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Sample records for chitinase insertion domain

  1. Methyl jasmonate induces expression of a novel Brassica juncea chitinase with two chitin-binding domains.

    Science.gov (United States)

    Zhao, K J; Chye, M L

    1999-08-01

    We have cloned a 1.3 kb Brassica juncea cDNA encoding BjCHI1, a novel acidic chitinase with two chitin-binding domains that shows 62% identity to Nicotiana tabacum Chia1 chitinase. BjCHI1 is structurally unlike Chia1 that has one chitin-binding domain, but resembles Chia5 chitinase UDA1, the precursor of Urtica dioica agglutinin: however there is only 36.9% identity between them. We propose that BjCHI1 should be classified under a new class, Chia7. The spacer and the hinge region of BjCHI1 are proline-rich, like that of Beta vulgaris Ch1, a Chia6 chitinase with half a chitin-binding domain. Northern blot analysis showed that the 1.3 kb BjCHI1 mRNA is induced by wounding and methyljasmonate (MeJA) treatment but is unaffected by ethylene, salicylic acid (SA) or abscisic acid (ABA). This is the first report on MeJA induction of chitinase gene expression and further suggests that wound-related JA-mediated signal transduction is independent of that involving SA. Western blot analysis using polyclonal antibodies against BjCHI1 showed a cross-reacting band with an apparent molecular mass of 37 kDa in wounded tissues of B. juncea, revealing that, unlike UDA1, BjCHI1 is not cleaved post-translationally at the hinge. Expression of recombinant BjCHI1 in Escherichia coli BL21(DE3) inhibited its growth while crude extracts from E. coli JM109 expressing recombinant BjCHI1 showed chitinase activity. Results from polymerase chain reaction (PCR) suggest that genes encoding chitinases with single or double chitin-binding domains exist in B. juncea. PMID:10527425

  2. The N-terminal cysteine-rich domain of tobacco class I chitinase is essential for chitin binding but not for catalytic or antifungal activity.

    Science.gov (United States)

    Iseli, B; Boller, T; Neuhaus, J M

    1993-09-01

    The vacuolar chitinases of class I possess an N-terminal cysteine-rich domain homologous to hevein and chitin-binding lectins such as wheat germ agglutinin and Urtica dioica lectin. To investigate the significance of this domain for the biochemical and functional characteristics of chitinase, chimeric genes encoding the basic chitinase A of tobacco (Nicotiana tabacum) with and without this domain were constructed and constitutively expressed in transgenic Nicotiana sylvestris. The chitinases were subsequently isolated and purified to homogeneity from the transgenic plants. Chromatography on colloidal chitin revealed that only the form with the N-terminal domain, and not the one without it, had chitin-binding properties, demonstrating directly that the domain is a chitin-binding domain (CBD). Under standard assay conditions with radioactive colloidal chitin, both forms of chitinase had approximately the same catalytic activity. However, kinetic analysis demonstrated that the enzyme without CBD had a considerably lower apparent affinity for its substrate. The pH and temperature optima of the two chitinases were similar, but the form with the CBD had an approximately 3-fold higher activation energy and retained a higher activity at low pH values. Both chitinases were capable of inhibiting growth of Trichoderma viride, although the form with the CBD was about three times more effective than the one without it. Thus, the CBD is not necessary for catalytic or antifungal activity of chitinase. PMID:8208848

  3. Biochemistry of plant class IV chitinases and fungal chitinase-modifying proteins

    Science.gov (United States)

    Plant class IV chitinases have 2 domains, a small (3 kDa) amino-terminal domain with homology to carbohydrate binding peptides, and a larger (25 kDa) catalytic domain. The biological function of these chitinases is not known. But it is known that some pathogenic fungi secrete chitinase modifying pro...

  4. Lesion insertion in the projection domain: Methods and initial results

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baiyu; Leng, Shuai; Yu, Lifeng; Yu, Zhicong; Ma, Chi; McCollough, Cynthia, E-mail: mccollough.cynthia@mayo.edu [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2015-12-15

    Purpose: To perform task-based image quality assessment in CT, it is desirable to have a large number of realistic patient images with known diagnostic truth. One effective way of achieving this objective is to create hybrid images that combine patient images with inserted lesions. Because conventional hybrid images generated in the image domain fails to reflect the impact of scan and reconstruction parameters on lesion appearance, this study explored a projection-domain approach. Methods: Lesions were segmented from patient images and forward projected to acquire lesion projections. The forward-projection geometry was designed according to a commercial CT scanner and accommodated both axial and helical modes with various focal spot movement patterns. The energy employed by the commercial CT scanner for beam hardening correction was measured and used for the forward projection. The lesion projections were inserted into patient projections decoded from commercial CT projection data. The combined projections were formatted to match those of commercial CT raw data, loaded onto a commercial CT scanner, and reconstructed to create the hybrid images. Two validations were performed. First, to validate the accuracy of the forward-projection geometry, images were reconstructed from the forward projections of a virtual ACR phantom and compared to physically acquired ACR phantom images in terms of CT number accuracy and high-contrast resolution. Second, to validate the realism of the lesion in hybrid images, liver lesions were segmented from patient images and inserted back into the same patients, each at a new location specified by a radiologist. The inserted lesions were compared to the original lesions and visually assessed for realism by two experienced radiologists in a blinded fashion. Results: For the validation of the forward-projection geometry, the images reconstructed from the forward projections of the virtual ACR phantom were consistent with the images physically

  5. Insertion of tetracysteine motifs into dopamine transporter extracellular domains.

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    Deanna M Navaroli

    Full Text Available The neuronal dopamine transporter (DAT is a major determinant of extracellular dopamine (DA levels and is the primary target for a variety of addictive and therapeutic psychoactive drugs. DAT is acutely regulated by protein kinase C (PKC activation and amphetamine exposure, both of which modulate DAT surface expression by endocytic trafficking. In order to use live imaging approaches to study DAT endocytosis, methods are needed to exclusively label the DAT surface pool. The use of membrane impermeant, sulfonated biarsenic dyes holds potential as one such approach, and requires introduction of an extracellular tetracysteine motif (tetraCys; CCPGCC to facilitate dye binding. In the current study, we took advantage of intrinsic proline-glycine (Pro-Gly dipeptides encoded in predicted DAT extracellular domains to introduce tetraCys motifs into DAT extracellular loops 2, 3, and 4. [(3H]DA uptake studies, surface biotinylation and fluorescence microscopy in PC12 cells indicate that tetraCys insertion into the DAT second extracellular loop results in a functional transporter that maintains PKC-mediated downregulation. Introduction of tetraCys into extracellular loops 3 and 4 yielded DATs with severely compromised function that failed to mature and traffic to the cell surface. This is the first demonstration of successful introduction of a tetracysteine motif into a DAT extracellular domain, and may hold promise for use of biarsenic dyes in live DAT imaging studies.

  6. Co-evolution of chitinases from maize and other cereals with secreted proteases from Pleosporineae fungi

    Science.gov (United States)

    Plant class IV chitinases are composed of a carboxy-terminal chitinase domain that is attached, through a linker sequence, to a small amino-terminal domain that can be thought of as a structured peptide. While both the peptide-like domain and the chitinase domain share sequence homology throughout m...

  7. Structural and biophysical analysis of sequence insertions in the Venezuelan Equine Encephalitis Virus macro domain.

    Science.gov (United States)

    Guillén, Jaime; Lichière, Julie; Rabah, Nadia; Beitzel, Brett F; Canard, Bruno; Coutard, Bruno

    2015-04-01

    Random transposon insertions in viral genomes can be used to reveal genomic regions important for virus replication. We used these genomic data to evaluate at the protein level the effect of such insertions on the Venezuelan Equine Encephalitis Virus nsP3 macro domain. The structural analysis showed that transposon insertions occur mainly in loops connecting the secondary structure elements. Some of the insertions leading to a temperature sensitive viral phenotype (ts) are close to the cleavage site between nsP2 and nsP3 or the ADP-ribose binding site, two important functions of the macro domain. Using four mutants mimicking the transposon insertions, we confirmed that these insertions can affect the macro domain properties without disrupting the overall structure of the protein.

  8. Chitinases: An update

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    Rifat Hamid

    2013-01-01

    Full Text Available Chitin, the second most abundant polysaccharide in nature after cellulose, is found in the exoskeleton of insects, fungi, yeast, and algae, and in the internal structures of other vertebrates. Chitinases are enzymes that degrade chitin. Chitinases contribute to the generation of carbon and nitrogen in the ecosystem. Chitin and chitinolytic enzymes are gaining importance for their biotechnological applications, especially the chitinases exploited in agriculture fields to control pathogens. Chitinases have a use in human health care, especially in human diseases like asthma. Chitinases have wide-ranging applications including the preparation of pharmaceutically important chitooligosaccharides and N-acetyl D glucosamine, preparation of single-cell protein, isolation of protoplasts from fungi and yeast, control of pathogenic fungi, treatment of chitinous waste, mosquito control and morphogenesis, etc. In this review, the various types of chitinases and the chitinases found in different organisms such as bacteria, plants, fungi, and mammals are discussed.

  9. Latex-allergic patients sensitized to the major allergen hevein and hevein-like domains of class I chitinases show no increased frequency of latex-associated plant food allergy

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    Radauer, Christian; Adhami, Farzaneh; Fürtler, Irene; Wagner, Stefan; Allwardt, Dorothee; Scala, Enrico; Ebner, Christof; Hafner, Christine; Hemmer, Wolfgang; Mari, Adriano; Breiteneder, Heimo

    2011-01-01

    Allergies to certain fruits such as banana, avocado, chestnut and kiwi are described in 30–70% of latex-allergic patients. This association is attributed to the cross-reactivity between the major latex allergen hevein and hevein-like domains (HLDs) from fruit class I chitinases. We aimed to assess the extent of cross-reactivity between hevein and HLDs using sera from latex-allergic patients with and without plant food allergy. Hevein and HLDs of latex, banana, and avocado chitinases were expressed in Escherichia coli as fusion proteins with the maltose-binding protein and purified by affinity chromatography. IgE binding to these proteins was studied in sera from 59 latex-allergic patients and 20 banana-allergic patients without latex allergy by ELISA and ELISA inhibition. Additionally, 16,408 allergic patients’ sera were tested for IgE binding to hevein, latex chitinase, and wheat germ agglutinin using an allergen microarray. Hevein-specific IgE was detected in 34/59 (58%) latex-allergic patients’ sera. HLDs of latex, banana, and avocado chitinases were recognized by 21 (36%), 20 (34%), and 9 (15%) sera, respectively. In contrast, only one of 20 banana-allergic patients without latex allergy was sensitized to chitinase HLDs. In most tested latex-allergic patients’ sera, IgE binding to hevein was only partially reduced by preincubation with HLDs. Among hevein-sensitized, latex-allergic patients, the percentage of plant food allergy (15/34 = 44%) was equal to latex-allergic patients without hevein sensitization (11/25 = 44%). In the general allergic population, 230 of 16,408 sera (1.4%) reacted to hevein and/or a hevein-like allergen. Of these, 128 sera showed an isolated sensitization to hevein, whereas only 17 bound to latex chitinase or wheat germ agglutinin without hevein sensitization. In conclusion, the IgE response to HLDs is elicited by hevein as sensitizing allergen in most cases. Despite considerable cross-reactivity between these allergens, no

  10. Evaluation of a projection-domain lung nodule insertion technique in thoracic CT

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    Ma, Chi; Chen, Baiyu; Koo, Chi Wan; Takahashi, Edwin A.; Fletcher, Joel G.; McCollough, Cynthia H.; Levin, David L.; Kuzo, Ronald S.; Viers, Lyndsay D.; Vincent Sheldon, Stephanie A.; Leng, Shuai; Yu, Lifeng

    2016-04-01

    Task-based assessment of computed tomography (CT) image quality requires a large number of cases with ground truth. Inserting lesions into existing cases to simulate positive cases is a promising alternative approach. The aim of this study was to evaluate a recently-developed raw-data based lesion insertion technique in thoracic CT. Lung lesions were segmented from patient CT images, forward projected, and reinserted into the same patient CT projection data. In total, 32 nodules of various attenuations were segmented from 21 CT cases. Two experienced radiologists and 2 residents blinded to the process independently evaluated these inserted nodules in two sub-studies. First, the 32 inserted and the 32 original nodules were presented in a randomized order and each received a rating score from 1 to 10 (1=absolutely artificial to 10=absolutely realistic). Second, the inserted and the corresponding original lesions were presented side-by-side to each reader, who identified the inserted lesion and provided a confidence score (1=no confidence to 5=completely certain). For the randomized evaluation, discrimination of real versus artificial nodules was poor with areas under the receiver operative characteristic curves being 0.69 (95% CI: 0.58-0.78), 0.57 (95% CI: 0.46-0.68), and 0.62 (95% CI: 0.54-0.69) for the 2 radiologists, 2 residents, and all 4 readers, respectively. For the side-by-side evaluation, although all 4 readers correctly identified inserted lesions in 103/128 pairs, the confidence score was moderate (2.6). Our projection-domain based lung nodule insertion technique provides a robust method to artificially generate clinical cases that prove to be difficult to differentiate from real cases.

  11. Characterization of a novel chitinase from a moderately halophilic bacterium, Virgibacillus marismortui strain M3-23

    OpenAIRE

    Essghaier, Badiaa; Hedi, Abdeljabbar; Bajji, Mohammed; Jijakli, Haissam; Boudabous, Abdellatif; Sadfi-Zouaoui, Najla

    2012-01-01

    A new chitinase produced by the moderately halophilic bacterium Virgibacillus marismortui strain M3- 23 was identified and characterized. Distinguishable characteristics of high activity and stability at different pH, temperatures and salinity of M3-23 chitinase are reported. Analysis of the catalytic domain sequence from the enzyme highlighted its relationship to glycosyl hydrolase family 18. Comparison of the deduced chitinase sequence from strain M3-23 to known chitinases from Bacillus spe...

  12. Stomach Chitinase from Japanese Sardine Sardinops melanostictus: Purification, Characterization, and Molecular Cloning of Chitinase Isozymes with a Long Linker.

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    Kawashima, Satoshi; Ikehata, Hiroki; Tada, Chihiro; Ogino, Tomohiro; Kakizaki, Hiromi; Ikeda, Mana; Fukushima, Hideto; Matsumiya, Masahiro

    2016-01-20

    Fish express two different chitinases, acidic fish chitinase-1 (AFCase-1) and acidic fish chitinase-2 (AFCase-2), in the stomach. AFCase-1 and AFCase-2 have different degradation patterns, as fish efficiently degrade chitin ingested as food. For a comparison with the enzymatic properties and the primary structures of chitinase isozymes obtained previously from the stomach of demersal fish, in this study, we purified chitinase isozymes from the stomach of Japanese sardine Sardinops melanostictus, a surface fish that feeds on plankton, characterized the properties of these isozymes, and cloned the cDNAs encoding chitinases. We also predicted 3D structure models using the primary structures of S. melanostictus stomach chitinases. Two chitinase isozymes, SmeChiA (45 kDa) and SmeChiB (56 kDa), were purified from the stomach of S. melanostictus. Moreover, two cDNAs, SmeChi-1 encoding SmeChiA, and SmeChi-2 encoding SmeChiB were cloned. The linker regions of the deduced amino acid sequences of SmeChi-1 and SmeChi-2 (SmeChi-1 and SmeChi-2) are the longest among the fish stomach chitinases. In the cleavage pattern groups toward short substrates and the phylogenetic tree analysis, SmeChi-1 and SmeChi-2 were classified into AFCase-1 and AFCase-2, respectively. SmeChi-1 and SmeChi-2 had catalytic domains that consisted of a TIM-barrel (β/α)₈-fold structure and a deep substrate-binding cleft. This is the first study showing the 3D structure models of fish stomach chitinases.

  13. Cloning, Expression and 3D Structure Prediction of Chitinase from Chitinolyticbacter meiyuanensis SYBC-H1

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    Hao, Zhikui; Wu, Hangui; Yang, Meiling; Chen, Jianjun; Xi, Limin; Zhao, Weijie; Yu, Jialin; Liu, Jiayang; Liao, Xiangru; Huang, Qingguo

    2016-01-01

    Two CHI genes from Chitinolyticbacter meiyuanensis SYBC-H1 encoding chitinases were identified and their protein 3D structures were predicted. According to the amino acid sequence alignment, CHI1 gene encoding 166 aa had a structural domain similar to the GH18 type II chitinase, and CHI2 gene encoding 383 aa had the same catalytic domain as the glycoside hydrolase family 19 chitinase. In this study, CHI2 chitinase were expressed in Escherichia coli BL21 cells, and this protein was purified by ammonium sulfate precipitation, DEAE-cellulose, and Sephadex G-100 chromatography. Optimal activity of CHI2 chitinase occurred at a temperature of 40 °C and a pH of 6.5. The presence of metal ions Fe3+, Fe2+, and Zn2+ inhibited CHI2 chitinase activity, while Na+ and K+ promoted its activity. Furthermore, the presence of EGTA, EDTA, and β-mercaptoethanol significantly increased the stability of CHI2 chitinase. The CHI2 chitinase was active with p-NP-GlcNAc, with the Km and Vm values of 23.0 µmol/L and 9.1 mM/min at a temperature of 37 °C, respectively. Additionally, the CHI2 chitinase was characterized as an N-acetyl glucosaminidase based on the hydrolysate from chitin. Overall, our results demonstrated CHI2 chitinase with remarkable biochemical properties is suitable for bioconversion of chitin waste. PMID:27240345

  14. Comparative genomic analysis of chitinase and chitinase-like genes in the African malaria mosquito (Anopheles gambiae.

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    Jianzhen Zhang

    Full Text Available Chitinase is an important enzyme responsible for chitin metabolism in a wide range of organisms including bacteria, yeasts and other fungi, nematodes and arthropods. However, current knowledge on chitinolytic enzymes, especially their structures, functions and regulation is very limited. In this study we have identified 20 chitinase and chitinase-like genes in the African malaria mosquito, Anopheles gambiae, through genome-wide searching and transcript profiling. We assigned these genes into eight different chitinase groupings (groups I-VIII. Domain analysis of their predicted proteins showed that all contained at least one catalytic domain. However, only seven (AgCht4, AgCht5-1, AgCht6, AgCht7, AgCht8, AgCht10 and AgCht23 displayed one or more chitin-binding domains. Analyses of stage- and tissue-specific gene expression revealed that most of these genes were expressed in larval stages. However, AgCht8 was mainly expressed in the pupal and adult stages. AgCht2 and AgCht12 were specifically expressed in the foregut, whereas AgCht13 was only expressed in the midgut. The high diversity and complexity of An. gambiae chitinase and chitinase-like genes suggest their diverse functions during different developmental stages and in different tissues of the insect. A comparative genomic analysis of these genes along with those present in Drosophila melanogaster, Tribolium castaneum and several other insect species led to a uniform classification and nomenclature of these genes. Our investigation also provided important information for conducting future studies on the functions of chitinase and chitinase-like genes in this important malaria vector and other species of arthropods.

  15. pH-Triggered Conformational Switching along the Membrane Insertion Pathway of the Diphtheria Toxin T-Domain

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    Alexey S. Ladokhin

    2013-08-01

    Full Text Available The translocation (T-domain plays a key role in the action of diphtheria toxin and is responsible for transferring the catalytic domain across the endosomal membrane into the cytosol in response to acidification. Deciphering the molecular mechanism of pH-dependent refolding and membrane insertion of the T-domain, which is considered to be a paradigm for cell entry of other bacterial toxins, reveals general physicochemical principles underlying membrane protein assembly and signaling on membrane interfaces. Structure-function studies along the T-domain insertion pathway have been affected by the presence of multiple conformations at the same time, which hinders the application of high-resolution structural techniques. Here, we review recent progress in structural, functional and thermodynamic studies of the T-domain archived using a combination of site-selective fluorescence labeling with an array of spectroscopic techniques and computer simulations. We also discuss the principles of conformational switching along the insertion pathway revealed by studies of a series of T-domain mutants with substitutions of histidine residues.

  16. STRUCTURAL FEATURES OF PLANT CHITINASES AND CHITIN-BINDING PROTEINS

    NARCIS (Netherlands)

    BEINTEMA, JJ

    1994-01-01

    Structural features of plant chitinases and chitin-binding proteins are discussed. Many of these proteins consist of multiple domains,of which the chitin-binding hevein domain is a predominant one. X-ray and NMR structures of representatives of the major classes of these proteins are available now,

  17. Kinase domain insert containing receptor promotor controlled suicide gene system kills human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Zong-Hai Huang; Wen-Yu Yang; Qi Cheng; Jing-Long Yu; Zhou Li; Zong-Yan Tong; Hui-Juan Song; Xiao-Yan Che

    2005-01-01

    AIM: To evaluate the killing effect of double suicide gene mediated by adenovirus and regulated under kinase domain insert containing receptor (KDR) promoter on human umbilical vein endothelial cells. METHODS: By PCR technology, human KDR promoter gene, Escherichia coli(E. coli) cytosine deaminase (CD) gene and the herpes simple virus-thymidine kinase (TK) gene were cloned. Plasmid pKDR-CDglyTK was constructed with them. Then, a recombinant adenoviral plasmid pAdKDRCDglyTK was constructed in a "two-step transformation protocol". The newly constructed plasmids were transfected to 293 packaging cells to grow adenoviruses, which were further propagated and purified. Human umbilical vein endothelial cells (HUVEC) were infected with a different multiplicity of infection (MOI) of resultant recombinant adenovirus, the infection rate was measured with the aid of (GFP) expression. Infected cells were cultured in culture media containing different concentrations of (GCV) and/or 5-(FC), and the killing effects were measured.RESULTS: Recombinant adenoviruses AdKDR-CDglyTK were successfully constructed, and they infected HUVEC cells efficiently. Our data indicated that the infection rate was relevant to MOI of recombinant adenoviruses. HUVEC cells infected with AdKDR-CDglyTK were highly sensitive to the prodrugs, their survival rate correlated to both the concentration of the prodrugs and the MOI of recombinant adenoviruses. Our data also indicated that the two prodrugs used in combination were much more effective on killing transgeneic cells than GCV or 5-FC used alone. CONCLUSION: Prodrug/KDR-CDglyTK system is effective on killing HUVEC cells, its killing effect correlates to the concentration of prodrugs and recombinant adenovirus' MOI. Combined use of the two prodrugs confers better killing effects on transgeneic cells.

  18. X-ray structure of tRNA pseudouridine synthase TruD reveals an inserted domain with a novel fold.

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    Ericsson, Ulrika B; Nordlund, Pär; Hallberg, B Martin

    2004-05-01

    Pseudouridine synthases catalyse the isomerisation of uridine to pseudouridine in structural RNA. The pseudouridine synthase TruD, that modifies U13 in tRNA, belongs to a recently identified and large family of pseudouridine synthases present in all kingdoms of life. We report here the crystal structure of Escherichia coli TruD at 2.0 A resolution. The structure reveals an overall V-shaped molecule with an RNA-binding cleft formed between two domains: a catalytic domain and an insertion domain. The catalytic domain has a fold similar to that of the catalytic domains of previously characterised pseudouridine synthases, whereas the insertion domain displays a novel fold.

  19. Higher-Resolution Structure of the Human Insulin Receptor Ectodomain: Multi-Modal Inclusion of the Insert Domain.

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    Croll, Tristan I; Smith, Brian J; Margetts, Mai B; Whittaker, Jonathan; Weiss, Michael A; Ward, Colin W; Lawrence, Michael C

    2016-03-01

    Insulin receptor (IR) signaling is critical to controlling nutrient uptake and metabolism. However, only a low-resolution (3.8 Å) structure currently exists for the IR ectodomain, with some segments ill-defined or unmodeled due to disorder. Here, we revise this structure using new diffraction data to 3.3 Å resolution that allow improved modeling of the N-linked glycans, the first and third fibronectin type III domains, and the insert domain. A novel haptic interactive molecular dynamics strategy was used to aid fitting to low-resolution electron density maps. The resulting model provides a foundation for investigation of structural transitions in IR upon ligand binding.

  20. Cloning of the Bacillus thuringiensis serovar sotto chitinase (Schi gene and characterization of its protein

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    Wan-Fang Zhong

    2005-12-01

    Full Text Available Chitinase plays a positive role in the pathogenicity of Bacillus thuringiensis to insect pests. We used touchdown PCR to clone the chitinase (Schi gene from Bacillus thuringiensis serovar sotto (Bt sotto chromosomal DNA. Our DNA sequencing analysis revealed that the Bt sotto Schi gene consists of an open reading frame (ORF of 2067 nucleotides with codes for the chitinase precursor. We also found that the putative promoter consensus sequences (the -35 and -10 regions of the Bt soto Schi gene are identical to those of the chiA71 gene from Bt Pakistani, the chiA74 gene from Bt kenyae and the ichi gene from Bt israelensis. The Schi chitinase precursor is 688 amino acids long with an estimated molecular mass of 75.75 kDa and a theoretical isoelectric point of 5.74, and contains four domains, which are, in sequence, a signal peptide, an N-terminal catalytic domain, a fibronectin type III like domain and a C-terminal chitin-binding domain. Sequence comparison and the evolutionary relationship of the Bt sotto Schi chitinase to other chitinase and chitinase-like proteins are also discussed.

  1. Characterization of a chitinase from the cellulolytic actinomycete Thermobifida fusca.

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    Gaber, Yasser; Mekasha, Sophanit; Vaaje-Kolstad, Gustav; Eijsink, Vincent G H; Fraaije, Marco W

    2016-09-01

    Thermobifida fusca is a well-known cellulose-degrading actinomycete, which produces various glycoside hydrolases for this purpose. However, despite the presence of putative chitinase genes in its genome, T. fusca has not been reported to grow on chitin as sole carbon source. In this study, a gene encoding a putative membrane-anchored GH18 chitinase (Tfu0868) from T. fusca has been cloned and overexpressed in Escherichia coli. The protein was produced as SUMO fusion protein and, upon removal of the SUMO domain, soluble pure TfChi18A was obtained with yields typically amounting to 150mg per litre of culture. The enzyme was found to be relatively thermostable (apparent Tm=57.5°C) but not particularly thermoactive, the optimum temperature being 40-45°C. TfChi18A bound to α- and β-chitin and degraded both these substrates. Interestingly, activity towards colloidal chitin was minimal and in this case, substrate inhibition was observed. TfChi18A also cleaved soluble chito-oligosaccharides and showed a clear preference for substrates having five sugars or more. While these results show that TfChi18A is a catalytically competent GH18 chitinase, the observed catalytic rates were low compared to those of well-studied GH18 chitinases. This suggests that TfChi18A is not a true chitinase and not likely to endow T. fusca with the ability to grow on chitin. PMID:27108953

  2. The zinc finger SET domain gene Prdm14 is overexpressed in lymphoblastic lymphomas with retroviral insertions at Evi32.

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    E J Dettman

    Full Text Available BACKGROUND: AKXD recombinant inbred strains of mice have proven to be very useful in the identification of potential oncogenes and tumor suppressors involved in the development of lymphoid and myeloid malignancies. In these tumors, the hematopoietic insertion of an active AKV murine leukemia virus (MuLV is associated with the onset of disease. Common sites of retroviral insertion (CIS identify genes causally associated with the development or initiation of lymphoma. METHODOLOGY: In the present study, we analyzed a previously uncharacterized CIS, Ecotropic Viral Integration Site 32 (Evi32, which is located on mouse chromosome 1. We analyzed candidate genes in the region to identify those involved in Evi32 mediated oncogenesis. RESULTS: Here we show that proviral insertion at Evi32 correlates with significant overexpression of a putative transcription factor, PR-domain containing 14 (Prdm14. Tumors with insertions at Evi32 are consistently lymphoid in nature. Prdm14 is normally expressed early in embryonic development with the highest expression in undifferentiated embryonic stem (ES cells. This study implicates Prdm14 as a proto-oncogene involved in lymphoblastic lymphoma formation.

  3. Higher-Resolution Structure of the Human Insulin Receptor Ectodomain: Multi-Modal Inclusion of the Insert Domain.

    Science.gov (United States)

    Croll, Tristan I; Smith, Brian J; Margetts, Mai B; Whittaker, Jonathan; Weiss, Michael A; Ward, Colin W; Lawrence, Michael C

    2016-03-01

    Insulin receptor (IR) signaling is critical to controlling nutrient uptake and metabolism. However, only a low-resolution (3.8 Å) structure currently exists for the IR ectodomain, with some segments ill-defined or unmodeled due to disorder. Here, we revise this structure using new diffraction data to 3.3 Å resolution that allow improved modeling of the N-linked glycans, the first and third fibronectin type III domains, and the insert domain. A novel haptic interactive molecular dynamics strategy was used to aid fitting to low-resolution electron density maps. The resulting model provides a foundation for investigation of structural transitions in IR upon ligand binding. PMID:26853939

  4. Amino substituted nitrogen heterocycle ureas as kinase insert domain containing receptor (KDR inhibitors: Performance of structure–activity relationship approaches

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    Hayriye Yilmaz

    2015-06-01

    Full Text Available A quantitative structure–activity relationship (QSAR study was performed on a set of amino-substituted nitrogen heterocyclic urea derivatives. Two novel approaches were applied: (1 the simplified molecular input-line entry systems (SMILES based optimal descriptors approach; and (2 the fragment-based simplex representation of molecular structure (SiRMS approach. Comparison with the classic scheme of building up the model and balance of correlation (BC for optimal descriptors approach shows that the BC scheme provides more robust predictions than the classic scheme for the considered pIC50 of the heterocyclic urea derivatives. Comparison of the SMILES-based optimal descriptors and SiRMS approaches has confirmed good performance of both techniques in prediction of kinase insert domain containing receptor (KDR inhibitory activity, expressed as a logarithm of inhibitory concentration (pIC50 of studied compounds.

  5. The gene for stinging nettle lectin (Urtica dioica agglutinin) encodes both a lectin and a chitinase.

    Science.gov (United States)

    Lerner, D R; Raikhel, N V

    1992-06-01

    Chitin-binding proteins are present in a wide range of plant species, including both monocots and dicots, even though these plants contain no chitin. To investigate the relationship between in vitro antifungal and insecticidal activities of chitin-binding proteins and their unknown endogenous functions, the stinging nettle lectin (Urtica dioica agglutinin, UDA) cDNA was cloned using a synthetic gene as the probe. The nettle lectin cDNA clone contained an open reading frame encoding 374 amino acids. Analysis of the deduced amino acid sequence revealed a 21-amino acid putative signal sequence and the 86 amino acids encoding the two chitin-binding domains of nettle lectin. These domains were fused to a 19-amino acid "spacer" domain and a 244-amino acid carboxyl extension with partial identity to a chitinase catalytic domain. The authenticity of the cDNA clone was confirmed by deduced amino acid sequence identity with sequence data obtained from tryptic digests, RNA gel blot, and polymerase chain reaction analyses. RNA gel blot analysis also showed the nettle lectin message was present primarily in rhizomes and inflorescence (with immature seeds) but not in leaves or stems. Chitinase enzymatic activity was found when the chitinase-like domain alone or the chitinase-like domain with the chitin-binding domains were expressed in Escherichia coli. This is the first example of a chitin-binding protein with both a duplication of the 43-amino acid chitin-binding domain and a fusion of the chitin-binding domains to a structurally unrelated domain, the chitinase domain. PMID:1375935

  6. Kinase domain insert containing receptor promoter controlled suicide gene system selectively kills human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Wen-Yu Yang; Zong-Hai Huang; Li-Jun Lin; Zhou Li; Jing-Long Yu; Hui-Juan Song; Yong Qian; Xiao-Yan Che

    2006-01-01

    AIM: To study the selective killing of human umbilical vein endothelial cells (HUVECs) by a double suicide gene under the regulation of a kinase domain insert containing receptor (KDR) promoter and mediated by an adenoviral gene vector.METHODS: Human KDR promoter was cloned by polymerase chain reaction (PCR), and two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were constructed according to a two-step transformation protocol. These two newly constructed plasmids were then transfected into 293 packaging cells to grow adenovirus, which were further multiplied and purified.HUVECs and LoVo cells were infected with either of the two resultant recombinant adenoviruses (AdKDR-CDglyTK and AdCMV-CDglyTK) respectively, and the infection rates were estimated by detection of green fluorescent protein (GFP) expression. Infected cells were cultured in culture media containing different concentrations of 5-fluorocytosine (5-FC) and ganciclovir (GCV), and the killing effects were measured.RESULTS: The two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were successfully constructed and transfected into 293 cells. The resultant recombinant adenoviruses infected cells caused similar infection rates; and the infected cells exhibited different sensitivity to the prodrugs: HUVECs infected with AdCMV-CDglyTK and LoVo cells infected with AdCMVCDglyTK were highly sensitive to the prodrugs, and HUVECs infected with AdKDR-CDglyTK were similarly sensitive but significantly more sensitive than the LoVo cells infected with AdKDR-CdglyTK (P<0.001).CONCLJSION: Selective killing of HUVECs may be achieved by gene transfer of double suicide gene under the regulation of the KDR promoter. This finding may provide an optional way to target gene therapy of malignant tumors by abrogation of tumor blood vessels.

  7. Toxoplasma gondii Chitinase Induces Macrophage Activation.

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    Fausto Almeida

    Full Text Available Toxoplasma gondii is an obligate intracellular protozoan parasite found worldwide that is able to chronically infect almost all vertebrate species, especially birds and mammalians. Chitinases are essential to various biological processes, and some pathogens rely on chitinases for successful parasitization. Here, we purified and characterized a chitinase from T. gondii. The enzyme, provisionally named Tg_chitinase, has a molecular mass of 13.7 kDa and exhibits a Km of 0.34 mM and a Vmax of 2.64. The optimal environmental conditions for enzymatic function were at pH 4.0 and 50 °C. Tg_chitinase was immunolocalized in the cytoplasm of highly virulent T. gondii RH strain tachyzoites, mainly at the apical extremity. Tg_chitinase induced macrophage activation as manifested by the production of high levels of pro-inflammatory cytokines, a pathogenic hallmark of T. gondii infection. In conclusion, to our knowledge, we describe for the first time a chitinase of T. gondii tachyzoites and provide evidence that this enzyme might influence the pathogenesis of T. gondii infection.

  8. Identification of a novel calcium binding motif based on the detection of sequence insertions in the animal peroxidase domain of bacterial proteins.

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    Saray Santamaría-Hernando

    Full Text Available Proteins of the animal heme peroxidase (ANP superfamily differ greatly in size since they have either one or two catalytic domains that match profile PS50292. The orf PP_2561 of Pseudomonas putida KT2440 that we have called PepA encodes a two-domain ANP. The alignment of these domains with those of PepA homologues revealed a variable number of insertions with the consensus G-x-D-G-x-x-[GN]-[TN]-x-D-D. This motif has also been detected in the structure of pseudopilin (pdb 3G20, where it was found to be involved in Ca(2+ coordination although a sequence analysis did not reveal the presence of any known calcium binding motifs in this protein. Isothermal titration calorimetry revealed that a peptide containing this consensus motif bound specifically calcium ions with affinities ranging between 33-79 µM depending on the pH. Microcalorimetric titrations of the purified N-terminal ANP-like domain of PepA revealed Ca(2+ binding with a K(D of 12 µM and stoichiometry of 1.25 calcium ions per protein monomer. This domain exhibited peroxidase activity after its reconstitution with heme. These data led to the definition of a novel calcium binding motif that we have termed PERCAL and which was abundantly present in animal peroxidase-like domains of bacterial proteins. Bacterial heme peroxidases thus possess two different types of calcium binding motifs, namely PERCAL and the related hemolysin type calcium binding motif, with the latter being located outside the catalytic domains and in their C-terminal end. A phylogenetic tree of ANP-like catalytic domains of bacterial proteins with PERCAL motifs, including single domain peroxidases, was divided into two major clusters, representing domains with and without PERCAL motif containing insertions. We have verified that the recently reported classification of bacterial heme peroxidases in two families (cd09819 and cd09821 is unrelated to these insertions. Sequences matching PERCAL were detected in all kingdoms of

  9. Different structure and mRNA expression of Entamoeba invadens chitinases in the encystation and excystation.

    Science.gov (United States)

    Makioka, Asao; Kumagai, Masahiro; Hiranuka, Kazushi; Kobayashi, Seiki; Takeuchi, Tsutomu

    2011-08-01

    Entamoeba histolytica forms chitin-walled cysts during encystation process, where formation of the cyst wall needs not only chitin synthase but also chitinase. During excystation, quadruplet amoebae emerge from the chitin-walled cysts by dissolving the wall, so that chitinase may be necessary for excystation process as well. There is, however, no report on chitinase expression during excystation. In this study, we used Entamoeba invadens, a reptilian amoeba, as a model for encystation and excystation of E. histolytica, and studied chitinase mRNA expression in those processes. Although expression of three E. invadens chitinases designated EiChit1, EiChit2, and EiChit3 during encystation has been reported, we identified another enzyme named as EiChit4 in the E. invadens genome database. Therefore, we investigated the primary structure and mRNA expression of these four chitinases of Ei in the excystation as well as the encystation by real-time reverse transcription polymerase chain reaction (RT-PCR). Like EiChit1, EiChit4 had an 8 × Cys chitin-binding domain (CBD) and a hydrophilic spacer between the CBD and catalytic domain, and was also closer to EiChit1 than EiChit2 and EiChit3 in the phylogenetic tree. During encystation, the expression of all four chitinases increased in the early phase; the increase in EiChit1 and EiChit4 was much higher than in EiChit2 and EiChit3. Then, the expression of all four chitinases sharply decreased in the later phase. In cysts, EiChit1 was most abundantly expressed and EiChit4 was at a lower level, while the expressions of EiChit2 and EiChit3 were virtually absent. Following the induction of excystation, mRNA levels of EiChit1 and EiChit4 in cysts 5 h after induction were significantly lower than those in cysts before induction, while those of EiChit2 and EiChit3 were remarkably higher than before induction. The mRNAs of only EiChit2 and EiChit3 remarkably increased when the excystation was induced in the presence of cytochalasin D

  10. Pulmonary cryptococcosis induces chitinase in the rat

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    Casadevall Arturo

    2008-05-01

    Full Text Available Abstract Background We previously demonstrated that chronic pulmonary infection with Cryptococcus neoformans results in enhanced allergic inflammation and airway hyperreactivity in a rat model. Because the cell wall of C. neoformans consists of chitin, and since acidic mammalian chitinase (AMCase has recently been implicated as a novel mediator of asthma, we sought to determine whether such infection induces chitinase activity and expression of AMCase in the rat. Methods We utilized a previously-established model of chronic C. neoformans pulmonary infection in the rat to analyze the activity, expression and localization of AMCase. Results Our studies indicate that intratracheal inoculation of C. neoformans induces chitinase activity within the lung and bronchoalveolar lavage fluid of infected rats. Chitinase activity is also elicited by pulmonary infection with other fungi (e.g. C. albicans, but not by the inoculation of dead organisms. Enhanced chitinase activity reflects increased AMCase expression by airway epithelial cells and alveolar macrophages. Systemic cryptococcosis is not associated with increased pulmonary chitinase activity or AMCase expression. Conclusion Our findings indicate a possible link between respiratory fungal infections, including C. neoformans, and asthma through the induction of AMCase.

  11. A simple, flexible and efficient PCR-fusion/Gateway cloning procedure for gene fusion, site-directed mutagenesis, short sequence insertion and domain deletions and swaps

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    Etchells J Peter

    2009-10-01

    Full Text Available Abstract Background The progress and completion of various plant genome sequencing projects has paved the way for diverse functional genomic studies that involve cloning, modification and subsequent expression of target genes. This requires flexible and efficient procedures for generating binary vectors containing: gene fusions, variants from site-directed mutagenesis, addition of protein tags together with domain swaps and deletions. Furthermore, efficient cloning procedures, ideally high throughput, are essential for pyramiding of multiple gene constructs. Results Here, we present a simple, flexible and efficient PCR-fusion/Gateway cloning procedure for construction of binary vectors for a range of gene fusions or variants with single or multiple nucleotide substitutions, short sequence insertions, domain deletions and swaps. Results from selected applications of the procedure which include ORF fusion, introduction of Cys>Ser mutations, insertion of StrepII tag sequence and domain swaps for Arabidopsis secondary cell wall AtCesA genes are demonstrated. Conclusion The PCR-fusion/Gateway cloning procedure described provides an elegant, simple and efficient solution for a wide range of diverse and complicated cloning tasks. Through streamlined cloning of sets of gene fusions and modification variants into binary vectors for systematic functional studies of gene families, our method allows for efficient utilization of the growing sequence and expression data.

  12. Co-transformation of canola by chimeric chitinase and tlp genes towards improving resistance to Sclerotinia sclerotiorum.

    Science.gov (United States)

    Aghazadeh, Rustam; Zamani, Mohammadreza; Motallebi, Mostafa; Moradyar, Mehdi; Moghadassi Jahromi, Zahra

    2016-09-01

    Canola (Brassica napus) plants were co-transformed with two pathogenesis-related protein genes expressing a Trichoderma atroviride chitinase with a chitin-binding domain (chimeric chitinase) and a thaumatin-like protein (tlp) from Oryza sativa conferring resistance to phytopatogenic fungi by Agrobacterium-mediated transformation. The putative transgenic plants were confirmed by PCR. After measuring the specific activity of the chimeric chitinase and glucanase activity for tlp genes, transgenic plants with high specific activity were selected for southern blot analysis to confirm the copy number of the genes. In vitro assays, the antifungal activity of crude extracted protein against Sclerotinia sclerotiorum showed that the inhibition percentage in double transgenic plants was between 55 and 62, whereas the inhibition percentage in single-gene transformants (chimeric chitinase) ranged from 35 to 45 percent. Importantly, in greenhouse conditions, the double transgenic plants showed significant resistance than the single-gene transformant and wild type plants. The results in T2 generation using the intact leaf inoculation method showed that the average lesion diameters were 10, 14.7 and 29 mm for the double transformant, single-gene transformant and non-transgenic plants, respectively. Combined expression of chimeric chitinase and tlp in transgenic plants showed significantly enhanced resistance against S. sclerotiorum than the one that express single-gene transformant plants. These results suggest that the co-expression of chimeric chitinase and tlp can confer enhanced disease resistance in canola plant. PMID:27430511

  13. Purification and Characterization of a Novel Thermostable Chitinase from Thermomyces lanuginosus SY2 and Cloning of Its Encoding Gene

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A novel thermostable extracellular chitinase was purified from the culture filtrate of Thermomyces lanuginosus SY2 by using diethylaminoethyl Sepharose chromatography and Phenyl-Sepharose chromatography. The molecular size of the purified chitinase was estimated to be 48 kDa by sodium dodeeyl sulfate-polyacrylamide gel electrophoresis. The chitinase exhibited optimum catalytic activity at pH 4.5 and 55℃. The enzyme was stable at 50℃, and its half-life time at 65℃ was 25 min. The thermostable chitinase was obtained with 60% of the full activity, when it was incubated in the buffer (pH 2.5). The enzyme showed the unique properties for thermostability and pH stability since it was one of the most thermostable ehitinases so far isolated in fungi. Ca2+, Ba2+, Na2+, and K+ enhanced the enzyme activity, whereas Fe2+, Ag+, Hg2+, and ethylene diamine tetraacetic acid caused obvious inhibition. The N-terminal amino acids were AQGYLSVQYFVNWAI. Degenerate primers based on the N-terminal sequences of purified chitinase and a cDNA fragment encoding the chitinase gene were obtained through reverse transcriptase-polymerase chain reaction amplieation. The RACE was used to generate full-length cDNA clones. The cDNA of chit contained an open reading frame of 1 326 bp encoding 442 amino acids. The gene chit has been registered in GenBank with accession number DQ092332. The alignment results of putative amino acid sequence showed the lower similarity to other chitinases in family-18 except for the catalytic domain containing two conserved motifs related with catalytic activity of chitinase.

  14. Aeromonas chitinase degrades chironomid egg masses.

    Science.gov (United States)

    Laviad, Sivan; Golan, Amnon; Shaked, Tamar; Vaizel-Ohayon, Dalit; Halpern, Malka; Pick, Elah

    2016-02-01

    Chironomids are freshwater insects that undergo a complete metamorphosis of four life stages. Chironomid egg masses can be degraded by Vibrio cholerae and some Aeromonas species. Egg mass degradation by V. cholerae requires haemagglutinin protease activity. Our aim was to identify the egg mass degrading (EMD) factor secreted by Aeromonas dhkanesis 3K1C15. Following the hypothesis that the EMD factor of A. dhkanesis is also a protease, secreted proteases were screened, but none of them proved to have the same properties as the EMD factor. Using conventional protein purification methods, we found that the active fraction included chitinases. We further confirmed chitin as a building block of the egg masses. Interestingly, by supplementing bacterial growth media with chitin, we observed unexpected EMD factor activity in Aeromonas isolates that initially were not able to degrade egg masses. Accordingly, we concluded that although strain 3K1C15 secretes chitinases constitutively, most Aeromonas strains secrete chitinases inductively. Induction of chitinases in nature presumably occurs when bacteria are attached to the egg mass habitat, in which chitin is abundant. Considering that chitinases are highly conserved across bacteria phyla, we assume that the role of this enzyme in the bacteria-insect interplay could be wider than is currently thought. PMID:26472256

  15. Two forms of the membrane-bound state of the first C2 domain (C2A) of synaptotagminⅠand calcium-triggered membrane insertion

    Institute of Scientific and Technical Information of China (English)

    HE Yuhong; LI Xianghui; WANG Fu; XUE Yi; SUI Senfang

    2003-01-01

    The synaptic vesicle protein synaptotagminⅠ (sytⅠ) is a vesicle trans membrane protein present in synaptic vesicles, which has been proposed as the Ca 2+ sensor that regulates secretion. The C2A domain is the membrane proximal part of its cytoplasmic domain. The interaction between C2A and lipid bilayer has be en considered to be essential for triggering neurotransmitter release. In the pr esent work, the measurements of membrane surface tension and surface concentrati on showed that the C2A domain of sytⅠexhibited two membrane-bound states: the s urface adsorption state and the membrane insertion state. The surface absorption state formed in a Ca2+-independent manner with lower affinity, while the membra ne insertion state formed with high affinity was only found in the presence of C a2+. Both the Ca2+-independent and Ca2+-dependent sytⅠ- membrane interactions r equired anionic phospholipids, such as phosphatidylserine (PS). When expressed i nto rat pheochromocytoma (PC12) cells and human embryonic kidney (HEK-293) cells , as demonstrated by immunofluorescence staining and subcellular fractionation, most of the C2A was found at the plasma membrane, even when the cells were deple ted of Ca2+ by incubation with EGTA. These results suggested a new molecular mec hanism of sytⅠas a Ca2+ sensor in membrane fusion. Ca2+-independent surface ads orption might attach sytⅠto the release site during the docking or priming step . When intracellular Ca2+ increased, sytⅠtriggered the neurotransmitter release following the Ca2+-dependent penetration into the target membrane.

  16. The Zα domain of fish PKZ facilitates the B-Z conformational transition of oligonucleotide DNAs with d(GC)n inserts

    Institute of Scientific and Technical Information of China (English)

    Puzhong Lu; Shoulong Deng; Youlin Zhu; Yongbin Yan; Yong Liu; Chengyu Hu

    2012-01-01

    PKZ (PKR-like) was discovered as a member of eIF2α kinase family in fish,which possesses a conserved catalytic domain of an eIF2α kinase in C-terminal and also two ZDNA-binding domains (Zα1 and Zα2) in N-terminal.PKZ can be activated through binding of Zα to Z-DNA.However,the regulatory function of PKZ Zα still remains unclear.To investigate a molecular mechanism of how PKZ Zα interacts with Z-DNA,we expressed Zα polypeptide Zα1α2 in Escherichia coli Rosetta strain and purified by affinity chromatography on Ni-NTA resin.Different lengths of oligonucleotide DNAs with various inserts,namely d(GC)n (n =6,8,10,13),d(TA)n (n =6,10),nond(GC),and non-d(TA),were designed and synthesized.Circular dichroism spectrum and gel mobility shift assays were used to investigate the effects of Zα1α2 on the conformational transition of different oligonucleotide DNAs.Results showed that oligonucleotide DNAs retained a conventional B-DNA conformation in the absence of Zα1α2.With the increasing amount of Zα1α2 titration,d(GC)n were recognized and converted to Z-DNA conformation to some degree.With increasing the repeat number (from n =6 to n =13),the tendency of conformational transition became more obvious.However,the conformation of oligonucleotides with d(TA)n inserts changed a little in the presence of Zα1α2,and Zα1α2 had no effect on conformational transition of oligonucleotides with non-d(GC) or non-d(TA) inserts.Gel mobility shift assays further showed that Zα1α2 could bind to oligonucleotide with d(GC)10.In other words,Zα1α2 can turn oligonucleotides with d(GC)n inserts into Z-DNA conformation and bind to it with high affinity.

  17. Binding of the AVR4 elicitor of Cladosporium fulvum to chitotriose units is facilitated by positive allosteric protein-protein interactions - The chitin-binding site of AVR4 represents a novel binding site on the folding scaffold shared between the invertebrate and the plant chitin-binding domain

    NARCIS (Netherlands)

    Burg, H.A. van den; Spronk, C.A.E.M.; Boeren, S.; Kennedy, M.A.; Vissers, J.P.C.; Vuister, G.W.; Wit, P. de; Vervoort, J.

    2004-01-01

    The attack of fungal cell walls by plant chitinases is an important plant defense response to fungal infection. Anti-fungal activity of plant chitinases is largely restricted to chitinases that contain a noncatalytic, plant-specific chitin-binding domain (ChBD) ( also called Hevein domain). Current

  18. Heterologous expression of new antifungal chitinase from wheat.

    Science.gov (United States)

    Singh, Arpita; Kirubakaran, S Isaac; Sakthivel, N

    2007-11-01

    Chitinases (EC 3.2.1.14) have been grouped into seven classes (class I-VII) on the basis of their structural properties. Chitinases expressed during plant-microbe interaction are involved in defense responses of host plant against pathogens. In the present investigation, chitinase gene from wheat has been subcloned and overexpressed in Escherichia coli BL-21 (DE3). Molecular phylogeny analyses of wheat chitinase indicated that it belongs to an acidic form of class VII chitinase (glycosyl hydrolase family 19) and shows 77% identity with other wheat chitinase of class IV and low level identity to other plant chitinases. The three-dimensional structural model of wheat chitinase showed the presence of 10 alpha-helices, 3 beta-strands, 21 loop turns and the presence of 6 cysteine residues that are responsible for the formation of 3 disulphide bridges. The active site residues (Glu94 and Glu103) may be suggested for its antifungal activity. Expression of chitinase (33 kDa) was confirmed by SDS-PAGE and Western hybridization analyses. The yield of purified chitinase was 20 mg/L with chitinase activity of 1.9 U/mg. Purified chitinase exerted a broad-spectrum antifungal activity against Colletotrichum falcatum (red rot of sugarcane) Pestalotia theae (leaf spot of tea), Rhizoctonia solani (sheath blight of rice), Sarocladium oryzae (sheath rot of rice) Alternaria sp. (grain discoloration of rice) and Fusarium sp. (scab of rye). Due to its innate antifungal potential wheat chitinase can be used to enhance fungal-resistance in crop plants. PMID:17697785

  19. Role of Chitin and Chitinase/Chitinase-Like Proteins in Inflammation, Tissue Remodeling, and Injury

    Science.gov (United States)

    Lee, Chun Geun; Da Silva, Carla A.; Dela Cruz, Charles S.; Ahangari, Farida; Ma, Bing; Kang, Min-Jong; He, Chuan-Hua; Takyar, Seyedtaghi; Elias, Jack A.

    2013-01-01

    The 18 glycosyl hydrolase family of chitinases is an ancient gene family that is widely expressed from prokaryotes to eukaryotes. In mammals, despite the absence of endogenous chitin, a number of chitinases and chitinase-like proteins (C/CLPs) have been identified. However, their roles have only recently begun to be elucidated. Acidic mammalian chitinase (AMCase) inhibits chitin-induced innate inflammation; augments chitin-free, allergen-induced Th2 inflammation; and mediates effector functions of IL-13. The CLPs BRP-39/YKL-40 (also termed chitinase 3-like 1) inhibit oxidant-induced lung injury, augments adaptive Th2 immunity, regulates apoptosis, stimulates alternative macrophage activation, and contributes to fibrosis and wound healing. In accord with these findings, levels of YKL-40 in the lung and serum are increased in asthma and other inflammatory and remodeling disorders and often correlate with disease severity. Our understanding of the roles of C/CLPs in inflammation, tissue remodeling, and tissue injury in health and disease is reviewed below. PMID:21054166

  20. Cladosporium fulvum Avr4 protects fungal cell walls against hydrolysis by plant chitinases accumulating during infection.

    Science.gov (United States)

    van den Burg, Harrold A; Harrison, Stuart J; Joosten, Matthieu H A J; Vervoort, Jacques; de Wit, Pierre J G M

    2006-12-01

    Resistance against the leaf mold fungus Cladosporium fulvum is mediated by the tomato Cf proteins which belong to the class of receptor-like proteins and indirectly recognize extracellular avirulence proteins (Avrs) of the fungus. Apart from triggering disease resistance, Avrs are believed to play a role in pathogenicity or virulence of C. fulvum. Here, we report on the avirulence protein Avr4, which is a chitin-binding lectin containing an invertebrate chitin-binding domain (CBM14). This domain is found in many eukaryotes, but has not yet been described in fungal or plant genomes. We found that interaction of Avr4 with chitin is specific, because it does not interact with other cell wall polysaccharides. Avr4 binds to chitin oligomers with a minimal length of three N-acetyl glucosamine residues. In vitro, Avr4 protects chitin against hydrolysis by plant chitinases. Avr4 also binds to chitin in cell walls of the fungi Trichoderma viride and Fusarium solani f. sp. phaseoli and protects these fungi against normally deleterious concentrations of plant chitinases. In situ fluorescence studies showed that Avr4 also binds to cell walls of C. fulvum during infection of tomato, where it most likely protects the fungus against tomato chitinases, suggesting that Avr4 is a counter-defensive virulence factor.

  1. Intramolecular activation of a Ca(2+)-dependent protein kinase is disrupted by insertions in the tether that connects the calmodulin-like domain to the kinase

    Science.gov (United States)

    Vitart, V.; Christodoulou, J.; Huang, J. F.; Chazin, W. J.; Harper, J. F.; Evans, M. L. (Principal Investigator)

    2000-01-01

    Ca(2+)-dependent protein kinases (CDPK) have a calmodulin-like domain (CaM-LD) tethered to the C-terminal end of the kinase. Activation is proposed to involve intramolecular binding of the CaM-LD to a junction sequence that connects the CaM-LD to the kinase domain. Consistent with this model, a truncated CDPK (DeltaNC) in which the CaM-LD has been deleted can be activated in a bimolecular interaction with an isolated CaM-LD or calmodulin, similar to the activation of a calmodulin-dependent protein kinase (CaMK) by calmodulin. Here we provide genetic evidence that this bimolecular activation requires a nine-residue binding segment from F436 to I444 (numbers correspond to CPK-1 accession number L14771). Two mutations at either end of this core segment (F436/A and VI444/AA) severely disrupted bimolecular activation, whereas flanking mutations had only minor effects. Intramolecular activation of a full-length kinase was also disrupted by a VI444/AA mutation, but surprisingly not by a F436/A mutation (at the N-terminal end of the binding site). Interestingly, intramolecular but not bimolecular activation was disrupted by insertion mutations placed immediately downstream of I444. To show that mutant enzymes were not misfolded, latent kinase activity was stimulated through binding of an antijunction antibody. Results here support a model of intramolecular activation in which the tether (A445 to G455) that connects the CaM-LD to the kinase provides an important structural constraint and is not just a simple flexible connection.

  2. The chitinase C gene PsChiC from Pseudomonas sp. and its synergistic effects on larvicidal activity

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    Wanfang Zhong

    2015-09-01

    Full Text Available Pseudomonas sp. strain TXG6-1, a chitinolytic gram-negative bacterium, was isolated from a vegetable field in Taixing city, Jiangsu Province, China. In this study, a Pseudomonas chitinase C gene (PsChiC was isolated from the chromosomal DNA of this bacterium using a pair of specific primers. The PsChiC gene consisted of an open reading frame of 1443 nucleotides and encoded 480 amino acid residues with a calculated molecular mass of 51.66 kDa. The deduced PsChiC amino acid sequence lacked a signal sequence and consisted of a glycoside hydrolase family 18 catalytic domain responsible for chitinase activity, a fibronectin type III-like domain (FLD and a C-terminal chitin-binding domain (ChBD. The amino acid sequence of PsChiCshowed high sequence homology (> 95% with chitinase C from Serratia marcescens. SDS-PAGE showed that the molecular mass of chitinase PsChiC was 52 kDa. Chitinase assays revealed that the chitobiosidase and endochitinase activities of PsChiCwere 51.6- and 84.1-fold higher than those of pET30a, respectively. Although PsChiC showed little insecticidal activity towards Spodoptera litura larvae, an insecticidal assay indicated that PsChiC increased the insecticidal toxicity of SpltNPV by 1.78-fold at 192 h and hastened death. These results suggest that PsChiC from Pseudomonas sp. could be useful in improving the pathogenicity of baculoviruses.

  3. Molecular cloning of class III chitinase gene from Avicennia marina and its expression analysis in response to cadmium and lead stress.

    Science.gov (United States)

    Wang, Li-Ying; Wang, You-Shao; Zhang, Jing-Ping; Gu, Ji-Dong

    2015-10-01

    Mangrove species have high tolerance to heavy metal pollution. Chitinases have been widely reported as defense proteins in response to heavy metal stress in terrestrial plants. In this study, a full-length cDNA sequence encoding an acidic and basic class III chitinase (AmCHI III) was cloned by using RT-PCR and RACE methods in Avicennia marina. AmCHI III mRNA expression in leaf of A. marina were investigated under Cd, Pb stresses on using real-time quantitative PCR. The deduced AmCHI III protein consists of 302 amino acids, including a signal putative peptide region, and a catalytic domain. Homology modeling of the catalytic domain revealed a typical molecular structure of class III plant chitinases. Results further demonstrated that the regulation of AmCHI III mRNA expression in leaves was strongly dependent on Cd, Pb stresses. AmCHI III mRNA expressions were significantly increased in response to Cd, Pb, and peaked at 7 days Cd-exposure, 7 days Pb-exposure, respectively. AmCHI III mRNA expression exhibited more sensitive to Pb stress than Cd stress. This work was the first time cloing chitinase from A. marina, and it brought evidence on chitinase gene involving in heavy metals (Cd(2+) and Pb(2+)) resistance or detoxification in plants. Further studies including the promoter and upstream regulation, gene over-expression and the response of mangrove chitinases to other stresses will shed more light on the role of chitinase in mangrove plants. PMID:26044930

  4. Two chitinase-like proteins abundantly accumulated in latex of mulberry show insecticidal activity

    Directory of Open Access Journals (Sweden)

    Komatsu Aino

    2010-01-01

    Full Text Available Abstract Background Plant latex is the cytoplasm of highly specialized cells known as laticifers, and is thought to have a critical role in defense against herbivorous insects. Proteins abundantly accumulated in latex might therefore be involved in the defense system. Results We purified latex abundant protein a and b (LA-a and LA-b from mulberry (Morus sp. and analyzed their properties. LA-a and LA-b have molecular masses of approximately 50 and 46 kDa, respectively, and are abundant in the soluble fraction of latex. Western blotting analysis suggested that they share sequence similarity with each other. The sequences of LA-a and LA-b, as determined by Edman degradation, showed chitin-binding domains of plant chitinases at the N termini. These proteins showed small but significant chitinase and chitosanase activities. Lectin RCA120 indicated that, unlike common plant chitinases, LA-a and LA-b are glycosylated. LA-a and LA-b showed insecticidal activities when fed to larvae of the model insect Drosophila melanogaster. Conclusions Our results suggest that the two LA proteins have a crucial role in defense against herbivorous insects, possibly by hydrolyzing their chitin.

  5. The -271 G>A polymorphism of kinase insert domain-containing receptor gene regulates its transcription level in patients with non-small cell lung cancer

    International Nuclear Information System (INIS)

    Kinase insert domain-containing receptor (KDR) plays a critical role in the metastasis of cancer and is used as a molecular target in cancer therapy. We investigated the characteristics of the -271 G>A polymorphism of the KDR gene to gain information that may benefit the development of individualized therapies for patients with non-small cell lung cancer (NSCLC). The -271 G>A polymorphism of the KDR gene in 106 lung cancer patients and 203 healthy control individuals was analyzed by polymerase chain reaction (PCR) and DNA sequencing methods. Real-time quantitative PCR and immunohistochemical methods were used to evaluate KDR mRNA and protein expression levels, respectively, in frozen tumor specimens. The -271 G>A polymorphism was associated with the mRNA expression level of the KDR gene in tumor tissues (t = 2.178, P = 0.032, independent samples t-test). Compared with the AG/GG genotype, the AA genotype was associated with higher KDR mRNA expression in tumor tissues. We found no relationship between the genotype and the KDR protein expression level and no significant difference in the distribution of the KDR gene polymorphism genotypes between lung cancer patients and the control group (χ2 = 1.269, P = 0.264, Fisher's exact test). This study is the first to show that the -271 G>A polymorphism of the KDR gene may be a functional polymorphism related to the regulation of gene transcription. These findings may have important implications for therapies targeting KDR in patients with NSCLC

  6. Functional characterization of chitinase-3 reveals involvement of chitinases in early embryo immunity in zebrafish.

    Science.gov (United States)

    Teng, Zinan; Sun, Chen; Liu, Shousheng; Wang, Hongmiao; Zhang, Shicui

    2014-10-01

    The function and mechanism of chitinases in early embryonic development remain largely unknown. We show here that recombinant chitinase-3 (rChi3) is able to hydrolyze the artificial chitin substrate, 4-methylumbelliferyl-β-D-N,N',N″-triacetylchitotrioside, and to bind to and inhibit the growth of the fungus Candida albicans, implicating that Chi3 plays a dual function in innate immunity and chitin-bearing food digestion in zebrafish. This is further corroborated by the expression profile of Chi3 in the liver and gut, which are both immune- and digestion-relevant organs. Compared with rChi3, rChi3-CD lacking CBD still retains partial capacity to bind to C. albicans, but its enzymatic and antifungal activities are significantly reduced. By contrast, rChi3-E140N with the putative catalytic residue E140 mutated shows little affinity to chitin, and its enzymatic and antifungal activities are nearly completely lost. These suggest that both enzymatic and antifungal activities of Chi3 are dependent on the presence of CBD and E140. We also clearly demonstrate that in zebrafish, both the embryo extract and the developing embryo display antifungal activity against C. albicans, and all the findings point to chitinase-3 (Chi3) being a newly-identified factor involved in the antifungal activity. Taken together, a dual function in both innate immunity and food digestion in embryo is proposed for zebrafish Chi3. It also provides a new angle to understand the immune role of chitinases in early embryonic development of animals.

  7. The Modes of Action of ChiIII, a Chitinase from Mushroom Coprinopsis cinerea, Shift with Changes in the Length of GlcNAc Oligomers.

    Science.gov (United States)

    Niu, Xin; Liu, Cui-Cui; Xiong, Yuan-Jing; Yang, Ming-Mei; Ma, Fei; Liu, Zhong-Hua; Yuan, Sheng

    2016-09-21

    A putative class III endochitinase (ChiIII) was reported previously to be expressed dominantly in fruiting bodies of Coprinopsis cinerea, and its expression levels increased with the maturation of the fruiting bodies. This paper further reports that ChiIII is a novel chitinase with exo- and endoactivities. When the substrate was (GlcNAc)3-5, ChiIII exhibited exoactivity, releasing GlcNAc processively from the reducing end of (GlcNAc)3-5; when the substrate was (GlcNAc)6-7, the activity of ChiIII shifted to an endoacting enzyme, randomly splitting chitin oligosaccharides to various shorter oligosaccharides. This shift in the mode of action of ChiIII may be related to its stronger hydrolytic capacity to degrade chitin in fungal cell walls. The predicted structure of ChiIII shows that it lacks the α+β domain insertion; however, its substrate binding cleft seems to be deeper than that of common endochitinases but shallower and more open than that of common exochitinases, which may be related to its exo- and endohydrolytic activities. PMID:27573573

  8. Calorimeter insertion

    CERN Multimedia

    2006-01-01

    Calorimeter insertion between toroids in the ATLAS experiment detector Calorimeters are surrounding the inner detector. Calorimeters will absorb and measure the energies of the most charged and neutral particles after the collisions. The saved energy in the calorimeter is detected and converted to signals that are taken out with data taking electronics.

  9. From bacteria to human: a journey into the world of chitinases.

    Science.gov (United States)

    Adrangi, Sina; Faramarzi, Mohammad Ali

    2013-12-01

    Chitinases, the enzymes responsible for the biological degradation of chitin, are found in a wide range of organisms from bacteria to higher plants and animals. They participate in numerous physiological processes such as nutrition, parasitism, morphogenesis and immunity. Many organisms, in addition to chitinases, produce inactive chitinase-like lectins that despite lacking enzymatic activity are involved in several regulatory functions. Most known chitinases belong to families 18 and 19 of glycosyl hydrolases, however a few chitinases that belong to families 23 and 48 have also been identified in recent years. In this review, different aspects of chitinases and chi-lectins from bacteria, fungi, insects, plants and mammals are discussed. PMID:24095741

  10. Complete subsite mapping of a "loopful" GH19 chitinase from rye seeds based on its crystal structure.

    Science.gov (United States)

    Ohnuma, Takayuki; Umemoto, Naoyuki; Kondo, Kaori; Numata, Tomoyuki; Fukamizo, Tamo

    2013-08-19

    Crystallographic analysis of a mutated form of "loopful" GH19 chitinase from rye seeds a double mutant RSC-c, in which Glu67 and Trp72 are mutated to glutamine and alanine, respectively, (RSC-c-E67Q/W72A) in complex with chitin tetrasaccharide (GlcNAc)₄ revealed that the entire substrate-binding cleft was completely occupied with the sugar residues of two (GlcNAc)₄ molecules. One (GlcNAc)₄ molecule bound to subsites -4 to -1, while the other bound to subsites +1 to +4. Comparisons of the main chain conformation between liganded RSC-c-E67Q/W72A and unliganded wild type RSC-c suggested domain motion essential for catalysis. This is the first report on the complete subsite mapping of GH19 chitinase.

  11. A single base insertion in the putative transmembrane domain of the tyrosinase gene as a cause for tyrosinase-negative oculocutaneous albinism

    Energy Technology Data Exchange (ETDEWEB)

    Chintamaneni, C.D.; Kobayashi, Y.; Kwon, B.S. (Indiana Univ. School of Medicine, Indianapolis (United States)); Halaban, R. (Yale Univ. School of Medicine, New Haven, CT (United States)); Witkop, C.J. Jr. (Univ. of Minnesota, Minneapolis (United States))

    1991-06-15

    The authors have determined a molecular defect to be the likely basis for inactivity of the tyrosinase from a patient with tyrosinase-negative oculocutaneous albinism. A single base (thymine) was inserted in exon 5 of the tyrosinase gene following codon 471 in the putative transmembrane coding region. This insertion caused a shift in the reading frame of 19 amino acids at the 3{prime} end and introduced a premature termination signal that would be expected to truncate the protein by 21 amino acids at the carboxyl terminus. The albino tyrosinase was not recognized by antibodies directed to the carboxyl terminus of tyrosinase. Furthermore, as shown by gel electrophoresis of the immunoprecipitated protein, the tyrosinase was {approx} 3kDa smaller than normal. Similar immunoprecipitation data were obtained when cloned normal and mutant tyrosinases were expressed in COS-1 cells.

  12. Preparation of chitooligosaccharides from fungal waste mycelium by recombinant chitinase.

    Science.gov (United States)

    Lv, Mengyuan; Hu, Ying; Gänzle, Michael G; Lin, Jianguo; Wang, Changgao; Cai, Jun

    2016-07-22

    This study aimed to develop an enzymatic method for conversion of chitin from fungal waste mycelia to chitooligosaccharides. The recombinant chitinase LlChi18A from Lactococcus lactis was over-expressed by Escherichia coli BL21 (DE3) and purified by affinity chromatography. The enzymatic properties of the purified enzyme were studied by chitin oligosaccharides. Waste mycelium was pre-treated by alkaline. The optimal conditions for hydrolysis of fungal chitin by recombinant chitinase were determined by Schales method. HPLC/ESI-MS was used to determine the content of N-acetylglucosamine and chitooligosaccharides after hydrolysis. The level of reducing sugar released from pretreated mycelium by chitinase increased with the reaction time during 6 days. The main product in the hydrolysates was N,N'-diacetylchitobiose. After hydrolysis by chitinase for 5 d, the yield of N,N'-diacetylchitobiose from waste mycelium was around 10% with estimated purity of around 70%. Combination of chitinase and snailase remarkably increased the yield to 24% with purity of 78%. Fungal mycelium which contains chitin is a new potential source for obtaining food grade chitooligosaccharides. PMID:27153004

  13. Induction and purification of chitinase in Brassica napus L. ssp. oleifera infected with Phoma lingam

    DEFF Research Database (Denmark)

    Rasmussen, U.; Giese, H.; Dalgaard Mikkelsen, J.

    1992-01-01

    after tryptic digestion of the protein shows high sequence similarity to basic chitinases from bean, tobacco, potato, Arabidopsis, barley and rice, as well as to acidic chitinases from tobacco and petunia. A close serological relationship was found between the chitinase isoenzyme and an isoenzyme from...

  14. Insertional Mutations in Herpes Simplex Virus Type 1 gL Identify Functional Domains for Association with gH and for Membrane Fusion▿

    OpenAIRE

    Fan, Qing; Lin, Erick; Spear, Patricia G.

    2009-01-01

    Glycoprotein L (gL) is one of four glycoproteins required for the entry of herpes simplex virus (HSV) into cells and for virus-induced cell fusion. This glycoprotein oligomerizes with gH to form a membrane-bound heterodimer but can be secreted when expressed without gH. Twelve unique gL linker-insertion mutants were generated to identify regions critical for gH binding and gH/gL processing and regions essential for cell fusion and viral entry. All gL mutants were detected on the cell surface ...

  15. Cloning, expression and biocharacterization of OfCht5, the chitinase from the insect Ostrinia furnacalis

    Institute of Scientific and Technical Information of China (English)

    Qingyue Wu; Tian Liu; Qing Yang

    2013-01-01

    Chitinase catalyzes β-l,4-glycosidic linkages in chitin and has attracted research interest due to it being a potential pesticide target and an enzymatic tool for preparation of N-acetyl-β-D-glucosamine.An individual insect contains multiple genes encoding chitinases,which vary in domain architectures,expression patterns,physiological roles and biochemical properties.Herein,OfCht5,the glycoside hydrolase family 18 chitinase from the widespread lepidopteran pest Ostrinia furnacalis,was cloned,expressed in the yeast Pichia pastoris and biochemically characterized in an attempt to facilitate both pest control and biomaterial preparation.Complementary DNA sequence analysis indicated that OfCHT5 consisted of an open reading frame of 1 665-bp nucleotides.Phylogenic analysis suggested OfCht5 belongs to the Group Ⅰ insect chitinases.Expression of OfCht5 in Pichia pastoris resulted in highest specific activity after 120 h of induction with methanol.Through two steps of purification,consisting of ammonium sulfate precipitation and metal chelating chromatography,about 7 mg of the recombinant OfCht5 was purified to homogeneity from 1 L culture supematant.OfCht5 effectively converted colloidal chitin into chitobiose,but had relatively low activity toward α-chitin.When chitooligosaccharides [(GlcNAc)n,n =3-6] were used as substrates,OfCht5 was observed to possess the highest catalytic efficiency parameter toward (GlcNAc)4 and predominantely hydrolyzed the second glycosidic bond from the non-reducing end.Together with β-N-acetyl-D-hexosaminidase OfHexl,OfCht5 achieved its highest efficiency in chitin degradation that yielded N-acetyl-β-D-glucosamine,a valuable pharmacological reagent and food supplement,within a molar concentration ratio of OfCht5 versus OfHexl in the range of 9∶1-15 ∶ 1.This work provides an alternative to existing preparation ofchitinase for pesticides and other applications.

  16. Molecular phylogeny of C1 inhibitor depicts two immunoglobulin-like domains fusion in fishes and ray-finned fishes specific intron insertion after separation from zebrafish

    International Nuclear Information System (INIS)

    Highlights: • C1 inhibitors of fishes have two Ig domains fused in the N-terminal end. • Spliceosomal introns gain in two Ig domains of selected ray-finned fishes. • C1 inhibitors gene is maintained from 450 MY on the same locus. • C1 inhibitors gene is missing in frog and lampreys. • C1 inhibitors of tetrapod and fishes differ in the RCL region. - Abstract: C1 inhibitor (C1IN) is a multi-facet serine protease inhibitor in the plasma cascades, inhibiting several proteases, notably, regulates both complement and contact system activation. Despite huge advancements in the understanding of C1IN based on biochemical properties and its roles in the plasma cascades, the phylogenetic history of C1IN remains uncharacterized. To date, there is no comprehensive study illustrating the phylogenetic history of C1IN. Herein, we explored phylogenetic history of C1IN gene in vertebrates. Fishes have C1IN with two immunoglobulin like domains attached in the N-terminal region. The RCL regions of CIIN from fishes and tetrapod genomes have variations at the positions P2 and P1′. Gene structures of C1IN gene from selected ray-finned fishes varied in the Ig domain region with creation of novel intron splitting exon Im2 into Im2a and Im2b. This intron is limited to ray-finned fishes with genome size reduced below 1 Gb. Hence, we suggest that genome compaction and associated double-strand break repairs are behind this intron gain. This study reveals the evolutionary history of C1IN and confirmed that this gene remains the same locus for ∼450 MY in 52 vertebrates analysed, but it is not found in frogs and lampreys

  17. Molecular phylogeny of C1 inhibitor depicts two immunoglobulin-like domains fusion in fishes and ray-finned fishes specific intron insertion after separation from zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Abhishek, E-mail: akumar@bot.uni-kiel.de [Department of Genetics and Molecular Biology in Botany, Institute of Botany, Christian-Albrechts-University at Kiel, Kiel (Germany); Bhandari, Anita [Molecular Physiology, Zoological Institute, Christian-Albrechts-University at Kiel, Kiel (Germany); Sarde, Sandeep J. [Department of Genetics and Molecular Biology in Botany, Institute of Botany, Christian-Albrechts-University at Kiel, Kiel (Germany); Goswami, Chandan [National Institute of Science Education and Research, Bhubaneswar, Orissa (India)

    2014-07-18

    Highlights: • C1 inhibitors of fishes have two Ig domains fused in the N-terminal end. • Spliceosomal introns gain in two Ig domains of selected ray-finned fishes. • C1 inhibitors gene is maintained from 450 MY on the same locus. • C1 inhibitors gene is missing in frog and lampreys. • C1 inhibitors of tetrapod and fishes differ in the RCL region. - Abstract: C1 inhibitor (C1IN) is a multi-facet serine protease inhibitor in the plasma cascades, inhibiting several proteases, notably, regulates both complement and contact system activation. Despite huge advancements in the understanding of C1IN based on biochemical properties and its roles in the plasma cascades, the phylogenetic history of C1IN remains uncharacterized. To date, there is no comprehensive study illustrating the phylogenetic history of C1IN. Herein, we explored phylogenetic history of C1IN gene in vertebrates. Fishes have C1IN with two immunoglobulin like domains attached in the N-terminal region. The RCL regions of CIIN from fishes and tetrapod genomes have variations at the positions P2 and P1′. Gene structures of C1IN gene from selected ray-finned fishes varied in the Ig domain region with creation of novel intron splitting exon Im2 into Im2a and Im2b. This intron is limited to ray-finned fishes with genome size reduced below 1 Gb. Hence, we suggest that genome compaction and associated double-strand break repairs are behind this intron gain. This study reveals the evolutionary history of C1IN and confirmed that this gene remains the same locus for ∼450 MY in 52 vertebrates analysed, but it is not found in frogs and lampreys.

  18. Acidic Chitinase Limits Allergic Inflammation and Promotes Intestinal Nematode Expulsion

    Science.gov (United States)

    Acidic mammalian chitinase (AMCase) is stereotypically induced during mammalian immune responses to helminths and allergens—yet, its precise role in immunity and inflammation is unclear. Here we show that in the lung, genetic ablation of AMCase failed to diminish type 2 inflammation against helmint...

  19. Nitrogen regulates chitinase gene expression in a marine bacterium

    DEFF Research Database (Denmark)

    Delpin, Marina; Goodman, A.E.

    2009-01-01

    Ammonium concentration and nitrogen source regulate promoter activity and use for the transcription of chiA, the major chitinase gene of Pseudoalteromonas sp. S91 and S91CX, an S91 transposon lacZ fusion mutant. The activity of chiA was quantified by beta-galactosidase assay of S91CX cultures con...

  20. Chitinases Are Essential for Cell Separation in Ustilago maydis.

    Science.gov (United States)

    Langner, Thorsten; Öztürk, Merve; Hartmann, Sarah; Cord-Landwehr, Stefan; Moerschbacher, Bruno; Walton, Jonathan D; Göhre, Vera

    2015-09-01

    Chitin is an essential component of the fungal cell wall, providing rigidity and stability. Its degradation is mediated by chitinases and supposedly ensures the dynamic plasticity of the cell wall during growth and morphogenesis. Hence, chitinases should be particularly important for fungi with dramatic morphological changes, such as Ustilago maydis. This smut fungus switches from yeast to filamentous growth for plant infection, proliferates as a mycelium in planta, and forms teliospores for spreading. Here, we investigate the contribution of its four chitinolytic enzymes to the different morphological changes during the complete life cycle in a comprehensive study of deletion strains combined with biochemical and cell biological approaches. Interestingly, two chitinases act redundantly in cell separation during yeast growth. They mediate the degradation of remnant chitin in the fragmentation zone between mother and daughter cell. In contrast, even the complete lack of chitinolytic activity does not affect formation of the infectious filament, infection, biotrophic growth, or teliospore germination. Thus, unexpectedly we can exclude a major role for chitinolytic enzymes in morphogenesis or pathogenicity of U. maydis. Nevertheless, redundant activity of even two chitinases is essential for cell separation during saprophytic growth, possibly to improve nutrient access or spreading of yeast cells by wind or rain.

  1. Identification of glutamic acid 204 and aspartic acid 200 in chitinase A1 of Bacillus circulans WL-12 as essential residues for chitinase activity.

    Science.gov (United States)

    Watanabe, T; Kobori, K; Miyashita, K; Fujii, T; Sakai, H; Uchida, M; Tanaka, H

    1993-09-01

    Prokaryotic chitinases, class III plant chitinases, yeast chitinases, and endo-beta-N-acetylglucosaminidases share weak amino acid sequence similarities at the certain region of each enzyme. These regions have been assumed to be important for catalytic activities of the enzymes. To verify this assumption, three amino acid residues (Ser-160, Asp-200, Glu-204) in chitinase A1 of Bacillus circulans WL-12 were chosen, based on the amino acid sequence alignment of the regions sharing sequence similarity, and were replaced by site-directed mutagenesis. Kinetic parameters for 4-methylumbelliferyl-N,N',N"-triacetylchitotriose hydrolysis were determined with wild-type and seven mutant chitinases. Chitinases with Glu-204-->Gln mutation and Glu-204-->Asp mutation were essentially inactive and kcat values of these chitinases were approximately 1/5,000 and 1/17,000 of that of wild-type chitinase, respectively. Asp-200-->Asn mutation decreased the kcat value to approximately 1/350 of that of the wild-type enzyme, while the Km value decreased only slightly. On the other hand, neither the kcat value nor the Km value was affected by Asp-200-->Glu mutation. Thus, it appeared that Glu-204 and Asp-200 are directly involved in the catalytic events of chitinase A1. The role of the carboxyl group of Asp-200 can be fully substituted by that of Glu residue. The Ser-160-->Ala mutant retained 10% activity of the wild-type chitinase indicating that the hydroxyl group of Ser-160 is not absolutely required for the catalytic activity. These results indicate a lysozyme-type catalytic mechanism of the chitinase.

  2. IN SILICO ANALYSIS OF CHITINASE PROMOTER ISOLATED FROM DROSERA ROTUNDIFOLIA L.

    OpenAIRE

    Dominika Ďurechová; Ildikó Matušíková; Jana Moravčíková; Martin Jopčík; Jana Libantová

    2014-01-01

    Chitinases occur in dozens of genes in the individual plant species and play diverse roles in plant growth and development, and during the plant defense to biotic and abiotic stress. Here we focused on isolation and in silico characterization of regulatory sequences of chitinase gene that belongs to the first isolated gene sequences from D. rotundifolia overall. For the isolation of the 739 bp sequence of chitinase promoter the genome walking approach was applied. The authenticity of the obta...

  3. Reduced Chitinase Activities in Ant Plants of the Genus Macaranga

    Science.gov (United States)

    Heil, Martin; Fiala, Brigitte; Linsenmair, K. Eduard; Boller, Thomas

    Many plant species have evolved mutualistic associations with ants, protecting their host against detrimental influences such as herbivorous insects. Letourneau (1998) reported in the case of Piper that ants defend their plants principally against stem-boring insects and also reduce fungal infections on inflorescences. Macaranga plants that were experimentally deprived of their symbiotic Crematogaster ants suffered heavily from shoot borers and pathogenic fungi (Heil 1998). Here we report that ants seem to reduce fungal infections actively in the obligate myrmecophyte Macarangatriloba (Euphorbiaceae), while ant-free plants can be easily infected. We also found extremely low chitinase activity in Macaranga plants. The plants' own biochemical defense seems to be reduced, and low chitinase activity perhaps may represent a predisposition for the evolution of myrmecophytism. These plants are therefore highly dependent on their ants, which obviously function not only as an antiherbivore defense but also as an effective agent against fungal pathogens.

  4. Isolation of bacteria producing chitinase and inhibiting growth of Rhizoctonia solani

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Five bacteria strains with higher chitinase activity were isolated by using a technique of enriched cell wall of R. solani. All of them showed inhibiting effect on the growth of R. solani. Being cultured 3 d, strain CH-1 showed higher chitinase activity on the chitin plate. The diameter of the transparent circle reached 8.7 mm (4 replications) . In the antagonistic test to R. solani in PDA plate, the circle was 18.1 mm. It was also observed that the antagonistic ability of some strains was not consistent with the chitinase activity (Table 1). It may be connected with the secretion of chitinase at different culture situations.

  5. Molecular and functional evolution of class I chitinases for plant carnivory in the caryophyllales.

    Science.gov (United States)

    Renner, Tanya; Specht, Chelsea D

    2012-10-01

    Proteins produced by the large and diverse chitinase gene family are involved in the hydrolyzation of glycosidic bonds in chitin, a polymer of N-acetylglucosamines. In flowering plants, class I chitinases are important pathogenesis-related proteins, functioning in the determent of herbivory and pathogen attack by acting on insect exoskeletons and fungal cell walls. Within the carnivorous plants, two subclasses of class I chitinases have been identified to play a role in the digestion of prey. Members of these two subclasses, depending on the presence or absence of a C-terminal extension, can be secreted from specialized digestive glands found within the morphologically diverse traps that develop from carnivorous plant leaves. The degree of homology among carnivorous plant class I chitinases and the method by which these enzymes have been adapted for the carnivorous habit has yet to be elucidated. This study focuses on understanding the evolution of carnivory and chitinase genes in one of the major groups of plants that has evolved the carnivorous habit: the Caryophyllales. We recover novel class I chitinase homologs from species of genera Ancistrocladus, Dionaea, Drosera, Nepenthes, and Triphyophyllum, while also confirming the presence of two subclasses of class I chitinases based upon sequence homology and phylogenetic affinity to class I chitinases available from sequenced angiosperm genomes. We further detect residues under positive selection and reveal substitutions specific to carnivorous plant class I chitinases. These substitutions may confer functional differences as indicated by protein structure homology modeling. PMID:22490823

  6. Purification and characterization of chitinase from Streptomyces violascens NRRL B2700.

    Science.gov (United States)

    Gangwar, Mamta; Singh, Vineeta; Pandey, Asheesh Kumar; Tripathi, C K M; Mishra, B N

    2016-01-01

    Chitinase is one of the important enzymes as it is directly linked to Chitin that has wide applications in industrial, medical and commercial fields for its biocompatibility and biodegradability. Here, we report extracellular chitinase production by Streptomyces violascens NRRL B2700 under submerged fermentation condition. Chitinase production started after 10 h of incubation and reached to maximum level at 72 h of cultivation. Studies on the influence of additional carbon and nitrogen sources on chitinase production revealed that maltose, xylose, fructose, lactose, soybean meal and ammonium nitrate served as good carbon and nitrogen sources to enhance chitinase yield by 1.6 to 6 fold. Medium supplemented with 1% colloidal chitin produced high chitinase concentration (0.1714 U/mg). The enzyme chitinase was purified from the culture broth by 75% ammonium sulphate precipitation, DEAE-cellulose ion-exchange and sephadex G-100 gel filtration. The molecular mass of the purified chitinase was 65 kDa as estimated by SDS-PAGE. The apparent Michaelis constant (K(m)) and the maximum rate (V(max)) of the enzyme for colloidal chitin were 1.556 mg/mL and 2.680 μM/min/mg, respectively suggested high affinity towards-chitin. Possibly, it is the first report on production of chitinase from S. violascens NRRL B2700. The findings were encouraging, especially for cost effective production, and further warrants media and purification optimization studies for enhanced yield. PMID:26891554

  7. EXPRESSION OF CHITINASE GENE IN TRANSGENIC RAPE PLANTS

    OpenAIRE

    Lu Longdou; Gao Wu Jun; Wang Jingxue; Duan Hongying; Li Ruili

    2005-01-01

    The hypocotyl and cotyledon of Brassica napus L. H165 and Brassica juncea DB3 were transformed with chitinase gene and herbicide-resistance gene by co-culture with Agrobacterium tumefacients LBA4404, and rape plants were obtained which could grow on the medium containing herbicide. The PCR result showed that exotic genes were integrated in the genome of the rape. Further study was performed to determine the impact of temperature on the transgenic rate and the differentiation o...

  8. ZYMOGRAPHIC IDENTIFICATION AND BIOCHEMICAL CHARACTERIZATION OF CHITINASE AGAINST PHYTOFUNGAL PATHOGENS

    Directory of Open Access Journals (Sweden)

    Urja Pandya

    2014-08-01

    Full Text Available An endospore forming Gram positive bacterium (MBCU4 was isolated from a vermicompost amended soil, and confirmed as Bacillus subtilis through the 16S rRNA sequence analysis. An extracellular chitinase was detected from this strain of B. subtilis under specific environmental condition. An attempt was made to purify the enzyme by ammonium sulfate precipitation followed by DEAE sepharose CL-6B column chromatography. The purified enzyme was demonstrated as a single band, having the molecular weight 31kDa on SDS PAGE analysis and its activity in the gel was determined by clear zone on zymogram. Further characterization of the isolated enzymes has showed that this enzyme is most active at pH 6.0 and at the optimized temperature of 50 0C. The purified chitinase exhibited high degree of antifungal activity particularly by degrading their cell wall components of plant pathogens Macrophomina phaseolina (69.0% and Rhizoctonia solani (52.0%. It infers that the chitinase produced by B. subtilis could play an important role for biopesticidal activity.

  9. Entamoeba histolytica Lectins Contain Unique 6-Cys or 8-Cys Chitin-Binding Domains

    OpenAIRE

    Van Dellen, Katrina; Ghosh, Sudip K.; Robbins, Phillips W.; Loftus, Brendan; Samuelson, John

    2002-01-01

    The Jacob lectin, the most abundant glycoprotein in the cyst wall of Entamoeba invadens, contains five unique 6-Cys chitin-binding domains (CBDs). We identified Entamoeba histolytica and Entamoeba dispar genes encoding Jacob homologues, each of which contains two predicted 6-Cys CBDs. A unique 8-Cys CBD was found at the N termini of the E. histolytica chitinase and three other predicted lectins, called Jessie 1 to Jessie 3. The CBDs of four E. histolytica lectins (Jacob, chitinase, and Jessie...

  10. Polymorphisms and Haplotypes of Acid Mammalian Chitinase Are Associated with Bronchial Asthma

    OpenAIRE

    Bierbaum, Sibylle; Nickel, Renate; Koch, Anja; Lau, Susanne; Deichmann, Klaus A.; Wahn, Ulrich; Superti-Furga, Andrea; Heinzmann, Andrea

    2005-01-01

    Rationale: Chitinases are enzymes that cleave chitin, a polysaccharide contained in many parasites of humans. Recent studies in mouse models of bronchial asthma have shown that acid mammalian chitinase (AMCase) is involved in the pathophysiology of asthma. It acts downstream of interleukin-13; inhibition of AMCase leads to an abrogated T-helper cell 2 inflammation, less bronchial hyperreactivity, and fewer eosinophils.

  11. Antimicrobial peptide inhibition of fungalysin proteases that target plant type 19 Family IV defense chitinases

    Science.gov (United States)

    Cereal crops and other plants produce secreted seed chitinases that reduce pathogenic infection, most likely by targeting the fungal chitinous cell wall. We have shown that corn (Zea mays) produces three GH family 19, plant class IV chitinases, that help in protecting the plant against Fusarium and ...

  12. Cloning and characterization of a pathogen-induced chitinase in Brassica napus

    DEFF Research Database (Denmark)

    Rasmussen, U.; Bojsen, K.; Collinge, D.B.

    1992-01-01

    A chitinase cDNA clone from rapeseed (Brassica napus L. ssp. oleifera) was isolated. The cDNA clone, ChB4, represents a previously purified and characterized basic chitinase isozyme. The longest open reading frame in ChB4 encodes a polypeptide of 268 amino acids. This polypeptide consists of a 24...

  13. Low chitinase activity in Acacia myrmecophytes: a potential trade-off between biotic and chemical defences?

    Science.gov (United States)

    Heil, M.; Staehelin, Christian; McKey, D.

    We determined chitinase activity in leaves of four myrmecophytic and four non-myrmecophytic leguminous species at the plants' natural growing sites in Mexico. Myrmecophytic plants (or 'ant plants') have obligate mutualisms with ants protecting them against herbivores and pathogenic fungi. Plant chitinases can be considered a reliable measure of plant resistance to pathogenic fungi. The myrmecophytic Acacia species, which were colonised by mutualistic ants, exhibited at least six-fold lower levels of chitinase activity compared with the non-myrmecophytic Acacia farnesiana and three other non-myrmecophytes. Though belonging to different phylogenetic groups, the myrmecophytic Acacia species formed one distinct group in the data set, which was clearly separated from the non-myrmecophytic species. These findings allowed for comparison between two recent hypotheses that attempt to explain low chitinase activity in ant plants. Most probably, chitinases are reduced in myrmecophytic plant species because these are effectively defended indirectly due to their symbiosis with mutualistic ants.

  14. Cloning and overexpression of antifungal barley chitinase gene in Escherichia coli.

    Science.gov (United States)

    Kirubakaran, S Isaac; Sakthivel, N

    2007-03-01

    Plant chitinases are pathogenesis-related proteins, which are believed to be involved in plant defense responses to pathogen infection. In this study, chitinase gene from barley was cloned and overexpressed in Escherichia coli. Chitinase (35 kDa) was isolated and purified. Since the protein was produced as insoluble inclusion bodies, the protein was solubilized and refolded. Purified chitinase exerted broad-spectrum antifungal activity against Botrytis cinerea (blight of tobacco), Pestalotia theae (leaf spot of tea), Bipolaris oryzae (brown spot of rice), Alternaria sp. (grain discoloration of rice), Curvularia lunata (leaf spot of clover) and Rhizoctonia solani (sheath blight of rice). Due to the potential of broad-spectrum antifungal activity barley chitinase gene can be used to enhance fungal-resistance in crop plants such as rice, tobacco, tea and clover. PMID:17029984

  15. Chitinases from the Plant Disease Biocontrol Agent, Stenotrophomonas maltophilia C3.

    Science.gov (United States)

    Zhang, Z; Yuen, G Y; Sarath, G; Penheiter, A R

    2001-02-01

    ABSTRACT Stenotrophomonas maltophilia strain C3, a biocontrol agent of Bipolaris sorokiniana in turfgrass, produced chitinases in broth media containing chitin. Chitinases were partially purified from culture fluid by ammonium sulfate precipitation and chitin affinity chromatography. The chromatography fraction with the highest specific chitinase activity was inhibitory to conidial germination and germ-tube elongation of B. sorokiniana, but it was less inhibitory than the protein fraction or the raw culture filtrate. The fraction exhibited strong exochitinase and weak endo-chitinase activity. Optimum temperature and pH for chitinase activity were 45 to 50 degrees C and 4.5 to 5.0, respectively. Chitinase activity was inhibited by Hg(2+) and Fe(3+), but not by other metal ions or enzyme inhibitors. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the chromatography fraction revealed the presence of five protein bands of 25, 32, 48, 65, and 75 kDa. Partial amino acid sequences of the 32-, 65-, and 75-kDa proteins indicated that they are homologous to known bacterial chitinases. There was no homology found in the partial amino acid sequences of the 25- and 48-kDa proteins to any known chitinases. Five chitinase-active proteins were detected in the protein and chromatography fractions by activity gels, but when each protein was extracted and re-electrophoresed separately under denaturing conditions, only 32- or 48-kDa proteins were revealed. It was concluded that strain C3 produces at least two chitinases that are antifungal.

  16. EXPRESSION OF CHITINASE GENE IN TRANSGENIC RAPE PLANTS

    Directory of Open Access Journals (Sweden)

    Lu Longdou

    2005-08-01

    Full Text Available The hypocotyl and cotyledon of Brassica napus L. H165 and Brassica juncea DB3 were transformed with chitinase gene and herbicide-resistance gene by co-culture with Agrobacterium tumefacients LBA4404, and rape plants were obtained which could grow on the medium containing herbicide. The PCR result showed that exotic genes were integrated in the genome of the rape. Further study was performed to determine the impact of temperature on the transgenic rate and the differentiation of explants.

  17. Measuring Chitinase and Protease Activity in Cultures of Fungal Entomopathogens.

    Science.gov (United States)

    Cheong, Peter; Glare, Travis R; Rostás, Michael; Haines, Stephen R

    2016-01-01

    Entomopathogenic fungi produce a variety of destructive enzymes and metabolites to overcome the unique defense mechanisms of insects. In a first step, fungal chitinases and proteinases need to break down the insect's cuticle. Both enzyme classes support the infection process by weakening the chitin barrier and by producing nutritional cleavage products for the fungus. In a second step, the pathogen can now mechanically penetrate the weakened cuticle and reach the insect's hemolymph where it starts proliferating. The critical enzymes chitinase and proteinase are also excreted into the supernatants of fungal cultures and can be used as indicators of virulence. Chromogenic assays adapted for 96-well microtiter plates that measure these enzymes provide a sensitive, fast, and easy screening method for evaluating the potential biocontrol activity of fungal isolates and may be considered as an alternative to laborious and time-consuming bioassays. Furthermore, monitoring fungal enzyme production in dependence of time, nutrient sources, or other factors can facilitate in establishing optimal growth and harvesting conditions for selected isolates with the aim of achieving maximum biocontrol activity. PMID:27565500

  18. Chitinase genes revealed and compared in bacterial isolates, DNA extracts and a metagenomic library from a phytopathogen suppressive soil

    Energy Technology Data Exchange (ETDEWEB)

    Hjort, K.; Bergstrom, M.; Adesina, M.F.; Jansson, J.K.; Smalla, K.; Sjoling, S.

    2009-09-01

    Soil that is suppressive to disease caused by fungal pathogens is an interesting source to target for novel chitinases that might be contributing towards disease suppression. In this study we screened for chitinase genes, in a phytopathogen-suppressive soil in three ways: (1) from a metagenomic library constructed from microbial cells extracted from soil, (2) from directly extracted DNA and (3) from bacterial isolates with antifungal and chitinase activities. Terminal-restriction fragment length polymorphism (T-RFLP) of chitinase genes revealed differences in amplified chitinase genes from the metagenomic library and the directly extracted DNA, but approximately 40% of the identified chitinase terminal-restriction fragments (TRFs) were found in both sources. All of the chitinase TRFs from the isolates were matched to TRFs in the directly extracted DNA and the metagenomic library. The most abundant chitinase TRF in the soil DNA and the metagenomic library corresponded to the TRF{sup 103} of the isolate, Streptomyces mutomycini and/or Streptomyces clavifer. There were good matches between T-RFLP profiles of chitinase gene fragments obtained from different sources of DNA. However, there were also differences in both the chitinase and the 16S rRNA gene T-RFLP patterns depending on the source of DNA, emphasizing the lack of complete coverage of the gene diversity by any of the approaches used.

  19. Production of chitinases with Trichoderma harzianun isolates using solid substrate fermentation

    Institute of Scientific and Technical Information of China (English)

    Viviana Nagy

    2004-01-01

    @@ Over forty Trichoderma harzianum isolates have been screened in solid substrate fermentation (SSF)for chitinase production. Strains were isolated from Asian soil and tree bark samples. Identification was performed in Canada and Austria by classical and molecular taxonomical methods.

  20. Antifungal chitinase against human pathogenic yeasts from Coprinellus congregatus.

    Science.gov (United States)

    Yoo, Yeeun; Choi, Hyoung T

    2014-05-01

    The inky cap, Coprinellus congregatus, produces mushrooms which become autolyzed rapidly to generate black liquid droplets, in which no cell wall is detected by microscopy. A chitinase (Chi2) which is synthesized during the autolytic phase of C. congregatus inhibits the growths of Candida albicans and Cryptococcus neoformans up to 10% at the concentration of 10 μg/ml, about 50% at concentration of 20 μg/ml, and up to 95% at the concentration of 70 μg/ml. Upon treatment these yeast cells are observed to be severely deformed, with the formation of large holes in the cell wall. The two yeast species show no growth inhibition at the concentration of 5 μg/ml, which means the minimum inhibitory concentrations for both yeast species are 10 μg/ml under these experimental conditions. PMID:24535739

  1. Dual protonophore-chitinase inhibitors dramatically affect O. volvulus molting.

    Science.gov (United States)

    Gooyit, Major; Tricoche, Nancy; Lustigman, Sara; Janda, Kim D

    2014-07-10

    The L3-stage-specific chitinase OvCHT1 has been implicated in the development of Onchocerca volvulus, the causative agent of onchocerciasis. Closantel, a known anthelmintic drug, was previously discovered as a potent and specific OvCHT1 inhibitor. As closantel is also a known protonophore, we performed a simple scaffold modulation to map out the structural features that are relevant for its individual or dual biochemical roles. Furthermore, we present that either OvCHT1 inhibition or protonophoric activity was capable of affecting O. volvulus L3 molting and that the presence of both activities in a single molecule yielded more potent inhibition of the nematode's developmental process. PMID:24918716

  2. Aromatic-Mediated Carbohydrate Recognition in Processive Serratia marcescens Chitinases.

    Science.gov (United States)

    Jana, Suvamay; Hamre, Anne Grethe; Wildberger, Patricia; Holen, Matilde Mengkrog; Eijsink, Vincent G H; Beckham, Gregg T; Sørlie, Morten; Payne, Christina M

    2016-02-25

    Microorganisms use a host of enzymes, including processive glycoside hydrolases, to deconstruct recalcitrant polysaccharides to sugars. Processive glycoside hydrolases closely associate with polymer chains and repeatedly cleave glycosidic linkages without dissociating from the crystalline surface after each hydrolytic step; they are typically the most abundant enzymes in both natural secretomes and industrial cocktails by virtue of their significant hydrolytic potential. The ubiquity of aromatic residues lining the enzyme catalytic tunnels and clefts is a notable feature of processive glycoside hydrolases. We hypothesized that these aromatic residues have uniquely defined roles, such as substrate chain acquisition and binding in the catalytic tunnel, that are defined by their local environment and position relative to the substrate and the catalytic center. Here, we investigated this hypothesis with variants of Serratia marcescens family 18 processive chitinases ChiA and ChiB. We applied molecular simulation and free energy calculations to assess active site dynamics and ligand binding free energies. Isothermal titration calorimetry provided further insight into enthalpic and entropic contributions to ligand binding free energy. Thus, the roles of six aromatic residues, Trp-167, Trp-275, and Phe-396 in ChiA, and Trp-97, Trp-220, and Phe-190 in ChiB, have been examined. We observed that point mutation of the tryptophan residues to alanine results in unfavorable changes in the free energy of binding relative to wild-type. The most drastic effects were observed for residues positioned at the "entrances" of the deep substrate-binding clefts and known to be important for processivity. Interestingly, phenylalanine mutations in ChiA and ChiB had little to no effect on chito-oligomer binding, in accordance with the limited effects of their removal on chitinase functionality. PMID:26824449

  3. ISOLATION AND CHARACTERIZATION OF CHITINASE GENE FROM THE UNTRADITIONAL PLANT SPECIES

    OpenAIRE

    Dominika Ďurechová; Ildikó Matušíková; Jana Moravčíková; Martin Jopčík; Jana Libantová

    2013-01-01

    Round-leaf sundew (Drosera rotundifolia L.) from Droseraceae family belongs among a few plant species with strong antifungal potential. It was previously shown that chitinases of carnivorous plant species may play role during the insect prey digestion, when hard chitin skeleton is being decomposed. As many phytopathogenic fungi contain chitin in their cell wall our attention in this work was focused on isolation and in silico characterization of genomic DNA sequence of sundew chitinase gene. ...

  4. Chitinase expression in Listeria monocytogenes is positively regulated by the Agr system

    DEFF Research Database (Denmark)

    Paspaliari, Dafni Katerina; Mollerup, Maria Storm; Kallipolitis, Birgitte H.;

    2014-01-01

    The food-borne pathogen Listeria monocytogenes encodes two chitinases, ChiA and ChiB, which allow the bacterium to hydrolyze chitin, the second most abundant polysaccharide in nature. Intriguingly, despite the absence of chitin in human and mammalian hosts, both of the chitinases have been deemed....... Our results highlight a previously unrecognized role of the agr system and suggest that autoinducer-based regulation of chitinolytic systems may be more commonplace than previously thought....

  5. Fungal chitinases: function, regulation, and potential roles in plant/pathogen interactions.

    Science.gov (United States)

    Langner, Thorsten; Göhre, Vera

    2016-05-01

    In the past decades our knowledge about fungal cell wall architecture increased tremendously and led to the identification of many enzymes involved in polysaccharide synthesis and remodeling, which are also of biotechnological interest. Fungal cell walls play an important role in conferring mechanic stability during cell division and polar growth. Additionally, in phytopathogenic fungi the cell wall is the first structure that gets into intimate contact with the host plant. A major constituent of fungal cell walls is chitin, a homopolymer of N-acetylglucosamine units. To ensure plasticity, polymeric chitin needs continuous remodeling which is maintained by chitinolytic enzymes, including lytic polysaccharide monooxygenases N-acetylglucosaminidases, and chitinases. Depending on the species and lifestyle of fungi, there is great variation in the number of encoded chitinases and their function. Chitinases can have housekeeping function in plasticizing the cell wall or can act more specifically during cell separation, nutritional chitin acquisition, or competitive interaction with other fungi. Although chitinase research made huge progress in the last decades, our knowledge about their role in phytopathogenic fungi is still scarce. Recent findings in the dimorphic basidiomycete Ustilago maydis show that chitinases play different physiological functions throughout the life cycle and raise questions about their role during plant-fungus interactions. In this work we summarize these functions, mechanisms of chitinase regulation and their putative role during pathogen/host interactions. PMID:26527115

  6. Cloning and expression analysis of the chitinase gene Ifu-chit2 from Isaria fumosorosea

    Directory of Open Access Journals (Sweden)

    Huimin Meng

    2015-09-01

    Full Text Available Entomopathogenic fungi can produce a series of chitinases, some of which function synergistically with proteases and other hydrolytic enzymes to degrade the insect cuticle. In the present study, the chitinase gene Ifu-chit2 from Isaria fumosorosea was investigated. The Ifu-chit2 gene is 1,435-bp long, interrupted by three short introns, and encodes a predicted protein of 423 amino acids with a 22 residue signal peptide. The predicted Ifu-Chit2 protein is highly homologous to Beauveria bassiana chitinase Bbchit2 and belongs to the glycohydrolase family 18. Ifu-Chit2 was expressed in Escherichia coli to verify chitinase activity, and the recombinant enzyme exhibited activity with a colloidal chitin substrate. Furthermore, the expression profiles of Ifu-chit2 were analyzed at different induction times under in vivo conditions. Quantitative real-time PCR analysis revealed that Ifu-chit2 expression peaked at two days post-induction. The expression of chitinase Ifu-chit2 in vivo suggests that the chitinase may play a role in the early stage of pathogenesis.

  7. Effect of Cultural Conditions on Chitinase Production from Biocontrol Bacterium Against Aflatoxin

    Institute of Scientific and Technical Information of China (English)

    Kai Wang; Peisheng Yan; and Lixin Cao

    2015-01-01

    Chitinase is one of the most important mycolytic enzymes with industrial significance. Statistical methods are employed to optimize cultural conditions with the increased production of chitinase for the selected Serratia marcescens JPP1, which are obtained from peanut hulls in Jiangsu Province, China and exhibit antagonistic activity against aflatoxins. Using single⁃factor experiments the effects of cultural conditions ( broth content, inoculum size and rotation speed) on chitinase production from S. marcescens JPP1 are evaluated. Central composite design of Response Surface Methodology is used to optimize the levels of factors for the best yield of enzymes production. The optimized cultural conditions for obtaining the highest level of chitinase production are 23�2 mL broth content, 116 r/min rotation speed and 4�3% inoculum size. A quadratic regression model of chitinase production is built ( R2 = 0�970 9) and the verification experiments confirm its validity. The maximum chitinase production obtained after the optimization is 29�58 U/mL for a 1�4⁃fold increase.

  8. Purification, characterization and antimicrobial activity of chitinase from marine-derived Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    Aida M. Farag

    2016-06-01

    Full Text Available Chitinase (EC 3.2.1.14 was produced from the culture filtrate of marine-derived Aspergillus terreus and purified by 65% ammonium sulphate precipitation, followed by gel filtration on Sephadex G-100 and DEAE-Sephadex A-50 ion exchange chromatography, with 5.16-fold of purification and specific activity of 182.08 U/mg protein. The molecular weight of the purified chitinase was 60 kDa, determined by a sodium dodecyl sulphate polyacrylamide gel electrophoresis. The optimum pH and temperature of purified chitinase were 5.6 and 50 °C, respectively. The chitinase enzyme was stable from pH 5 to 7.5 and stable up to 70 °C. The effect of activators and inhibitors was studied, Hg+, pb, EDTA, ethanol, methanol and acetone strongly inhibited the enzyme activity, while, metal ions such as Ca2+, Mn2+ and Na2+ highly increased chitinase activity. The purified chitinase produced by A. terreus inhibited the growth of Aspergillus niger, Aspergillus oryzae, Penicillum oxysporium, Rhizocotonia solani, Candida albicans and Fusarium solani, while did not inhibit the growth of Rhizopus oryzae. Moreover, the purified enzyme had antibacterial effects against some pathogenic bacteria such as; Staphylococcus aureus, Salmonella typhi and Pseudomonas aeruginosa, while, it had not any activity against Escherichia coli, Aeromonas hydrophila and Photobacterium damsela.

  9. [Suprapubic catheter insertion].

    Science.gov (United States)

    Neumann, Eva; Schwentner, Christian

    2016-01-01

    The suprapubic catheter enables a percutaneous drainage of urine. The insertion is made superior of the pubic bone through the abdominal wall into the bladder. It allows a permanent drainage of urine bypassing the urethra. The insertion of a suprapubic catheter requires knowledge and expertise. This paper summarizes the basic background and allows to follow the practical application step by step. PMID:26800072

  10. Tie rod insertion test

    CERN Multimedia

    B. LEVESY

    2002-01-01

    The superconducting coil is inserted in the outer vaccum tank and supported by a set of tie rods. These tie rods are made of titanium alloy. This test reproduce the final insertion of the tie rods inside the outer vacuum tank.

  11. High-capacity calcium-binding chitinase III from pomegranate seeds (Punica granatum Linn.) is located in amyloplasts

    OpenAIRE

    Lv, Chenyan; Masuda, Taro; Yang, Haixia; Sun, Lei; Zhao, Guanghua

    2011-01-01

    We have recently identified a new class III chitinase from pomegranate seeds (PSC). Interestingly, this new chitinase naturally binds calcium ions with high capacity and low affinity, suggesting that PSC is a Ca-storage protein. Analysis of the amino acid sequence showed that this enzyme is rich in acidic amino acid residues, especially Asp, which are responsible for calcium binding. Different from other known chitinases, PSC is located in the stroma of amyloplasts in pomegranate seeds. Trans...

  12. Purification and characterization of three chitinases and one beta-1,3-glucanase accumulating in the medium of cell suspension cultures of barley (Hordeum vulgare L.)

    DEFF Research Database (Denmark)

    Kragh, K.M.; Jacobsen, S.; Dalgaard Mikkelsen, J.;

    1991-01-01

    Three basic chitinases and one basic beta-1,3-glucanase were secreted into the medium when embryogenic cell suspensions of barley (Hordeum vulgare L.) cv. 'Igri' were cultured as undifferentiated aggregates in the presence of 2,4-D. The enzymes were purified by affinity and ion exchange...... chromatography. Two of the chitinases were identified as the previously described endochitinases T and C from barley grain. The third and novel chitinase, designated K, was the major basic chitinase in the medium constituting 4% of the soluble protein. Chitinase K was found to be a 33-kDa endochitinase with p......I at 8.7. Further analysis showed that this enzyme is also expressed in barley grain. The amino acid composition and five partial amino acid sequences covering 93 residues of chitinase K were determined. A high similarity was found between chitinase K and barley chitinase T and C as well as basic...

  13. Chitinase mRNA levels by quantitative PCR using the single standard DNA: acidic mammalian chitinase is a major transcript in the mouse stomach.

    Directory of Open Access Journals (Sweden)

    Misa Ohno

    Full Text Available Chitinases hydrolyze the β-1-4 glycosidic bonds of chitin, a major structural component of fungi, crustaceans and insects. Although mammals do not produce chitin or its synthase, they express two active chitinases, chitotriosidase (Chit1 and acidic mammalian chitinase (AMCase. These mammalian chitinases have attracted considerable attention due to their increased expression in individuals with a number of pathological conditions, including Gaucher disease, Alzheimer's disease and asthma. However, the contribution of these enzymes to the pathophysiology of these diseases remains to be determined. The quantification of the Chit1 and AMCase mRNA levels and the comparison of those levels with the levels of well-known reference genes can generate useful and biomedically relevant information. In the beginning, we established a quantitative real-time PCR system that uses standard DNA produced by ligating the cDNA fragments of the target genes. This system enabled us to quantify and compare the expression levels of the chitinases and the reference genes on the same scale. We found that AMCase mRNA is synthesized at extraordinarily high levels in the mouse stomach. The level of this mRNA in the mouse stomach was 7- to 10-fold higher than the levels of the housekeeping genes and was comparable to that the level of the mRNA for pepsinogen C (progastricsin, a major component of the gastric mucosa. Thus, AMCase mRNA is a major transcript in mouse stomach, suggesting that AMCase functions as a digestive enzyme that breaks down polymeric chitin and as part of the host defense against chitin-containing pathogens in the gastric contents. Our methodology is applicable to the quantification of mRNAs for multiple genes across multiple specimens using the same scale.

  14. Enzymatic properties of chitinase-producing antagonistic bacterium Paenibacillus chitinolyticus with various substrates.

    Science.gov (United States)

    Song, Yong-Su; Seo, Dong-Jun; Ju, Wan-Taek; Lee, Yong-Seong; Jung, Woo-Jin

    2015-12-01

    Various chitin substrates were used to investigate the properties of enzymes produced from the chitinase-producing bacterium Paenibacillus chitinolyticus MP-306 against phytopathogens. The MP-306 bacterium was incubated in nine culture media [crab shell powder chitin (CRS), chitin-protein complex powder (CPC), carboxymethyl-chitin powder (CMC), yeast extract only (YE), LB (Trypton, NaCl, and yeast extract), GT (Trypton, NaCl, and glucose), crab shell colloidal chitin (CSC), squid pen powder chitin (SPC), and cicada slough powder chitin (CSP)] at 30 °C for 3 days. Chitinase isozymes in CPC medium were expressed strongly as CN1, CN2, CN3, CN4, CN5, and CN6 bands on native-PAGE gels. Chitinase isozymes in CPC and CMC medium were expressed as 13 bands (CS1-CS13) on SDS-PAGE gels. Chitinase isozymes were expressed strongly on SDS-PAGE gels as two bands (CS6 and CS8) on YE and LB medium and 13 bands (CS1-CS13) on SPC medium. In crude enzyme, chitinase isozymes at pH 7 and pH 9 in chitin media appeared strongly on SDS-PAGE gels. Partial purified enzyme indicated high stability of enzyme activity at various temperatures and pHs in chitin medium, while these enzymes indicated low activity staining of enzyme on electrophoresis gels at various temperatures and pHs condition of chitin medium.

  15. Purification and characterization of chitinase from Bacillus circulans No.4.1.

    Science.gov (United States)

    Wiwat, C; Siwayaprahm, P; Bhumiratana, A

    1999-09-01

    Bacillus circulans No.4.1 produced a high level of chitinase when cells were grown in tryptic soy broth supplemented with 0.3% colloidal chitin at 35 degrees C for 5 days. Purification was carried out by protein precipitation with 80% saturation ammonium sulfate, anion-exchange chromatography with DEAE-Sephacel, and gel filtration with Sephadex G-100, sequentially. The purified enzyme could be demonstrated as a single band on SDS-PAGE, estimated to be 45 kDa. This enzyme could hydrolyze colloidal chitin, purified chitin, glycol chitin, carboxymethyl-chitin (CM-chitin), and 4-methylumbelliferyl-beta-D-N,N'-diacetylchitobioside [4-MU-(GlcNAc)(2)]. The optimal conditions for this chitinase were pH 8.0 and 40 degrees C. The isoelectric point of the chitinase was 5.1. The amino acid composition of the purified chitinase was determined. The initial 20 amino acid residues of the N-terminal were found to be alanine (A), proline (P), tryptophan (W), asparagine (N), serine (S), lysine (K), glycine (G), asparagine (N), tyrosine (Y), alanine (A), leucine (L), proline (P), tyrosine (Y), tyrosine (Y), arginine (R), glycine (G), alanine (A), tryptophan (W), alanine (A), and valine (V). Knowledge of these properties of chitinase from B. circulans No. 4.1 should be useful in the development of genetically engineered Bacillus sp. as biopesticides. PMID:10441726

  16. An investigation of a defensive chitinase against Fusarium oxysporum in pepper leaf tissue

    Directory of Open Access Journals (Sweden)

    Khemika S. Lomthaisong

    2008-01-01

    Full Text Available Plant chitinase is classified as a PR-protein involved in a defense mechanism against a pathogen. This research aims to investigate a specific type of chitinase which is produced by pepper in response to an early defense against Fusarium oxysporum, which causes wilt disease. The changes of chitinase isozyme patterns in the inter- and intracellular fluids in the leaf of four cultivars of pepper (Capsicum annuum L. at day 1, 3, 5, 7 and 10 from fungal inoculation were analysed using SDS-PAGE in polyacrylamide gel supplemented with glycol chitin as a substrate. The levels of disease severity in the four varieties of pepper were also compared with the isozyme patterns. The results showed that the resistance of pepper to F. oxysporum attack corresponded to the expression of ~70 kDa chitinase band (Chi-3 in the intercellular fluid. Therefore, such chitinase could possibly be used as a protein marker to identify the tolerant line and as a springboard for further study of wilt disease control.

  17. Characterization of two Listeria innocua chitinases of different sizes that were expressed in Escherichia coli.

    Science.gov (United States)

    Honda, Shotaro; Wakita, Satoshi; Sugahara, Yasusato; Kawakita, Masao; Oyama, Fumitaka; Sakaguchi, Masayoshi

    2016-09-01

    Two putative chitinase genes, lin0153 and lin1996, from the nonpathogenic bacterium Listeria innocua were expressed in Escherichia coli, and the gene products were characterized. The genes were close homologs of chitinases from the pathogenic bacterium Listeria monocytogenes, in which chitinases and chitin-binding proteins play important roles in pathogenesis in mice-infection models. The purified recombinant enzymes that are different in size, LinChi78 (lin0153 product) and LinChi35 (lin1996 product)-with molecular masses of 82 and 38 kDa, including vector-derived additional sequences, respectively-exhibited optimum catalytic activity under neutral and acidic conditions at 50 °C, respectively, and were stable over broad pH (4-11) and temperature (4-40 °C) ranges. LinChi35 displayed higher k cat and K M values for 4-nitrophenyl N,N-diacetyl-β-D-chitobioside [4NP-(GlcNAc)2] than LinChi78. Both enzymes produced primarily dimers from colloidal chitin as a substrate. However, LinChi78 and LinChi35 could hydrolyze oligomeric substrates in a processive exo- and nonprocessive endo-manner, respectively, and showed different reactivity toward oligomeric substrates. Both enzymes could bind chitin beads but were different in their binding ability toward crystalline α-chitin and cellulose. The structure-function relationships of these chitinases are discussed in reference to other bacterial chitinases. PMID:27138200

  18. Comparing Leaf and Root Insertion

    Directory of Open Access Journals (Sweden)

    Jaco Geldenhuys

    2010-07-01

    Full Text Available We consider two ways of inserting a key into a binary search tree: leaf insertion which is the standard method, and root insertion which involves additional rotations. Although the respective cost of constructing leaf and root insertion binary search trees trees, in terms of comparisons, are the same in the average case, we show that in the worst case the construction of a root insertion binary search tree needs approximately 50% of the number of comparisons required by leaf insertion.

  19. Degradation of chitin and chitosan by a recombinant chitinase derived from a virulent Aeromonas hydrophila isolated from diseased channel catfish

    Science.gov (United States)

    A chitinase was identified in extracellular products of a virulent Aeromonas hydrophila isolated from diseased channel catfish (Ictalurus punctatus). Bioactive recombinant chitinase (rChi-Ah) was produced in Escherichia coli. Purified rChi-Ah had optimal activity at temperature of 42°C and pH 6.5. T...

  20. EXPRESSION OF A CHITINASE GENE FROM SERRATIA-MARCESCENS IN LACTOCOCCUS-LACTIS AND LACTOBACILLUS-PLANTARUM

    NARCIS (Netherlands)

    BRURBERG, MB; HAANDRIKMAN, AJ; LEENHOUTS, KJ; VENEMA, G; NES, IF

    1994-01-01

    A chitinase gene from the Gram-negative bacterium Serratia marcescens BJL200 was cloned in Lactococcus lactis subsp. lactis MG1363 and in the silage inoculum strain Lactobacillus plantarum E19b. The chitinase gene was expressed as an active enzyme at a low level in Lactococcus lactis, when cloned in

  1. Biochemical characterization of Aspergillus niger Cfcl, a glycoside hydrolase family 18 chitinase that releases monomers during substrate hydrolysis

    NARCIS (Netherlands)

    van Munster, Jolanda M.; van der Kaaij, Rachel M.; Dijkhuizen, Lubbert; van der Maarel, Marc J. E. C.

    2012-01-01

    The genome of the industrially important fungus Aspergillus niger encodes a large number of glycoside hydrolase family 18 members annotated as chitinases. We identified one of these putative chitinases, Cfcl, as a representative of a distinct phylogenetic clade of homologous enzymes conserved in all

  2. Are mycoparasitism and chitinase production species or isolate dependent in Trichoderma ?

    Institute of Scientific and Technical Information of China (English)

    Szakacs G; Nagy V; Kovacs K

    2004-01-01

    @@ The relationship between taxonomic status of Trichoderma spp., chitinase production in solid substrate fermentation (SSF) on four media and mycoparasitism in dual culture (confrontation assay)against four plant pathogenic fungi was studied. Seventy five Trichoderma isolates belonging to 35species have been screened. The plant pathogenic fungi used in confrontation assay were Botrytis cinerea , Fusarium oxysporum f. sp. dianthi , Rhizoctonia solani and Sclerotinia sclerotiorum . The SSF media contained wheat bran, crude chitin (from crab shells, SIGMA) and salt solutions. The best performing isolates in mycoparasitism tests were Trichoderma flavofuscum, T. harzianum, T.inhamatum, T. koningii and T. strigosum. Some isolates exhibiting good mycoparasitism produced chitinase in SSF only at low or medium level. In contrary there were isolates with excellent extracellular chitinase production but their biocontrol potential did not belong to the leading group.Statistical methods have been used to evaluate the data.

  3. The Composite Insertion Electrode

    DEFF Research Database (Denmark)

    Atlung, Sven; Zachau-Christiansen, Birgit; West, Keld;

    1984-01-01

    The specific energy obtainable by discharge of porous insertion electrodes is limited by electrolyte depletion in thepores. This can be overcome using a solid ion conductor as electrolyte. The term "composite" is used to distinguishthese electrodes from porous electrodes with liquid electrolyte. ...... conductivities, the thicknessof the electrode, the volume fractions, and the slope of the potential curve.......The specific energy obtainable by discharge of porous insertion electrodes is limited by electrolyte depletion in thepores. This can be overcome using a solid ion conductor as electrolyte. The term "composite" is used to distinguishthese electrodes from porous electrodes with liquid electrolyte....... The theoretical basis for such electrodes is discussedand, using a simplified model, equations are derived to describe the distribution of potential and current duringdischarge/charge operation. Under the assumption that the insertion compound particles are small enough to ensureequilibrium, and that the local...

  4. ALS insertion devices

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS), the first US third generation synchrotron radiation source, is currently under construction at the Lawrence Berkeley Laboratory. The low-emittance, 1.5 GeV electron storage ring and the insertion devices are specifically designed to produce high brightness beams in the UV to soft X-Ray range. The planned initial complement of insertion devices includes four 4.6 m long undulators, with period lengths of 3.9 cm, 5.0 cm (2) and 8.0 cm, and a 2.9 m long wiggler of 16 cm period length. Undulator design is well advanced and fabrication has begun on the 5.0 cm and 8.0 cm period length undulators. This paper discusses ALS insertion device requirements; general design philosophy; and design of the magnetic structure, support structure/drive systems, control system and vacuum system. 18 refs., 9 figs., 5 tabs

  5. Isolation, purification, crystallization and preliminary crystallographic studies of chitinase from tamarind (Tamarindus indica) seeds.

    Science.gov (United States)

    Patil, Dipak N; Datta, Manali; Chaudhary, Anshul; Tomar, Shailly; Sharma, Ashwani Kumar; Kumar, Pravindra

    2009-04-01

    A protein with chitinase activity has been isolated and purified from tamarind (Tamarindus indica) seeds. N-terminal amino-acid sequence analysis of this protein confirmed it to be an approximately 34 kDa endochitinase which belongs to the acidic class III chitinase family. The protein was crystallized by the vapour-diffusion method using PEG 4000. The crystals belonged to the tetragonal space group P4(1), with two molecules per asymmetric unit. Diffraction data were collected to a resolution of 2.6 A.

  6. Study on the character of chitinase produced by Trichoderna spp.with measuring reducing sugar

    Institute of Scientific and Technical Information of China (English)

    LIU Kai-qi; XIANG Mei-mei; LIU Ren; ZENG Yong-san; LI Hua; JIANG Xin-yin; ZHANG Yue-li

    2004-01-01

    @@ A trusty and intuitionistic method for screening chitinase produced by Trichoderma spp. was developed. 38 isolates of Trichoderma spp. were cultured in liquid medium with chitin or colloidal chitin as the sole carbon source for 4 days. The supernatant of the fermented broth was mixed with colloidal chitin and heated in water-bath at 37℃ for 30 min, then 3,5-dinitrosalicylic acid reagent (DNS) was added to the mixture, and let them react for 10 min in water-bath. According to the different colour of the mixture, the isolates of Trichoderma spp. which can produce chitinase could be screened.

  7. Differential response of banana cultivars to F. oxysporum f. sp. cubense infection for Chitinase activity

    International Nuclear Information System (INIS)

    Six banana clones with varying levels of resistance were inoculated with conidial suspension of races 1 and 4 of Fusarium oxysporum f. sp. cubense. Chitanase activity in the corm and root tissues was monitored before and after infection to relate with the field resistance or susceptibility of banana cultivars. Resistant clones showed high constitutive chitinase activity in roots and a rapid response to infection. The results suggest that chitinase could be considered as part of a complex mechanism leading to disease resistance. (author). 5 refs, 8 figs

  8. Insertion in Persian

    Science.gov (United States)

    Kambuziya, Aliyeh Kord-e Zafaranlu; Dehghan, Masoud

    2011-01-01

    This paper investigates epenthesis process in Persian to catch some results in relating to vowel and consonant insertion in Persian lexicon. This survey has a close relationship to the description of epenthetic consonants and the conditions in which these consonants are used. Since no word in Persian may begin with a vowel, so that hiatus can't be…

  9. Inserting the CMS solenoid

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    The huge superconducting solenoid for CMS is inserted into the cryostat barrel. CMS uses the world's largest thin solenoid, in terms of energy stored, and is 12 m long, with a diameter of 6 m and weighing 220 tonnes. When turned on the magnet will produce a field strength of 4 T using superconducting niobium-titanium material at 4.5 K.

  10. Pixel detector insertion

    CERN Multimedia

    CMS

    2015-01-01

    Insertion of the Pixel Tracker, the 66-million-channel device used to pinpoint the vertex of each colliding proton pair, located at the heart of the detector. The geometry of CMS is a cylinder lying on its side (22 meters long and 15 meters high in dia

  11. The Role of Chitinase Production by Stenotrophomonas maltophilia Strain C3 in Biological Control of Bipolaris sorokiniana.

    Science.gov (United States)

    Zhang, Z; Yuen, G Y

    2000-04-01

    ABSTRACT The role of chitinase production by Stenotrophomonas maltophilia strain C3 in biological control of leaf spot on tall fescue (Festuca arundinacea), caused by Bipolaris sorokiniana, was investigated in vitro and in vivo. The filtrate of a broth culture of C3, with chitin as the carbon source, was separated into fractions. A high molecular-weight fraction (>8 kDa) was chitinolytic and more inhibitory than a low-molecular-weight, nonchitinolytic fraction to conidial germination and hyphal growth by B. sorokiniana and to leaf spot development. A protein fraction derived by ammonium sulfate precipitation and a chitinase fraction purified by chitin affinity chromatography also were chitinolytic and highly antifungal. The chitinolytic fractions caused swelling and vacuolation of conidia and discoloration, malformation, and degradation of germ tubes. When boiled, the chitinolytic fractions lost chitinase activity along with most of the antifungal properties. Two chitinase-deficient and two chitinase-reduced mutants of C3 were compared with the wild-type strain for inhibition of germination of B. sorokiniana conidia on tall fescue leaves and for suppression of leaf spot development in vivo. The mutants exhibited reduced antifungal activity and biocontrol efficacy, but did not lose all biocontrol activity. An aqueous extract of leaves colonized by wild-type C3 had higher chitinase activity than that of noncolonized leaves and was inhibitory to conidial germination. The addition of chitin to leaves along with the wild-type strain increased both chitinase and antifungal activity. The chitinase activity level of extracts from leaves colonized by a chitinase-deficient mutant of C3, with and without added chitin, was no higher than the background, and the extracts lacked antifungal activity. Chitinolysis appears to be one mechanism of biological control by strain C3, and it functions in concert with other mechanisms.

  12. Chitinolytic Bacteria Isolated from Chili Rhizosphere: Chitinase Characterization and Its Application as Biocontrol for Whitefly (Bemisia tabaci Genn.

    Directory of Open Access Journals (Sweden)

    Nisa R. Mubarik

    2010-01-01

    Full Text Available Problem statement: Chitin, a common constituent of insect exoskeleton, could be hydrolyzed by chitinase. The research was conducted to screen chitinolytic rhizobacteria isolated from rhizosphere of chilli pepper and to determine their chitinase activity in degrading chitin of whitefly, Bemisia tabaci Genn. (Hemiptera: Aleyrodidae. Whitefly is recognized as an important pest on many crops including chilli pepper. Approach: Screening and molecular identification based on 16S rRNA sequence of chitinolytic isolates, chitinase productions, measurement of chitinase activity, characterization of chitinase and effect of the chitinase treatment on whitefly were studied. Results: A total of 25 isolates of rhizobacteria formed a clear zone on solid chitin media. Two isolates, i.e., I.5 and I.21 isolates had the highest chitinolytic index. Based on sequence of 16S rRNA gene, the isolates of I.5 and I.21 were identified as Bacillus sp. and Bacillus cereus, respectively. The highest chitinolytic index and specific activity of I.5 isolate was 0.94 and 0.11 U mg-1 proteins, respectively. Maximum production of I.5 chitinase was occured after 36 h cultivation at 30°C and pH 7.0. The highest chitinolytic index and specific activity of I.21isolate was 0.75 and 0.114 U mg-1 proteins, respectively. Maximum production of I.21 chitinase was occured after 36 h cultivation at 55°C and pH 7.0. Cell culture and crude enzyme of the isolates were tested on chitin of B. tabaci and the effect was observed using a microscope and sterile water was used as a negative control. Hydrolytic observation showed that crude enzyme of I.21 isolate could degrade chitin of B. tabaci exoskeleton and the activity was better than that of I.5 isolate. Conclusion: Chitinase produced by Bacillus cereus I.21 strain has potential application as biocontrol agents for B. tabaci.

  13. Characterization of the Maize Chitinase Genes and Their Effect on Aspergillus flavus and Aflatoxin Accumulation Resistance.

    Science.gov (United States)

    Hawkins, Leigh K; Mylroie, J Erik; Oliveira, Dafne A; Smith, J Spencer; Ozkan, Seval; Windham, Gary L; Williams, W Paul; Warburton, Marilyn L

    2015-01-01

    Maize (Zea mays L.) is a crop of global importance, but prone to contamination by aflatoxins produced by fungi in the genus Aspergillus. The development of resistant germplasm and the identification of genes contributing to resistance would aid in the reduction of the problem with a minimal need for intervention by farmers. Chitinolytic enzymes respond to attack by potential pathogens and have been demonstrated to increase insect and fungal resistance in plants. Here, all chitinase genes in the maize genome were characterized via sequence diversity and expression patterns. Recent evolution within this gene family was noted. Markers from within each gene were developed and used to map the phenotypic effect on resistance of each gene in up to four QTL mapping populations and one association panel. Seven chitinase genes were identified that had alleles associated with increased resistance to aflatoxin accumulation and A. flavus infection in field grown maize. The chitinase in bin 1.05 identified a new and highly significant QTL, while chitinase genes in bins 2.04 and 5.03 fell directly beneath the peaks of previously published QTL. The expression patterns of these genes corroborate possible grain resistance mechanisms. Markers from within the gene sequences or very closely linked to them are presented to aid in the use of marker assisted selection to improve this trait. PMID:26090679

  14. Characterization of the Maize Chitinase Genes and Their Effect on Aspergillus flavus and Aflatoxin Accumulation Resistance.

    Directory of Open Access Journals (Sweden)

    Leigh K Hawkins

    Full Text Available Maize (Zea mays L. is a crop of global importance, but prone to contamination by aflatoxins produced by fungi in the genus Aspergillus. The development of resistant germplasm and the identification of genes contributing to resistance would aid in the reduction of the problem with a minimal need for intervention by farmers. Chitinolytic enzymes respond to attack by potential pathogens and have been demonstrated to increase insect and fungal resistance in plants. Here, all chitinase genes in the maize genome were characterized via sequence diversity and expression patterns. Recent evolution within this gene family was noted. Markers from within each gene were developed and used to map the phenotypic effect on resistance of each gene in up to four QTL mapping populations and one association panel. Seven chitinase genes were identified that had alleles associated with increased resistance to aflatoxin accumulation and A. flavus infection in field grown maize. The chitinase in bin 1.05 identified a new and highly significant QTL, while chitinase genes in bins 2.04 and 5.03 fell directly beneath the peaks of previously published QTL. The expression patterns of these genes corroborate possible grain resistance mechanisms. Markers from within the gene sequences or very closely linked to them are presented to aid in the use of marker assisted selection to improve this trait.

  15. A class V chitinase from Arabidopsis thaliana: gene responses, enzymatic properties, and crystallographic analysis

    DEFF Research Database (Denmark)

    Ohnuma, Takayuki; Numata, Tomoyuki; Osawa, Takuo;

    2011-01-01

    Expression of a class V chitinase gene (At4g19810, AtChiC) in Arabidopsis thaliana was examined by quantitative real-time PCR and by analyzing microarray data available at Genevestigator. The gene expression was induced by the plant stress-related hormones abscisic acid (ABA) and jasmonic acid (J...

  16. Differential enzymatic activity of common haplotypic versions of the human acidic mammalian chitinase protein

    NARCIS (Netherlands)

    M.A. Seibold; T.A. Reese; S. Choudhry; M.T. Salam; K. Beckman; C. Eng; A. Atakilit; K. Meade; M. Lenoir; H.G. Watson; S. Thyne; R. Kumar; K.B. Weiss; L.C. Grammer; P. Avila; R.P. Schleimer; J.V. Fahy; J. Rodriguez-Santana; W. Rodriguez-Cintron; R.G. Boot; D. Sheppard; F.D. Gilliland; R.M. Locksley; E.G. Burchard

    2009-01-01

    Mouse models have shown the importance of acidic mammalian chitinase activity in settings of Th2 inflammation. AMCase enzymatic activity was necessary for most of the inflammation present in an asthma mouse model. However, in settings of chitin exposure, AMCase-mediated cleavage of the inflammatory

  17. IN SILICO ANALYSIS OF CHITINASE PROMOTER ISOLATED FROM DROSERA ROTUNDIFOLIA L.

    Directory of Open Access Journals (Sweden)

    Dominika Ďurechová

    2014-02-01

    Full Text Available Chitinases occur in dozens of genes in the individual plant species and play diverse roles in plant growth and development, and during the plant defense to biotic and abiotic stress. Here we focused on isolation and in silico characterization of regulatory sequences of chitinase gene that belongs to the first isolated gene sequences from D. rotundifolia overall. For the isolation of the 739 bp sequence of chitinase promoter the genome walking approach was applied. The authenticity of the obtained fragment(s was verified by sequencing and sequence alignment ClustalW program. The core of the chitinase promoter was predicted by Neural Network Promoter Prediction program. In total the PLACE online available database identified 66 various cis-regulatory elements in the analyzed sequence. Some of them might be potentially bound by specific transcription factors, and regulate gene expression in specific plant tissues during the plant development or upon the pathogen attack, dehydration, cold or high salinity stress. However, further analyses are needed to reveal which out of predicted cis-elements participate in the true expression profile of isolated promoter in origin and transgenic plant organism.

  18. Studies on Exo-Chitinase Production from Trichoderma asperellum UTP-16 and Its Characterization.

    Science.gov (United States)

    Kumar, D Praveen; Singh, Rajesh Kumar; Anupama, P D; Solanki, Manoj Kumar; Kumar, Sudheer; Srivastava, Alok K; Singhal, Pradeep K; Arora, Dilip K

    2012-09-01

    The growth conditions for chitinase production by Trichoderma asperellum UTP-16 in solid state fermentation was optimized using response surface methodology based on central composite design. The chitinase production was optimized, using one-factor at a time approach, with six independent variables (temperature, pH, NaCl, incubation period, nitrogen and carbon sources) and 3.31 Units per gram dry substrate (U gds(-1)) exo-chitinase yield was obtained. A 21.15% increase was recorded in chitinase activity (4.01 U gds(-1)) through surface response methodology, indicates that it is a powerful and rapid tool for optimization of physical and nutritional variables. Further, efficiency of crude enzyme was evaluated against phytopathogenic Fusarium spp. and a mycelial growth inhibition up to 3.5-6.5 mm was achieved in well diffusion assay. These results could be supplemented as basic information for the development of enzyme based formulation of T. asperellum UTP-16 and its use as a biocontrol agent. PMID:23997329

  19. Enzyme kinetics of hevamine, a chitinase from the rubber tree Hevea brasiliensis

    NARCIS (Netherlands)

    Bokma, Evert; Barends, Thomas; Terwisscha van Scheltinga, Anke C.; Dijkstra, Bauke W.; Beintema, Jaap J.

    2000-01-01

    The enzyme kinetics of hevamine, a chitinase from the rubber tree Hevea brasiliensis, were studied in detail with a new enzyme assay. In this assay, the enzyme reaction products were derivatized by reductive coupling to a chromophore, Products mere separated by HPLC and the amount of product was cal

  20. [The study of mycolytic properties of aerobic spore-forming bacteria producing extracellular chitinases].

    Science.gov (United States)

    Aktuganov, G E; Melent'ev, A I; Galimzianova, N F; Shirokov, A V

    2008-01-01

    The mycolytic activity of 27 strains of antagonistic bacilli belonging to two taxonomic groups (18 strains of Bacillus subtilis and 9 strains of Paenibacillus ehimensis) capable of induced synthesis of chitinolytic enzymes was studied. Most of the B. subtilis strains neither displayed visible mycolytic effects on the phytopathogenic fungus Bipolaris sorokiniana in vitro, nor produced chitinases in the presence of an auto-claved mycelium. On the contrary, P. ehimensis strains grown under conditions favorable for induction of chitinases and other hydrolases exhibited a pronounced lytic effect on B. sorokiniana and actively grew by utilizing mycelium as the sole source of carbon and nitrogen. Comparison of the mycolytic activities of extracellular hydrolases in the studied strains demonstrated low correlation between chitinase production and the ability of the strains to degrade the cell walls of B. sorokiniana. Characterization of enzyme profiles in the studied strains revealed that beta-1,3-glucanase was a more significant factor than chitinase for determining the mycolytic potential of bacteria and their ability to utilize the mycelium of phytopathogenic fungi as a growth substrate.

  1. CHITINASE-B FROM SERRATIA-MARCESCENS-BJL200 IS EXPORTED TO THE PERIPLASM WITHOUT PROCESSING

    NARCIS (Netherlands)

    BRURBERG, MB; EIJSINK, VGH; HAANDRIKMAN, AJ; VENEMA, G; NES, IF

    1995-01-01

    A gene encoding a chitinase from Serratia marcescens BJL200 was cloned and expressed in Escherichia coli and S. marcescens. Nucleotide sequencing revealed an open reading frame encoding a 55.5 kDa protein of 499 amino acids without a typical signal peptide for export. The cellular localization of th

  2. Crystallization of Hevamine, an Enzyme with Lysozyme/Chitinase Activity from Hevea brasiliensis Latex

    NARCIS (Netherlands)

    ROZEBOOM, HJ; BUDIANI, A; BEINTEMA, JJ

    1990-01-01

    Hevamine, an enzyme with both lysozyme and chitinase activity, was isolated and purified from Hevea brasiliensis (rubber tree) latex. The enzyme (molecular weight 29,000) is homologous to certain “pathogenesis-related” proteins from plants, but not to hen egg-white or phage T4 lysozyme. To investiga

  3. Use of Metarhizium anisopliae Chitinase Genes for Genotyping and Virulence Characterization

    Directory of Open Access Journals (Sweden)

    Saliou Niassy

    2013-01-01

    Full Text Available Virulence is the primary factor used for selection of entomopathogenic fungi (EPF for development as biopesticides. To understand the genetic mechanisms underlying differences in virulence of fungal isolates on various arthropod pests, we compared the chitinase genes, chi2 and chi4, of 8 isolates of Metarhizium anisopliae. The clustering of the isolates showed various groups depending on their virulence. However, the analysis of their chitinase DNA sequences chi2 and chi4 did not reveal major divergences. Although their protein translates have been implicated in fungal virulence, the predicted protein structure of chi2 was identical for all isolates. Despite the critical role of chitin digestion in fungal infection, we conclude that chi2 and chi4 genes cannot serve as molecular markers to characterize observed variations in virulence among M. anisopliae isolates as previously suggested. Nevertheless, processes controlling the efficient upregulation of chitinase expression might be responsible for different virulence characteristics. Further studies using comparative “in vitro” chitin digestion techniques would be more appropriate to compare the quality and the quantity of chitinase production between fungal isolates.

  4. Stimulatory effects of chitinase on growth and immune defense of orange-spotted grouper (Epinephelus coioides).

    Science.gov (United States)

    Zhang, Yanhong; Feng, Shaozhen; Chen, Jun; Qin, Chaobin; Lin, Haoran; Li, Wensheng

    2012-05-01

    Chitinase, belonging to either family 18 or family 19 of the glycosylhydrolases, hydrolyze chitin into oligosaccharides. In the present study, the cDNA fragment encoding orange-spotted grouper (Epinephelus coioides) chitinase1 was subcloned into pPIC3.5K vector and expressed in Pichia pastoris GS115. The results showed that a band with the size of about 53 kDa could be detected by SDS-PAGE and Western blot. The recombinant protein of grouper chitinase1 (rgChi1) was added into the fish diet containing shrimp shell chitin for feeding experiment lasting 8 weeks. The weight of orange-spotted grouper, fed with diets containing rgChi1 at 0, 5, 10 and 20 μg/g was calculated on the 2nd, 4th, 6th and 8th weeks, and difference in growth rates was first observed in the 6th week of the feeding period and it kept until the end of the feeding experiment. At the end of 8 weeks feeding trial, the percent weight gain (PWG), growth rate (GR) and specific growth rate (SGR) of fish fed with 10 and 20 μg rgChi1/g feed were significantly higher compared to the control group. The neuropeptide Y (NPY), growth-hormone-releasing hormone (GHRH), growth-hormone (GH), interleukin-1beta (IL-1β), cyclooxygenase-2 (COX-2), superoxide dismutase (SOD) (Cu/Zn) and SOD (Mn) mRNA expression of fish fed with diet containing 10 μg/g or/and 20 μg/g rgChi1 were obviously higher than the control group. The lysozyme (LZM) and total SOD activity of fish fed with diet containing rgChi1 at 10 and 20 μg/g were significantly higher than that of the control. The aspartate aminotransferase (AST)/glutamic oxalacetic transaminases (GOT) activity in 20 μg/g group decreased compared to the control group. These results indicated that the grouper chitinase1 was successfully produced using the P. pastoris expression system and the recombinant protein had obvious effects on growth and immune defense. The mRNA expression and protein secretion of grouper chitinase1 and chitinase2 were significantly stimulated in

  5. Purification and characterization of chitinase from Alcaligenes faecalis AU02 by utilizing marine wastes and its antioxidant activity

    OpenAIRE

    Annamalai, Neelamegam; Veeramuthu Rajeswari, Mayavan; Vijayalakshmi, Shanmugam; Balasubramanian, Thangavel

    2011-01-01

    Marine waste is an abundant renewable source for the recovery of several value added metabolites with potential industrial applications. This study describes the production of chitinase on marine waste, with the subsequent use of the same marine waste for the extraction of antioxidants. A chitinase-producing bacterium isolated from seafood effluent was identified as Alcaligenes faecalis AU02. Optimal chitinase production was obtained in culture conditions of 37°C for 72 h in 100 ml medium con...

  6. MECHANISM AND HYDROPHOBIC FORCES DRIVING MEMBRANE PROTEIN INSERTION OF SUBUNIT II OF CYTOCHROME BO OXIDASE

    Science.gov (United States)

    Celebi, Nil; Dalbey, Ross E.; Yuan, Jijun

    2009-01-01

    Subunit II (CyoA) of cytochrome bo oxidase, which spans the inner membrane twice in bacteria, has several unusual features in membrane biogenesis. It is synthesized with an amino-terminal signal peptide. In addition, distinct pathways are used to insert the two ends of the protein. The amino-terminal domain is inserted by the YidC pathway whereas the large carboxyl-terminal domain is translocated by the SecYEG pathway. Insertion of the protein is also pmf-independent. In this study we examined the topogenic requirements and mechanism of insertion of CyoA in bacteria. We find that both the signal peptide and the first membrane spanning region are required for insertion of the amino-terminal periplasmic loop. The pmf-independence of insertion of the first periplasmic loop is due to the loop’s neutral net charge. We observe also that the introduction of negatively charged residues into the periplasmic loop makes insertion pmf dependent, whereas the addition of positively charged residues prevents insertion unless the pmf is abolished. Insertion of the carboxyl-terminal domain in the full-length CyoA occurs by a sequential mechanism even when the CyoA amino and carboxyl-terminal domains are swapped with other domains. However, when a long spacer peptide is added to increase the distance between the amino-terminal and carboxyl-terminal domains, insertion no longer occurs by a sequential mechanism. PMID:18155041

  7. Chitinase but N-acetyl-β-D-glucosaminidase production correlates to the biomass decline in Penicillium and Aspergillus species.

    Science.gov (United States)

    Pusztahelyi, Tünde; Pócsi, István

    2014-06-01

    Hydrolytic enzyme production is typical of the autolysis in filamentous fungi; however, less attention has been given to the physiological role of the enzymes. Here, the aim was to investigate the possible relation of the chitinolytic enzymes to the changes in the biomass in some filamentous fungi of high importance for pharmaceutical or food industry. In Penicillium and Aspergillus filamentous fungi, which showed different characteristics in submerged cultures, the growth and biomass decline rates were calculated and correlated to the chitinase and N-acetyl-β-D-glucosaminidase enzyme productions. Correlation was found between the biomass decrease rate and the chitinase level at the stationary growth phase; while chitinase production covariates negatively with N-acetyl-β-D-glucosaminidase activities. The chitinase production and the intensive autolysis hindered the production of N-acetyl-β-D-glucosaminidase and, therefore, could hinder the cell death in the cultures.

  8. Detection of chitinolytic enzymes with different substrate specificity in tissues of intact sundew (Drosera rotundifolia L.): chitinases in sundew tissues.

    Science.gov (United States)

    Libantová, Jana; Kämäräinen, Terttu; Moravcíková, Jana; Matusíková, Ildikó; Salaj, Jan

    2009-05-01

    The round-leaf sundew (Drosera rotundifolia L.) is a carnivorous plant expressing a wide range of chitinolytic enzymes playing role in many different processes. In this study the intact plants were analyzed for the presence of chitinase transcripts and chitinolytic activities in different organs. In situ hybridization with chitnase fragment as a probe has revealed the presence of chitinases in the mesophyll cells of leaves and vascular elements of stems of healthy, non-stressed plants. More pronounced expression was observed in cortex and stele cells of roots as well as in ovules and anthers of reproductive organs. Similarly, higher chitinase enzyme activity was typical for flowers and roots suggesting a more specific role of chitinases in these tissues. In addition to endochitinases of different substrate specificities, chitobiosidases contributed to overall chitinolytic activity of tissue extracts. The activity of chitobiosidases was again typical for flowers and roots, while their role in plant physiology remains to be elucidated. PMID:18437530

  9. Transformation of indica rice with plasmid pBGll21 containing a tobacco endo-chitinase gene I

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Several plasmids, which were suitable for cereals transformation, have been reported. In the study, rice was transformed by a new plasmid pBGll21 containing a tobacco endo-chitinase gene ( TchiB ).

  10. X-Ray Crystal Structure of the Full Length Human Chitotriosidase (CHIT1 Reveals Features of Its Chitin Binding Domain.

    Directory of Open Access Journals (Sweden)

    Firas Fadel

    Full Text Available Chitinases are enzymes that catalyze the hydrolysis of chitin. Human chitotriosidase (CHIT1 is one of the two active human chitinases, involved in the innate immune response and highly expressed in a variety of diseases. CHIT1 is composed of a catalytic domain linked by a hinge to its chitin binding domain (ChBD. This latter domain belongs to the carbohydrate-binding module family 14 (CBM14 family and facilitates binding to chitin. So far, the available crystal structures of the human chitinase CHIT1 and the Acidic Mammalian Chitinase (AMCase comprise only their catalytic domain. Here, we report a crystallization strategy combining cross-seeding and micro-seeding cycles which allowed us to obtain the first crystal structure of the full length CHIT1 (CHIT1-FL at 1.95 Å resolution. The CHIT1 chitin binding domain (ChBDCHIT1 structure shows a distorted β-sandwich 3D fold, typical of CBM14 family members. Accordingly, ChBDCHIT1 presents six conserved cysteine residues forming three disulfide bridges and several exposed aromatic residues that probably are involved in chitin binding, including the highly conserved Trp465 in a surface- exposed conformation. Furthermore, ChBDCHIT1 presents a positively charged surface which may be involved in electrostatic interactions. Our data highlight the strong structural conservation of CBM14 family members and uncover the structural similarity between the human ChBDCHIT1, tachycitin and house mite dust allergens. Overall, our new CHIT1-FL structure, determined with an adapted crystallization approach, is one of the few complete bi-modular chitinase structures available and reveals the structural features of a human CBM14 domain.

  11. X-Ray Crystal Structure of the Full Length Human Chitotriosidase (CHIT1) Reveals Features of Its Chitin Binding Domain

    Science.gov (United States)

    Fadel, Firas; Zhao, Yuguang; Cousido-Siah, Alexandra; Ruiz, Francesc X.; Mitschler, André; Podjarny, Alberto

    2016-01-01

    Chitinases are enzymes that catalyze the hydrolysis of chitin. Human chitotriosidase (CHIT1) is one of the two active human chitinases, involved in the innate immune response and highly expressed in a variety of diseases. CHIT1 is composed of a catalytic domain linked by a hinge to its chitin binding domain (ChBD). This latter domain belongs to the carbohydrate-binding module family 14 (CBM14 family) and facilitates binding to chitin. So far, the available crystal structures of the human chitinase CHIT1 and the Acidic Mammalian Chitinase (AMCase) comprise only their catalytic domain. Here, we report a crystallization strategy combining cross-seeding and micro-seeding cycles which allowed us to obtain the first crystal structure of the full length CHIT1 (CHIT1-FL) at 1.95 Å resolution. The CHIT1 chitin binding domain (ChBDCHIT1) structure shows a distorted β-sandwich 3D fold, typical of CBM14 family members. Accordingly, ChBDCHIT1 presents six conserved cysteine residues forming three disulfide bridges and several exposed aromatic residues that probably are involved in chitin binding, including the highly conserved Trp465 in a surface- exposed conformation. Furthermore, ChBDCHIT1 presents a positively charged surface which may be involved in electrostatic interactions. Our data highlight the strong structural conservation of CBM14 family members and uncover the structural similarity between the human ChBDCHIT1, tachycitin and house mite dust allergens. Overall, our new CHIT1-FL structure, determined with an adapted crystallization approach, is one of the few complete bi-modular chitinase structures available and reveals the structural features of a human CBM14 domain. PMID:27111557

  12. ENDOSCOPIC GROMMET INSERTION OUR EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Balasubramanian Thiagarajan

    2012-03-01

    Full Text Available Grommet insertion the commonest surgical procedure next only to circumcision is usually performed using an operating microscope 1. Authors have been using 4 mm 0 degree nasalendoscopes to perform this procedure during the last 5 years. This is a report of their experience in using endoscope inlieu of microscope in performing this surgery. This study makes a comparative analysis of Endoscopic Grommet insertion viz a viz Microscopic Grommet insertion. For this comparative analysis one year (2009 data base of Government Stanley Medical College Chennai India was used. This study reveals that Endoscopic Grommet insertion compared favorably with Microscopic Grommet insertion in all aspects with certain obvious advantages.

  13. Contribution of Chitinase A’s C-Terminal Vacuolar Sorting Determinant to the Study of Soluble Protein Compartmentation

    Directory of Open Access Journals (Sweden)

    Egidio Stigliano

    2014-06-01

    Full Text Available Plant chitinases have been studied for their importance in the defense of crop plants from pathogen attacks and for their peculiar vacuolar sorting determinants. A peculiarity of the sequence of many family 19 chitinases is the presence of a C-terminal extension that seems to be important for their correct recognition by the vacuole sorting machinery. The 7 amino acids long C-terminal vacuolar sorting determinant (CtVSD of tobacco chitinase A is necessary and sufficient for the transport to the vacuole. This VSD shares no homology with other CtVSDs such as the phaseolin’s tetrapeptide AFVY (AlaPheValTyr and it is also sorted by different mechanisms. While a receptor for this signal has not yet been convincingly identified, the research using the chitinase CtVSD has been very informative, leading to the observation of phenomena otherwise difficult to observe such as the presence of separate vacuoles in differentiating cells and the existence of a Golgi-independent route to the vacuole. Thanks to these new insights in the endoplasmic reticulum (ER-to-vacuole transport, GFPChi (Green Fluorescent Protein carrying the chitinase A CtVSD and other markers based on chitinase signals will continue to help the investigation of vacuolar biogenesis in plants.

  14. Ozone and ultraviolet B effects on the defense-related proteins beta-1,3-glucanase and chitinase in tobacco

    International Nuclear Information System (INIS)

    The air pollutant ozone is a potent abiotic inducer of defense-related enzymes such as pathogenesis-related proteins. Here we report on the accumulation of beta-1,3-glucanase and chitinase in Nicotiana tabacumL. treated with ozone and ultraviolet B radiation, singly and in combination, under a simulated sunlight spectrum. Ozone (0.16 mu L . L-1, 2 x 5 h) induced the basic isoforms of beta-1,3-glucanase in both, ozone-sensitive (Eel W3) and -tolerant (Bel B) cultivars, while chitinase was only affected in cv. Bel W3. Ultraviolet B radiation (7.5 MED) alone did not lead to beta-1,3-glucanase or chitinase induction. In combined treatments ultraviolet B increased the ozone-dependent lesion formation and reduced chitinase accumulation in the sensitive cv. Bel W3. Analysis of the intercellular washing fluid of ozone-treated plants revealed the accumulation of a major ozone-related protein (O(3)R-1) of 28 kDa within 32 h. Microsequence analysis of two tryptic peptides showed 100 % homology to acidic chitinase PR-3b. These results indicate that basic beta-1,3-glucanase and chitinase are distinctly regulated in ozone and ultraviolet B treated tobacco, and that ultraviolet B radiation with a similar UV edge as the solar spectrum does not lead to an accumulation of basic pathogenesis-related proteins

  15. Two cold-induced family 19 glycosyl hydrolases from cherimoya (Annona cherimola) fruit: an antifungal chitinase and a cold-adapted chitinase.

    Science.gov (United States)

    Goñi, Oscar; Sanchez-Ballesta, María T; Merodio, Carmen; Escribano, María I

    2013-11-01

    Two cold-induced chitinases were isolated and purified from the mesocarp cherimoyas (Annona cherimola Mill.) and they were characterised as acidic endochitinases with a Mr of 24.79 and 47.77kDa (AChi24 and AChi48, respectively), both family 19 glycosyl hydrolases. These purified chitinases differed significantly in their biochemical and biophysical properties. While both enzymes had similar optimal acidic pH values, AChi24 was enzymatically active and stable at alkaline pH values, as well as displaying an optimal temperature of 45°C and moderate thermostability. Kinetic studies revealed a great catalytic efficiency of AChi24 for oligomeric and polymeric substrates. Conversely, AChi48 hydrolysis showed positive co-operativity that was associated to a mixture of different functional oligomeric states through weak transient protein interactions. The rise in the AChi48 kcat at increasing enzyme concentrations provided evidence of its oligomerisation. AChi48 chitinase was active and stable in a broad acidic pH range, and while it was relatively labile as temperatures increased, with an optimal temperature of 35°C, it retained about 50% of its maximal activity from 5 to 50°C. Thermodynamic characterisation reflected the high kcat of AChi48 and the remarkably lower ΔH(‡), ΔS(‡) and ΔG(‡) values at 5°C compared to AChi24, indicating that the hydrolytic activity of AChi48 was less thermodependent. In vitro functional studies revealed that AChi24 had a strong antifungal defence potential against Botrytis cinerea, whereas they displayed no cryoprotective or antifreeze activity. Hence, based on biochemical, thermodynamic and functional data, this study demonstrates that two acidic endochitinases are induced at low temperatures in a subtropical fruit, and that one of them acts in an oligomeric cold-adapted manner. PMID:23890591

  16. Comparative molecular evolution of Trichoderma chitinases in response to mycoparasitic interactions

    DEFF Research Database (Denmark)

    Ihrmark, Katarina; Asmail, Nashwan; Ubhayasekera, Wimal;

    2010-01-01

    Certain species of the fungal genus Trichoderma are potent mycoparasites and are used for biological control of fungal diseases on agricultural crops. In Trichoderma, whole-genome sequencing reveal between 20 and 36 different genes encoding chitinases, hydrolytic enzymes that are involved...... in the mycoparasitic attack. Sequences of Trichoderma chitinase genes chi18-5, chi18-13, chi18-15 and chi18-17, which all exhibit specific expression during mycoparasitism-related conditions, were determined from up to 13 different taxa and studied with regard to their evolutionary patterns. Two of them, chi18......-usage and contains five codons that evolve under positive selection and three groups of co-evolving sites. Regions of high amino acid variability are preferentially localized to substrate- or product side of the catalytic clefts. Differences in amino acid diversity/conservation patterns between different Trichoderma...

  17. Characterization of a novel chitinase, DkChi, from Dendrolimus kikuchii nucleopolyhedrovirus.

    Science.gov (United States)

    Wang, Qinghua; Qu, Liangjian; Zhang, Zhilin; Wang, Yuzhu; Zhang, Yongan

    2013-12-01

    Dendrolimus kikuchii Matsumura nucleopolyhedrovirus (DkNPV) is a novel nucleopolyhedrovirus strain that has exhibited high potential as biological control agent against D. kikuchii. In this work, a 1755-bp DkChi gene with sequence homology to a chitinase gene was cloned from the genomic DNA of DkNPV using a DNA fragment library. The DkChi gene, encoding 558 residues protein with a predicted mass of 61.6 kDa, was expressed at high levels in Escherichia coli and purified by affinity chromatography. We confirmed that the prepared protein was the DkChi protein by mass spectrometry analysis. Enzyme activity analysis showed that DkChi had both endo- and exo-chitinase activities. Interestingly, the DkChi protein displayed a strong insecticidal activity against Spodoptera exigua, Hyphantria cunea, Helicoverpa armigera and Lymantria dispar. The results suggest that DkChi is a good candidate protein for significantly contributing to pest control.

  18. ISOLATION AND CHARACTERIZATION OF CHITINASE GENE FROM THE UNTRADITIONAL PLANT SPECIES

    Directory of Open Access Journals (Sweden)

    Dominika Ďurechová

    2013-02-01

    Full Text Available Round-leaf sundew (Drosera rotundifolia L. from Droseraceae family belongs among a few plant species with strong antifungal potential. It was previously shown that chitinases of carnivorous plant species may play role during the insect prey digestion, when hard chitin skeleton is being decomposed. As many phytopathogenic fungi contain chitin in their cell wall our attention in this work was focused on isolation and in silico characterization of genomic DNA sequence of sundew chitinase gene. Subsequently this gene was fused to strong constitutive CaMV35S promoter and cloned into the plant binary vector pBinPlus and tested in A. tumefaciens LBA 4404 for its stability. Next, when transgenic tobacco plants are obtained, increasing of their antifungal potential will be tested.

  19. Chitinase-3-like-1/YKL-40 as marker of circulating tumor cells

    OpenAIRE

    Hamilton, Gerhard; Rath, Barbara; Burghuber, Otto

    2015-01-01

    Ex vivo expansion of circulating tumor cells (CTCs) of small cell lung cancer (SCLC) patients enabled systematic screening of secreted cytokines. Permanent CTC cultures of different patients shared secretion of chitinase-3-like-1 (CHI3L1)/YKL-40, known to be upregulated in a range of tumor entities and to be associated with increased metastasis and decreased survival. This protein lacks enzymatic activity and its mechanism of promoting tumor dissemination has not been resolved. Results from S...

  20. Effect of Chitinase-Producing Strain V-8 on 3ontrolling Cotton Fusarium Wilt

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to screen endophytic bacteria which is antag- onistic to cotton Fusarium wilt. [Method] Fresh cotton plants collected from cotton- growing areas in Jingzhou City, Hubei Province were used as experimental materials to isolate endophytic bacteria. Through chitinase test and co-culturing both micro-or- ganisms side by side on the same PDA culture plate, antagonistic strains to cotton Fusarium wilt were screened. [Result] A total of 83 bacterial isolates were obtained from cotton plants grown in the fields, six of which were chitinase-productive bacte- ria. Through chitinase test and co-culturing both micro-organisms side by side on the same PDA culture plate, strain V-8 which had the strongest antagonistic effect on Fusarium oxysporum f. sp. vasinfectum was screened. Strain V-8 had a wider anti- fungal spectrum with certain inhibitory effect on all the six important pathogenic fungi including Fusarium oxysporum f. sp niveum; it colonized stably in the rhizospheric soil of cotton, with a colonization density of up to 6.2x10s cfu/g fifty days after inoc- ulation; the relative effect on controlling cotton Fusarium wilt in pot test was 73.2%. The Findings of this study suggested that strain V-8 had great potential for biological control of cotton Fusarium wilt and could be taken as a substantial material for the cloning of chitinase genes. [Conclusion] The results from this study provides bases for the control of cotton fusarium wilt, as well as the exploitation of endophytic bac- teria resources in cotton and the development of novel biological pesticides.

  1. Chitinase activities, scab resistance, mycorrhization rates and biomass of own-rooted and grafted transgenic apple

    Directory of Open Access Journals (Sweden)

    Tina Schäfer

    2012-01-01

    Full Text Available This study investigated the impact of constitutively expressed Trichoderma atroviride genes encoding exochitinase nag70 or endochitinase ech42 in transgenic lines of the apple cultivar Pinova on the symbiosis with arbuscular mycorrhizal fungi (AMF. We compared the exo- and endochitinase activities of leaves and roots from non-transgenic Pinova and the transgenic lines T386 and T389. Local and systemic effects were examined using own-rooted trees and trees grafted onto rootstock M9. Scab susceptibility was also assessed in own-rooted and grafted trees. AMF root colonization was assessed microscopically in the roots of apple trees cultivated in pots with artificial substrate and inoculated with the AMF Glomus intraradices and Glomus mosseae. Own-rooted transgenic lines had significantly higher chitinase activities in their leaves and roots compared to non-transgenic Pinova. Both of the own-rooted transgenic lines showed significantly fewer symptoms of scab infection as well as significantly lower root colonization by AMF. Biomass production was significantly reduced in both own-rooted transgenic lines. Rootstock M9 influenced chitinase activities in the leaves of grafted scions. When grafted onto M9, the leaf chitinase activities of non-transgenic Pinova (M9/Pinova and transgenic lines (M9/T386 and M9/T389 were not as different as when grown on their own roots. M9/T386 and M9/T389 were only temporarily less infected by scab than M9/Pinova. M9/T386 and M9/T389 did not differ significantly from M9/Pinova in their root chitinase activities, AMF root colonization and biomass.

  2. Isolation and Purifi cation of Chitinase Bacillus sp. D2 Isolated from Potato Rhizosfer

    Directory of Open Access Journals (Sweden)

    Sebastian Margino

    2015-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Potato Cyst Nematodes (Globodera rostochiensis is one of the important potato’s pests and caused economic looses up to 70% in the several centrals of potato plantations in Indonesia. Potato Cyst Nematodes (PCN shell component of egg shell containing chitin (inner layer and vitelline/protein (outer layer, so the purpose of research was to fi nd out of chitin degrading bacteria for controlling of egg’s PCN by cutting of their life cycle. The results showed that Bacillus sp. D2 isolated from potato rhizosphere could produce extra cellular chitinase in the medium containing of 0.20% colloidal chitin and fermented for 72 hours. Result of chitinase purifi cation using ammonium sulphate precipitation and DEAE-Cellulose ion-exchange chromatography showed a specifi c activity 2691,052 U/mg and analyzing using SDS-PAGE 12.5% resulted in molecular weight 30 kDa. The apparent Km and Vmax of chitinase towards colloidal chitin were 2 mg/ml and 2.2 μg/h, respectively.  

  3. Optimization of Chitinase Production by Bacillus pumilus Using Plackett-Burman Design and Response Surface Methodology

    Science.gov (United States)

    Tasharrofi, Noshin; Adrangi, Sina; Fazeli, Mehdi; Rastegar, Hossein; Khoshayand, Mohammad Reza; Faramarzi, Mohammad Ali

    2011-01-01

    A soil bacterium capable of degrading chitin on chitin agar plates was isolated and identified as Bacillus pumilus isolate U5 on the basis of 16S rDNA sequence analysis. In order to optimize culture conditions for chitinase production by this bacterium, a two step approach was employed. First, the effects of several medium components were studied using the Plackett-Burman design. Among various components tested, chitin and yeast extract showed positive effect on enzyme production while MgSO4 and FeSO4 had negative effect. However, the linear model proved to be insufficient for determining the optimum levels for these components due to a highly significant curvature effect. In the second step, Box-Behnken response surface methodology was used to determine the optimum values. It was noticed that a quadratic polynomial equation fitted he experimental data appropriately. The optimum concentrations for chitin, yeast extract, MgSO4 and FeSO4 were found to be 4.76, 0.439, 0.0055 and 0.019 g/L, respectively, with a predicted value of chitinase production of 97.67 U/100 mL. Using this statistically optimized medium, the practical chitinase production reached 96.1 U/100 mL. PMID:24250411

  4. Purification and characterization of an antifungal chitinase from Bacillus sp.SL-13

    Institute of Scientific and Technical Information of China (English)

    Chen; Shan

    2014-01-01

    Bacillus sp.SL-13 produced antifungal proteins.The growth of the plant-pathogenic fungi Rhizoctonia solani was considerably inhibited by the presence of the SL-13 culture supernatant.The proteins were purified by DEAE-Sepharose fast flow ion exchange column chromatography and Sephadex G-75 gel filtration,and the main antifungal protein was purified to be chitinase.The molecular weight of chitinase was estimated to be 36 kD by 12%SDS PAGE.The optimal pH and temperature for the chitinase was 7.0 and 50℃.It demonstrated that the enzyme was stable from pH 5 to 9 and form 40?C to 60℃.The enzyme still kept 70%activity when incubated at 121℃,0.11MPa up to 20 minutes and the enzyme is also not lost the activity when treated with protease K and ultraviolet radiation for 1.5hours.It is very suitable for the use in a relatively unstable environment,exhibiting effective biological control.

  5. Facility target insert shielding assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mocko, Michal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-06

    Main objective of this report is to assess the basic shielding requirements for the vertical target insert and retrieval port. We used the baseline design for the vertical target insert in our calculations. The insert sits in the 12”-diameter cylindrical shaft extending from the service alley in the top floor of the facility all the way down to the target location. The target retrieval mechanism is a long rod with the target assembly attached and running the entire length of the vertical shaft. The insert also houses the helium cooling supply and return lines each with 2” diameter. In the present study we focused on calculating the neutron and photon dose rate fields on top of the target insert/retrieval mechanism in the service alley. Additionally, we studied a few prototypical configurations of the shielding layers in the vertical insert as well as on the top.

  6. Impedance calculation for ferrite inserts

    Energy Technology Data Exchange (ETDEWEB)

    Breitzmann, S.C.; Lee, S.Y.; /Indiana U.; Ng, K.Y.; /Fermilab

    2005-01-01

    Passive ferrite inserts were used to compensate the space charge impedance in high intensity space charge dominated accelerators. They study the narrowband longitudinal impedance of these ferrite inserts. they find that the shunt impedance and the quality factor for ferrite inserts are inversely proportional to the imaginary part of the permeability of ferrite materials. They also provide a recipe for attaining a truly passive space charge impedance compensation and avoiding narrowband microwave instabilities.

  7. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    The domain concept, originally suggested by Schmidt-Rohr in the 1930’s (as credited in Fishman’s writings in the 1970s), was an attempt to sort out different areas of language use in multilingual societies, which are relevant for language choice. In Fishman’s version, domains were considered...... not described in terms of domains, and recent research e.g. about the multilingual communities in the Danish-German border area seems to confirm this....

  8. Insertion device vacuum system designs

    International Nuclear Information System (INIS)

    Synchrotron light source insertion device vacuum systems now in operation and systems proposed for the future are reviewed. An overview of insertion devices is given and four generic vacuum chamber designs, transition section design and pumping considerations are discussed. Examples of vacuum chamber systems are presented

  9. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis.

    Science.gov (United States)

    Osman, Gamal H; Assem, Shireen K; Alreedy, Rasha M; El-Ghareeb, Doaa K; Basry, Mahmoud A; Rastogi, Anshu; Kalaji, Hazem M

    2015-01-01

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica. PMID:26658494

  10. Synergistic action of serine- and metallo-proteases from Fusarium oxysporum f. sp. lycopersici cleaves chitin-binding tomato chitinases, reduces their antifungal activity and enhances fungal virulence

    NARCIS (Netherlands)

    Karimi Jashni, M.; Dols, I.; Iida, Y.; Boeren, S.; Beenen, H.G.; Mehrabi, R.; Collemare, J.; Wit, de P.J.G.M.

    2015-01-01

    As part of their defence strategy against fungal pathogens, plants secrete chitinases that degrade chitin, the major structural component of fungal cell walls. Some fungi are not sensitive to plant chitinases because they secrete chitin-binding effector proteins that protect their cell wall against

  11. Optimization of nutrition factors on chitinase production from a newly isolated Chitiolyticbacter meiyuanensis SYBC-H1

    Directory of Open Access Journals (Sweden)

    Zhikui Hao

    2012-03-01

    Full Text Available The present study reports statistical medial optimization for chitinase production by a novel bacterial strain isolated from soil recently, which the name Chitinolyticbacter meiyuanensis SYBC-H1 is proposed. A sequential statistical methodology comprising of Plackett-Burman and response surface methodology (RSM was applied to enhance the fermentative production of chitinase, in which inulin was firstly used as an effective carbon source. As a result, maximum chitinase activity of 5.17 U/mL was obtained in the optimized medium, which was 15.5-fold higher than that in the basal medium. The triplicate verification experiments were performed under the optimized nutrients levels which indicated that it well agreed with the predicted value.

  12. Agrobacterium tumefaciens-mediated transformation of taro (Colocasia esculenta (L.) Schott) with a rice chitinase gene for improved tolerance to a fungal pathogen Sclerotium rolfsii.

    Science.gov (United States)

    He, Xiaoling; Miyasaka, Susan C; Fitch, Maureen M M; Moore, Paul H; Zhu, Yun J

    2008-05-01

    Taro (Colocasia esculenta) is one of the most important crops in the Pacific Islands, however, taro yields have been declining in Hawaii over the past 30 years partly due to diseases caused by oomycete and fungal pathogens. In this study, an efficient Agrobacterium tumefaciens-mediated transformation method for taro is first reported. In total, approximately 200 pieces (8 g) of embryogenic calluses were infected with the super-virulent A. tumefaciens strain EHA105 harboring the plant transformation plasmid pBI121/ricchi11 that contains the rice chitinase gene ricchi11. The presence and expression of the transgene ricchi11 in six independent transgenic lines was confirmed using polymerase chain reaction (PCR) and reverse transcription-PCR (RT-PCR). Southern blot analysis of the six independent lines indicated that three out of six (50%) had integrated a single copy of the transgene, and the other three lines had two or three copies of the transgene. Compared to the particle bombardment transformation of taro method, which was used in the previous studies, the Agrobacterium-mediated transformation method obtained 43-fold higher transformation efficiency. In addition, these six transgenic lines via Agrobacterium may be more effective for transgene expression as a result of single-copy or low-copy insertion of the transgene than the single line with multiple copies of the transgene via particle bombardment. In a laboratory bioassay, all six transgenic lines exhibited increased tolerance to the fungal pathogen Sclerotium rolfsii, ranging from 42 to 63% reduction in lesion expansion.

  13. Cloning of a chitinase gene from Ewingella americana, a pathogen of the cultivated mushroom, Agaricus bisporus

    Directory of Open Access Journals (Sweden)

    P.W. Inglis

    2000-09-01

    Full Text Available We have isolated a gene encoding a chitinase (EC 3.2.1.14 from Ewingella americana, a recently described pathogen of the mushroom Agaricus bisporus. This gene, designated chiA (EMBL/Genbank/DDBJ accession number X90562, was cloned by expression screening of a plasmid-based E. americana HindIII genomic library in Escherichia coli using remazol brilliant violet-stained carboxymethylated chitin incorporated into selective medium. The chiA gene has a 918-bp ORF, terminated by a TAA codon, with a calculated polypeptide size of 33.2 kDa, likely corresponding to a previously purified and characterised 33-kDa endochitinase from E. americana. The deduced amino acid sequence shares 33% identity with chitinase II from Aeromonas sp. No. 10S-24 and 7.8% identity with a chitinase from Saccharopolyspora erythraeus. Homology to other chitinase sequences was otherwise low. The peptide sequence deduced from chiA lacks a typical N-terminal signal sequence and also lacks the chitin binding and type III fibronectin homology units common to many bacterial chitinases. The possibility that this chitinase is not primarily adapted for the environmental mineralisation of pre-formed chitin, but rather for the breakdown of nascent chitin, is discussed in the context of mushroom disease.O gene que codifica uma quitinase (EC 3.2.1.14 foi isolado de Ewingella americana, recentemente descrita como patógeno do cogumelo Agaricus bisporus. Este gene, denominado chiA (EMBL/Genebank/DDBJ número de acesso X9061, foi clonado e selecionado a partir de livraria genômica construída por digestão do DNA de E. americana com HindIII e ligação em plasmídio de expressão em E. coli, utilizando meio seletivo contendo quitina carboximetilada, corada com "remazol brilliant violet'' para seleção de clones. O gene chiA apresenta uma ORF de 918 bp, código terminador TAA, tendo o tamanho do polipeptídeo sido calculado como 33,2 kDa, o qual corresponde ao tamanho de 33 kDa da endoquitinase

  14. Transfer of a plant chitinase gene into a nitrogen-fixing Azospirillum and study of its expression.

    Science.gov (United States)

    Jayaraj, Jayaraman; Muthukrishnan, Subbaratnam; Liang, George H

    2004-07-01

    Azospirillum is used extensively in rice and other cereal crops as a biofertilizer. There is a substantial opportunity to improve the efficiency of this bacterium through the transfer of genes of agricultural importance from other organisms. Chitinases are antifungal proteins, and expression of chitinase genes in Azospirillum would help to develop strains with potential antifungal activities. So far there are no reports about transfer of plant genes into Azospirillum and their expression. The present study was aimed at expressing an antifungal gene (a rice chitinase) of plant origin in Azospirillum brasilense. A rice chitinase cDNA (RC 7) that codes for a 35 kDa protein was subcloned into a broad host range plasmid pDSK519 under the control of LacZ promoter. The plasmid was mobilized into the nitrogen-fixing bacterium, Azospirillum brasilense strain SP51eFL1, through biparental mating. The conjugation frequency was in the range of 35-40 x 10(-6). The transconjugants grew in nitrogen-free media and fixed gaseous nitrogen in vitro. However, their growth and nitrogen-fixing ability were slightly less than those of the wild-type. Expression of the protein was demonstrated through western blotting of the total cell protein, which detected a 35 kDa band that was immuno-reactive to a barley chitinase antibody. The cell lysates also hydrolyzed various chitin substrates, which resulted in release of free sugars demonstrating the chitinase activity of transconjugants. The expressed protein also had antifungal activity as demonstrated by inhibition of growth of the plant pathogenic fungus, Rhizoctonia solani.

  15. G protein signalling involved in host recognition and mycoparasitismrelated chitinase expression in Trichoderma atroviride

    Institute of Scientific and Technical Information of China (English)

    Susanne Zeilinger; Barbara Reithner; Kurt Brunner; Valeria Scala; Isabel Peiβl; Matteo Lorito; Robert L Mach

    2004-01-01

    @@ Mycoparasitic species of Trichoderma are commercially applied as biological control agents against various fungal pathogens. The mycoparasitic interaction is host specific and includes recognition,attack and subsequent penetration and killing of the host. Investigations on the underlying events revealed that Trichoderma responds to multiple signals from the host (e. g. lectins or other ligands such as low molecular weight components released from the host's cell wall) and host attack is accompanied by morphological changes and the secretion of hydrolytic enzymes and antibiotics.Degradation of the cell wall of the host fungus is-besides glucanases and proteases-mainly achieved by chitinases. In vivo studies showed that the ech42 gene (encoding endochitinase 42) is expressed before physical contact of Trichoderma with its host, probably representing one of the earliest events in mycoparasitism, whereas Nag1 (N-acetylglucosaminidase) plays a key role in the general induction of the chitinolytic enzyme system of T. atroviride . Investigations on the responsible signal transduction pathways of T. atroviride led to the isolation of several genes encoding key components of the cAMP and MAP kinase signaling pathways, as alpha and β subunits of heterotrimeric G proteins, the regulatory subunit of cAMP-dependent protein kinase,adenylate cyclase, and three MAP kinases. Analysis of knockout mutants, generated by Agrobacterium-mediated transformation, revealed that at least two alpha-subunits of heterotrimeric G proteins are participating in mycoparasitism-related signal transduction. The Tga1 G alpha subunit was shown to be involved in mycoparasitism-related processes such as chitinase expression and overproduction of toxic secondary metabolites, whereas Tga3 was found to be completely avirulent showing defects in chitinase formation and host recognition.

  16. Bacterial expression of an active class Ib chitinase from Castanea sativa cotyledons.

    Science.gov (United States)

    Allona, I; Collada, C; Casado, R; Paz-Ares, J; Aragoncillo, C

    1996-12-01

    Ch3, an endochitinase of 32 kDa present in Castanea sativa cotyledons, showed in vitro antifungal properties when assayed against Trichoderma viride. The characterization of a cDNA clone corresponding to this protein indicated that Ch3 is a class Ib endochitinase that is synthesized as a preprotein with a signal sequence preceding the mature polypeptide. Bacterial expression of mature Ch3 fused to the leader peptide of the periplasmic protein ompT resulted in active Ch3 enzyme. A plate assay was adapted for semi-quantitative determination of chitinase activity secreted from cultured bacteria, which should facilitate the identification of mutants with altered capacity to hydrolyse chitin.

  17. Molecular cloning, expression and biochemical characterisation of a cold-adapted novel recombinant chitinase from Glaciozyma antarctica PI12

    Directory of Open Access Journals (Sweden)

    Ramli Aizi

    2011-11-01

    Full Text Available Abstract Background Cold-adapted enzymes are proteins produced by psychrophilic organisms that display a high catalytic efficiency at extremely low temperatures. Chitin consists of the insoluble homopolysaccharide β-(1, 4-linked N-acetylglucosamine, which is the second most abundant biopolymer found in nature. Chitinases (EC 3.2.1.14 play an important role in chitin recycling in nature. Biodegradation of chitin by the action of cold-adapted chitinases offers significant advantages in industrial applications such as the treatment of chitin-rich waste at low temperatures, the biocontrol of phytopathogens in cold environments and the biocontrol of microbial spoilage of refrigerated food. Results A gene encoding a cold-adapted chitinase (CHI II from Glaciozyma antarctica PI12 was isolated using Rapid Amplification of cDNA Ends (RACE and RT-PCR techniques. The isolated gene was successfully expressed in the Pichia pastoris expression system. Analysis of the nucleotide sequence revealed the presence of an open reading frame of 1,215 bp, which encodes a 404 amino acid protein. The recombinant chitinase was secreted into the medium when induced with 1% methanol in BMMY medium at 25°C. The purified recombinant chitinase exhibited two bands, corresponding to the non-glycosylated and glycosylated proteins, by SDS-PAGE with molecular masses of approximately 39 and 50 kDa, respectively. The enzyme displayed an acidic pH characteristic with an optimum pH at 4.0 and an optimum temperature at 15°C. The enzyme was stable between pH 3.0-4.5 and was able to retain its activity from 5 to 25°C. The presence of K+, Mn2+ and Co2+ ions increased the enzyme activity up to 20%. Analysis of the insoluble substrates showed that the purified recombinant chitinase had a strong affinity towards colloidal chitin and little effect on glycol chitosan. CHI II recombinant chitinase exhibited higher Vmax and Kcat values toward colloidal chitin than other substrates at low

  18. Expression, purification, crystallization and preliminary crystallographic analysis of chitinase A from Vibrio carchariae

    International Nuclear Information System (INIS)

    Chitinase A of Vibrio carchariae was functionally expressed in Escherichia coli M15 host cells as a C-terminally proteolytic processed fragment using the pQE60 expression vector. The yield of the 63-kDa protein was purified, yielding ∼70 mg per liter of bacterial culture. Crystals of recombinant chitinase A were obtained by the hanging-drop vapor diffusion method in a precipitant containing 10% (v/v) PEG 400, 0.1 M sodium acetate p H 4.6 and 0.125 M CaCl2. The crystals belonged to the tetragonal space group P422 with two molecules per asymmetric unit and unit-cell parameters a = b 127.64 Angstrom, and c = 171.42 Angstrom. A complete diffraction data set was collected to 2.14 Angstrom resolution, using a Rigaku/MSC R-AXIS IV++ detector system mounted on an RU-H3R rotating-anode X-ray generator

  19. Agrobacterium mediated transformation of brassica juncea (l.) czern with chitinase gene conferring resistance against fungal infections

    International Nuclear Information System (INIS)

    Brassica juncea (Czern and Coss., L.) is an important oilseed crop. Since it is attacked by several bacterial and fungal diseases, therefore, we developed an easy and simple protocol for the regeneration and transformation of B. juncea variety RAYA ANMOL to give rise to transgenic plants conferring resistance against various fungal diseases. The transformation was carried out using Agrobacterium with Chitinase gene. This gene was isolated from Streptomyces griseus HUT6037. We used two types of explants for transformation i.e. hypocotyls and cotyledons. Only hypocotyls explants showed good results regarding callus initiation. Different hormonal concentrations were applied i.e. BAP 2, 4 and 6 mgL-1 and NAA 0.1, 0.2 and 0.3 mgL-1. However, high transformation efficiency was observed by supplementing the medium with combination of 2 mgL-1 BAP and 0.2 mgL-1 for initiation of callus. Similarly 10 mgL-1 kanamycin and 200 mgL-1 cefotaxime also proved successful for the selection of transformed callus. In order to confirm the presence of transgenic callus Polymerase chain reaction was performed using specific primers for Chitinase gene. (author)

  20. Chitinase 3-like 1 Regulates Cellular and Tissue Responses via IL-13 Receptor α2

    Directory of Open Access Journals (Sweden)

    Chuan Hua He

    2013-08-01

    Full Text Available Members of the 18 glycosyl hydrolase (GH 18 gene family have been conserved over species and time and are dysregulated in inflammatory, infectious, remodeling, and neoplastic disorders. This is particularly striking for the prototypic chitinase-like protein chitinase 3-like 1 (Chi3l1, which plays a critical role in antipathogen responses where it augments bacterial killing while stimulating disease tolerance by controlling cell death, inflammation, and remodeling. However, receptors that mediate the effects of GH 18 moieties have not been defined. Here, we demonstrate that Chi3l1 binds to interleukin-13 receptor α2 (IL-13Rα2 and that Chi3l1, IL-13Rα2, and IL-13 are in a multimeric complex. We also demonstrate that Chi3l1 activates macrophage mitogen-activated protein kinase, protein kinase B/AKT, and Wnt/β-catenin signaling and regulates oxidant injury, apoptosis, pyroptosis, inflammasome activation, antibacterial responses, melanoma metastasis, and TGF-β1 production via IL-13Rα2-dependent mechanisms. Thus, IL-13Rα2 is a GH 18 receptor that plays a critical role in Chi3l1 effector responses.

  1. Domains and domain loss

    DEFF Research Database (Denmark)

    Haberland, Hartmut

    2005-01-01

    politicians and in the media, especially in the discussion whether some languages undergo ‘domain loss’ vis-à-vis powerful international languages like English. An objection that has been raised here is that domains, as originally conceived, are parameters of language choice and not properties of languages...... theoretical constructs that can explain language choice which were supposed to be a more powerful explanatory tool than more obvious (and observable) parameters like topic, place (setting) and interlocutor. In the meantime, at least in Scandinavia, the term ‘domain’ has been taken up in the debate among...

  2. Tentacles of in vitro-grown round-leaf sundew (Drosera rotundifolia L.) show induction of chitinase activity upon mimicking the presence of prey.

    Science.gov (United States)

    Matusíková, Ildikó; Salaj, Ján; Moravcíková, Jana; Mlynárová, Ludmila; Nap, Jan-Peter; Libantová, Jana

    2005-12-01

    Induction of plant-derived chitinases in the leaves of a carnivorous plant was demonstrated using aseptically grown round-leaf sundew (Drosera rotundifolia L.). The presence of insect prey was mimicked by placing the chemical inducers gelatine, salicylic acid and crustacean chitin on leaves. In addition, mechanical stirring of tentacles was performed. Chitinase activity was markedly increased in leaf exudates upon application of notably chitin. Application of gelatine increased the proteolytic activity of leaf exudates, indicating that the reaction of sundew leaves depends on the molecular nature of the inducer applied. In situ hybridization of sundew leaves with a Drosera chitinase probe showed chitinase gene expression in different cell types of non-treated leaves, but not in the secretory cells of the glandular heads. Upon induction, chitinase mRNA was also present in the secretory cells of the sundew leaf. The combined results indicate that chitinase is likely to be involved in the decomposition of insect prey by carnivorous plants. This adds a novel role to the already broad function of chitinases in the plant kingdom and may contribute to our understanding of the molecular mechanisms behind the ecological success of carnivorous plants in nutritionally poor environments. PMID:16049675

  3. Gene Insertion Patterns and Sites

    Science.gov (United States)

    Vain, Philippe; Thole, Vera

    During the past 25 years, the molecular analysis of transgene insertion patterns and sites in plants has greatly contributed to our understanding of the mechanisms underlying transgene integration, expression, and stability in the nuclear genome. Molecular characterization is also an essential step in the safety assessment of genetically modified crops. This chapter describes the standard experimental procedures used to analyze transgene insertion patterns and loci in cereals and grasses transformed using Agrobacterium tumefaciens or direct transfer of DNA. Methods and protocols enabling the determination of the number and configuration of transgenic loci via a combination of inheritance studies, polymerase chain reaction, and Southern analyses are presented. The complete characterization of transgenic inserts in plants is, however, a holistic process relying on a wide variety of experimental approaches. In this chapter, these additional approaches are not detailed but references to relevant bibliographic records are provided.

  4. Oat (Avena sativa) seed extract as an antifungal food preservative through the catalytic activity of a highly abundant class I chitinase.

    Science.gov (United States)

    Sørensen, Hans Peter; Madsen, Lone Søvad; Petersen, Jørgen; Andersen, Jesper Tapdrup; Hansen, Anne Maria; Beck, Hans Christian

    2010-03-01

    Extracts from different higher plants were screened for the ability to inhibit the growth of Penicillium roqueforti, a major contaminating species in industrial food processing. Oat (Avena sativa) seed extracts exhibited a high degree of antifungal activity and could be used directly on rye bread to prevent the formation of P. roqueforti colonies. Proteins in the oat seed extracts were fractionated by column chromatography and proteins in fractions containing antifungal activity were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and database searches. Identified antifungal candidates included thaumatin-like proteins, 1,3-beta-glucanase, permatin precursor, pathogenesis-related protein type 1, and chitinases of class I and II. Class I chitinase could be specifically removed from the extracts and was found to be indispensable for 50% of the P. roqueforti inhibiting activity. The purified class I chitinase has a molecular weight of approximately 34 kDa, optimal chitinase activity at pH 7, and exists as at least two basic isoforms (pI values of 7.6 and 8.0). Partial sequencing of the class I chitinase isoforms by LC-MS/MS revealed a primary structure with high similarity to class I chitinases of wheat (Triticum aestivum), barley (Hordeum vulgare), and rye (Secale cereale). Oat, wheat, barley, and rye seed extracts were compared with respect to the abundance of the class I chitinase and decrease in antifungal activity when class I chitinase is removed. We found that the oat seed class I chitinase is at least ten times more abundant than the wheat, barley, and rye homologs and that oat seed extracts are highly active toward P. roqueforti as opposed to extracts of other cereal seeds.

  5. CRYSTAL-STRUCTURES OF HEVAMINE, A PLANT DEFENSE PROTEIN WITH CHITINASE AND LYSOZYME ACTIVITY, AND ITS COMPLEX WITH AN INHIBITOR

    NARCIS (Netherlands)

    VANSCHELTINGA, ACT; KALK, KH; BEINTEMA, JJ; DIJKSTRA, BW

    1994-01-01

    Background: Hevamine is a member of one of several families of plant chitinases and lysozymes that are important for plant defence against pathogenic bacteria and fungi. The enzyme can hydrolyze the linear polysaccharide chains of chitin and peptidoglycan. A full understanding of the structure/funct

  6. Determination of cDNA and genomic DNA sequences of hevamine, a chitinase from the rubber tree Hevea brasiliensis

    NARCIS (Netherlands)

    Bokma, E; Spiering, M; Chow, KS; Mulder, PPMFA; Subroto, T; Beintema, JJ

    2001-01-01

    Hevamine is a chitinase from the rubber tree Hevea brasiliensis and belongs to the family 18 glycosyl hydrolases. This paper describes the cloning of hevamine DNA and cDNA sequences. Hevamine contains a signal peptide at the N-terminus and a putative vacuolar targeting sequence at the C-terminus whi

  7. Induction by chromium ions of chitinases and polyamines in barley (Hordeum vulgare L.) and rape (Brassica napus L. ssp. oleifera)

    DEFF Research Database (Denmark)

    Jacobsen, S.; Hauschild, M.Z.; Rasmussen, U.

    1992-01-01

    Barley and rape seedlings were grown in hydroponic culture with increasing concentrations of CrO3 (Cr(VI)) or CrCl3 (Cr(III)). The chitinase activity and the concentrations of putrescine, spennidine and spermine were determined in the third leaf of barley seed-lings and in the second leaf of rape...

  8. Chitinase production by Bacillus subtilis ATCC 11774 and its effect on biocontrol of Rhizoctonia diseases of potato.

    Science.gov (United States)

    Saber, Wesam I A; Ghoneem, Khalid M; Al-Askar, Abdulaziz A; Rashad, Younes M; Ali, Abeer A; Rashad, Ehsan M

    2015-12-01

    Stem canker and black scurf of potato, caused by Rhizoctonia solani, can be serious diseases causing an economically significant damage. Biocontrol activity of Bacillus subtilis ATCC 11774 against the Rhizoctonia diseases of potato was investigated in this study. Chitinase enzyme was optimally produced by B. subtilis under batch fermentation conditions similar to those of the potato-growing soil. The maximum chitinase was obtained at initial pH 8 and 30 °C. In vitro, the lytic action of the B. subtilis chitinase was detected releasing 355 μg GlcNAc ml⁻¹ from the cell wall extract of R. solani and suggesting the presence of various chitinase enzymes in the bacterial filtrate. In dual culture test, the antagonistic behavior of B. subtilis resulted in the inhibition of the radial growth of R. solani by 48.1% after 4 days. Moreover, the extracted B. subtilis chitinase reduced the growth of R. solani by 42.3% when incorporated with the PDA plates. Under greenhouse conditions, application of a bacterial suspension of B. subtilis at 109 cell mL⁻¹ significantly reduced the disease incidence of stem canker and black scurf to 22.3 and 30%, respectively. In addition, it significantly improved some biochemical parameters, growth and tubers yield. Our findings indicate two points; firstly, B. subtilis possesses a good biocontrol activity against Rhizoctonia diseases of potato, secondly, the harmonization and suitability of the soil conditions to the growth and activity of B. subtilis guaranteed a high controlling capacity against the target pathogen. PMID:26616375

  9. Concepts for stereoselective acrylate insertion

    KAUST Repository

    Neuwald, Boris

    2013-01-23

    Various phosphinesulfonato ligands and the corresponding palladium complexes [{((PaO)PdMeCl)-μ-M}n] ([{( X1-Cl)-μ-M}n], (PaO) = κ2- P,O-Ar2PC6H4SO2O) with symmetric (Ar = 2-MeOC6H4, 2-CF3C6H4, 2,6-(MeO)2C6H3, 2,6-(iPrO)2C 6H3, 2-(2′,6′-(MeO)2C 6H3)C6H4) and asymmetric substituted phosphorus atoms (Ar1 = 2,6-(MeO)2C6H 3, Ar2 = 2′-(2,6-(MeO)2C 6H3)C6H4; Ar1 = 2,6-(MeO)2C6H3, Ar2 = 2-cHexOC 6H4) were synthesized. Analyses of molecular motions and dynamics by variable temperature NMR studies and line shape analysis were performed for the free ligands and the complexes. The highest barriers of ΔGa = 44-64 kJ/mol were assigned to an aryl rotation process, and the flexibility of the ligand framework was found to be a key obstacle to a more effective stereocontrol. An increase of steric bulk at the aryl substituents raises the motional barriers but diminishes insertion rates and regioselectivity. The stereoselectivity of the first and the second methyl acrylate (MA) insertion into the Pd-Me bond of in situ generated complexes X1 was investigated by NMR and DFT methods. The substitution pattern of the ligand clearly affects the first MA insertion, resulting in a stereoselectivity of up to 6:1 for complexes with an asymmetric substituted phosphorus. In the consecutive insertion, the stereoselectivity is diminished in all cases. DFT analysis of the corresponding insertion transition states revealed that a selectivity for the first insertion with asymmetric (P aO) complexes is diminished in the consecutive insertions due to uncooperatively working enantiomorphic and chain end stereocontrol. From these observations, further concepts are developed. © 2012 American Chemical Society.

  10. Conversion of α-chitin substrates with varying particle size and crystallinity reveals substrate preferences of the chitinases and lytic polysaccharide monooxygenase of Serratia marcescens.

    Science.gov (United States)

    Nakagawa, Yuko S; Eijsink, Vincent G H; Totani, Kazuhide; Vaaje-Kolstad, Gustav

    2013-11-20

    Industrial depolymerization of chitinous biomass generally requires numerous steps and the use of deleterious substances. Enzymatic methods provide an alternative, but fundamental knowledge that could direct potential development of industrial enzyme cocktails is scarce. We have studied the contribution of monocomponent chitinases (ChiA, -B, and -C) and the lytic polysaccharide monooxygenase (LPMO) from Serratia marcescens on depolymerization of α-chitin substrates with varying particle size and crystallinity that were generated using a converge mill. For all chitinases activity was positively correlated to a decline in particle size and crystallinity. Especially ChiC, the only nonprocessive endochitinase from the S. marcescens chitinolytic machinery, benefited from mechanical pretreatment. Combining the chitinases revealed clear synergies for all substrates tested. CBP21, the chitin-active LPMO from S. marcescens, increased solubilization of substrates with high degrees of crystallinity when combined with each of the three chitinases, but this synergy was reduced upon decline in crystallinity.

  11. Transformation Fava Beans by Agrobacterium using Chitinase, Glucanase and CryIA (b genes

    Directory of Open Access Journals (Sweden)

    A.H Gorji

    2014-01-01

    Full Text Available In this study two plasmid vectors that are appropriate for plant transformation were made by preparation of gene cassettes for β-1, 3-glucanase from barley, chitinase from bean and cryIA (b from Bacillus thuringiensis (BT. Each of these genes were cloned under the control of the CaMV35S  promoter and the Nos terminator in pBI121 binary vector. pBI-Chi  and pBI-Glu and recombinant plasmid vectors were constructed via cloning of chitinase , β-1,3- glucanase and cryIA (b genes, respectively, instead of the gus gene in T-DNA region of pBI121 vector. Construction of pBI-ChiGlu recombinant plasmid vector was performed by means of cloning both of the complete chitinase and glucanase gene cassettes in pBI121 vector, with the intention of production synergistic effects against fungal infection.pBI-ChiBt  recombinant plasmid vector containing both of the complete chitinase and Bt gene cassettes was also constructed in order to contemporaneous plants resistance to pest pathogens and fungal in a single transformation event. pBI-ChiGlu and pBI-ChiBt that have been  introduced into the A. tumefaciens strain LBA4404 that was subsequently used for  transformation. Results indicate that embryogenic calli are well appropriate as objective material for Agrobacterium tumefaciens-mediated transformation in Faba bean.Seventeen well established shoots  were transferred to new MLS medium including suitable  antibiotics.Finally six independent transgenic plants were successfully rooted on kanamycin-containing  selection media and then transferred to soil after 20 days .Four plants out of six putative transgenic plants displaied to contain the end part of the chit transgene and nos terminator.The corresponding  piece, 700 bp of the chit gene, was amplified using specific primer.These putative transgenic plants were also be measured for the presence of the bgn13.1 and cryIA (b genes by PCR using specific primers.Two  pieces with expected sizes (1221 bp and 640

  12. 水稻和拟南芥中几丁质酶的分析%Chitinases in Oryza sativa ssp. japonica and Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    许凤华; 范成明; 何月秋

    2007-01-01

    Chitinases (EC3.2.1.14), found in a wide range of organisms, catalyze the hydrolysis of chitin and play a major role in defense mechanisms against fungal pathogens. The alignment and typical domains were analyzed using basic local alignment search tool (BLAST) and simple modular architecture research tool (SMART), respectively. On the basis of the annotations of rice (Oryza sativa L.) and Arabidopsis genomic sequences and using the bio-software SignalP3.0, TMHMM2.0, TargetPl.1, and big-Pi Predictor, 25 out of 37 and 16 out of 24 open reading frames (ORFs) with chitinase activity from rice and Arabidopsis, respectively, were predicted to have signal peptides (SPs), which have an average of 24.8 amino acids at the N-terminal region. Some of the chitinases were secreted extracellularly, whereas some were located in the vacuole. The phylogenic relationship was analyzed with 61 ORFs and 25 known chitinases and they were classified into 6 clusters using Clustal X and MEGA3.1. This classification is not completely consistent when compared with the traditional system that classifies the chitinases into 7 classes. The frequency of distribution of amino acid residues was distinct in different clusters. The contents of alanine, glycine, serine, and leucine were very high in each cluster, whereas the contents of methionine, histidine, tryptophan, and cysteine were lower than 20%. Each cluster had distinct amino acid characteristics. Alanine, valine, leucine, cysteine, serine, and lysine were rich in Clusters Ⅰ to Ⅵ, respectively.%几丁质酶(EC3.2.1.14)是一种降解几丁质的糖苷酶,广泛存在于各种生物体中,并在植物中对病原真菌起重要抗性作用.首先通过BLAST在GenBank中对其同源性进行搜索,用SMART分析其结构.基于水稻和拟南芥的基因组注释,借助4个生物学软件(SignalP3.0,TMHMM2.0,TargetP1.1 and big-Pi Predictor),分析了水稻所有37条和拟南芥所有24条几丁质酶序列,发现有些几丁质酶都分

  13. Structural investigation of a novel N-acetyl glucosamine binding chi-lectin which reveals evolutionary relationship with class III chitinases.

    Science.gov (United States)

    Patil, Dipak N; Datta, Manali; Dev, Aditya; Dhindwal, Sonali; Singh, Nirpendra; Dasauni, Pushpanjali; Kundu, Suman; Sharma, Ashwani K; Tomar, Shailly; Kumar, Pravindra

    2013-01-01

    The glycosyl hydrolase 18 (GH18) family consists of active chitinases as well as chitinase like lectins/proteins (CLPs). The CLPs share significant sequence and structural similarities with active chitinases, however, do not display chitinase activity. Some of these proteins are reported to have specific functions and carbohydrate binding property. In the present study, we report a novel chitinase like lectin (TCLL) from Tamarindus indica. The crystal structures of native TCLL and its complex with N-acetyl glucosamine were determined. Similar to the other CLPs of the GH18 members, TCLL lacks chitinase activity due to mutations of key active site residues. Comparison of TCLL with chitinases and other chitin binding CLPs shows that TCLL has substitution of some chitin binding site residues and more open binding cleft due to major differences in the loop region. Interestingly, the biochemical studies suggest that TCLL is an N-acetyl glucosamine specific chi-lectin, which is further confirmed by the complex structure of TCLL with N-acetyl glucosamine complex. TCLL has two distinct N-acetyl glucosamine binding sites S1 and S2 that contain similar polar residues, although interaction pattern with N-acetyl glucosamine varies extensively among them. Moreover, TCLL structure depicts that how plants utilize existing structural scaffolds ingenuously to attain new functions. To date, this is the first structural investigation of a chi-lectin from plants that explore novel carbohydrate binding sites other than chitin binding groove observed in GH18 family members. Consequently, TCLL structure confers evidence for evolutionary link of lectins with chitinases.

  14. Postharvest application of a novel chitinase cloned from Metschnikowia fructicola and overexpressed in Pichia pastoris to control brown rot of peaches.

    Science.gov (United States)

    Banani, Houda; Spadaro, Davide; Zhang, Dianpeng; Matic, Slavica; Garibaldi, Angelo; Gullino, Maria Lodovica

    2015-04-16

    Metschnikowia fructicola strain AP47 is a yeast antagonist against postharvest pathogens of fruits. The yeast was able to produce chitinase enzymes in the presence of pathogen cell wall. A novel chitinase gene MfChi (GenBank accession number HQ113461) was amplified from the genomic DNA of Metschnikowia fructicola AP47. Sequence analysis showed lack of introns, an open reading frame (ORF) of 1098 bp encoding a 365 amino acid protein with a calculated molecular weight of 40.9 kDa and a predicted pI of 5.27. MfChi was highly induced in Metschnikowia fructicola after interaction with Monilinia fructicola cell wall, suggesting a primary role of MfChi chitinase in the antagonistic activity of the yeast. The MfChi gene overexpressed in the heterologous expression system of Pichia pastoris KM71 and the recombinant chitinase showed high endochitinase activity towards 4-Nitrophenyl β-d-N,N',N″-triacetylchitotriose substrate. The antifungal activity of the recombinant chitinase was investigated against Monilinia fructicola and Monilinia laxa in vitro and on peaches. The chitinase significantly controlled the spore germination and the germ tube length of the tested pathogens in PDB medium and the mycelium diameter in PDA. The enzyme, when applied on peaches cv. Redhaven, successfully reduced brown rot severity. This work shows that the chitinase MfChi could be developed as a postharvest treatment with antimicrobial activity for fruit undergoing a short shelf life, and confirms that P. pastoris KM71 is a suitable microorganism for cost-effective large-scale production of recombinant chitinases. PMID:25632799

  15. Tentacles of in vitro-grown round-leaf sundew (Drosera rotundifolia L.) show induction of chitinase activity upon mimicking the presence of prey

    OpenAIRE

    Matusikova, I.; Salaj, J.; Moravcikova, J.; Mlynarova, L.; Nap, J.P.H.; Libantova, J.

    2005-01-01

    Induction of plant-derived chitinases in the leaves of a carnivorous plant was demonstrated using aseptically grown round-leaf sundew (Drosera rotundifolia L.). The presence of insect prey was mimicked by placing the chemical inducers gelatine, salicylic acid and crustacean chitin on leaves. In addition, mechanical stirring of tentacles was performed. Chitinase activity was markedly increased in leaf exudates upon application of notably chitin. Application of gelatine increased the proteolyti...

  16. The first LHC insertion quadrupole

    CERN Multimedia

    2004-01-01

    An important milestone was reached in December 2003 at the CERN Magnet Assembly Facility. The team from the Accelerator Technology - Magnet and Electrical Systems group, AT-MEL, completed the first special superconducting quadrupole for the LHC insertions which house the experiments and major collider systems. The magnet is 8 metres long and contains two matching quadrupole magnets and an orbit corrector, a dipole magnet, used to correct errors in quadrupole alignment. All were tested in liquid helium and reached the ultimate performance criteria required for the LHC. After insertion in the cryostat, the superconducting magnet will be installed as the Q9 quadrupole in sector 7-8, the first sector of the LHC to be put in place in 2004. Members of the quadrupole team, from the AT-MEL group, gathered around the Q9 quadrupole at its inauguration on 12 December 2003 in building 181.

  17. Insertion device calculations with mathematica

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R. [Stanford Synchrotron Radiation Lab., CA (United States); Lidia, S. [Univ. of California, Davis, CA (United States)

    1995-02-01

    The design of accelerator insertion devices such as wigglers and undulators has usually been aided by numerical modeling on digital computers, using code in high level languages like Fortran. In the present era, there are higher level programming environments like IDL{reg_sign}, MatLab{reg_sign}, and Mathematica{reg_sign} in which these calculations may be performed by writing much less code, and in which standard mathematical techniques are very easily used. The authors present a suite of standard insertion device modeling routines in Mathematica to illustrate the new techniques. These routines include a simple way to generate magnetic fields using blocks of CSEM materials, trajectory solutions from the Lorentz force equations for given magnetic fields, Bessel function calculations of radiation for wigglers and undulators and general radiation calculations for undulators.

  18. Enhancing plant disease suppression by Burkholderia vietnamiensis through chromosomal integration of Bacillus subtilis chitinase gene chi113.

    Science.gov (United States)

    Zhang, Xinjian; Huang, Yujie; Harvey, Paul R; Ren, Yan; Zhang, Guangzhi; Zhou, Hongzi; Yang, Hetong

    2012-02-01

    Burkholderia vietnamiensis P418 is a plant growth-promoting rhizobacteria. A chitinase gene from Bacillus subtilis was cloned and stably integrated into the chromosome of using the transposon delivery vector, pUTkm1. Chitinase activity was detected in recombinant P418-37 but not in wild type P418. Recombinant P418-37 retained the in vitro growth rate, N(2)-fixation and phosphate and potassium-solubilizing characteristics of the wild type. P418-37 significantly (P Bipolaris sorokiniana, Verticillium dahliae and Gaeumannomyces graminis var. tritici compared with P418. In planta disease suppression assays indicated that P418-37 significantly (P < 0.05) enhanced suppression of wheat sheath blight (R. cerealis), cotton Fusarium wilt (F. oxysporium f.sp. vasinfectum) and tomato gray mould (Botrytis cinerea), relative to the wild type.

  19. Complete genome sequence of the fish pathogen Aeromonas veronii TH0426 with potential application in biosynthesis of pullulanase and chitinase.

    Science.gov (United States)

    Kang, Yuanhuan; Pan, Xiaoyi; Xu, Yang; Siddiqui, Shahrood A; Wang, Chunfeng; Shan, Xiaofeng; Qian, Aidong

    2016-06-10

    Aeromonas veronii TH0426 is a pathogen of the farmed yellow catfish Pelteobagrus fulvidraco but shows high-level expression of pullulanase and chitinase. Here, we present its genome sequence, which is the first reported complete genome of fish pathogen in A. veronii to date. Strain TH0426 harbors a single circular 4,923,009bp chromosome with a GC content of 58.25%. There are 4525 genes identified on its genome, including 4244 protein-coding genes, 32 rRNA genes, 120 tRNA genes, a noncoding RNA and 128 pseudo genes. We believe that the genomic information of A. veronii TH0426 would facilitate to reveal its pathogenic mechanism associated with yellow catfish, develop vaccine to decrease economic losses for fish farming, meanwhile explore the potential application in producing pullulanase and chitinase. PMID:27080448

  20. Field errors in hybrid insertion devices

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, R.D. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed.

  1. Field Errors in Hybrid Insertion Devices

    OpenAIRE

    Schlueter, R.D.

    1995-01-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed.

  2. ECDYSTEROID AND CHITINASE FLUCTUATIONS IN THE WESTERN TARNISHED PLANT BUG (Lygus hesperus) PRIOR TO MOLT INDICATE ROLES IN DEVELOPMENT.

    Science.gov (United States)

    Brent, Colin S; Wang, Meixian; Miao, Yun-Gen; Hull, J Joe

    2016-06-01

    Vital physiological processes that drive the insect molt represent areas of interest for the development of alternative control strategies. The western tarnished plant bug (Lygus hesperus Knight) is a pest of numerous agronomic and horticultural crops but the development of novel control approaches is impeded by limited knowledge of the mechanisms regulating its molt. To address this deficiency, we examined the fundamental relationship underlying the hormonal and molecular components of ecdysis. At 27°C L. hesperus exhibits a temporally controlled nymph-adult molt that occurs about 4 days after the final nymph-nymph molt with ecdysteroid levels peaking 2 days prior to the final molt. Application of exogenous ecdysteroids when endogenous levels had decreased disrupted the nymphal-adult molt, with treated animals exhibiting an inability to escape the old exoskeleton and resulting in mortality compared to controls. Using accessible transcriptomic data, we identified 10 chitinase-like sequences (LhCht), eight of which had protein motifs consistent with chitinases. Phylogenetic analyses revealed orthologous relationships to chitinases critical to molting in other insects. RT-PCR based transcript profiling revealed that expression changes to four of the LhChts was coordinated with the molt period and ecdysteroid levels. Collectively, our results support a role for ecdysteroid regulation of the L. hesperus molt and suggest that cuticle clearance is mediated by LhCht orthologs of chitinases that are essential to the molt process. These results provide the initial hormonal and molecular basis for future studies to investigate the specific roles of these components in molting. PMID:27192063

  3. Does 'insertion' work? France's minimum income"

    OpenAIRE

    Whitton, Timothy

    1993-01-01

    International audience France's Revenu Minimum d Insertion (RMI) received the approval of the French Parliament on 1st December1988, and came into effect shortly afterwardsi. In addition to a means test, the RMI is conditional upon signature of a contract (le contrat d'insertion) by which its recipients pledge themselves to take whatever action the RMI authorities recommend in order to re-insert themselves in main-stream society. Insertion is a difficult concept to translate into English. ...

  4. Delayed bowel perforation following suprapubic catheter insertion

    OpenAIRE

    Mehta Ajay; Ahmed Shwan J; Rimington Peter

    2004-01-01

    Abstract Background Complications of suprapubic catheter insertion are rare but can be significant. We describe an unusual complication of a delayed bowel perforation following suprapubic catheter insertion. Case presentation A gentleman presented with features of peritonitis and feculent discharge along a suprapubic catheter two months after insertion of the catheter. Conclusion Bowel perforation is the most feared complication of suprapubic catheter insertion especially in patients with low...

  5. Tetrahedral mesh for needle insertion

    OpenAIRE

    Syvertsen, Rolf Anders

    2007-01-01

    This is a Master’s thesis in how to make a tetrahedral mesh for use in a needle insertion simulator. It also describes how it is possible to make the simulator, and how to improve it to make it as realistic as possible. The medical simulator uses a haptic device, a haptic scene graph and a FEM for realistic soft tissue deformation and interaction. In this project a tetrahedral mesh is created from a polygon model, and then the mesh has been loaded into the HaptX haptic scene graph. The object...

  6. Progress of Researching Chitinase of Gypsy Moth%舞毒蛾几丁质酶的研究进展

    Institute of Scientific and Technical Information of China (English)

    王绥冬; 宋志芳; 张常; 李瑶; 范晓军

    2012-01-01

    The gypsy moth that is a worldwide forestry pests are distributed in China's provinces. Gypsy moth larvae eat the leaves of fi-uit trees, willow trees, which have serious harm to forestry safety. The article was described the hazards of the gypsy moth, Chitinase relevant knowledge and research status of the gypsy moth Chitinase, and expounded the prospect of application of Chitinase to combat gypsy moth.%舞毒蛾是一种世界性林业害虫,在我国各省均有分布。舞毒蛾幼虫主要蚕食果树、柳树等树木的树叶.严重危害林业安全。文章介绍了舞毒蛾的危害、几丁质酶的相关知识及舞毒蛾几丁质酶的研究现状.并对应用几丁质酶防治舞毒蛾的前景进行了论述。

  7. Purification of a thermostable chitinase from Bacillus cereus by chitin affinity and its application in microbial community changes in soil.

    Science.gov (United States)

    Liang, Tzu-Wen; Hsieh, Tung-Yen; Wang, San-Lang

    2014-06-01

    A thermostable chitinase was purified by chitin affinity from the culture supernatant of Bacillus cereus TKU028 with shrimp head powder (SHP) as the sole carbon/nitrogen source. TKU028 chitinase was purified using a one-step affinity adsorbent system, and the molecular mass of TKU028 chitinase (approximately 40 kDa) was then determined using SDS-PAGE. The enzyme was stable for 60 min at temperatures below 60 °C and stable over a broad pH range of 4-9 for 60 min. In addition, the temporal changes of a bacterial community in mangrove river sediment of the Tamsui River with added SHP were also analysed by PCR-denaturing gradient gel electrophoresis to investigate the effects of B. cereus TKU028 on the degradation of SHP. The 6-week incubation sample of SHP and B. cereus TKU028-amended mangrove river sediment displayed the highest amount of biomass, reducing sugar and total sugar, and some variance of bacterial community composition existed in the soils. PMID:24342954

  8. Domain Engineering

    Science.gov (United States)

    Bjørner, Dines

    Before software can be designed we must know its requirements. Before requirements can be expressed we must understand the domain. So it follows, from our dogma, that we must first establish precise descriptions of domains; then, from such descriptions, “derive” at least domain and interface requirements; and from those and machine requirements design the software, or, more generally, the computing systems.

  9. A small RNA controls expression of the chitinase ChiA in Listeria monocytogenes.

    Directory of Open Access Journals (Sweden)

    Jesper S Nielsen

    Full Text Available In recent years, more than 60 small RNAs (sRNAs have been identified in the gram-positive human pathogen Listeria monocytogenes, but their putative roles and mechanisms of action remain largely unknown. The sRNA LhrA was recently shown to be a post-transcriptional regulator of a single gene, lmo0850, which encodes a small protein of unknown function. LhrA controls the translation and degradation of the lmo0850 mRNA by an antisense mechanism, and it depends on the RNA chaperone Hfq for efficient binding to its target. In the present study, we sought to gain more insight into the functional role of LhrA in L. monocytogenes. To this end, we determined the effects of LhrA on global-wide gene expression. We observed that nearly 300 genes in L. monocytogenes are either positively or negatively affected by LhrA. Among these genes, we identified lmo0302 and chiA as direct targets of LhrA, thus establishing LhrA as a multiple target regulator. Lmo0302 encodes a hypothetical protein with no known function, whereas chiA encodes one of two chitinases present in L. monocytogenes. We show here that LhrA acts as a post-transcriptional regulator of lmo0302 and chiA by interfering with ribosome recruitment, and we provide evidence that both LhrA and Hfq act to down-regulate the expression of lmo0302 and chiA. Furthermore, in vitro binding experiments show that Hfq stimulates the base pairing of LhrA to chiA mRNA. Finally, we demonstrate that LhrA has a negative effect on the chitinolytic activity of L. monocytogenes. In marked contrast to this, we found that Hfq has a stimulating effect on the chitinolytic activity, suggesting that Hfq plays multiple roles in the complex regulatory pathways controlling the chitinases of L. monocytogenes.

  10. The Correlation between Chitin and Acidic Mammalian Chitinase in Animal Models of Allergic Asthma

    Directory of Open Access Journals (Sweden)

    Chia-Rui Shen

    2015-11-01

    Full Text Available Asthma is the result of chronic inflammation of the airways which subsequently results in airway hyper-responsiveness and airflow obstruction. It has been shown that an elicited expression of acidic mammalian chitinase (AMCase may be involved in the pathogenesis of asthma. Our recent study has demonstrated that the specific suppression of elevated AMCase leads to reduced eosinophilia and Th2-mediated immune responses in an ovalbumin (OVA-sensitized mouse model of allergic asthma. In the current study, we show that the elicited expression of AMCase in the lung tissues of both ovalbumin- and Der P2-induced allergic asthma mouse models. The effects of allergic mediated molecules on AMCase expression were evaluated by utilizing promoter assay in the lung cells. In fact, the exposure of chitin, a polymerized sugar and the fundamental component of the major allergen mite and several of the inflammatory mediators, showed significant enhancement on AMCase expression. Such obtained results contribute to the basis of developing a promising therapeutic strategy for asthma by silencing AMCase expression.

  11. Functional properties of a chitinase promoter from cabbage (Brassica oleracea var.capitata)

    Institute of Scientific and Technical Information of China (English)

    TANGGUOQING; YONGYANBAI; 等

    1996-01-01

    The 5'-region of the chitinase gene cabch29,derived from Brassica oleracea var.capitata,has been sequenced and analyzed for cis-acting elements important in controlling gene expression in transgenic tobacco plants.Different 5'-deletion fragments were linked to reporter gene β-glucuronidase (GUS) as translational fusions,and the expression of these chimeric genes was analyzed in vegetative organs and tissues.Sequences up to-651 showed some basal GUS activity with nearly equal levels in wounded and intact tissues.The addition of further upstream sequences(-651 to-1284) enhanced expression level,and the expression driven by this fragment was inducible by a factor of two to three-fold by wounding.Histochemical analysis of different tissue from transgenic plants that contain cabch29 promoter-gus fusion gene demonstrated woundinducible and tissue-specific cabch29 promoter activity in plants containing the 1308 base pair fragment.The location of GUS activity appears to be cell-specific,being highest in vascular cells and epidermal cells of stem,leaf and roots.Meanwhile,the temporal and spatial expression of cabch29-GUS fusion gene has been investigated.Among the different vegetative organs,a high level of GUS activity was observed in stem and a moderate one in roots;whereas,wounding stress led to a high level of GUS in stem and moderate one in leaf.

  12. Activity, stability and folding analysis of the chitinase from Entamoeba histolytica.

    Science.gov (United States)

    Muñoz, Patricia L A; Minchaca, Alexis Z; Mares, Rosa E; Ramos, Marco A

    2016-02-01

    Human amebiasis, caused by the parasitic protozoan Entamoeba histolytica, remains as a significant public health issue in developing countries. The life cycle of the parasite compromises two main stages, trophozoite and cyst, linked by two major events: encystation and excystation. Interestingly, the cyst stage has a chitin wall that helps the parasite to withstand harsh environmental conditions. Since the amebic chitinase, EhCHT1, has been recognized as a key player in both encystation and excystation, it is plausible to consider that specific inhibition could arrest the life cycle of the parasite and, thus, stop the infection. However, to selectively target EhCHT1 it is important to recognize its unique biochemical features to have the ability to control its cellular function. Hence, to gain further insights into the structure-function relationship, we conducted an experimental approach to examine the effects of pH, temperature, and denaturant concentration on the enzymatic activity and protein stability. Additionally, dependence on in vivo oxidative folding was further studied using a bacterial model. Our results attest the potential of EhCHT1 as a target for the design and development of new or improved anti-amebic therapeutics. Likewise, the potential of the oxidoreductase EhPDI, involved in oxidative folding of amebic proteins, was also confirmed.

  13. Aspartate embedding depth affects pHLIP's insertion pKa.

    Science.gov (United States)

    Fendos, Justin; Barrera, Francisco N; Engelman, Donald M

    2013-07-01

    We have used the pHlow insertion peptide (pHLIP) family to study the role of aspartate embedding depth in pH-dependent transmembrane peptide insertion. pHLIP binds to the surface of a lipid bilayer as a largely unstructured monomer at neutral pH. When the pH is lowered, pHLIP inserts spontaneously across the membrane as a spanning α-helix. pHLIP insertion is reversible when the pH is adjusted back to a neutral value. One of the critical events facilitating pHLIP insertion is the protonation of aspartates in the spanning domain of the peptide: the negative side chains of these residues convert to uncharged, polar forms, facilitating insertion by altering the hydrophobicity of the spanning domain. To examine this protonation mechanism further, we created pHLIP sequence variants in which the two spanning aspartates (D14 and D25) were moved up or down in the sequence. We hypothesized that the aspartate depth in the inserted state would directly affect the proton affinity of the acidic side chains, altering the pKa of pH-dependent insertion. To this end, we also mutated the arginine at position 11 to determine whether arginine snorkeling modulates the insertion pKa by affecting the aspartate depth. Our results indicate that both types of mutations change the insertion pKa, supporting the idea that the aspartate depth is a participating parameter in determining the pH dependence. We also show that pHLIP's resistance to aggregation can be altered with our mutations, identifying a new criterion for improving the performance of pHLIP in vivo when targeting acidic disease tissues such as cancer and inflammation. PMID:23721379

  14. The Chitinase Activity in Banana Seedling that Induce by Trichoderma spp as Resistance Responce to Fusarium Oxyporum f.sp.cubense

    Directory of Open Access Journals (Sweden)

    - Nurbailis

    2016-06-01

    Full Text Available An experiment was conducted to study the chitinase activities of banana seedling that induced by Trichoderma spp. The experiment consisted of two parts: 1. Testing chitinase activity in banana seedlings induced by Trichodernia spp., Using a factorial in a completely randomized design with two factors: a. types of inducers (biomass, liquid culture and filtrate, b. Isolates of Trichoderma spp. (T. Koningii-S6sh, T. Viride-T1sk, T.harzianum-P4sh and control. with 4 replications. Parameters measured were, the specific activity of the chitinase enzyme were detected in stems, leaves and roots of banana seedlings. 2. Testing of several types of inducers of Trichoderma spp. in inducing resistance in banana seedlings to Foc, together with the study design 1. Parameters measured were: incubation period, the percentage of symptomatic leaves and percentage discoloration of vessels. Result showed that 1. Liquid culture of induser  T. Viride -T1sk and T. koningii-S6sh and biomass of T. koningii-s6sh and T. harzianum-P4sh were effective in increasing  the specific activity of chitinase enzyme on banana seedling. The increase the amount specific activity of chitinase enzyme on banana seedling tissues by liquid culture of T. viride- T1sk 346% and 131,32% by T. koningii could be  suppress fusarium wilt desease on banana seedling. 

  15. PanoInserts: mobile spatial teleconferencing

    OpenAIRE

    Pece, F.; Steptoe, W.; F. Wanner; Julier, S.; Weyrich, T.; Kautz, J.; Steed, A.

    2013-01-01

    We present PanoInserts: a novel teleconferencing system that uses smartphone cameras to create a surround representation of meeting places. We take a static panoramic image of a location into which we insert live videos from smartphones. We use a combination of marker- and image-based tracking to position the video inserts within the panorama, and transmit this representation to a remote viewer. We conduct a user study comparing our system with fully-panoramic video and conventional webcam vi...

  16. Delayed bowel perforation following suprapubic catheter insertion

    Directory of Open Access Journals (Sweden)

    Mehta Ajay

    2004-12-01

    Full Text Available Abstract Background Complications of suprapubic catheter insertion are rare but can be significant. We describe an unusual complication of a delayed bowel perforation following suprapubic catheter insertion. Case presentation A gentleman presented with features of peritonitis and feculent discharge along a suprapubic catheter two months after insertion of the catheter. Conclusion Bowel perforation is the most feared complication of suprapubic catheter insertion especially in patients with lower abdominal scar. The risk may be reduced with the use of ultrasound scan guidance.

  17. Nozzle insert for mixed mode fuel injector

    Science.gov (United States)

    Lawrence, Keith E.

    2006-11-21

    A fuel injector includes a homogenous charge nozzle outlet set and a conventional nozzle outlet set controlled respectively, by first and second needle valve members. The homogeneous charged nozzle outlet set is defined by a nozzle insert that is attached to an injector body, which defines the conventional nozzle outlet set. The nozzle insert is a one piece metallic component with a large diameter segment separated from a small diameter segment by an annular engagement surface. One of the needle valve members is guided on an outer surface of the nozzle insert, and the nozzle insert has an interference fit attachment to the injector body.

  18. Characterization of a novel Salmonella typhimurium chitinase which hydrolyzes chitin, chitooligosaccharides and an N-acetyllactosamine conjugate

    DEFF Research Database (Denmark)

    Larsen, Tanja; Petersen, Bent O.; Storgaard, Birgit Groth;

    2011-01-01

    Salmonella contain genes annotated as chitinases; however, their chitinolytic activities have never been verified. We now demonstrate such an activity for a chitinase assigned to glycoside hydrolase family 18 encoded by the SL0018 (chiA) gene in Salmonella enterica Typhimurium SL1344. A C...... carboxymethyl chitin Remazol Brilliant Violet but does not act on 4-nitrophenyl N-acetyl-ß-D-glucosaminide, peptidoglycan or 4-nitrophenyl ß-D-cellobioside. Enzyme activity was also characterized by directly monitoring product formation using (1)H-nuclear magnetic resonance which showed that chitin is a...

  19. Marginal adaptation of ceramic inserts after cementation

    NARCIS (Netherlands)

    Ozcan, M; Pfeiffer, P; Nergiz, [No Value

    2002-01-01

    The advantage of using ceramic inserts is to prevent major drawbacks of composite resins such as polymerization shrinkage, wear and microleakage. This in vitro study evaluated the marginal adaptation of two approximal ceramic insert systems after cementation to the cavities opened with ultrasonic ti

  20. An Elementary Account of Needle Insertion

    Institute of Scientific and Technical Information of China (English)

    张文兵; 霍则军

    2004-01-01

    @@ Based on the authors' clinical and personal experiences, several pain-inducing factors easily to be ignored by the operators when quick needle insertion is applied, and the authors' first invented slow painless needle insertion method are introduced in the article.

  1. Central Solenoid Insert Technical Specification

    Energy Technology Data Exchange (ETDEWEB)

    Martovetsky, Nicolai N [ORNL; Smirnov, Alexandre [ORNL

    2011-09-01

    The US ITER Project Office (USIPO) is responsible for the ITER central solenoid (CS) contribution to the ITER project. The Central Solenoid Insert (CSI) project will allow ITER validation the appropriate lengths of the conductors to be used in the full-scale CS coils under relevant conditions. The ITER Program plans to build and test a CSI to verify the performance of the CS conductor. The CSI is a one-layer solenoid with an inner diameter of 1.48 m and a height of 4.45 m between electric terminal ends. The coil weight with the terminals is approximately 820 kg without insulation. The major goal of the CSI is to measure the temperature margin of the CS under the ITER direct current (DC) operating conditions, including determining sensitivity to load cycles. Performance of the joints, ramp rate sensitivity, and stability against thermal or electromagnetic disturbances, electrical insulation, losses, and instrumentation are addressed separately and therefore are not major goals in this project. However, losses and joint performance will be tested during the CSI testing campaign. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at the Japan Atomic Energy Agency (JAEA), Naka, Japan. The industrial vendors (the Suppliers) will report to the USIPO (the Company). All approvals to proceed will be issued by the Company, which in some cases, as specified in this document, will also require the approval of the ITER Organization. Responsibilities and obligations will be covered by respective contracts between the USIPO, called Company interchangeably, and the industrial Prime Contractors, called Suppliers. Different stages of work may be performed by more than one Prime Contractor, as described in this specification. Technical requirements of the contract between the Company and the Prime Contractor will be covered by the Fabrication Specifications developed by the Prime Contractor based on this document and approved by

  2. 华山松疱锈病的重寄生真菌(深绿木霉)中几丁质酶基因cDNA片段的克隆%Cloning of cDNA Fragment of Chitinase Gene from the Mycoparasite Trichoderma atroviride on Armandii Pine Blister Rust

    Institute of Scientific and Technical Information of China (English)

    马长乐; 李靖; 陈玉惠; 刘小烛

    2008-01-01

    [Objective] The aim of this study was to isolate chitinase gene from Trichoderma atroviride strain SS003. [Method] With the aeciospore wall of armandii pine blister rust as inducer, chitinase gene was induced to express in Trichoderma atroviride cells. The cDNA fragment of chitinase gene was cloned by RT-PCR approach. [Result] The activity of chitinase induced reached 40.17 μg/10 min; and the specific fragment amplified was 834 bp in length and proved to be the fragment of chitinase gene by sequencing and sequence analysis. [Conclusion] The result showed the feasibility of isolating the full length of chitinase gene and its transformation, and further producing chitinase.

  3. Abundant class III acidic chitinase homologue in tamarind (Tamarindus indica) seed serves as the major storage protein.

    Science.gov (United States)

    Rao, Devavratha H; Gowda, Lalitha R

    2008-03-26

    The phyla Leguminosae contains protease inhibitors, lectins, chitinases, and glycohydrolases as major defense proteins in their seeds. Electrophoretic analysis of the seed proteins of tamarind ( Tamarindus indica L.), an agri-waste material, indicated the unusual presence of two major proteins comparable to overexpression of recombinant proteins. These proteins were identified by amino-terminal analysis to be (1) Kunitz-type trypsin inhibitor and (2) class III endochitinase (34000 Da). These two proteins were purified to apparent homogeneity by a single-step chitin bead affinity chromatography and characterized. The Kunitz inhibitor was specific toward inhibiting trypsin with a stoichiometry of 1:1. The 33000 +/- 1000 Da protein, accounting for >50% of the total seed protein, is an acidic glycoprotein exhibiting a very low endotype hydrolytic activity toward chitin derivatives. SDS-PAGE followed by densitometry of tamarind seed germination indicates the disappearance of the chitinase with the concomitant appearance of a cysteine endopeptidase. On the basis of its abundance, accumulation without any pathogenesis-related stimulus, temporal regulation, amino acid composition, and very low enzyme activity, this 34000 Da protein designated "tamarinin" physiologically serves as the major storage protein.

  4. Targeting chitinase gene of Helicoverpa armigera by host-induced RNA interference confers insect resistance in tobacco and tomato.

    Science.gov (United States)

    Mamta; Reddy, K R K; Rajam, M V

    2016-02-01

    Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a devastating agricultural insect pest with broad spectrum of host range, causing million dollars crop loss annually. Limitations in the present conventional and transgenic approaches have made it crucial to develop sustainable and environmental friendly methods for crop improvement. In the present study, host-induced RNA interference (HI-RNAi) approach was used to develop H. armigera resistant tobacco and tomato plants. Chitinase (HaCHI) gene, critically required for insect molting and metamorphosis was selected as a potential target. Hair-pin RNAi construct was prepared from the conserved off-target free partial HaCHI gene sequence and was used to generate several HaCHI-RNAi tobacco and tomato plants. Northern hybridization confirmed the production of HaCHI gene-specific siRNAs in HaCHI-RNAi tobacco and tomato lines. Continuous feeding on leaves of RNAi lines drastically reduced the target gene transcripts and consequently, affected the overall growth and survival of H. armigera. Various developmental deformities were also manifested in H. armigera larvae after feeding on the leaves of RNAi lines. These results demonstrated the role of chitinase in insect development and potential of HI-RNAi for effective management of H. armigera.

  5. Discovery and identification of candidate genes from the chitinase gene family for Verticillium dahliae resistance in cotton

    Science.gov (United States)

    Xu, Jun; Xu, Xiaoyang; Tian, Liangliang; Wang, Guilin; Zhang, Xueying; Wang, Xinyu; Guo, Wangzhen

    2016-01-01

    Verticillium dahliae, a destructive and soil-borne fungal pathogen, causes massive losses in cotton yields. However, the resistance mechanism to V. dahilae in cotton is still poorly understood. Accumulating evidence indicates that chitinases are crucial hydrolytic enzymes, which attack fungal pathogens by catalyzing the fungal cell wall degradation. As a large gene family, to date, the chitinase genes (Chis) have not been systematically analyzed and effectively utilized in cotton. Here, we identified 47, 49, 92, and 116 Chis from four sequenced cotton species, diploid Gossypium raimondii (D5), G. arboreum (A2), tetraploid G. hirsutum acc. TM-1 (AD1), and G. barbadense acc. 3–79 (AD2), respectively. The orthologous genes were not one-to-one correspondence in the diploid and tetraploid cotton species, implying changes in the number of Chis in different cotton species during the evolution of Gossypium. Phylogenetic classification indicated that these Chis could be classified into six groups, with distinguishable structural characteristics. The expression patterns of Chis indicated their various expressions in different organs and tissues, and in the V. dahliae response. Silencing of Chi23, Chi32, or Chi47 in cotton significantly impaired the resistance to V. dahliae, suggesting these genes might act as positive regulators in disease resistance to V. dahliae. PMID:27354165

  6. Discovery and identification of candidate genes from the chitinase gene family for Verticillium dahliae resistance in cotton.

    Science.gov (United States)

    Xu, Jun; Xu, Xiaoyang; Tian, Liangliang; Wang, Guilin; Zhang, Xueying; Wang, Xinyu; Guo, Wangzhen

    2016-06-29

    Verticillium dahliae, a destructive and soil-borne fungal pathogen, causes massive losses in cotton yields. However, the resistance mechanism to V. dahilae in cotton is still poorly understood. Accumulating evidence indicates that chitinases are crucial hydrolytic enzymes, which attack fungal pathogens by catalyzing the fungal cell wall degradation. As a large gene family, to date, the chitinase genes (Chis) have not been systematically analyzed and effectively utilized in cotton. Here, we identified 47, 49, 92, and 116 Chis from four sequenced cotton species, diploid Gossypium raimondii (D5), G. arboreum (A2), tetraploid G. hirsutum acc. TM-1 (AD1), and G. barbadense acc. 3-79 (AD2), respectively. The orthologous genes were not one-to-one correspondence in the diploid and tetraploid cotton species, implying changes in the number of Chis in different cotton species during the evolution of Gossypium. Phylogenetic classification indicated that these Chis could be classified into six groups, with distinguishable structural characteristics. The expression patterns of Chis indicated their various expressions in different organs and tissues, and in the V. dahliae response. Silencing of Chi23, Chi32, or Chi47 in cotton significantly impaired the resistance to V. dahliae, suggesting these genes might act as positive regulators in disease resistance to V. dahliae.

  7. A new chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica affects Soybean Asian rust (Phakopsora pachyrhizi spore germination

    Directory of Open Access Journals (Sweden)

    Mehta Angela

    2011-02-01

    Full Text Available Abstract Background Asian rust (Phakopsora pachyrhizi is a common disease in Brazilian soybean fields and it is difficult to control. To identify a biochemical candidate with potential to combat this disease, a new chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica (CaclXIP leaves was cloned into the pGAPZα-B vector for expression in Pichia pastoris. Results A cDNA encoding a chitinase-like xylanase inhibitor protein (XIP from coffee (Coffea arabica (CaclXIP, was isolated from leaves. The amino acid sequence predicts a (β/α8 topology common to Class III Chitinases (glycoside hydrolase family 18 proteins; GH18, and shares similarity with other GH18 members, although it lacks the glutamic acid residue essential for catalysis, which is replaced by glutamine. CaclXIP was expressed as a recombinant protein in Pichia pastoris. Enzymatic assay showed that purified recombinant CaclXIP had only residual chitinolytic activity. However, it inhibited xylanases from Acrophialophora nainiana by approx. 60% when present at 12:1 (w/w enzyme:inhibitor ratio. Additionally, CaclXIP at 1.5 μg/μL inhibited the germination of spores of Phakopsora pachyrhizi by 45%. Conclusions Our data suggests that CaclXIP belongs to a class of naturally inactive chitinases that have evolved to act in plant cell defence as xylanase inhibitors. Its role on inhibiting germination of fungal spores makes it an eligible candidate gene for the control of Asian rust.

  8. Tentacles of in vitro-grown round-leaf sundew (Drosera rotundifolia L.) show induction of chitinase activity upon mimicking the presence of prey

    NARCIS (Netherlands)

    Matusikova, I.; Salaj, J.; Moravcikova, J.; Mlynarova, L.; Nap, J.P.H.; Libantova, J.

    2005-01-01

    Induction of plant-derived chitinases in the leaves of a carnivorous plant was demonstrated using aseptically grown round-leaf sundew (Drosera rotundifolia L.). The presence of insect prey was mimicked by placing the chemical inducers gelatine, salicylic acid and crustacean chitin on leaves. In addi

  9. Tentacles of in vitro-grown round-leaf sundew (Drosera rotundifoliaL.) show induction of chitinase activity upon mimicking the presence of prey

    NARCIS (Netherlands)

    Matusikova, [No Value; Salaj, J; Moravcikova, J; Mlynarova, L; Nap, JP; Libantova, J

    2005-01-01

    Induction of plant-derived chitinases in the leaves of a carnivorous plant was demonstrated using aseptically grown round-leaf sundew (Drosera rotundifolia L.). The presence of insect prey was mimicked by placing the chemical inducers gelatine, salicylic acid and crustacean chitin on leaves. In addi

  10. Kinase-domain insert containing receptor gene silencing inhibited proliferation of human lung cancer cell line A549 and enhanced their sensitivity to docetaxel%血管内皮生长因子激酶功能区受体基因沉默抑制肺癌A549细胞增殖并增强其对多西他赛的敏感性

    Institute of Scientific and Technical Information of China (English)

    张秀义

    2015-01-01

    目的:研究沉默血管内皮生长因子激酶功能区受体( kinase-domain insert containing receptor , KDR)基因对人肺癌A549细胞增殖以及对化疗药物多西他赛敏感性的影响。方法设计合成KDR的小干扰RNA( small interfering RNA ,siRNA)序列,Lipofectamine TM 2000转染入A549细胞。通过反转录-聚合酶链反应和Western Blot检测KDR基因沉默后KDR mRNA及蛋白的表达情况,利用流式细胞仪检测A549细胞的周期变化。采用四甲基偶氮唑盐比色法及细胞克隆形成实验观察,沉默KDR基因后A549细胞对多西他赛的敏感性。结果 KDR基因经48 h沉默后,A549细胞的KDR基因和蛋白的表达出现较明显的下降( P<0.05)。A549细胞的周期在G0/G1期阻滞,S期细胞数目减低(P<0.05)。在KDR基因沉默组,A549细胞对多西他赛的敏感性有明显的增强(P<0.05)。结论 KDR-siRNA能够明显沉默A549细胞KDR基因和蛋白的表达,并能抑制A549细胞的增殖,增强其对多西他赛的敏感性。%Objective This study investigated the effect of small interfering RNA-mediated kinase-domain insert containing receptor ( KDR) knock-down on proliferation of human lung cancer cell line A549 and their sensitivity to docetaxel .Methods The small interfering RNA ( siRNA) against KDR was constructed and transfected into A 549 cells with Lipofectamine TM 2000.The expre-ssion of KDR was detected by reverse transcription-polymerase chain reaction and Western Blot . Flow cytometry was used to detect the cell cycle .Sensitivity to docetaxel after transfection were exa-mined by methyl thiazolyl tetrazolium assay and clonogenic assay .Results In A549 cells, the pro-tein and mRNA levels of KDR were decreased significantly after transfection ,and reduction of proli-feration was related to an increase in the fraction of G 0/G1 phase .The sensitivity of A 549 cells to docetaxel was increased significantly after transfection

  11. An Unusual Complication of Suprapubic Catheter Insertion

    Directory of Open Access Journals (Sweden)

    Krishnan Ananthakrishnan

    2006-01-01

    Full Text Available A patient who had a small bowel mesentery perforation following insertion of a suprapubic catheter (SPC is described. He had no bowel complaints immediately following the procedure, but presented 10 weeks later with insidious onset bowel obstruction due to the kink caused by the catheter. This complication occurred despite cystoscopy control and adequate bladder distension prior to the procedure. This isolated case illustrates the fact that regardless of the ease and frequency of SPC insertion, complications do occur.

  12. Quantitative Real-Time PCR Analysis of YKL-40 and Its Comparison with Mammalian Chitinase mRNAs in Normal Human Tissues Using a Single Standard DNA

    Directory of Open Access Journals (Sweden)

    Misa Ohno

    2015-04-01

    Full Text Available YKL-40 (YKL for the first three N-terminal residues of a 40 kDa protein belongs to a group of human chitinase-like proteins (CLPs, which are similar to chitinases but lack chitinolytic activity. YKL-40 mRNA and its protein levels have been reported elevated in multiple disorders including asthma, cystic fibrosis, rheumatoid arthritis and malignant tumors. Here, we quantified the YKL-40 mRNA levels and compared them with chitinases and housekeeping genes in normal human tissues. To establish the quantitative real-time PCR (qPCR system for evaluation of relative YKL-40 mRNA levels, we constructed a human standard DNA molecule by ligating cDNAs of YKL-40, two mammalian chitinases and two housekeeping genes in a one-to-one ratio. We generated cDNAs from various normal human tissues and analyzed the YKL-40 mRNA expression levels using a qPCR system with the standard DNA. We found that YKL-40 mRNA is present widely in human tissues while its expression patterns exhibit clear tissue specificity. Highest YKL-40 mRNA levels were detected in the liver, followed by kidney, trachea and lung. The levels of YKL-40 mRNA in the kidney and liver were more than 100-times higher than those of chitotriosidase mRNA. Our study provides for the first time a comprehensive analysis of the relative expression levels of YKL-40 mRNA versus mammalian chitinases in normal human tissues.

  13. Z-2 Threaded Insert Design and Testing

    Science.gov (United States)

    Ross, Amy; Rhodes, Richard; Jones, Robert J.; Graziosi, David; Ferl, Jinny; Sweeny, Mitch; Scarborough, Stephen

    2016-01-01

    NASA's Z-2 prototype space suit contains several components fabricated from an advanced hybrid composite laminate consisting of IM10 carbon fiber and fiber glass. One requirement was to have removable, replaceable helicoil inserts to which other suit components would be fastened. An approach utilizing bonded in inserts with helicoils inside of them was implemented. During initial assembly, cracking sounds were heard followed by the lifting of one of the blind inserts out of its hole when the screws were torqued. A failure investigation was initiated to understand the mechanism of the failure. Ultimately, it was determined that the pre-tension caused by torqueing the fasteners is a much larger force than induced from the pressure loads of the suit which was not considered in the insert design. Bolt tension is determined by dividing the torque on the screw by a k value multiplied by the thread diameter of the bolt. The k value is a factor that accounts for friction in the system. A common value used for k for a non-lubricated screw is 0.2. The k value can go down by as much as 0.1 if the screw is lubricated which means for the same torque, a much larger tension could be placed on the bolt and insert. This paper summarizes the failure investigation that was performed to identify the root cause of the suit failure and details how the insert design was modified to resist a higher pull out tension.

  14. The Basques according to polymorphic Alu insertions.

    Science.gov (United States)

    de Pancorbo, M M; López-Martínez, M; Martínez-Bouzas, C; Castro, A; Fernández-Fernández, I; de Mayolo, G A; de Mayolo, A A; de Mayolo, P A; Rowold, D J; Herrera, R J

    2001-08-01

    Polymorphic Alu insertions provide a set of DNA markers of interest in human population genetics. Approximately 1000-2000 of these insertions have not reached fixation within the human genome. Each one of these polymorphic loci most probably resulted from a unique insertional event, and therefore all individuals possessing the insertion are related by descent not just state. In addition, the direction of mutational change is toward the gain of the Alu element at a particular locus. Therefore, the improved knowledge of both the ancestral state and the direction of mutational change greatly facilitates the analysis of population relationships. As a result, Alu insertion polymorphisms represent a significant tool for population genetic studies. In this study, polymorphic Alu insertions have been employed to ascertain phylogenetic relationships among Basque groups and worldwide populations. The Basques are considered to be a geographic isolate with a unique language and customs. They may be direct descendants of Cro-Magnon enclaves from the upper Paleolithic (38,000 to 10,000 years). The Basques are distributed among narrow valleys in northeastern Spain with little migration between them until recently. This characteristic may have had an effect on allelic frequency distributions. With the aim of studying this possible effect, we have analyzed six autosomal polymorphic Alu loci from four different sites within the Spanish Basque region in order to ascertain any genetic heterogeneity among the Basques. The results are consistent with a lack of homogeneity among these four autochthonous Basque groups. PMID:11511929

  15. Trusted Domain

    DEFF Research Database (Denmark)

    Hjorth, Theis Solberg; Torbensen, Rune

    2012-01-01

    In the digital age of home automation and with the proliferation of mobile Internet access, the intelligent home and its devices should be accessible at any time from anywhere. There are many challenges such as security, privacy, ease of configuration, incompatible legacy devices, a wealth...... of wireless standards, limited resources of embedded systems, etc. Taking these challenges into account, we present a Trusted Domain home automation platform, which dynamically and securely connects heterogeneous networks of Short-Range Wireless devices via simple non-expert user. interactions, and allows...... that enables secure end-to-end communication with home automation devices, and it supports device revocations as well as a structure of intersecting sets of nodes for scalability. Devices in the Trusted Domain are registered in a list that is distributed using a robust epidemic protocol optimized...

  16. Identification and Antagonism Study of a Novel Chitinase-producing Bacterium Burkholderia Sp.C3 against Phytopathogenic Fungi

    Institute of Scientific and Technical Information of China (English)

    金虹; TAO Yong

    2006-01-01

    Through a modified agar well diffusion assay, antagonism of a novel chitinase-producing strain C3 against the phytopathogenic fungi including Phoma wasabiae Yokogi,Heterostrophus, Exserohilum Turcicum, Curwularia (Walk) Boed, Thantephorus cucumris, Fusarium graminearum was tested. The data showed that the crude cxtracts of strain C3 had stable antifungal activity in the range of pH 5.0 to pH 8.0. The active components were heat labile and sensitive to proteinase K. A series of experiments supported that the compound responsible for inhibitory activity appeared to be ehitinase. The 16s rDNA analysis indicated that C3 was subject to genus Burkholderia. Pbenotypic characterization of C3 was also consisted with the result of molecular identification.

  17. Regulation of amylase, cellulase and chitinase secretion in the digestive tract of the two-spotted field cricket, Gryllus bimaculatus.

    Science.gov (United States)

    Weidlich, Sandy; Müller, Sonja; Hoffmann, Klaus H; Woodring, Joseph

    2013-06-01

    The secretion of amylase and cellulase in Gryllus bimaculatus is determined by increased food intake, whereby shortly after molting food consumption increases. About half of the standing amylase concentration (activity) in the endothelial cells can be secreted within 30 min. The peak of amylase and cellulase secretion that occurs in the photophase is related to the feeding peak in the previous scotophase. The secretion of chitinase on the other hand is primarily controlled by the molting cycle. Only amylase secretion was affected by calcium in the incubation medium, suggesting an apocrine release mechanism. Refeeding experiments (after 5 days without food) suggest that the release of amylase in response to a nutrient in the lumen (glucose) is not due to simple stimulation of exocytosis, but rather a stimulation of synthesis. PMID:23585293

  18. Hamstring tendons insertion - an anatomical study

    Directory of Open Access Journals (Sweden)

    Cristiano Antonio Grassi

    2013-09-01

    Full Text Available OBJECTIVE: To study the anatomy of the hamstring tendons insertion and anatomical rela-tionships. METHODS: Ten cadaver knees with medial and anterior intact structures were selected. The dissection was performed from anteromedial access to exposure of the insertion of the flexor tendons (FT, tibial plateau (TP and tibial tuberosity (TT. A needle of 40 × 12 and a caliper were used to measure the distance of the tibial plateau of the knee flexor tendons insertion at 15 mm from the medial border of the patellar tendon and tibial tuberosity to the insertion of the flexor tendons of the knee. The angle between tibial plateau and the insertion of the flexor tendons of the knee (A-TP-FT was calculated using Image Pro Plus software. RESULTS: The mean distance TP-FT was 41 ± 4.6 mm. The distance between the TT-FT was 6.88 ± 1 mm. The (A-TP-FT was 20.3 ± 4.9°. CONCLUSION: In the anterior tibial flexor tendons are about 40 mm from the plateau with an average of 20°.

  19. MD-simulations of Beta-Amyloid Protein Insertion Efficiency and Kinetics into Neuronal Membrane Mimics

    Science.gov (United States)

    Qiu, Liming; Buie, Creighton; Vaughn, Mark; Cheng, Kwan

    2011-03-01

    Early interaction events of beta-amyloid (A β) peptides with the neuronal membranes play a key role in the pathogenesis of Alzheimer's disease. We have used all-atom MD simulations to study the protein insertion efficiency and kinetics of monomeric A β40 and A β42 into phosphatidylcholine lipid bilayers (PC) with and without 40 mole% cholesterol (CHOL) that mimic the cholesterol-enriched and depleted lipid nanodomains of the neuronal plasma membranes. Independent replicates of 200-ns simulations of each protein pre-inserted in the upper lipid layer were generated. In PC bilayers, only 25% of A β40 and 50% of A β42 in the replicates showed complete insertion into the lower lipid layer, whereas the percentages increased to 50% and 100%, respectively, in PC/CHOL bilayers, providing evidence that cholesterol improves the protein insertion efficiency into the bilayers. The rate of protein insertion was proportional to the hydrophobic, transmembrane helix length of the inserted peptide and depended on the cholesterol content. We propose that the lysine snorkeling and C-terminus anchoring of A β to the PC headgroups at the upper and lower lipid/water interfaces represent the dual-transmembrane stabilization mechanisms of A β in the neuronal membrane domains.

  20. The chitinase-like protein YKL-40 increases mucin5AC production in human bronchial epithelial cells

    International Nuclear Information System (INIS)

    Mucus overproduction is an important feature in patients with chronic inflammatory airway diseases. However, the regulatory mechanisms that mediate excessive mucin production remain elusive. Recently, the level of YKL-40, a chitinase-like protein, has been found to be significantly increased in chronic inflammatory airway diseases and has been shown to be associated with the severity of these diseases. In this study, we sought to explore the effect of YKL-40 on mucin5AC (MUC5AC) production in chronic inflammatory airway diseases and the potential signaling pathways involved in this process. We found that elevated YKL-40 levels increased the mRNA and protein expression of MUC5AC in a dose- and time-dependent manner, in association with the phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB), reflecting their activation. These responses were significantly suppressed by the knockdown of protease-activating receptor 2 (PAR2) with specific small interfering RNA or the inhibitors of ERK and NF-κB. YKL-40-induced MUC5AC overproduction was also effectively attenuated by the inhibitor of focal adhesion kinase (FAK). Taken together, these results imply that YKL-40 can stimulate excessive MUC5AC production through PAR2- and FAK-mediated mechanisms. - Highlights: • MUC5AC is the major secreted mucin in chronic inflammatory airway diseases. • YKL-40 is a prototype of the chitinase-like protein in mammals. • YKL-40 is an active player in chronic inflammatory airway diseases. • YKL-40 can increase MUC5AC production via PAR2-mediated pathway. • FAK is another candidate to mediate YKL-40-induced MUC5AC overexpression

  1. Transgenic Indian Cotton (Gossypium hirsutum Harboring Rice Chitinase Gene (Chi II Confers Resistance to Two Fungal Pathogens

    Directory of Open Access Journals (Sweden)

    M. Ganesan

    2009-01-01

    Full Text Available Problem statement: The present investigation described a simple and reproducible protocol for transgenic cotton regeneration and characterization of chitinase (Chi II gene expression against two different fungal pathogens in cotton. Approach: Transgenic cotton (Gossypium hirsutum cv. SVPR2 plants were produced by pCambia-bar-Chi II (13.8 kb under the control of the CaMV 35S promoter, harbored in the strain LBA 4404 Agrobacterium tumefaciens by using shoot tip explants. Results: Finally, from the 10 experiments, 21.8% of transformation frequency was recorded. Segregation ratio of 3:1 was recorded in the T0 plant seeds. Polymerase chain reaction and southern blotting analysis were used to confirm the integration of Chi II transgene in the T0 plants genome of putative transgenics. Quantitiave and qualitative (SDS-PAGE analyses were also carried out to confirm the expression of chitinase enzyme in T0 plants. Further, randomly selected transgenic plants (T0 were analyzed for disease tolerance by evaluating them with spores of Fusarium oxysporum and Alternaria macrospora. All the selected PCR positive plants showed enhanced disease resistance against Fusarium wilt. The plants selected randomly showed an enhanced survival rate compared with the control when they were grown in earthen pots inoculated with 1×105 spores 100-1 g of soil mixture. Another four randomly selected plantlets were sprayed with spores of Alternaria macrospora in order to test their tolerance to Alternaria leaf spot disease. After 20 days of culture, the number of lesions per leaf and the lesion length per leaf spot in non-transferred leaves increased. In the case of transgenic plantlets, lesion formation was completely absent. Conclusion: The disease resistance against Fusarium wilt and Alternaria leaf spot in cotton strains would serve as good breeding materials for producing fungal disease resistant cotton varieties.

  2. Evaluation of kinetic parameters of chitinases produced by Beauveria bassiana (Bals.) Vuill. /
    Avaliação de parâmetros cinéticos de quitinases produzidas por Beauveria bassiana (Bals.) Vuill.

    OpenAIRE

    Cristiane Mita; Vanessa Hitomi Sugahara; Jo I Wu; Pedro Manoel Oliveira Janeiro Neves; Dalva Tomoe Miyagui; Geni Varéa-Pereira; Danieli Cristina Sassá; Evelyn Kamogawa

    2008-01-01

    Entomopathogenic fungus Beauveria bassiana is currently used as a biocontrol agent for agricultural pests. The infection process involves extracellular enzymes such as proteases and chitinases that degrade the cuticle of the insects. The objective of this work was to evaluate kinetic parameters of pH, temperature, ionic concentration and time of reaction on chitinases activity. The fungus B. bassiana CG432 was cultivated on coffee berry borer Hypothenemus hampei (Ferrari) and the conidia grow...

  3. HaSNPV几丁质酶的分离纯化与毒理学研究%Purification and Toxicological Studies of HaSNPV Chitinase

    Institute of Scientific and Technical Information of China (English)

    惠有为; 夏天; 赵亚玲; 贾静芳

    2011-01-01

    Recombinant bacterium GS115-pPIC 9k-ChiA 4.0 fermented chitinase, which was purified by ammomum sulfate precipitation, dialysis , DEAE Sepharose Fast Flow ion exchange chromatography and Sephadex G-1OO gel filtration chromatography, obtained electrophoretically pure chitinase. Rate of recovery was 19. 64% , and purification factor was 17. 74. Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus ( HaSNPV) chitinase toxicological studies carried out by contact toxicity and stomach toxicity, chitinase liquefied Plutella xylostella larvae cell and caused death. The effect and the concentration of chitinase is proportional to time, and the effect caused by stomach toxicity was more intense than by action of contact toxicity. The result of antibacterial experiments which were performed on Helminthosporium sativum , Tomato botrytis cinerea , Tobacco brown spot , and Colletotrichum gloeosporioides , indicated that chitinase can inhibit fungal by enzymatic hydrolysis of chitin in fungal cell wall.%利用重组工程茵GSl 15-pPIC 9k-ChiA 4.0发酵几丁质酶粗液,经(NH4)2SO4盐析、透析、DEAE SepIlarose Fast F1ow离子交换层析以及Sephadex G-100凝胶过滤层析分离纯化,获得电泳纯的棉铃虫单粒包埋型核型多角体病毒(HasNPV)几丁质酶,回收率为19.64%,纯化17.74倍;经HaSNPV几丁质酶毒理学研究,通过触杀作用和胃毒作用,几丁质酶使小菜蛾幼虫细胞液化,导致死亡,其作用效果与几丁质酶浓度和作用时间成正比,且胃毒作用大于触杀作用;经小麦根腐、烟草赤星、番茄灰霉和苹果炭疽等植物病原真菌的抑菌实验,表明几丁质酶可以通过酶解真菌细胞壁中的几丁质达到抑茵作用.

  4. True anteroposterior view pedicle screw insertion technique

    Directory of Open Access Journals (Sweden)

    Bai JY

    2016-06-01

    Full Text Available Jia-yue Bai, Wei Zhang, Ji-long An, Ya-peng Sun, Wen-yuan Ding, Yong Shen Key Biomechanical Laboratory of Orthopedics, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China Background: The wide use of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF surgery in the treatment of degenerative disc disease of lumbar spine in spinal surgery highlights the gradual decrease in the use of traditional pedicle screw insertion technology. This study aims to analyze the accuracy of the true anteroposterior view pedicle screw insertion technique in MIS-TLIF surgery, compare it with conventional pedicle screw insertion technology, and discuss its clinical application value. Methods: Fifty-two patients undergoing true anteroposterior view (group A and 87 patients undergoing conventional pedicle screw insertion (group B were diagnosed with lumbar disc herniation or lumbar spinal stenosis. Time for screw placement, intraoperative irradiation exposure, accuracy rate of pedicle screw insertion, and incidence of neurovascular injury were compared between the two groups. Results: The time for screw placement and intraoperative irradiation exposure was significantly less in group A. Penetration rates of the paries lateralis of vertebral pedicle, medial wall of vertebral pedicle, and anterior vertebral wall were 1.44%, 0%, and 2.40%, respectively, all of which were significantly lower than that in group B. No additional serious complications caused by the placement of screw were observed during the follow-up period in patients in group A, but two patients with medial penetration underwent revision for unbearable radicular pain. Conclusion: The application of true anteroposterior view pedicle screw insertion technique in MIS-TLIF surgery shortens time for screw placement and reduces the intraoperative irradiation exposure along with a higher accuracy rate of screw placement, which makes it a safe, accurate

  5. RERTR-12 Insertion 2 Irradiation Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    D. M. Perez; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  6. Allosteric Switching by Mutually Exclusive Folding of Protein Domains

    OpenAIRE

    Radley, Tracy L.; Markowska, Anna I.; Bettinger, Blaine T.; Ha, Jeung-Hoi; Loh, Stewart N.

    2003-01-01

    Many proteins are built from structurally and functionally distinct and domains. A major goal is to understand how conformational change transmits information between domains in order to achieve biological activity. A two-domain, bi-functional fusion protein has been designed so that the mechanical stress imposed by the folded structure of one subunit causes the other subunit to unfold, and vice versa. The construct consists of ubiquitin inserted into a surface loop of barnase. The distance b...

  7. Frequency, Gradience, and Variation in Consonant Insertion

    Science.gov (United States)

    An, Young-ran

    2010-01-01

    This dissertation addresses the extent to which linguistic behavior can be described in terms of the projection of patterns from existing lexical items, through an investigation of Korean reduplication. Korean has a productive pattern of reduplication in which a consonant is inserted in a vowel-initial base, illustrated by forms such as "alok"--"t…

  8. Thermal Performance of the XRS Helium Insert

    Science.gov (United States)

    Breon, Susan R.; DiPirro, Michael J.; Tuttle, James G.; Shirron, Peter J.; Warner, Brent A.; Boyle, Robert F.; Canavan, Edgar R.

    1999-01-01

    The X-Ray Spectrometer (XRS) is an instrument on the Japanese Astro-E satellite, scheduled for launch early in the year 2000. The XRS Helium Insert comprises a superfluid helium cryostat, an Adiabatic Demagnetization Refrigerator (ADR), and the XRS calorimeters with their cold electronics. The calorimeters are capable of detecting X-rays over the energy range 0.1 to 10 keV with a resolution of 12 eV. The Helium Insert completed its performance and verification testing at Goddard in January 1999. It was shipped to Japan, where it has been integrated with the neon dewar built by Sumitomo Heavy Industries. The Helium Insert was given a challenging lifetime requirement of 2.0 years with a goal of 2.5 years. Based on the results of the thermal performance tests, the predicted on-orbit lifetime is 2.6 years with a margin of 30%. This is the result of both higher efficiency in the ADR cycle and the low temperature top-off, more than compensating for an increase in the parasitic heat load. This paper presents a summary of the key design features and the results of the thermal testing of the XRS Helium Insert.

  9. Digital Image Watermarking With Random Selection of Watermark Insertion Having Adaptive Strength

    Directory of Open Access Journals (Sweden)

    G.S. Kalra

    2014-02-01

    Full Text Available We have presented an algorithm of digital image watermarking for gray scale images which we implemented in frequency domain. Before inserting the watermark, we added the Hamming codes row wise as well column wise. Two encryption techniques were implemented on the ECC inserted watermark for its security. The pixel position for inserting the watermark was calculated using starting row and column number for that 8×8 block. Pixel embedding strength is calculated using criteria that low frequency is robust in general signal processing attacks, thus choosing less value to be embedded and vice-versa. Results show that the watermarking algorithm is robust against common signal processing attacks. The algorithm is tested against multiple attacks also.

  10. Penicillium ochrochloron MTCC 517 chitinase: An effective tool in commercial enzyme cocktail for production and regeneration of protoplasts from various fungi.

    Science.gov (United States)

    Patil, Nilambari S; Jadhav, Jyoti P

    2015-03-01

    Penicillium ochrochloron MTCC 517 is a potent producer of chitinolytic enzymes. Novozyme 234, traditional enzyme cocktail for protoplast generation is not available in the market. So, new enzyme cocktail is prepared for protoplast formation from various filamentous fungi which consists of 5 mg ml(-1) lysing enzymes from Trichoderma harzianum, 0.06 mg ml(-1) β-glucuronidase from Helix pomatia and 1 mg ml(-1) P. ochrochloron chitinase. The greatest number of protoplasts could be produced from most of the fungi in 0.8 M sorbitol and by incubation for about 2 h at 37 °C, but the number was decreased by incubation for more than 3 h. About twice as many protoplasts were produced from different species of fungi by involvement of P. ochrochloron chitinase than with combined commercial enzymes. PMID:25737658

  11. Structural and Histone Binding Ability Characterizations of Human PWWP Domains

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hong; Zeng, Hong; Lam, Robert; Tempel, Wolfram; Amaya, Maria F.; Xu, Chao; Dombrovski, Ludmila; Qiu, Wei; Wang, Yanming; Min, Jinrong (Toronto); (Penn)

    2013-09-25

    The PWWP domain was first identified as a structural motif of 100-130 amino acids in the WHSC1 protein and predicted to be a protein-protein interaction domain. It belongs to the Tudor domain 'Royal Family', which consists of Tudor, chromodomain, MBT and PWWP domains. While Tudor, chromodomain and MBT domains have long been known to bind methylated histones, PWWP was shown to exhibit histone binding ability only until recently. The PWWP domain has been shown to be a DNA binding domain, but sequence analysis and previous structural studies show that the PWWP domain exhibits significant similarity to other 'Royal Family' members, implying that the PWWP domain has the potential to bind histones. In order to further explore the function of the PWWP domain, we used the protein family approach to determine the crystal structures of the PWWP domains from seven different human proteins. Our fluorescence polarization binding studies show that PWWP domains have weak histone binding ability, which is also confirmed by our NMR titration experiments. Furthermore, we determined the crystal structures of the BRPF1 PWWP domain in complex with H3K36me3, and HDGF2 PWWP domain in complex with H3K79me3 and H4K20me3. PWWP proteins constitute a new family of methyl lysine histone binders. The PWWP domain consists of three motifs: a canonical {beta}-barrel core, an insertion motif between the second and third {beta}-strands and a C-terminal {alpha}-helix bundle. Both the canonical {beta}-barrel core and the insertion motif are directly involved in histone binding. The PWWP domain has been previously shown to be a DNA binding domain. Therefore, the PWWP domain exhibits dual functions: binding both DNA and methyllysine histones.

  12. Turnabout Is Fair Play: Herbivory-Induced Plant Chitinases Excreted in Fall Armyworm Frass Suppress Herbivore Defenses in Maize1[OPEN

    Science.gov (United States)

    Alves, Patrick C.M.S.; Gaffoor, Iffa; Acevedo, Flor E.; Peiffer, Michelle; Jin, Shan; Han, Yang; Shakeel, Samina; Felton, Gary W.

    2016-01-01

    The perception of herbivory by plants is known to be triggered by the deposition of insect-derived factors such as saliva and oral secretions, oviposition materials, and even feces. Such insect-derived materials harbor chemical cues that may elicit herbivore and/or pathogen-induced defenses in plants. Several insect-derived molecules that trigger herbivore-induced defenses in plants are known; however, insect-derived molecules suppressing them are largely unknown. In this study, we identified two plant chitinases from fall armyworm (Spodoptera frugiperda) larval frass that suppress herbivore defenses while simultaneously inducing pathogen defenses in maize (Zea mays). Fall armyworm larvae feed in enclosed whorls of maize plants, where frass accumulates over extended periods of time in close proximity to damaged leaf tissue. Our study shows that maize chitinases, Pr4 and Endochitinase A, are induced during herbivory and subsequently deposited on the host with the feces. These plant chitinases mediate the suppression of herbivore-induced defenses, thereby increasing the performance of the insect on the host. Pr4 and Endochitinase A also trigger the antagonistic pathogen defense pathway in maize and suppress fungal pathogen growth on maize leaves. Frass-induced suppression of herbivore defenses by deposition of the plant-derived chitinases Pr4 and Endochitinase A is a unique way an insect can co-opt the plant’s defense proteins for its own benefit. It is also a phenomenon unlike the induction of herbivore defenses by insect oral secretions in most host-herbivore systems. PMID:26979328

  13. Extraction of Crude Chitinase from Higher Plants and their Chitin-Hydrolysis Activities; Kotosyokubutu yurai kichinaze no chusyutu to kichin bunkai kassei

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, K.; Harada, K.; Shibata, M.; Maeda, R. [Doshisha Univ., Kyoto (Japan). Faculty of Engineering

    1997-07-10

    To prepare a purified chitinase from higher plants, firstly, crude enzymes were extracted from six higher plants, namely, radish seeds, sunflower seeds, watermelon seeds, bamboo leaves, orange skin, and persimmon skin. Using these crude enzymes, pH dependencies of hydrolysis reaction of colloidal chitin are investigated. For radish seeds and bamboo leaves, which have relatively high activities, the kinetics of enzymatic reaction are studies. It is clear that these reactions obey Michaelis-Menten kinetics. 7 refs., 3 figs., 2 tabs.

  14. Wide-range antifungal antagonism of Paenibacillus ehimensis IB-X-b and its dependence on chitinase and beta-1,3-glucanase production.

    Science.gov (United States)

    Aktuganov, G; Melentjev, A; Galimzianova, N; Khalikova, E; Korpela, T; Susi, P

    2008-07-01

    Previously, we isolated a strain of Bacillus that had antifungal activity and produced lytic enzymes with fungicidal potential. In the present study, we identified the bacterium as Paenibacillus ehimensis and further explored its antifungal properties. In liquid co-cultivation assays, P. ehimensis IB-X-b decreased biomass production of several pathogenic fungi by 45%-75%. The inhibition was accompanied by degradation of fungal cell walls and alterations in hyphal morphology. Residual medium from cultures of P. ehimensis IB-X-b inhibited fungal growth, indicating the inhibitors were secreted into the medium. Of the 2 major lytic enzymes, chitinases were only induced by chitin-containing substrates, whereas beta-1,3-glucanase showed steady levels in all carbon sources. Both purified chitinase and beta-1,3-glucanase degraded cell walls of macerated fungal mycelia, whereas only the latter also degraded cell walls of intact mycelia. The results indicate synergism between the antifungal action mechanisms of these enzymes in which beta-1,3-glucanase is the initiator of the cell wall hydrolysis, whereas the degradation process is reinforced by chitinases. Paenibacillus ehimensis IB-X-b has pronounced antifungal activity with a wide range of fungi and has potential as a biological control agent against plant pathogenic fungi.

  15. Interaction of nuclease colicins with membranes: insertion depth correlates with bilayer perturbation.

    Directory of Open Access Journals (Sweden)

    Mireille Vankemmelbeke

    Full Text Available BACKGROUND: Protein transport across cellular membranes is an important aspect of toxin biology. Escherichia coli cell killing by nuclease colicins occurs through DNA (DNases or RNA (RNases hydrolysis and to this end their cytotoxic domains require transportation across two sets of membranes. In order to begin to unravel the molecular mechanisms underlying the membrane translocation of colicin nuclease domains, we have analysed the membrane association of four DNase domains (E9, a charge reduction E9 mutant, E8, and E7 and one ribosomal RNase domain (E3 using a biomembrane model system. PRINCIPAL RESULTS: We demonstrate, through the use of large unilamellar vesicles composed of synthetic and E. coli lipids and a membrane surface potential sensor, that the colicin nuclease domains bind anionic membranes only, with micromolar affinity and via a cooperative binding mechanism. The evaluation of the nuclease bilayer insertion depth, through a fluorescence quenching analysis using brominated lipids, indicates that the nucleases locate to differential regions in the bilayer. Colicin DNases target the interfacial region of the lipid bilayer, with the DNase E7 showing the deepest insertion, whereas the ribosomal RNase E3 penetrates into the hydrophobic core region of the bilayer. Furthermore, the membrane association of the DNase E7 and the ribosomal RNase E3 induces vesicle aggregation, lipid mixing and content leakage to a much larger extent than that of the other DNases analysed. CONCLUSIONS/SIGNIFICANCE: Our results show, for the first time, that after the initial electrostatically driven membrane association, the pleiotropic membrane effects induced by colicin nuclease domains relate to their bilayer insertion depth and may be linked to their in vivo membrane translocation.

  16. Comparison of conventional Injection Mould Inserts to Additively Manufactured Inserts using Life Cycle Assessment

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael;

    2016-01-01

    Polymer Additive Manufacturing can be used to produce soft tooling inserts for injection moulding. Compared to conventional tooling, the energy and time consumption during production are significantly lower. As the life time of such inserts is significantly shorter than the life time of traditional...... of their potential environmental impact and yield throughout the development and pilot phase. Insert geometry is particularly advantageous for pilot production and small production sizes. In this research, Life Cycle Assessment is used to compare the environmental impact of soft tooling by Additive Manufacturing...... (using Digital Light Processing) and three traditional methods for the manufacture of inserts (milling of brass, steel, and aluminium) for injection moulds during the pre-production phase....

  17. 一种简便易行的几丁质酶纯化法%A Simple and Convenient Method in the Process of Chitinase Purification

    Institute of Scientific and Technical Information of China (English)

    张新军; 岳海梅; 张伏军; 范丽卿

    2011-01-01

    传统的纯化微生物产几丁质酶的方法步骤繁琐、不易控制、得率较低。经过实验探索得出一种较简单、快速、并可批量处理的几丁质酶纯化法。将含有几丁质酶的发酵上清液与胶体几丁质混合后离心,几丁质酶随胶体几丁质沉降而与其他成分分离,用蒸馏水洗涤沉淀,再用蒸馏水重悬,放入30℃恒温箱温育72h,胶体几丁质被完全水解,从而得到纯几丁质酶。此纯化方法条件温和,可保证纯化后的酶保持其生物活性。SDS—PAGE检测及比色法对其纯度检测表明几丁质酶纯化回收率达到88.53%。%Traditional purification of chitinase from the fermentation supernatant had some weaknesses such as complicated steps, difficult in controlling and low recovery ratio. Then we took experimental exploration and find a simple,fast and convenient method in the process of chitinase purification. This method may also be used in Batch processing. Detailed method is: fermentation supernatant which containing chitinase was first mixed with colloidal chitin, after centrifugation, the chitinase and the colloidal chitin precipitated and separated with other components in the supernatant. Then the precipitated was washed by distilled water for several times, the precipitate was then resuspended in distilled water and then sterilized at 30 ℃ for 72h. After the colloidal chitin was completely hydrolyzed, chitin enzyme was purified and abstracted. This method requires simple, mild purification conditions, ensuring the purified enzyme maintain its biological activity. SDS - PAGE and colorimetry detecting methods indicated that the recovery rate of chitinase using this method can reach 88.53%.

  18. Involvement of the MAPK and PI3K pathways in chitinase 3-like 1-regulated hyperoxia-induced airway epithelial cell death

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Na; Lee, Kyung Eun; Hong, Jung Yeon; Heo, Won Il; Kim, Kyung Won; Kim, Kyu Earn [Department of Pediatrics and Institute of Allergy, Severance Medical Research Institute, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul (Korea, Republic of); Sohn, Myung Hyun, E-mail: mhsohn@yuhs.ac [Department of Pediatrics and Institute of Allergy, Severance Medical Research Institute, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2012-05-18

    Highlights: Black-Right-Pointing-Pointer Hyperoxia induces apoptosis and chitinase 3-like 1 expression in human airway epithelial cells. Black-Right-Pointing-Pointer Presence of chitinase 3-like 1 affects airway epithelial cell death after hyperoxic exposure. Black-Right-Pointing-Pointer Silencing chitinase 3-like 1 manipulate the phosphorylation of ERK, p38 and Akt. -- Abstract: Background: Exposure to 100% oxygen causes hyperoxic acute lung injury characterized by cell death and injury of alveolar epithelial cells. Recently, the role of chitinase 3-like 1 (CHI3L1), a member of the glycosyl hydrolase 18 family that lacks chitinase activity, in oxidative stress was demonstrated in murine models. High levels of serum CHI3L1 have been associated with various diseases of the lung, such as asthma, chronic obstructive pulmonary disease, and cancer. However, the role of CHI3L1 in human airway epithelial cells undergoing oxidative stress remains unknown. In addition, the signaling pathways associated with CHI3L1 in this process are poorly understood. Purpose: In this study, we demonstrate the role of CHI3L1, along with the MAPK and PI3K signaling pathways, in hyperoxia-exposed airway epithelial cells. Method: The human airway epithelial cell line, BEAS-2B, was exposed to >95% oxygen (hyperoxia) for up to 72 h. Hyperoxia-induced cell death was determined by assessing cell viability, Annexin-V FITC staining, caspase-3 and -7 expression, and electron microscopy. CHI3L1 knockdown and overexpression studies were conducted in BEAS-2B cells to examine the role of CHI3L1 in hyperoxia-induced apoptosis. Activation of the MAPK and PI3K pathways was also investigated to determine the role of these signaling cascades in this process. Results: Hyperoxia exposure increased CHI3L1 expression and apoptosis in a time-dependent manner. CHI3L1 knockdown protected cells from hyperoxia-induced apoptosis. In contrast, CHI3L1 overexpression promoted cell death after hyperoxia exposure. Finally

  19. Roles for retrotransposon insertions in human disease.

    Science.gov (United States)

    Hancks, Dustin C; Kazazian, Haig H

    2016-01-01

    Over evolutionary time, the dynamic nature of a genome is driven, in part, by the activity of transposable elements (TE) such as retrotransposons. On a shorter time scale it has been established that new TE insertions can result in single-gene disease in an individual. In humans, the non-LTR retrotransposon Long INterspersed Element-1 (LINE-1 or L1) is the only active autonomous TE. In addition to mobilizing its own RNA to new genomic locations via a "copy-and-paste" mechanism, LINE-1 is able to retrotranspose other RNAs including Alu, SVA, and occasionally cellular RNAs. To date in humans, 124 LINE-1-mediated insertions which result in genetic diseases have been reported. Disease causing LINE-1 insertions have provided a wealth of insight and the foundation for valuable tools to study these genomic parasites. In this review, we provide an overview of LINE-1 biology followed by highlights from new reports of LINE-1-mediated genetic disease in humans. PMID:27158268

  20. Beamline Insertions Manager at Jefferson Lab

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Michael C. [Jefferson Lab., Newport News, VA (United States)

    2015-09-01

    The beam viewer system at Jefferson Lab provides operators and beam physicists with qualitative and quantitative information on the transverse electron beam properties. There are over 140 beam viewers installed on the 12 GeV CEBAF accelerator. This paper describes an upgrade consisting of replacing the EPICS-based system tasked with managing all viewers with a mixed system utilizing EPICS and high-level software. Most devices, particularly the beam viewers, cannot be safely inserted into the beam line during high-current beam operations. Software is partly responsible for protecting the machine from untimely insertions. The multiplicity of beam-blocking and beam-vulnerable devices motivates us to try a data-driven approach. The beamline insertions application components are centrally managed and configured through an object-oriented software framework created for this purpose. A rules-based engine tracks the configuration and status of every device, along with the beam status of the machine segment containing the device. The application uses this information to decide on which device actions are allowed at any given time.

  1. [Historical evolution of package inserts in Brazil].

    Science.gov (United States)

    Caldeira, Telma Rodrigues; Neves, Eugênio Rodrigo Zimmer; Perini, Edson

    2008-04-01

    In Brazil, package inserts provide key information on pharmaceuticals. The current study analyzes the evolution of package inserts and the impact on this process by scientific research and development, globalization of information, and various health policies. The study began with a retrospective review of Brazilian health legislation until 1920, the year when the National Public Health Department was created. The analysis of documents on the evolution of health regulation in Brazil began with the Brazilian Pharmaceutical Collection-Health Rulings. The second stage of the study involved a search of standards and norms in VISALEGIS: Health Surveillance Legislation, Portal for Legislation from the National Congressional Information System and the Health Legislation System. Package inserts became an important vehicle for information in the country and underwent important regulatory changes in the latter half of the 20th century. From 1946 to 2006, the number of mandatory items increased, with more in-depth description. However, the standardization of information for medicines with the same active ingredient failed to materialize, despite its importance and the various legal initiatives in this direction.

  2. Optimization of ITER Central Solenoid Insert design

    Energy Technology Data Exchange (ETDEWEB)

    Khodak, Andrei, E-mail: akhodak@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Martovetsky, Nicolai; Smirnov, Alexandre [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Titus, Peter [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States)

    2013-10-15

    Highlights: ► Modifications of coil design for testing ITER superconducting cable are presented. ► Numerical analysis allowed optimal selection of the material for the coil spacers. ► Current sharing temperature distributions along the cable are predicted. -- Abstract: The United States ITER Project Office (USIPO) is responsible for fabrication of the Central Solenoid (CS) for International Thermonuclear Experimental Reactor (ITER). The CS Insert (CSI) project should provide a verification of the conductor performance in relevant conditions of temperature, field, currents and mechanical strain. The US IPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at JAEA, Naka. One of the design goals of the CSI is to assure that the properties of the conductor near the median plane are measured accurately. Since Nb3Sn is strain sensitive and electromagnetic forces generate a significant strain that increases the current sharing temperature (T{sub cs}), we need to design the Insert in such a way that the most strained conductor near the median plane would still have the lowest T{sub cs} of all the rest of the conductor in the Insert. The difference between thermal contraction of the jacket and spacer material allows controlling axial distribution of the coil radial deformation. Numerical analysis of the CSI was performed using stainless steel, titanium and invar spacer material variants. Distribution of the T{sub cs} was obtained from numerical results in the form similar to one proposed for ITER.

  3. App-assisted external ventricular drain insertion.

    Science.gov (United States)

    Eftekhar, Behzad

    2016-09-01

    The freehand technique for insertion of an external ventricular drain (EVD) is based on fixed anatomical landmarks and does not take individual variations into consideration. A patient-tailored approach based on augmented-reality techniques using devices such as smartphones can address this shortcoming. The Sina neurosurgical assist (Sina) is an Android mobile device application (app) that was designed and developed to be used as a simple intraoperative neurosurgical planning aid. It overlaps the patient's images from previously performed CT or MRI studies on the image seen through the device camera. The device is held by an assistant who aligns the images and provides information about the relative position of the target and EVD to the surgeon who is performing EVD insertion. This app can be used to provide guidance and continuous monitoring during EVD placement. The author describes the technique of Sina-assisted EVD insertion into the frontal horn of the lateral ventricle and reports on its clinical application in 5 cases as well as the results of ex vivo studies of ease of use and precision. The technique has potential for further development and use with other augmented-reality devices. PMID:26654178

  4. Flavonoid Interaction with a Chitinase from Grape Berry Skin: Protein Identification and Modulation of the Enzymatic Activity

    Directory of Open Access Journals (Sweden)

    Antonio Filippi

    2016-09-01

    Full Text Available In the present study, an antibody raised against a peptide sequence of rat bilitranslocase (anti-peptide Ab was tested on microsomal proteins obtained from red grape berry skin. Previously, this antibody had demonstrated to recognize plant membrane proteins associated with flavonoid binding and transport. Immuno-proteomic assays identified a number of proteins reacting with this particular antibody, suggesting that the flavonoid binding and interaction may be extended not only to carriers of these molecules, but also to enzymes with very different functions. One of these proteins is a pathogenesis-related (PR class IV chitinase, whose in vitro chitinolytic activity was modulated by two of the most representative flavonoids of grape, quercetin and catechin, as assessed by both spectrophotometric and fluorimetric assays in grape microsomes and commercial enzyme preparations. The effect of these flavonoids on the catalysis and its kinetic parameters was also evaluated, evidencing that they determine a hormetic dose-dependent response. These results highlight the importance of flavonoids not only as antioxidants or antimicrobial effectors, but also as modulators of plant growth and stress response. Implications of the present suggestion are here discussed in the light of environment and pesticide-reduction concerns.

  5. CytR Is a Global Positive Regulator of Competence, Type VI Secretion, and Chitinases in Vibrio cholerae.

    Science.gov (United States)

    Watve, Samit S; Thomas, Jacob; Hammer, Brian K

    2015-01-01

    The facultative pathogen Vibrio cholerae transitions between its human host and aquatic reservoirs where it colonizes chitinous surfaces. Growth on chitin induces expression of chitin utilization genes, genes involved in DNA uptake by natural transformation, and a type VI secretion system that allows contact-dependent killing of neighboring bacteria. We have previously shown that the transcription factor CytR, thought to primarily regulate the pyrimidine nucleoside scavenging response, is required for natural competence in V. cholerae. Through high-throughput RNA sequencing (RNA-seq), we show that CytR positively regulates the majority of competence genes, the three type VI secretion operons, and the four known or predicted chitinases. We used transcriptional reporters and phenotypic analysis to determine the individual contributions of quorum sensing, which is controlled by the transcription factors HapR and QstR; chitin utilization that is mediated by TfoX; and pyrimidine starvation that is orchestrated by CytR, toward each of these processes. We find that in V. cholerae, CytR is a global regulator of multiple behaviors affecting fitness and adaptability in the environment.

  6. A small RNA controls expression of the chitinase ChiA in Listeria monocytogenes

    DEFF Research Database (Denmark)

    Nielsen, Jesper S; Larsen, Marianne Halberg; Lillebæk, Eva Maria Sternkopf;

    2011-01-01

    In recent years, more than 60 small RNAs (sRNAs) have been identified in the gram-positive human pathogen Listeria monocytogenes, but their putative roles and mechanisms of action remain largely unknown. The sRNA LhrA was recently shown to be a post-transcriptional regulator of a single gene, lmo...... role of LhrA in L. monocytogenes. To this end, we determined the effects of LhrA on global-wide gene expression. We observed that nearly 300 genes in L. monocytogenes are either positively or negatively affected by LhrA. Among these genes, we identified lmo0302 and chiA as direct targets of LhrA, thus...... establishing LhrA as a multiple target regulator. Lmo0302 encodes a hypothetical protein with no known function, whereas chiA encodes one of two chitinases present in L. monocytogenes. We show here that LhrA acts as a post-transcriptional regulator of lmo0302 and chiA by interfering with ribosome recruitment...

  7. Effect of mouse antisera targeting the Phlebotomus papatasi midgut chitinase PpChit1 on sandfly physiology and fitness

    Directory of Open Access Journals (Sweden)

    Maricela Robles-Murguia

    2014-12-01

    Full Text Available In sandflies, the absence of the peritrophic matrix (PM affects the rate of blood digestion. Also, the kinetics of PM secretion varies according to species. We previously characterised PpChit1, a midgut-specific chitinase secreted in Phlebotomus papatasi (PPIS that is involved in the maturation of the PM and showed that antibodies against PpChit1 reduce the chitinolytic activity in the midgut of several sandfly species. Here, sandflies were fed on red blood cells reconstituted with naïve or anti-PpChit1 sera and assessed for fitness parameters that included blood digestion, oviposition onset, number of eggs laid, egg bouts, average number of eggs per bout and survival. In PPIS, anti-PpChit1 led to a one-day delay in the onset of egg laying, with flies surviving three days longer compared to the control group. Anti-PpChit1 also had a negative effect on overall ability of flies to lay eggs, as several gravid females from all three species were unable to lay any eggs despite having lived longer than control flies. Whereas the longer survival might be associated with improved haeme scavenging ability by the PM, the inability of females to lay eggs is possibly linked to changes in PM permeability affecting nutrient absorption.

  8. Mining of unexplored habitats for novel chitinases--chiA as a helper gene proxy in metagenomics.

    Science.gov (United States)

    Cretoiu, Mariana Silvia; Kielak, Anna Maria; Abu Al-Soud, Waleed; Sørensen, Søren J; van Elsas, Jan Dirk

    2012-06-01

    The main objective of this study was to assess the abundance and diversity of chitin-degrading microbial communities in ten terrestrial and aquatic habitats in order to provide guidance to the subsequent exploration of such environments for novel chitinolytic enzymes. A combined protocol which encompassed (1) classical overall enzymatic assays, (2) chiA gene abundance measurement by qPCR, (3) chiA gene pyrosequencing, and (4) chiA gene-based PCR-DGGE was used. The chiA gene pyrosequencing is unprecedented, as it is the first massive parallel sequencing of this gene. The data obtained showed the existence across habitats of core bacterial communities responsible for chitin assimilation irrespective of ecosystem origin. Conversely, there were habitat-specific differences. In addition, a suite of sequences were obtained that are as yet unregistered in the chitinase database. In terms of chiA gene abundance and diversity, typical low-abundance/diversity versus high-abundance/diversity habitats was distinguished. From the combined data, we selected chitin-amended agricultural soil, the rhizosphere of the Arctic plant Oxyria digyna and the freshwater sponge Ephydatia fluviatilis as the most promising habitats for subsequent bioexploration. Thus, the screening strategy used is proposed as a guide for further metagenomics-based exploration of the selected habitats. PMID:22526805

  9. Potentiation of the synergistic activities of chitinases ChiA, ChiB and ChiC from Serratia marcescens CFFSUR-B2 by chitobiase (Chb) and chitin binding protein (CBP).

    Science.gov (United States)

    Gutiérrez-Román, Martha Ingrid; Dunn, Michael F; Tinoco-Valencia, Raunel; Holguín-Meléndez, Francisco; Huerta-Palacios, Graciela; Guillén-Navarro, Karina

    2014-01-01

    With the goal of understanding the chitinolytic mechanism of the potential biological control strain Serratia marcescens CFFSUR-B2, genes encoding chitinases ChiA, ChiB and ChiC, chitobiase (Chb) and chitin binding protein (CBP) were cloned, the protein products overexpressed in Escherichia coli as 6His-Sumo fusion proteins and purified by affinity chromatography. Following affinity tag removal, the chitinolytic activity of the recombinant proteins was evaluated individually and in combination using colloidal chitin as substrate. ChiB and ChiC were highly active while ChiA was inactive. Reactions containing both ChiB and ChiC showed significantly increased N-acetylglucosamine trimer and dimer formation, but decreased monomer formation, compared to reactions with either enzyme alone. This suggests that while both ChiB and ChiC have a general affinity for the same substrate, they attack different sites and together degrade chitin more efficiently than either enzyme separately. Chb and CBP in combination with ChiB and ChiC (individually or together) increased their chitinase activity. We report for the first time the potentiating effect of Chb on the activity of the chitinases and the synergistic activity of a mixture of all five proteins (the three chitinases, Chb and CBP). These results contribute to our understanding of the mechanism of action of the chitinases produced by strain CFFSUR-B2 and provide a molecular basis for its high potential as a biocontrol agent against fungal pathogens.

  10. Predicting detection performance with model observers: Fourier domain or spatial domain?

    Science.gov (United States)

    Chen, Baiyu; Yu, Lifeng; Leng, Shuai; Kofler, James; Favazza, Christopher; Vrieze, Thomas; McCollough, Cynthia

    2016-03-01

    The use of Fourier domain model observer is challenged by iterative reconstruction (IR), because IR algorithms are nonlinear and IR images have noise texture different from that of FBP. A modified Fourier domain model observer, which incorporates nonlinear noise and resolution properties, has been proposed for IR and needs to be validated with human detection performance. On the other hand, the spatial domain model observer is theoretically applicable to IR, but more computationally intensive than the Fourier domain method. The purpose of this study is to compare the modified Fourier domain model observer to the spatial domain model observer with both FBP and IR images, using human detection performance as the gold standard. A phantom with inserts of various low contrast levels and sizes was repeatedly scanned 100 times on a third-generation, dual-source CT scanner at 5 dose levels and reconstructed using FBP and IR algorithms. The human detection performance of the inserts was measured via a 2-alternative-forced-choice (2AFC) test. In addition, two model observer performances were calculated, including a Fourier domain non-prewhitening model observer and a spatial domain channelized Hotelling observer. The performance of these two mode observers was compared in terms of how well they correlated with human observer performance. Our results demonstrated that the spatial domain model observer correlated well with human observers across various dose levels, object contrast levels, and object sizes. The Fourier domain observer correlated well with human observers using FBP images, but overestimated the detection performance using IR images.

  11. New cardiac retractor for epicardial electrode insertion via subxiphoid approach.

    Science.gov (United States)

    Sakamoto, T; Arai, H; Suzuki, A

    1993-04-01

    A new retractor for the insertion of epicardial screw-in electrodes is described. We have found that this instrument can be easily applied to the heart and gives excellent exposure for electrode insertion.

  12. Roles for retrotransposon insertions in human disease

    OpenAIRE

    Dustin C Hancks; Kazazian, Haig H.

    2016-01-01

    Over evolutionary time, the dynamic nature of a genome is driven, in part, by the activity of transposable elements (TE) such as retrotransposons. On a shorter time scale it has been established that new TE insertions can result in single-gene disease in an individual. In humans, the non-LTR retrotransposon Long INterspersed Element-1 (LINE-1 or L1) is the only active autonomous TE. In addition to mobilizing its own RNA to new genomic locations via a “copy-and-paste” mechanism, LINE-1 is able...

  13. Compiler-assisted static checkpoint insertion

    Science.gov (United States)

    Long, Junsheng; Fuchs, W. K.; Abraham, Jacob A.

    1992-01-01

    This paper describes a compiler-assisted approach for static checkpoint insertion. Instead of fixing the checkpoint location before program execution, a compiler enhanced polling mechanism is utilized to maintain both the desired checkpoint intervals and reproducible checkpoint 1ocations. The technique has been implemented in a GNU CC compiler for Sun 3 and Sun 4 (Sparc) processors. Experiments demonstrate that the approach provides for stable checkpoint intervals and reproducible checkpoint placements with performance overhead comparable to a previously presented compiler assisted dynamic scheme (CATCH) utilizing the system clock.

  14. Penetration of a Single Domain of Bacillus thuringiensis Cry1Ie-Domain I to a Lipid Membrane In vitro

    Institute of Scientific and Technical Information of China (English)

    GUO Shu-yuan; LI Jie; CHEN Zhen; HE Kang-lai

    2014-01-01

    Domain I of the activated Crystal protein from Bacillus thuringiensis has a sevenα-helix bundle structure, which is responsible for membrane channel formation in its insecticidal mechanism. Cry1Ie is toxic to Asian corn borer, Ostrinia furnacalis (Guenée), and plays important roles in insect biological control. The domain I from Cry1Ie has been expressed and puriifed in its normal conformation, as embedded in the full length homologous toxin structure. The membrane insertion ability of this single domain was compared with the full length homologous toxin using a monolayer insertion experiment. The results indicated that the Cry1Ie-domain I had the ability to insert into the lipid monolayer, and this ability is greater than that of the IE648 toxin. However, the state of insertion is not stable and remains for only a short period of time. The Cry1Ie-domain I plays no role in receptor binding as it had a nonspeciifc binding with the brush border membrane vesicles of the Asian corn borer.

  15. Insertion and deletion processes in recent human history.

    Directory of Open Access Journals (Sweden)

    Per Sjödin

    Full Text Available BACKGROUND: Although insertions and deletions (indels account for a sizable portion of genetic changes within and among species, they have received little attention because they are difficult to type, are alignment dependent and their underlying mutational process is poorly understood. A fundamental question in this respect is whether insertions and deletions are governed by similar or different processes and, if so, what these differences are. METHODOLOGY/PRINCIPAL FINDINGS: We use published resequencing data from Seattle SNPs and NIEHS human polymorphism databases to construct a genomewide data set of short polymorphic insertions and deletions in the human genome (n = 6228. We contrast these patterns of polymorphism with insertions and deletions fixed in the same regions since the divergence of human and chimpanzee (n = 10,546. The macaque genome is used to resolve all indels into insertions and deletions. We find that the ratio of deletions to insertions is greater within humans than between human and chimpanzee. Deletions segregate at lower frequency in humans, providing evidence for deletions being under stronger purifying selection than insertions. The insertion and deletion rates correlate with several genomic features and we find evidence that both insertions and deletions are associated with point mutations. Finally, we find no evidence for a direct effect of the local recombination rate on the insertion and deletion rate. CONCLUSIONS/SIGNIFICANCE: Our data strongly suggest that deletions are more deleterious than insertions but that insertions and deletions are otherwise generally governed by the same genomic factors.

  16. T-tube insertion for sclerotic subglottic stenosis.

    Science.gov (United States)

    Goto, Taichiro; Kato, Ryoichi

    2014-02-01

    T-tube insertion is effective treatment for subglottic stenosis, but it is generally difficult due to bending of the T-tube. In a 52-year-old woman with relapsing polychondritis, a T-tube was inserted after predilatation using Hegar dilators. We describe the details of our T-tube insertion methods for sclerotic subglottic stenosis.

  17. Construction of small-insert and large-insert metagenomic libraries.

    Science.gov (United States)

    Simon, Carola; Daniel, Rolf

    2010-01-01

    The vast majority of the Earth's biological diversity is hidden in uncultured and yet uncharacterized microbial genomes. The construction of metagenomic libraries is a cultivation-independent molecular approach to assess this unexplored genetic reservoir. In the last few years, a high number of novel biocatalysts have been identified by function-based or sequence-based screening of metagenomic libraries. Here, we describe detailed protocols for the construction of metagenomic small-insert and large-insert libraries in plasmids and fosmids, respectively, from environmental DNA. PMID:20830554

  18. Polymeric Biodegradable Stent Insertion in the Esophagus

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2016-04-01

    Full Text Available Esophageal stent insertion has been used as a well-accepted and effective alternative to manage and improve the quality of life for patients diagnosed with esophageal diseases and disorders. Current stents are either permanent or temporary and are fabricated from either metal or plastic. The partially covered self-expanding metal stent (SEMS has a firm anchoring effect and prevent stent migration, however, the hyperplastic tissue reaction cause stent restenosis and make it difficult to remove. A fully covered SEMS and self-expanding plastic stent (SEPS reduced reactive hyperplasia but has a high migration rate. The main advantage that polymeric biodegradable stents (BDSs have over metal or plastic stents is that removal is not require and reduce the need for repeated stent insertion. But the slightly lower radial force of BDS may be its main shortcoming and a post-implant problem. Thus, strengthening support of BDS is a content of the research in the future. BDSs are often temporarily effective in esophageal stricture to relieve dysphagia. In the future, it can be expect that biodegradable drug-eluting stents (DES will be available to treat benign esophageal stricture, perforations or leaks with additional use as palliative modalities for treating malignant esophageal stricture, as the bridge to surgery or to maintain luminal patency during neoadjuvant chemoradiation.

  19. Membrane and Protein Interactions of the Pleckstrin Homology Domain Superfamily.

    Science.gov (United States)

    Lenoir, Marc; Kufareva, Irina; Abagyan, Ruben; Overduin, Michael

    2015-01-01

    The human genome encodes about 285 proteins that contain at least one annotated pleckstrin homology (PH) domain. As the first phosphoinositide binding module domain to be discovered, the PH domain recruits diverse protein architectures to cellular membranes. PH domains constitute one of the largest protein superfamilies, and have diverged to regulate many different signaling proteins and modules such as Dbl homology (DH) and Tec homology (TH) domains. The ligands of approximately 70 PH domains have been validated by binding assays and complexed structures, allowing meaningful extrapolation across the entire superfamily. Here the Membrane Optimal Docking Area (MODA) program is used at a genome-wide level to identify all membrane docking PH structures and map their lipid-binding determinants. In addition to the linear sequence motifs which are employed for phosphoinositide recognition, the three dimensional structural features that allow peripheral membrane domains to approach and insert into the bilayer are pinpointed and can be predicted ab initio. The analysis shows that conserved structural surfaces distinguish which PH domains associate with membrane from those that do not. Moreover, the results indicate that lipid-binding PH domains can be classified into different functional subgroups based on the type of membrane insertion elements they project towards the bilayer. PMID:26512702

  20. Membrane and Protein Interactions of the Pleckstrin Homology Domain Superfamily.

    Science.gov (United States)

    Lenoir, Marc; Kufareva, Irina; Abagyan, Ruben; Overduin, Michael

    2015-01-01

    The human genome encodes about 285 proteins that contain at least one annotated pleckstrin homology (PH) domain. As the first phosphoinositide binding module domain to be discovered, the PH domain recruits diverse protein architectures to cellular membranes. PH domains constitute one of the largest protein superfamilies, and have diverged to regulate many different signaling proteins and modules such as Dbl homology (DH) and Tec homology (TH) domains. The ligands of approximately 70 PH domains have been validated by binding assays and complexed structures, allowing meaningful extrapolation across the entire superfamily. Here the Membrane Optimal Docking Area (MODA) program is used at a genome-wide level to identify all membrane docking PH structures and map their lipid-binding determinants. In addition to the linear sequence motifs which are employed for phosphoinositide recognition, the three dimensional structural features that allow peripheral membrane domains to approach and insert into the bilayer are pinpointed and can be predicted ab initio. The analysis shows that conserved structural surfaces distinguish which PH domains associate with membrane from those that do not. Moreover, the results indicate that lipid-binding PH domains can be classified into different functional subgroups based on the type of membrane insertion elements they project towards the bilayer.

  1. Membrane and Protein Interactions of the Pleckstrin Homology Domain Superfamily

    Directory of Open Access Journals (Sweden)

    Marc Lenoir

    2015-10-01

    Full Text Available The human genome encodes about 285 proteins that contain at least one annotated pleckstrin homology (PH domain. As the first phosphoinositide binding module domain to be discovered, the PH domain recruits diverse protein architectures to cellular membranes. PH domains constitute one of the largest protein superfamilies, and have diverged to regulate many different signaling proteins and modules such as Dbl homology (DH and Tec homology (TH domains. The ligands of approximately 70 PH domains have been validated by binding assays and complexed structures, allowing meaningful extrapolation across the entire superfamily. Here the Membrane Optimal Docking Area (MODA program is used at a genome-wide level to identify all membrane docking PH structures and map their lipid-binding determinants. In addition to the linear sequence motifs which are employed for phosphoinositide recognition, the three dimensional structural features that allow peripheral membrane domains to approach and insert into the bilayer are pinpointed and can be predicted ab initio. The analysis shows that conserved structural surfaces distinguish which PH domains associate with membrane from those that do not. Moreover, the results indicate that lipid-binding PH domains can be classified into different functional subgroups based on the type of membrane insertion elements they project towards the bilayer.

  2. A buffer insertion and simultaneous sizing timing optimization algorithm

    Institute of Scientific and Technical Information of China (English)

    Yin Guoli; Lin Zhenghui

    2006-01-01

    A path-based timing optimization algorithm for buffer insertion and simultaneous sizing is proposed.Firstly, candidate buffer insertion location and buffer size for each branch in a given routing path were obtained via localized timing optimization. Then, through evaluating each potential insertion against design objectives, potential optimal buffer insertion locations and sizes for the whole routing tree were determined. At last, by removing redundant buffer insertion operations which do not maximize S ( so ), given timing requirements are finally fulfilled through minimum number of buffers.

  3. Fungus- and wound-induced accumulation of mRNA containing a class II chitinase of the pathogenesis-related protein 4 (PR-4) family of maize.

    Science.gov (United States)

    Bravo, Juan Manuel; Campo, Sonia; Murillo, Isabel; Coca, Mária; San Segundo, Blanca

    2003-07-01

    Pathogenesis-related (PR) proteins are plant proteins that are induced in response to pathogen attack. PR proteins are grouped into independent families based on their sequences and properties. The PR-4 family comprises class I and class II chitinases. We have isolated a full-length cDNA encoding a chitinase from maize which shares a high degree of nucleotide and amino acid sequence homology with the class II chitinases of the PR-4 family of PR proteins. Our results indicate that fungal infection, and treatment either with fungal elicitors or with moniliformin, a mycotoxin produced by the fungus Fusarium moniliforme, increase the level of ZmPR4 mRNA. In situ mRNA hybridization analysis in sections obtained from fungus-infected germinating embryos revealed that ZmPR4 mRNA accumulation occurs in those cell types that first establish contact with the pathogen. ZmPR4 mRNA accumulation is also stimulated by treatment with silver nitrate whereas the application of the hormones gibberellic acid or acetylsalicylic acid has no effect. Wounding, or treatment with abscisic acid or methyl jasmonate, results in accumulation of ZmPR4 mRNA in maize leaves. Furthermore, the ZmPR4 protein was expressed in Escherichia coli, purified and used to obtain polyclonal antibodies that specifically recognized ZmPR4 in protein extracts from fungus-infected embryos. Accumulation of ZmPR4 mRNA in fungus-infected maize tissues was accompanied by a significant accumulation of the corresponding protein. The possible implications of these findings as part of the general defence response of maize plants against pathogens are discussed. PMID:13677464

  4. 一个新型的棉花几丁质酶基因%A Novel Cotton Gene Encoding a New Class of Chitinase

    Institute of Scientific and Technical Information of China (English)

    李骥; 刘进元

    2003-01-01

    在对外源水杨酸处理的低酚品系棉花(Gossypium hirsutum cv.CRI13)(中棉13)幼苗进行RT-PCR差异分析并分离出一个cDNA片段的基础上,采用电子克隆和分子克隆相结合的方法克隆出该片段的全长序列,并对其cDNA和核DNA序列进行分析,结果显示该基因是一个新型的几丁质酶基因,命名为GhChia7.推测的GhChia7氨基酸序列与Ⅰ和Ⅱ型几丁质酶的相同性仅有30%,其结构特征也与已鉴定的Ⅰ~Ⅳ有差异,是一个新型的几丁质酶(Ⅶ型).Northern杂交结果显示,该基因在棉花幼苗的根中以及棉花纤维中信号较强,且在棉花子叶中受水杨酸诱导表达,用7.5 mmol/L水杨酸处理18 h后mRNA水平达到最大值.本研究的结果显示GhChia7可能会在棉花抗病防卫反应中发挥重要作用.%A novel chitinase gene (GhChia7) was isolated from salicylic acid (SA)-treated cottoncotyledons and characterized by DNA sequence analysis of its cDNA and genomic DNA clone. The deducedamino acid sequence, designated as class Ⅶ chitinase, shares about 30% identity to class Ⅰ or Ⅱ chitinases,and does not correspond to any of the previously characterized classes Ⅰ -Ⅵ chitinases. Northern blot-ting analysis showed that the transcripts of GhChia7were abundant both in cotton fibers and in the roots of theseedlings. The accumulation of GhChia7mRNA in SA-treated cotyledons reached maximum at 7.5 mmol/L concentration after 18 h. Results indicate that GhChia7might play an important role in cotton' s activedefense response.

  5. Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen

    Science.gov (United States)

    Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

    2016-01-01

    Background The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. Objective To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Methods Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Results Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Conclusion Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy. PMID:27548813

  6. Glucanases and chitinases as causal agents in the protection of Acacia extrafloral nectar from infestation by phytopathogens.

    Science.gov (United States)

    González-Teuber, Marcia; Pozo, María J; Muck, Alexander; Svatos, Ales; Adame-Alvarez, Rosa M; Heil, Martin

    2010-03-01

    Nectars are rich in primary metabolites and attract mutualistic animals, which serve as pollinators or as an indirect defense against herbivores. Their chemical composition makes nectars prone to microbial infestation. As protective strategy, floral nectar of ornamental tobacco (Nicotiana langsdorffii x Nicotiana sanderae) contains "nectarins," proteins producing reactive oxygen species such as hydrogen peroxide. By contrast, pathogenesis-related (PR) proteins were detected in Acacia extrafloral nectar (EFN), which is secreted in the context of defensive ant-plant mutualisms. We investigated whether these PR proteins protect EFN from phytopathogens. Five sympatric species (Acacia cornigera, A. hindsii, A. collinsii, A. farnesiana, and Prosopis juliflora) were compared that differ in their ant-plant mutualism. EFN of myrmecophytes, which are obligate ant-plants that secrete EFN constitutively to nourish specialized ant inhabitants, significantly inhibited the growth of four out of six tested phytopathogenic microorganisms. By contrast, EFN of nonmyrmecophytes, which is secreted only transiently in response to herbivory, did not exhibit a detectable inhibitory activity. Combining two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with nanoflow liquid chromatography-tandem mass spectrometry analysis confirmed that PR proteins represented over 90% of all proteins in myrmecophyte EFN. The inhibition of microbial growth was exerted by the protein fraction, but not the small metabolites of this EFN, and disappeared when nectar was heated. In-gel assays demonstrated the activity of acidic and basic chitinases in all EFNs, whereas glucanases were detected only in EFN of myrmecophytes. Our results demonstrate that PR proteins causally underlie the protection of Acacia EFN from microorganisms and that acidic and basic glucanases likely represent the most important prerequisite in this defensive function. PMID:20023149

  7. Expression of the chitinase family glycoprotein YKL-40 in undifferentiated, differentiated and trans-differentiated mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Daniel J Hoover

    Full Text Available The glycoprotein YKL-40 (CHI3L1 is a secreted chitinase family protein that induces angiogenesis, cell survival, and cell proliferation, and plays roles in tissue remodeling and immune regulation. It is expressed primarily in cells of mesenchymal origin, is overexpressed in numerous aggressive carcinomas and sarcomas, but is rarely expressed in normal ectodermal tissues. Bone marrow-derived mesenchymal stem cells (MSCs can be induced to differentiate into various mesenchymal tissues and trans-differentiate into some non-mesenchymal cell types. Since YKL-40 has been used as a mesenchymal marker, we followed YKL-40 expression as undifferentiated MSCs were induced to differentiate into bone, cartilage, and neural phenotypes. Undifferentiated MSCs contain significant levels of YKL-40 mRNA but do not synthesize detectable levels of YKL-40 protein. MSCs induced to differentiate into chondrocytes and osteocytes soon began to express and secrete YKL-40 protein, as do ex vivo cultured chondrocytes and primary osteocytes. In contrast, MSCs induced to trans-differentiate into neurons did not synthesize YKL-40 protein, consistent with the general absence of YKL-40 protein in normal CNS parenchyma. However, these trans-differentiated neurons retained significant levels of YKL-40 mRNA, suggesting the mechanisms which prevented YKL-40 translation in undifferentiated MSCs remained in place, and that these trans-differentiated neurons differ in at least this way from neurons derived from neuronal stem cells. Utilization of a differentiation protocol containing β-mercaptoethanol resulted in cells that expressed significant amounts of intracellular YKL-40 protein that was not secreted, which is not seen in normal cells. Thus the synthesis of YKL-40 protein is a marker for MSC differentiation into mature mesenchymal phenotypes, and the presence of untranslated YKL-40 mRNA in non-mesenchymal cells derived from MSCs reflects differences between differentiated and

  8. INSERTION DEVICE UPGRADE PLANS AT THE NSLS.

    Energy Technology Data Exchange (ETDEWEB)

    TANABE, T.; BLEDNYKH, A.; HARDER, D.; LEHECKA, M.; RAKOWSKY, G.; SKARITKA, J.

    2005-05-16

    This paper describes plans to upgrade insertion devices (IDs) at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, U.S.A. The aging wiggler (W120) at X25 is being replaced by a 1 m long in-vacuum mini-gap undulator (MGU-X25) optimized for a dedicated macromolecular crystallography program. A new, 1/3 m long, undulator (MGU or SCU-X9), will be installed between a pair of RF cavities at X9, and will serve a new beamline dedicated for small angle x-ray scattering (SAXS). Both IDs will have provision for cryocooling the NdFeB hybrid arrays to 150K to raise the field and K-value and to obtain better spectral coverage. Design issues of the devices and other considerations, especially magnetic measurement at low temperature, will be discussed.

  9. Regulatory perspective on incomplete control rod insertions

    Energy Technology Data Exchange (ETDEWEB)

    Chatterton, M.

    1997-01-01

    The incomplete control rod insertions experienced at South Texas Unit 1 and Wolf Creek are of safety concern to the NRC staff because they represent potential precursors to loss of shutdown margin. Even before it was determined if these events were caused by the control rods or by the fuel there was an apparent correlation of the problem with high burnup fuel. It was determined that there was also a correlation between high burnup and high drag forces as well as with rod drop time histories and lack of rod recoil. The NRC staff initial actions were aimed at getting a perspective on the magnitude of the problem as far as the number of plants and the amount of fuel that could be involved, as well as the safety significance in terms of shutdown margin. As tests have been performed and data has been analyzed the focus has shifted more toward understanding the problem and the ways to eliminate it. At this time the staff`s understanding of the phenomena is that it was a combination of factors including burnup, power history and temperature. The problem appears to be very sensitive to these factors, the interaction of which is not clearly understood. The model developed by Westinghouse provides a possible explanation but there is not sufficient data to establish confidence levels and sensitivity studies involving the key parameters have not been done. While several fixes to the problem have been discussed, no definitive fixes have been proposed. Without complete understanding of the phenomena, or fixes that clearly eliminate the problem the safety concern remains. The safety significance depends on the amount of shutdown margin lost due to incomplete insertion of the control rods. Were the control rods to stick high in the core, the reactor could not be shutdown by the control rods and other means such as emergency boration would be required.

  10. Exploring Beta-Amyloid Protein Transmembrane Insertion Behavior and Residue-Specific Lipid Interactions in Lipid Bilayers Using Multiscale MD Simulations

    Science.gov (United States)

    Qiu, Liming; Vaughn, Mark; Cheng, Kelvin

    2013-03-01

    Beta-amyloid (Abeta) interactions with neurons are linked to Alzheimer's. Using a multiscale MD simulation strategy that combines the high efficiency of phase space sampling of coarse-grained MD (CGD) and the high spatial resolution of Atomistic MD (AMD) simulations, we studied the Abeta insertion dynamics in cholesterol-enriched and -depleted lipid bilayers that mimic the neuronal membranes domains. Forward (AMD-CGD) and reverse (CGD-AMD) mappings were used. At the atomistic level, cholesterol promoted insertion of Abeta with high (folded) or low (unfolded) helical contents of the lipid insertion domain (Lys28-Ala42), and the insertions were stabilized by the Lys28 snorkeling and Ala42-anchoring to the polar lipid groups of the bilayer up to 200ns. After the forward mapping, the folded inserted state switched to a new extended inserted state with the Lys28 descended to the middle of the bilayer while the unfolded inserted state migrated to the membrane surface up to 4000ns. The two new states remained stable for 200ns at the atomistic scale after the reverse mapping. Our results suggested that different Abeta membrane-orientation states separated by free energy barriers can be explored by the multiscale MD more effectively than by Atomistic MD simulations alone. NIH RC1-GM090897-02

  11. Protein domain prediction

    NARCIS (Netherlands)

    Ingolfsson, Helgi; Yona, Golan

    2008-01-01

    Domains are considered to be the building blocks of protein structures. A protein can contain a single domain or multiple domains, each one typically associated with a specific function. The combination of domains determines the function of the protein, its subcellular localization and the interacti

  12. Wear mechanisms of WC-Co drill bit inserts against alumina counterface under dry friction: Part 2 — Graded WC-Co inserts

    OpenAIRE

    Yahiaoui, Malik; Paris, Jean-Yves; Denape, Jean; Colin, Christophe; Ther, Olivier; Dourfaye, Alfazazi

    2015-01-01

    The tribological behaviour of innovative graded cemented carbide inserts were studied by using a rotary tribometer and abrasive alumina counterfaces. This work completes the study made on commercial inserts with homogeneous cobalt content. Inserts with three types of graduation processes were considered: inserts with borides WCoB phases, imbibed inserts and inserts combining both processes (i.e. inserts with reactive imbibition). Physicochemical and mechanical measurements show that the WCoB ...

  13. Human YKL39 (chitinase 3-like protein 2), an osteoarthritis-associated gene, enhances proliferation and type II collagen expression in ATDC5 cells

    International Nuclear Information System (INIS)

    Highlights: ► hYKL-39 expression is increased in osteoarthritic articular chondrocytes. ► To examine the molecular functions of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in chondrocytic ATDC5 cells. ► hYKL-39 enhanced proliferation and colony formation in ATDC5 cells. ► hYKL-39 increased type II collagen expression in ATDC5 cells treated with chondrogenic medium. -- Abstract: Human YKL39 (chitinase 3-like protein 2/CHI3L2) is a secreted 39 kDa protein produced by articular chondrocytes and synoviocytes. Recent studies showed that hYKL-39 expression is increased in osteoarthritic articular chondrocytes suggesting the involvement of hYKL-39 in the progression of osteoarthritis (OA). However little is known regarding the molecular function of hYKL-39 in joint homeostasis. Sequence analyses indicated that hYKL-39 has significant identity with the human chitotorisidase family molecules, although it is considered that hYKL-39 has no enzymatic activity since it lacks putative chitinase catalytic motif. In this study, to examine the molecular function of hYKL-39 in chondrocytes, we overexpressed hYKL-39 in ATDC5 cells. Here we report that hYKL-39 enhances colony forming activity, cell proliferation, and type II collagen expression in these cells. These data suggest that hYKL-39 is a novel growth and differentiation factor involved in cartilage homeostasis

  14. Transformation of blackgram (Vigna mungo (L.) Hepper) by barley chitinase and ribosome-inactivating protein genes towards improving resistance to Corynespora leaf spot fungal disease.

    Science.gov (United States)

    Chopra, Rajan; Saini, Raman

    2014-12-01

    Blackgram (Vigna mungo (L.) Hepper), an important grain legume crop, is sensitive to many fungal pathogens including Corynespora cassiicola, the causal agent of corynespora leaf spot disease. In the present study, plasmid pGJ42 harboring neomycin phosphotransferase (nptII) a selectable marker gene, the barley antifungal genes chitinase (AAA56786) and ribosome-inactivating protein (RIP; AAA32951) were used for the transformation, to develop fungal resistance for the first time in blackgram. The presence and integration of transgene into the blackgram genome was confirmed by PCR and Southern analysis with an overall transformation frequency of 10.2 %. Kanamycin selection and PCR analysis of T0 progeny revealed the inheritance of transgene in Mendelian fashion (3:1). Transgenic plants (T1), evaluated for fungal resistance by in vitro antifungal assay, arrested the growth of C. cassiicola up to 25-40 % over the wild-type plants. In fungal bio-assay screening, the transgenic plants (T1) sprayed with C. cassiicola spores showed a delay in onset of disease along with their lesser extent in terms of average number of diseased leaves and reduced number and size of lesions. The percent disease protection among different transformed lines varies in the range of 27-47 % compare to control (untransformed) plants. These results demonstrate potentiality of chitinase and RIP from a heterologous source in developing fungal disease protection in blackgram and can be helpful in increasing the production of blackgram.

  15. The Role of CHI3L1 (Chitinase-3-Like-1 in the Pathogenesis of Infections in Burns in a Mouse Model.

    Directory of Open Access Journals (Sweden)

    Stefan Bohr

    Full Text Available In severe burn injury the unique setting of a depleted, dysfunctional immune system along with a loss of barrier function commonly results in opportunistic infections that eventually proof fatal. Unfortunately, the dynamic sequence of bacterial contamination, colonization and eventually septic invasion with bacteria such as Pseudomonas species is still poorly understood although a limiting factor in clinical decision making. Increasing evidence supports the notion that inhibition of bacterial translocation into the wound site may be an effective alternative to prevent infection. In this context we investigated the role of the mammalian Chitinase-3-Like-1 (CHI3L1 non-enyzmatic protein predominately expressed on epithelial as well as innate immune cells as a potential bacterial-translocation-mediating factor. We show a strong trend that a modulation of chitinase expression is likely to be effective in reducing mortality rates in a mouse model of burn injury with superinfection with the opportunistic PA14 Pseudomonas strain, thus demonstrating possible clinical leverage.

  16. Ocular inserts - Advancement in therapy of eye diseases

    Directory of Open Access Journals (Sweden)

    Anita Kumari

    2010-01-01

    Full Text Available The ocular insert represents a significant advancement in the therapy of eye disease. Ocular inserts are defined as sterile, thin, multilayered, drug-impregnated, solid or semisolid consistency devices placed into the cul-de-sac or conjuctival sac, whose size and shape are especially designed for ophthalmic application. They are composed of a polymeric support that may or may not contain a drug. The drug can later be incorporated as dispersion or a solution in the polymeric support. They offer several advantages as increased ocular residence and sustained release of medication into the eye. The insert includes a body portion sized to position within a lachrymal canaliculus of the eyelid. The inserts are classified according to their solubility as insoluble, soluble, or bioerodible inserts. The release of drug from the insert depends upon the diffusion, osmosis, and bioerosion of the drug, and this article is an attempt to present a brief about this newer drug delivery system.

  17. The Effect of Windings on ADSL Transformer Insertion Losses

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiao-na; LAN Zhong-wen; CHEN Sheng-ming; ZHANG Huai-wu; SU Hua

    2007-01-01

    Insertion loss (IL) is one of the important parameters of asymmetrical digital subscriber loop (ADSL) transformers. In different frequency bands, the factors that affect insertion loss are different. Windings mainly affect insertion loss in mid and high frequency bands.The effects of winding ways, winding wire diameter and winding turns on insertion loss were discussed. The presented experiment shows that the insertion loss of an ADSL transformer could be under 0.4 dB in mid frequency band when the winding is 30 turns, in which the ADSL transformer satisfies the requirement of total harmonic distortion (THD). Our experiments also show that the sandwich winding structure is better than the side by side winding structure and the twisted-pair winding structure, and the increase of winding diameter is one means to reduce insertion losses of an ADSL transformer in mid frequency band.

  18. Insertion torque versus mechanical resistance of mini- implants inserted in different cortical thickness

    Directory of Open Access Journals (Sweden)

    Renata de Faria Santos

    2014-06-01

    Full Text Available OBJECTIVE: This study aimed to measure insertion torque, tip mechanical resistance to fracture and transmucosal neck of mini-implants (MI (Conexão Sistemas de PróteseT, as well as to analyze surface morphology. METHODS: Mechanical tests were carried out to measure the insertion torque of MIs in different cortical thicknesses, and tip mechanical resistance to fracture as well as transmucosal neck of MIs. Surface morphology was assessed by scanning electron microscopy (SEM before and after the mechanical tests. RESULTS: Values of mechanical resistance to fracture (22.14 N.cm and 54.95 N.cm were higher and statistically different (P 0.05 to torsional fracture in the tip of MI (22.14 N.cm when 3 mm cortical thickness (16.11 N.cm and dense bone (23.95 N.cm were used. Torsional fracture of the transmucosal neck (54.95 N.cm was higher and statistically different (P < 0.05 from insertion torsional strength in all tested situations. SEM analysis showed that the MIs had the same smooth surface when received from the manufacturer and after the mechanical tests were performed. Additionally, no significant marks resulting from the manufacturing process were observed. CONCLUSION: All mini-implants tested presented adequate surface morphology. The resistance of mini-implants to fracture safely allows placement in 1 and 2-mm cortical thickness. However, in 3-mm cortical thickness and dense bones, pre-drilling with a bur is recommended before insertion.

  19. EXPLORATION ON SCALABILITY OF DATABASE BULK INSERTION WITH MULTITHREADING

    OpenAIRE

    Boon-Wee Low; Boon-Yaik Ooi; and Chee-Siang Wong

    2011-01-01

    The advancement of database engine and multi-core processors technologies have enable database insertion to be implemented concurrently via multithreading programming. The objective of this work is to evaluate the performance of using multithreading technique to perform database insertion of large data set with known size to enhance the performance of data access layer (DAL) particularly on the bulk-insertion operation. The performance evaluation includes techniques such as using single datab...

  20. A CRITICAL APPRAISAL OF PACKAGE INSERTS IN INDIA

    Directory of Open Access Journals (Sweden)

    Makbool Ali M.

    2016-06-01

    Full Text Available formation is a Package Insert. It is a printed leaflet that contains information based on regulatory guidelines for the safe and effective use of a drug. Incomplete and incorrect product information may have serious consequences including disability or death. In India, the concept of package insert is governed by the Drugs and Cosmetics Act (1940 and Rules (1945. Keeping this in mind, this study was designed to assess the presentation and completeness of drug information provided in the currently available package inserts for allopathic drugs in India. AIM To evaluate the presentation and completeness of drug information provided in the currently available package inserts for allopathic drugs in India. OBJECTIVES To evaluate drug information in package inserts according to headings mentioned in Section 6.2 and 6.3 of Schedule D, Drugs and Cosmetics Rules, 1945. MATERIAL AND METHODS Package inserts accompanying allopathic medicines were obtained from a drug store and three pharmacies around a tertiary care centre in Western India on request over a 1-month period. The package inserts were included in the study and analysed for the presentation and completeness of information according to the headings mentioned in Section 6.2 and Section 6.3 of Schedule D, The Drugs and Cosmetics Rules, 1945. RESULTS 110 package inserts were analysed in the study. None of the reviewed package insert contained all the sections as required by the Drugs and Cosmetic Rules. CONCLUSION To avoid medication errors due to deficits in drug information in package inserts, tighter monitoring of package inserts by regulatory authorities is recommended. Steps should be taken to ensure that the information in the package inserts follows a standard layout for easy and convenient comprehension.

  1. Technical note: Computer-manufactured inserts for prosthetic sockets.

    Science.gov (United States)

    Sanders, Joan E; McLean, Jake B; Cagle, John C; Gardner, David W; Allyn, Katheryn J

    2016-08-01

    The objective of this research was to use computer-aided design software and a tabletop 3-D additive manufacturing system to design and fabricate custom plastic inserts for trans-tibial prosthesis users. Shape quality of inserts was tested right after they were inserted into participant's test sockets and again after four weeks of wear. Inserts remained properly positioned and intact throughout testing. Right after insertion the inserts caused the socket to be slightly under-sized, by a mean of 0.11mm, approximately 55% of the thickness of a nylon sheath. After four weeks of wear the under-sizing was less, averaging 0.03mm, approximately 15% of the thickness of a nylon sheath. Thus the inserts settled into the sockets over time. If existing prosthetic design software packages were enhanced to conduct insert design and to automatically generate fabrication files for manufacturing, then computer manufactured inserts may offer advantages over traditional methods in terms of speed of fabrication, ease of design, modification, and record keeping. PMID:27212209

  2. Threaded insert for compact cryogenic-capable pressure vessels

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa-Loza, Francisco; Ross, Timothy O.; Switzer, Vernon A.; Aceves, Salvador M.; Killingsworth, Nicholas J.; Ledesma-Orozco, Elias

    2015-06-16

    An insert for a cryogenic capable pressure vessel for storage of hydrogen or other cryogenic gases at high pressure. The insert provides the interface between a tank and internal and external components of the tank system. The insert can be used with tanks with any or all combinations of cryogenic, high pressure, and highly diffusive fluids. The insert can be threaded into the neck of a tank with an inner liner. The threads withstand the majority of the stress when the fluid inside the tank that is under pressure.

  3. The ATLAS Insertable B-Layer Project

    CERN Document Server

    Miucci, A; The ATLAS collaboration

    2014-01-01

    The ATLAS experiment will upgrade its Pixel Detector with the installation of a new pixel layer in 2013-14. The new sub-detector, named Insertable B-layer (IBL), will be installed between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been de- veloped. Furthermore, the physics performance should be improved through the reduction of pixel size while a low material budget should be imposed. A new mechanical support using lightweight staves and a CO2 based cooling system is used. An overview of the IBL project and the status of the production of staves and the qualification of the assembly procedure, the loaded module electrical integrity and the read-out chain will be presented.

  4. APS insertion devices: Recent developments and results

    International Nuclear Information System (INIS)

    The Advanced Photon Source (APS) now has a total of 23 insertion devices (IDs). Over two-thirds of them are installed on the storage ring. The installed devices include 18, 27 and 55 mm-period undulators; an 85 mm-period wiggler; a 16 cm-period elliptical multipole wiggler; and many 33 mm-period undulators. Most of the IDs occupy storage-ring straight sections equipped with 8 mm vertical-aperture vacuum chambers. All of the IDs were measured magnetically at the APS and, in most cases, underwent a final magnetic tuning in order to minimize variation in the various integrals of the field through the ID over the full gap range. Special shimming techniques to correct magnetic field parameters in appropriate gap-dependent ways were developed and applied. Measurements of the closed-orbit distortion as a function of the ID gap variation have been completed, and results are in a good agreement with magnetic measurements. Spectral diagnostics of the ID radiation, including measurements of the absolute spectral flux, brilliance and polarization, show excellent agreement between calculated and measured results. Studies of the sensitivity of IDs to radiation exposure and measurements of the dose rate received by the IDs are in progress

  5. The LysM Receptor-Like Kinase LysM RLK1 Is Required to Activate Defense and Abiotic-Stress Responses Induced by Overexpression of Fungal Chitinases in Arabidopsis Plants

    Institute of Scientific and Technical Information of China (English)

    Yariv Brotman; Ada Viterbo; Udi Landau; Smadar Pnini; Jan Lisec; Salma Balazadeh; Bernd Mueller-Roeber; Aviah Zilberstein; Lothar Willmitzer; Ilan Chet

    2012-01-01

    Application of crab shell chitin or pentamer chitin oligosaccharide to Arabidopsis seedlings increased tolerance to salinity in wild-type but not in knockout mutants of the LysM Receptor-Like Kinase1 (CERK1/LysM RLK1) gene,known to play a critical role in signaling defense responses induced by exogenous chitin.Arabidopsis plants overexpressing the endochitinase chit36 and hexoaminidase excy1 genes from the fungus Trichoderma asperelleoides T203 showed increased tolerance to salinity,heavy-metal stresses,and Botrytis cinerea infection.Resistant lines,overexpressing fungal chitinases at different levels,were outcrossed to lysm rlk1 mutants.Independent homozygous hybrids lost resistance to biotic and abiotic stresses,despite enhanced chitinase activity.Expression analysis of 270 stress-related genes,including those induced by reactive oxygen species (ROS) and chitin,revealed constant up-regulation (at least twofold) of 10 genes in the chitinase-overexpressing line and an additional 76 salt-induced genes whose expression was not elevated in the lysm rlk1 knockout mutant or the hybrids harboring the mutation.These findings elucidate that chitin-induced signaling mediated by LysM RLK1 receptor is not limited to biotic stress response but also encompasses abiotic-stress signaling and can be conveyed by ectopic expression of chitinases in plants.

  6. Selenocysteine biosynthesis and insertion machinery in Naegleria gruberi.

    Science.gov (United States)

    da Silva, M T A; Caldas, V E A; Costa, F C; Silvestre, D A M M; Thiemann, O H

    2013-04-01

    Selenium (Se) is an essential trace element primarily found in selenoproteins as the 21st amino acid (selenocysteine, Sec, or U). Selenoproteins play an important role in growth and proliferation and are typically involved in cellular redox balance. Selenocysteine is encoded by an in-frame UGA codon specified by a stem-loop structure, the Sec insertion sequence element (SECIS), which, in eukaryotes, is located in the 3'-untranslated region (UTR). The availability of the Naegleria gruberi (ATCC 30224) genome sequence and the use of this organism as a model system for the pathogenic amoeba N. fowleri allowed us to investigate the Sec incorporation pathway in this primitive eukaryote. Using bioinformatics tools, we identified gene sequences encoding PSTK (O-phosphoseryl-tRNA(Sec) kinase), SepSecS (O-phosphoseryl-tRNA:selenocysteinyl-tRNA synthase), SelD/SPS2 (selenophosphate synthetase), EFSec (selenocysteine-specific elongation factor) and SBP (SECIS binding protein). These findings were confirmed by RT-PCR and by sequencing. A potential tRNA(Ser)Sec (SelC) gene and a putative selenoprotein with sequence similarity to a mitochondrial thioredoxin reductase (TR3) were also identified. Our results show that the selenocysteine incorporation machinery is indeed present in N. gruberi. Interestingly, the SelD/SPS2 gene is 2214 bp in length and contains two distinct domains. The N-terminal region shows sequence similarity to predicted methyltransferase proteins, and the C-terminal region is homologous to prokaryotic SelD/SPS2. Our results suggest the possibility of novel selenoproteins.

  7. Discovering sequence motifs with arbitrary insertions and deletions.

    Directory of Open Access Journals (Sweden)

    Martin C Frith

    2008-04-01

    Full Text Available BIOLOGY IS ENCODED IN MOLECULAR SEQUENCES: deciphering this encoding remains a grand scientific challenge. Functional regions of DNA, RNA, and protein sequences often exhibit characteristic but subtle motifs; thus, computational discovery of motifs in sequences is a fundamental and much-studied problem. However, most current algorithms do not allow for insertions or deletions (indels within motifs, and the few that do have other limitations. We present a method, GLAM2 (Gapped Local Alignment of Motifs, for discovering motifs allowing indels in a fully general manner, and a companion method GLAM2SCAN for searching sequence databases using such motifs. glam2 is a generalization of the gapless Gibbs sampling algorithm. It re-discovers variable-width protein motifs from the PROSITE database significantly more accurately than the alternative methods PRATT and SAM-T2K. Furthermore, it usefully refines protein motifs from the ELM database: in some cases, the refined motifs make orders of magnitude fewer overpredictions than the original ELM regular expressions. GLAM2 performs respectably on the BAliBASE multiple alignment benchmark, and may be superior to leading multiple alignment methods for "motif-like" alignments with N- and C-terminal extensions. Finally, we demonstrate the use of GLAM2 to discover protein kinase substrate motifs and a gapped DNA motif for the LIM-only transcriptional regulatory complex: using GLAM2SCAN, we identify promising targets for the latter. GLAM2 is especially promising for short protein motifs, and it should improve our ability to identify the protein cleavage sites, interaction sites, post-translational modification attachment sites, etc., that underlie much of biology. It may be equally useful for arbitrarily gapped motifs in DNA and RNA, although fewer examples of such motifs are known at present. GLAM2 is public domain software, available for download at http://bioinformatics.org.au/glam2.

  8. Controlled language and information on vaccines: application to package inserts.

    Science.gov (United States)

    Renahy, Julie; Vuitton, Dominique A; Rath, Barbara; Thomas, Izabella; de Grivel, Valerie; Cardey, Sylviane

    2015-01-01

    Any ambiguity in texts used in the communication about vaccines can not only interfere with comprehension, but also generate safety and liability issues. Within a survey on the quality of written protocols for at-risk interventional procedures and sanitary crises, we analyzed documents relating to vaccination, and among them, the "package-leaflet" of an anti-H1N1 influenza vaccine, widely disseminated to the public in 2009-2010. Among the most common mistakes, we observed that 1) language was not always adjusted to the non-specialist's level of knowledge; 2) chronology, logic, consistency, and homogeneity were often missing; 3) crucial pieces of information were disseminated all over the text, 4) use of the passive voice did not distinguish between instructions and information; 5) use of synonyms could be misleading and impair translation. We propose the use of "Controlled language" (CL) to improve the situation. By constraining lexicon, grammar and syntax, CL is a way to write documents that are clear, accurate and devoid of ambiguity. However, the set of rules necessary to write in CL is difficult to memorize. We thus developed authoring software (Rédacticiel Prolipsia) to make the creation of a CL by linguists and its use by health professionals easy and adapted to any domain. It may considerably improve the writing of vaccine package inserts/leaflets. It could be used to write information documents about vaccines and their safety, and operating procedures for professionals to prepare, store, and administer vaccines, decide upon proper indication of vaccines, and follow patients after vaccine injection.

  9. Structural and histone binding ability characterizations of human PWWP domains.

    Directory of Open Access Journals (Sweden)

    Hong Wu

    Full Text Available BACKGROUND: The PWWP domain was first identified as a structural motif of 100-130 amino acids in the WHSC1 protein and predicted to be a protein-protein interaction domain. It belongs to the Tudor domain 'Royal Family', which consists of Tudor, chromodomain, MBT and PWWP domains. While Tudor, chromodomain and MBT domains have long been known to bind methylated histones, PWWP was shown to exhibit histone binding ability only until recently. METHODOLOGY/PRINCIPAL FINDINGS: The PWWP domain has been shown to be a DNA binding domain, but sequence analysis and previous structural studies show that the PWWP domain exhibits significant similarity to other 'Royal Family' members, implying that the PWWP domain has the potential to bind histones. In order to further explore the function of the PWWP domain, we used the protein family approach to determine the crystal structures of the PWWP domains from seven different human proteins. Our fluorescence polarization binding studies show that PWWP domains have weak histone binding ability, which is also confirmed by our NMR titration experiments. Furthermore, we determined the crystal structures of the BRPF1 PWWP domain in complex with H3K36me3, and HDGF2 PWWP domain in complex with H3K79me3 and H4K20me3. CONCLUSIONS: PWWP proteins constitute a new family of methyl lysine histone binders. The PWWP domain consists of three motifs: a canonical β-barrel core, an insertion motif between the second and third β-strands and a C-terminal α-helix bundle. Both the canonical β-barrel core and the insertion motif are directly involved in histone binding. The PWWP domain has been previously shown to be a DNA binding domain. Therefore, the PWWP domain exhibits dual functions: binding both DNA and methyllysine histones. ENHANCED VERSION: This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web

  10. Mutational analysis of a ras catalytic domain

    DEFF Research Database (Denmark)

    Willumsen, B M; Papageorge, A G; Kung, H F;

    1986-01-01

    We used linker insertion-deletion mutagenesis to study the catalytic domain of the Harvey murine sarcoma virus v-rasH transforming protein, which is closely related to the cellular rasH protein. The mutants displayed a wide range of in vitro biological activity, from those that induced focal...... transformation of NIH 3T3 cells with approximately the same efficiency as the wild-type v-rasH gene to those that failed to induce any detectable morphologic changes. Correlation of transforming activity with the location of the mutations enabled us to identify three nonoverlapping segments within the catalytic...

  11. The Evolutionary Relationship of the Domain Architectures in the RhoGEF-containing Proteins

    Institute of Scientific and Technical Information of China (English)

    Qing-Lan Sun; Hong-Jun Zhou; Kui Lin

    2005-01-01

    Domain insertions and deletions lead to variations in the domain architectures of the proteins from their common ancestor. In this work, we investigated four groups of the RhoGEF-containing proteins from different organisms with domain architectures RhoGEF-PH-SH3, SH3-RhoGEF-PH, RhoGEF-PH, and SH3-RhoGEF defined in the Pfam database. The phylogenetic trees were constructed using each individual domain and/or the combinations of all the domains. The phylogenetic analysis suggests that RhoGEF-PH-SH3 and SH3-RhoGEF-PH might have evolved from RhoGEF-PH through the insertion of SH3 independently, while SH3-RhoGEF of proteins in fruit fly might have evolved from SH3-RhoGEF-PH by the degeneration of PH domain.

  12. Load beam unit replaceable inserts for dry coal extrusion pumps

    Science.gov (United States)

    Saunders, Timothy; Brady, John D.

    2012-11-13

    A track assembly for a particulate material extrusion pump according to an exemplary aspect of the present disclosure includes a link assembly with a roller bearing. An insert mounted to a load beam located such that the roller bearing contacts the insert.

  13. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  14. 21 CFR 310.515 - Patient package inserts for estrogens.

    Science.gov (United States)

    2010-04-01

    ... recent revision of the patient package insert. (d) Guidance language. The Food and Drug Administration... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Patient package inserts for estrogens. 310.515 Section 310.515 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  15. Analysis of the Sherlock II tip location system for inserting peripherally inserted central venous catheters.

    Science.gov (United States)

    Lelkes, Valdis; Kumar, Abhishek; Shukla, Pratik A; Contractor, Sohail; Rutan, Thomas

    2013-01-01

    Peripherally inserted central catheters (PICCs) are frequently placed at the bedside. The purpose of our study was to evaluate the efficacy of the Sherlock II tip location system (Bard Access Systems, Salt Lake City, UT), which offers electromagnetic detection of the PICC tip to assist the operator in guiding the tip to a desired location. We performed a retrospective review of patients who had a bedside PICC using the Sherlock II tip location system. Three hundred seventy-five of 384 patients (97.7%) had the catheter tip positioned appropriately. Our results suggest that the Sherlock II tip location system is an efficacious system for bedside PICC placement.

  16. A new way to rapidly create functional, fluorescent fusion proteins: random insertion of GFP with an in vitro transposition reaction

    Directory of Open Access Journals (Sweden)

    Jakobsdottir Klara B

    2002-06-01

    Full Text Available Abstract Background The jellyfish green fluorescent protein (GFP can be inserted into the middle of another protein to produce a functional, fluorescent fusion protein. Finding permissive sites for insertion, however, can be difficult. Here we describe a transposon-based approach for rapidly creating libraries of GFP fusion proteins. Results We tested our approach on the glutamate receptor subunit, GluR1, and the G protein subunit, αs. All of the in-frame GFP insertions produced a fluorescent protein, consistent with the idea that GFP will fold and form a fluorophore when inserted into virtually any domain of another protein. Some of the proteins retained their signaling function, and the random nature of the transposition process revealed permissive sites for insertion that would not have been predicted on the basis of structural or functional models of how that protein works. Conclusion This technique should greatly speed the discovery of functional fusion proteins, genetically encodable sensors, and optimized fluorescence resonance energy transfer pairs.

  17. Improving protein crystal quality by selective removal of a Ca2+-dependent membrane-insertion loop

    International Nuclear Information System (INIS)

    Protein engineering dramatically enhances the quality of crystals of a Ca2+-dependent membrane-binding protein. Lipoxygenases (LOXs) catalyze the regiospecific and stereospecific dioxygenation of polyunsaturated membrane-embedded fatty acids. A Ca2+-dependent membrane-binding function was localized to the amino-terminal C2-like domain of 8R-lipoxygenase (8R-LOX) from the soft coral Plexaura homomalla. The 3.2 Å crystal structure of 8R-LOX and spectroscopic data suggested that Ca2+ stabilizes two membrane-insertion loops. Analysis of the protein packing contacts in the crystal lattice indicated that the conformation of one of the two loops complicated efforts to improve the resolution of the X-ray data. A deletion mutant of 8R-LOX in which the corresponding membrane-insertion loop is absent (Δ41–45:GSLOX) was engineered. Removal of the membrane-insertion loop dramatically increases the protein yield from bacterial cultures and the quality of the crystals obtained, resulting in a better than 1 Å improvement in the resolution of the diffraction data

  18. Quantum chemical and topological study on the insertion reaction of dichlorcarbene with acetaldehyde

    Institute of Scientific and Technical Information of China (English)

    LI ZhiFeng; ZHU YuanCheng; YANG Sheng; LU XiaoQuan

    2008-01-01

    The insertion reaction mechanisms of siglet and striglet CCI2with CH3CHO have been studied by using the DFT, NBO, CCSD(T) and AIM method. The geometries of reactions, transition state and products were completely optimized by B3LYP/6-31G(d). All the energy of the species was obtained at the CCSD(T)/6-31G(d,p) level. The calculated results indicated that all the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCI2can not only insert the Cα--H (reaction Ⅰ) but also can react with Cβ--H (reaction Ⅱ). There are three main existing pathways and the products are P1 (CH3COHCCI2), P2 (CH2COHCHCI2) and P4[CHCI2CHCHOH] respectively. Reaction Ⅱ happens more easily according to the energy changes and the barrier in rate-controlling step. In addition, the important geometries in domain pathways have been studied by AIM theory. And also, the energy changes of H in the inserted C--H bond have been investigated.

  19. Report on converging insert moulding with µ-IM

    DEFF Research Database (Denmark)

    Islam, Aminul

    Task 5.2.1 deals with the technical feasibility of converging the state-of-the-art µ IM process with insert moulding to offer a wide range of multi-material µ components. The main objective of this deliverable is to summarize state-of-the-art information and to make the guideline needed for the...... convergence. In particular the following aspects are summed up in the deliverable:  Need for converging insert moulding with µ-IM  Objectives and expected outcome from task 5.2.1  State-of-the-art micro insert moulding and different scenario of micro insert moulding  Challenges ahead of converging insert......-IM. Besides this fact current deliverable will provide state-of-the-art information for technology convergence and ways to overcome challenges to use convergent technologies in industrial productions....

  20. Gas turbine nozzle vane insert and methods of installation

    Science.gov (United States)

    Miller, William John; Predmore, Daniel Ross; Placko, James Michael

    2002-01-01

    A pair of hollow elongated insert bodies are disposed in one or more of the nozzle vane cavities of a nozzle stage of a gas turbine. Each insert body has an outer wall portion with apertures for impingement-cooling of nozzle wall portions in registration with the outer wall portion. The insert bodies are installed into the cavity separately and spreaders flex the bodies toward and to engage standoffs against wall portions of the nozzle whereby the designed impingement gap between the outer wall portions of the insert bodies and the nozzle wall portions is achieved. The spreaders are secured to the inner wall portions of the insert bodies and the bodies are secured to one another and to the nozzle vane by welding or brazing.

  1. Controlling Posture and Vergence Eye Movements in Quiet Stance: Effects of Thin Plantar Inserts.

    Directory of Open Access Journals (Sweden)

    A Foisy

    Full Text Available The purpose of this study was to assess properties of vergence and saccade eye movements as well as posture in quiet stance, and the effects of thin plantar inserts upon postural and oculomotor control. The performances of 36 young healthy subjects were recorded by a force platform and an eye tracker in three testing conditions: without plantar stimulation, with a 3 millimetre-thick plantar insert, either a Medial or a Lateral Arch Support (MAS/LAS. The results showed a decrease of the Surface and Variance of Speed and a more posterior position of the CoP with either stimulation compared with the control condition. The fractal analysis showed a decrease with MAS. Wavelet analysis in the time-frequency domain revealed an increase in the Cancelling Time of the low frequency band with MAS. These results suggest a better stability for a lower energy cost. Concerning eye movements, the inserts influenced only vergence (not saccades: MAS caused an increase of the phasic amplitude of divergence, and conversely a decrease of the tonic amplitude. In contrast, LAS caused an increase of the tonic amplitude of convergence. Thus, MAS renders divergence less visually driven, while LAS renders convergence more visually driven. We conclude that the CNS uses the podal signal for both postural and vergence control via specific mechanisms. Plantar inserts have an influence upon posture and vergence movements in a different way according to the part of the foot sole being stimulated. These results can be useful to clinicians interested in foot or eye.

  2. Toward automated cochlear implant insertion using tubular manipulators

    Science.gov (United States)

    Granna, Josephine; Rau, Thomas S.; Nguyen, Thien-Dang; Lenarz, Thomas; Majdani, Omid; Burgner-Kahrs, Jessica

    2016-03-01

    During manual cochlear implant electrode insertion the surgeon is at risk to damage the intracochlear fine-structure, as the electrode array is inserted through a small opening in the cochlea blindly with little force-feedback. This paper addresses a novel concept for cochlear electrode insertion using tubular manipulators to reduce risks of causing trauma during insertion and to automate the insertion process. We propose a tubular manipulator incorporated into the electrode array composed of an inner wire within a tube, both elastic and helically shaped. It is our vision to use this manipulator to actuate the initially straight electrode array during insertion into the cochlea by actuation of the wire and tube, i.e. translation and slight axial rotation. In this paper, we evaluate the geometry of the human cochlea in 22 patient datasets in order to derive design requirements for the manipulator. We propose an optimization algorithm to automatically determine the tube set parameters (curvature, torsion, diameter, length) for an ideal final position within the cochlea. To prove our concept, we demonstrate that insertion can be realized in a follow-the-leader fashion for 19 out of 22 cochleas. This is possible with only 4 different tube/wire sets.

  3. Immediate post-placental IUD insertion: the expulsion problem.

    Science.gov (United States)

    Thiery, M; Van Kets, H; Van der Pas, H

    1985-04-01

    This paper reports an evaluation of immediate post-placental insertion of a non-copper (Lippes Loop D) and several copper-bearing IUD models (TCu200, TCu220C, MLCu375, MLCu250, Nova T-PP, DimélysR). Based on the analysis of a total of 2,646 insertions and 55,794 woman-months of experience, we conclude that placement of an IUD within ten minutes of delivery of the placenta is a valuable alternative to interval insertion, because this method is safe and effective. Effectiveness was significantly lower for the Lippes Loop D than for the T- and ML-IUD models tested, the latter showing roughly comparable pertinent event rates. Pertinent event rates for copper IUDs were influenced by the skill of the operator; age of the recipient only had a significant effect on effectiveness, whereas parity had no significant effect on pertinent event rates. The single and still unsolved problem associated with immediate postpartum insertion is the greater likelihood of expulsion compared with interval insertion, and this hazard is significantly much greater for the Loop than for the copper-bearing devices assessed. The evolution of the expulsion rates shows a constant time-relationship. This pattern makes it obvious why follow-up of recipients, at least during the first trimester following insertion, is mandatory if immediate post-placental IUD insertion is to be optimally effective. PMID:4006467

  4. Knot Insertion Algorithms for ECT B-spline Curves

    Institute of Scientific and Technical Information of China (English)

    SONG Huan-huan; TANG Yue-hong; LI Yu-juan

    2013-01-01

    Knot insertion algorithm is one of the most important technologies of B-spline method. By inserting a knot the local prop-erties of B-spline curve and the control flexibility of its shape can be further improved, also the segmentation of the curve can be re-alized. ECT spline curve is drew by the multi-knots spline curve with associated matrix in ECT spline space;Muehlbach G and Tang Y and many others have deduced the existence and uniqueness of the ECT spline function and developed many of its important properties .This paper mainly focuses on the knot insertion algorithm of ECT B-spline curve.It is the widest popularization of B-spline Behm algorithm and theory. Inspired by the Behm algorithm, in the ECT spline space, structure of generalized Pólya poly-nomials and generalized de Boor Fix dual functional, expressing new control points which are inserted after the knot by linear com-bination of original control vertex the single knot, and there are two cases, one is the single knot, the other is the double knot. Then finally comes the insertion algorithm of ECT spline curve knot. By application of the knot insertion algorithm, this paper also gives out the knot insertion algorithm of four order geometric continuous piecewise polynomial B-spline and algebraic trigonometric spline B-spline, which is consistent with previous results.

  5. Role of Chitinase 3-Like-1 in Interleukin-18-Induced Pulmonary Type 1, Type 2, and Type 17 Inflammation; Alveolar Destruction; and Airway Fibrosis in the Murine Lung.

    Science.gov (United States)

    Kang, Min-Jong; Yoon, Chang Min; Nam, Milang; Kim, Do-Hyun; Choi, Je-Min; Lee, Chun Geun; Elias, Jack A

    2015-12-01

    Chitinase 3-like 1 (Chi3l1), which is also called YKL-40 in humans and BRP-39 in mice, is the prototypic chitinase-like protein. Recent studies have highlighted its impressive ability to regulate the nature of tissue inflammation and the magnitude of tissue injury and fibroproliferative repair. This can be appreciated in studies that highlight its induction after cigarette smoke exposure, during which it inhibits alveolar destruction and the genesis of pulmonary emphysema. IL-18 is also known to be induced and activated by cigarette smoke, and, in murine models, the IL-18 pathway has been shown to be necessary and sufficient to generate chronic obstructive pulmonary disease-like inflammation, fibrosis, and tissue destruction. However, the relationship between Chi3l1 and IL-18 has not been defined. To address this issue we characterized the expression of Chi3l1/BRP-39 in control and lung-targeted IL-18 transgenic mice. We also characterized the effects of transgenic IL-18 in mice with wild-type and null Chi3l1 loci. The former studies demonstrated that IL-18 is a potent stimulator of Chi3l1/BRP-39 and that this stimulation is mediated via IFN-γ-, IL-13-, and IL-17A-dependent mechanisms. The latter studies demonstrated that, in the absence of Chi3l1/BRP-39, IL-18 induced type 2 and type 17 inflammation and fibrotic airway remodeling were significantly ameliorated, whereas type 1 inflammation, emphysematous alveolar destruction, and the expression of cytotoxic T lymphocyte perforin, granzyme, and retinoic acid early transcript 1 expression were enhanced. These studies demonstrate that IL-18 is a potent stimulator of Chi3l1 and that Chi3l1 is an important mediator of IL-18-induced inflammatory, fibrotic, alveolar remodeling, and cytotoxic responses.

  6. Development of ITER toroidal field insert. International collaboration with Russia

    International Nuclear Information System (INIS)

    The Central Solenoid (CS) model coil programme was performed since 1992 as one of the projects in the Engineering Design Activity (EDA) of the International Thermonuclear Experimental Reactor(ITER). The CS model coil programme involves a plan to develop the Toroidal Field (TF) insert to demonstrate the conductor performance of ITER TF coils under a magnetic flux density of 13T. The TF insert was fabricated by Russia and tested by Japan under the framework of the ITER-EDA. The TF insert developed a single-layer solenoid with nine turns. It is wound with a cable-in-conduit (CIC) conductor which consists of 1,152 Nb3Sn strands, a thin titanium jacket and a central channel. The outer diameter, height and weight of the TF insert are 1.56 m, 3.2 m and 3.1 ton, respectively. Fabrication of the TF insert was completed in May 2001 at the D.V.Efremov Scientific Research Institute for Electrophysical Apparatus (Efremov institute) in St. Petersburg, Russia. The TF insert was then transported to the Japan Atomic Energy Research Institute (JAERI). Installation of the TF insert to CS model coil test facility was completed in August, 2001. Experiments including the cooldown and warmup processes, were completed in November 2001. The TF insert was charged to 13T with 46 kA without any instability under a back up magnetic field from the CS model coil. This report introduces an overview of the fabrication, installation and experiments for the TF insert conducted under collaboration between Japan and Russia. (author)

  7. Islet amyloid polypeptide inserts into phospholipid monolayers as monomer.

    Science.gov (United States)

    Engel, Maarten F M; Yigittop, HaciAli; Elgersma, Ronald C; Rijkers, Dirk T S; Liskamp, Rob M J; de Kruijff, Ben; Höppener, Jo W M; Antoinette Killian, J

    2006-02-24

    Amyloid deposits in the pancreatic islets of Langerhans are thought to be a main factor responsible for death of the insulin-producing islet beta-cells in type 2 diabetes. It is hypothesized that beta-cell death is related to interaction of the 37 amino acid residue human islet amyloid polypeptide (hIAPP), the major constituent of islet amyloid, with cellular membranes. However, the mechanism of hIAPP-membrane interactions is largely unknown. Here, we study the nature and the molecular details of the initial step of hIAPP-membrane interactions by using the monolayer technique. It is shown that both freshly dissolved hIAPP and the non-amyloidogenic mouse IAPP (mIAPP) have a pronounced ability to insert into phospholipid monolayers, even at lipid packing conditions that exceed the conditions that occur in biological membranes. In contrast, the fibrillar form of hIAPP has lost the ability to insert. These results, combined with the observations that both the insertion kinetics and the dependence of insertion on the initial surface pressure are similar for freshly dissolved hIAPP and mIAPP, indicate that hIAPP inserts into phospholipid monolayers most likely as a monomer. In addition, our results suggest that the N-terminal part of hIAPP, which is nearly identical with that of mIAPP, is largely responsible for insertion. This is supported by experiments with hIAPP fragments, which show that a peptide consisting of the 19 N-terminal residues of hIAPP efficiently inserts into phospholipid monolayers, whereas an amyloidogenic decapeptide, consisting of residues 20-29 of hIAPP, inserts much less efficiently. The results obtained here suggest that hIAPP monomers might insert with high efficiency in biological membranes in vivo. This process could play an important role as a first step in hIAPP-induced membrane damage in type 2 diabetes. PMID:16403520

  8. Catalytic X-H insertion reactions based on carbenoids.

    Science.gov (United States)

    Gillingham, Dennis; Fei, Na

    2013-06-21

    Catalysed X-H insertion reactions into diazo compounds (where X is any heteroatom) are a powerful yet underutilized class of transformations. The following review will explore the historical development of X-H insertion and give an up-to-date account of the metal catalysts most often employed, including an assessment of their strengths and weaknesses. Despite decades of development, recent work on enantioselective variants, as well as applying catalytic X-H insertion towards problems in chemical biology indicate that this field has ample room for innovation. PMID:23407887

  9. Study on Visually Design of Indexable Insert Tip

    Institute of Scientific and Technical Information of China (English)

    YAO Ji-quan; ZHAO Shu-qiang; ZHANG Shen-hou; CHEN Xin; GUO Xian-yang

    2013-01-01

    In order to improve the development efficiency of the indexable insert tip, three-dimensional parametric and visualization applications program of indexable insert tip was developed in AutoCAD VBA (Visual Basic for Applications). The software could significantly improve the modeling efficiency of indexable insert tip and the model could also be used to static analysis, dynamic analysis and thermodynamic analysis. All aspects of performance could be fully understood by the finite element analysis. The ref-erence for the blade parameters preferred is also provided.

  10. Cutting inserts effect on heat generation in turning process

    Directory of Open Access Journals (Sweden)

    Ján Žitňanský

    2014-03-01

    Full Text Available The paper is focused on confirmation of an effect of cutting materials and cutting inserts geometry on cutting forces and temperature, quality and accuracy of machined surface in turning. The main part is devoted to description of advanced turning tools and cutting materials. The experimental part is focused on cutting forces and temperature measurement and machined surface quality in turning of steel grade 11 523 samples with one feed and depth of cut value and varying spindle speed. Measurements were performed with various types of indexable cutting inserts used. Measured values were evaluated in terms of the effect of different properties of cutting inserts and various spindle speed values.

  11. Industrial stator vane with sequential impingement cooling inserts

    Science.gov (United States)

    Jones, Russell B; Fedock, John A; Goebel, Gloria E; Krueger, Judson J; Rawlings, Christopher K; Memmen, Robert L

    2013-08-06

    A turbine stator vane for an industrial engine, the vane having two impingement cooling inserts that produce a series of impingement cooling from the pressure side to the suction side of the vane walls. Each insert includes a spar with a row of alternating impingement cooling channels and return air channels extending in a radial direction. Impingement cooling plates cover the two sides of the insert and having rows of impingement cooling holes aligned with the impingement cooling channels and return air openings aligned with the return air channel.

  12. International Workshop on Magnetic Measurements of Insertion Devices

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The International Workshop on Magnetic Measurements of Insertion Devices was held at the Advanced Photon Source, Argonne National Laboratory, on September 28--29, 1993. The workshop brought together scientists and engineers from Europe, Japan, and the United States to discuss the following topics: Special techniques for magnetic measurements of insertion devices, magnetic tolerances of the insertion devices for third generation synchrotron radiation sources, methods for and accuracy of the multipole moments measurements, magnetic sensors, among other topics. The workshop included thirteen presentations that are collected in this volume.

  13. Diamagnetic (Condon) domains

    International Nuclear Information System (INIS)

    This paper is the first systematic review of experimental research on diamagnetic (aka Condon) domains that form in nonmagnetic metals at low temperatures due to the development of Landau levels. A variety of methods were used to study the domains. Muon spectroscopy studies showed such domains to be present in all metals studied, pointing to the universal nature of the phenomenon. For silver, the domain structure size as measured by Hall microsensors turned out to be an order of magnitude larger than expected. In beryllium, it was found that domains do not come to the surface but rather remain in the bulk of the crystal. The magnetostriction of beryllium during domain formation is measured. It is shown that magnetization current in a domain wall is entirely caused by the charge density gradient in the wall, due to the lattice being deformed oppositely in neighboring domains. It is observed for the first time that the de Haas-van Alphen effect exhibits hysteresis at the transition to the domain state, and this fact was used for the experimental determination of the phase diagrams for the domain states of silver and beryllium. (reviews of topical problems)

  14. 黄蓝状菌几丁质酶E2纯化、性质及抗菌活性研究%Purification,properties and antifungal activity of one chitinase produeced by Talaromyces flavus

    Institute of Scientific and Technical Information of China (English)

    陈述; 王志伟; 解文科; 唐帅; 李慧

    2011-01-01

    黄蓝状菌在SMCS液体培养基中置于恒温摇床(200r/min,27.5C)上培养13天,诱导产生大量的几丁质酶。培养滤液经硫酸铵分级沉淀,DEAE--Sepharose FastFlow阴离子交换层析、Phenyl—Sepharose Fast Flow疏水层析、Sephacryl S-100分子筛层析得到了凝胶电泳(SDS—PAGE)谱带单一的几丁质酶E2,其分子量为32KD。其最适反应温度为50℃,最适pH值是5。Mn^2+对其有明显的激活作用,Cu^2+、FeCu^2+对其有强烈的抑制作用。抗菌活性显示.其对供试病原菌具有明显的抑菌作用。%One extracellular chitinase E, was purified to SDS--PAGE homogeneous by ammonium sulfate fraction, DEAE Sepharose Fast Flow Chromatography, Phenyl-Sepharose Fast Flow Chromatography and Sephacryl S- 100 charomatogra phy when Talaromyces fiavus was grown in SMCS broth at 27.5℃ on a rotary shaker at 200r/min for 13 days. The molecular weight of the chitinase was about 32kD. The property and antifungal activity of chitinase were tested in tbis study,the results were as the followings:The optimal pH and temperature of the enzyme for hydrolysis of chitin are 5 and at 50℃ respectively. Different metal ions showed different effects on the chitinase activities, Mn2+ evidently increased activity of the chitinases, Na+,Ca2+ and K+ increased partially activitiy of the chitinase , whereasCu2-, FeCu2+ caused inhibition heavily. Thechitinases appeared to be antifungal activity against tested fungi and more effective against fungi of Fusarium oxysporum Schlecht, Botryosphaeria berengeriana f. sp. Piricola Alternaria logipes and Verticillium dahliae.

  15. 黏质沙雷氏菌C8-8几丁质酶基因的克隆与表达%Cloning and expression of a chitinase gene from Serratia marcescens strain C8-8

    Institute of Scientific and Technical Information of China (English)

    刘邮洲; 罗楚平; 刘永锋; 陈志谊

    2012-01-01

    利用PCR方法从黏质沙雷氏菌(Serratia marcescens)C8-8中克隆到编码几丁质酶的chiA基因,大小为1692bp,推测其编码一条长563个氨基酸的多肽链,分子量约为60900.同源分析研究结果表明从C8-8中克隆的chiA基因序列与黏质沙雷氏菌株141(DQ990373.1)和14041菌株(DQ493896.1)的chiA基因序列相似性最高,达到99%.结构域分析结果表明从C8-8中克隆的chiA基因N末端(23AA)存在典型的信号肽序列,C端存在另外两个结构域,即PKD区(73AA)和几丁质酶催化区(387AA).采用大肠杆菌表达系统重组表达chiA基因,结果表明重组菌株在几丁质诱导培养基上能产生透明的水解圈.采用SDS-PAGE电泳分析,结果表明chiA重组表达产物的相对分子质量约为60000,与预测分子量大小基本一致.初步提纯后,生物活性试验结果表明该重组表达产物能水解几丁质,在几丁质培养基上产生透明的水解圈.%An open reading frame encoding chiA gene was cloned from the Serratia marcescens strain C8-8 genomic DNA by PCR, with the length of 1 692 bp. Its sequence was 99% identical with chiA sequences of Serratia marcescens 141 and 14041. Domain analysis showed that the cloned chiA gene involved a typical signal peptide sequence at N-terraination (23 AA), and PKD domain (73 AA) and chitinase catalytic domain (387 AA) at C-termination. The PCR fragment was digested and cloned into plasmid pET28a to construct plasmid pET28a-ChiA, which was then transformed into expression host Escherichia. coli DH3. The recombined strain DH3 ChiA could yield transparent hydrolyzed zone on the colloidal chi-tin plate induced by isopropyl-1 -thiogalactopyranoside (IPTG). A protein with molecular weight about 60 000 was expressed by DH3 ChiA, and could also yield a hydrolyzed rone on the colloidal chitin plate. It indicated that chiA gene from C8-8 could be utilized as a potential biological factor for control of fungi.

  16. The use of dimorphic Alu insertions in human DNA fingerprinting

    Energy Technology Data Exchange (ETDEWEB)

    Novick, G.E.; Gonzalez, T.; Garrison, J.; Novick, C.C.; Herrera, R.J. [Florida International Univ., Miami, FL (United States). Dept. of Biological Sciences; Batzer, M.A. [Lawrence Livermore National Lab., CA (United States); Deininger, P.L. [Louisiana State Univ., New Orleans, LA (United States). Medical Center

    1992-12-04

    We have characterized certain Human Specific Alu Insertions as either dimorphic (TPA25, PV92, APO), sightly dimorphic (C2N4 and C4N4) or monomorphic (C3N1, C4N6, C4N2, C4N5, C4N8), based on studies of Caucasian, Asian, American Black and African Black populations. Our approach is based upon: (1) PCR amplification using primers directed to the sequences that flank the site of insertion of the different Alu elements studied; (2) gel electrophoresis and scoring according to the presence or absence of an Alu insertion in one or both homologous chromosomes; (3) allelic frequencies calculated and compared according to Hardy-Weinberg equilibrium. Our DNA fingerprinting procedure using PCR amplification of dimorphic Human Specific Alu insertions, is stable enough to be used not only as a tool for genetic mapping but also to characterize populations, study migrational patterns and track the inheritance of human genetic disorders.

  17. A new insertion sequence for incremental Delaunay triangulation

    Institute of Scientific and Technical Information of China (English)

    Jian-Fei Liu; Jin-Hui Yan; S.H.Lo

    2013-01-01

    Incremental algorithm is one of the most popular procedures for constructing Delaunay triangulations (DTs).However,the point insertion sequence has a great impact on the amount of work needed for the construction of DTs.It affects the time for both point location and structure update,and hence the overall computational time of the triangulation algorithm.In this paper,a simple deterministic insertion sequence is proposed based on the breadth-first-search on a Kd-tree with some minor modifications for better performance.Using parent nodes as search-hints,the proposed insertion sequence proves to be faster and more stable than the Hilbert curve order and biased randomized insertion order (BRIO),especially for non-uniform point distributions over a wide range of benchmark examples.

  18. Bougie insertion: A common practice with underestimated dangers

    Science.gov (United States)

    Theodorou, D.; Doulami, G.; Larentzakis, A.; Almpanopoulos, K.; Stamou, K.; Zografos, G.; Menenakos, E.

    2011-01-01

    Introduction Esophageal perforation after bariatric operations is rare. We report two cases of esophageal perforation after bariatric operations indicating the dangers of a common practice – like insertion of esophageal tubes – and we describe our management of that complication. Presentation of case A 56 year old woman who underwent laparoscopic sleeve gastrectomy and a 41 year old woman who underwent laparoscopic adjustable gastric banding respectively. In both operations a bougie has been used and led to esophageal perforation. Discussion The insertion of bougie and especially of inflated bougie is a common practice. It is an invasive procedure that in most cases is performed by the anesthesiologist team. Conclusion Bougie insertion is an invasive procedure with risks and should always be attempted under direct supervision of surgical team or should be inserted by a surgeon. PMID:22288051

  19. Fireplace insert and its parameters depend on the used glazing

    Science.gov (United States)

    Papučík, Štefan; Čaja, Alexander

    2016-06-01

    The contribution deals with the analysis of the impact of using double glass to change the performance and emission parameters of the fireplace insert. Conventional fireplace inserts are equipped with heat-resistant glass, which is resistant to high temperatures. For this type of inserts are required to be radiant constituent maximized. Prevailing part of heat is into the interior gets just by radiation through the glazed part. The hot water fireplace inserts is the requirement that the radiant constituent to the environment to a minimum. Therefore, instead of a single glass using double glazing which is intended to reduce this part of heat transfer. The temperature in the furnace is increased, and transmitted most of the heat into the water.

  20. Visualizing latent domain knowledge

    OpenAIRE

    Chen, C.; Kuljis, J; Paul, RJ

    2001-01-01

    Knowledge discovery and data mining commonly rely on finding salient patterns of association from a vast amount of data. Traditional citation analysis of scientific literature draws insights from strong citation patterns. Latent domain knowledge, in contrast to the mainstream domain knowledge, often consists of highly relevant but relatively infrequently cited scientific works. Visualizing latent domain knowledge presents a significant challenge to knowledge discovery and quantitative studies...

  1. Frustratingly Easy Domain Adaptation

    CERN Document Server

    Daumé, Hal

    2009-01-01

    We describe an approach to domain adaptation that is appropriate exactly in the case when one has enough ``target'' data to do slightly better than just using only ``source'' data. Our approach is incredibly simple, easy to implement as a preprocessing step (10 lines of Perl!) and outperforms state-of-the-art approaches on a range of datasets. Moreover, it is trivially extended to a multi-domain adaptation problem, where one has data from a variety of different domains.

  2. Staggered domain wall fermions

    CERN Document Server

    Hoelbling, Christian

    2016-01-01

    We construct domain wall fermions with a staggered kernel and investigate their spectral and chiral properties numerically in the Schwinger model. In some relevant cases we see an improvement of chirality by more than an order of magnitude as compared to usual domain wall fermions. Moreover, we present first results for four-dimensional quantum chromodynamics, where we also observe significant reductions of chiral symmetry violations for staggered domain wall fermions.

  3. Pragmatic circuits frequency domain

    CERN Document Server

    Eccles, William

    2006-01-01

    Pragmatic Circuits: Frequency Domain goes through the Laplace transform to get from the time domain to topics that include the s-plane, Bode diagrams, and the sinusoidal steady state. This second of three volumes ends with a-c power, which, although it is just a special case of the sinusoidal steady state, is an important topic with unique techniques and terminology. Pragmatic Circuits: Frequency Domain is focused on the frequency domain. In other words, time will no longer be the independent variable in our analysis. The two other volumes in the Pragmatic Circuits series include titles on DC

  4. Needle Insertion with Duty-Cycled Rotation into Multiple Media

    OpenAIRE

    Lehocky, Craig A.; Riviere, Cameron N.

    2012-01-01

    Thin, flexible needles can be steered along nonlinear paths to reach deep anatomical structures within the human body. This study builds upon previous work involving steering of bevel-tipped needles by inserting while rotating in a duty-cycled fashion. Here we investigate how needle material and radius, duty cycle, and tissue stiffness affect needle curvature. Needles were inserted into media while rotated at a specified duty cycle and the curvature was measured. A linear relationship between...

  5. Heat Transfer Enhancement by Using Different Types of Inserts

    OpenAIRE

    Tabatabaeikia, S.; Mohammed, H.A.; Nik-Ghazali, N.; Shahizare, B.

    2014-01-01

    Heat transfer enhancement has been always a significantly interesting topic in order to develop high efficient, low cost, light weight, and small heat exchangers. The energy cost and environmental issue are also encouraging researchers to achieve better performance than the existing designs. Two of the most effective ways to achieve higher heat transfer rate in heat exchangers are using different kinds of inserts and modifying the heat exchanger tubes. There are different kinds of inserts emp...

  6. Insertion and Deletion Processes in Recent Human History

    OpenAIRE

    Per Sjödin; Thomas Bataillon; Schierup, Mikkel H.

    2010-01-01

    BACKGROUND: Although insertions and deletions (indels) account for a sizable portion of genetic changes within and among species, they have received little attention because they are difficult to type, are alignment dependent and their underlying mutational process is poorly understood. A fundamental question in this respect is whether insertions and deletions are governed by similar or different processes and, if so, what these differences are. METHODOLOGY/PRINCIPAL FINDINGS: We use publishe...

  7. Generating Novel Allelic Variation Through Activator Insertional Mutagenesis in Maize

    OpenAIRE

    Bai, Ling; Singh, Manjit; Pitt, Lauren; Sweeney, Meredith; Brutnell, Thomas P.

    2007-01-01

    The maize transposable element Activator (Ac) has been exploited as an insertional mutagen to disrupt, clone, and characterize genes in a number of plant species. To develop an Ac-based mutagenesis platform for maize, a large-scale mutagenesis was conducted targeting the pink scutellum1 locus. We selected 1092 Ac transposition events from a closely linked donor Ac, resulting in the recovery of 17 novel ps1 alleles. Multiple phenotypic classes were identified corresponding to Ac insertions in ...

  8. Lithium Insertion In Silicon Nanowires: An ab Initio Study

    KAUST Repository

    Zhang, Qianfan

    2010-09-08

    The ultrahigh specific lithium ion storage capacity of Si nanowires (SiNWs) has been demonstrated recently and has opened up exciting opportunities for energy storage. However, a systematic theoretical study on lithium insertion in SiNWs remains a challenge, and as a result, understanding of the fundamental interaction and microscopic dynamics during lithium insertion is still lacking. This paper focuses on the study of single Li atom insertion into SiNWs with different sizes and axis orientations by using full ab initio calculations. We show that the binding energy of interstitial Li increases as the SiNW diameter grows. The binding energies at different insertion sites, which can be classified as surface, intermediate, and core sites, are quite different. We find that surface sites are energetically the most favorable insertion positions and that intermediate sites are the most unfavorable insertion positions. Compared with the other growth directions, the [110] SiNWs with different diameters always present the highest binding energies on various insertion locations, which indicates that [110] SiNWs are more favorable by Li doping. Furthermore, we study Li diffusion inside SiNWs. The results show that the Li surface diffusion has a much higher chance to occur than the surface to core diffusion, which is consistent with the experimental observation that the Li insertion in SiNWs is layer by layer from surface to inner region. After overcoming a large barrier crossing surface-to-intermediate region, the diffusion toward center has a higher possibility to occur than the inverse process. © 2010 American Chemical Society.

  9. Blind bedside insertion of small bowel feeding tubes.

    LENUS (Irish Health Repository)

    Duggan, SN

    2009-12-01

    The use of Naso-Jejunal (NJ) feeding is limited by difficulty in feeding tube placement. Patients have traditionally required transfer to Endoscopy or Radiology for insertion of small bowel feeding tubes, with clear resource implications. We hypothesised that the adoption of a simple bedside procedure would be effective and reduce cost. Clinical nutrition and nurse specialist personnel were trained in the 10\\/10\\/10 method of blind bedside NJ insertion.

  10. A new specifically designed forceps for chest drain insertion.

    LENUS (Irish Health Repository)

    Andrews, Emmet

    2012-02-03

    Insertion of a chest drain can be associated with serious complications. It is recommended that the drain is inserted with blunt dissection through the chest wall but there is no specific instrument to aid this task. We describe a new reusable forceps that has been designed specifically to facilitate the insertion of chest drains.A feasibility study of its use in patients who required a chest drain as part of elective cardiothoracic operations was undertaken. The primary end-point was successful and accurate placement of the drain. The operators also completed a questionnaire rating defined aspects of the procedure. The new instrument was used to insert the chest drain in 30 patients (19 male, 11 female; median age 61.5 years (range 16-81 years)). The drain was inserted successfully without the trocar in all cases and there were no complications. Use of the instrument rated as significantly easier relative to experience of previous techniques in all specified aspects. The new device can be used to insert intercostal chest drains safely and efficiently without using the trocar or any other instrument.

  11. Modeling Amyloid Beta Peptide Insertion into Lipid Bilayers

    CERN Document Server

    Mobley, D L; Singh, R R P; Maddox, M W; Longo, M J; Mobley, David L.; Cox, Daniel L.; Singh, Rajiv R. P.; Maddox, Michael W.; Longo, Marjorie L.

    2003-01-01

    Inspired by recent suggestions that the Alzheimer's amyloid beta peptide (A-beta), can insert into cell membranes and form harmful ion channels, we model insertion of the peptide into cell membranes using a Monte Carlo code which is specific at the amino acid level. We examine insertion of the regular A-beta peptide as well as mutants causing familial Alzheimer's disease. We present our results and develop the hypothesis that partial insertion into the membrane, leaving the peptide in one leaflet, increases the probability of harmful channel formation. This hypothesis can partly explain why these mutations are neurotoxic simply due to peptide insertion behavior, and also explains why, normally, A-beta 42 is more toxic to some cultured cells than A-beta 40, but the E22Q mutation reverses this effect. We further apply this model to various artificial A-beta mutants which have been examined experimentally, and offer testable experimental predictions contrasting the roles of aggregation and insertion with regard ...

  12. A dosimetric comparison of copper and Cerrobend electron inserts.

    Science.gov (United States)

    Rusk, Benjamin D; Carver, Robert L; Gibbons, John P; Hogstrom, Kenneth R

    2016-01-01

    The purpose of this work was to evaluate differences in dose resulting from the use of copper aperture inserts compared to lead-alloy (Cerrobend) aperture inserts for electron beam therapy. Specifically, this study examines if copper aperture inserts can be used clinically with the same commissioning data measured using lead-alloy aperture inserts. The copper inserts were acquired from .decimal, LLC and matching lead-alloy, Cerrobend inserts were constructed in-house for 32 com-binations of nine square insert field sizes (2 × 2 to 20 × 20 cm2) and five applicator sizes (6 × 6 to 25 × 25 cm2). Percent depth-dose and off-axis relative dose profiles were measured using an electron diode in water for select copper and Cerrobend inserts for a subset of applicators (6 × 6, 10 × 10, 25 × 25 cm2) and energies (6, 12, 20 MeV) at 100 and 110 cm source-to-surface distances (SSD) on a Varian Clinac 21EX accelerator. Dose outputs were measured for all field size-insert combina-tions and five available energies (6-20 MeV) at 100 cm SSD and for a smaller subset at 110 cm SSD. Using these data, 2D planar absolute dose distributions were generated and compared. Criteria for agreement were ± 2% of maximum dose or 1 mm distance-to-agreement for 99% of points. A gamma analysis of the beam dosimetry showed 94 of 96 combinations of insert size, applicator, energy, and SSD were within the 2%/1 mm criteria for > 99% of points. Outside the field, copper inserts showed less bremsstrahlung dose under the insert compared to Cerrobend (greatest difference was 2.5% at 20 MeV and 100 cm SSD). This effect was most prominent at the highest energies for combinations of large applicators with small field sizes, causing some gamma analysis failures. Inside the field, more electrons scattered from the collimator edge of copper compared to Cerrobend, resulting in an increased dose at the field edge for copper at shallow depths (greatest increase was 1% at 20 MeV and 100 cm SSD). Dose

  13. Unassisted translocation of large polypeptide domains across phospholipid bilayers

    OpenAIRE

    Brambillasca, Silvia; Yabal, Monica; Makarow, Marja; Borgese, Nica

    2006-01-01

    Although transmembrane proteins generally require membrane-embedded machinery for integration, a few can insert spontaneously into liposomes. Previously, we established that the tail-anchored (TA) protein cytochrome b(5) (b5) can posttranslationally translocate 28 residues downstream to its transmembrane domain (TMD) across protein-free bilayers (Brambillasca, S., M. Yabal, P. Soffientini, S. Stefanovic, M. Makarow, R.S. Hegde, and N. Borgese. 2005. EMBO J. 24:2533–2542). In the present study...

  14. Topological Domain Theory

    OpenAIRE

    Battenfeld, Ingo

    2008-01-01

    This thesis presents Topological Domain Theory as a powerful and flexible framework for denotational semantics. Topological Domain Theory models a wide range of type constructions and can interpret many computational features. Furthermore, it has close connections to established frameworks for denotational semantics, as well as to well-studied mathematical theories, such as topology and computable analysis.

  15. Modeling Protein Domain Function

    Science.gov (United States)

    Baker, William P.; Jones, Carleton "Buck"; Hull, Elizabeth

    2007-01-01

    This simple but effective laboratory exercise helps students understand the concept of protein domain function. They use foam beads, Styrofoam craft balls, and pipe cleaners to explore how domains within protein active sites interact to form a functional protein. The activity allows students to gain content mastery and an understanding of the…

  16. Studies on the Screening of Chitinase Producing Strain from Ocean and Its Optimization on Fermentation%海洋产几丁质酶菌株的筛选及发酵条件优化

    Institute of Scientific and Technical Information of China (English)

    张灿; 黄德智; 李丰硕; 王硕; 薛永常

    2012-01-01

    A strain with high productivity of chitinase was screened through transparent circle method from sea mud of Dalian seaside and was identified as species Brevibacterium linens. After medium optimization and orthogonal experiments, which include carbon sources, nitrogen sources, temperature and pH, the chitinase activity was improved. The results showed that the optimized conditions for chitinase production were 1 g/L peptone, 10 g/L Colloidal chitin, the NaCl of 20 g/L, culture at 28 ?and pH 7.0. Under these conditions the chitinase activity can reach 0.508 U/mL,9 times higher than that of par ent strain.%通过透明圈法初筛、DNS复筛,从大连近海海域的海泥中分离出一株高产几丁质酶的菌株,经初步鉴定为扩展短杆菌(Brevibacterium linens).采用不同碳源、氮源、温度、pH值等对培养条件进行了优化及正交试验.结果表明:该菌产酶最适条件是在28℃、pH7.0、蛋白胨1g/L、胶体几丁质10g/L、NaCl 20g/L条件下,几丁质酶活力可达0.508 U/mL,比优化前其产酶活力提高了9倍.

  17. Urethral catheter insertion forces: a comparison of experience and training

    Directory of Open Access Journals (Sweden)

    Benjamin K. Canales

    2009-02-01

    Full Text Available Purpose: This study was undertaken to evaluate the insertion forces utilized during simulated placement of a urethral catheter by healthcare individuals with a variety of catheter experience. Materials and Methods: A 21F urethral catheter was mounted to a metal spring. Participants were asked to press the tubing spring against a force gauge and stop when they met a level of resistance that would typically make them terminate a catheter placement. Simulated catheter insertion was repeated fives times, and peak compression forces were recorded. Healthcare professionals were divided into six groups according to their title: urology staff, non-urology staff, urology resident/ fellow, non-urology resident/ fellow, medical student, and registered nurse. Results: A total of fifty-seven healthcare professionals participated in the study. Urology staff (n = 6 had the lowest average insertion force for any group at 6.8 ± 2.0 Newtons (N. Medical students (n = 10 had the least amount of experience (1 ± 0 years and the highest average insertion force range of 10.1 ± 3.7 N. Health care workers with greater than 25 years experience used significantly less force during catheter insertions (4.9 ± 1.8 N compared to all groups (p < 0.01. Conclusions: We propose the maximum force that should be utilized during urethral catheter insertion is 5 Newtons. This force deserves validation in a larger population and should be considered when designing urethral catheters or creating catheter simulators. Understanding urethral catheter insertion forces may also aid in establishing competency parameters for health care professionals in training.

  18. 枯草芽孢杆菌SL-13的生防性能及其抗菌几丁质酶特性研究%Biocontrol Efficiency of Bacillus subtilis SL-13 and Characterization of an Antifungal Chitinase

    Institute of Scientific and Technical Information of China (English)

    刘燕; 陶晶; 阎豫君; 李彬; 李晖; 李春

    2011-01-01

    The seed germination and tomato seedling tests showed that Bacillus subtilis SL-13 could promote the sprouting and seedling growth of tomato. The fresh and dry weight of tomato seedlings increased 42.86% and 18.75%, respectively. The control efficacies of the SL-13 to tomato Rhizoctonia rot were 20.65% and 35.23% in the greenhouse and field, respectively. The growth of the plant-pathogenic fungus Rhizoctonia solani was considerably inhibited in the presence of the strain SL-13 culture supernatant. The main antifungal protein was detected to be chitinase through vitro assay. The chitinase was purified with DEAE-Sepharose fast flow ion exchange column chromatography and Sephadex G-75 gel filtration for further characterization. The optimal pH and temperature for the chitinase activity were 7.0 and 50 ℃, respectively. It was demonstrated that the enzyme was stable at pH 5-9 and 40-60 ℃. 70% of the enzyme activity was retained when incubated at 121 ℃ and 0.11 MPa for 20 min, and the enzyme was not sensitive to protease K and ultraviolet radiation. Thus it is suitable for effective biological control in relatively unstable environment.

  19. The SAH domain extends the functional length of the myosin lever

    OpenAIRE

    Baboolal, TG; Sakamoto, T.; Forgacs, E; White, HD; Jackson, SM; Takagi, Y.; Farrow, RE; Molloy, JE; Knight, PJ; Sellers, JS; Peckham, M.

    2009-01-01

    Stable, single alpha-helix (SAH) domains are widely distributed in the proteome, including in myosins, but their functions are unknown. To test whether SAH domains can act as levers, we replaced four of the six calmodulin-binding IQ motifs in the levers of mouse myosin 5a (Myo5) with the putative SAH domain of Dictyostelium myosin MyoM of similar length. The SAH domain was inserted between the IQ motifs and the coiled coil in a Myo5 HMM construct in which the levers were truncated from six to...

  20. Seamless lesion insertion in digital mammography: methodology and reader study

    Science.gov (United States)

    Pezeshk, Aria; Petrick, Nicholas; Sahiner, Berkman

    2016-03-01

    Collection of large repositories of clinical images containing verified cancer locations is costly and time consuming due to difficulties associated with both the accumulation of data and establishment of the ground truth. This problem poses a significant challenge to the development of machine learning algorithms that require large amounts of data to properly train and avoid overfitting. In this paper we expand the methods in our previous publications by making several modifications that significantly increase the speed of our insertion algorithms, thereby allowing them to be used for inserting lesions that are much larger in size. These algorithms have been incorporated into an image composition tool that we have made publicly available. This tool allows users to modify or supplement existing datasets by seamlessly inserting a real breast mass or micro-calcification cluster extracted from a source digital mammogram into a different location on another mammogram. We demonstrate examples of the performance of this tool on clinical cases taken from the University of South Florida Digital Database for Screening Mammography (DDSM). Finally, we report the results of a reader study evaluating the realism of inserted lesions compared to clinical lesions. Analysis of the radiologist scores in the study using receiver operating characteristic (ROC) methodology indicates that inserted lesions cannot be reliably distinguished from clinical lesions.

  1. Customizable engineered blood vessels using 3D printed inserts.

    Science.gov (United States)

    Pinnock, Cameron B; Meier, Elizabeth M; Joshi, Neeraj N; Wu, Bin; Lam, Mai T

    2016-04-15

    Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment. PMID:26732049

  2. Customizable engineered blood vessels using 3D printed inserts.

    Science.gov (United States)

    Pinnock, Cameron B; Meier, Elizabeth M; Joshi, Neeraj N; Wu, Bin; Lam, Mai T

    2016-04-15

    Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment.

  3. Recombination of an intrachromosomal paracentric insertion of chromosome 3

    Energy Technology Data Exchange (ETDEWEB)

    Best, R.G.; Burnett, W.J.; Brock, J.K. [Univ. of South Carolina School of Medicine, Columbia, SC (United States)] [and others

    1994-09-01

    Cytogenetic studies were initiated on a newborn female due to multiple congenital anomalies including microcephaly, clinodactyly, abnormal positioning of hands, left facial palsy, heart defect, sacral dimple, and facial dysmorphic features. Facial features were described as low set rotated ears, nystagmus, and a small, flattened nose. A structural rearrangement of the long arm of chromosome 3 was observed with a complex banding pattern. Study of parental chromosomes revealed a normal male pattern for the father, and an intrachromosomal insertion on the long arm of chromosome 3 for the mother described as 46,XX,dir ins(3)(q21q23q26.2). Further characterization of the proband`s structurally abnormal chromosome 3 revealed a karyotype best described as: 46,XX,rec(3),dupq23{r_arrow}q26.2::q21{r_arrow}q23,dir ins(3)(q21q23q26.2), which is a partial duplication of both the inserted segment as well as the intervening segment between the inserted segment and the insertion site. This would appear to be the result of a three-strand double cross-over within the insertion loop. Molecular cytogenetic studies are presently underway to further elucidate chromosome structure of the proband and her mother.

  4. Minimizing of the only-insertion insdel systems

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A more recent branch of natural computing is DNA computing. At the theoretical level, DNA computing is powerful.This is due to the fact that DNA structure and processing suggest a series of new data structures and operations, and to the fact of the massive parallelism. The insertion-deletion system (insdel system) is a DNA computing model based on two genetic operations:insertion and deletion which, working together, are very powerful, leading to characterizations of recursively enumerable languages. When designing an insdel computer, it is natural to try to keep the underlying model as simple as possible. One idea is to use either only insertion operations or only deletion operations. By helping with a weak coding and a morphism, the family INS47DEL00 is equal to the family of recursively enumerable languages. It is an open problem proposed by Martin-Vide et al. on whether or not the parameters 4 and 7 appearing here can be replaced by smaller numbers. In this paper, our positive answer to this question is that INS42DEL00 can also play the same role as insertion and deletion. We suppose that the INS42DEL00 may be the least only-insertion insdel system in this situation. We will give some reasons supporting this conjecture in our paper.

  5. Silver clusters insert into polymer solar cell for enhancing light absorption

    Institute of Scientific and Technical Information of China (English)

    Guolong Li; Hongyu Zhen; Zhuoyin Huang; Kan Li; Weidong Shen; Xu Liu

    2012-01-01

    As an employment of surface plasmonic effect,the consequence of insertion of a layer of Ag clusters into polymer solar cell on the enhancement of light absorption and power conversion efficiency is investigated.Optical analysis based on the finite-difference time-domain (FDTD) is performed with experiments to evaluate the effect of the interaction between the Ag clusters and incident light on light absorption in polymer solar cell Ag clusters modify the light wave vector and the electromagnetic field inside the device is redistributed and enhanced.As a result,polymer solar cells achieve an overall increase in absorption,short-circuit current density,and power conversion efficiency.

  6. Isolation of sequences flanking Ac insertion sites by Ac casting.

    Science.gov (United States)

    Wang, Dafang; Peterson, Thomas

    2013-01-01

    Localizing Ac insertions is a fundamental task in studying Ac-induced mutation and chromosomal rearrangements involving Ac elements. Researchers may sometimes be faced with the situation in which the sequence flanking one side of an Ac/Ds element is known, but the other flank is unknown. Or, a researcher may have a small sequence surrounding the Ac/Ds insertion site and needs to obtain additional flanking genomic sequences. One way to rapidly clone unknown Ac/Ds flanking sequences is via a PCR-based method termed Ac casting. This approach utilizes the somatic transposition activity of Ac during plant development, and provides an efficient means for short-range genome walking. Here we describe the principle of Ac casting, and show how it can be applied to isolate Ac macrotransposon insertion sites.

  7. THEORETICAL ANALYSIS ON THE DEPTH OF NEEDLE-INSERTION

    Institute of Scientific and Technical Information of China (English)

    LIN Wen-jian

    2005-01-01

    In the present paper, the author sums up and analyzes descriptions about needle-insertion depth in Chinese classical medical book Huang Di Nei Jing (The Yellow Emperor's Internal Classic). In many chapters of Nei Jing, the needle-insertion depth is stressed to be various according to 1) the deficiency or excess of syndromes, 2) the patients' constitution, 3) the severity of disease, 4) the duration of disease, 5) the location of disease, 6) the patient's age, 7) the location of the needled acupoint, 8) the season, 9) the patient's temperament, 10) the pulse condition, 11) the state of "Deqi", and 12) the location of the running course of meridians. In addition, different kinds of diseases and different stages of diseases also need different depths of needle insertion, different manipulating skills and different stimulating quantity.

  8. The strategic use of inserts in the Brazilian presidential elections

    Directory of Open Access Journals (Sweden)

    Felipe Borba

    2012-01-01

    Full Text Available The aim of this article is to analyze the communication strategies of presidential candidates during the elections held in 2006 and 2010. The focus is on the strategic component of electoral inserts and the methodology consists of investigating how candidates choose to distribute these inserts in the programming of television networks. The results indicate that the candidates pursue different strategies influenced basically by three variables: electoral legislation, their standing in polls and the difference of resources available. In parallel, the article debates the role of the regulation of electoral advertising and how this set of rules influences the level of information of campaigns, the occurrence of attacks, and party strategies. Overall, 2,993 electoral inserts were examined.

  9. Reliable communication over non-binary insertion/deletion channels

    CERN Document Server

    Yazdani, Raman

    2012-01-01

    We consider the problem of reliable communication over non-binary insertion/deletion channels where symbols are randomly deleted from or inserted in the transmitted sequence and all symbols are corrupted by additive white Gaussian noise. To this end, we utilize the inherent redundancy achievable in non-binary symbol sets by first expanding the symbol set and then allocating part of the bits associated with each symbol to watermark symbols. The watermark sequence, known at the receiver, is then used by a forward-backward algorithm to provide soft information for an outer code which decodes the transmitted sequence. Through numerical results and discussions, we evaluate the performance of the proposed solution and show that it leads to significant system ability to detect and correct insertions/deletions. We also provide estimates of the maximum achievable information rates of the system, compare them with the available bounds, and construct practical codes capable of approaching these limits.

  10. Electrochemical insertion of lithium into polyacrylonitrile-based disordered carbons

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Y.; Suh, M.C.; Lee, S.I.; Shim, S.C.; Kwak, J. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Chemistry; Lee, H.; Kim, M. [Korea Research Inst. of Standards and Science, Taejon (Korea, Republic of). Div. of Chemistry and Radiation

    1997-12-01

    Electrochemical lithium insertion into polyacrylonitrile (PAN)-based disordered carbons was studied using the techniques of discharge/charge tests, cyclic voltammetry, and {sup 7}Li nuclear magnetic resonance (NMR) spectroscopy. The PAN-based carbons were prepared by vacuum pyrolysis of PAN at 500, 800, and 1,000 C. They showed charge capacities between 254 and 380 mAh/g in the first cycle. {sup 7}Li NMR spectra showed two kinds of lithium insertion sites in the PAN-based carbons: a reversible site where lithium is removed in the subsequent charge process and an irreversible site where lithium remains intact. The NMR results suggest that lithium in fully Li-inserted PAN-based carbons has an ionic character, and reversible site lithium resides between negatively charged carbon layers.

  11. Quantum chemical study on insertion and abstraction reaction of dichlorocarbene with methyl alcohol and methyl mercaptan

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-Feng; ZHU Yuan-Cheng; LI Hui-Xue; LIU Xin-Wen; LU Xiao-Quan

    2009-01-01

    The Insertion and abstraction reaction mechanisms of singlet and triplet CCl2 with CH3MH (M=O, S) have been studied by using the DFT, NBO and AIM methods. The geometries of reactions, the transition state and products were completely optimized by B3LYP/6-311G(d, p). All the energy of the species was obtained at the CCSD(T)/6-311G(d, p) level. The calculated results indicated that the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCl2 can not only trigger the insertion reaction with C-H and M-H in four pathways, by which the products P1 [CH3OCHCl2, reaction I (1)], P3[Cl2HCCH2OH, reaction Ⅰ(2)], PS[CH3SCHCl2, reaction Ⅱ(1)] and P7[Cl2HCCH2SH, reac-tion Ⅱ(2)] are produced respectively, but also abstract M-H, resulting P4 [CH2O+CH2Cl2, reaction Ⅰ(3)] and PS[CH2S+CH2Cl2, reaction Ⅱ (3)]. In addition, the important geometries in domain pathways have been studied by AIM and NBO theories.

  12. Transposable element insertions in long intergenic non-coding RNA genes

    Directory of Open Access Journals (Sweden)

    Sivakumar eKannan

    2015-06-01

    Full Text Available Transposable elements (TE are abundant in mammalian genomes and appear to have contributed to the evolution of their hosts by providing novel regulatory or coding sequences. We analyzed different regions of long intergenic non-coding RNA (lincRNA genes in human and mouse genomes to systematically assess the potential contribution of TEs to the evolution of the structure and regulation of expression of lincRNA genes. Introns of lincRNA genes contain the highest percentage of TE-derived sequences, followed by exons and then promoter regions although the density of TEs is not significantly different between exons and promoters. Higher frequencies of ancient TEs in promoters and exons compared to introns implies that many lincRNA genes emerged before the split of primates and rodents. The content of TE-derived sequences in lincRNA genes is substantially higher than that in protein-coding genes, especially in exons and promoter regions. A significant positive correlation was detected between the content of TEs and evolutionary rate of lincRNAs indicating that inserted TEs are preferentially fixed in fast-evolving lincRNA genes. These results are consistent with the RIDL (Repeat Insertion Domains of LncRNAs hypothesis under which TEs have substantially contributed to the origin, evolution, and in particular functional diversification, of lincRNA genes.

  13. How to insert a nasogastric tube and check gastric position at the bedside.

    Science.gov (United States)

    Best, Carolyn

    2016-05-18

    Rationale and key points A nasogastric tube (NG tube) can be used to aspirate stomach contents or to administer feed, medication or fluid into the stomach. ▶ A blind technique is used to insert the NG tube through the nostril, along the nasopharynx, through the oesophagus and into the stomach. ▶ It is important for nurses to be able to recognise problems that may arise when inserting a NG tube blindly, and to know what actions to take if it is suspected that the distal tip of the NG tube is not sitting in the stomach, or they are unable to identify its location. ▶ Misplacement and subsequent use of a NG tube to administer feed, medication or fluid is a 'never event' ( NHS England Patient Safety Domain 2015 ). Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How you think this article will change your practice. 2. How you could use this resource to educate your colleagues. Subscribers can update their reflective accounts at rcni.com/portfolio. PMID:27191450

  14. Quantum chemical study on insertion and abstraction reaction of dichlorocarbene with methyl alcohol and methyl mercaptan

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The insertion and abstraction reaction mechanisms of singlet and triplet CCl2 with CH3MH (M=O, S) have been studied by using the DFT, NBO and AIM methods. The geometries of reactions, the transition state and products were completely optimized by B3LYP/6-311G(d, p). All the energy of the species was obtained at the CCSD(T)/6-311G(d, p) level. The calculated results indicated that the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCl2 can not only trigger the insertion reaction with C-H and M-H in four pathways, by which the products P1 [CH3OCHCl2, reactionⅠ(1)], P3[Cl2HCCH2OH, reactionⅠ(2)], P5[CH3SCHCl2, reactionⅡ(1)] and P7[Cl2HCCH2SH, reac-tion Ⅱ(2)] are produced respectively, but also abstract M-H, resulting P4 [CH2O+CH2Cl2, reactionⅠ(3)] and P8[CH2S+CH2Cl2, reactionⅡ(3)]. In addition, the important geometries in domain pathways have been studied by AIM and NBO theories.

  15. How to insert a nasogastric tube and check gastric position at the bedside.

    Science.gov (United States)

    Best, Carolyn

    2016-05-18

    Rationale and key points A nasogastric tube (NG tube) can be used to aspirate stomach contents or to administer feed, medication or fluid into the stomach. ▶ A blind technique is used to insert the NG tube through the nostril, along the nasopharynx, through the oesophagus and into the stomach. ▶ It is important for nurses to be able to recognise problems that may arise when inserting a NG tube blindly, and to know what actions to take if it is suspected that the distal tip of the NG tube is not sitting in the stomach, or they are unable to identify its location. ▶ Misplacement and subsequent use of a NG tube to administer feed, medication or fluid is a 'never event' ( NHS England Patient Safety Domain 2015 ). Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How you think this article will change your practice. 2. How you could use this resource to educate your colleagues. Subscribers can update their reflective accounts at rcni.com/portfolio.

  16. Genetic Analysis of MEFV Gene Pyrin Domain in Patients With Behçet's Disease

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Objectives. Behçet's disease (BD is a systemic vasculitis with recurrent oral and genital ulcers and uveitis. MEFV gene, which is the main factor in familial Mediterranean fever (FMF, is also reported to be a susceptibility gene for BD. The pyrin domain of MEFV gene is a member of death-domain superfamily and has been proposed to regulate inflammatory signaling in myeloid cells. This study was designed to determine if mutations in pyrin domain of MEFV gene are involved in BD. Methods. We analyzed the pyrin domain of MEFV gene in 54 Turkish patients with BD by PCR-analysis and direct sequencing. Results. Neither deletion or insertion mutations nor point mutations in pyrin domain were found in any patient. Conclusion. Although pyrin gene mutations have been reported in patients with BD, pyrin domain is not mutated. However, alterations in other regions of MEFV gene and interaction between pyrin domains are needed to be further investigated.

  17. Conserved Domain Database (CDD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — CDD is a protein annotation resource that consists of a collection of well-annotated multiple sequence alignment models for ancient domains and full-length proteins.

  18. Effect of Light Conducting Cylindrical Inserts on Gingival Microleakage

    Directory of Open Access Journals (Sweden)

    SM. Moazzami

    2007-03-01

    Full Text Available Objective: Microleakage in the gingival floor of class II composite restorations can compromise the marginal adaptation of the filling material to the cavity edges. The aim of this study was to evaluate the effect of light conducting cylindrical inserts in decreasing the microleakage of the gingival floor in cavities 1mm below the CEJ.Materials and Methods: Eighty maxillary first molars were randomly divided into eight groups according to use of glass inserts, type of resin (Coltene unfilled resin versus Scotchbond multi purpose and filling technique (one-unit versus incremental. Proximal class II cavities were prepared in all samples with the gingival floor one millimeter below the CEJ. Etched and silan-treated glass inserts were made from 2mm cylindrical bioglass material and cavities were restored according to research protocol. The samples were subjected to 2500 thermal cycles (5-55oC, immersed in 0.5% basic fuchsin solution, embedded in epoxy resin and cut centrally and laterally (buccally or lingually in a mesiodistal direction. Microleakage was scored and collected data were statistically analyzed using Kruskal-Wallis and Mann-Whitney tests.Results: Minimal dye penetration was observed in the group that employed the incre-mental technique along with Scotchbond, with or without glass inserts. A significant difference was observed between the eight groups. In addition the use of the incremental technique and glass inserts had a significant effect on the microleakage of lateral and central sections, respectively. Application of dentin bonding agent signifi-cantly affected both sections.Conclusion: Glass inserts were effective in decreasing cervical microleakage of class II cavities restored with composite resin.

  19. Magnetic ripple correction in tandem mirrors by ferromagnetic inserts

    International Nuclear Information System (INIS)

    Magnetic ripple of 1% or more caused by discrete solenoid coils in the central cells of tandem mirrors may severely affect the MHD stability. The ripple amplitude can be reduced by an order of magnitude by ferromagnetic annuli inserted within the coils at the regions of ripple maxima. The inserts need not affect the accessibility, coil diameter, or capital cost, since large quantities of steel are required within the coils for the neutron blanket and shield. Design of the ripple correction is simplified and linearized by the cylindrical geometry and by the saturation of the ferromagnetic steel

  20. Insertion of lithium into electrochromic devices after completion

    Energy Technology Data Exchange (ETDEWEB)

    Berland, Brian Spencer; Lanning, Bruce Roy; Frey, Jonathan Mack; Barrett, Kathryn Suzanne; DuPont, Paul Damon; Schaller, Ronald William

    2015-12-22

    The present disclosure describes methods of inserting lithium into an electrochromic device after completion. In the disclosed methods, an ideal amount of lithium can be added post-fabrication to maximize or tailor the free lithium ion density of a layer or the coloration range of a device. Embodiments are directed towards a method to insert lithium into the main device layers of an electrochromic device as a post-processing step after the device has been manufactured. In an embodiment, the methods described are designed to maximize the coloration range while compensating for blind charge loss.

  1. Tension Pneumothorax and Subcutaneous Emphysema Complicating Insertion of Nasogastric Tube.

    Science.gov (United States)

    Al Saif, Narjis; Hammodi, Adel; Al-Azem, M Ali; Al-Hubail, Rasheed

    2015-01-01

    Nasogastric tube has a key role in the management of substantial number of hospitalized patients particularly the critically ill. In spite of the apparent simple insertion technique, nasogastric tube placement has its serious perhaps fatal complications which need to be carefully assessed. Pulmonary misplacement and associated complications are commonplace during nasogastric tube procedure. We present a case of tension pneumothorax and massive surgical emphysema in critically ill ventilated patient due to inadvertent nasogastric tube insertion and also discussed the risk factors, complication list, and arrays of techniques for safer tube placement.

  2. Rectal fist insertion. An unusual form of sexual behavior.

    Science.gov (United States)

    Shook, L L; Whittle, R; Rose, E F

    1985-12-01

    Rectal fist insertion (fist fucking) is an uncommon and potentially dangerous sexual practice. This is usually a homosexual activity, but can also be a heterosexual or an autoerotic practice. One known death has been reported associated with rectal fist insertion, in which the complications of anal and colonic tears and bleeding had occurred (see Editor's note). The possibility of drug overdose is also probable, as drugs and alcohol are commonly introduced into the rectum to promote sphincter relaxation and to ease the discomfort of anal dilatation. PMID:4072987

  3. Imaging of the complications of peripherally inserted central venous catheters

    Energy Technology Data Exchange (ETDEWEB)

    Amerasekera, S.S.H. [Department of Radiology, Good Hope Hospital, Sutton Coldfield, Birmingham (United Kingdom)], E-mail: steve.amerasekera@nhs.net; Jones, C.M.; Patel, R.; Cleasby, M.J. [Department of Radiology, Good Hope Hospital, Sutton Coldfield, Birmingham (United Kingdom)

    2009-08-15

    Peripherally inserted central catheters (PICC) are widely used to provide central venous access, often in chronically ill patients with long-term intravenous access requirements. There are a number of significant complications related to both insertion and maintenance of PICC lines, including catheter malposition, migration, venous thrombosis, and line fracture. The incidence of these complications is likely to rise as the number of patients undergoing intravenous outpatient therapy increases, with a corresponding rise in radiologist input. This paper provides an overview of the relevant peripheral and central venous anatomy, including anatomical variations, and outlines the complications of PICC lines. Imaging examples demonstrate the range of radiological findings seen in these complications.

  4. Advanced photon source experience with vacuum chambers for insertion devices

    International Nuclear Information System (INIS)

    During the last five years, a new approach to the design and fabrication of extruded aluminum vacuum chambers for insertion devices was developed at the Advanced Photon Source (APS). With this approach, three different versions of the vacuum chamber, with vertical apertures of 12 mm, 8 mm, and 5 mm, were manufactured and tested. Twenty chambers were installed into the APS vacuum system. All have operated with beam, and 16 have been coupled with insertion devices. Two different vacuum chambers with vertical apertures of 16 mm and 11 mm were developed for the BESSY-II storage ring and 3 of 16 mm chambers were manufactured

  5. Shield Insertion to Minimize Noise Amplitude in Global Interconnects

    Directory of Open Access Journals (Sweden)

    Kalpana.A.B

    2012-09-01

    Full Text Available Shield insertion is an effective technique for minimise crosstalk noise and signal delay uncertainty .To reduce the effects of coupling uniform or simultaneous shielding may be used on either or both sides of a signal line. Shields are ground or power lines placed between two signal wires to prevent direct coupling between them as the shield width increases, the noise amplitude decreases, in this paper inserting a shield line between two coupled interconnects is shown to be more effective in reducing crosstalk noise for different technology nodes .

  6. Tension Pneumothorax and Subcutaneous Emphysema Complicating Insertion of Nasogastric Tube

    Directory of Open Access Journals (Sweden)

    Narjis AL Saif

    2015-01-01

    Full Text Available Nasogastric tube has a key role in the management of substantial number of hospitalized patients particularly the critically ill. In spite of the apparent simple insertion technique, nasogastric tube placement has its serious perhaps fatal complications which need to be carefully assessed. Pulmonary misplacement and associated complications are commonplace during nasogastric tube procedure. We present a case of tension pneumothorax and massive surgical emphysema in critically ill ventilated patient due to inadvertent nasogastric tube insertion and also discussed the risk factors, complication list, and arrays of techniques for safer tube placement.

  7. Ultrasonic airborne insertion loss measurements at normal incidence (L).

    Science.gov (United States)

    Farley, Jayrin; Anderson, Brian E

    2010-12-01

    Transmission loss and insertion loss measurements of building materials at audible frequencies are commonly made using plane wave tubes or as a panel between reverberant rooms. These measurements provide information for noise isolation control in architectural acoustics and in product development. Airborne ultrasonic sound transmission through common building materials has not been fully explored. Technologies and products that utilize ultrasonic frequencies are becoming increasingly more common, hence the need to conduct such measurements. This letter presents preliminary measurements of the ultrasonic insertion loss levels for common building materials over a frequency range of 28-90 kHz using continuous-wave excitation. PMID:21218864

  8. Sequences determining the cytoplasmic localization of a chemoreceptor domain.

    Science.gov (United States)

    Seligman, L; Bailey, J; Manoil, C

    1995-01-01

    The Escherichia coli serine chemoreceptor (Tsr) is a protein with a simple topology consisting of two membrane-spanning sequences (TM1 and TM2) separating a large periplasmic domain from N-terminal and C-terminal cytoplasmic regions. We analyzed the contributions of several sequence elements to the cytoplasmic localization of the C-terminal domain by using chemoreceptor-alkaline phosphatase gene fusions. The principal findings were as follows. (i) The cytoplasmic localization of the C-terminal domain depended on TM2 but was quite tolerant of mutations partially deleting or introducing charged residues into the sequence. (ii) The basal level of C-terminal domain export was significantly higher in proteins with the wild-type periplasmic domain than in derivatives with a shortened periplasmic domain, suggesting that the large size of the wild-type domain promotes partial membrane misinsertion. (iii) The membrane insertion of deletion derivatives with a single spanning segment (TM1 or TM2) could be controlled by either an adjacent positively charged sequence or an adjacent amphipathic sequence. The results provide evidence that the generation of the Tsr membrane topology is an overdetermined process directed by an interplay of sequences promoting and opposing establishment of the normal structure. PMID:7730259

  9. The supermodule insertion tool of the CMS electromagnetic calorimeter and the first trial insertion of a supermodule.

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The first trial insertion of a complete Electromagnetic Calorimeter (ECAL) "supermodule" (1700 lead-tungstate crystals, with support structures, light detectors (avalanche photodiodes), readout electronics and cooling system) was performed on 1st March. This delicate operation - sliding a 2-tonne 3m-long object onto support rails (in real life these are attached to the barrel hadron calorimeter (HCAL)) - made use of a custom designed "squirrel cage". The rotatable squirrel cage allows the insertion of any supermodule into any of the 18 positions, including very fine (sub-mm) adjustments. The first supermodule will be inserted into the real HCAL later this month in preparation for the "magnet test and cosmic-ray challenge" (MTCC). In the first image the supermodule is in the centre and the alignment disks are highlighted by the flash.

  10. Chitinase-resistant hydrophilic symbiotic factors secreted by Frankia activate both Ca(2+) spiking and NIN gene expression in the actinorhizal plant Casuarina glauca.

    Science.gov (United States)

    Chabaud, Mireille; Gherbi, Hassen; Pirolles, Elodie; Vaissayre, Virginie; Fournier, Joëlle; Moukouanga, Daniel; Franche, Claudine; Bogusz, Didier; Tisa, Louis S; Barker, David G; Svistoonoff, Sergio

    2016-01-01

    Although it is now well-established that decorated lipo-chitooligosaccharide Nod factors are the key rhizobial signals which initiate infection/nodulation in host legume species, the identity of the equivalent microbial signaling molecules in the Frankia/actinorhizal association remains elusive. With the objective of identifying Frankia symbiotic factors we present a novel approach based on both molecular and cellular pre-infection reporters expressed in the model actinorhizal species Casuarina glauca. By introducing the nuclear-localized cameleon Nup-YC2.1 into Casuarina glauca we show that cell-free culture supernatants of the compatible Frankia CcI3 strain are able to elicit sustained high frequency Ca(2+) spiking in host root hairs. Furthermore, an excellent correlation exists between the triggering of nuclear Ca(2+) spiking and the transcriptional activation of the ProCgNIN:GFP reporter as a function of the Frankia strain tested. These two pre-infection symbiotic responses have been used in combination to show that the signal molecules present in the Frankia CcI3 supernatant are hydrophilic, of low molecular weight and resistant to chitinase degradation. In conclusion, the biologically active symbiotic signals secreted by Frankia appear to be chemically distinct from the currently known chitin-based rhizobial/arbuscular mycorrhizal signaling molecules. Convenient bioassays in Casuarina glauca are now available for their full characterization. PMID:26484850

  11. C-reactive protein and chitinase 3-like protein 1 as biomarkers of spatial redistribution of retinal blood vessels on digital retinal photography in patients with diabetic retinopathy.

    Science.gov (United States)

    Cekić, Sonja; Cvetković, Tatjana; Jovanović, Ivan; Jovanović, Predrag; Pesić, Milica; Stanković Babić, Gordana; Milenković, Svetislav; Risimić, Dijana

    2014-08-20

    The aim of the study was to investigate the correlation between the levels of C-reactive protein (CRP) and chitinase 3-like protein 1 (YKL-40) in blood samples with morpohometric parameters of retinal blood vessels in patients with diabetic retinopathy. Blood laboratory examination of 90 patients included the measurement of glycemia, HbA1C, total cholesterol, LDL-C, HDL-C, triglycerides and CRP. Levels of YKL-40 were detected and measured in serum by ELISA (Micro VueYKL-40 EIA Kit, Quidel Corporation, San Diego, USA). YKL-40 correlated positively with diameter and negatively with number of retinal blood vessels. The average number of the blood vessels per retinal zone was significantly higher in the group of patients with mild non-proliferative diabetic retinopathy than in the group with severe form in the optic disc and all five retinal zones. The average outer diameter of the evaluated retinal zones and optic disc vessels was significantly higher in the group with severe compared to the group with mild diabetic retinopathy. Morphological analysis of the retinal vessels on digital fundus photography and correlation with YKL-40 may be valuable for the follow-up of diabetic retinopathy.

  12. Chitinase 3-like 1 expression by human (MG63) osteoblasts in response to lysophosphatidic acid and 1,25-dihydroxyvitamin D3.

    Science.gov (United States)

    Mansell, J P; Cooke, M; Read, M; Rudd, H; Shiel, A I; Wilkins, K; Manso, M

    2016-01-01

    Chitinase 3-like 1, otherwise known as YKL-40, is a secreted glycoprotein purported to have a role in extracellular matrix metabolism. The first mammalian cell type found to express YKL-40 was the human osteosarcoma-derived osteoblast, MG63. In that first study the active vitamin D3 metabolite, 1,25-dihydroxycholecalciferol (1,25D), stimulated YKL-40 expression, thereby indicating that a vital factor for skeletal health promoted YKL-40 synthesis by bone forming cells. However, when these MG63 cells were exposed to 1,25D they were also exposed to serum, a rich source of the pleiotropic lipid mediator, lysophosphatidic acid (LPA). Given that 1,25D is now known to co-operate with selected growth factors, including LPA, to influence human osteoblast differentiation we hypothesised that 1,25D and LPA may work together to stimulate osteoblast YKL-40 expression. Herein we report that 1,25D and LPA synergistically promote YKL-40 expression by MG63 cells. Inhibitors targeting AP1, MEK, Sp1 and STAT3 blunted the expression of both alkaline phosphatase and YKL-40 by MG63 cells in response to co-stimulation with 1,25D and LPA. Other ligands of the vitamin D receptor also co-operated with LPA in driving YKL-40 mobilisation. Collectively our findings highlight another important role of 1,25D and LPA in the regulation of human osteoblast function. PMID:27575987

  13. Domains in Ferroelectric Nanostructures

    Science.gov (United States)

    Gregg, Marty

    2010-03-01

    Ferroelectric materials have great potential in influencing the future of small scale electronics. At a basic level, this is because ferroelectric surfaces are charged, and so interact strongly with charge-carrying metals and semiconductors - the building blocks for all electronic systems. Since the electrical polarity of the ferroelectric can be reversed, surfaces can both attract and repel charges in nearby materials, and can thereby exert complete control over both charge distribution and movement. It should be no surprise, therefore, that microelectronics industries have already looked very seriously at harnessing ferroelectric materials in a variety of applications, from solid state memory chips (FeRAMs) to field effect transistors (FeFETs). In all such applications, switching the direction of the polarity of the ferroelectric is a key aspect of functional behavior. The mechanism for switching involves the field-induced nucleation and growth of domains. Domain coarsening, through domain wall propagation, eventually causes the entire ferroelectric to switch its polar direction. It is thus the existence and behavior of domains that determine the switching response, and ultimately the performance of the ferroelectric device. A major issue, associated with the integration of ferroelectrics into microelectronic devices, has been that the fundamental properties associated with ferroelectrics, when in bulk form, appear to change quite dramatically and unpredictably when at the nanoscale: new modes of behaviour, and different functional characteristics from those seen in bulk appear. For domains, in particular, the proximity of surfaces and boundaries have a dramatic effect: surface tension and depolarizing fields both serve to increase the equilibrium density of domains, such that minor changes in scale or morphology can have major ramifications for domain redistribution. Given the importance of domains in dictating the overall switching characteristics of a device

  14. How does the Shift-insertion sort behave when the sorting elements follow a Normal distribution?

    CERN Document Server

    Pal, Mita; Mahanti, N C

    2012-01-01

    The present paper examines the behavior of Shift-insertion sort (insertion sort with shifting) for normal distribution inputs and is in continuation of our earlier work on this new algorithm for discrete distribution inputs, namely, negative binomial. Shift insertion sort is found more sensitive for main effects but not for all interaction effects compared to conventional insertion sort.

  15. Observations on rotating needle insertions using a brachytherapy robot

    Energy Technology Data Exchange (ETDEWEB)

    Meltsner, M A [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States); Ferrier, N J [Department of Mechanical Engineering, University of Wisconsin, Madison, WI 53706 (United States); Thomadsen, B R [Department of Medical Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2007-09-21

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  16. Observations on rotating needle insertions using a brachytherapy robot

    Science.gov (United States)

    Meltsner, M. A.; Ferrier, N. J.; Thomadsen, B. R.

    2007-09-01

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  17. Effects of Rotational Motion in Robotic Needle Insertion

    Science.gov (United States)

    Ramezanpour, H.; Yousefi, H.; Rezaei, M.; Rostami, M.

    2015-01-01

    Background Robotic needle insertion in biological tissues has been known as one the most applicable procedures in sampling, robotic injection and different medical therapies and operations. Objective In this paper, we would like to investigate the effects of angular velocity in soft tissue insertion procedure by considering force-displacement diagram. Non-homogenous camel liver can be exploited as a tissue sample under standard compression test with Zwick/Roell device employing 1-D axial load-cell. Methods Effects of rotational motion were studied by running needle insertion experiments in 5, 50 and 200 mm/min in two types of with or without rotational velocity of 50, 150 and 300 rpm. On further steps with deeper penetrations, friction force of the insertion procedure in needle shaft was acquired by a definite thickness of the tissue. Results Designed mechanism of fixture for providing different frequencies of rotational motion is available in this work. Results for comparison of different force graphs were also provided. Conclusion Derived force-displacement graphs showed a significant difference between two procedures; however, tissue bleeding and disorganized micro-structure would be among unavoidable results. PMID:26688800

  18. Prototype ISR Superconducting Quadrupole for the low beta insertion.

    CERN Multimedia

    1976-01-01

    The four coils are provisionally kept together by aluminium clamps while epoxy-glass bands are wrapped around them to form a number of spacer rings.Stainless steel spacers were then inserted between these rings and the yoke quadrants. The persons are Michel Bouvier(left) and Pierre Pugin. See also7702690X.

  19. Surgical insertion of transmitters and telemetry methods in fisheries research

    DEFF Research Database (Denmark)

    Rub, A. Michelle Wargo; Jepsen, Niels; Liedtke, Theresa L.;

    2014-01-01

    ) will be described. Effects of surgical insertion of transmitters (ie, tagging) and aspects of the surgical implantation process where collaboration and professional exchanges among nonveterinarian researchers and veterinarians may be most fruitful will be discussed. Although this report focuses on surgical...

  20. Computer Modeling of Protocellular Functions: Peptide Insertion in Membranes

    Science.gov (United States)

    Rodriquez-Gomez, D.; Darve, E.; Pohorille, A.

    2006-01-01

    Lipid vesicles became the precursors to protocells by acquiring the capabilities needed to survive and reproduce. These include transport of ions, nutrients and waste products across cell walls and capture of energy and its conversion into a chemically usable form. In modem organisms these functions are carried out by membrane-bound proteins (about 30% of the genome codes for this kind of proteins). A number of properties of alpha-helical peptides suggest that their associations are excellent candidates for protobiological precursors of proteins. In particular, some simple a-helical peptides can aggregate spontaneously and form functional channels. This process can be described conceptually by a three-step thermodynamic cycle: 1 - folding of helices at the water-membrane interface, 2 - helix insertion into the lipid bilayer and 3 - specific interactions of these helices that result in functional tertiary structures. Although a crucial step, helix insertion has not been adequately studied because of the insolubility and aggregation of hydrophobic peptides. In this work, we use computer simulation methods (Molecular Dynamics) to characterize the energetics of helix insertion and we discuss its importance in an evolutionary context. Specifically, helices could self-assemble only if their interactions were sufficiently strong to compensate the unfavorable Free Energy of insertion of individual helices into membranes, providing a selection mechanism for protobiological evolution.

  1. Folding and insertion thermodynamics of the transmembrane WALP peptide.

    Science.gov (United States)

    Bereau, Tristan; Bennett, W F Drew; Pfaendtner, Jim; Deserno, Markus; Karttunen, Mikko

    2015-12-28

    The anchor of most integral membrane proteins consists of one or several helices spanning the lipid bilayer. The WALP peptide, GWW(LA)n (L)WWA, is a common model helix to study the fundamentals of protein insertion and folding, as well as helix-helix association in the membrane. Its structural properties have been illuminated in a large number of experimental and simulation studies. In this combined coarse-grained and atomistic simulation study, we probe the thermodynamics of a single WALP peptide, focusing on both the insertion across the water-membrane interface, as well as folding in both water and a membrane. The potential of mean force characterizing the peptide's insertion into the membrane shows qualitatively similar behavior across peptides and three force fields. However, the Martini force field exhibits a pronounced secondary minimum for an adsorbed interfacial state, which may even become the global minimum-in contrast to both atomistic simulations and the alternative PLUM force field. Even though the two coarse-grained models reproduce the free energy of insertion of individual amino acids side chains, they both underestimate its corresponding value for the full peptide (as compared with atomistic simulations), hinting at cooperative physics beyond the residue level. Folding of WALP in the two environments indicates the helix as the most stable structure, though with different relative stabilities and chain-length dependence.

  2. Effects of lithium insertion on thermal conductivity of silicon nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Wen [Department of Physics, Centre for Advanced 2D Material and Centre for Computational Science and Engineering, National University of Singapore, Singapore, Singapore 117546 (Singapore); Institute of High Performance Computing, A*STAR, Singapore, Singapore 138632 (Singapore); Zhang, Gang, E-mail: zhangg@ihpc.a-star.edu.sg [Institute of High Performance Computing, A*STAR, Singapore, Singapore 138632 (Singapore); Li, Baowen [Department of Physics, Centre for Advanced 2D Material and Centre for Computational Science and Engineering, National University of Singapore, Singapore, Singapore 117546 (Singapore); NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Kent Ridge, Singapore 119620 (Singapore); Center for Phononics and Thermal Energy Science, School of Physics Science and Engineering, Tongji University, 200092 Shanghai (China)

    2015-04-27

    Recently, silicon nanowires (SiNWs) have been applied as high-performance Li battery anodes, since they can overcome the pulverization and mechanical fracture during lithiation. Although thermal stability is one of the most important parameters that determine safety of Li batteries, thermal conductivity of SiNWs with Li insertion remains unclear. In this letter, using molecular dynamics simulations, we study room temperature thermal conductivity of SiNWs with Li insertion. It is found that compared with the pristine SiNW, there is as much as 60% reduction in thermal conductivity with 10% concentration of inserted Li atoms, while under the same impurity concentration the reduction in thermal conductivity of the mass-disordered SiNW is only 30%. With lattice dynamics calculations and normal mode decomposition, it is revealed that the phonon lifetimes in SiNWs decrease greatly due to strong scattering of phonons by vibrational modes of Li atoms, especially for those high frequency phonons. The observed strong phonon scattering phenomenon in Li-inserted SiNWs is similar to the phonon rattling effect. Our study serves as an exploration of thermal properties of SiNWs as Li battery anodes or weakly coupled with impurity atoms.

  3. Root cause of incomplete control rod insertions at Westinghouse reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ray, S. [Westinghouse, Monroeville, PA (United States)

    1997-01-01

    Within the past year, incomplete RCCA insertions have been observed on high burnup fuel assemblies at two Westinghouse PWRs. Initial tests at the Wolf Creek site indicated that the direct cause of the incomplete insertions observed at Wolf Creek was excessive fuel assembly thimble tube distortion. Westinghouse committed to the NRC to perform a root cause analysis by the end of August, 1996. The root cause analysis process used by Westinghouse included testing at ten sites to obtain drag, growth and other characteristics of high burnup fuel assemblies. It also included testing at the Westinghouse hot cell of two of the Wolf Creek incomplete insertion assemblies. A mechanical model was developed to calculate the response of fuel assemblies when subjected to compressive loads. Detailed manufacturing reviews were conducted to determine if this was a manufacturing related issue. In addition, a review of available worldwide experience was performed. Based on the above, it was concluded that the thimble tube distortion observed on the Wolf Creek incomplete insertion assemblies was caused by unusual fuel assembly growth over and above what would typically be expected as a result of irradiation exposure. It was determined that the unusual growth component is a combination of growth due to oxide accumulation and accelerated growth, and would only be expected in high temperature plants on fuel assemblies that see long residence times and high power duties.

  4. Insertional mutagenesis using Tnt1 retrotransposon in potato

    Science.gov (United States)

    Potato is the third most important food crop in the world. However, genetics and genomics research of potato has lagged behind many major crop species due to its autotetraploidy and a highly heterogeneous genome. Insertional mutagenesis using T-DNA or transposable elements, which is available in sev...

  5. Eustachian tube function in children after insertion of ventilation tubes.

    NARCIS (Netherlands)

    Heerbeek, N. van; Ingels, K.J.A.O.; Snik, A.F.M.; Zielhuis, G.A.

    2001-01-01

    This study was performed to assess the effect of the insertion of ventilation tubes and the subsequent aeration of the middle ear on eustachian tube (ET) function in children. Manometric ET function tests were performed repeatedly for 3 months after the placement of ventilation tubes in 83 children

  6. Insertion Success of the Laryngeal Tube in Emergency Airway Management

    Science.gov (United States)

    Gries, André; Ramshorn-Zimmer, Alexandra; Wenzel, Volker

    2016-01-01

    Background. Emergency airway management (AM) is a priority when resuscitating critically ill or severely injured patients. The goal of this study was to determine the success rates of LT insertion during AM. Methods. Studies that included LT first-pass insertion (FPI) and overall-pass insertion (OPI) success by emergency medical services and in-hospital providers performing AM for emergency situations as well as for scheduled surgery published until July 2014 were searched systematically in Medline. Results. Data of 36 studies (n = 1,897) reported a LT FPI success by physicians of 82.5% with an OPI success of 93.6% (p < 0.001). A cumulative analysis of all 53 studies (n = 3,600) led to FPI and OPI success of 80.1% and 92.6% (p < 0.001), respectively. The results of 26 studies (n = 2,159) comparing the LT with the laryngeal mask airway (LMA) demonstrated a FPI success of 77.0 versus 78.7% (p = 0.36) and an OPI success of 92.2 versus 97.7% (p < 0.001). Conclusion. LT insertion failed in the first attempt in one out of five patients, with an overall failure rate in one out of 14 patients. When compared with the LT, the LMA had a cumulative 5.5% better OPI success rate.

  7. Basic entwinements: unassuming analogue inserts in basic digital modeling (courses)

    DEFF Research Database (Denmark)

    Wiesner, Thomas

    2012-01-01

    morphologies in a seemingly scaleless manipulative universe, simple, rapid-paced analogue sketching tool can be introduced to supplement a purely digital approach. Inserted casually, yet with almost acupunctural precision during digital coursework, the simple analogue sketching tools present a wide variety...

  8. Modeling of Porous Insertion Electrodes with Liquid Electrolyte

    DEFF Research Database (Denmark)

    West, Keld; Jacobsen, Torben; Atlung, Sven

    1982-01-01

    The dynamics of porous insertion electrodes during charge or discharge is described by a simplified mathematicalmodel, accounting for the coupled transport in electrode and electrolyte phases. A numerical method to evaluate theresponse of this model to either controlled potential or controlled...

  9. Chemo-port insertion: A cause of vocal cord palsy.

    Science.gov (United States)

    Alazzawi, Sarmad; Hindi, Khalid; Malik, Ausama; Wee, Chong Aun; Prepageran, Narayanan

    2015-11-01

    We describe extremely rare cases of vocal cord palsy following surgical insertion of a chemo port. Our cohort consisted of patients with cancer who developed hoarseness immediately after central venous line placement for the administration of chemotherapy, with vocal cord palsy confirmed with flexible laryngoscopy. Given the timing, central venous line placement appears to be the most likely cause. PMID:26108861

  10. SPS, quadrupole and vacuum chamber for low-beta insertion

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    During operation of the SPS as a proton-antiproton collider, 2 low-beta insertions (in LSS4 and LSS5) reduced the beam sizes and thereby increased the luminosity. The quadrupoles close to the intersection points had special, "flower-shaped", vacuum chambers. A detailed description is given in CERN Annual Report 1981, p.121.

  11. PRODUCTION OF CAST DIE INSERTS FOR HOT STRAINING

    Directory of Open Access Journals (Sweden)

    L. R. Dudetskaja

    2009-01-01

    Full Text Available The paper discusses distinctive design features of casting molds and technological aspects of producing cast inserts from 5ХНМЛ pressed steel. The designs of long-life metal shell molds are described. They ensure saving of molding material, increase of accepted material and improvement of quality of castings.

  12. ArcGIS Tool: Inserts file name into attribute table

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This ArcGIS model inserts a file name into a feature class attribute table. The tool allows an user to identify features by a field that reference the name of the...

  13. Engine valve and seat insert wear study with a simulator

    Institute of Scientific and Technical Information of China (English)

    Y.S.Wang; S.Narasimhan

    2001-01-01

    The demands on higher performance and the increasing use of alternative fuels chal-lenge engine valves now with greater wear problems than before. A seat wear simulator was builtto evaluate the compatibility and wear of valve and seat insert. The rig test results have been suc-cessfully correlated with engine test results. In this study, intake valves made from Sil 1 materialwere treated with salt bath nitride processes and tested against six different insert materials. Wearresistance of these combinations was ranked and compared to the Sil 1 valve without nitriding.The test results demonstrate that nitriding improved valve seat wear resistance. In the total valveseat recession ranking, the combination of nitrided Sil 1 valve against T 400 insert exhibited theleast total recession among the nineteen combinations of valve and insert tested. The results indi-cate that the valve seat wear mechanisms are a complex combination of adhesion and shearstrain. The nitrides in the compound layer of nitrided valves gave strong atomic bonding, higherhardness, compressive residual stresses, and possible low friction, thus resulted in the superiorwear performance.

  14. Folding and insertion thermodynamics of the transmembrane WALP peptide

    Energy Technology Data Exchange (ETDEWEB)

    Bereau, Tristan, E-mail: bereau@mpip-mainz.mpg.de [Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz (Germany); Bennett, W. F. Drew [Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Pfaendtner, Jim [Department of Chemical Engineering, University of Washington, Seattle, Washington 98195 (United States); Deserno, Markus [Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Karttunen, Mikko [Department of Mathematics and Computer Science & Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, MetaForum, 5600 MB Eindhoven (Netherlands)

    2015-12-28

    The anchor of most integral membrane proteins consists of one or several helices spanning the lipid bilayer. The WALP peptide, GWW(LA){sub n} (L)WWA, is a common model helix to study the fundamentals of protein insertion and folding, as well as helix-helix association in the membrane. Its structural properties have been illuminated in a large number of experimental and simulation studies. In this combined coarse-grained and atomistic simulation study, we probe the thermodynamics of a single WALP peptide, focusing on both the insertion across the water-membrane interface, as well as folding in both water and a membrane. The potential of mean force characterizing the peptide’s insertion into the membrane shows qualitatively similar behavior across peptides and three force fields. However, the Martini force field exhibits a pronounced secondary minimum for an adsorbed interfacial state, which may even become the global minimum—in contrast to both atomistic simulations and the alternative PLUM force field. Even though the two coarse-grained models reproduce the free energy of insertion of individual amino acids side chains, they both underestimate its corresponding value for the full peptide (as compared with atomistic simulations), hinting at cooperative physics beyond the residue level. Folding of WALP in the two environments indicates the helix as the most stable structure, though with different relative stabilities and chain-length dependence.

  15. Contrast-free endoscopic stent insertion in malignant biliary obstruction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To present a case series of MRCP-guided endoscopic biliary stent placement, performed entirely without contrast injection.METHODS: Contrast-free endoscopic biliary drainage was attempted in 20 patients with malignant obstruction,unsuitable for resection on the basis of tumor extent or medical illness. MRCP images were used to confirm the diagnosis of tumor, to exclude other biliary diseases and to demonstrate the stenoses as well as dilation of proximal liver segments. The procedure was carried out under conscious sedation. Patients were placed in the left lateral decubitus position. The endoscope was inserted, the papilla identified and cannulated by a papillotome. A guide wire was inserted and guided deeply into the biliary tree, above the stenosis, by fluoroscopy. A papillotomy approximately 1 cm. long was performed and the papillotome was exchanged with a guiding-catheter. A 10 Fr, Amsterdam-type plastic stent,7 to 15 cm long, was finally inserted over the guide wire/guiding catheter by a pusher tube system.RESULTS: Successful stent insertion was achieved in all patients. There were no major complications. Successful drainage, with substantial reduction in bilirubin levels,was achieved in all patients.CONCLUSION: This new method of contrast-free endoscopic stenting in malignant biliary obstruction is a safe and effective method of palliation. However, a larger, randomized study comparing this new approach with the standard procedure is needed to confirm the findings of the present study.

  16. Multiple Binary Images Watermarking in Spatial and Frequency Domains

    Directory of Open Access Journals (Sweden)

    K.Ganesan

    2012-12-01

    Full Text Available Editing, reproduction and distribution of the digital multimedia are becoming extremely easier and faster with the existence of the internet and the availability of pervasive and powerful multimedia tools. Digital watermarking has emerged as a possible method to tackle these issues. This paper proposes a scheme using which more data can be inserted into an image in different domains using different techniques. This increases the embedding capacity. Using the proposed scheme 24 binary images can be embedded in the DCT domain and 12 binary images can be embedded in the spatial domain using LSB substitution technique in a single RGB image. The proposed scheme also provides an extra level of security to the watermark image by scrambling the image before embedding it into the host image. Experimental results show that the proposed watermarking method results in almost invisible difference between the watermarked image and the original image and is also robust against various image processing attacks.

  17. Multiple Binary Images Watermarking in Spatial and Frequency Domains

    Directory of Open Access Journals (Sweden)

    K.Ganesan

    2011-02-01

    Full Text Available Editing, reproduction and distribution of the digital multimedia are becoming extremely easier and fasterwith the existence of the internet and the availability of pervasive and powerful multimedia tools. Digitalwatermarking has emerged as a possible method to tackle these issues. This paper proposes a schemeusing which more data can be inserted into an image in different domains using different techniques. Thisincreases the embedding capacity. Using the proposed scheme 24 binary images can be embedded in theDCT domain and 12 binary images can be embedded in the spatial domain using LSB substitutiontechnique in a single RGB image. The proposed scheme also provides an extra level of security to thewatermark image by scrambling the image before embedding it into the host image. Experimental resultsshow that the proposed watermarking method results in almost invisible difference between thewatermarked image and the original image and is also robust against various image processing attacks.

  18. Domain Theory for Concurrency

    DEFF Research Database (Denmark)

    Nygaard, Mikkel

    Concurrent computation can be given an abstract mathematical treatment very similar to that provided for sequential computation by domain theory and denotational semantics of Scott and Strachey. A simple domain theory for concurrency is presented. Based on a categorical model of linear logic...... of affine-linear logic. This language adds to HOPLA an interesting tensor operation at the price of linearity constraints on the occurrences of variables. The tensor can be understood as a juxtaposition of independent processes, and allows Affine HOPLA to encode processes of the kind found in treatments...... of nondeterministic dataflow. The domain theory can be generalised to presheaf models, providing a more refined treatment of nondeterministic branching and supporting notions of bisimulation. The operational semantics for HOPLA is guided by the idea that derivations of transitions in the operational semantics should...

  19. Reasoning in incomplete domains

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, S.

    1979-01-01

    Most real-world domains differ from the micro-worlds traditionally used in A.I. in that they have an incomplete factual data base which changes over time. Understanding in these domains can be thought of as the gneration of plausible infoerences which are able to use the facts available, and respond to changes in them. A traditional rule interpreter such as Planner can be extended to construct plausible inferences in these domains by allowing assumptions to be made in applying rules, resultsing in simplifications of rules which can be used in an incomplete data base; monitoring the antecedents and consequents of a rule so that inferences can be maintained over a changing data base.

  20. Axion domain wall baryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Daido, Ryuji; Kitajima, Naoya [Department of Physics, Tohoku University,Sendai 980-8578 (Japan); Takahashi, Fuminobu [Department of Physics, Tohoku University,Sendai 980-8578 (Japan); Kavli IPMU, TODIAS, University of Tokyo,Kashiwa 277-8583 (Japan)

    2015-07-28

    We propose a new scenario of baryogenesis, in which annihilation of axion domain walls generates a sizable baryon asymmetry. Successful baryogenesis is possible for a wide range of the axion mass and decay constant, m≃10{sup 8}–10{sup 13} GeV and f≃10{sup 13}–10{sup 16} GeV. Baryonic isocurvature perturbations are significantly suppressed in our model, in contrast to various spontaneous baryogenesis scenarios in the slow-roll regime. In particular, the axion domain wall baryogenesis is consistent with high-scale inflation which generates a large tensor-to-scalar ratio within the reach of future CMB B-mode experiments. We also discuss the gravitational waves produced by the domain wall annihilation and its implications for the future gravitational wave experiments.

  1. Membrane fusion induced by the major lipid-binding domain of the cytoskeletal protein talin

    NARCIS (Netherlands)

    Isenberg, G; Doerhoefer, S; Hoekstra, D; Goldmann, WH

    2002-01-01

    Secondary structure predictions have led to the identification of a major membrane-anchoring domain of the cytoskeletal protein talin spanning from amino acid 385 to 406. Using a synthetically derived peptide of this region, researchers have shown that it inserts into POPC/POPG phospholipid membrane

  2. Atomic Pseudo-Valuation Domains

    CERN Document Server

    Stines, Elijah

    2012-01-01

    Pseudo-valuation domains have been studied since their introduction in 1978 by Hedstrom and Houston. Related objects, boundary valuation domains, were introduced by Maney in 2004. Here, it is shown that the class of atomic pseudo-valuation domains coincides with the class of boundary valuation domains. It is also shown that power series rings and generalized power series rings give examples of pseudo-valuation domains whose congruence lattices can be characterized. The paper also introduces, and makes use of, a sufficient condition on the group of divisibility of a domain to guarantee that it is a pseudo-valuation domain.

  3. Domain: Labour market

    NARCIS (Netherlands)

    Oude Mulders, J.; Wadensjö, E.; Hasselhorn, H.M.; Apt, W.

    2015-01-01

    This domain chapter is dedicated to summarize research on the effects of labour market contextual factors on labour market participation of older workers (aged 50+) and identify research gaps. While employment participation and the timing of (early) retirement is often modelled as an individual deci

  4. Normed Domains of Holomorphy

    Directory of Open Access Journals (Sweden)

    Steven G. Krantz

    2010-01-01

    Full Text Available We treat the classical concept of domain of holomorphy in ℂn when the holomorphic functions considered are restricted to lie in some Banach space. Positive and negative results are presented. A new view of the case n=1 is considered.

  5. Cellulose binding domain proteins

    Energy Technology Data Exchange (ETDEWEB)

    Shoseyov, Oded (Karmey Yosef, IL); Shpiegl, Itai (Rehovot, IL); Goldstein, Marc (Davis, CA); Doi, Roy (Davis, CA)

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  6. Skyrmions and domain walls

    OpenAIRE

    Piette, B.; Zakrzewski, W. J.

    1997-01-01

    We study the 3+1 dimensional Skyrme model with a mass term different from the usual one. We show that this new model possesses domain walls solutions. We describe how, in the equivalent 2+1 dimensional model, the Skyrmion is absorbed by the wall.

  7. A search for RNA insertions and NS3 gene duplication in the genome of cytopathic isolates of bovine viral diarrhea virus

    Directory of Open Access Journals (Sweden)

    V.L. Quadros

    2006-07-01

    Full Text Available Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV and an antigenically identical but cytopathic virus (cpBVDV can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98% to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.

  8. High-Resolution Tracking Asymmetric Lithium Insertion and Extraction and Local Structure Ordering in SnS2.

    Science.gov (United States)

    Gao, Peng; Wang, Liping; Zhang, Yu-Yang; Huang, Yuan; Liao, Lei; Sutter, Peter; Liu, Kaihui; Yu, Dapeng; Wang, En-Ge

    2016-09-14

    In the rechargeable lithium ion batteries, the rate capability and energy efficiency are largely governed by the lithium ion transport dynamics and phase transition pathways in electrodes. Real-time and atomic-scale tracking of fully reversible lithium insertion and extraction processes in electrodes, which would ultimately lead to mechanistic understanding of how the electrodes function and why they fail, is highly desirable but very challenging. Here, we track lithium insertion and extraction in the van der Waals interactions dominated SnS2 by in situ high-resolution TEM method. We find that the lithium insertion occurs via a fast two-phase reaction to form expanded and defective LiSnS2, while the lithium extraction initially involves heterogeneous nucleation of intermediate superstructure Li0.5SnS2 domains with a 1-4 nm size. Density functional theory calculations indicate that the Li0.5SnS2 is kinetically favored and structurally stable. The asymmetric reaction pathways may supply enlightening insights into the mechanistic understanding of the underlying electrochemistry in the layered electrode materials and also suggest possible alternatives to the accepted explanation of the origins of voltage hysteresis in the intercalation electrode materials. PMID:27504584

  9. Fuzzy Bases of Fuzzy Domains

    OpenAIRE

    Sanping Rao; Qingguo Li

    2013-01-01

    This paper is an attempt to develop quantitative domain theory over frames. Firstly, we propose the notion of a fuzzy basis, and several equivalent characterizations of fuzzy bases are obtained. Furthermore, the concept of a fuzzy algebraic domain is introduced, and a relationship between fuzzy algebraic domains and fuzzy domains is discussed from the viewpoint of fuzzy basis. We finally give an application of fuzzy bases, where the image of a fuzzy domain can be preserved under some special ...

  10. Atomic Pseudo-Valuation Domains

    OpenAIRE

    Stines, Elijah

    2012-01-01

    Pseudo-valuation domains have been studied since their introduction in 1978 by Hedstrom and Houston. Related objects, boundary valuation domains, were introduced by Maney in 2004. Here, it is shown that the class of atomic pseudo-valuation domains coincides with the class of boundary valuation domains. It is also shown that power series rings and generalized power series rings give examples of pseudo-valuation domains whose congruence lattices can be characterized. The paper also introduces, ...

  11. Research of Insertion Mechanism of Flexible Search and Rescue Robot

    Directory of Open Access Journals (Sweden)

    Shen Linyong

    2015-01-01

    Full Text Available Due to various factors, the global scope disaster events occur inevitably every year. Terrorism, natural disasters or destructive earthquakes tend to cause a large number of people buried in the ruins of buildings. The research of search and rescue instruments research is mainly focused on snake-like robot and life detector both at home and abroad. The endoscopic search and rescue robot in this paper combines the characteristics of these two kinds of search and rescue equipment. This thesis mainly studies the insertion mechanism of endoscopic flexible search and rescue robot. Based on the mechanics characteristics of the flexible robot body, this paper analyzes several common failure modes during the insertion into the ruins. This article puts forward the scheme of segmented gradual pulling-pushing, which plays an important role in promoting search and rescue work.

  12. Calculation of magnetic error fields in hybrid insertion devices

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory requires insertion devices with fields sufficiently accurate to take advantage of the small emittance of the ALS electron beam. To maintain the spectral performance of the synchrotron radiation and to limit steering effects on the electron beam these errors must be smaller than 0.25%. This paper develops a procedure for calculating the steering error due to misalignment of the easy axis of the permanent magnet material. The procedure is based on a three dimensional theory of the design of hybrid insertion devices developed by one of us. The acceptable tolerance for easy axis misalignment is found for a 5 cm period undulator proposed for the ALS. 11 refs., 5 figs

  13. Challenges for Insertion of Structural Nanomaterials in Aerospace Applications

    Science.gov (United States)

    Sochi, Emilie J.

    2012-01-01

    In the two decades since Iijima's report on carbon nanotubes (CNT), there has been great interest in realizing the benefits of mechanical properties observed at the nanoscale in large-scale structures. The weight savings possible due to dramatic improvements in mechanical properties relative to state-of-the-art material systems can be game changing for applications like aerospace vehicles. While there has been significant progress in commercial production of CNTs, major aerospace applications that take advantage of properties offered by this material have yet to be realized. This paper provides a perspective on the technical challenges and barriers for insertion of CNTs as an emerging material technology in aerospace applications and proposes approaches that may reduce the typical timeframe for technology maturation and insertion into aerospace structures.

  14. An overview of the insertion device development at SRRC

    CERN Document Server

    Hwang, C S; Fan, T C; Wang, C; Chen, J R; Chen, C T

    2001-01-01

    Five high performance insertion devices, namely W20, U10, U5, U9 and EPU5.6, have been constructed and installed in the storage ring of the Synchrotron Radiation Research Center (SRRC). Among them, the 2-m-long conventional undulator U10 and the 4-m-long elliptically polarized undulator EPU5.6 were designed and built in-house. These two devices have achieved high magnetic field quality and high spectral performance. To facilitate hard-X-ray experiments, the project of building a superconducting wavelength shifter (SWLS) and a superconducting multi-pole wiggler (SMPW) is ongoing. These two superconducting insertion devices were designed to be cryogen-free.

  15. Transients analysis by reactivity insertion in research reactors

    International Nuclear Information System (INIS)

    PARET code was used to simulate accidental situations arising from positive reactivity insertions, in order to analyze the behavior of RP-10 reactor. The simulations considered three different cases: First is for the reactor operating at 10 Mw nominal power with 3 pumps in use, the second, at 6.6 Mw with only one pump working. In all cases the reactor trip was assumed when a 12 Mw power level is reached. An additional simulation for the reactor operating at 50w before the reactivity insertion, showed to be the worst accidental situation of all cases because of the higher temperature and power rise. Hot channel thermohydraulic and kinetic parameters have been evaluated at each axial mesh point and transient time step. None of the cases showed melting of fuel plates

  16. Amyloid protein unfolding and insertion kinetics on neuronal membrane mimics

    Science.gov (United States)

    Qiu, Liming; Buie, Creighton; Vaughn, Mark; Cheng, Kwan

    2010-03-01

    Atomistic details of beta-amyloid (Aβ ) protein unfolding and lipid interaction kinetics mediated by the neuronal membrane surface are important for developing new therapeutic strategies to prevent and cure Alzheimer's disease. Using all-atom MD simulations, we explored the early unfolding and insertion kinetics of 40 and 42 residue long Aβ in binary lipid mixtures with and without cholesterol that mimic the cholesterol-depleted and cholesterol-enriched lipid nanodomains of neurons. The protein conformational transition kinetics was evaluated from the secondary structure profile versus simulation time plot. The extent of membrane disruption was examined by the calculated order parameters of lipid acyl chains and cholesterol fused rings as well as the density profiles of water and lipid headgroups at defined regions across the lipid bilayer from our simulations. Our results revealed that both the cholesterol content and the length of the protein affect the protein-insertion and membrane stability in our model lipid bilayer systems.

  17. Operation of synchrotron light sources with multiple insertion devices

    International Nuclear Information System (INIS)

    The stability requirements of the next generation of synchrotron radiation facilities have been achieved on insertion device beamlines of existing rings. However, one insertion device (ID) affects the stored beam and hence the performance of all the other beamlines. Since the effects of the undulators are cumulative, higher levels of performance are required of the accelerator in order to meet and exceed present day standards in rings with many undulators. This paper will report experience to date in the areas mentioned above at several multi-undulator facilities and efforts to address these problems at facilities in the planning and construction phase. Section II will treat orbit control and feedback. Section III will describe work on linear and nonlinear effects of ideal undulators in accelerators. Section IV will mention undulator imperfections and the demands they make on the accelerator control system

  18. First two barrel ECAL supermodules inserted in CMS HCAL

    CERN Multimedia

    K.Bell

    2006-01-01

    The first two barrel "supermodules" for the CMS Electromagnetic Calorimeter (ECAL) have been inserted into the barrel hadron calorimeter (HCAL) in the experimental hall (called SX5) in Cessy in preparation for the forthcoming magnet test and cosmic challenge (MTCC). Each of the two supermodules contains 1700 lead tungstate crystals in glass-fibre alveolar support structures, with associated avalanche photodiodes (APDs, for scintillation light detection), electronics and cooling system. The barrel ECAL will consist of 36 supermodules, many of which have already been produced (see CERN Bulletin 17-18, 2006). Team from CMS ECAL, CMS Integration and CEA-DAPNIA were involved in the insertion, with the production/integration of the supermodules themselves involving many technicians, engineers and physicists from many institutes. From left to right: Olivier Teller, Maf Alidra and Lucien Veillet.

  19. Strain measurement at the knee ligament insertion sites

    OpenAIRE

    Hinterwimmer, S; Baumgart, R.; Plitz, W.

    2003-01-01

    We describe the modification of an existing method of ligament strain measurement at the knee joint in detail. At ten fresh joint specimens we used that technique where strain gauges are attached to the ligamentous insertions and origins. We both improved the preparation of the attachment site and the application of the strain gauges. In a special apparatus the specimens were moved from 0degrees extension to 100degrees flexion while simulating muscle strength and axial force. Testing was perf...

  20. Tumor track seeding: A new complication of fiducial marker insertion

    OpenAIRE

    Zeal Patel, MD; Michele Retrouvey, MD; Harlan Vingan, MD; Scott Williams, MD

    2015-01-01

    In the United States, lung cancer is the leading cause of cancer-related death. Candidates for tumor ablation using CyberKnife® require fiducial placement in or near the target tumor to achieve precision. Placing these reference points may lead to complications including pneumothorax and/or hemorrhage. We report a new complication: the appearance of metastatic foci along the track of the fiducial marker. Since the marker was inserted by traversing the original primary tumor, we hypothesize th...

  1. Non-harmful insertion of data mimicking computer network attacks

    Science.gov (United States)

    Neil, Joshua Charles; Kent, Alexander; Hash, Jr, Curtis Lee

    2016-06-21

    Non-harmful data mimicking computer network attacks may be inserted in a computer network. Anomalous real network connections may be generated between a plurality of computing systems in the network. Data mimicking an attack may also be generated. The generated data may be transmitted between the plurality of computing systems using the real network connections and measured to determine whether an attack is detected.

  2. The first insertion devices at SSRL - some personal recollections

    Energy Technology Data Exchange (ETDEWEB)

    Winick, H. [Stanford Linear Accelerator Center, CA (United States)

    1995-02-01

    The author recounts his experiences with insertion devices at the Stanford Synchrotron Radiation Laboratory. His first experiences with wigglers occured at the Cambridge Electron Accelerator, and was carried over to SSRL with the proposal for a six pole electromagnetic wiggler. Most modern undulators, and many wigglers are now designed around permanent magnets, and the origin of this transition at SSRL was rather fortuitous and humorous. It reflects some of the personality characteristics of Klaus Halbach.

  3. Epigenetic Suppression of T-DNA Insertion Mutants in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Yangbin Gao; Yunde Zhao

    2013-01-01

    T-DNA insertion mutants have been widely used to define gene functions in Arabidopsis and in other plants.Here,we report an unexpected phenomenon of epigenetic suppression of T-DNA insertion mutants in Arabidopsis.When the two T-DNA insertion mutants,yucl-1 and ag-TD,were crossed together,the defects in all of the ag-TD plants in the F2 population were partially suppressed regardless of the presence of yucl-1.Conversion of ag-TD to the suppressed ag-TD (named as ag-TD*) did not follow the laws of Mendelian genetics.The ag-TD* could be stably transmitted for many generations without reverting to ag-TD,and ag-TD* had the capacity to convert ag-TD to ag-TD*.We show that epigenetic suppression of T-DNA mutants is not a rare event,but certain structural features in the T-DNA mutants are needed in order for the suppression to take place.The suppressed T-DNA mutants we observed were all intronic T-DNA mutants and the T-DNA fragments in both the trigger T-DNA as well as in the suppressed T-DNA shared stretches of identical sequences.We demonstrate that the suppression of intronic T-DNA mutants is mediated by trans-interactions between two ToDNA insertions.This work shows that caution is needed when intronic T-DNA mutants are used.

  4. Power distribution from insertion device x-ray sources

    International Nuclear Information System (INIS)

    Insertion device (ID) synchrotron x-ray sources on present day and next-generation synchrotron facilities have very attractive spectral properties. In addition however, they are capable of producing x-ray beams with large powers and in some cases, unprecedented power densities. An overview of the spatial and frequency distributions of these sources including the effects of synchrotron particle beam emittance is presented

  5. Insertion DNA Accelerates Meiotic Interchromosomal Recombination in Arabidopsis thaliana.

    Science.gov (United States)

    Sun, Xiao-Qin; Li, Ding-Hong; Xue, Jia-Yu; Yang, Si-Hai; Zhang, Yan-Mei; Li, Mi-Mi; Hang, Yue-Yu

    2016-08-01

    Nucleotide insertions/deletions are ubiquitous in eukaryotic genomes, and the resulting hemizygous (unpaired) DNA has significant, heritable effects on adjacent DNA. However, little is known about the genetic behavior of insertion DNA. Here, we describe a binary transgenic system to study the behavior of insertion DNA during meiosis. Transgenic Arabidopsis lines were generated to carry two different defective reporter genes on nonhomologous chromosomes, designated as "recipient" and "donor" lines. Double hemizygous plants (harboring unpaired DNA) were produced by crossing between the recipient and the donor, and double homozygous lines (harboring paired DNA) via self-pollination. The transfer of the donor's unmutated sequence to the recipient generated a functional β-glucuronidase gene, which could be visualized by histochemical staining and corroborated by polymerase chain reaction amplification and sequencing. More than 673 million seedlings were screened, and the results showed that meiotic ectopic recombination in the hemizygous lines occurred at a frequency  >6.49-fold higher than that in the homozygous lines. Gene conversion might have been exclusively or predominantly responsible for the gene correction events. The direct measurement of ectopic recombination events provided evidence that an insertion, in the absence of an allelic counterpart, could scan the entire genome for homologous counterparts with which to pair. Furthermore, the unpaired (hemizygous) architectures could accelerate ectopic recombination between itself and interchromosomal counterparts. We suggest that the ectopic recombination accelerated by hemizygous architectures may be a general mechanism for interchromosomal recombination through ubiquitously dispersed repeat sequences in plants, ultimately contributing to genetic renovation and eukaryotic evolution. PMID:27189569

  6. Cytoplasmic Organelle DNA Preferentially Inserts into Open Chromatin

    OpenAIRE

    Wang, Dong; Timmis, Jeremy N.

    2013-01-01

    DNA transfer from chloroplasts and mitochondria to the nucleus is ongoing in eukaryotes but the mechanisms involved are poorly understood. Mitochondrial DNA was observed to integrate into the nuclear genome through DNA double-strand break repair in Nicotiana tabacum. Here, 14 nuclear insertions of chloroplast DNA (nupts) that are unique to Oryza sativa subsp. indica were identified. Comparisons with the preinsertion nuclear loci identified in the related subspecies, O. sativa subsp. japonica,...

  7. A training simulator for ultrasound-guided percutaneous nephrostomy insertion

    OpenAIRE

    Rock, B G; Leonard, A P; Freeman, S. J.

    2010-01-01

    Increasing trainee numbers and changes to working patterns have resulted in a scarcity of training opportunities for training-grade doctors wishing to learn nephrostomy tube insertion techniques. A method of introducing trainees to the skills required to perform percutaneous nephrostomy in a safe, non-threatening environment, without risk to patients, is desirable. Commercial and biological nephrostomy phantoms are available, but they are expensive and not widely available, and a cheap, safe,...

  8. Soft Tissue Phantoms for Realistic Needle Insertion: A Comparative Study.

    Science.gov (United States)

    Leibinger, Alexander; Forte, Antonio E; Tan, Zhengchu; Oldfield, Matthew J; Beyrau, Frank; Dini, Daniele; Rodriguez Y Baena, Ferdinando

    2016-08-01

    Phantoms are common substitutes for soft tissues in biomechanical research and are usually tuned to match tissue properties using standard testing protocols at small strains. However, the response due to complex tool-tissue interactions can differ depending on the phantom and no comprehensive comparative study has been published to date, which could aid researchers to select suitable materials. In this work, gelatin, a common phantom in literature, and a composite hydrogel developed at Imperial College, were matched for mechanical stiffness to porcine brain, and the interactions during needle insertions within them were analyzed. Specifically, we examined insertion forces for brain and the phantoms; we also measured displacements and strains within the phantoms via a laser-based image correlation technique in combination with fluorescent beads. It is shown that the insertion forces for gelatin and brain agree closely, but that the composite hydrogel better mimics the viscous nature of soft tissue. Both materials match different characteristics of brain, but neither of them is a perfect substitute. Thus, when selecting a phantom material, both the soft tissue properties and the complex tool-tissue interactions arising during tissue manipulation should be taken into consideration. These conclusions are presented in tabular form to aid future selection. PMID:26666228

  9. Enhancement of Selection, Bubble and Insertion Sorting Algorithm

    Directory of Open Access Journals (Sweden)

    Muhammad Farooq Umar

    2014-07-01

    Full Text Available In everyday life there is a large amount of data to arrange because sorting removes any ambiguities and make the data analysis and data processing very easy, efficient and provides with cost less effort. In this study a set of improved sorting algorithms are proposed which gives better performance and design idea. In this study five new sorting algorithms (Bi-directional Selection Sort, Bi-directional bubble sort, MIDBiDirectional Selection Sort, MIDBidirectional bubble sort and linear insertion sort are presented. Bi-directional Selection Sort and MIDBiDirectional Selection Sort are the enhancement on basic selection sort while Bidirectional bubble sort and MIDBidirectional bubble sort are the enhancement on basic bubble sort by changing the selection and swapping mechanism of data for sorting. Enhanced sorting algorithms reduced the iteration by half and quarter times respectively. Asymptotically complexities of these algorithms are reduced to O (n2/2 and O (n2/4 from O (n2. Linear insertion sort is the enhancement of insertion sort by changing the design of algorithm (convert two loops to one loop. So asymptotically this algorithm is converted to linear time complexity from quadratic complexity. These sorting algorithms are described using C. The proposed algorithms are analyzed using asymptotic analysis and also using machine-running time and compared with their basic sorting algorithms. In this study we also discuss how the performance and complexity can be improved by optimizing the code and design.

  10. Coaxial needle insertion assistant with enhanced force feedback.

    Science.gov (United States)

    De Lorenzo, Danilo; Koseki, Yoshihiko; De Momi, Elena; Chinzei, Kiyoyuki; Okamura, Allison M

    2013-02-01

    Many medical procedures involving needle insertion into soft tissues, such as anesthesia, biopsy, brachytherapy, and placement of electrodes, are performed without image guidance. In such procedures, haptic detection of changing tissue properties at different depths during needle insertion is important for needle localization and detection of subsurface structures. However, changes in tissue mechanical properties deep inside the tissue are difficult for human operators to sense, because the relatively large friction force between the needle shaft and the surrounding tissue masks the smaller tip forces. A novel robotic coaxial needle insertion assistant, which enhances operator force perception, is presented. This one-degree-of-freedom cable-driven robot provides to the operator a scaled version of the force applied by the needle tip to the tissue, using a novel design and sensors that separate the needle tip force from the shaft friction force. The ability of human operators to use the robot to detect membranes embedded in artificial soft tissue was tested under the conditions of 1) tip force and shaft force feedback, and 2) tip force only feedback. The ratio of successful to unsuccessful membrane detections was significantly higher (up to 50%) when only the needle tip force was provided to the user. PMID:23193302

  11. Localized control of the orbit in the RHIC insertions

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, S.

    1992-08-01

    It is proposed here that, for RHIC92 insertions, we remove the corrector from Ql and the beam position monitor (BPM) from Q2 in order to alleviate difficulties associated with the physical layout of the quadrupole triplet (Ql-Q2-Q3). Furthermore, it is suggested that there should be both (horizontal and vertical) types of BPMs at each end of the free space between Q3 and Q4 and between Q7 and Q8 so that one can measure the direction of the closed orbit. With this model, a localized control of the beam position and angle at the interaction point (IP) with either four or six correctors has been investigated. Similarly, a control of the orbit within an insertion for minimizing the orbit displacements at seven (or eight) BPM locations with nine (or ten) correctors in each transverse direction has been studied. Examples are given for the beta at IP = 2m, 10m, 20m, and 200m. It is shown that the design value of the integrated field strength of 0.3 T-m for each corrector should be sufficient for the tasks considered here except for some cases with extreme parameter values. At the same time, it is emphasized that the overall correction of the closed orbit for the entire ring (arcs and insertions) should be re-examined for RHIC92 lattice with the proposed arrangement of correctors and BPMS.

  12. NURSING CARE IN PATIENTS NEONATES WITH PERIPHERALLY INSERTED CENTRAL CATHETER

    Directory of Open Access Journals (Sweden)

    Anacilda Oliveira Vieira

    2013-12-01

    Full Text Available Introduction: The PICC (peripherally inserted central catheter is a long flexible catheter which is inserted through a peripheral vein, progresses through a needle introducer until the final portion of the vena cava, acquiring characteristics of a central catheter. Objective: To point out the main theoretical and scientific ideas that demonstrate the reliability, competence and ability of nurses to perform the PICC. Methodology: Systematic review of articles, which were found by searching the database scientific journals and bibliographies area. Results: The success of integration depends on the patient assessment and choice of venous access where the catheter will be positioned, and its tip should be in the middle third of the superior vena cava, or the middle third of the inferior vena cava. In neonates, which are used more frequently, proper positioning of the catheter is through nursing care in making the dressing, and the first 24 hours it should be compressive. Ideally, the PICC remains in the vein for periods longer than seven days or until the end of treatment, thus decreasing invasive procedures. Conclusion: According to the Federal Board of Nursing (COFEN, it is lawful for the insertion of PICC nurses, provided it has undergone professional training.

  13. Modeling and characterization of partially inserted electrical connector faults

    Science.gov (United States)

    Tokgöz, ćaǧatay; Dardona, Sameh; Soldner, Nicholas C.; Wheeler, Kevin R.

    2016-03-01

    Faults within electrical connectors are prominent in avionics systems due to improper installation, corrosion, aging, and strained harnesses. These faults usually start off as undetectable with existing inspection techniques and increase in magnitude during the component lifetime. Detection and modeling of these faults are significantly more challenging than hard failures such as open and short circuits. Hence, enabling the capability to locate and characterize the precursors of these faults is critical for timely preventive maintenance and mitigation well before hard failures occur. In this paper, an electrical connector model based on a two-level nonlinear least squares approach is proposed. The connector is first characterized as a transmission line, broken into key components such as the pin, socket, and connector halves. Then, the fact that the resonance frequencies of the connector shift as insertion depth changes from a fully inserted to a barely touching contact is exploited. The model precisely captures these shifts by varying only two length parameters. It is demonstrated that the model accurately characterizes a partially inserted connector.

  14. ANATOMICAL VARIATION OF PALMARIS LONGUS: TENDINOUS ORIGIN AND FLESHY INSERTION

    Directory of Open Access Journals (Sweden)

    Buddhadeb Ghosh

    2015-03-01

    Full Text Available A tendinous origin and fleshy insertion of palmaris longus muscle was observed in the left forearm during routine dissection which was performed on adult male cadaver in the department of Anatomy, Dr. Rajendra Prasad Government Medical College. It was having long tendinous origin from the medial epicondyle of the humerus and the surrounding deep fascia. It was fusiform at the lower middle of the forearm. The fleshy muscular insertion was noted to the flexor retinaculum and few muscular fibers interdigitate with flexor carpi ulnaris muscle and palmar aponeurosis. The length of tendon was 19 inches and fleshy muscular length was 11inches. The median nerve and ulnar nerve was covered by this fleshy insertion. This palmaris longus variation is helpful for the surgeon and the radiologist, orthopaedic, plastic surgeon during any diagnosis of the forearm because this fleshy part of muscle can compress the median nerve and ulnar nerve or it can be mistaken as a tumor or ganglion during radiological or clinical examination.

  15. Folding and insertion thermodynamics of the transmembrane WALP peptide

    CERN Document Server

    Bereau, Tristan; Pfaendtner, Jim; Deserno, Markus; Karttunen, Mikko

    2015-01-01

    The anchor of most integral membrane proteins consists of one or several helices spanning the lipid bilayer. The WALP peptide, GWW(LA)$_n$(L)WWA, is a common model helix to study the fundamentals of protein insertion and folding, as well as helix-helix association in the membrane. Its structural properties have been illuminated in a large number of experimental and simulation studies. In this combined coarse-grained and atomistic simulation study, we probe the thermodynamics of a single WALP peptide, focusing on both the insertion across the water-membrane interface, as well as folding in both water and a membrane. The potential of mean force characterizing the peptide's insertion into the membrane shows qualitatively similar behavior across peptides and three force fields. However, the Martini force field exhibits a pronounced secondary minimum for an adsorbed interfacial state, which may even become the global minimum---in contrast to both atomistic simulations and the alternative PLUM force field. Even tho...

  16. Examining Prebiotic Chemistry Using O(^1D) Insertion Reactions

    Science.gov (United States)

    Hays, Brian M.; Laas, Jacob C.; Weaver, Susanna L. Widicus

    2013-06-01

    Aminomethanol, methanediol, and methoxymethanol are all prebiotic molecules expected to form via photo-driven grain surface chemistry in the interstellar medium (ISM). These molecules are expected to be precursors for larger, biologically-relevant molecules in the ISM such as sugars and amino acids. These three molecules have not yet been detected in the ISM because of the lack of available rotational spectra. A high resolution (sub)millimeter spectrometer coupled to a molecular source is being used to study these molecules using O(^1D) insertion reactions. The O(^1D) chemistry is initiated using an excimer laser, and the products of the insertion reactions are adiabatically cooled using a supersonic expansion. Experimental parameters are being optimized by examination of methanol formed from O(^1D) insertion into methane. Theoretical studies of the structure and reaction energies for aminomethanol, methanediol, and methoxymethanol have been conducted to guide the laboratory studies once the methanol experiment has been optimized. The results of the calculations and initial experimental results will be presented.

  17. Glucanases and Chitinases as Causal Agents in the Protection of Acacia Extrafloral Nectar from Infestation by Phytopathogens1[W][OA

    Science.gov (United States)

    González-Teuber, Marcia; Pozo, María J.; Muck, Alexander; Svatos, Ales; Adame-Álvarez, Rosa M.; Heil, Martin

    2010-01-01

    Nectars are rich in primary metabolites and attract mutualistic animals, which serve as pollinators or as an indirect defense against herbivores. Their chemical composition makes nectars prone to microbial infestation. As protective strategy, floral nectar of ornamental tobacco (Nicotiana langsdorffii × Nicotiana sanderae) contains “nectarins,” proteins producing reactive oxygen species such as hydrogen peroxide. By contrast, pathogenesis-related (PR) proteins were detected in Acacia extrafloral nectar (EFN), which is secreted in the context of defensive ant-plant mutualisms. We investigated whether these PR proteins protect EFN from phytopathogens. Five sympatric species (Acacia cornigera, A. hindsii, A. collinsii, A. farnesiana, and Prosopis juliflora) were compared that differ in their ant-plant mutualism. EFN of myrmecophytes, which are obligate ant-plants that secrete EFN constitutively to nourish specialized ant inhabitants, significantly inhibited the growth of four out of six tested phytopathogenic microorganisms. By contrast, EFN of nonmyrmecophytes, which is secreted only transiently in response to herbivory, did not exhibit a detectable inhibitory activity. Combining two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with nanoflow liquid chromatography-tandem mass spectrometry analysis confirmed that PR proteins represented over 90% of all proteins in myrmecophyte EFN. The inhibition of microbial growth was exerted by the protein fraction, but not the small metabolites of this EFN, and disappeared when nectar was heated. In-gel assays demonstrated the activity of acidic and basic chitinases in all EFNs, whereas glucanases were detected only in EFN of myrmecophytes. Our results demonstrate that PR proteins causally underlie the protection of Acacia EFN from microorganisms and that acidic and basic glucanases likely represent the most important prerequisite in this defensive function. PMID:20023149

  18. Sequence/structural analysis of xylem proteome emphasizes pathogenesis-related proteins, chitinases and β-1, 3-glucanases as key players in grapevine defense against Xylella fastidiosa.

    Science.gov (United States)

    Chakraborty, Sandeep; Nascimento, Rafael; Zaini, Paulo A; Gouran, Hossein; Rao, Basuthkar J; Goulart, Luiz R; Dandekar, Abhaya M

    2016-01-01

    Background. Xylella fastidiosa, the causative agent of various plant diseases including Pierce's disease in the US, and Citrus Variegated Chlorosis in Brazil, remains a continual source of concern and economic losses, especially since almost all commercial varieties are sensitive to this Gammaproteobacteria. Differential expression of proteins in infected tissue is an established methodology to identify key elements involved in plant defense pathways. Methods. In the current work, we developed a methodology named CHURNER that emphasizes relevant protein functions from proteomic data, based on identification of proteins with similar structures that do not necessarily have sequence homology. Such clustering emphasizes protein functions which have multiple copies that are up/down-regulated, and highlights similar proteins which are differentially regulated. As a working example we present proteomic data enumerating differentially expressed proteins in xylem sap from grapevines that were infected with X. fastidiosa. Results. Analysis of this data by CHURNER highlighted pathogenesis related PR-1 proteins, reinforcing this as the foremost protein function in xylem sap involved in the grapevine defense response to X. fastidiosa. β-1, 3-glucanase, which has both anti-microbial and anti-fungal activities, is also up-regulated. Simultaneously, chitinases are found to be both up and down-regulated by CHURNER, and thus the net gain of this protein function loses its significance in the defense response. Discussion. We demonstrate how structural data can be incorporated in the pipeline of proteomic data analysis prior to making inferences on the importance of individual proteins to plant defense mechanisms. We expect CHURNER to be applicable to any proteomic data set. PMID:27257535

  19. Chitinase 3-Like 1 (Chil1) Regulates Survival and Macrophage-Mediated Interleukin-1β and Tumor Necrosis Factor Alpha during Pseudomonas aeruginosa Pneumonia.

    Science.gov (United States)

    Marion, Chad R; Wang, Jianmiao; Sharma, Lokesh; Losier, Ashley; Lui, Wei; Andrews, Nathaniel; Elias, Jack A; Kazmierczak, Barbara I; Roy, Craig R; Dela Cruz, Charles S

    2016-07-01

    Pseudomonas aeruginosa causes hospital-acquired pneumonia and is associated with high mortality. An effective response to such an infection includes efficient clearance of pathogenic organisms while limiting collateral damage from the host inflammatory response, known as host resistance and host tolerance, respectively. P. aeruginosa expresses a type III secretion system (T3SS) needle complex that induces NLRC4 (NOD-like receptor C4) activation, interleukin-1β (IL-1β) production, and host tissue damage. Chitinase 3-like-1 (Chil1) is expressed during infection and binds to its receptor, IL-13 receptor α2 (IL-13Rα2), to regulate the pathogen-host response during Streptococcus pneumoniae infection, but the role Chil1 plays in balancing the host resistance and host tolerance during P. aeruginosa pneumonia is not known. We conducted experiments using C57BL/6 mice with or without a genetic deficiency of Chil1 and demonstrated that Chil1-deficient mice succumb to P. aeruginosa infection more rapidly than the wild type (WT). The decreased survival time in infected Chil1-deficient mice is associated with more neutrophils recruited to the airways, more lung parenchymal damage, and increased pulmonary consolidation while maintaining equivalent bacterial killing compared to WT mice. Infected Chil1-deficient mice and bone marrow-derived macrophages (BMDMs) from Chil1-deficient mice have increased production of tumor necrosis factor alpha (TNF-α) and IL-1β compared to infected WT mice and macrophages. Infection of Chil1-deficient BMDMs with non-NLRC4-triggering P. aeruginosa, which is deficient in the T3SS needle complex, did not alter the excessive IL-1β production compared to BMDMs from WT mice. The addition of recombinant Chil1 decreases the excessive IL-1β production but only partially rescues stimulated BMDMs from IL-13Rα2-deficient mice. Our data provide mechanistic insights into how Chil1 regulates P. aeruginosa-induced host responses. PMID:27141083

  20. BjMYB1, a transcription factor implicated in plant defence through activating BjCHI1 chitinase expression by binding to a W-box-like element

    Science.gov (United States)

    Gao, Ying; Jia, Shuangwei; Wang, Chunlian; Wang, Fujun; Wang, Fajun; Zhao, Kaijun

    2016-01-01

    We previously identified the W-box-like-4 (Wbl-4) element (GTAGTGACTCAT), one of six Wbl elements in the BjC-P promoter of the unusual chitinase gene BjCHI1 from Brassica juncea, as the core element responsive to fungal infection. Here, we report the isolation and characterization of the cognate transcription factor interacting with the Wbl-4 element. Using Wbl-4 as a target, we performed yeast one-hybrid screening of a B. juncea cDNA library and isolated an R2R3-MYB transcription factor designated as BjMYB1. BjMYB1 was localized in the nucleus of plant cells. EMSA assays confirmed that BjMYB1 binds to the Wbl-4 element. Transiently expressed BjMYB1 up-regulated the activity of the BjC-P promoter through its binding to the Wbl-4 element in tobacco (Nicotiana benthamiana) leaves. In B. juncea, BjMYB1 displayed a similar induced expression pattern as that of BjCHI1 upon infection by the fungus Botrytis cinerea. Moreover, heterogeneous overexpression of BjMYB1 significantly elevated the resistance of transgenic Arabidopsis thaliana to the fungus B. cinerea. These results suggest that BjMYB1 is potentially involved in host defence against fungal attack through activating the expression of BjCHI1 by binding to the Wbl-4 element in the BjC-P promoter. This finding demonstrates a novel DNA target of plant MYB transcription factors. PMID:27353280

  1. Alternative splicing of basic chitinase gene PR3b in the low-nicotine mutants of Nicotiana tabacum L. cv. Burley 21

    Science.gov (United States)

    Ma, Haoran; Wang, Feng; Wang, Wenjing; Yin, Guoying; Zhang, Dingyu; Ding, Yongqiang; Timko, Michael P.; Zhang, Hongbo

    2016-01-01

    Two unlinked semi-dominant loci, A (NIC1) and B (NIC2), control nicotine and related alkaloid biosynthesis in Burley tobaccos. Mutations in either or both loci (nic1 and nic2) lead to low nicotine phenotypes with altered environmental stress responses. Here we show that the transcripts derived from the pathogenesis-related (PR) protein gene PR3b are alternatively spliced to a greater extent in the nic1 and nic2 mutants of Burley 21 tobacco and the nic1nic2 double mutant. The alternative splicing results in a deletion of 65 nucleotides and introduces a premature stop codon into the coding region of PR3b that leads to a significant reduction of PR3b specific chitinase activity. Assays of PR3b splicing in F2 individuals derived from crosses between nic1 and nic2 mutants and wild-type plants showed that the splicing phenotype is controlled by the NIC1 and NIC2 loci, even though NIC1 and NIC2 are unlinked loci. Moreover, the transcriptional analyses showed that the splicing patterns of PR3b in the low-nicotine mutants were differentially regulated by jasmonate (JA) and ethylene (ET). These data suggest that the NIC1 and NIC2 loci display differential roles in regulating the alternative splicing of PR3b in Burley 21. The findings in this study have provided valuable information for extending our understanding of the broader effects of the low-nicotine mutants of Burley 21 and the mechanism by which JA and ET signalling pathways post-transcriptionally regulate the activity of PR3b protein. PMID:27664270

  2. Increased Obesity-Associated Circulating Levels of the Extracellular Matrix Proteins Osteopontin, Chitinase-3 Like-1 and Tenascin C Are Associated with Colon Cancer

    Science.gov (United States)

    Catalán, Victoria; Gómez-Ambrosi, Javier; Rodríguez, Amaia; Ramírez, Beatriz; Izaguirre, Maitane; Hernández-Lizoain, José Luis; Baixauli, Jorge; Martí, Pablo; Valentí, Víctor; Moncada, Rafael; Silva, Camilo; Salvador, Javier; Frühbeck, Gema

    2016-01-01

    Background Excess adipose tissue represents a major risk factor for the development of colon cancer with inflammation and extracellular matrix (ECM) remodeling being proposed as plausible mechanisms. The aim of this study was to investigate whether obesity can influence circulating levels of inflammation-related extracellular matrix proteins in patients with colon cancer (CC), promoting a microenvironment favorable for tumor growth. Methods Serum samples obtained from 79 subjects [26 lean (LN) and 53 obese (OB)] were used in the study. Enrolled subjects were further subclassified according to the established diagnostic protocol for CC (44 without CC and 35 with CC). Anthropometric measurements as well as circulating metabolites and hormones were determined. Circulating concentrations of the ECM proteins osteopontin (OPN), chitinase-3-like protein 1 (YKL-40), tenascin C (TNC) and lipocalin-2 (LCN-2) were determined by ELISA. Results Significant differences in circulating OPN, YKL-40 and TNC concentrations between the experimental groups were observed, being significantly increased due to obesity (P<0.01) and colon cancer (P<0.05). LCN-2 levels were affected by obesity (P<0.05), but no differences were detected regarding the presence or not of CC. A positive association (P<0.05) with different inflammatory markers was also detected. Conclusions To our knowledge, we herein show for the first time that obese patients with CC exhibit increased circulating levels of OPN, YKL-40 and TNC providing further evidence for the influence of obesity on CC development via ECM proteins, representing promising diagnostic biomarkers or target molecules for therapeutics. PMID:27612200

  3. Reconstitution technology of Charpy surveillance specimens with short insert length

    International Nuclear Information System (INIS)

    As for the shortage of the surveillance specimens to monitor the effect of the irradiation embrittlement of reactor pressure vessels (RPV) materials in case of longer-term operation than present surveillance program of nuclear power plants, the reconstitution of them is considered to be the promising measures. Although the length of the specimen insert is required not less than 18 mm in ASTM E1253-99 which is the technical standard to reconstitute Charpy specimens, the minimum length of the specimen insert required should be 10 mm when L-T direction Charpy specimens that have been applied to the early domestic nuclear power plants are reconstituted into T-L direction specimens in order to test the upper shelf absorbed energy of T-L direction specimens. This paper presents the current status of the research consigned by Ministry of Economy, Trade and Industry (METI) in Japan on the applicability of the reconstituted Charpy specimens with short length of the specimen insert. The length of the specimen insert to preserve the absorbed energy of the Charpy specimen is correlated to the absorbed energy of its material. The significant part of upper shelf energy is attributed to the energy for the plastic deformation zone near V-notch in the Charpy specimen. To preserve the absorbed energy, the anticipated plastically deformed zone shall not be affected by the reconstitution procedure. In order to clarify the condition for preserving the absorbed energy in the case of reconstitution, the preliminary data has been obtained using un-irradiated and irradiated Charpy specimens, and the following results have been obtained by the tests carried out in this research. 1) The plastic deformation widths have been estimated by measuring the hardness distribution near the V-notch of the un-irradiated Charpy impact tested specimens, correlated to the absorbed energy. 2) The absorbed energy shifts of reconstituted, un-irradiated Charpy specimens with various length of the specimen

  4. Test manufacturing of copper canisters with cast inserts. Assessment report

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, C.G

    1998-08-01

    The current design of canisters for the deep repository for spent nuclear fuel consists of an outer corrosion-protective copper casing in the form of a tubular section with lid and bottom and an inner pressure-resistant insert. The insert is designed to be manufactured by casting and inside are channels in which the fuel assemblies are to be placed. Over the last years, a number of full-scale manufacturing tests of all canister components have been carried out. The purpose has been to determine and develop the best manufacturing technique and to establish long-term contacts with the best suppliers of material and technology. Part of the work has involved the developing and implementing of a quality assurance system in accordance with ISO 9001, covering the whole chain from suppliers of material up to and including the delivery of assembled canisters. This report consists of a description of the design of the canister together with current drawings and complementary technical specifications stipulating, among other things, requirements placed on different materials. The different manufacturing methods that have been used are also described and commented on in both text and illustrations. For the manufacturing of copper tubes, the roll-forming of rolled plate to tube halves and longitudinal welding is a method that has been tested on a relatively large number of tubes by now, and that probably can be developed into a functioning production method. However, the very promising outcome of performed tests on seamless tube manufacturing, has resulted in a change in direction in tube manufacturing, focusing on continued testing of extrusion as well as pierce and draw processing in the immediate future. In connection with ongoing operations, new manufacturing tests of tubes with less material thickness will be carried out. Test manufacturing of cast inserts has resulted in the choice of nodular iron as material in the continued work. This improvement in design has resulted

  5. Test manufacturing of copper canisters with cast inserts. Assessment report

    International Nuclear Information System (INIS)

    The current design of canisters for the deep repository for spent nuclear fuel consists of an outer corrosion-protective copper casing in the form of a tubular section with lid and bottom and an inner pressure-resistant insert. The insert is designed to be manufactured by casting and inside are channels in which the fuel assemblies are to be placed. Over the last years, a number of full-scale manufacturing tests of all canister components have been carried out. The purpose has been to determine and develop the best manufacturing technique and to establish long-term contacts with the best suppliers of material and technology. Part of the work has involved the developing and implementing of a quality assurance system in accordance with ISO 9001, covering the whole chain from suppliers of material up to and including the delivery of assembled canisters. This report consists of a description of the design of the canister together with current drawings and complementary technical specifications stipulating, among other things, requirements placed on different materials. The different manufacturing methods that have been used are also described and commented on in both text and illustrations. For the manufacturing of copper tubes, the roll-forming of rolled plate to tube halves and longitudinal welding is a method that has been tested on a relatively large number of tubes by now, and that probably can be developed into a functioning production method. However, the very promising outcome of performed tests on seamless tube manufacturing, has resulted in a change in direction in tube manufacturing, focusing on continued testing of extrusion as well as pierce and draw processing in the immediate future. In connection with ongoing operations, new manufacturing tests of tubes with less material thickness will be carried out. Test manufacturing of cast inserts has resulted in the choice of nodular iron as material in the continued work. This improvement in design has resulted

  6. Ultrasound-guided central line insertion and standard peripherally inserted catheter placement in preterm infants: Comparing results from prospective study in a single-center

    Directory of Open Access Journals (Sweden)

    Dany Antanios Al Hamod

    2016-01-01

    Full Text Available Background: Among preterm infants, the peripherally inserted central catheter (PICC is the standard line for central venous access; however, its placement exposes them to hypothermia and pain. Ultrasound (US-guided central line insertion may be less morbid than standard PICC line. Aims: To determine the ease, success rate, and morbidity associated with US-guided central line insertion in the internal jugular vein (IJV by comparing it to the standard PICC line placement. Materials and Methods: This is a single-center nonrandomized prospective study evaluating preterm infants between October 2013 and June 2014. Patients were allocated into two groups: The standard group (control group who underwent blind PICC line insertion and the intervention group who underwent a percutaneous US-guided central line insertion in the IJV. The epicutaneo-cava-catheter was used in both groups. Results: Fifty neonates were enrolled on study. A statistically difference in favor of US-IJV insertion was noted concerning the rate of successful first attempt (P < 0.001, insertion (P = 0.001, and procedure duration (P < 0.001 and number of trials (P < 0.001 compared to PICC. No difference in complications (P = 1.000 was noted. Conclusion: US guided catheterization of the IJV technique is faster than PICC line insertion with higher rates of successful first attempt and insertion, less procedure duration and fewer number of trials compared to PICC line insertion. There were no differences in complications.

  7. Domain-specific languages

    OpenAIRE

    Jasný, Vojtěch

    2009-01-01

    The topic of the thesis are domain-specific languages (DSL) and their use in software development. The target audience are developers interested in learning more about this progressive area of software development. It starts with a necessary theoretical introduction to programming languages. Then, a classification of DSLs is given and software development methodologies based on DSLs are described, notably Language Oriented Programming and Intentional Programming. Another important piece in co...

  8. Implementing maritime domain awareness

    OpenAIRE

    Watts, Robert B.

    2006-01-01

    CHDS State/Local As an attempt to gain understanding of everything in the global maritime environment that can impact the security of the United States, the Maritime Domain Awareness initiative is one of the most ambitious projects ever undertaken by the U.S. government. Information that falls under the prevue of MDA is tremendously diverse and complex, having application in the regulatory, law enforcement, and military arenas. As such, MDA is a multi-agency effort that encompasses 16 resp...

  9. Tight attachment of chitin-binding-domain-tagged proteins to surfaces coated with acetylated chitosan.

    Science.gov (United States)

    Bernard, Michael P; Cao, Donghui; Myers, Rebecca V; Moyle, William R

    2004-04-15

    Several excellent procedures for trapping tagged proteins have been devised, but many of these are expensive, cannot be used outside a limited pH range, fail to work in the presence of chaotropic agents, or are difficult to use. The chitin binding domain (CBD) of Bacillus circulans chitinase, which binds to chitin matrices prepared from inexpensive reagents isolated from crab shells, is an alternative tag that can be used under a variety of pH and denaturing conditions. Kits based on the interaction between the CBD and the chitin beads are available commercially. Here, we show that simultaneous treatment of microtiter plates with chitosan, a deacetylated form of chitin, and acetic anhydride produces a surface-bound film of chitin that also interacts tightly with the CBD. Chitin-coated microtiter well plates captured a CBD-tagged heterodimeric human glycoprotein hormone analog directly from mammalian cell culture media, even when present in trace amounts. Binding to the surface was stable in sodium dodecylsulfate and reversed only partially at low pH or in 8M urea at 37 degrees C. This technique appears well suited to surface attachment and permits biochemical or other analyses of molecules that can be tagged with a CBD.

  10. On Free Z-domains%自由Z-domain

    Institute of Scientific and Technical Information of China (English)

    姚丽娟; 徐晓泉

    2011-01-01

    给出由偏序集生成的自由Z-domain,讨论自由Z-domain和偏序集的Dedekind-MacNeille完备化的一些性质.%The free Z-domains generated by posets are given.Some properties of tte free Z-domains and the Dedekind-MacNeille completions of posets are investigated.

  11. ALOG domains: provenance of plant homeotic and developmental regulators from the DNA-binding domain of a novel class of DIRS1-type retroposons

    Directory of Open Access Journals (Sweden)

    Iyer Lakshminarayan M

    2012-11-01

    Full Text Available Abstract Members of the Arabidopsis LSH1 and Oryza G1 (ALOG family of proteins have been shown to function as key developmental regulators in land plants. However, their precise mode of action remains unclear. Using sensitive sequence and structure analysis, we show that the ALOG domains are a distinct version of the N-terminal DNA-binding domain shared by the XerC/D-like, protelomerase, topoisomerase-IA, and Flp tyrosine recombinases. ALOG domains are distinguished by the insertion of an additional zinc ribbon into this DNA-binding domain. In particular, we show that the ALOG domain is derived from the XerC/D-like recombinases of a novel class of DIRS-1-like retroposons. Copies of this element, which have been recently inactivated, are present in several marine metazoan lineages, whereas the stramenopile Ectocarpus, retains an active copy of the same. Thus, we predict that ALOG domains help establish organ identity and differentiation by binding specific DNA sequences and acting as transcription factors or recruiters of repressive chromatin. They are also found in certain plant defense proteins, where they are predicted to function as DNA sensors. The evolutionary history of the ALOG domain represents a unique instance of a domain, otherwise exclusively found in retroelements, being recruited as a specific transcription factor in the streptophyte lineage of plants. Hence, they add to the growing evidence for derivation of DNA-binding domains of eukaryotic specific TFs from mobile and selfish elements.

  12. Insertion of the CMS coil into the barrel yoke on 14 September 2005

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    Insertion of the CMS coil into the barrel yoke on 14 September 2005. The pictures have been taken in the CMS experimental hall SX5 in Cessy, neighbouring France. The second picture shows the insertion of the Inner Vacuum Tank.

  13. Ultrasound-guided Central Line Insertion and Standard Peripherally Inserted Catheter Placement in Preterm Infants: Comparing Results from Prospective Study in a Single-center

    OpenAIRE

    Dany Antanios Al Hamod; Smart Zeidan; Ayah Al Bizri; Georges Baaklini; Yolla Nassif

    2016-01-01

    Background: Among preterm infants, the peripherally inserted central catheter (PICC) is the standard line for central venous access; however, its placement exposes them to hypothermia and pain. Ultrasound (US)-guided central line insertion may be less morbid than standard PICC line. Aims: To determine the ease, success rate, and morbidity associated with US-guided central line insertion in the internal jugular vein (IJV) by comparing it to the standard PICC line placement. Materials and Metho...

  14. External ear canal cholesteatoma after ventilation tube insertion and mastoidectomy

    Directory of Open Access Journals (Sweden)

    Đerić Dragoslava

    2012-01-01

    Full Text Available Introduction. Etiopathogenetically, there are two types of chollesteatomas: congenital, and acquired. Numerous theories in the literature try to explain the nature of the disease, however, the question about cholesteatomas remain still unanswered. The aim of the study was to present a case of external ear canal cholesteatoma (EEC developed following microsurgery (ventilation tube insertion and mastoidectomy, as well as to point ant possible mechanisms if its development. Case report. A 16-yearold boy presented a 4-month sense of fullness in the ear and otalgia on the left side. A year before, mastoidectomy and posterior atticotomy were performed with ventilation tube placement due to acute purulent mastoiditis. Diagnosis was based on otoscopy examination, audiology and computed tomography (CT findings. CT showed an obliterative soft-tissue mass completely filled the external ear canal with associated erosion of subjacent the bone. There were squamous epithelial links between the canal cholesteatoma and lateral tympanic membrane surface. They originated from the margins of tympanic membrane incision made for a ventilation tube (VT insertion. The position of VT was good as well as the aeration of the middle ear cavity. The tympanic membrane was intact and of normal appearance without middle ear extension or mastoid involvement of cholesteatoma. Cholesteatoma and ventilation tube were both removed. The patient recovered without complications and shortly audiology revealed hearing improving. Follow-up 2 years later, however, showed no signs of the disease. Conclusion. There could be more than one potential delicate mechanism of developing EEC in the ear with VT insertion and mastoidectomy. It is necessary to perform routine otologic surveillance in all patients with tubes. Affected ear CT scan is very helpful in showing the extent of cholesteatoma and bony defects, which could not be assessed by otoscopic examination alone.

  15. Caractéristiques syntaxiques de la parenthèse en latin : linéarisation, délimitation et insertion

    Directory of Open Access Journals (Sweden)

    Isabelle Charnavel

    2009-05-01

    Full Text Available Le but de cet article est d’analyser les règles syntaxiques du placement de l’incidente en latin. L’incidente – ou proposition parenthétique – présente en effet le paradoxe suivant : bien qu’autonome sur un plan structurel (elle forme une proposition indépendante, elle s’insère dans une autre phrase sur un plan syntagmatique (linéairement, elle se situe à l’intérieur d’une autre proposition, l’hôte. Nous proposons de considérer que, malgré son autonomie syntaxique, l’incidente obéit à des contraintes syntaxiques précises d’insertion.Tout d’abord, nous montrons que l’incidente, toujours continue, est délimitée sur ses bords gauche et droit, bien que dépourvue de marqueurs spécifiques : le changement de proposition marque le début de l’incidente, tandis que la reprise de la phrase hôte en montre la fin, au moyen de répétitions pouvant mener à des anacoluthes.En outre, nous montrons que la place de l’incidente dans la phrase hôte suit des règles spécifiques. Premièrement, les sites d’insertion sont contraints : ils se situent à la frontière des groupes fonctionnels de l’hôte. De plus, il existe des contraintes distributionnelles entre ces sites d’insertion. Nous proposons de considérer que le domaine de l’incidente correspond au(x constituant(s sur le(squel(s porte sémantiquement l’incidente et que celle-ci se place toujours à l’intérieur ou à la périphérie de son domaine : une incidente à une proposition indépendante se place en deuxième position de son domaine, tandis qu’une incidente à un constituant occupe la frontière droite de son domaine.The aim of the paper is to analyse the syntactic rules of the incidental clause in Latin: indeed, the incidental – i.e. parenthetical sentence - exhibits the following paradox: although it is independent from a structural viewpoint (it constitutes a main clause, it is inserted in another sentence from a syntagmatic

  16. Isolation and identification of chitinolytic strains and preliminary study on the antifungal activity of its crude chitinases%产几丁质酶菌的分离鉴定及其抑菌作用的初步研

    Institute of Scientific and Technical Information of China (English)

    檀建新; 陈忠义; 张杰; 黄大昉

    2001-01-01

    Several chitinolytic isolates were isolated from soil, sand, and water samples of Beijing. Among them the isolate CT14 was identified as Bacillus circulans that produced chitinase of the highest activity. The physiological characteristics of CT14, the morphological characteristics of CT14 cells and clones were studied. Its crude chitinases showed the inhibition against a wide-range of plant pathogenic fungi.%从北京地区的土样、砂样和水样中分离并纯化了产生几丁质酶的菌株,其中CT14含几丁质酶活性最高,经对其细胞形态、菌落特征的观察和生化特性检测,证明该菌株是环状芽孢杆菌(Bacillus circulans)。其几丁质酶粗提液能抑制多种植物病原真菌的生长,表明它对植物病原真菌的拮抗作用具有广谱性。

  17. Real-time RT-PCR expression analysis of chitinase and endoglucanase genes in the three-way interaction between the biocontrol strain Clonostachys rosea IK726, Botrytis cinera and strawberry

    DEFF Research Database (Denmark)

    Mamarabadi, Mojtaba; Jensen, Birgit; Jensen, Søren Dan Funck;

    2008-01-01

    Clonostachys rosea is a well-known biocontrol agent against Botrytis cinerea, the causal agent of gray mold in strawberry. The activity of cell wall-degrading enzymes might play a significant role for successful biocontrol by C. rosea. The expression pattern of four chitinases, and two endoglucan......Clonostachys rosea is a well-known biocontrol agent against Botrytis cinerea, the causal agent of gray mold in strawberry. The activity of cell wall-degrading enzymes might play a significant role for successful biocontrol by C. rosea. The expression pattern of four chitinases, and two...... endoglucanase genes from C. rosea strain IK726 was analyzed using real-time RT-PCR in vitro and in strawberry leaves during interaction with B. cinerea. Specific primers were designed for ß-tubulin genes from C. rosea and B. cinerea, respectively, and a gene encoding a DNA-binding protein (DBP) from strawberry......, allowing in situ activity assessment of each fungus in vitro and during their interaction on strawberry leaves. Growth of B. cinerea was inhibited in all pathogen-antagonist interactions while the activity of IK726 was slightly increased. In all in vitro interactions, four of the six genes were upregulated...

  18. Multiple functions of the von Willebrand Factor A domain in matrilins: secretion, assembly, and proteolysis

    Directory of Open Access Journals (Sweden)

    Kanbe Katsuaki

    2008-06-01

    Full Text Available Abstract The von Willebrand Factor A (vWF A domain is one of the most widely distributed structural modules in cell-matrix adhesive molecules such as intergrins and extracellular matrix proteins. Mutations in the vWF A domain of matrilin-3 cause multiple epiphyseal dysplasia (MED, however the pathological mechanism remains to be determined. Previously we showed that the vWF A domain in matrilin-1 mediates formation of a filamentous matrix network through metal-ion dependent adhesion sites in the domain. Here we show two new functions of the vWF A domain in cartilage-specific matrilins (1 and 3. First, vWF A domain regulates oligomerization of matrilins. Insertion of a vWF A domain into matrilin-3 converts the formation of a mixture of matrilin-3 tetramer, trimer, and dimer into a tetramer only, while deletion of a vWF A domain from matrilin-1 converts the formation of the native matrilin-1 trimer into a mixture of trimer and dimer. Second, the vWF A domain protects matrilin-1 from proteolysis. We identified a latent proteolytic site next to the vWF A2 domain in matrilin-1, which is sensitive to the inhibitors of matrix proteases. Deletion of the abutting vWF A domain results in degradation of matrilin-1, presumably by exposing the adjacent proteolytic site. In addition, we also confirmed the vWF A domain is vital for the secretion of matrilin-3. Secretion of the mutant matrilin-3 harbouring a point mutation within the vWF A domain, as occurred in MED patients, is markedly reduced and delayed, resulting from intracellular retention of the mutant matrilin-3. Taken together, our data suggest that different mutations/deletions of the vWF A domain in matrilins may lead to distinct pathological mechanisms due to the multiple functions of the vWF A domain.

  19. Effects of Laser Peripheral Iridotomy in Subgroups of Primary Angle Closure Based on Iris Insertion

    OpenAIRE

    Sung-Cheol Yun; Ji Wook Hong; Kyung Rim Sung; Jin Young Lee

    2015-01-01

    Purpose. To investigate the effect of laser peripheral iridotomy (LPI) in subgroups of primary angle closure based on iris insertion configuration. Methods. Anterior segment optical coherence tomography (AS-OCT) images were obtained before and two weeks after LPI. Qualitative classification of angle closure eyes according to iris insertion (basal insertion group (BG) and nonbasal insertion group (NBG)) was performed. Anterior chamber depth (ACD), lens vault (LV), iris curvature, iris area, ir...

  20. A proposed model membrane and test method for microneedle insertion studies

    OpenAIRE

    Larrañeta, Eneko; Moore, Jessica; Vicente-Pérez, Eva M.; González-Vázquez, Patricia; Lutton, Rebecca; Woolfson, A. David; Donnelly, Ryan F.

    2014-01-01

    A commercial polymeric film (Parafilm M®, a blend of a hydrocarbon wax and a polyolefin) was evaluated as a model membrane for microneedle (MN) insertion studies. Polymeric MN arrays were inserted into Parafilm M® (PF) and also into excised neonatal porcine skin. Parafilm M® was folded before the insertions to closely approximate thickness of the excised skin. Insertion depths were evaluated using optical coherence tomography (OCT) using either a force applied by a Texture Analyser or by a gr...

  1. Shotgun Cloning of Transposon Insertions in the Genome of Caenorhabditis elegans

    OpenAIRE

    Plasterk, Ronald H.A.; van der Linden, Alexander M.

    2006-01-01

    We present a strategy to identify and map large numbers of transposon insertions in the genome of Caenorhabditis elegans. Our approach makes use of the mutator strain mut-7, which has germline-transposition activity of the Tc1/mariner family of transposons, a display protocol to detect new transposon insertions, and the availability of the genomic sequence of C. elegans. From a pilot insertional mutagenesis screen, we have obtained 351 new Tc1 transposons inserted in or near 219 predicted C. ...

  2. Domain Engineering: An Empirical Study

    OpenAIRE

    Harris, Charles; Frakes, William B.

    2006-01-01

    This paper presents a summary and analysis of data gathered from thirteen domain engineering projects, participant surveys, and demographic information. Taking a failure modes approach, project data is compared to an ideal model of the DARE methodology, revealing valuable insights into points of failure in the domain engineering process. This study suggests that success is a function of the domain analyst’s command of a specific set of domain engineering concepts and skills, the time invested...

  3. A Convenient Category of Domains

    OpenAIRE

    Battenfeld, Ingo; Schröder, Matthias; Simpson, Alexander

    2007-01-01

    We motivate and define a category of topological domains, whose objects are certain topological spaces, generalising the usual ω-continuous dcppos of domain theory. Our category supports all the standard constructions of domain theory, including the solution of recursive domain equations. It also supports the construction of free algebras for (in)equational theories, can be used as the basis for a theory of computability, and provides a model of parametric polymorphism.

  4. A convenient category of domains

    OpenAIRE

    Battenfeld, Ingo; Schröder, Matthias; Simpson, Alex

    2007-01-01

    We motivate and define a category of "topological domains", whose objects are certain topological spaces, generalising the usual $omega$-continuous dcppos of domain theory. Our category supports all the standard constructions of domain theory, including the solution of recursive domain equations. It also supports the construction of free algebras for (in)equational theories, provides a model of parametric polymorphism, and can be used as the basis for a theory of computab...

  5. Online robust model estimation during in vivo needle insertions.

    Science.gov (United States)

    Barbé, Laurent; Bayle, Bernard; de Mathelin, Michel

    2006-01-01

    Soft tissue modeling is of key importance in medical robotics and simulation. In the case of percutaneous operations, a fine model of layers transitions and target tissues is required. However, the nature and the variety of these tissues is such that this problem is extremely complex. In this article, we propose a method to estimate the interaction between in vivo tissues and a surgical needle. The online robust estimation of a varying parameters model is achieved during an insertion in standard operating conditions. PMID:16404010

  6. TRACKER INSERTED INTO YB0 & HEAVY LOWERING COMPLETED

    CERN Multimedia

          The Tracker travelled very smoothly from Meyrin to Point 5 during the early hours of December 13th. Lowered later the same day, insertion was completed 18th December. The intense campaign of Tracker connections, involving 980 pipes, 2330 cables and 3623 fibre ribbons, has since begun and is making good progress. The final large element of CMS YE-1 was lowered gently into the cavern on January 22nd. This marks the end of fourteen months of heavy lowering operations.  

  7. Arbitrarily long distance quantum communication using inspection and power insertion

    Institute of Scientific and Technical Information of China (English)

    WANG WanYing; WANG Chuan; ZHANG GuangYu; LONG GuiLu

    2009-01-01

    The biggest obstacle for long distance quantum communication is the channel loss and the channel noise on photons. In this paper, a method to solve this problem was analyzed using inspection and power insertion (IPI). It is proved that quantum communication may be established over arbitrarily long distance using this technology. The amount of resources required is a polynomial function of the dis-tance. IPI is proposed as a general technique to prolong quantum secure direct communication where secret messages are transmitted directly over a quantum channel.

  8. The design and analysis of transposon insertion sequencing experiments.

    Science.gov (United States)

    Chao, Michael C; Abel, Sören; Davis, Brigid M; Waldor, Matthew K

    2016-02-01

    Transposon insertion sequencing (TIS) is a powerful approach that can be extensively applied to the genome-wide definition of loci that are required for bacterial growth under diverse conditions. However, experimental design choices and stochastic biological processes can heavily influence the results of TIS experiments and affect downstream statistical analysis. In this Opinion article, we discuss TIS experimental parameters and how these factors relate to the benefits and limitations of the various statistical frameworks that can be applied to the computational analysis of TIS data.

  9. Reverse genetics in Chlamydomonas: a platform for isolating insertional mutants

    Directory of Open Access Journals (Sweden)

    de Montaigu Amaury

    2011-07-01

    Full Text Available Abstract A method was developed to identify insertional mutants of Chlamydomonas reinhardtii disrupted for selected target genes. The approach relies on the generation of thousands of transformants followed by PCR-based screenings that allow for identification of strains harboring the introduced marker gene within specific genes of interest. Our results highlight the strengths and limitations of two independent screens that differed in the nature of the marker DNA used (PCR-amplified fragment containing the plasmid-free marker versus entire linearized plasmid with the marker and in the strategies used to maintain and store transformants.

  10. Cache Replacement Policy Using Map-based Adaptive Insertion

    OpenAIRE

    Ishii,Yasuo; Inaba, Mary; Hiraki, Kei

    2010-01-01

    International audience In this paper, we propose a map-based adaptive insertion policy (MAIP) for a novel cache replacement. The MAIP estimates the data reuse possibility on the basis of data reuse history. To track data reuse history, the MAIP employs a bitmap data structure, which we call memory access map. The memory access map holds all memory accessed locations in a fixed sized memory area to detect the data reuse. It can cover a large memory area that is compared to the size of a lar...

  11. Waveguide e-plane all-metal inserted diplexer

    OpenAIRE

    Rakić Milica; Jokanović Branka; Budimir Đ.

    2004-01-01

    This paper presents the procedure for designing a wave guide E-plane diplexer for Ku band with inserted metal septa. The diplexer is designed with filters of the fifth order and with T-junction in E-plane for the purpose of easier integration with microwave transceiver. The aim of this work is to master the design of a diplexer that should obtain 60 dB insulation between receiver and transmitter of a radio link and that will not need to be adjusted in serial production.

  12. Waveguide e-plane all-metal inserted diplexer

    Directory of Open Access Journals (Sweden)

    Rakić Milica

    2004-01-01

    Full Text Available This paper presents the procedure for designing a wave guide E-plane diplexer for Ku band with inserted metal septa. The diplexer is designed with filters of the fifth order and with T-junction in E-plane for the purpose of easier integration with microwave transceiver. The aim of this work is to master the design of a diplexer that should obtain 60 dB insulation between receiver and transmitter of a radio link and that will not need to be adjusted in serial production.

  13. A new gap separation mechanism for APS insertion devices.

    Energy Technology Data Exchange (ETDEWEB)

    Trakhtenberg, E. M.; Tcheskidov, V.; Den Hartog, P. K.; Deriy, B.; Erdmann, M.; Makarov, O.; Moog, E. R.

    1999-10-25

    A new gap separation mechanism for use with the standard Advanced Photon Source (APS) 3.3-cm-period undulator magnetic structures has been designed and built and the first system has been installed in the APS storage ring. The system allows a minimum magnetic gap of 10 mm for use with the APS 8-mm insertion device vacuum chambers. The mechanism is a bolted steel frame structure with a simple 4-motor mechanical drive train. The control system uses servomotors with incremental rotary encoders and virtual absolute linear encoders.

  14. An Empirical Evaluation of Probabilistic Lexicalized Tree Insertion Grammars

    CERN Document Server

    Hwa, R C

    1998-01-01

    We present an empirical study of the applicability of Probabilistic Lexicalized Tree Insertion Grammars (PLTIG), a lexicalized counterpart to Probabilistic Context-Free Grammars (PCFG), to problems in stochastic natural-language processing. Comparing the performance of PLTIGs with non-hierarchical N-gram models and PCFGs, we show that PLTIG combines the best aspects of both, with language modeling capability comparable to N-grams, and improved parsing performance over its non-lexicalized counterpart. Furthermore, training of PLTIGs displays faster convergence than PCFGs.

  15. Epidermolytic palmoplantar keratoderma due to a novel type of keratin mutation, a 3-bp insertion in the keratin 9 helix termination motif.

    Science.gov (United States)

    Coleman, C M; Munro, C S; Smith, F J; Uitto, J; McLean, W H

    1999-03-01

    Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant genodermatosis characterized by diffuse keratoderma, typically with an erythematous border. Histologically, palmoplantar epidermis shows suprabasal cytolysis and ultrastructurally, tonofilament aggregation with overlying epidermolytic hyperkeratosis. Mutations in the KRT9 gene, encoding keratin 9 (K9), a cytoskeletal protein expressed exclusively in suprabasal keratinocytes of palmoplantar epidermis, have been reported to cause EPPK. To date, all KRT9 defects reported in EPPK have been missense mutations in exon 1, which encodes the start of the alpha-helical rod domain. However, based on studies of other keratin disorders, it was postulated that mutations at the other end of the rod domain might also produce the EPPK phenotype. Here, we report the first mutation in the 2B domain of KRT9, 1362ins3, leading to an insertion of histidine in the helix termination motif of the K9 polypeptide. Insertional mutations have not been previously described in keratins. The phenotype of this case is similar to EPPK caused by 1A domain mutations, demonstrating that mutations in either of the helix boundary motif sequences of K9 are detrimental to keratin function and keratinocyte structure.

  16. Fc receptor endocytosis is controlled by a cytoplasmic domain determinant that actively prevents coated pit localization

    OpenAIRE

    1992-01-01

    Macrophages and B-lymphocytes express two major isoforms of Fc receptor (FcRII-B2 and FcRII-B1) that exhibit distinct capacities for endocytosis. This difference in function reflects the presence of an in- frame insertion of 47 amino acids in the cytoplasmic domain of the lymphocyte isoform (FcRII-B1) due to alternative mRNA splicing. By expressing wild type and mutant FcRII cDNAs in fibroblasts, we have now examined the mechanism by which the insertion acts to prevent coated pit localization...

  17. Domain Bridging Associations Support Creativity

    OpenAIRE

    Kötter, Tobias; Thiel, Kilian; Berthold, Michael R

    2010-01-01

    This paper proposes a new approach to support creativity through assisting the discovery of unexpected associations across different domains. This is achieved by integrating information from heterogeneous domains into a single network, enabling the interactive discovery of links across the corresponding information resources. We discuss three different pattern of domain crossing associations in this context.

  18. 21 CFR 872.3900 - Posterior artificial tooth with a metal insert.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Posterior artificial tooth with a metal insert... tooth with a metal insert. (a) Identification. A posterior artificial tooth with a metal insert is a... and metals of the platinum group intended to replace a natural tooth. The device is attached...

  19. Test of an element (power insertion) loaded by an internal explosion

    International Nuclear Information System (INIS)

    An element (power insertion) loaded by an internal explosion has been experimentally studied. The aim of tests is to study the deformation ability of a protective element-power steel-sand insertion. Data on radial migrations of the insertion after explosive loading have been obtained

  20. Metaphors, domains and embodiment

    Directory of Open Access Journals (Sweden)

    M.E. Botha

    2005-07-01

    Full Text Available Investigations of metaphorical meaning constitution and meaning (in- variance have revealed the significance of semantic and semiotic domains and the contexts within which they function as basis for the grounding of metaphorical meaning. In this article some of the current views concerning the grounding of metaphorical meaning in experience and embodiment are explored. My provisional agreement with Lakoff, Johnson and others about the “conceptual” nature of metaphor rests on an important caveat, viz. that this bodily based conceptual structure which lies at the basis of linguistic articulations of metaphor, is grounded in a deeper ontic structure of the world and of human experience. It is the “metaphorical” (actually “analogical” ontological structure of this grounding that is of interest for the line of argumentation followed in this article. Because Johnson, Lakoff and other’s proposal to ground metaphorical meaning in embodiment and neural processes is open to being construed as subjectivist and materialist, I shall attempt to articulate the contours of an alternative theory of conceptual metaphor, meaning and embodiment which counteracts these possibilities. This theory grounds metaphorical meaning and meaning change in an ontological and anthropological framework which recognises the presence and conditioning functioning of radially ordered structures for reality. These categorisations in which humankind, human knowledge and reality participate, condition and constrain (ground analogical and metaphorical meaning transfer, cross-domain mappings, and blends in cognition and in language, provide the basis for the analogical concepts found in these disciplines.

  1. The ATLAS Insertable B-Layer Detector (IBL)

    CERN Document Server

    Huegging, F; The ATLAS collaboration

    2010-01-01

    The upgrade for the ATLAS detector will undergo different phases towards SLHC. The first upgrade for the Pixel Detector will consist in the construction of a new pixel layer which will be installed during a longer shutdown of the LHC machine, the so-called Phase I Upgrade. The new detector, called Insertable B-Layer (IBL), will be inserted between the existing pixel detector and a new (smaller radius) beam-pipe at a radius of about 3.2 cm. The IBL requires the development of several new technologies to cope with the increase of radiation and pixel occupancy as well as to improve the physics performance of the existing pixel detector. In order to achieve these goals the pixel size is reduced and the material budget is minimized by using new lightweight mechanical support materials and a CO2 based cooling system. Main component of the module development for the IBL is the new ATLAS pixel readout chip, FE-I4, designed in 130 nm technology which features an array of 80 by 336 pixels with a pixel size of 50x250 µ...

  2. Fixed mask assembly research for APS insertion devices

    International Nuclear Information System (INIS)

    The Fixed Mask Assembly (FMA) is the first component to interact with the photon beam. Two sets of a pair of FMA channels, vertically and horizontally disposed, contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice, the FMA channels are made of heavy, seamless copper, have rectangular cross-sections, and are cooled internally with water. Channels are set at grazing angles ranging from 1 to 6 degrees with respect to the beam, depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAs. Therefore, a need exists to improve the FMA engineering, keeping in the mind the current design criteria and philosophy of FMAs. Preliminary analysis of current heat transfer practice indicates that the major resistance to heat transfer is on the coolant side. Therefore, FMA cooling would benefit from enhanced heat transfer on the coolant side. With this principle in mind, an experimental program has been undertaken to explore the feasibility of using high-performance copper tube configurations which are expected to yield heat transfer coefficients, ''h,'' in single phase flow systems 2 to 5(?) times higher than equivalent plain tubes. In this report, the experimental scope and a preliminary analysis of high-performance copper tube configurations are described

  3. Gastrostomy insertion: comparing the options - PEG, RIG or PIG?

    Energy Technology Data Exchange (ETDEWEB)

    Laasch, H.-U. E-mail: hul@smtr.nhs.uk; Wilbraham, L.; Bullen, K.; Marriott, A.; Lawrance, J.A.L.; Johnson, R.J.; Lee, S.H.; England, R.E.; Gamble, G.E.; Martin, D.F

    2003-05-01

    AIM: To compare percutaneous endoscopic gastrostomy (PEG) with radiologically inserted gastrostomy (RIG) and assess a hybrid gastrostomy technique (per-oral image-guided gastrostomy, PIG). MATERIALS AND METHODS: Fifty PEGs and 50 RIGs performed in three centres were prospectively compared and the endoscopic findings of 200 PEGs reviewed. A fluoroscopy-guided technique was modified to place 20 F over-the-wire PEG-tubes in 60 consecutive patients. RESULTS: Technical success was 98%, 100% and 100% for PEG, RIG and PIG, respectively. Antibiotic prophylaxis significantly reduced stoma infection for orally placed tubes (p=0.02). Ten out of 50 (20%) small-bore RIG tubes blocked. Replacement tubes were required in six out of 50 PEGs (12%), 10 out of 50 RIGs (20%), but no PIGs (p<0.001). No procedure-related complications occurred. The function of radiologically placed tubes was significantly improved with the larger PIG (p<0.001), with similar wound infection rates. PIG was successful in 24 patients where endoscopic insertion could not be performed. Significant endoscopic abnormalities were found in 42 out of 200 PEG patients (21%), all related to peptic disease. Insignificant pathology was found in 8.5%. CONCLUSION: PIG combines advantages of both traditional methods with a higher success and lower re-intervention rate. Endoscopy is unlikely to detect clinically relevant pathology other than peptic disease. PIG is a very effective gastrostomy method; it has better long-term results than RIG and is successful where conventional PEG has failed.

  4. Mass Insertions vs. Mass Eigenstates calculations in Flavour Physics

    CERN Document Server

    Dedes, A; Rosiek, J; Suxho, K; Tamvakis, K

    2015-01-01

    We present and prove a theorem of matrix analysis, the Flavour Expansion Theorem (or FET), according to which, an analytic function of a Hermitian matrix can be expanded polynomially in terms of its off-diagonal elements with coefficients being the divided differences of the analytic function and arguments the diagonal elements of the Hermitian matrix. The theorem is applicable in case of flavour changing amplitudes. At one-loop level this procedure is particularly natural due to the observation that every loop function in the Passarino-Veltman basis can be recursively expressed in terms of divided differences. FET helps to algebraically translate an amplitude written in mass eigenbasis into flavour mass insertions, without performing diagrammatic calculations in flavour basis. As a non-trivial application of FET up to a third order, we demonstrate its use in calculating strong bounds on the real parts of flavour changing mass insertions in the up- squark sector of the MSSM from neutron Electric Dipole Moment...

  5. Overview of the ATLAS Insertable B-Layer Pixel Detector

    CERN Document Server

    Pernegger, H; The ATLAS collaboration

    2011-01-01

    ATLAS currently develops a new pixel detector for the first upgrade of its tracking system: The ATLAS Insertable B-Layer Pixel detector (IBL). The new layer will be inserted between the inner most layer of the current pixel detector and a new beam pipe. The sensors are placed at a radius of 3.4cm. The expected high radiation levels and high hit occupancy require new developments for front-end chip and the sensor which can stand radiation levels beyond 5E15 neq/cm2. ATLAS has developed the new FEI4 and new silicon sensors to be used as pixel modules. Furthermore a new lightweight support and cooling structure was developed, which minimizes the overall radiation and allows detector cooling with CO2 at -40C coolant temperature. Currently the overall integration and installation procedure is being developed and test ready for installation in ATLAS in 2013. The presentation summarizes the current state of development of IBL modules, first preliminary test results of the new chip with new sensors, the construction ...

  6. End of the EM Barrel Presampler Construction and Insertion

    CERN Multimedia

    Hostachy, J.Y.

    The liquid argon barrel presampler is a thin detector placed in front of the electromagnetic barrel calorimeter, made up of two half barrels also, but with 32 sectors per half barrel instead of 16. Each of these 64 sectors is 3.1 m long, 28 cm large and 2.9 cm thick. Three countries took part in its construction: France (LPSC-Grenoble), Sweden (KTH-Stockholm) and Morocco (Hassan II Ain Chock-Casablanca and Mohamed V-Rabat universities, and CNESTEN-Rabat). The design of the presampler started 11 years ago and the series production began at the end of 2000. Cabling, mechanical and electronic tests of the anodes were achieved in Morocco. Forty-one sectors were assembled and validated at the LPSC-Grenoble and 25 at the KTH-Stockholm. In November 2002, the first half was inserted on the inner face of the first EM calorimeter wheel. The insertion of the other 32 sectors in the second EM calorimeter wheel was achieved in July 2003 (see pictures). The production of two additional sectors will allow us to study the p...

  7. A minimalist technique for insertion of intrauterine devices

    Directory of Open Access Journals (Sweden)

    Norman David Goldstuck

    2015-05-01

    Full Text Available The world’s population is approaching 7 billion. As a general rule, the countries with the highest population have the least available healthcare resources, the most notable exception being the United States of America (USA. Most of these countries have an urgent need to reduce their populations. The intrauterine device (IUD is used by the largest number of contraceptives world-wide and it has a proven record in reducing unwanted pregnancies. Its efficacy rate as a long-acting reversible contraceptive is matched only by subdermal implants which are not as cost effective. Although the rates of pelvic infection are elevated in many countries with low-resource health care systems, we now know that pelvic infection rates are independent of IUD usage. This is therefore no longer a contraindication for using IUDs on a large scale in family planning programs. The technique of IUD insertion as described in most textbooks and journals is unnecessarily complex and based on ritual rather than good clinical evidence. This is particularly interesting in that at a time where we prefer evidence based medicine there are still so many clinical practice sacred cows. This article advocates a simplification of the technique for inserting IUDs. The scientific rationale for simplifying the technique is presented, as well as evidence that it is as safe if not safer than the currently suggested methods, if used for the correct type of IUD acceptors.

  8. Single gene insertion drives bioalcohol production by a thermophilic archaeon

    Energy Technology Data Exchange (ETDEWEB)

    Basen, M; Schut, GJ; Nguyen, DM; Lipscomb, GL; Benn, RA; Prybol, CJ; Vaccaro, BJ; Poole, FL; Kelly, RM; Adams, MWW

    2014-12-09

    Bioethanol production is achieved by only two metabolic pathways and only at moderate temperatures. Herein a fundamentally different synthetic pathway for bioalcohol production at 70 degrees C was constructed by insertion of the gene for bacterial alcohol dehydrogenase (AdhA) into the archaeon Pyrococcus furiosus. The engineered strain converted glucose to ethanol via acetate and acetaldehyde, catalyzed by the host-encoded aldehyde ferredoxin oxidoreductase (AOR) and heterologously expressed AdhA, in an energy-conserving, redox-balanced pathway. Furthermore, the AOR/AdhA pathway also converted exogenously added aliphatic and aromatic carboxylic acids to the corresponding alcohol using glucose, pyruvate, and/or hydrogen as the source of reductant. By heterologous coexpression of a membrane-bound carbon monoxide dehydrogenase, CO was used as a reductant for converting carboxylic acids to alcohols. Redirecting the fermentative metabolism of P. furiosus through strategic insertion of foreign genes creates unprecedented opportunities for thermophilic bioalcohol production. Moreover, the AOR/AdhA pathway is a potentially game-changing strategy for syngas fermentation, especially in combination with carbon chain elongation pathways.

  9. Inserting Stress Analysis of Combined Hexagonal Aluminum Honeycombs

    Directory of Open Access Journals (Sweden)

    Xiangcheng Li

    2016-01-01

    Full Text Available Two kinds of hexagonal aluminum honeycombs are tested to study their out-of-plane crushing behavior. In the tests, honeycomb samples, including single hexagonal aluminum honeycomb (SHAH samples and two stack-up combined hexagonal aluminum honeycombs (CHAH samples, are compressed at a fixed quasistatic loading rate. The results show that the inserting process of CHAH can erase the initial peak stress that occurred in SHAH. Meanwhile, energy-absorbing property of combined honeycomb samples is more beneficial than the one of single honeycomb sample with the same thickness if the two types of honeycomb samples are completely crushed. Then, the applicability of the existing theoretical model for single hexagonal honeycomb is discussed, and an area equivalent method is proposed to calculate the crushing stress for nearly regular hexagonal honeycombs. Furthermore, a semiempirical formula is proposed to calculate the inserting plateau stress of two stack-up CHAH, in which structural parameters and mechanics properties of base material are concerned. The results show that the predicted stresses of three kinds of two stack-up combined honeycombs are in good agreement with the experimental data. Based on this study, stress-displacement curve of aluminum honeycombs can be designed in detail, which is very beneficial to optimize the energy-absorbing structures in engineering fields.

  10. Fracture of crystalline silicon nanopillars during electrochemical lithium insertion

    KAUST Repository

    Lee, S. W.

    2012-02-27

    From surface hardening of steels to doping of semiconductors, atom insertion in solids plays an important role in modifying chemical, physical, and electronic properties of materials for a variety of applications. High densities of atomic insertion in a solid can result in dramatic structural transformations and associated changes in mechanical behavior: This is particularly evident during electrochemical cycling of novel battery electrodes, such as alloying anodes, conversion oxides, and sulfur and oxygen cathodes. Silicon, which undergoes 400% volume expansion when alloying with lithium, is an extreme case and represents an excellent model system for study. Here, we show that fracture locations are highly anisotropic for lithiation of crystalline Si nanopillars and that fracture is strongly correlated with previously discovered anisotropic expansion. Contrary to earlier theoretical models based on diffusion-induced stresses where fracture is predicted to occur in the core of the pillars during lithiation, the observed cracks are present only in the amorphous lithiated shell. We also show that the critical fracture size is between about 240 and 360 nm and that it depends on the electrochemical reaction rate.

  11. Numerical Simulation of and Experiment on Electroforming Microstructure Mold Insert

    Science.gov (United States)

    Fu, Ming-Nan

    2008-09-01

    Microstructures are a vital component in various systems such as bionic chips, micro-fluidics sensor, optical communication systems, and micro-fuel cells. Micro-mold inserts should be produced by precise electroforming; however, interchanging the plating solution in an extremely small tunnel has been a main problem, where flow field and mass transfer are the major variances. In this paper we will concentrate on single- and three-micro hole array mode insert electroform flow fields and the mass transfer effect. Single-hole results show that the interchange of the plating fluid is more efficient at a lower aspect ratio of similar apertures with different aspect ratios. A lower coefficient of viscosities results in a weaker microelectroforming effect. The electroforming effect is better at an entry flow field speed of 0.01 m/s than at that of 0.001 m/s. The three-hole array results show that the first hole proved the best among the three holes, followed by the second hole; the third hole showed the worst results. The 10:1 ratio of distance to diameter of the hole produces better electroforming results than the 1:1 ratio. Lastly, this paper will contribute to the development of microelectro-mechanical manufacturing technologies.

  12. Gastrostomy insertion: comparing the options - PEG, RIG or PIG?

    International Nuclear Information System (INIS)

    AIM: To compare percutaneous endoscopic gastrostomy (PEG) with radiologically inserted gastrostomy (RIG) and assess a hybrid gastrostomy technique (per-oral image-guided gastrostomy, PIG). MATERIALS AND METHODS: Fifty PEGs and 50 RIGs performed in three centres were prospectively compared and the endoscopic findings of 200 PEGs reviewed. A fluoroscopy-guided technique was modified to place 20 F over-the-wire PEG-tubes in 60 consecutive patients. RESULTS: Technical success was 98%, 100% and 100% for PEG, RIG and PIG, respectively. Antibiotic prophylaxis significantly reduced stoma infection for orally placed tubes (p=0.02). Ten out of 50 (20%) small-bore RIG tubes blocked. Replacement tubes were required in six out of 50 PEGs (12%), 10 out of 50 RIGs (20%), but no PIGs (p<0.001). No procedure-related complications occurred. The function of radiologically placed tubes was significantly improved with the larger PIG (p<0.001), with similar wound infection rates. PIG was successful in 24 patients where endoscopic insertion could not be performed. Significant endoscopic abnormalities were found in 42 out of 200 PEG patients (21%), all related to peptic disease. Insignificant pathology was found in 8.5%. CONCLUSION: PIG combines advantages of both traditional methods with a higher success and lower re-intervention rate. Endoscopy is unlikely to detect clinically relevant pathology other than peptic disease. PIG is a very effective gastrostomy method; it has better long-term results than RIG and is successful where conventional PEG has failed

  13. Fixed mask assembly research for APS insertion devices

    International Nuclear Information System (INIS)

    The Fixed Mask Assembly (FMA) is the first component to interact with the photon beam. Two sets of a pair of FMA channels, vertically and horizontally disposed, contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice, the FMA channels are made of heavy, seamless copper, have rectangular cross-sections, and are cooled internally with water. Channels are set at grazing angles ranging from I to 6 degrees with respect to the beam, depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAS. Therefore, a need exists to improve the FMA engineering, keeping in mind the current design criteria and philosophy of FMAS. Preliminary analysis of current heat transfer practice indicates that the major resistance to heat transfer is on the coolant side. Therefore, FMA cooling would benefit from enhanced heat transfer on the coolant side. With this principle in mind, an experimental program has been undertaken to explore the feasibility of using high-performance copper tube configurations which are expected to yield heat transfer coefficients, open-quotes hclose quotes, in single phase flow systems 2 to 5(?) times higher than equivalent plain tubes. In this report, the experimental scope and a preliminary analysis of high-performance copper tube configurations are described

  14. QM/MM free-energy simulations of reaction in Serratia marcescens Chitinase B reveal the protonation state of Asp142 and the critical role of Tyr214.

    Science.gov (United States)

    Jitonnom, Jitrayut; Limb, Michael A L; Mulholland, Adrian J

    2014-05-01

    Serratia marcescens Chitinase B (ChiB), belonging to the glycosidase family 18 (GH18), catalyzes the hydrolysis of β-1,4-glycosidic bond, with retention of configuration, via an unusual substrate-assisted mechanism, in which the substrate itself acts as an intramolecular nucleophile. Here, both elementary steps (glycosylation and deglycosylation) of the ChiB-catalyzed reaction are investigated by means of combined quantum mechanics/molecular mechanics (QM/MM) umbrella sampling molecular dynamics (MD) simulations at the SCC-DFTB/CHARMM22 level of theory. We examine the influence of the Asp142 protonation state on the reaction and the role that this residue performs in the reaction. Our simulations show that reaction with a neutral Asp142 is preferred and demonstrate that this residue provides electrostatic stabilization of the oxazolinium ion intermediate formed in the reaction. Insight into the conformational itinerary ((1,4)B↔(4)H5↔(4)C1) adopted by the substrate (bound in subsite -1) along the preferred reaction pathway is also provided by the simulations. The relative energies of the stationary points found along the reaction pathway calculated with SCC-DFTB and B3LYP were compared. The results suggest that SCC-DFTB is an accurate method for estimating the relative barriers for both steps of the reaction; however, it was found to overestimate the relative energy of an intermediate formed in the reaction when compared with the higher level of theory. Glycosylation is suggested to be a rate-determining step in the reaction with calculated overall reaction free-energy barrier of 20.5 kcal/mol, in a reasonable agreement with the 16.1 kcal/mol barrier derived from the experiment. The role of Tyr214 in catalysis was also investigated with the results, indicating that the residue plays a critical role in the deglycosylation step of the reaction. Simulations of the enzyme-product complex were also performed with an unbinding event suggested to have been observed

  15. Directed Evolution of L-Aspartase by Mobility of Domains

    Institute of Scientific and Technical Information of China (English)

    GOU Xiao-jun; LI Shuang; KONG Xiang-duo; LIU Wei; SUN Yan-hong; ZHANG Jin

    2004-01-01

    To enhance the relative movement of domains, we inserted a random sequence of fifteen-peptide into the three domains of L-aspartase. By means of directed screening, the three isoforms of monomeric, dimmeric and tetrameric enzymes were obtained. Compared to the wild-type tetrameric L-asparease, these mutants remained 19.7%, 42.3%, and 92% of the enzyme activity, respectively. Moreover, the examination of enzyme properties revealed that their kcat and KM changed in varying degrees, and the optimum pH shifted towards acidic pH, while the dependence of the activity of enzyme on Mg2+ concentration and thermostability increased. Therefore this strategy provides a novel approach to directed evolution of enzymes.

  16. Ligand binding by PDZ domains

    DEFF Research Database (Denmark)

    Chi, Celestine N.; Bach, Anders; Strømgaard, Kristian;

    2012-01-01

    The postsynaptic density protein-95/disks large/zonula occludens-1 (PDZ) protein domain family is one of the most common protein-protein interaction modules in mammalian cells, with paralogs present in several hundred human proteins. PDZ domains are found in most cell types, but neuronal proteins......, for example, are particularly rich in these domains. The general function of PDZ domains is to bring proteins together within the appropriate cellular compartment, thereby facilitating scaffolding, signaling, and trafficking events. The many functions of PDZ domains under normal physiological as well...

  17. Current status of frameless anchored IUD for immediate intracesarean insertion.

    Science.gov (United States)

    Wildemeersch, Dirk; Goldstuck, Norman D; Hasskamp, Thomas

    2016-01-01

    Immediate postpartum intrauterine device (IUD) insertion deserves great attention as it can provide immediate, timely and convenient contraception plus the added benefit of preventing repeat unintended pregnancies. Although women post vaginal delivery can benefit from immediate post-placenta contraception, women undergoing Cesarean section clearly need contraception, as an inter-delivery interval shorter than 18 months places them at a high risk for uterine rupture. The main drawback of currently available framed IUD devices for immediate postpartum insertion of an IUD is their high expulsion and displacement rates when inserted immediately postpartum after both vaginal and Cesarean delivery. Current research suggests that a brief window of opportunity exists of 10 minutes for insertion of conventional IUDs after which time expulsion rates both immediately and over time are greatly enhanced. This paper summarizes the current research conducted to overcome the expulsion problems associated with conventional T-shaped devices as well as through the use of an anchored frameless device. In the 1970s and 1980s, attempts were made to solve the expulsion problem by modifying existing devices, such as adding absorbable sutures (Delta-T) or additional appendages. These attempts proved to be clinically unsuccessful as the catgut suture added to the transverse arms did not provide sufficient resistance to prevent downward displacement and expulsion. An anchoring technique to suspend a copper IUD to the fundus of the uterus was developed in Belgium in the 1980s and has been the subject of extensive ongoing clinical research since 1985. Recently the frameless copper releasing anchor IUD, GyneFix, has been tested for postplacental insertion. Initially, the anchor was modified by the inclusion of a biodegradable cone which was added below the anchoring knot. Clinical studies confirmed the adequacy of this approach suggesting that it was technically possible to anchor an IUD

  18. The framing of scientific domains

    DEFF Research Database (Denmark)

    Dam Christensen, Hans

    2014-01-01

    Purpose: By using the UNISIST models this article argues for the necessity of domain analysis in order to qualify scientific information seeking. The models better understanding of communication processes in a scientific domain and embraces the point that domains are always both unstable over time...... and changeable according to the specific perspective. This understanding is even more important today as numerous digitally generated information tools as well as collaborative and interdisciplinary research are blurring the domain borders. Nevertheless, researchers navigate “intuitively” in “their” specific...... as according to the agents that are charting them. As such, power in a Foucauldian sense is unavoidable in outlining a domain. Originality/value 1. The UNISIST models are applied to the domain of art history; and 2. the article discusses the instability of a scientific domain as well as, at the same time...

  19. Skin Blood Perfusion and Cellular Response to Insertion of Insulin Pen Needles With Different Diameters

    DEFF Research Database (Denmark)

    Præstmark, Kezia Ann; Stallknecht, Bente Merete; Bo Jensen, Casper;

    2014-01-01

    skin blood perfusion response around needle insertion sites. Three common sized pen needles of 28G, 30G, and 32G as well as hooked 32G needles, were inserted into the neck skin of pigs and then removed. Laser Speckle Contrast Analysis was used to measure skin blood perfusion for 20 minutes after...... the insertions. Seven pigs were included in the study and a total of 118 randomized needle insertions were conducted. Histology was made of tissue samples inserted with 18G, 28G, and 32G needles, and stained to quantify red and white blood cell response. Based on area under curve, calculated for each individual...

  20. Research on the Influence of Orthopaedic Inserts on Pressure Distribution in the Foot

    Directory of Open Access Journals (Sweden)

    Ignas Rutulys

    2011-02-01

    Full Text Available The article examines the influence of individual orthopaedic inserts on pressure distribution in the foot. Feet deformations, types of orthopaedic inserts, materials and pressure in the foot testing methods are discussed. Experimental computer measurements of pressure in the foot before and after the use of inserts have been done. During research, the inserts made of different kinds of materials selected according to human weight, pathology, skin sensitivity and many other reasons has been used. It has been determinated that orthopaedic inserts have a more noticeable impact on children whose feet is adjusted easier if compared with those of adults.Article in Lithuanian