Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization

Directory of Open Access Journals (Sweden)

Rakshit Amitava

2010-03-01

Full Text Available The effect of vesicular arbuscular mycorrhizal (VAM infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P were higher than in mycorrhized plants without added P or non-mycorrhized plants with added P. The amount of P in the soil samples from pots with mycorrhizal plants fertilized with P was evidently smaller than those in samples also fertilized non-mycorrhizal plants. The percentage of P was higher in tissues of fertilized mycorrhial plants than in those mycorrihzed plants without or nonmycorrhized plants with added low-soluble P. These results indicated that plants in VAM symbiosis mobilize P better from low-soluble P than non-mycorrhized plants.

VAM populations in relation to grass invasion associated with forest decline.

Science.gov (United States)

Vosatka, M; Cudlin, P; Mejstrik, V

1991-01-01

Spruce stands in Northern Bohemia forests, damaged to various degrees by industrial pollution, have shown establishment of grass cover following tree defoliation. Populations of vesicular-arbuscular mycorrhizal (VAM) fungi were studied under this grass cover in four permanent plots with spruce under different levels of pollution stress. Soil and root samples were collected in April and June within each plot as follows: (1) sites without grass, (2) sites with initial stages of grass invasion, and (3) sites with fully developed grass cover. In all plots, the highest number of propagules were recovered from samples taken from sites having full grass cover. Mycorrhizal infection of grass was highest in the plot with the severest pollution damage and lowest in the least damaged plot. The development of grass cover and VAM infection of grass increased with tree defoliation caused by air pollution.

Rheology enhancement for remediated PX6 melter feed

International Nuclear Information System (INIS)

Marek, J.C.; Eibling, R.E.

1996-01-01

This document is referenced in WSRC-TR-94-0556. This memorandum summarizes results of experimental work performed on the original IDMS PX6 melter feed, the remediated IDMS PX6 melter feed, and melter feeds produced in a laboratory simulation to duplicate the IDMS remediation as well as the experimental results on the caustic treatment to enhance the rheology. Characterization of the products of excess caustic addition and what steps to take if excess caustic is inadvertently added to the IDMS PX6 melter feed are also discussed

Internal Indpendent Assessment Report - CASTLE-PX SQA

Energy Technology Data Exchange (ETDEWEB)

Whitney, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dancy, L. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pope, V. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-04-01

This IIA assessed the flow down of institutional 830 Software Quality Assurance requirements through three required document templates to the CASTLE-PX software effort and the implementation of those SQA requirements. The templates flow down the DOE O 414.1D consensus standard requirements for Safety Software. This assessment did not include the flow down of NAP-24, Weapon Quality Policy, requirements. The assessment focused on the CASTLE-PX project’s software development and release processes. It did not assess Pantex’s acceptance or usage of the software. The assessment resulted in 3 Deficiencies, 5 Observations, 1 Recommendation, and 3 Strengths. Overall the CASTLE-PX team demonstrated it values quality and has worked to integrate quality practices into its software development processes. Improvement in documentation will enhance their SQA implementation.

Value Adding Management (VAM) of buildings and facility services in four steps

NARCIS (Netherlands)

van der Voordt, Theo; Hoendervanger, Jan Gerard; Jensen, Per Anker; Bergsma, Feike

2016-01-01

This paper presents a new Value Adding Management (VAM) model that aims to support decision makers in identifying appropriate interventions in buildings, other facilities and services that add value to the organisation, to manage its implementation, and to measure the output and outcomes. The paper

Changes of blood levels of LPO, SOD and GSH-Px after endovenous laser treatment of varicose greater saphenous vein

International Nuclear Information System (INIS)

Han Li'na; Gu Ying; Liu Fanguang

2004-01-01

Objective: To investigate the changes of the blood levels of lipid peroxide (LPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) after treatment of varicose greater saphenous vein with either endovenous laser or conventional surgery (high ligation plus stripping). Methods: Thirty-seven patients with varicose greater saphenous vein were treated with endovenous laser and another 33 patients were treated with conventional surgery. Levels of LPO (serum, with TBA fluorescein), SOD (whole blood, with RIA) and GSH-Px (whole blood, with direct DTNB) were determined in these patients both before and 1, 3, 5, 7, 10, 15 days after treatment. Levels in 30 controls were also measured. Results: The levels of LPO were higher and levels of SOD, GSH-Px lower in the patients than those in the controls. After either form of therapy, the levels LPO rose and levels of SOD, GSH-Px dropped immediately but gradually approached the control values by the 15 th day (slower with SOD and GSH-Px). However, the early increase of LPO levels were less and recovery sooner in the group of patients treated with laser. Conclusion: Changes of levels of LPO, SOD and GSH-Px were closely related to the degree of stress and recovery condition after the treatment

Exergy Analysis of a Two-Pass Reverse Osmosis (RO Desalination Unit with and without an Energy Recovery Turbine (ERT and Pressure Exchanger (PX

Directory of Open Access Journals (Sweden)

Nuri M. Eshoul

2015-07-01

Full Text Available This paper presents an exergy analysis of an actual two-pass (RO desalination system with the seawater solution treated as a real mixture and not an ideal mixture. The actual 127 ton/h two pass RO desalination plant was modeled using IPSEpro software and validated against operating data. The results show that using the (ERT and (PX reduced the total power consumption of the SWRO desalination by about 30% and 50% respectively, whereas, the specific power consumption for the SWRO per m3 water decreased from 7.2 kW/m3 to 5.0 kW/m3 with (ERT and 3.6 kW/m3 with (PX. In addition, the exergy efficiency of the RO desalination improved by 49% with ERT and 77% with PX and exergy destruction was reduced by 40% for (ERT and 53% for (PX. The results also showed that, when the (ERT and (PX were not in use, accounted for 42% of the total exergy destruction. Whereas, when (ERT and (PX are in use, the rejected seawater account maximum is 0.64%. Moreover, the (PX involved the smallest area and highest minimum separation work.

Role of VAM on growth and phosphorus nutrition of maize with low soluble phosphate fertilization Efecto de la infestación con micorrizas vesiculo arbusculares (VAM en plantas de Zea mays fertilizadas con dosis bajas de fósforo

Directory of Open Access Journals (Sweden)

Amitava Rakshit

2010-01-01

Full Text Available The effect of vesicular arbuscular mycorrhizal (VAM infection on growth and P nutrition in Maize (Zea mays, cv.DDH hybrid were assessed in Oxisol pot experiment. Maize was grown inoculated with spores of VAM fungi Glomus mosseae or non-inoculated. Low soluble ferrous phosphate (FePO4.4H2O was added to the mycorrhized and non-micrrohized maized. The dry weight of mycorrhized plants with added phosphate (P were higher than in mycorrhized plants without added P or non-mycorrhized plants with added P. The amount of P in the soil samples from pots with mycorrhizal plants fertilized with P was evidently smaller than those in samples also fertilized non-mycorrhizal plants. The percentage of P was higher in tissues of fertilized mycorrhial plants than in those mycorrihzed plants without or nonmycorrhized plants with added low-soluble P. These results indicated that plants in VAM symbiosis mobilize P better from low-soluble P than non-mycorrhized plants.En condiciones de casa de malla se evaluó el efecto de la infestación con micorrizas vesículo arbusculares (VAM en la asimilación de P por plantas de maíz (Zea mays, cv.DDH hybrid cultivadas en un Oxisol. Como micorriza se utilizó el hongo Glomus mosseae. En ambos tratamientos (con micorriza y sin ella se aplicó fosfato ferroso (FePO4.4H2O. La producción de MS de maíz fue mayor cuando se aplicaron el hongo + la fuente de P. La cantidad de P en el suelo con este tratamiento fue menor que en el suelo fertilizado pero sin aplicación del hongo. En las hojas de las plantas las mayores concentraciones de P se observaron igualmente en el tratamiento micorriza + aplicación de fertilizante.

Structure determination and compositional modification of body-centered tetragonal PX-phase lead titanate

Czech Academy of Sciences Publication Activity Database

Wang, J.; Schenk, K.; Carvalho, A.; Wylie-van Eerd, B.; Trodahl, J.; Sandu, C.S.; Bonin, M.; Gregora, Ivan; He, Z.; Yamada, T.; Funakubo, H.; Briddon, P.R.; Setter, N.

2011-01-01

Roč. 23, č. 10 (2011), s. 2529-2535 ISSN 0897-4756 R&D Projects: GA AV ČR KAN301370701 Institutional research plan: CEZ:AV0Z10100520 Keywords : lead titanate * fibrous PX phase * structure determination * open channels * Raman scattering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.286, year: 2011

Quantum phase diagram of the integrable px+ipy fermionic superfluid

DEFF Research Database (Denmark)

Rombouts, Stefan; Dukelsky, Jorge; Ortiz, Gerardo

2010-01-01

transition, separating a strong-pairing from a weak-pairing phase. The mean-field solution allows to connect these results to other models with px+ipy pairing order. We define an experimentally accessible characteristic length scale, associated with the size of the Cooper pairs, that diverges......We determine the zero-temperature quantum phase diagram of a px+ipy pairing model based on the exactly solvable hyperbolic Richardson-Gaudin model. We present analytical and large-scale numerical results for this model. In the continuum limit, the exact solution exhibits a third-order quantum phase...... at the transition point, indicating that the phase transition is of a confinement-deconfinement type without local order parameter. We propose an experimental measurement to detect the transition. We show that this phase transition is not limited to the px+ipy pairing model but can be found in any representation...

PX-18 Protects Human Saphenous Vein Endothelial Cells under Arterial Blood Pressure.

Science.gov (United States)

Kupreishvili, Koba; Stooker, Wim; Emmens, Reindert W; Vonk, Alexander B A; Sipkens, Jessica A; van Dijk, Annemieke; Eijsman, Leon; Quax, Paul H; van Hinsbergh, Victor W M; Krijnen, Paul A J; Niessen, Hans W M

2017-07-01

Arterial blood pressure-induced shear stress causes endothelial cell apoptosis and inflammation in vein grafts after coronary artery bypass grafting. As the inflammatory protein type IIA secretory phospholipase A 2 (sPLA 2 -IIA) has been shown to progress atherosclerosis, we hypothesized a role for sPLA 2 -IIA herein. The effects of PX-18, an inhibitor of both sPLA 2 -IIA and apoptosis, on residual endothelium and the presence of sPLA 2 -IIA were studied in human saphenous vein segments (n = 6) perfused at arterial blood pressure with autologous blood for 6 hrs. The presence of PX-18 in the perfusion blood induced a significant 20% reduction in endothelial cell loss compared to veins perfused without PX18, coinciding with significantly reduced sPLA 2 -IIA levels in the media of the vein graft wall. In addition, PX-18 significantly attenuated caspase-3 activation in human umbilical vein endothelial cells subjected to shear stress via mechanical stretch independent of sPLA 2 -IIA. In conclusion, PX-18 protects saphenous vein endothelial cells from arterial blood pressure-induced death, possibly also independent of sPLA 2 -IIA inhibition. Copyright © 2017 Elsevier Inc. All rights reserved.

PX-RICS-deficient mice mimic autism spectrum disorder in Jacobsen syndrome through impaired GABAA receptor trafficking.

Science.gov (United States)

Nakamura, Tsutomu; Arima-Yoshida, Fumiko; Sakaue, Fumika; Nasu-Nishimura, Yukiko; Takeda, Yasuko; Matsuura, Ken; Akshoomoff, Natacha; Mattson, Sarah N; Grossfeld, Paul D; Manabe, Toshiya; Akiyama, Tetsu

2016-03-16

Jacobsen syndrome (JBS) is a rare congenital disorder caused by a terminal deletion of the long arm of chromosome 11. A subset of patients exhibit social behavioural problems that meet the diagnostic criteria for autism spectrum disorder (ASD); however, the underlying molecular pathogenesis remains poorly understood. PX-RICS is located in the chromosomal region commonly deleted in JBS patients with autistic-like behaviour. Here we report that PX-RICS-deficient mice exhibit ASD-like social behaviours and ASD-related comorbidities. PX-RICS-deficient neurons show reduced surface γ-aminobutyric acid type A receptor (GABAAR) levels and impaired GABAAR-mediated synaptic transmission. PX-RICS, GABARAP and 14-3-3ζ/θ form an adaptor complex that interconnects GABAAR and dynein/dynactin, thereby facilitating GABAAR surface expression. ASD-like behavioural abnormalities in PX-RICS-deficient mice are ameliorated by enhancing inhibitory synaptic transmission with a GABAAR agonist. Our findings demonstrate a critical role of PX-RICS in cognition and suggest a causal link between PX-RICS deletion and ASD-like behaviour in JBS patients.

Laccase 1 gene from Plutella xylostella (PxLac1) and its functions in humoral immune response.

Science.gov (United States)

Wang, Ze-Hua; Hu, Rong-Min; Ye, Xi-Qian; Huang, Jian-Hua; Chen, Xue-Xin; Shi, Min

Laccase (EC 1.10.3.2) is a phenoloxidase found in many insect species. The Laccase 1 gene from Plutella xylostella (PxLac1) was cloned, and its expression patterns and functions were determined using qPCR and RNAi methods. The results showed that the expression levels of PxLac1 were consistently high in all larval stages, and the most abundant was in the midgut during the 4th instar stage. Moreover, the expression of PxLac1 was up-regulated in response to bacterial infection, and decreased 24 h after being parasitized by Cotesia vestalis. Further analyses indicated that the effect of parasitization on PxLac1 was induced by active C. vestalis Bracovirus (CvBV). Haemocyte-free hemolymph phenoloxidase (PO) activity was suppressed when PxLac1 was treated with RNAi. Our results provide evidence for a connection between the Laccase 1 gene and insect immunity, and revealed that parasitoid polydnavirus suppresses host PO activity via PxLac1 regulation. Copyright © 2018. Published by Elsevier Ltd.

Full-scale demonstration of treatment of mechanically separated organic residue in a bioreactor at VAM in Wijster

NARCIS (Netherlands)

Oonk, H.; Woelders, H.

1999-01-01

At the VAM waste treatment company in Wijster a demonstration is in progress of bioreactor technology for the treatment of mechanically separated organic residue (MSOR) of a waste separation plant. This bioreactor is an in situ fermentation cell in which physical, chemical and biological processes

Crystallography beyond Crystals: PX and SPCryoEM

Indian Academy of Sciences (India)

IAS Admin

This article describes how PX and SPCryoEM are independent methods, .... used by crystallographers working in areas such as biology, chemistry, materials science, physics, and geology .... drop of solution 3.5 µL typically is applied on the grid and blotted ..... cians, physicists, engineers and architects, none of the progress.

Down-regulation of hTERT and Cyclin D1 transcription via PI3K/Akt and TGF-β pathways in MCF-7 Cancer cells with PX-866 and Raloxifene

Energy Technology Data Exchange (ETDEWEB)

Peek, Gregory W. [Department of Biology, University of Alabama at Birmingham, Birmingham, AL (United States); Tollefsbol, Trygve O., E-mail: trygve@uab.edu [Department of Biology, University of Alabama at Birmingham, Birmingham, AL (United States); Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL (United States); Comprehensive Center for Healthy Aging, University of Alabama at Birmingham, Birmingham, AL (United States); Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL (United States); Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL (United States)

2016-05-15

Human telomerase reverse transcriptase (hTERT) is the catalytic and limiting component of telomerase and also a transcription factor. It is critical to the integrity of the ends of linear chromosomes and to the regulation, extent and rate of cell cycle progression in multicellular eukaryotes. The level of hTERT expression is essential to a wide range of bodily functions and to avoidance of disease conditions, such as cancer, that are mediated in part by aberrant level and regulation of cell cycle proliferation. Value of a gene in regulation depends on its ability to both receive input from multiple sources and transmit signals to multiple effectors. The expression of hTERT and the progression of the cell cycle have been shown to be regulated by an extensive network of gene products and signaling pathways, including the PI3K/Akt and TGF-β pathways. The PI3K inhibitor PX-866 and the competitive estrogen receptor ligand raloxifene have been shown to modify progression of those pathways and, in combination, to decrease proliferation of estrogen receptor positive (ER+) MCF-7 breast cancer cells. We found that combinations of modulators of those pathways decreased not only hTERT transcription but also transcription of additional essential cell cycle regulators such as Cyclin D1. By evaluating known expression profile signatures for TGF-β pathway diversions, we confirmed additional genes such as heparin-binding epidermal growth factor-like growth factor (HB EGF) by which those pathways and their perturbations may also modify cell cycle progression. - Highlights: • PX-866 and raloxifene affect the PI3K/Akt and TGF-β pathways. • PX-866 and raloxifene down-regulate genes up-regulated in cancer. • PX-866 and raloxifene decrease transcription of hTERT and Cyclin D1. • Pathological transcription signatures can identify new defense mechanisms.

Protein crystallography beamline (PX-BL21); its utilization and research highlights

International Nuclear Information System (INIS)

Kumar, Ashwani; Ghosh, Biplab; Singh, Rahul; Makde, Ravindra; Sharma, Surinder M.

2016-01-01

The protein crystallography beamline (PX-BL21) is sourced on 1.5 T bending magnet of 2.5 GeV Indus-2 synchrotron. This beamline has been designed to perform monochromatic and anomalous diffraction experiments on single crystals of biological macromolecules such as protein, DNA and their complexes. PX beamline also has a state-of-art ancillary biochemical laboratory to prepare single crystals of biological macromolecules. Since the commissioning of the beamline, it has been utilized by more than 70% of research groups working in the area of protein crystallography in India. About 30 crystal structures of proteins, determined using this beamline, have been deposited in Protein Data Bank (PDB). Some of these structures have been determined using experimental phasing, such as the single wavelength anomalous diffraction (SAD) experiments. The energy tunability of the synchrotron have been exploited to carry our various SAD experiments: Selenium-SAD, Zinc-SAD and Manganese-SAD and Sulphar-SAD. In the present talk, the key results from the PX-BL21 beamline will be discussed. (author)

Roles of viral and cellular proteins in the expression of alternatively spliced HTLV-1 pX mRNAs

International Nuclear Information System (INIS)

Princler, Gerald L.; Julias, John G.; Hughes, Stephen H.; Derse, David

2003-01-01

The human T cell leukemia virus type 1 (HTLV-1) genome contains a cluster of at least five open reading frames (ORFs) near the 3' terminus within the pX region. The pX ORFs are encoded by mono- or bicistronic mRNAs that are generated by alternative splicing. The various pX mRNAs result from skipping of the internal exon (2-exon versus 3-exon isofoms) or from the utilization of alternative splice acceptor sites in the terminal exon. The Rex and Tax proteins, encoded by ORFs X-III and X-IV, have been studied intensively and are encoded by the most abundant of the alternative 3-exon mRNAs. The protein products of the other pX ORFs have not been detected in HTLV-1-infected cell lines and the levels of the corresponding mRNAs have not been accurately established. We have used real-time RT-PCR with splice-site specific primers to accurately measure the levels of individual pX mRNA species in chronically infected T cell lines. We have asked whether virus regulatory proteins or ectopic expression of cellular factors influence pX mRNA splicing in cells that were transfected with HTLV-1 provirus clones. In chronically infected cell lines, the pX-tax/rex mRNA was present at 500- to 2500-fold higher levels than the pX-tax-orfII mRNA and at approximately 1000-fold higher levels than pX-rex-orfI mRNA. Chronically infected cell lines that contain numerous defective proviruses expressed 2-exon forms of pX mRNAs at significantly higher levels compared to cell lines that contain a single full-length provirus. Cells transfected with provirus expression plasmids expressed similar relative amounts of 3-exon pX mRNAs but lower levels of 2-exon mRNA forms compared to cells containing a single, full-length provirus. The pX mRNA expression patterns were nearly identical in cells transfected with wild-type, Tax-minus, or Rex-minus proviruses. Cotransfection of cells with HTLV-1 provirus in combination with SF2/ASF expression plasmid resulted in a relative increase in pX-tax/rex m

Implementation of innovative pulsed xenon ultraviolet (PX-UV environmental cleaning in an acute care hospital

Directory of Open Access Journals (Sweden)

Fornwalt L

2014-01-01

Full Text Available Lori Fornwalt,1 Brad Riddell1,2 1Departments of Infection Prevention and Environmental Services, Trinity Medical Centre, Birmingham, AL, 2Environmental Services, Medical University of South Carolina, Charleston, SC, USA Abstract: It is widely acknowledged that the hospital environment is an important reservoir for many of the pathogenic microbes associated with health care-associated infections (HAIs. Environmental cleaning plays an important role in the prevention and containment of HAIs, in patient safety, and the overall experience of health care facilities. New technologies, such as pulsed xenon ultraviolet (PX-UV light systems are an innovative development for enhanced cleaning and decontamination of hospital environments. A portable PX-UV disinfection device delivers pulsed UV light to destroy microbial pathogens and spores, and can be used in conjunction with manual environmental cleaning. In addition, this technology facilitates thorough disinfection of hospital rooms in 10–15 minutes. The current study was conducted to evaluate whether the introduction of the PX-UV device had a positive impact on patient satisfaction. Satisfaction was measured using the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS survey. In 2011, prior to the introduction of the PX-UV system, patient HCAHPS scores for cleanliness averaged 75.75%. In the first full quarter after enhanced cleaning of the facility was introduced, this improved to 83%. Overall scores for the hospital rose from 76% (first quarter, 2011 to 87.6% (fourth quarter, 2012. As a result of this improvement, the hospital received 1% of at-risk reimbursement from the inpatient prospective payment system as well as additional funding. Cleanliness of the hospital environment is one of the questions included in the HCAHPS survey and one measure of patient satisfaction. After the introduction of the PX-UV system, the score for cleanliness and the overall rating of the

MDA and GSH-Px activity in transition dairy cows under seasonal variations and their relationship with reproductive performance

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Colakoglu Hatice Esra

2017-12-01

Full Text Available Introduction: The purpose of the current study was to evaluate the blood glutathione peroxidase (GSH-Px and malondialdehyde (MDA levels under seasonal variations in dairy cows during transition period, and to assess the relationship between chosen reproductive parameters, GSH-Px, and MDA.

Hesiod and Hávamál: Transitions and the Transmission of Wisdom

Directory of Open Access Journals (Sweden)

Lilah Grace Canevaro

2014-03-01

Full Text Available This article offers fresh insights into Hesiod’s Works and Days by comparing it with the Eddic Hávamál, a didactic poem far removed in terms of geography and date, but compellingly close in subject matter, construction, and transmission. It finds parallels between the poems in the methods of teaching and in what is being taught, focusing on the shared theme of self-sufficiency (both intellectual and practical. It finds parallels in structure, as Hávamál is, like the Works and Days, made up not only of precepts and maxims but also of elaborate mythological sections, and is associated with catalogic elements which may be original or later accretions, just like Hesiod’s Days, or the Catalogue of Women, or the Ornithomanteia. This article also traces parallel scholarly trajectories, exploring the strikingly similar histories of scholarship on the two poems. Finally, this paper finds parallels in the transmission of the poems, as both are rooted in the oral tradition but poised at a crucial juncture: the advent of writing. Despite the striking similarities between the poems, this paper refrains from any suggestion of a straight channel of reception but rather interprets the parallels as a reflection of comparable societies, or at least societies at comparable points in their developments. Archaic Greece and Viking Scandinavia might not be exactly parallel cultures, but they evidently share certain cultural concerns: as agrarian societies with strong family and household structures, polytheistic religions and honor codes, they offer similar advice in similar formulations through similar didactic strategies. Such similarities may encourage us to think in terms of the shared characteristics of transitional products. If we exclude direct reception we are left with a cultural constant: the transmission of wisdom. And with recurring elements such as gnomic language, myth and catalogue, we are also left with constant expressions of that wisdom.

CONTROL OF “DAMPING OFF” DISEASE CAUSED BY Sclerotium rolfsii SACC. USING ACTINOMYCETES AND VAM FUNGI ON SOYBEAN IN THE DRY LAND BASED ON MICROORGANISM DIVERSITY OF RHIZOSPHERE ZONE

Directory of Open Access Journals (Sweden)

Ika Rochdjatun Sastrahidayat

2011-02-01

Full Text Available One of the obstacles in the efforts to increase soybean production in Indonesia is disease such as damping off which is caused by Sclerotium rolfsii. In East Java, the intensity of S. Rolfsii reached approximately 8.61% that spread all over Indonesia region, even in our neighbor countries such as Malaysia, Thailand and the Philippines. This research was carried out to determine the efficacy of Actinomycetes and VAM (Vesicular Arbuscular Mycorrhizal against damping-off attack and the diversity of micro-organisms in rhizosfer. Research conducted in the laboratory and screen house on Plant Protection Department, Faculty of Agriculture, University of Brawijaya and in Lawang District Malang. Observation variables include level of pathogen attack and infection rate of damping-off pathogen. Plant height, number of pods, pod weight, seed weight and weight of 100 seeds from each treatment, diversity and identification of microorganisms in rhizosphere were also observed. The results showed that Actinomycetes and VAM application could decrease the percentage of plant death due to damping-off. Application of Actinomycetes and VAM gave effect on microorganism diversity of Ratai Rhizosphere but not on Wilis.

Aggregation of surface mine soil by interaction between VAM fungi and lignin degradation products of lespedeza

Energy Technology Data Exchange (ETDEWEB)

Rothwell, F.M. (USDA Forest Service, Berea, KY (USA). Northeastern Forest Experiment Station, Forestry Sciences Laboratory)

1984-01-01

The external mycelium of a vesicular-arbuscular mycorrhizal (VAM) fungus was effective in aggregating a sandy loam minesoil. The polysaccharide nature of the soil binding agent on hyphal surfaces and on the surfaces of sand particles in contact with the hyphae within the aggregate was demonstrated with the periodic acid-Schiff reagent staining reaction. A possible stabilizing mechanism for macroaggregates was proposed that involves a coupling reaction between glucosamines in the hyphal walls of the fungus with phenolic compounds released during lignin degradation of sericea lespedeza root tissue. 28 refs.

Effect of high levels of organic selenium on glutation-peroxidase (GSH-Px activity in blood plasma of broilers

Directory of Open Access Journals (Sweden)

Joksimović-Todorović Mirjana

2005-01-01

Full Text Available An experiment lasting 45 days was performed on 125 Hybro broilers divided into five groups. All compounds for broiler feed mixes used in the experiment contained 0.15 mg Se/kg, in the form of sodium selenite. The control group (K-group of broilers was fed mixes without added organic selenium, and the experimental groups with mixes to which selenium, in the form of selenized-yeast, was added in quantities of 2, 5, 10, or 15 mg/kg. Selenized yeast (ICN - Gaienika was obtained from beer yeast and contained 1.51, or 1.45 mg/g total, or organically bound selenium. At the beginning of the fattening period, GSH-Px plasma activity in broilers of the K-group ranged around 16.55 μkat/L, while GSH-Px plasma activity in broilers of experimental groups was statistically significantly higher, but without any major differences among the individual groups (on the average 25.53fjkat/L. In the blood plasma of K-group, GSH-Px activity dropped already in the second week of life and was maintained at a relatively constant level (about 10 μkat/L until the end of the experiment. The same phenomenon was observed in the experimental groups, but the trend of declining GSH-Px activity in blood plasma was more expressed, and, contrary to the control group, was expressed also in the later phases of the experiment. In the 3rd week of the fattening period, GSH-Px plasma activity in broilers of the control and experimental groups was relatively equal, and then the plasma activity of GSH-Px in broilers of the experimental groups decreased, but there were no major differences among the individual groups.

Comparación de las velocidades alcanzadas entre dos test de campo de similares características: VAM-EVAL y UMTT

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G.C. García

2014-06-01

Conclusión: En estudiantes de educación física no se encontraron diferencias estadísticamente significativas en las VFA entre el UMTT y VAM-EVAL. De igual manera, no se encontraron diferencias en las distancias alcanzadas, la duración de los test y en el VO2máx estimado.

Study on the clinical significance of changes of serum SOD, LPO and GSH-PX levels in patients with leukemia after chemotherapy

International Nuclear Information System (INIS)

Li Xiumei; He Haoming; Teng Yuexin; Zhu Guihua; Han Xiuhua

2002-01-01

Objective: To explore the changes of serum SOD, LPO and GSH-PX levels after chemotherapy in patients with leukemia. Methods: Levels of serum SOD were determined by RIA, LPO, GSH-PX were determined by biochemical methods in 42 cases of leukemia both before and after chemotherapy and 30 normal controls. Results: The results showed that in patients with leukemia the SOD, GSH-PX levels were significantly lower than those in normal controls (p < 0.01) and LPO levels were higher than those in normal control (p<0.01) before, six months after chemotherapy, SOD, LPO, GSH-PX levels remained abnormal in the patients with recurrence but returned to normal in patients without relapse. Conclusion: Changes in these factors are closely related to prognosis of leukemia

Commissioning dosimetry for the laboratory irradiation facility type PX-γ-30

International Nuclear Information System (INIS)

Prieto Miranda, E.F.; Cuesta Fuente, G.I.; Chavez Ardanza, A.; Sainz Vidal, D.

1997-01-01

In the present paper at the laboratory irradiation type PX-y-30 was carried out the commissioning dosimetry, which belongs to Radiological Department of the CEADEN. It was determined the dose distribution as well as principal dosimetric parameters of the irradiation process. Besides, an irradiation position was found for the calibration or intercomparison of dosimetry systems

Relationship between glutation peroxidase (GSH-PX) activity and the uptake of 75-Se by erytrocytes for practical assesment of selenium status in dairy cows

International Nuclear Information System (INIS)

Danius, J.

1988-01-01

An experiment to study the relationship between glutation peroxidase (GSH-Px) activity and the uptake of 75-Se by erytrocytes was conducted for practical assesment of selenium status in Holstein-Friesian (HF) dairy cows. The blood used in the experiment was stored in refrigerator for 7 and 10 days. Radioselenium with a specific activity at about 0.84 mCi/m was used. A high negative correlatin (r = -0.86 and r = -0.98) was found between red blood cell GSH-Px activity and red blood cell uptake of 75-Se. Results indicated that red blood cell uptake of 75-Se can be used for determination of Se status in dairy cattle, although some factors which might affect red blood cell uptake of 75-Se should be calculated first. (author). 21 refs, 2 figs

Effect of protein-xanthophylls (PX) concentrate of alfalfa supplementation on physico-chemical properties of turkey breast and thigh muscles during ageing.

Science.gov (United States)

Karwowska, M; Stadnik, J; Dolatowski, Z J; Grela, E R

2010-10-01

The objective was to evaluate the effects of a dietary protein-xanthophylls (PX) concentrate of alfalfa to turkey diets (at 15 and 30 g kg(-1) feed) on the physico-chemical properties of breast and thigh muscles during ageing. The experiment involved 120 turkeys (Big-6 type) allotted to 3 groups (group I-control group; group II--with 1.5% supplementation of the protein-xanthophylls (PX) concentrate; group III--with 3% supplementation of the protein-xanthophylls (PX) concentrate). Measurements of pH, water holding capacity, color, oxymyoglobin content, TBARS and oxidation-reduction potential showed that the addition of protein-xanthophylls (PX) concentrate of alfalfa to a turkey diet did not cause deterioration of breast and thigh meat quality. In addition, changes in color, oxymyoglobin content, TBARS and oxidation-reduction potential values suggested that the inclusion of the concentrate to turkey diets acts as an antioxidant in the raw meat. Copyright (c) 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Neutron fragmentation in the reaction pn to pX at 19 GeV/c

CERN Document Server

Bakken, V; Lundborg, P; Makela, J; Pimiä, M; Selldén, B; Sundell, E; Tuominiemi, J

1979-01-01

Data on the reaction pn to pX are extracted from a pd experiment in the CERN 2 m DBC at 10 GeV/c. The cross-section for neutron fragmentation events with mod t mod <1 (GeV/c)/sup 2/ determined and compared with data at high energies at fixed M/sub x//sup 2//s and t. The cross-section can be described with the triple-Regge formula taking into account only the pion exchange contributions, i.e. the pi pi P and pi pi R terms. A leading-particle effect consistent with the pion exchange model is observed in the longitudinal-momentum distribution of the negative pions in the final state of the reaction pn to pX, when transformed to the rest frame of the recoiling system X. (10 refs).

Weak neutral current in the inclusive e+e- → p+X annihilation

International Nuclear Information System (INIS)

Grigoryan, S.G.; Esajbegyan, S.V.

1977-01-01

Polarization effects in the e + e - → p+X inclusive process are considered within the framework of the Weinberg model. Expressions for the asymmetry parameters and for the final particle polarization are obtained in the quark-parton approach. The quark gluon model by Farrar and Jackson is used for numerical estimates in the x approximately 1 region

Polarization of cumulative protons in the reaction. gamma. A r arrow pX

Energy Technology Data Exchange (ETDEWEB)

Avakyan, R.O.; Avetisyan, A.E.; Arestakesyan, G.A.; Bartikyan, M.V.; Garibyan, Y.A.; Grigoryan, A.E.; Eganov, V.S.; Karapetyan, A.P.; Karapetyan, M.P.; Keropyan, I.A.; and others

1989-02-01

The polarization of cumulative protons has been measured in the reaction {gamma}{ital A}{r arrow}{ital pX} in the proton-energy region 170--270 MeV for C and Sn nuclei in bremsstrahlung beams produced by 4.5- and 1.5-GeV electrons. The measured polarization value is close to zero.

Measurement of the polarization of cumulative protons in γA → pX reaction

International Nuclear Information System (INIS)

Avakyan, R.O.; Avakyan, E.O.; Avetisyan, A.Eh.

1985-01-01

The polarization of cumulative protons in γA → px reaction is measured in the range of proton energy (190+270) MeV for C, Cu, Sn, Pb nuclei. The measured polarization is practically independent of the energy of protons and the atomic number of nuclei

VAM2D: Variably saturated analysis model in two dimensions

International Nuclear Information System (INIS)

Huyakorn, P.S.; Kool, J.B.; Wu, Y.S.

1991-10-01

This report documents a two-dimensional finite element model, VAM2D, developed to simulate water flow and solute transport in variably saturated porous media. Both flow and transport simulation can be handled concurrently or sequentially. The formulation of the governing equations and the numerical procedures used in the code are presented. The flow equation is approximated using the Galerkin finite element method. Nonlinear soil moisture characteristics and atmospheric boundary conditions (e.g., infiltration, evaporation and seepage face), are treated using Picard and Newton-Raphson iterations. Hysteresis effects and anisotropy in the unsaturated hydraulic conductivity can be taken into account if needed. The contaminant transport simulation can account for advection, hydrodynamic dispersion, linear equilibrium sorption, and first-order degradation. Transport of a single component or a multi-component decay chain can be handled. The transport equation is approximated using an upstream weighted residual method. Several test problems are presented to verify the code and demonstrate its utility. These problems range from simple one-dimensional to complex two-dimensional and axisymmetric problems. This document has been produced as a user's manual. It contains detailed information on the code structure along with instructions for input data preparation and sample input and printed output for selected test problems. Also included are instructions for job set up and restarting procedures. 44 refs., 54 figs., 24 tabs

Search for exotic baryons in 800 GeV/c pp → pX

Science.gov (United States)

Christian, D. C.; Felix, J.; Gottschalk, E. E.; Gutierrez, G.; Hartouni, E. P.; Knapp, B. C.; Kreisler, M. N.; Moreno, G.; Reyes, M. A.; Sosa, M.; Wang, M. H. L. S.; Wehmann, A.

2006-05-01

We present preliminary results of the search for the pentaquark candidates Θ(1540) and Ξ(1862) using data from Fermilab experiment E690 in the reaction pp → pX at 800 GeV/c. We find that production of pentaquark resonances is heavily suppressed with respect to the production of normal baryon and antibaryon resonances.

DNA watermarks: A proof of concept

Directory of Open Access Journals (Sweden)

Barnekow Angelika

2008-04-01

Full Text Available Abstract Background DNA-based watermarks are helpful tools to identify the unauthorized use of genetically modified organisms (GMOs protected by patents. In silico analyses showed that in coding regions synonymous codons can be used to insert encrypted information into the genome of living organisms by using the DNA-Crypt algorithm. Results We integrated an authenticating watermark in the Vam7 sequence. For our investigations we used a mutant Saccharomyces cerevisiae strain, called CG783, which has an amber mutation within the Vam7 sequence. The CG783 cells are unable to sporulate and in addition display an abnormal vacuolar morphology. Transformation of CG783 with pRS314 Vam7 leads to a phenotype very similar to the wildtype yeast strain CG781. The integrated watermark did not influence the function of Vam7 and the resulting phenotype of the CG783 cells transformed with pRS314 Vam7-TB shows no significant differences compared to the CG783 cells transformed with pRS314 Vam7. Conclusion From our experiments we conclude that the DNA watermarks produced by DNA-Crypt do not influence the translation from mRNA into protein. By analyzing the vacuolar morphology, growth rate and ability to sporulate we confirmed that the resulting Vam7 protein was functionally active.

Analysis of manganese superoxide dismutase (MnSOD: Ala-9Val and glutathione peroxidase (GSH-Px: Pro 197 Leu gene polymorphisms in mood disorders.

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Birgül Elbozan Cumurcu

2013-05-01

Full Text Available We investigated the etiopathogenetic role of manganese superoxide dismutase (MnSOD (Ala-9Val and glutathione peroxidase (GSH-Px (Pro 197 Leu gene polymorphisms in patients diagnosed with major depressive disorder (MDD and bipolar I disorder (BD. Eighty patients with MDD, 82 patients with BD (total 162 patients and 96 healthy controls were enrolled in this study and genotyped using a Real Time-Quantitative Polymer Chain Reaction (RT-qPCR-based method. The patients with BD and MDD and the controls had a similar distribution of the genotypes and alleles in the Ala-9Val MnSOD gene polymorphism. Comparison of the MDD group and control group regarding the Pro197 Leu GSH-Px gene polymorphism revealed similar genotype distribution but different allele distribution. The BD group and control group were similar both for genotypes and for alleles when compared regarding the Pro 197 Leu GSH-Px gene polymorphism. The combined analysis (MDD plus BD also failed to find any association between the Ala-9Val MnSOD and Pro 197 Leu GSH-Px gene polymorphism. Although small statistical power of the current study the significant difference between patients with depression and the control group for the Pro 197 Leu GSH-Px polymorphism indicates that the distribution of these alleles may have a contribution in the physiopathogenesis of depression. One of the limitation of the current study is that the sample size is too small. Understanding of the exact role of Pro 197 LeuGSH-Px polymorphism in the development of depression needs to further studies with more sample size and high statistical power.

A three amino acid deletion in the transmembrane domain of the nicotinic acetylcholine receptor α6 subunit confers high-level resistance to spinosad in Plutella xylostella.

Science.gov (United States)

Wang, Jing; Wang, Xingliang; Lansdell, Stuart J; Zhang, Jianheng; Millar, Neil S; Wu, Yidong

2016-04-01

Spinosad is a macrocyclic lactone insecticide that acts primarily at the nicotinic acetylcholine receptors (nAChRs) of target insects. Here we describe evidence that high levels of resistance to spinosad in the diamondback moth (Plutella xylostella) are associated with a three amino acid (3-aa) deletion in the fourth transmembrane domain (TM4) of the nAChR α6 subunit (Pxα6). Following laboratory selection with spinosad, the SZ-SpinR strain of P. xylostella exhibited 940-fold resistance to spinosad. In addition, the selected insect population had 1060-fold cross-resistance to spinetoram but, in contrast, no cross-resistance to abamectin was observed. Genetic analysis indicates that spinosad resistance in SZ-SpinR is inherited as a recessive and autosomal trait, and that the 3-aa deletion (IIA) in TM4 of Pxα6 is tightly linked to spinosad resistance. Because of well-established difficulties in functional expression of cloned insect nAChRs, the analogous resistance-associated deletion mutation was introduced into a prototype nAChR (the cloned human α7 subunit). Two-electrode voltage-clamp recording with wild-type and mutated nAChRs expressed in Xenopus laevis oocytes indicated that the mutation causes a complete loss of agonist activation. In addition, radioligand binding studies indicated that the 3-aa deletion resulted in significantly lower-affinity binding of the extracellular neurotransmitter-binding site. These findings are consistent with the 3-amino acid (IIA) deletion within the transmembrane domain of Pxα6 being responsible for target-site resistance to spinosad in the SZ-SpinR strain of P. xylostella. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

SH3 domain-mediated binding of the Drk protein to Dos is an important step in signaling of Drosophila receptor tyrosine kinases.

Science.gov (United States)

Feller, Stephan M; Wecklein, Heike; Lewitzky, Marc; Kibler, Eike; Raabe, Thomas

2002-08-01

Activation of the Sevenless (Sev) receptor tyrosine kinase (RTK) in the developing Drosophila eye is required for the specification of the R7 photoreceptor cell fate. Daughter of Sevenless (Dos), a putative multi-site adaptor protein, is a substrate of the Sev kinase and is known to associate with the tyrosine phosphatase Corkscrew (Csw). Binding of Csw to Dos depends on the Csw Src homology 2 (SH2) domains and is an essential step for signaling by the Sev RTK. Dos, however, lacks a recognizable phosphotyrosine interaction domain and it was previously unclear how it is recruited to the Sev receptor. Here it is shown that the SH2/SH3 domain adaptor protein Drk can provide this link. Drk binds with its SH2 domain to the autophosphorylated Sev receptor while the C-terminal SH3 domain is able to associate with Dos. The Drk SH3 domain binding motifs on Dos were mapped to two sites which do not conform the known Drk SH3 domain binding motif (PxxPxR) but instead have the consensus PxxxRxxKP. Mutational analysis in vitro and in vivo provided evidence that both Drk binding sites fulfil an important function in the context of Sev and Drosophila epidermal growth factor receptor mediated signaling processes.

EFFECTS OF PROTEIN-XANTHOPHYLL (PX CONCENTRATE OF ALFALFA ADDITIVE TO CRUDE PROTEIN-REDUCED DIETS ON NITROGEN EXCRETION, GROWTH PERFORMANCE AND MEAT QUALITY OF PIGS

Directory of Open Access Journals (Sweden)

Eugeniusz GRELA

2009-06-01

Full Text Available The infl uence of protein-xanthophyll (PX concentrate of alfalfa supplement to crude protein-reduced diets was examined in relation to nitrogen excretion, performance parameters and pig meat quality. The investigations included 60 growers (PL x PLW x Duroc crossbreeds assigned to 3 groups. The conclusion is that there is a large potential to decrease nitrogen emission to the environment by 10% lowering of dietary crude protein intake along with reduced animal growth rate and elevated mixture utilization. Inclusion of a protein-xanthophyll concentrate (PX of alfalfa to the diet is likely to diminish disadvantageous productive parameters arising from limiting of total crude protein level in relation to the requirements of pigs feeding norms [1993]. At the same time, it improves feed nitrogen utilization and reduces noxious odour emissions from a piggery. The components of a protein-xanthophyll concentrate (PX contribute to increased liver and kidney weight.

Does video-assisted mediastinoscopy offer lower false-negative rates for subcarinal lymph nodes compared with standard cervical mediastinoscopy?

Science.gov (United States)

Citak, Necati; Buyukkale, Songul; Kok, Abdulaziz; Celikten, Alper; Metin, Muzaffer; Sayar, Adnan; Gurses, Atilla

2014-10-01

Theoretically, video-assisted mediastinoscopy (VAM) offers improved staging of subcarinal lymph nodes (LNs) compared with standard cervical mediastinoscopy (SCM). Materials and Between 2006 and 2011, 553 patients (SCM, n = 293; VAM, n = 260) with non-small cell lung carcinoma who underwent mediastinoscopy were investigated. Mediastinoscopy was performed only in select patients based on computed tomography (CT) or positron emission tomography CT scans in our center. The mean number of LNs and stations sampled per case was significantly higher with VAM (n = 7.65 ± 1.68 and n = 4.22 ± 0.83) than with SCM (n = 6.91 ± 1.65 and 3.92 ± 86.4; p < 0.001). The percentage of patients sampled in station 7 was significantly higher with VAM (98.8%) than with SCM (93.8%; p = 0.002). Mediastinal LN metastasis was observed in 114 patients by mediastinoscopy. The remaining 439 patients (203 patients in VAM and 236 in SCM) underwent thoracotomy and systematic mediastinal lymphadenectomy (SML). SML showed mediastinal nodal disease in 23 patients (false-negative [FN] rate, 5.2%). The FN rate was higher with SCM (n = 14, 5.9%) than with VAM (n = 9, 4.4%), although this difference was not statistically significant (p = 0.490). Station 7 was the most predominant station for FN results (n = 15). The FN rate of station 7 was found to be higher with SCM (n = 9, 3.8%) than with the VAM group (n = 6, 2.9%; p = 0.623). FN were more common in mediastinoscopy of subcarinal LNs. VAM allows higher rates of sampling of mediastinal LN stations and station 7, although it did not improve staging of subcarinal LNs. Georg Thieme Verlag KG Stuttgart · New York.

Enhancement of the catalytic activity of ferulic acid decarboxylase from Enterobacter sp. Px6-4 through random and site-directed mutagenesis.

Science.gov (United States)

Lee, Hyunji; Park, Jiyoung; Jung, Chaewon; Han, Dongfei; Seo, Jiyoung; Ahn, Joong-Hoon; Chong, Youhoon; Hur, Hor-Gil

2015-11-01

The enzyme ferulic acid decarboxylase (FADase) from Enterobacter sp. Px6-4 catalyzes the decarboxylation reaction of lignin monomers and phenolic compounds such as p-coumaric acid, caffeic acid, and ferulic acid into their corresponding 4-vinyl derivatives, that is, 4-vinylphenol, 4-vinylcatechol, and 4-vinylguaiacol, respectively. Among various ferulic acid decarboxylase enzymes, we chose the FADase from Enterobacter sp. Px6-4, whose crystal structure is known, and produced mutants to enhance its catalytic activity by random and site-directed mutagenesis. After three rounds of sequential mutations, FADase(F95L/D112N/V151I) showed approximately 34-fold higher catalytic activity than wild-type for the production of 4-vinylguaiacol from ferulic acid. Docking analyses suggested that the increased activity of FADase(F95L/D112N/V151I) could be due to formation of compact active site compared with that of the wild-type FADase. Considering the amount of phenolic compounds such as lignin monomers in the biomass components, successfully bioengineered FADase(F95L/D112N/V151I) from Enterobacter sp. Px6-4 could provide an ecofriendly biocatalytic tool for producing diverse styrene derivatives from biomass.

Phosphatidylinositol 3,5-Bisphosphate-Rich Membrane Domains in Endosomes and Lysosomes.

Science.gov (United States)

Takatori, Sho; Tatematsu, Tsuyako; Cheng, Jinglei; Matsumoto, Jun; Akano, Takuya; Fujimoto, Toyoshi

2016-02-01

Phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2 ) has critical functions in endosomes and lysosomes. We developed a method to define nanoscale distribution of PtdIns(3,5)P2 using freeze-fracture electron microscopy. GST-ATG18-4×FLAG was used to label PtdIns(3,5)P2 and its binding to phosphatidylinositol 3-phosphate (PtdIns(3)P) was blocked by an excess of the p40(phox) PX domain. In yeast exposed to hyperosmotic stress, PtdIns(3,5)P2 was concentrated in intramembrane particle (IMP)-deficient domains in the vacuolar membrane, which made close contact with adjacent membranes. The IMP-deficient domain was also enriched with PtdIns(3)P, but was deficient in Vph1p, a liquid-disordered domain marker. In yeast lacking either PtdIns(3,5)P2 or its effector, Atg18p, the IMP-deficient, PtdIns(3)P-rich membranes were folded tightly to make abnormal tubular structures, thus showing where the vacuolar fragmentation process is arrested when PtdIns(3,5)P2 metabolism is defective. In HeLa cells, PtdIns(3,5)P2 was significantly enriched in the vesicular domain of RAB5- and RAB7-positive endosome/lysosomes of the tubulo-vesicular morphology. This biased distribution of PtdIns(3,5)P2 was also observed using fluorescence microscopy, which further showed enrichment of a retromer component, VPS35, in the tubular domain. This is the first report to show segregation of PtdIns(3,5)P2 -rich and -deficient domains in endosome/lysosomes, which should be important for endosome/lysosome functionality. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Toxoplasma gondii GRA7-Targeted ASC and PLD1 Promote Antibacterial Host Defense via PKCα.

Science.gov (United States)

Koh, Hyun-Jung; Kim, Ye-Ram; Kim, Jae-Sung; Yun, Jin-Seung; Jang, Kiseok; Yang, Chul-Su

2017-01-01

Tuberculosis is a global health problem and at least one-third of the world's population is infected with Mycobacterium tuberculosis (MTB). MTB is a successful pathogen that enhances its own intracellular survival by inhibiting inflammation and arresting phago-lysosomal fusion. We previously demonstrated that Toxoplasma gondii (T. gondii) dense granule antigen (GRA) 7 interacts with TNF receptor-associated factor 6 via Myeloid differentiation primary response gene 88, enabling innate immune responses in macrophages. To extend these studies, we found that GRA7 interacts with host proteins involved in antimicrobial host defense mechanisms as a therapeutic strategy for tuberculosis. Here, we show that protein kinase C (PKC)α-mediated phosphorylation of T. gondii GRA7-I (Ser52) regulates the interaction of GRA7 with PYD domain of apoptosis-associated speck-like protein containing a carboxy-terminal CARD, which is capable of oligomerization and inflammasome activation can lead to antimicrobial defense against MTB. Furthermore, GRA7-III interacted with the PX domain of phospholipase D1, facilitating its enzyme activity, phago-lysosomal maturation, and subsequent antimicrobial activity in a GRA7-III (Ser135) phosphorylation-dependent manner via PKCα. Taken together, these results underscore a previously unrecognized role of GRA7 in modulating antimicrobial host defense mechanism during mycobacterial infection.

Toxoplasma gondii GRA7-Targeted ASC and PLD1 Promote Antibacterial Host Defense via PKCα.

Directory of Open Access Journals (Sweden)

Hyun-Jung Koh

2017-01-01

Full Text Available Tuberculosis is a global health problem and at least one-third of the world's population is infected with Mycobacterium tuberculosis (MTB. MTB is a successful pathogen that enhances its own intracellular survival by inhibiting inflammation and arresting phago-lysosomal fusion. We previously demonstrated that Toxoplasma gondii (T. gondii dense granule antigen (GRA 7 interacts with TNF receptor-associated factor 6 via Myeloid differentiation primary response gene 88, enabling innate immune responses in macrophages. To extend these studies, we found that GRA7 interacts with host proteins involved in antimicrobial host defense mechanisms as a therapeutic strategy for tuberculosis. Here, we show that protein kinase C (PKCα-mediated phosphorylation of T. gondii GRA7-I (Ser52 regulates the interaction of GRA7 with PYD domain of apoptosis-associated speck-like protein containing a carboxy-terminal CARD, which is capable of oligomerization and inflammasome activation can lead to antimicrobial defense against MTB. Furthermore, GRA7-III interacted with the PX domain of phospholipase D1, facilitating its enzyme activity, phago-lysosomal maturation, and subsequent antimicrobial activity in a GRA7-III (Ser135 phosphorylation-dependent manner via PKCα. Taken together, these results underscore a previously unrecognized role of GRA7 in modulating antimicrobial host defense mechanism during mycobacterial infection.

Study of the (p,px) reaction at 156 MeV on some light nuclei; Etude de la reaction (p,px) a 156 Mev sur quelques noyaux legers

Energy Technology Data Exchange (ETDEWEB)

Bachelier, Daniel

1971-05-04

This research thesis reports the study of four quasi-elastic diffusion reactions of (p,px) type at 156 MeV: {sup 6}Li(p,pd ){sup 4}He, {sup 6}Li(p,pr){sup 3}H, {sup 7}Li(p,pt){sup 4}He and {sup 12}C(p,pd){sup 10}B. The objectives were to check the quasi-elastic character of these reactions and to describe them by pulse approximations with plane waves, to study their selection rules and to understand their angular correlations with respect to momentum distribution in the target nucleus of ejected substructures (clusters), to compare the probabilities of different configurations corresponding to different models, and, in the case of carbon, to compare the experimental energy spectrum with theoretical predictions. After a discussion of the theoretical expression of the cross-section of a quasi-elastic reaction, and a presentation of the different nuclear models which have been used for this reaction type, the author reports the study of the kinematics of these reactions by defining the conditions under which the knock-out mechanism is promoted. The author describes the beam, targets, detectors and electronic devices used for this study. He addresses the methods used to identify events and to analyse results. Experimental results are presented and compared with theoretical results and with other published experimental results.

Insight into the Selectivity of the G7-18NATE Inhibitor Peptide for the Grb7-SH2 Domain Target.

Science.gov (United States)

Watson, Gabrielle M; Lucas, William A H; Gunzburg, Menachem J; Wilce, Jacqueline A

2017-01-01

Growth factor receptor bound protein 7 (Grb7) is an adaptor protein with established roles in the progression of both breast and pancreatic cancers. Through its C-terminal SH2 domain, Grb7 binds to phosphorylated tyrosine kinases to promote proliferative and migratory signaling. Here, we investigated the molecular basis for the specificity of a Grb7 SH2-domain targeted peptide inhibitor. We identified that arginine 462 in the BC loop is unique to Grb7 compared to Grb2, another SH2 domain bearing protein that shares the same consensus binding motif as Grb7. Using surface plasmon resonance we demonstrated that Grb7-SH2 binding to G7-18NATE is reduced 3.3-fold when the arginine is mutated to the corresponding Grb2 amino acid. The reverse mutation in Grb2-SH2 (serine to arginine), however, was insufficient to restore binding of G7-18NATE to Grb2-SH2. Further, using a microarray, we confirmed that G7-18NATE is specific for Grb7 over a panel of 79 SH2 domains, and identified that leucine at the βD6 position may also be a requirement for Grb7-SH2 binding. This study provides insight into the specificity defining features of Grb7 for the inhibitor molecule G7-18NATE, that will assist in the development of improved Grb7 targeted inhibitors.

Insight into the Selectivity of the G7-18NATE Inhibitor Peptide for the Grb7-SH2 Domain Target

Directory of Open Access Journals (Sweden)

Gabrielle M. Watson

2017-09-01

Full Text Available Growth factor receptor bound protein 7 (Grb7 is an adaptor protein with established roles in the progression of both breast and pancreatic cancers. Through its C-terminal SH2 domain, Grb7 binds to phosphorylated tyrosine kinases to promote proliferative and migratory signaling. Here, we investigated the molecular basis for the specificity of a Grb7 SH2-domain targeted peptide inhibitor. We identified that arginine 462 in the BC loop is unique to Grb7 compared to Grb2, another SH2 domain bearing protein that shares the same consensus binding motif as Grb7. Using surface plasmon resonance we demonstrated that Grb7-SH2 binding to G7-18NATE is reduced 3.3-fold when the arginine is mutated to the corresponding Grb2 amino acid. The reverse mutation in Grb2-SH2 (serine to arginine, however, was insufficient to restore binding of G7-18NATE to Grb2-SH2. Further, using a microarray, we confirmed that G7-18NATE is specific for Grb7 over a panel of 79 SH2 domains, and identified that leucine at the βD6 position may also be a requirement for Grb7-SH2 binding. This study provides insight into the specificity defining features of Grb7 for the inhibitor molecule G7-18NATE, that will assist in the development of improved Grb7 targeted inhibitors.

Insight into the Selectivity of the G7-18NATE Inhibitor Peptide for the Grb7-SH2 Domain Target

Science.gov (United States)

Watson, Gabrielle M.; Lucas, William A. H.; Gunzburg, Menachem J.; Wilce, Jacqueline A.

2017-01-01

Growth factor receptor bound protein 7 (Grb7) is an adaptor protein with established roles in the progression of both breast and pancreatic cancers. Through its C-terminal SH2 domain, Grb7 binds to phosphorylated tyrosine kinases to promote proliferative and migratory signaling. Here, we investigated the molecular basis for the specificity of a Grb7 SH2-domain targeted peptide inhibitor. We identified that arginine 462 in the BC loop is unique to Grb7 compared to Grb2, another SH2 domain bearing protein that shares the same consensus binding motif as Grb7. Using surface plasmon resonance we demonstrated that Grb7-SH2 binding to G7-18NATE is reduced 3.3-fold when the arginine is mutated to the corresponding Grb2 amino acid. The reverse mutation in Grb2-SH2 (serine to arginine), however, was insufficient to restore binding of G7-18NATE to Grb2-SH2. Further, using a microarray, we confirmed that G7-18NATE is specific for Grb7 over a panel of 79 SH2 domains, and identified that leucine at the βD6 position may also be a requirement for Grb7-SH2 binding. This study provides insight into the specificity defining features of Grb7 for the inhibitor molecule G7-18NATE, that will assist in the development of improved Grb7 targeted inhibitors. PMID:29018805

Effects of bradyrhiziobium and vesicular arbuscular mycorrhizal (VAM) inoculation on symbiotic properties, yield and seed quality of groundnut

Energy Technology Data Exchange (ETDEWEB)

Mohamedzein, Ekhlas Mohamedzein M [Department of Biochemistry and Soil Science, Faculty of agriculture, University of Khartoum, Khartoum (Sudan)

1996-11-01

A local and introduced Bradyrhizobium strains and a locally-isolated VAM fungi were used to study their effects on groundnut in clay (Shambat) and sandy (El-Rwakeeb) soil in a pot experiment. A field experiment was carried out at El-Rwakeeb to study the effect of urea, superphosphate and chicken manure on inoculated or uninoculated groundnut. Inoculation significantly increased number of nodules, dry weight of shoot, root and nodules, plant N and P content, number and dry weight of pods, yield and seed composition and quality in both pot and field experiments. Introduced strain (TAL 1000) was more effective than locally- isolated strain (ENRRI 16). All fertilizers added to inoculated or uninoculated groundnut significantly increased all measured parameters. Chiken manure reflected good results than rea and superphosphate, which showed comparable results. All treatents significantly improved the seed composition especially protein and oil content. (Author) 89 refs. , 25 tabs.

Effects of bradyrhiziobium and vesicular arbuscular mycorrhizal (VAM) inoculation on symbiotic properties, yield and seed quality of groundnut

International Nuclear Information System (INIS)

Mohamedzein, Ekhlas Mohamedzein M.

1996-11-01

A local and introduced Bradyrhizobium strains and a locally-isolated VAM fungi were used to study their effects on groundnut in clay (Shambat) and sandy (El-Rwakeeb) soil in a pot experiment. A field experiment was carried out at El-Rwakeeb to study the effect of urea, superphosphate and chicken manure on inoculated or uninoculated groundnut. Inoculation significantly increased number of nodules, dry weight of shoot, root and nodules, plant N and P content, number and dry weight of pods, yield and seed composition and quality in both pot and field experiments. Introduced strain (TAL 1000) was more effective than locally- isolated strain (ENRRI 16). All fertilizers added to inoculated or uninoculated groundnut significantly increased all measured parameters. Chiken manure reflected good results than rea and superphosphate, which showed comparable results. All treatents significantly improved the seed composition especially protein and oil content. (Author)

Gene transfer and expression in human neutrophils. The phox homology domain of p47phox translocates to the plasma membrane but not to the membrane of mature phagosomes

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Brzezinska Agnieszka A

2006-12-01

Full Text Available Abstract Background Neutrophils are non-dividing cells with poor survival after isolation. Consequently, exogenous gene expression in neutrophils is challenging. We report here the transfection of genes and expression of active proteins in human primary peripheral neutrophils using nucleofection. Results Exogenous gene expression in human neutrophils was achieved 2 h post-transfection. We show that neutrophils transfected by nucleofection are functional cells, able to respond to soluble and particulate stimuli. They conserved the ability to undergo physiological processes including phagocytosis. Using this technique, we were able to show that the phox homology (PX domain of p47phox localizes to the plasma membrane in human neutrophils. We also show that RhoB, but not the PX domain of p47phox, is translocated to the membrane of mature phagosomes. Conclusion We demonstrated that cDNA transfer and expression of exogenous protein in human neutrophils is compatible with cell viability and is no longer a limitation for the study of protein function in human neutrophils.

Crystal structure of the Xpo1p nuclear export complex bound to the SxFG/PxFG repeats of the nucleoporin Nup42p.

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Koyama, Masako; Hirano, Hidemi; Shirai, Natsuki; Matsuura, Yoshiyuki

2017-10-01

Xpo1p (yeast CRM1) is the major nuclear export receptor that carries a plethora of proteins and ribonucleoproteins from the nucleus to cytoplasm. The passage of the Xpo1p nuclear export complex through nuclear pore complexes (NPCs) is facilitated by interactions with nucleoporins (Nups) containing extensive repeats of phenylalanine-glycine (so-called FG repeats), although the precise role of each Nup in the nuclear export reaction remains incompletely understood. Here we report structural and biochemical characterization of the interactions between the Xpo1p nuclear export complex and the FG repeats of Nup42p, a nucleoporin localized at the cytoplasmic face of yeast NPCs and has characteristic SxFG/PxFG sequence repeat motif. The crystal structure of Xpo1p-PKI-Nup42p-Gsp1p-GTP complex identified three binding sites for the SxFG/PxFG repeats on HEAT repeats 14-20 of Xpo1p. Mutational analyses of Nup42p showed that the conserved serines and prolines in the SxFG/PxFG repeats contribute to Xpo1p-Nup42p binding. Our structural and biochemical data suggest that SxFG/PxFG-Nups such as Nup42p and Nup159p at the cytoplasmic face of NPCs provide high-affinity docking sites for the Xpo1p nuclear export complex in the terminal stage of NPC passage and that subsequent disassembly of the nuclear export complex facilitates recycling of free Xpo1p back to the nucleus. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

Measurement and calculation of cross section for (p,x) reactions on natural Fe for 650 MeV protons

International Nuclear Information System (INIS)

Janczyszyn, J.; Pohorecki, W.; Domanska, G.; Loska, L.; Taczanowski, S.; Shvetsov, V.

2006-01-01

Cross sections for production of radionuclides in (p,x) reactions on natural iron were measured for protons of 650 ± 4 MeV with the use of HPGe gamma spectrometry and calculated with the MCNPX code. The determined cross section values were compared with the computed and other experimental ones

On the Oral-Formulaic Theory and its Application in the Poetic Edda: The Cases of Alvíssmál and Hávamál

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Diego Ferioli

2010-03-01

Full Text Available The aim of this essay is to make some considerations concerning the usage and the development of the Oral-Formulaic Theory since its initial stage in the field of Eddic studies. Doing so I will comment on the most relevant problems and scholarly views I encountered while I was dealing with the subject, and in some cases give my own interpretation of them. In the second part of the paper I will then discuss more in detail the Eddic poems Alvíssmál and Hávamál from an oral-formulaic point of view.

Intravenous and Subcutaneous Toxicity and Absorption Kinetics in Mice and Dogs of the Antileishmanial Triterpene Saponin PX-6518

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Louis Maes

2013-04-01

Full Text Available The intravenous (IV and subcutaneous (SC toxicity and absorption kinetics of the antileishmanial triterpene saponin PX-6518 and its active constituents maesabalide-III and -IV were studied in mice and dogs. A high-dose wash-out study of PX-6518 at 20 mg/kg SC for 5 days and a single low-dose wash-out study at 1, 2.5 or 5 mg/kg SC and IV with follow-up until day 35 after treatment were performed in mice. Beagle dogs received three escalating doses of maesabalide-III and -IV at weekly intervals (0.01, 0.1 and 0.5 mg/kg IV and maesabalide-III was also dosed SC at 0.1, 0.2 and 0.4 mg/kg. Endpoint measurements included clinical, hematological and serum biochemical parameters. Pathology and toxicokinetic studies were performed on the dogs. Whereas the neutrophils and aspartate aminotransferase and alanine aminotransferase levels were increased in the high-dose wash-out mouse study, these parameters did not change in the low-dose wash-out study. The dogs were far more susceptible than mice to liver toxicity (hepatocellular necrosis and elevated liver enzymes and developed a painful inflammatory reaction at the SC injection site. Toxicokinetic analysis revealed a non dose-linear systemic availability with plasma concentrations above the antileishmanial IC50 after only a single dose at 0.01 mg/kg IV or 0.1 mg/kg SC. Related to the long half-life (T1/2 71–91 h after SC dosing, repeated dosing at weekly intervals may result in drug accumulation and enhanced toxicity. It was decided not to pursue further drug development for PX-6518 because of the hepatotoxic risk.

A photosynthesis-based two-leaf canopy stomatal conductance model for meteorology and air quality modeling with WRF/CMAQ PX LSM

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A coupled photosynthesis-stomatal conductance model with single-layer sunlit and shaded leaf canopy scaling is implemented and evaluated in a diagnostic box model with the Pleim-Xiu land surface model (PX LSM) and ozone deposition model components taken directly from the meteorol...

Shear at Twin Domain Boundaries in YBa2Cu3O7-x

Science.gov (United States)

Caldwell, W. A.; Tamura, N.; Celestre, R. S.; MacDowell, A. A.; Padmore, H. A.; Geballe, T. H.; Koster, G.; Batterman, B. W.; Patel, J. R.

2004-05-01

The microstructure and strain state of twin domains in YBa2Cu3O7-x are discussed based upon synchrotron white-beam x-ray microdiffraction measurements. Intensity variations of the fourfold twin splitting of Laue diffraction peaks are used to determine the twin domain structure. Strain analysis shows that interfaces between neighboring twin domains are strained in shear, whereas the interior of these domains are regions of low strain. These measurements are consistent with the orientation relationships of twin boundaries within and across domains and show that basal plane shear stresses can exceed 100MPa where twin domains meet. Our results support stress field pinning of magnetic flux vortices by twin domain boundaries.

Cystoviral polymerase complex protein P7 uses its acidic C-terminal tail to regulate the RNA-directed RNA polymerase P2.

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Alphonse, Sébastien; Arnold, Jamie J; Bhattacharya, Shibani; Wang, Hsin; Kloss, Brian; Cameron, Craig E; Ghose, Ranajeet

2014-07-15

In bacteriophages of the cystovirus family, the polymerase complex (PX) encodes a 75-kDa RNA-directed RNA polymerase (P2) that transcribes the double-stranded RNA genome. Also a constituent of the PX is the essential protein P7 that, in addition to accelerating PX assembly and facilitating genome packaging, plays a regulatory role in transcription. Deletion of P7 from the PX leads to aberrant plus-strand synthesis suggesting its influence on the transcriptase activity of P2. Here, using solution NMR techniques and the P2 and P7 proteins from cystovirus ϕ12, we demonstrate their largely electrostatic interaction in vitro. Chemical shift perturbations on P7 in the presence of P2 suggest that this interaction involves the dynamic C-terminal tail of P7, more specifically an acidic cluster therein. Patterns of chemical shift changes induced on P2 by the P7 C-terminus resemble those seen in the presence of single-stranded RNA suggesting similarities in binding. This association between P2 and P7 reduces the affinity of the former toward template RNA and results in its decreased activity both in de novo RNA synthesis and in extending a short primer. Given the presence of C-terminal acidic tracts on all cystoviral P7 proteins, the electrostatic nature of the P2/P7 interaction is likely conserved within the family and could constitute a mechanism through which P7 regulates transcription in cystoviruses. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Knocking-out extra domain A alternative splice fragment of fibronectin using a clustered regularly interspaced short palindromic repeats/associated proteins 9 system].

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Yang, Yue; Wang, Haicheng; Xu, Shuyu; Peng, Jing; Jiang, Jiuhui; Li, Cuiying

2015-08-01

To investigate the effect of the fibronectin extra domain A on the aggressiveness of salivary adenoid cystic carcinoma (SACC) cells, via the clustered regularly interspaced short palindromic repeats (CRISPR)/ associated proteins (Cas) system. One sgRNA was designed to target the upstream of the genome sequences of extra domain A(EDA) exon and the downstream. Then the sgRNA was linked into plasmid PX-330 and transfected into SACC-83 cells. PCR and DNA sequence were used to testify the knockout cells, and the monoclones of EDA absent SACC cells were selected (A+C-2, A+C-6, B+C-10). CCK-8 cell proliferation and invasion was then tested in control group and the experimental group. The sgRNA was successfully linked into PX-330 plasmid. Part of adenoid cystic carcinoma cells' SACC-83 genomic EDA exon was knocked out, and the knockdown efficiency was above 70%, but the total amount of fibronectin did not change significantly. Three monoclones of EDA absent SACC- 83 cells were successfully selected with diminished migration and proliferation. The CRISPR/Cas9 system was a simplified system with relatively high knockout efficiency and EDA knockout could inhibiting SACC cell's mobility and invasiveness.

Effects of Velvet Antler with Blood on Bone in Ovariectomized Rats

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Ching-Chiung Wang

2012-09-01

Full Text Available In traditional Chinese medicine (TCM, both velvet antlers (VA and VA blood can tonify qi, essence, and marrow, nourish the blood, and invigorate bones and tendons. In TCM, the combination of VA and VA blood is believed to have superior pharmacological effects. Scientific evidence supporting the traditional therapeutic preference for redder antler is needed. The effectiveness of the combination therapy of VA middle sections (VAMs and VA blood (VAM-B was first examined in promoting proliferation of mouse osteoblastic cells (MC3T3-E1. The anti-osteoporotic activity of VAM-B (ratio of VAM:VA blood = 1:0.2 was evaluated with ovariectomized (OVX rats at a dose of 0.2 g/kg. In VAM-B-treated OVX rats, the body weight decreased 10.7%, and the strength of vertebrae and the femur respectively increased 18.1% and 15.4%, compared to the control. VAM-B treatment also recovered the estrogen-related loss of the right tibial trabecular bone microarchitecture. Alkaline phosphatase (ALP significantly decreased, but estradiol did not significantly change in serum of VAM-B-treated OVX rats. We also provide an effective strategy to enhance the anti-osteoporotic activity of VAM. In conclusion, our results provide scientific evidence supporting the traditional therapeutic preference of redder antler and indicate that VAM-B is a potential therapeutic agent for managing osteoporosis.

Cloning and analysis of peptidoglycan recognition protein-LC and immune deficiency from the diamondback moth, Plutella xylostella.

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Zhan, Ming-Yue; Yang, Pei-Jin; Rao, Xiang-Jun

2018-02-01

Peptidoglycan (PGN) exists in both Gram-negative and Gram-positive bacteria as a component of the cell wall. PGN is an important target to be recognized by the innate immune system of animals. PGN recognition proteins (PGRP) are responsible for recognizing PGNs. In Drosophila melanogaster, PGRP-LC and IMD (immune deficiency) are critical for activating the Imd pathway. Here, we report the cloning and analysis of PGRP-LC and IMD (PxPGRP-LC and PxIMD) from diamondback moth, Plutella xylostella (L.), the insect pest of cruciferous vegetables. PxPGRP-LC gene consists of six exons encoding a polypeptide of 308 amino acid residues with a transmembrane region and a PGRP domain. PxIMD cDNA encodes a polypeptide of 251 amino acid residues with a death domain. Sequence comparisons indicate that they are characteristic of Drosophila PGRP-LC and IMD homologs. PxPGRP-LC and PxIMD were expressed in various tissues and developmental stages. Their mRNA levels were affected by bacterial challenges. The PGRP domain of PxPGRP-LC lacks key residues for the amidase activity, but it can recognize two types of PGNs. Overexpression of full-length and deletion mutants in Drosophila S2 cells induced expression of some antimicrobial peptide genes. These results indicate that PxPGRP-LC and PxIMD may be involved in the immune signaling of P. xylostella. This study provides a foundation for further studies of the immune system of P. xylostella. © 2017 Wiley Periodicals, Inc.

Crystal structures of the UBX domain of human UBXD7 and its complex with p97 ATPase.

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Li, Zhi-Hui; Wang, Yong; Xu, Min; Jiang, Tao

2017-04-22

In humans, UBXD7 (also called UBXN7), an adaptor of p97 ATPase, can participate in the degradation of misfolded or damaged proteins in the p97-mediated ubiquitin proteasome system (UPS). UBXD7 binds to ubiquitinated substrates via its UBA domain and interacts with p97 N-terminal domain through its UBX domain to recruit p97 or the p97 core complex (p97/NPL4/UFD1). Here, we report the crystal structures of the UBX domain of UBXD7 (UBXD7 UBX ) at 2.0 Å resolution and its complex with p97 N-terminal domain (p97 NTD -UBXD7 UBX complex) at 2.4 Å resolution. A structural analysis and isothermal titration calorimetry results provide detailed molecular basis of interaction between UBXD7 UBX and p97 NTD . Moreover, structural superpositions suggest that dimerization of UBXD7 UBX via an intermolecular disulfide bond could interfere with the formation of the p97 NTD -UBXD7 UBX complex. Interestingly, UBXD7 may have a cooperative effect on p97 interaction with UFD1. Together, these results provide structural and biochemical insights into the interaction between p97 NTD and UBXD7 UBX . Copyright © 2017 Elsevier Inc. All rights reserved.

Molecular Characterization and the Function of Argonaute3 in RNAi Pathway of Plutella xylostella.

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Hameed, Muhammad Salman; Wang, Zhengbing; Vasseur, Liette; Yang, Guang

2018-04-20

Argonaute (Ago) protein family plays a key role in the RNA interference (RNAi) process in different insects including Lepidopteran. However, the role of Ago proteins in the RNAi pathway of Plutella xylostella is still unknown. We cloned an Argonaute3 gene in P. xylostella ( PxAgo3 ) with the complete coding sequence of 2832 bp. The encoded protein had 935 amino acids with an expected molecular weight of 108.9 kDa and an isoelectric point of 9.29. It contained a PAZ (PIWI/Argonaute/Zwile) domain and PIWI (P-element-induced whimpy testes) domain. PxAgo3 was classified into the Piwi subfamily of Ago proteins with a high similarity of 93.0% with Bombyx mori Ago3 (BmAgo3). The suppression of PxAgo3 by dsPxAgo3 was observed 3 h after treatment and was maintained until 24 h. Knockdown of PxAgo3 decreased the suppression level of PxActin by dsPxActin in P. xylostella cells, while overexpression of PxAgo3 increased the RNAi efficiency. Our results suggest that PxAgo3 play a key role in the double stranded RNA (dsRNA)-regulated RNAi pathway in P. xylostella .

ADAM disintegrin-like domain recognition by the lymphocyte integrins α4β1 and α4β7

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Bridges, Lance C.; Sheppard, Dean; Bowditch, Ron D.

2004-01-01

The ADAM (a disintegrin and metalloprotease) family of proteins possess both proteolytic and adhesive domains. We have established previously that the disintegrin domain of ADAM28, an ADAM expressed by human lymphocytes, is recognized by the integrin α4β1. The present study characterizes the integrin binding properties of the disintegrin-like domains of human ADAM7, ADAM28 and ADAM33 with the integrins α4β1, α4β7 and α9β1. Cell-adhesion assays demonstrated that, similar to ADAM28, the ADAM7 disintegrin domain supported α4β1-dependent Jurkat cell adhesion, whereas the ADAM33 disintegrin domain did not. The lymphocyte integrin α4β7 was also found to recognize both disintegrin domains of ADAM7 and ADAM28, but not of ADAM33. This is the first demonstration that mammalian disintegrins are capable of interacting with α4β7. All three disintegrin domains supported α9β1-dependent cell adhesion. Recognition by both α4β1 and α4β7 of ADAM7 and ADAM28 was activation-dependent, requiring either the presence of Mn2+ or an activating monoclonal antibody for cell attachment. Charge-to-alanine mutagenesis experiments revealed that the same residues within an individual ADAM disintegrin domain function in recognizing multiple integrins. However, the residues within a specific region of each ADAM disintegrin-like domain required for integrin binding were distinct. These results establish that ADAM7 and ADAM28 are recognized by the leucocyte integrins α4β1, α4β7 and α9β1. ADAM33 exclusively supported only α9β1-dependent adhesion. PMID:15504110

C-terminal region of MAP7 domain containing protein 3 (MAP7D3 promotes microtubule polymerization by binding at the C-terminal tail of tubulin.

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Saroj Yadav

Full Text Available MAP7 domain containing protein 3 (MAP7D3, a newly identified microtubule associated protein, has been shown to promote microtubule assembly and stability. Its microtubule binding region has been reported to consist of two coiled coil motifs located at the N-terminus. It possesses a MAP7 domain near the C-terminus and belongs to the microtubule associated protein 7 (MAP7 family. The MAP7 domain of MAP7 protein has been shown to bind to kinesin-1; however, the role of MAP7 domain in MAP7D3 remains unknown. Based on the bioinformatics analysis of MAP7D3, we hypothesized that the MAP7 domain of MAP7D3 may have microtubule binding activity. Indeed, we found that MAP7 domain of MAP7D3 bound to microtubules as well as enhanced the assembly of microtubules in vitro. Interestingly, a longer fragment MDCT that contained the MAP7 domain (MD with the C-terminal tail (CT of the protein promoted microtubule polymerization to a greater extent than MD and CT individually. MDCT stabilized microtubules against dilution induced disassembly. MDCT bound to reconstituted microtubules with an apparent dissociation constant of 3.0 ± 0.5 µM. An immunostaining experiment showed that MDCT localized along the length of the preassembled microtubules. Competition experiments with tau indicated that MDCT shares its binding site on microtubules with tau. Further, we present evidence indicating that MDCT binds to the C-terminal tail of tubulin. In addition, MDCT could bind to tubulin in HeLa cell extract. Here, we report a microtubule binding region in the C-terminal region of MAP7D3 that may have a role in regulating microtubule assembly dynamics.

First principles examination of electronic structure and optical features of 4H-GaN1-xPx polytype alloys

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Laref, A.; Hussain, Z.; Laref, S.; Yang, J. T.; Xiong, Y. C.; Luo, S. J.

2018-04-01

By using first-principles calculations, we compute the electronic band structures and typical aspects of the optical spectra of hexagonally structured GaN1-xPx alloys. Although a type III-V semiconductor, GaP commonly possesses a zinc-blende structure with an indirect band gap; as such, it may additionally form hexagonal polytypes under specific growth conditions. The electronic structures and optical properties are calculated by combining a non-nitride III-V semiconductor and a nitride III-V semiconductor, as GaP and GaN crystallizing in a 4H polytype, with the N composition ranging between x = 0-1. For all studied materials, the energy gap is found to be direct. The optical properties of the hexagonal materials may illustrate the strong polarization dependence owing to the crystalline anisotropy. This investigation for GaN1-xPx alloys is anticipated to supply paramount information for applications in the visible/ultraviolet spectral regions. At a specific concentration, x, these alloys would be exclusively appealing candidates for solar-cell applications.

Study of the (p,px) reaction at 156 MeV on some light nuclei

International Nuclear Information System (INIS)

Bachelier, Daniel

1971-01-01

This research thesis reports the study of four quasi-elastic diffusion reactions of (p,px) type at 156 MeV: 6 Li(p,pd ) 4 He, 6 Li(p,pr) 3 H, 7 Li(p,pt) 4 He and 12 C(p,pd) 10 B. The objectives were to check the quasi-elastic character of these reactions and to describe them by pulse approximations with plane waves, to study their selection rules and to understand their angular correlations with respect to momentum distribution in the target nucleus of ejected substructures (clusters), to compare the probabilities of different configurations corresponding to different models, and, in the case of carbon, to compare the experimental energy spectrum with theoretical predictions. After a discussion of the theoretical expression of the cross-section of a quasi-elastic reaction, and a presentation of the different nuclear models which have been used for this reaction type, the author reports the study of the kinematics of these reactions by defining the conditions under which the knock-out mechanism is promoted. The author describes the beam, targets, detectors and electronic devices used for this study. He addresses the methods used to identify events and to analyse results. Experimental results are presented and compared with theoretical results and with other published experimental results

Simulation of the field dose of the irradiator PX γ 30 using MCNP

International Nuclear Information System (INIS)

Torres, N.; Prieto, E. F.; Chavez, A.; Rosales, J.

2011-01-01

Given the acceptance and actual application of radiation technology for research purposes, industrial and trade is increasing, and that safety and quality of the product being treated by radiation technology is a function of absorbed dose, it becomes necessary to have a good characterization of the radiation field at processing volume, avoiding in this way that the product receives a different dose that affects its properties, or failure to reach the desired effect, which in many cases would be embarrassing. The simulation using the MCNP program, which uses probabilistic Monte Carlo code, can correctly characterize the dose field in the irradiation chamber of research irradiator PX γ 30 used in the CEADEN. (Author)

Multiscale Simulations Suggest a Mechanism for the Association of the Dok7 PH Domain with PIP-Containing Membranes.

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Amanda Buyan

2016-07-01

Full Text Available Dok7 is a peripheral membrane protein that is associated with the MuSK receptor tyrosine kinase. Formation of the Dok7/MuSK/membrane complex is required for the activation of MuSK. This is a key step in the complex exchange of signals between neuron and muscle, which lead to neuromuscular junction formation, dysfunction of which is associated with congenital myasthenic syndromes. The Dok7 structure consists of a Pleckstrin Homology (PH domain and a Phosphotyrosine Binding (PTB domain. The mechanism of the Dok7 association with the membrane remains largely unknown. Using multi-scale molecular dynamics simulations we have explored the formation of the Dok7 PH/membrane complex. Our simulations indicate that the PH domain of Dok7 associates with membranes containing phosphatidylinositol phosphates (PIPs via interactions of the β1/β2, β3/β4, and β5/β6 loops, which together form a positively charged surface on the PH domain and interact with the negatively charged headgroups of PIP molecules. The initial encounter of the Dok7 PH domain is followed by formation of additional interactions with the lipid bilayer, and especially with PIP molecules, which stabilizes the Dok7 PH/membrane complex. We have quantified the binding of the PH domain to the model bilayers by calculating a density landscape for protein/membrane interactions. Detailed analysis of the PH/PIP interactions reveal both a canonical and an atypical site to be occupied by the anionic lipid. PH domain binding leads to local clustering of PIP molecules in the bilayer. Association of the Dok7 PH domain with PIP lipids is therefore seen as a key step in localization of Dok7 to the membrane and formation of a complex with MuSK.

Ionospheric scintillation monitoring and modelling

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Mariusz Pozoga

2009-06-01

Full Text Available

px 0.0px 0.0px 0.0px; font: 9.0px Times;">This paper presents a review of the ionospheric scintillation monitoring and modelling by the European groups

px 0.0px 0.0px 0.0px; font: 9.0px Times;">involved in COST 296. Several of these groups have organized scintillation measurement campaigns at low and

px 0.0px 0.0px 0.0px; font: 9.0px Times;">high latitudes. Some characteristic results obtained from the measured data are presented. The paper also addresses the modeling activities: four models, based on phase screen techniques, with different options and application domains are detailed. Finally some new trends for research topics are given. This includes the wavelet analysis, the high latitudes analysis, the construction of scintillation maps and the mitigation techniques.

Molecular Characterization and the Function of Argonaute3 in RNAi Pathway of Plutella xylostella

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Muhammad Salman Hameed

2018-04-01

Full Text Available Argonaute (Ago protein family plays a key role in the RNA interference (RNAi process in different insects including Lepidopteran. However, the role of Ago proteins in the RNAi pathway of Plutella xylostella is still unknown. We cloned an Argonaute3 gene in P. xylostella (PxAgo3 with the complete coding sequence of 2832 bp. The encoded protein had 935 amino acids with an expected molecular weight of 108.9 kDa and an isoelectric point of 9.29. It contained a PAZ (PIWI/Argonaute/Zwile domain and PIWI (P-element-induced whimpy testes domain. PxAgo3 was classified into the Piwi subfamily of Ago proteins with a high similarity of 93.0% with Bombyx mori Ago3 (BmAgo3. The suppression of PxAgo3 by dsPxAgo3 was observed 3 h after treatment and was maintained until 24 h. Knockdown of PxAgo3 decreased the suppression level of PxActin by dsPxActin in P. xylostella cells, while overexpression of PxAgo3 increased the RNAi efficiency. Our results suggest that PxAgo3 play a key role in the double stranded RNA (dsRNA-regulated RNAi pathway in P. xylostella.

A fungal root symbiont modifies plant resistance to an insect herbivore.

Science.gov (United States)

Borowicz, Victoria A

1997-11-01

Vesicular-arbuscular mycorrhizal (VAM) fungi are common root-colonizing symbionts that affect nutrient uptake by plants and can alter plant susceptibility to herbivores. I conducted a factorial experiment to test the hypotheses that colonization by VAM fungi (1) improves soybean (Glycine max) tolerance to grazing by folivorous Mexican bean beetle (Epilachna varivestis), and (2) indirectly affects herbivores by increasing host resistance. Soybean seedlings were inoculated with the VAM fungus Glomus etunicatum or VAM-free filtrate and fertilized with high-[P] or low-[P] fertilizer. After plants had grown for 7 weeks first-instar beetle larvae were placed on bagged leaves. Growth of soybean was little affected by grazing larvae, and no effects of treatments on tolerance of soybeans to herbivores were evident. Colonization by VAM fungus doubled the size of phosphorus-stressed plants but these plants were still half the size of plants given adequate phosphorus. High-[P] fertilizer increased levels of phosphorus and soluble carbohydrates, and decreased levels of soluble proteins in leaves of grazed plants. Colonization of grazed plants by VAM fungus had no significant effect on plant soluble carbohydrates, but increased concentration of phosphorus and decreased levels of proteins in phosphorus-stressed plants to concentrations similar to those of plants given adequate phosphorus. Mexican bean beetle mass at pupation, pupation rate, and survival to eclosion were greatest for beetles reared on phosphorus-stressed, VAM-colonized plants, refuting the hypothesis that VAM colonization improves host plant resistance. VAM colonization indirectly affected performance of Mexician bean beetle larvae by improving growth and nutrition of the host plant.

Grb7 SH2 domain structure and interactions with a cyclic peptide inhibitor of cancer cell migration and proliferation

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Pero Stephanie C

2007-09-01

Full Text Available Abstract Background Human growth factor receptor bound protein 7 (Grb7 is an adapter protein that mediates the coupling of tyrosine kinases with their downstream signaling pathways. Grb7 is frequently overexpressed in invasive and metastatic human cancers and is implicated in cancer progression via its interaction with the ErbB2 receptor and focal adhesion kinase (FAK that play critical roles in cell proliferation and migration. It is thus a prime target for the development of novel anti-cancer therapies. Recently, an inhibitory peptide (G7-18NATE has been developed which binds specifically to the Grb7 SH2 domain and is able to attenuate cancer cell proliferation and migration in various cancer cell lines. Results As a first step towards understanding how Grb7 may be inhibited by G7-18NATE, we solved the crystal structure of the Grb7 SH2 domain to 2.1 Å resolution. We describe the details of the peptide binding site underlying target specificity, as well as the dimer interface of Grb 7 SH2. Dimer formation of Grb7 was determined to be in the μM range using analytical ultracentrifugation for both full-length Grb7 and the SH2 domain alone, suggesting the SH2 domain forms the basis of a physiological dimer. ITC measurements of the interaction of the G7-18NATE peptide with the Grb7 SH2 domain revealed that it binds with a binding affinity of Kd = ~35.7 μM and NMR spectroscopy titration experiments revealed that peptide binding causes perturbations to both the ligand binding surface of the Grb7 SH2 domain as well as to the dimer interface, suggesting that dimerisation of Grb7 is impacted on by peptide binding. Conclusion Together the data allow us to propose a model of the Grb7 SH2 domain/G7-18NATE interaction and to rationalize the basis for the observed binding specificity and affinity. We propose that the current study will assist with the development of second generation Grb7 SH2 domain inhibitors, potentially leading to novel inhibitors of

Solution structure of the human Grb7-SH2 domain/erbB2 peptide complex and structural basis for Grb7 binding to ErbB2

International Nuclear Information System (INIS)

Ivancic, Monika; Daly, Roger J.; Lyons, Barbara A.

2003-01-01

The solution structure of the hGrb7-SH2 domain in complex with a ten amino acid phosphorylated peptide ligand representative of the erbB2 receptor tyrosine kinase (pY1139) is presented as determined by nuclear magnetic resonance methods. The hGrb7-SH2 domain structure reveals the Src homology 2 domain topology consisting of a central β-sheet capped at each end by an α-helix. The presence of a four residue insertion in the region between β-strand E and the EF loop and resulting influences on the SH2 domain/peptide complex structure are discussed. The binding conformation of the erbB2 peptide is in a β-turn similar to that found in phosphorylated tyrosine peptides bound to the Grb2-SH2 domain. To our knowledge this is only the second example of an SH2 domain binding its naturally occurring ligands in a turn, instead of extended, conformation. Close contacts between residues responsible for binding specificity in hGrb7-SH2 and the erbB2 peptide are characterized and the potential effect of mutation of these residues on the hGrb7-SH2 domain structure is discussed

Repurposing Auranofin, Ebselen, and PX-12 as Antimicrobial Agents Targeting the Thioredoxin System

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Holly C. May

2018-03-01

Full Text Available As microbial resistance to drugs continues to rise at an alarming rate, finding new ways to combat pathogens is an issue of utmost importance. Development of novel and specific antimicrobial drugs is a time-consuming and expensive process. However, the re-purposing of previously tested and/or approved drugs could be a feasible way to circumvent this long and costly process. In this review, we evaluate the U.S. Food and Drug Administration tested drugs auranofin, ebselen, and PX-12 as antimicrobial agents targeting the thioredoxin system. These drugs have been shown to act on bacterial, fungal, protozoan, and helminth pathogens without significant toxicity to the host. We propose that the thioredoxin system could serve as a useful therapeutic target with broad spectrum antimicrobial activity.

Triazoles inhibit cholesterol export from lysosomes by binding to NPC1.

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Trinh, Michael N; Lu, Feiran; Li, Xiaochun; Das, Akash; Liang, Qiren; De Brabander, Jef K; Brown, Michael S; Goldstein, Joseph L

2017-01-03

Niemann-Pick C1 (NPC1), a membrane protein of lysosomes, is required for the export of cholesterol derived from receptor-mediated endocytosis of LDL. Lysosomal cholesterol export is reportedly inhibited by itraconazole, a triazole that is used as an antifungal drug [Xu et al. (2010) Proc Natl Acad Sci USA 107:4764-4769]. Here we show that posaconazole, another triazole, also blocks cholesterol export from lysosomes. We prepared P-X, a photoactivatable cross-linking derivative of posaconazole. P-X cross-linked to NPC1 when added to intact cells. Cross-linking was inhibited by itraconazole but not by ketoconazole, an imidazole that does not block cholesterol export. Cross-linking of P-X was also blocked by U18666A, a compound that has been shown to bind to NPC1 and inhibit cholesterol export. P-X also cross-linked to purified NPC1 that was incorporated into lipid bilayer nanodiscs. In this in vitro system, cross-linking of P-X was inhibited by itraconazole, but not by U18666A. P-X cross-linking was not prevented by deletion of the N-terminal domain of NPC1, which contains the initial binding site for cholesterol. In contrast, P-X cross-linking was reduced when NPC1 contained a point mutation (P691S) in its putative sterol-sensing domain. We hypothesize that the sterol-sensing domain has a binding site that can accommodate structurally different ligands.

Preparation of crystals for characterizing the Grb7 SH2 domain before and after complex formation with a bicyclic peptide antagonist.

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Ambaye, Nigus D; Gunzburg, Menachem J; Traore, Daouda A K; Del Borgo, Mark P; Perlmutter, Patrick; Wilce, Matthew C J; Wilce, Jacqueline A

2014-02-01

Human growth factor receptor-bound protein 7 (Grb7) is an adapter protein involved in cell growth, migration and proliferation. It is now recognized that Grb7 is an emerging therapeutic target in specific cancer subtypes. Recently, the discovery of a bicyclic peptide inhibitor that targets the Grb7 SH2 domain, named G7-B1, was reported. In an attempt to probe the foundation of its interaction with Grb7, the crystallization and preliminary data collection of both the apo and G7-B1-bound forms of the Grb7 SH2 domain are reported here. Diffraction-quality crystals were obtained using the hanging-drop vapour-diffusion method. After several rounds of microseeding, crystals of the apo Grb7 SH2 domain were obtained that diffracted to 1.8 Å resolution, while those of the G7-B1-Grb7 SH2 domain complex diffracted to 2.2 Å resolution. The apo Grb7 SH2 domain crystallized in the trigonal space group P63, whereas the G7-B1-Grb7 SH2 domain complex crystallized in the monoclinic space group P21. The experimental aspects of crystallization, crystal optimization and data collection and the preliminary data are reported.

AMP-acetyl CoA synthetase from Leishmania donovani: identification and functional analysis of 'PX4GK' motif.

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Soumya, Neelagiri; Kumar, I Sravan; Shivaprasad, S; Gorakh, Landage Nitin; Dinesh, Neeradi; Swamy, Kayala Kambagiri; Singh, Sushma

2015-04-01

An adenosine monophosphate forming acetyl CoA synthetase (AceCS) which is the key enzyme involved in the conversion of acetate to acetyl CoA has been identified from Leishmania donovani for the first time. Sequence analysis of L. donovani AceCS (LdAceCS) revealed the presence of a 'PX4GK' motif which is highly conserved throughout organisms with higher sequence identity (96%) to lower sequence identity (38%). A ∼ 77 kDa heterologous protein with C-terminal 6X His-tag was expressed in Escherichia coli. Expression of LdAceCS in promastigotes was confirmed by western blot and RT-PCR analysis. Immunolocalization studies revealed that it is a cytosolic protein. We also report the kinetic characterization of recombinant LdAceCS with acetate, adenosine 5'-triphosphate, coenzyme A and propionate as substrates. Site directed mutagenesis of residues in conserved PX4GK motif of LdAceCS was performed to gain insight into its potential role in substrate binding, catalysis and its role in maintaining structural integrity of the protein. P646A, G651A and K652R exhibited more than 90% loss in activity signifying its indispensible role in the enzyme activity. Substitution of other residues in this motif resulted in altered substrate specificity and catalysis. However, none of them had any role in modulation of the secondary structure of the protein except G651A mutant. Copyright © 2015 Elsevier B.V. All rights reserved.

Interrelation between domain structures and polarization switching in hybrid improper ferroelectric Ca3(Mn,Ti)2O7

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Gao, Bin; Huang, Fei-Ting; Wang, Yazhong; Kim, Jae-Wook; Wang, Lihai; Lim, Seong-Joon; Cheong, Sang-Wook

2017-05-01

Ca3Mn2O7 and Ca3Ti2O7 have been proposed as the prototypical hybrid improper ferroelectrics (HIFs), and a significant magnetoelectric (ME) coupling in magnetic Ca3Mn2O7 is, in fact, reported theoretically and experimentally. Although the switchability of polarization is confirmed in Ca3Ti2O7 and other non-magnetic HIFs, there is no report of switchable polarization in the isostructural Ca3Mn2O7. We constructed the phase diagram of Ca3Mn2-xTixO7 through our systematic study of a series of single crystalline Ca3Mn2-xTixO7 (x = 0, 0.1, 1, 1.5, and 2). Using transmission electron microscopy, we have unveiled the unique domain structure of Ca3Mn2O7: the high-density 90° stacking of a- and b-domains along the c-axis due to the phase transition through an intermediate Acca phase and the in-plane irregular wavy ferroelastic twin domains. The interrelation between domain structures and physical properties is unprecedented: the stacking along the c-axis prevents the switching of polarization and causes the irregular in-plane ferroelastic domain pattern. In addition, we have determined the magnetic phase diagram and found complex magnetism of Ca3Mn2O7 with isotropic canted moments. These results lead to negligible observable ME coupling in Ca3Mn2O7 and guide us to explore multiferroics with large ME coupling.

ADAM disintegrin-like domain recognition by the lymphocyte integrins α4β1 and α4β7

OpenAIRE

Bridges, Lance C.; Sheppard, Dean; Bowditch, Ron D.

2005-01-01

The ADAM (a disintegrin and metalloprotease) family of proteins possess both proteolytic and adhesive domains. We have established previously that the disintegrin domain of ADAM28, an ADAM expressed by human lymphocytes, is recognized by the integrin α4β1. The present study characterizes the integrin binding properties of the disintegrin-like domains of human ADAM7, ADAM28 and ADAM33 with the integrins α4β1, α4β7 and α9β1. Cell-adhesion assays demonstrated that, similar to ADAM28, the ADAM7 d...

Pressure-concentration (P-X) diagram for the Ce-Th alloy system

International Nuclear Information System (INIS)

Gu, G.; Vohra, Y.K.; Winand, J.M.; Spirlet, J.C.

1995-01-01

Pressure is an important variable in the phase stability of rare earth and actinide metals and alloys. This is largely due to the enormous change of the f-electron character induced by high pressure. Under high pressure, the increased f-electron overlap and interactions between the f-electrons and the spd conduction electrons are the main causes of the change of f-electron behavior and the relevant phase transformations. Diamond anvil cell techniques now allow for pressures over 300 GPa and this has given new impetus to the field of structural phase transformations. In this paper, the authors report their high pressure measurements on a series of Ce 1-x Th x alloys performed at ambient temperature in a diamond anvil cell using synchrotron x-ray source. In particular, the authors focus their attention on the γ(fcc) to α(fcc) and α to bct (body centered tetragonal) phase transformations caused by application of high pressure. The data is combined with the earlier measurements to construct a P-X diagram for the Ce-Th Alloy system

Molecular Cloning and Characterization of the Calcineurin Subunit A from Plutella xylostella

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Xi'en Chen

2013-10-01

Full Text Available Calcineurin (or PP2B has been reported to be involved in an array of physiological process in insects, and the calcineurin subunit A (CNA plays a central role in calcineurin activity. We cloned the CNA gene from Plutella xylostella (PxCNA. This gene contains an ORF of 1488 bp that encodes a 495 amino acid protein, showing 98%, and 80% identities to the CNA of Bombyx mori, and humans respectively. The full-length of PxCNA and its catalytic domain (CNA1–341, defined as PxCNα were both expressed in Escherichia coli. Purified recombinant PxCNA displayed no phosphatase activity, whereas recombinant PxCNα showed high phosphatase activity with a Km of 4.6 mM and a kcat of 0.66 S−1 against pNPP. It could be activated at different degrees by Mn2+, Ni2+, Mg2+, and Ca2+. The optimum reaction pH was about 7.5 and the optimum reaction temperature was around 45 °C. An in vitro inhibition assay showed that okadaic acid (OA and cantharidin (CTD competitively inhibited recombinant PxCNα activity with the IC50 values of 8.95 μM and 77.64 μM, respectively. However, unlike previous reports, pyrethroid insecticides were unable to inhibit recombinant PxCNα, indicating that the P. xylostella calcineurin appears not to be sensitive to class II pyrethroid insecticides.

Luminescence properties of novel red-emitting phosphor InNb1-xPxO4:Eu3+ for white light emitting-diodes

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Tang An

2015-06-01

Full Text Available InNb1-xPxO4:Eu3+ red phosphors were synthesized by solid-state reaction and their luminescence properties were also studied through photoluminescence spectra. The excitation and emission spectra make it clear that the as-prepared phosphors can be effectively excited by near-ultraviolet (UV 394 nm light and blue 466 nm light to emit strong red light located at 612 nm, due to the Eu3+ transition of 5D0 → 7F2. The luminescence intensity is dependent on phosphorus content, and it achieves the maximum at x = 0.4. Excessive phosphorus in the phosphors can result in reduction of luminescence intensity owing to concentration quenching.With the increasing content of phosphorus, the phosphors are prone to emit pure red light. This shows that the InNb1.6P0.4O4:0.04Eu3+ phosphor may be a potential candidate as a red component for white light emitting-diodes.

Optical probes of symmetry breaking in magnetic and superconducting BaFe2(As1-xPx)2

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Orenstein, Joseph

The discovery of iron pnictide superconductors has opened promising new directions in the effort to fully understand the phenomenon of high-Tc, with a focus on the connections between superconductivity, magnetism, and electronic nematicity. The BaFe2(As1-xPx)2 (P:Ba122) system in particular has received attention because isovalent substitution of As for P generates less disorder than doping on the Fe site. The phase diagram of P:Ba122 is characterized by a line of simultaneous antiferromagnetic (AF) and tetragonal-to-orthorhombic transitions, Ts (x) , that penetrates the superconducting dome at x =0.28, just below optimal doping (xopt = 0.30). In this work, we use spatially-resolved optical polarimetry and photomodulated reflectance to detect linear birefringence and therefore breaking of 4-fold rotational (C4) symmetry. In underdoped (xTsand grows continuously with decreasing T . The birefringence is unidirectional in a large (300 μm x300 μm) field of view, suggesting that C4 breaking in this range of T is caused by residual strain that couples to a diverging nematic susceptibility. Birefringence maps just below Ts (x) show the appearance of domains, indicating the onset of spontaneous symmetry breaking to an AF ground state. Surprisingly, in samples with x>0.28, in which the low T phase is superconducting/ tetragonal rather than AF/orthorhombic, C4 breaking is observed as well, with an abrupt onset and domain formation at 55 K. We tentatively associate these features with a transition to an AF phase induced by residual strain, as previously proposed [H.-H. Kuo et al. Phys. Rev. B86, 134507 (2012)] to account for structure in resistivity vs. T. Time-resolved photomodulation allow us to follow the amplitude of the AF order with time following pulsed photoexcitation. Below Tc the AF order at first weakens , but then strengthens in response to the photoinduced weakening of superconductivity. This complex time evolution is accounted for quantitatively by a model

Investigation of the tensor analyzing power Ayy in the reaction A(d polarized, p)X at large transverse momenta of proton

International Nuclear Information System (INIS)

Afanas'ev, S.V.; Arkhipov, V.V.; Azhgirej, L.S.

1997-01-01

An experiment on the studying of the tensor analyzing power A yy in the reaction A(d polarized, p)X at large transverse momenta of proton using a polarized deuteron beam of LHE accelerator complex has been proposed. These measurements could provide the valuable information on the spin structure of the deuteron at short distances. The estimation of the beam request for SPHERE set-up is performed

Interaction of vesicular-arbuscular mycorrhizal fungi with erosion in an oxisol.

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Habte, M; Fox, R L; Aziz, T; El-Swaify, S A

1988-04-01

The development of vesicular-arbuscular mycorrhizal (VAM) symbiosis was monitored in Leucaena leucocephala grown in an Oxisol subjected to incremental simulated erosion. The density of VAM infective propagules in the soil diminished as the level of simulated erosion (removal of surface soil) was increased from 0 to 50 cm. The level of infection on L. leucocephala roots observed at harvest was not significantly influenced by simulated erosion unless removal of surface soil exceeded 25 cm. Inoculation of this soil and the uneroded soil with Glomus aggregatum enhanced the early onset of infection but did not significantly influence the level of infection observed at the time of harvest. Simulated erosion in excess of 7.5 cm of surface soil removal significantly delayed the development of VAM effectiveness monitored in terms of the P status of L. leucocephala subleaflets and also curtailed the level of maximum effectiveness observed. Decreases in VAM effectiveness were significantly correlated with decreases in soil chemical constituents. However, VAM effectiveness in a soil subjected to 30 cm of surface soil removal was not restored to a significant extent unless the soil was amended with P, even though other nutrients were restored to sufficiency levels. Our results demonstrate that the development of VAM effectiveness is the phase of the VAM symbiosis that is most adversely influenced by simulated erosion and that this effect appears to be caused primarily by insufficient P in the soil solution.

Microstructure within domains of melt-processed YBa2Cu3O7-x superconductors

International Nuclear Information System (INIS)

Alexander, K.B.; Goyal, A.; Kroeger, D.M.; Selvamanickam, V.; Salama, K.

1992-01-01

The microstructure within single domains of melt-processed YBa 2 Cu 3 O 7-x (1:2:3) material has been examined. Rather than composing a ''brick-wall'' structure, the stacked, parallel platelets within the domains are actually portions of a single crystal. A growth mechanism is proposed that is consistent with the observed microstructural features. The anisotropic nature of the growth of 1:2:3 results in gaps separating the platelets. The gaps, however, terminate within domains, resulting in interconnected single-crystalline material. The absence of weak-link behavior for current flow along the c axis and the high critical-current densities observed within domains of melt-processed 1:2:3 material are readily explained by the fact that current flow is solely through single-crystalline material

The phospholipase PNPLA7 functions as a lysophosphatidylcholine hydrolase and interacts with lipid droplets through its catalytic domain.

Science.gov (United States)

Heier, Christoph; Kien, Benedikt; Huang, Feifei; Eichmann, Thomas O; Xie, Hao; Zechner, Rudolf; Chang, Ping-An

2017-11-17

Mammalian patatin-like phospholipase domain-containing proteins (PNPLAs) are lipid-metabolizing enzymes with essential roles in energy metabolism, skin barrier development, and brain function. A detailed annotation of enzymatic activities and structure-function relationships remains an important prerequisite to understand PNPLA functions in (patho-)physiology, for example, in disorders such as neutral lipid storage disease, non-alcoholic fatty liver disease, and neurodegenerative syndromes. In this study, we characterized the structural features controlling the subcellular localization and enzymatic activity of PNPLA7, a poorly annotated phospholipase linked to insulin signaling and energy metabolism. We show that PNPLA7 is an endoplasmic reticulum (ER) transmembrane protein that specifically promotes hydrolysis of lysophosphatidylcholine in mammalian cells. We found that transmembrane and regulatory domains in the PNPLA7 N-terminal region cooperate to regulate ER targeting but are dispensable for substrate hydrolysis. Enzymatic activity is instead mediated by the C-terminal domain, which maintains full catalytic competence even in the absence of N-terminal regions. Upon elevated fatty acid flux, the catalytic domain targets cellular lipid droplets and promotes interactions of PNPLA7 with these organelles in response to increased cAMP levels. We conclude that PNPLA7 acts as an ER-anchored lysophosphatidylcholine hydrolase that is composed of specific functional domains mediating catalytic activity, subcellular positioning, and interactions with cellular organelles. Our study provides critical structural insights into an evolutionarily conserved class of phospholipid-metabolizing enzymes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Androgen receptor regulates nuclear trafficking and nuclear domain residency of corepressor HDAC7 in a ligand-dependent fashion

International Nuclear Information System (INIS)

Karvonen, Ulla; Jaenne, Olli A.; Palvimo, Jorma J.

2006-01-01

In addition to chromosomal proteins, histone deacetylases (HDACs) target transcription factors in transcriptional repression. Here, we show that the class II HDAC family member HDAC7 is an efficient corepressor of the androgen receptor (AR). HDAC7 resided in the cytoplasm in the absence of AR or a cognate ligand, but hormone-occupancy of AR induced nuclear transfer of HDAC7. Nuclear colocalization pattern of AR and HDAC7 was dependent on the nature of the ligand. In the presence of testosterone, a portion of HDAC7 localized to pearl-like nuclear domains, whereas AR occupied with antagonistic ligands cyproterone acetate- or casodex (bicalutamide) recruited HDAC7 from these domains to colocalize with the receptor in speckles and nucleoplasm in a more complete fashion. Ectopic expression of PML-3 relieved the repressive effect of HDAC7 on AR function by sequestering HDAC7 to PML-3 domains. AR acetylation at Lys630/632/633 was not the target of HDAC7 repression, since repression of AR function was independent of these acetylation sites. Moreover, the deacetylase activity of HDAC7 was in part dispensable in the repression of AR function. In sum, our results identify HDAC7 as a novel AR corepressor whose subcellular and subnuclear compartmentalization can be regulated in an androgen-selective manner

Influence of percutaneous stimulation of hepatic region with mid-frequency pulse current on the activity of serum GSH-PX, SOD, T-AOC and the content of malondialdehyde in exercise-induced fatigued soldiers

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Peng-yi DAI

2014-03-01

Full Text Available Objective 　To explore the influence of percutaneous stimulation of the hepatic region with mid-frequency pulsed current on the serum activity of glutathione peroxidase (GSH-PX, superoxide dismutase (SOD and total antioxidant capacity and content of malondialdehyde (MDA in exercise-induced fatigued soldiers. Methods 　Sixty healthy male recruits without training history were randomly divided into control group and stimulation group (n=30. Subjects in both groups received intensive training for 5 weeks (trained from Monday to Saturday, and rest on Sunday to establish an exercise-induced fatigue model. The recruits in stimulation group received rehabilitation therapy of percutaneous stimulation of the hepatic region with mid-frequency pulse current (frequency was 1024Hz, dynamic cycle 1s, stimulation time 20min, output intensity ≤80mA after the training immediately. In every Sunday morning of the 1st, 3rd and 5th week, venous blood samples were obtained from recruits of both groups for determination of the serum activity of GSH-PX, SOD and T-AOC and content of MDA. Results 　In both groups, the serum activity of GSH-PX and T-AOC on 5th weekend was lower than that of 1st and 3rd weekends, and the serum activity of GSH-PX and T-AOC on 3rd weekend was lower than that of 1st weekend (P0.05; the serum MDA content on 5th weekend was higher than that of 3rd and 1st weekends, and the content on 3rd weekend was higher than that of 1st weekend (P<0.01. The activity of GSH-PX, SOD and T-AOC increased and the MDA content decreased on 1st, 3rd and 5th weekends in stimulation group when compared with control group (P<0.05, P<0.01. Conclusions 　The percutaneous stimulation of the hepatic region by mid-frequency pulsed current in exercise-induced fatigued soldiers may improve the activity of antioxidant enzymes in the liver, enhance the function of antioxidant system, promote free radical scavenging, delay the occurrence of and promote the recovery from

The metal chaperone Atox1 regulates the activity of the human copper transporter ATP7B by modulating domain dynamics.

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Yu, Corey H; Yang, Nan; Bothe, Jameson; Tonelli, Marco; Nokhrin, Sergiy; Dolgova, Natalia V; Braiterman, Lelita; Lutsenko, Svetlana; Dmitriev, Oleg Y

2017-11-03

The human transporter ATP7B delivers copper to the biosynthetic pathways and maintains copper homeostasis in the liver. Mutations in ATP7B cause the potentially fatal hepatoneurological disorder Wilson disease. The activity and intracellular localization of ATP7B are regulated by copper, but the molecular mechanism of this regulation is largely unknown. We show that the copper chaperone Atox1, which delivers copper to ATP7B, and the group of the first three metal-binding domains (MBD1-3) are central to the activity regulation of ATP7B. Atox1-Cu binding to ATP7B changes domain dynamics and interactions within the MBD1-3 group and activates ATP hydrolysis. To understand the mechanism linking Atox1-MBD interactions and enzyme activity, we have determined the MBD1-3 conformational space using small angle X-ray scattering and identified changes in MBD dynamics caused by apo -Atox1 and Atox1-Cu by solution NMR. The results show that copper transfer from Atox1 decreases domain interactions within the MBD1-3 group and increases the mobility of the individual domains. The N-terminal segment of MBD1-3 was found to interact with the nucleotide-binding domain of ATP7B, thus physically coupling the domains involved in copper binding and those involved in ATP hydrolysis. Taken together, the data suggest a regulatory mechanism in which Atox1-mediated copper transfer activates ATP7B by releasing inhibitory constraints through increased freedom of MBD1-3 motions. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Nuclear import of high risk HPV16 E7 oncoprotein is mediated by its zinc-binding domain via hydrophobic interactions with Nup62

Energy Technology Data Exchange (ETDEWEB)

Eberhard, Jeremy; Onder, Zeynep; Moroianu, Junona, E-mail: moroianu@bc.edu

2013-11-15

We previously discovered that nuclear import of high risk HPV16 E7 is mediated by a cNLS located within the zinc-binding domain via a pathway that is independent of karyopherins/importins (Angeline et al., 2003; Knapp et al., 2009). In this study we continued our characterization of the cNLS and nuclear import pathway of HPV16 E7. We find that an intact zinc-binding domain is essential for the cNLS function in mediating nuclear import of HPV16 E7. Mutagenesis of cysteine residues to alanine in each of the two CysXXCys motifs involved in zinc-binding changes the nuclear localization of the EGFP-16E7 and 2xEGFP-16E7 mutants. We further discover that a patch of hydrophobic residues, {sub 65}LRLCV{sub 69}, within the zinc-binding domain of HPV16 E7 mediates its nuclear import via hydrophobic interactions with the FG domain of the central channel nucleoporin Nup62. - Highlights: • An intact zinc-binding domain is essential for the nuclear localization of HPV16 E7. • Identification of a hydrophobic patch that is critical for the nuclear import of HPV16 E7. • HPV16 E7 interacts via its zinc-binding domain with the FG domain of Nup62.

Preparation and crystallization of the Grb7 SH2 domain in complex with the G7-18NATE nonphosphorylated cyclic inhibitor peptide

International Nuclear Information System (INIS)

Yap, Min Y.; Wilce, Matthew C. J.; Clayton, Daniel J.; Perlmutter, Patrick; Aguilar, Marie-Isabel; Wilce, Jacqueline A.

2010-01-01

The preparation and successful crystallization of the Grb7 SH2 domain in complex with the specific cyclic peptide inhibitor G7-18NATE are reported. This structure is anticipated to reveal the basis of the binding affinity and specificity and to assist with the development of second-generation inhibitors of Grb7, which is involved in cancer progression. Grb7 is an adapter protein that is involved in signalling pathways that mediate eukaryotic cell proliferation and migration. Its overexpression in several cancer types has implicated it in cancer progression and led to the development of the G7-18NATE cyclic peptide inhibitor. Here, the preparation of crystals of G7-18NATE in complex with its Grb7 SH2 domain target is reported. Crystals of the complex were grown by the hanging-drop vapour-diffusion method using PEG 3350 as the precipitant at room temperature. X-ray diffraction data were collected from crystals to 2.4 Å resolution using synchrotron X-ray radiation at 100 K. The diffraction was consistent with space group P2 1 , with unit-cell parameters a = 52.7, b = 79.1, c = 54.7 Å, α = γ = 90.0, β = 104.4°. The structure of the G7-18NATE peptide in complex with its target will facilitate the rational development of Grb7-targeted cancer therapeutics

Recombinant human B7.2 IgV-like domain expressed in bacteria maintains its co-stimulatory activity in vitro.

Science.gov (United States)

Yan, Xiaocai; Ma, Jun; Zheng, Jin; Lai, Baochang; Geng, Yiping; Wang, Yili; Si, Lüsheng

2002-07-01

To investigate which of the two immunoglobulin (Ig)-like domains, the immunoglobulin variable region homologous domain IgV (hB7.2 IgV) and the immunoglobulin constant region homologous domain IgC (hB7.2 IgC) on the human B7.2 molecule contains receptor binding sites, and to evaluate whether the B7.2 protein expressed in bacteria has biological activity in vitro. Three fragments of hB7.2 IgV,hB7.2 IgC and the complete extracellular region of human B7.2 containing both the IgV and IgC domains,hB7.2 Ig (V+C), were amplified by PCR and subcloned into pGEM-Teasy. Three recombinants,pGEX-4T-3-hB7.2 IgV,pGEX-4T-3-hB7.2 IgC and pGEX-4T-3-hB7.2 Ig (V+C), were generated by cloning the fragments into a prokaryote expression plasmid (pGEX-4T-3) and transformed into the host strain E. coli DH5alpha. The relevant target fusion proteins consisting of GST and hB7.2 IgV,hB7.2 IgC and hB7.2 Ig (V+C), were identified by SDS-PAGE and Western blotting. With the presence of the first signal imitated by anti-CD3 antibody, T cell activation was observed by exposing purified T lymphocytes to each soluble form of the three bacterially-produced human B7.2 fusion proteins by [(3)H]-TdR incorporation. Three recombinant fusion proteins of human B7.2, GST-hB7.2 IgV, GST-hB7.2 IgC and GST-hB7.2 Ig (V+C) were produced and detected in inclusion body form from engineered bacteria. With the first signal present,T lymphocytes proliferated when co-stimulated by bacterially-produced either GST-hB7.2 Ig (V+C) or GST-hB7.2 IgV fusion proteins, but not by GST-hB7.2 IgC. Functional human B7.2 fusion protein can be produced in bacteria. The IgV-like domain of human B7.2 is sufficient for B7.2 to interact with its counter-receptors and co-stimulate T lymphocytes.

Exceptionally tight membrane-binding may explain the key role of the synaptotagmin-7 C ₂ A domain in asynchronous neurotransmitter release

Energy Technology Data Exchange (ETDEWEB)

Voleti, Rashmi; Tomchick, Diana R.; Südhof, Thomas C.; Rizo, Josep

2017-09-18

Synaptotagmins (Syts) act as Ca2+ sensors in neurotransmitter release by virtue of Ca2+-binding to their two C2 domains, but their mechanisms of action remain unclear. Puzzlingly, Ca2+-binding to the C2B domain appears to dominate Syt1 function in synchronous release, whereas Ca2+-binding to the C2A domain mediates Syt7 function in asynchronous release. Here we show that crystal structures of the Syt7 C2A domain and C2AB region, and analyses of intrinsic Ca2+-binding to the Syt7 C2 domains using isothermal titration calorimetry, did not reveal major differences that could explain functional differentiation between Syt7 and Syt1. However, using liposome titrations under Ca2+ saturating conditions, we show that the Syt7 C2A domain has a very high membrane affinity and dominates phospholipid binding to Syt7 in the presence or absence of L-α-phosphatidylinositol 4,5-diphosphate (PIP2). For Syt1, the two Ca2+-saturated C2 domains have similar affinities for membranes lacking PIP2, but the C2B domain dominates binding to PIP2-containing membranes. Mutagenesis revealed that the dramatic differences in membrane affinity between the Syt1 and Syt7 C2A domains arise in part from apparently conservative residue substitutions, showing how striking biochemical and functional differences can result from the cumulative effects of subtle residue substitutions. Viewed together, our results suggest that membrane affinity may be a key determinant of the functions of Syt C2 domains in neurotransmitter release.

The Effect of Vesicular Arbuscular Mycorrhizal (VAM on Yield and Yield Components of Three Sorghum (Sorghum bicolor Cultivars

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A. Mehraban

2012-10-01

Full Text Available To evaluate the influence of vesicular arbuscular mycorrhizal (VAM on yield and yield components of three sorghum cultivars, a factorial experiment based randomized complete block design with four replications was carried out in 2007, at the Agricultural Research Center of Zahak, Iran. The treatments were different mycorrhiza species in three levels: without mycorrhiza (M1, Glomus etanicatum (M2 and G. mosseae(M3 and three cultivars of sorghum: local cultivars (C1, KGS25 (C2 and KGS29 (C3. The results showed that all of the traits measured were increased by inoculation of cultivars with mycorrhiza. The highest plant height (165.1 cm, stem diameter (1.61 cm, flag leaf length (27.22 cm, flag leaf width (3.67 cm and ear width (5.00 cm was obtained by inoculation of seed with Glumus etanicatum, and highest ear length (19.21 cm, ear number (2.51, seed number per ear (10252.11, 1000-seed weight (17.56 g and grain yield (1967.32 kg/ha by using Glumus mossea. The highest leaf width and length belonged to local cultivar, and the highest seed yield to KGS 29 cultivar. However, differences of other traits among sorghum cultivars were not significant. Based on the experimental results it can be concluded that highest grain yield may be obtained by inoculating seeds of KGS 29 with Glumus mossea.

Chitosan Nanoparticles Attenuate Hydrogen Peroxide-Induced Stress Injury in Mouse Macrophage RAW264.7 Cells

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Zi-Rong Xu

2013-09-01

Full Text Available This study was carried out to investigate the protective effects of chitosan nanoparticles (CNP against hydrogen peroxide (H2O2-induced oxidative damage in murine macrophages RAW264.7 cells. After 24 h pre-incubation with CNP (25–200 μg/mL and chitosan (CS (50–200 μg/mL, as controls, the viability loss in RAW264.7 cells induced by H2O2 (500 μM for 12 h was markedly restored in a concentration-dependent manner as measured by MTT assay (P < 0.05 and decreased in cellular LDH release (P < 0.05. Moreover, CNP also exerted preventive effects on suppressing the production of lipid peroxidation such as malondialdehyde (MDA (P < 0.05, restoring activities of endogenous antioxidant including superoxide dismutase (SOD, and glutathione peroxidase (GSH-Px (P < 0.05, along with increasing total antioxidant capacity (T-AOC (P < 0.05. In addition, pre-incubation of CNP with RAW264.7 cells for 24 h resulted in the increase of the gene expression level of endogenous antioxidant enzymes, such as MnSOD and GSH-Px (P < 0.05. At the same concentration, CNP significantly decreased LDH release and MDA (P < 0.05 as well as increased MnSOD, GSH-Px, and T-AOC activities (P < 0.05 as compared to CS. Taken together, our findings suggest that CNP can more effectively protect RAW264.7 cells against oxidative stress by H2O2 as compared to CS, which might be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.

Varying Eu2+ magnetic order by chemical pressure in EuFe2(As1-xPx)2

Science.gov (United States)

Zapf, S.; Wu, D.; Bogani, L.; Jeevan, H. S.; Gegenwart, P.; Dressel, M.

2011-10-01

Based on low-field magnetization measurements on a series of single crystals, we present a scheme of the Eu2+ spin alignment in EuFe2(As1-xPx)2. We explain observations of the Eu2+ ordering previously reported, reconciling different existing phase diagrams. The magnetic moments of the Eu2+ ions are slightly canted, yielding a ferromagnetic contribution along the c direction that becomes stronger with pressure, until superconductivity sets in. The spin-density wave as well as the superconducting phase coexist with an antiferromagnetic interlayer coupling of the canted spins. Reducing the interlayer distance finally leads to a ferromagnetic Eu2+ interlayer coupling and to the suppression of superconductivity.

The nuclear localization of low risk HPV11 E7 protein mediated by its zinc binding domain is independent of nuclear import receptors

International Nuclear Information System (INIS)

Piccioli, Zachary; McKee, Courtney H.; Leszczynski, Anna; Onder, Zeynep; Hannah, Erin C.; Mamoor, Shahan; Crosby, Lauren; Moroianu, Junona

2010-01-01

We investigated the nuclear import of low risk HPV11 E7 protein using 1) transfection assays in HeLa cells with EGFP fusion plasmids containing 11E7 and its domains and 2) nuclear import assays in digitonin-permeabilized HeLa cells with GST fusion proteins containing 11E7 and its domains. The EGFP-11E7 and EGFP-11cE7 39-98 localized mostly to the nucleus. The GST-11E7 and GST-11cE7 39-98 were imported into the nuclei in the presence of either Ran-GDP or RanG19V-GTP mutant and in the absence of nuclear import receptors. This suggests that 11E7 enters the nucleus via a Ran-dependent pathway, independent of nuclear import receptors, mediated by a nuclear localization signal located in its C-terminal domain (cNLS). This cNLS contains the zinc binding domain consisting of two copies of Cys-X-X-Cys motif. Mutagenesis of Cys residues in these motifs changed the localization of the EGFP-11cE7/-11E7 mutants to cytoplasmic, suggesting that the zinc binding domain is essential for nuclear localization of 11E7.

Flavonoids released naturally from alfalfa promote development of symbiotic glomus spores in vitro.

Science.gov (United States)

Tsai, S M; Phillips, D A

1991-05-01

Because flavonoids from legumes induce transcription of nodulation genes in symbiotic rhizobial bacteria, it is reasonable to test whether these compounds alter the development of vesicular-arbuscular mycorrhizal (VAM) fungi that infect those plants. Quercetin-3-O-galactoside, the dominant flavonoid released naturally from alfalfa (Medicago sativa L.) seeds, promoted spore germination of Glomus etunicatum and Glomus macrocarpum in vitro. Quercetin produced the maximum increases in spore germination, hyphal elongation, and hyphal branching in G. etunicatum at 1 to 2.5 muM concentrations. Two flavonoids exuded from alfalfa roots, 4',7-dihydroxyflavone and 4',7-dihydroxyflavanone, also enhanced spore germination of this fungal species. Formononetin, an isoflavone that is released from stressed alfalfa roots, inhibited germination of both Glomus species. These in vitro results suggest that plant flavonoids may facilitate or regulate the development of VAM symbioses and offer new hope for developing pure, plant-free cultures of VAM fungi.

Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

OpenAIRE

Suciatmih Suciatmih

2003-01-01

In order to describe the vesicular-arbuscular mycorrhizal (VAM) status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2%) high level, 32 (66.7%) medium level, and 2(4.1%) low level respectively.

Role of the transmembrane domain of FXYD7 in structural and functional interactions with Na,K-ATPase.

Science.gov (United States)

Li, Ciming; Crambert, Gilles; Thuillard, Delphine; Roy, Sophie; Schaer, Danièle; Geering, Käthi

2005-12-30

Members of the FXYD family are tissue-specific regulators of the Na,K-ATPase. Here, we have investigated the contribution of amino acids in the transmembrane (TM) domain of FXYD7 to the interaction with Na,K-ATPase. Twenty amino acids of the TM domain were replaced individually by tryptophan, and combined mutations and alanine insertion mutants were constructed. Wild type and mutant FXYD7 were expressed in Xenopus oocytes with Na,K-ATPase. Mutational effects on the stable association with Na,K-ATPase and on the functional regulation of Na,K-ATPase were determined by co-immunoprecipitation and two-electrode voltage clamp techniques, respectively. Most residues important for the structural and functional interaction of FXYD7 are clustered in a face of the TM helix containing the two conserved glycine residues, but others are scattered over two-thirds of the FXYD TM helix. Ile-35, Ile-43, and Ile-44 are only involved in the stable association with Na,K-ATPase. Glu-26, Met-30, and Ile-44 are important for the functional effect and/or the efficient association of FXYD7 with Na,K-ATPase, consistent with the prediction that these amino acids contact TM domain 9 of the alpha subunit (Li, C., Grosdidier, A., Crambert, G., Horisberger, J.-D., Michielin, O., and Geering, K. (2004) J. Biol. Chem. 279, 38895-38902). Several amino acids that are not implicated in the efficient association of FXYD7 with the Na,K-ATPase are specifically involved in the functional effect of FXYD7. Leu-32 and Phe-37 influence the apparent affinity for external K+, whereas Val-28 and Ile-42 are implicated in the apparent affinity for both external K+ and external Na+. These amino acids act in a synergistic way. These results highlight the important structural and functional role of the TM domain of FXYD7 and delineate the determinants that mediate the complex interactions of FXYD7 with Na,K-ATPase.

Virtual Instrument for Determining Rate Constant of Second-Order Reaction by pX Based on LabVIEW 8.0.

Science.gov (United States)

Meng, Hu; Li, Jiang-Yuan; Tang, Yong-Huai

2009-01-01

The virtual instrument system based on LabVIEW 8.0 for ion analyzer which can measure and analyze ion concentrations in solution is developed and comprises homemade conditioning circuit, data acquiring board, and computer. It can calibrate slope, temperature, and positioning automatically. When applied to determine the reaction rate constant by pX, it achieved live acquiring, real-time displaying, automatical processing of testing data, generating the report of results; and other functions. This method simplifies the experimental operation greatly, avoids complicated procedures of manual processing data and personal error, and improves veracity and repeatability of the experiment results.

Interactions between Metal-binding Domains Modulate Intracellular Targeting of Cu(I)-ATPase ATP7B, as Revealed by Nanobody Binding*

Science.gov (United States)

Huang, Yiping; Nokhrin, Sergiy; Hassanzadeh-Ghassabeh, Gholamreza; Yu, Corey H.; Yang, Haojun; Barry, Amanda N.; Tonelli, Marco; Markley, John L.; Muyldermans, Serge; Dmitriev, Oleg Y.; Lutsenko, Svetlana

2014-01-01

The biologically and clinically important membrane transporters are challenging proteins to study because of their low level of expression, multidomain structure, and complex molecular dynamics that underlies their activity. ATP7B is a copper transporter that traffics between the intracellular compartments in response to copper elevation. The N-terminal domain of ATP7B (N-ATP7B) is involved in binding copper, but the role of this domain in trafficking is controversial. To clarify the role of N-ATP7B, we generated nanobodies that interact with ATP7B in vitro and in cells. In solution NMR studies, nanobodies revealed the spatial organization of N-ATP7B by detecting transient functionally relevant interactions between metal-binding domains 1–3. Modulation of these interactions by nanobodies in cells enhanced relocalization of the endogenous ATP7B toward the plasma membrane linking molecular and cellular dynamics of the transporter. Stimulation of ATP7B trafficking by nanobodies in the absence of elevated copper provides direct evidence for the important role of N-ATP7B structural dynamics in regulation of ATP7B localization in a cell. PMID:25253690

The Relative Influence of Metal Ion Binding Sites in the I-like Domain and the Interface with the Hybrid Domain on Rolling and Firm Adhesion by Integrin α4β7*

OpenAIRE

Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A.

2004-01-01

We examined the effect of conformational change at the β7 I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin α4β7. An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the α4β7 headpiece. Wild-type α4β7 mediates rolling adhesion in Ca2+ and Ca2+/Mg2+ but firm adhesion in Mg2+ and Mn2+. Stabilizing the ope...

Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

Directory of Open Access Journals (Sweden)

Suciatmih Suciatmih

2003-06-01

Full Text Available In order to describe the vesicular-arbuscular mycorrhizal (VAM status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2% high level, 32 (66.7% medium level, and 2(4.1% low level respectively.

Interactive effects of aluminum, phosphorus and mycorrhizae on growth and nutrient uptake of Panicum virgatum L. (Poaceae).

Science.gov (United States)

Koslowsky, S D; Boener, R E

1989-01-01

The effects of Al on Panicum virgatum (switchgrass), a widespread perennial grass, were determined in relation to factors which might interact with Al in the soil. Plants were grown for 8 weeks in sand culture and were treated with 3 Al levels (0.5, 2.0, 5.0 mM), 2 P levels (0.065, 0.161 mM), 2 inoculum types (vesicular-arbuscular mycorrhizal (VAM) inoculum or VAM-free soil inoculum) and 2 inoculum sources (a high Al forest in NY or a low Al forest in Ohio) in a factorial design. Plant growth decreased with increasing Al and increased with increasing P, but the Al effect was less at high P than low P. VAM-inoculated plants outgrew non-VAM plants, especially at low and medium Al levels. Total P and Ca uptake decreased with increasing Al concentration, especially at low P levels. VAM inoculation did not result in increased P uptake at any Al level though VAM plants took up significantly more Ca than non-VAM plants at any Al level. VAM plants had lower tissue Al concentrations and took up less Al than non-VAM plants; Al uptake increased with increasing soil Al in non-VAM plants but not in VAM plants. Plants given inoculum from the high Al site had significantly lower tissue Al than plants given the low Al site inoculum, regardless of VAM status. We conclude that the presence of a VAM infection, moderate levels of soil P, and the source of the inoculum can reduce the effects of soluble Al. We discuss potential physiological and edaphic mechanisms by which Al may be immobilized and Ca availability increased in the presence of VAM fungi and other soil microflora.

Existence of solutions for a fourth order eigenvalue problem ] {Existence of solutions for a fourth order eigenvalue problem with variable exponent under Neumann boundary conditions

Directory of Open Access Journals (Sweden)

Khalil Ben Haddouch

2016-04-01

Full Text Available In this work we will study the eigenvalues for a fourth order elliptic equation with $p(x$-growth conditions $\\Delta^2_{p(x} u=\\lambda |u|^{p(x-2} u$, under Neumann boundary conditions, where $p(x$ is a continuous function defined on the bounded domain with $p(x>1$. Through the Ljusternik-Schnireleman theory on $C^1$-manifold, we prove the existence of infinitely many eigenvalue sequences and $\\sup \\Lambda =+\\infty$, where $\\Lambda$ is the set of all eigenvalues.

The relative influence of metal ion binding sites in the I-like domain and the interface with the hybrid domain on rolling and firm adhesion by integrin alpha4beta7.

Science.gov (United States)

Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A

2004-12-31

We examined the effect of conformational change at the beta(7) I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin alpha(4)beta(7). An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the alpha(4) beta(7) headpiece. Wild-type alpha(4)beta(7) mediates rolling adhesion in Ca(2+) and Ca(2+)/Mg(2+) but firm adhesion in Mg(2+) and Mn(2+). Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn(2+), confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn(2+). Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion.

Novel nonphosphorylated peptides with conserved sequences selectively bind to Grb7 SH2 domain with affinity comparable to its phosphorylated ligand.

Directory of Open Access Journals (Sweden)

Dan Zhang

Full Text Available The Grb7 (growth factor receptor-bound 7 protein, a member of the Grb7 protein family, is found to be highly expressed in such metastatic tumors as breast cancer, esophageal cancer, liver cancer, etc. The src-homology 2 (SH2 domain in the C-terminus is reported to be mainly involved in Grb7 signaling pathways. Using the random peptide library, we identified a series of Grb7 SH2 domain-binding nonphosphorylated peptides in the yeast two-hybrid system. These peptides have a conserved GIPT/K/N sequence at the N-terminus and G/WD/IP at the C-terminus, and the region between the N-and C-terminus contains fifteen amino acids enriched with serines, threonines and prolines. The association between the nonphosphorylated peptides and the Grb7 SH2 domain occurred in vitro and ex vivo. When competing for binding to the Grb7 SH2 domain in a complex, one synthesized nonphosphorylated ligand, containing the twenty-two amino acid-motif sequence, showed at least comparable affinity to the phosphorylated ligand of ErbB3 in vitro, and its overexpression inhibited the proliferation of SK-BR-3 cells. Such nonphosphorylated peptides may be useful for rational design of drugs targeted against cancers that express high levels of Grb7 protein.

Enzyme-linked immunosorbent serum assay specific for the 7S domain of Collagen Type IV (P4NP 7S)

DEFF Research Database (Denmark)

Leeming, Diana J; Nielsen, Mette J; Dai, Yueqin

2012-01-01

Aim:  The present study describes the ability of a newly developed N-terminal pro-peptides of type IV collagen 7S domain (P4NP 7S) competitive enzyme-linked immunosorbent assay (ELISA) for describing liver fibrosis. The assay applies a monoclonal antibody specific for a PIVNP 7S epitope 100...... were significantly elevated in rat with liver fibrosis as seen by histology (CCL4: 283% elevated in the highest quartile of total hepatic collagen compared with controls, P = 0.001; BDL: 183% elevated at week 4 compared with sham, P type IV collagen...... expression in BDL rats (r = 0.49, P serum assay specific for P4NP 7S was highly related to liver fibrosis...

The Relative Influence of Metal Ion Binding Sites in the I-like Domain and the Interface with the Hybrid Domain on Rolling and Firm Adhesion by Integrin α4β7*

Science.gov (United States)

Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A.

2015-01-01

We examined the effect of conformational change at the β7 I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin α4β7. An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the α4β7 headpiece. Wild-type α4β7 mediates rolling adhesion in Ca2+ and Ca2+/Mg2+ but firm adhesion in Mg2+ and Mn2+. Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn2+, confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn2+. Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion. PMID:15448154

The IgV domain of human B7-2 (CD86) is sufficient to co-stimulate T lymphocytes and induce cytokine secretion.

Science.gov (United States)

Rennert, P; Furlong, K; Jellis, C; Greenfield, E; Freeman, G J; Ueda, Y; Levine, B; June, C H; Gray, G S

1997-06-01

B7-1 (CD80) and B7-2 (CD86) are genetically and structurally related molecules expressed on antigen-presenting cells. Both bind CD28 to co-stimulate T lymphocytes, resulting in proliferation and cytokine production. The extracellular portions of B7-1 and B7-2 which bind to CD28 and CTLA-4 are related to Ig variable (V) and Ig constant (C) domain sequences. Recent reports have described splice variant forms of B7 proteins which occur in vivo and are of unknown function. Here we describe soluble recombinant forms of B7-1 and B7-2 containing either both of the Ig-like extracellular domains or the individual IgV or IgC domains coupled to an Ig Fc tail. Soluble B7-1 and B7-2 bind to CD28 and CTLA-4, and effectively co-stimulate T lymphocytes resulting in their proliferation and the secretion of cytokines. Furthermore, the IgV domain of B7-2 binds CD28 and CTLA-4, competes with B7-1 and B7-2 for binding to these receptors, and co-stimulates T lymphocytes. Cross-linked soluble B7-2v was the most potent co-stimulatory molecule tested and was active at a concentration approximately 100-fold lower than cross-linked soluble B7-1 or B7-2 proteins. When bound to tosyl-activated beads, B7-2v was capable of sustaining multiple rounds of T cell expansion. These data complement the description of naturally occurring variants to suggest that T cell co-stimulation in vivo may be regulated by soluble or truncated forms of B7 proteins.

Limited cross-reactivity among domains of the Plasmodium falciparum clone 3D7 erythrocyte membrane protein 1 family

DEFF Research Database (Denmark)

Joergensen, Louise; Turner, Louise; Magistrado, Pamela

2006-01-01

The var gene-encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family is responsible for antigenic variation and sequestration of infected erythrocytes during malaria. We have previously grouped the 60 PfEMP1 variants of P. falciparum clone 3D7 into groups A and B/A (category A......) and groups B, B/C, and C (category non-A). Expression of category A molecules is associated with severe malaria, and that of category non-A molecules is associated with uncomplicated malaria and asymptomatic infection. Here we assessed cross-reactivity among 60 different recombinant PfEMP1 domains derived...... from clone 3D7 by using a competition enzyme-linked immunosorbent assay and a pool of plasma from 63 malaria-exposed Tanzanian individuals. We conclude that naturally acquired antibodies are largely directed toward epitopes varying between different domains with a few, mainly category A, domains...

Can Fertilization of Soil Select Less Mutualistic Mycorrhizae?

Science.gov (United States)

Johnson, Nancy Collins

1993-11-01

It has been noted previously that nutrient-stressed plants generally release more soluble carbohydrate in root exudates and consequently support more mycorrhizae than plants supplied with ample nutrients. Fertilization may select strains of vesicular-arbuscular mycorrhizal (VAM) fungi that are inferior mutualists if the same characteristics that make a VAM fungus successful in roots with a lowered carbohydrate content also reduce the benefits that the fungus provides a host plant. This two-phase study experimentally tests the hypothesis that fertilizing low-nutrient soil selects VAM fungi that are inferior mutualists. The first phase examines the effects of chemical fertilizers on the species composition of VAM fungal communities in long-term field plots. The second phase measures the effects of VAM fungal assemblages from fertilized and unfertilized plots on big bluestem grass grown in a greenhouse. The field results indicate that 8 yr of fertilization altered the species composition of VAM fungal communities. Relative abundance of Gigaspora gigantea, Gigaspora margarita, Scutellispora calospora, and Glomus occultum decreased while Glomus intraradix increased in response to fertilization. Results from the greenhouse experiment show that big bluestem colonized with VAM fungi from fertilized soil were smaller after 1 mo and produced fewer inflorescences at 3 mo than big bluestem colonized with VAM fungi from unfertilized soil. Fungal structures within big bluestem roots suggest that VAM fungi from fertilized soil exerted a higher net carbon cost on their host than VAM fungi from unfertilized soil. VAM fungi from fertilized soil produced fewer hyphae and arbuscules (and consequently provided their host with less inorganic nutrients from the soil) and produced as many vesicles (and thus provisioned their own storage structures at the same level) as fungi from unfertilized soil. These results support the hypothesis that fertilization selects VAM fungi that are inferior

Interactions of Vesicular-Arbuscular Mycorrhizal Fungi, Phosphorus, and Heterodera glycines on Soybean.

Science.gov (United States)

Tylka, G L; Hussey, R S; Roncadori, R W

1991-01-01

Effects of vesicular-arbuscular mycorrhizal (VAM) fungi and soil phosphorus (P) fertility on parasitism of soybean cultivars Bragg and Wright by soybean cyst nematode (SCN) were investigated in field micropiot and greenhouse experiments. VAM fungi increased height of both cultivars and yield of Wright in microplot studies in 1986 and 1987. Conversely, yield of mycorrhizal and nonmycorrhizal plants of both cultivars was suppressed by SCN. Soil population densities of SCN were unaffected by VAM fungi in 1986 but were greater in microplots infested with VAM fungi than in control microplots in 1987. Growth of Wright soybean was stimulated by VAM fungi and suppressed by SCN in greenhouse experiments. The effect of VAM fungi on SCN varied with time. Numbers of SCN in roots and soil were decreased by VAM fungi by as much as 73% at the highest SCN inoculum level through 49 days after planting. Later, however, SCN numbers were usually comparable on mycorrhizal and nonmycorrhizal plants. Soil P fertility generally had no effect on SCN. Results of a split-root experiment indicated that VAM fungal suppression of SCN was not systemic.

Energy gaps, valence and conduction charge densities and optical properties of GaAs1‑xPx

Science.gov (United States)

Al-Hagan, O. A.; Algarni, H.; Bouarissa, N.; Alhuwaymel, T. F.; Ajmal Khan, M.

2018-04-01

The electronic structure and its derived valence and conduction charge distributions along with the optical properties of zinc-blende GaAs1‑xPx ternary alloys have been studied. The calculations are performed using a pseudopotential approach under the virtual crystal approximation (VCA) which takes into account the compositional disorder effect. Our findings are found to be generally in good accord with experiment. The composition dependence of direct and indirect bandgaps showed a clear bandgap bowing. The nature of the gap is found to depend on phosphorous content. The bonding and ionicity of the material of interest have been examined in terms of the anti-symmetric gap and charge densities. The variation in the optical constants versus phosphorous concentration has been discussed. The present investigation may give a useful applications in infrared and visible spectrum light emitters.

Magnetic domain structure in a metamagnetic shape memory alloy Ni45Co5Mn36.7In13.3

International Nuclear Information System (INIS)

Murakami, Y.; Yano, T.; Shindo, D.; Kainuma, R.; Oikawa, K.; Ishida, K.

2006-01-01

Correlation between the magnetism and the martensitic transformation in Ni 45 Co 5 Mn 36.7 In 13.3 has been revealed by electron holography and Lorentz microscopy. The parent phase exhibits typical closure magnetic domains due to low magnetocrystalline anisotropy. Upon cooling, the magnetic flux density of the parent phase monotonically increases, while the magnetic domain structure remains almost unchanged; in other words, the effect of premartensitic lattice modulation appears to be small in this alloy. The magnetic domains disappear immediately when the martensitic transformation occurs

The role of mycorrhizal fungi and microsites in primary succession on Mount St. Helens.

Science.gov (United States)

Titus, J; Del Moral, R

1998-03-01

This study was designed to examine the role of vesicular-arbuscular mycorrhizae (VAM) and microsites on the growth of pioneer species. Flat, rill, near-rock, and dead lupine microsites were created in plots in barren areas of the Pumice Plain of Mount St. Helens. VAM propagules were added to the soil in half of the plots. Six pioneer species were planted into both VAM and non-VAM inoculated microsites. Plants in dead lupine microsites were greater in biomass than those in flat, rill, and near-rock microsites. Significant effects of VAM on plant biomass did not occur. Microsites continue to be important to plant colonization on the Pumice Plain, but VAM do not yet appear to play an important role. This may be due to limited nutrient availability and the facultatively mycotrophic nature of the colonizing plant species. It is unlikely that VAM play an important role in successional processes in newly emplaced nutrient-poor surfaces.

Inter-domain synergism is required for efficient feeding of cellulose chain into active site of cellobiohydrolase Cel7A

DEFF Research Database (Denmark)

Kont, Riin; Kari, Jeppe; Borch, Kim

2016-01-01

systems. TrCel7A consists of catalytic domain (CD) and a smaller carbohydrate binding module (CBM) connected through the glycosylated linker peptide. A tunnel shaped active site rests in the CD and contains 10 glucose unit binding sites. The active site of TrCel7A is lined with four Trp residues with two...... to Ala substitution on on-rates was strongly dependent on the presence of the CBM-linker. This compensation between CBM-linker and Trp-38 indicates synergism between CBM-linker and CD in feeding the cellulose chain into the active site. The inter-domain synergism was pre-requisite for the efficient......Structural polysaccharides like cellulose and chitin are abundant and their enzymatic degradation to soluble sugars is an important route in green chemistry. Processive glycoside hydrolases (GHs), like cellobiohydrolase Cel7A of Trichoderma reesei (TrCel7A) are key components of efficient enzyme...

Resistance Responses of Potato to Vesicular-Arbuscular Mycorrhizal Fungi under Varying Abiotic Phosphorus Levels.

Science.gov (United States)

McArthur, D A; Knowles, N R

1992-09-01

In mycorrhizal symbioses, susceptibility of a host plant to infection by fungi is influenced by environmental factors, especially the availability of soil phosphorus. This study describes morphological and biochemical details of interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants, with a particular focus on the physiological basis for P-induced resistance of roots to infection. Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis. The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection. This apparent inhibition of ACC oxidase (ACC(ox)) activity was localized to areas containing infected roots, as demonstrated in split-root studies. Furthermore, leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots. The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots. Moreover, the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature. The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots. Polyphenol oxidase activity of roots did not differ between NM and VAM roots. These results characterize the low resistance response of P-deficient plants to VAM infection. When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis

Nuclear import of cutaneous beta genus HPV8 E7 oncoprotein is mediated by hydrophobic interactions between its zinc-binding domain and FG nucleoporins

Energy Technology Data Exchange (ETDEWEB)

Onder, Zeynep; Moroianu, Junona, E-mail: moroianu@bc.edu

2014-01-20

We have previously discovered and characterized the nuclear import pathways for the E7 oncoproteins of mucosal alpha genus HPVs, type 16 and 11. Here we investigated the nuclear import of cutaneous beta genus HPV8 E7 protein using confocal microscopy after transfections of HeLa cells with EGFP-8E7 and mutant plasmids and nuclear import assays in digitonin-permeabilized HeLa cells. We determined that HPV8 E7 contains a nuclear localization signal (NLS) within its zinc-binding domain that mediates its nuclear import. Furthermore, we discovered that a mostly hydrophobic patch {sub 65}LRLFV{sub 69} within the zinc-binding domain is essential for the nuclear import and localization of HPV8 E7 via hydrophobic interactions with the FG nucleoporins Nup62 and Nup153. Substitution of the hydrophobic residues within the {sub 65}LRLFV{sub 69} patch to alanines, and not R66A mutation, disrupt the interactions between the 8E7 zinc-binding domain and Nup62 and Nup153 and consequently inhibit nuclear import of HPV8 E7. - Highlights: • HPV8 E7 has a cNLS within its zinc-binding domain that mediates its nuclear import. • Discovery of a hydrophobic patch that is critical for the nuclear import of HPV8 E7. • HPV8 E7 nuclear import is mediated by hydrophobic interactions with FG-Nups, Nup62 and Nup153.

Prognostic importance of circulating epidermal growth factor-like domain 7 in patients with metastatic colorectal cancer treated with chemotherapy and bevacizumab

DEFF Research Database (Denmark)

Hansen, Torben Frøstrup; Andersen, Rikke Fredslund; Aalund Olsen, Dorte

2017-01-01

High tumor expression of epidermal growth factor-like domain 7 (EGFL7) has been associated with a poor prognosis in colorectal cancer. The aim of the current study was to investigate the possible prognostic impact of circulating EGFL7 (cir-EGFL7), combined with single nucleotide polymorphism (SNP...

Structure of the TPR domain of AIP: lack of client protein interaction with the C-terminal α-7 helix of the TPR domain of AIP is sufficient for pituitary adenoma predisposition.

Directory of Open Access Journals (Sweden)

Rhodri M L Morgan

Full Text Available Mutations of the aryl hydrocarbon receptor interacting protein (AIP have been associated with familial isolated pituitary adenomas predisposing to young-onset acromegaly and gigantism. The precise tumorigenic mechanism is not well understood as AIP interacts with a large number of independent proteins as well as three chaperone systems, HSP90, HSP70 and TOMM20. We have determined the structure of the TPR domain of AIP at high resolution, which has allowed a detailed analysis of how disease-associated mutations impact on the structural integrity of the TPR domain. A subset of C-terminal α-7 helix (Cα-7h mutations, R304* (nonsense mutation, R304Q, Q307* and R325Q, a known site for AhR and PDE4A5 client-protein interaction, occur beyond those that interact with the conserved MEEVD and EDDVE sequences of HSP90 and TOMM20. These C-terminal AIP mutations appear to only disrupt client-protein binding to the Cα-7h, while chaperone binding remains unaffected, suggesting that failure of client-protein interaction with the Cα-7h is sufficient to predispose to pituitary adenoma. We have also identified a molecular switch in the AIP TPR-domain that allows recognition of both the conserved HSP90 motif, MEEVD, and the equivalent sequence (EDDVE of TOMM20.

Dynamics of vesicular-arbuscular mycorrhizae during old field succession.

Science.gov (United States)

Johnson, Nancy Collins; Zak, Donald R; Tilman, David; Pfleger, F L

1991-05-01

The species composition of vesicular-arbuscular mycorrhizal (VAM) fungal communities changed during secondary succession of abandoned fields based on a field to forest chronosequence. Twenty-five VAM fungal species were identified. Seven species were clearly early successional and five species were clearly late successional. The total number of VAM fungal species did not increase with successional time, but diversity as measured by the Shannon-Wiener index tended to increase, primarily because the community became more even as a single species, Glomus aggregatum, became less dominant in the older sites. Diversity of the VAM fungal community was positively correlated with soil C and N. The density of VAM fungi, as measured by infectivity and total spore count, first increased with time since abandonment and then decreased in the late successional forest sites. Within 12 abandoned fields, VAM fungal density increased with increasing soil pH, H 2 O soluble soil C, and root biomass, but was inversely related to extractable soil P and percent cover of non-host plant species. The lower abundance of VAM fungi in the forest sites compared with the field sites agrees with the findings of other workers and corresponds with a shift in the dominant vegetation from herbaceous VAM hosts to woody ectomycorrhizal hosts.

Dlouhá pamět a její vývoj ve výnosech burzovního indexu PX v letech 1997 - 2009

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2010-01-01

Roč. 58, č. 4 (2010), s. 471-478 ISSN 0032-3233 R&D Projects: GA ČR GD402/09/H045 Grant - others:GAUK(CZ) GAUK 118310; MŠMT(CZ) MŠMT 0021620841 Institutional research plan: CEZ:AV0Z10750506 Keywords : econophysics * long-range dependence * time series analysis * rescaled range * periodogram Subject RIV: AH - Economics Impact factor: 0.650, year: 2010 http://library.utia.cas.cz/separaty/2010/E/kristoufek-long-term memory and its evolution in returns of stock index px between 1997 and 2009.pdf

Transmission of integrin β7 transmembrane domain topology enables gut lymphoid tissue development.

Science.gov (United States)

Sun, Hao; Lagarrigue, Frederic; Gingras, Alexandre R; Fan, Zhichao; Ley, Klaus; Ginsberg, Mark H

2018-04-02

Integrin activation regulates adhesion, extracellular matrix assembly, and cell migration, thereby playing an indispensable role in development and in many pathological processes. A proline mutation in the central integrin β3 transmembrane domain (TMD) creates a flexible kink that uncouples the topology of the inner half of the TMD from the outer half. In this study, using leukocyte integrin α4β7, which enables development of gut-associated lymphoid tissue (GALT), we examined the biological effect of such a proline mutation and report that it impairs agonist-induced talin-mediated activation of integrin α4β7, thereby inhibiting rolling lymphocyte arrest, a key step in transmigration. Furthermore, the α4β7(L721P) mutation blocks lymphocyte homing to and development of the GALT. These studies show that impairing the ability of an integrin β TMD to transmit talin-induced TMD topology inhibits agonist-induced physiological integrin activation and biological function in development. © 2018 Sun et al.

Parametric estimation of P(X > Y) for normal distributions in the context of probabilistic environmental risk assessment.

Science.gov (United States)

Jacobs, Rianne; Bekker, Andriëtte A; van der Voet, Hilko; Ter Braak, Cajo J F

2015-01-01

Estimating the risk, P(X > Y), in probabilistic environmental risk assessment of nanoparticles is a problem when confronted by potentially small risks and small sample sizes of the exposure concentration X and/or the effect concentration Y. This is illustrated in the motivating case study of aquatic risk assessment of nano-Ag. A non-parametric estimator based on data alone is not sufficient as it is limited by sample size. In this paper, we investigate the maximum gain possible when making strong parametric assumptions as opposed to making no parametric assumptions at all. We compare maximum likelihood and Bayesian estimators with the non-parametric estimator and study the influence of sample size and risk on the (interval) estimators via simulation. We found that the parametric estimators enable us to estimate and bound the risk for smaller sample sizes and small risks. Also, the Bayesian estimator outperforms the maximum likelihood estimators in terms of coverage and interval lengths and is, therefore, preferred in our motivating case study.

Alternative splicing of the human gene SYBL1 modulates protein domain architecture of longin VAMP7/TI-VAMP, showing both non-SNARE and synaptobrevin-like isoforms

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De Franceschi Nicola

2011-05-01

Full Text Available Abstract Background The control of intracellular vesicle trafficking is an ideal target to weigh the role of alternative splicing in shaping genomes to make cells. Alternative splicing has been reported for several Soluble N-ethylmaleimide-sensitive factor Attachment protein REceptors of the vesicle (v-SNAREs or of the target membrane (t-SNARES, which are crucial to intracellular membrane fusion and protein and lipid traffic in Eukaryotes. However, splicing has not yet been investigated in Longins, i.e. the most widespread v-SNAREs. Longins are essential in Eukaryotes and prototyped by VAMP7, Sec22b and Ykt6, sharing a conserved N-terminal Longin domain which regulates membrane fusion and subcellular targeting. Human VAMP7/TI-VAMP, encoded by gene SYBL1, is involved in multiple cell pathways, including control of neurite outgrowth. Results Alternative splicing of SYBL1 by exon skipping events results in the production of a number of VAMP7 isoforms. In-frame or frameshift coding sequence modifications modulate domain architecture of VAMP7 isoforms, which can lack whole domains or domain fragments and show variant or extra domains. Intriguingly, two main types of VAMP7 isoforms either share the inhibitory Longin domain and lack the fusion-promoting SNARE motif, or vice versa. Expression analysis in different tissues and cell lines, quantitative real time RT-PCR and confocal microscopy analysis of fluorescent protein-tagged isoforms demonstrate that VAMP7 variants have different tissue specificities and subcellular localizations. Moreover, design and use of isoform-specific antibodies provided preliminary evidence for the existence of splice variants at the protein level. Conclusions Previous evidence on VAMP7 suggests inhibitory functions for the Longin domain and fusion/growth promoting activity for the Δ-longin molecule. Thus, non-SNARE isoforms with Longin domain and non-longin SNARE isoforms might have somehow opposite regulatory functions

Determination of piroxicam in pharmaceutical formulations and urine samples using europium-sensitized luminescence

Energy Technology Data Exchange (ETDEWEB)

Al-Kindy, Salma M.Z. [Department of Chemistry, College of Science, P.O. Box 36, Al-Khod 123, Sultan Qaboos University (Oman)], E-mail: alkindy@squ.edu.om; Suliman, Fakhr Eldin O.; Al-Wishahi, Aisha A.; Al-Lawati, Haidar A.J.; Aoudia, Muhammed [Department of Chemistry, College of Science, P.O. Box 36, Al-Khod 123, Sultan Qaboos University (Oman)

2007-12-15

A simple, selective and sensitive luminescence method for the assay of piroxicam (PX) in aqueous solution is developed. The method is based on the luminescence sensitization of europium (Eu{sup 3+}) by formation of ternary complex with PX in the presence of TOPO and Tween-80 as surfactant. The signal for Eu-PX-TOPO is monitored at {lambda}{sub ex}=359 nm and {lambda}{sub em}=615 nm. Optimum conditions for the formation of the complex in sequential injection analysis (SIA) were 0.01 M Tris buffer, pH 7.5, TOPO 5.0x10{sup -5} M, Tween-80 0.15% and 1.5 mM of Eu{sup 3+}, which allows the determination of 100-1000 ppb of PX with limit of detection (LOD) of 29 ppb. The relative standard deviations of the method range between 0.5% and 3.9% indicating excellent reproducibility of the method. The proposed method was successfully applied for the assay of PX in pharmaceutical formulations and in urine samples. Average recoveries of 100.8{+-}1.7% was obtained in tablet, whereas a recovery of 97.5{+-}2.0% was obtained for the total PX (PX+hydoxy-PX) in urine sample.

Determination of piroxicam in pharmaceutical formulations and urine samples using europium-sensitized luminescence

International Nuclear Information System (INIS)

Al-Kindy, Salma M.Z.; Suliman, Fakhr Eldin O.; Al-Wishahi, Aisha A.; Al-Lawati, Haidar A.J.; Aoudia, Muhammed

2007-01-01

A simple, selective and sensitive luminescence method for the assay of piroxicam (PX) in aqueous solution is developed. The method is based on the luminescence sensitization of europium (Eu 3+ ) by formation of ternary complex with PX in the presence of TOPO and Tween-80 as surfactant. The signal for Eu-PX-TOPO is monitored at λ ex =359 nm and λ em =615 nm. Optimum conditions for the formation of the complex in sequential injection analysis (SIA) were 0.01 M Tris buffer, pH 7.5, TOPO 5.0x10 -5 M, Tween-80 0.15% and 1.5 mM of Eu 3+ , which allows the determination of 100-1000 ppb of PX with limit of detection (LOD) of 29 ppb. The relative standard deviations of the method range between 0.5% and 3.9% indicating excellent reproducibility of the method. The proposed method was successfully applied for the assay of PX in pharmaceutical formulations and in urine samples. Average recoveries of 100.8±1.7% was obtained in tablet, whereas a recovery of 97.5±2.0% was obtained for the total PX (PX+hydoxy-PX) in urine sample

Existence of solutions to n-dimensional pendulum-like equations

Directory of Open Access Journals (Sweden)

Maria Cristina Mariani

2004-10-01

Full Text Available We study the elliptic boundary-value problem $$displaylines{ Delta u + g(x,u = p(x quad hbox{in } Omega cr uig|_{partial Omega} = hbox{ m constant}, quad int_{partialOmega} frac {partial u}{partial u} = 0, }$$ where $g$ is $T$-periodic in $u$, and $Omega subset mathbb{R}^n$ is a bounded domain. We prove the existence of a solution under a condition on the average of the forcing term $p$. Also, we prove the existence of a compact interval $I_p subset mathbb{R}$ such that the problem is solvable for $ilde p(x = p(x + c$ if and only if $cin I_p$.

Does volumetric absorptive microsampling eliminate the hematocrit bias for caffeine and paraxanthine in dried blood samples? A comparative study.

Science.gov (United States)

De Kesel, Pieter M M; Lambert, Willy E; Stove, Christophe P

2015-06-30

Volumetric absorptive microsampling (VAMS) is a novel sampling technique that allows the straightforward collection of an accurate volume of blood (approximately 10μL) from a drop or pool of blood by dipping an absorbent polymeric tip into it. The resulting blood microsample is dried and analyzed as a whole. The aim of this study was to evaluate the potential of VAMS to overcome the hematocrit bias, an important issue in the analysis of dried blood microsamples. An LC-MS/MS method for analysis of the model compounds caffeine and paraxanthine in VAMS samples was fully validated and fulfilled all pre-established criteria. In conjunction with previously validated procedures for dried blood spots (DBS) and blood, this allowed us to set up a meticulous comparative study in which both compounds were determined in over 80 corresponding VAMS, DBS and liquid whole blood samples. These originated from authentic human patient samples, covering a wide hematocrit range (0.21-0.50). By calculating the differences with reference whole blood concentrations, we found that analyte concentrations in VAMS samples were not affected by a bias that changed over the evaluated hematocrit range, in contrast to DBS results. However, VAMS concentrations tend to overestimate whole blood concentrations, as a consistent positive bias was observed. A different behavior of VAMS samples prepared from incurred and spiked blood, combined with a somewhat reduced recovery of caffeine and paraxanthine from VAMS tips at high hematocrit values, an effect that was not observed for DBS using a very similar extraction procedure, was found to be at the basis of the observed VAMS-whole blood deviations. Based on this study, being the first in which the validity and robustness of VAMS is evaluated by analyzing incurred human samples, it can be concluded that VAMS effectively assists in eliminating the effect of hematocrit. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Pruebas de velocidad aeróbica máxima con jóvenes futbolistas. Control y programación de la intensidad de los entrenamientos

Directory of Open Access Journals (Sweden)

Philippe Campillo

2013-09-01

Full Text Available Se ha realizado un estudio comparativo para analizar la importancia del entrenamiento intermitente, más precisamente la utilización de la velocidad aeróbica máxima (VAM intermitente en la práctica del fútbol. Se ha evaluado la VAM continua con la prueba VAMEVAL (evaluación de la velocidad máxima aeróbica y la VAM intermitente con la prueba 45-15 con ayuda de 21 jóvenes futbolistas. Teniendo en cuenta los resultados se han formado dos grupos homogéneos que realizan un ciclo de siete semanas de entrenamiento específico con el objetivo de desarrollar la PMA. La intensidad del entrenamiento del grupo 1 tiene como referencia el nivel máximo de la VAM continua y el de la VAM intermitente para el grupo 2. Para el conjunto de los jugadores, y para cada grupo, se observa una diferencia significativa inicial (p < 0,001 entre la VAM intermitente (16,02 ± 1,21 km/h y la VAM continua (14,12 ± 1,06 km/h. Finalizado el ciclo se mantienen las mismas diferencias entre las VAM intermitentes y continuas. Sin embargo, para el grupo 1 no hay diferencias significativas entre las dos pruebas 45-15 inicial y final; por el contrario, para el grupo 2 existe una clara diferencia (p < 0,01 entre las dos pruebas intermitentes (15,86 ± 1,50 km/h / 17,0 ± 0,97 km/h. Aunque los dos grupos han mejorado su VAM continua se observa un aumento superior de la velocidad en el grupo 2. Es muy importante tener en cuenta los resultados de las pruebas de VAM continua y sobre todo intermitente para programar y adaptar con precisión la intensidad de los entrenamientos, puesto que existen diferencias que no siempre se valoran.

Predicting Teacher Value-Added Results in Non-Tested Subjects Based on Confounding Variables: A Multinomial Logistic Regression

Science.gov (United States)

Street, Nathan Lee

2017-01-01

Teacher value-added measures (VAM) are designed to provide information regarding teachers' causal impact on the academic growth of students while controlling for exogenous variables. While some researchers contend VAMs successfully and authentically measure teacher causality on learning, others suggest VAMs cannot adequately control for exogenous…

Effects of transcranial direct current stimulation on hemichannel pannexin-1 and neural plasticity in rat model of cerebral infarction.

Science.gov (United States)

Jiang, T; Xu, R X; Zhang, A W; Di, W; Xiao, Z J; Miao, J Y; Luo, N; Fang, Y N

2012-12-13

The aim of this study was to investigate the effects of transcranial direct current stimulation (TDCS) on hemichannel pannexin-1 (PX1) in cortical neurons and neural plasticity, and explore the optimal time window of TDCS therapy after stroke. Adult male Sprague-Dawley rats (n=90) were randomly assigned to sham operation, middle cerebral artery occlusion (MCAO), and TDCS groups, and underwent sham operation, unilateral middle cerebral artery (MCA) electrocoagulation, and unilateral MCA electrocoagulation plus TDCS (daily anodal and cathodal 10 Hz, 0.1 mA TDCS for 30 min beginning day 1 after stroke), respectively. Motor function was assessed using the beam walking test (BWT), and density of dendritic spines (DS) and PX1 mRNA expression were compared among groups on days 3, 7, and 14 after stroke. Effects of PX1 blockage on DS in hippocampal neurons after hypoxia-ischemia were observed. TDCS significantly improved motor function on days 7 and 14 after stroke as indicated by reduced BWT scores compared with the MCAO group. The density of DS was decreased after stroke; the TDCS group had increased DS density compared with the MCAO group on days 3, 7, and 14 (all P<0.0001). Cerebral infarction induced increased PX1 mRNA expression on days 3, 7, and 14 (P<0.0001), and the peak PX1 mRNA expression was observed on day 7. TDCS did not decrease the up-regulated PX1 mRNA expression after stroke on day 3, but did reduce the increased post-stroke PX1 mRNA expression on days 7 and 14 (P<0.0001). TDCS increased the DS density after stroke, indicating that it may promote neural plasticity after stroke. TDCS intervention from day 7 to day 14 after stroke demonstrated motor function improvement and can down-regulate the elevated PX1 mRNA expression after stroke. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Epidermal Growth Factor-like Domain 7 Predicts Response to First-Line Chemotherapy and Bevacizumab in Patients with Metastatic Colorectal Cancer

DEFF Research Database (Denmark)

Hansen, Torben Frøstrup; Nielsen, Boye Schnack; Sørensen, Flemming Brandt

2014-01-01

The number of approved antiangiogenic drugs is constantly growing and emphasizes the need for predictive biomarkers. The aim of this study was to analyze the predictive value of epidermal growth factor-like domain 7 (EGFL7) and microRNA-126 (miR126) to first-line chemotherapy combined with bevaci...

Inter-domain Synergism Is Required for Efficient Feeding of Cellulose Chain into Active Site of Cellobiohydrolase Cel7A*

OpenAIRE

Kont, Riin; Kari, Jeppe; Borch, Kim; Westh, Peter; Väljamäe, Priit

2016-01-01

Structural polysaccharides like cellulose and chitin are abundant and their enzymatic degradation to soluble sugars is an important route in green chemistry. Processive glycoside hydrolases (GHs), like cellobiohydrolase Cel7A of Trichoderma reesei (TrCel7A) are key components of efficient enzyme systems. TrCel7A consists of a catalytic domain (CD) and a smaller carbohydrate-binding module (CBM) connected through the glycosylated linker peptide. A tunnel-shaped active site rests in the CD and ...

Crystallization and preliminary crystallographic analysis of an Escherichia coli-selected mutant of the nuclease domain of the metallonuclease colicin E7

International Nuclear Information System (INIS)

Czene, Anikó; Tóth, Eszter; Gyurcsik, Béla; Otten, Harm; Poulsen, Jens-Christian N.; Lo Leggio, Leila; Larsen, Sine; Christensen, Hans E. M.; Nagata, Kyosuke

2013-01-01

An N-terminally truncated mutant of the colicin E7 nuclease domain was crystallized and diffraction data set was collected to 1.6 Å resolution. The metallonuclease colicin E7 is a member of the HNH family of endonucleases. It serves as a bacterial toxin in Escherichia coli, protecting the host cell from other related bacteria and bacteriophages by degradation of their chromosomal DNA under environmental stress. Its cell-killing activity is attributed to the nonspecific nuclease domain (NColE7), which possesses the catalytic ββα-type metal ion-binding HNH motif at its C-terminus. Mutations affecting the positively charged amino acids at the N-terminus of NColE7 (444–576) surprisingly showed no or significantly reduced endonuclease activity [Czene et al. (2013 ▶), J. Biol. Inorg. Chem.18, 309–321]. The necessity of the N-terminal amino acids for the function of the C-terminal catalytic centre poses the possibility of allosteric activation within the enzyme. Precise knowledge of the intramolecular interactions of these residues that affect the catalytic activity could turn NColE7 into a novel platform for artificial nuclease design. In this study, the N-terminal deletion mutant ΔN4-NColE7-C* of the nuclease domain of colicin E7 selected by E. coli was overexpressed and crystallized at room temperature by the sitting-drop vapour-diffusion method. X-ray diffraction data were collected to 1.6 Å resolution and could be indexed and averaged in the trigonal space group P3 1 21 or P3 2 21, with unit-cell parameters a = b = 55.4, c = 73.1 Å. Structure determination by molecular replacement is in progress

Piroxicam, a traditional non-steroidal anti-inflammatory drug (NSAID) causes apoptosis by ROS mediated Akt activation.

Science.gov (United States)

Rai, Neha; Sarkar, Munna; Raha, Sanghamitra

2015-12-01

Piroxicam (Px) belongs to the oxicam group of the non-steroidal anti-inflammatory drugs (NSAIDs) and have been shown to exert chemopreventive and chemotherapeutic effects in animal models and cultured animal cells. However, little is known about the mode of action of Px and its cellular targets. We explored the role of Px, in triggering apoptosis and examined the involvement of upstream cellular mechanisms in apoptosis induction by Px. Our studies with human breast cancer cells MCF-7 show that Px induces reactive oxygen species (ROS) generation along with apoptotic cell death. ROS release lead to Akt activation. On evaluation it became evident that ROS mediated apoptosis induction was due to Akt activation (hyper phosphorylation). Silencing the expression of Akt using siRNA and a specific Akt inhibitor, triciribine further confirmed the findings. However Px failed to cause ROS generation, cell death or Akt phosphorylation in another human breast cancer cells MDA-MB-231 which is estrogen receptor negative and more aggressive compared to MCF-7 cells. This suggests that Px has cell type specific effects. Thus we revealed for the first time that Px can induce apoptosis by ROS mediated Akt hyperphosphorylation/activation. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Management and communication courses – Places available

CERN Multimedia

2014-01-01

Please note that there are some places available on the following management and communication courses starting in September or October.   For more information on the course, click on the course title, which will take you to the training catalogue. You can then sign up on line.  .tftable {color:#333333;width:100%;border-width: 1px;border-color: #a9a9a9;border-collapse: collapse;} .tftable th {background-color:#cdcdcd;border-width: 1px;padding: 8px;border-style: solid;border-color: #a9a9a9;text-align:left;} .tftable tr {background-color:#ffffff;} .tftable td {border-width: 1px;padding: 8px;border-style: solid;border-color: #a9a9a9;} Course Next session Duration Language Availability Managing Time 15 September 9 October 7 November 20 hours English 2 Managing Stress 6 October 7 October 16 hours English 5  

DNA repair characteristics of a hybrid cell clone between xeroderma pigmentosum and Potorous tridactilis

International Nuclear Information System (INIS)

Ida, Kenji

1986-01-01

A hybrid cell clone PX1 was isolated by fusing UV sensitive XP20S(SV)neo, an SV-40-transformed, neomycin-resistant xeroderma pigmentosum (XP) cell line, and Pt K2, a rat kangaroo (Potorous tridactilis) cell line. The UV-survival curve of PX1 cells fell midway between those of Pt K2 and XP20S(SV)neo cells, since mean lethal doses(D 0 ) were 2.5, 4.7 and 0.27 J/m 2 for PX1, Pt K2 and XP20S(SV)neo, respectively. Amounts of unscheduled DNA synthesis (UDS) after UV, relative to normal human cells, were 60.4 % for Pt K2, 37.7 % for PX1 and 0.1 % for XP20S(SV)neo. Such relative UDS capacities for excision repair of Pt K2, PX1 and XP20S(SV)neo were also consistent with the respective relative capacities of host cell reactivation (HCR) of UV-irradiated Herpes simplex virus. Apparently, there was no single Pt K2 chromosome in the PX1 cells. One possibility is that a gene which may account for the partial restoration of the UV resistance has been transferred from Pt K2 to PX1. (author)

A field study using the fungicide benomyl to investigate the effect of mycorrhizal fungi on plant fitness.

Science.gov (United States)

Carey, Peter D; Fitter, Alastair H; Watkinson, Andrew R

1992-07-01

The effect of vesicular-arbuscular mycorrhiza (VAM) on the fecundity ofVulpia ciliata ssp.ambigua was investigated at two field sites in eastern England by applying the fungicide benomyl to reduce VAM infection. The application of benomyl at the two sites produced very different results. At one site the application of the fungicide reduced the fecundity of plants whereas at the other fecundity was increased. At the first site the reduction in fecundity was linked to a significant reduction in VAM infection on the sprayed plants. The mechanism of the benefit associated with the VAM infection is however unclear: there was no treatment effect on morphology or on phosphorus inflow. At the second site, where fecundity was increased, there was only a negligible amount of VAM infection amongst the unsprayed plants and it is suggested that the increase in fecundity with the application of benomyl may have resulted from a reduction in infection by other, presumably pathogenic, fungi. The value of VAM fungi to the host plant may therefore not be restricted to physiological benefits. They may also provide protection to the plant by competing for space with other species of pathogenic fungi.

The C-terminal domain of the Arabidopsis AtMBD7 protein confers strong chromatin binding activity

International Nuclear Information System (INIS)

Zemach, Assaf; Paul, Laju K.; Stambolsky, Perry; Efroni, Idan; Rotter, Varda; Grafi, Gideon

2009-01-01

The Arabidopsis MBD7 (AtMBD7) - a naturally occurring poly MBD protein - was previously found to be functional in binding methylated-CpG dinucleotides in vitro and localized to highly methylated chromocenters in vivo. Furthermore, AtMBD7 has significantly lower mobility within the nucleus conferred by cooperative activity of its three MBD motifs. Here we show that besides the MBD motifs, AtMBD7 possesses a strong chromatin binding domain located at its C-terminus designated sticky-C (StkC). Mutational analysis showed that a glutamic acid residue near the C-terminus is essential though not sufficient for the StkC function. Further analysis demonstrated that this motif can render nuclear proteins highly immobile both in plant and animal cells, without affecting their native subnuclear localization. Thus, the C-terminal, StkC motif plays an important role in fastening AtMBD7 to its chromosomal, CpG-methylated sites. It may be possible to utilize this motif for fastening nuclear proteins to their chromosomal sites both in plant and animal cells for research and gene therapy applications.

Pertumbuhan Cabai Merah (Capsicum annuum L. pada Tanah Masam yang Diinokulasi Mikoriza Vesikula Arbuskula (MVA Campuran dan Pupuk Fosfat

Directory of Open Access Journals (Sweden)

Maryam Jamilah

2017-06-01

Full Text Available This research aimed to find out the interaction effect between mixed Vesicular Arbuscular Mycorrhiza (VAM and phosphate fertilizer to the growth of red chili (C. annuum in acid soil, and to fnd out the best combination of mixed VAM and phosphate fertilizer to the growth of red chili (C. annuum in acid soil. This research used an experimental method with Completely Randomized Design (CRD in a factorial pattern with two factors. The first factor was mixed VAM dosages consisted of four levels: 0; 10; 15; 20 g/plant. The second factor was phosphate fertilizer dosages consisted of four levels:  0; 0,2; 0,4; 0,6 g/plant. Each combination treatment had three replication. The parameters were observed in the form of plant height, stem diameter, plant top dry weight, degree of VAM infection, and P content of plant tissue. Data obtained from the observation was analyzed with Analysis of Variance (ANOVA at an error rate of 5% and 1%, treatment that showed significant or very significant result, then followed with Honestly Significant Difference (HSD test. The result showed that interaction between mixed Vesicular Arbuscular Mycorrhiza (VAM and phosphate fertilizer did not increase the plant height, stem diameter, and plant top dry weight, but each factor increased the plant height, stem diameter, and plant top dry weight. VAM dosage inoculation of 20 g/plant without phosphate fertilizer is the most effective combination in increasing the degree of VAM infection.

Revegetation of oil sands tailings. Growth improvement of silver-berry and buffalo-berry by inoculation with mycorrhizal fungi and N/sub 2/-fixing bacteria

Energy Technology Data Exchange (ETDEWEB)

Visser, S.; Danielson, R.M.

1988-01-01

The ability of actinorhizal shrubs to tolerate inhospitable conditions while improving soil fertility and organic matter status has led to increased usage of these plants for land reclamation and amenity planting purposes. Silver-berry and buffalo-berry are two such shrubs being tested as potential candidates for the revegetation of the oil sands tailings in northeastern Alberta. Associated with the roots of silver-berry and buffalo-berry are two symbiants, the N/sub 2/-fixing actimomycete Frankia and the vesicular-arbuscular mycorrhizal (VAM) fungi. Numerous studies have demonstrated that, particularly in nutrient-limited conditions, mycorrhization and nodulation can result in significantly better plant performance as a consequence of improved N and P nutrition. It was found in this study that in Alberta, silver-berry and buffalo-berry are strictly VA mycorrhizal; that they are highly dependent on their symbiants for optimum growth; and that the VAM inoculum potential of both stockpiled and undisturbed muskeg peak is negligible, due to the absence of VAM hosts. Means to increase the inoculum potential of peat have been studied. The efficacy of inoculating seedlings grown in greenhouses with VAM and Frankia has been demonstrated. Overwinter mortality was higher for inoculated shrubs, but after one growing season, shoot-weights of silver-berry were 3 to 7 times greater than for uninoculated shrubs, and shoot weights of buffalo-berry were 3 to 5 times greater. 122 refs., 12 figs., 31 tabs.

CERN Bulletin publication schedule for 2015

CERN Multimedia

2014-01-01

The table below lists the 2015 publication dates for the CERN Bulletin and the corresponding deadlines for the submission of announcements. Please note that all announcements must be submitted by 12 noon on Tuesdays at the latest.   .tftable {font-size:12px;color:#333333;width:100%;border-width: 1px;border-color: #a9a9a9;border-collapse: collapse;} .tftable th {font-size:12px;background-color:#b8b8b8;border-width: 1px;padding: 8px;border-style: solid;border-color: #a9a9a9;text-align:left;} .tftable tr {background-color:#ffffff;} .tftable td {font-size:12px;border-width: 1px;padding: 8px;border-style: solid;border-color: #a9a9a9;} .tftable tr:hover {background-color:#ffff99;} Bulletin No. (corresponding to the week number) Submission deadline for announcements (before 12 noon) Publication of Bulletin (web version) 4-5 Tuesday 13 January Friday 16 January 6-7 Tuesday 26 January Friday 30 January 8-9 Tuesday 10 February Friday 13 February 10-11 Tuesday 24 February ...

Different Effects of Bacillus thuringiensis Toxin Cry1Ab on Midgut Cell Transmembrane Potential of Mythimna separata and Agrotis ipsilon Larvae

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Yingying Wang

2015-12-01

Full Text Available Bacillus thuringiensis (Bt Cry toxins from the Cry1A family demonstrate significantly different toxicities against members of the family Noctuidae for unknown reasons. In this study, membrane potential was measured and analyzed in freshly isolated midgut samples from Mythimna separata and Agrotis ipsilon larvae under oral administration and in vitro incubation with Bt toxin Cry1Ab to elucidate the mechanism of action for further control of these pests. Bioassay results showed that the larvae of M. separata achieved a LD50 of 258.84 ng/larva at 24 h after ingestion; M. separata larvae were at least eightfold more sensitive than A. ipsilon larvae to Cry1Ab. Force-feeding showed that the observed midgut apical-membrane potential (Vam of M. separata larvae was significantly depolarized from −82.9 ± 6.6 mV to −19.9 ± 7.2 mV at 8 h after ingestion of 1 μg activated Cry1Ab, whereas no obvious changes were detected in A. ipsilon larvae with dosage of 5 μg Cry1Ab. The activated Cry1Ab caused a distinct concentration-dependent depolarization of the apical membrane; Vam was reduced by 50% after 14.7 ± 0.2, 9.8 ± 0.4, and 7.6 ± 0.6 min of treatment with 1, 5, and 10 μg/mL Cry1Ab, respectively. Cry1Ab showed a minimal effect on A. ipsilon larvae even at 20 μg/mL, and Vam decreased by 26.3% ± 2.3% after 15 min. The concentrations of Cry1Ab displayed no significant effect on the basolateral side of the epithelium. The Vam of A. ipsilon (−33.19 ± 6.29 mV, n = 51 was only half that of M. separata (−80.94 ± 6.95 mV, n = 75. The different degrees of sensitivity to Cry1Ab were speculatively associated with various habits, as well as the diverse physiological or biochemical characteristics of the midgut cell membranes.

Crystal structure of the Ig1 domain of the neural cell adhesion molecule NCAM2 displays domain swapping

DEFF Research Database (Denmark)

Rasmussen, Kim Krighaar; Kulahin, Nikolaj; Kristensen, Ole

2008-01-01

The crystal structure of the first immunoglobulin (Ig1) domain of neural cell adhesion molecule 2 (NCAM2/OCAM/RNCAM) is presented at a resolution of 2.7 A. NCAM2 is a member of the immunoglobulin superfamily of cell adhesion molecules (IgCAMs). In the structure, two Ig domains interact by domain...

Inoculum density of Glomus mosseae and growth of onion plants in unsterilized bituminous coal spoil

Energy Technology Data Exchange (ETDEWEB)

Khan, A.G.

1988-01-01

The effect of inoculum, density (number of vesicular-arbuscular mycorrhizal (VAM) propagules g/sup -1/ of inoculum) on the growth of onions (Allium cepa L.) infected by Glomus mosseae (Nicol and Gerd). Gerdemann and Trappe, Comb nov in unsterilized coal spoil containing indigenous VAM fungi, including G. mosseae, was investigated. The amount of onion roots converted to mycorrhizas by inoculant fungus, estimated by a gridline intersect method, increased with inoculum density (..gamma..0.62, P0.05) until a plateau was reached. Onion growth responses also increased significantly (P<0.05) with the amount of VAM inoculum present in the coal spoil. The initial linear relationship between inoculum propagules (MPN estimates), percent colonization of onion roots and onion shoot dry weight became quadratic as the number of infection propagules increased. VAM infection had no significant effect on root:shoot ratios. Similarly there was no significant interaction (P>0.05) between the inoculum density, VAM-colonized root mass and the onion root:shoot fresh weight ratios. The amount of the windswept bituminous coal spoil bound to VAM (presumably because of VAM external hyphae) also increased as inoculum density increased (..gamma..0.63, P<0.05). There was a stronger correlation (ga0.85, P<0.05) between the amount of spoil adhered per plant and the root fresh wt plant/sup -1/ indicating that root effects were primarily responsible for increasing spoil adherence. There were negative correlations (P<0.05) between root fresh wt plant/sup -1/ (..gamma..-0.68), inoculum density (..gamma..-0.589), percent root elngth infected (..gamma..-0.73) and the amount of spoil adhered g/sup -1/ root fresh wt. The possible exploitation of VAM in revegetation of bituminous coal spoil is discussed. 25 refs., 2 tabs.

Structural analysis of a 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase with an N-terminal chorismate mutase-like regulatory domain

Energy Technology Data Exchange (ETDEWEB)

Light, Samuel H.; Halavaty, Andrei S.; Minasov, George; Shuvalova, Ludmilla; Anderson, Wayne F. (NWU)

2012-06-27

3-Deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS) catalyzes the first step in the biosynthesis of a number of aromatic metabolites. Likely because this reaction is situated at a pivotal biosynthetic gateway, several DAHPS classes distinguished by distinct mechanisms of allosteric regulation have independently evolved. One class of DAHPSs contains a regulatory domain with sequence homology to chorismate mutase - an enzyme further downstream of DAHPS that catalyzes the first committed step in tyrosine/phenylalanine biosynthesis - and is inhibited by chorismate mutase substrate (chorismate) and product (prephenate). Described in this work, structures of the Listeria monocytogenes chorismate/prephenate regulated DAHPS in complex with Mn{sup 2+} and Mn{sup 2+} + phosphoenolpyruvate reveal an unusual quaternary architecture: DAHPS domains assemble as a tetramer, from either side of which chorismate mutase-like (CML) regulatory domains asymmetrically emerge to form a pair of dimers. This domain organization suggests that chorismate/prephenate binding promotes a stable interaction between the discrete regulatory and catalytic domains and supports a mechanism of allosteric inhibition similar to tyrosine/phenylalanine control of a related DAHPS class. We argue that the structural similarity of chorismate mutase enzyme and CML regulatory domain provides a unique opportunity for the design of a multitarget antibacterial.

Simulation of the containment spray system test PACOS PX2.2 with the integral code ASTEC and the containment code system COCOSYS

International Nuclear Information System (INIS)

Risken, Tobias; Koch, Marco K.

2011-01-01

The reactor safety research contains the analysis of postulated accidents in nuclear power plants (npp). These accidents may involve a loss of coolant from the nuclear plant's reactor coolant system, during which heat and pressure within the containment are increased. To handle these atmospheric conditions, containment spray systems are installed in various light water reactors (LWR) worldwide as a part of the accident management system. For the improvement and the safety ensurance in npp operation and accident management, numeric simulations of postulated accident scenarios are performed. The presented calculations regard the predictability of the containment spray system's effect with the integral code ASTEC and the containment code system COCOSYS, performed at Ruhr-Universitaet Bochum. Therefore the test PACOS Px2.2 is simulated, in which water is sprayed in the stratified containment atmosphere of the BMC (Battelle Modell-Containment). (orig.)

A long HBV transcript encoding pX is inefficiently exported from the nucleus

International Nuclear Information System (INIS)

Doitsh, Gilad; Shaul, Yosef

2003-01-01

The longest hepatitis B virus transcript is a 3.9-kb mRNA whose function remained unclear. In this study, we wished to identify the translation products and physiological role of this viral transcript. This transcript initiates from the X promoter region ignoring the inefficient and noncanonical viral polyadenylation signal at the first round of transcription. However, an HBV mutant with canonical polyadenylation signal continues, though with lower efficiency, to program the synthesis of this long transcript, indicating that the deviated HBV polyadenylation signal is important but not essential to enable transcription of the 3.9-kb species. The 3.9-kb RNA contains two times the X open reading frame (ORF). The X ORF at the 5'-end is positioned upstream of the CORE gene. By generating an HBV DNA mutant in which the X and Core ORFs are fused, we demonstrated the production of a 40-kDa X-Core fusion protein that must be encoded by the 3.9-kb transcript. Mutagenesis studies revealed that the production of this protein depends on the 5' X ORF ATG, suggesting that the 3.9-kb RNA is active in translation of the X ORF. Based on these features, the 3.9-kb transcript was designated lxRNA for long X RNA. Unlike other HBV transcripts, lxRNA harbors two copies of PRE, the posttranscriptional regulatory element that controls the nuclear export of HBV mRNAs. Unexpectedly, despite the presence of PRE sequences, RNA fractionation analysis revealed that lxRNA barely accumulates in the cytoplasm, suggesting that nuclear export of lxRNA is poor. Collectively, our data suggest that two distinct HBV mRNA species encode pX and that the HBV transcripts are differentially regulated at the level of nuclear export

Increased Sporulation of Vesicular-Arbuscular Mycorrhizal Fungi by Manipulation of Nutrient Regimens †

OpenAIRE

Douds, David D.; Schenck, N. C.

1990-01-01

Adjustment of pot culture nutrient solutions increased root colonization and sporulation of vesicular-arbuscular mycorrhizal (VAM) fungi. Paspalum notatum Flugge and VAM fungi were grown in a sandy soil low in N and available P. Hoagland nutrient solution without P enhanced sporulation in soil and root colonization of Acaulospora longula, Scutellospora heterogama, Gigaspora margarita, and a wide range of other VAM fungi over levels produced by a tap water control or nutrient solutions contain...

Respons Fisiologi Beberapa Genotipe Kedelai yang Bersimbiosis dengan MVA terhadap Berbagai Tingkat Cekaman Kekeringan

Directory of Open Access Journals (Sweden)

HAPSOH

2006-06-01

Full Text Available Present research was aimed to study physiological changes of soybean which were inoculated with vesicular arbuscular mycorrhizal fungi (VAM. Glomus etunicatum was exposed to moderate and severe drought condition. Symbiotic association with VAM improved adaptability as it was shown by the increasing leaf proline content. The MLG 3474 and Sindoro are the more tolerant genotypes while the responses of plant to VAM on improving the adaptability to drought were larger on Lokon.

A Fast, Efficient Domain Adaptation Technique for Cross-Domain Electroencephalography(EEG-Based Emotion Recognition

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Xin Chai

2017-05-01

achieves values of 77.88% and 7.33% on average, respectively. For the online analysis, the average classification accuracy and standard deviation of ASFM in the subject-to-subject evaluation for all the 15 subjects in a dataset was 75.11% and 7.65%, respectively, gaining a significant performance improvement compared to the best baseline LR which achieves 56.38% and 7.48%, respectively. The experimental results confirm the effectiveness of the proposed method relative to state-of-the-art methods. Moreover, computational efficiency of the proposed ASFM method is much better than standard domain adaptation; if the numbers of training samples and test samples are controlled within certain range, it is suitable for real-time classification. It can be concluded that ASFM is a useful and effective tool for decreasing domain discrepancy and reducing performance degradation across subjects and sessions in the field of EEG-based emotion recognition.

Structural basis of enzymatic activity for the ferulic acid decarboxylase (FADase from Enterobacter sp. Px6-4.

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Wen Gu

Full Text Available Microbial ferulic acid decarboxylase (FADase catalyzes the transformation of ferulic acid to 4-hydroxy-3-methoxystyrene (4-vinylguaiacol via non-oxidative decarboxylation. Here we report the crystal structures of the Enterobacter sp. Px6-4 FADase and the enzyme in complex with substrate analogues. Our analyses revealed that FADase possessed a half-opened bottom β-barrel with the catalytic pocket located between the middle of the core β-barrel and the helical bottom. Its structure shared a high degree of similarity with members of the phenolic acid decarboxylase (PAD superfamily. Structural analysis revealed that FADase catalyzed reactions by an "open-closed" mechanism involving a pocket of 8 × 8 × 15 Å dimension on the surface of the enzyme. The active pocket could directly contact the solvent and allow the substrate to enter when induced by substrate analogues. Site-directed mutagenesis showed that the E134A mutation decreased the enzyme activity by more than 60%, and Y21A and Y27A mutations abolished the enzyme activity completely. The combined structural and mutagenesis results suggest that during decarboxylation of ferulic acid by FADase, Trp25 and Tyr27 are required for the entering and proper orientation of the substrate while Glu134 and Asn23 participate in proton transfer.

The Proteasix Ontology.

Science.gov (United States)

Arguello Casteleiro, Mercedes; Klein, Julie; Stevens, Robert

2016-06-04

The Proteasix Ontology (PxO) is an ontology that supports the Proteasix tool; an open-source peptide-centric tool that can be used to predict automatically and in a large-scale fashion in silico the proteases involved in the generation of proteolytic cleavage fragments (peptides) The PxO re-uses parts of the Protein Ontology, the three Gene Ontology sub-ontologies, the Chemical Entities of Biological Interest Ontology, the Sequence Ontology and bespoke extensions to the PxO in support of a series of roles: 1. To describe the known proteases and their target cleaveage sites. 2. To enable the description of proteolytic cleaveage fragments as the outputs of observed and predicted proteolysis. 3. To use knowledge about the function, species and cellular location of a protease and protein substrate to support the prioritisation of proteases in observed and predicted proteolysis. The PxO is designed to describe the biological underpinnings of the generation of peptides. The peptide-centric PxO seeks to support the Proteasix tool by separating domain knowledge from the operational knowledge used in protease prediction by Proteasix and to support the confirmation of its analyses and results. The Proteasix Ontology may be found at: http://bioportal.bioontology.org/ontologies/PXO . This ontology is free and open for use by everyone.

miRNAs regulated overexpression of ryanodine receptor is involved in chlorantraniliprole resistance in Plutella xylostella (L.)

Science.gov (United States)

Li, Xiuxia; Guo, Lei; Zhou, Xuguo; Gao, Xiwu; Liang, Pei

2015-01-01

The amino acid mutations in ryanodine receptor (RyR) and elevated activity of detoxification enzymes have been associated with the diamide insecticide resistance in the diamondback moth, Plutella xylostella (L.). The up-regulation of P. xylostella RyR mRNA (PxRyR) expression has also been reported in field populations of different graphical origin. However, whether the up-regulation of PxRyR is involved in diamide resistance remains unknown. In this paper, 2.28- to 4.14-fold higher expression of PxRyR was detected in five field collected resistant populations, compared to that in a susceptible population. The expression of PxRyR was up-regulated 5.0- and 7.2-fold, respectively, after P. xylostella was treated with LC50 and LC75 of chlorantraniliprole for 12 h. Suppression of PxRyR using RNA interference restored the toxicity of chlorantraniliprole against the fourth instar larvae from the resistant population. More importantly, the expression of PxRyR is regulated by two miRNAs, miR-7a and miR-8519. These findings provide an empirical evidence of the involvement of miRNAs in the regulation of insecticide resistance, and shed light on the novel targets for the sustainable management of this devastating insect pest. PMID:26370154

Domains within domains and walls within walls: Evidence for polar domains in cryogenic SrTiO.sub.3./sub..

Czech Academy of Sciences Publication Activity Database

Salje, E.K.H.; Aktas, O.; Carpenter, M.A.; Laguta, Valentyn; Scott, J.F.

2013-01-01

Roč. 111, č. 24 (2013), "247603-1"-"247603-5" ISSN 0031-9007 Institutional support: RVO:68378271 Keywords : ferroelectric domains * SrTiO 3 * phase transition Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.728, year: 2013

Seasonality of vesicular-arbuscular mycorrhizae in sedges in a semi-arid tropical grassland

Science.gov (United States)

Muthukumar, T.; Udaiyan, K.

2002-10-01

Vesicular-arbuscular mycorrhizal (VAM) colonization and spore numbers in the rhizosphere of Cyperus iria L. and C. rotundus L., growing in a semi-arid tropical grassland, was studied during the 1993 and 1994 monsoons. In addition, climatic and chemical properties of the soils were determined in order to investigate their influence on mycorrhizal variables. VAM fungal association in the sedges was confirmed by plant- and root-trap culture techniques. The soil nutrients exhibited seasonal variations, but were highly variable between years. Intercellular hyphae and vesicles with occasional intraradical spores characterized mycorrhizal association in sedges. Dark septate fungi also colonized roots of sedges. Temporal variations in mycorrhizal colonization and spore numbers occurred, indicating seasonality. However, the patterns of mycorrhizal colonization and spore numbers were different during both the years. The VAM fungal structures observed were intercellular hyphae and vesicles. Changes in the proportion of root length with VAM structures, total colonization levels and spore numbers were related to climatic and edaphic factors. However, the intensity of influence of climatic and soil factors on VAM tended to vary with sedge species.

Inter-domain Synergism Is Required for Efficient Feeding of Cellulose Chain into Active Site of Cellobiohydrolase Cel7A.

Science.gov (United States)

Kont, Riin; Kari, Jeppe; Borch, Kim; Westh, Peter; Väljamäe, Priit

2016-12-09

Structural polysaccharides like cellulose and chitin are abundant and their enzymatic degradation to soluble sugars is an important route in green chemistry. Processive glycoside hydrolases (GHs), like cellobiohydrolase Cel7A of Trichoderma reesei (TrCel7A) are key components of efficient enzyme systems. TrCel7A consists of a catalytic domain (CD) and a smaller carbohydrate-binding module (CBM) connected through the glycosylated linker peptide. A tunnel-shaped active site rests in the CD and contains 10 glucose unit binding sites. The active site of TrCel7A is lined with four Trp residues with two of them, Trp-40 and Trp-38, in the substrate binding sites near the tunnel entrance. Although addressed in numerous studies the elucidation of the role of CBM and active site aromatics has been obscured by a complex multistep mechanism of processive GHs. Here we studied the role of the CBM-linker and Trp-38 of TrCel7A with respect to binding affinity, on- and off-rates, processivity, and synergism with endoglucanase. The CBM-linker increased the on-rate and substrate affinity of the enzyme. The Trp-38 to Ala substitution resulted in increased off-rates and decreased processivity. The effect of the Trp-38 to Ala substitution on on-rates was strongly dependent on the presence of the CBM-linker. This compensation between CBM-linker and Trp-38 indicates synergism between CBM-linker and CD in feeding the cellulose chain into the active site. The inter-domain synergism was pre-requisite for the efficient degradation of cellulose in the presence of endoglucanase. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Distribution of vesicular-arbuscular mycorrhizal fungi in coal, lignite and calcite mine spoils of India

Energy Technology Data Exchange (ETDEWEB)

Ganesan, V.; Ragupathy, S.; Parthipan, B.; Rani, D.B.R.; Mahadevan, A.

1991-12-31

Vesicular-arbuscular mycorhizzal (VAM) status was assessed for coal, lignite and calcite mine spoils. The three study sites were: The Kothagudem coal field in the south central region where waste materials are piled 1 to 2 m high on the soil surface. Samples were collected from plants growing on the waste. Neyveli, on the southeastern coast, is a lignite coal mine where the spoil is piled 70 to 100 m high on the soil surface. Samples were collected from recently revegetated mine spoil and from 25 year old revegetated sites. The calcite mine at Thazhaiyuthu in the south where the spoil is piled up 2 to 3 m on the soil surface. Samples were collected from 4 to 7 year old reclaimed sites. The wastes generally supported different plant species. The level of VAM infection of plants was markedly different in each mine spoil, with the maximum infection in the coal and calcite spoils, and the least in the lignite spoil. There was more infection in the 25 year old lignite spoil than in the newly revegetated spoil. There were different VAM species in each spoil, and no one species was present in all of the samples. The authors conclude that one of the factors leading to the differences between spoils is the amount of topsoil contained in the spoil (least in the lignite spoils which are very deep). The other is age of the spoils. Unfortunately the authors concluded that the best approach is to enrich the spoils with VAM rather than salvaging and replacing topsoil

Efectos del entrenamiento continuo e interválico de carga externa similar sobre la frecuencia cardiaca Effects of continuous and interval training similar external load on heart rate

Directory of Open Access Journals (Sweden)

J. L. Tuimil

2010-09-01

Full Text Available

Los objetivos de este estudio fueron comparar la frecuencia cardíaca (FC media entre dos tipos de entrenamiento de carga externa equiparada basados en la carrera, la relación de la velocidad aeróbica máxima (VAM con la F.C. de reserva (FCR y los efectos de estos dos tipos de entrenamiento sobre la F.C. basal (FCB. El estudio se llevó a cabo con ocho estudiantes de educación física (23,25 años; VAM: 17,93 Km.h-1 que realizaron dos tipos de entrenamiento: CC =8 km al 70%VAM y CI= 4x(1000m al 90%VAM+1000m al 50% VAM. Se registró la FC durante el entrenamiento y la FCB antes y después del mismo. La diferencia de la FC media entre ambos métodos no fue estadísticamente significativa, sin embargo las medias del CC (FCCC (Z=2,240; p<0,05 y CI (FCCI (Z=2,380; p<0,05 fueron significativamente más elevadas que la calculada al 70% de FCR. La FCB se elevó de forma significativa (Z=2,319; p=0.020 solamente después del entrenamiento CI. En conclusión, dos métodos de entrenamiento distintos, pero de intensidad media similar, pueden dar lugar a una FC media también similar. La intensidad de carrera programada en función de la VAM es significativamente superior a la programada en función de la FCR. El entrenamiento interválico puede tener un mayor efecto sobre el incremento de la FCB.
PALABRAS CLAVE: Frecuencia cardíaca media, frecuencia cardíaca de reserva, frecuencia cardíaca basal, VAM, carrera continua, carrera interválica.

The aims of this study were to compare the mean heart rate response in two training methods of equal average intensity based on running, the relationship of the maximal aerobic speed (VAM with the reserve heart rate (FCR and the effects of these modes of training on the basal heart rate (FCB. The study was carried out with eight physical activity students (23,25 years old; VAM: 17,93 Km.h^-1

Magnetic domain size effect on resistivity and Hall effect of amorphous Fe83-xZr7B10Mx (M=Ni, Nb) alloys

International Nuclear Information System (INIS)

Rhie, K.; Lim, W.Y.; Lee, S.H.; Yu, S.C.

1997-01-01

Studies of effective permeability, core loss and saturation magnetostriction of Fe 83-x Zr 7 B 10 M x (M=Ni, Nb) alloys revealed that the domain width is smallest around x=0.10. We measured the resistivity and low field Hall coefficients of these alloys and found that the maxima of resistivity and Hall coefficients occurred roughly at the same concentrations. Larger surface area of smaller domains is considered the reason. copyright 1997 American Institute of Physics

Domates Pulpu ve Salçasında Viskozite (Konsistens ve Renk Üzerine Proses Koşullarının Etkisi

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Aziz Ekşi

2015-02-01

Full Text Available Kıvam ve renk, domates pulpu ve salçada kaliteyi belirleyen ve ticarette üzerinde en çok durulan iki önemli etkendir. Domates salçasında renk ve kıvam ile hammaddenin durumu arasında yakın bir ilişki bulunduğu bilinmektedir. Ancak her iki kalite öğesini ve özellikle kıvamı, hammadde olduğu kadar, proses koşulları da etkilemektedir.

Pre-analytic evaluation of volumetric absorptive microsampling and integration in a mass spectrometry-based metabolomics workflow.

Science.gov (United States)

Volani, Chiara; Caprioli, Giulia; Calderisi, Giovanni; Sigurdsson, Baldur B; Rainer, Johannes; Gentilini, Ivo; Hicks, Andrew A; Pramstaller, Peter P; Weiss, Guenter; Smarason, Sigurdur V; Paglia, Giuseppe

2017-10-01

Volumetric absorptive microsampling (VAMS) is a novel approach that allows single-drop (10 μL) blood collection. Integration of VAMS with mass spectrometry (MS)-based untargeted metabolomics is an attractive solution for both human and animal studies. However, to boost the use of VAMS in metabolomics, key pre-analytical questions need to be addressed. Therefore, in this work, we integrated VAMS in a MS-based untargeted metabolomics workflow and investigated pre-analytical strategies such as sample extraction procedures and metabolome stability at different storage conditions. We first evaluated the best extraction procedure for the polar metabolome and found that the highest number and amount of metabolites were recovered upon extraction with acetonitrile/water (70:30). In contrast, basic conditions (pH 9) resulted in divergent metabolite profiles mainly resulting from the extraction of intracellular metabolites originating from red blood cells. In addition, the prolonged storage of blood samples at room temperature caused significant changes in metabolome composition, but once the VAMS devices were stored at - 80 °C, the metabolome remained stable for up to 6 months. The time used for drying the sample did also affect the metabolome. In fact, some metabolites were rapidly degraded or accumulated in the sample during the first 48 h at room temperature, indicating that a longer drying step will significantly change the concentration in the sample. Graphical abstract Volumetric absorptive microsampling (VAMS) is a novel technology that allows single-drop blood collection and, in combination with mass spectrometry (MS)-based untargeted metabolomics, represents an attractive solution for both human and animal studies. In this work, we integrated VAMS in a MS-based untargeted metabolomics workflow and investigated pre-analytical strategies such as sample extraction procedures and metabolome stability at different storage conditions. The latter revealed that

Topological domain walls in helimagnets

Science.gov (United States)

Schoenherr, P.; Müller, J.; Köhler, L.; Rosch, A.; Kanazawa, N.; Tokura, Y.; Garst, M.; Meier, D.

2018-05-01

Domain walls naturally arise whenever a symmetry is spontaneously broken. They interconnect regions with different realizations of the broken symmetry, promoting structure formation from cosmological length scales to the atomic level1,2. In ferroelectric and ferromagnetic materials, domain walls with unique functionalities emerge, holding great promise for nanoelectronics and spintronics applications3-5. These walls are usually of Ising, Bloch or Néel type and separate homogeneously ordered domains. Here we demonstrate that a wide variety of new domain walls occurs in the presence of spatially modulated domain states. Using magnetic force microscopy and micromagnetic simulations, we show three fundamental classes of domain walls to arise in the near-room-temperature helimagnet iron germanium. In contrast to conventional ferroics, the domain walls exhibit a well-defined inner structure, which—analogous to cholesteric liquid crystals—consists of topological disclination and dislocation defects. Similar to the magnetic skyrmions that form in the same material6,7, the domain walls can carry a finite topological charge, permitting an efficient coupling to spin currents and contributions to a topological Hall effect. Our study establishes a new family of magnetic nano-objects with non-trivial topology, opening the door to innovative device concepts based on helimagnetic domain walls.

Epidermal growth factor-like domain 7 is a marker of the endothelial lineage and active angiogenesis.

Science.gov (United States)

Bambino, Kathryn; Lacko, Lauretta A; Hajjar, Katherine A; Stuhlmann, Heidi

2014-07-01

Epidermal growth factor-like domain 7 (Egfl7) expression in the developing embryo is largely restricted to sites of mesodermal progenitors of angioblasts/hemangioblasts and the vascular endothelium. We hypothesize that Egfl7 marks the endothelial lineage during embryonic development, and can be used to define the emergence of endothelial progenitor cells, as well as to visualize newly-forming vasculature in the embryo and during the processes of physiologic and pathologic angiogenesis in the adult. We have generated a transgenic mouse strain that expresses enhanced green fluorescent protein (eGFP) under the control of a minimal Egfl7 regulatory sequence (Egfl7:eGFP). Expression of the transgene recapitulated that of endogenous Egfl7 at sites of vasculogenesis and angiogenesis in the allantois, yolk sac, and in the embryo proper. The transgene was not expressed in the quiescent endothelium of most adult organs. However, the uterus and ovary, which undergo vascular growth and remodeling throughout the estrus cycle, expressed high levels of Egfl7:eGFP. Importantly, expression of the Egfl7:eGFP transgene was induced in adult neovasculature. We also found that increased Egfl7 expression contributed to pathologic revascularization in the mouse retina. To our knowledge, this is the first mouse model that enables monitoring of endothelial cells at sites of active vasculogenesis and angiogenesis. This model also facilitated the isolation and characterization of EGFL7(+) endothelial cell populations by fluorescence activated cell sorting (FACS). Together, our results demonstrate that the Egfl7:eGFP reporter mouse is a valuable tool that can be used to elucidate the mechanisms by which blood vessels form during development and under pathologic circumstances. © 2014 Wiley Periodicals, Inc.

Investigation of glutathione peroxidase activity in chicken meat under different experimental conditions

Directory of Open Access Journals (Sweden)

Alexandre José Cichoski

2012-12-01

Full Text Available Due to the fact that previous studies on the enzymatic activity of Glutathione peroxidase (GSH-Px diverge widely in their methodology and results, this study aimed to investigate the influence of different analytical conditions on GSH-Px activity in chicken thighs from broilers that were fed different diets with different sources and concentrations of selenium. GSH-Px activity was evaluated six hours after slaughter and 120 days after frozen storage at -18 ºC. The different analytical conditions included time of pre-incubation (0, 10 and 30 minutes, reaction medium, types of substrate (H2O2 (0.72 mM, 7.2 mM, and 72 mM and Terc-butil hydroperoxide 15 mM, and different buffer concentrations (buffer 1, potassium phosphate 50 mM pH 7.0 + EDTA 1 mM + mercaptoethanol 1 mM, and buffer 2, tris-HCl 50 mM pH 7.6 + EDTA 1 mM + mercapthanol 5 mM. The results show that the highest GSH-Px activity was observed when enzyme and substrate were in contact at 22 ºC without any pre-incubation, and that, when used at concentrations above 0.72 mM, hydrogen peroxide saturated the GSH-Px enzyme and inhibited its activity. The enzyme presented higher affinity to hydrogen peroxide when compared to terc-butil peroxide, and the addition of a buffer containing mercaptoethanol did not increase GSH-Px enzymatic activity. The activity of GSH-Px was not influenced by the source and concentration of selenium in the diet either. The obtained results allowed the determination of the best temperature of contact between the enzyme and substrate (22 ºC, the optimum concentration, and the type of substrate and buffer to be used. This information is extremely useful for future studies on GSH-Px activity in meat due to the divergence and little information found in the literature.

Deletion of the calmodulin-binding domain of Grb7 impairs cell attachment to the extracellular matrix and migration

Energy Technology Data Exchange (ETDEWEB)

García-Palmero, Irene; Villalobo, Antonio, E-mail: antonio.villalobo@iib.uam.es

2013-06-28

Highlights: •Grb7 is a calmodulin (CaM)-binding protein. •Deleting the CaM-binding site impairs cell attachment and migration. •CaM antagonists inhibit Grb7-mediated cell migration. •We conclude that CaM controls Grb7-mediated cell migration. -- Abstract: The adaptor Grb7 is a calmodulin (CaM)-binding protein that participates in signaling pathways involved in cell migration, proliferation and the control of angiogenesis, and plays a significant role in tumor growth, its metastatic spread and tumor-associated neo-vasculature formation. In this report we show that deletion of the CaM-binding site of Grb7, located in the proximal region of its pleckstrin homology (PH) domain, impairs cell migration, cell attachment to the extracellular matrix, and the reorganization of the actin cytoskeleton occurring during this process. Moreover, we show that the cell-permeable CaM antagonists N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) and N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide (W-13) both retard the migration of cells expressing wild type Grb7, but not the migration of cells expressing the mutant protein lacking the CaM-binding site (Grb7Δ), underscoring the proactive role of CaM binding to Grb7 during this process.

Transmission electron and optical microscopy of the domain structure of Ni3B7O13Br ferroic boracite

International Nuclear Information System (INIS)

Castellanos-Guzman, A.G.; Trujillo-Torrez, M.; Czank, M.

2005-01-01

The study investigated the domain structure of nickel bromine boracite single crystals, by means of polarised-light in conjunction with transmission electron microscopy. Single crystals of Ni 3 B 7 O 13 Br were grown by chemical transport reactions in closed quartz ampoules, in the temperature range of 1130 K and were examined by polarising optical microscopy (PLM), and transmission electron microscopy (TEM). PLM was also used in order to study the behaviour of birefringence as a function of temperature. For TEM the single crystals were crushed and mounted on holey carbon films. Comparative electron microscope images were useful for revealing the domain structure of this fully ferroelectric/fully ferroelastic material previously observed between the crossed polars of an optical microscope. X-ray diffraction analysis of the crystal under study was performed at room temperature

Quantitative assessment of caffeine partial clearances in man.

Science.gov (United States)

Lelo, A; Miners, J O; Robson, R A; Birkett, D J

1986-01-01

Five subjects who participated in an earlier study (Lelo et al., 1986b) of the comparative pharmacokinetics of caffeine (CA) and its primary monodemethylated metabolites paraxanthine (PX), theobromine (TB) and theophylline (TP) were administered CA to steady-state. Using areas under the plasma concentration-time curves for each of the dimethylxanthines derived from CA in the steady-state study and individual plasma clearances of PX, TB and TP determined in the previous study, the fractional conversion of CA to PX, TB and TP and the individual partial clearances of CA have been defined. The mean (+/- s.d.) fractional conversion of CA to PX, TB and TP was 79.6 +/- 21.0%, 10.8 +/- 2.4% and 3.7 +/- 1.3%, respectively. When only demethylation pathways are considered PX, TB and TP accounted for 83.9 +/- 5.4%, 12.1 +/- 4.1% and 4.0 +/- 1.4%, respectively of the CA demethylations. The mean partial clearance of CA to PX was approximately 8-fold and 23-fold greater than those to TB and TP respectively. These data confirm earlier reports that PX is the major metabolite of CA in humans but suggest that PX formation is quantitatively more important than previously believed. PMID:3756066

Investigation of glutathione peroxidase activity in chicken meat under different experimental conditions Investigação da atividade de glutationa peroxidase em carne de frango submetida a diferentes condições experimentais

Directory of Open Access Journals (Sweden)

Alexandre José Cichoski

2012-12-01

Full Text Available Due to the fact that previous studies on the enzymatic activity of Glutathione peroxidase (GSH-Px diverge widely in their methodology and results, this study aimed to investigate the influence of different analytical conditions on GSH-Px activity in chicken thighs from broilers that were fed different diets with different sources and concentrations of selenium. GSH-Px activity was evaluated six hours after slaughter and 120 days after frozen storage at -18 ºC. The different analytical conditions included time of pre-incubation (0, 10 and 30 minutes, reaction medium, types of substrate (H2O2 (0.72 mM, 7.2 mM, and 72 mM and Terc-butil hydroperoxide 15 mM, and different buffer concentrations (buffer 1, potassium phosphate 50 mM pH 7.0 + EDTA 1 mM + mercaptoethanol 1 mM, and buffer 2, tris-HCl 50 mM pH 7.6 + EDTA 1 mM + mercapthanol 5 mM. The results show that the highest GSH-Px activity was observed when enzyme and substrate were in contact at 22 ºC without any pre-incubation, and that, when used at concentrations above 0.72 mM, hydrogen peroxide saturated the GSH-Px enzyme and inhibited its activity. The enzyme presented higher affinity to hydrogen peroxide when compared to terc-butil peroxide, and the addition of a buffer containing mercaptoethanol did not increase GSH-Px enzymatic activity. The activity of GSH-Px was not influenced by the source and concentration of selenium in the diet either. The obtained results allowed the determination of the best temperature of contact between the enzyme and substrate (22 ºC, the optimum concentration, and the type of substrate and buffer to be used. This information is extremely useful for future studies on GSH-Px activity in meat due to the divergence and little information found in the literature.Uma vez que estudos anteriores sobre a atividade enzimática da glutationa peroxidase (GSH-Px divergem acerca da metodologia e dos resultados, este estudo teve por objetivo investigar a influência de

Capturing energy from ventilation air methane a preliminary design for a new approach

International Nuclear Information System (INIS)

Cluff, D.L.; Kennedy, G.A.; Bennett, J.G.; Foster, P.J.

2015-01-01

Methane is a potent greenhouse gas (GHG), discharged to the atmosphere by coalmining, the natural gas industry and natural biological processes, second only to carbon dioxide; thus, any reduction in atmospheric methane would be globally beneficial. The capture or use of ventilation air methane (VAM) is challenging because it is a high volume low concentration methane source. This results in the routine discharge of methane into the atmosphere. A review of VAM mitigation technologies is provided and the main disadvantages of the existing technologies are discussed. In the proposed VamTurBurner © system, the heat from the combustion chamber is transferred to the preheating zone either by a heat exchanger or by redirecting the combustion products to mix with the ventilation air stream from a coalmine. Gas turbines (GT) are used to produce electricity with the exhaust gases directed to mix with the incoming ventilation airflow. The turbulence introduced by the GT exhaust assists with mixing of the incoming ventilation airflow and the return flow of combustion products from the combustion chamber. The combustion products are a source of heat, which increases the temperature of the incoming ventilation air to a value high enough for the methane to undergo flameless combustion upon encountering the igniters. The high temperature combustion products enter a multi-generation system. The multi-generation system is based on mature engineering technology such as heat exchangers and steam turbines. The residual heat provides additional heat based products such as industrial scale drying, chilling by an absorption chiller or simply hot water. The VamTurBurner © uses the energy from the GT, igniters and VAM to provide clean efficient energy while mitigating the atmospheric emissions of methane. The opportunity to collect carbon credits may improve the economics. Since the VAM is a free energy source, the output of the system is greater than the purchased energy. - Highlights: �

Influence of Vesicular-Arbuscular Mycorrhizal Fungi on the Response of Potato to Phosphorus Deficiency.

Science.gov (United States)

McArthur, DAJ.; Knowles, N. R.

1993-01-01

Morphological and biochemical interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus (Glomus fasciculatum [Thaxt. sensu Gerdemann] Gerdemann and Trappe) and potato (Solanum tuberosum L.) plants during the development of P deficiency were characterized. Nonmycorrhizal (NM) plants grown for 63 d with low abiotic P supply (0.5 mM) produced 34, 52, and 73% less root, shoot, and tuber dry matter, respectively, than plants grown with high P (2.5 mM). The total leaf area and the leaf area:plant dry weight ratio of low-P plants were substantially lower than those of high-P plants. Moreover, a lower shoot:root dry weight ratio and tuber:plant dry weight ratio in low-P plants than in high-P plants characterized a major effect of P deficiency stress on dry matter partitioning. In addition to a slower rate of growth, low-P plants accumulated nonreducing sugars and nitrate. Furthermore, root respiration and leaf nitrate reductase activity were lower in low-P plants than in high-P plants. Low abiotic P supply also induced physiological changes that contributed to the greater efficiency of P acquisition by low-P plants than by high-P plants. For example, allocation of dry matter and P to root growth was less restricted by P deficiency stress than to shoot and tuber growth. Also, the specific activities of root acid phosphatases and vanadate-sensitive microsomal ATPases were enhanced in P-deficient plants. The establishment of a VAM symbiosis by low-P plants was essential for efficient P acquisition, and a greater root infection level for P-stressed plants indicated increased compatibility to the VAM fungus. By 63 d after planting, low-P VAM plants had recovered 42% more of the available soil P than low-P NM plants. However, the VAM fungus only partially alleviated P deficiency stress and did not completely compensate for inadequate abiotic P supply. Although the specific activities of acid phosphatases and microsomal ATPases were only marginally influenced by VAM

Conditional Random Fields for Pattern Recognition Applied to Structured Data

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Tom Burr

2015-07-01

Full Text Available Pattern recognition uses measurements from an input domain, X, to predict their labels from an output domain, Y. Image analysis is one setting where one might want to infer whether a pixel patch contains an object that is “manmade” (such as a building or “natural” (such as a tree. Suppose the label for a pixel patch is “manmade”; if the label for a nearby pixel patch is then more likely to be “manmade” there is structure in the output domain that can be exploited to improve pattern recognition performance. Modeling P(X is difficult because features between parts of the model are often correlated. Therefore, conditional random fields (CRFs model structured data using the conditional distribution P(Y|X = x, without specifying a model for P(X, and are well suited for applications with dependent features. This paper has two parts. First, we overview CRFs and their application to pattern recognition in structured problems. Our primary examples are image analysis applications in which there is dependence among samples (pixel patches in the output domain. Second, we identify research topics and present numerical examples.

Influence of arbuscular mycorrhizal fungi, rhizobium inoculation and rock phosphate on growth and quality of lentil

International Nuclear Information System (INIS)

Yaseen, T.; Ali, K.

2016-01-01

Effective inoculation of legumes has the ability not only to ensure nutrients availability to plants particularly in N and P-limiting (due to improvement in nutrients fixation) environments but also can manipulate the environmental hazards associated with over inorganic fertilization. To support this view, the current experiment was conducted to study the influence of rock phosphorus fertilization, Arbuscular Mycorrhizae (AM) and Rhizobium inoculation on growth and yield parameters of Lens culinaris (NARC.2008-4). In addition, the current experiments aimed to evaluate the effect of different inoculation practices on crop quality in comparison with control (no inoculation).The experiment was laid out in randomized complete block design with four replications during winter (2010-11 and 2012-13) at the Department of Botany University of Peshawar Pakistan. Overall, inoculated plant performed superior in terms of plant growth and quality over control. All plants measured parameters (Leaf chlorophyll content, seed protein, fiber and ash content, plant height, number of seed pod-1, leaves plant-1, flowers plant-1, pods plant-1, pod length and thousand seed weight) were highest in plant samples inoculated with VAM and Rhizobium in combination as compared to sole application of VAM or Rhizobium. Combined inoculation of VAM and Rhizobium caused 10, 24, 17, 21 and 14% increase in seed protein content, leaf chlorophyll content, seed fiber content, seed ash content and number of seed pod-1 over sole application of VAM and Rhizobium when averaged over two years. Combined application of Rhizobium + VAM enhanced seed yield plant-1 by 45% over control and 24% and 28% over sole inoculation of VAM and Rhizobium respectively. It is therefore concluded that dual inoculation of VAM + Rhizobium and rock phosphate may be of only limited consequence in high input agricultural systems. (author)

Ammonia Assimilation in Zea mays L. Infected with a Vesicular-Arbuscular Mycorrhizal Fungus Glomus fasciculatum.

Science.gov (United States)

Cliquet, J. B.; Stewart, G. R.

1993-03-01

To investigate nitrogen assimilation and translocation in Zea mays L. colonized by the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus fasciculatum (Thax. sensu Gerd.), we measured key enzyme activities, 15N incorporation into free amino acids, and 15N translocation from roots to shoots. Glutamine synthetase and nitrate reductase activities were increased in both roots and shoots compared with control plants, and glutamate dehydrogenase activity increased in roots only. In the presence of [15N]ammonium, glutamine amide was the most heavily labeled product. More label was incorporated into amino acids in VAM plants. The kinetics of 15N labeling and effects of methionine sulfoximine on distribution of 15N-labeled products were entirely consistent with the operation of the glutamate synthase cycle. No evidence was found for ammonium assimilation via glutamate dehydrogenase. 15N translocation from roots to shoots through the xylem was higher in VAM plants compared with control plants. These results establish that, in maize, VAM fungi increase ammonium assimilation, glutamine production, and xylem nitrogen translocation. Unlike some ectomycorrhizal fungi, VAM fungi do not appear to alter the pathway of ammonium assimilation in roots of their hosts.

Populasi jamur mikoriza vesikular-arbuskular pada lahan bekas galian emas yang direklamasi dengan legum tumbuh cepat dikombinasikan dengan penutup tanah dan mikroba

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Suciatmih Suciatmih

2012-02-01

Full Text Available field work has been carried out to study the population of vesicular-arbuscular mycorrhizal (VAM fungi on degraded gold mining land that was reclamated with fast growing legume (Enterolobium sp. and Acacia mangium trees in combination with cover crops (Centrosema pubescen dan Flemingia congesta and microbe (VAM fungi, Rhizobium sp. and mixed Rhizobium sp. and phosphate solubilizing bacteria inoculation. Reclamation with fast growing legumes in combination with cover crops and microbe inoculation on the degraded land increased the population of VAM fungi. After 1.5 years, the population of the fungi on the reclamated land increased from 3.4 (control to 6.1–80.5 spore/g soil. The highest spore population resulted by combination between Acacia mangium, C. pubescen, and VAM fungi (V2I1C1 plot followed by combination between Acacia mangium without cover crop, and VAM fungi inoculation (V2I1C0 plot and combination between Enterolobium sp. without cover crop and mixed Rhizobium and phosphate solubilizing bacteria inoculation (V1I3Co plot were 80.5, 56.0 and 51.8 respectively.

Characterization of the Vectron PX-570 Crystal Oscillator for Use in Harsh Environments

Science.gov (United States)

Li, Jacob; Patterson, Richard L.; Hammoud, Ahmad

2012-01-01

Computing hardware, data-acquisition systems, communications systems, and many electronic control systems require well-controlled timing signals for proper and accurate operation. These signals are, in most cases, provided by circuits that employ crystal oscillators due to availability, cost, ease of operation, and accuracy. In some cases, the electronic systems are expected to survive and operate under harsh conditions that include exposure to extreme temperatures. These applications exist in terrestrial systems as well as in aerospace products. Well-logging, geothermal systems, and industrial process control are examples of ground-based applications, while distributed jet engine control in aircraft, space-based observatories (such as the James Webb Space Telescope), satellites, and lunar and planetary landers are typical environments where electronics are exposed to harsh operating conditions. To ensure these devices produce reliable results, the digital heartbeat from the oscillator must deliver a stable signal that is not affected by external temperature or other conditions. One such solution is a recently introduced commercial-off-the-shelf (COTS) oscillator, the PX-570 series from Vectron International. The oscillator was designed for high-temperature applications and as proof, the crystal oscillator was subjected to a wide suite of tests to determine its ruggedness for operation in harsh environments. The tests performed by Vectron included electrical characterization under wide range of temperature, accelerated life test/aging, shock and vibration, internal moisture analysis, ESD threshold, and latch-up testing. The parametric evaluation was performed on the oscillator's frequency, output signal rise and fall times, duty cycle, and supply current over the temperature range of -125 C to +230 C. The evaluations also determined the effects of thermal cycling and the oscillator's re-start capability at extreme hot and cold temperatures. These thermal cycling

Crystal structures of wild-type Trichoderma reesei Cel7A catalytic domain in open and closed states

Energy Technology Data Exchange (ETDEWEB)

Bodenheimer, Annette M. [Molecular and Structural Biochemistry Department, North Carolina State University, Raleigh NC USA; Neutron Sciences Directorate, Oak Ridge National Laboratory, TN USA; Meilleur, Flora [Molecular and Structural Biochemistry Department, North Carolina State University, Raleigh NC USA; Neutron Sciences Directorate, Oak Ridge National Laboratory, TN USA

2016-11-07

Trichoderma reesei Cel7A efficiently hydrolyses cellulose. We report here the crystallographic structures of the wild-type TrCel7A catalytic domain (CD) in an open state and, for the first time, in a closed state. Molecular dynamics (MD) simulations indicate that the loops along the CD tunnel move in concerted motions. Together, the crystallographic and MD data suggest that the CD cycles between the tense and relaxed forms that are characteristic of work producing enzymes. Analysis of the interactions formed by R251 provides a structural rationale for the concurrent decrease in product inhibition and catalytic efficiency measured for product-binding site mutants.

Restoration of fly ash dump through biological interventions.

Science.gov (United States)

Juwarkar, Asha A; Jambhulkar, Hemlata P

2008-04-01

Field experiment on 10 ha area of fly ash dump was conducted to restore and revegetate it using biological interventions, which involves use of organic amendment, selection of suitable plant species along with specialized nitrogen fixing strains of biofertilizer. The results of the study indicated that amendment with farm yard manure at 50 t/ha improved the physical properties of fly ash such as maximum water holding capacity from 40.0 to 62.42% while porosity improved from 56.78 to 58.45%. The nitrogen content was increased by 4.5 times due to addition of nitrogen fixing strains of Bradyrhizobium and Azotobacter species, while phosphate content was increased by 10.0 times due to addition of VAM, which helps in phosphate immobilization. Due to biofertilizer inoculation different microbial groups such as Rhizobium, Azotobacter and VAM spores, which were practically absent in fly ash improved to 7.1 x 10(7), 9.2 x 10(7) CFU/g and 35 VAM spores/10 g of fly ash, respectively. Inoculation of biofertilizer and application of FYM helped in reducing the toxicity of heavy metals such as cadmium, copper, nickel and lead which were reduced by 25, 46, 48 and 47%, respectively, due to the increased organic matter content in the fly ash which complexes the heavy metals thereby decreasing the toxicity of metals. Amendment of fly ash with FYM and biofertilizer helped in profuse root development showing 15 times higher growth in Dendrocalamus strictus plant as compared to the control. Thus amendment and biofertilizer application provided better supportive material for anchorage and growth of the plant.

Vesicular arbuscular mycorrhizal fungi prevalence and diversity in ...

African Journals Online (AJOL)

The prevalence and population levels of VAM fungi in a range of field soil environments in Zimbabwe were determined. The main VAM genera Acaulospora, Scutellospora, Gigaspora, Glomus, Sclerocystis and Entrophospora were represented in the study sites. The relative abundance was ...

Effect of two vesicular-arbuscular mycorrhizal fungi on the growth of micropropagated potato plantlets and on the extent of disease caused by Rhizoctonia solani.

Science.gov (United States)

Yao, M K; Tweddell, R J; Désilets, H

2002-10-01

Two micropropagated potato cultivars, Goldrush and LP89221, were inoculated into sowing trays with either Glomus etunicatum or G. intraradices in a greenhouse. After 2 weeks, plantlets were transplanted into pots and roots were challenged 7 days later with Rhizoctonia solani. At different times after R. solani infection, disease severity, mortality rate, root colonization levels, various growth parameters, and shoot mineral content were evaluated. In Goldrush, only inoculation with G. etunicatum led to a significant reduction in disease severity, ranging between 60.2% and 71.2%, on both shoot and crown. This decrease was not observed in LP89221. Compared with the control plantlets, inoculation of Goldrush with G. etunicatum or G. intraradices reduced significantly the mortality rate by 77% and 26%, respectively, whereas vesicular-arbuscular mycorrhizal (VAM) fungi did not significantly influence the mortality rate in LP89221. In Goldrush, inoculation with G. etunicatum significantly increased shoot fresh weight, root dry weight and the number of tubers produced per plant, whereas G. intraradices only significantly increased the number of tubers. Tuber and root fresh weights of both potato cultivars were significantly reduced by R. solani infection. However, R. solani-infected plantlets of both Goldrush and LP89221, inoculated with G. etunicatum, produced significantly greater tuber fresh weight than non-VAM plantlets. In R. solani-infected plantlets of Goldrush but not LP89221, G. etunicatum and G. intraradices increased root fresh weight by approximately 140.3% and 76.5%, respectively, compared with non-VAM plants. The potato cultivars Goldrush and LP89221 responded differently to VAM fungal inoculation and to R. solani infection in terms of shoot mineral content.

Dihadron Azimuthal Correlations in p-p Collisions at sNN=7 TeV and p-Pb Collisions at sNN=5.02 TeV

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Ting Bai

2015-01-01

Full Text Available The dihadron azimuthal correlations in p-p collisions at sNN=7 TeV and p-Pb collisions at sNN=5.02 TeV are investigated in the framework of a multisource thermal model. The model can approximately describe the experimental results measured in the Large Hadron Collider. We find the px amplitude of the source is magnified and the source translates along the direction.

Molecular characterization of the 30-AA N-terminal mineral interaction domain of the biomineralization protein AP7.

Science.gov (United States)

Kim, Il Won; Morse, Daniel E; Evans, John Spencer

2004-12-21

The AP7 protein is one of several mollusk shell proteins which are responsible for aragonite polymorph formation and stabilization within the nacre layer of the Pacific red abalone, H. rufescens. Previously, we demonstrated that the 30-AA N-terminal domain of AP7, denoted as AP7-1, exists as an unfolded sequence and possesses the capability of inhibiting calcium carbonate crystal growth in vitro via growth step frustration or interruption. However, very little is known with regard to the interactive capabilities of this sequence with Ca(II) and with calcium carbonates. Using multidisciplinary techniques, we determine that the AP7-1 polypeptide interacts with Ca(II) ions at the -DD- sequence clusters, yet retains its unfolded, conformationally labile structure in the presence of Ca(II) ions. Further, NMR experiments reveal that the extended structured sequence blocks, -GNGM-, -SVRTQG-, and -ISYL, exhibit motional, chemical exchange, and/or backbone geometry perturbations in response to Ca(II) interactions with AP7-1. Solid-state NMR magic angle spinning studies verify that during the course of in vitro calcium carbonate crystal growth, AP7-1 becomes bound to calcite fragments and cannot be entirely displaced from the mineral fragments using competitive Ca(II) washing. Finally, using a scrambled sequence version of the AP7-1 polypeptide, we observe that sequence scrambling does not adversely affect the crystal growth inhibitory activity of AP7-1, suggesting that the amino acid composition of AP7-1 may be more critical to growth step inhibition than the linear ordering of amino acids.

The ANGULATA7 gene encodes a DnaJ-like zinc finger-domain protein involved in chloroplast function and leaf development in Arabidopsis.

Science.gov (United States)

Muñoz-Nortes, Tamara; Pérez-Pérez, José Manuel; Ponce, María Rosa; Candela, Héctor; Micol, José Luis

2017-03-01

The characterization of mutants with altered leaf shape and pigmentation has previously allowed the identification of nuclear genes that encode plastid-localized proteins that perform essential functions in leaf growth and development. A large-scale screen previously allowed us to isolate ethyl methanesulfonate-induced mutants with small rosettes and pale green leaves with prominent marginal teeth, which were assigned to a phenotypic class that we dubbed Angulata. The molecular characterization of the 12 genes assigned to this phenotypic class should help us to advance our understanding of the still poorly understood relationship between chloroplast biogenesis and leaf morphogenesis. In this article, we report the phenotypic and molecular characterization of the angulata7-1 (anu7-1) mutant of Arabidopsis thaliana, which we found to be a hypomorphic allele of the EMB2737 gene, which was previously known only for its embryonic-lethal mutations. ANU7 encodes a plant-specific protein that contains a domain similar to the central cysteine-rich domain of DnaJ proteins. The observed genetic interaction of anu7-1 with a loss-of-function allele of GENOMES UNCOUPLED1 suggests that the anu7-1 mutation triggers a retrograde signal that leads to changes in the expression of many genes that normally function in the chloroplasts. Many such genes are expressed at higher levels in anu7-1 rosettes, with a significant overrepresentation of those required for the expression of plastid genome genes. Like in other mutants with altered expression of plastid-encoded genes, we found that anu7-1 exhibits defects in the arrangement of thylakoidal membranes, which appear locally unappressed. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Knowing, Applying, and Reasoning about Arithmetic: Roles of Domain-General and Numerical Skills in Multiple Domains of Arithmetic Learning

Science.gov (United States)

Zhang, Xiao; Räsänen, Pekka; Koponen, Tuire; Aunola, Kaisa; Lerkkanen, Marja-Kristiina; Nurmi, Jari-Erik

2017-01-01

The longitudinal relations of domain-general and numerical skills at ages 6-7 years to 3 cognitive domains of arithmetic learning, namely knowing (written computation), applying (arithmetic word problems), and reasoning (arithmetic reasoning) at age 11, were examined for a representative sample of 378 Finnish children. The results showed that…

Individual globular domains and domain unfolding visualized in overstretched titin molecules with atomic force microscopy.

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Zsolt Mártonfalvi

Full Text Available Titin is a giant elastomeric protein responsible for the generation of passive muscle force. Mechanical force unfolds titin's globular domains, but the exact structure of the overstretched titin molecule is not known. Here we analyzed, by using high-resolution atomic force microscopy, the structure of titin molecules overstretched with receding meniscus. The axial contour of the molecules was interrupted by topographical gaps with a mean width of 27.7 nm that corresponds well to the length of an unfolded globular (immunoglobulin and fibronectin domain. The wide gap-width distribution suggests, however, that additional mechanisms such as partial domain unfolding and the unfolding of neighboring domain multimers may also be present. In the folded regions we resolved globules with an average spacing of 5.9 nm, which is consistent with a titin chain composed globular domains with extended interdomain linker regions. Topographical analysis allowed us to allocate the most distal unfolded titin region to the kinase domain, suggesting that this domain systematically unfolds when the molecule is exposed to overstretching forces. The observations support the prediction that upon the action of stretching forces the N-terminal ß-sheet of the titin kinase unfolds, thus exposing the enzyme's ATP-binding site and hence contributing to the molecule's mechanosensory function.

Microstructures of GaN1-xPx layers grown on (0001) GaN substrates by gas source molecular beam epitaxy

Science.gov (United States)

Seong, Tae-Yeon; Bae, In-Tae; Choi, Chel-Jong; Noh, D. Y.; Zhao, Y.; Tu, C. W.

1999-03-01

Transmission electron microscope (TEM), transmission electron diffraction (TED), and synchrotron x-ray diffraction (XRD) studies have been performed to investigate microstructural behavior of gas source molecular beam epitaxial GaN1-xPx layers grown on (0001) GaN/sapphire at temperatures (Tg) in the range 500-760 °C. TEM, TED, and XRD results indicate that the samples grown at Tg⩽600 °C undergo phase separation resulting in a mixture of GaN-rich and GaP-rich GaNP with zinc-blende structure. However, the samples grown at Tg⩾730 °C are found to be binary zinc-blende GaN(P) single crystalline materials. As for the 500 °C layer, the two phases are randomly oriented and distributed, whereas the 600 °C layer consists of phases that are elongated and inclined by 60°-70° clockwise from the [0001]α-GaN direction. The samples grown at Tg⩾730 °C are found to consist of two types of microdomains, namely, GaN(P)I and GaN(P)II; the former having twin relation to the latter.

Structural Basis for Endosomal Targeting by the Bro1 Domain

Science.gov (United States)

Kim, Jaewon; Sitaraman, Sujatha; Hierro, Aitor; Beach, Bridgette M.; Odorizzi, Greg; Hurley, James H.

2010-01-01

Summary Proteins delivered to the lysosome or the yeast vacuole via late endosomes are sorted by the ESCRT complexes and by associated proteins, including Alix and its yeast homolog Bro1. Alix, Bro1, and several other late endosomal proteins share a conserved 160 residue Bro1 domain whose boundaries, structure, and function have not been characterized. The crystal structure of the Bro1 domain of Bro1 reveals a folded core of 367 residues. The extended Bro1 domain is necessary and sufficient for binding to the ESCRT-III subunit Snf7 and for the recruitment of Bro1 to late endosomes. The structure resembles a boomerang with its concave face filled in and contains a triple tetratricopeptide repeat domain as a substructure. Snf7 binds to a conserved hydrophobic patch on Bro1 that is required for protein complex formation and for the protein-sorting function of Bro1. These results define a conserved mechanism whereby Bro1 domain-containing proteins are targeted to endosomes by Snf7 and its orthologs. PMID:15935782

A novel gene whose expression in Medicago truncatula roots is suppressed in response to colonization by vesicular-arbuscular mycorrhizal (VAM) fungi and to phosphate nutrition.

Science.gov (United States)

Burleigh, S H; Harrison, M J

1997-05-01

A cDNA clone (Mt4) was isolated as a result of a differential screen to identify genes showing altered expression during the interaction between Medicago truncatula and the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus versiforme. Mt4 represents a M. truncatula mRNA that contains numerous short open reading frames, the two longest of which are predicted to encode polypeptides of 51 amino acids each. One of these open reading frames shares a short region of identity with a phosphate starvation-inducible gene from tomato. Mt4 gene expression is regulated in response to colonization by mycorrhizal fungi: transcripts were detected in non-colonized roots and levels decreased in both M. truncatula and M. sativa (alfalfa) roots after colonization by G. versiforme. Transcript levels also decreased during the incomplete interaction between G. versiforme and a M. sativa mycorrhizal minus (myc-) line, indicating that the down-regulation of this gene occurs early during the interaction between the fungus and its host plant. Phosphate levels in the nutrient media also affected the expression of the Mt4 gene: transcripts were present in the roots of plants grown under phosphate-deficient conditions, but were undetectable in the roots of plants grown under phosphate sufficient conditions. Furthermore, expression was only observed when plants were grown under nitrogen-sufficient conditions. Northern blot analyses indicate that Mt4 transcripts are present primarily in roots and barely detectable in stems or leaves. Thus, Mt4 represents a M. truncatula gene whose expression is regulated in response to both colonization by mycorrhizal fungi and to the phosphate status of the plant.

Theoretical investigation of the structural stabilities, optoelectronic properties and thermodynamic characteristics of GaPxSb1-x ternary alloys

Science.gov (United States)

Oumelaz, F.; Nemiri, O.; Boumaza, A.; Ghemid, S.; Meradji, H.; Bin Omran, S.; El Haj Hassan, F.; Rai, D. P.; Khenata, R.

2018-06-01

In this theoretical study, we have investigated the structural, phase transition, electronic, thermodynamic and optical properties of GaPxSb1-x ternary alloys. Our calculations are performed with the WIEN2k code based on density functional theory using the full-potential linearized augmented plane wave method. For the electron exchange-correlation potential, a generalized gradient approximation within Wu-Cohen scheme is considered. The recently developed Tran-Blaha modified Becke-Johnson potential has also been used to improve the underestimated band gap. The structural properties, including the lattice constants, the bulk moduli and their pressure derivatives are in very good agreement with the available experimental data and theoretical results. Several structural phase transitions were studied here to establish the stable structure and to predict the phase transition under hydrostatic pressure. The computed transition pressure (Pt) of the material of our interest from the zinc blende (B3) to the rock salt (B1) phase has been determined and found to agree well with the experimental and theoretical data. The calculated band structure shows that GaSb binary compound and the ternary alloys are direct band gap semiconductors. Optical parameters such as the dielectric constants and the refractive indices are calculated and analyzed. The thermodynamic results are also interpreted and analyzed.

The development and significance of vesicular-arbuscular mycorrhizas as influenced by agricultural practices

NARCIS (Netherlands)

Ruissen, M.A.

1982-01-01

The development and significance of vesicular- arbuscular mycorrhizas (VAM) in wheat and potatoes have been studied in relation to various farming systems and agricultural practices. The effects of farming systems on VAM have been observed on three neighbouring experimental farms in the vicinity of

Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops

DEFF Research Database (Denmark)

Jakobsen, Iver

1986-01-01

The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm...... in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard...

COST 296 scientific results designed for operational use

Directory of Open Access Journals (Sweden)

Michael Pezzopane

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">The main objective of the COST 296 Action «Mitigation of Ionospheric Effects on Radio Systems» is the establishment/

px 0.0px 0.0px 0.0px; font: 9.0px Times;">improvement of ionospheric services by coordinating the development of specific algorithms, models,

px 0.0px 0.0px 0.0px; font: 9.0px Times;">and tools capable of operating in a near-real-time mode.

px 0.0px 0.0px 0.0px; font: 9.0px Times;">Key elements of these activities are contributions related to monitoring, modelling, and imaging of customer-relevant

px 0.0px 0.0px 0.0px; font: 9.0px Times;">ionospheric quantities. COST stimulates, coordinates, and supports Europe’s goals of development and

px 0.0px 0.0px 0.0px; font: 9.0px Times;">global cooperation by providing high quality information and knowledge of ionospheric and plasmaspheric conditions

px 0.0px 0.0px 0.0px; font: 9.0px Times;">enabling high quality and reliable operation of radio systems.

px 0.0px 0.0px 0.0px; font: 9.0px Times;">It also provides a platform for sharing such tools as algorithms or models, and for the joint development of advanced

px 0.0px 0.0px 0.0px; font: 9.0px Times;">technologies. It takes advantage of many national and European service initiatives, for example DIAS

px 0.0px 0.0px 0.0px; font: 9.0px Times;">(http://dias.space.noa.gr, SWACI (http://w3swaci.dlr.de, ESWUA (http://www.eswua.ingv.it/ingv, RWC-Warsaw

px 0.0px 0.0px 0.0px; font: 9.0px Times;">(http://www.cbk.waw.pl/rwc, the COST Prompt Ionospheric Database http://www.wdc.rl.ac.uk/cgibin/

px 0.0px 0.0px 0.0px; font: 9.0px Times;">digisondes/cost_database.pl, http://www.izmiran.ru/services, and others.

Aspects of HF radio propagation

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Stephane Saillant

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">radio systems. From the point of view Working Group 2 of the COST 296 Action, interest lies with effects associated

px 0.0px 0.0px 0.0px; font: 9.0px Times;">with propagation via the ionosphere of signals within the HF band. Several aspects are covered in this paper:

px 0.0px 0.0px 0.0px; font: 9.0px Times;">a The directions of arrival and times of flight of signals received over a path oriented along the trough have

px 0.0px 0.0px 0.0px; font: 9.0px Times;">been examined and several types of propagation effects identified. Of particular note, combining the HF observations

px 0.0px 0.0px 0.0px; font: 9.0px Times;">with satellite measurements has identified the presence of irregularities within the floor of the trough that

px 0.0px 0.0px 0.0px; font: 9.0px Times;">result in propagation displaced from the great circle direction. An understanding of the propagation effects that

px 0.0px 0.0px 0.0px; font: 9.0px Times;">result in deviations of the signal path from the great circle direction are of particular relevance to the operation

px 0.0px 0.0px 0.0px; font: 9.0px Times;">of HF radiolocation systems.

px 0.0px 0.0px 0.0px; font: 9.0px Times;">b Inclusion of the results from the above mentioned measurements into a propagation model of the northerly

px 0.0px 0.0px 0.0px; font: 9.0px Times;">ionosphere (i.e. those regions of the ionosphere located poleward of, and including, the mid-latitude trough

px 0.0px 0.0px 0.0px; font: 9.0px Times;">and the use of this model to predict the coverage expected from transmitters where the signals impinge on the

px 0.0px 0.0px 0.0px; font: 9.0px Times;">northerly ionosphere

Domain Adaptation for Machine Translation with Instance Selection

Directory of Open Access Journals (Sweden)

Biçici Ergun

2015-04-01

Full Text Available Domain adaptation for machine translation (MT can be achieved by selecting training instances close to the test set from a larger set of instances. We consider 7 different domain adaptation strategies and answer 7 research questions, which give us a recipe for domain adaptation in MT. We perform English to German statistical MT (SMT experiments in a setting where test and training sentences can come from different corpora and one of our goals is to learn the parameters of the sampling process. Domain adaptation with training instance selection can obtain 22% increase in target 2-gram recall and can gain up to 3:55 BLEU points compared with random selection. Domain adaptation with feature decay algorithm (FDA not only achieves the highest target 2-gram recall and BLEU performance but also perfectly learns the test sample distribution parameter with correlation 0:99. Moses SMT systems built with FDA selected 10K training sentences is able to obtain F1 results as good as the baselines that use up to 2M sentences. Moses SMT systems built with FDA selected 50K training sentences is able to obtain F1 point better results than the baselines.

Utilization of antenna arrays in HF systems

Directory of Open Access Journals (Sweden)

Louis Bertel

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">Different applications of radio systems are based on the implementation of antenna arrays. Classically, radio direction

px 0.0px 0.0px 0.0px; font: 9.0px Times;">finding operates with a multi channel receiving system connected to an array of receiving antennas. More

px 0.0px 0.0px 0.0px; font: 9.0px Times;">recently, MIMO architectures have been proposed to increase the capacity of radio links by the use of antenna

px 0.0px 0.0px 0.0px; font: 9.0px Times;">arrays at both the transmitter and receiver.

px 0.0px 0.0px 0.0px; font: 9.0px Times;">The first part of this paper describes some novel experimental work carried out to examine the feasibility of applying

px 0.0px 0.0px 0.0px; font: 9.0px Times;">MIMO techniques for communications within the HF radio band. A detailed correlation analysis of a variety

px 0.0px 0.0px 0.0px; font: 9.0px Times;">of different antenna array configurations is presented. The second section of the paper also deals with HF

px 0.0px 0.0px 0.0px; font: 9.0px Times;">MIMO communications, focusing on the problem from a modelling point of view. The third part presents a sensitivity

px 0.0px 0.0px 0.0px; font: 9.0px Times;">analysis of different antenna array structures for HF direction finding applications. The results demonstrate

px 0.0px 0.0px 0.0px; font: 9.0px Times;">that when modelling errors, heterogeneous antenna arrays are more robust in comparison to homogeneous structures

The Implications of Summer Learning Loss for Value-Added Estimates of Teacher Effectiveness

Science.gov (United States)

Gershenson, Seth; Hayes, Michael S.

2018-01-01

School districts across the United States increasingly use value-added models (VAMs) to evaluate teachers. In practice, VAMs typically rely on lagged test scores from the previous academic year, which necessarily conflate summer with school-year learning and potentially bias estimates of teacher effectiveness. We investigate the practical…

Examining the Relationship between Technological Pedagogical Content Knowledge (TPACK) and Student Achievement Utilizing the Florida Value-Added Model

Science.gov (United States)

Farrell, Ivan K.; Hamed, Kastro M.

2017-01-01

Utilizing a correlational research design, we sought to examine the relationship between the technological pedagogical content knowledge (TPACK) of in-service teachers and student achievement measured with each individual teacher's Value-Added Model (VAM) score. The TPACK survey results and a teacher's VAM score were also examined, separately,…

A randomized trial of cardiopulmonary resuscitation training for medical students: voice advisory mannequin compared to guidance provided by an instructor.

Science.gov (United States)

Díez, Nieves; Rodríguez-Díez, María-Cristina; Nagore, David; Fernández, Secundino; Ferrer, Marta; Beunza, Juan-Jose

2013-08-01

Current European Resuscitation Guidelines 2010 recommend the use of prompt/feedback devices when training for cardiopulmonary resuscitation (CPR). We aimed to assess the quality of CPR training among second-year medical students with a voice advisory mannequin (VAM) compared to guidance provided by an instructor. Forty-three students received a theoretical reminder about CPR followed by a 2-minute pretest on CPR (compressions/ventilations cycle) with Resusci Anne SkillReporter (Laerdal Medical). They were then randomized into a control group (n = 22), trained by an instructor for 4 minutes per student, and an intervention group (n = 21) trained individually with VAM CPR mannequin for 4 minutes. After training, the students performed a 2-minute posttest, with the same method as the pretest. Participants in the intervention group (VAM) performed more correct hand position (73% vs. 37%; P = 0.014) and tended to display better compression rate (124 min vs. 135 min; P = 0.089). In a stratified analyses by sex we found that only among women trained with VAM was there a significant improvement in compression depth before and after training (36 mm vs. 46 mm, P = 0.018) and in the percentage of insufficient compressions before and after training (56% vs. 15%; P = 0.021). In comparison to the traditional training method involving an instructor, training medical students in CPR with VAM improves the quality of chest compressions in hand position and in compression rate applied to mannequins. Only among women was VAM shown to be superior in compression depth training. This technology reduces costs in 14% in our setup and might potentially release instructors' time for other activities.

Effect of mycorrhizal fungi on the phytoextraction of weathered p,p-DDE by Cucurbita pepo.

Science.gov (United States)

White, Jason C; Ross, Daniel W; Gent, Martin P N; Eitzer, Brian D; Mattina, Maryjane Incorvia

2006-10-11

Field experiments were conducted to assess the impact of inoculation with mycorrhizal fungi on the accumulation of weathered p,p'-DDE from soil by three cultivars of zucchini (Cucurbita pepo spp. pepo cv Costata Romanesco, Goldrush, Raven). Three commercially available mycorrhizal products (BioVam, Myco-Vam, INVAM) were inoculated into the root system of the zucchini seedlings at planting. In agreement with our previous findings, plants not inoculated with fungi accumulated large but variable amounts of contaminant, with root bioconcentration factors (BCFs, ratio of p,p'-DDE, on a dry weight basis, in the root to that in the soil) ranging from 10 to 48 and stem BCFs ranging from 5.5 to 11. The total amount of contaminant phytoextracted during the 62 day growing season ranged from 0.72-2.9%. The effect of fungal inoculation on the release of weathered p,p'-DDE from soil and on the subsequent uptake of the parent compound by zucchini appeared to vary at the cultivar level. For Goldrush, fungal inoculation generally decreased tissue BCFs but because of slightly larger biomass, did not significantly impact the percent contaminant phytoextracted. Alternatively, for Costata, BioVam and Myco-Vam generally enhanced p,p'-DDE accumulation from soil, and increased the amount of contaminant phytoextracted by up to 34%. For Raven, BioVam reduced contaminant uptake whereas Myco-Vam and INVAM increased contaminant phytoextraction by 53 and 60%, respectively. The data show that fungal inoculation may significantly increase the remedial potential of C. pepo ssp. pepo. The apparent cultivar specific response to mycorrhizal inoculation is unexpected and the subject of ongoing investigation.

DNA Recognition by the DNA Primase of Bacteriophage T7: A Structure Function Study of the Zinc-Binding Domain

International Nuclear Information System (INIS)

Akabayov, B.; Lee, S.; Akabayov, S.; Rekhi, S.; Zhu, B.; Richardson, C.

2009-01-01

Synthesis of oligoribonucleotide primers for lagging-strand DNA synthesis in the DNA replication system of bacteriophage T7 is catalyzed by the primase domain of the gene 4 helicase-primase. The primase consists of a zinc-binding domain (ZBD) and an RNA polymerase (RPD) domain. The ZBD is responsible for recognition of a specific sequence in the ssDNA template whereas catalytic activity resides in the RPD. The ZBD contains a zinc ion coordinated with four cysteine residues. We have examined the ligation state of the zinc ion by X-ray absorption spectroscopy and biochemical analysis of genetically altered primases. The ZBD of primase engaged in catalysis exhibits considerable asymmetry in coordination to zinc, as evidenced by a gradual increase in electron density of the zinc together with elongation of the zinc-sulfur bonds. Both wild-type primase and primase reconstituted from purified ZBD and RPD have a similar electronic change in the level of the zinc ion as well as the configuration of the ZBD. Single amino acid replacements in the ZBD (H33A and C36S) result in the loss of both zinc binding and its structural integrity. Thus the zinc in the ZBD may act as a charge modulation indicator for the surrounding sulfur atoms necessary for recognition of specific DNA sequences.

The Development of Early Childhood Education as an Academic Discipline in Finland

Directory of Open Access Journals (Sweden)

Eeva Hujala

2008-10-01

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px 0.0px 0.0px 0.0px; font: 10.0px Times;">Early Childhood Education (ECE as an academic discipline has gained an academic legitimacy in Fin-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">land in 2005. In accordance with internationally established practice, Early Childhood Education as an academic 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">field and a field of research has been set to cover the period from birth to eight years of age. The focus of ECE re-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">search is to analyse and define the development and upbringing of young children, including such themes as 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">learning and teaching and the complex connection between child development to the growth environment. In re-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">cent years in Finland, the internal paradigmatic discussions within academic ECE have been both enlightened and 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">critical. The emergence of an academic Early Childhood Education paradigm has been apparent in the discus-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">sions of early pedagogy, professional growth, leadership, management and quality and as a definer of pedagogy 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">to support children’s learning. The challenge of academic Early Childhood Education is to introduce into the dis-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">cussion ontological and epistemological issues of early childhood and thereby activate teachers and other

Från görande till lärande och förståelse; En studie av lärares lärande inom estetik

Directory of Open Access Journals (Sweden)

Maj Asplund Carlsson

2008-10-01

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px 0.0px 0.0px 0.0px; font: 10.0px Times;">The aim of this article is to analyse teachers’ changing ways of talking about children’s aesthetic learn-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">ing in the early years as a result of a research and development project. With a point of departure in developmen-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">tal and variation theory, a praxis oriented project was designed with the aim of finding out whether collaborative 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">talk and meta-cognitive dialogues could contribute to children’s learning of music, dance and poetry. The partici-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">pating teachers were offered in-service training in order to develop a new way of teaching and new ways of think-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">ing about the curriculum and children’s learning. Interviews with the teachers were carried out at the beginning 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">and the end of the project. The teachers’ learning was expressed in changed ways of talking about aesthetics and 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">learning. From an emphasis on personality development and the teacher’s lack of expertise with the aesthetic sub-px Helvetica;"> 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">jects as an obstacle, the teachers expressed a view of having become more aware of the concept of learning objects 

px 0.0px 0.0px 0.0px; font: 10.0px Times;">in the aesthetics, of their own role as teachers in directing

Identification of transmembrane domain 6 & 7 residues that contribute to the binding pocket of the urotensin II receptor.

Science.gov (United States)

Holleran, Brian J; Domazet, Ivana; Beaulieu, Marie-Eve; Yan, Li Ping; Guillemette, Gaétan; Lavigne, Pierre; Escher, Emanuel; Leduc, Richard

2009-04-15

Urotensin II (U-II), a cyclic undecapeptide, is the natural ligand of the urotensin II (UT) receptor, a G protein-coupled receptor. In the present study, we used the substituted-cysteine accessibility method to identify specific residues in transmembrane domains (TMDs) six and seven of the rat urotensin II receptor (rUT) that contribute to the formation of the binding pocket of the receptor. Each residue in the R256(6.32)-Q283(6.59) fragment of TMD6 and the A295(7.31)-T321(7.57) fragment of TMD7 was mutated, individually, to a cysteine. The resulting mutants were expressed in COS-7 cells, which were subsequently treated with the positively charged methanethiosulfonate-ethylammonium (MTSEA) or the negatively charged methanethiosulfonate-ethylsulfonate (MTSES) sulfhydryl-specific alkylating agents. MTSEA treatment resulted in a significant reduction in the binding of TMD6 mutants F268C(6.44) and W278C(6.54) and TMD7 mutants L298C(7.34), T302C(7.38), and T303C(7.39) to (125)I-U-II. MTSES treatment resulted in a significant reduction in the binding of two additional mutants, namely L282C(6.58) in TMD6 and Y300C(7.36) in TMD7. These results suggest that specific residues orient themselves within the water-accessible binding pocket of the rUT receptor. This approach, which allowed us to identify key determinants in TMD6 and TMD7 that contribute to the UT receptor binding pocket, enabled us to further refine our homology-based model of how U-II interacts with its cognate receptor.

Comparison of vesicular-arbuscular mycorrhizae in plants from disturbed and adjacent undisturbed regions of a coastal salt marsh in Clinton, Connecticut, USA

Science.gov (United States)

Cooke, John C.; Lefor, Michael W.

1990-01-01

Roots of salt marsh plant species Spartina alterniflora, S. patens, Distichlis spicata, and others were examined for the presence of vesicular-arbuscular mycorrhizal (VAM) fungi. Samples were taken from introduced planted material in a salt marsh restoration project and from native material in adjacent marsh areas along the Indian River, Clinton, Connecticut, USA. After ten years the replanted area still has sites devoid of vegetation. The salt marsh plants introduced there were devoid of VAM fungi, while high marsh species from the adjacent undisturbed region showed consistent infection, leading the authors to suggest that VAM fungal infection of planting stocks may be a factor in the success of marsh restoration.

Climate of the upper atmosphere

Directory of Open Access Journals (Sweden)

Christoph Jacobi

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS

px 0.0px 0.0px 0.0px; font: 9.0px Times;">investigations of the climate of the upper atmosphere have been carried out during the last four years to obtain

px 0.0px 0.0px 0.0px; font: 9.0px Times;">new information on the upper atmosphere. Mainly its ionospheric part has been analysed as the ionosphere

px 0.0px 0.0px 0.0px; font: 9.0px Times;">most essential for the propagation of radio waves. Due to collaboration between different European partners

px 0.0px 0.0px 0.0px; font: 9.0px Times;">many new results have been derived in the fields of long-term trends of different ionospheric and related atmospheric

px 0.0px 0.0px 0.0px; font: 9.0px Times;">parameters, the investigations of different types of atmospheric waves and their impact on the ionosphere,

px 0.0px 0.0px 0.0px; font: 9.0px Times;">the variability of the ionosphere, and the investigation of some space weather effects on the ionosphere.

Cloning, ligand-binding, and temporal expression of ecdysteroid receptors in the diamondback moth, Plutella xylostella

Directory of Open Access Journals (Sweden)

Tang Baozhen

2012-10-01

Full Text Available Abstract Background The diamondback moth, Plutella xylostella (L. (Lepidoptera: Plutellidae, is a devastating pest of cruciferous crops worldwide, and has developed resistance to a wide range of insecticides, including diacylhydrazine-based ecdysone agonists, a highly selective group of molt-accelerating biopesticides targeting the ecdysone receptors. Result In this study, we cloned and characterized the ecdysone receptors from P. xylostella, including the two isoforms of EcR and a USP. Sequence comparison and phylogenetic analysis showed striking conservations among insect ecdysone receptors, especially between P. xylostella and other lepidopterans. The binding affinity of ecdysteroids to in vitro-translated receptor proteins indicated that PxEcRB isoform bound specifically to ponasterone A, and the binding affinity was enhanced by co-incubation with PxUSP (Kd =3.0±1.7 nM. In contrast, PxEcRA did not bind to ponasterone A, even in the presence of PxUSP. The expression of PxEcRB were consistently higher than that of PxEcRA across each and every developmental stage, while the pattern of PxUSP expression is more or less ubiquitous. Conclusions Target site insensitivity, in which the altered binding of insecticides (ecdysone agonists to their targets (ecdysone receptors leads to an adaptive response (resistance, is one of the underlying mechanisms of diacylhydrazine resistance. Given the distinct differences at expression level and the ligand-binding capacity, we hypothesis that PxEcRB is the ecdysone receptor that controls the remodeling events during metamorphosis. More importantly, PxEcRB is the potential target site which is modified in the ecdysone agonist-resistant P. xylostella.

Alternate fuels and chemicals from synthesis gas: Vinyl acetate monomer. Final report

Energy Technology Data Exchange (ETDEWEB)

Richard D. Colberg; Nick A. Collins; Edwin F. Holcombe; Gerald C. Tustin; Joseph R. Zoeller

1999-01-01

There has been a long-standing desire on the part of industry and the U.S. Department of Energy to replace the existing ethylene-based vinyl acetate monomer (VAM) process with an entirely synthesis gas-based process. Although there are a large number of process options for the conversion of synthesis gas to VAM, Eastman Chemical Company undertook an analytical approach, based on known chemical and economic principles, to reduce the potential candidate processes to a select group of eight processes. The critical technologies that would be required for these routes were: (1) the esterification of acetaldehyde (AcH) with ketene to generate VAM, (2) the hydrogenation of ketene to acetaldehyde, (3) the hydrogenation of acetic acid to acetaldehyde, and (4) the reductive carbonylation of methanol to acetaldehyde. This report describes the selection process for the candidate processes, the successful development of the key technologies, and the economic assessments for the preferred routes. In addition, improvements in the conversion of acetic anhydride and acetaldehyde to VAM are discussed. The conclusion from this study is that, with the technology developed in this study, VAM may be produced from synthesis gas, but the cost of production is about 15% higher than the conventional oxidative acetoxylation of ethylene, primarily due to higher capital associated with the synthesis gas-based processes.

Pigeon Pea and Cowpea-Based Cropping Systems Improve Vesicular Arbuscular Mycorrhizal Fungal Colonisation of Subsequent Maize on the Alfisols in Central Malawi

Directory of Open Access Journals (Sweden)

Keston O. W. Njira

2017-01-01

Full Text Available Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole cropping, legume-cereal, and legume-legume intercropping systems and in the maize grown in short rotation (year 2 as influenced by the previous cropping systems and N fertilizer application. The gridline intersect method was used to assess the VAM fungal colonisation levels. Results showed that all treatments that included legumes whether grown as sole crop, in legume-cereal or in legume-legume cropping systems in the previous year, had significantly higher (P < 0.05 VAM fungal colonisation of the rotational maize crop roots by a range 39% to 50% and 19% to 47% than those in maize supplied and not supplied with N fertilizer, respectively, in a maize-maize short rotation, at the Lilongwe site. A similar trend was reported for the Dowa site. Furthermore, there were positive correlations between VAM fungal colonisation and the plant P content, dry matter yield, and nodule numbers. Further studies may help to assess the diversity of VAM fungal species in Malawi soils and identify more adaptive ones for inoculation studies.

Video-assisted mediastinoscopic resection compared with video-assisted thoracoscopic surgery in patients with esophageal cancer.

Science.gov (United States)

Wang, Qian-Yun; Tan, Li-Jie; Feng, Ming-Xiang; Zhang, Xiao-Ying; Zhang, Lei; Jiang, Nan-Qing; Wang, Zhong-Lin

2014-06-01

The purpose of this study was to explore the indications of radical vedio-assisted mediastinoscopic resection for esophageal cancer. The data of 109 patients with T1 esophageal cancer who underwent video-assisted mediastinoscopic resection (VAMS group) in Third Affiliated Hospital of Soochow University Hospital from December 2005 to December 2011 were collected in the study for comparison with the 58 patients with T1 esophageal cancer who underwent video-assisted thoracoscopic surgery (VATS group) in Zhongshan Hospital, Fudan University. The perioperative safety and survival were compared between the two groups. All operations were successful in both groups. One perioperative death was noted in the VATS group. The incidences of post-operative complications were not significantly different between these two groups, whereas the VAMS group was favorable in terms of operative time (P<0.001) and blood loss (P<0.001), and a significantly larger number of chest lymph nodes were dissected in the VATS group compared with the VAMS group (P<0.001). Long-term follow-up showed that the overall survival was not significantly different between these two groups (P=0.876). T1N0M0 esophageal cancer can be as the indication of VAMS radical resection. VAMS radical resection can be considered as the preferred option for patients with poor pulmonary and cardiac function or a history of pleural disease.

Structure of an isolated unglycosylated antibody CH2 domain

International Nuclear Information System (INIS)

Prabakaran, Ponraj; Vu, Bang K.; Gan, Jianhua; Feng, Yang; Dimitrov, Dimiter S.; Ji, Xinhua

2008-01-01

The crystal structure of an isolated unglycosylated antibody C H 2 domain has been determined at 1.7 Å resolution. The C H 2 (C H 3 for IgM and IgE) domain of an antibody plays an important role in mediating effector functions and preserving antibody stability. It is the only domain in human immunoglobulins (Igs) which is involved in weak interchain protein–protein interactions with another C H 2 domain solely through sugar moieties. The N-linked glycosylation at Asn297 is conserved in mammalian IgGs as well as in homologous regions of other antibody isotypes. To examine the structural details of the C H 2 domain in the absence of glycosylation and other antibody domains, the crystal structure of an isolated unglycosylated antibody γ1 C H 2 domain was determined at 1.7 Å resolution and compared with corresponding C H 2 structures from intact Fc, IgG and Fc receptor complexes. Furthermore, the oligomeric state of the protein in solution was studied using size-exclusion chromatography. The results suggested that the unglycosylated human antibody C H 2 domain is a monomer and that its structure is similar to that found in the intact Fc, IgG and Fc receptor complex structures. However, certain structural variations were observed in the Fc receptor-binding sites. Owing to its small size, stability and non-immunogenic Ig template, the C H 2-domain structure could be useful for the development by protein design of antibody domains exerting effector functions and/or antigen specificity and as a robust scaffold in protein-engineering applications

The PR-Set7 binding domain of Riz1 is required for the H4K20me1-H3K9me1 trans-tail ‘histone code’ and Riz1 tumor suppressor function

Science.gov (United States)

Congdon, Lauren M.; Sims, Jennifer K.; Tuzon, Creighton T.; Rice, Judd C.

2014-01-01

PR-Set7/Set8/KMT5a is the sole histone H4 lysine 20 monomethyltransferase (H4K20me1) in metazoans and is essential for proper cell division and genomic stability. We unexpectedly discovered that normal cellular levels of monomethylated histone H3 lysine 9 (H3K9me1) were also dependent on PR-Set7, but independent of its catalytic activity. This observation suggested that PR-Set7 interacts with an H3K9 monomethyltransferase to establish the previously reported H4K20me1-H3K9me1 trans-tail ‘histone code’. Here we show that PR-Set7 specifically and directly binds the C-terminus of the Riz1/PRDM2/KMT8 tumor suppressor and demonstrate that the N-terminal PR/SET domain of Riz1 preferentially monomethylates H3K9. The PR-Set7 binding domain was required for Riz1 nuclear localization and maintenance of the H4K20me1-H3K9me1 trans-tail ‘histone code’. Although Riz1 can function as a repressor, Riz1/H3K9me1 was dispensable for the repression of genes regulated by PR-Set7/H4K20me1. Frameshift mutations resulting in a truncated Riz1 incapable of binding PR-Set7 occur frequently in various aggressive cancers. In these cancer cells, expression of wild-type Riz1 restored tumor suppression by decreasing proliferation and increasing apoptosis. These phenotypes were not observed in cells expressing either the Riz1 PR/SET domain or PR-Set7 binding domain indicating that Riz1 methyltransferase activity and PR-Set7 binding domain are both essential for Riz1 tumor suppressor function. PMID:24423864

Value Added Methods: Moving from Univariate to Multivariate Criteria

Science.gov (United States)

Newman, David; Newman, Isadore; Ridenour, Carolyn; Morales, Jennifer

2014-01-01

The authors describe five value-added methods (VAM) used in school assessment as the backdrop to their main thesis. Then they review the assumptions underlying measurement and evaluation, the foundation of all assessment systems, including value-added. They discuss the traditional criterion variable used in VAM: a standardized test score. Next,…

Beyond cross-domain learning: Multiple-domain nonnegative matrix factorization

KAUST Repository

Wang, Jim Jing-Yan; Gao, Xin

2014-01-01

Traditional cross-domain learning methods transfer learning from a source domain to a target domain. In this paper, we propose the multiple-domain learning problem for several equally treated domains. The multiple-domain learning problem assumes that samples from different domains have different distributions, but share the same feature and class label spaces. Each domain could be a target domain, while also be a source domain for other domains. A novel multiple-domain representation method is proposed for the multiple-domain learning problem. This method is based on nonnegative matrix factorization (NMF), and tries to learn a basis matrix and coding vectors for samples, so that the domain distribution mismatch among different domains will be reduced under an extended variation of the maximum mean discrepancy (MMD) criterion. The novel algorithm - multiple-domain NMF (MDNMF) - was evaluated on two challenging multiple-domain learning problems - multiple user spam email detection and multiple-domain glioma diagnosis. The effectiveness of the proposed algorithm is experimentally verified. © 2013 Elsevier Ltd. All rights reserved.

Beyond cross-domain learning: Multiple-domain nonnegative matrix factorization

KAUST Repository

Wang, Jim Jing-Yan

2014-02-01

Traditional cross-domain learning methods transfer learning from a source domain to a target domain. In this paper, we propose the multiple-domain learning problem for several equally treated domains. The multiple-domain learning problem assumes that samples from different domains have different distributions, but share the same feature and class label spaces. Each domain could be a target domain, while also be a source domain for other domains. A novel multiple-domain representation method is proposed for the multiple-domain learning problem. This method is based on nonnegative matrix factorization (NMF), and tries to learn a basis matrix and coding vectors for samples, so that the domain distribution mismatch among different domains will be reduced under an extended variation of the maximum mean discrepancy (MMD) criterion. The novel algorithm - multiple-domain NMF (MDNMF) - was evaluated on two challenging multiple-domain learning problems - multiple user spam email detection and multiple-domain glioma diagnosis. The effectiveness of the proposed algorithm is experimentally verified. © 2013 Elsevier Ltd. All rights reserved.

Intra-tumoural vessel area estimated by expression of epidermal growth factor-like domain 7 and microRNA-126 in primary tumours and metastases of patients with colorectal cancer

DEFF Research Database (Denmark)

Hansen, T. F.; Nielsen, Boye Schnack; Jakobsen, Anders

2015-01-01

factor-like domain 7 (EGFL7) and microRNA-126 (miRNA-126) in primary tumours from patients with stage II-IV colorectal cancer (CRC) and in paired samples of primary tumours, regional lymph node metastases and distant metastases. Methods: A total of 126 patients were included. Analyses were performed...

Generic superconducting phase behavior in high-Tc cuprates: Tc variation with hole concentration in YBa2Cu3O7-δ

International Nuclear Information System (INIS)

Tallon, J.L.; Bernhard, C.; Shaked, H.; Hitterman, R.L.; Jorgensen, J.D.

1995-01-01

A direct determination of the relationship between T c and hole concentration p for Y 1-x Ca x Ba 2 Cu 3 O 7-δ is obtained by investigating the properties of the fully oxygen-deficient (δ∼1.0) compound for which p=x/2. Measurements of T c , the thermoelectric power S, and bond-valence sums calculated from neutron-diffraction refinements for various values of x and δ allow the full determination of the relations p=p(δ), T c =T c (p), and S=S(T,p) confirming that YBa 2 Cu 3 O 7-δ satisfies the same universal relations in these quantities as the other high-T c superconducting cuprates

PENGARUH INOKULASI MIKORIZA VESIKULA ARBUSKULA (MVA CAMPURAN TERHADAP KEMUNCULAN PENYAKIT LAYU FUSARIUM PADA TANAMAN TOMAT (Solanum lycopersicum

Directory of Open Access Journals (Sweden)

Uswatun Hasanah

2017-03-01

Full Text Available Tomato has an important role to fullfil the nutrition of society. The most important problem in the cultivation of tomatoes is fusarium wilt caused by Fusarium oxysporum it will attacking the plants from nursery to adult. One of the alternative control is use the Vesicles Arbuscular Mycorrhizae (VAM. The success of VAM infection in plants is determined by the dose and the inoculation. The aim of this research is to determine the effect of dose and mixture VAM inoculation to against the emergence of fusarium wilt in tomato plants and to determine the dosage mixture VAM inoculation as the most effective way for controlling fusarium wilt in tomato plants. The method of this research used experimental with completely randomized design. The experimental treatment consists of two types of treatment that are combined with used 5 doses of VAM mixture (0 g/plant, 10 g/plant, 12,5 g/plant, 15 g/plant, 17,5 g/plant and used two ways of inoculation ( inoculation when the seed is planted and inoculation when transplanting the seeds. Each treatment was repeated 3 times and each test are three plants. The parameters was observed the incubation period of the disease and the intensity of fusarium wilt as the main parameter and the measurement of pH, temperature, humidity room, and the degree of infection as supporting parameters. The results of this research showed that the dosage and inoculation of VAM mixture is not able to reduce the emergence of fusarium wilt on tomatoes, but it was able to extend the incubation period of fusarium wilt on tomato plants a dose with 10 g /plant inoculated plants when the seeds are planted and inoculation when transplanting the seeds.

Structural models of the human copper P-type ATPases ATP7A and ATP7B

DEFF Research Database (Denmark)

Gourdon, P.; Sitsel, Oleg; Karlsen, J.L.

2012-01-01

The human copper exporters ATP7A and ATP7B contain domains common to all P-type ATPases as well as class-specific features such as six sequential heavy-metal binding domains (HMBD1-HMBD6) and a type-specific constellation of transmembrane helices. Despite the medical significance of ATP7A and ATP7B......, allowing protein-specific properties to be addressed. Furthermore, the mapping of known disease-causing missense mutations indicates that among the heavy-metal binding domains, HMBD5 and HMBD6 are the most crucial for function, thus mimicking the single or dual HMBDs found in most copper-specific P-type...

Vacuum Exhaust Process in Pilot-Scale Vacuum Pressure Swing Adsorption for Coal Mine Ventilation Air Methane Enrichment

Directory of Open Access Journals (Sweden)

Xiong Yang

2018-04-01

Full Text Available Recovery and treatment of methane from coal mine ventilation air methane (VAM with cost-effective technologies have been an ongoing challenge due to low methane concentrations. In this study, a type of coconut shell-based active carbon was employed to enrich VAM with a three-bed vacuum pressure swing adsorption unit. A new vacuum exhaust step for the VPSA process was introduced. The results show that the vacuum exhaust step can increase the methane concentration of the product without changing adsorption and desorption pressure. Under laboratory conditions, the concentration of product increased from 0.4% to 0.69% as the vacuum exhaust ratio increased from 0 to 3.1 when the feed gas concentration was 0.2%. A 500 m³/h pilot-scale test system for VAM enrichment was built rendering good correlation with the laboratory results in terms of the vacuum exhaust step. By using a two-stage three-bed separation unit, the VAM was enriched from 0.2% to over 1.2%.

A plausible mechanism of biosorption in dual symbioses by vesicular-arbuscular mycorrhizal in plants.

Science.gov (United States)

Azmat, Rafia; Hamid, Neelofer

2015-03-01

Dual symbioses of vesicular-arbuscular mycorrhizal (VAM) fungi with growth of Momordica charantia were elucidated in terms of plausible mechanism of biosorption in this article. The experiment was conducted in green house and mixed inoculum of the VAM fungi was used in the three replicates. Results demonstrated that the starch contents were the main source of C for the VAM to builds their hyphae. The increased plant height and leaves surface area were explained in relation with an increase in the photosynthetic rates to produce rapid sugar contents for the survival of plants. A decreased in protein, and amino acid contents and increased proline and protease activity in VAM plants suggested that these contents were the main bio-indicators of the plants under biotic stress. The decline in protein may be due to the degradation of these contents, which later on converted into dextrose where it can easily be absorbed by for the period of symbioses. A mechanism of C chemisorption in relation with physiology and morphology of plant was discussed.

Reduction of bacterial growth by a vesicular-arbuscular mycorrhizal fungus in the rhizosphere of cucumber (Cucumis sativus L.)

DEFF Research Database (Denmark)

Christensen, H.; Jakobsen, I.

1993-01-01

Cucumber was grown in a partially sterilized sand-soil mixture with the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus fasciculatum or left uninoculated. Fresh soil extract was places in polyvinyl chloride tubes without propagules of mycorrhizal fungi. Root tips and root segments...... and top of tubes, and of cocci with a diameter of 0.55-0.78 mum in the bulk soil in the center of tubes, were significantly reduced by VAM fungi. The extremely high bacterial biomass (1-7 mg C g-1 dry weight soil) was significant reduced by mycorrhizal colonization on root segments and in bulk soil...... biomass, and changed the spatial pattern of bacterial growth compared to non-mycorrhizal cucumbers. The [H-3]-thymidine incorporation was significantly higher on root tips in the top of tubes, and on root segments and bulk soil in the center of tubes on non-mycorrhizal plants compared to mycorrhizal...

Cotesia vestalis parasitization suppresses expression of a Plutella xylostella thioredoxin.

Science.gov (United States)

Shi, M; Zhao, S; Wang, Z-H; Stanley, D; Chen, X-X

2016-12-01

Thioredoxins (Trxs) are a family of small, highly conserved and ubiquitous proteins involved in protecting organisms against toxic reactive oxygen species. In this study, a typical thioredoxin gene, PxTrx, was isolated from Plutella xylostella. The full-length cDNA sequence is composed of 959 bp containing a 321 bp open reading frame that encodes a predicted protein of 106 amino acids, a predicted molecular weight of 11.7 kDa and an isoelectric point of 5.03. PxTrx was mainly expressed in larval Malpighian tubules and the fat body. An enriched recombinant PxTrx had insulin disulphide reductase activity and stimulated Human Embryonic Kidney 293 (HEK293) cell proliferation. It also protected supercoiled DNA and living HEK293 cells from H 2 O 2 -induced damage. Parasitization by Cotesia vestalis and injections of 0.05 and 0.01 equivalents of C. vestalis Bracovirus (CvBv), the symbiotic virus carried by the parasitoid, led to down-regulation of PxTrx expression in host fat body. Taken together, our results indicate that PxTrx contributes to the maintenance of P. xylostella cellular haemostasis. Host fat body expression of PxTrx is strongly attenuated by parasitization and by injections of CvBv. © 2016 The Royal Entomological Society.

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...

Assembly of the 30S subunit from Escherichia coli ribosomes occurs via two assembly domains which are initiated by S4 and S7

International Nuclear Information System (INIS)

Nowotny, V.; Nierhaus, K.H.

1988-01-01

A protein which initiates assembly of ribosomes is defined as a protein which binds to the respective rRNA without cooperativity (i.e., without the help of other proteins) during the onset of assembly and is essential for the formation of active ribosomal subunits. The number of proteins binding without cooperativity was determined by monitoring the reconstitution output of active particles at various inputs of 16S rRNA, in the present of constant amounts of 30S-derived proteins (TP30): This showed that only two of the proteins of the 30S subunit are assembly-initiator proteins. These two proteins are still present on a LiCl core particle comprising 16S rRNA and 12 proteins (including minor proteins). The 12 proteins were isolated, and a series of reconstitution experiments at various levels of rRNA excess demonstrated that S4 and S7 are the initiator proteins. Pulse-chase experiments performed during the early assembly with 14 C- and 3 H-labeled TP30 and the determination of the 14 C/ 3 H ratio of the individual proteins within the assembled particles revealed a bilobal structure of the 30S assembly: A group of six proteins headed by S4 (namely, S4, S20, S16, S15, S6, and S18) resisted the chasing most efficiently (S4 assembly domain). None of the proteins depending on S7 during assembly were found in this group but rather in a second group with intermediate chasing stability [S7 assembly domain; consisting of S7, S9, (S8), S19, and S3]. A number of proteins could be fully chased during the early assembly and therefore represent late assembly proteins (S10, S5, S13, S2, S21, S1). These findings fit well with the 30S assembly map. These data, together with the assembly map, imply that S8 and S5 play an important role in the interconnection of the two assembly domains

Improving the performance of DomainDiscovery of protein domain boundary assignment using inter-domain linker index

Directory of Open Access Journals (Sweden)

Zomaya Albert Y

2006-12-01

Full Text Available Abstract Background Knowledge of protein domain boundaries is critical for the characterisation and understanding of protein function. The ability to identify domains without the knowledge of the structure – by using sequence information only – is an essential step in many types of protein analyses. In this present study, we demonstrate that the performance of DomainDiscovery is improved significantly by including the inter-domain linker index value for domain identification from sequence-based information. Improved DomainDiscovery uses a Support Vector Machine (SVM approach and a unique training dataset built on the principle of consensus among experts in defining domains in protein structure. The SVM was trained using a PSSM (Position Specific Scoring Matrix, secondary structure, solvent accessibility information and inter-domain linker index to detect possible domain boundaries for a target sequence. Results Improved DomainDiscovery is compared with other methods by benchmarking against a structurally non-redundant dataset and also CASP5 targets. Improved DomainDiscovery achieves 70% accuracy for domain boundary identification in multi-domains proteins. Conclusion Improved DomainDiscovery compares favourably to the performance of other methods and excels in the identification of domain boundaries for multi-domain proteins as a result of introducing support vector machine with benchmark_2 dataset.

Common Altered Epigenomic Domains in Cancer Cells: Characterization and Subtle Variations

International Nuclear Information System (INIS)

Tsai, Yi-Chien; Chiao, Chun-Hui; Chang, Ian Yi-Feng; Chen, Dow-Tien; Liu, Tze-Tze; Hua, Kate; Chang, Chuan-Hsiung; Hsu, Ming-Ta

2011-01-01

We have previously identified large megabase-sized hypomethylated zones in the genome of the breast cancer cell line MCF-7 using the TspRI-ExoIII technique. In this report, we used a more convenient high throughput method for mapping the hypomethylated zones in a number of human tumor genomes simultaneously. The method was validated by the bisulfite sequencing of 39 randomly chosen sites in a demethylated domain and by bisulfite genome-wide sequencing of the MCF-7 genome. This showed that the genomes of the various tumor cell lines, as well as some primary tumors, exhibit common hypomethylated domains. Interestingly, these hypomethylated domains are correlated with low CpG density distribution genome-wide, together with the histone H3K27Me3 landscape. Furthermore, they are inversely correlated with the H3K9Ac landscape and gene expression as measured in MCF-7 cells. Treatment with drugs resulted in en-bloc changes to the methylation domains. A close examination of the methylation domains found differences between non-invasive and invasive tumors with respect to tumorigenesis related genes. Taken together these results suggest that the human genome is organized in epigenomic domains that contain various different types of genes and imply that there are cis- and trans-regulators that control these domain-wide epigenetic changes and hence gene expression in the human genome. The hypomethylated domains are located in gene deserts that contain mainly tissue-specific genes and therefore we hypothesize that tumor cells keep these regions demethylated and silenced in order to save energy and resources and allow higher levels of cell proliferation and better survival (a thrifty tumor genome hypothesis)

Insight into the Mode of Action of Celangulin V on the Transmembrane Potential of Midgut Cells in Lepidopteran Larvae

Directory of Open Access Journals (Sweden)

Yingying Wang

2017-12-01

Full Text Available Celangulin V (CV is the main insecticidal constituent of Celastrus angulatus. The V-ATPase H subunit of the midgut cells of lepidopteran larvae is the putative target protein of CV. Here, we compared the effects of CV on the midgut membrane potentials of Mythimna separata and Agrotis ipsilon larvae with those of the Cry1Ab toxin from Bacillus thuringiensis and with those of inactive CV-MIA, a synthetic derivative of CV. We investigated the changes in the apical membrane potentials (Vam and basolateral membrane potentials (Vbm of the midguts of sixth-instar larvae force-fed with the test toxins. We also measured the Vam and Vbm of larval midguts that were directly incubated with the test toxins. Similar to the effect of Cry1Ab, the Vam of CV-treated midguts rapidly decayed over time in a dose-dependent manner. By contrast, CV-MIA did not influence Vam. Meanwhile, the Vam of A. ipsilon larval midguts directly incubated with CV decayed less than that of M. separata larval midguts, whereas that of larvae force-fed with CV did not significantly change. Similar to Cry1Ab, CV did not affect the Vbm of isolated midguts. CV significantly inhibited V-ATPase activity in a dose-dependent manner. Therefore, CV initially inhibits V-ATPase in the apical membrane and affects intracellular pH, homeostasis, and nutrient transport mechanisms in lepidopteran midgut cells.

Continuous stroke unit electrocardiographic monitoring versus 24-hour Holter electrocardiography for detection of paroxysmal atrial fibrillation after stroke.

Science.gov (United States)

Rizos, Timolaos; Güntner, Janina; Jenetzky, Ekkehart; Marquardt, Lars; Reichardt, Christine; Becker, Rüdiger; Reinhardt, Roland; Hepp, Thomas; Kirchhof, Paulus; Aleynichenko, Elena; Ringleb, Peter; Hacke, Werner; Veltkamp, Roland

2012-10-01

Cardioembolism in paroxysmal atrial fibrillation (pxAF) is a frequent cause of ischemic stroke. Sensitive detection of pxAF after stroke is crucial for adequate secondary stroke prevention; the optimal diagnostic modality to detect pxAF on stroke units is unknown. We compared 24-hour Holter electrocardiography (ECG) with continuous stroke unit ECG monitoring (CEM) for pxAF detection. Patients with acute ischemic stroke or transient ischemic attack were prospectively enrolled. After a 12-channel ECG on admission, all patients received 24-hour Holter ECG and CEM. Additionally, ECG monitoring data underwent automated analysis using dedicated software to identify pxAF. Patients with a history of atrial fibrillation or with atrial fibrillation on the admission ECG were excluded. Four hundred ninety-six patients (median age, 69 years; 61.5% male) fulfilled all inclusion criteria (ischemic stroke: 80.4%; transient ischemic attack: 19.6%). Median stroke unit stay lasted 88.8 hours (interquartile range, 65.0-122.0). ECG data for automated CEM analysis were available for a median time of 64.0 hours (43.0-89.8). Paroxysmal AF was documented in 41 of 496 patients (8.3%). Of these, Holter detected pxAF in 34.1%; CEM in 65.9%; and automated CEM in 92.7%. CEM and automated CEM detected significantly more patients with pxAF than Holter (Pstroke on stroke units compared with 24-hour Holter ECG. The comparative usefulness of prolonged or repetitive Holter ECG recordings requires further evaluation.

Impaired insulin-stimulated nonoxidative glucose metabolism in pancreas-kidney transplant recipients

DEFF Research Database (Denmark)

Christiansen, Erik; Vestergaard, Henrik; Tibell, Annika

1996-01-01

-response curve for glucose disposal rates (Rd) was shifted to the right in the Px and Kx groups, and the maximal glucose disposal rate was reduced by 40% in the Px group (11.7 +/- 1.1 mg.kg-1 fat-free mass.min-1) and 30% in the Kx group (13.9 +/- 1.2 mg.kg-1 fat-free mass.min-1) compared with that in control...

ON A NUMERICAL ALGORITHM FOR UNCERTAIN SYSTEM ∫ Φ ...

African Journals Online (AJOL)

Administrator

Science World Journal Vol 7 (No 1) 2012 www.scienceworldjournal.org. ISSN 1597-6343. On a Numerical Algorithm for Uncertain System. Newton's Algorithm. Step 1 Calculate. )(),().(k k k. xAxgxF. Step 2. Check if ε. <. )(k xg for a predetermined ,ε if so stop, else. Step3. Set k k. PxA. )( = )(k xg. -. Step4. Set k k k. Px x. +. = +1.

Impaired insulin-stimulated nonoxidative glucose metabolism in pancreas-kidney transplant recipients. Dose-response effects of insulin on glucose turnover

DEFF Research Database (Denmark)

Christiansen, E; Vestergaard, H; Tibell, A

1996-01-01

-response curve for glucose disposal rates (Rd) was shifted to the right in the Px and Kx groups, and the maximal glucose disposal rate was reduced by 40% in the Px group (11.7 +/- 1.1 mg.kg-1 fat-free mass.min-1) and 30% in the Kx group (13.9 +/- 1.2 mg.kg-1 fat-free mass.min-1) compared with that in control...

Polarized Epithermal Neutron Studies of Magnetic Domains

International Nuclear Information System (INIS)

Alfimenkov, V.P.; Chernikov, A.N.; Lason, L.; Mareev, Yu. D.; Novitsky, V.V.; Pikelner, L.B.; Skoy, V.R.; Tsulaya, M.I.; Gould, C.R.; Haase, D.G.; Roberson, N.R.

1997-01-01

The average size and shape of magnetic domains in a material can be determined from the precession of polarized neutrons traversing the material. Epithermal neutrons (0.5eV< En<100eV), which process more slowly than thermals, effectively probe the internal structure of samples that are thick or have large domains or large internal fields. Such epithermal neutron measurements require a neutron polarizer and analyzer based on cryogenically polarized spin filters. We discuss the measurements at JINR, Dubna, of magnetic domains in a 2.0 cm. diam. crystal of holmium using 1.7 to 59eV neutrons polarized by a dynamically polarized proton target and analyzed with a statically polarized dysprosium target

Nucleation of domains under the influence of temperature in ...

Indian Academy of Sciences (India)

Abstract. It is found that the nucleation of domains can take place in Ba5Ti2O7Cl4 under the influence of temperature unlike in many other ferroelectrics. The nucleated domain can also be removed from the structure under the randomizing effect of tem- perature. These observations have been explained on the basis of a ...

S1 constrains S4 in the voltage sensor domain of Kv7.1 K+ channels.

Directory of Open Access Journals (Sweden)

Yoni Haitin

Full Text Available Voltage-gated K(+ channels comprise a central pore enclosed by four voltage-sensing domains (VSDs. While movement of the S4 helix is known to couple to channel gate opening and closing, the nature of S4 motion is unclear. Here, we substituted S4 residues of Kv7.1 channels by cysteine and recorded whole-cell mutant channel currents in Xenopus oocytes using the two-electrode voltage-clamp technique. In the closed state, disulfide and metal bridges constrain residue S225 (S4 nearby C136 (S1 within the same VSD. In the open state, two neighboring I227 (S4 are constrained at proximity while residue R228 (S4 is confined close to C136 (S1 of an adjacent VSD. Structural modeling predicts that in the closed to open transition, an axial rotation (approximately 190 degrees and outward translation of S4 (approximately 12 A is accompanied by VSD rocking. This large sensor motion changes the intra-VSD S1-S4 interaction to an inter-VSD S1-S4 interaction. These constraints provide a ground for cooperative subunit interactions and suggest a key role of the S1 segment in steering S4 motion during Kv7.1 gating.

FY1995 ultrafast photonic devices using dielectric domain superlattice; 1995 nendo yudentai domain chokoshi wo mochiita chokosoku photonic device

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-31

All optical wavelength conversion around 1550nm is of great importance for the wavelength division multiplexing optical communication system. A dielectric domain superlattice, which has a periodically domain inverted structure, has a wide potential for the various nonlinear interactions such as second harmonic generation (SHG) and difference frequency generation (DFG). The purpose of our research is to establish the theoretical bases and fabrication processes of the guided-wave wavelength converter based on the DFG by domain-inverted LiTaO{sub 3}. We have investigated basic characteristics of guided-wave DFG devices and developed the domain-inversion process by an electric field poling utilizing a liquid electrolyte consisting of LiCI in deionized water as a electrode for applying the electric field to LiTaO{sub 3} substrate. By controlling the injection current for the domain inversion precisely, we fabricated successfully uniform domain-inverted structures. 0.5mm-thick domain-inverted LiTaO{sub 3} of 7.8, 17.2 and 21.3 {mu}m periods and 0.5 duty ratio were obtained by optimizing electrode structure and the domain-inversion process. Waveguide structures can increase the conversion efficiency of DFG by several orders of magnitude over bulk interactions. We have also developed waveguide fabrication process for the domain-inverted LiTaO{sub 3} substrate. Low loss proton-exchanged waveguides were formed by annealed proton exchange technique without a degradation of the domain inversion structure. Domain-controlled nonlinear optics by designing the ferroelectric domain structure of LiTaO{sub 3} and LiNbO{sub 3} make it possible to extend all the spectral range from ultra-violet to far-infrared and THz wave region. (NEDO)

The Bayesian Approach to Association

Science.gov (United States)

Arora, N. S.

2017-12-01

The Bayesian approach to Association focuses mainly on quantifying the physics of the domain. In the case of seismic association for instance let X be the set of all significant events (above some threshold) and their attributes, such as location, time, and magnitude, Y1 be the set of detections that are caused by significant events and their attributes such as seismic phase, arrival time, amplitude etc., Y2 be the set of detections that are not caused by significant events, and finally Y be the set of observed detections We would now define the joint distribution P(X, Y1, Y2, Y) = P(X) P(Y1 | X) P(Y2) I(Y = Y1 + Y2) ; where the last term simply states that Y1 and Y2 are a partitioning of Y. Given the above joint distribution the inference problem is simply to find the X, Y1, and Y2 that maximizes posterior probability P(X, Y1, Y2| Y) which reduces to maximizing P(X) P(Y1 | X) P(Y2) I(Y = Y1 + Y2). In this expression P(X) captures our prior belief about event locations. P(Y1 | X) captures notions of travel time, residual error distributions as well as detection and mis-detection probabilities. While P(Y2) captures the false detection rate of our seismic network. The elegance of this approach is that all of the assumptions are stated clearly in the model for P(X), P(Y1|X) and P(Y2). The implementation of the inference is merely a by-product of this model. In contrast some of the other methods such as GA hide a number of assumptions in the implementation details of the inference - such as the so called "driver cells." The other important aspect of this approach is that all seismic knowledge including knowledge from other domains such as infrasound and hydroacoustic can be included in the same model. So, we don't need to separately account for misdetections or merge seismic and infrasound events as a separate step. Finally, it should be noted that the objective of automatic association is to simplify the job of humans who are publishing seismic bulletins based on this

Structural domain walls in polar hexagonal manganites

Science.gov (United States)

Kumagai, Yu

2014-03-01

The domain structure in the multiferroic hexagonal manganites is currently intensely investigated, motivated by the observation of intriguing sixfold topological defects at their meeting points [Choi, T. et al,. Nature Mater. 9, 253 (2010).] and nanoscale electrical conductivity at the domain walls [Wu, W. et al., Phys. Rev. Lett. 108, 077203 (2012).; Meier, D. et al., Nature Mater. 11, 284 (2012).], as well as reports of coupling between ferroelectricity, magnetism and structural antiphase domains [Geng, Y. et al., Nano Lett. 12, 6055 (2012).]. The detailed structure of the domain walls, as well as the origin of such couplings, however, was previously not fully understood. In the present study, we have used first-principles density functional theory to calculate the structure and properties of the low-energy structural domain walls in the hexagonal manganites [Kumagai, Y. and Spaldin, N. A., Nature Commun. 4, 1540 (2013).]. We find that the lowest energy domain walls are atomically sharp, with {210}orientation, explaining the orientation of recently observed stripe domains and suggesting their topological protection [Chae, S. C. et al., Phys. Rev. Lett. 108, 167603 (2012).]. We also explain why ferroelectric domain walls are always simultaneously antiphase walls, propose a mechanism for ferroelectric switching through domain-wall motion, and suggest an atomistic structure for the cores of the sixfold topological defects. This work was supported by ETH Zurich, the European Research Council FP7 Advanced Grants program me (grant number 291151), the JSPS Postdoctoral Fellowships for Research Abroad, and the MEXT Elements Strategy Initiative to Form Core Research Center TIES.

Volumetric adsorptive microsampling-liquid chromatography tandem mass spectrometry assay for the simultaneous quantification of four antibiotics in human blood: Method development, validation and comparison with dried blood spot.

Science.gov (United States)

Barco, Sebastiano; Castagnola, Elio; Moscatelli, Andrea; Rudge, James; Tripodi, Gino; Cangemi, Giuliana

2017-10-25

In this paper we show the development and validation of a volumetric absorptive microsampling (VAMS™)-LC-MS/MS method for the simultaneous quantification of four antibiotics: piperacillin-tazobactam, meropenem, linezolid and ceftazidime in 10μL human blood. The novel VAMS-LC-MS/MS method has been compared with a dried blood spot (DBS)-based method in terms of impact of hematocrit (HCT) on accuracy, reproducibility, recovery and matrix effect. Antibiotics were extracted from VAMS and DBS by protein precipitation with methanol after a re-hydration step at 37°C for 10min. LC-MS/MS was carried out on a Thermo Scientific™ TSQ Quantum™ Access MAX triple quadrupole coupled to an Accela ™UHPLC system. The VAMS-LC-MS/MS method is selective, precise and reproducible. In contrast to DBS, it allows an accurate quantification without any HCT influence. It has been applied to samples derived from pediatric patients under therapy. VAMS is a valid alternative sampling strategy for the quantification of antibiotics and is valuable in support of clinical PK/PD studies and consequently therapeutic drug monitoring (TDM) in pediatrics. Copyright © 2017 Elsevier B.V. All rights reserved.

Energy engineering. Standardization in the domain of coldness production; Genie energetique. Normalisation dans le domaine du froid

Energy Technology Data Exchange (ETDEWEB)

Legent, N. [Association Francaise de Normalisation (AFNOR), 92 - Paris-la-Defense (France)

2000-10-01

This paper deals with the recent advances in the domain of standardization and regulation of refrigeration and cold production systems used in the industry and in the commercial sector: 1 - international standardization; 2 - European standardization; 3 - international standardization in the domain of cold production (ISO/TC 86 'coldness and air conditioning', CEI 61C 'domestic refrigerating appliances', CEI 61D 'air-conditioning appliances for domestic and similar use', ISO/TC 104 'goods transportation containers'); 4 - European standardization in the domain of cold production (CEN/TC 182 'refrigerating systems - safety and environment requirements', CEN/TC 44 'household refrigerating appliances and refrigerating furniture for stores', CEN/TC 113 'heat pumps and air-conditioners', CEN/TC 141 'manometers and thermometers, measuring and recording means', CENELEC 61 'safety of domestic electrical appliances'); 5 - French standardization (international file, European file, French file, French standardization system); 6 - national standardization in other countries; 7 - regulations in the domain of cold production. (J.S.)

Polarized epithermal neutron studies of magnetic domains

International Nuclear Information System (INIS)

Alfimenkov, V.P.; Chernikov, A.N.; Lason, L.; Mareev, Y.D.; Novitsky, V.V.; Pikelner, L.B.; Skoy, V.R.; Tsulaya, M.I.; Gould, C.R.; Haase, D.G.; the Triangle Universities Nuclear Laboratory, Durham, North Carolina; Roberson, N.R.; the Triangle Universities Nuclear Laboratory, Durham, North Carolina

1997-01-01

The average size and shape of magnetic domains in a material can be determined from the precession of polarized neutrons traversing the material. Epithermal neutrons (0.5eV n <100eV), which precess more slowly than thermals, effectively probe the internal structure of samples that are thick or have large domains or large internal fields. Such epithermal neutron measurements require a neutron polarizer and analyzer based on cryogenically polarized spin filters. We discuss the measurement at JINR, Dubna, of magnetic domains in a 2.0 cm. diam. crystal of holmium using 1.7 to 59 eV neutrons polarized by a dynamically polarized proton target and analyzed with a statically polarized dysprosium target. copyright 1997 American Institute of Physics

Gender Differences in the Domain-Specific Contributions to Moderate-to-Vigorous Physical Activity, Accessed by GPS

DEFF Research Database (Denmark)

Pizarro, Andreia Nogueira; Schipperijn, Jasper; Ribeiro, José Carlos

2017-01-01

time in school (37.0%) and leisure (24.9%) than girls (24.7% and 18.1, respectively).Conclusions:Interventions to increase transport behavior may be relevant for children?s MVPA. School is an important domain for boys PA, while for girls increasing the supportiveness of the school environment for PA...... children (201 girls; X=11.7y) wore an accelerometer and a GPS for 7 days. PALMS software combined data, categorized non-sedentary time and bouts of moderate-to-vigorous physical activity (MVPA). Geographical information system allocated activity into 4 domains: school, leisure, transport and home.......Results:Overall, a higher proportion of time in MVPA was found in the transport domain (45.5%), school (30.5%), leisure (21.3%) and home (2.7%). Gender differences were found for the proportion of time spent across domains. Girls (54.5%) had more MVPA than boys (35.2%) in the transport domain, whereas boys spent more MVPA...

The Effect of Paroxetine on Ouabain-Induced Toxicity in Isolated Guinea Pig Atria

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Farzaneh Najar

2011-04-01

Full Text Available It has been reported that selective serotonin reuptake inhibitors (SSRIs possess some cardiac effects. In the present study we have investigated the effect of paroxetine (PX, a potent SSRI agent, on spontaneously as well as ouabain-induced arrhythmia beating isolated guinea-pig atria. The Guinea-pig heart was rapidly removed; the auricles were dissected out in oxygenated modified Krebs solution. The rate and force of spontaneous contractions were recorded isometrically with a photosensitive transducer. PX (1-16 µg/ml caused a dose-dependent decrease in the rate of contractions (14-70% and contractile force (8-16%. Ouabain alone (1.2 µg/ml produced arrhythmia at 7.2 ± 1.5 min and asystole at 20.1 ± 3.1 min. Pretreatment with PX (4 µg/ml significantly increased the time of arrhythmia onset to 19.8 min. In addition, PX prolonged the duration of action beating from 20.1 ± 3.1 min to 43.1± 2.6 and delayed the occurrence of asystole. The pattern of contractile force by PX + ouabain treatment was more regular than that observed after administration of ouabain alone. The above findings may the probably be due to the inhibition of cardiac Na+ and Ca2+ channels or autonomic nervous system. Results also suggest that PX may reduce the membrane conductance through inhibition of ionic channels to prevent ouabain-induced arrhythmia.

Polybrominated diphenyl ether (PBDE)-induced alterations in vitamin A and thyroid hormone concentrations in the rat during lactation and early postnatal development

International Nuclear Information System (INIS)

Ellis-Hutchings, Robert G.; Cherr, Gary N.; Hanna, Lynn A.; Keen, Carl L.

2006-01-01

In experimental animals fed standard laboratory diets, penta-BDE mixtures can decrease circulating thyroid hormone and liver vitamin A concentrations. A substantial number of pregnant women and their children have marginal vitamin A status, potentially increasing their risk of adverse effects to penta-BDE exposure. The current study investigated the effects of maternal gestational and lactational penta-BDE exposure on thyroid hormone and vitamin A homeostasis in rats of sufficient vitamin A (VAS) or marginal vitamin A (VAM) status and their offspring. Dams were administered daily oral doses of 18 mg/kg DE-71 (a penta-BDE mixture) or a corn oil vehicle from gestation day 6 through lactation day (LD) 18. Thyroid hormone and vitamin A homeostasis were assessed in plasma and tissues of LD 19 dams and postnatal day (PND) 12, 18, and 31 pups. DE-71 exposure induced hepatomegaly in VAS and VAM pups at all timepoints and increased testes weights at PND 31. While liver vitamin A concentrations were low in DE-71 treated dams and pups, plasma retinol concentrations and plasma retinol binding protein levels were only low in VAM animals exposed to DE-71. DE-71 exposure lowered plasma thyroxine concentrations in VAS and VAM dams and pups. Plasma thyroid stimulating hormone concentrations were high in VAM dams exposed to DE-71, suggesting that marginal vitamin A status enhances the susceptibility to thyroid hormone axis disruption by DE-71. These results support the concept that marginal vitamin A status in pregnant women may increase the risk for PBDE-induced disruptions in vitamin A and thyroid hormone homeostasis

Repeated high-speed activities during youth soccer games in relation to changes in maximal sprinting and aerobic speeds.

Science.gov (United States)

Buchheit, M; Simpson, B M; Mendez-Villanueva, A

2013-01-01

The aim of this study was to examine in highly-trained young soccer players whether substantial changes in either maximal sprinting speed (MSS) or maximal aerobic speed (as inferred from peak incremental test speed, V(Vam-Eval)) can affect repeated high-intensity running during games. Data from 33 players (14.5±1.3 years), who presented substantial changes in either MSS or V(Vam-Eval) throughout 2 consecutive testing periods (~3 months) were included in the final analysis. For each player, time-motion analyses were performed using a global positioning system (1-Hz) during 2-10 international club games played within 1-2 months from/to each testing period of interest (n for game analyzed=109, player-games=393, games per player per period=4±2). Sprint activities were defined as at least a 1-s run at intensities higher than 61% of individual MSS. Repeated-sprint sequences (RSS) were defined as a minimum of 2 consecutive sprints interspersed with a maximum of 60 s of recovery. Improvements in both MSS and V(Vam-Eval) were likely associated with a decreased RSS occurrence, but in some positions only (e. g., - 24% vs. - 3% for improvements in MSS in strikers vs. midfielders, respectively). The changes in the number of sprints per RSS were less clear but also position-dependent, e. g., +7 to +12% for full-backs and wingers, - 5 to - 7% for centre-backs and midfielders. In developing soccer players, changes in repeated-sprint activity during games do not necessarily match those in physical fitness. Game tactical and strategic requirements are likely to modulate on-field players' activity patterns independently (at least partially) of players' physical capacities. © Georg Thieme Verlag KG Stuttgart · New York.

Llama Single Domain Antibodies Specific for the 7 Botulinum Neurotoxin Serotypes as Heptaplex Immunoreagents

Science.gov (United States)

Collazo, M. Thelma; Garza, John A.; Hayhurst, Andrew

2010-01-01

Background There are currently 7 known serotypes of botulinum neurotoxin (BoNT) classified upon non-cross reactivity of neutralizing immunoglobulins. Non-neutralizing immunoglobulins, however, can exhibit cross-reactivities between 2 or more serotypes, particularly mosaic forms, which can hamper the development of highly specific immunoassays, especially if based on polyclonal antisera. Here we employ facile recombinant antibody technology to subtractively select ligands to each of the 7 BoNT serotypes, resulting in populations with very high specificity for their intended serotype. Methods and Findings A single llama was immunized with a cocktail of 7 BoNT toxoids to generate a phage display library of single domain antibodies (sdAb, VHH or nanobodies) which were selected on live toxins. Resulting sdAb were capable of detecting both toxin and toxin complex with the best combinations able to detect 100s-10s of pg per 50 µL sample in a liquid bead array. The most sensitive sdAb were combined in a heptaplex assay to identify each of the BoNT serotypes in buffer and milk and to a lesser extent in carrot juice, orange juice and cola. Several anti-A(1) sdAb recognized A2 complex, showing that subtype cross-reactivity within a serotype was evident. Many of our sdAb could act as both captor and tracer for several toxin and toxin complexes suggesting sdAb can be used as architectural probes to indicate BoNT oligomerisation. Six of 14 anti-A clones exhibited inhibition of SNAP-25 cleavage in the neuro-2A assay indicating some sdAb had toxin neutralizing capabilities. Many sdAb were also shown to be refoldable after exposure to high temperatures in contrast to polyclonal antisera, as monitored by circular dichroism. Conclusions Our panel of molecularly flexible antibodies should not only serve as a good starting point for ruggedizing assays and inhibitors, but enable the intricate architectures of BoNT toxins and complexes to be probed more extensively. PMID:20098614

The 1.7 Å X-ray crystal structure of the porcine factor VIII C2 domain and binding analysis to anti-human C2 domain antibodies and phospholipid surfaces.

Directory of Open Access Journals (Sweden)

Caileen M Brison

Full Text Available The factor VIII C2 domain is essential for binding to activated platelet surfaces as well as the cofactor activity of factor VIII in blood coagulation. Inhibitory antibodies against the C2 domain commonly develop following factor VIII replacement therapy for hemophilia A patients, or they may spontaneously arise in cases of acquired hemophilia. Porcine factor VIII is an effective therapeutic for hemophilia patients with inhibitor due to its low cross-reactivity; however, the molecular basis for this behavior is poorly understood. In this study, the X-ray crystal structure of the porcine factor VIII C2 domain was determined, and superposition of the human and porcine C2 domains demonstrates that most surface-exposed differences cluster on the face harboring the "non-classical" antibody epitopes. Furthermore, antibody-binding results illustrate that the "classical" 3E6 antibody can bind both the human and porcine C2 domains, although the inhibitory titer to human factor VIII is 41 Bethesda Units (BU/mg IgG versus 0.8 BU/mg IgG to porcine factor VIII, while the non-classical G99 antibody does not bind to the porcine C2 domain nor inhibit porcine factor VIII activity. Further structural analysis of differences between the electrostatic surface potentials suggest that the C2 domain binds to the negatively charged phospholipid surfaces of activated platelets primarily through the 3E6 epitope region. In contrast, the G99 face, which contains residue 2227, should be distal to the membrane surface. Phospholipid binding assays indicate that both porcine and human factor VIII C2 domains bind with comparable affinities, and the human K2227A and K2227E mutants bind to phospholipid surfaces with similar affinities as well. Lastly, the G99 IgG bound to PS-immobilized factor VIII C2 domain with an apparent dissociation constant of 15.5 nM, whereas 3E6 antibody binding to PS-bound C2 domain was not observed.

Vesicular-arbuscular mycorrhizal populations in stored topsoil

Energy Technology Data Exchange (ETDEWEB)

Harris, J.A.; Hunter, D.; Birch, P.; Short, K.C. (North East London Polytechnic, London (UK). Environment and Industry Research Unit, Dept. of Biology and Biochemistry)

1987-01-01

Two soil stores of different ages were sampled to investigate their vesicular-arbuscular mycorrhizal (VAM) populations. The soils collected were assessed for pH, moisture content, loss on ignition, spore numbers, number and size of root fragments present and percentage of these roots infected with VAM. A corn-root bioassay was used to determine soil infectivity. Root fragment number, size, % root infection and soil infectivity were negatively correlated with soil depth. VAM spore number was not significantly correlated with depth in either store. It appears that infected root fragments and fresh roots were the source of inoculum although there may have been a contribution from spores in the younger store. The infectivity of the older store soil was less than that of the younger store. 12 refs., 5 tabs.

Increased sporulation of vesicular-arbuscular mycorrhizal fungi by manipulation of nutrient regimens.

Science.gov (United States)

Douds, D D; Schenck, N C

1990-02-01

Adjustment of pot culture nutrient solutions increased root colonization and sporulation of vesicular-arbuscular mycorrhizal (VAM) fungi. Paspalum notatum Flugge and VAM fungi were grown in a sandy soil low in N and available P. Hoagland nutrient solution without P enhanced sporulation in soil and root colonization of Acaulospora longula, Scutellospora heterogama, Gigaspora margarita, and a wide range of other VAM fungi over levels produced by a tap water control or nutrient solutions containing P. However, Glomus intraradices produced significantly more spores in plant roots in the tap water control treatment. The effect of the nutrient solutions was not due solely to N nutrition, because the addition of NH(4)NO(3) decreased both colonization and sporulation by G. margarita relative to levels produced by Hoagland solution without P.

Phase Behavior and Domain Size in Sphingomyelin-Containing Lipid Bilayers

Science.gov (United States)

Petruzielo, Robin S.; Heberle, Frederick A.; Drazba, Paul; Katsaras, John; Feigenson, Gerald W.

2013-01-01

Membrane raft size measurements are crucial to understanding the stability and functionality of rafts in cells. The challenge of accurately measuring raft size is evidenced by the disparate reports of domain sizes, which range from nanometers to microns for the ternary model membrane system sphingomyelin (SM)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/cholesterol (Chol). Using Förster resonance energy transfer (FRET) and differential scanning calorimetry (DSC), we established phase diagrams for porcine brain SM (bSM)/dioleoyl-sn-glycero-3-phosphocholine (DOPC)/Chol and bSM/POPC/Chol at 15 and 25°C. By combining two techniques with different spatial sensitivities, namely FRET and small-angle neutron scattering (SANS), we have significantly narrowed the uncertainty in domain size estimates for bSM/POPC/Chol mixtures. Compositional trends in FRET data revealed coexisting domains at 15 and 25°C for both mixtures, while SANS measurements detected no domain formation for bSM/POPC/Chol. Together these results indicate that liquid domains in bSM/POPC/Chol are between 2 and 7 nm in radius at 25°C: that is, domains must be on the order of the 2–6 nm Förster distance of the FRET probes, but smaller than the ~7 nm minimum cluster size detectable with SANS. However, for palmitoyl SM (PSM)/POPC/Chol at a similar composition, SANS detected coexisting liquid domains. This increase in domain size upon replacing the natural SM component (which consists of a mixture of chain lengths) with synthetic PSM, suggests a role for SM chain length in modulating raft size in vivo. PMID:23337475

Whirlin and PDZ domain-containing 7 (PDZD7) proteins are both required to form the quaternary protein complex associated with Usher syndrome type 2.

Science.gov (United States)

Chen, Qian; Zou, Junhuang; Shen, Zuolian; Zhang, Weiping; Yang, Jun

2014-12-26

Usher syndrome (USH) is the leading genetic cause of combined hearing and vision loss. Among the three USH clinical types, type 2 (USH2) occurs most commonly. USH2A, GPR98, and WHRN are three known causative genes of USH2, whereas PDZD7 is a modifier gene found in USH2 patients. The proteins encoded by these four USH genes have been proposed to form a multiprotein complex, the USH2 complex, due to interactions found among some of these proteins in vitro, their colocalization in vivo, and mutual dependence of some of these proteins for their normal in vivo localizations. However, evidence showing the formation of the USH2 complex is missing, and details on how this complex is formed remain elusive. Here, we systematically investigated interactions among the intracellular regions of the four USH proteins using colocalization, yeast two-hybrid, and pull-down assays. We show that multiple domains of the four USH proteins interact among one another. Importantly, both WHRN and PDZD7 are required for the complex formation with USH2A and GPR98. In this USH2 quaternary complex, WHRN prefers to bind to USH2A, whereas PDZD7 prefers to bind to GPR98. Interaction between WHRN and PDZD7 is the bridge between USH2A and GPR98. Additionally, the USH2 quaternary complex has a variable stoichiometry. These findings suggest that a non-obligate, short term, and dynamic USH2 quaternary protein complex may exist in vivo. Our work provides valuable insight into the physiological role of the USH2 complex in vivo and informs possible reconstruction of the USH2 complex for future therapy. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Measurement of Nonribosomal Peptide Synthetase Adenylation Domain Activity Using a Continuous Hydroxylamine Release Assay.

Science.gov (United States)

Duckworth, Benjamin P; Wilson, Daniel J; Aldrich, Courtney C

2016-01-01

Adenylation is a crucial enzymatic process in the biosynthesis of nonribosomal peptide synthetase (NRPS) derived natural products. Adenylation domains are considered the gatekeepers of NRPSs since they select, activate, and load the carboxylic acid substrate onto a downstream peptidyl carrier protein (PCP) domain of the NRPS. We describe a coupled continuous kinetic assay for NRPS adenylation domains that substitutes the PCP domain with hydroxylamine as the acceptor molecule. The pyrophosphate released from the first-half reaction is then measured using a two-enzyme coupling system, which detects conversion of the chromogenic substrate 7-methylthioguanosine (MesG) to 7-methylthioguanine. From profiling substrate specificity of unknown or engineered adenylation domains to studying chemical inhibition of adenylating enzymes, this robust assay will be of widespread utility in the broad field NRPS enzymology.

Llama-derived single variable domains (nanobodies) directed against chemokine receptor CXCR7 reduce head and neck cancer cell growth in vivo.

Science.gov (United States)

Maussang, David; Mujić-Delić, Azra; Descamps, Francis J; Stortelers, Catelijne; Vanlandschoot, Peter; Stigter-van Walsum, Marijke; Vischer, Henry F; van Roy, Maarten; Vosjan, Maria; Gonzalez-Pajuelo, Maria; van Dongen, Guus A M S; Merchiers, Pascal; van Rompaey, Philippe; Smit, Martine J

2013-10-11

The chemokine receptor CXCR7, belonging to the membrane-bound G protein-coupled receptor superfamily, is expressed in several tumor types. Inhibition of CXCR7 with either small molecules or small interference (si)RNA has shown promising therapeutic benefits in several tumor models. With the increased interest and effectiveness of biologicals inhibiting membrane-bound receptors we made use of the "Nanobody platform" to target CXCR7. Previously we showed that Nanobodies, i.e. immunoglobulin single variable domains derived from naturally occurring heavy chain-only camelids antibodies, represent new biological tools to efficiently tackle difficult drug targets such as G protein-coupled receptors. In this study we developed and characterized highly selective and potent Nanobodies against CXCR7. Interestingly, the CXCR7-targeting Nanobodies displayed antagonistic properties in contrast with previously reported CXCR7-targeting agents. Several high affinity CXCR7-specific Nanobodies potently inhibited CXCL12-induced β-arrestin2 recruitment in vitro. A wide variety of tumor biopsies was profiled, showing for the first time high expression of CXCR7 in head and neck cancer. Using a patient-derived CXCR7-expressing head and neck cancer xenograft model in nude mice, tumor growth was inhibited by CXCR7-targeting Nanobody therapy. Mechanistically, CXCR7-targeting Nanobodies did not inhibit cell cycle progression but instead reduced secretion of the angiogenic chemokine CXCL1 from head and neck cancer cells in vitro, thus acting here as inverse agonists, and subsequent angiogenesis in vivo. Hence, with this novel class of CXCR7 inhibitors, we further substantiate the therapeutic relevance of targeting CXCR7 in head and neck cancer.

The BRCT domain is a phospho-protein binding domain.

Science.gov (United States)

Yu, Xiaochun; Chini, Claudia Christiano Silva; He, Miao; Mer, Georges; Chen, Junjie

2003-10-24

The carboxyl-terminal domain (BRCT) of the Breast Cancer Gene 1 (BRCA1) protein is an evolutionarily conserved module that exists in a large number of proteins from prokaryotes to eukaryotes. Although most BRCT domain-containing proteins participate in DNA-damage checkpoint or DNA-repair pathways, or both, the function of the BRCT domain is not fully understood. We show that the BRCA1 BRCT domain directly interacts with phosphorylated BRCA1-Associated Carboxyl-terminal Helicase (BACH1). This specific interaction between BRCA1 and phosphorylated BACH1 is cell cycle regulated and is required for DNA damage-induced checkpoint control during the transition from G2 to M phase of the cell cycle. Further, we show that two other BRCT domains interact with their respective physiological partners in a phosphorylation-dependent manner. Thirteen additional BRCT domains also preferentially bind phospho-peptides rather than nonphosphorylated control peptides. These data imply that the BRCT domain is a phospho-protein binding domain involved in cell cycle control.

Domain analysis

DEFF Research Database (Denmark)

Hjørland, Birger

2017-01-01

The domain-analytic approach to knowledge organization (KO) (and to the broader field of library and information science, LIS) is outlined. The article reviews the discussions and proposals on the definition of domains, and provides an example of a domain-analytic study in the field of art studies....... Varieties of domain analysis as well as criticism and controversies are presented and discussed....

Inferring domain-domain interactions from protein-protein interactions with formal concept analysis.

Directory of Open Access Journals (Sweden)

Susan Khor

Full Text Available Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where the score of a domain-pair is the ratio between observed and expected frequencies because the protein-protein interaction network is sparse. As such, many protein-pairs will be non-interacting and domain-pairs with promiscuous domains will be penalized. This domain promiscuity challenge to the problem of inferring reliable domain-domain interactions from protein-protein interactions has been recognized, and a number of work-arounds have been proposed. This paper reports on an application of Formal Concept Analysis to this problem. It is found that the relationship between formal concepts provides a natural way for rare domains to elevate the rank of promiscuous domain-pairs and enrich highly ranked domain-pairs with reliable domain-domain interactions. This piggybacking of promiscuous domain-pairs onto less promiscuous domain-pairs is possible only with concept lattices whose attribute-labels are not reduced and is enhanced by the presence of proteins that comprise both promiscuous and rare domains.

Inferring Domain-Domain Interactions from Protein-Protein Interactions with Formal Concept Analysis

Science.gov (United States)

Khor, Susan

2014-01-01

Identifying reliable domain-domain interactions will increase our ability to predict novel protein-protein interactions, to unravel interactions in protein complexes, and thus gain more information about the function and behavior of genes. One of the challenges of identifying reliable domain-domain interactions is domain promiscuity. Promiscuous domains are domains that can occur in many domain architectures and are therefore found in many proteins. This becomes a problem for a method where the score of a domain-pair is the ratio between observed and expected frequencies because the protein-protein interaction network is sparse. As such, many protein-pairs will be non-interacting and domain-pairs with promiscuous domains will be penalized. This domain promiscuity challenge to the problem of inferring reliable domain-domain interactions from protein-protein interactions has been recognized, and a number of work-arounds have been proposed. This paper reports on an application of Formal Concept Analysis to this problem. It is found that the relationship between formal concepts provides a natural way for rare domains to elevate the rank of promiscuous domain-pairs and enrich highly ranked domain-pairs with reliable domain-domain interactions. This piggybacking of promiscuous domain-pairs onto less promiscuous domain-pairs is possible only with concept lattices whose attribute-labels are not reduced and is enhanced by the presence of proteins that comprise both promiscuous and rare domains. PMID:24586450

The Voltage-Sensing Domain of Kv7.2 Channels as a Molecular Target for Epilepsy-Causing Mutations and Anticonvulsants

Science.gov (United States)

Miceli, Francesco; Soldovieri, Maria Virginia; Iannotti, Fabio Arturo; Barrese, Vincenzo; Ambrosino, Paolo; Martire, Maria; Cilio, Maria Roberta; Taglialatela, Maurizio

2010-01-01

Understanding the molecular mechanisms underlying voltage-dependent gating in voltage-gated ion channels (VGICs) has been a major effort over the last decades. In recent years, changes in the gating process have emerged as common denominators for several genetically determined channelopathies affecting heart rhythm (arrhythmias), neuronal excitability (epilepsy, pain), or skeletal muscle contraction (periodic paralysis). Moreover, gating changes appear as the main molecular mechanism by which several natural toxins from a variety of species affect ion channel function. In this work, we describe the pathophysiological and pharmacological relevance of the gating process in voltage-gated K+ channels encoded by the Kv7 gene family. After reviewing the current knowledge on the molecular mechanisms and on the structural models of voltage-dependent gating in VGICs, we describe the physiological relevance of these channels, with particular emphasis on those formed by Kv7.2–Kv7.5 subunits having a well-established role in controlling neuronal excitability in humans. In fact, genetically determined alterations in Kv7.2 and Kv7.3 genes are responsible for benign familial neonatal convulsions, a rare seizure disorder affecting newborns, and the pharmacological activation of Kv7.2/3 channels can exert antiepileptic activity in humans. Both mutation-triggered channel dysfunction and drug-induced channel activation can occur by impeding or facilitating, respectively, channel sensitivity to membrane voltage and can affect overlapping molecular sites within the voltage-sensing domain of these channels. Thus, understanding the molecular steps involved in voltage-sensing in Kv7 channels will allow to better define the pathogenesis of rare human epilepsy, and to design innovative pharmacological strategies for the treatment of epilepsies and, possibly, other human diseases characterized by neuronal hyperexcitability. PMID:21687499

Low levels of methylmercury induce DNA damage in rats: protective effects of selenium

Energy Technology Data Exchange (ETDEWEB)

Grotto, Denise; Barcelos, Gustavo R.M.; Antunes, Lusania M.G.; Barbosa, Fernando [Universidade de Sao Paulo, Departamento de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Ribeirao Preto, Sao Paulo (Brazil); Valentini, Juliana [Universidade de Sao Paulo, Departamento de Analises Clinicas, Toxicologicas e Bromatologicas, Faculdade de Ciencias Farmaceuticas de Ribeirao Preto, Ribeirao Preto, Sao Paulo (Brazil); Universidade Federal de Santa Maria, Departamento de Analises Clinicas e Toxicologicas, Santa Maria, Rio Grande do Sul (Brazil); Angeli, Jose Pedro F. [Universidade de Sao Paulo, Departamento de Bioquimica, Instituto de Quimica, Sao Paulo (Brazil); Garcia, Solange C. [Universidade Federal de Santa Maria, Departamento de Analises Clinicas e Toxicologicas, Santa Maria, Rio Grande do Sul (Brazil)

2009-03-15

In this study we examined the possible antigenotoxic effect of selenium (Se) in rats chronically exposed to low levels of methylmercury (MeHg) and the association between glutathione peroxidase (GSH-Px) activity and DNA lesions (via comet assay) in the same exposed animals. Rats were divided into six groups as follows: (Group I) received water; (Group II) received MeHg (100 {mu}g/day); (Group III) received Se (2 mg/L drinking water); (Group IV) received Se (6 mg/L drinking water); (Group V) received MeHg (100 {mu}g/day) and Se (2 mg/L drinking water); (Group VI) received MeHg (100 {mu}g/day) and Se (6 mg/L drinking water). Total treatment time was 100 days. GSH-Px activity was determined spectrophotometrically and DNA damage was determined by comet assay. Mean GSH-Px activity in groups I, II, III, IV, V and VI were, respectively: 40.19{+-}17.21; 23.63{+-}6.04; 42.64{+-}5.70; 38.50{+-}7.15; 34.54{+-}6.18 and 41.39{+-}11.67 nmolNADPH/min/gHb. DNA damage was represented by a mean score from 0 to 300; the results for groups I, II, III, IV, V and VI were, respectively: 6.87{+-}3.27; 124.12{+-}13.74; 10.62{+-}3.81; 13.25{+-}1.76; 86.87{+-}11.95 and 76.25{+-}7.48. There was a significant inhibition of GSH-Px activity in group II compared with group I (P<0.05). Groups V and VI did not show a difference in enzyme activity compared with groups III and IV, showing the possible protective action of Se. Comet assay presented a significant difference in DNA migration between group II and group I (P<0.0001). Groups V and VI showed a significant reduction in MeHg-induced genotoxicity (P < 0.001) when compared with group II. A negative correlation (r = -0.559, P<0.05) was found between GSH-Px activity and DNA lesion, showing that the greater the DNA damage, the lower the GSH-Px activity. Our findings demonstrated the oxidative and genotoxic properties of MeHg, even at low doses. Moreover, Se co-administration reestablished GSH-Px activity and reduced DNA damage. (orig.)

MicroRNA-126 and epidermal growth factor-like domain 7-an angiogenic couple of importance in metastatic colorectal cancer. Results from the Nordic ACT trial

DEFF Research Database (Denmark)

Hansen, T F; Christensen, René dePont; Andersen, R F

2013-01-01

Background:This study investigated the clinical importance of linked angiogenetic biomarkers to chemotherapy, combined with the anti-vascular endothelial growth factor A (anti-VEGF-A), as a first-line treatment in patients with metastatic colorectal cancer (mCRC).Methods:A total of 230 patients......-like domain 7 (EGFL7) protein was visualised and quantified using immunohistochemistry.Results:High tumour expression of miRNA-126 was significantly related to a longer progression-free survival. The independent prognostic value of miRNA-126 was confirmed using a Cox regression analysis (hazard ratio=0.49, 95...... on the prognostic value of miRNA-126 in mCRC and may suggest a relationship between treatment efficacy and EGFL7 expression. As miRNA-126 may target VEGF-A as well as EGFL7, the results may provide predictive information in relation to next-generation anti-angiogenetics....

[Preparation and characterization of monoclonal antibodies against Micrococcus luteus Rpf domain].

Science.gov (United States)

Fan, Ai-lin; Shi, Chang-hong; Su, Ming-quan; Ma, Jing; Bai, Yin-lan; Cheng, Xiao-dong; Xu, Zhi-kai; Hao, Xiao-ke

2008-05-01

To express Micrococcus luteus Rpf domain in prokaryotic cells and prepare monoclonal antibodies against Rpf domain. The gene encoding Micrococcus luteus Rpf domain was amplified from genome of Micrococcus luteus by polymerase chain reaction(PCR), and inserted into cloning vector pUC-19. After sequenced, Micrococcus luteus Rpf domain gene was subcloned into the expression vector pPro-EXHT and transfected into E.coli DH5alpha. After induced by IPTG, the bacteria controlled by T7 promoter expressed the fused Micrococcus luteus Rpf domain protein with a hexahistidine tail at its N-terminal and the target protein was purified under denaturing conditions. Using this protein as antigen to immunize the BALB/c mice and prepare monoclonal antibodies against Micrococcus luteus Rpf domain. Then specifities and relative affinities of mAbs were identified by ELISA. The fusion protein was purified by metal chelate affinity chromatography under denaturing condition. Three cloned mAbs were prepared from the mice immunized by Rpf domain. All of them could recognize Rpf domain. specifically. The prepared mAbs against Rpf domain have strong specificity with high titers, which provides useful tools for further study of the function of Rpf domain in TB prevention.

The YARHG domain: an extracellular domain in search of a function.

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Penny Coggill

Full Text Available We have identified a new bacterial protein domain that we hypothesise binds to peptidoglycan. This domain is called the YARHG domain after the most highly conserved sequence-segment. The domain is found in the extracellular space and is likely to be composed of four alpha-helices. The domain is found associated with protein kinase domains, suggesting it is associated with signalling in some bacteria. The domain is also found associated with three different families of peptidases. The large number of different domains that are found associated with YARHG suggests that it is a useful functional module that nature has recombined multiple times.

Not all risks are created equal: A twin study and meta-analyses of risk taking across seven domains.

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Wang, X T Xiao-Tian; Zheng, Rui; Xuan, Yan-Hua; Chen, Jie; Li, Shu

2016-11-01

Humans routinely deal with both traditional and novel risks. Different kinds of risks have been a driving force for both evolutionary adaptations and personal development. This study explored the genetic and environmental influences on human risk taking in different task domains. Our approach was threefold. First, we integrated several scales of domain-specific risk-taking propensity and developed a synthetic scale, including both evolutionarily typical and modern risks in the following 7 domains: cooperation/competition, safety, reproduction, natural/physical risk, moral risk, financial risk, and gambling. Second, we conducted a twin study using the scale to estimate the contributions of genes and environment to risk taking in each of these 7 domains. Third, we conducted a series of meta-analyses of extant twin studies across the 7 risk domains. The results showed that individual differences in risk-taking propensity and its consistency across domains were mainly regulated by additive genetic influences and individually unique environmental experiences. The heritability estimates from the meta-analyses ranged from 29% in financial risk taking to 55% in safety. Supporting the notion of risk-domain specificity, both the behavioral and genetic correlations among the 7 domains were generally low. Among the relatively few correlations between pairs of risk domains, our analysis revealed a common genetic factor that regulates moral, financial, and natural/physical risk taking. This is the first effort to separate genetic and environmental influences on risk taking across multiple domains in a single study and integrate the findings of extant twin studies via a series of meta-analyses conducted in different task domains. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

.Gov Domains API

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General Services Administration — This dataset offers the list of all .gov domains, including state, local, and tribal .gov domains. It does not include .mil domains, or other federal domains outside...

The voltage-sensing domain of kv7.2 channels as a molecular target for epilepsy-causing mutations and anticonvulsants

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Francesco eMiceli

2011-02-01

Full Text Available Understanding the molecular mechanisms underlying voltage-dependent gating in voltage-gated ion channels (VGICs has been a major effort over the last decades. In recent years, changes in the gating process have emerged as common denominators for several genetically-determined channelopathies affecting heart rhythm (arrhythmias, neuronal excitability (epilepsy, pain or skeletal muscle contraction (periodic paralysis. Moreover, gating changes appear as the main molecular mechanism by which several natural toxins from a variety of species affect ion channel function.In this work, we describe the pathophysiological and pharmacological relevance of the gating process in voltage-gated K+ channels encoded by the Kv7 gene family. After reviewing the current knowledge on the molecular mechanisms and on the structural models of voltage-dependent gating in VGICs, we describe the physiological relevance of these channels, with particular emphasis on those formed by Kv7.2-5 subunits having a well-established role in controlling neuronal excitability in humans. In fact, genetically-determined alterations in Kv7.2 and Kv7.3 genes are responsible for benign familial neonatal convulsions, a rare seizure disorder affecting newborns, and the pharmacological activation of Kv7.2/3 channels can exert antiepileptic activity in humans. Both mutation-triggered channel dysfunction and drug-induced channel activation can occur by impeding or facilitating, respectively, channel sensitivity to membrane voltage and can affect overlapping molecular sites within the voltage-sensing domain of these channels. Thus, understanding the molecular steps involved in voltage-sensing in Kv7 channels will allow to better define the pathogenesis of rare human epilepsy, and to design innovative pharmacological strategies for the treatment of epilepsies and, possibly, other human diseases characterized by neuronal hyperexcitability.

Structural and mutational analysis of functional differentiation between synaptotagmins-1 and -7.

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Mingshan Xue

2010-09-01

Full Text Available Synaptotagmins are known to mediate diverse forms of Ca2+-triggered exocytosis through their C2 domains, but the principles underlying functional differentiation among them are unclear. Synaptotagmin-1 functions as a Ca2+ sensor in neurotransmitter release at central nervous system synapses, but synaptotagmin-7 does not, and yet both isoforms act as Ca2+ sensors in chromaffin cells. To shed light into this apparent paradox, we have performed rescue experiments in neurons from synaptotagmin-1 knockout mice using a chimera that contains the synaptotagmin-1 sequence with its C2B domain replaced by the synaptotagmin-7 C2B domain (Syt1/7. Rescue was not achieved either with the WT Syt1/7 chimera or with nine mutants where residues that are distinct in synaptotagmin-7 were restored to those present in synaptotagmin-1. To investigate whether these results arise because of unique conformational features of the synaptotagmin-7 C2B domain, we determined its crystal structure at 1.44 A resolution. The synaptotagmin-7 C2B domain structure is very similar to that of the synaptotagmin-1 C2B domain and contains three Ca2+-binding sites. Two of the Ca2+-binding sites of the synaptotagmin-7 C2B domain are also present in the synaptotagmin-1 C2B domain and have analogous ligands to those determined for the latter by NMR spectroscopy, suggesting that a discrepancy observed in a crystal structure of the synaptotagmin-1 C2B domain arose from crystal contacts. Overall, our results suggest that functional differentiation in synaptotagmins arises in part from subtle sequence changes that yield dramatic functional differences.

The Enzyme-Like Domain of Arabidopsis Nuclear β-Amylases Is Critical for DNA Sequence Recognition and Transcriptional Activation.

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Soyk, Sebastian; Simková, Klára; Zürcher, Evelyne; Luginbühl, Leonie; Brand, Luise H; Vaughan, Cara K; Wanke, Dierk; Zeeman, Samuel C

2014-04-01

Plant BZR1-BAM transcription factors contain a β-amylase (BAM)-like domain, characteristic of proteins involved in starch breakdown. The enzyme-derived domains appear to be noncatalytic, but they determine the function of the two Arabidopsis thaliana BZR1-BAM isoforms (BAM7 and BAM8) during transcriptional initiation. Removal or swapping of the BAM domains demonstrates that the BAM7 BAM domain restricts DNA binding and transcriptional activation, while the BAM8 BAM domain allows both activities. Furthermore, we demonstrate that BAM7 and BAM8 interact on the protein level and cooperate during transcriptional regulation. Site-directed mutagenesis of residues in the BAM domain of BAM8 shows that its function as a transcriptional activator is independent of catalysis but requires an intact substrate binding site, suggesting it may bind a ligand. Microarray experiments with plants overexpressing truncated versions lacking the BAM domain indicate that the pseudo-enzymatic domain increases selectivity for the preferred cis-regulatory element BBRE (BZR1-BAM Responsive Element). Side specificity toward the G-box may allow crosstalk to other signaling networks. This work highlights the importance of the enzyme-derived domain of BZR1-BAMs, supporting their potential role as metabolic sensors. © 2014 American Society of Plant Biologists. All rights reserved.

Frank-ter Haar syndrome protein Tks4 regulates epidermal growth factor-dependent cell migration.

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Bögel, Gábor; Gujdár, Annamária; Geiszt, Miklós; Lányi, Árpád; Fekete, Anna; Sipeki, Szabolcs; Downward, Julian; Buday, László

2012-09-07

Mutations in the SH3PXD2B gene coding for the Tks4 protein are responsible for the autosomal recessive Frank-ter Haar syndrome. Tks4, a substrate of Src tyrosine kinase, is implicated in the regulation of podosome formation. Here, we report a novel role for Tks4 in the EGF signaling pathway. In EGF-treated cells, Tks4 is tyrosine-phosphorylated and associated with the activated EGF receptor. This association is not direct but requires the presence of Src tyrosine kinase. In addition, treatment of cells with LY294002, an inhibitor of PI 3-kinase, or mutations of the PX domain reduces tyrosine phosphorylation and membrane translocation of Tks4. Furthermore, a PX domain mutant (R43W) Tks4 carrying a reported point mutation in a Frank-ter Haar syndrome patient showed aberrant intracellular expression and reduced phosphoinositide binding. Finally, silencing of Tks4 was shown to markedly inhibit HeLa cell migration in a Boyden chamber assay in response to EGF or serum. Our results therefore reveal a new function for Tks4 in the regulation of growth factor-dependent cell migration.

Same but not alike: Structure, flexibility and energetics of domains in multi-domain proteins are influenced by the presence of other domains.

Science.gov (United States)

Vishwanath, Sneha; de Brevern, Alexandre G; Srinivasan, Narayanaswamy

2018-02-01

The majority of the proteins encoded in the genomes of eukaryotes contain more than one domain. Reasons for high prevalence of multi-domain proteins in various organisms have been attributed to higher stability and functional and folding advantages over single-domain proteins. Despite these advantages, many proteins are composed of only one domain while their homologous domains are part of multi-domain proteins. In the study presented here, differences in the properties of protein domains in single-domain and multi-domain systems and their influence on functions are discussed. We studied 20 pairs of identical protein domains, which were crystallized in two forms (a) tethered to other proteins domains and (b) tethered to fewer protein domains than (a) or not tethered to any protein domain. Results suggest that tethering of domains in multi-domain proteins influences the structural, dynamic and energetic properties of the constituent protein domains. 50% of the protein domain pairs show significant structural deviations while 90% of the protein domain pairs show differences in dynamics and 12% of the residues show differences in the energetics. To gain further insights on the influence of tethering on the function of the domains, 4 pairs of homologous protein domains, where one of them is a full-length single-domain protein and the other protein domain is a part of a multi-domain protein, were studied. Analyses showed that identical and structurally equivalent functional residues show differential dynamics in homologous protein domains; though comparable dynamics between in-silico generated chimera protein and multi-domain proteins were observed. From these observations, the differences observed in the functions of homologous proteins could be attributed to the presence of tethered domain. Overall, we conclude that tethered domains in multi-domain proteins not only provide stability or folding advantages but also influence pathways resulting in differences in

Mechanistic insights into phosphoprotein-binding FHA domains.

Science.gov (United States)

Liang, Xiangyang; Van Doren, Steven R

2008-08-01

[Structure: see text]. FHA domains are protein modules that switch signals in diverse biological pathways by monitoring the phosphorylation of threonine residues of target proteins. As part of the effort to gain insight into cellular avoidance of cancer, FHA domains involved in the cellular response to DNA damage have been especially well-characterized. The complete protein where the FHA domain resides and the interaction partners determine the nature of the signaling. Thus, a key biochemical question is how do FHA domains pick out their partners from among thousands of alternatives in the cell? This Account discusses the structure, affinity, and specificity of FHA domains and the formation of their functional structure. Although FHA domains share sequence identity at only five loop residues, they all fold into a beta-sandwich of two beta-sheets. The conserved arginine and serine of the recognition loops recognize the phosphorylation of the threonine targeted. Side chains emanating from loops that join beta-strand 4 with 5, 6 with 7, or 10 with 11 make specific contacts with amino acids of the ligand that tailor sequence preferences. Many FHA domains choose a partner in extended conformation, somewhat according to the residue three after the phosphothreonine in sequence (pT + 3 position). One group of FHA domains chooses a short carboxylate-containing side chain at pT + 3. Another group chooses a long, branched aliphatic side chain. A third group prefers other hydrophobic or uncharged polar side chains at pT + 3. However, another FHA domain instead chooses on the basis of pT - 2, pT - 3, and pT + 1 positions. An FHA domain from a marker of human cancer instead chooses a much longer protein fragment that adds a beta-strand to its beta-sheet and that presents hydrophobic residues from a novel helix to the usual recognition surface. This novel recognition site and more remote sites for the binding of other types of protein partners were predicted for the entire family

Lectin Domains of Polypeptide GalNAc Transferases Exhibit Glycopeptide Binding Specificity

DEFF Research Database (Denmark)

Pedersen, Johannes W; Bennett, Eric P; Schjoldager, Katrine T-B G

2011-01-01

UDP-GalNAc:polypeptide a-N-acetylgalactosaminyltransferases (GalNAc-Ts) constitute a family of up to 20 transferases that initiate mucin-type O-glycosylation. The transferases are structurally composed of catalytic and lectin domains. Two modes have been identified for the selection...... of glycosylation sites by GalNAc-Ts: confined sequence recognition by the catalytic domain alone, and concerted recognition of acceptor sites and adjacent GalNAc-glycosylated sites by the catalytic and lectin domains, respectively. Thus far, only the catalytic domain has been shown to have peptide sequence...... on sequences of mucins MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC7 as well as a random glycopeptide bead library, we examined the binding properties of four different lectin domains. The lectin domains of GalNAc-T1, -T2, -T3, and -T4 bound different subsets of small glycopeptides. These results indicate...

Vesicular-Arbuscular Mycorrhiza in Field-Grown Crops. I. Mycorrhizal Infection in Cereals and Peas at Various Times and Soil Depths

DEFF Research Database (Denmark)

Jakobsen, Iver; Nielsen, N.E.

1983-01-01

Development of infection by vesicular-arbuscular mycorrhiza (VAM) was studied in some field-grown crops. An infection plateau was reached within the first month after seedling emergence of spring barley, oats and peas. During the rest of the growth period the proportion of root length infected by...... in relation to final phosphorus uptake and dry-matter production, and it is proposed that a relatively low soil-phosphorus availability was counterbalanced, to some extent, by a well-developed VAM infection....

Axenic culture and encapsulation of the intraradical forms of Glomus spp.

Science.gov (United States)

Strullu, D G; Romand, C; Plenchette, C

1991-05-01

In recent years there have been many attempts to cultivate in vitro vesicular-arbuscular mycorrhizal (VAM) fungi which are obligate symbionts. Resting spores extracted from soils are often used as inoculum. Mycorrhizal root pieces are also used for inoculation but the role of intra-radical structures has not been clearly established. On agar medium vegetative mycelium was regenerated from individual intra-radical vesicles and from hyphae extracted by enzymatic maceration. After cell penetration, the mycelium probably accumulates substances which allow growth of VAM fungi in pure culture. When associated with tomato roots, this mycelium forms typical mycorrhizae. Encapsulation stabilized the biological properties of mycorrhizal roots and isolated vesicles. The immobilization also preserved the infectivity of the intra-radical hyphae and vesicles. After 25 years of exclusive utilization of resting spores as starting material for axenic and dual cultures of VAM fungi, it appears that intra-radical vesicles may be preferable propagules.

Voice advisory manikin versus instructor facilitated training in cardiopulmonary resuscitation

DEFF Research Database (Denmark)

Isbye, Dan L; Høiby, Pernilla; Rasmussen, Maria B

2008-01-01

BACKGROUND: Training of healthcare staff in cardiopulmonary resuscitation (CPR) is time-consuming and costly. It has been suggested to replace instructor facilitated (IF) training with an automated voice advisory manikin (VAM), which increases skill level by continuous verbal feedback during...... individual training. AIMS: To compare a VAM (ResusciAnne CPR skills station, Laerdal Medical A/S, Norway) with IF training in CPR using a bag-valve-mask (BVM) in terms of skills retention after 3 months. METHODS: Forty-three second year medical students were included and CPR performance (ERC Guidelines...... for Resuscitation 2005) was assessed in a 2 min test before randomisation to either IF training in groups of 8 or individual VAM training. Immediately after training and after 3 months, CPR performance was assessed in identical 2 min tests. Laerdal PC Skill Reporting System 2.0 was used to collect data. To quantify...

Soil microbiology in land reclamation volume II - mycorrhizae

Energy Technology Data Exchange (ETDEWEB)

Graves, D.H. (ed.)

1984-01-01

This volume contains three separate reports: RRTAC 84-4 (Greenhouse pot studies dealing with amendment of oil sand tailings: effects of peat, sewage sludge and fertilizer on plant growth, mycorrhizae and microbial activity); RRTAC 84-8 (Vesicular-arbuscular mycorrhizal (VAM) development of slender wheatgrass on amended oil sand tailings and subalpine coal mines spoil); RRTAC 84-7 (Ectomycorrhizae in amended oil sand tailings and subalpine coal mine spoil and in undisturbed Jack pine and spruce stands). In the first report mixtures of two peats were used to amend oil sand tailings and either mineral fertilizers or sewage sludge were added at different rates. The growth of slender wheat grass and jack pine grown in the greenhouse in these media were monitored. In the second report the VAM development of slender wheatgrass was monitored over a 4 year period; in the third the mycorrhizal status of jack pine and bear berry grown in oil sand tailings treated with various amendments and of white spruce and willow grown in subalpine coal mine spoil were monitored over the same period.

The Voltage-Sensing Domain of K(v)7.2 Channels as a Molecular Target for Epilepsy-Causing Mutations and Anticonvulsants.

Science.gov (United States)

Miceli, Francesco; Soldovieri, Maria Virginia; Iannotti, Fabio Arturo; Barrese, Vincenzo; Ambrosino, Paolo; Martire, Maria; Cilio, Maria Roberta; Taglialatela, Maurizio

2011-01-01

Understanding the molecular mechanisms underlying voltage-dependent gating in voltage-gated ion channels (VGICs) has been a major effort over the last decades. In recent years, changes in the gating process have emerged as common denominators for several genetically determined channelopathies affecting heart rhythm (arrhythmias), neuronal excitability (epilepsy, pain), or skeletal muscle contraction (periodic paralysis). Moreover, gating changes appear as the main molecular mechanism by which several natural toxins from a variety of species affect ion channel function. In this work, we describe the pathophysiological and pharmacological relevance of the gating process in voltage-gated K(+) channels encoded by the K(v)7 gene family. After reviewing the current knowledge on the molecular mechanisms and on the structural models of voltage-dependent gating in VGICs, we describe the physiological relevance of these channels, with particular emphasis on those formed by K(v)7.2-K(v)7.5 subunits having a well-established role in controlling neuronal excitability in humans. In fact, genetically determined alterations in K(v)7.2 and K(v)7.3 genes are responsible for benign familial neonatal convulsions, a rare seizure disorder affecting newborns, and the pharmacological activation of K(v)7.2/3 channels can exert antiepileptic activity in humans. Both mutation-triggered channel dysfunction and drug-induced channel activation can occur by impeding or facilitating, respectively, channel sensitivity to membrane voltage and can affect overlapping molecular sites within the voltage-sensing domain of these channels. Thus, understanding the molecular steps involved in voltage-sensing in K(v)7 channels will allow to better define the pathogenesis of rare human epilepsy, and to design innovative pharmacological strategies for the treatment of epilepsies and, possibly, other human diseases characterized by neuronal hyperexcitability.

A conserved gene family encodes transmembrane proteins with fibronectin, immunoglobulin and leucine-rich repeat domains (FIGLER

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Haga Christopher L

2007-09-01

Full Text Available Abstract Background In mouse the cytokine interleukin-7 (IL-7 is required for generation of B lymphocytes, but human IL-7 does not appear to have this function. A bioinformatics approach was therefore used to identify IL-7 receptor related genes in the hope of identifying the elusive human cytokine. Results Our database search identified a family of nine gene candidates, which we have provisionally named fibronectin immunoglobulin leucine-rich repeat (FIGLER. The FIGLER 1–9 genes are predicted to encode type I transmembrane glycoproteins with 6–12 leucine-rich repeats (LRR, a C2 type Ig domain, a fibronectin type III domain, a hydrophobic transmembrane domain, and a cytoplasmic domain containing one to four tyrosine residues. Members of this multichromosomal gene family possess 20–47% overall amino acid identity and are differentially expressed in cell lines and primary hematopoietic lineage cells. Genes for FIGLER homologs were identified in macaque, orangutan, chimpanzee, mouse, rat, dog, chicken, toad, and puffer fish databases. The non-human FIGLER homologs share 38–99% overall amino acid identity with their human counterpart. Conclusion The extracellular domain structure and absence of recognizable cytoplasmic signaling motifs in members of the highly conserved FIGLER gene family suggest a trophic or cell adhesion function for these molecules.

effect of two rock phosphates and inoculation with VA mycorrhizae and phosphate solubilizing bacteria on the chickpea-rhizobium symbiosis

International Nuclear Information System (INIS)

Soliman, S.M.; Galal, Y.G.M.; El-Ghandour, I.A.

2004-01-01

A pot experiment was conducted tracing the effect of two types of phosphorus applied at different rates on the release of nitrogen from fertilizer and its impact on biological nitrogen fixation . chickpea (Cicer Arietinum c v. Cicer 36-ICARDA) was inoculated with peat-based inoculum of phosphorin (Bacillus Megatherium phosphate solubilizing bacteria), Mycorrhizae (VAM) and a mixture of phosphorin and VAM. three types of P fertilizer, i.e.superphosphate, rock P 1 (Safaga) and rock P2 (Abou-Trtour) were applied at rate of 25 and 50 mg Pkg -1 soil in the presence or absence of inoculum. labelled ammonium sulfate with 15 N 10% atom excess was applied at rates of 15 and 30 mg N kg -1 soil for chickpea and barley (reference crop) respectively . Addition of phosphorus fertilizers, especially at the high rates, positively affected the growth and dry weight as compared to the unfertilized control. infections with VAM mixed with phosphorin under low level of rock P (Abou-tarour) gave the highest values of dry weight and N and P uptake when compared with both superphosphate-P source and control. biological N 2 fixed was higher in dual inoculation treatments (i.e.phosphorin +VAM) than those receiving a single inoculum. the percentages of N 2 -fixed ranged from 24 to 53 according to inoculation treatments, P sources and levels

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.

Comparative pharmacokinetics of caffeine and its primary demethylated metabolites paraxanthine, theobromine and theophylline in man.

Science.gov (United States)

Lelo, A; Birkett, D J; Robson, R A; Miners, J O

1986-01-01

The pharmacokinetics of caffeine (CA), paraxanthine (PX), theobromine (TB) and theophylline (TP) were studied in six healthy male volunteers after oral administration of each compound on separate occasions. The total plasma clearances of CA and PX were similar in value (2.07 and 2.20 ml min-1 kg-1, respectively) as were those for TP and TB (0.93 and 1.20 ml min-1 kg-1, respectively). The unbound plasma clearances of CA and PX were also similar in magnitude (3.11 and 4.14 ml min-1 kg-1, respectively) as were those of TP and TB (1.61 and 1.39 ml min-1 kg-1, respectively). The half-lives of TP and TB (6.2 and 7.2 h, respectively) were significantly longer than those of CA and PX (4.1 and 3.1 h, respectively). The volume of distribution at steady state of TP (0.44 l kg-1) was lower than that of the other methylxanthines (0.63-0.72 l kg-1). The unbound volume of distribution of TP (0.77 l kg-1) was however the same as that of TB (0.79 l kg-1) whereas the unbound volume of distribution of PX (1.18 l kg-1) was similar to that of CA (1.06 l kg-1). PMID:3756065

The domain architecture of large guanine nucleotide exchange factors for the small GTP-binding protein Arf

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Geldner Niko

2005-02-01

Full Text Available Abstract Background Small G proteins, which are essential regulators of multiple cellular functions, are activated by guanine nucleotide exchange factors (GEFs that stimulate the exchange of the tightly bound GDP nucleotide by GTP. The catalytic domain responsible for nucleotide exchange is in general associated with non-catalytic domains that define the spatio-temporal conditions of activation. In the case of small G proteins of the Arf subfamily, which are major regulators of membrane trafficking, GEFs form a heterogeneous family whose only common characteristic is the well-characterized Sec7 catalytic domain. In contrast, the function of non-catalytic domains and how they regulate/cooperate with the catalytic domain is essentially unknown. Results Based on Sec7-containing sequences from fully-annotated eukaryotic genomes, including our annotation of these sequences from Paramecium, we have investigated the domain architecture of large ArfGEFs of the BIG and GBF subfamilies, which are involved in Golgi traffic. Multiple sequence alignments combined with the analysis of predicted secondary structures, non-structured regions and splicing patterns, identifies five novel non-catalytic structural domains which are common to both subfamilies, revealing that they share a conserved modular organization. We also report a novel ArfGEF subfamily with a domain organization so far unique to alveolates, which we name TBS (TBC-Sec7. Conclusion Our analysis unifies the BIG and GBF subfamilies into a higher order subfamily, which, together with their being the only subfamilies common to all eukaryotes, suggests that they descend from a common ancestor from which species-specific ArfGEFs have subsequently evolved. Our identification of a conserved modular architecture provides a background for future functional investigation of non-catalytic domains.

Is the isolated ligand binding domain a good model of the domain in the native receptor?

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Deming, Dustin; Cheng, Qing; Jayaraman, Vasanthi

2003-05-16

Numerous studies have used the atomic level structure of the isolated ligand binding domain of the glutamate receptor to elucidate the agonist-induced activation and desensitization processes in this group of proteins. However, no study has demonstrated the structural equivalence of the isolated ligand binding fragments and the protein in the native receptor. In this report, using visible absorption spectroscopy we show that the electronic environment of the antagonist 6-cyano-7-nitro-2,3-dihydroxyquinoxaline is identical for the isolated protein and the native glutamate receptors expressed in cells. Our results hence establish that the local structure of the ligand binding site is the same in the two proteins and validate the detailed structure-function relationships that have been developed based on a comparison of the structure of the isolated ligand binding domain and electrophysiological consequences in the native receptor.

Domain decomposition method for solving elliptic problems in unbounded domains

International Nuclear Information System (INIS)

Khoromskij, B.N.; Mazurkevich, G.E.; Zhidkov, E.P.

1991-01-01

Computational aspects of the box domain decomposition (DD) method for solving boundary value problems in an unbounded domain are discussed. A new variant of the DD-method for elliptic problems in unbounded domains is suggested. It is based on the partitioning of an unbounded domain adapted to the given asymptotic decay of an unknown function at infinity. The comparison of computational expenditures is given for boundary integral method and the suggested DD-algorithm. 29 refs.; 2 figs.; 2 tabs

Vacuum-assisted microwave drying characteristics of green bell pepper

Directory of Open Access Journals (Sweden)

Vivek Kumar

2017-04-01

Full Text Available Chopped green bell pepper pieces were blanched (95 °C, 5 min and chemically pretreated (1% potassium metabisulphite solution, 25 min at room temperature before drying in hot air dryer (HAD at various temperature ranges (60 – 80 °C. Three vacuum levels (200, 400, 600 mm Hg and microwave power levels (100, 200, 300 W were also used to dry green bell pepper samples in a vacuum assisted microwave (VAM (2.45 GHz, 0.8 kW dryer. VAM drying methods offered a maximum reduction by four to five times in drying time as compared to that in HAD. The logarithmic model was found to have the best fit based on high R2 and small values of reduced χ2 and RMSE.  VAM method has higher values for effective moisture diffusivity (Deff and lower values for activation energy (Ea, in comparison to the HAD method. 

Crystallization and preliminary crystallographic analysis of an Escherichia coli-selected mutant of the nuclease domain of the metallonuclease colicin E7

DEFF Research Database (Denmark)

Czene, Aniko; Toth, Eszter; Gyurcsik, Bela

2013-01-01

The metallonuclease colicin E7 is a member of the HNH family of endonucleases. It serves as a bacterial toxin in Escherichia coli, protecting the host cell from other related bacteria and bacteriophages by degradation of their chromosomal DNA under environmental stress. Its cell-killing activity ....... X-ray diffraction data were collected to 1.6 Å resolution and could be indexed and averaged in the trigonal space group P3121 or P3221, with unit-cell parameters a = b = 55.4, c = 73.1 Å. Structure determination by molecular replacement is in progress.......The metallonuclease colicin E7 is a member of the HNH family of endonucleases. It serves as a bacterial toxin in Escherichia coli, protecting the host cell from other related bacteria and bacteriophages by degradation of their chromosomal DNA under environmental stress. Its cell-killing activity...... is attributed to the nonspecific nuclease domain (NColE7), which possesses the catalytic ββα-type metal ion-binding HNH motif at its C-terminus. Mutations affecting the positively charged amino acids at the N-terminus of NColE7 (444-576) surprisingly showed no or significantly reduced endonuclease activity...

Controlling the switching field in nanomagnets by means of domain-engineered antiferromagnets

Science.gov (United States)

Folven, E.; Linder, J.; Gomonay, O. V.; Scholl, A.; Doran, A.; Young, A. T.; Retterer, S. T.; Malik, V. K.; Tybell, T.; Takamura, Y.; Grepstad, J. K.

2015-09-01

Using soft x-ray spectromicroscopy, we investigate the magnetic domain structure in embedded nanomagnets defined in L a0.7S r0.3Mn O3 thin films and LaFe O3/L a0.7S r0.3Mn O3 bilayers. We find that shape-controlled antiferromagnetic domain states give rise to a significant reduction of the switching field of the rectangular nanomagnets. This is discussed within the framework of competition between an intrinsic spin-flop coupling and shape anisotropy. The data demonstrates that shape effects in antiferromagnets may be used to control the magnetic properties in nanomagnets.

The SHOCT domain: a widespread domain under-represented in model organisms.

Directory of Open Access Journals (Sweden)

Ruth Y Eberhardt

Full Text Available We have identified a new protein domain, which we have named the SHOCT domain (Short C-terminal domain. This domain is widespread in bacteria with over a thousand examples. But we found it is missing from the most commonly studied model organisms, despite being present in closely related species. It's predominantly C-terminal location, co-occurrence with numerous other domains and short size is reminiscent of the Gram-positive anchor motif, however it is present in a much wider range of species. We suggest several hypotheses about the function of SHOCT, including oligomerisation and nucleic acid binding. Our initial experiments do not support its role as an oligomerisation domain.

Nucleation and evaporation of domains due to electric field at room ...

Indian Academy of Sciences (India)

Administrator

by methanol, since methanol acts as a cleaning agent and removes impurity clusters from the surfaces.21. This suggests that these areas marked by N and P correspond to the 180° domains. Photomicrograph shown in figure 7b is again of the same surface as referred in figure 7a but now with the electric field of about 7 kV ...

Domain-to-domain coupling in voltage-sensing phosphatase.

Science.gov (United States)

Sakata, Souhei; Matsuda, Makoto; Kawanabe, Akira; Okamura, Yasushi

2017-01-01

Voltage-sensing phosphatase (VSP) consists of a transmembrane voltage sensor and a cytoplasmic enzyme region. The enzyme region contains the phosphatase and C2 domains, is structurally similar to the tumor suppressor phosphatase PTEN, and catalyzes the dephosphorylation of phosphoinositides. The transmembrane voltage sensor is connected to the phosphatase through a short linker region, and phosphatase activity is induced upon membrane depolarization. Although the detailed molecular characteristics of the voltage sensor domain and the enzyme region have been revealed, little is known how these two regions are coupled. In addition, it is important to know whether mechanism for coupling between the voltage sensor domain and downstream effector function is shared among other voltage sensor domain-containing proteins. Recent studies in which specific amino acid sites were genetically labeled using a fluorescent unnatural amino acid have enabled detection of the local structural changes in the cytoplasmic region of Ciona intestinalis VSP that occur with a change in membrane potential. The results of those studies provide novel insight into how the enzyme activity of the cytoplasmic region of VSP is regulated by the voltage sensor domain.

Erythrocytic glutathione peroxidase: Its relationship to plasma selenium in man

International Nuclear Information System (INIS)

Perona, G.; Cellerino, R.; Guidi, G.C.; Moschini, G.; Stievano, B.M.; Tregnaghi, C.

1977-01-01

Erythrocytic glutathione-peroxidase (GSH-Px) activity and plasma selenium concentrations were measured in 14 patients: 7 with iron deficiency and 7 with raised serum iron levels. The decreased enzymatic activity in iron deficiency was confirmed. Plasma selenium was significantly lower in patients with lower serum iron; furthermore there is a significant correlation between serum iron and plasma selenium concentrations. Another correlation even more significant was found between plasma selenium and enzyme activity in all the cases we studied. These data suggests that the importance of iron for GSH-Px activity may be merely due to its relationship with selenium and that plasma selenium concentration may be of critical importance for enzyme activity. (author)

MIT domain of Vps4 is a Ca2+-dependent phosphoinositide-binding domain.

Science.gov (United States)

Iwaya, Naoko; Takasu, Hirotoshi; Goda, Natsuko; Shirakawa, Masahiro; Tanaka, Toshiki; Hamada, Daizo; Hiroaki, Hidekazu

2013-05-01

The microtubule interacting and trafficking (MIT) domain is a small protein module that is conserved in proteins of diverged function, such as Vps4, spastin and sorting nexin 15 (SNX15). The molecular function of the MIT domain is protein-protein interaction, in which the domain recognizes peptides containing MIT-interacting motifs. Recently, we identified an evolutionarily related domain, 'variant' MIT domain at the N-terminal region of the microtubule severing enzyme katanin p60. We found that the domain was responsible for binding to microtubules and Ca(2+). Here, we have examined whether the authentic MIT domains also bind Ca(2+). We found that the loop between the first and second α-helices of the MIT domain binds a Ca(2+) ion. Furthermore, the MIT domains derived from Vps4b and SNX15a showed phosphoinositide-binding activities in a Ca(2+)-dependent manner. We propose that the MIT domain is a novel membrane-associating domain involved in endosomal trafficking.

Symmetrical refolding of protein domains and subunits: example of the dimeric two-domain 3-isopropylmalate dehydrogenases.

Science.gov (United States)

Gráczer, Eva; Varga, Andrea; Melnik, Bogdan; Semisotnov, Gennady; Závodszky, Péter; Vas, Mária

2009-02-10

The refolding mechanism of the homodimeric two-domain 3-isopropylmalate dehydrogenase (IPMDH) from the organisms adapted to different temperatures, Thermus thermophilus (Tt), Escherichia coli (Ec), and Vibrio sp. I5 (Vib), is described. In all three cases, instead of a self-template mechanism, the high extent of symmetry and cooperativity in folding of subunits and domains have been concluded from the following experimental findings: The complex time course of refolding, monitored by Trp fluorescence, consists of a fast (the rate constant varies as 16.5, 25.0, and 11.7 min-1 in the order of Tt, Ec, and Vib IPMDHs) and a slow (the rate constants are 0.11, 0.80, and 0.23 min-1 for the three different species) first-order process. However, a burst increase of Trp fluorescence anisotropy to the value of the native states indicates that in all three cases the association of the two polypeptide chains occurs at the beginning of refolding. This dimeric species binds the substrate IPM, but the native-like interactions of the tertiary and quaternary structures are only formed during the slow phase of refolding, accompanied by further increase of protein fluorescence and appearance of FRET between Trp side chain(s) and the bound NADH. Joining the contacting arms of each subunit also takes place exclusively during this slow phase. To monitor refolding of each domain within the intact molecule of T. thermophilus IPMDH, Trp's (located in separate domains) were systematically replaced with Phe's. The refolding processes of the mutants were followed by measuring changes in Trp fluorescence and in FRET between the particular Trp and NADH. The high similarity of time courses (both in biphasicity and in their rates) strongly suggests cooperative folding of the domains during formation of the native three-dimensional structure of IPMDH.

Environmental magneto-gradiometric marine survey in a highly anthropic noisy area

Directory of Open Access Journals (Sweden)

Luca Cocchi

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">We describe a magneto-gradiometric survey performed in the «Mar Piccolo» of Taranto, Italy in May 2005 for

px 0.0px 0.0px 0.0px; font: 9.0px Times;">environmental purposes. This region, which is a noisy harbour environment, provides a challenging test for magnetic methods. To reduce spurious noise signals, with both temporal and spatial origins, we used two Geometrics G880 model caesium magnetometers towed in a transverse gradient configuration. We show how, in shallow waters, this gradiometric configuration allows us to distinguish anomalies due to small metallic bodies near the seabed from the induced noise due to the anthropic contribution and geomagnetic field variations. A direct visual inspection confirmed that the peculiarities highlighted in the gradient anomaly map were due to abandoned metallic objects found on the seabed.

The scientific correspondence of Arcangelo Scacchi

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Rossella De Ceglie

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">The scientist Arcangelo Scacchi (1810-1893, is today rarely mentioned in histories of Italian science in the

px 0.0px 0.0px 0.0px; font: 9.0px Times;">nineteenth century. Even a brief consideration of his career, however, reveals that his work was of great importance to the scientific community of his age. For more than fifty years he was Professor of Mineralogy at the University of Naples and Curator of the Royal Mineralogical Museum, which under his guidance enjoyed a period of unprecedented success. The as yet unpublished Scacchi papers shed interesting light on the world of this Italian naturalist. His correspondence reveals much about Scacchi’s role in the scientific community both in Italy and abroad, and illustrate the extent to which he was involved in contemporary debates and research in the fields of geology, mineralogy, volcanology and crystallography.

Scientists and scientific associations in Catalonia (Spain in the early 20th century: manuscript vs. published research in earth sciences

Directory of Open Access Journals (Sweden)

Josep Batlló

2009-06-01

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px 0.0px 0.0px 0.0px; font: 9.0px Times;">

px 0.0px 0.0px 0.0px; font: 9.0px Times;">Culture in Catalonia and, specifically, science had an important rebirth in the second half of the 19th century. But, due to the lack of State support, development of earth physical sciences in Catalonia at the beginning of the 20th century was almost a private enterprise. This situation caused dispersion of the efforts that, in any case, were extensive. The study of the evolution of earth sciences and the recovery and study of the accumulated data in such circumstances requires relying heavily on manuscript information. The present study deals with the problems and possibilities of this situation, shows some study cases and extracts some conclusions of general interest from them.

Calcium uptake by cowpea as influenced by mycorrhizal colonization and water stress

International Nuclear Information System (INIS)

Pai, G.; Bagyaraj, D.J.; Padmavathi Ravindra, T.; Prasad, T.G.

1994-01-01

The role of vesicular-arbuscular mycorrhizal (VAM) colonization on calcium uptake was studied under different levels of moisture stress. Pots maintained at different moisture levels were given water containing known amount of radioactive calcium. The radioactivity in different parts of the plant was assessed 60 h after giving 45 Ca to the soil. High 45 Ca activity was present in all parts of vesicular-arbuscular mycrrohizal (VAM) plants compared to non-mycorrhizal plants at all levels of moisture stress. (author). 14 refs., 1 tab

Optimizing medical device buying. Value analysis models can help you improve decision-making process.

Science.gov (United States)

Feldstein, Josh; Brooks, Elizabeth

2010-05-01

Value Analysis Models (VAMs) are a burgeoning analytical tool that can help materials managers, operating room managers, CFOs and others to make comparative value assessments before reaching a critical purchasing decision. Although relatively new to the hospital field, more and more manufacturers are supporting these initiatives to bring critical information to their customers and the health care industry. VAMs aren't designed to conclude that one product is better than another but to be a tool that can help make the product acquisition process much easier.

Effects of Transportation on Antioxidant Status in Cynomolgus Macaques (Macaca fascicularis).

Science.gov (United States)

Pan, Xueying; Lu, Liang; Zeng, Xiancheng; Chang, Yan; Hua, Xiuguo

2016-01-01

To evaluate the effects of transportation on oxidative stress in cynomolgus monkeys, we measured serum levels of reduced glutathione (GSH), malondialdehyde, and protein carbonyl (PC) and the activities of total antioxidant capacity (TAOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase in cynomolgus macaques before transportation (day 0), on the day of arrival (day 1), and on days 7, 14, and 21 after transportation. Compared with that on day 0, TAOC and catalase activities on days 1, 7, and 14 after transportation were significantly decreased, reached their nadirs on day 7, and increased thereafter to reach their pretransportation levels by day 21 after transportation. Compared with day 0 levels, mean SOD activity and GSH concentration were decreased significantly on day 1; they thereafter increased to reach their pretransportation measures by day 7 after transportation. In contrast, PC and malondialdehyde concentrations in serum and the activity of GSH-Px were increased on day 1 compared with day 0 and thereafter decreased to reach their pretransportation levels by day 14 after transportation. In summary, GSH, TAOC, catalase, and SOD levels decreased and malondialdehyde, PC, and GSH-Px concentrations increased in cynomolgus macaques after transportation. These results suggest that transportation might imbalance oxidant and antioxidant levels to create excess oxidative stress in cynomolgus macaques. Therefore, cynomolgus macaques should have at least 21 d to recover after transportation and regain their healthy status.

Conversion of Dielectric Data from the Time Domain to the Frequency Domain

Directory of Open Access Journals (Sweden)

Vladimir Durman

2005-01-01

Full Text Available Polarisation and conduction processes in dielectric systems can be identified by the time domain or the frequency domain measurements. If the systems is a linear one, the results of the time domain measurements can be transformed into the frequency domain, and vice versa. Commonly, the time domain data of the absorption conductivity are transformed into the frequency domain data of the dielectric susceptibility. In practice, the relaxation are mainly evaluated by the frequency domain data. In the time domain, the absorption current measurement were prefered up to now. Recent methods are based on the recovery voltage measurements. In this paper a new method of the recovery data conversion from the time the frequency domain is proposed. The method is based on the analysis of the recovery voltage transient based on the Maxwell equation for the current density in a dielectric. Unlike the previous published solutions, the Laplace fransform was used to derive a formula suitable for practical purposes. the proposed procedure allows also calculating of the insulation resistance and separating the polarisation and conduction losses.

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

2016-02-27

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.

Explaining the Substantial Inter-Domain and Over-Time Correlations in Student Achievement: The Importance of Stable Student Attributes

Science.gov (United States)

Marks, Gary N.

2016-01-01

Multi-domain and longitudinal studies of student achievement routinely find moderate to strong correlations across achievement domains and even stronger within-domain correlations over time. The purpose of this study is to examine the sources of these patterns analysing student achievement in 5 domains across Years 3, 5 and 7. The analysis is of…

Flexible time domain averaging technique

Science.gov (United States)

Zhao, Ming; Lin, Jing; Lei, Yaguo; Wang, Xiufeng

2013-09-01

Time domain averaging(TDA) is essentially a comb filter, it cannot extract the specified harmonics which may be caused by some faults, such as gear eccentric. Meanwhile, TDA always suffers from period cutting error(PCE) to different extent. Several improved TDA methods have been proposed, however they cannot completely eliminate the waveform reconstruction error caused by PCE. In order to overcome the shortcomings of conventional methods, a flexible time domain averaging(FTDA) technique is established, which adapts to the analyzed signal through adjusting each harmonic of the comb filter. In this technique, the explicit form of FTDA is first constructed by frequency domain sampling. Subsequently, chirp Z-transform(CZT) is employed in the algorithm of FTDA, which can improve the calculating efficiency significantly. Since the signal is reconstructed in the continuous time domain, there is no PCE in the FTDA. To validate the effectiveness of FTDA in the signal de-noising, interpolation and harmonic reconstruction, a simulated multi-components periodic signal that corrupted by noise is processed by FTDA. The simulation results show that the FTDA is capable of recovering the periodic components from the background noise effectively. Moreover, it can improve the signal-to-noise ratio by 7.9 dB compared with conventional ones. Experiments are also carried out on gearbox test rigs with chipped tooth and eccentricity gear, respectively. It is shown that the FTDA can identify the direction and severity of the eccentricity gear, and further enhances the amplitudes of impulses by 35%. The proposed technique not only solves the problem of PCE, but also provides a useful tool for the fault symptom extraction of rotating machinery.

Eukaryotic ribonucleases P/MRP: the crystal structure of the P3 domain.

Science.gov (United States)

Perederina, Anna; Esakova, Olga; Quan, Chao; Khanova, Elena; Krasilnikov, Andrey S

2010-02-17

Ribonuclease (RNase) P is a site-specific endoribonuclease found in all kingdoms of life. Typical RNase P consists of a catalytic RNA component and a protein moiety. In the eukaryotes, the RNase P lineage has split into two, giving rise to a closely related enzyme, RNase MRP, which has similar components but has evolved to have different specificities. The eukaryotic RNases P/MRP have acquired an essential helix-loop-helix protein-binding RNA domain P3 that has an important function in eukaryotic enzymes and distinguishes them from bacterial and archaeal RNases P. Here, we present a crystal structure of the P3 RNA domain from Saccharomyces cerevisiae RNase MRP in a complex with RNase P/MRP proteins Pop6 and Pop7 solved to 2.7 A. The structure suggests similar structural organization of the P3 RNA domains in RNases P/MRP and possible functions of the P3 domains and proteins bound to them in the stabilization of the holoenzymes' structures as well as in interactions with substrates. It provides the first insight into the structural organization of the eukaryotic enzymes of the RNase P/MRP family.

Regulator of G Protein Signaling 7 (RGS7) Can Exist in a Homo-oligomeric Form That Is Regulated by Gαo and R7-binding Protein.

Science.gov (United States)

Tayou, Junior; Wang, Qiang; Jang, Geeng-Fu; Pronin, Alexey N; Orlandi, Cesare; Martemyanov, Kirill A; Crabb, John W; Slepak, Vladlen Z

2016-04-22

RGS (regulator of G protein signaling) proteins of the R7 subfamily (RGS6, -7, -9, and -11) are highly expressed in neurons where they regulate many physiological processes. R7 RGS proteins contain several distinct domains and form obligatory dimers with the atypical Gβ subunit, Gβ5 They also interact with other proteins such as R7-binding protein, R9-anchoring protein, and the orphan receptors GPR158 and GPR179. These interactions facilitate plasma membrane targeting and stability of R7 proteins and modulate their activity. Here, we investigated RGS7 complexes using in situ chemical cross-linking. We found that in mouse brain and transfected cells cross-linking causes formation of distinct RGS7 complexes. One of the products had the apparent molecular mass of ∼150 kDa on SDS-PAGE and did not contain Gβ5 Mass spectrometry analysis showed no other proteins to be present within the 150-kDa complex in the amount close to stoichiometric with RGS7. This finding suggested that RGS7 could form a homo-oligomer. Indeed, co-immunoprecipitation of differentially tagged RGS7 constructs, with or without chemical cross-linking, demonstrated RGS7 self-association. RGS7-RGS7 interaction required the DEP domain but not the RGS and DHEX domains or the Gβ5 subunit. Using transfected cells and knock-out mice, we demonstrated that R7-binding protein had a strong inhibitory effect on homo-oligomerization of RGS7. In contrast, our data indicated that GPR158 could bind to the RGS7 homo-oligomer without causing its dissociation. Co-expression of constitutively active Gαo prevented the RGS7-RGS7 interaction. These results reveal the existence of RGS protein homo-oligomers and show regulation of their assembly by R7 RGS-binding partners. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Vertical selection in the information domain of children

NARCIS (Netherlands)

Duarte Torres, Sergio; Hiemstra, Djoerd; Huibers, Theo W.C.

In this paper we explore the vertical selection methods in aggregated search in the specific domain of topics for children between 7 and 12 years old. A test collection consisting of 25 verticals, 3.8K queries and relevant assessments for a large sample of these queries mapping relevant verticals to

Enzymatic studies on phosphorus availability from phosphate compounds by microbial activities using nuclear techniques

International Nuclear Information System (INIS)

Abou Seer, A.M.M.

2002-01-01

the present study aimed to evaluate to evaluate the of phosphate solubilizing bacteria (PSB) and vesicular arbuscular mycorrhizae(VAM) as microbiological mean to convert the sparingly soluble P into available from utilized by plant through excretion of acid and alkaline phosphatase. rock phosphate as natural and a cheap source of P- fertilizer was applied in the present study. To trace the effect of microbial activity and phosphatase enzymes on phosphate availability from its compounds , set of experiments were conducted either in the lab. or green house. The obtained results could be summarized as following:- 1- phosphate solubilizing bacteria(PSB) w isolated from samples of fertile soil, 16 colonies showed positive reaction were chosen .2- bacteria , which exhibited high phosphate clearing zone (PCZ) selected to detect their efficiencies for dissolving rock phospate and select the effective one (most potent) on the basis of highest production of phosphatase and phosphorus solubilization.3- identification of the most potent (pseudomonas aeruginosa) 4- effective environmental and nutritional factors on phosphatase production by pseudomonas aeruginosa were discussed.green-house experiment: inoculation of wheat (triticum aestivum cv.sakha 8) with either PSB and /or VAM with or without rock-P fertilization was under taken. dual inoculation with psb (pseudomonas aeruginosa) and VAM improved the dry matter yield and N and P uptake by wheat as compared to other treatments. application of psb as well as VAM increased the availability of rock phosphate to be utilized by wheat

Ventilation air methane destruction - the new challenge to the underground coal mining industry

International Nuclear Information System (INIS)

Clarke, Michael; Seddon, Duncan

2012-01-01

With the advent of 'Carbon Taxes' the carbon footprint of coal has become an economic as well as an environmental issue and the emission of methane in mine out- bye air as ventilation air methane (VAM) is a pending liability. As well as being economic and environmental concerns, VAM and VAM management have safety, social licence and operational factors that must also be addressed. The need to mitigate (oxidise) methane to produce carbon dioxide and water vapour (VAM destruction) and thus lower the Greenhouse footprint is coming to be seen as a necessary mining activity. However, there are several key issues to be addressed with present technology using high temperature (1000°C) thermal oxidisers. Emerging technology may involve a catalytic approach. This technology aims to lower the oxidation temperature and produce a more efficient combustion process. Several systems (based on both precious metals and transition metals) have been shown to operate below 400°C. An ultimate solution would be oxidation at ambient temperature, which is clearly demonstrated by the enzyme methane mono-oxygenase (MMO) which oxidises methane to methanol. However, the rate of oxidation at ambient temperature is too low and the structure of the bio-reactors required would be very large. The challenge is to marry the natural oxidation with modern catalytic approaches and achieve high rates of methane oxidation, in compact equipment, well below the methane auto-ignition temperature.

Concrete domains

OpenAIRE

Kahn, G.; Plotkin, G.D.

1993-01-01

This paper introduces the theory of a particular kind of computation domains called concrete domains. The purpose of this theory is to find a satisfactory framework for the notions of coroutine computation and sequentiality of evaluation.

A Logic for Inclusion of Administrative Domains and Administrators in Multi-domain Authorization

Science.gov (United States)

Iranmanesh, Zeinab; Amini, Morteza; Jalili, Rasool

Authorization policies for an administrative domain or a composition of multiple domains in multi-domain environments are determined by either one administrator or multiple administrators' cooperation. Several logic-based models for multi-domain environments' authorization have been proposed; however, they have not considered administrators and administrative domains in policies' representation. In this paper, we propose the syntax, proof theory, and semantics of a logic for multi-domain authorization policies including administrators and administrative domains. Considering administrators in policies provides the possibility of presenting composite administration having applicability in many collaborative applications. Indeed, administrators and administrative domains stated in policies can be used in authorization. The presented logic is based on modal logic and utilizes two calculi named the calculus of administrative domains and the calculus of administrators. It is also proved that the logic is sound. A case study is presented signifying the logic application in practical projects.

Feature-level domain adaptation

DEFF Research Database (Denmark)

Kouw, Wouter M.; Van Der Maaten, Laurens J P; Krijthe, Jesse H.

2016-01-01

-level domain adaptation (flda), that models the dependence between the two domains by means of a feature-level transfer model that is trained to describe the transfer from source to target domain. Subsequently, we train a domain-adapted classifier by minimizing the expected loss under the resulting transfer...... modeled via a dropout distribution, which allows the classiffier to adapt to differences in the marginal probability of features in the source and the target domain. Our experiments on several real-world problems show that flda performs on par with state-of-the-art domainadaptation techniques.......Domain adaptation is the supervised learning setting in which the training and test data are sampled from different distributions: training data is sampled from a source domain, whilst test data is sampled from a target domain. This paper proposes and studies an approach, called feature...

Economics of Internet interdomain interconnections

OpenAIRE

Castro Arribas, Ignacio de

2015-01-01

Aquesta tesi estudia els aspectes econòmics de la interconnexió entre Ases, identifica desafiaments que amenacen el futur d'Internet i proposa solucions per resoldre'ls. Primerament vam realitzar el primer estudi analític i empíric sobre el peering remot, un tipus emergent d'interconnexió que relaxa les limitacions geogràfiques dels Ases i facilita interconnexions a un menor cost. Després vam presentar CIPT i T4P, dos nous tipus d'interconnexions que redueixen els costos d'interconnexió entre...

Ética Médica y Sociedad Actual

Directory of Open Access Journals (Sweden)

Hernando Forero Caballero

1998-12-01

, inmutable, imperecedera, que se puede expresar por parcialidades culturales sin dejar de ser una e indivisible.