春季挥发物的主要成分,夏季则以2-氯-1-丙烯(占挥发物总量34.31%)为主,秋季以(E)-2,7-二甲基-3-辛烯-5-炔(占挥发物总量59.19%)、桧烯(占挥发物总量11.35%)、莰烯(占挥发物总量9.05%)、β-蒎烯(占挥发物总量6.88%)、β-月桂烯(占挥发物总量4.01%)为主。樟子松的挥发物对空气中的细菌具有抑制作用,以夏季抑菌作用最强。%Pre-concentrated system combined with GC-MS was evaluated for determining volatile compounds from Pinus sylvestnis var.mongolica Litv.by SUMMA canister for sampling.In spring, summer and autumn, the main compounds of volatile compounds are terpene, alkenes, alkanes, alcohol, furan, aldehydes, ketone and nitrogenous compounds, and the ter-pene, alkenes and alkanes are major component.The component and content have dynamic varieties in different seasons. (+)-2-caren (36.84%) and (+)-Camphene (22.28%) are major component in spring, 1-Propene, 2-chloro-(34.31%) in summer, and 3-Octen-5-yne,2,7-dimethyl-(E)-(59.19%), sabinene (11.35%), camphene (9.05%) and beta.-Pi-nene (6.88%) inautumn .Volatile compounds from Pinsu sylvestnis var.mongolica Litv.have inhibition against bacteria in air especially in summer.

  7. Recovery Plan for Chamaesyce Skottsbergii var. Skottsbergi and Achranthes Splendens var. Rotundata

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is the completed recovery plan for Chamaesyce Skottsbergii var. Skottsbergii and Achymnthes Splendens var. Rotunpata. It delineates reasonable actions that are...

  8. Differential induction of functional IgG using the Plasmodium falciparum placental malaria vaccine candidate VAR2CSA

    DEFF Research Database (Denmark)

    Pinto, Vera V; Ditlev, Sisse B; Jensen, Kamilla E

    2011-01-01

    In Plasmodium falciparum malaria endemic areas placental malaria (PM) is an important complication of malaria. The recurrence of malaria in primigravidae women irrespective of acquired protection during childhood is caused by the interaction between the parasite-expressed VAR2CSA antigen...

  9. A comparison between EDA-EnVar and ETKF-EnVar data assimilation techniques using radar observations at convective scales through a case study of Hurricane Ike (2008)

    Science.gov (United States)

    Shen, Feifei; Xu, Dongmei; Xue, Ming; Min, Jinzhong

    2017-07-01

    This study examines the impacts of assimilating radar radial velocity (Vr) data for the simulation of hurricane Ike (2008) with two different ensemble generation techniques in the framework of the hybrid ensemble-variational (EnVar) data assimilation system of Weather Research and Forecasting model. For the generation of ensemble perturbations we apply two techniques, the ensemble transform Kalman filter (ETKF) and the ensemble of data assimilation (EDA). For the ETKF-EnVar, the forecast ensemble perturbations are updated by the ETKF, while for the EDA-EnVar, the hybrid is employed to update each ensemble member with perturbed observations. The ensemble mean is analyzed by the hybrid method with flow-dependent ensemble covariance for both EnVar. The sensitivity of analyses and forecasts to the two applied ensemble generation techniques is investigated in our current study. It is found that the EnVar system is rather stable with different ensemble update techniques in terms of its skill on improving the analyses and forecasts. The EDA-EnVar-based ensemble perturbations are likely to include slightly less organized spatial structures than those in ETKF-EnVar, and the perturbations of the latter are constructed more dynamically. Detailed diagnostics reveal that both of the EnVar schemes not only produce positive temperature increments around the hurricane center but also systematically adjust the hurricane location with the hurricane-specific error covariance. On average, the analysis and forecast from the ETKF-EnVar have slightly smaller errors than that from the EDA-EnVar in terms of track, intensity, and precipitation forecast. Moreover, ETKF-EnVar yields better forecasts when verified against conventional observations.

  10. A novel B(var) allele (547 G>A) demonstrates differential expression depending on the co-inherited ABO allele.

    Science.gov (United States)

    Cho, D; Kim, S H; Ki, C S; Choi, K L; Cho, Y G; Song, J W; Shin, J H; Suh, S P; Yazer, M H; Ryang, D W

    2004-10-01

    Genetic analysis of group B donors in Korea was performed. Exons 6 and 7 were sequenced in 12 phenotypically B3 donors 6 B3, 6 A1B3. Consensus sequences all B3 and 2/6 A1B3 donors were present. Four A1B3 donors demonstrated a novel B allele, B(var), in the context of A101/ or A102/B(var) genotypes. Family studies based on an A1B3 donor with the B(var) allele and on another unrelated subject with identical genotype and phenotype revealed B(var)/O01 genotypes with full B-antigen expression. B(var) allele is subject to differential expression, depending on the co-inherited ABO allele.

  11. Analysis of 4D Var Data Assimilation Application Issues

    Science.gov (United States)

    Trailovic, L.; Etherton, B.; Harrop, C.; Govett, M.

    2016-12-01

    This paper summarizes the challenges encountered with our ongoing development and use of a software system designed to facilitate exploration of computational optimizations and strategies for Data Assimilation (DA). The software system is designed and constructed from scratch using modern software development methods and tools, though it incorporates components of pre-existing systems where appropriate. We present results of experiments that employ this system to test approaches for assimilation of observations using a four-dimensional variational (4D Var) scheme. We propose a modular DA system software architecture and demonstrate its utility using a set of models of varying realism and complexity. The software system design and implementation was initially tested and validated using a simple chaotic atmospheric model. A Quasi-Geostrophic (QG) atmospheric model was used to conduct DA experiments of increased difficulty and to validate the software design at larger scales of model complexity. Our QG DA study focused on 2016 winter weather data where a Nature run was used to represent the "true" state of the atmosphere and observations, whereas observation error covariance and observation operator were adapted from pre-existing DA systems. To increase performance, a parallel-in-time algorithm was applied to solve the proposed 4D Var data assimilation problem. That is, the assimilation window was divided into multiple sub-intervals, which allowed for parallelization of the cost function and gradient computations. Continuity equations of the solution were added as constraints across interval boundaries. This approach produced a different formulation of the variational data assimilation problem than weakly constrained 4D Var. We explored a combination of serial and parallel 4D Var algorithms to increase performance.

  12. The Influence of Sub-Unit Composition and Expression System on the Functional Antibody Response in the Development of a VAR2CSA Based Plasmodium falciparum Placental Malaria Vaccine

    DEFF Research Database (Denmark)

    Nielsen, Morten A; dos Santos Marques Resende, Mafalda; de Jongh, Willem A;

    2015-01-01

    of VAR2CSA, a parasite-derived antigen. Protection against PM is mediated by antibodies that inhibit binding of IE in the placental intervillous space. VAR2CSA is a large antigen incompatible with large scale recombinant protein expression. Vaccines based on sub-units encompassing the functionally......-functional antibodies, and furthermore influence the folding, stability and yield of expression. Candidate antigens from the pre-clinical development expressed in High-Five insect cells using the baculovirus expression vector system were transitioned into the Drosophila Schneider-2 cell (S2) expression-system compliant...... with clinical development. The functional capacity of antibodies against antigens expressed in High-Five cells or in S2 cells was equivalent. This enabled an extensive down-selection of S2 insect cell-expressed antigens primarily encompassing the minimal CSA-binding region of VAR2CSA. In general, we found...

  13. An analysis of the variation within Cratoxylum arborescens (Clusiaceae) in Malesia

    NARCIS (Netherlands)

    Church, A.C.; Stevens, P.F.

    1997-01-01

    The variation within the widespread West Malesian species Cratoxylum arborescens (Vahl) Blume was analyzed and three distinctive variants were found. These are recognized formally as varieties, var. arborescens, var. miquelii King, and var. borneense A.C. Church & P.F. Stevens. A key and full

  14. [Aspergillus galactomannan assay for the management of histoplasmosis due to Histoplasma capsulatum var. duboisii in HIV-infected patients: education from a clinical case].

    Science.gov (United States)

    Therby, A; Polotzanu, O; Khau, D; Monnier, S; Greder Belan, A; Eloy, O

    2014-06-01

    The diagnosis of histoplasmosis due to Histoplasma capsulatum var capsulatum is based on a direct examination identifying encapsulated yeast with narrow-based budding. Galactomannan antigenemia facilitates diagnosis, as well as the monitoring of patients receiving treatment. The case of a HIV-positive patient from Congo-Brazzaville with a disseminated form of African histoplasmosis highlighted the positive galactomannan antigen in this disease due to Histoplasma capsulatum var duboisii. Galactomannan antigenemia remained high with a very slow decrease during antifungal therapy and slow regression of clinical lesions. African histoplasmosis is a rare disease that is difficult to diagnose and rarely described in immunocompromised patients, in whom differential diagnosis can be common. This observation underlines the importance of the galactomannan antigen assay in patients who have travelled to endemic areas. As in the case of Histoplasma capsulatum var capsulatum, the positivity of the Aspergillus galactomannan antigen is very useful in the diagnosis and monitoring of African histoplasmosis.

  15. Var der noget kapløb?

    DEFF Research Database (Denmark)

    Gimpel, Denise; Nielsen, Bent

    2006-01-01

    . Som en af 1900-tallets største sinologer A. C. Graham skriver i sin bog Disputers of the Tao (La Salle, Ill., 1989) var den videnskabelige revolution »en unik og kompleks begivenhed, som var afhængig af en mangfoldighed af sociale og andre betingelser, herunder et sammenfald af opdagelser (græske...

  16. Arundina graminifolia var. revoluta (Arethuseae, Orchidaceae) has fern-type rheophyte characteristics in the leaves.

    Science.gov (United States)

    Yorifuji, Eri; Ishikawa, Naoko; Okada, Hiroshi; Tsukaya, Hirokazu

    2015-03-01

    Morphological and molecular variation between Arundina graminifolia var. graminifolia and the dwarf variety, A. graminifolia var. revoluta, was examined to assess the validity of their taxonomic characteristics and genetic background for identification. Morphological analysis in combination with field observations indicated that A. graminifolia var. revoluta is a rheophyte form of A. graminifolia characterized by narrow leaves, whereas the other morphological characteristics described for A. graminifolia var. revoluta, such as smaller flowers and short stems, were not always accompanied by the narrower leaf phenotype. Molecular analysis based on matK sequences indicated that only partial differentiation has occurred between A. graminifolia var. graminifolia and A. graminifolia var. revoluta. Therefore, we should consider the rheophyte form an ecotype rather than a variety. Anatomical observations of the leaves revealed that the rheophyte form of A. graminifolia possessed characteristics of the rheophytes of both ferns and angiosperms, such as narrower palisade tissue cells and thinner spongy tissue cells, as well as fewer cells in the leaf-width direction and fewer mesophyll cell layers.

  17. Toward variational assimilation of SARAL/Altika altimeter data in a North Atlantic circulation model at eddy-permitting resolution: assessment of a NEMO-based 4D-VAR system

    Science.gov (United States)

    Bouttier, Pierre-Antoine; Brankart, Jean-Michel; Candille, Guillem; Vidard, Arthur; Blayo, Eric; Verron, Jacques; Brasseur, Pierre

    2015-04-01

    In this project, the response of a variational data assimilation system based on NEMO and its linear tangent and adjoint model is investigated using a 4DVAR algorithm into a North-Atlantic model at eddy-permitting resolution. The assimilated data consist of Jason-2 and SARAL/AltiKA dataset collected during the 2013-2014 period. The main objective is to explore the robustness of the 4DVAR algorithm in the context of a realistic turbulent oceanic circulation at mid-latitude constrained by multi-satellite altimetry missions. This work relies on two previous studies. First, a study with similar objectives was performed based on academic double-gyre turbulent model and synthetic SARAL/AltiKA data, using the same DA experimental framework. Its main goal was to investigate the impact of turbulence on variational DA methods performance. The comparison with this previous work will bring to light the methodological and physical issues encountered by variational DA algorithms in a realistic context at similar, eddy-permitting spatial resolution. We also have demonstrated how a dataset mimicking future SWOT observations improves 4DVAR incremental performances at eddy-permitting resolution. Then, in the context of the OSTST and FP7 SANGOMA projects, an ensemble DA experiment based on the same model and observational datasets has been realized (see poster by Brasseur et al.). This work offers the opportunity to compare efficiency, pros and cons of both DA methods in the context of KA-band altimetric data, at spatial resolution commonly used today for research and operational applications. In this poster we will present the validation plan proposed to evaluate the skill of variational experiment vs. ensemble assimilation experiments covering the same period using independent observations (e.g. from Cryosat-2 mission).

  18. A Survey of ABO, Rhesus (D) Antigen and Haemoglobin Genes ...

    African Journals Online (AJOL)

    olayemitoyin

    This longitudinal study involved the determination of ABO and Rh(D) antigens in 3241 and ... Keywords: ABO antigen, Rhesus D, Blood group, Haemoglobin genotype, Blood substitutes ... composition, the variations in amino acid composition.

  19. arXiv Observation of the $\\varXi^{-}_{b}\\to J/\\psi\\varLambda K^{-}$ decay

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Babuschkin, Igor; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Balagura, Vladislav; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Baryshnikov, Fedor; Baszczyk, Mateusz; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betancourt, Christopher; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bitadze, Alexander; Bizzeti, Andrea; Blake, Thomas; Blanc, Frederic; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Bordyuzhin, Igor; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel Hugo; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cavallero, Giovanni; Cenci, Riccardo; Chamont, David; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chobanova, Veronika; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombs, George; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Costa Sobral, Cayo Mar; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Da Cunha Marinho, Franciole; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Demmer, Moritz; Dendek, Adam; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Déléage, Nicolas; Easo, Sajan; Ebert, Marcus; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Funk, Wolfgang; Furfaro, Emiliano; Färber, Christian; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gizdov, Konstantin; Gligorov, Vladimir; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gorelov, Igor Vladimirovich; Gotti, Claudio; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Griffith, Peter; Grillo, Lucia; Gruberg Cazon, Barak Raimond; Grünberg, Oliver; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Göbel, Carla; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hatch, Mark; He, Jibo; Head, Timothy; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hombach, Christoph; Hopchev, P H; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hutchcroft, David; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jiang, Feng; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Karacson, Matthias; Kariuki, James Mwangi; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Koliiev, Serhii; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kosmyntseva, Alena; Kozachuk, Anastasiia; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lanfranchi, Gaia; Langenbruch, Christoph; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Leflat, Alexander; Lefrançois, Jacques; Lefèvre, Regis; Lemaitre, Florian; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Tenglin; Li, Yiming; Likhomanenko, Tatiana; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Maltsev, Timofei; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marinangeli, Matthieu; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massacrier, Laure Marie; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurice, Emilie; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Mogini, Andrea; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Morgunova, Olga; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Mulder, Mick; Mussini, Manuel; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Thi Dung; Nguyen-Mau, Chung; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Nogay, Alla; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Oldeman, Rudolf; Onderwater, Gerco; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Pais, Preema Rennee; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Pastore, Alessandra; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pikies, Malgorzata; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Placinta, Vlad-Mihai; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Ratnikov, Fedor; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Remon Alepuz, Clara; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vicente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sadykhov, Elnur; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubert, Konstantin; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Soares Lavra, Lais; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavorima; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stevens, Holger; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Toriello, Francis; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Traill, Murdo; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tully, Alison; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Vernet, Maxime; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wang, Jianchun; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wraight, Kenneth; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yao, Yuezhe; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhang, Yu; Zhelezov, Alexey; Zheng, Yangheng; Zhu, Xianglei; Zhukov, Valery; Zucchelli, Stefano

    2017-01-01

    The observation of the decay $\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-}$ is reported, using a data sample corresponding to an integrated luminosity of $3~\\mathrm{fb}^{-1}$, collected by the LHCb detector in $pp$ collisions at centre-of-mass energies of $7$ and $8~\\mathrm{TeV}$. The production rate of $\\varXi_{b}^{-}$ baryons detected in the decay $\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-}$ is measured relative to that of $\\varLambda_{b}^{0}$ baryons using the decay $\\varLambda_{b}^{0}\\to J/\\psi \\varLambda$. Integrated over the $b$-baryon transverse momentum $p_{\\rm T}<25~\\mathrm{GeV/}c $ and rapidity $2.0 < y < 4.5$, the measured ratio is \\begin{equation*} \\frac{f_{\\varXi_{b}^{-}}}{f_{\\varLambda_{b}^{0}}}\\frac{\\mathcal{B}(\\varXi_{b}^{-}\\to J/\\psi\\varLambda K^{-})}{\\mathcal{B}(\\varLambda_{b}^{0}\\to J/\\psi \\varLambda)}=(4.19\\pm 0.29~(\\mathrm{stat})\\pm0.14~(\\mathrm{syst}))\\times 10^{-2}, \\end{equation*}where $f_{\\varXi_{b}^{-}}$ and $f_{\\varLambda_{b}^{0}}$ are the fragmentation fractions of $b\\to\\varXi_{...

  20. IgG responses to Anopheles gambiae salivary antigen gSG6 detect variation in exposure to malaria vectors and disease risk

    DEFF Research Database (Denmark)

    Stone, Will; Bousema, Teun; Jones, Sophie

    2012-01-01

    Assessment of exposure to malaria vectors is important to our understanding of spatial and temporal variations in disease transmission and facilitates the targeting and evaluation of control efforts. Recently, an immunogenic Anopheles gambiae salivary protein (gSG6) was identified and proposed as...

  1. Circular dichroism, molecular modeling, and serology indicate that the structural basis of antigenic variation in foot-and-mouth disease virus is [alpha]-helix formation

    Energy Technology Data Exchange (ETDEWEB)

    France, L.L.; Piatti, P.G.; Newman, J.F.E.; Brown, F. (Plum Island Animal Disease Center, Greenport, NY (United States)); Toth, I.; Gibbons, W.A. (Univ. of London (United Kingdom))

    1994-08-30

    Seven antigenic variants obtained from a single field isolate of foot-and-mouth disease virus, serotype A12, differ only at residues 148 and 153 in the immunodominant loop of viral protein VP1. Synthetic peptides corresponding to the region 141-160 are highly immunogenic. UV circular dichroism shows that (i) in aqueous solution of the peptides are nearly identical, but in 100% trifluoroethanol they display helix-forming properties which correlate well with their serological crossreactivities for anti-peptide sera, and (ii) these properties are insensitive to substitutions at position 153, except for proline, but are highly sensitive to substitutions at position 148. This pattern can be explained by the effects of these substitutions on the amphiphilic character and positions of helices postulated in the region 146-156. Molecular models indicate that residues 147, 148, 150, 151, 153-155, and 157 are most likely to interact with residues of the antibody paratopes. The data are consistent with the existence of an inverse [gamma]-turn around Pro-153, and a [beta]-turn at the cell-attachment site at residues 145-147. 31 refs., 5 figs.

  2. [Effects of mycorrhizal colonization and medicine quality of Paris polyphylla var. yunnanensis inoculated by different foreign AM fungi species].

    Science.gov (United States)

    Zhou Nong; Ding, Bo; Feng, Yuan; Qi, Wen-hua; Zhang, Hua; Guo, Dong-qin; Xiang, Jun

    2015-08-01

    After 28 foreign species of AM fungi were inoculated in sterilized soil, the effects of the AM mycorrhizal colonization and the medicine quality of Paris polyphylla var. yunnanensis were observed by combination of inoculation test in pot at room temperature and instrumental analysis. The results showed that, compared with control group (CK), the inoculation of foreign AM fungi in the soil influenced the spore density, mycorrhizal infection rate, and colonization intensity of AM fungi in root system of P. polyphylla var. yunnanensis. The inoculation of foreign AM fungi enhanced the mycorrhiza viability of P. polyphylla var. yunnanensis by increasing the activity of succinic dehydrogenase (SDH) and alkaline phosphatase (ALP) in intraradical hyphae. The content of single steroid saponin in rhizome of P. polyphylla var. yunnanensis showed variation after P. polyphylla var. yunnanensis was inoculated by different foreign species of AM fungi, which was beneficial for increasing the medicine quality; however, the kinds of steroid saponin showed no difference. In a degree, there was a selectivity of symbiosis between P. polyphylla var. yunnanensis and foreign AM fungi. And we found that the Claroideoglomus claroideum and Racocetra coralloidea were best foreign AM fungi species for cultivating P. polyphylla var. yunnanensis under field condition.

  3. FCH_Enveliopsis_nudicaulis_var_corrugata_19850520

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas where final critical habitat for the Ash Meadows sunray (Enceliopsis nudicaulis var. corrugata) occur.

  4. Variable cosmological term \\varLambda(t)

    Science.gov (United States)

    Socorro, J.; D'oleire, M.; Pimentel, Luis O.

    2015-11-01

    We present the case of time-varying cosmological term \\varLambda(t). The main idea arises by proposing that as in the cosmological constant case, the scalar potential is identified as V(φ)=2\\varLambda, with \\varLambda a constant, this identification should be kept even when the cosmological term has a temporal dependence, i.e., V(φ(t))=2\\varLambda(t). We use the Lagrangian formalism for a scalar field φ with standard kinetic energy and arbitrary potential V(φ) and apply this model to the Friedmann-Robertson-Walker (FRW) cosmology. Exact solutions of the field equations are obtained by a special ansatz to solve the Einstein-Klein-Gordon equation and a particular potential for the scalar field and barotropic perfect fluid. We present the evolution on this cosmological term with different scenarios.

  5. Rapid turnover of Plasmodium falciparum var gene transcripts and genotypes during natural non-symptomatic infections Rápida mudança de transcritos var e de génotipos de Plasmodium falciparum em infecções assintomáticas naturalmente adquiridas

    Directory of Open Access Journals (Sweden)

    Gerhard Wunderlich

    2005-08-01

    Full Text Available The var genes of Plasmodium falciparum code for the antigenically variant erythrocyte membrane proteins 1 (PfEMP1, a major factor for cytoadherence and immune escape of the parasite. Herein, we analyzed the var gene transcript turnover in two ongoing, non-symptomatic infections at sequential time points during two weeks. The number of different circulating genomes was estimated by microsatellite analyses. In both infections, we observed a rapid turnover of plasmodial genotypes and var transcripts. The rapidly changing repertoire of var transcripts could have been caused either by swift elimination of circulating var-transcribing parasites stemming from different or identical genetic backgrounds, or by accelerated switching of var gene transcription itself.Os genes var de Plasmodium falciparum codificam as proteínas variantes da superfície do eritrócito infectado (PfEMP1. Neste estudo examinamos a mudança de transcritos destes genes var em duas infecções assintomáticas durante um curto prazo e estimamos simultaneamente o número de genomas circulantes nas mesmas amostras por análise de microssatélites. Nas duas infecções observamos uma rápida mudança de genótipos e transcritos de genes var. A mudança acelerada do repertório de transcritos possivelmente foi causada pela rápida eliminação de parasitas circulantes transcrevendo genes var a partir de genomas iguais ou diferentes, ou pela mudança acelerada da própria transcrição (switching de genes var.

  6. Expression of Hepatitis B virus surface antigen (HBsAg from genotypes A, D and F and influence of amino acid variations related or not to genotypes on HBsAg detection

    Directory of Open Access Journals (Sweden)

    Natalia M. Araujo

    Full Text Available The impact of hepatitis B virus (HBV genotypes on the sensitivity of surface antigen (HBsAg detection assays has been poorly investigated. Here, plasmids carrying consensus or variant coding sequences for HBV surface proteins from genotypes A, D and F, were constructed. HBsAg levels were evaluated in medium and extracts of transfected CHO cells by a commercial polyclonal-based assay. We show that HBsAg detection values of consensus forms from genotypes D and F were, respectively, 37% and 30% lower than those obtained by genotype A. However, the presence of two single variations, T143M in genotype A, and T125M in genotype D, produced a decrease of 44% and an increase of 34%, respectively, on HBsAg mean values in comparison with their consensus forms. In conclusion, HBsAg detection levels varied among HBV genotypes. However, unique amino acid substitutions not linked to genotypes, such as T125M and T143M described here, should have more implications in HBV immunological diagnostics than the set of variations characteristic of each HBV genotype.

  7. Expression of Hepatitis B virus surface antigen (HBsAg from genotypes A, D and F and influence of amino acid variations related or not to genotypes on HBsAg detection

    Directory of Open Access Journals (Sweden)

    Natalia M. Araujo

    2009-08-01

    Full Text Available The impact of hepatitis B virus (HBV genotypes on the sensitivity of surface antigen (HBsAg detection assays has been poorly investigated. Here, plasmids carrying consensus or variant coding sequences for HBV surface proteins from genotypes A, D and F, were constructed. HBsAg levels were evaluated in medium and extracts of transfected CHO cells by a commercial polyclonal-based assay. We show that HBsAg detection values of consensus forms from genotypes D and F were, respectively, 37% and 30% lower than those obtained by genotype A. However, the presence of two single variations, T143M in genotype A, and T125M in genotype D, produced a decrease of 44% and an increase of 34%, respectively, on HBsAg mean values in comparison with their consensus forms. In conclusion, HBsAg detection levels varied among HBV genotypes. However, unique amino acid substitutions not linked to genotypes, such as T125M and T143M described here, should have more implications in HBV immunological diagnostics than the set of variations characteristic of each HBV genotype.

  8. Study on Variation of Drought-enduring Physiological Characteristics of Pinus sylvestis var. mongolica in Regions from Subhumid to Desert%樟子松耐旱的水分生理特征由亚湿润区至干旱区变化的研究

    Institute of Scientific and Technical Information of China (English)

    田有亮; 郭连生; 朱美云; 包永红

    2001-01-01

    The drought-enduring physiological characteristics of Pinus sylvestris var. mongolica measured and analyzed in the regions from subhumid to desert. The result showed that the bulk osmotic potential at initial turgor loss point (πp) and the bulk osmotic potential at water saturated state (π0), the main drought-enduring physiological indexes, have a significant regional difference (P0.05) and their variation in different regions correlated with the local climatic moisture index (Im), which can be expressed as y=A+Bx in early stage of young branch growth and y=Aexp(-B/x0.1) in last stage of yearly growth (y drought-enduring water physiological index; x climatic moistare index (Im): A, B regression coefficient).%在亚湿润区、半干旱区和干旱区设置样地,对樟子松人工林个体耐旱性水分生理指标测定结果进行统计分析表明,其主要耐旱生理指标初始失膨点渗透势和水饱和状态下的渗透势在地区间存在显著的差异(P<0.05);其变化与各地区气候湿度指标(Im)存在显著的相关性.在嫩枝生长初期可用y=A+Bx关系式表达,在生长季末期可用y=Aexp(-B/x0.1)表达,y为耐旱水分生理指标;x为气候湿度指标Im;A、B为系数.

  9. Genetic diversity of VAR2CSA ID1-DBL2Xb in worldwide Plasmodium falciparum populations: impact on vaccine design for placental malaria.

    Science.gov (United States)

    Bordbar, Bita; Tuikue Ndam, Nicaise; Renard, Emmanuelle; Jafari-Guemouri, Sayeh; Tavul, Livingstone; Jennison, Charlie; Gnidehou, Sédami; Tahar, Rachida; Gamboa, Dionicia; Bendezu, Jorge; Menard, Didier; Barry, Alyssa E; Deloron, Philippe; Sabbagh, Audrey

    2014-07-01

    In placental malaria (PM), sequestration of infected erythrocytes in the placenta is mediated by an interaction between VAR2CSA, a Plasmodium falciparum protein expressed on erythrocytes, and chondroitin sulfate A (CSA) on syncytiotrophoblasts. Recent works have identified ID1-DBL2Xb as the minimal CSA-binding region within VAR2CSA able to induce strong protective immunity, making it the leading candidate for the development of a vaccine against PM. Assessing the existence of population differences in the distribution of ID1-DBL2Xb polymorphisms is of paramount importance to determine whether geographic diversity must be considered when designing a candidate vaccine based on this fragment. In this study, we examined patterns of sequence variation of ID1-DBL2Xb in a large collection of P. falciparum field isolates (n=247) from different malaria-endemic areas, including Africa (Benin, Senegal, Cameroon and Madagascar), Asia (Cambodia), Oceania (Papua New Guinea), and Latin America (Peru). Detection of variants and estimation of their allele frequencies were performed using next-generation sequencing of DNA pools. A considerable amount of variation was detected along the whole gene segment, suggesting that several allelic variants may need to be included in a candidate vaccine to achieve broad population coverage. However, most sequence variants were common and extensively shared among worldwide parasite populations, demonstrating long term persistence of those polymorphisms, probably maintained through balancing selection. Therefore, a vaccine mixture including such stable antigen variants will be putatively applicable and efficacious in all world regions where malaria occurs. Despite similarity in ID1-DBL2Xb allele repertoire across geographic areas, several peaks of strong population differentiation were observed at specific polymorphic loci, pointing out putative targets of humoral immunity subject to positive immune selection.

  10. The taxonomic identity of Heliconius melpomene f. pyritosa var. fumigata Zikán (Lepidoptera: Nymphalidae

    Directory of Open Access Journals (Sweden)

    André Victor Lucci Freitas

    2015-06-01

    Full Text Available The taxonomic identity of the butterfly Heliconius melpomene f. pyritosa var. fumigata Zikán, 1937 (Nymphalidae: Heliconiinae is discussed based on the discovery of the specimen based on which this name was assigned. The specimen is not a variation of Eueides tales surdus Stichel, 1903, as previously stated, but is in fact a variation of H. melpomene f. pyritosa, which is a synonym of Heliconius erato amalfreda Riffarth, 1901.

  11. Production, Quality Control, Stability and Pharmacotoxicity of a Malaria Vaccine Comprising Three Highly Similar PfAMA1 Protein Molecules to Overcome Antigenic Variation

    Science.gov (United States)

    Houard, Sophie; Havelange, Nicolas; Drossard, Jürgen; Mertens, Hubert; Croon, Alexander; Kastilan, Robin; Byrne, Richard; van der Werff, Nicole; van der Eijk, Marjolein; Thomas, Alan W.; Kocken, Clemens H. M.; Remarque, Edmond J.

    2016-01-01

    Plasmodium falciparum apical membrane antigen 1 (PfAMA1) is a leading asexual blood stage vaccine candidate for malaria. In preparation for clinical trials, three Diversity Covering (DiCo) PfAMA1 ectodomain proteins, designed to overcome the intrinsic polymorphism that is present in PfAMA1, were produced under Good Manufacturing Practice (GMP) in Pichia pastoris. Using identical methodology, the 3 strains were cultivated in 70-L scale fed-batch fermentations and PfAMA1-DiCos were purified by two chromatography steps, an ultrafiltration/diafiltration procedure and size exclusion chromatography, resulting in highly pure (>95%) PfAMA1-DiCo1, PfAMA1 DiCo2 and PfAMA1 DiCo3, with final yields of 1.8, 1.9 and 1.3 gram, respectively. N-terminal determinations showed that approximately 50% of each of the proteins lost 12 residues from their N-terminus, in accordance with SDS-PAGE (2 main bands) and MS-data. Under reducing conditions a site of limited proteolytic cleavage within a disulphide bonded region became evident. The three proteins quantitatively bound to the mAb 4G2 that recognizes a conformational epitope, suggesting proper folding of the proteins. The lyophilized Drug Product (1:1:1 mixture of PfAMA1-DiCo1, DiCo2, DiCo3) fulfilled all pre-set release criteria (appearance, dissolution rate, identity, purity, protein content, moisture content, sub-visible particles, immuno-potency (after reconstitution with adjuvant), abnormal toxicity, sterility and endotoxin), was stable in accelerated and real-time stability studies at -20°C for over 24 months. When formulated with adjuvants selected for clinical phase I evaluation, the Drug Product did not show adverse effect in a repeated-dose toxicity study in rabbits. The Drug Product has entered a phase Ia/Ib clinical trial. PMID:27695087

  12. Allowing for model error in strong constraint 4D-Var

    Science.gov (United States)

    Howes, Katherine; Lawless, Amos; Fowler, Alison

    2016-04-01

    Four dimensional variational data assimilation (4D-Var) can be used to obtain the best estimate of the initial conditions of an environmental forecasting model, namely the analysis. In practice, when the forecasting model contains errors, the analysis from the 4D-Var algorithm will be degraded to allow for errors later in the forecast window. This work focusses on improving the analysis at the initial time by allowing for the fact that the model contains error, within the context of strong constraint 4D-Var. The 4D-Var method developed acknowledges the presence of random error in the model at each time step by replacing the observation error covariance matrix with an error covariance matrix that includes both observation error and model error statistics. It is shown that this new matrix represents the correct error statistics of the innovations in the presence of model error. A method for estimating this matrix using innovation statistics, without requiring prior knowledge of the model error statistics, is presented. The method is demonstrated numerically using a non-linear chaotic system with erroneous parameter values. We show that that the new method works to reduce the analysis error covariance when compared with a standard strong constraint 4D-Var scheme. We discuss the fact that an improved analysis will not necessarily provide a better forecast.

  13. Evidence for in vitro and in vivo expression of the conserved VAR3 (type 3) plasmodium falciparum erythrocyte membrane protein 1

    DEFF Research Database (Denmark)

    Wang, Christian W; Lavstsen, Thomas; Bengtsson, Dominique C

    2012-01-01

    ABSTRACT: BACKGROUND: Members of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) adhesion antigen family are major contributors to the pathogenesis of P. falciparum malaria infections. The PfEMP1-encoding var genes are among the most diverse sequences in nature, but three genes...

  14. [Hymenolepis nana var. fraterna (Cestoda: Hymenolepididae) in Leucophaea maderae (Dictyoptera: Blattidae): the host-parasite conflict after experimental inhibition of haemocytic reaction (author's transl)].

    Science.gov (United States)

    Pesson, B; Leger, N

    1978-01-01

    Development of non-encapsulated cysticercoids of Hymenolepis nana var. fraterna, in the haemocoele of Leucophaea maderae occured after the inhibition of the haemocytic reaction by irradiation or injection of a soluble antigen of Hymenolepis nana. Fine structure of the tegument of free larvae is observed and the mechanism of a possible defence of the parasite by the microvillar coat, discussed.

  15. The Influence of Sub-Unit Composition and Expression System on the Functional Antibody Response in the Development of a VAR2CSA Based Plasmodium falciparum Placental Malaria Vaccine.

    Directory of Open Access Journals (Sweden)

    Morten A Nielsen

    Full Text Available The disease caused by Plasmodium falciparum (Pf involves different clinical manifestations that, cumulatively, kill hundreds of thousands every year. Placental malaria (PM is one such manifestation in which Pf infected erythrocytes (IE bind to chondroitin sulphate A (CSA through expression of VAR2CSA, a parasite-derived antigen. Protection against PM is mediated by antibodies that inhibit binding of IE in the placental intervillous space. VAR2CSA is a large antigen incompatible with large scale recombinant protein expression. Vaccines based on sub-units encompassing the functionally constrained receptor-binding domains may, theoretically, circumvent polymorphisms, reduce the risk of escape-mutants and induce cross-reactive antibodies. However, the sub-unit composition and small differences in the borders, may lead to exposure of novel immuno-dominant antibody epitopes that lead to non-functional antibodies, and furthermore influence the folding, stability and yield of expression. Candidate antigens from the pre-clinical development expressed in High-Five insect cells using the baculovirus expression vector system were transitioned into the Drosophila Schneider-2 cell (S2 expression-system compliant with clinical development. The functional capacity of antibodies against antigens expressed in High-Five cells or in S2 cells was equivalent. This enabled an extensive down-selection of S2 insect cell-expressed antigens primarily encompassing the minimal CSA-binding region of VAR2CSA. In general, we found differential potency of inhibitory antibodies against antigens with the same borders but of different var2csa sequences. Likewise, we found that subtle size differences in antigens of the same sequence gave varying levels of inhibitory antibodies. The study shows that induction of a functional response against recombinant subunits of the VAR2CSA antigen is unpredictable, demonstrating the need for large-scale screening in order to identify antigens

  16. The Portfolio Decision Under the VaR Constraint

    Institute of Scientific and Technical Information of China (English)

    ChunfengWang; XinshuTu

    2004-01-01

    The VaR, a new appearing financial risk-manage tool, have been applied widely. Many financial setups have accustomed to measure the risk of a portfolio with the VaR. So it is very necessary to discuss the portfolio choice problem under the VaR constraint. In this paper, by setting and solving the portfolio choice model under the VaR constraint, we illustrate that the use of the VaR constraint reduces the array of choice to a more manageable range. The probability of traget VaR, therefore, can be thought of as a risk tolerance assessment tool (when coupled with another measure of risk).

  17. Hybrid VAR compensator with improved efficiency

    Directory of Open Access Journals (Sweden)

    V. V. Burlaka

    2015-03-01

    Full Text Available In modern electrical networks thyristor-switched capacitors (TSC are most used devices for VAR compensation. These devices don’t contain rotating parts and mechanical contacts, provide a stepwise control of reactive power and no generation of harmonics to the network. However, with the help of TSC it’s not possible to ensure smooth control of reactive power and capacitor banks (CB are exposed to the negative impact of higher harmonic components of the network voltage. Hybrid VAR compensator don’t have such drawbacks. It consists of active filter (AF and capacitor bank with discrete regulation. The main drawback of such systems is the necessity of accessing all six terminals of CB, while most of them are manufactured with three terminals, internally delta-connected. In the article, the topology and control system of hybrid VAR compensator free from beforementioned drawback, is proposed. The control system provides operating modes of overcompensation or undercompensation reactive power. VAR distribution regulator performs redistribution of reactive power between active filter and capacitor banks with the condition to minimize active filter’s power. Scheme of the hybrid VAR compensator, which includes a three-phase three-terminal delta-connected capacitor banks, is shown. Proposed approach allows to provide smooth control of reactive power, isolate the capacitor bank from harmonic currents and use a more effective low-voltage power components

  18. Putative DNA G-quadruplex formation within the promoters of Plasmodium falciparum var genes

    Directory of Open Access Journals (Sweden)

    Rowe J

    2009-08-01

    Full Text Available Abstract Background Guanine-rich nucleic acid sequences are capable of folding into an intramolecular four-stranded structure called a G-quadruplex. When found in gene promoter regions, G-quadruplexes can downregulate gene expression, possibly by blocking the transcriptional machinery. Here we have used a genome-wide bioinformatic approach to identify Putative G-Quadruplex Sequences (PQS in the Plasmodium falciparum genome, along with biophysical techniques to examine the physiological stability of P. falciparum PQS in vitro. Results We identified 63 PQS in the non-telomeric regions of the P. falciparum clone 3D7. Interestingly, 16 of these PQS occurred in the upstream region of a subset of the P. falciparum var genes (group B var genes. The var gene family encodes PfEMP1, the parasite's major variant antigen and adhesin expressed at the surface of infected erythrocytes, that plays a key role in malaria pathogenesis and immune evasion. The ability of the PQS found in the upstream regions of group B var genes (UpsB-Q to form stable G-quadruplex structures in vitro was confirmed using 1H NMR, circular dichroism, UV spectroscopy, and thermal denaturation experiments. Moreover, the synthetic compound BOQ1 that shows a higher affinity for DNA forming quadruplex rather than duplex structures was found to bind with high affinity to the UpsB-Q. Conclusion This is the first demonstration of non-telomeric PQS in the genome of P. falciparum that form stable G-quadruplexes under physiological conditions in vitro. These results allow the generation of a novel hypothesis that the G-quadruplex sequences in the upstream regions of var genes have the potential to play a role in the transcriptional control of this major virulence-associated multi-gene family.

  19. VaR BASED RISK MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Mária Bohdalová

    2013-06-01

    Full Text Available In this paper we discuss the Value–at–Risk concept and we analyse the market risk by using EWMA approach. EWMA (exponentially weighted moving average forecasting technique is a popular measure of various risks in financial risk management. We will compare standard EWMA, robust EWMA and skewed EWMA forecast of VaR. JP Morgan standard EWMA is derived from Gaussian distribution. Robust EWMA is based on Laplace distribution and skewed EWMA is a new approach derived from an asymmetric Laplace distribution. Asymmetric Laplace distribution takes into account both skewness and heavy tails in return distribution and the time varying nature of them in practice. Skewed EWMA VaR is a generalization of the standard EWMA method. Using these approaches we will analyse selected financial series (three European market indexes and one exchange rate. We have found andconfirmed that skewed EWMA forecasting of VaR outperforms the standard EWMA method.

  20. Haavelmo's Probability Approach and the Cointegrated VAR

    DEFF Research Database (Denmark)

    Juselius, Katarina

    Some key econometric concepts and problems addressed by Trygve Haavelmo and Ragnar Frisch are discussed within the general frame- work of a cointegrated VAR. The focus is on problems typical of time- series data such as multicollinearity, spurious correlation and regres- sion results, time......) the plausibility of the multivari- ate normality assumption underlying the VAR, (3) cointegration as a solution to the problem of spurious correlation and multicollinearity when data contain deterministic and stochastic trends, (4) the exis- tence of a universe, (5) the association between Frisch’s con...

  1. A comparison of yield-related traits of Coriandrum sativum var. microcarpum DC. and Coriandrum sativum var. sativum

    OpenAIRE

    Nikolay Dyulgerov; Boryana Dyulgerova

    2014-01-01

    In this investigation we studied how yield-related traits of large-fruited (var. sativum) and small-fruited (var. microcarpum DC.) coriander differ at the Southeastern Bulgaria climatic conditions during 2010-2012. For this purpose, 20 genotypes from var. microcarpum and 20 genotypes from var. sativum were tested using a randomized complete block design with three replications at the Institute of Agriculture – Karnobat. Plant height, number of primary branches per plant, number of umbels per ...

  2. A Structured VAR under Changing Monetary Policy

    DEFF Research Database (Denmark)

    Juselius, Katarina

    The empirical analysis is mainly concerned with the aggregate demand for money relation as part of a small macroeconomic system. Using the theory of cointegrated VAR models for I(2) data the long-run relationships in the data are first investigated, and the ML-estimates of the corresponding coint...

  3. Haavelmo's Probability Approach and the Cointegrated VAR

    DEFF Research Database (Denmark)

    Juselius, Katarina

    dependent residuals, normalization, reduced rank, model selection, missing variables, simultaneity, autonomy and iden- ti…cation. Speci…cally the paper discusses (1) the conditions under which the VAR model represents a full probability formulation of a sample of time-series observations, (2...

  4. Bacterial endosymbionts of Pyrodinium bahamense var. compressum.

    Science.gov (United States)

    Azanza, Ma Patricia V; Azanza, Rhodora V; Vargas, Vanessa Mercee D; Hedreyda, Cynthia T

    2006-11-01

    The study presents evidence in support of the bacterial theory associated with the toxicity of Pyrodinium bahamense var. compressum. Bacterial endosymbionts from Philippine P. bahamense var. compressum strain Pbc MZRVA 042595 were isolated and identified via 16S rDNA sequence analysis. Taxonomic diversity of the identified culturable intracellular microbiota associated with Philippine P. bahamense var. compressum was established to be limited to the Phyla Proteobacteria, Actinobacteria, and Firmicutes. Major endosymbionts identified included Moraxella spp., Erythrobacter spp., and Bacillus spp., whereas Pseudomonas putida, Micrococcus spp., and Dietzia maris were identified as minor isolates. All identified strains except D. maris, P. putida, and Micrococcus spp. were shown to contain either saxitoxin or neo saxitoxin or both at levels < or =73 ng/10(7) bacterial cells based on high-performance liquid chromatography analysis. Paralytic shellfish poisoning-like physiologic reactions in test animals used in the mouse assay were recorded for the endosymbionts except for P. putida. The study is the first to elucidate the possible contribution of bacterial endosymbionts in the toxicity of P. bahamense var. compressum isolated in the Philippines.

  5. Is Solanum ferox var. ferox (Solanaceae) extinct?

    NARCIS (Netherlands)

    Heiser, C.B.

    2001-01-01

    In 1995 I wrote letters to over 50 people (botanists, agricultural scientists, and former students of Indiana University) in south-eastern Asia trying to obtain a few seeds of Solanumferox L. var. ferox (S. involucratum Blume). I had over 25 replies, five of which included seeds, but none of the

  6. Is Solanum ferox var. ferox (Solanaceae) extinct?

    NARCIS (Netherlands)

    Heiser, C.B.

    2001-01-01

    In 1995 I wrote letters to over 50 people (botanists, agricultural scientists, and former students of Indiana University) in south-eastern Asia trying to obtain a few seeds of Solanumferox L. var. ferox (S. involucratum Blume). I had over 25 replies, five of which included seeds, but none of the see

  7. Selective upregulation of a single distinctly structured var gene in chondroitin sulphate A-adhering Plasmodium falciparum involved in pregnancy-associated malaria

    DEFF Research Database (Denmark)

    Salanti, Ali; Staalsoe, Trine; Lavstsen, Thomas

    2003-01-01

    Cytoadhesion of infected red blood cells (iRBC) is mediated through parasite-encoded, clonally variant surface antigens (VSA) and is a central process in the pathogenesis of Plasmodium falciparum malaria. Pregnancy-associated malaria (PAM) has been linked to VSA-mediated adhesion of i...... implicated in PfEMP1-mediated adhesion to CD36 and CSA. We also show that var2csa was transcribed at higher levels in three placental parasite isolates compared with transcription in parasites from peripheral blood of two children with P. falciparum malaria. This var gene thus has the properties expected...

  8. Variation in effects of non-Hodgkin lymphoma risk factors according to the human leukocyte antigen (HLA-DRB1*01:01 allele and ancestral haplotype 8.1.

    Directory of Open Access Journals (Sweden)

    Sophia S Wang

    Full Text Available Genetic variations in human leukocyte antigens (HLA are critical in host responses to infections, transplantation, and immunological diseases. We previously identified associations with non-Hodgkin lymphoma (NHL and the HLA-DRB1*01:01 allele and extended ancestral haplotype (AH 8.1 (HLA-A*01-B*08-DR*03-TNF-308A. To illuminate how HLA alleles and haplotypes may influence NHL etiology, we examined potential interactions between HLA-DRB1*01:01 and AH 8.1, and a wide range of NHL risk factors among 685 NHL cases and 646 controls from a United States population-based case-control study. We calculated odds ratios and 95% confidence intervals by HLA allele or haplotype status, adjusted for sex, age, race and study center for NHL and two major subtypes using polychotomous unconditional logistic regression models. The previously reported elevation in NHL risk associated with exposures to termite treatment and polychlorinated biphenyls were restricted to individuals who did not possess HLA-DRB1*01:01. Previous associations for NHL and DLBCL with decreased sun exposure, higher BMI, and autoimmune conditions were statistically significant only among those with AH 8.1, and null among those without AH 8.1. Our results suggest that NHL risk factors vary in their association based on HLA-DRB1*01:01 and AH 8.1 status. Our results further suggest that certain NHL risk factors may act through a common mechanism to alter NHL risk. Finally, control participants with either HLA-DRB1*01:01 or AH 8.1 reported having a family history of NHL twice as likely as those who did not have either allele or haplotype, providing the first empirical evidence that HLA associations may explain some of the well-established relationship between family history and NHL risk.

  9. Detoxification of Benzoxazolinone Allelochemicals from Wheat by Gaeumannomyces graminis var. tritici, G. graminis var. graminis, G. graminis var. avenae, and Fusarium culmorum

    OpenAIRE

    Friebe, A.; Vilich, V.; Hennig, L.; Kluge, M.; Sicker, D.

    1998-01-01

    The ability of phytopathogenic fungi to overcome the chemical defense barriers of their host plants is of great importance for fungal pathogenicity. We studied the role of cyclic hydroxamic acids and their related benzoxazolinones in plant interactions with pathogenic fungi. We identified species-dependent differences in the abilities of Gaeumannomyces graminis var. tritici, Gaeumannomyces graminis var. graminis, Gaeumannomyces graminis var. avenae, and Fusarium culmorum to detoxify these all...

  10. Potential of 4d-VAR for exigent forecasting of severe weather

    CERN Document Server

    Hoffman, Ross N; Nehrkorn, Thomas

    2011-01-01

    Severe storms, tropical cyclones, and associated tornadoes, floods, lightning, and microbursts threaten life and property. Reliable, precise, and accurate alerts of these phenomena can trigger defensive actions and preparations. However, these crucial weather phenomena are difficult to forecast. The objective of this paper is to demonstrate the potential of 4d-VAR (four dimensional variational data assimilation) for exigent forecasting (XF) of severe storm precursors and to thereby characterize the probability of a worst-case scenario. 4d-VAR is designed to adjust the initial conditions (IC) of a numerical weather prediction model consistent with the uncertainty of the prior estimate of the IC while at the same time minimizing the misfit to available observations. For XF the same approach is taken but instead of fitting observations, a measure of damage or loss or an equivalent proxy is maximized or minimized. To accomplish this will require development of a specialized cost function for 4d-VAR. When 4d-VAR s...

  11. Differential induction of functional IgG using the Plasmodium falciparum placental malaria vaccine candidate VAR2CSA.

    Directory of Open Access Journals (Sweden)

    Vera V Pinto

    Full Text Available BACKGROUND: In Plasmodium falciparum malaria endemic areas placental malaria (PM is an important complication of malaria. The recurrence of malaria in primigravidae women irrespective of acquired protection during childhood is caused by the interaction between the parasite-expressed VAR2CSA antigen and chondroitin sulfate A (CSA in the placental intervillous space and lack of protective antibodies. PM impairs fetal development mainly by excessive inflammation processes. After infections during pregnancy women acquire immunity to PM conferred by antibodies against VAR2CSA. Ideally, a vaccine against PM will induce antibody-mediated immune responses that block the adhesion of infected erythrocytes (IE in the placenta. PRINCIPAL FINDINGS: We have previously shown that antibodies raised in rat against individual domains of VAR2CSA can block IE binding to CSA. In this study we have immunized mice, rats and rabbits with each individual domain and the full-length protein corresponding to the FCR3 VAR2CSA variant. We found there is an inherently higher immunogenicity of C-terminal domains compared to N-terminally located domains. This was irrespective of whether antibodies were induced against single domains or the full-length protein. Species-specific antibody responses were also found, these were mainly directed against single domains and not the full-length VAR2CSA protein. CONCLUSIONS/SIGNIFICANCE: Binding inhibitory antibodies appeared to be against conformational B-cell epitopes. Non-binding inhibitory antibodies reacted highly against the C-terminal end of the VAR2CSA molecule especially the highly polymorphic DBL6ε domain. Differential species-specific induction of antibody responses may allow for more direct analysis of functional versus non-functional B-cell epitopes.

  12. Bolívar y Blanco White

    Directory of Open Access Journals (Sweden)

    Pons, André

    1998-12-01

    Full Text Available Not available.

    Este estudio procura poner de manifiesto la influencia de Blanco White, redactor de El Español (Londres, 1810-1814, en el ideario político de Bolívar, comparando el Manifiesto de Cartagena, la Carta de Jamaica y el Discurso de Angostura con los artículos de Blanco. Después de precisar las relaciones personales del periodista con el Libertador en Londres, se cotejan los textos y se muestra cómo Bolívar se inspiró en el periódico y lo utilizó en un doble sentido: subversivo, con objeto de justificar la lucha anticolonialista, y conservador, para analizar las dificultades de la independencia y de la democracia e imaginar el tipo de gobierno de los nacientes estados.

  13. Bioactive constituents of Cirsium japonicum var. australe.

    Science.gov (United States)

    Lai, Wan-Chun; Wu, Yang-Chang; Dankó, Balázs; Cheng, Yuan-Bin; Hsieh, Tusty-Jiuan; Hsieh, Chi-Ting; Tsai, Yu-Chi; El-Shazly, Mohamed; Martins, Ana; Hohmann, Judit; Hunyadi, Attila; Chang, Fang-Rong

    2014-07-25

    Cirsium japonicum var. australe, used as a folk medicine in Taiwan, has been employed traditionally in the treatment of diabetes and inflammatory symptoms. Bioactivity-guided fractionation of its ethanolic extract, utilizing centrifugal partition chromatography monitored by DPPH-TLC analysis, led to the isolation of three new acetylenic phenylacrylic acid esters (1-3) and two new polyacetylenes (4 and 5), together with seven known compounds (6-12). The structures of 1-5 were elucidated by spectroscopic methods including 1D and 2D NMR techniques. The absolute configurations of 4 and 7 were determined utilizing Mosher's method and ECD/CD experiments. The DPPH scavenging activity of the constituents isolated from the C. japonicum var. australe ethanolic extract was evaluated. The potential antidiabetic activity of some of the isolates was evaluated using in vitro cellular glucose uptake and oil red staining assays.

  14. Mutation studies in Cymbopogon nardus var. Confertiflorus

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, D.K.; Kak, S.N.; Kaul, B.L. (Regional Research Lab., Jammu (India))

    1981-09-01

    Vegetative slips of Cymbopogon nardus var, confertiflorus after irradiation with various doses of X-rays left a clone among the surviving plants that showed mutation resulting in a higher content of geranyl acetate. From its progeny, raised after selfing a fresh clone, possessing about 60% geranyl acetate in the oil without any effect on the herb yield, has been isolated. This mutant has a significant commercial importance as a new source of geranyl acetate, an important aroma chemical.

  15. An upstream open reading frame controls translation of var2csa, a gene implicated in placental malaria.

    Directory of Open Access Journals (Sweden)

    Borko Amulic

    2009-01-01

    Full Text Available Malaria, caused by the parasite Plasmodium falciparum, is responsible for substantial morbidity, mortality and economic losses in tropical regions of the world. Pregnant women are exceptionally vulnerable to severe consequences of the infection, due to the specific adhesion of parasite-infected erythrocytes in the placenta. This adhesion is mediated by a unique variant of PfEMP1, a parasite encoded, hyper-variable antigen placed on the surface of infected cells. This variant, called VAR2CSA, binds to chondroitin sulfate A on syncytiotrophoblasts in the intervillous space of placentas. VAR2CSA appears to only be expressed in the presence of a placenta, suggesting that its expression is actively repressed in men, children or non-pregnant women; however, the mechanism of repression is not understood. Using cultured parasite lines and reporter gene constructs, we show that the gene encoding VAR2CSA contains a small upstream open reading frame that acts to repress translation of the resulting mRNA, revealing a novel form of gene regulation in malaria parasites. The mechanism underlying this translational repression is reversible, allowing high levels of protein translation upon selection, thus potentially enabling parasites to upregulate expression of this variant antigen in the presence of the appropriate host tissue.

  16. Analysis list: Su(var)205 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Su(var)205 Adult,Embryo,Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3.../target/Su(var)205.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/Su(var)205.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/dm3/target/Su(var)205.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/c...olo/Su(var)205.Adult.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(v...ar)205.Embryo.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(var)205.Larvae.tsv http://dbarchive.bioscience

  17. Detoxification of Benzoxazolinone Allelochemicals from Wheat by Gaeumannomyces graminis var. tritici, G. graminis var. graminis, G. graminis var. avenae, and Fusarium culmorum.

    Science.gov (United States)

    Friebe; Vilich; Hennig; Kluge; Sicker

    1998-07-01

    The ability of phytopathogenic fungi to overcome the chemical defense barriers of their host plants is of great importance for fungal pathogenicity. We studied the role of cyclic hydroxamic acids and their related benzoxazolinones in plant interactions with pathogenic fungi. We identified species-dependent differences in the abilities of Gaeumannomyces graminis var. tritici, Gaeumannomyces graminis var. graminis, Gaeumannomyces graminis var. avenae, and Fusarium culmorum to detoxify these allelochemicals of gramineous plants. The G. graminis var. graminis isolate degraded benzoxazolin-2(3H)-one (BOA) and 6-methoxy-benzoxazolin-2(3H)-one (MBOA) more efficiently than did G. graminis var. tritici and G. graminis var. avenae. F. culmorum degraded BOA but not MBOA. N-(2-Hydroxyphenyl)-malonamic acid and N-(2-hydroxy-4-methoxyphenyl)-malonamic acid were the primary G. graminis var. graminis and G. graminis var. tritici metabolites of BOA and MBOA, respectively, as well as of the related cyclic hydroxamic acids. 2-Amino-3H-phenoxazin-3-one was identified as an additional G. graminis var. tritici metabolite of BOA. No metabolite accumulation was detected for G. graminis var. avenae and F. culmorum by high-pressure liquid chromatography. The mycelial growth of the pathogenic fungi was inhibited more by BOA and MBOA than by their related fungal metabolites. The tolerance of Gaeumannomyces spp. for benzoxazolinone compounds is correlated with their detoxification ability. The ability of Gaeumannomyces isolates to cause root rot symptoms in wheat (cultivars Rektor and Astron) parallels their potential to degrade wheat allelochemicals to nontoxic compounds.

  18. Transport of Bacillus thuringiensis var. Kurstaki Via Fomites

    Science.gov (United States)

    2011-01-01

    Special Feature: Remediation Transport of Bacillus Thuringiensis var. Kurstaki Via Fomites Sheila Van Cuyk, Lee Ann B. Veal, Beverley Simpson, and...evaluate biodefense concepts of operations using routine spraying of Bacillus thuringiensis var. kurstaki (Btk). Btk is dispersed in large quantities as...used is a water-based slurry containing Bacillus thuringiensis var. kurstaki (Btk). This bacterium produces a toxin that is lethal to gypsy moth

  19. Cell surface expression level variation between two common Human Leukocyte Antigen alleles, HLA-A2 and HLA-B8, is dependent on the structure of the C terminal part of the alpha 2 and the alpha 3 domains

    DEFF Research Database (Denmark)

    Dellgren, Christoffer; Nehlin, Jan O; Barington, Torben

    2015-01-01

    Constitutive cell surface expression of Human Leukocyte Antigen (HLA) class I antigens vary extremely from tissue to tissue and individual antigens may differ widely in expression levels. Down-regulation of class I expression is a known immune evasive mechanism used by cancer cells and viruses....... Moreover, recent observations suggest that even minor differences in expression levels may influence the course of viral infections and the frequency of complications to stem cell transplantation. We have shown that some human multipotent stem cells have high expression of HLA-A while HLA-B is only weakly...... expressed, and demonstrate here that this is also the case for the human embryonic kidney cell line HEK293T. Using quantitative flow cytometry and quantitative polymerase chain reaction we found expression levels of endogenous HLA-A3 (median 71,204 molecules per cell) 9.2-fold higher than the expression of...

  20. Antibodies to a full-length VAR2CSA immunogen are broadly strain-transcendent but do not cross-inhibit different placental-type parasite isolates.

    Directory of Open Access Journals (Sweden)

    Marion Avril

    Full Text Available The high molecular weight, multidomain VAR2CSA protein mediating adhesion of Plasmodium falciparum-infected erythrocytes in the placenta is the leading candidate for a pregnancy malaria vaccine. However, it has been difficult so far to generate strong and consistent adhesion blocking antibody responses against most single-domain VAR2CSA immunogens. Recent advances in expression of the full-length recombinant protein showed it binds with much greater specificity and affinity to chondroitin sulphate A (CSA than individual VAR2CSA domains. This raises the possibility that a specific CSA binding pocket(s is formed in the full length antigen and could be an important target for vaccine development. In this study, we compared the immunogenicity of a full-length VAR2CSA recombinant protein containing all six Duffy binding-like (DBL domains to that of a three-domain construct (DBL4-6 in mice and rabbits. Animals immunized with either immunogen acquired antibodies reacting with several VAR2CSA individual domains by ELISA, but antibody responses against the highly conserved DBL4 domain were weaker in animals immunized with full-length DBL1-6 recombinant protein compared to DBL4-6 recombinant protein. Both immunogens induced cross-reactive antibodies to several heterologous CSA-binding parasite lines expressing different VAR2CSA orthologues. However, antibodies that inhibited adhesion of parasites to CSA were only elicited in rabbits immunized with full-length immunogen and inhibition was restricted to the homologous CSA-binding parasite. These findings demonstrate that partial and full-length VAR2CSA immunogens induce cross-reactive antibodies, but inhibitory antibody responses to full-length immunogen were highly allele-specific and variable between animal species.

  1. Identification and in vivo functional analysis of a virginiamycin S resistance gene (varS) from Streptomyces virginiae.

    Science.gov (United States)

    Lee, C K; Kamitani, Y; Nihira, T; Yamada, Y

    1999-05-01

    BarA of Streptomyces virginiae is a specific receptor protein for virginiae butanolide (VB), one of the gamma-butyrolactone autoregulators of the Streptomyces species, and acts as a transcriptional regulator controlling both virginiamycin production and VB biosynthesis. The downstream gene barB, the transcription of which is under the tight control of the VB-BarA system, was found to be transcribed as a polycistronic mRNA with its downstream region, and DNA sequencing revealed a 1,554-bp open reading frame (ORF) beginning at 161 bp downstream of the barB termination codon. The ORF product showed high homology (68 to 73%) to drug efflux proteins having 14 transmembrane segments and was named varS (for S. virginiae antibiotic resistance). Heterologous expression of varS with S. lividans as a host resulted in virginiamycin S-specific resistance, suggesting that varS encoded a virginiamycin S-specific transport protein. Northern blot analysis indicated that the bicistronic transcript of barB-varS appeared 1 to 2 h before the onset of virginiamycin M1 and S production, at which time VB was produced, while exogenously added virginiamycin S apparently induced the monocistronic varS transcript.

  2. A 4D-Ensemble-Variational System for Data Assimilation and Ensemble Initialization

    Science.gov (United States)

    Bowler, Neill; Clayton, Adam; Jardak, Mohamed; Lee, Eunjoo; Jermey, Peter; Lorenc, Andrew; Piccolo, Chiara; Pring, Stephen; Wlasak, Marek; Barker, Dale; Inverarity, Gordon; Swinbank, Richard

    2016-04-01

    The Met Office has been developing a four-dimensional ensemble variational (4DEnVar) data assimilation system over the past four years. The 4DEnVar system is intended both as data assimilation system in its own right and also an improved means of initializing the Met Office Global and Regional Ensemble Prediction System (MOGREPS). The global MOGREPS ensemble has been initialized by running an ensemble of 4DEnVars (En-4DEnVar). The scalability and maintainability of ensemble data assimilation methods make them increasingly attractive, and 4DEnVar may be adopted in the context of the Met Office's LFRic project to redevelop the technical infrastructure to enable its Unified Model (MetUM) to be run efficiently on massively parallel supercomputers. This presentation will report on the results of the 4DEnVar development project, including experiments that have been run using ensemble sizes of up to 200 members.

  3. Lignans from Schisandra propinqua var. propinqua.

    Science.gov (United States)

    Lei, Chun; Huang, Sheng-Xiong; Chen, Ji-Jun; Pu, Jian-Xin; Yang, Li-Bin; Zhao, Yong; Liu, Jin-Ping; Gao, Xue-Mei; Xiao, Wei-Lie; Sun, Han-Dong

    2007-08-01

    Two new dibenzocyclooctadiene lignans angeloyl-(+)-gomisin K(3) (1) and methylisogomisin O (2), together with six known ones, isogomisin O, angeloylisogomisin O, gomisin O, angeloygomisin O, benzoylgomisin O, epigomisin O, and four 1,4-bis(phenyl)-2,3-dimethylbutane type lignans, pregomisin, meso-dihydroguaiaretic acid, isoanwulignan, and sphenanlignan were isolated from the aerial parts of Schisandra propinqua var. propinqua. The structures of 1 and 2 were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques.

  4. A universal computational model for predicting antigenic variants of influenza A virus based on conserved antigenic structures

    Science.gov (United States)

    Peng, Yousong; Wang, Dayan; Wang, Jianhong; Li, Kenli; Tan, Zhongyang; Shu, Yuelong; Jiang, Taijiao

    2017-01-01

    Rapid determination of the antigenicity of influenza A virus could help identify the antigenic variants in time. Currently, there is a lack of computational models for predicting antigenic variants of some common hemagglutinin (HA) subtypes of influenza A viruses. By means of sequence analysis, we demonstrate here that multiple HA subtypes of influenza A virus undergo similar mutation patterns of HA1 protein (the immunogenic part of HA). Further analysis on the antigenic variation of influenza A virus H1N1, H3N2 and H5N1 showed that the amino acid residues’ contribution to antigenic variation highly differed in these subtypes, while the regional bands, defined based on their distance to the top of HA1, played conserved roles in antigenic variation of these subtypes. Moreover, the computational models for predicting antigenic variants based on regional bands performed much better in the testing HA subtype than those did based on amino acid residues. Therefore, a universal computational model, named PREDAV-FluA, was built based on the regional bands to predict the antigenic variants for all HA subtypes of influenza A viruses. The model achieved an accuracy of 0.77 when tested with avian influenza H9N2 viruses. It may help for rapid identification of antigenic variants in influenza surveillance. PMID:28165025

  5. Validation of the name Callicarpa bodinieri var.iteophylla (Lamiaceae)

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ming PENG; Nan JIANG; Wen-Bin YU

    2011-01-01

    Callicarpa bodinieri H.Léveillé var.iteophylla C.Y.Wu,var.nov.Type:China.Yunnan:Mengla,1953-06-03,Yong-Shu Wang 27 (holotype,KUN 0484466!;isotype,KUN 0484467!).Validating diagnosis:Those ofCallicarpa bodinieri H.Léveillé var.iteophylla C.Y.Wu,Fl.Yunnan.1:406.1977.Callicarpa bodinieri H.Léveillé var.iteophylla C.Y.Wu is endemic to southern Yunnan province of China,and it occurs in mixed forests at altitudes between 600 and 1600 m.This new variety is easily distinguished from var.bodinieri and var.rosthornii (Diels)Rehder in that the leaf blade is lanceolate,oblanceolate,or obovateoblong,and 2-4 cm wide (vs.narrowly elliptic,elliptic,or ovateelliptic,and 4-7 cm wide in var.bodinieri),and subglabrous on both surfaces (vs.abaxially grayish stellate pubescent in var.rosthornii).

  6. VaR Methodology Application for Banking Currency Portfolios

    Directory of Open Access Journals (Sweden)

    Daniel Armeanu

    2007-02-01

    Full Text Available VaR has become the standard measure that financial analysts use to quantify market risk. VaR measures can have many applications, such as in risk management, to evaluate the performance of risk takers and for regulatory requirements, and hence it is very important to develop methodologies that provide accurate estimates. In particular, the Basel Committee on Banking Supervision at the Bank for International Settlements imposes to financial institutions such as banks and investment firms to meet capital requirements based on VaR estimates. In this paper we determine VaR for a banking currency portfolio and respect rules of National Bank of Romania regarding VaR report.

  7. An upstream open reading frame controls translation of var2csa, a gene implicated in placental malaria

    DEFF Research Database (Denmark)

    Amulic, Borko; Salanti, Ali; Lavstsen, Thomas

    2009-01-01

    to only be expressed in the presence of a placenta, suggesting that its expression is actively repressed in men, children or non-pregnant women; however, the mechanism of repression is not understood. Using cultured parasite lines and reporter gene constructs, we show that the gene encoding VAR2CSA...... contains a small upstream open reading frame that acts to repress translation of the resulting mRNA, revealing a novel form of gene regulation in malaria parasites. The mechanism underlying this translational repression is reversible, allowing high levels of protein translation upon selection, thus...... potentially enabling parasites to upregulate expression of this variant antigen in the presence of the appropriate host tissue....

  8. A molecular marker for in situ genetic resource conservation of Capsicum annuum var. acuminatum (Solanaceae).

    Science.gov (United States)

    Kaewdoungdee, N; Tanee, T

    2013-02-28

    The Thailand cultivar pepper 'phrik man bangchang' (Capsicum annuum var. acuminatum, Solanaceae) was originally cultivated in the Bangchang Subdistrict, Amphawa District in Samut Songkhram Province. The cultivated areas are limited; we verified its distribution in Thailand for in situ 'phrik man bangchang' genetic resource conservation. Samples were collected from the original cultivation area of Bangchang Subdistrict (Or) and were randomly explored in Ratchaburi Province (RB), Khon Kaen Province (KK), and Sakon Nakhon Province (SN). A pure line from The Tropical Vegetable Research Center at Kasetsart University was used as the standard indicator. Two more Capsicum species, C. chinensis and C. frutescens, and a species from another genus in the family, Solanum melongena, were included. A dendrogram constructed from random amplified polymorphic DNA fingerprints indicated that the Or, RB, KK, and SN samples were C. annuum var. acuminatum with supportive similarity coefficients of 0.79 to 0.98. Finally, DNA barcodes, from psbA-trnH spacer region, were provided for the 3 wild species, C. annuum var. acuminatum, C. chinensis, and C. frutescens under GenBank accession Nos. JQ087869-JQ087871. The nucleotide variations between species were 0.23 to 0.26. In summary, 'phrik man bangchang' is still being planted in Bangchang Subdistrict, but only in small areas. The distribution of planting areas is expected to be throughout Thailand.

  9. Data assimilation (4D-VAR) to forecast flood in shallow-waters with sediment erosion

    Science.gov (United States)

    Bélanger, Eric; Vincent, Alain

    2005-01-01

    In this paper, the four-dimensional variational data assimilation technique (4D-VAR) is presented as a tool to forecast floods. Our study is limited to purely hydrological flows and supposes that the weather, here a big rain, has been already forecasted by meteorological services. The technique consists in minimizing, in the sense of Lagrange, the cost function: a measure of the difference between calculated data and available observations, here the water level. This is done under constraints that are the equations of the physical model. In our case, we modified the shallow-water equations to include a simplified sediment transport model. The steepest descent algorithm is then used to find the minimum. This is made possible because we can compute analytically the gradient of the cost function by using the adjoint equations of the model. As an application of the 4D-VAR technique, the overflowing of the Chicoutimi River at the Chute-Garneau dam, during the 1996 flood, is investigated. It is found that the 4D-VAR method reduces the error in the water height forecast even when the erosion model is not activated. In terms of Lyapunov exponents, we estimate the predictability horizon of such an event to be about half-an-hour after a big rain. However, this limit of predictability can be increased by using more observations or by using a finer computational grid.

  10. Eosinofil Sel Penyaji Antigen

    Directory of Open Access Journals (Sweden)

    Safari Wahyu Jatmiko

    2015-04-01

    Full Text Available Sel eosinofil merupakan jenis sel lekosit yang terlibat dalam berbagai patogenesis penyakit. Sel eosinofil pada awalnya dikenal sebagai sel efektor  dari sistem imunitas alamiah. Akan tetapi, kemampuan sel eosinofil dalam memfagositosis patogen menimbulkan dugaan bahwa sel eosinofil ikut berperan sebagai sel penyaji antigen. Hal ini dianalogikan dengan sel makrofag dan sel dendritik yang bisa memfagositosis dan menyajikan antigen sebagai hasil dari degradasi patogen yang difagositosis. Untuk menjawab permasalahan ini, penulis melakukan penelusuran artikel tentang eosinofil sebagai sel penyaji antigen melalui US National Library of Medicine National Institute of Healthdengan kata kunci eoshinophil dan antigen presenting cell. Hasil penelusuran adalah ditemukannya 10 artikel yang relevan dengan topik. Hasil dari sintesis kesepuluh jurnal tersebut adalah sel eosinofil mampu berperan sebagai sel penyaji antigen yang profesional (professionalantigenpresentng cell

  11. Chemical diversity of volatiles of Teucrium orientale L. var. orientale, var. puberulens, and var. glabrescens determined by simultaneous GC-FID and GC/MS techniques.

    Science.gov (United States)

    Ozek, Gulmira; Ozek, Temel; Dinç, Muhittin; Doǧu, Süleyman; Başer, Kemal H C

    2012-06-01

    In the present work, three varieties of Teucrium orientale, var. orientale, var. puberulens, and var. glabrescens, were collected and investigated for chemical composition of the oils. Subsequent gas chromatography (GC-FID) and gas chromatography coupled to mass spectrometry (GC/MS) revealed high abundance of sesquiterpenes in the essential oils analyzed. All the oils contained β-caryophyllene (22.6, 8.5, and 6.3%, resp.) and hexadecanoic acid (7.9, 12.8, and 13.1%). Germacrene D (24.6 and 33.4%) and bicyclogermacrene (6.7 and 8.5%) were found to be the main constituents of var. orientale and var. puberulens, respectively. The high percentages of β-cubebene (26.9%), α-cubebene (9.0%), and α-copaene (7.2%) established the diversity of var. glabrescens. The qualitative difference between the essential oils allowed the differentiation between the varieties in agreement with the morphological observations described in Flora of Turkey for each variety studied. In addition, a cluster analysis of twelve Teucrium taxa based on the essential-oil composition has been carried out. Hovewer, the analysis did not clearly reflect the infrageneric classification of the genus, it largely confirmed the relationships between the infraspecific taxa of Teucrium orientale and T. chamaedrys.

  12. 1D-Var temperature retrievals from microwave radiometer and convective scale model

    Directory of Open Access Journals (Sweden)

    Pauline Martinet

    2015-12-01

    Full Text Available This paper studies the potential of ground-based microwave radiometers (MWR for providing accurate temperature retrievals by combining convective scale numerical models and brightness temperatures (BTs. A one-dimensional variational (1D-Var retrieval technique has been tested to optimally combine MWR and 3-h forecasts from the French convective scale model AROME. A microwave profiler HATPRO (Humidity and Temperature PROfiler was operated during 6 months at the meteorological station of Bordeaux (Météo France. MWR BTs were monitored against simulations from the Atmospheric Radiative Transfer Simulator 2 radiative transfer model. An overall good agreement was found between observations and simulations for opaque V-band channels but large errors were observed for channels the most affected by liquid water and water vapour emissions (51.26 and 52.28 GHz. 1D-Var temperature retrievals are performed in clear-sky and cloudy conditions using a screening procedure based on cloud base height retrieval from ceilometer observations, infrared radiometer temperature and liquid water path derived from the MWR observations. The 1D-Var retrievals were found to improve the AROME forecasts up to 2 km with a maximum gain of approximately 50 % in root-mean-square-errors (RMSE below 500 m. They were also found to outperform neural network retrievals. A static bias correction was proposed to account for systematic instrumental errors. This correction was found to have a negligible impact on the 1D-Var retrievals. The use of low elevation angles improves the retrievals up to 12 % in RMSE in cloudy-sky in the first layers. The present implementation achieved a RMSE with respect to radiosondes within 1 K in clear-sky and 1.3 K in cloudy-sky conditions for temperature.

  13. Periodicity of Wuchereria bancrofti var. pacifica filariasis in French Polynesia.

    Science.gov (United States)

    Moulia-Pelat, J P; Glaziou, P; Chanteau, S; Nguyen-Ngoc, L; Marcet, Y; Gardines, R; Martin, P M; Cartel, J L

    1993-06-01

    In 1992, a study on microfilaremia periodicity was carried out on 12 Wuchereria bancrofti carriers in the Marquesas islands. Blood samples were collected simultaneously every 4 hours during a 48 hour period by finger-prick and venipuncture for determination of microfilaremia by both blood film and membrane filtration technique methods, and for determination of antigenemia. The membrane filtration results showed no significant nycthemeral variations between the microfilaria densities at hours 16:00, 20:00, 24:00, 04:00, 08:00 and 12:00. Conversely, the blood film method showed a significant difference between the microfilaria densities: the microfilaremia was higher during the day (12:00-20:00 hours) than during the night (24:00-08:00 hours). As for antigenemia, using Og 4 C3 monoclonal antibody, there was no significant fluctuation during 48 hours. These results confirm that W. bancrofti var. pacifica is subperiodic and diurnal in French Polynesia. In particular, they substantiate the validity of examining venous blood by the membrane filtration technique as the judgment criterion of choice in therapeutic trials and of examining capillary blood during peak hours by the blood film method for evaluating the endemic level in a population.

  14. Lack of gender-specific antibody recognition of products from domains of a var gene implicated in pregnancy-associated Plasmodium falciparum malaria

    DEFF Research Database (Denmark)

    Jensen, Anja T R; Zornig, Hanne D; Buhmann, Caecilie

    2003-01-01

    Gender-specific and parity-dependent acquired antibody recognition is characteristic of variant surface antigens (VSA) expressed by chondroitin sulfate A (CSA)-adherent Plasmodium falciparum involved in pregnancy-associated malaria (PAM). However, antibody recognition of recombinant products...... of a specific VSA gene (2O2var1) implicated in PAM and transcribed by a CSA-adhering parasite line did not have these characteristics. Furthermore, we could not demonstrate preferential transcription of 2O2var1 in the CSA-adhering line versus the unselected, parental isolate. Our data call for circumspection...... regarding the molecular identity of the parasite ligand mediating adhesion to CSA in PAM....

  15. Microsatellite typing of clinical and environmental Cryptococcus neoformans var. grubii isolates from Cuba shows multiple genetic lineages.

    Directory of Open Access Journals (Sweden)

    Maria-Teresa Illnait-Zaragozi

    Full Text Available BACKGROUND: Human cryptococcal infections have been associated with bird droppings as a likely source of infection. Studies toward the local and global epidemiology of Cryptococcus spp. have been hampered by the lack of rapid, discriminatory, and exchangeable molecular typing methods. METHODOLOGY/PRINCIPAL FINDINGS: We selected nine microsatellite markers for high-resolution fingerprinting from the genome of C. neoformans var. grubii. This panel of markers was applied to a collection of clinical (n = 122 and environmental (n = 68; from pigeon guano C. neoformans var. grubii isolates from Cuba. All markers proved to be polymorphic. The average number of alleles per marker was 9 (range 5-51. A total of 104 genotypes could be distinguished. The discriminatory power of this panel of markers was 0.993. Multiple clusters of related genotypes could be discriminated that differed in only one or two microsatellite markers. These clusters were assigned as microsatellite complexes. The majority of environmental isolates (>70% fell into 1 microsatellite complex containing only few clinical isolates (49 environmental versus 2 clinical. Clinical isolates were segregated over multiple microsatellite complexes. CONCLUSIONS/SIGNIFICANCE: A large genotypic variation exists in C. neoformans var. grubii. The genotypic segregation between clinical and environmental isolates from pigeon guano suggests additional source(s of human cryptococcal infections. The selected panel of microsatellite markers is an excellent tool to study the epidemiology of C. neoformans var. grubii.

  16. Some tests for parameter constancy in cointegrated VAR-models

    DEFF Research Database (Denmark)

    Hansen, Henrik; Johansen, Søren

    1999-01-01

    Some methods for the evaluation of parameter constancy in vector autoregressive (VAR) models are discussed. Two different ways of re-estimating the VAR model are proposed; one in which all parameters are estimated recursively based upon the likelihood function for the first observations, and anot...... be applied to test the constancy of the long-run parameters in the cointegrated VAR-model. All results are illustrated using a model for the term structure of interest rates on US Treasury securities. ...

  17. CEA (Carcinoembryonic Antigen) Test

    Science.gov (United States)

    ... as: CEA Formal name: Carcinoembryonic Antigen Related tests: Tumor Markers , CSF Analysis , Body Fluid Analysis , CA 19-9 , Calcitonin , AFP Tumor Markers All content on Lab Tests Online has been ...

  18. 不同盐梯度处理下沼泽小叶桦的生理特征及叶片结构%Photosynthetic Performance and Variation in Leaf Anatomic Structure of Betula microphylla var.paludosa under Different Saline Conditions

    Institute of Scientific and Technical Information of China (English)

    王斌; 巨波; 赵慧娟; 张群; 朱义; 崔心红

    2011-01-01

    设计盐梯度(0,2‰,4‰,6‰,8‰盐溶液的质量比为NaCl∶ Na2SO4∶ NaHCO3=75%∶15%∶10%)试验分析沼泽小叶桦生理表现和叶片解剖结构.结果显示:在低于4‰盐度时沼泽小叶桦能正常生长,6%‰盐度时沼泽小叶桦生长发育不良,当盐度8‰时沼泽小叶桦只能存活30天左右;在低盐度处理下沼泽小叶桦光合生理表现和叶片解剖结构正常;随着盐度增加,其叶片净光合速率、气孔导度、胞间CO2浓度、蒸腾速率、叶绿素含量等指标均下降,而叶片中可溶性糖含量、脯氨酸含量、蛋白质含量升高;当盐度≥0.4%时,沼泽小叶桦叶片栅栏细胞逐渐纵向伸长且排列更紧密,叶绿体从椭圆形变成球形,叶绿体中出现粗大的淀粉粒和脂质球,表明其对滨海盐土具有一定的适应能力.%Betula microphylla var. Paludosa is a salt tolerant plant and naturally grows in inland. In order to explore possibility in transplanting the species to marine salina, we investigated photosynthetic performance and leaf anatomic structure of B. Microphylla , grown under control (nutrient soil) or salt-stress conditions (nutrient soil containing different salinity; 2‰, 4‰, 6‰, 8‰ of the solution for 60 days. The species had normal photosynthetic performance and leaf anatomic structure under lower salinity conditions. When soil salinity increased (≥0. 4%) , the net photosynthesis rate, stomatal conductance, transpiration rate, internal CO2 concentration, and chlorophyll content in leaves all decreased, whereas the soluble sugar, proline and protein contents of leaf increased. Accordingly, cells of the palisade tissue in B. Microphylla var. Paludosa leaf elongated and piled closely, in comparison with that under lower salinity conditions, and the chloroplasts changed from elliptical shape to round shape and in which many 1 ipid droplets and starch grains occurred in it. These results indicated that B. Microphylla var

  19. Variação na resistência à ferrugem e na composição do óleo essencial de dois clones de menta Variation on the rust resistance and essential oil composition of two clones of Mentha arvensis L Var piperascens Malinvaud

    Directory of Open Access Journals (Sweden)

    Mario Guilherme Roberto Donalísio

    1985-01-01

    Full Text Available Foram estudadas no Centro Experimental de Campinas, entre 1973 e 1976, 450 progênies do clone Samby e 295 do clone Valinhos, ambos da espécie Mentha arvensis L. var. piperascens Malinvaud, que apresentavam alguma resistência à ferrugem causada pelo fungo Puccinia menthae Pers., bom desenvolvimento vegetativo e óleo essencial com alto teor em mentol. As progênies foram obtidas de polinização livre. As plantas que apresentavam pulegona foram eliminadas por seleção olfativa, e as restantes, inoculadas com uredosporos de P. menthae Pers. e, posteriormente, classificadas em três notas de resistência à doença. Em pleno florescimento, as plantas foram destiladas em corrente de vapor, e o óleo essencial obtido analisado em cromatógrafo de gás para avaliação quantitativa de seus componentes principais: mentol, mentona e pulegona. Destacaram-se oito progênies do clone Valinhos e catorze do Samby, respectivamente, mentol entre 75,85-85,18% e 77,12-83,74%, e pulegona entre 0,48-1,36% e 0,94-2,05% pela resistência à ferrugem. Três progênies do clone Valinhos e duas do Samby apresentaram baixos teores do mentol: 56,65, 56,94 e 60,11, e 54,26 e 64,93% respectivamente, semelhantes aos verificados nos óleos desmentolados de M. arvensis L.Seedlings froco two clones of M. arvensis L var. piperascens Malinvaud were selected by olfative test to eliminate the plants with high pulegone content in the essencial oil; the selected plants were inoculated with spore suspension of Puccinia menthae Pers., and classified in three classes of susceptibility. The blooming plants were distilled and the obtained samples of essential oil were analysed by gas chromatography to verify its menthol, menthone and pulegone contents. The data showed that the studied material presents high variability to rust resistance and menthol content in its essencial oil. Eight progenies from Valinhos clone presented high rust resistance, 75.80% to 85.18% menthol and 0.48 to

  20. Effects of Bacillus cereus var. toyoi on immune parameters of pregnant sows.

    Science.gov (United States)

    Schierack, Peter; Filter, Matthias; Scharek, Lydia; Toelke, Christiane; Taras, David; Tedin, Karsten; Haverson, Karin; Lübke-Becker, Antina; Wieler, Lothar H

    2009-01-15

    Changing immune parameters during pregnancy have previously been reported in humans and cattle, and have been suggested to contribute to increased susceptibility to infections. However, data regarding immune parameters during pregnancy in sows are rare. In this study, we investigated the peripartal immune status of sows using phenotypical (FACS analysis) as well as functional (proliferation assays, cytokine analysis) parameters of peripheral blood mononuclear cells (PBMCs) in pregnant sows. In previous studies, we reported a modulation of the immune system after feed supplementation of the probiotic Bacillus cereus var. toyoi in piglets [Schierack, P., Wieler, L.H., Taras, D., Herwig, V., Tachu, B., Hlinak, A., Schmidt, M.F., Scharek, L., 2007. Bacillus cereus var. toyoi enhanced systemic immune response in piglets. Vet. Immunol. Immunopathol. 118, 1-11]. Here, we extended these previous studies to include investigations of possible probiotic effects on the peripartal immune status of sows and their reproductivity. We show that immune parameters of sows change during pregnancy, the proliferative response of PBMCs to several bacterial antigens in control animals decreased from days 90 to 30 ante partum. Relative numbers (%) of CD3+CD8+, CD4+, cytotoxic T, CD14+ and CD21+ cells were reduced compared to non-pregnant sows. In contrast, the proliferative response of PBMCs of probiotic-treated sows increased during pregnancy. Bacterial antigens primarily stimulated the proliferation of naïve CD21+ cells and the relative CD21+ cell numbers were elevated in the probiotic group in the absence of effects on other immune cell populations. The clinical and microbial status of both control and probiotic sows was similar, excluding pre-existing health problems or infections as responsible for the immunological changes, and feed supplementation also had no significant effects on reproductivity. The results suggest that the probiotic B. cereus var. toyoi can alter the

  1. Pitfalls in VAR based return decompositions: A clarification

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard; Tanggaard, Carsten

    Based on Chen and Zhao's (2009) criticism of VAR based return de- compositions, we explain in detail the various limitations and pitfalls involved in such decompositions. First, we show that Chen and Zhao's interpretation of their excess bond return decomposition is wrong: the residual component...... in their analysis is not "cashflow news" but "inter- est rate news" which should not be zero. Consequently, in contrast to what Chen and Zhao claim, their decomposition does not serve as a valid caution against VAR based decompositions. Second, we point out that in order for VAR based decompositions to be valid....... In a properly specified VAR, it makes no difference whether return news and dividend news are both computed directly or one of them is backed out as a residual....

  2. Recovery plan for Chorizanthe robusta var. robusta (Robust Spineflower)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Current Status: Chorizanthe robusta var. robusta (robust spineflower), which is federally endangered, is restricted to sandy soils along the coast and near-coastal...

  3. VAr reserve concept applied to a wind power plant

    DEFF Research Database (Denmark)

    Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

    2011-01-01

    a VAr management system are proposed and analyzed. Such a reactive power reserve may be provided by the wind power plant since the amount of reactive power installed for most active power working points exceeds the demand required by the grid operator. Basically, this overrated reactive power capacity......Larger percentages of wind power penetration translate into more demanding requirements from the grid codes; for example voltage support at the point of connection has been introduced recently by several grid codes from around the world, making it important to analyze this control when applied...... to wind power plants. This paper proposes two different VAr reserve control strategies for a wind power plant. The amount of dynamic VAr available most of the operation time, makes the wind power plant (WPP) a good candidate to include a VAr reserve management system. Two different ways of implementing...

  4. Puccinia jaceae var.solstitialis teliospore priming on yellow starthistle

    Science.gov (United States)

    Following the introduction of Puccinia jaceae var. solstitialis to California for biological control of yellow starthistle (Centaurea solstitialis, Asteraceae), teliospores, pycnia, and multiple urediniospore generations have been observed in the field. Because urediniospores have a relatively short...

  5. Orientation of the Fiscal Policy in Tunisia: Structural VAR Analysis

    Directory of Open Access Journals (Sweden)

    Wissem Khanfir

    2017-06-01

    Full Text Available The objective of this paper is to indicate the orientation of fiscal policy in Tunisia, using the structural budget balance, during the period 1972-2014. For this purpose, we estimate a structural VAR model consisting of the fiscal deficit to current GDP ratio and the volume of economic activity represented by the real GDP. We estimate bivariate structural VAR in order to decompose fiscal deficit fluctuations into different disturbances.

  6. VAR Methodology Used for Exchange Risk Measurement and Prevention

    Directory of Open Access Journals (Sweden)

    Florentina Balu

    2006-05-01

    Full Text Available In this article we discuss one of the modern risk measuring techniques Value-at-Risk (VaR. Currently central banks in major money centers, under the auspices of the BIS Basle Committee, adopt the VaR system to evaluate the market risk of their supervised banks. Banks regulators ask all commercial banks to report VaRs with their internal models. Value at risk (VaR is a powerful tool for assessing market risk, but it also imposes a challenge. Its power is its generality. Unlike market risk metrics such as the Greeks, duration and convexity, or beta, which are applicable to only certain asset categories or certain sources of market risk, VaR is general. It is based on the probability distribution for a portfolio’s market value. Value at Risk (VAR calculates the maximum loss expected (or worst case scenario on an investment, over a given time period and given a specified degree of confidence. There are three methods by which VaR can be calculated: the historical simulation, the variance-covariance method and the Monte Carlo simulation. The variance-covariance method is easiest because you need to estimate only two factors: average return and standard deviation. However, it assumes returns are well-behaved according to the symmetrical normal curve and that historical patterns will repeat into the future. The historical simulation improves on the accuracy of the VAR calculation, but requires more computational data; it also assumes that “past is prologue”. The Monte Carlo simulation is complex, but has the advantage of allowing users to tailor ideas about future patterns that depart from historical patterns.

  7. VAR Methodology Used for Exchange Risk Measurement and Prevention

    Directory of Open Access Journals (Sweden)

    Ion Stancu

    2006-03-01

    Full Text Available In this article we discuss one of the modern risk measuring techniques Value-at-Risk (VaR. Currently central banks in major money centers, under the auspices of the BIS Basle Committee, adopt the VaR system to evaluate the market risk of their supervised banks. Banks regulators ask all commercial banks to report VaRs with their internal models. Value at risk (VaR is a powerful tool for assessing market risk, but it also imposes a challenge. Its power is its generality. Unlike market risk metrics such as the Greeks, duration and convexity, or beta, which are applicable to only certain asset categories or certain sources of market risk, VaR is general. It is based on the probability distribution for a portfolio’s market value. Value at Risk (VAR calculates the maximum loss expected (or worst case scenario on an investment, over a given time period and given a specified degree of confidence. There are three methods by which VaR can be calculated: the historical simulation, the variance-covariance method and the Monte Carlo simulation. The variance-covariance method is easiest because you need to estimate only two factors: average return and standard deviation. However, it assumes returns are well-behaved according to the symmetrical normal curve and that historical patterns will repeat into the future. The historical simulation improves on the accuracy of the VAR calculation, but requires more computational data; it also assumes that “past is prologue”. The Monte Carlo simulation is complex, but has the advantage of allowing users to tailor ideas about future patterns that depart from historical patterns.

  8. Use of antigenic cartography in vaccine seed strain selection.

    Science.gov (United States)

    Fouchier, Ron A M; Smith, Derek J

    2010-03-01

    Human influenza A viruses are classic examples of antigenically variable pathogens that have a seemingly endless capacity to evade the host's immune response. The viral hemagglutinin (HA) and neuraminidase (NA) proteins are the main targets of our antibody response to combat infections. HA and NA continuously change to escape from humoral immunity, a process known as antigenic drift. As a result of antigenic drift, the human influenza vaccine is updated frequently. The World Health Organization (WHO) coordinates a global influenza surveillance network that, by the hemagglutination inhibition (HI) assay, routinely characterizes the antigenic properties of circulating strains in order to select new seed viruses for such vaccine updates. To facilitate a quantitative interpretation and easy visualization of HI data, a new computational technique called "antigenic cartography" was developed. Since its development, antigenic cartography has been applied routinely to assist the WHO with influenza surveillance activities. Until recently, antigenic variation was not considered a serious issue with influenza vaccines for poultry. However, because of the diversification of the Asian H5N1 lineage since 1996 into multiple genetic clades and subclades, and because of the long-term use of poultry vaccines against H5 in some parts of the world, this issue needs to be re-addressed. The antigenic properties of panels of avian H5N1 viruses were characterized by HI assay, using mammalian or avian antisera, and analyzed using antigenic cartography methods. These analyses revealed antigenic differences between circulating H5N1 viruses and the H5 viruses used in poultry vaccines. Considerable antigenic variation was also observed within and between H5N1 clades. These observations have important implications for the efficacy and long-term use of poultry vaccines.

  9. Sequence Variations in the Flagellar Antigen Genes fliCH25 and fliCH28 of Escherichia coli and Their Use in Identification and Characterization of Enterohemorrhagic E. coli (EHEC O145:H25 and O145:H28.

    Directory of Open Access Journals (Sweden)

    Lothar Beutin

    Full Text Available Enterohemorrhagic E. coli (EHEC serogroup O145 is regarded as one of the major EHEC serogroups involved in severe infections in humans. EHEC O145 encompasses motile and non-motile strains of serotypes O145:H25 and O145:H28. Sequencing the fliC-genes associated with the flagellar antigens H25 and H28 revealed the genetic diversity of the fliCH25 and fliCH28 gene sequences in E. coli. Based on allele discrimination of these fliC-genes real-time PCR tests were designed for identification of EHEC O145:H25 and O145:H28. The fliCH25 genes present in O145:H25 were found to be very similar to those present in E. coli serogroups O2, O100, O165, O172 and O177 pointing to their common evolution but were different from fliCH25 genes of a multiple number of other E. coli serotypes. In a similar way, EHEC O145:H28 harbor a characteristic fliCH28 allele which, apart from EHEC O145:H28, was only found in enteropathogenic (EPEC O28:H28 strains that shared some common traits with EHEC O145:H28. The real time PCR-assays targeting these fliCH25[O145] and fliCH28[O145] alleles allow better characterization of EHEC O145:H25 and EHEC O145:H28. Evaluation of these PCR assays in spiked ready-to eat salad samples resulted in specific detection of both types of EHEC O145 strains even when low spiking levels of 1-10 cfu/g were used. Furthermore these PCR assays allowed identification of non-motile E. coli strains which are serologically not typable for their H-antigens. The combined use of O-antigen genotyping (O145wzy and detection of the respective fliCH25[O145] and fliCH28[O145] allele types contributes to improve identification and molecular serotyping of E. coli O145 isolates.

  10. Sequence Variations in the Flagellar Antigen Genes fliCH25 and fliCH28 of Escherichia coli and Their Use in Identification and Characterization of Enterohemorrhagic E. coli (EHEC) O145:H25 and O145:H28

    Science.gov (United States)

    Beutin, Lothar; Delannoy, Sabine; Fach, Patrick

    2015-01-01

    Enterohemorrhagic E. coli (EHEC) serogroup O145 is regarded as one of the major EHEC serogroups involved in severe infections in humans. EHEC O145 encompasses motile and non-motile strains of serotypes O145:H25 and O145:H28. Sequencing the fliC-genes associated with the flagellar antigens H25 and H28 revealed the genetic diversity of the fliCH25 and fliCH28 gene sequences in E. coli. Based on allele discrimination of these fliC-genes real-time PCR tests were designed for identification of EHEC O145:H25 and O145:H28. The fliCH25 genes present in O145:H25 were found to be very similar to those present in E. coli serogroups O2, O100, O165, O172 and O177 pointing to their common evolution but were different from fliCH25 genes of a multiple number of other E. coli serotypes. In a similar way, EHEC O145:H28 harbor a characteristic fliCH28 allele which, apart from EHEC O145:H28, was only found in enteropathogenic (EPEC) O28:H28 strains that shared some common traits with EHEC O145:H28. The real time PCR-assays targeting these fliCH25[O145] and fliCH28[O145] alleles allow better characterization of EHEC O145:H25 and EHEC O145:H28. Evaluation of these PCR assays in spiked ready-to eat salad samples resulted in specific detection of both types of EHEC O145 strains even when low spiking levels of 1–10 cfu/g were used. Furthermore these PCR assays allowed identification of non-motile E. coli strains which are serologically not typable for their H-antigens. The combined use of O-antigen genotyping (O145wzy) and detection of the respective fliCH25[O145] and fliCH28[O145] allele types contributes to improve identification and molecular serotyping of E. coli O145 isolates. PMID:26000885

  11. Sequence Variations in the Flagellar Antigen Genes fliCH25 and fliCH28 of Escherichia coli and Their Use in Identification and Characterization of Enterohemorrhagic E. coli (EHEC) O145:H25 and O145:H28.

    Science.gov (United States)

    Beutin, Lothar; Delannoy, Sabine; Fach, Patrick

    2015-01-01

    Enterohemorrhagic E. coli (EHEC) serogroup O145 is regarded as one of the major EHEC serogroups involved in severe infections in humans. EHEC O145 encompasses motile and non-motile strains of serotypes O145:H25 and O145:H28. Sequencing the fliC-genes associated with the flagellar antigens H25 and H28 revealed the genetic diversity of the fliCH25 and fliCH28 gene sequences in E. coli. Based on allele discrimination of these fliC-genes real-time PCR tests were designed for identification of EHEC O145:H25 and O145:H28. The fliCH25 genes present in O145:H25 were found to be very similar to those present in E. coli serogroups O2, O100, O165, O172 and O177 pointing to their common evolution but were different from fliCH25 genes of a multiple number of other E. coli serotypes. In a similar way, EHEC O145:H28 harbor a characteristic fliCH28 allele which, apart from EHEC O145:H28, was only found in enteropathogenic (EPEC) O28:H28 strains that shared some common traits with EHEC O145:H28. The real time PCR-assays targeting these fliCH25[O145] and fliCH28[O145] alleles allow better characterization of EHEC O145:H25 and EHEC O145:H28. Evaluation of these PCR assays in spiked ready-to eat salad samples resulted in specific detection of both types of EHEC O145 strains even when low spiking levels of 1-10 cfu/g were used. Furthermore these PCR assays allowed identification of non-motile E. coli strains which are serologically not typable for their H-antigens. The combined use of O-antigen genotyping (O145wzy) and detection of the respective fliCH25[O145] and fliCH28[O145] allele types contributes to improve identification and molecular serotyping of E. coli O145 isolates.

  12. [Responses of Pinus sylvestris var. mongolica radial growth to climate warming in Great Xing' an Mountins: a case study in Mangui].

    Science.gov (United States)

    Zhang, Xing-Liang; He, Xing-Yuan; Chen, Zhen-Ju; Cui, Ming-Xing; Li, Na

    2011-12-01

    Based on the theory and methodology of dendrochronology, the tree ring width chronology of Pinus sylvestris var. mongolica in Mangui of Great Xing' an Mountains was developed, and the relationships between the standardized tree ring width chronology and local climate factors (temperature and precipitation) as well as the effects of climate factors on the P. sylvestris var. mongolica radial growth were analyzed. In this region, the mean monthly temperature in April-August of current year was the main factor limiting the radial growth, and the increasing mean monthly temperature from April to August had negative effects to the radial growth. The simulation of the variations of the radial growth by the mean monthly temperature change in April-August showed that the radial growth of P. sylvestris var. mongolica would present a declining trend accompanied with the warmer and drier regional climate condition.

  13. The complete chloroplast genome of Capsicum annuum var. glabriusculum using Illumina sequencing.

    Science.gov (United States)

    Raveendar, Sebastin; Na, Young-Wang; Lee, Jung-Ro; Shim, Donghwan; Ma, Kyung-Ho; Lee, Sok-Young; Chung, Jong-Wook

    2015-07-20

    Chloroplast (cp) genome sequences provide a valuable source for DNA barcoding. Molecular phylogenetic studies have concentrated on DNA sequencing of conserved gene loci. However, this approach is time consuming and more difficult to implement when gene organization differs among species. Here we report the complete re-sequencing of the cp genome of Capsicum pepper (Capsicum annuum var. glabriusculum) using the Illumina platform. The total length of the cp genome is 156,817 bp with a 37.7% overall GC content. A pair of inverted repeats (IRs) of 50,284 bp were separated by a small single copy (SSC; 18,948 bp) and a large single copy (LSC; 87,446 bp). The number of cp genes in C. annuum var. glabriusculum is the same as that in other Capsicum species. Variations in the lengths of LSC; SSC and IR regions were the main contributors to the size variation in the cp genome of this species. A total of 125 simple sequence repeat (SSR) and 48 insertions or deletions variants were found by sequence alignment of Capsicum cp genome. These findings provide a foundation for further investigation of cp genome evolution in Capsicum and other higher plants.

  14. The Complete Chloroplast Genome of Capsicum annuum var. glabriusculum Using Illumina Sequencing

    Directory of Open Access Journals (Sweden)

    Sebastin Raveendar

    2015-07-01

    Full Text Available Chloroplast (cp genome sequences provide a valuable source for DNA barcoding. Molecular phylogenetic studies have concentrated on DNA sequencing of conserved gene loci. However, this approach is time consuming and more difficult to implement when gene organization differs among species. Here we report the complete re-sequencing of the cp genome of Capsicum pepper (Capsicum annuum var. glabriusculum using the Illumina platform. The total length of the cp genome is 156,817 bp with a 37.7% overall GC content. A pair of inverted repeats (IRs of 50,284 bp were separated by a small single copy (SSC; 18,948 bp and a large single copy (LSC; 87,446 bp. The number of cp genes in C. annuum var. glabriusculum is the same as that in other Capsicum species. Variations in the lengths of LSC; SSC and IR regions were the main contributors to the size variation in the cp genome of this species. A total of 125 simple sequence repeat (SSR and 48 insertions or deletions variants were found by sequence alignment of Capsicum cp genome. These findings provide a foundation for further investigation of cp genome evolution in Capsicum and other higher plants.

  15. The complete chloroplast genome sequence of Gentiana lawrencei var. farreri (Gentianaceae and comparative analysis with its congeneric species

    Directory of Open Access Journals (Sweden)

    Peng-Cheng Fu

    2016-09-01

    Full Text Available Background The chloroplast (cp genome is useful in plant systematics, genetic diversity analysis, molecular identification and divergence dating. The genus Gentiana contains 362 species, but there are only two valuable complete cp genomes. The purpose of this study is to report the characterization of complete cp genome of G. lawrencei var. farreri, which is endemic to the Qinghai-Tibetan Plateau (QTP. Methods Using high throughput sequencing technology, we got the complete nucleotide sequence of the G. lawrencei var. farreri cp genome. The comparison analysis including genome difference and gene divergence was performed with its congeneric species G. straminea. The simple sequence repeats (SSRs and phylogenetics were studied as well. Results The cp genome of G. lawrencei var. farreri is a circular molecule of 138,750 bp, containing a pair of 24,653 bp inverted repeats which are separated by small and large single-copy regions of 11,365 and 78,082 bp, respectively. The cp genome contains 130 known genes, including 85 protein coding genes (PCGs, eight ribosomal RNA genes and 37 tRNA genes. Comparative analyses indicated that G. lawrencei var. farreri is 10,241 bp shorter than its congeneric species G. straminea. Four large gaps were detected that are responsible for 85% of the total sequence loss. Further detailed analyses revealed that 10 PCGs were included in the four gaps that encode nine NADH dehydrogenase subunits. The cp gene content, order and orientation are similar to those of its congeneric species, but with some variation among the PCGs. Three genes, ndhB, ndhF and clpP, have high nonsynonymous to synonymous values. There are 34 SSRs in the G. lawrencei var. farreri cp genome, of which 25 are mononucleotide repeats: no dinucleotide repeats were detected. Comparison with the G. straminea cp genome indicated that five SSRs have length polymorphisms and 23 SSRs are species-specific. The phylogenetic analysis of 48 PCGs from 12 Gentianales

  16. COMPARATIVE STUDIES ON ANTHELMINTIC ACTIVITY OF MANGIFERA INDICA L. VAR. THOTAPURI AND MANGIFERA INDICA L. VAR. NEELAM ROOT CRUDE EXTRACTS

    OpenAIRE

    Latha, M. S.

    2012-01-01

    Pet ether, ethyl acetate and ethanolic extracts of Mangifera indica L. Var. Thotapuri and Mangifera indica L. Var. Neelam were taken for anthelmintic activity against Indian earthworm Pheritima posthuma. Various concentrations of both extracts were tested and results were expressed in terms of time for evoked response, paralysis and time for death of worms. Piperazine citrate was used as a reference standard and distilled water as a control group. Dose dependent activity was observed in both ...

  17. The humoral response to Plasmodium falciparum VarO rosetting variant and its association with protection against malaria in Beninese children

    Directory of Open Access Journals (Sweden)

    Bentley Graham

    2010-10-01

    Full Text Available Abstract Background The capacity of Plasmodium falciparum-infected erythrocytes to bind uninfected erythrocytes (rosetting is associated with severe malaria in African children. Rosetting is mediated by a subset of the variant surface antigens PfEMP1 targeted by protective antibody responses. Analysis of the response to rosette-forming parasites and their PfEMP1 adhesive domains is essential for understanding the acquisition of protection against severe malaria. To this end, the antibody response to a rosetting variant was analysed in children recruited with severe or uncomplicated malaria or asymptomatic P. falciparum infection. Methods Serum was collected from Beninese children with severe malaria, uncomplicated malaria or P. falciparum asymptomatic infection (N = 65, 37 and 52, respectively and from immune adults (N = 30 living in the area. Infected erythrocyte surface-reactive IgG, rosette disrupting antibodies and IgG to the parasite crude extract were analysed using the single variant Palo Alto VarO-infected line. IgG, IgG1 and IgG3 to PfEMP1-varO-derived NTS-DBL1α1, CIDRγ and DBL2βC2 recombinant domains were analysed by ELISA. Antibody responses were compared in the clinical groups. Stability of the response was studied using a blood sampling collected 14 months later from asymptomatic children. Results Seroprevalence of erythrocyte surface-reactive IgG was high in adults (100% and asymptomatic children (92.3% but low in children with severe or uncomplicated malaria (26.1% and 37.8%, respectively. The IgG, IgG1 and IgG3 antibody responses to the varO-derived PfEMP1 domains were significantly higher in asymptomatic children than in children with clinical malaria in a multivariate analysis correcting for age and parasite density at enrolment. They were essentially stable, although levels tended to decrease with time. VarO-surface reactivity correlated positively with IgG reactivity to the rosetting domain varO-NTS-DBL1α1. None of the

  18. Strong suppression of $\\varUpsilon$ excited states in PbPb collisions at $\\sqrt{s_{NN}} = 5.02~\\mathrm{TeV}$

    CERN Document Server

    CMS Collaboration

    2016-01-01

    Measurements of $\\varUpsilon$ mesons, produced in pp and PbPb collisions at $\\sqrt{s_{NN}} = 5.02~\\mathrm{TeV}$ and reconstructed via their dimuon decay channel, are reported using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states to the ground state in both PbPb and pp collisions at the same energy. The $\\varUpsilon$(2S) double ratio is studied as a function of centrality, dimuon transverse momentum, and rapidity. We find suppression in all centrality bins and no variation with kinematics. For the $\\varUpsilon$(3S), no significant signal is found in the PbPb data. A search in centrality bins shows that the double ratio is significantly below unity at all centralities, an observation that indicates strong suppression in heavy-ion collisions. The centrality-integrated double ratios are $0.308 \\pm 0.055 \\mathrm{(stat)} \\pm 0.017 \\mathrm{(syst)}$ for the $\\varUpsilon$(2S) and less than $0.26$ at $95\\%$ confidence level for the $\\varUpsilon$(3S).

  19. Atypical disseminated cutaneous histoplasmosis in an immunocompetent child, caused by an "aberrant" variant of Histoplasma capsulatum var. capsulatum

    Directory of Open Access Journals (Sweden)

    LACAZ Carlos da Silva

    1999-01-01

    Full Text Available A case of atypical disseminated cutaneous histoplasmosis in a five-year old, otherwise healthy child, native and resident in São Paulo metropolitan area is reported. Cutaneous lesions were clinically atypical. Histologic examination disclosed a granulomatous reaction but no fungal structures could be demonstrated by specific staining nor by immunohistochemical reaction. The fungus was isolated from biopsy material on two different occasions, confirming diagnosis of an unusual fungal infection. The fungus, originally thought to be a Sepedonium sp. due to the large sized, hyaline or brownish colored tuberculated macroconidia and to lack of dimorphism (yeast form at 37 °C produce H and M antigens, visualized by the immunodiffusion with rabbit anti-Histoplasma capsulatum hyperimmune serum. Patient?s serum sample was non reactive with H. capsulatum antigen by immunodiffusion, counterimmunoelectrophoresis and complement fixation tests, and immunoenzymatic assay failed to detect the specific circulating antigen. This serum was tested negative by double immunodiffusion when antigen obtained from one of the isolated samples was used. Both cultures were sent to Dr. Leo Kaufman, Ph.D. (Mycoses Immunodiagnostic Laboratory, CDC-Atlanta/USA, who identified them as H. capsulatum by the exoantigen and gen-probe tests. Both clinic and mycologic characteristics of the present case were atypical, suggesting the fungus isolated is an ?aberrant variant? of H. capsulatum var. capsulatum, as described by SUTTON et al. in 199719. Treatment with itraconazole 100 mg/day led to cure within 90 days

  20. Transcutaneous antigen delivery system

    Directory of Open Access Journals (Sweden)

    Mi-Young Lee

    2013-01-01

    Full Text Available Transcutaneous immunization refers to the topical applicationof antigens onto the epidermis. Transcutaneous immunizationtargeting the Langerhans cells of the skin has received muchattention due to its safe, needle-free, and noninvasive antigendelivery. The skin has important immunological functions withunique roles for antigen-presenting cells such as epidermalLangerhans cells and dermal dendritic cells. In recent years,novel vaccine delivery strategies have continually beendeveloped; however, transcutaneous immunization has not yetbeen fully exploited due to the penetration barrier representedby the stratum corneum, which inhibits the transport ofantigens and adjuvants. Herein we review recent achievementsin transcutaneous immunization, focusing on the variousstrategies for the enhancement of antigen delivery andvaccination efficacy. [BMB Reports 2013; 46(1: 17-24

  1. On the variational data assimilation problem solving and sensitivity analysis

    Science.gov (United States)

    Arcucci, Rossella; D'Amore, Luisa; Pistoia, Jenny; Toumi, Ralf; Murli, Almerico

    2017-04-01

    We consider the Variational Data Assimilation (VarDA) problem in an operational framework, namely, as it results when it is employed for the analysis of temperature and salinity variations of data collected in closed and semi closed seas. We present a computing approach to solve the main computational kernel at the heart of the VarDA problem, which outperforms the technique nowadays employed by the oceanographic operative software. The new approach is obtained by means of Tikhonov regularization. We provide the sensitivity analysis of this approach and we also study its performance in terms of the accuracy gain on the computed solution. We provide validations on two realistic oceanographic data sets.

  2. Antiviral efficacy against hepatitis B virus replication of oleuropein isolated from Jasminum officinale L. var. grandiflorum.

    Science.gov (United States)

    Zhao, Guiqin; Yin, Zhifeng; Dong, Junxing

    2009-09-07

    Jasminum officinale L. var. grandiflorum (JOG) is a folk medicine used for the treatment of hepatitis in south of China. Phytochemical studies showed that secoiridoid glycosides are the typical constituents of this plant. The present study was undertaken to evaluate the effect of oleuropein (Ole) derived from the flowers of JOG on hepatitis B virus (HBV) replication in HepG2 2.2.15 cell line in vitro and duck hepatitis B virus (DHBV) replication in ducklings in vivo. The extracellular hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) concentrations in cell culture medium were determined by ELISA. DHBV in duck serum was analyzed by dot blot. Ole blocks effectively HBsAg secretion in HepG2 2.2.15 cells in a dose-dependent manner (IC(50)=23.2 microg/ml). Ole (80 mg/kg, intraperitoneally, twice daily) also reduced viremia in DHBV-infected ducks. Ole therefore warrants further investigation as a potential therapeutic agent for HBV infection.

  3. Anti-hepatitis B Virus Activity of 8-epi-Kingiside in Jasminum officinale var. grandiflorum

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Gui-qin; YIN; Zhi-feng; LIU; Li-yan; MAO; Xiao-xia; SU; Zhan-hui

    2013-01-01

    Objective To evaluate the effect of 8-epi-kingiside (8-Epik) derived from the buds of Jasminum officinale var. grandiflorum (JOG) on hepatitis B virus (HBV) replication in HepG2 2.2.15 cell line in vitro and duck hepatitis B virus (DHBV) replication in ducklings in vivo. Methods The concentration of extracellular hepatitis B e antigen and hepatitis B surface antigen (HBsAg) in cell culture medium was determined by ELISA, respectively. The anti-HBV effects of 8-Epik were also demonstrated in the model of DHBV. 8-Epik was ip given (20, 40, and 80 mg/kg, twice daily) to the DHBV-infected ducklings for 10 d. The isotonic saline liquid diet was ip given as negative control and Lamivudine (50 mg/kg, twice daily) was given as positive control. DHBV DNA was measured at days 0 (T0), 5 (T5), 10 (T10), and day 3 after cessation of treatment (P3) by dot blotting. Results 8-Epik effectively blocked HBsAg secretion in HepG2 2.2.15 cells in a dose-dependent manner [IC 50 = (19.4 ± 1.04) μg/mL]. 8-Epik (40 or 80 mg/kg, ip, twice daily) also reduced viremia in DHBV-infected ducks. Conclusion Therefore, 8-Epik is warranted as a potential therapeutic agent for HBV infection.

  4. A clarified position for solanum lycopersicum var. cerasiforme in the evolutionary history of tomatoes (solanaceae

    Directory of Open Access Journals (Sweden)

    Causse Mathilde

    2008-12-01

    Full Text Available Abstract Background The natural phenotypic variability present in the germplasm of cultivated plants can be linked to molecular polymorphisms using association genetics. However it is necessary to consider the genetic structure of the germplasm used to avoid false association. The knowledge of genetic structure of plant populations can help in inferring plant evolutionary history. In this context, we genotyped 360 wild, feral and cultivated accessions with 20 simple sequence repeat markers and investigated the extent and structure of the genetic variation. The study focused on the red fruited tomato clade involved in the domestication of tomato and confirmed the admixture status of cherry tomatoes (Solanum lycopersicum var. cerasiforme. We used a nested sample strategy to set-up core collection maximizing the genetic diversity with a minimum of individuals. Results Molecular diversity was considerably lower in S. lycopersicum i.e. the domesticated form. Model-based analysis showed that the 144 S. lycopersicum var. cerasiforme accessions were structured into two groups: one close to the domesticated group and one resulting from the admixture of the S. lycopersicum and S. pimpinellifolium genomes. SSR genotyping also indicates that domesticated and wild tomatoes have evolved as a species complex with intensive level of hybridization. We compiled genotypic and phenotypic data to identify sub-samples of 8, 24, 32 and 64 cherry tomato accessions that captured most of the genetic and morphological diversity present in the entire S. lycopersicum var. cerasiforme collection. Conclusion The extent and structure of allelic variation is discussed in relation to historical events like domestication and modern selection. The potential use of the admixed group of S. lycopersicum var. cerasiforme for association genetics studies is also discussed. Nested core collections sampled to represent tomato diversity will be useful in diversity studies. Molecular and

  5. Identification of Local Melon (Cucumis melo L. var. Bartek Based on Chromosomal Characters

    Directory of Open Access Journals (Sweden)

    BUDI SETIADI DARYONO

    2011-12-01

    Full Text Available Bartek is one of local melon varieties mainly cultivated in Pemalang, Central Java. Bartek has three variations of fruits; Long-Green, Ellips-Green, and Yellow. Chromosome characterization of the Bartek was investigated to determine the genetic variation. The main purpose of this research was to determine the genetic characters of Bartek including chromosome number, mitosis, cell cycle, and karyotype. Squash method was used for chromosome preparation. The results showed that all of Bartek observed in this study have similar diploid (2n chromosome number = 24. According to the total number of chromosome, Bartek is closer to melon than cucumber. The mitotic analysis exhibited that the Bartek has similar karyotype formula, 2n = 2x = 24m. Based on the R value of the three kinds of Bartek (R < 0.27, it indicated that three kinds of Bartek were considered to be originated from similar species and one of melon varieties (Cucumis melo L. var. Bartek.

  6. Static Var Compensator based on Fuzzy Logic Control for Damping Power System Oscillation

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2011-01-01

    Full Text Available Problem statement: The disturbance in power system is unavoidable situation. It causes in power system oscillation. Approach: This study applied the Static Var Compensator (SVC to damp power system oscillation. The fuzzy logic control is applied to determine the control strategy of SVC. The simulation results are tested on a Single Machine Infinite bus. The proposed method is equipped in sample system with disturbance. The generator rotor angle curve of the system without and with a SVC is plotted and compared. Results: It was found that the system without a SVC has high variation whereas that of the system with a SVC has much smaller variation. Conclusion: From the simulation results, the SVC can damp power system oscillation.

  7. Application Lyapunov Theory to Determine Control Strategy of Static Var Compensator for Damping Power System Oscillation

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2011-01-01

    Full Text Available Problem statement: The disturbance in power system is unavoidable situation. It causes in power system oscillation. Approach: This study applied the Static Var Compensator (SVC to damp power system oscillation. The stability criterion of the Lyapunov is applied to derive the control strategy of SVC. The simulation results are tested on a Single Machine Infinite bus. The proposed method is equipped in sample system with disturbance. The generator rotor angle curve of the system without and with a SVC is plotted and compared for various cases. Results: It was found that the system without a SVC has high variation whereas that of the system with a SVC has much smaller variation. Conclusion: From the simulation results, the SVC can damp power system oscillaton.

  8. 1D+4D-VAR data assimilation of lightning with WRFDA system using nonlinear observation operators

    CERN Document Server

    Stefanescu, Razvan; Fuelberg, Henry; Marchand, Max

    2013-01-01

    This paper addresses the impact of assimilating data from the Earth Networks Total Lightning Network (ENTLN) during two cases of severe weather. Data from the ENTLN serve as a substitute for those from the upcoming launch of the GOES Lightning Mapper (GLM). We use the Weather Research and Forecast (WRF) model and variational data assimilation techniques at 9 km spatial resolution. The main goal is to examine the potential impact of lightning observations from the future GLM. Previous efforts to assimilate lightning observations mainly utilized nudging approaches. We develop three more sophisticated approaches, 3D-VAR WRFDA and 1D+nD-VAR (n=3,4) WRFDA schemes that currently are being considered for operational implementation by the National Centers for Environmental Prediction (NCEP) and the Naval Research Laboratory (NRL). This research uses Convective Available Potential Energy (CAPE) as a proxy between lightning data and model variables. To test the performance of the aforementioned schemes, we assess the q...

  9. Volatile and Flavonoid Composition of the Peel of Citrus medica L. var. Corsican Fruit for Quality Assessment of Its Liqueur

    Science.gov (United States)

    Venturini, Nicolas; Barboni, Toussaint; Curk, Franck; Costa, Jean

    2014-01-01

    Summary The volatile and flavonoid compositions of the peel of Citrus medica L. var. Corsican fruits cultivated in Corsica were studied according to the maturity of the citron fruits measured using growing degree-days. Quantitative variation with the stage of development of the fruit was observed using gas chromatography, gas chromatography-mass spectrometry, and liquid chromatography-mass spectrometry/mass spectrometry. Thirty volatile compounds were identified in the peel essential oil. Limonene and γ-terpinene were the major compounds. The volatile compositions of commercial citron liqueurs were also characterized by high amounts of monoterpene hydrocarbons with the same two major components. The main flavonoid components of citron fruits and derived liqueurs were rutin and neohesperidin. This chemical characterization can be used for quality assessment of food products from C. medica var. Corsican. PMID:27904313

  10. Antigenic Relationships among Human Pathogenic Orientia tsutsugamushi Isolates from Thailand

    Science.gov (United States)

    Nawtaisong, Pruksa; Tanganuchitcharnchai, Ampai; Smith, Derek J.; Day, Nicholas P. J.; Paris, Daniel H.

    2016-01-01

    Background Scrub typhus is a common cause of undiagnosed febrile illness in certain tropical regions, but can be easily treated with antibiotics. The causative agent, Orientia tsutsugamushi, is antigenically variable which complicates diagnosis and efforts towards vaccine development. Methodology/Principal Findings This study aimed to dissect the antigenic and genetic relatedness of O. tsutsugamushi strains and investigate sero-diagnostic reactivities by titrating individual patient sera against their O. tsutsugamushi isolates (whole-cell antigen preparation), in homologous and heterologous serum-isolate pairs from the same endemic region in NE Thailand. The indirect immunofluorescence assay was used to titrate Orientia tsutsugamushi isolates and human sera, and a mathematical technique, antigenic cartography, was applied to these data to visualise the antigenic differences and cross-reactivity between strains and sera. No functional or antigen-specific analyses were performed. The antigenic variation found in clinical isolates was much less pronounced than the genetic differences found in the 56kDa type-specific antigen genes. The Karp-like sera were more broadly reactive than the Gilliam-like sera. Conclusions/Significance Antigenic cartography worked well with scrub typhus indirect immunofluorescence titres. The data from humoral responses suggest that a Karp-like strain would provide broader antibody cross-reactivity than a Gilliam-like strain. Although previous exposure to O. tsutsugamushi could not be ruled out, scrub typhus patient serum antibody responses were characterised by strong homologous, but weak heterologous antibody titres, with little evidence for cross-reactivity by Gilliam-like sera, but a broader response from some Karp-like sera. This work highlights the importance of antigenic variation in O. tsutsugamushi diagnosis and determination of new serotypes. PMID:27248711

  11. Antigenic Relationships among Human Pathogenic Orientia tsutsugamushi Isolates from Thailand.

    Directory of Open Access Journals (Sweden)

    Sarah L James

    2016-06-01

    Full Text Available Scrub typhus is a common cause of undiagnosed febrile illness in certain tropical regions, but can be easily treated with antibiotics. The causative agent, Orientia tsutsugamushi, is antigenically variable which complicates diagnosis and efforts towards vaccine development.This study aimed to dissect the antigenic and genetic relatedness of O. tsutsugamushi strains and investigate sero-diagnostic reactivities by titrating individual patient sera against their O. tsutsugamushi isolates (whole-cell antigen preparation, in homologous and heterologous serum-isolate pairs from the same endemic region in NE Thailand. The indirect immunofluorescence assay was used to titrate Orientia tsutsugamushi isolates and human sera, and a mathematical technique, antigenic cartography, was applied to these data to visualise the antigenic differences and cross-reactivity between strains and sera. No functional or antigen-specific analyses were performed. The antigenic variation found in clinical isolates was much less pronounced than the genetic differences found in the 56kDa type-specific antigen genes. The Karp-like sera were more broadly reactive than the Gilliam-like sera.Antigenic cartography worked well with scrub typhus indirect immunofluorescence titres. The data from humoral responses suggest that a Karp-like strain would provide broader antibody cross-reactivity than a Gilliam-like strain. Although previous exposure to O. tsutsugamushi could not be ruled out, scrub typhus patient serum antibody responses were characterised by strong homologous, but weak heterologous antibody titres, with little evidence for cross-reactivity by Gilliam-like sera, but a broader response from some Karp-like sera. This work highlights the importance of antigenic variation in O. tsutsugamushi diagnosis and determination of new serotypes.

  12. SEVIRI 4D-var assimilation analysing the April 2010 Eyjafjallajökull ash dispersion

    Science.gov (United States)

    Lange, Anne Caroline; Elbern, Hendrik

    2016-04-01

    We present first results of four dimensional variational (4D-var) data assimilation analysis applying SEVIRI observations to the Eulerian regional chemistry and aerosol transport model EURAD-IM (European Air Pollution Dispersion - Inverse Model). Optimising atmospheric dispersion models in terms of volcanic ash transport predictions by observations is especially essential for the aviation industry and associated interests. Remote sensing satellite observations are instrumental for ash detection and monitoring. We choose volcanic ash column retrievals of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) because as infrared instrument on the geostationary satellite Meteosat Second Generation it delivers measurements with high temporal resolution during day and night. The retrieval method relies on the reverse absorption effect. In the framework of the national initiative ESKP (Earth System Knowledge Platform) and the European ACTRIS-2 (Aerosol, Clouds, and Trace gases Research InfraStructure) project, we developed new modules (forward and adjoint) within the EURAD-IM, which are able to process SEVIRI ash column data as observational input to the 4D-var system. The focus of the 4D-var analysis is on initial value optimisation of the volcanic ash clouds that were emitted during the explosive Eyjafjallajökull eruption in April 2010. This eruption caused high public interest because of air traffic closures and it was particularly well observed from many different observation systems all over Europe. Considering multiple observation periods simultaneously in one assimilation window generates a continuous trajectory in the phase space and ensures that past observations are considered within their uncertainties. Results are validated mainly by lidar (LIght Detection And Ranging) observations, both ground and satellite based.

  13. Mitotic evolution of Plasmodium falciparum shows a stable core genome but recombination in antigen families.

    Directory of Open Access Journals (Sweden)

    Selina E R Bopp

    Full Text Available Malaria parasites elude eradication attempts both within the human host and across nations. At the individual level, parasites evade the host immune responses through antigenic variation. At the global level, parasites escape drug pressure through single nucleotide variants and gene copy amplification events conferring drug resistance. Despite their importance to global health, the rates at which these genomic alterations emerge have not been determined. We studied the complete genomes of different Plasmodium falciparum clones that had been propagated asexually over one year in the presence and absence of drug pressure. A combination of whole-genome microarray analysis and next-generation deep resequencing (totaling 14 terabases revealed a stable core genome with only 38 novel single nucleotide variants appearing in seventeen evolved clones (avg. 5.4 per clone. In clones exposed to atovaquone, we found cytochrome b mutations as well as an amplification event encompassing the P. falciparum multidrug resistance associated protein (mrp1 on chromosome 1. We observed 18 large-scale (>1 kb on average deletions of telomere-proximal regions encoding multigene families, involved in immune evasion (9.5×10(-6 structural variants per base pair per generation. Six of these deletions were associated with chromosomal crossovers generated during mitosis. We found only minor differences in rates between genetically distinct strains and between parasites cultured in the presence or absence of drug. Using these derived mutation rates for P. falciparum (1.0-9.7×10(-9 mutations per base pair per generation, we can now model the frequency at which drug or immune resistance alleles will emerge under a well-defined set of assumptions. Further, the detection of mitotic recombination events in var gene families illustrates how multigene families can arise and change over time in P. falciparum. These results will help improve our understanding of how P. falciparum

  14. Identification of the varR gene as a transcriptional regulator of virginiamycin S resistance in Streptomyces virginiae.

    Science.gov (United States)

    Namwat, W; Lee, C K; Kinoshita, H; Yamada, Y; Nihira, T

    2001-03-01

    A gene designated varR (for virginiae antibiotic resistance regulator) was identified in Streptomyces virginiae 89 bp downstream of a varS gene encoding a virginiamycin S (VS)-specific transporter. The deduced varR product showed high homology to repressors of the TetR family with a conserved helix-turn-helix DNA binding motif. Purified recombinant VarR protein was present as a dimer in vitro and showed clear DNA binding activity toward the varS promoter region. This binding was abolished by the presence of VS, suggesting that VarR regulates transcription of varS in a VS-dependent manner. Northern blot analysis revealed that varR was cotranscribed with upstream varS as a 2.4-kb transcript and that VS acted as an inducer of bicistronic transcription. Deletion analysis of the varS promoter region clarified two adjacent VarR binding sites in the varS promoter.

  15. Bootstrap determination of the cointegration rank in heteroskedastic VAR models

    DEFF Research Database (Denmark)

    Cavaliere, Guiseppe; Rahbæk, Anders; Taylor, A.M. Robert

    2014-01-01

    -integrated VAR model with i.i.d. innovations. In this paper we investigate the properties of their bootstrap procedures, together with analogous procedures based on a wild bootstrap resampling scheme, when time-varying behavior is present in either the conditional or unconditional variance of the innovations. We...... the asymptotic PLR test or an alternative bootstrap method (where the short run dynamics in the VAR model are estimated unrestrictedly) for a variety of conditionally and unconditionally heteroskedastic innovation processes...... of the underlying vector autoregressive (VAR) model which obtain under the reduced rank null hypothesis. They propose methods based on an independent and individual distributed (i.i.d.) bootstrap resampling scheme and establish the validity of their proposed bootstrap procedures in the context of a co...

  16. EFFECTS OF MONETARY POLICY IN ROMANIA - A VAR APPROACH

    Directory of Open Access Journals (Sweden)

    Iulian Popescu

    2012-10-01

    Full Text Available Understanding how monetary policy decisions affect inflation and other economic variables is particularly important. In this paper we consider the implications of monetary policy under the inflation targeting regime in Romania, based on an autoregressive vector method including recursive VAR and structural VAR (SVAR. Therefore, we focus on assessing the extent and persistence of monetary policy effects on gross domestic product (GDP, price level, extended monetary aggregate (M3 and exchange rate. The main results of VAR analysis reflect a negative response of consumer price index (CPI, GDP and M3 and positive nominal exchange rate behaviour to a monetary policy shock, and also a limited impact of a short-term interest rate shock in explaining the consumer prices, production and exchange rate fluctuations.

  17. [Trichophyton tonsurans var. sulfureum subvar. perforans in Tinea gladiatorum].

    Science.gov (United States)

    Brasch, J; Rüther, T; Harmsen, D

    1999-05-01

    This is the first report on an isolation of Trichophyton tonsurans var.sulfureum subvar.perforans in Germany. In our patient, the strain had caused typical tinea corporis, which was most likely acquired during a wrestling competition. Based on the macroscopic and microscopic morphology and on the physiologic properties occurring under various growth conditions, the identification of Trichophyton tonsurans and the particular characteristics of its var.sulfureum subvar.perforans are described. Partial 18S and 23S nuclear ribosomal RNA sequences and the internal transcribed spacer region I sequences of our strain were completely identical with those of a Trichophyton tonsurans reference strain. The epidemiology of Trichophyton tonsurans var.sulfureum subvar.perforans and a possible association of this variety with tinea in wrestlers (tinea gladiatorum) have not yet been investigated.

  18. Extremum Seeking Control of Smart Inverters for VAR Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, Daniel; Negrete-Pincetic, Matias; Stewart, Emma; Auslander, David, M; Callaway, Duncan

    2015-09-04

    Reactive power compensation is used by utilities to ensure customer voltages are within pre-defined tolerances and reduce system resistive losses. While much attention has been paid to model-based control algorithms for reactive power support and Volt Var Optimization (VVO), these strategies typically require relatively large communications capabilities and accurate models. In this work, a non-model-based control strategy for smart inverters is considered for VAR compensation. An Extremum Seeking control algorithm is applied to modulate the reactive power output of inverters based on real power information from the feeder substation, without an explicit feeder model. Simulation results using utility demand information confirm the ability of the control algorithm to inject VARs to minimize feeder head real power consumption. In addition, we show that the algorithm is capable of improving feeder voltage profiles and reducing reactive power supplied by the distribution substation.

  19. THE BRINE SHRIMP (ARTEMIA SALINA) LETHALITY OF Brassica oleracea var. capitata

    OpenAIRE

    O.T. TÜZÜN, E. GÜRKAN, F. HIRLAK,

    2015-01-01

    This work covers up the bio-activities of the five fractions obtained from the ethanolic extract of Brassica oleracea var. capitata (Cruciferae).Key Words: Brassica oleracea var. capitata, Brine shrimp (Artemia salina)

  20. Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

    NARCIS (Netherlands)

    Ji, X.

    2014-01-01

    Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. The large genomic changes are important for

  1. Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

    NARCIS (Netherlands)

    Ji, X.

    2014-01-01

    Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. The large genomic changes are important for

  2. Meiotic chromosome pairing in Actinidia chinensis var. deliciosa.

    Science.gov (United States)

    Mertten, D; Tsang, G K; Manako, K I; McNeilage, M A; Datson, P M

    2012-12-01

    Polyploids are defined as either autopolyploids or allopolyploids, depending on their mode of origin and/or chromosome pairing behaviour. Autopolyploids have chromosome sets that are the result of the duplication or combination of related genomes (e.g., AAAA), while allopolyploids result from the combination of sets of chromosomes from two or more different taxa (e.g., AABB, AABBCC). Allopolyploids are expected to show preferential pairing of homologous chromosomes from within each parental sub-genome, leading to disomic inheritance. In contrast, autopolyploids are expected to show random pairing of chromosomes (non-preferential pairing), potentially leading to polysomic inheritance. The two main cultivated taxa of Actinidia (kiwifruit) are A. chinensis (2x and 4x) and A. chinensis var. deliciosa (6x). There is debate whether A. chinensis var. deliciosa is an autopolyploid derived solely from A. chinensis or whether it is an allopolyploid derived from A. chinensis and one or two other Actinidia taxa. To investigate whether preferential or non-preferential chromosome pairing occurs in A. chinensis var. deliciosa, the inheritance of microsatellite alleles was analysed in the tetraploid progeny of a cross between A. chinensis var. deliciosa and the distantly related Actinidia eriantha Benth. (2x). The frequencies of inherited microsatellite allelic combinations in the hybrids suggested that non-preferential chromosome pairing had occurred in the A. chinensis var. deliciosa parent. Meiotic chromosome analysis showed predominantly bivalent formation in A. chinensis var. deliciosa, but a low frequency of quadrivalent chromosome formations was observed (1 observed in 20 pollen mother cells).

  3. Conformational Dynamics and Antigenicity in the Disordered Malaria Antigen Merozoite Surface Protein 2

    Science.gov (United States)

    Andrew, Dean; Krishnarjuna, Bankala; Nováček, Jiří; Žídek, Lukáš; Sklenář, Vladimír; Richards, Jack S.; Beeson, James G.; Anders, Robin F.; Norton, Raymond S.

    2015-01-01

    Merozoite surface protein 2 (MSP2) of Plasmodium falciparum is an abundant, intrinsically disordered protein that is GPI-anchored to the surface of the invasive blood stage of the malaria parasite. Recombinant MSP2 has been trialled as a component of a malaria vaccine, and is one of several disordered proteins that are candidates for inclusion in vaccines for malaria and other diseases. Nonetheless, little is known about the implications of protein disorder for the development of an effective antibody response. We have therefore undertaken a detailed analysis of the conformational dynamics of the two allelic forms of MSP2 (3D7 and FC27) using NMR spectroscopy. Chemical shifts and NMR relaxation data indicate that conformational and dynamic properties of the N- and C-terminal conserved regions in the two forms of MSP2 are essentially identical, but significant variation exists between and within the central variable regions. We observe a strong relationship between the conformational dynamics and the antigenicity of MSP2, as assessed with antisera to recombinant MSP2. Regions of increased conformational order in MSP2, including those in the conserved regions, are more strongly antigenic, while the most flexible regions are minimally antigenic. This suggests that modifications that increase conformational order may offer a means to tune the antigenicity of MSP2 and other disordered antigens, with implications for vaccine design. PMID:25742002

  4. Conformational dynamics and antigenicity in the disordered malaria antigen merozoite surface protein 2.

    Directory of Open Access Journals (Sweden)

    Christopher A MacRaild

    Full Text Available Merozoite surface protein 2 (MSP2 of Plasmodium falciparum is an abundant, intrinsically disordered protein that is GPI-anchored to the surface of the invasive blood stage of the malaria parasite. Recombinant MSP2 has been trialled as a component of a malaria vaccine, and is one of several disordered proteins that are candidates for inclusion in vaccines for malaria and other diseases. Nonetheless, little is known about the implications of protein disorder for the development of an effective antibody response. We have therefore undertaken a detailed analysis of the conformational dynamics of the two allelic forms of MSP2 (3D7 and FC27 using NMR spectroscopy. Chemical shifts and NMR relaxation data indicate that conformational and dynamic properties of the N- and C-terminal conserved regions in the two forms of MSP2 are essentially identical, but significant variation exists between and within the central variable regions. We observe a strong relationship between the conformational dynamics and the antigenicity of MSP2, as assessed with antisera to recombinant MSP2. Regions of increased conformational order in MSP2, including those in the conserved regions, are more strongly antigenic, while the most flexible regions are minimally antigenic. This suggests that modifications that increase conformational order may offer a means to tune the antigenicity of MSP2 and other disordered antigens, with implications for vaccine design.

  5. DNA secondary structures are associated with recombination in major Plasmodium falciparum variable surface antigen gene families

    DEFF Research Database (Denmark)

    Sander, Adam F.; Lavstsen, Thomas; Rask, Thomas Salhøj

    2014-01-01

    -wide recombination hotspots in var genes, we show that during the parasite’s sexual stages, ectopic recombination between isogenous var paralogs occurs near low folding free energy DNA 50-mers and that these sequences are heavily concentrated at the boundaries of regions encoding individual Plasmodium falciparum......-erythrocyte membrane protein 1 structural domains. The recombinogenic potential of these 50-mers is not parasite-specific because these sequences also induce recombination when transferred to the yeast Saccharomyces cerevisiae. Genetic cross data suggest that DNA secondary structures (DSS) act as inducers...... of recombination during DNA replication in P. falciparum sexual stages, and that these DSS-regulated genetic exchanges generate functional and diverse P. falciparum adhesion antigens. DSS-induced recombination may represent a common mechanism for optimizing the evolvability of virulence gene families in pathogens....

  6. First Report of Cucumber mosaic virus Isolated from Wild Vigna angularis var. nipponensis in Korea

    Directory of Open Access Journals (Sweden)

    Mi-Kyeong Kim

    2014-06-01

    Full Text Available A viral disease causing severe mosaic, necrotic, and yellow symptoms on Vigna angularis var. nipponensis was prevalent around Suwon area in Korea. The causal virus was characterized as Cucumber mosaic virus (CMV on the basis of biological and nucleotide sequence properties of RNAs 1, 2 and 3 and named as CMV-wVa. CMV-wVa isolate caused mosaic symptoms on indicator plants, Nicotiana tabacum cv. Xanthi-nc, Petunia hybrida, and Cucumis sativus. Strikingly, CMV-wVa induced severe mosaic and malformation on Cucurbita pepo, and Solanum lycopersicum. Moreover, it caused necrotic or mosaic symptoms on V. angularis and V. radiate of Fabaceae. Symptoms of necrotic local or pin point were observed on inoculated leaves of V. unguiculata, Vicia fava, Pisum sativum and Phaseolus vulgaris. However, CMV-wVa isolate failed to infect in Glycine max cvs. ‘Sorok’, ‘Sodam’ and ‘Somyeong’. To assess genetic variation between CMV-wVa and the other known CMV isolates, phylogenetic analysis using 16 complete nucleotide sequences of CMV RNA1, RNA2, and RNA3 including CMV-wVa was performed. CMV-wVa was more closely related to CMV isolates belonging to CMV subgroup I showing about 85.1–100% nucleotide sequences identity to those of subgroup I isolates. This is the first report of CMV as the causal virus infecting wild Vigna angularis var. nipponensis in Korea.

  7. First Report of Cucumber mosaic virus Isolated from Wild Vigna angularis var. nipponensis in Korea.

    Science.gov (United States)

    Kim, Mi-Kyeong; Jeong, Rae-Dong; Kwak, Hae-Ryun; Lee, Su-Heon; Kim, Jeong-Soo; Kim, Kook-Hyung; Cha, Byeongjin; Choi, Hong-Soo

    2014-06-01

    A viral disease causing severe mosaic, necrotic, and yellow symptoms on Vigna angularis var. nipponensis was prevalent around Suwon area in Korea. The causal virus was characterized as Cucumber mosaic virus (CMV) on the basis of biological and nucleotide sequence properties of RNAs 1, 2 and 3 and named as CMV-wVa. CMV-wVa isolate caused mosaic symptoms on indicator plants, Nicotiana tabacum cv. Xanthi-nc, Petunia hybrida, and Cucumis sativus. Strikingly, CMV-wVa induced severe mosaic and malformation on Cucurbita pepo, and Solanum lycopersicum. Moreover, it caused necrotic or mosaic symptoms on V. angularis and V. radiate of Fabaceae. Symptoms of necrotic local or pin point were observed on inoculated leaves of V. unguiculata, Vicia fava, Pisum sativum and Phaseolus vulgaris. However, CMV-wVa isolate failed to infect in Glycine max cvs. 'Sorok', 'Sodam' and 'Somyeong'. To assess genetic variation between CMV-wVa and the other known CMV isolates, phylogenetic analysis using 16 complete nucleotide sequences of CMV RNA1, RNA2, and RNA3 including CMV-wVa was performed. CMV-wVa was more closely related to CMV isolates belonging to CMV subgroup I showing about 85.1-100% nucleotide sequences identity to those of subgroup I isolates. This is the first report of CMV as the causal virus infecting wild Vigna angularis var. nipponensis in Korea.

  8. Multiyear climate prediction with initialization based on 4D-Var data assimilation

    Science.gov (United States)

    Mochizuki, Takashi; Masuda, Shuhei; Ishikawa, Yoichi; Awaji, Toshiyuki

    2016-04-01

    An initialization relevant to interannual-to-decadal climate prediction has usually used a simple restoring approach for oceanic variables. Here we demonstrate the potential use of four-dimensional variational (4D-Var) data assimilation on the leading edge of initialization approach particularly in multiyear (5 year long) climate prediction. We perform full-field initialization rather than anomaly initialization and assimilate the atmosphere states together with the ocean states to an atmosphere-ocean coupled climate model. In particular, it is noteworthy that ensembles of multiyear hindcasts using our assimilation results as initial conditions exhibit an improved skill in hindcasting the multiyear changes of the upper ocean heat content (OHC) over the central North Pacific. The 4D-Var approach enables us to directly assimilate a time trajectory of slow changes of the Aleutian Low that are compatible with the sea surface height and the OHC. Consequently, we can estimate a coupled climate state suitable for hindcasting dynamical changes over the extratropical North Pacific as observed.

  9. Var C: Long-term photometric and spectral variability of an LBV in M33

    CERN Document Server

    Burggraf, B; Bomans, D J; Henze, M; Meusinger, H; Sholukhova, O; Zharova, A; Pellerin, A; Becker, A

    2015-01-01

    So far the highly unstable phase of luminous blue variables (LBVs) has not been understood well. It is still uncertain why and which massive stars enter this phase. Investigating the variabilities by looking for a possible regular or even (semi-)periodic behaviour could give a hint at the underlying mechanism for these variations and might answer the question of where these variabilities originate. Finding out more about the LBV phase also means understanding massive stars better in general, which have (e.g. by enriching the ISM with heavy elements, providing ionising radiation and kinetic energy) a strong and significant influence on the ISM, hence also on their host galaxy. Photometric and spectroscopic data were taken for the LBV Var C in M33 to investigate its recent status. In addition, scanned historic plates, archival data, and data from the literature were gathered to trace Var C's behaviour in the past. Its long-term variability and periodicity was investigated. Our investigation of the variability i...

  10. [Iridoid glycosides from buds of Jasminum officinale L. var. grandiflorum].

    Science.gov (United States)

    Zhao, Gui-qin; Yin, Zhi-feng; Liu, Yu-cui; Li, Hong-bo

    2011-10-01

    The study on the buds of Jasminum officinale L. var. grandiflorum was carried out to look for anti-HBV constituents. The isolation and purification were performed by HPLC and chromatography on silica gel, polyamide and Sephadex LH-20 column. The structures were elucidated on the basis of physicochemical properties and spectral analysis. Six iridoid glycosides were identified as jasgranoside B (1), 6-O-methy-catalpol (2), deacetyl asperulosidic acid (3), aucubin (4), 8-dehydroxy shanzhiside (5), and loganin (6). Jasgranoside B (1) is a new compound. Compounds 2-6 were isolated from Jasminum officinale L. var. grandiflorum for the first time.

  11. Typification of Blechnum spicant var. fallax Lange (Blechnaceae

    Directory of Open Access Journals (Sweden)

    Paweł Wąsowicz

    2017-03-01

    Full Text Available Blechnum spicant var. fallax Lange is a fern taxon endemic to Iceland where it occurs in the vicinity of hot springs on geothermally heated soils. The taxon was first described by a Danish botanist Johan Martin Christian Lange in 1880 on the basis of plant material collected by Christian Grønlund in Iceland. Because its holotype was not designated in the protologue, we examined the extant original material including illustrations from Flora Danica and a single plant on sheet C10021769 (deposited in C that was the basis for the respective plate. We select this specimen as the lectotype of Blechnum spicant var. fallax.

  12. 4-D-Var or ensemble Kalman filter?

    OpenAIRE

    Kalnay, Eugenia; LI, HONG; Miyoshi, Takemasa; Yang, Shu-Chih; Ballabrera-Poy, Joaquim

    2007-01-01

    We consider the relative advantages of two advanced data assimilation systems, 4-D-Var and ensemble Kalman filter (EnKF), currently in use or under consideration for operational implementation. With the Lorenz model, we explore the impact of tuning assimilation parameters such as the assimilation window length and background error covariance in 4-D-Var, variance inflation in EnKF, and the effect of model errors and reduced observation coverage. For short assimilation windows EnKF gives more a...

  13. ROM Simulation: Applications to Stress Testing and VaR

    OpenAIRE

    Carol Alexander; Daniel Ledermann

    2012-01-01

    Most banks employ historical simulation for Value-at-Risk (VaR) calculations, where VaR is computed from a lower quantile of a forecast distribution for the portfolio’s profit and loss (P&L) that is constructed from a single, multivariate historical sample on the portfolio’s risk factors. The implicit assumption is that history will repeat itself for certain over the forecast horizon. Until now, the only alternative is to assume the historical sample is generated by a multivariate, parametric...

  14. Oil price fluctuations and their impact on the macroeconomic variables of Kuwait: a case study using a VAR model

    Energy Technology Data Exchange (ETDEWEB)

    Eltony, M. Nagy; Al-Awadi, Mohammad [Arab Planning Inst., Safat (Kuwait)

    2001-09-01

    In this study, a vector autoregression model (VAR) and a vector error correction model (VECM) were estimated to examine the impact of oil price fluctuations on seven key macroeconomic variables for the Kuwaiti economy. Quarterly data for the period 1984-1998 were utilised. Theoretically and empirically speaking, VECM is superior to the VAR approach. Also, the results corresponding to the VECM model are closer to common sense. However, the estimated models indicate a high degree of interrelation between major macroeconomic variables. The empirical results highlight the causality running from the oil prices and oil revenues, to government development and current expenditure and then towards other variables. For the most part, the empirical evidence indicates that oil price shocks and hence oil revenues have a notable impact on government expenditure, both development and current. However, government development expenditure has been influenced relatively more. The results also point out the significant of the CPI in explaining a notable part of the variations of both types of government expenditure. On the other hand, the variations in value of imports are mostly accounted for by oil revenue fluctuations. On the other hand, the variations in value of imports are mostly accounted for by oil revenue fluctuations and then by the fluctuation in government development expenditures. Also, the results from the VECM approach indicate that a significant part of LM2 variance is explained by the variance in oil revenue. It reaches about 46 per cent in the 10th quarter, even more than its own variations. (Author)

  15. Altitudinal Variation in Aboveground Biomass of Abies georgei var.smithii at Timberline of the Sergyemla Mountains, Southeast Tibet%藏东南色季拉山急尖长苞冷杉林线地带地上生物量随海拔的变化特征

    Institute of Scientific and Technical Information of China (English)

    刘新圣; 张林; 孔高强; 罗天祥

    2011-01-01

    Environment becomes harsh with increasing altitude, which has major effects on forest biomass accumulation and its allocation to woody and foliage components.In this study, we compared aboveground biomass and its allocation pattern of Abies georgei[var.smithii along a transect from sub-alpine forest to alpine timberline in the Sergyemla Mountain, southeast Tibet.We estimated different components of aboveground biomass for Abies trees and undergrowth Rhododendron shrubs by using allometric regressions.The aboveground biomass of undergrowth herbs was measured by harvesting in 0.5 m ×0.5 m quadrats.Aboveground biomasses were 181 ~284 t/hm2, 117 ~ 248 t/hm2, 35 ~ 62 t/hm2 and 0.9 ~ 1.5 t/hm2 for whole community, trees, undergrowth shrubs and herbs, respectively.Aboveground biomass of the whole community decreased significantly with increasing elevation, and the decreasing rate was 73.1 t/hm2 per 100 m.Furthermore, the Abies forest stand at higher elevation tended to reduce biomass allocation to non-photosynthesis organs (stem and branch), and to increase the allocation to longlived needles.The increased biomass allocation to long-lived needles at higher elevations may extend the mean residence time of nutrients in plants, and then enhance nutrient use efficiency of dry mass production to adapt to the low temperature environment at alpine timberlines.%从亚高山森林到高山林线,逐渐严酷的生长环境影响了生物量的积累和分配.本研究采用相对生长法和样方收获法估算了藏东南色季拉山急尖长苞冷杉林在禾同海拔(4 190 m,4 270 m和4 326 m)的地上生物量,分析了群落中不同层次地上生物量、各器官生物量及其分配比例随海拔的变化格局.结果表明:1.急尖长苞冷杉群落地上生物量在181~284 t/hm2之间,其中,乔木层在11~-248 t/hm2,灌木层为35~62 t/hm2,草本层为0.9~1.5 t/hm2;2.群落地上生物量随海拔升高急剧降低,降低的平均幅度为73.1 t/(hm2

  16. An historical analysis of the California Current circulation using ROMS 4D-Var: System configuration and diagnostics

    Science.gov (United States)

    Neveu, Emilie; Moore, Andrew M.; Edwards, Christopher A.; Fiechter, Jérôme; Drake, Patrick; Crawford, William J.; Jacox, Michael G.; Nuss, Emma

    2016-03-01

    The Regional Ocean Modeling System (ROMS) 4-dimensional variational (4D-Var) data assimilation tool has been used to compute two sequences of circulation analyses for the U.S. west coast. One sequence of analyses spans the period 1980-2010 and is subject to surface forcing derived from relatively low resolution atmospheric products from the Cross-Calibrated Multi-Platform wind product (CCMP) and the European Centre for Medium Range Weather Forecasts (ECMWF) reanalysis project. The second sequence spans the shorter period 1999-2012 and is subject to forcing derived from a high resolution product from the Naval Research Laboratory Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS). The two analysis periods are divided into eight day windows, and all available satellite observations of sea surface temperature and sea surface height, as well as in situhydrographic profiles are assimilated into ROMS using 4D-Var. The performance of the system is monitored in terms of the cost function and the statistics of the innovations, and the impact of data assimilated on the circulation is assessed by comparing the posterior circulation estimates with the prior circulation and the circulation from a run of the model without data assimilation, with particular emphasis on eddy kinetic energy. This is part I of a two part series, and the circulation variability of the 4D-Var analyses will be documented in part II.

  17. Estimativa de parâmetros genéticos e ganhos na seleção para caracteres de crescimento em teste de progênies de Pinus caribaea var. hondurensis e var. bahamensis, em Assis-SP. Estimates of genetic parameters and gains from selection for growth traits in Pinus caribaea var. hondurensis and var. bahamensis progeny tests, in Assis-SP.

    Directory of Open Access Journals (Sweden)

    Alexandre Magno SEBBENN

    2010-12-01

    Full Text Available Os objetivos deste estudo foram estimar parâmetros genéticos e ganhos na seleção em diâmetro à altura do peito – DAP e altura em um teste de 14 progênies de polinização aberta de P. caribaea var. hondurensis e seis de P. caribaea var. bahamensis, aos 13 anos de idade, estabelecido em Assis, SP. Para fins de comparação, uma testemunha P. caribaea var. hondurensis foi incluída no ensaio. O delineamento experimental utilizado foi o látice retangular 4 x 5, com parcelas de dez plantas no espaçamento de 3 m x 3 m, totalizando 20 tratamentos com três repetições. Não foram detectadas diferenças entre as variedades. Variações significativas entre progênies de ambas asvariedades foram detectadas em altura. As médias das progênies de ambas as variedades foram maiores que a média da testemunha, indicando que o material testado tem potencial para ser utilizado em reflorestamentos na região de Assis. A variação genética e os coeficientes de herdabilidades foram maiores em DAP do que em altura, indicando que maiores ganhos podem ser obtidos mediante seleção em DAP. Os ganhos genéticos preditos em plantios com 13 anos de idade, em locais com características ambientais semelhantes às de Assis e realizados com sementes coletadas após a seleção no teste de progênies de Pinus caribaea var. bahamensis foi estimado para o DAP em 6,36%.The aims of this study were to estimate genetic parameters and gains from selection for diameter at breast height – DBH and height in 14 open-pollinated progenies of P. caribaea var. hondurensis and six of P. caribaea var. bahamensis, at 13 years of age, established in Assis, State of São Paulo. A control treatment with the same var. bahamensis was included in the trial. The trial was analyzed as a 4 x 5 rectangular lattice, with 21 treatments, three replications and 10 plants per plot. No significant differences were found between varieties. A significant variation among progenies within

  18. 河南地区HIV-1毒株Gag基因抗原表位变异特征及准种特点研究%Study of Gag gene antigen epitypes variation and the quasispecies group characteristics in Henan area HIV-1 strains

    Institute of Scientific and Technical Information of China (English)

    杜鹏; 陈国敏; 李泽琳; 曾毅

    2009-01-01

    Objective To study the characteristics of the variation of antigen epitopes and quasispecies group in the HIV-1 viruses in Henan province in China. Methods The region of the p17-p24 of the HIV-1 gag gene was amplified by nested polymerse chain resction(PCR), purified products were cloned into the vector, the obtained were analyzed by MEGA soft wares. Results B' subtype strains were predominant in Henan province, the mutations in antigen epitypes of the p17 region of the gag gene focus on E62g(55.8% ) ,Y79f(48.9% ) ,T84V (48.9), I44V(44.2%), the p24 region had not found the distinct mutation. Conclusion Both the PCR sequences and clone strains sequences demonstrated that four antigen epitopes mutations in p17 region of the HIV B' subtype gag gene, and the region of p24 was more conservative,which was suitable for development of the epitope vaccien.%目的 探讨中国河南地区人免疫缺陷病毒Ⅰ型(HIV-1)毒株GAG蛋白抗原表位变异特征,并对其准种特点加以分析.方法 套式聚合酶链反应(Nested-PCR)扩增确认HIV阳性样本gagp17~p24基因区段并测序,PCR产物纯化后克隆,挑选克隆株鉴定为阳性后测序,以MEGA(version 3.0)等软件进行分析.结果 河南HIV毒株为B'亚型;gag基因p17区段抗原表位突变有E62G(55.80%),Y79F(48.90%),T84V(48.90%),144V(44.20%),gag基因p24区段抗原表位未见明显变异.结论 HIV-1 B'亚型毒株gag基因p17区段的4个抗原表位,存在较大变异,p24区段较为保守,适合抗原表位疫苗的研制.

  19. Isolation and characterization of human rhinovirus antigenic variants

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D.G.

    1985-01-01

    Isolation of antigenic variants of human rhinovirus types 2, 14, and 17 was attempted by plaquing untreated virus (P-isolates), selecting variants in the presence of homologous antiserum (C-isolates), and by selecting variants in the presence of antibody following 5-fluorouracil mutagenesis (M-isolates). All viruses were triple-plaque purified and purity neutralization tested prior to isolate selection. Based on a fourfold reduction in neutralizing antibody titer to homologous antiserum, no antigenic variation was found in P-isolates from the three serotypes examined. Antigenic variants of all three serotypes could be isolated by the antiserum selection method (C-isolates). However, antigenic variants of RV17 were isolated at a much higher frequency and showed a larger degree of variation than those of RV2 and RV14. At least two of the variants selected, RV17 (C301) and RV2 (M803), failed to be neutralized by the known 89 rhinovirus antiserum. SDS-polyacrylamide gel electrophoresis of (/sup 35/S) methionine-labelled virion polypeptides revealed that each serotype had a characteristic pattern and that selected RV2 and RV17 isolates had patterns identical to those of the prototype strains. By isoelectric focusing an antigenic variant of RV2 was shown to contain altered virion polypeptides VP1 and VP2 whereas two RV17 antigenic variants demonstrated alterations only in the VP1 polypeptide.

  20. Estudo micrometeorológico com cenouras (var. nantes I- Influência da temperatura do ar Micrometebeologic study with carrots (var. nantes. I- Influence of air temperature

    Directory of Open Access Journals (Sweden)

    Orivaldo Brunini

    1976-01-01

    Full Text Available Analisou-se o efeito da temperatura do ar sobre o desenvolvimento de cenouras (var. Nantes, cultivadas em latossolo roxo sob quatro condições: com cobertura de plástico sobre a cultura em solo nu; sem cobertura de plástico sobre a cultura e solo com cobertura morta; com cobertura de plástico sobre a cultura e solo com cobertura morta; e sem cobertura de plástico sobre a cultura e solo nu. O tratamento com cobertura de plástico e solo eom cobertura morta foi o que apresentou maior produtividade, além de diminuir o ciclo da cultura. As variações térmicas mostraram-se correlacionadas com o tipo de cobertura a que esteve sujeita a cultura, sendo que o tratamento com cobertura de plástico e solo com cobertura morta apresentou maiores valores da temperatura do ar, e o tratamento sem cobertura conservando o solo nu apresentou menores valores da temperatura do ar.The effect of air temperature on the development of carrots (var. nantes was analysed under four conditions: with polyethylene cover over the crops, and bare soil: without polyethylene cover over the crop, and soil with mulch; with polyethylene cover over the crops, and mulch; and without polyethylene cover over the crop, and bare soil. The treatment with polyethylene cover over the crop and soil with mulch increased the yields and shortened the maturity date. The thermal variations of air were correlated with the type of mulch, and the yields were correlated with air temperature too.

  1. A New Cyclohexene Oxide from Uvaria tonkinensis var. subglabra

    Institute of Scientific and Technical Information of China (English)

    An LIU; Zhong Mei ZOU; Li Zhen XU; Shi Lin YANG

    2003-01-01

    A new compound, subglain B, was isolated from the stems of Uvaria tonkinensis var. subglabra and its structure was identified as 1S, 2R, 3S, 6R-1-benzoyloxymethylene-1,2- dihydroxy-3-benzoyloxy-6-chlorocyclohex-4-ene (1), by spectral evidences.

  2. Indolizidine, Antiinfective and Antiparasitic Compounds from Prosopis glandulosa var. glandulosa

    Science.gov (United States)

    Prosopilosidine, a new potent antiinfective and antiparasitic 2,3-dihydro-1H-indolizinium chloride, (1), was isolated from Prosopis glandulosa Torr. var. glandulosa. Furthermore, three additional new and one known indolizidines, prosopilosine (2), isoprosopilosine (3), isoprosopilosidine (4) and jul...

  3. A Bootstrap Cointegration Rank Test for Panels of VAR Models

    DEFF Research Database (Denmark)

    Callot, Laurent

    functions of the individual Cointegrated VARs (CVAR) models. A bootstrap based procedure is used to compute empirical distributions of the trace test statistics for these individual models. From these empirical distributions two panel trace test statistics are constructed. The satisfying small sample...

  4. New diterpenes from the heartwood of Chamaecyparis obtusa var. formosana.

    Science.gov (United States)

    Kuo, Y H; Chen, C H; Huang, S L

    1998-06-26

    An abietane diterpene, 11,14-dihydroxy-8,11,13-abietatrien-7-one (1); a seco-abietane diterpene, obtuanhydride (2); and an isopimarane diterpene, 18,19-O-isopropylidene-18, 19-dihydroxyisopimara-8(14),15-diene (3) were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these new compounds were elucidated by spectroscopic methods.

  5. Two New Abietane Quinones from Isodon lophanthoides var. Micranthus

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The structures of two new abietane quinones, named micranthins A and B, weredetermined to be 7α-methoxy-14, 16-epoxy-8, 13-abietadiene-11, 12-dione (1) and 16-acetoxy-6,7-dehydroroyleanone (2) respectively, which were isolated from Isodon lophanthoides var.micranthus.

  6. Data Assimilation of Lightning using 1D+3D/4D WRF Var Assimilation Schemes with Non-Linear Observation Operators

    Science.gov (United States)

    Navon, M. I.; Stefanescu, R.; Fuelberg, H. E.; Marchand, M.

    2012-12-01

    NASA's launch of the GOES-R Lightning Mapper (GLM) in 2015 will provide continuous, full disc, high resolution total lightning (IC + CG) data. The data will be available at a horizontal resolution of approximately 9 km. Compared to other types of data, the assimilation of lightning data into operational numerical models has received relatively little attention. Previous efforts of lightning assimilation mostly have employed nudging. This paper will describe the implementation of 1D+3D/4D Var assimilation schemes of existing ground-based WTLN (Worldwide Total Lightning Network) lightning observations using non-linear observation operators in the incremental WRFDA system. To mimic the expected output of GLM, the WTLN data were used to generate lightning super-observations characterized by flash rates/81 km2/20 min. A major difficulty associated with variational approaches is the complexity of the observation operator that defines the model equivalent of lightning. We use Convective Available Potential Energy (CAPE) as a proxy between lightning data and model variables. This operator is highly nonlinear. Marecal and Mahfouf (2003) have shown that nonlinearities can prevent direct assimilation of rainfall rates in the ECMWF 4D-VAR (using the incremental formulation proposed by Courtier et al. (1994)) from being successful. Using data from the 2011 Tuscaloosa, AL tornado outbreak, we have proved that the direct assimilation of lightning data into the WRF 3D/4D - Var systems is limited due to this incremental approach. Severe threshold limits must be imposed on the innovation vectors to obtain an improved analysis. We have implemented 1D+3D/4D Var schemes to assimilate lightning observations into the WRF model. Their use avoids innovation vector constrains from preventing the inclusion of a greater number of lightning observations Their use also minimizes the problem that nonlinearities in the moist convective scheme can introduce discontinuities in the cost function

  7. The Prevalence of Hepatitis B Virus Surface Antigen (HBsAg Variations and Correlation with the Clinical and Serologic Pictures in Chronic Carriers from Khorasan Province, North-East of Iran

    Directory of Open Access Journals (Sweden)

    Alireza Namazi

    2012-04-01

    Full Text Available This study was designed to determine the correlation of hepatitis B virus surface Ag (HBsAg variations with the clinical/serological pictures among chronic HBsAg positive patients. The surface gene (S-gene was amplified and directly sequenced in twenty-five patients. Eight samples (group I contained at least one mutation at the amino acid level. Five showed alanine aminotransferase (ALT levels above the normal range of which only one sample was anti-HBe positive. Group II (17 samples did not contain any mutation, 4 were anti-HBe positive and 9 had increased ALT levels. In both groups, from a total of 18 mutations, 5 (27.5% and 13 (72.5% occurred in anti-HBe and HBeAg positive groups respectively. The small number of amino acid mutations might belong to either the initial phase of chronicity in our patients; or that even in anti-HBe positive phase in Iranian genotype D-infected patients, a somehow tolerant pattern due to the host genetic factors may be responsible.

  8. [Genetic diversity and mating system Pinus brutia var. Stankewiczii sukacz. in small localities of Sudak (Crimea)].

    Science.gov (United States)

    Korshikov, I I; Kalafat, L A; Milchevskaya, Ya G

    2015-01-01

    A comparative analysis of genetic variation at 12 polymorphic isozyme loci, and the mating system has been carried out in mature trees and their seed progeny in three small localities of Pinus brutia var. stankewiczii Sukacz. near the town of Sudak--settlement of Novyi Svet in the Crimea. We found that embryos maintain the same allelic diversity as mother plants but their observed heterozygosity is lower on the average by 37.4%. The significant deviation of genotype distribution from the theoretically expected ratios caused by the deficiency of heterozygotes was observed at 8 out of 12 loci. Multilocus estimate of outcrossing rate (t(m)) in populations varied from 68.9 to 94.9% making on the average 80.7%.

  9. Human pregnancy-associated malaria-specific B cells target polymorphic, conformational epitopes in VAR2CSA

    DEFF Research Database (Denmark)

    Barfod, L.; Bernasconi, N. L.; Dahlback, M.

    2007-01-01

    , are targets of IgG-mediated protective immunity to PAM. Here, we report an investigation of the specificity of naturally acquired immunity to PAM, using eight human monoclonal IgG1 antibodies that react exclusively with intact CSA-adhering IEs expressing VSA(PAM). Four reacted in Western blotting with high......-specific protective immunity, and demonstrate the value of human monoclonal antibodies and conformationally intact recombinant antigens in VSA characterization....... to evaluate B-cell epitope diversity among parasite isolates, and identified the binding site of one monoclonal antibody using a chimeric DBL3-X construct. Our findings show that there is a high-frequency memory response to VSA(PAM), indicating that VAR2CSA is a primary target of naturally acquired PAM...

  10. Structural Studies on Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) Malaria Antigens Using Small Angle X-Ray Scattering (SAXS)

    DEFF Research Database (Denmark)

    Christoffersen, Stig

    against placental malaria, VAR2CSA was studied extensively. By the use of SAXS on multiple truncated VAR2CSA constructs it was possible to combine the acquired information and present a structural model for the DBL and CIDR domain arrangement in VAR2CSA. This work was published in Journal of Biological...... symptoms and vaccine research is focused on trying to mimic or advance this immune acquisition. Immunity is primarily caused by acquisition of antibodies directed against a family of Plasmodium protein antigens called PfEMP1s located on the surface of infected erythrocytes. The PfEMP1 proteins are adhesive...... knowledge for these proteins is required. During the time course of this PhD thesis I have studied a number of PfEMP1 proteins using the SAXS technique. This biophysical technique has gained widespread attention during the past decade due to scientific and computational developments. SAXS is X...

  11. EFEITO FUNGITÓXICO DO ÓLEO DE NIM SOBRE Metarhizium anisopliae var. acridum e Metarhizium anisopliae var. anisopliae

    Directory of Open Access Journals (Sweden)

    Álison Bruno da Silva Santos

    2009-01-01

    Full Text Available Plague control is based almost exclusively on application of chemical substances, however these products are toxic to men and animals and cause odd effects on environment quality. In Plague Integrated Management (PIM, the use of selected insecticides and entomopathogenic fungi should be considered as one viable strategy for plague control in agriculture. This work aimed to evaluate, in laboratory, the compatibility of the entomopathogenic fungi Metarhizium anisopliae var. acridum and Metarhizium anisopliae var. anisopliae with the oil of Nim. The addition of the product was made to the potato-dextrose-agar medium still liquid (±45°C, in a way that the final concentration obeyed 50% of the producer's recommendation. After fungi inoculation, the dishes were incubated in a cimatized room at 28°C, photophase of 12 hours and relative humidity of 75±5% for 12 day period. The number of conidia per colonie was counted with a Neubauer chamber. Statistic delineament was entirely in random, with two treatments (PDA with insecticide, and a control group (PDA without insecticide, and 9 repetitions for each treatment. The results showed that the insecticide inhibited conidial production in Metarhizium anisopliae var. anisopliae strains when compared to the control group. The diameter of Metarhizium anisopliae var. acridum colonies suffered significative reduction in its size, compared to control. The tested insecticide, in the concentration and formulation used, presented compatibility with the tested strains.

  12. Cancer testis antigen and immunotherapy

    Directory of Open Access Journals (Sweden)

    Krishnadas DK

    2013-04-01

    Full Text Available Deepa Kolaseri Krishnadas, Fanqi Bai, Kenneth G Lucas Department of Pediatrics, Division of Hematology/Oncology, University of Louisville, KY, USA Abstract: The identification of cancer testis (CT antigens has been an important advance in determining potential targets for cancer immunotherapy. Multiple previous studies have shown that CT antigen vaccines, using both peptides and dendritic cell vaccines, can elicit clinical and immunologic responses in several different tumors. This review details the expression of melanoma antigen family A, 1 (MAGE-A1, melanoma antigen family A, 3 (MAGE-A3, and New York esophageal squamous cell carcinoma-1 (NY-ESO-1 in various malignancies, and presents our current understanding of CT antigen based immunotherapy. Keywords: cancer testis antigens, immunotherapy, vaccine

  13. Identification and characterization of a LTR retrotransposon from the genome of Cyprinus carpio var. Jian.

    Science.gov (United States)

    Cao, Liping; Yin, Guojun; Cao, Zheming; Bing, Xuwen; Ding, Weidong

    2016-06-01

    A Ty3/gypsy-retrotransposon-type transposon was found in the genome of the Jian carp (Cyprinus carpio var. Jian) in a previous study (unpublished), and was designated a JRE retrotransposon (Jian retrotransposon). The full-length JRE retrotransposon is 5126 bp, which includes two long terminal repeats of 470 bp at the 5' end and 453 bp at the 3' end, and two open reading frames between them: 4203 bp encoding the group-specific antigen (GAG) and polyprotein (POL). The pol gene has a typical Ty3/gypsy retrotransposon structure, and the gene order is protease, reverse transcriptase, RNase H, and integrase (PR-RT-RH-IN). A phylogenetic analysis of the pol gene showed that it has similarities of 40.7, 40, and 32.8 %, to retrotransposons of Azumapecten farreri, Mizuhopecten yessoensis, and Xiphophorus maculatus, respectively. Therefore, JRE might belong to the JULE retrotransposon family. The copy number of the JRE transposon in the genome of the Jian carp is 124, determined with real-time quantitative PCR. The mRNA of the JRE retrotransposon is expressed in five Jian carp tissues, the liver, kidney, blood, muscle, and gonad, and slightly higher in the kidney and liver than in the other tissues.

  14. Characterization of O-antigen delivered by Generalized Modules for Membrane Antigens (GMMA) vaccine candidates against nontyphoidal Salmonella.

    Science.gov (United States)

    De Benedetto, G; Alfini, R; Cescutti, P; Caboni, M; Lanzilao, L; Necchi, F; Saul, A; MacLennan, C A; Rondini, S; Micoli, F

    2017-01-11

    Invasive nontyphoidal Salmonella disease (iNTS) is a leading cause of death and morbidity in Africa. The most common pathogens are Salmonella enterica serovars Typhimurium and Enteritidis. The O-antigen portion of their lipopolysaccharide is a target of protective immunity and vaccines targeting O-antigen are currently in development. Here we investigate the use of Generalized Modules for Membrane Antigens (GMMA) as delivery system for S. Typhimurium and S. Enteritidis O-antigen. Gram-negative bacteria naturally shed outer membrane in a blebbing process. By deletion of the tolR gene, the level of shedding was greatly enhanced. Further genetic modifications were introduced into the GMMA-producing strains in order to reduce reactogenicity, by detoxifying the lipid A moiety of lipopolysaccharide. We found that genetic mutations can impact on expression of O-antigen chains. All S. Enteritidis GMMA characterized had an O-antigen to protein w/w ratio higher than 0.6, while the ratio was 0.7 for S. Typhimurium ΔtolR GMMA, but decreased to less than 0.1 when further mutations for lipid A detoxification were introduced. Changes were also observed in O-antigen chain length and level and/or position of O-acetylation. When tested in mice, the GMMA induced high levels of anti-O-antigen-specific IgG functional antibodies, despite variation in density and O-antigen structural modifications. In conclusion, simplicity of manufacturing process and low costs of production, coupled with encouraging immunogenicity data, make GMMA an attractive strategy to further investigate for the development of a vaccine against iNTS.

  15. Antigen antibody interactions

    CERN Document Server

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  16. Trypanosoma cruzi: circulating antigens

    Directory of Open Access Journals (Sweden)

    V. Bongertz

    1981-03-01

    Full Text Available Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice. The immunodiffusion reaction between homologous acute and chronic sera produced four precipitation lines. By reaction with chronic mouse serum, circulating antingens were detected in sera from heavily infected hamsters, dogs, rabbits and in sera from chagasic patients. A reaction was also found in urine from acutely infected mice and dogs. Trypanosoma cruzi exoantigen was detected in trypanosome culture medium and in the supernatant of infected cell cultures. Attempts to isolate the antigens are described.Antígenos circulantes foram detectados em soros de camundongos infectados experimentalmente com elevadas doses de Trypanosoma cruzi pela reação com soros obtidos de camundongos em fase crônica de infecção. A reação de imunodifusão entre soros homólogos agudo e crônico produziu quatro linhas de precipitação. Por reação com soro crônico de camundongo antígenos circulantes foram detectados em soros de crícetos, cães e coelhos infectados com doses elevadas de Trypanosoma cruzi e em soros de pacientes chagásicos. Uma reação foi também observada com urina de camundongos e cães infectados de forma aguda. Exoantígeno de Trypanosoma cruzi foi detectado em meio de cultura de tripanosomas e em sobrenadantes de culturas de células infectadas. Tentativas de isolamento dos antigenos são descritas.

  17. [Physiological characteristics of Pinus densiflora var. zhangwuensis and Pinus sylvestris var. mongolica seedlings on sandy lands under salt-alkali stresses].

    Science.gov (United States)

    Meng, Peng; Li, Yu-Ling; Zhang, Bai-xi

    2013-02-01

    For the popularization of Pinus densiflora var. zhangwuensis, a new afforestation tree species on the desertified and salinized-alkalized lands in Northern China, and to evaluate the salinity-alkalinity tolerance of the tree species and to better understand the tolerance mechanisms, a pot experiment with 4-year old P. densiflora var. zhangwuensis and P. sylvestris var. mongolica was conducted to study their seedlings growth and physiological and biochemical indices under the effects of three types salt (NaCl, Na2CO3, and NaHCO3 ) stresses and of alkali (NaOH) stress. Under the salt-alkali stresses, the injury level of P. densiflora var. zhangwuensis was lower, and the root tolerance index was higher. The leaf catalase (CAT) activity increased significantly by 22. 6 times at the most, as compared with the control; the leaf malondialdehyde (MDA) content had no significant increase; the leaf chlorophyll (Chl) content had a smaller decrement; and the leaf water content (LWC) increased slightly. P. sylvestris var. mongolica responded differently to the salt-alkali stresses. Its leaf CAT activity had less change, MDA content increased significantly, Chl content had significant decrease, and LWC decreased slightly. It was suggested that P. densi-flora var. zhangwuensis had a greater salinity-alkalinity tolerance than P. sylvestris var. mongolica. The higher iron concentration in P. densiflora var. zhangwuensis needles enhanced the CAT activity and Chl content, whereas the higher concentrations of zinc and copper were associated with the stronger salinity-alkalinity tolerance.

  18. [Photosynthetic parameters and physiological indexes of Paris polyphylla var. yunnanensis influenced by arbuscular mycorrhizal fungi].

    Science.gov (United States)

    Wei, Zheng-xin; Guo, Dong-qin; Li, Hai-feng; Ding, Bo; Zhang, Jie; Zhou, Nong; Yu, Jie

    2015-10-01

    Through potted inoculation test at room temperature and indoor analysis, the photosynthetic parameters and physiological and biochemical indexes of Paris polyphylla var. yunnanensis were observed after 28 arbuscular mycorrhizal (AM) fungi were injected into the P. polyphylla var. yunnanensis growing in a sterile soil environment. The results showed that AM fungi established a good symbiosis with P. polyphylla var. yunnanensis. The AM fungi influenced the photosynthetic parameters and physiological and biochemical indexes of P. polyphylla var. yunnanensis. And the influences were varied depending on different AM fungi. The application of AM fungi improved photosynthesis intensity of P. polyphylla var. yunnanensis mesophyll cells, the contents of soluble protein and soluble sugar, protective enzyme activity of P. polyphylla var. yunnanensis leaf, which was beneficial to resist the adverse environment and promote the growth of P. polyphylla var. yunnanensis. Otherwise, there was a certain mutual selectivity between P. polyphylla var. yunnanensis and AM fungi. From the comprehensive effect of inoculation, Racocetra coralloidea, Scutellospora calospora, Claroideoglomus claroideum, S. pellucida and Rhizophagus clarus were the most suitable AM fungi to P. polyphylla var. yunnanensis when P. polyphylla var. yunnanensis was planted in the field.

  19. Introduction & Grafting Test for Pinus sylvestris var. fastigiata (Carr.) Q. F. Anet in Qiqihar Area%齐齐哈尔地区钻天松引种与嫁接繁殖试验

    Institute of Scientific and Technical Information of China (English)

    郑兴伟; 郑兴秋; 赵凌泉; 史绍林

    2012-01-01

    Compared with climatic conditions between Qiqihar region and provenance, Pinus sylvestris var. fastigiata ( Carr. ) were introduced. According to characteristics ( a large progeny variation in the seed production) of Pinus sylvestris var. fastigiata (carr) ,grafting experiments were conducted by using Pinus sylvestris var. mongolica as stock. Result shows that introduction of Pinus sylvestris var. fastigiata (carr) Q. F. Anet is possible. In order to cultivate large seedlings of Pi- nus sylvestris var. fastigiata( carr ) Q. F. Anet, three-year-old Pinus sylvestris var. mongolica were used as stock;softwood of one-year-old Pinus sylvestris var. fastigiata Q. F. Anet were grafted;the mean grafting ratio are 73.5%.%在齐齐哈尔地区与种源地气候条件比较基础上,进行了钻天松的引种,并针对其种子繁殖后代变异较大的特点,开展了用樟子松作砧木进行嫁接繁殖试验,试验结果表明,在齐齐哈尔地区引种钻天松是可行的。为了尽快培育大量的钻天松苗木,可以用樟子松3年生容器苗作砧木,采集1年生钻天松嫩枝进行嫁接,平均嫁接成活率为73.5%。

  20. VaR: Exchange Rate Risk and Jump Risk

    Directory of Open Access Journals (Sweden)

    Fen-Ying Chen

    2010-01-01

    Full Text Available Incorporating the Poisson jumps and exchange rate risk, this paper provides an analytical VaR to manage market risk of international portfolios over the subprime mortgage crisis. There are some properties in the model. First, different from past studies in portfolios valued only in one currency, this model considers portfolios not only with jumps but also with exchange rate risk, that is vital for investors in highly integrated global financial markets. Second, in general, the analytical VaR solution is more accurate than historical simulations in terms of backtesting and Christoffersen's independence test (1998 for small portfolios and large portfolios. In other words, the proposed model is reliable not only for a portfolio on specific stocks but also for a large portfolio. Third, the model can be regarded as the extension of that of Kupiec (1999 and Chen and Liao (2009.

  1. MANAGEMENT OF Amburana cearensis var. acreana IN ACRE STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Evaldo Muñoz Braz

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814586This work has as its objectives: a to assess the geographical distribution and population structure of Amburana cearensis var. acreana; b to calculate sustainable cutting rates, according to stipulated cutting cycles, and c to simulate the projected recovery potential in volume based on the calculated cutting rate. It was used data from sustainable forest management plans, and the results will contribute for future decisions about its endangered condition. The results did not corroborate the information that Amburana cearensis var. acreana is endangered in Acre state. However the management sustainability will only be feasible if considered the ideal remaining population structure and the estimative of the optimal cutting rate according to the cutting cycle.

  2. [Glycosides from flowers of Jasminum officinale L. var. grandiflorum].

    Science.gov (United States)

    Zhao, Gui-qin; Xia, Jing-jing; Dong, Jun-xing

    2007-10-01

    To study the chemical constituents of the flower of Jasminum officinale L. var. grandiflorum. The compounds were isolated and purified by re-crystallization and chromatography on silica gel and Sephadex LH-20 column. Their structures were elucidated on the physicochemical properties and spectral analysis. Seven glycosides were identified as kaempferol-3-O-alpha-L-rhamnopyranosyl (1-->3)-[alpha-L-rhamnopyranosyl (1-->6)]-beta-D-galactopyranoside (I), kaempferol-3-O-rutinoside (II), 7-ketologanin (III), oleoside-11-methyl ester (IV), 7-glucosyl-l1-methyl oleoside (V), ligstroside (VI), oleuropein (VII). Compound I is a new compound. Compounds III and V were isolated from the family of Jasminum for the first time and compounds II, IV and VI were isolated from Jasminum officinale L. var. grandiflorum for the first time.

  3. Static Var Compensator Project for the SPS Electrical Network

    CERN Document Server

    Kahle, K

    2000-01-01

    This paper gives a progress report on the Static Var Compensator project BEF2 for the SPS electrical network. Following a market survey and a call for tenders, a contract has been awarded to ABB Sweden and the project is now in the phase of detailed performance studies, system design and ordering of the main electrical components. This progress report describes the electrical design, summarises the results of the harmonic filter design studies, discusses the interfacing of the control- and communication system and explains the mechanical layout of the Static Var Compensator and as well as the project co-ordination with the feeding BE substation renovation project. Finally, the project planning is presented and critical paths are evaluated.

  4. Inflows and their Macroeconomic Impact in India a VAR Analysis

    Directory of Open Access Journals (Sweden)

    Narayan Sethi

    2012-12-01

    Full Text Available The present study attempts to examine the effects of private foreign capital inflows (FINV on macroeconomic variables in India. The study also examines the trends and composition of capital inflows into India. Using the Vector Autoregression (VAR method, this paper specifically examines effects of private foreign capital inflows (FINV on macroeconomic variables in India. This study is based on the monthly data from 1995:04 to 2011:07 and incorporating the macroeconomic variables such as exchange rate (EXR, inflation, money supply (M3, export (EXPO, import (IMP, foreign exchange reserve (FOREX and economic growth (IIP as proxy of GDP. The important observations emerge from the VAR analysis which shows there is dynamic short and long equilibrium relationship between few macroeconomic variables like exchange rate (EXR, foreign exchange reserve (FOREX, index of industrial production (IIP and money supply (M3 with private foreign capital inflows (FINV during the study period from 1995:04 to 2011:07

  5. The complete chloroplast genome sequence of Dianthus superbus var. longicalycinus.

    Science.gov (United States)

    Gurusamy, Raman; Lee, Do-Hyung; Park, SeonJoo

    2016-05-01

    The complete chloroplast genome (cpDNA) sequence of Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicine was reported and characterized. The cpDNA of Dianthus superbus var. longicalycinus is 149,539 bp, with 36.3% GC content. A pair of inverted repeats (IRs) of 24,803 bp is separated by a large single-copy region (LSC, 82,805 bp) and a small single-copy region (SSC, 17,128 bp). It encodes 85 protein-coding genes, 36 tRNA genes and 8 rRNA genes. Of 129 individual genes, 13 genes encoded one intron and three genes have two introns.

  6. Tumor markers cancer antigen 15.3, carcinoembryonic antigen, and tissue polypeptide antigen for monitoring metastatic breast cancer during first-line chemotherapy and follow-up

    DEFF Research Database (Denmark)

    Sölétormos, G; Nielsen, D; Schiøler, V;

    1996-01-01

    follow-up. Each sample was analyzed for cancer antigen 15.3, carcinoembryonic antigen, and tissue polypeptide antigen. The efficiency for identifying progression and nonprogression was 94% during therapy and 85% during follow-up, with no false-positive marker results for progressive disease. At clinical......We investigated whether model systems integrating stochastic variation into criteria for marker assessment could be used for monitoring metastatic breast cancer. A total of 3989 serum samples was obtained from 204 patients receiving first-line chemotherapy and from 112 of these patients during...... progressive disease, the median positive lead time was 35 days during therapy and 76 days during follow-up. Tumor marker assessment may document that a therapy is effective and ought to be continued in spite of adverse toxic effects, and that a treatment is ineffective and should be stopped to prevent...

  7. Radioimmunoassays of hidden viral antigens

    Energy Technology Data Exchange (ETDEWEB)

    Neurath, A.R. (Lindsley F. Kimbell Research Inst., New York, NY); Strick, N.; Baker, L.; Krugman, S.

    1982-07-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid-phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bound adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure.

  8. Radioimmunoassays of hidden viral antigens.

    Science.gov (United States)

    Neurath, A R; Strick, N; Baker, L; Krugman, S

    1982-01-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bond adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure. Images PMID:6956871

  9. Identification of Phytophthora fragariae var. rubi by PCR.

    Science.gov (United States)

    Schlenzig, Alexandra

    2009-01-01

    The following chapter describes a PCR method for the identification of the raspberry root rot pathogen Phytophthora fragariae var. rubi. Furthermore, a nested PCR suitable for the detection of the pathogen in infected raspberry roots and validated against the "Duncan bait test" (EPPO Bull 35:87-91, 2005) is explained. Protocols for different DNA extraction methods are given which can be transferred to other fungal pathogens.

  10. A novel cytotoxic neophysalin from Physalis alkekengi var. francheti

    Institute of Scientific and Technical Information of China (English)

    Chu Hang Zhang; Zheng Tao Wang; Yi Ping Yang; Qi Shi Sun

    2009-01-01

    A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A(1), along with three other known neophysalins (2-4) were isolated from the calyxes of Physalis alkekengi L. var.francheti (Mast.) Makino. The structure of 1 was determined by means of ID and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC-3 and LNCaP cell lines.

  11. VaR without correlations for portfolio of derivative securities

    OpenAIRE

    Barone-Adesi, Giovanni; Giannopoulos, Kostas; Vosper, Les

    2008-01-01

    We propose filtering historical simulation by GARCH processes to model the future distribution of assets and swap values. Options’ price changes are computed by full reevaluation on the changing prices of underlying assets. Our methodology takes implicitly into account assets’ correlations without restricting their values over time or computing them explicitly. VaR values for portfolios of derivative securities are obtained without linearising them. Historical simulation assigns equal probabi...

  12. Probiotic Activity of Saccharomyces cerevisiae var. boulardii Against Human Pathogens

    Directory of Open Access Journals (Sweden)

    Katarzyna Rajkowska

    2012-01-01

    Full Text Available Infectious diarrhoea is associated with a modification of the intestinal microflora and colonization of pathogenic bacteria. Tests were performed for seven probiotic yeast strains of Saccharomyces cerevisiae var. boulardii, designated for the prevention and treatment of diarrhoea. To check their possible effectiveness against diarrhoea of different etiologies, the activity against a variety of human pathogenic or opportunistic bacteria was investigated in vitro. In mixed cultures with S. cerevisiae var. boulardii, a statistically significant reduction was observed in the number of cells of Listeria monocytogenes, Pseudomonas aeruginosa and Staphylococcus aureus, by even 55.9 % in the case of L. monocytogenes compared with bacterial monocultures. The influence of yeasts was mostly associated with the shortening of the bacterial lag phase duration, more rapid achievement of the maximum growth rates, and a decrease by 4.4–57.1 % (L. monocytogenes, P. aeruginosa, or an increase by 1.4–70.6 % (Escherichia coli, Enterococcus faecalis, Salmonella Typhimurium in the exponential growth rates. Another issue included in the research was the ability of S. cerevisiae var. boulardii to bind pathogenic bacteria to its cell surface. Yeasts have shown binding capacity of E. coli, S. Typhimurium and additionally of S. aureus, Campylobacter jejuni and E. faecalis. However, no adhesion of L. monocytogenes and P. aeruginosa to the yeast cell wall was noted. The probiotic activity of S. cerevisiae var. boulardii against human pathogens is related to a decrease in the number of viable and active cells of bacteria and the binding capacity of yeasts. These processes may limit bacterial invasiveness and prevent bacterial adherence and translocation in the human intestines.

  13. Potential Endophytic Bacteria for Increasing Paddy Var Rojolele Productivity

    Directory of Open Access Journals (Sweden)

    Desriani Desriani

    2013-09-01

    Full Text Available Paddy var Rojoleleis asuperior paddy come from Klaten that released by Department of Agriculture in 2003. Its superior properties are resistant to pests leaf hoppers, fluffier, and fragrant. To increase the productivity of paddy that are of ten used by farmers is to use chemical-based fertilizers. The use of these chemicals will effect to adisruption of ecosystem balancing, reduction the amount of soil microflora which essential forplants. Endophytic bacteria are symbiotic microorganisms living within plant tissues, and does not cause negative effects on the host plant. Endophytic bacteria have a capability increasing crop productivity by producing growth hormone, contributes to plant health, and as bio-control agents. Some endophytic bacteria which contribute to plant growth are: Pseudomonas sp., Enterobacter sp., Staphylococcus sp., Azotobacter sp., And Azospirilum sp., Whereas endophytic bacteria that contribute to the health and plant protection several of them are: Pseudomonas sp., Serratia sp. ,Clavibacter sp., and Bacillus sp. This study was conducted to investigate potential of endophytic bacteria to increase Paddy var Rojolele productivity based on its ability to produce extracellular enzymes and resistance to multiple types of antibiotics. The method were endophytic bacteria isolation from three Paddy varRojolele plants, extracellular enzymes detection and antibiotic resistance testing to chloramfinekol, ampicillin and kanamycin. As the result, 43isolateswere isolated from Paddy var Rojolele. Four isolatesamong them havethe ability to produce extra cellular enzym esandresistant toampicillin, kanamycin, and chloramfinekol. Extra cellular enzyme production capability and resistance to antibiotics makes endophytic bacteria are potentialto improveplant health and also asbio-control agentwhich then willaffect to the productivity of rice. To further ensure its potential to plant, more research is needed.

  14. REDESCUBRIMIENTO DE MYRRHINIUM ATROPURPUREUM VAR. OCTANDRUM (MYRTACEAE: MYRTINAE EN COLOMBIA

    Directory of Open Access Journals (Sweden)

    PARRA-O. CARLOS

    2003-12-01

    Full Text Available Se documenta el redescubrimiento de Myrrhinium atropurpureum var. octandrum(Myrteae DC., Myrtaceae, taxón prácticamente desconocido en Colombia. Se presentala descripción del taxón, así como notas sobre su distribución en Colombia, elhábitat en que se desarrolla y su posible estatus dentro de las categorías de la ListaRoja de la UICN.

  15. A Structural VAR Approach to Estimating Budget Balance Targets

    OpenAIRE

    Robert A Buckle; Kunhong Kim; Julie Tam

    2001-01-01

    The Fiscal Responsibility Act 1994 states that, as a principle of responsible fiscal management, a New Zealand government should ensure total Crown debt is at a prudent level by ensuring total operating expenses do not exceed total operating revenues. In this paper a structural VAR model is estimated to evaluate the impact on the government's cash operating surplus (or budget balance) of four independent disturbances: supply, fiscal, real private demand, and nominal disturbances. Based on the...

  16. On the way of tobacco quitting: A VAR approach

    OpenAIRE

    Nicolas Gérard Vaillant; Christian Ben lakhdar; Thérèse Lebrun

    2011-01-01

    In order to describe the process of tobacco quitting, we perform a VAR model and causality tests both on the monthly sales of tobacco products and nicotine dependence drugs in France, for the period going from February 2004 to April 2009. According to the path of tobacco quitting found out, it results that an upward harmonization of tax policy on the different tobacco products could accelerate the tobacco quitting process.

  17. New lignans from the heartwood of Chamaecyparis obtusa var. formosana.

    Science.gov (United States)

    Kuo, Yueh-Hsiung; Chen, Chia-Hsien; Lin, Yun-Lian

    2002-07-01

    Four new lignans, 3',4'-O,O-demethylenehinokinin (1), chamalignolide (2), 8'beta-hydroxyhinokinin (3) and 7beta,8beta-epoxyzuonin A (4), as well as (-)-hinokinin (5), and (-)-zuonin A (6), were isolated from the heartwood of Chamaecyparis obtusa var. formosana. The structures of these lignans were unambiguously determined by spectroscopic methods. And the absolute configuration of 1 was elucidated with a circular dichroism (CD) spectrum.

  18. Development and Evaluation of a Molecular Diagnostic Method for Rapid Detection of Histoplasma capsulatum var. farciminosum, the Causative Agent of Epizootic Lymphangitis, in Equine Clinical Samples.

    Science.gov (United States)

    Scantlebury, C E; Pinchbeck, G L; Loughnane, P; Aklilu, N; Ashine, T; Stringer, A P; Gordon, L; Marshall, M; Christley, R M; McCarthy, A J

    2016-12-01

    Histoplasma capsulatum var. farciminosum, the causative agent of epizootic lymphangitis (EZL), is endemic in parts of Africa. Diagnosis based on clinical signs and microscopy lacks specificity and is a barrier to further understanding this neglected disease. Here, a nested PCR method targeting the internal transcribed spacer (ITS) region of the rRNA operon was validated for application to equine clinical samples. Twenty-nine horses with signs of EZL from different climatic regions of Ethiopia were clinically examined. Blood samples and aspirates of pus from cutaneous nodules were taken, along with blood from a further 20 horses with no cutaneous EZL lesions. Among the 29 horses with suspected cases of EZL, H. capsulatum var. farciminosum was confirmed by extraction of DNA from pus and blood samples from 25 and 17 horses, respectively. Positive PCR results were also obtained with heat-inactivated pus (24 horses) and blood (23 horses) spotted onto Whatman FTA cards. Two positive results were obtained among blood samples from 20 horses that did not exhibit clinical signs of EZL. These are the first reports of the direct detection of H. capsulatum var. farciminosum in equine blood and at high frequency among horses exhibiting cutaneous lesions. The nested PCR outperformed conventional microscopic diagnosis, as characteristic yeast cells could be observed only in 14 pus samples. The presence of H. capsulatum var. farciminosum DNA was confirmed by sequencing the cloned PCR products, and while alignment of the ITS amplicons showed very little sequence variation, there was preliminary single nucleotide polymorphism-based evidence for the existence of two subgroups of H. capsulatum var. farciminosum This molecular diagnostic method now permits investigation of the epidemiology of EZL.

  19. Effects of NaCl Stress on Chlorophyll Fluorescence Parameters in Cinnamomum japonicum var. chenii%NaCl胁迫对普陀樟叶绿素荧光参数的影响

    Institute of Scientific and Technical Information of China (English)

    李影丽; 汪奎宏; 杜国坚; 许利群; 杨华; 肖纪军

    2008-01-01

    [Objective] Study on the changes of chlorophyll fluorescence parameters in Cinnamomum japonicum var. chenii under NaCl stress. [Method] The seedling growth increment, chlorophyll content and chlorophyll fluorescence parameters in leaves of 1-year old Cinnamomum japonicum var. chenii were investigated in field experiment. [Result] Under NaCl stress, seedling growth increment reduced and the chlorophyll content decreased to a stable value; changes of Fv/Fm and Fv/Fo showed identical increasing trend and double peak type. With the aggravation of salt stress, most variations were ob- served in Fo, correlations among chlorophyll fluorescence parameters presented "rise-drop" trend (in the treatment of 7 g/L NaCl). [Condusion] Cinna-momum japonicum var. chenii is endowed with strong salt resistance and wide adaptability.

  20. Characterization of novel microsatellite markers in Musa acuminata subsp. burmannicoides, var. Calcutta 4

    Directory of Open Access Journals (Sweden)

    Amorim Edson P

    2010-05-01

    Full Text Available Abstract Background Banana is a nutritionally important crop across tropical and sub-tropical countries in sub-Saharan Africa, Central and South America and Asia. Although cultivars have evolved from diploid, triploid and tetraploid wild Asian species of Musa acuminata (A genome and Musa balbisiana (B genome, many of today's commercial cultivars are sterile triploids or diploids, with fruit developing via parthenocarpy. As a result of restricted genetic variation, improvement has been limited, resulting in a crop frequently lacking resistance to pests and disease. Considering the importance of molecular tools to facilitate development of disease resistant genotypes, the objectives of this study were to develop polymorphic microsatellite markers from BAC clone sequences for M. acuminata subsp. burmannicoides, var. Calcutta 4. This wild diploid species is used as a donor cultivar in breeding programs as a source of resistance to diverse biotic stresses. Findings Microsatellite sequences were identified from five Calcutta 4 BAC consensi datasets. Specific primers were designed for 41 loci. Isolated di-nucleotide repeat motifs were the most abundant, followed by tri-nucleotides. From 33 tested loci, 20 displayed polymorphism when screened across 21 diploid M. acuminata accessions, contrasting in resistance to Sigatoka diseases. The number of alleles per SSR locus ranged from two to four, with a total of 56. Six repeat classes were identified, with di-nucleotides the most abundant. Expected heterozygosity values for polymorphic markers ranged from 0.31 to 0.75. Conclusions This is the first report identifying polymorphic microsatellite markers from M. acuminata subsp. burmannicoides, var. Calcutta 4 across accessions contrasting in resistance to Sigatoka diseases. These BAC-derived polymorphic microsatellite markers are a useful resource for banana, applicable for genetic map development, germplasm characterization, evolutionary studies and marker

  1. Analysis list: Su(var)3-7 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Su(var)3-7 Adult,Embryo,Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3.../target/Su(var)3-7.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/Su(var)3-7.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/dm3/target/Su(var)3-7.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/c...olo/Su(var)3-7.Adult.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(v...ar)3-7.Embryo.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(var)3-7.Larvae.tsv http://dbarchive.bioscience

  2. Differential expression of genes involved in entomopathogenicity of the fungi Metarhizium anisopliae var. anisopliae and M. anisopliae var. acridum (Clavicipitaceae).

    Science.gov (United States)

    Carneiro-Leão, M P; Andreote, F D; Araújo, W L; Oliveira, N T

    2011-05-03

    Expression analysis of the genes involved in germination, conidiogenisis and pathogenesis of Metarhizium anisopliae during its saprophytic and pathogenic life stages can help plan strategies to increase its efficacy as a biological control agent. We quantified relative expression levels of the nitrogen response regulator gene (nrr1) and a G-protein regulator of genes involved in conidiogenesis (cag8), using an RT-qPCR assay. Comparisons were made between M. anisopliae var. anisopliae and M. anisopliae var. acridum during germination and conidiogenesis and at different stages of pathogenesis. The cag8 gene was repressed during germination and induced during conidial development and the pathogenic phase, and the nrr1 gene was induced during germination, conidiogenesis and the pathogenic phase. Both genes were more expressed in M. anisopliae var. anisopliae, demonstrating that different varieties of M. anisopliae differ in activation of genes linked to virulence for certain environments and hosts. This suggests that differences among these varieties in the ability to adapt could be attributed not only to specific genomic regions and genes, but also to differential gene expression in this fungus, modulating its ability to respond to environmental stimuli.

  3. VT-1161 Protects Immunosuppressed Mice from Rhizopus arrhizus var. arrhizus Infection.

    Science.gov (United States)

    Gebremariam, Teclegiorgis; Wiederhold, Nathan P; Fothergill, Annette W; Garvey, Edward P; Hoekstra, William J; Schotzinger, Robert J; Patterson, Thomas F; Filler, Scott G; Ibrahim, Ashraf S

    2015-12-01

    We studied the efficacy of the investigational drug VT-1161 against mucormycosis. VT-1161 had more potent in vitro activity against Rhizopus arrhizus var. arrhizus than against R. arrhizus var. delemar. VT-1161 treatment demonstrated dose-dependent plasma drug levels with prolonged survival time and lowered tissue fungal burden in immunosuppressed mice infected with R. arrhizus var. arrhizus and was as effective as high-dose liposomal amphotericin B treatment. These results support further development of VT-1161 against mucormycosis.

  4. Genomic Rearrangements Associated with Antigenic Variation in Campylobacter coli

    Science.gov (United States)

    1988-01-01

    AU’rHORS) P. Guerrv, S.M. Logan, and T.J. Trust. 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE COUNT Journal article ...level. Olsen, N. R. Pace, and D. A. Stahl. 1987. Campylohacterpylori. the spiral bacterium associated with human gastritis , is not a true Campylobacter

  5. Antigenic variation and resistance to neutralization in poliovirus type 1.

    NARCIS (Netherlands)

    D.C. Diamond; B.A. Jameson; J. Bonin; M. Kohara; S. Abe; H. Itoh; T. Komatsu; M. Arita; S. Kuge; A. Nomoto; A.D.M.E. Osterhaus (Albert); R. Crainic; E. Wimmer

    1985-01-01

    textabstractMutations have been identified in variants of poliovirus, type 1 (Mahoney) on the basis of their resistance to neutralization by individual monoclonal antibodies. The phenotypes of these variants were defined in terms of antibody binding; the pattern of epitopes expressed or able to be e

  6. Utilizing nanobody technology to target non-immunodominant domains of VAR2CSA

    DEFF Research Database (Denmark)

    Ditlev, Sisse B; Florea, Raluca; Nielsen, Morten A

    2014-01-01

    and maternal anemia. IE accumulation is supported by the binding of the parasite-expressed protein VAR2CSA to placental chondroitin sulfate A (CSA). Defining specific CSA-binding epitopes of VAR2CSA, against which to target the immune response, is essential for the development of a vaccine aimed at blocking IE...... adhesion. However, the development of a VAR2CSA adhesion-blocking vaccine remains challenging due to (i) the large size of VAR2CSA and (ii) the extensive immune selection for polymorphisms and thereby non-neutralizing B-cell epitopes. Camelid heavy-chain-only antibodies (HcAbs) are known to target epitopes...

  7. Variational data assimilation with superparameterization

    Directory of Open Access Journals (Sweden)

    I. Grooms

    2015-03-01

    Full Text Available Superparameterization (SP is a multiscale computational approach wherein a large scale atmosphere or ocean model is coupled to an array of simulations of small scale dynamics on periodic domains embedded into the computational grid of the large scale model. SP has been successfully developed in global atmosphere and climate models, and is a promising approach for new applications. The authors develop a 3D-Var variational data assimilation framework for use with SP; the relatively low cost and simplicity of 3D-Var in comparison with ensemble approaches makes it a natural fit for relatively expensive multiscale SP models. To demonstrate the assimilation framework in a simple model, the authors develop a new system of ordinary differential equations similar to the two-scale Lorenz-'96 model. The system has one set of variables denoted {Yi}, with large and small scale parts, and the SP approximation to the system is straightforward. With the new assimilation framework the SP model approximates the large scale dynamics of the true system accurately.

  8. Dynamics of anti-VAR2CSA immunoglobulin G response in a cohort of senegalese pregnant women

    DEFF Research Database (Denmark)

    Tuikue Ndam, N G; Salanti, A; Le-Hesran, J-Y;

    2006-01-01

    (VSAPAM). Several studies have shown that 1 var gene, var2csa, is transcribed at high levels and expressed in CSA-binding Plasmodium falciparum parasites. METHODS: Plasma levels of anti-VAR2CSA immunoglobulin G (IgG) in Senegalese women were measured during pregnancy by enzyme-linked immunosorbent assay...... demonstrated that a single P. falciparum infection was able to trigger a VAR2CSA-specific antibody response. Among women with infected placentas, women with high anti-VAR2CSA IgG levels at enrollment were more likely to present with a past infection than with an acute/chronic infection. CONCLUSIONS: Anti-VAR2...

  9. Polymorphism and methylation patterns in Agave tequilana Weber var. 'Azul' plants propagated asexually by three different methods.

    Science.gov (United States)

    Díaz-Martínez, Miriam; Nava-Cedillo, Alejandro; Guzmán-López, José Alfredo; Escobar-Guzmán, Rocío; Simpson, June

    2012-04-01

    Genetic variation in three forms of asexually propagated Agave tequilana Weber var. 'Azul' plants namely offsets, bulbils and in vitro cultured individuals was studied by AFLP analysis. Low levels of variation were observed between mother plants and offsets and a higher level between mother plant and bulbils. Families obtained from commercial plantations showed lower levels of variation in comparison to families grown as ornamentals. No variation was observed between the original explant and four generations of in vitro cultured plants. Epigenetic variation was also studied by analyzing changes in methylation patterns between mother plants and offspring in each form of asexual reproduction. Offsets and bulbils showed an overall decrease in methylation whereas in vitro cultured plants showed patterns specific to each generation: Generations 1 and 4 showed overall demethylation whereas Generations 2 and 3 showed increased methylation. Analysis of ESTs associated with transposable elements revealed higher proportions of ESTs from Ty1-copia-like, Gypsy and CACTA transposable elements in cDNA libraries obtained from pluripotent tissue suggesting a possible correlation between methylation patterns, expression of transposable element associated genes and somaclonal variation.

  10. Isolation of the Endophytic Fungi of Paris polyphylla var. yunnanensis and Their Effects on the Embryo Development of P. polyphylla var. yunnanensis Seeds

    Institute of Scientific and Technical Information of China (English)

    Kun CHENG; Yanqiong YANG; Changling ZHAO; Li WANG; Shuying CHEN; Yuhan SHEN; Jing CHAI; Key words Paris polyphylla var. yunnanensis; Endophytic fungus; P. polyphylla var. yunnanensis seed; Embryo development; Embryo

    2012-01-01

    Abstract [Objective] This study aimed to isolate the endophytic fungi of Paris poly- phylla var. yunnanensis and investigate their effects on the embryo development of P. polyphylla var. yunnanensis seeds. [Method] The endophytic fungi of P. poly- phylla were isolated and identified morphologically, and their effects on the embryo development of P. polyphylla var. yunnanensis seeds were studied by using paraffin sectioning and microphotography. [Result] Nine endophytic fungi, Le. P. polyphylla var. yunnanensis endophytic fungi PPYEF-1, PPYEF-2, PPYEF-3, PPYEF-4, PPYEF- 5, PPYEF-6, PPYEF-7, PPYEF-8 and PPYEF-9 belonging to seven genera in five families, three orders were isolated from the rhizomes. Except PPYEF-4 (Cladospori- um sp.), other fungi could promote the embryo development of the P. polyphylla var. yunnanensis seeds, mostly reaching the extremely significant or significant level. PPYEF-9 (Trichoderma sp.) resulted in the highest embryo length and embryo-e- merging ratio. [Conclusion] This paper could provide a reference for the applica- tion of the endophytic fungi of P. polyphylla var. yunnanensis in the dormancy- breaking of P. polyphylla var. yunnanensis seeds.

  11. Oncogenic cancer/testis antigens

    DEFF Research Database (Denmark)

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-01-01

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

  12. A culture of Salmonella infantis of complex antigenic constitution.

    Science.gov (United States)

    EDWARDS, P R; McWHORTER, A C; DOUGLAS, G W

    1962-07-01

    Edwards, P. R. (Communicable Disease Center, U.S. Public Health Service, Atlanta, Ga.), A. C. McWhorter, and G. W. Douglas. A culture of Salmonella infantis of complex antigenic constitution. J. Bacteriol. 84:95-98. 1962-An antigenically complex Salmonella serotype (6,7:z(49),r:z(49),1,5), in which the antigen z(49) is a major component of both phases, is described. Through loss variation, this form gives rise to cultures identical with S. infantis (6,7:r:1,5). Attention is drawn to the similarity of its behavior to that of S. montgomery and S. salinatis, and the possible origin of such complex forms is discussed briefly. The organism is not assigned a name, but is considered simply as a complex form of S. infantis.

  13. Epicutaneous sensitization with protein antigen

    Directory of Open Access Journals (Sweden)

    I-Lin Liu

    2012-12-01

    Full Text Available In the past few decades there has been a progressive understanding that epicutaneous sensitization with protein antigen is an important sensitization route in patients with atopic dermatitis. A murine protein-patch model has been established, and an abundance of data has been obtained from experiments using this model. This review discusses the characteristics of epicutaneous sensitization with protein antigen, the induced immune responses, the underlying mechanisms, and the therapeutic potential.

  14. Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides).

    Science.gov (United States)

    Thies, Judy A; Ariss, Jennifer J; Kousik, Chandrasekar S; Hassell, Richard L; Levi, Amnon

    2016-03-01

    Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees of resistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN.

  15. Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides)

    Science.gov (United States)

    Thies, Judy A.; Ariss, Jennifer J.; Kousik, Chandrasekar S.; Hassell, Richard L.; Levi, Amnon

    2016-01-01

    Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees of resistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN. PMID:27168648

  16. Alkaloid content of the seeds from Erythroxylum Coca var. Coca.

    Science.gov (United States)

    Casale, John F; Toske, Steven G; Colley, Valerie L

    2005-11-01

    Alkaloid extracts from the seeds of Erythroxylum Coca var. Coca grown in the Chapare Valley of Bolivia were subjected to gas and liquid chromatographic-mass spectrometric analyses. Several alkaloids from these seeds were detected and characterized, including methylecgonidine, tropine, 3alpha-acetoxytropane, ecgonine methyl ester, cuscohygrine, N-norbenzoyltropine, benzoyltropine, hexanoylecgonine methyl ester, cocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine. Methylecgonidine was determined to be the primary constituent and not an analytical artifact. Additionally, two significant new uncharacterized alkaloids were established as present. Recent evidence suggests that some cocaine processors are adding this seed extraction material to cocaine extracted from coca leaf and may impact cocaine impurity signature profiles.

  17. [Chemical constituents from roots of Chirita longgangensis var. hongyao].

    Science.gov (United States)

    Huang, Hai-Jiang; He, Lan-Yun

    2014-03-01

    To study the chemical constituents from the roots of Chirita longgangensis var. hongyao. The methanol extract was isolated and purified by silica gel, Sephadex LH-20 and preparative HPLC. Their structures were elucidated by MS and spectral data (1H, 13C-NMR). Seven compounds were isolated and identified as plantainoside A (1), plantainoside B (2), calcedarioside C (3), calcedarioside D (4), platyphylloside (5), hirsutanonol (6), and hirsutanonol-5-O-beta-D-glucopyranoside (7). Compounds 5-7 were isolated for the first time from the family Gesneriaceae.

  18. Novel diterpenes from the heartwood of Chamaecyparis obtusa var. formosana.

    Science.gov (United States)

    Kuo, Yueh-Hsiung; Chen, Chia-Hsien; Chien, Shih-Chang; Lin, Hsiu-Chuan

    2004-06-01

    Two novel diterpenes, obtusanal B (1) and obtusadione (2), along with obtusanal A (3), obtunone (4), 12-hydroxy-6,7-secoabieta-8,11,13-triene-6,7-dial, 8,12-dihydroxydielmentha-5,9-diene-7,11-dione and myrcene, isolated from the heartwood of Chamaecyparis obtusa var. formosana, were characterized by spectroscopic means, including 2D-NMR techniques. Compounds 1 and 2 are 7(6-->2)abeoabietane and 14(8-->9)abeoabietane type diterpenes, respectively. Their biosyntheses were proposed.

  19. A New Languidulane Diterpenoid from Salvia mexicana var. mexicana

    Directory of Open Access Journals (Sweden)

    Jorge Cárdenas

    2011-10-01

    Full Text Available From the aerial parts of Salvia mexicana var. mexicana, two C-10 epimers (α and β of salvimexicanolide were isolated. Our interpretation of the data, especially the 13C NMR, led us to conclude that the previously described 13C-NMR spectrum of the α-epimer was not accurately assigned and it actually corresponds to the β-epimer. The structures proposed for the salvimexicanolides were verified by means of NOESY experiments. Dugesin B, arbutin, naringenin and the mixture of oleanolic and ursolic acids were also isolated from this Salvia spp.

  20. Labor Costs and Foreign Direct Investment: A Panel VAR Approach

    Directory of Open Access Journals (Sweden)

    Bahar Bayraktar-Sağlam

    2017-09-01

    Full Text Available This paper examines the endogenous interaction between labor costs and Foreign Direct Investment (FDI in the OECD countries via the Panel VAR approach under system GMM estimates for the period 1995–2009. The available data allows identifying the relevance of the components of labor costs, and allows a detailed analysis across different sectors. Empirical findings have revealed that sectoral composition of FDI and the decomposition of labor costs play a significant role in investigating the dynamic association between labor costs and FDI. Further, results suggest that labor market policies should focus on productivity-enhancing tools in addition to price hindering tools.

  1. Phenolic compounds from the roots of Valeriana officinalis var. latifolia

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng-Cheng; Ran, Xin-Hui; Luo, Huai-Rong; Liu, Yu-Qing; Zhou Jun [State Key Laboratory of Phytochemistry and Plant Resources in West China. Kunming Institute of Botany, Chinese Academy of Sciences (China); Ma, Qing-Yun; Zhao, You-Xing, E-mail: zhoujun3264@yahoo.com.cn, E-mail: zhaoyouxing@itbb.org.cn [Key Laboratory of Biology and Genetic Resources of Tropical Crops. Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology. Chinese Academy of Tropical Agriculture Sciences (China)

    2013-09-15

    A new benzofuran neolignan, dihydrodehydrodiconiferyl alcohol 9-isovalerate, along with ten known phenolic compounds, olivil, pinoresinol, 8-hydroxypinoresinol, pinorespiol, 8-hydroxy- 7-epipinoresinol, trans-p-hydroxyphenyl- propenoic acid, cis-p-hydroxyphenyl-propenoic acid, ferulic acid, isoferulic acid and isovanillin were isolated from the roots of Valeriana officinalis var. latifolia. Their structures and configurations were elucidated on the basis of spectroscopic methods. The inhibitory activity for acetylcholinesterase (AChE) and enhancing activity on nerve growth factor (NGF)-mediated neurite outgrowth in PC12 cells of dihydrodehydrodiconiferyl alcohol 9-isovaterate and olivil were evaluated. (author)

  2. Mutagénesis y antimutagénesis en extractos acuosos, clorofórmicos y acetónicos de Ilex paraguariensis var. paraguariensis e Ilex dumosa var. dumosa

    OpenAIRE

    2011-01-01

    El presente trabajo tuvo por finalidad investigar los posibles efectos mutagénicos y antimutagénicos de dos variedades de Ilex (Ilex paraguariensis var. paraguariensis e Ilex dumosa var. dumosa) empleadas corrientemente en la elaboración de infusiones utilizando ensayos de mutagenicidad in vitro (Ensayo de Salmonella microsoma) e in vivo (Test de Micronúcleo). Se trabajó con Ilex paraguariensis St Hil. var. paraguariensis e Ilex dumosa Reissek var. dumosa, ejemplares frescos proveni...

  3. Ulmus davidiana var. japonica Nakai upregulates eosinophils and suppresses Th1 and Th17 cells in the small intestine.

    Directory of Open Access Journals (Sweden)

    Han-Sung Lee

    Full Text Available The bark of Ulmus davidiana var. japonica Nakai (Ulmaceae has been used in traditional Korean medicine for chronic inflammation in the gastrointestinal tract. Here we investigated the frequency and cytokine profile of the major immune cells in the small intestinal lamina propria (SI LP, spleen, and mesenteric lymph nodes (MLNs of mice treated orally with Ulmus davidiana var. japonica Nakai bark water extract (UDE to address the immunomodulatory role of this herb in intestinal homeostasis. B6 mice were given 5g/kg UDE once daily for 14 days. They were then sacrificed, and cells were isolated from the spleen, MLNs, and SI LP. The proportion of B versus T lymphocytes, CD4(+ versus CD8(+ T lymphocytes, Th1 and Th17 cells, and Foxp3(+ regulatory T cells in the spleen, MLNs, and SI LP were analyzed. The frequency of antigen-presenting cells (APCs, including dendritic cells, macrophages, and eosinophils in the SI LP and the expression of costimulatory molecules on APCs were also evaluated. The numbers and frequencies of Th1 and Th17 cells in the SI LP were significantly reduced in the UDE-treated mice compared with PBS controls. In addition, the proportion of IL-4-producing eosinophils in the SI LP was significantly elevated in the UDE-treated mice compared with controls. Taken together, these data indicate that UDE up-regulates the number and frequency of SI LP eosinophils, which can down-regulate the Th1 and Th17 responses via IL-4 secretion and contribute to intestinal homeostasis.

  4. Phase variable O antigen biosynthetic genes control expression of the major protective antigen and bacteriophage receptor in Vibrio cholerae O1.

    Directory of Open Access Journals (Sweden)

    Kimberley D Seed

    2012-09-01

    Full Text Available The Vibrio cholerae lipopolysaccharide O1 antigen is a major target of bacteriophages and the human immune system and is of critical importance for vaccine design. We used an O1-specific lytic bacteriophage as a tool to probe the capacity of V. cholerae to alter its O1 antigen and identified a novel mechanism by which this organism can modulate O antigen expression and exhibit intra-strain heterogeneity. We identified two phase variable genes required for O1 antigen biosynthesis, manA and wbeL. manA resides outside of the previously recognized O1 antigen biosynthetic locus, and encodes for a phosphomannose isomerase critical for the initial step in O1 antigen biosynthesis. We determined that manA and wbeL phase variants are attenuated for virulence, providing functional evidence to further support the critical role of the O1 antigen for infectivity. We provide the first report of phase variation modulating O1 antigen expression in V. cholerae, and show that the maintenance of these phase variable loci is an important means by which this facultative pathogen can generate the diverse subpopulations of cells needed for infecting the host intestinal tract and for escaping predation by an O1-specific phage.

  5. Antioxidant, free radical scavenging and invitro cytotoxic studies of ethanolic extract of Leucas indica var lavandulifolia and Leucas indica var nagalapuramiana

    Institute of Scientific and Technical Information of China (English)

    Ramalingam Ramani; Sushruthi Sudini; Bindu Madhavi Boddupalli; Ravinder Nath Anisetti

    2012-01-01

    Objective: The main focus of the study is to determine antioxidant, free radical scavenging and cytotoxic effect of ethanolic extract of whole plant of Leucas indica var lavandulifolia and Leucas indica var nagalapuramiana using various in vitro assay methods as well as to estimate the amount of total phenol and flavonoid contents. Methods: Leucas indica var lavandulifolia and Leucas indica var nagalapuramiana were collected in February 2008 from Thirumala hills and standard procedure from the literature were used to estimate the antioxidant and free radical scavenging activity. Results: The results suggest that both the extracts can be considered as a valuable source of antioxidants products as the obtained values are more or less near to the used standard compound. Conclusions: The characterization of leucas for antioxidant and free radical scavenging activities are new to literature in this context this extensive in vitro study of the selected two species of leucas for antioxidant activity will be a valuable study for further in vivo activities.

  6. Silence, Metaperformance, and Communication in Pedro Almodóvar's "Hable con ella"

    Science.gov (United States)

    Fellie, Maria C.

    2016-01-01

    Many scenes in Pedro Almodóvar's "Hable con ella" (2002) include shots of metaperformances such as silent films, dances, television shows, concerts, and bullfights. Spectators often observe passive characters who are in turn observing. By presenting these performances within cinematic performance, Almodóvar highlights our role as viewers…

  7. Primulina beiliuensis var. fimbribracteata (Gesneriaceae, a New Variety in A Limestone Cave from Northern Guangdong, China

    Directory of Open Access Journals (Sweden)

    Bi-Dan Lai

    2015-03-01

    Full Text Available Primulina beiliuensis var. fimbribracteata F. Wen & B.D. Lai, a new variety of Gesneriaceae from a limestone cave in Shaoguan, Guangdong, China, is described and illustrated in this report. This new species is similar to P. beiliuensis B. Pan & S.X. Huang var. beiliuensis, but easily differs from the type variety in several morphological characters, both vegetative and reproductive.

  8. Primulina beiliuensis var. fimbribracteata (Gesneriaceae), a New Variety in A Limestone Cave from Northern Guangdong, China

    OpenAIRE

    Bi-Dan Lai; Fang Wen

    2015-01-01

    Primulina beiliuensis var. fimbribracteata F. Wen & B.D. Lai, a new variety of Gesneriaceae from a limestone cave in Shaoguan, Guangdong, China, is described and illustrated in this report. This new species is similar to P. beiliuensis B. Pan & S.X. Huang var. beiliuensis, but easily differs from the type variety in several morphological characters, both vegetative and reproductive.

  9. A Stochastic Dominance Approach to the Basel III Dilemma: Expected Shortfall or VaR?

    NARCIS (Netherlands)

    C-L. Chang (Chia-Lin); J.A. Jiménez-Martín (Juan-Ángel); E. Maasoumi (Esfandiar); M.J. McAleer (Michael); T. Pérez-Amaral (Teodosio)

    2015-01-01

    markdownabstract__Abstract__ The Basel Committee on Banking Supervision (BCBS) (2013) recently proposed shifting the quantitative risk metrics system from Value-at-Risk (VaR) to Expected Shortfall (ES). The BCBS (2013) noted that “a number of weaknesses have been identified with using VaR for deter

  10. Scleria neesii Kunth var. gadchiroliensis (Cyperaceae, a New Variety from Central India

    Directory of Open Access Journals (Sweden)

    Milind M. Sardesai

    2015-12-01

    Full Text Available A new variety of Scleria P. J. Bergius (Cyperaceae S. neesii Kunth var. gadchiroliensis from Central India is described here with description, line-drawing, photographic illustration and notes. It resembles with S. neesii Kunth var. neesii in overall morphology but differs in having milky white nuts covered with ribbon like hairs on distinct stalk.

  11. Coumarins from Murraya paniculata var. zollingeri endemic to the Timor Islands.

    Science.gov (United States)

    Teshima, Naoko; Yamada, Hiromi; Ju-ichi, Motoharu; Uji, Tahan; Kinoshita, Takeshi; Ito, Chihiro

    2015-02-01

    Four new coumarins, murrangatin-1'-senecioate (1), 5-methoxypanial (2), mexoticin-2'-senecioate (3) and murralongic acid (4), were isolated from the leaves of Murraya paniculata var. zollingeri, together with 23 known coumarins. The structures of the new compounds were elucidated based on spectroscopic data. The taxonomic status of M. paniculata var. zollingeri is briefly discussed, along with its similarity to M. paniculata.

  12. Impact of advanced technology microwave sounder data in the NCMRWF 4D-VAR data assimilation system

    Science.gov (United States)

    Rani, S. Indira; Srinivas, D.; Mallick, Swapan; George, John P.

    2016-05-01

    This study demonstrates the added benefits of assimilating the Advanced Technology Microwave Sounder (ATMS) radiances from the Suomi-NPP satellite in the NCMRWF Unified Model (NCUM). ATMS is a cross-track scanning microwave radiometer inherited the legacy of two very successful instrument namely, Advanced Microwave Sounding Unit-A (AMSU-A) and Microwave Humidity Sounder (MHS). ATMS has 22 channels: 11 temperature sounding channels around 50-60 GHz oxygen band and 6 moisture sounding channels around the 183GHz water vapour band in addition to 5 channels sensitive to the surface in clear conditions, or to water vapour, rain, and cloud when conditions are not clear (at 23, 31, 50, 51 and 89 GHz). Before operational assimilation of any new observation by NWP centres it is standard practice to assess data quality with respect to NWP model background (short-forecast) fields. Quality of all channels is estimated against the model background and the biases are computed and compared against that from the similar observations. The impact of the ATMS data on global analyses and forecasts is tested by adding the ATMS data in the NCUM Observation Processing system (OPS) and 4D-Var variational assimilation (VAR) system. This paper also discusses the pre-operational numerical experiments conducted to assess the impact of ATMS radiances in the NCUM assimilation system. It is noted that the performance of ATMS is stable and it contributes to the performance of the model, complimenting observations from other instruments.

  13. Phenolic Composition and Antioxidant and Antimicrobial Activities of Extracts Obtained from Crataegus azarolus L. var. aronia (Willd. Batt. Ovaries Calli

    Directory of Open Access Journals (Sweden)

    Radhia Bahri-Sahloul

    2014-01-01

    Full Text Available Objective. Plant cell culture is an innovative technology to produce a variety of substances. Numerous plants synthesize among their secondary metabolites phenolic compounds which possess antioxidant and antimicrobial effects. Hawthorn (Crataegus is one of these plants which has long been used in folk medicine and is widely utilized in pharmaceutical preparations mainly in neuro- and cardiosedative actions. Methods and Results. The production of polyphenol by fifty-two-week-old Crataegus azarolus var. aronia calli was studied in relation to growth variation and antioxidant and antimicrobial capacity within a subcultured period. The DPPH and ABTS+ assays were used to characterize the antioxidant actions of the callus cultures. Antimicrobial activity was tested by using disc diffusion and dilution assays for the determination of the minimal inhibitory concentration (MIC and the minimal bactericidal concentration (MBC values of each active extract. High TEACDPPH, TEACABTS, and antimicrobial activity was observed when maximal growth was reached. An optimum of total phenol, proanthocyanidins, flavonoid, (−-epicatechin, procyanidin B2, chlorogenic acid, and hyperoside was produced during this period. Conclusion. Antioxidant and antimicrobial activities were strongly correlated with total phenols and total flavonoids. Crataegus azarolus var. aronia cells culture represents an important alternative source of natural antioxidants and antimicrobials.

  14. Mapping the antigenicity of the parasites in Leishmania donovani infection by proteome serology.

    Directory of Open Access Journals (Sweden)

    Michael Forgber

    Full Text Available BACKGROUND: Leishmaniasis defines a cluster of protozoal diseases with diverse clinical manifestations. The visceral form caused by Leishmania donovani is the most severe. So far, no vaccines exist for visceral leishmaniasis despite indications of naturally developing immunity, and sensitive immunodiagnostics are still at early stages of development. METHODOLOGY/PRINCIPLE FINDINGS: Establishing a proteome-serological methodology, we mapped the antigenicity of the parasites and the specificities of the immune responses in human leishmaniasis. Using 2-dimensional Western blot analyses with sera and parasites isolated from patients in India, we detected immune responses with widely divergent specificities for up to 330 different leishmanial antigens. 68 antigens were assigned to proteins in silver- and fluorochrome-stained gels. The antigenicity of these proteins did not correlate with the expression levels of the proteins. Although some antigens are shared among different parasite isolates, there are extensive differences and no immunodominant antigens, but indications of antigenic drift in the parasites. Six antigens were identified by mass spectrometry. CONCLUSIONS/SIGNIFICANCE: Proteomics-based dissection of the serospecificities of leishmaniasis patients provides a comprehensive inventory of the complexity and interindividual heterogeneity of the host-responses to and variations in the antigenicity of the Leishmania parasites. This information can be instrumental in the development of vaccines and new immune monitoring and diagnostic devices.

  15. EnKF and 4D-Var data assimilation with chemical transport model BASCOE (version 05.06)

    Science.gov (United States)

    Skachko, Sergey; Ménard, Richard; Errera, Quentin; Christophe, Yves; Chabrillat, Simon

    2016-08-01

    We compare two optimized chemical data assimilation systems, one based on the ensemble Kalman filter (EnKF) and the other based on four-dimensional variational (4D-Var) data assimilation, using a comprehensive stratospheric chemistry transport model (CTM). This work is an extension of the Belgian Assimilation System for Chemical ObsErvations (BASCOE), initially designed to work with a 4D-Var data assimilation. A strict comparison of both methods in the case of chemical tracer transport was done in a previous study and indicated that both methods provide essentially similar results. In the present work, we assimilate observations of ozone, HCl, HNO3, H2O and N2O from EOS Aura-MLS data into the BASCOE CTM with a full description of stratospheric chemistry. Two new issues related to the use of the full chemistry model with EnKF are taken into account. One issue is a large number of error variance parameters that need to be optimized. We estimate an observation error variance parameter as a function of pressure level for each observed species using the Desroziers method. For comparison purposes, we apply the same estimate procedure in the 4D-Var data assimilation, where both scale factors of the background and observation error covariance matrices are estimated using the Desroziers method. However, in EnKF the background error covariance is modelled using the full chemistry model and a model error term which is tuned using an adjustable parameter. We found that it is adequate to have the same value of this parameter based on the chemical tracer formulation that is applied for all observed species. This is an indication that the main source of model error in chemical transport model is due to the transport. The second issue in EnKF with comprehensive atmospheric chemistry models is the noise in the cross-covariance between species that occurs when species are weakly chemically related at the same location. These errors need to be filtered out in addition to a

  16. The Development and Application of an Integrated VAR Process Model

    Science.gov (United States)

    Ballantyne, A. Stewart

    2016-07-01

    The VAR ingot has been the focus of several modelling efforts over the years with the result that the thermal regime in the ingot can be simulated quite realistically. Such models provide important insight into solidification of the ingot but present some significant challenges to the casual user such as a process engineer. To provide the process engineer with a tool to assist in the development of a melt practice, a comprehensive model of the complete VAR process has been developed. A radiation heat transfer simulation of the arc has been combined with electrode and ingot models to develop a platform which accepts typical operating variables (voltage, current, and gap) together with process parameters (electrode size, crucible size, orientation, water flow, etc.) as input data. The output consists of heat flow distributions and solidification parameters in the form of text, comma-separated value, and visual toolkit files. The resulting model has been used to examine the relationship between the assumed energy distribution in the arc and the actual energy flux which arrives at the ingot top surface. Utilizing heat balance information generated by the model, the effects of electrode-crucible orientation and arc gap have been explored with regard to the formation of ingot segregation defects.

  17. Genetic Relationships among Prunus mume var. pendula Using AFLP Markers

    Institute of Scientific and Technical Information of China (English)

    Ming Jun; Zhang Qixiang; Ru Guangxin; Mao Qingshan; Yan Xiaolan; Lan Yanping

    2003-01-01

    Genetic relationships among Prunus mume var. pendula were studied by using AFLP markers. 18 accessions representing 14 cultivars ofPrunus murne var. pendula were selected from the germplasm collection at the Research Center of China Mci Flower. Seven Mse I-EcoR I AFLP primer combinations revealed 450 legible bands, and 269 of which were polymorphic markers. A similarity matrix was prepared using the simple matching coefficient of similarity and Nei's (72) distance coefficient. A UPGMA dendrogram demonstrated the genetic relationships of the cultivars. The information given by AFLP markers was basically consistent with the morphological classification and the evolutionary history of the morphotypes, and roughly supported the new revised classification system for Chinese Mci Cultivars. But there were still several exceptions: 1) the 'Guhong Chuizhi' inserted between the 'Tiaoxue Chuizhi' and the 'Danfen Chuizhi'; 2) the 'Wufu Chuizhi' kept off the Pink Pendant Form, and the 'Moshan Chuizhi' was removed from Viridiflora Pendant Form; 3) the 'Danbi Chuizhi' and the 'Shuangbi Chuizhi' of Viridiflora Pendant Form got together well but fell within the Pink Pendant Form.

  18. Molecular structures of fructans from Agave tequilana Weber var. azul.

    Science.gov (United States)

    Lopez, Mercedes G; Mancilla-Margalli, Norma A; Mendoza-Diaz, Guillermo

    2003-12-31

    Agave plants utilize crassulacean acid metabolism (CAM) for CO(2) fixation. Fructans are the principal photosynthetic products generated by agave plants. These carbohydrates are fructose-bound polymers frequently with a single glucose moiety. Agave tequilana Weber var. azul is an economically important CAM species not only because it is the sole plant allowed for tequila production but because it is a potential source of prebiotics. Because of the large amounts of carbohydrates in A. tequilana, in this study the molecular structures of its fructans were determined by fructan derivatization for linkage analysis coupled with gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), and matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS). Fructans were extracted from 8-year-old A. tequilana plants. The linkage types present in fructans from A. tequilana were determined by permethylation followed by reductive cleavage, acetylation, and finally GC-MS analysis. Analysis of the degree of polymerization (DP) estimated by (1)H NMR integration and (13)C NMR and confirmed by MALDI-TOF-MS showed a wide DP ranging from 3 to 29 units. All of the analyses performed demonstrated that fructans from A. tequilana consist of a complex mixture of fructooligosaccharides containing principally beta(2 --> 1) linkages, but also beta(2 --> 6) and branch moieties were observed. Finally, it can be stated that fructans from A. tequilana Weber var. azul are not an inulin type as previously thought.

  19. Phyllactinia mali and Podosphaera tridactyla var. tridactyla – new hosts of Ampelomyces quisqualis

    Directory of Open Access Journals (Sweden)

    Beata Czerniawska

    2014-08-01

    Full Text Available In 2002, the occurrence of fungi of the order Erysiphales on plants of the Słowiański Park located in Goorzów Wielkopolski was investigated. Plant samples were collected once a month, from August to November. The samples examined were above ground plant parts colonized by powdery mildew fungi. A total of 78 samples were collected. Apart from 14 species of the order Erysiphales, Ampelomyces quisqualis parasitizing on Erysiphe cichoracearum var. cichoracearum, Phyllactinia mali and Podosphaera tridactyl var. tridactyla was found. Ampelomyces quisqualis affected hyphae, oidia, and young cleistothecia of P. mali. In contrast, in E. cichoracearum var. cichoracearum, Po. tridactyle var. tridactyla, this hyperparasite colonized only hyphae and oidia. This paper for the first trime informs of A. quisqualis parasitizing on P. mali and Po. tridactyla var. tridactyla.

  20. Empirical analysis on future-cash arbitrage risk with portfolio VaR

    Science.gov (United States)

    Chen, Rongda; Li, Cong; Wang, Weijin; Wang, Ze

    2014-03-01

    This paper constructs the positive arbitrage position by alternating the spot index with Chinese Exchange Traded Fund (ETF) portfolio and estimating the arbitrage-free interval of futures with the latest trade data. Then, an improved Delta-normal method was used, which replaces the simple linear correlation coefficient with tail dependence correlation coefficient, to measure VaR (Value-at-risk) of the arbitrage position. Analysis of VaR implies that the risk of future-cash arbitrage is less than that of investing completely in either futures or spot market. Then according to the compositional VaR and the marginal VaR, we should increase the futures position and decrease the spot position appropriately to minimize the VaR, which can minimize risk subject to certain revenues.

  1. Characterization of a Peruvian isolate of Metarhizium anisopliae var. acridum, a pathogen of grasshoppers

    Directory of Open Access Journals (Sweden)

    Magalhães Bonifácio Peixoto

    2003-01-01

    Full Text Available The objective of this study was to characterize the Peruvian isolate of Metarhizium anisopliae var. acridum, CG 863, obtained from the grasshopper Schistocerca interrita, a crop pest in Peru. The characterization was done by comparing this isolate with two other ones of M. anisopliae var. acridum, from Brazil and Australia, and with an isolate of M. anisopliae var. anisopliae. The three M. anisopliae var. acridum isolates had similar growth profiles in agar plates at 25°C and 37°C, and similar RAPD patterns according to the analysis of three primers. However, regarding these parameters and conidial size, these isolates were very distinct when compared to M. anisopliae var. anisopliae isolate. Bioassays indicated that the Peruvian isolate is as pathogenic as the Brazilian isolate against nymphs of Rhammatocerus schistocercoides.

  2. MODEL NON LINIER GARCH (NGARCH UNTUK MENGESTIMASI NILAI VALUE at RISK (VaR PADA IHSG

    Directory of Open Access Journals (Sweden)

    I KOMANG TRY BAYU MAHENDRA

    2015-06-01

    Full Text Available In investment, risk measurement is important. One of risk measure is Value at Risk (VaR. There are many methods that can be used to estimate risk based on VaR framework. One of them Non Linier GARCH (NGARCH model. In this research, determination of VaR used NGARCH model. NGARCH model allowed for asymetric behaviour in the volatility such that “good news” or positive return and “bad news” or negative return. Based on calculations of VaR, the higher of the confidence level and the longer the investment period, the risk was greater. Determination of VaR using NGARCH model was less than GARCH model.

  3. Antigenic cartography of H9N2 virus and its impact on the vaccine efficacy in chickens

    Science.gov (United States)

    The H9 subtype of avian influenza virus (AIV) is wide-spread in Asia and the Middle East. The efficacy of vaccines is enhanced by the antigenic match of the hemagglutinin protein (HA) between the vaccine and the field strain. To determine how antigenic variations affect the vaccine efficacy, speci...

  4. Trypanosome Surface Antigen Genes: Analysis Using Recombinant DNA.

    Science.gov (United States)

    1984-06-15

    different VATs. These cDNAs were used to screen the genomic libraries . The cloned probes were examined by nucleotide sequence analysis and used to...examination of the consequence of - antigenic variation on the structure of the 1.1, 1.D and 1.11 VSG -, gene sequences. In addition, all genomic libraries have...immunoprecipitated by heterologous VAt specific antisera (preprint 2, figure 3; preprint 3, figure 1). These data presented in preprints 2 and Genomic

  5. Comparison of the specificity of antibodies to VAR2CSA in Cameroonian multigravidae with and without placental malaria

    DEFF Research Database (Denmark)

    Babakhanyan, Anna; Fang, Rui; Wey, Andrew;

    2015-01-01

    BACKGROUND: Antibodies (Ab) to VAR2CSA prevent Plasmodium falciparum-infected erythrocytes from sequestrating in the placenta, i.e., prevent placental malaria (PM). The specificity of Ab to VAR2CSA associated with absence of PM is unknown. Accordingly, differences in the specificity of Ab to VAR2...

  6. Agronomic Trait Variations and Ploidy Differentiation of Kiwiberries in Northwest China: Implication for Breeding

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2017-05-01

    Full Text Available Polyploid plants often have higher biomass and superior crop qualities. Breeders therefore search for crop germplasm with higher ploidy levels; however, whether higher ploidy levels are associated with better performance remains unclear. Actinidia arguta and related species, whose commercialized fruit are referred to as kiwiberries, harbor a series of ploidy races in nature, offering an opportunity to determine the link between ploidy levels and agronomic traits. In the present study, we determined the ploidy levels of A. arguta var. arguta, A. arguta var. giraldii, and A. melanandra in 16 natural populations using flow cytometry, and examined 31 trait variations in fruits, leaves and flowers by field observations, microscopic examination and laboratory analyses. Our results showed that octaploid and decaploid A. arguta var. giraldii had larger dimension of leaves than tetraploid A. arguta var. arguta and A. melanandra, but their fruits were significantly smaller. In addition, A. arguta var. giraldii (8x and 10x had higher contents of nutrients such as ascorbic acid and amino acids; however, some important agronomic traits, including the content of total sugar and total acid, were significantly lower in the octaploids and decaploids. Moreover, octaploids and decaploids did not result in greater ecological adaptability for the challenging environments and climates. In conclusion, the differentiation of ecological adaptability and traits among natural kiwiberries' cytotypes suggested that higher ploidy levels are not inevitably advantageous in plants. The findings of A. arguta and related taxa in geographical distribution and agronomic trait variations will facilitate their germplasm domestication.

  7. Toward a network model of MHC class II-restricted antigen processing

    Directory of Open Access Journals (Sweden)

    Laurence C Eisenlohr

    2013-12-01

    Full Text Available The standard model of Major Histocompatibility Complex class II (MHCII-restricted antigen processing depicts a straightforward, linear pathway: Internalized antigens are converted into peptides that load in a chaperone dependent manner onto nascent MHCII in the late endosome, the complexes subsequently trafficking to the cell surface for recognition by CD4+ T cells (TCD4+. Several variations on this theme, both moderate and radical, have come to light but these alternatives have remained peripheral, the conventional pathway generally presumed to be the primary driver of TCD4+ responses. Here we continue to press for the conceptual repositioning of these alternatives toward the center while proposing that MHCII processing be thought of less in terms of discrete pathways and more in terms of a network whose major and minor conduits are variable depending upon many factors, including the epitope, the nature of the antigen, the source of the antigen, and the identity of the antigen-presenting cell.

  8. Variability of chemical composition and antioxidant activity of essential oils between Myrtus communis var. Leucocarpa DC and var. Melanocarpa DC.

    Science.gov (United States)

    Petretto, Giacomo Luigi; Maldini, Mariateresa; Addis, Roberta; Chessa, Mario; Foddai, Marzia; Rourke, Jonathan P; Pintore, Giorgio

    2016-04-15

    Essential oils (EOs) from several individuals of Myrtus communis L. (M. communis) growing in different habitats in Sardinia have been studied. The analyses were focused on four groups of samples, namely cultivated and wild M. communis var. melanocarpa DC, characterized by red/purple berries, and cultivated and wild M. communis var. leucocarpa DC, characterized by white berries. Qualitative and quantitative analyses demonstrated different EO fingerprints among the studied samples: cultivated and wild leucocarpa variety differs mainly from the melanocarpa variety by a high amount of myrtenyl acetate (>200 mg/mL and 0.4 mg/mL in leucocarpa and melanocarpa varieties respectively). Conversely, the wild group is characterized by a higher amount, compared with the cultivated species, of linalool (about 110 mg/mL and 20 mg/mL respectively), linalyl acetate (about 24 mg/mL and about 6 mg/mL respectively) whereas EOs of the cultivated plants were rich in pinocarveol-cis compared with wild plants (about 2 mg/mL and about 0.5 mg/mL respectively). Principal component analysis applied to the chromatographic data confirm a differentiation and classification of EOs from the four groups of M. communis plants. Finally, antioxidant activity of the studied EOs shows differences between the various categories of samples.

  9. No significant difference in antigenicity or tissue transglutaminase substrate specificity of Irish and US wheat gliadins.

    Science.gov (United States)

    Keaveny, A P; Offner, G D; Bootle, E; Nunes, D P

    2000-04-01

    The prevalence of clinical celiac disease has been shown to vary both across time and between genetically similar populations. Differences in wheat antigenicity and transglutaminase substrate properties are a possible explanation for these differences. This study assessed the antigenicity and transglutaminase substrate specificities of gliadins from regions of high and low celiac disease prevalence. Gliadin was extracted from three commercial US wheat sources and two Irish sources. SDS-PAGE and western blotting revealed minor, but significant variations in the gliadin extracts. However, ELISA showed no difference in the antigenicity of these gliadins. Transglutaminase pretreatment of gliadin resulted in no significant change in gliadin antigenicity and kinetic studies showed that the Kms of the various gliadins were very similar. Purified IgA and IgG had no effect on transglutaminase activity. In summary, minor variations in wheat gliadins are unlikely to explain the observed differences in disease expression across genetically similar populations.

  10. Antimicrobial activity and chemical composition of the essential oils of Thymbra spicata var. intricata

    Directory of Open Access Journals (Sweden)

    Sarac Nurdan

    2009-01-01

    Full Text Available In this study, T. spicata var. intricata , endemic to Turkey, were collected from various localities of Mugla, Turkey. The essential oils were obtained using the hydrodistillation method. The antimicrobial activities of the essential oils on micro-organisms, including multiple antibiotic resistant bacteria, were evaluated using the disc diffusion method. The chemical composition of the essential oil was determined by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS. The essential oils were effective against Gram-positive and Gram-negative bacteria, which included multiple antibiotic resistant strains. However, Pseudomonas aeruginosa ATCC 27853 and Pseudomonas fluorescens MU 87 were resistant to these oils. The essential oils were very effective against Candida albicans . The antimicrobial activity of the essential oils showed some variations depending on the localities from which they were collected. A total 24 components were identified in the essential oil. The main components were characterized as carvacrol (75.74%, γ-terpinene (9.28%, p -cymene (7.17%, myrcene (1.39%, β-caryophyllene (1.13% and thymol (0.15%, respectively.

  11. Growth and N2 fixation in an Alnus hirsuta (Turcz.) var. sibirica stand in Japan

    Indian Academy of Sciences (India)

    Hiroyuki Tobita; Shigeaki F Hasegawa; Kenichi Yazaki; Masabumi Komatsu; Mitsutoshi Kitao

    2013-11-01

    To estimate the N2 fixation ability of the alder (Alnus hirsuta (Turcz.) var. sibirica), we examined the seasonal variation in nitrogenase activity of nodules using the acetylene reduction method in an 18-year-old stand naturally regenerated after disturbance by road construction in Japan. To evaluate the contribution of N2 fixation to the nitrogen (N) economy in this alder stand, we also measured the phenology of the alder, the litterfall, the decomposition rate of the leaf litter, and N accumulation in the soil. The acetylene reduction activity per unit nodule mass (ARA) under field conditions appeared after bud break, peaked the maximum in midsummer after full expansion of the leaves, and disappeared after all leaves had fallen. There was no consistent correlation between ARA and tree size (dbh). The amount of N2 fixed in this alder stand was estimated at 56.4 kg ha−1 year−1 when a theoretical molar ratio of 3 was used to convert the amount of reduced acetylene to the amount of fixed N2. This amount of N2 fixation corresponded to the 66.4% of N in the leaf litter produced in a year. These results suggested that N2 fixation still contributed to the large portion of N economy in this alder stand.

  12. Application of a static VAR compensator to an autonomous wind-diesel system

    Energy Technology Data Exchange (ETDEWEB)

    Tomilson, A.; Quaicoe, J.; Gosine, R.; Hinchey, M.; Bose, N. [Memorial University of Newfoundland, St. John' s (Canada). Faculty of Engineering and Applied Science

    1998-07-01

    High-penetration, no-storage wind-diesel (HPNSWD) systems are subjected to large, rapid power variations that can cause unacceptable voltage fluctuations. This paper outlines a comprehensive dynamic model of a HPNSWD system which uses a static VAR compensator (SVC) to reduce these voltage fluctuations to an acceptable level. The model is based on the wind-diesel test-bed at the Atlantic Wind Test Site in PEI, Canada, and was developed in the MATLAB-SIMULINK dynamic system simulation software. The principal function of the SVC is to compensate the wind turbine's reactive power. The SVC also has a novel voltage control loop which enables it to respond to fast voltage transients while allowing the diesel's synchronous generator to retain primary voltage control. Results from the simulation of the HPNSWD system with and without the SVC are compared in this paper to demonstrate the effectiveness of the SVC in improving the system's voltage stability.

  13. Improvement of Salt Tolerance in Trigonella foenum-graecum L. var. PEB by Plant Growth Regulators

    Directory of Open Access Journals (Sweden)

    Anjali Ratnakar

    2014-05-01

    Full Text Available The crop yield is reduced under saline conditions and this hampers agricultural productivity. The incorporation of plant growth regulators (PGRs during presoaking treatments in many crops has improved seed performance under saline conditions. In order to study the ameliorative effect of plant growth regulators, experiments were conducted to study the variation in organic constituents in the leaves of Trigonella foenum-graecum L. var.PEB, where the seeds were primed with different plant growth regulators and grown under NaCl salinity. After a pre-soaking treatment of six hours in 20 mg L-1 solutions of gibberllic acid (GA3, 6-furfuryladenine (Kinetin and benzyl adenine (BA, the seeds were allowed to germinate and grow for forty-five days under saline conditions. On the analysis of mature leaves, it was observed that chlorophyll a and b, total chlorophyll and protein showed an increase in PGR-treated plants compared to the untreated set. The accumulation of the stress metabolite such as proline and sugars, which increase under saline conditions, showed a significant decrease in the plants pretreated with PGRs.

  14. Demographic Genetic Structure of Cryptomeria japonica var.sinensis in Tianmushan Nature Reserve,China

    Institute of Scientific and Technical Information of China (English)

    Yan Chen; Shu-Zhen Yang; Ming-Shui Zhao; Bi-Ye Ni; Liang Liu; Xiao-Yong Chen

    2008-01-01

    Genetic changes over space and time provide insights into the relative roles of evolutionary factors in shaping genetic patterns within plant populations.However,compared with spatial genetic structure,few studies have been conducted on genetic changes over time.In this study,we used six polymorphic microsatellite loci to assess genetic variation of six size-classes of the population of Liushan,Cryptomeria japonica var.sinensis,in the Tianmushan National Nature Reserve,whose origin was debatable.The mean number of alleles per locus and expected heterozygosity were 4.583 and 0.5999 respectively,lower than other conifers with the same life history characteristics.FST was 0.002 4- 0.003,and the pairwise test revealed no significant differentiation in any pair of size classes.Significant heterozygosity excesses were detected in five size classes except the oldest one,indicating bottleneck event(s).The above results support the hypothesis that Tianmushan population was introduced and followed by natural regeneration.

  15. Identification of housekeeping genes suitable for gene expression analysis in Jian carp (Cyprinus carpio var. jian).

    Science.gov (United States)

    Tang, Yong-kai; Yu, Ju-hua; Xu, Pao; Li, Jian-lin; Li, Hong-xia; Ren, Hong-tao

    2012-10-01

    Jian carp (Cyprinus carpio var. jian) is an important economic fish species cultured in China. In this report, we performed a systematic analysis to identify an appropriate housekeeping (HK) gene for the study of gene expression in Jian carp. For this purpose, partial DNA sequences of four potential candidate genes (elongation factor 1 alpha (EF-1α), glyceraldehyde-3-phosphate (GAPDH), beta-actin (ACTB), and 18S ribosomal RNA (18S rRNA) were isolated, and their expression levels were studied using RNA extracted from nine tissues (forebrain, hypothalamus, liver, fore-intestine, hind-intestine, ovary, muscle, heart, kidney) in juvenile and adult Jian carp. Gene expression levels were quantified by quantitative real time RT-PCR (qRT-PCR), and expression stability was evaluated by comparing the coefficients of variation (CV) of the Ct values. The results showed that EF-1α was the most suitable HK gene in all tissues of juvenile and adult Jian carp. However, at distinct juvenile and adult developmental stages, there was not a single optimal gene for normalization of expression levels in all tissues. EF-1α was the most stable gene only in forebrain, hypothalamus, liver, heart, and kidney. These results provide data that can be expected to aid gene expression analysis in Jian carp research, but underline the importance of identifying the optimal HK gene for each new experimental paradigm.

  16. A 4D-Var inversion system based on the icosahedral grid model (NICAM-TM 4D-Var v1.0) - Part 2: Optimization scheme and identical twin experiment of atmospheric CO2 inversion

    Science.gov (United States)

    Niwa, Yosuke; Fujii, Yosuke; Sawa, Yousuke; Iida, Yosuke; Ito, Akihiko; Satoh, Masaki; Imasu, Ryoichi; Tsuboi, Kazuhiro; Matsueda, Hidekazu; Saigusa, Nobuko

    2017-06-01

    A four-dimensional variational method (4D-Var) is a popular technique for source/sink inversions of atmospheric constituents, but it is not without problems. Using an icosahedral grid transport model and the 4D-Var method, a new atmospheric greenhouse gas (GHG) inversion system has been developed. The system combines offline forward and adjoint models with a quasi-Newton optimization scheme. The new approach is then used to conduct identical twin experiments to investigate optimal system settings for an atmospheric CO2 inversion problem, and to demonstrate the validity of the new inversion system. In this paper, the inversion problem is simplified by assuming the prior flux errors to be reasonably well known and by designing the prior error correlations with a simple function as a first step. It is found that a system of forward and adjoint models with smaller model errors but with nonlinearity has comparable optimization performance to that of another system that conserves linearity with an exact adjoint relationship. Furthermore, the effectiveness of the prior error correlations is demonstrated, as the global error is reduced by about 15 % by adding prior error correlations that are simply designed when 65 weekly flask sampling observations at ground-based stations are used. With the optimal setting, the new inversion system successfully reproduces the spatiotemporal variations of the surface fluxes, from regional (such as biomass burning) to global scales. The optimization algorithm introduced in the new system does not require decomposition of a matrix that establishes the correlation among the prior flux errors. This enables us to design the prior error covariance matrix more freely.

  17. A 4D-Var inversion system based on the icosahedral grid model (NICAM-TM 4D-Var v1.0 – Part 2: Optimization scheme and identical twin experiment of atmospheric CO2 inversion

    Directory of Open Access Journals (Sweden)

    Y. Niwa

    2017-06-01

    Full Text Available A four-dimensional variational method (4D-Var is a popular technique for source/sink inversions of atmospheric constituents, but it is not without problems. Using an icosahedral grid transport model and the 4D-Var method, a new atmospheric greenhouse gas (GHG inversion system has been developed. The system combines offline forward and adjoint models with a quasi-Newton optimization scheme. The new approach is then used to conduct identical twin experiments to investigate optimal system settings for an atmospheric CO2 inversion problem, and to demonstrate the validity of the new inversion system. In this paper, the inversion problem is simplified by assuming the prior flux errors to be reasonably well known and by designing the prior error correlations with a simple function as a first step. It is found that a system of forward and adjoint models with smaller model errors but with nonlinearity has comparable optimization performance to that of another system that conserves linearity with an exact adjoint relationship. Furthermore, the effectiveness of the prior error correlations is demonstrated, as the global error is reduced by about 15 % by adding prior error correlations that are simply designed when 65 weekly flask sampling observations at ground-based stations are used. With the optimal setting, the new inversion system successfully reproduces the spatiotemporal variations of the surface fluxes, from regional (such as biomass burning to global scales. The optimization algorithm introduced in the new system does not require decomposition of a matrix that establishes the correlation among the prior flux errors. This enables us to design the prior error covariance matrix more freely.

  18. Isolation and characterization of 21 microsatellite loci in Cardiocrinum giganteum var. yunnanense (Liliaceae), an important economic plant in China.

    Science.gov (United States)

    Li, Rong; Yang, Jie; Yang, Junbo; Dao, Zhiling

    2012-01-01

    Twenty-one microsatellite markers from the genome of Cardiocrinum giganteum var. yunnanense, an important economic plant in China, were developed with a fast isolation protocol by amplified fragment length polymorphism of sequences containing repeats (FIASCO). Polymorphism within each locus was assessed in 24 wild individuals from Gaoligong Mountains in western Yunnan Province, China. The number of alleles per locus ranged from 2 to 4 with a mean of 2.9. The expected and observed levels of heterozygosity ranged from 0.042 to 0.726 and from 0.000 to 1.000, with averages of 0.44 and 0.31, respectively. These polymorphic microsatellite markers should prove useful in population genetics studies and assessments of genetic variation to develop conservation and management strategies for this species.

  19. A hybrid PSO technique for procuring VAR ancillary service in the deregulated electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    El-Araby, E.E. [Department of Electrical Engineering, Suez Canal University (Egypt); Yorino, Naoto [Department of Artificial Complex Systems Engineering, Hiroshima University (Japan)

    2010-07-15

    This paper develops a new market-based technique for acquiring VAR ancillary service in the electricity market. The main objective of the developed market is to enable transmission operator ''TO'' to procure VAR service in a long term contract from the critical VAR providers that satisfy minimum VAR service payment while maintaining system security. Reactive power control problem for voltage stability is introduced into the VAR market problem in an explicit manner for normal and emergency states. An integration of particle swarm optimization ''PSO'' is presented with successive linear programming ''SLP'' for dealing with the VAR ancillary service problem. The problem is formulated as a large-scale nonlinear constrained optimization problem with a non-differentiable objective function representing VAR payment and operational costs. This type of problem is hard to be treated straightforwardly by the classical optimization methods. Therefore, we propose here a two-layer hybrid PSO/SLP approach, which is suited for carrying out the difficulties associated with non-differentiable and discontinuous objective functions. The proposed method has been examined on the standard IEEE 57 bus-system and compared with GA/SLP method to demonstrate its capability. (author)

  20. Phosphorylation of SU(VAR3-9 by the chromosomal kinase JIL-1.

    Directory of Open Access Journals (Sweden)

    Joern Boeke

    Full Text Available The histone methyltransferase SU(VAR3-9 plays an important role in the formation of heterochromatin within the eukaryotic nucleus. Several studies have shown that the formation of condensed chromatin is highly regulated during development, suggesting that SU(VAR3-9's activity is regulated as well. However, no mechanism by which this may be achieved has been reported so far. As we and others had shown previously that the N-terminus of SU(VAR3-9 plays an important role for its activity, we purified interaction partners from Drosophila embryo nuclear extract using as bait a GST fusion protein containing the SU(VAR3-9 N-terminus. Among several other proteins known to bind Su(VAR3-9 we isolated the chromosomal kinase JIL-1 as a strong interactor. We show that SU(VAR3-9 is a substrate for JIL-1 in vitro as well as in vivo and map the site of phosphorylation. These findings may provide a molecular explanation for the observed genetic interaction between SU(VAR3-9 and JIL-1.

  1. VAR Analysis of the Monetary Transmission Mechanism in Kyrgyzstan

    Directory of Open Access Journals (Sweden)

    Nurlan ATABAEV

    2013-05-01

    Full Text Available This article examines the effects of monetary transmission on real output and price level in Kyrgyzstan which is very important issue for central banks. We analyzed the relationships between the money supply, real output, price level, interest rate, credit and real exchange rate by using the vector autoregression approach (VAR and monthly data for 2003-2011. As a result the interest rate channel remains weak, on the other hand it have been revealed that the credit channel has some affects to real output, the exchange rate channel affects the prices. Exchange rate channel remains still the most effective channel. Based on these results, it can be argued that government can use credit and interest rate channel in increasing real output, and the exchange rate channel in achieving price stability in Kyrgyzstan.

  2. Tillers induction in Bactris gasipaes var. gasipaes seedlings

    Directory of Open Access Journals (Sweden)

    Ernani Augusto Ochekoski Mossanek

    2014-04-01

    Full Text Available Bactris gasipaes produces heart-of-palm. Peach palm is a perennial crop that has a tillering capacity, being an alternative to illegal extraction. There is a lack of studies about vegetative propagation technics for this species. The present study aimed to analyze different tillering induction methods in Bactris gasipaes var. gasipaes seedlings in four different seasons. The treatments were: 1 stem bending; 2 stem bending and application of 150 mg kg-1 of benzylaminopurine; 3 stem bending and application of 150 mg kg-1 of gibberellic acid and; 4 stem girdling. The experimental design was random with 4 replicates of 20 plants per treatment. Anatomical analyses were conducted at the stem, and the tillering and mortality of the treated plants were evaluated. It was possible to identify the stem tissues and the meristematic apex site by anatomical analysis. The stem bending treatments were inefficient; but girdling presented potential as tillers inducer.

  3. Forecasting Macedonian Business Cycle Turning Points Using Qual Var Model

    Directory of Open Access Journals (Sweden)

    Petrovska Magdalena

    2016-09-01

    Full Text Available This paper aims at assessing the usefulness of leading indicators in business cycle research and forecast. Initially we test the predictive power of the economic sentiment indicator (ESI within a static probit model as a leading indicator, commonly perceived to be able to provide a reliable summary of the current economic conditions. We further proceed analyzing how well an extended set of indicators performs in forecasting turning points of the Macedonian business cycle by employing the Qual VAR approach of Dueker (2005. In continuation, we evaluate the quality of the selected indicators in pseudo-out-of-sample context. The results show that the use of survey-based indicators as a complement to macroeconomic data work satisfactory well in capturing the business cycle developments in Macedonia.

  4. Chromosome doubling in Paspalum notatum var. saure (cultivar Pensacola

    Directory of Open Access Journals (Sweden)

    Luis Weiler

    2015-04-01

    Full Text Available Paspalum notatum is one of the most important native grassland species of southern Brazil, and the main forage source for livestock. The native ecotypes are tetraploid and have apomictic reproduction, which prevents the registration and protection of plant varieties. However, the cultivated variety Paspalum notatum var. saurae (cultivar Pensacola is diploid and sexual. The objective of this study was to artificially produce polyploid cv. Pensacola plants, to be used as female parents in crosses with male tetraploid and apomictic parents. Seedlings and seeds were immersed in colchicine solutions for different periods. A tetraploid chromosome number was confirmed in three plants. The reproduction mode of the resulting polyploid plants will be assessed; if confirmed to be sexual, they can be used in crosses with native apomictic plants to breed new intraspecific hybrids.

  5. Citogenética de Guazuma ulmifolia var. Ulmifolia (Sterculiaceae

    Directory of Open Access Journals (Sweden)

    Fernando Tapia-Pastrana

    2007-01-01

    Full Text Available Se utilizó una metodología de extendido en superficie y secado al aire para obtener por vez primera el cariotipo somático de una población de Guazuma ulmifolia var. ulmifolia. El número cromosómico diploide 2n = 16 obtenido a partir de meristemos radiculares confirma recuentos anteriores. La fórmula cariotípica fue 14m + 2st con una ligera asimetría (T.F.% = 42,19. La longitud cromosómica total haploide fue de 11,65 µm con un intervalo cromosómico de 1,11 - 2,05 µm. Los organizadores nucleolares asociados a constricciones secundarias ubicados en el par 3 (m y el polimorfismo que exhibe el par 8 (st pueden ser empleados como marcadores citogenéticos en futuros estudios de otras especies y variedades del género.

  6. Hot air convective dehydration characteristics of Daucus carota var. Nantes

    Directory of Open Access Journals (Sweden)

    Raees-ul Haq

    2015-12-01

    Full Text Available The present work focuses on experimental and theoretical study of air dehydration kinetics of Daucus carota var. Nantes in laboratory scale drying chamber. Steam blanching as a pretreatment was applied prior to dehydration of shreds and the results indicated a gradual decrease in drying time from 2.9 to 5.5% in temperature range of 50–70°C, for steam blanched samples in comparison to untreated carrots. Four different mathematical drying models (Newton, Page, Modified Page and Henderson and Pabis were evaluated for goodness of fit by comparing their respective R2, χ2, and RMSE parameters. Comparison of the statistical parameters led to conclusion that Page model showed a better quality of fit and presents dehydration characteristics in better way to obtain drying curves than any other model.

  7. Controlling pool depth during VAR of Alloy 718

    Science.gov (United States)

    Lopez, F.; Beaman, J.; Williamson, R.; Evans, D.

    2016-07-01

    A longtime goal of superalloy producers has been to control the geometry of the liquid pool in solidifying ingots. Accurate pool depth control at appropriate values is expected to result in ingots free of segregation defects. This article describes an industrial VAR experiment in which a 430mm (17 in) diameter Alloy 718 electrode was melted into a 510mm (20 in) ingot. In the experiment, the depth of the liquid pool at the mid-radius was controlled to three different set-points: 137 mm (nominal), 193 mm (deep) and 118 mm (shallow). At each level, the pool depth was marked by a power cutback of several minutes. The ingot was sectioned and longitudinal slices were cut out. Analysis of the photographed ingot revealed that accurate control was obtained for both the nominal and deep pool cases, while the third one was not conclusive.

  8. Corruption Effects on Nigeria: Aggregate and Sectoral Estimates Using VAR

    Directory of Open Access Journals (Sweden)

    Raymond Osi Alenoghena

    2015-06-01

    Full Text Available This research study investigates the impact of corruption on some key activity sectors of the Nigerian economy between 1996 and 2013 using VAR technique. The empirical estimates demonstrate that corruption affects most significantly agriculture, services, wholesale and retail sectors in Nigeria. As well, the study shows that the control of corruption has significant effect in the reduction of corruption. The study recommends that Nigeria can use an amalgamation of ethics hotlines for reporting corruption, open-door policies to embolden subordinates to consult with bosses for guidance, a “zero-tolerance” policy for breaches, anticorruption training sessions, and complete transparency in governmental operations to minimalize infractions. Nigeria will require strong political will and vision, credibility, frontal assault, new staff, deregulation, unconventional methods, close coordination, harnessing technology and tailoring international experience to local conditions.

  9. ent-Kaurane Diterpenoids from Isodon eriocalyx var. laxiflorat

    Institute of Scientific and Technical Information of China (English)

    汪伟光; 吴海燕; 杜雪; 晋建新; 孙汉董

    2012-01-01

    Four new ent-kaurane diterpenoids, 6fl,13ct,15fl-trihydroxy-16-ene-3a,20-epoxy-ent-kaur- 1,7-dione (1), 6-hydroxy-3a,20-epoxy-5(6)-ene-ent-kaur-l,7,15-trione (2), 6-hydroxy-15fl-acetoxy-3a,20-epoxy-16]3,17-epoxy- 5(6)-ene-ent-kaur-l,7-dione (3), 3ct,17-dihydroxy-15(16)-ene-ent-kaur-7-one (4), along with four known com- pounds 5--8 were isolated from the leaves oflsodon eriocalyx var. laxiflora. The structures were elucidated by ex- tensive spectroscopic methods (IR, UV, MS and NMR). The cytotoxic activities of these compounds were evaluated by MTT assay. Compound 8 showed moderate inhibitory effects on HL-60, SMMC-7721, MCF-7 and SW-480 cell lines.

  10. Deterioration of expanded polystyrene caused by Aureobasidium pullulans var. melanogenum.

    Science.gov (United States)

    Castiglia, Valeria C; Kuhar, Francisco

    2015-01-01

    An expanded-polystyrene factory located in northern Buenos Aires reported unusual dark spots causing esthetic damage in their production. A fungal strain forming black-olive colonies on extract malt agar medium was isolated from the damaged material and identified as Aureobasidium pullullans var. melanogenum. This fungus is particularly known for its capacity to produce hydrolytic enzymes and a biodegradable extracellular polysaccharide known as pullulan, which is used in the manufacture of packaging material for food and medicine. Laboratory tests were conducted to characterize its growth parameters. It was found that the organism was resistant to a wide range of pHs but did not survive at temperatures over 65°C. The proposed action plan includes drying of the material prior to packaging and disinfection of the machinery used in the manufacturing process and of the silos used for raw material storage.

  11. Subsynchronous torsional interactions with static VAR compensators; Influence of HVDC

    Energy Technology Data Exchange (ETDEWEB)

    Rostamkolai, N.; Piwko, R.J.; Larsen, E.V. (General Electric Co., Schenectady, NY (USA)); Fisher, D.A. (New England Power Service Co., Westborough, MA (USA)); Mobarak, M.A. (New Brunswick Electric Power Commission, Fredericton, NB (Canada)); Poitras, A.E. (Maine Electric Power Co., Augusta, ME (US))

    1991-02-01

    Planning for installation of a static var compensator (SVC) in Chester, Maine, was initiated in 1987. The pre-specification subsynchronous torsional interaction (SSTI) studies showed the SVC might have a negative influence on stability of torsional modes of vibration of the nearby turbine-generators. In a previous paper, the parameters influencing the level of SSTI were identified with the use of a simple system. This paper extends the work to power systems containing an HVDC transmission system. The combined effect of SVC and HVDC on turbine-generator SSTI is investigated with the use of a hypothetical system. Simulation plots for the large machines of New Brunswick and Maine are included to quantify the level of interaction with the Chester SVC. Filtering as a mitigation measure is proposed to eliminate the small level of SSTI attributed to the Chester SVC.

  12. Analysis of the Complete Chloroplast Genome of a Medicinal Plant, Dianthus superbus var. longicalyncinus, from a Comparative Genomics Perspective.

    Directory of Open Access Journals (Sweden)

    Gurusamy Raman

    Full Text Available Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicinal plant that is also used for ornamental purposes. In this study, D. superbus was compared to its closely related family of Caryophyllaceae chloroplast (cp genomes such as Lychnis chalcedonica and Spinacia oleracea. D. superbus had the longest large single copy (LSC region (82,805 bp, with some variations in the inverted repeat region A (IRA/LSC regions. The IRs underwent both expansion and constriction during evolution of the Caryophyllaceae family; however, intense variations were not identified. The pseudogene ribosomal protein subunit S19 (rps19 was identified at the IRA/LSC junction, but was not present in the cp genome of other Caryophyllaceae family members. The translation initiation factor IF-1 (infA and ribosomal protein subunit L23 (rpl23 genes were absent from the Dianthus cp genome. When the cp genome of Dianthus was compared with 31 other angiosperm lineages, the infA gene was found to have been lost in most members of rosids, solanales of asterids and Lychnis of Caryophyllales, whereas rpl23 gene loss or pseudogization had occurred exclusively in Caryophyllales. Nevertheless, the cp genome of Dianthus and Spinacia has two introns in the proteolytic subunit of ATP-dependent protease (clpP gene, but Lychnis has lost introns from the clpP gene. Furthermore, phylogenetic analysis of individual protein-coding genes infA and rpl23 revealed that gene loss or pseudogenization occurred independently in the cp genome of Dianthus. Molecular phylogenetic analysis also demonstrated a sister relationship between Dianthus and Lychnis based on 78 protein-coding sequences. The results presented herein will contribute to studies of the evolution, molecular biology and genetic engineering of the medicinal and ornamental plant, D. superbus var. longicalycinus.

  13. Analysis of the Complete Chloroplast Genome of a Medicinal Plant, Dianthus superbus var. longicalyncinus, from a Comparative Genomics Perspective.

    Science.gov (United States)

    Raman, Gurusamy; Park, SeonJoo

    2015-01-01

    Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicinal plant that is also used for ornamental purposes. In this study, D. superbus was compared to its closely related family of Caryophyllaceae chloroplast (cp) genomes such as Lychnis chalcedonica and Spinacia oleracea. D. superbus had the longest large single copy (LSC) region (82,805 bp), with some variations in the inverted repeat region A (IRA)/LSC regions. The IRs underwent both expansion and constriction during evolution of the Caryophyllaceae family; however, intense variations were not identified. The pseudogene ribosomal protein subunit S19 (rps19) was identified at the IRA/LSC junction, but was not present in the cp genome of other Caryophyllaceae family members. The translation initiation factor IF-1 (infA) and ribosomal protein subunit L23 (rpl23) genes were absent from the Dianthus cp genome. When the cp genome of Dianthus was compared with 31 other angiosperm lineages, the infA gene was found to have been lost in most members of rosids, solanales of asterids and Lychnis of Caryophyllales, whereas rpl23 gene loss or pseudogization had occurred exclusively in Caryophyllales. Nevertheless, the cp genome of Dianthus and Spinacia has two introns in the proteolytic subunit of ATP-dependent protease (clpP) gene, but Lychnis has lost introns from the clpP gene. Furthermore, phylogenetic analysis of individual protein-coding genes infA and rpl23 revealed that gene loss or pseudogenization occurred independently in the cp genome of Dianthus. Molecular phylogenetic analysis also demonstrated a sister relationship between Dianthus and Lychnis based on 78 protein-coding sequences. The results presented herein will contribute to studies of the evolution, molecular biology and genetic engineering of the medicinal and ornamental plant, D. superbus var. longicalycinus.

  14. Origin of Cryptococcus neoformans var. neoformans Diploid Strains

    Science.gov (United States)

    Cogliati, Massimo; Esposto, Maria C.; Clarke, David L.; Wickes, Brian L.; Viviani, Maria A.

    2001-01-01

    The basidiomycetous yeast Cryptococcus neoformans is an important human fungal pathogen. Two varieties, C. neoformans var. neoformans and C. neoformans var. gattii, have been identified. Both are heterothallic with two mating types, MATa and MATα. Some rare isolates are self-fertile and are considered occasional diploid or aneuploid strains. In the present study, 133 isolates, mostly from Italian patients, were investigated to detect the presence of diploid strains in the Igiene Università Milano culture collection. All of the diploid isolates were further investigated by different methods to elucidate their origins. Forty-nine diploid strains were identified by flow cytometry. PCR fingerprinting using the (GACA)4 primer showed that the diploid state was associated with two specific genotypes identified as VN3 and VN4. Determination of mating type on V8 juice medium confirmed that the majority of the strains were sterile. PCR and dot blotting using the two pheromone genes (MFa and MFα) as probes identified 36 of the 49 diploid isolates as MATa/α. The results of pheromone gene sequencing showed that two allelic MFα genes exist and are distinct for serotypes A and D. In contrast, the MFa gene sequence was conserved in both serotype alleles. Amplification of serotype-specific STE20 alleles demonstrated that the diploid strains contained one mating locus inherited from a serotype A parent and one inherited from a serotype D parent. The present results suggest that diploid isolates may be common among the C. neoformans population and that in Italy and other European countries serotype A and D populations are not genetically isolated but are able to recombine by sexual reproduction. PMID:11682503

  15. Experimental poisoning by Baccharis megapotamica var. weirii in buffalo

    Directory of Open Access Journals (Sweden)

    José C. Oliveira-Filho

    2012-05-01

    Full Text Available Five male 6-8 month-old Murrah buffalo calves were orally dosed with the fresh aerial parts of Baccharis megapotamica var. weirii at doses of 1, 3, 4, 5 and 10g/kg body weight (bw (~1-10mg macrocyclic trichothecenes/kg/bw. The B. megapotamica used for the experiment was harvested on a farm where a recent spontaneous outbreak of poisoning caused by such plant had occurred. Clinical signs appeared 4-20 hours and 4 buffaloes died 18-49 hours after the ingestion of the plant. Clinical signs were apathy, anorexia, and watery diarrhea, fever, colic, drooling, muscle tremors, restlessness, laborious breathing and ruminal atony, and dehydration. The most consistent gross findings were restricted to the gastrointestinal (GI tract consisted of varying degrees of edema and reddening of the mucosa of the forestomach. Histopathological findings consisted of varying degrees of necrosis of the epithelial lining of the forestomach and of lymphocytes within lymphoid organs and aggregates. Fibrin thrombi were consistently found in sub-mucosal vessels of the forestomach and in the lumen of hepatic sinusoids. It is suggested that dehydration, septicemia and disseminated intravascular coagulation participate in the pathogenesis of the intoxication and play a role as a cause of death. A subsample of B. megapotamica var. weirii was frozen-dried and ground and analyzed using UHPLC (Ultra High Performance Liquid Chromatography with high resolution Time of Flight mass spectrometry and tandem mass spectrometry, it was shown that the plant material contained at least 51 different macrocyclic trichothecenes at a total level of 1.1-1.2mg/g. About 15-20% of the total trichothecenes contents was found to be monosaccharide conjugates, with two thirds of these being glucose conjugates and one third constituted by six aldopentose conjugates (probably xylose, which has never been reported in the literature.

  16. Aberrant meiotic behavior in Agave tequilana Weber var. azul

    Directory of Open Access Journals (Sweden)

    Rodríguez-Garay Benjamin

    2002-10-01

    Full Text Available Abstract Background Agave tequilana Weber var. azul, is the only one variety permitted by federal law in México to be used for tequila production which is the most popular contemporary alcoholic beverage made from agave and recognized worldwide. Despite the economic, genetic, and ornamental value of the plant, it has not been subjected to detailed cytogenetic research, which could lead to a better understanding of its reproduction for future genetic improvement. The objective of this work was to study the meiotic behavior in pollen mother cells and its implications on the pollen viability in Agave tequilana Weber var. azul. Results The analysis of Pollen Mother Cells in anaphase I (A-I showed 82.56% of cells with a normal anaphase and, 17.44% with an irregular anaphase. In which 5.28% corresponded to cells with side arm bridges (SAB; 3.68% cells with one bridge and one fragment; 2.58% of irregular anaphase showed cells with one or two lagging chromosomes and 2.95% showed one acentric fragment; cells with two bridges and cells with two bridges and one acentric fragment were observed in frequencies of 1.60% and 1.35% respectively. In anaphase II some cells showed bridges and fragments too. Aberrant A-I cells had many shrunken or empty pollen grains (42.00% and 58.00 % viable pollen. Conclusion The observed meiotic irregularities suggest that structural chromosome aberrations have occurred, such as heterozygous inversions, sister chromatid exchanges, deletions and duplications which in turn are reflected in a low pollen viability.

  17. Concepts and applications for influenza antigenic cartography

    Science.gov (United States)

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2011-01-01

    Influenza antigenic cartography projects influenza antigens into a two or three dimensional map based on immunological datasets, such as hemagglutination inhibition and microneutralization assays. A robust antigenic cartography can facilitate influenza vaccine strain selection since the antigenic map can simplify data interpretation through intuitive antigenic map. However, antigenic cartography construction is not trivial due to the challenging features embedded in the immunological data, such as data incompleteness, high noises, and low reactors. To overcome these challenges, we developed a computational method, temporal Matrix Completion-Multidimensional Scaling (MC-MDS), by adapting the low rank MC concept from the movie recommendation system in Netflix and the MDS method from geographic cartography construction. The application on H3N2 and 2009 pandemic H1N1 influenza A viruses demonstrates that temporal MC-MDS is effective and efficient in constructing influenza antigenic cartography. The web sever is available at http://sysbio.cvm.msstate.edu/AntigenMap. PMID:21761589

  18. PCR-RFLP analysis of chitinase genes enables efficient genotyping of Metarhizium anisopliae var. anisopliae.

    Science.gov (United States)

    Enkerli, Jürg; Ghormade, Vandana; Oulevey, Catherine; Widmer, Franco

    2009-10-01

    A new genotyping tool has been developed and evaluated for Metarhizium anisopliae var. anisopliae. The tool is based on Restriction Fragment Length Polymorphism (RFLP) analysis of three chitinase genes that are functionally linked to insect-pathogenicity of this fungus. It allowed for discrimination of 14 genotypes among 22 M. anisopliae var. anisopliae strains of a world wide collection. Analyses revealed that the approach may also be applicable to other Metarhizium varieties. The new tool will be useful for genetic characterization of M. anisopliae var. anisopliae strains, and it is applicable for laboratories with limited access to molecular diagnostic equipment.

  19. Mimosa diversiplla var. subglabriseta (MimosoIdeae, Leguminosae, a new record for the flora of Paraguay

    Directory of Open Access Journals (Sweden)

    Javier A Luna

    2012-12-01

    Full Text Available The presence of Mimosa diversipila M. Micheli var. subglabriseta Barneby & Fortunato is now reported for first time in Paraguay. A revision of Barneby's initial description of the variety and photographs of one of the Paraguayan specimens are given in this paper.Mimosa diversipila var. subglabriseta (Mimosoideae, Leguminosae, una nueva cita para la flora de Paraguay. Reportamos por primera vez la presencia de Mimosa diversipila M. Micheli var. subglabriseta Barneby & Fortunato en Paraguay. Una revisión de la descripción inicial de Barneby y fotografías de uno de los ejemplares de Paraguay se incluyen en este documento.

  20. Return predictability and intertemporal asset allocation: Evidence from a bias-adjusted VAR model

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard

    We extend the VAR based intertemporal asset allocation approach from Campbell et al. (2003) to the case where the VAR parameter estimates are adjusted for small- sample bias. We apply the analytical bias formula from Pope (1990) using both Campbell et al.'s dataset, and an extended dataset...... with quarterly data from 1952 to 2006. The results show that correcting the VAR parameters for small-sample bias has both quantitatively and qualitatively important e¤ects on the strategic intertemporal part of optimal portfolio choice, especially for bonds: for intermediate values of risk...

  1. Refusion of zircaloy scraps by VAR (vacuum arc remelting): preliminary results; Fusao de cavacos de zircaloy por VAR: resultados preliminares

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L.A.T.; Mucsi, C.S.; Sato, I.M.; Rossi, J.L.; Martinez, L.G., E-mail: lgallego@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Correa, H.P.S. [Universidade Federal do Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil); Orlando, M.T.D. [Universidade Federal do Espirito Santo (UFES), Vitoria, ES (Brazil)

    2010-07-01

    Fuel elements and structural components of the core of PWR nuclear reactors are made in zirconium alloys known as Zircaloy. Machining chips and shavings resulting from the manufacturing of these components can not be discarded as scrap, once these alloys are strategic materials for the nuclear area, have high costs and are not produced in Brazil on an industrial bases and, consequently, are imported for the manufacture of nuclear fuel. The reuse of Zircaloy chips has economic, strategic and environmental aspects. In this work is proposed a process for recycling Zircaloy scraps using a VAR (vacuum arc remelting) furnace in order to obtain ingots suitable for the manufacture of components of the reactors. The ingots obtained are being studied in order to verify the influence of processing on composition and microstructure of the remelted material. In this work are presented preliminary results of the composition of obtained ingots compared to start material and the resulting microstructure. (author)

  2. Antigen Export Reduces Antigen Presentation and Limits T Cell Control of M. tuberculosis.

    Science.gov (United States)

    Srivastava, Smita; Grace, Patricia S; Ernst, Joel D

    2016-01-13

    Persistence of Mycobacterium tuberculosis results from bacterial strategies that manipulate host adaptive immune responses. Infected dendritic cells (DCs) transport M. tuberculosis to local lymph nodes but activate CD4 T cells poorly, suggesting bacterial manipulation of antigen presentation. However, M. tuberculosis antigens are also exported from infected DCs and taken up and presented by uninfected DCs, possibly overcoming this blockade of antigen presentation by infected cells. Here we show that the first stage of this antigen transfer, antigen export, benefits M. tuberculosis by diverting bacterial proteins from the antigen presentation pathway. Kinesin-2 is required for antigen export and depletion of this microtubule-based motor increases activation of antigen-specific CD4 T cells by infected cells and improves control of intracellular infection. Thus, although antigen transfer enables presentation by bystander cells, it does not compensate for reduced antigen presentation by infected cells and represents a bacterial strategy for CD4 T cell evasion.

  3. THE LYMPH SELF ANTIGEN REPERTOIRE

    Directory of Open Access Journals (Sweden)

    Laura eSantambrogio

    2013-12-01

    Full Text Available The lymphatic fluid originates from the interstitial fluid which bathes every parenchymal organ and reflects the omic composition of the tissue from which it originates in its physiological or pathological signature. Several recent proteomic analyses have mapped the proteome-degradome and peptidome of this immunologically relevant fluid pointing to the lymph as an important source of tissue-derived self-antigens. A vast array of lymph-circulating peptides have been mapped deriving from a variety of processing pathways including caspases, cathepsins, MMPs, ADAMs, kallikreins, calpains and granzymes, among others. These self peptides can be directly loaded on circulatory dendritic cells and expand the self-antigenic repertoire available for central and peripheral tolerance.

  4. Final Critical Habitat for the Kincaid's lupine (Lupinus sulphureus (=oreganus) ssp. kincaidii (=var. kincaidii))

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas where final critical habitat for the Kincaid's lupine (Lupinus sulphureus (=oreganus) ssp. kincaidii (=var. kincaidii))...

  5. Final Critical Habitat for the Willamette daisy (Erigeron decumbens var. decumbens)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas where final critical habitat for the Willamette daisy (Erigeron decumbens var. decumbens) occur.

  6. A Vector AutoRegressive (VAR) Approach to the Credit Channel for ...

    African Journals Online (AJOL)

    user1

    significance of monetary policy and the bank lending view of the credit channel for Mauritius, which is particularly relevant at these times. A vector autoregressive (VAR) ..... with ∆ the difference operator and B the lag operator. 2.2 Causality.

  7. modeling and analysis of a three-phase solid-state var compensator

    African Journals Online (AJOL)

    Several methods of var compensation have been applied in solv- ing these problems. ... quires costly and complex external circuits that reduce circuit reliability. One of ..... control is realized without computation of the re- quired reactive power.

  8. Final Critical Habitat for the Kincaid's lupine (Lupinus sulphureus (=oreganus) ssp. kincaidii (=var. kincaidii))

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas where final critical habitat for the Kincaid's lupine (Lupinus sulphureus (=oreganus) ssp. kincaidii (=var. kincaidii))...

  9. Bahiensol, a new glycerolipid from a cultured myxomycete Didymium bahiense var. bahiense.

    Science.gov (United States)

    Misono, Yuka; Ishibashi, Masami; Ito, Akira

    2003-05-01

    Bahiensol (1), a new glycerolipid with antimicrobial activity has been isolated from a cultured plasmodium of myxomycete Didymium bahiense var. bahiense and its planar structure was elucidated by spectral data.

  10. Three new C19-diterpenoid alkaloids from Delphinium laxicymosum var. Pilostachyum

    Institute of Scientific and Technical Information of China (English)

    Ping Tang; Dong Lin Chen; Qiao Hong Chen; Xi Xian Jian; Feng Peng Wang

    2007-01-01

    Three new lycoctonine-type C19-diterpenoid alkaloids, laxicymine 1, laxicymisine 2, and laxicyminine 3 have been isolated from the whole herb of Delphinium laxicymosum var.pilostachyum W.T.Wang.Their structures were established by spectra data.

  11. Rabdosia japonica var. glaucocalyx Flavonoids Fraction Attenuates Lipopolysaccharide-Induced Acute Lung Injury in Mice

    National Research Council Canada - National Science Library

    Chu, Chun-Jun; Xu, Nai-Yu; Li, Xian-Lun; Xia, Long; Zhang, Jian; Liang, Zhi-Tao; Zhao, Zhong-Zhen; Chen, Dao-Feng

    2014-01-01

    Rabdosia japonica var. glaucocalyx (Maxim.) Hara, belonging to the Labiatae family, is widely used as an anti-inflammatory and antitumor drug for the treatment of different inflammations and cancers. Aim of the Study...

  12. Final Critical Habitat for the Wenatchee Mountains Checkermallow (Sidalcea oregana var. calva)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Wenatchee Mountains checker-mallow (Sidalcea oregana var. calva) occur based on the...

  13. Sobre la validez taxonómica de Epithemia Zebra var. Elongata (Epithemiaceae, Bacillariophyceae

    Directory of Open Access Journals (Sweden)

    Gabriela Gorritti

    2000-01-01

    Full Text Available Gorritti, G., Sala, S. E. & Guerrero, J. M. 2000. Sobre la validez taxonómica de Epithemiazebra var. elongata (Epithemiaceae, Bacillariophyceae. Darwiniana 38(3-4: 285-289.Se revisaron materiales de Epithemia zebra var. elongata Grunow ex Frenguelli para establecer lavalidez de este taxón. Se estudiaron con microscopio óptico y electrónico de barrido, ejemplares de lacolección Frenguelli y otros recientemente coleccionados en Tierra del Fuego . El análisis de la variaciónpoblacional de los caracteres morfológicos y morfométricos, y la comparación con los taxones afines:Epithemia adnata (Kützing Brébisson y E. adnata var. minor (Peragallo & Héribaud Patrick, demostróque no existen diferencias entre ellos por lo que E. zebra var. elongata debe ser considerada sinónimo deE. adnata

  14. A New 6,7-Seco-Ent-Kaurane Diterpenoid from Isodon eriocalyx Var. laxiflora

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new 6,7-seco-ent-kaurane diterpenoid, together with two known ones, was isolated from the leaves of Isodon eriocalyx var. laxiflora C. Y. Wu & H. W. Li. Their structures were established by spectroscopic methods.

  15. Final Critical Habitat for the Huachuca water umbel (Lilaeopsis schaffneriana var. recurva)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Huachuca water umbel (Lilaeopsis schaffneriana var. recurva) occur based on the...

  16. Bacterial phospholipide antigens and their taxonomic significance.

    Science.gov (United States)

    Karalnik, B V; Razbash, M P; Akhmetova, E A

    1981-01-01

    The investigation of interrelationships between the phospholipides of various microorganisms (33 strains of corynebacteria, mycobacteria and staphylococci) using crossed antibody neutralization reactions with phospholipide antigenic erythrocyte diagnostic was used for the assessment of the degree of antigenic propinquity and antigenic differences between the phospholipides of bacteria of the same species, genus, and of different genera. The role of the determinants of the corresponding (their own) and "foreign" genera in the antigenic differences between the phospholipides of the microorganisms investigated was established. On the basis of the results obtained the conclusion has been drawn that the method of assessment of antigenic interrelationships between phospholipides can be used for the study of some taxonomic problems.

  17. [HLA antigens in juvenile rheumatoid arthritis].

    Science.gov (United States)

    Rumba, I V; Sochnev, A M; Kukaĭne, E M; Burshteĭn, A M; Benevolenskaia, L I

    1990-01-01

    Antigens of I class HLA system (locus A and B) were investigated in 67 patients of Latvian nationality suffering from juvenile rheumatoid arthritis (JRA). Associations of HLA antigens with juvenile rheumatoid arthritis partially coincided with the ones revealed earlier. Typing established an increased incidence of antigen B27 (p less than 0.01) and gaplotype A2, B40 (p less than 0.01). Antigen B15 possessed a protective action with respect to JRA. Interlocus combinations demonstrated a closer association with the disease than a single antigen. The authors also revealed markers of various clinico-anatomical variants of JRA.

  18. Stratospheric age of air computed with trajectories based on various 3D-Var and 4D-Var data sets

    Directory of Open Access Journals (Sweden)

    M. P. Scheele

    2005-01-01

    Full Text Available The age of stratospheric air is computed with a trajectory model, using ECMWF ERA-40 3D-Var and operational 4D-Var winds. Analysis as well as forecast data are used. In the latter case successive forecast segments are put together to get a time series of the wind fields. This is done for different forecast segment lengths. The sensitivity of the computed age to the forecast segment length and assimilation method are studied, and the results are compared with observations and with results from a chemistry transport model that uses the same data sets. A large number of backward trajectories are started in the stratosphere, and from the fraction of these trajectories that has passed the tropopause the age of air is computed. First, for ten different data sets 50-day backward trajectories starting in the tropical lower stratosphere are computed. The results show that in this region the computed cross-tropopause transport decreases with increasing forecast segment length. Next, for three selected data sets (3D-Var 24-h and 4D-Var 72-h forecast segments, and 4D-Var analyses 5-year backward trajectories are computed that start all over the globe at an altitude of 20km. For all data sets the computed ages of air in the extratropics are smaller than the observation-based age. For 4D-Var forecast series they are closest to the observation-based values, but still 0.5-1.5 year too small. Compared to the difference in age between the results for the different data sets, the difference in age between the trajectory and the chemistry transport model results is small.

  19. Evidence for the involvement of VAR2CSA in pregnancy-associated malaria

    DEFF Research Database (Denmark)

    Salanti, Ali; Dahlbäck, Madeleine; Turner, Louise;

    2004-01-01

    by endemic plasma in a sex-specific and parity-dependent manner; (c) that high anti-VAR2CSA IgG levels can be found in pregnant women from both West and East Africa; and (d) that women with high plasma levels of anti-VAR2CSA IgG give birth to markedly heavier babies and have a much lower risk of delivering...

  20. [Content and distribution of active components in cultivated and wild Taxus chinensis var. mairei plants].

    Science.gov (United States)

    Yu, Shao-Shuai; Sun, Qi-Wu; Zhang, Xiao-Ping; Tian, Sheng-Ni; Bo, Pei-Lei

    2012-10-01

    Taxus chinensis var. mairei is an endemic and endangered plant species in China. The resources of T. chinensis var. mairei have been excessively exploited due to its anti-cancer potential, accordingly, the extant T. chinensis var. mairei population is decreasing. In this paper, ultrasonic extraction and HPLC were adopted to determine the contents of active components paclitaxel, 7-xylosyltaxol and cephalomannine in cultivated and wild T. chinensis var. mairei plants, with the content distribution of these components in different parts of the plants having grown for different years and at different slope aspects investigated. There existed obvious differences in the contents of these active components between cultivated and wild T. chinensis var. mairei plants. The paclitaxel content in the wild plants was about 0.78 times more than that in the cultivated plants, whereas the 7-xylosyltaxol and cephalomannine contents were slishtly higher in the cultivated plants. The differences in the three active components contents between different parts and tree canopies of the plants were notable, being higher in barks and upper tree canopies. Four-year old plants had comparatively higher contents of paclitaxel, 7-xylosyltaxol and cephalomannine (0.08, 0.91 and 0.32 mg x g(-1), respectively), and the plants growing at sunny slope had higher contents of the three active components, with significant differences in the paclitaxel and 7-xylosyltaxol contents and unapparent difference in the cephalomannine content of the plants at shady slope. It was suggested that the accumulation of the three active components in T. chinensis var. mairei plants were closely related to the sunshine conditions. To appropriately increase the sunshine during the artificial cultivation of T. chinensis var. mairei would be beneficial to the accumulation of the three active components in T. chinensis var. mairei plants.

  1. Myte: Var Danmark det første land, der ophævede slaveriet?

    DEFF Research Database (Denmark)

    Jørgensen, Helle

    2014-01-01

    Danskere har tit travlt med at vaske hænder i forbindelse med slavehandlen, for vi var jo det første land, der lovgav mod slaveriet. Men er det nu også sandt?......Danskere har tit travlt med at vaske hænder i forbindelse med slavehandlen, for vi var jo det første land, der lovgav mod slaveriet. Men er det nu også sandt?...

  2. 3-Hydroxy Fatty Acids from the Flowers of Hypericum lysimachioides var. lysimachioides

    OpenAIRE

    ÖZEN, Hasan Çetin; BAŞHAN, Mehmet

    2004-01-01

    Fatty acid methyl esters in the leaves and flowers of Hypericum lysimachioides var. lysimachioides (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The flowers of H. lysimachioides var. lysimachioides produced unusual 3-hydroxy fatty acids [3-hydroxy- tetradecanoic acid (3-OH-C14:0) and 3-hydroxy-octadecanoic acid (3-OH-C18:0)], along with other normal fatty acids. Major components were linolenic and palmitic acids for both leaves and flowers.

  3. Isolation and structure elucidation of a new prenylcoumarin from Murraya paniculata var. omphalocarpa (Rutaceae).

    Science.gov (United States)

    Kinoshita, Takeshi; Shimada, Motoko

    2002-01-01

    A new C-8 prenylated 5,7-dimethoxycoumarin named omphamurrayin was isolated from the leaves of Murraya paniculata var. omphalocarpa, and its structure was established as 5,7-dimethoxy-8-(1-oxo-2-senecioyl-3-methyl-3-butenyl)-2H-1-benzopyran-2-one on the basis of the spectroscopic evidence. The taxonomic status of M. paniculata var. omphalocarpa is briefly discussed, along with its synonymity to M. paniculata from the chemosystematic viewpoint.

  4. Common antigens between hydatid cyst and cancers

    Directory of Open Access Journals (Sweden)

    Shima Daneshpour

    2016-01-01

    Full Text Available Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended.

  5. Stable solid-phase Rh antigen.

    Science.gov (United States)

    Yared, M A; Moise, K J; Rodkey, L S

    1997-12-01

    Numerous investigators have attempted to isolate the Rh antigens in a stable, immunologically reactive form since the discovery of the Rh system over 56 years ago. We report here a successful and reproducible approach to solubilizing and adsorbing the human Rh antigen(s) to a solid-phase matrix in an antigenically active form. Similar results were obtained with rabbit A/D/F red blood cell antigens. The antigen preparation was made by dissolution of the red blood cell membrane lipid followed by fragmentation of the residual cytoskeleton in an EDTA solution at low ionic strength. The antigenic activity of the soluble preparations was labile in standard buffers but was stable in zwitterionic buffers for extended periods of time. Further studies showed that the antigenic activity of these preparations was enhanced, as was their affinity for plastic surfaces, in the presence of acidic zwitterionic buffers. Adherence to plastic surfaces at low pH maintained antigenic reactivity and specificity for antibody was retained. The data show that this approach yields a stable form of antigenically active human Rh D antigen that could be used in a red blood cell-free assay for quantitative analysis of Rh D antibody and for Rh D antibody immunoadsorption and purification.

  6. Common antigens between hydatid cyst and cancers

    Science.gov (United States)

    Daneshpour, Shima; Bahadoran, Mehran; Hejazi, Seyed Hossein; Eskandarian, Abas Ali; Mahmoudzadeh, Mehdi; Darani, Hossein Yousofi

    2016-01-01

    Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended. PMID:26962511

  7. Experiencing variation

    DEFF Research Database (Denmark)

    Kobayashi, Sofie; Berge, Maria; Grout, Brian William Wilson

    2017-01-01

    This study contributes towards a better understanding of learning dynamics in doctoral supervision by analysing how learning opportunities are created in the interaction between supervisors and PhD students, using the notion of experiencing variation as a key to learning. Empirically, we have based...... were discussed, created more complex patterns of variation. Both PhD students and supervisors can learn from this. Understanding of this mechanism that creates learning opportunities can help supervisors develop their competences in supervisory pedagogy....

  8. Constraints on the Genetic and Antigenic Variability of Measles Virus.

    Science.gov (United States)

    Beaty, Shannon M; Lee, Benhur

    2016-04-21

    Antigenic drift and genetic variation are significantly constrained in measles virus (MeV). Genetic stability of MeV is exceptionally high, both in the lab and in the field, and few regions of the genome allow for rapid genetic change. The regions of the genome that are more tolerant of mutations (i.e., the untranslated regions and certain domains within the N, C, V, P, and M proteins) indicate genetic plasticity or structural flexibility in the encoded proteins. Our analysis reveals that strong constraints in the envelope proteins (F and H) allow for a single serotype despite known antigenic differences among its 24 genotypes. This review describes some of the many variables that limit the evolutionary rate of MeV. The high genomic stability of MeV appears to be a shared property of the Paramyxovirinae, suggesting a common mechanism that biologically restricts the rate of mutation.

  9. BIOCHEMICAL STUDIES ON SO-CALLED SYPHILIS ANTIGEN.

    Science.gov (United States)

    Noguchi, H; Bronfenbrenner, J

    1911-01-01

    of tissue is very variable. (c) Substances Soluble in Ether, Alcohol, and Aceton.-In this group are found varying amounts of fatty acids, both saturated and unsaturated, some neutral fats, cholesterin and many unidentified lipoidal bodies. This group causes either hemolysis or inhibition, of hemolysis. In other words, it is anticomplementary as well as hemolytic in the majority of preparations. At the same time, in some preparations it is, to a certain extent, antigenic. This great variation in the amounts of these substances in given extracts renders their presence in the antigen preparation undesirable. It is not denied, however, that, when added in adequate quantities, some of these substances may improve the activity of the antigenic lipoids. (d) Substances Insoluble in Aceton.-This group of substances consists of phosphatids. The best known among them is, of course, lecithin. Besides lecithin, however, there must be various other phosphatids present in this fraction. It will be noticed that the precipitate formed by mixing the ethereal solution with aceton contains a certain amount of lipoids insoluble in ether as well as in alcohol. Before the fractionation in aceton, all lipoids were soluble in ether or ethyl alcohol. Further analytical work on the nature of the phosphatids contained in this fraction is necessary. This fraction, in general, is more constant in amount in the various liver extracts. Biologically considered, it is the most important. It is usually non-hemolytic, frequently anticomplementary, but much more strongly antigenic than the other fractions. The antigenic strength varies with different preparations, being almost absent in the extracts derived from fatty livers. An aceton insoluble fraction may be strongly antigenic without any other auxiliary effects, or may be accompanied by an anticomplementary property. This fraction does not cause the so-called non-specific reaction with an active human serum. For these reasons it is recommended (as

  10. Valor nutricional e potencial nutracêutico de inflorescências de couve-nabo (Brassica napus var napus) e couve-tronchuda (Brassica oleraceae var costata).

    OpenAIRE

    Barros, Lillian; Batista, Cátia Emanuela Oliveira; Carvalho, Ana Maria; FERREIRA, ISABEL C.F.R.

    2012-01-01

    Na Península Ibérica as verduras (silvestres ou tradicionalmente cultivadas) têm sido alimentos importantes na dieta humana. O valor nutricional de verduras e os seus benefícios para a saúde têm sido reconhecidos como importantes alvos de investigação. Os grelos, inflorescências da couve-nabo (Brassica napus L. var. napus) e os espigos, inflorescências da couve-tronchuda (Brassica oleracea L. var. costata DC.) são exemplos de espécies tradicionalmente cultivadas e amplamente consumidas nas re...

  11. Valor nutricional e potencial nutracêutico de inflorescências de couve-nabo (Brassica napus var napus) e couve-tronchuda (Brassica oleraceae var costata).

    OpenAIRE

    Barros, Lillian; Batista, Cátia Emanuela Oliveira; Carvalho, Ana Maria; Isabel C. F. R. Ferreira

    2012-01-01

    Na Península Ibérica as verduras (silvestres ou tradicionalmente cultivadas) têm sido alimentos importantes na dieta humana. O valor nutricional de verduras e os seus benefícios para a saúde têm sido reconhecidos como importantes alvos de investigação. Os grelos, inflorescências da couve-nabo (Brassica napus L. var. napus) e os espigos, inflorescências da couve-tronchuda (Brassica oleracea L. var. costata DC.) são exemplos de espécies tradicionalmente cultivadas e amplamente consumidas nas re...

  12. Penetration, Post-penetration Development, and Reproduction of Meloidogyne incognita on Cucumis melo var. texanus.

    Science.gov (United States)

    Faske, T R

    2013-03-01

    Cucumis melo var. texanus, a wild melon commonly found in the southern United States and two accessions, Burleson Co. and MX 1230, expressed resistance to Meloidogyne incognita in preliminary experiments. To characterize the mechanism of resistance, we evaluated root penetration, post-penetration development, reproduction, and emigration of M. incognita on these two accessions of C. melo var. texanus. Additionally, we evaluated 22 accessions of C. melo var. texanus for their reaction against M. incognita in a greenhouse experiment. Fewer (P ≤ 0.05) J2 penetrated the root system of C. melo var. texanus accessions (Burleson Co. and MX 1230) and C. metuliferus (PI 482452) (resistant control), 7 days after inoculation (DAI) than in C. melo 'Hales Best Jumbo' (susceptible control). A delayed (P ≤ 0.05) rate of nematode development was observed at 7, 14, and 21 DAI that contributed to lower (P ≤ 0.05) egg production on both accessions and C. metuliferus compared with C. melo. Though J2 emigration was observed on all Cucumis genotypes a higher (P ≤ 0.05) rate of J2 emigration was observed from 3 to 6 DAI on accession Burleson Co. and C. metuliferus than on C. melo. The 22 accessions of C. melo var. texanus varied relative to their reaction to M. incognita with eight supporting similar levels of nematode reproduction to that of C. metuliferus. Cucumis melo var. texanus may be a useful source of resistance against root-knot nematode in melon.

  13. Semi-nonparametric VaR forecasts for hedge funds during the recent crisis

    Science.gov (United States)

    Del Brio, Esther B.; Mora-Valencia, Andrés; Perote, Javier

    2014-05-01

    The need to provide accurate value-at-risk (VaR) forecasting measures has triggered an important literature in econophysics. Although these accurate VaR models and methodologies are particularly demanded for hedge fund managers, there exist few articles specifically devoted to implement new techniques in hedge fund returns VaR forecasting. This article advances in these issues by comparing the performance of risk measures based on parametric distributions (the normal, Student’s t and skewed-t), semi-nonparametric (SNP) methodologies based on Gram-Charlier (GC) series and the extreme value theory (EVT) approach. Our results show that normal-, Student’s t- and Skewed t- based methodologies fail to forecast hedge fund VaR, whilst SNP and EVT approaches accurately success on it. We extend these results to the multivariate framework by providing an explicit formula for the GC copula and its density that encompasses the Gaussian copula and accounts for non-linear dependences. We show that the VaR obtained by the meta GC accurately captures portfolio risk and outperforms regulatory VaR estimates obtained through the meta Gaussian and Student’s t distributions.

  14. Working alliance inventory applied to virtual and augmented reality (WAI-VAR): psychometrics and therapeutic outcomes.

    Science.gov (United States)

    Miragall, Marta; Baños, Rosa M; Cebolla, Ausiàs; Botella, Cristina

    2015-01-01

    This study examines the psychometric properties of the Working Alliance Inventory-Short (WAI-S) adaptation to Virtual Reality (VR) and Augmented Reality (AR) therapies (WAI-VAR). The relationship between the therapeutic alliance (TA) with VR and AR and clinically significant change (CSC) is also explored. Seventy-five patients took part in this study (74.7% women, M age = 34.41). Fear of flying and adjustment disorder patients received VR therapy, and cockroach phobia patients received AR therapy. Psychometric properties, CSC, one-way ANOVA, Spearman's Correlations and Multiple Regression were calculated. The WAI-VAR showed a unidimensional structure, high internal consistency and adequate convergent validity. "Not changed" patients scored lower on the WAI-VAR than "improved" and "recovered" patients. Correlation between the WAI-VAR and CSC was moderate. The best fitting model for predicting CSC was a linear combination of the TA with therapist (WAI-S) and the TA with VR and AR (WAI-VAR), due to the latter variable slightly increased the percentage of variability accounted for in CSC. The WAI-VAR is the first validated instrument to measure the TA with VR and AR in research and clinical practice. This study reveals the importance of the quality of the TA with technologies in achieving positive outcomes in the therapy.

  15. [Supercritical CO2 fluid extraction and component analysis of leaves oil from Taxus chinensis var. mairei].

    Science.gov (United States)

    Tang, Bin; Zhang, Feng-su; Li, Xiang; Chen, Jian-wei; Yao, Xiao

    2013-12-01

    To research the optimal extraction process of supercritical CO2 extraction and analyze the component of the oil extracted from leaves of Taxus chinensis var. mairei. Using the yield of leaves oil from Taxus chinensis var. mairei as the index, investigated the effect of the extraction pressure, extraction temperature and extraction time on the extracting-rate of leaves oil. The chemical composition of the extracted leaves oil was analyzed by derivatized GC-MS. The optimal parameters of the supercritical CO2 extraction of the oil extracted from leaves of Taxus chinensis var. mairei were determined: CO2 compressor pump frequency was 10 Hz, the extraction pressure was 25 MPa and the temperature of extraction was 45 degrees C, the extraction time was 120 min, the isolator I pressure was 8.0 MPa and the temperature of extraction was 40 degrees C, the isolator II pressure was 5.0 MPa and the temperature of extraction was 35 degrees C. The extracted leaves oil was derivatized with boron trifluoride-methanol complex. Thirty-three kinds of fatty acids were identified by GC-MS. The yield of leaves oils are different from Taxus chinensis var. mairei from 3 habitats. The yield of leaves oil from Donggang, Wuxi city is the highest, about 2.61%. The kinds of fatty acids with high amounts in leaves oil from Taxus chinensis var. mairei is identical in general, the kinds of fatty acids with low amounts in leaves oil from Taxus chinensis var. mairei have differences.

  16. Working alliance inventory applied to virtual and augmented reality (WAI-VAR): psychometrics and therapeutic outcomes

    Science.gov (United States)

    Miragall, Marta; Baños, Rosa M.; Cebolla, Ausiàs; Botella, Cristina

    2015-01-01

    This study examines the psychometric properties of the Working Alliance Inventory-Short (WAI-S) adaptation to Virtual Reality (VR) and Augmented Reality (AR) therapies (WAI-VAR). The relationship between the therapeutic alliance (TA) with VR and AR and clinically significant change (CSC) is also explored. Seventy-five patients took part in this study (74.7% women, Mage = 34.41). Fear of flying and adjustment disorder patients received VR therapy, and cockroach phobia patients received AR therapy. Psychometric properties, CSC, one-way ANOVA, Spearman’s Correlations and Multiple Regression were calculated. The WAI-VAR showed a unidimensional structure, high internal consistency and adequate convergent validity. “Not changed” patients scored lower on the WAI-VAR than “improved” and “recovered” patients. Correlation between the WAI-VAR and CSC was moderate. The best fitting model for predicting CSC was a linear combination of the TA with therapist (WAI-S) and the TA with VR and AR (WAI-VAR), due to the latter variable slightly increased the percentage of variability accounted for in CSC. The WAI-VAR is the first validated instrument to measure the TA with VR and AR in research and clinical practice. This study reveals the importance of the quality of the TA with technologies in achieving positive outcomes in the therapy. PMID:26500589

  17. Hibridação interespecífica entre Gossmum hirsutum L. var. latifolium e G. Herbaceum L. var. africanum Interespecific hybridization between Gossypium hirsutum var. latifolium and G. Herbaceum var. africanum

    Directory of Open Access Journals (Sweden)

    Ederaldo José Chiavegato

    1985-01-01

    Full Text Available Foi obtida, pelos autores, variabilidade genética para resistência da fibra do algodoeiro a partir da hibridação entre a espécie alotetraplóide cultivada Gossypium hirsutum L. var. latifolium Hutch. e a espécie diplóide selvagem G. herbaceum L. vai. africanum Hutch. A metodologia empregada e as características agronômicas e tecnológicas da fibra do híbrido são descritas e discutidas. Visando à duplicação do número de cromossomos da espécie diplóide, foram realizados nove tratamentos com o alcalóide colchicina, em solução aquosa e em adição com pasta de lanolina, com diferentes concentrações e tempo de ação para o tratamento de sementes, radicelas e gemas apicais: revelou-se mais eficiente o de gemas apicais com colchicina a 1%, em pasta de lanolina, durante 32 horas. Diversos cruzamentos das plantas duplicadas com variedades comerciais de algodoeiro levaram à obtenção de híbrido estéril. A seguir, dois retrocruzamentos foram realizados, sendo que, a partir do primeiro, a fertilidade foi restaurada. Estas plantas, com características agronômicas promissoras, possuem grande variabilidade para resistência da fibra, num nível superior ao de G. hirsutum.Genetic variability was obtained by the authors for fiber strenght in cotton, through hybridization between the cultivated alotetraploid species Gossypium hirsutum L. var. latifolium Hutch. and the wild diploid species G. herbaceum L. africanum Hutch. The underlying methods and the hybrid's characteristics are reported and described. As a first step, the number of chromosomes in the diploid species was duplicated. Nine treatments with aqueous colchicina or colchicina in lanolina paste were carried out, comprising several concentrations and times of application to seeds, radicles and apical buds of the main stem. Success was obtained by treating apical buds with lanolina paste containing 1% colchicina, during 32 hours. Two hundred fourty five crosses between the

  18. Micropropagation of an endangered species Pinus armandii var. Amamiana

    Directory of Open Access Journals (Sweden)

    Katsuaki Ishii

    2013-12-01

    Full Text Available For micropropagation via organ culture, mature embryos were excised from the seeds of Pinus armandii. Franch. var. amamiana (Koidz. Hatusima, an endangered species only inhabiting the south west islands of Japan. Adventitious buds were induced on the surface of the embryo on 1/2 DCR medium containing BAP, and they grew shoots after subculturing to medium containing activated charcoal or a low concentration of thidiazuron. From the elongated shoots, root primordia and roots were induced in medium containing IBA as an auxine. We found that a low concentration of zeatin or BAP added to the medium was beneficial for plant regeneration of mature embryos of this species. For micropropagation via somatic embryogenesis, embryogenic cell suspensions were induced from a mature and immature seed of P. armandii var. amamiana on MS liquid medium supplemented with 1 ľM 2, 4-D and 3 ľM BAP. The suspensions were incubated in the dark at 250. Induced suspension cells were transferred to ammonium free MS liquid medium supplemented with 1 ľM 2, 4-D, 3 ľM BAP and 30m M L-glutamine and subcultured every 2 weeks. In the other set of the experiment, the induction rate of somatic embryogenesis was high with ammonium free half strength MS medium. In order to develop somatic embryos, the suspension cells were transferred to ammonium free MS medium supplemented with 10 ľM ABA, 0.2% activated charcoal, 10% PEG (MW6000, 30m M L-glutamine and 6% maltose. The cultures were incubated under a 16h light/8h dark photoperiod. After 1-2 months of culture, differentiation of embryos progressed and cotyledonary embryos were obtained. These embryos were transferred on ammonium free MS solid medium under 16 h photoperiod. After 2-3 weeks plantlets with roots and green cotyledons were obtained. Plantlets were transplanted to vermiculite containing modified MS liquid medium in 200 ml culture flasks, then out planted after habituation procedure.

  19. Changing selective pressure during antigenic changes in human influenza H3.

    Directory of Open Access Journals (Sweden)

    Benjamin P Blackburne

    2008-05-01

    Full Text Available The rapid evolution of influenza viruses presents difficulties in maintaining the optimal efficiency of vaccines. Amino acid substitutions result in antigenic drift, a process whereby antisera raised in response to one virus have reduced effectiveness against future viruses. Interestingly, while amino acid substitutions occur at a relatively constant rate, the antigenic properties of H3 move in a discontinuous, step-wise manner. It is not clear why this punctuated evolution occurs, whether this represents simply the fact that some substitutions affect these properties more than others, or if this is indicative of a changing relationship between the virus and the host. In addition, the role of changing glycosylation of the haemagglutinin in these shifts in antigenic properties is unknown. We analysed the antigenic drift of HA1 from human influenza H3 using a model of sequence change that allows for variation in selective pressure at different locations in the sequence, as well as at different parts of the phylogenetic tree. We detect significant changes in selective pressure that occur preferentially during major changes in antigenic properties. Despite the large increase in glycosylation during the past 40 years, changes in glycosylation did not correlate either with changes in antigenic properties or with significantly more rapid changes in selective pressure. The locations that undergo changes in selective pressure are largely in places undergoing adaptive evolution, in antigenic locations, and in locations or near locations undergoing substitutions that characterise the change in antigenicity of the virus. Our results suggest that the relationship of the virus to the host changes with time, with the shifts in antigenic properties representing changes in this relationship. This suggests that the virus and host immune system are evolving different methods to counter each other. While we are able to characterise the rapid increase in

  20. [Studies on the immunodiagnosis of rabbit clonorchiasis II. Immunoaffinity purification of whole worm antigen and characterization of egg, metacercaria and adult antigens of Clonorchis sinensis

    Science.gov (United States)

    Lee, Ok Ran; Chung, Pyung Rim; Nam, Hae Seon

    1988-06-01

    The sensitivity and specificity of crude and affinity-purified antigens of Clonorchis sinensis obtained from the infected rabbits were studied. Stage-specific antigenic proteins from the eggs, metacercariae and adult worms were characterized by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA) The results were as follows: The antibody-binding antigen (ABA) purified from whole worm crude antigen (WWA) by CNBr-activated Sepharose 4B affinity chromatography made 4 specific bands against rabbit anti-sera on Ouchterlony gel diffusion plate, while WWA made 7 bands. Major WWA protein bands by SDS-PAGE were found at 16,300-18,500 and 28,000-29,000 daltons, while major ABA protein bands were at 18,000-21,000 and 29,000-31,000 daltons. The reactivity of ABA with rabbit anti-sera in ELISA was remarkably less sensitive than that of WWA. Molecular weights of egg antigen (EGA), metacercarial antigen (MEA) and adult worm antigen (WWA) of C. sinensis ranged from 15,000-200,000 daltons, 15,000-100,000 daltons and 11,000-80,000 daltons, respectively. Major WWA proteins consisted mainly of polypeptide bands of low molecular weight, less than 31,000 daltons, while those of EGA and MEA consisted of higher molecular weights than 30,000 daltons. The ELISA reactivities of WWA to rabbit anti-sera were remarkably greater than those of MEA. EGA showed negative reaction throughout the experiments. WWA showed higher optical density (O.D.) than 1.0, when reacted with rabbit anti-sera obtained at 4-6 weeks after the infection. In the rabbit anti-sera later than 12 weeks after the infection, the O.D. reacting with WWA showed a plateau without variation. MEA showed relatively low O.D. values (0.6) in heavily infected groups. MEA reacted with rabbit anti-sera showed negative results on Ouchterlony gel diffusion plates. Summarizing the above results, it is suggested that the whole worm antigen prepared from the adult worms of C. sinensis is most highly

  1. De Novo Transcriptome Analysis of Cucumis melo L. var. makuwa.

    Science.gov (United States)

    Kim, Hyun A; Shin, Ah-Young; Lee, Min-Seon; Lee, Hee-Jeong; Lee, Heung-Ryul; Ahn, Jongmoon; Nahm, Seokhyeon; Jo, Sung-Hwan; Park, Jeong Mee; Kwon, Suk-Yoon

    2016-02-01

    Oriental melon (Cucumis melo L. var. makuwa) is one of six subspecies of melon and is cultivated widely in East Asia, including China, Japan, and Korea. Although oriental melon is economically valuable in Asia and is genetically distinct from other subspecies, few reports of genome-scale research on oriental melon have been published. We generated 30.5 and 36.8 Gb of raw RNA sequence data from the female and male flowers, leaves, roots, and fruit of two oriental melon varieties, Korean landrace (KM) and Breeding line of NongWoo Bio Co. (NW), respectively. From the raw reads, 64,998 transcripts from KM and 100,234 transcripts from NW were de novo assembled. The assembled transcripts were used to identify molecular markers (e.g., single-nucleotide polymorphisms and simple sequence repeats), detect tissue-specific expressed genes, and construct a genetic linkage map. In total, 234 single-nucleotide polymorphisms and 25 simple sequence repeats were screened from 7,871 and 8,052 candidates, respectively, between the KM and NW varieties and used for construction of a genetic map with 94 F2 population specimens. The genetic linkage map consisted of 12 linkage groups, and 248 markers were assigned. These transcriptome and molecular marker data provide information useful for molecular breeding of oriental melon and further comparative studies of the Cucurbitaceae family.

  2. Gene effect and heterosis in Capsicum baccatum var. pendulum

    Directory of Open Access Journals (Sweden)

    Artur Mendes Medeiros

    2014-06-01

    Full Text Available Heterosis has been exploited in Capsicum annuum commercial hybrids; however, the use of heterosis in C. baccatum still remains to be explored, and studies related to the genetics and breeding of this species are scarce. The present study aimed to estimate the combining ability of five parents of C. baccatum var. pendulum , representatives of two distinct types of fruits (namely, lady's finger and cambuci, to calculate heterosis and to evaluate the agronomic potential of the hybrids for yield and fruit quality. The hybrids were produced from a complete diallel without reciprocals. The parents and hybrids were evaluated under field conditions in a randomized block design with three replications, and the following traits were assessed: number of fruits per plant, fruit weight, yield per plant, fruit length, fruit diameter and soluble solids. All traits were significant for general and specific combining ability, indicating that additive and non-additive effects are involved in the genetic control of these traits. The hybrid combinations between the types lady's finger and cambuci provided elongated fruits with smaller diameters and greater weight compared with the parents of the cambuci type. However, these factors did not lead to a significant increase in the yield per plant due to the decreased number of fruits except in hybrid UENF 1616 x UENF 1732. Considering only the parents and hybrids within each type of fruit, the genitor UENF 1624 (lady's finger and the hybrid UENF 1639 x UENF 1732 (cambuci x cambuci stood out for achieving a high yield per plant.

  3. COPULA BASED VaR APPROACH FOR EUROPEAN STOCKS PORTFOLIO

    Directory of Open Access Journals (Sweden)

    Mária Bohdalová

    2013-06-01

    Full Text Available The paper gives stochastic assessments of the financial crisis and discusses the Value at Risk European stocks from the point of view of copula based approach. Copula techniques can be based on the connection between rank correlation and certain one–parameter bivariate copulas. This relation allows easy calibration of the parameters. We use more general numerical calibration techniques that are based on maximum likelihood estimation (MLE. Using this approach we want to estimate VaR of the EU stocks portfolio using Monte Carlo simulation. The focus will be on modelling the interdependence between two risk factor returns. We suppose that the risk factor returns have some assumed marginal distributions, which need not be identical, and their dependency is modelled with copulas. We find that standard parametric copula functions (such as Gaussian are not able to provide a good fit to the data. This is especially true when one or more of the marginal distributions has fat tails. We overcome this problem by fitting a t–copula with different marginal which can approximate any possible shape for the joint density.

  4. [Triterpenoid saponins from flower bud of Jasminum officinale var. grandiflorum].

    Science.gov (United States)

    Zhao, Gui-Qin; Dong, Jun-Xing

    2008-01-01

    To study the chemical constituent bud of the flowers of Jasminum officinale var. grandiflorum. The compounds were isolated and purified by recrystallization and chromatography on silica gel and Sephadex LH - 20 column. Their structures were elucidated on the basis of physicochemical properties and spectral analysis. Six triterpenoid saponins were identified as 3-O-alpha-L-rhamnopyranosyl (1 --> 2)-beta-D-xylopyranosyl- hederagenin-28-O-beta-D-galactopyranosyl (1 --> 6)-beta-D-galactopyranosyl ester (1), hederagenin-3-O-beta-D-glucopyranosyl (1 --> 3)-alpha-L-arabinopyranoside (2), 2alpha, 3beta, 23-trihydroxyolean-12-en-28-oic-O-beta-D-glucopyranosyl ester (3), hederagenin-3-O-beta-D-xylopyranosyl (1 --> 3)-alpha-L-rhamnopyranosyl (1 --> 2)-alpha-L-arabinopyranoside (4), 2alpha, 3beta, 23-trihydroxyolean-12-en-28-oic-O-alpha-L-rhamnopyranosyl (1 --> 4)-beta-D-glucopyranosyl (1 --> 6)-beta-D-glucopyranosyl ester (5), hederagenin-3-O-alpha-L-rhamnopyranosyl (1 --> 2)-alpha-L-arabinopyranoside (6). Compound 1 is a new compound. Compounds 2, 3, 4, 5, 6 were isolated from the genus Jasminum for the first time.

  5. Bioactive phenylpropanoid analogues from Piper betle L. var. haldia leaves.

    Science.gov (United States)

    Atiya, Akhtar; Sinha, Barij Nayan; Lal, Uma Ranjan

    2017-02-15

    Phytochemical analyses of the chloroform extract of Piper betle L. var. birkoli, Piperaceae, leaves led to the isolation of two new phenylpropanoid analogues: bis-chavicol dodecanoyl ester (2) and bis-hydroxychavicol dodecanoyl ester (3), along with one known compound: allyl-3-methoxy-4-hydroxybenzene (1) on the basis of spectroscopic data 1D ((1)H and (13)C) and 2D ((1)H-(1)H COSY and HMBC) NMR, as well as ESI-MS, FT-IR, HR-ESI-MS and LC-ESI-MS. Compound 2 and 3 exhibited excellent antioxidant DPPH radical scavenging activity with IC50 values of 12.67 μg/mL and 1.08 μg/mL compared to ascorbic acid as a standard antioxidant drug with IC50 value of 6.60 μg/mL. Evaluation of cytotoxic activity against two human oral cancer cell lines (AW13516 and AW8507) showed significant effect with GI50 values of 19.61 and 23.01 μg/mL for compound 2 and 10.25 and 13.12 μg/mL for compound 3, compared to Doxorubicin(®) as a standard cytotoxic drug with GI50 value of < 10 μg/mL.

  6. Micropropagation of globe artichoke (Cynara cardunculus L. var. scolymus).

    Science.gov (United States)

    Iapichino, Giovanni

    2013-01-01

    The globe artichoke (Cynara cardunculus L. var. scolymus) is a perennial plant cultivated in the Mediterranean region and the Americas for its edible young flower heads. Although vegetative propagation by offshoots or by "ovoli" (underground dormant axillary buds) has been the primary method of propagation, the potential for the diffusion of diseases and the phenotypic variability can be very high. The propagation of this species by axillary shoot proliferation from in vitro-cultured meristems produces systemic pathogen-free plants and a higher multiplication rate as compared to that obtained by conventional agamic multiplication. Axillary shoot proliferation can be induced from excised shoot apices cultured on Murashige and Skoog agar solidified medium supplemented with various concentrations of cytokinins and auxins, depending on genotype. For the production of virus-free plants, meristems, 0.3-0.8 mm long are excised from shoot apices and surface sterilized. The transfer of artichoke microshoots to a medium lacking cytokinins or with low cytokinin concentration is critical for rooting. Adventitious roots develop within 3-5 weeks after transfer to root induction MS medium containing NAA or IAA at various concentrations. However, in vitro rooting frequency rate is dependent on the genotype and the protocol used. Acclimatization of in vitro microshoots having 3-4 roots is successfully accomplished; plantlets develop new roots in ex vitro conditions and continue to grow.

  7. Toxicological assessment of nattokinase derived from Bacillus subtilis var. natto.

    Science.gov (United States)

    Lampe, Bradley J; English, J Caroline

    2016-02-01

    Subtilisin NAT, commonly known as "nattokinase," is a fibrinolytic enzyme produced by the bacterial strain B. subtilis var. natto, which plays a central role in the fermentation of soybeans into the popular Japanese food natto. Recent studies have reported on the potential anticoagulatory and antihypertensive effects of nattokinase administration in humans, with no indication of adverse effects. To evaluate the safety of nattokinase in a more comprehensive manner, several GLP-compliant studies in rodents and human volunteers have been conducted with the enzyme product, NSK-SD (Japan Bio Science Laboratory Co., Ltd., Japan). Nattokinase was non-mutagenic and non-clastogenic in vitro, and no adverse effects were observed in 28-day and 90-day subchronic toxicity studies conducted in Sprague-Dawley rats at doses up to 167 mg/kg-day and 1000 mg/kg-day, respectively. Mice inoculated with 7.55 × 10(8) CFU of the enzyme-producing bacterial strain showed no signs of toxicity or residual tissue concentrations of viable bacteria. Additionally consumption of 10 mg/kg-day nattokinase for 4 weeks was well tolerated in healthy human volunteers. These findings suggest that the oral consumption of nattokinase is of low toxicological concern. The 90-day oral subchronic NOAEL for nattokinase in male and female Sprague-Dawley rats is 1000 mg/kg-day, the highest dose tested. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Bauhinia variegata var. variegata lectin: isolation, characterization, and comparison.

    Science.gov (United States)

    Chan, Yau Sang; Ng, Tzi Bun

    2015-01-01

    Bauhinia variegata var. variegata seeds are rich in proteins. Previously, one of the major storage proteins of the seeds was found to be a trypsin inhibitor that possessed various biological activities. By using another purification protocol, a glucoside- and galactoside-binding lectin that demonstrated some differences from the previously reported B. variegata lectin could be isolated from the seeds. It involved affinity chromatography on Affi-gel blue gel, ion exchange chromatography on Q-Sepharose and Mono Q, and also size exclusion chromatography on Superdex 75. The lectin was not retained on Affi-gel blue gel but interacted with Q-Sepharose. The lectin was a 64-kDa protein with two 32-kDa subunits. It had low thermostability (stable up to 50 °C) and moderate pH stability (stable in pH 3-10). It exhibited anti-proliferative activity on nasopharyngeal carcinoma HONE1 cells with an IC50 of 12.8 μM after treatment for 48 h. It also slightly inhibited the growth of hepatoma HepG2 cells. The lectin may have potential in aiding cancer treatments.

  9. Transport of Bacillus thuringiensis var. kurstaki via fomites.

    Science.gov (United States)

    Van Cuyk, Sheila; Veal, Lee Ann B; Simpson, Beverley; Omberg, Kristin M

    2011-09-01

    The intentional and controlled release of an aerosolized bacterium provides an opportunity to investigate the implications of a biological attack. Since 2006, Los Alamos National Laboratory has worked with several urban areas, including Fairfax County, VA, to design experiments to evaluate biodefense concepts of operations using routine spraying of Bacillus thuringiensis var. kurstaki (Btk). Btk is dispersed in large quantities as a slurry to control the gypsy moth, Lymantria dispar. Understanding whether personnel and equipment pick up residual contamination during sampling activities and transport it to other areas is critical for the formulation of appropriate response and recovery plans. While there is a growing body of literature surrounding the transmission of viral diseases via fomites, there is limited information on the transport of Bacillus species via this route. In 2008, LANL investigated whether field sampling activities conducted near sprayed areas, post-spray, resulted in measurable cross-contamination of sampling personnel, equipment, vehicles, and hotel rooms. Viable Btk was detected in all sample types, indicating transport of the agent occurred via fomites.

  10. ANTIPROLIFERATIVE PROTEIN FROM TRICHOSANTHES CUCUMERINA L. VAR ANGUINA (L. HAINES

    Directory of Open Access Journals (Sweden)

    CHURIYAH

    2010-01-01

    Full Text Available Three proteins were isolated from plant parts of Trichosanthes cucumerina L. var anguina (L. Haines, they were TF2 from fruit, TS3 from seed and TR3 from root with molecular masses (Mr approximately 16 - 64 kDa on SDS-PAGE characterization. The proteins were extracted with Phosphate Buffer Saline (PBS, then they were precipitated using 80% saturated ammonium sulphate continued with the dialysis using cellophane. The dialysate was fractionated through gel filtration chromatography. The highest yield of protein was 1.109% from the seed (TS3, then 0.356% from the root (TR3, while the lowest was 0.014% from the fruit (TF2. The Lethal Concentration 50 (LC of proteins on brine shrimp lethality test was 50within range of 19 µg/ml - 25 µg/ml. The cytotoxicity test of the TR3 and TS3 proteins on cancer cell lines indicated that both of the proteins could inhibit proliferation of HeLa and K-562 cells with IC up to 45 µg/ml. It is recommended to conduct further researches on 50Trichosanthes plant as a herbal medicine to treat cancer.

  11. Phenolic Glucosides from Dendrobium aurantiacum var. denneanum and Their Bioactivities

    Directory of Open Access Journals (Sweden)

    Liang Xiong

    2013-05-01

    Full Text Available A new 8,4¢-oxyneolignane glucoside 1 has been isolated from the stems of Dendrobium aurantiacum var. denneanum together with six known phenolic glucosides 2-7. The structure of the new compound, including its absolute configuration, was determined by spectroscopic and chemical methods as (–-(7S,8R,7¢E-4-hydroxy-3,3¢,5,5¢-tetramethoxy-8,4¢-oxyneolign-7¢-ene-7,9,9¢-triol 7,9¢-bis-O-β-D-glucopyranoside (1. In the in vitro assays, compound 1 and (--syringaresinol-4,4¢-bis-O-β-D-glucopyranoside (2 showed evident activity against glutamate-induced neurotoxicity in PC12 cells. Shashenoside I (4 showed a selective cytotoxic activity with the IC50 value of 4.17 μM against the acute myeloid leukemia cell line MV4-11, while it was inactive against 10 other human tumor cell lines.

  12. La salud reproductiva del varón amenazada

    Directory of Open Access Journals (Sweden)

    Marieta Fernández

    2014-01-01

    Comentario: El interés mostrado por la comunidad cientifica por esclarecer la realidad de la salud reproductiva en Europa y en otros países occidentales, ha con-ducido a la redacción de una serie de recomendaciones, propuestas por expertes en el campo, que sirvan de orientación para politicas de financiación de la investigación. El debate sobre el deteriora de la salud reproductiva delvarón europeo ha llegado a su fin. Ya nadie duda de que tante los parámetras de medida directa como los indicadores indirectes de la fertilidad masculina manifiestan ese daño. Lo que es realmente novedoso en la propuesta es, de una parte, la vinculación entre el deteriora en salud reproductiva -incluida la caída secular en los niveles de testosterona circulante del varón-y el riesgode enfermedad cardiovascular y diabetes; de otra parte, la presentación formal de una hipótesis etiológica que requiere la investigación de la exposición materno-infantil a contaminantes químicos con actividad hormonal y sugiere una actitud precautoria. Los disruptores endocrinos son componentes de cosméticos, detergentes, medicamentos y alimentes de consumo y u

  13. Acyl flavonoids, biflavones, and flavonoids from Cephalotaxus harringtonia var. nana.

    Science.gov (United States)

    Komoto, Noriko; Nakane, Takahisa; Matsumoto, Sachiko; Hashimoto, Shusuke; Shirota, Osamu; Sekita, Setsuko; Kuroyanagi, Masanori

    2015-10-01

    A methanol extract of the leaves of Cephalotaxus harringtonia var. nana and its ethyl acetate (EtOAc)-soluble fraction demonstrated strong antitumor activity against A549 and HT-29 cell lines. The EtOAc-soluble fraction was purified by column chromatography and high-performance liquid chromatography (HPLC) using a reverse-phase column to yield three novel acyl flavonoids and a biflavonoid, along with 15 other known compounds that included flavonoids, biflavonoids, and other phenolics. The structures of the new compounds were elucidated using spectral data from HR-MS and NMR, including two-dimensional NMR studies, as (2R,3R)-3-O-eicosanoyltaxifolin (1), (2R,3R)-3-O-docosanoyltaxifolin (2), (2R,3R)-3-O-tetracosanoyltaxifolin (3), and 6-methyl-4',7,7″-tri-O-methylamentoflavone (4). The isolated compounds, including the known compounds, were tested for possible antitumor activity; some of the biflavones were found to be active. The potent antitumor activity of the extract was attributed to Cephalotaxus alkaloids, such as homoharringtonine (20).

  14. Three New Clerodane Diterpenes from Polyalthia longifolia var. pendula

    Directory of Open Access Journals (Sweden)

    Tung-Ho Wu

    2014-02-01

    Full Text Available Three new clerodane diterpenes, (4→2-abeo-cleroda-2,13E-dien-2,14-dioic acid (1, (4→2-abeo-2,13-diformyl-cleroda-2,13E-dien-14-oic acid (2, and 16(R&S- methoxycleroda-4(18,13-dien-15,16-olide (3, were isolated from the unripe fruit of Polyalthia longifolia var. pendula (Annonaceae together with five known compounds (4–8. The structures of all isolates were determined by spectroscopic analysis. The anti-inflammatory activity of the isolates was evaluated by testing their inhibitory effect on NO production in LPS-stimulated RAW 264.7 macrophages. Among the isolated compounds, 16-hydroxycleroda-3,13-dien-15,16-olide (6 and 16-oxocleroda-3,13-dien-15-oic acid (7 showed promising NO inhibitory activity at 10 µg/mL, with 81.1% and 86.3%, inhibition, respectively.

  15. Embryological Studies on Narcissus tazetta var.chinensis

    Institute of Scientific and Technical Information of China (English)

    Ge Lili; Wu Jian; Chen Linjiao; Wang Rui; Tian Huiqiao

    2006-01-01

    Chinese narcissus (Narcissus tazetta var.chinensis Roem) blooms but has no seeds.Embryological studies on the species were conducted to discover the causes of its sterility.Its anther wall is composed of four layers of cells,and its tapetum is of the secretory type.The cytokinesis of microspore mother cells is of the successive type,and the tetrad is tetrahedral.During meiosis of microspore mother cells,some chromosomes lagged,and several micronuclei were found in tetrads.Only 27.7% of the pollen grains contained full cytoplasm,and 1.3% of them germinated in culture medium.No pollen grain,however,could germinate on the stigma.The ovary is trilocular with axile placenta,and the ovules are bitegmic,tenuinucellate,and anatropous.Its embryo sac is of the polygonum type.Most embryo sacs degenerated,and only about 4.5% of the ovules contained a normal embryo sac with an egg cell,two synergids,three antipodal,and a central cell containing two polar nuclei.One reason for the sterility of Chinese narcissus is the abnormality of microsporogenesis and megasporogenesis,in which only a few functional pollen grains and embryo sacs are produced.The other reason is that the pollen grains cannot germinate on the stigma.

  16. Ortopnea y hemoptisis en un varón joven

    Directory of Open Access Journals (Sweden)

    Jacobo Silva

    2005-04-01

    Full Text Available Varón de 21 años visitado en urgencias por ortopnea, hemoptisis y disnea. La radiografía detectó redistribución en hemitórax izquierdo, el ecocardiograma una masa intraauricular izquierda que protruía en el ventrículo izquierdo a través de la válvula mitral, produciendo obstrucción crítica, y la tomografía computarizada (TC una masa que ocupaba la aurícula izquierda desde la vena pulmonar superior izquierda (Fig. 1. Por vía transeptal superior se reseca una masa multilobulada de 6 × 7 cm, con base de implantación en el techo auricular (Fig. 2, que se reconstruyó con pericardio autólogo. La histopatología confirma el diagnóstico de leiomiosarcoma de vena pulmonar muy diferenciado. Al paciente se le dio el alta a los siete días.

  17. Two New Flavonol Glycosides from Sarcopyramis bodinieri var. delicate

    Directory of Open Access Journals (Sweden)

    Yan Qiu

    2008-06-01

    Full Text Available Detailed chemical investigation of the herb Sarcopyramis bodinieri var. delicate resulted in the isolation of two new flavonol glycosides, namely, isorhamnetin-3-O-(6′′-OE- feruloyl-β-D-glucopyranoside (1 and isorhamnetin-3-O-(6′′-O-E-feruloyl-β-Dgalactopyranoside (2. In addition, four known compounds, quercetin-3-O-(6′′-acetyl-β-Dglucopyranoside (3, isorhamnetin-3-O-(6′′-acetyl-β-D-glucopyranoside (4, quercetin-3- O-(6′′-O-E-p-coumaroyl-β-D-glucopyranoside (5, and isorhamnetin-3-O-(6′′-O-E-pcoumaroyl- β-D-glucopyranoside (6 were obtained. The structures of the new isolates were determined by extensive spectroscopic analysis.

  18. Antioxidant properties of European cranberrybush fruit (Viburnum opulus var. edule).

    Science.gov (United States)

    Rop, Otakar; Reznicek, Vojtech; Valsikova, Magdalena; Jurikova, Tunde; Mlcek, Jiri; Kramarova, Daniela

    2010-06-23

    In the literature there is little available information concerning European cranberrybush fruit (Viburnum opulus var. edule). This plant can be cultivated, even in harsh climatic conditions, because of its low environmental demands, and it is possible to harvest the fruit even in the snow cover. The aim of this study was to determine the content of polyphenolics, antioxidant activity, flavonoids and vitamin C in the fruit of three cultivars Leningradskaya otbornaya , Souzga and Taezny rubiny of this species. In the case of polyphenolics, high contents [up to 8.29 g of gallic acid/kg of fresh mass (FM)] were observed. The 1,1 -diphenyl-2-picrylhydrazyl (DPPH) and 2,2 -azinobis-3-ethyl-benzthiazino-6-sulphonic acid (ABTS) tests were applied to determine antioxidant activity, which was also high in comparison with other fruit species. The corresponding correlations between the polyphenolic content and antioxidant activity were in case of the DPPH test r(2) = 0.88 and for the ABTS test r(2) = 0.98. For comparison, the scavenging activity towards reactive oxygen species (superoxide anion, hydroxyl radical and nitric oxide) was determined by using a 25% fruit extract of particular cultivars. Antioxidant efficiency was also assessed using the rat liver slice model. Furthermore, the contents of flavonoids and vitamin C were assayed, giving values of 4.89 g/kg and 1.64 g/kg FM, respectively. The work should contribute to the popularization of this species as a promising crop plant in human nutrition.

  19. Neuroprotective Lignans from the Fruits of Schisandra bicolor var. tuberculata.

    Science.gov (United States)

    Liu, Ye; Yu, Heng-Yi; Wang, Yan-Mei; Tian, Tian; Wu, Wen-Ming; Zhou, Ming; Meng, Xiang-Gao; Ruan, Han-Li

    2017-04-28

    Nine new lignans (1-9) and ten known analogues (10-19) were isolated from the fruits of Schisandra bicolor var. tuberculata. The structures of compounds 1-9 were established on the basis of spectroscopic data analysis. The absolute configuration of compound 1 was determined by single-crystal X-ray diffraction analysis with Cu Kα irradiation techniques, and the absolute configurations of compounds 2-9 were deduced by comparing their experimental ECD spectra and optical rotations with those of compound 1 or similar compounds. All isolates were evaluated for their neuroprotective activities against CoCl2, H2O2, and Aβ25-35-induced SH-SY5Y cell injury, and were found to exhibit different degrees of neuroprotective effects. At a low concentration of 3.2 nM, compounds 3, 8, 9, and 14-19 in CoCl2-induced, compounds 7, 8, 13, 17, and 18 in H2O2-induced, and compounds 2, 6, 7, 9, 10, and 12-19 in Aβ25-35-induced SH-SY5Y cell injury models, showed statistically significant neuroprotective activities, when compared with each negative control group.

  20. Exploring strategies for coupled 4D-Var data assimilation using an idealised atmosphere–ocean model

    Directory of Open Access Journals (Sweden)

    Polly J. Smith

    2015-07-01

    Full Text Available Operational forecasting centres are currently developing data assimilation systems for coupled atmosphere–ocean models. Strongly coupled assimilation, in which a single assimilation system is applied to a coupled model, presents significant technical and scientific challenges. Hence weakly coupled assimilation systems are being developed as a first step, in which the coupled model is used to compare the current state estimate with observations, but corrections to the atmosphere and ocean initial conditions are then calculated independently. In this paper, we provide a comprehensive description of the different coupled assimilation methodologies in the context of four-dimensional variational assimilation (4D-Var and use an idealised framework to assess the expected benefits of moving towards coupled data assimilation. We implement an incremental 4D-Var system within an idealised single-column atmosphere–ocean model. The system has the capability to run both strongly and weakly coupled assimilations as well as uncoupled atmosphere- or ocean-only assimilations, thus allowing a systematic comparison of the different strategies for treating the coupled data assimilation problem. We present results from a series of identical twin experiments devised to investigate the behaviour and sensitivities of the different approaches. Overall, our study demonstrates the potential benefits that may be expected from coupled data assimilation. When compared to uncoupled initialisation, coupled assimilation is able to produce more balanced initial analysis fields, thus reducing initialisation shock and its impact on the subsequent forecast. Single observation experiments demonstrate how coupled assimilation systems are able to pass information between the atmosphere and ocean and therefore use near-surface data to greater effect. We show that much of this benefit may also be gained from a weakly coupled assimilation system, but that this can be sensitive to the

  1. Intoxicação por Baccharis megapotamica var. weiriiem ovinos Spontaneous Baccharis megapotamica var. weirii poisoning in sheep

    Directory of Open Access Journals (Sweden)

    Pedro M.O. Pedroso

    2010-05-01

    Full Text Available As intoxicações por Baccharis coridifolia afetam especialmente animais de fazenda famintos ou curiosos e que não haviam tido contato prévio com a planta. B. coridifolia ocorre usualmente em terrenos secos de coxilhas no Rio Grande do Sul e estados ou países vizinhos. Uma forma indistinguível e esporádica da doença tem sido associada com a ingestão de Baccharis megapotamica que ocorre em áreas úmidas. Relata-se a intoxicação natural de quatro cordeiros após ingestão de Baccharis megapotamica var. weirii. A doença foi observada em uma propriedade localizada em Barra do Ribeiro, Rio Grande do Sul. O rebanho era composto por 220 ovinos, os quais eram mantidos em área de pastagem nativa sem qualquer suplementação. Uma rápida doença clínica caracterizada por anorexia, cólica, diarréia e desidratação causou a morte de três cordeiros em um período de 8 a 24 horas, o outro foi encontrado morto. A necropsia revelou alterações significativas no rúmen, no qual havia edema de serosa e hemorragias equimóticas na submucosa. Microscopicamente, o rúmen apresentou edema de submucosa, além de edema, tumefação, vacuolização e necrose de mucosa. O diagnóstico foi fundamentado nos achados clínicos, patológicos e epidemiológicos.Spontaneous poisoning of livestock by Baccharis coridifolia affects mostly hungry or curious animals that have not entered in contact with the plant previously. The plant occurs usually in dried hilly soils of Rio Grande do Sul and neighboring states or countries. An indistinguishable and sporadic form of the disease has been associated with the ingestion of Baccharis megapotamica, a species occurring in moist areas. This communication reports the spontaneous poisoning of four lambs after ingestion of B. megapotamica var. weirii. Clinical signs were observed in three lambs, the other was found dead. A rapid clinical disease characterized by anorexia, colic, dehydration, and diarrhea resulted in death

  2. Variational principles

    CERN Document Server

    Moiseiwitsch, B L

    2004-01-01

    This graduate-level text's primary objective is to demonstrate the expression of the equations of the various branches of mathematical physics in the succinct and elegant form of variational principles (and thereby illuminate their interrelationship). Its related intentions are to show how variational principles may be employed to determine the discrete eigenvalues for stationary state problems and to illustrate how to find the values of quantities (such as the phase shifts) that arise in the theory of scattering. Chapter-by-chapter treatment consists of analytical dynamics; optics, wave mecha

  3. Genomic signatures of strain selection and enhancement in Bacillus atrophaeus var. globigii, a historical biowarfare simulant.

    Directory of Open Access Journals (Sweden)

    Henry S Gibbons

    Full Text Available BACKGROUND: Despite the decades-long use of Bacillus atrophaeus var. globigii (BG as a simulant for biological warfare (BW agents, knowledge of its genome composition is limited. Furthermore, the ability to differentiate signatures of deliberate adaptation and selection from natural variation is lacking for most bacterial agents. We characterized a lineage of BGwith a long history of use as a simulant for BW operations, focusing on classical bacteriological markers, metabolic profiling and whole-genome shotgun sequencing (WGS. RESULTS: Archival strains and two "present day" type strains were compared to simulant strains on different laboratory media. Several of the samples produced multiple colony morphotypes that differed from that of an archival isolate. To trace the microevolutionary history of these isolates, we obtained WGS data for several archival and present-day strains and morphotypes. Bacillus-wide phylogenetic analysis identified B. subtilis as the nearest neighbor to B. atrophaeus. The genome of B. atrophaeus is, on average, 86% identical to B. subtilis on the nucleotide level. WGS of variants revealed that several strains were mixed but highly related populations and uncovered a progressive accumulation of mutations among the "military" isolates. Metabolic profiling and microscopic examination of bacterial cultures revealed enhanced growth of "military" isolates on lactate-containing media, and showed that the "military" strains exhibited a hypersporulating phenotype. CONCLUSIONS: Our analysis revealed the genomic and phenotypic signatures of strain adaptation and deliberate selection for traits that were desirable in a simulant organism. Together, these results demonstrate the power of whole-genome and modern systems-level approaches to characterize microbial lineages to develop and validate forensic markers for strain discrimination and reveal signatures of deliberate adaptation.

  4. Effect of 2,4diacetylphloroglucinol of Pythium: cellular responses and variation in sensitivity among propagules and species

    NARCIS (Netherlands)

    Souza, J.T.; Arnould, C.; Deulvot, C.; Lemanceau, P.; Gianinazzi-Pearson, V.; Raaijmakers, J.M.

    2003-01-01

    The antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) plays an important role in the suppression of plant pathogens by several strains of Pseudomonas spp. Based on the results of this study, there is variation within and among Pythium spp. to 2,4-DAPG. Also, various propagules of Pythium ultimum var.

  5. The Many Faces of Human Leukocyte Antigen-G

    DEFF Research Database (Denmark)

    Dahl, Mette; Djurisic, Snezana; Hviid, Thomas Vauvert F

    2014-01-01

    is the human leukocyte antigen (HLA)-G, a nonclassical HLA protein displaying limited polymorphism, restricted tissue distribution, and a unique alternative splice pattern. HLA-G is primarily expressed in placenta and plays multifaceted roles during pregnancy, both as a soluble and a membrane-bound molecule...... pregnancy and pregnancy complications, such as preeclampsia, recurrent spontaneous abortions, and subfertility or infertility. This review aims to clarify the multifunctional role of HLA-G in pregnancy-related disorders by focusing on genetic variation, differences in mRNA stability between HLA-G alleles...

  6. [Infectious hepatitis. I. Presence of HBs antigen].

    Science.gov (United States)

    Calderón, E; Ridaura, C; Legorreta, J; Gómez, D; Ruiz, M; Kassian, A

    1975-01-01

    A prospective study in 268 patients of different pediatric ages affected with icteric hepatitis is presented, with a longitudinal follow-up of one year minimum. Different types of clinical evolution are described and related to the presence of HBs antigen. In 34 of the 268 patients HBs antigen was positive; in 20 of 28 patients with acute and long evolution, positivity of the antigen was transitory with an average of 46 days; in the remaining 8 of 28 patients it extended from 6 months to less than 2 years. The presence of HBs antigen is a risk that may be correlated with the tendency to extend the prolonged.

  7. [Antigenic relationships between Debaryomyces strains (author's transl)].

    Science.gov (United States)

    Aksoycan, N

    1980-01-01

    The results of the agglutinations between homologous and heterologous Debaryomyces strains and their agglutinating sera are shown in table I. According to these findings, D. hansenii and D. marama are antigenically different from other Debaryomyces strains in this genus. In a previous study Aksoycan et al. have shown a common antigenic factor between D. hansenii, D. marama strains and Salmonella 0:7 antigen. This factor was not present in other six strains of Debaryomyces. These results also show that D. tamarii does not have any antigenic relationship with the other seven species of Debaryomyces in this genus.

  8. Consequences of stoichiometric error on nuclear DNA content evaluation in Coffea liberica var. dewevrei using DAPI and propidium iodide.

    Science.gov (United States)

    Noirot, Michel; Barre, Philippe; Louarn, Jacques; Duperray, Christophe; Hamon, Serge

    2002-04-01

    The genome size of coffee trees (Coffea sp.) was assessed using flow cytometry. Nuclear DNA was stained with two dyes [4',6-diamino-2-phenylindole dihydrochloride hydrate (DAPI) and propidium iodide (PI)]. Fluorescence in coffee tree nuclei (C-PI or C-DAPI) was compared with that of the standard, petunia (P-PI or P-DAPI). If there is no stoichiometric error, then the ratio between fluorescence of the target nuclei and that of the standard nuclei (R-PI or R-DAPI) is expected to be proportional to the genome size. Between-tree differences in target : standard fluorescence ratios were noted in Coffea liberica var. dewevrei using propidium iodide and DAPI. For both dyes, between-tree differences were due to a lack of proportionality when comparing locations of the coffee peak and the petunia peak. Intraspecific genome size variations clearly cannot explain variations in the target : standard fluorescence ratio. The origin of the lack of proportionality between target and standard fluorescences differed for the two dyes. With propidium iodide, there was a regression line convergence point, and no between-tree differences were noted in this respect, whereas there was no such convergence with DAPI. An accurate estimate of genome size can thus be obtained with PI. Implications with respect to accessibility and binding mode are discussed.

  9. Effects of seasonal variations on antioxidant activity of pink guava fruits

    Science.gov (United States)

    Ahmad, Haniza; Abdullah, Aminah

    2014-09-01

    This study aimed to evaluate the effects of seasonal variations during rainy and hot season on antioxidant activity of pink guava fruits in approximately one year duration specifically on November 2012, December 2012, January 2013, March 2013, April 2013, May 2013, July 2013, August 2013 and November 2013. Fruit samples (Sungkai and Semenyih variants) were collected from Sime Darby Beverages plantation located in Sitiawan. The fruits were samples for 9 times from Nov 2012 to Nov 2013 except Feb 2013, Jun 2013, Sept 2013 and Oct 2013. Fruits were peeled, seeded and blended into uniform puree. Samples were then extracted for its antioxidant activity determination using 50% acetone. Antioxidant activity was evaluated using total phenolic compounds (TPC) assay, ferric-reducing antioxidant power assay (FRAP) and 1,1-diphenyl1-2-picrylhydrazyl free radical-scavenging capacity (DPPH). Analysis was conducted using 96-well microplate spectrophotometer UV. The highest TPC result was Semenyih var recorded 2192.80 mg GAE/100g FW whilst Sungkai var 1595.98 mg GAE/100g FW both on July 2013 with rainfall was at the least (45mm) and the lowest for Sungkai var was 792.75 mg GAE/100g FW and 1032.41 mg GAE/100g FW for Semenyih var, both on Nov 2012 with 185mm rainfall. There were significant negative correlation between TPC and rainfall (mm) for both Semenyih var (r = - 0.699, p<0.005, r2 = 0.489) and Sungkai var (r = -0.72, p<0.05, r2 = 0.531). The highest FRAP result (mg TE/100g FW) was 1677.74 for Semenyih var (Aug 2013, rainfall = 160.5mm) and the highest FRAP for Sungkai var was 1104.60 (Jul 2013, rainfall = 45.0mm) whereas the lowest for Semenyih and Sungkai var was 1090.22 (Mar 2013, rainfall = 97.5mm) and 767.88 (Nov 2012, rainfall = 185.50) respectively. There was weak negative correlation between FRAP and rainfall(mm) for both Sungkai var (r = - 0.324, p<0.05, r2 = 0.105) and Semenyih var (r = - 0.362, p<0.05, r2 = 0.132). The highest DPPH for Semenyih var was 88.40% (Aug

  10. Alastrim, varíola é? Is allastrim small pox?

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Teixeira

    2000-06-01

    Full Text Available Este artigo trata de uma controvérsia científica havida em São Paulo entre 1910 e 1913, que opôs dois destacados médicos da cidade: Antonio Carini, diretor do Instituto Pasteur de São Paulo, e Emílio Ribas, diretor do Serviço Sanitário. A questão em jogo era a classificação de uma doença que reinava no estado. Para Carini tratava-se de varíola, para Ribas era uma entidade mórbida chamada de alastrim. A polêmica teve início na Sociedade de Medicina e Cirurgia e, posteriormente, migrou para outros fóruns, incorporando novos personagens. A apresentação e discussão dessa controvérsia objetiva contribuiu para a compreensão do processo de construção e estabilização de um consenso científico no campo das ciências biomédicas.Between 1910 and 1913, two renowned physicians in the city of São Paulo found themselves engaged in a scientific controversy regarding the classification of a disease then assailing the state. Antonio Carini, director of the Instituto Pasteur de São Paulo, believed the illness to be small pox, while Emílio Ribas, director of the Serviço Sanitário, claimed it was allastrim, or milk pox. The controversy started in the Sociedade de Medicina e Cirurgia but later migrated to other forums and came to incorporate other figures as well. This presentation and discussion of the polemic is meant as a contribution to our understanding of the process by which a scientific consensus is constructed and solidified within the field of the biomedical sciences.

  11. Neural cell protective compounds isolated from Phoenix hanceana var. formosana.

    Science.gov (United States)

    Lin, Yi-Pei; Chen, Tai-Yuan; Tseng, Hsiang-Wen; Lee, Mei-Hsien; Chen, Shui-Tein

    2009-06-01

    A platform for screening drugs for their ability to protect neuronal cells against cytotoxicity was developed. Nerve growth factor (NGF) differentiates PC12 cells into nerves, and these differentiated PC12 cells enter apoptosis when challenged with 6-hydroxydopamine (6-OHDA). A screening spectrophotometer was used to assay cytotoxicity in these cells; pretreatment with test samples allowed identification of compounds that protected against this neuronal cytotoxicity. The 95% ethanol extract of Phoenix hanceana Naudin var. formosana Beccari. (PH) showed potential neuroprotective activity in these assays. The PH ethanol extract was further fractionated by sequential partitioning with n-hexane, ethyl acetate (EtOAc), n-butanol (n-BuOH), and water. Subsequent rounds of assaying resulted in the isolation of ten constituents, and their structures were characterized by various spectroscopic techniques and identified by comparison with previous data as: isoorientin (1), isovitexin (2), veronicastroside (3), luteolin-7-O-beta-d-glucopyranoside (4), isoquercitrin (5), tricin-7-neohesperidoside (6), tricin-7-O-beta-d-gluco-pyranoside (7), (+)-catechin (8), (-)-epicatechin (9), and orientin 7-O-beta-d-glucopyranoside (10). Among these compounds, isovitexin (2), luteolin-7-O-beta-d-glucopyranoside (4) and (+)-catechin (8) showed significant neuroprotective activity in cell viability (WST-8 reduction), anti-apoptosis (Annexin V-FITC/propidium iodide double-labeled flow cytometry), and cellular ROS scavenging assays (besides isovitexin (2)), as well as a decreased caspase-8 activity in 6-OHDA-induced PC12 cells. Hence, isovitexin (2), luteolin-7-O-beta-d-glucopyranoside (4), and (+)-catechin (8) protected PC12 cells from 6-OHDA-induced apoptotic neurotoxicity.

  12. Chemical Constituents from Solanum glabratum Dunal var. sepicula

    Directory of Open Access Journals (Sweden)

    Essam Abdel-Sattar

    2015-01-01

    Full Text Available In the course of screening program of Saudi plants for their potential biological activity, the methanolic extract of Solanum glabratum Dunal var. sepicula as well as its different fractions were tested for its possible cytoxicity in prostate cancer (PC3 and colon cancer (HT29 cell lines using the MTT assay. In the present study, three spirostan saponins and one flavonoid glycoside were isolated from the active n-butanol fraction through a bio-guided fractionation approach. Two new saponin glycosides were identified as 23-β-D-glucopyranosyl (23S, 25R-spirost-5-en-3, 23 diol 3-O-α-L-rhamnopyranosyl-(1→2-O-[α-L-rhamnopyranosyl-(1→4]-β-D-glucopyranoside (2 and (25R-spirost-5-en-3-ol 3-O-α-L-rhamnopyranosyl-(1→2-O-[β-D-glucopyranosyl-(1→3]-β-D-galactopyranoside (3. In addition, two known compounds were also isolated and identified as isorhamnetin-3-O-α-L-rhamnopyranosyl (1→6 β-D-glucopyranoside (1 and (23S, 25R-spirost-5-en-3, 23 diol 3-O-α-L-rhamnopyranosyl-(1→2-O-[α-L-rhamnopyranosyl-(1→4]-β-D-glucopyranoside (4. The structures of the isolated compounds were elucidated based on their MS, one dimensional and extensive two dimensional NMR spectral data. Among the isolated metabolites, compound 3 showed the highest cytotoxic activity in both PC3 and HT29 cell lines with an IC 50 values of 14.8 and 19.5 m g/mL, respectively.

  13. Antioxidant Properties of European Cranberrybush Fruit (Viburnum opulus var. edule

    Directory of Open Access Journals (Sweden)

    Otakar Rop

    2010-06-01

    Full Text Available In the literature there is little available information concerning European cranberrybush fruit (Viburnum opulus var. edule. This plant can be cultivated, even in harsh climatic conditions, because of its low environmental demands, and it is possible to harvest the fruit even in the snow cover. The aim of this study was to determine the content of polyphenolics, antioxidant activity, flavonoids and vitamin C in the fruit of three cultivars ´Leningradskaya otbornaya´, ´Souzga´ and ´Taezny rubiny´ of this species. In the case of polyphenolics, high contents [up to 8.29 g of gallic acid/kg of fresh mass (FM] were observed. The 1,1´-diphenyl-2-picrylhydrazyl (DPPH and 2,2´-azinobis-3-ethyl-benzthiazino-6-sulphonic acid (ABTS tests were applied to determine antioxidant activity, which was also high in comparison with other fruit species. The corresponding correlations between the polyphenolic content and antioxidant activity were in case of the DPPH test r2 = 0.88 and for the ABTS test r2 = 0.98. For comparison, the scavenging activity towards reactive oxygen species (superoxide anion, hydroxyl radical and nitric oxide was determined by using a 25% fruit extract of particular cultivars. Antioxidant efficiency was also assessed using the rat liver slice model. Furthermore, the contents of flavonoids and vitamin C were assayed, giving values of 4.89 g/kg and 1.64 g/kg FM, respectively. The work should contribute to the popularization of this species as a promising crop plant in human nutrition.

  14. Indolizidine, antiinfective and antiparasitic compounds from Prosopis glandulosa var. glandulosa.

    Science.gov (United States)

    Samoylenko, Volodymyr; Ashfaq, Mohammad K; Jacob, Melissa R; Tekwani, Babu L; Khan, Shabana I; Manly, Susan P; Joshi, Vaishali C; Walker, Larry A; Muhammad, Ilias

    2009-01-01

    A new potent antiinfective and antiparasitic 2,3-dihydro-1H-indolizinium chloride (1) was isolated from Prosopis glandulosa var. glandulosa. Three additional new (2-4) and one known (5) indolizidines were also isolated, and the dihydrochloride salts of 1-3 (compounds 6, 7, and 8) were prepared. Structures were determined by 1D and 2D NMR and mass spectra. Compound 1 showed potent in vitro antifungal activity against Cryptococcus neoformans and Aspergillus fumigatus (IC(50) values = 0.4 and 3.0 microg/mL, respectively) and antibacterial activity against methicillin-resistant Staphylococcus aureus and Mycobacterium intracellulare (IC(50) values of 0.35 and 0.9 microg/mL, respectively). The remarkable in vitro fungicidal activity of 1-4 against C. neoformans (MFCs = 0.63-1.25 microg/mL) and 2, 3, and 5 against A. fumigatus (MFCs = 0.63-2.5 microg/mL) were similar to amphotericin B, but >2-4-fold more potent than 6-8. Prosopilosidine (1) showed potent in vivo activity at 0.0625 mg/kg/day/ip for 5 days in a murine model of cryptococcosis by eliminating approximately 76% of C. neoformans infection from brain tissue compared to approximately 83% with amphotericin B at 1.5 mg/kg/day. Compounds 1 and 4 exhibited potent activity and high selectivity index (SI) values against chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum, with IC(50) values of 39 and 95 ng/mL and 42 and 120 ng/mL, respectively (chloroquine, IC(50) = 17 and 140 ng/mL). Prosopilosine (1) also showed in vivo antimalarial activity, with an ED(50) value of approximately 2 mg/kg/day/ip against Plasmodium berghei-infected mice after 3 days of treatment.

  15. New Data on Vaccine Antigen Deficient Bordetella pertussis Isolates

    Directory of Open Access Journals (Sweden)

    Valérie Bouchez

    2015-09-01

    Full Text Available Evolution of Bordetella pertussis is driven by natural and vaccine pressures. Isolates circulating in regions with high vaccination coverage present multiple allelic and antigenic variations as compared to isolates collected before introduction of vaccination. Furthermore, during the last epidemics reported in regions using pertussis acellular vaccines, isolates deficient for vaccine antigens, such as pertactin (PRN, were reported to reach high proportions of circulating isolates. More sporadic filamentous hemagglutinin (FHA or pertussis toxin (PT deficient isolates were also collected. The whole genome of some recent French isolates, deficient or non-deficient in vaccine antigens, were analyzed. Transcription profiles of the expression of the main virulence factors were also compared. The invasive phenotype in an in vitro human tracheal epithelial (HTE cell model of infection was evaluated. Our genomic analysis focused on SNPs related to virulence genes known to be more likely to present allelic polymorphism. Transcriptomic data indicated that isolates circulating since the introduction of pertussis vaccines present lower transcription levels of the main virulence genes than the isolates of the pre-vaccine era. Furthermore, isolates not producing FHA present significantly higher expression levels of the entire set of genes tested. Finally, we observed that recent isolates are more invasive in HTE cells when compared to the reference strain, but no multiplication occurs within cells.

  16. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  17. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  18. VarR controls colonization and virulence in the marine macroalgal pathogen Nautella italica R11

    Directory of Open Access Journals (Sweden)

    Melissa eGardiner

    2015-10-01

    Full Text Available There is increasing evidence to suggest that macroalgae (seaweeds are susceptible to infectious disease. However, to date, little is known about the mechanisms that facilitate the colonization and virulence of microbial seaweed pathogens. One well-described example of a seaweed disease is the bleaching of the red alga Delisea pulchra, which can be caused by the bacterium Nautella italica R11, a member of the Roseobacter clade. This pathogen contains a unique luxR-type gene, varR, which we hypothesize controls its colonization and virulence. We show here that a varR knock-out strain is deficient in its ability to cause disease in D. pulchra and is defective in biofilm formation and attachment to a common algal polysaccharide. Moreover complementation of the varR gene in trans can restore these functions to the wild type levels. Proteomic analysis of bacterial cells in planktonic and biofilm growth highlight the potential importance of nitrogen scavenging, mobilization of energy reserves, and stress resistance in the biofilm lifestyle of N. italica R11. Moreover, we show that VarR regulates the expression of a specific subset of biofilm-associated proteins. Taken together these data suggest that VarR controls colonization and persistence of N. italica R11 on the surface of a macroalgal host and that it is an important regulator of virulence.

  19. VarR controls colonization and virulence in the marine macroalgal pathogen Nautella italica R11.

    Science.gov (United States)

    Gardiner, Melissa; Fernandes, Neil D; Nowakowski, Dennis; Raftery, Mark; Kjelleberg, Staffan; Zhong, Ling; Thomas, Torsten; Egan, Suhelen

    2015-01-01

    There is increasing evidence to suggest that macroalgae (seaweeds) are susceptible to infectious disease. However, to date, little is known about the mechanisms that facilitate the colonization and virulence of microbial seaweed pathogens. One well-described example of a seaweed disease is the bleaching of the red alga Delisea pulchra, which can be caused by the bacterium Nautella italica R11, a member of the Roseobacter clade. This pathogen contains a unique luxR-type gene, varR, which we hypothesize controls its colonization and virulence. We show here that a varR knock-out strain is deficient in its ability to cause disease in D. pulchra and is defective in biofilm formation and attachment to a common algal polysaccharide. Moreover complementation of the varR gene in trans can restore these functions to the wild type levels. Proteomic analysis of bacterial cells in planktonic and biofilm growth highlight the potential importance of nitrogen scavenging, mobilization of energy reserves, and stress resistance in the biofilm lifestyle of N. italica R11. Moreover, we show that VarR regulates the expression of a specific subset of biofilm-associated proteins. Taken together these data suggest that VarR controls colonization and persistence of N. italica R11 on the surface of a macroalgal host and that it is an important regulator of virulence.

  20. Subcellular distribution and chemical forms of thorium in Brassica juncea var. foliosa.

    Science.gov (United States)

    Zhou, Sai; Kai, Hailu; Zha, Zhongyong; Fang, Zhendong; Wang, Dingna; Du, Liang; Zhang, Dong; Feng, Xiaojie; Jin, Yongdong; Xia, Chuanqin

    2016-06-01

    Brassica juncea var. foliosa (B. juncea var. foliosa) is a promising species for thorium (Th) phytoextraction due to its large biomass, fast growth rate and high tolerance toward Th. To further understand the mechanisms of Th tolerance, the present study investigated the subcellular distribution and chemical forms of Th found in B. juncea var. foliosa Our results indicated that in both roots and leaves, Th contents in different parts of the cells follow the order of cell wall > membranes and soluble fraction > organelles. In particular, Transmission Electron Microscope (TEM) analysis showed that Th was abundantly located in cell walls of the roots. Additionally, when plants were exposed to different concentrations of Th, we have found that Th existed in B. juncea var. foliosa with different chemical forms. Much of the Th extracted by 2% acetic acid (HAc), 1 M NaCl and HCl in roots with the percentage distribution varied from 47.2% to 62.5%, while in leaves, most of the Th was in the form of residue and the subdominant amount of Th was extracted by HCl, followed by 2% HAc. This suggested that Th compartmentation in cytosol and integration with phosphate or proteins in cell wall might be responsible for the tolerance of B. juncea var. foliosa to the stress of Th.