Sample records for bet specific surface

  1. Final report of CCQM-K136 measurement of porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3

    NASA Astrophysics Data System (ADS)

    Sobina, E.; Zimathis, A.; Prinz, C.; Emmerling, F.; Unger, W.; de Santis Neves, R.; Galhardo, C. E.; De Robertis, E.; Wang, H.; Mizuno, K.; Kurokawa, A.

    2016-01-01

    CCQM key comparison K-136 Measurement of porosity properties (specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous Al2O3 has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The objective of this key comparison is to compare the equivalency of the National Metrology Institutes (NMIs) and Designated Institutes (DIs) for the measurement of specific adsorption, BET specific surface area, specific pore volume and pore diameter) of nanoporous substances (sorbents, catalytic agents, cross-linkers, zeolites, etc) used in advanced technology. In this key comparison, a commercial sorbent (aluminum oxide) was supplied as a sample. Five NMIs participated in this key comparison. All participants used a gas adsorption method, here nitrogen adsorption at 77.3 K, for analysis according to the international standards ISO 15901-2 and 9277. In this key comparison, the degrees of equivalence uncertainties for specific adsorption, BET specific surface area, specific pore volume and pore diameter was established. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  2. Opposing effects of cancer-type-specific SPOP mutants on BET protein degradation and sensitivity to BET inhibitors.

    PubMed

    Janouskova, Hana; El Tekle, Geniver; Bellini, Elisa; Udeshi, Namrata D; Rinaldi, Anna; Ulbricht, Anna; Bernasocchi, Tiziano; Civenni, Gianluca; Losa, Marco; Svinkina, Tanya; Bielski, Craig M; Kryukov, Gregory V; Cascione, Luciano; Napoli, Sara; Enchev, Radoslav I; Mutch, David G; Carney, Michael E; Berchuck, Andrew; Winterhoff, Boris J N; Broaddus, Russell R; Schraml, Peter; Moch, Holger; Bertoni, Francesco; Catapano, Carlo V; Peter, Matthias; Carr, Steven A; Garraway, Levi A; Wild, Peter J; Theurillat, Jean-Philippe P

    2017-09-01

    It is generally assumed that recurrent mutations within a given cancer driver gene elicit similar drug responses. Cancer genome studies have identified recurrent but divergent missense mutations affecting the substrate-recognition domain of the ubiquitin ligase adaptor SPOP in endometrial and prostate cancers. The therapeutic implications of these mutations remain incompletely understood. Here we analyzed changes in the ubiquitin landscape induced by endometrial cancer-associated SPOP mutations and identified BRD2, BRD3 and BRD4 proteins (BETs) as SPOP-CUL3 substrates that are preferentially degraded by endometrial cancer-associated SPOP mutants. The resulting reduction of BET protein levels sensitized cancer cells to BET inhibitors. Conversely, prostate cancer-specific SPOP mutations resulted in impaired degradation of BETs, promoting their resistance to pharmacologic inhibition. These results uncover an oncogenomics paradox, whereby mutations mapping to the same domain evoke opposing drug susceptibilities. Specifically, we provide a molecular rationale for the use of BET inhibitors to treat patients with endometrial but not prostate cancer who harbor SPOP mutations.

  3. Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides lacking allergen-specific T cell epitopes reduces Bet v 1-specific T cell responses via blocking antibodies in a murine model for birch pollen allergy.

    PubMed

    Linhart, B; Narayanan, M; Focke-Tejkl, M; Wrba, F; Vrtala, S; Valenta, R

    2014-02-01

    Vaccines consisting of allergen-derived peptides lacking IgE reactivity and allergen-specific T cell epitopes bound to allergen-unrelated carrier molecules have been suggested as candidates for allergen-specific immunotherapy. To study whether prophylactic and therapeutic vaccination with carrier-bound peptides from the major birch pollen allergen Bet v 1 lacking allergen-specific T cell epitopes has influence on Bet v 1-specific T cell responses. Three Bet v 1-derived peptides, devoid of Bet v 1-specific T cell epitopes, were coupled to KLH and adsorbed to aluminium hydroxide to obtain a Bet v 1-specific allergy vaccine. Groups of BALB/c mice were immunized with the peptide vaccine before or after sensitization to Bet v 1. Bet v 1- and peptide-specific antibody responses were analysed by ELISA. T cell and cytokine responses to Bet v 1, KLH, and the peptides were studied in proliferation assays. The effects of peptide-specific and allergen-specific antibodies on T cell responses and allergic lung inflammation were studied using specific antibodies. Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides induced a Bet v 1-specific IgG antibody response without priming/boosting of Bet v 1-specific T cells. Prophylactic and therapeutic vaccination of mice with the peptide vaccine induced Bet v 1-specific antibodies which suppressed Bet v 1-specific T cell responses and allergic lung inflammation. Vaccination with carrier-bound allergen-derived peptides lacking allergen-specific T cell epitopes induces allergen-specific IgG antibodies which suppress allergen-specific T cell responses and allergic lung inflammation. © 2013 John Wiley & Sons Ltd.

  4. Isolation of a high-affinity Bet v 1-specific IgG-derived ScFv from a subject vaccinated with hypoallergenic Bet v 1 fragments.

    PubMed

    Gadermaier, E; Marth, K; Lupinek, C; Campana, R; Hofer, G; Blatt, K; Smiljkovic, D; Roder, U; Focke-Tejkl, M; Vrtala, S; Keller, W; Valent, P; Valenta, R; Flicker, S

    2018-01-09

    Recombinant hypoallergenic allergen derivatives have been used in clinical immunotherapy studies, and clinical efficacy seems to be related to the induction of blocking IgG antibodies recognizing the wild-type allergens. However, so far no treatment-induced IgG antibodies have been characterized. To clone, express, and characterize IgG antibodies induced by vaccination with two hypoallergenic recombinant fragments of the major birch pollen allergen, Bet v 1 in a nonallergic subject. A phage-displayed combinatorial single-chain fragment (ScFv) library was constructed from blood of the immunized subject and screened for Bet v 1-reactive antibody fragments. ScFvs were tested for specificity and cross-reactivity to native Bet v 1 and related pollen and food allergens, and epitope mapping was performed. Germline ancestor genes of the antibody were analyzed with the ImMunoGeneTics (IMGT) database. The affinity to Bet v 1 and cross-reactive allergens was determined by surface plasmon resonance measurements. The ability to inhibit patients' IgE binding to ELISA plate-bound allergens and allergen-induced basophil activation was assessed. A combinatorial ScFv library was obtained from the vaccinated donor after three injections with the Bet v 1 fragments. Despite being almost in germline configuration, ScFv (clone H3-1) reacted with high affinity to native Bet v 1 and homologous allergens, inhibited allergic patients' polyclonal IgE binding to Bet v 1, and partially suppressed allergen-induced basophil activation. Immunization with unfolded hypoallergenic allergen derivatives induces high-affinity antibodies even in nonallergic subjects which recognize the folded wild-type allergens and inhibit polyclonal IgE binding of allergic patients. © 2018 The Authors. Allergy Published by John Wiley & Sons Ltd.

  5. Chimeras of Bet v 1 and Api g 1 reveal heterogeneous IgE responses in patients with birch pollen allergy

    PubMed Central

    Gepp, Barbara; Lengger, Nina; Bublin, Merima; Hemmer, Wolfgang; Breiteneder, Heimo; Radauer, Christian

    2014-01-01

    Background Characterization of IgE-binding epitopes of allergens and determination of their patient-specific relevance is crucial for the diagnosis and treatment of allergy. Objective We sought to assess the contribution of specific surface areas of the major birch pollen allergen Bet v 1.0101 to binding IgE of individual patients. Methods Four distinct areas of Bet v 1 representing in total 81% of its surface were grafted onto the scaffold of its homolog, Api g 1.0101, to yield the chimeras Api-Bet-1 to Api-Bet-4. The chimeras were expressed in Escherichia coli and purified. IgE binding of 64 sera from Bet v 1–sensitized subjects with birch pollen allergy was determined by using direct ELISA. Specificity was assessed by means of inhibition ELISA. Results rApi g 1.0101, Api-Bet-1, Api-Bet-2, Api-Bet-3, and Api-Bet-4 bound IgE from 44%, 89%, 80%, 78%, and 48% of the patients, respectively. By comparing the amount of IgE binding to the chimeras and to rApi g 1.0101, 81%, 70%, 75%, and 45% of the patients showed significantly enhanced IgE binding to Api-Bet-1, Api-Bet-2, Api-Bet-3, and Api-Bet-4, respectively. The minority (8%) of the sera revealed enhanced IgE binding exclusively to a single chimera, whereas 31% showed increased IgE binding to all 4 chimeras compared with rApi g 1.0101. The chimeras inhibited up to 70% of IgE binding to rBet v 1.0101, confirming the specific IgE recognition of the grafted regions. Conclusion The Bet v 1–specific IgE response is polyclonal, and epitopes are spread across the entire Bet v 1 surface. Furthermore, the IgE recognition profile of Bet v 1 is highly patient specific. PMID:24529686

  6. Chimeras of Bet v 1 and Api g 1 reveal heterogeneous IgE responses in patients with birch pollen allergy.

    PubMed

    Gepp, Barbara; Lengger, Nina; Bublin, Merima; Hemmer, Wolfgang; Breiteneder, Heimo; Radauer, Christian

    2014-07-01

    Characterization of IgE-binding epitopes of allergens and determination of their patient-specific relevance is crucial for the diagnosis and treatment of allergy. We sought to assess the contribution of specific surface areas of the major birch pollen allergen Bet v 1.0101 to binding IgE of individual patients. Four distinct areas of Bet v 1 representing in total 81% of its surface were grafted onto the scaffold of its homolog, Api g 1.0101, to yield the chimeras Api-Bet-1 to Api-Bet-4. The chimeras were expressed in Escherichia coli and purified. IgE binding of 64 sera from Bet v 1-sensitized subjects with birch pollen allergy was determined by using direct ELISA. Specificity was assessed by means of inhibition ELISA. rApi g 1.0101, Api-Bet-1, Api-Bet-2, Api-Bet-3, and Api-Bet-4 bound IgE from 44%, 89%, 80%, 78%, and 48% of the patients, respectively. By comparing the amount of IgE binding to the chimeras and to rApi g 1.0101, 81%, 70%, 75%, and 45% of the patients showed significantly enhanced IgE binding to Api-Bet-1, Api-Bet-2, Api-Bet-3, and Api-Bet-4, respectively. The minority (8%) of the sera revealed enhanced IgE binding exclusively to a single chimera, whereas 31% showed increased IgE binding to all 4 chimeras compared with rApi g 1.0101. The chimeras inhibited up to 70% of IgE binding to rBet v 1.0101, confirming the specific IgE recognition of the grafted regions. The Bet v 1-specific IgE response is polyclonal, and epitopes are spread across the entire Bet v 1 surface. Furthermore, the IgE recognition profile of Bet v 1 is highly patient specific. Copyright © 2014 The Authors. Published by Mosby, Inc. All rights reserved.

  7. IgE and allergen-specific immunotherapy-induced IgG4 recognize similar epitopes of Bet v 1, the major allergen of birch pollen.

    PubMed

    Groh, N; von Loetzen, C S; Subbarayal, B; Möbs, C; Vogel, L; Hoffmann, A; Fötisch, K; Koutsouridou, A; Randow, S; Völker, E; Seutter von Loetzen, A; Rösch, P; Vieths, S; Pfützner, W; Bohle, B; Schiller, D

    2017-05-01

    Allergen-specific immunotherapy (AIT) with birch pollen generates Bet v 1-specific immunoglobulin (Ig)G 4 which blocks IgE-mediated hypersensitivity mechanisms. Whether IgG 4 specific for Bet v 1a competes with IgE for identical epitopes or whether novel epitope specificities of IgG 4 antibodies are developed is under debate. We sought to analyze the epitope specificities of IgE and IgG 4 antibodies from sera of patients who received AIT. 15 sera of patients (13/15 received AIT) with Bet v 1a-specific IgE and IgG 4 were analyzed. The structural arrangements of recombinant (r)Bet v 1a and rBet v 1a _11x , modified in five potential epitopes, were analyzed by circular dichroism and nuclear magnetic resonance spectroscopy. IgE binding to Bet v 1 was assessed by ELISA and mediator release assays. Competitive binding of monoclonal antibodies specific for Bet v 1a and serum IgE/IgG 4 to rBet v 1a and serum antibody binding to a non-allergenic Bet v 1-type model protein presenting an individual epitope for IgE was analyzed in ELISA and western blot. rBet v 1a _11x had a Bet v 1a - similar secondary and tertiary structure. Monomeric dispersion of rBet v 1a _11x was concentration and buffer-dependent. Up to 1500-fold increase in the EC 50 for IgE-mediated mediator release induced by rBet v 1a _11x was determined. The reduction of IgE and IgG 4 binding to rBet v 1a _11x was comparable in 67% (10/15) of sera. Bet v 1a-specific monoclonal antibodies inhibited binding of serum IgE and IgG 4 to 66.1% and 64.9%, respectively. Serum IgE and IgG 4 bound specifically to an individual epitope presented by our model protein in 33% (5/15) of sera. Patients receiving AIT develop Bet v 1a-specific IgG 4 which competes with IgE for partly identical or largely overlapping epitopes. The similarities of epitopes for IgE and IgG 4 might stimulate the development of epitope-specific diagnostics and therapeutics. © 2016 John Wiley & Sons Ltd.

  8. Optimum BET surface areas for activated carbon produced from textile sewage sludges and its application as dye removal.

    PubMed

    Kacan, Erdal

    2016-01-15

    The purpose of this experimental study is to determine optimum preparation conditions for activated carbons obtained from textile sewage sludge (TSS) for removal of dyes from aqueous solutions. The textile sewage sludge activated carbon (TSSAC) was prepared by chemical activation with potassium hydroxide using Response Surface Methodology (RSM). The most influential factor on each experimental design responses was identified via ANNOVA analysis. Based on the central composite design (CCD), quadratic model was developed to correlate the preparation variables for one response which is the Brunauer-Emmelt-Teller (BET) surface area. RSM based on a three-variable CCD was used to determine the effect of pyrolyzed temperature (400-700 °C), carbonization time (45-180 min) and KOH: weight of TSS (wt%) impregnation ratio (0.5:1-1.5:1) on BET surface area. According to the results, pyrolyzed temperature and impregnation ratio were found as the significant factors for maximizing the BET surface area. The major effect which influences the BET surface area was found as pyrolyzed temperature. Both carbonization time and impregnation ratio of KOH had no significant effect. The optimum conditions for preparing TSSAC, based on response surface and contour plots, were found as follows: pyrolyzed temperature 700 °C, carbonization time of 45 min and chemical impregnation ratio of 0.5. The maximum and optimum BET surface area of TSSAC were found as 336 m(2)/g and 310.62 m(2)/g, respectively. Synozol Blue reactive (RSB) and Setapers Yellow-Brown (P2RFL) industrial textile dyes adsorption capacities were investigated. As expected the TSSAC which has the biggest BET surface area (336 m(2)/g) adsorbed dye best. The maximum (RSB) and (P2RFL) uptake capacities were found as 8.5383 mg/g and 5.4 mg/g, respectively. The results of this study indicated the applicability of TSSAC for removing industrial dyes from aqueous solution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Thermal Desorption Analysis of Effective Specific Soil Surface Area

    NASA Astrophysics Data System (ADS)

    Smagin, A. V.; Bashina, A. S.; Klyueva, V. V.; Kubareva, A. V.

    2017-12-01

    A new method of assessing the effective specific surface area based on the successive thermal desorption of water vapor at different temperature stages of sample drying is analyzed in comparison with the conventional static adsorption method using a representative set of soil samples of different genesis and degree of dispersion. The theory of the method uses the fundamental relationship between the thermodynamic water potential (Ψ) and the absolute temperature of drying ( T): Ψ = Q - aT, where Q is the specific heat of vaporization, and a is the physically based parameter related to the initial temperature and relative humidity of the air in the external thermodynamic reservoir (laboratory). From gravimetric data on the mass fraction of water ( W) and the Ψ value, Polyanyi potential curves ( W(Ψ)) for the studied samples are plotted. Water sorption isotherms are then calculated, from which the capacity of monolayer and the target effective specific surface area are determined using the BET theory. Comparative analysis shows that the new method well agrees with the conventional estimation of the degree of dispersion by the BET and Kutilek methods in a wide range of specific surface area values between 10 and 250 m2/g.

  10. Correlation of sensitizing capacity and T-cell recognition within the Bet v 1 family

    PubMed Central

    Kitzmüller, Claudia; Zulehner, Nora; Roulias, Anargyros; Briza, Peter; Ferreira, Fatima; Faé, Ingrid; Fischer, Gottfried F.; Bohle, Barbara

    2015-01-01

    Background Bet v 1 is the main sensitizing allergen in birch pollen. Like many other major allergens, it contains an immunodominant T cell–activating region (Bet v 1142-156). Api g 1, the Bet v 1 homolog in celery, lacks the ability to sensitize and is devoid of major T-cell epitopes. Objective We analyzed the T-cell epitopes of Mal d 1, the nonsensitizing Bet v 1 homolog in apple, and assessed possible differences in uptake and antigen processing of Bet v 1, Api g 1, and Mal d 1. Methods For epitope mapping, Mal d 1–specific T-cell lines were stimulated with overlapping synthetic 12-mer peptides. The surface binding, internalization, and intracellular degradation of Bet v 1, Api g 1, and Mal d 1 by antigen-presenting cells were compared by using flow cytometry. All proteins were digested with endolysosomal extracts, and the resulting peptides were identified by means of mass spectrometry. The binding of Bet v 1142-156 and the homologous region in Mal d 1 by HLA class II molecules was analyzed in silico. Results Like Api g 1, Mal d 1 lacked dominant T-cell epitopes. The degree of surface binding and the kinetics of uptake and endolysosomal degradation of Bet v 1, Api g 1, and Mal d 1 were comparable. Endolysosomal degradation of Bet v 1 and Mal d 1 resulted in very similar fragments. The Bet v 1142-156 and Mal d 1141-155 regions showed no striking difference in their binding affinities to the most frequent HLA-DR alleles. Conclusion The sensitizing activity of different Bet v 1 homologs correlates with the presence of immunodominant T-cell epitopes. However, the presence of Bet v 1142-156 is not conferred by differential antigen processing. PMID:25670010

  11. Risk Factors for Gambling Problems on Online Electronic Gaming Machines, Race Betting and Sports Betting

    PubMed Central

    Hing, Nerilee; Russell, Alex M.; Browne, Matthew

    2017-01-01

    Growth of Internet gambling has fuelled concerns about its contribution to gambling problems. However, most online gamblers also gamble on land-based forms, which may be the source of problems for some. Studies therefore need to identify the problematic mode of gambling (online or offline) to identify those with an online gambling problem. Identifying most problematic form of online gambling (e.g., EGMs, race betting, sports betting) would also enable a more accurate examination of gambling problems attributable to a specific online gambling form. This study pursued this approach, aiming to: (1) determine demographic, behavioral and psychological risk factors for gambling problems on online EGMs, online sports betting and online race betting; (2) compare the characteristics of problematic online gamblers on each of these online forms. An online survey of 4,594 Australian gamblers measured gambling behavior, most problematic mode and form of gambling, gambling attitudes, psychological distress, substance use, help-seeking, demographics and problem gambling status. Problem/moderate risk gamblers nominating an online mode of gambling as their most problematic, and identifying EGMs (n = 98), race betting (n = 291) or sports betting (n = 181) as their most problematic gambling form, were compared to non-problem/low risk gamblers who had gambled online on these forms in the previous 12 months (n = 64, 1145 and 1213 respectively), using bivariate analyses and then logistic regressions. Problem/moderate risk gamblers on each of these online forms were then compared. Risk factors for online EGM gambling were: more frequent play on online EGMs, substance use when gambling, and higher psychological distress. Risk factors for online sports betting were being male, younger, lower income, born outside of Australia, speaking a language other than English, more frequent sports betting, higher psychological distress, and more negative attitudes toward gambling. Risk factors for

  12. Risk Factors for Gambling Problems on Online Electronic Gaming Machines, Race Betting and Sports Betting.

    PubMed

    Hing, Nerilee; Russell, Alex M; Browne, Matthew

    2017-01-01

    Growth of Internet gambling has fuelled concerns about its contribution to gambling problems. However, most online gamblers also gamble on land-based forms, which may be the source of problems for some. Studies therefore need to identify the problematic mode of gambling (online or offline) to identify those with an online gambling problem. Identifying most problematic form of online gambling (e.g., EGMs, race betting, sports betting) would also enable a more accurate examination of gambling problems attributable to a specific online gambling form. This study pursued this approach, aiming to: (1) determine demographic, behavioral and psychological risk factors for gambling problems on online EGMs, online sports betting and online race betting; (2) compare the characteristics of problematic online gamblers on each of these online forms. An online survey of 4,594 Australian gamblers measured gambling behavior, most problematic mode and form of gambling, gambling attitudes, psychological distress, substance use, help-seeking, demographics and problem gambling status. Problem/moderate risk gamblers nominating an online mode of gambling as their most problematic, and identifying EGMs ( n = 98), race betting ( n = 291) or sports betting ( n = 181) as their most problematic gambling form, were compared to non-problem/low risk gamblers who had gambled online on these forms in the previous 12 months ( n = 64, 1145 and 1213 respectively), using bivariate analyses and then logistic regressions. Problem/moderate risk gamblers on each of these online forms were then compared. Risk factors for online EGM gambling were: more frequent play on online EGMs, substance use when gambling, and higher psychological distress. Risk factors for online sports betting were being male, younger, lower income, born outside of Australia, speaking a language other than English, more frequent sports betting, higher psychological distress, and more negative attitudes toward gambling. Risk factors for

  13. The Clinical Impact of Bet v 6 in Birch Pollen-Sensitized Patients.

    PubMed

    Gellrich, Donata; Eder, Katharina; San Nicoló, Marion; Berghaus, Alexander; Gröger, Moritz

    2017-01-01

    Bet v 6, a minor birch pollen allergen, is commercially available for allergen-specific IgE antibody testing. However, there is hardly any literature on the clinical impact of Bet v 6. The aim of the present study was to analyze if testing specific IgE against Bet v 6 can add valuable benefit to the standard diagnostics of birch pollen-sensitized patients, especially in patients with unknown sensitization-eliciting allergens. Birch pollen-sensitized patients with missing IgE reactivity against Bet v 1, 2, and 4 were tested for specific IgE antibodies against Bet v 6. For comparison, an equal number of randomly selected patients with birch pollen sensitization, regardless of their individual sensitization patterns, were tested for specific anti-Bet v 6. Of 57 cases with missing reactivity against the standard birch pollen allergens, 2 patients were positive for Bet v 6. In the representative sample, 3 patients showed specific IgE against Bet v 6 - resulting in a total prevalence of 5%. None of the Bet v 6-positive patients showed allergic symptoms after exposure to birch pollen or an oral allergy syndrome. An increased prevalence of asthma and a higher degree of sensitization were the only distinctive clinical features in Bet v 6-positive patients. Among birch pollen-sensitized patients, the prevalence of specific IgE against Bet v 6 is low. Further, sensitization to Bet v 6, which shows characteristics of a panallergen, remains clinically silent. Therefore, determination of anti-Bet v 6 is not considered useful in the clinical routine. © 2017 S. Karger AG, Basel.

  14. Characterization of epitope specificities of reference antibodies used for the quantification of the birch pollen allergen Bet v 1.

    PubMed

    Brier, S; Le Mignon, M; Jain, K; Lebrun, C; Peurois, F; Kellenberger, C; Bordas-Le Floch, V; Mascarell, L; Nony, E; Moingeon, P

    2018-05-01

    Accurate allergen quantification is needed to document the consistency of allergen extracts used for immunotherapy. Herein, we characterize the epitope specificities of two monoclonal antibodies used in an ELISA for the quantification of the major birch pollen allergen Bet v 1, established as a reference by the BSP090 European project. The ability of mAbs 5B4 and 6H4 to recognize Bet v 1 isoforms was addressed by immunochromatography. The capacity of each mAb to compete with patients' IgE for binding to Bet v 1 was measured by ELISA inhibition. Epitope mapping was performed by pepscan analysis, site-directed mutagenesis, and hydrogen/deuterium exchange-mass spectrometry. The 5B4 epitope corresponds to a peptide sequence (I56-K68) overlapping with the binding sites of patients' serum IgEs. Mutation of residues P59, E60, and K65 abolishes 5B4 binding to Bet v 1 and reduces the level of IgE recognition. In contrast, 6H4 recognizes a conformational epitope lying opposite to the 5B4 binding site, involving residues located in segments I44-K55 and R70-F79. Substitution of E45 reduces the binding capacity of 6H4, confirming that it is critical for the interaction. Both mAbs interact with >90% of Bet v 1 content present in the birch pollen extract, while displaying a weak cross-reactivity with other allergens of the PR-10 family. MAbs 5B4 and 6H4 recognize structurally distinct epitopes present in the vast majority of Bet v 1 isoforms. These results support the relevance as a reference method of the Bet v 1-specific quantitative ELISA adopted by the European Pharmacopoeia. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  15. IgE, IgG4 and IgA specific to Bet v 1-related food allergens do not predict oral allergy syndrome.

    PubMed

    Guhsl, E E; Hofstetter, G; Lengger, N; Hemmer, W; Ebner, C; Fröschl, R; Bublin, M; Lupinek, C; Breiteneder, H; Radauer, C

    2015-01-01

    Birch pollen-associated plant food allergy is caused by Bet v 1-specific IgE, but presence of cross-reactive IgE to related allergens does not predict food allergy. The role of other immunoglobulin isotypes in the birch pollen-plant food syndrome has not been investigated in detail. Bet v 1-sensitized birch pollen-allergic patients (n = 35) were diagnosed for food allergy by standardized interviews, skin prick tests, prick-to-prick tests and ImmunoCAP. Concentrations of allergen-specific IgE, IgG1, IgG4 and IgA to seven Bet v 1-related food allergens were determined by ELISA. Bet v 1, Cor a 1, Mal d 1 and Pru p 1 bound IgE from all and IgG4 and IgA from the majority of sera. Immunoglobulins to Gly m 4, Vig r 1 and Api g 1.01 were detected in <65% of the sera. No significant correlation was observed between plant food allergy and increased or reduced levels of IgE, IgG1, IgG4 or IgA specific to most Bet v 1-related allergens. Api g 1-specific IgE was significantly (P = 0.01) elevated in celeriac-allergic compared with celeriac-tolerant patients. Likewise, frequencies of IgE (71% vs 15%; P = 0.01) and IgA (86% vs 38%; P = 0.04) binding to Api g 1.01 were increased. Measurements of allergen-specific immunoglobulins are not suitable for diagnosing Bet v 1-mediated plant food allergy to hazelnut and Rosaceae fruits. In contrast, IgE and IgA to the distantly related allergen Api g 1 correlate with allergy to celeriac. © 2014 The Authors. Allergy Published by John Wiley & Sons Ltd.

  16. Targeting MYCN-Driven Transcription By BET-Bromodomain Inhibition.

    PubMed

    Henssen, Anton; Althoff, Kristina; Odersky, Andrea; Beckers, Anneleen; Koche, Richard; Speleman, Frank; Schäfers, Simon; Bell, Emma; Nortmeyer, Maike; Westermann, Frank; De Preter, Katleen; Florin, Alexandra; Heukamp, Lukas; Spruessel, Annika; Astrahanseff, Kathy; Lindner, Sven; Sadowski, Natalie; Schramm, Alexander; Astorgues-Xerri, Lucile; Riveiro, Maria E; Eggert, Angelika; Cvitkovic, Esteban; Schulte, Johannes H

    2016-05-15

    Targeting BET proteins was previously shown to have specific antitumoral efficacy against MYCN-amplified neuroblastoma. We here assess the therapeutic efficacy of the BET inhibitor, OTX015, in preclinical neuroblastoma models and extend the knowledge on the role of BRD4 in MYCN-driven neuroblastoma. The efficacy of OTX015 was assessed in in vitro and in vivo models of human and murine MYCN-driven neuroblastoma. To study the effects of BET inhibition in the context of high MYCN levels, MYCN was ectopically expressed in human and murine cells. The effect of OTX015 on BRD4-regulated transcriptional pause release was analyzed using BRD4 and H3K27Ac chromatin immunoprecipitation coupled with DNA sequencing (ChIP-Seq) and gene expression analysis in neuroblastoma cells treated with OTX015 compared with vehicle control. OTX015 showed therapeutic efficacy against preclinical MYCN-driven neuroblastoma models. Similar to previously described BET inhibitors, concurrent MYCN repression was observed in OTX015-treated samples. Ectopic MYCN expression, however, did not abrogate effects of OTX015, indicating that MYCN repression is not the only target of BET proteins in neuroblastoma. When MYCN was ectopically expressed, BET inhibition still disrupted MYCN target gene transcription without affecting MYCN expression. We found that BRD4 binds to super-enhancers and MYCN target genes, and that OTX015 specifically disrupts BRD4 binding and transcription of these genes. We show that OTX015 is effective against mouse and human MYCN-driven tumor models and that BRD4 not only targets MYCN, but specifically occupies MYCN target gene enhancers as well as other genes associated with super-enhancers. Clin Cancer Res; 22(10); 2470-81. ©2015 AACR. ©2015 American Association for Cancer Research.

  17. Small-Molecule Targeting of BET Proteins in Cancer.

    PubMed

    French, C A

    2016-01-01

    BET proteins have recently become recognized for their role in a broad range of cancers and are defined by the presence of two acetyl-histone reading bromodomains and an ET domain. This family of proteins includes BRD2, BRD3, BRD4, and BRDT. BRD4 is the most-studied BET protein in cancer, and normally serves as an epigenetic reader that links active chromatin marks to transcriptional elongation through activation of RNA polymerase II. The role of BRD3 and BRD4 first became known in cancer as mutant oncoproteins fused to the p300-recruiting NUT protein in a rare aggressive subtype of squamous cell cancer known as NUT midline carcinoma (NMC). BET inhibitors are acetyl-histone mimetics that specifically bind BET bromodomains, competitively inhibiting its engagement with chromatin. The antineoplastic effects of BET inhibitors were first demonstrated in NMC and have since been shown to be effective at inhibiting the growth of many different cancers, particularly acute leukemia. BET inhibitors have also been instrumental as tool compounds that have demonstrated the key role of BRD4 in driving NMC and non-NMC cancer growth. Many clinical trials enrolling patients with hematologic and solid tumors are ongoing, with encouraging preliminary findings. BET proteins BRD2, BRD3, and BRD4 are expressed in nearly all cells of the body, so there are concerns of toxicity with BET inhibitors, as well as the development of resistance. Toxicity and resistance may be overcome by combining BET inhibitors with other targeted inhibitors, or through the use of novel BET inhibitor derivatives. © 2016 Elsevier Inc. All rights reserved.

  18. BET surface area distributions in polar stream sediments: Implications for silicate weathering in a cold-arid environment

    USGS Publications Warehouse

    Marra, Kristen R.; Elwood Madden, Megan E; Soreghan, Gerilyn S.; Hall, Brenda L

    2014-01-01

    BET surface area values are critical for quantifying the amount of potentially reactive sediments available for chemical weathering and ultimately, prediction of silicate weathering fluxes. BET surface area values of fine-grained (<62.5 μm) sediment from the hyporheic zone of polar glacial streams in the McMurdo Dry Valleys, Antarctica (Wright and Taylor Valleys) exhibit a wide range (2.5–70.6 m2/g) of surface area values. Samples from one (Delta Stream, Taylor Valley) of the four sampled stream transects exhibit high values (up to 70.6 m2/g), which greatly exceed surface area values from three temperate proglacial streams (0.3–12.1 m2/g). Only Clark stream in Wright Valley exhibits a robust trend with distance, wherein surface area systematically decreases (and particle size increases) in the mud fraction downstream, interpreted to reflect rapid dissolution processes in the weathering environment. The remaining transects exhibit a range in variability in surface area distributions along the length of the channel, likely related to variations in eolian input to exposed channel beds, adjacent snow drifts, and to glacier surfaces, where dust is trapped and subsequently liberated during summer melting. Additionally, variations in stream discharge rate, which mobilizes sediment in pulses and influences water:rock ratios, the origin and nature of the underlying drift material, and the contribution of organic acids may play significant roles in the production and mobilization of high-surface area sediment. This study highlights the presence of sediments with high surface area in cold-based glacier systems, which influences models of chemical denudation rates and the impact of glacial systems on the global carbon cycle.

  19. Application of Consistency Criteria To Calculate BET Areas of Micro- And Mesoporous Metal-Organic Frameworks.

    PubMed

    Gómez-Gualdrón, Diego A; Moghadam, Peyman Z; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

    2016-01-13

    Metal-organic frameworks (MOFs) can exhibit exceptionally high surface areas, which are experimentally estimated by applying the BET theory to measured nitrogen isotherms. The Brunauer, Emmett, and Teller (BET)-estimated nitrogen monolayer loading is thus converted to a "BET area," but the meaning of MOF BET areas remains under debate. Recent emphasis has been placed on the usage of four so-called "BET consistency criteria." Using these criteria and simulated nitrogen isotherms for perfect crystals, we calculated BET areas for graphene and 25 MOFs having different pore-size distributions. BET areas were compared with their corresponding geometrically calculated, nitrogen-accessible surface areas (NASAs). Analysis of simulation snapshots elucidated the contributions of "pore-filling" and "monolayer-formation" to the nitrogen adsorption loadings in different MOF pores, revealing the origin of inaccuracies in BET-calculated monolayer loadings, which largely explain discrepancies between BET areas and NASAs. We also find that even if all consistency criteria are satisfied, the BET calculation can significantly overestimate the true monolayer loading, especially in MOFs combining mesopores (d ≥ 20 Å) and large micropores (d = 10-20 Å), due to the overlap of pore-filling and monolayer-formation regimes of these two kinds of pores. While it is not always possible to satisfy all consistency criteria, it is critical to minimize the deviation from these criteria during BET range selection to consistently compare BET areas of different MOFs and for comparing simulated and experimental BET areas of a given MOF. To accurately assess the quality of a MOF sample, it is best to compare experimental BET areas with simulated BET areas rather than with calculated NASAs.

  20. Nitration of the Pollen Allergen Bet v 1.0101 Enhances the Presentation of Bet v 1-Derived Peptides by HLA-DR on Human Dendritic Cells

    PubMed Central

    Mutschlechner, Sonja; Ferreira, Fatima; Lackner, Peter; Bohle, Barbara; Fischer, Gottfried F.; Vogt, Anne B.; Duschl, Albert

    2012-01-01

    Nitration of pollen derived allergens can occur by NO2 and ozone in polluted air and it has already been shown that nitrated major birch (Betula verrucosa) pollen allergen Bet v 1.0101 (Bet v 1) exhibits an increased potency to trigger an immune response. However, the mechanisms by which nitration might contribute to the induction of allergy are still unknown. In this study, we assessed the effect of chemically induced nitration of Bet v 1 on the generation of HLA-DR associated peptides. Human dendritic cells were loaded with unmodified Bet v 1 or nitrated Bet v 1, and the naturally processed HLA-DR associated peptides were subsequently identified by liquid chromatography-mass spectrometry. Nitration of Bet v 1 resulted in enhanced presentation of allergen-derived HLA-DR-associated peptides. Both the copy number of Bet v 1 derived peptides as well as the number of nested clusters was increased. Our study shows that nitration of Bet v 1 alters antigen processing and presentation via HLA-DR, by enhancing both the quality and the quantity of the Bet v 1-specific peptide repertoire. These findings indicate that air pollution can contribute to allergic diseases and might also shed light on the analogous events concerning the nitration of self-proteins. PMID:22348091

  1. On the Spur of the Moment: Intrinsic Predictors of Impulse Sports Betting.

    PubMed

    Hing, Nerilee; Li, En; Vitartas, Peter; Russell, Alex M T

    2018-06-01

    Betting on impulse, without thoughtful consideration, research or informed decision-making, may cause financial and other harms and lead to the development of gambling problems. Impulse betting undermines responsible consumption of gambling because it reflects self-regulatory failure, impaired control, unreflective decision-making and betting more than planned. In this paper we define impulse gambling and report on a study that aimed to understand more about the intrinsic characteristics of sports bettors who have a greater tendency to bet on impulse. Specifically, the study aimed to identify behavioural, psychological and socio-demographic predictors of impulse sports betting. A sample of 1816 Australian sports bettors completed an online survey that measured the proportion of their bets placed on impulse both before and during sporting events, as well as bets that were researched and planned in advance. Impulse betting was common, accounting for nearly one-half of all past-year sports bets by respondents. Over three-quarters of respondents had placed one or more impulse bets in the last year and one in seven respondents had made all of their sports bets on impulse. More impulsive sports bettors were characterised as having higher trait impulsiveness, higher problem gambling severity, more frequent sports betting and a shorter history of sports betting. They favoured betting on in-match contingencies instead of overall match outcomes. While health promotion strategies are needed to discourage impulse betting, research into contextual factors that arouse urges to bet would also provide direction for harm minimisation measures that help consumers to resist impulsive betting decisions.

  2. Isolation of Mal d 1 and Api g 1 - specific recombinant antibodies from mouse IgG Fab fragment libraries - Mal d 1-specific antibody exhibits cross-reactivity against Bet v 1.

    PubMed

    Haka, Jaana; Niemi, Merja H; Iljin, Kristiina; Reddy, Vanga Siva; Takkinen, Kristiina; Laukkanen, Marja-Leena

    2015-05-27

    Around 3-5% of the population suffer from IgE-mediated food allergies in Western countries and the number of food-allergenic people is increasing. Individuals with certain pollen allergies may also suffer from a sensitisation to proteins in the food products. As an example a person sensitised to the major birch pollen allergen, Bet v 1, is often sensitised to its homologues, such as the major allergens of apple, Mal d 1, and celery, Api g 1, as well. Development of tools for the reliable, sensitive and quick detection of allergens present in various food products is essential for allergic persons to prevent the consumption of substances causing mild and even life-threatening immune responses. The use of monoclonal antibodies would ensure the specific detection of the harmful food content for a sensitised person. Mouse IgG antibody libraries were constructed from immunised mice and specific recombinant antibodies for Mal d 1 and Api g 1 were isolated from the libraries by phage display. More detailed characterisation of the resulting antibodies was carried out using ELISA, SPR experiments and immunoprecipitation assays. The allergen-specific Fab fragments exhibited high affinity towards the target recombinant allergens. Furthermore, the Fab fragments also recognised native allergens from natural sources. Interestingly, isolated Mal d 1-specific antibody bound also to Bet v 1, the main allergen eliciting the cross-reactivity syndrome between the birch pollen and apple. Despite the similarities in Api g 1 and Bet v 1 tertiary structures, the isolated Api g 1-specific antibodies showed no cross-reactivity to Bet v 1. Here, high-affinity allergen-specific recombinant antibodies were isolated with interesting binding properties. With further development, these antibodies can be utilised as tools for the specific and reliable detection of allergens from different consumable products. This study gives new preliminary insights to elucidate the mechanism behind the pollen

  3. Targeting BET bromodomain proteins in solid tumors

    PubMed Central

    Sahai, Vaibhav; Redig, Amanda J.; Collier, Katharine A.; Eckerdt, Frank D.; Munshi, Hidayatullah G.

    2016-01-01

    There is increasing interest in inhibitors targeting BET (bromodomain and extra-terminal) proteins because of the association between this family of proteins and cancer progression. BET inhibitors were initially shown to have efficacy in hematologic malignancies; however, a number of studies have now shown that BET inhibitors can also block progression of non-hematologic malignancies. In this Review, we summarize the efficacy of BET inhibitors in select solid tumors; evaluate the role of BET proteins in mediating resistance to current targeted therapies; and consider potential toxicities of BET inhibitors. We also evaluate recently characterized mechanisms of resistance to BET inhibitors; summarize ongoing clinical trials with these inhibitors; and discuss potential future roles of BET inhibitors in patients with solid tumors. PMID:27283767

  4. T-bet promotes the accumulation of encephalitogenic Th17 cells in the CNS.

    PubMed

    Grifka-Walk, Heather M; Segal, Benjamin M

    2017-03-15

    T-bet enhances the encephalitogenicity of myelin-reactive CD4 + T cells, however its mechanism of action is unknown. In this study we show that T-bet confers a competitive advantage for the accumulation of IL-23 conditioned Th17 effector cells in the central nervous system (CNS). Impaired migration of T-bet deficient Th17 cells to the CNS is associated with altered expression of adhesion molecules and chemokine receptors on their cell surface. Our data suggest that therapeutic targeting of T-bet in individuals with Th17-mediated autoimmune demyelinating disease may inhibit inflammatory infiltration of the CNS and, hence, clinical exacerbations. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Gas adsorption on commercial magnesium stearate: Effects of degassing conditions on nitrogen BET surface area and isotherm characteristics.

    PubMed

    Lapham, Darren P; Lapham, Julie L

    2017-09-15

    Commercial grades of magnesium stearate have been analysed by nitrogen adsorption having been pre-treated at temperatures between 30°C and 110°C and in the as-received state. Characteristics of nitrogen adsorption/desorption isotherms are assessed through the linearity of low relative pressure isotherm data and the BET transform plot together with the extent of isotherm hysteresis. Comparison is made between thermal gravimetric analysis and mass loss on drying. Features of gas adsorption isotherms considered atypical are identified and possible causes presented. It is shown that atypical isotherm features and issues of applying BET theory to the calculation of S BET are linked to the presence of hydrated water and that these depend on the hydration state: being more pronounced for the di-hydrate than the mono-hydrate. Dehydration reduces the extent of atypical features. S BET of a mono-hydrate sample is 5.6m 2 g -1 and 3.2m 2 g -1 at 40°C and 100°C degassing respectively but 23.9m 2 g 1 and 5.9m 2 g -1 for di-hydrate containing samples under comparable degassing. Di-hydrated samples also show S BET >15m 2 g 1 , BET C-values <7 and BET correlation coefficients <0.98 before dehydration. Possible mechanisms for atypical isotherms are critically discussed together with the suitability of applying BET theory to nitrogen adsorption data. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Betting patterns for sports and races: a longitudinal analysis of online wagering in Australia.

    PubMed

    Gainsbury, Sally M; Russell, Alex

    2015-03-01

    Online wagering is increasing in popularity as it is easily accessible through websites which market these services widely. However, few studies have examined online betting based on actual behavioural data. This paper describes the results of an analysis of 2,522,299 bets placed with an Australian online wagering operator over a 1-year period. The majority of bets placed were for a win (45.31 %) and were placed on races (86.74 %) or sports (11.29 %). Sports betting was dominated by ball sports, reflecting popular interest in these events. More than three-quarters (77.63 %) of the bets were losses and there was large variation in bet size between bet types and events bet on although average bets were higher than in previously reported studies. The most popular bets placed to win, had a relatively high rate of losses and lowest average returns, which may reflect less sophisticated betting behaviour. More specific handicap and total bets were placed by fewer customers, but were larger bets with the greatest returns. Similarly, bets placed on less popular sporting events had greater average returns potentially reflecting greater customer sophistication and knowledge raising the possibility of a proportion of bettors being more 'skilled'. As the first paper to analyze the types of bets placed on events and outcomes the results support the notion that wagering is an entertainment activity, and the majority of customers are motivated by factors other than simply winning money.

  7. Betting is Loving and Bettors are Predators: A Conceptual Metaphor Approach to Online Sports Betting Advertising.

    PubMed

    Lopez-Gonzalez, Hibai; Guerrero-Solé, Frederic; Estévez, Ana; Griffiths, Mark

    2017-10-30

    The legalisation of online gambling in multiple territories has caused a growth in the exposure of consumers to online sports betting (OSB) advertising. While some efforts have been made to understand the visible structure of betting promotional messages, little is known about the latent components of OSB advertisements. The present study sought to address this issue by examining the metaphorical conceptualisation of OSB advertising. A sample of Spanish and British television OSB advertisements from 2014 to 2016 was analysed (N = 133). Following Lakoff and Johnson's conceptual metaphor theory, four main structural metaphors that shaped how OSB advertising can be understood were identified: betting as (1) an act of love, (2) a market, (3) a sport, and (4) a natural environment. In general, these metaphors, which were found widely across 29 different betting brands, facilitated the perception of bettors as active players, with an executive role in the sport events bet upon, and greater control over bet outcomes.

  8. The Betting Odds Rating System: Using soccer forecasts to forecast soccer.

    PubMed

    Wunderlich, Fabian; Memmert, Daniel

    2018-01-01

    Betting odds are frequently found to outperform mathematical models in sports related forecasting tasks, however the factors contributing to betting odds are not fully traceable and in contrast to rating-based forecasts no straightforward measure of team-specific quality is deducible from the betting odds. The present study investigates the approach of combining the methods of mathematical models and the information included in betting odds. A soccer forecasting model based on the well-known ELO rating system and taking advantage of betting odds as a source of information is presented. Data from almost 15.000 soccer matches (seasons 2007/2008 until 2016/2017) are used, including both domestic matches (English Premier League, German Bundesliga, Spanish Primera Division and Italian Serie A) and international matches (UEFA Champions League, UEFA Europe League). The novel betting odds based ELO model is shown to outperform classic ELO models, thus demonstrating that betting odds prior to a match contain more relevant information than the result of the match itself. It is shown how the novel model can help to gain valuable insights into the quality of soccer teams and its development over time, thus having a practical benefit in performance analysis. Moreover, it is argued that network based approaches might help in further improving rating and forecasting methods.

  9. The Betting Odds Rating System: Using soccer forecasts to forecast soccer

    PubMed Central

    Memmert, Daniel

    2018-01-01

    Betting odds are frequently found to outperform mathematical models in sports related forecasting tasks, however the factors contributing to betting odds are not fully traceable and in contrast to rating-based forecasts no straightforward measure of team-specific quality is deducible from the betting odds. The present study investigates the approach of combining the methods of mathematical models and the information included in betting odds. A soccer forecasting model based on the well-known ELO rating system and taking advantage of betting odds as a source of information is presented. Data from almost 15.000 soccer matches (seasons 2007/2008 until 2016/2017) are used, including both domestic matches (English Premier League, German Bundesliga, Spanish Primera Division and Italian Serie A) and international matches (UEFA Champions League, UEFA Europe League). The novel betting odds based ELO model is shown to outperform classic ELO models, thus demonstrating that betting odds prior to a match contain more relevant information than the result of the match itself. It is shown how the novel model can help to gain valuable insights into the quality of soccer teams and its development over time, thus having a practical benefit in performance analysis. Moreover, it is argued that network based approaches might help in further improving rating and forecasting methods. PMID:29870554

  10. T-bet-dependent NKp46+ innate lymphoid cells regulate the onset of TH17-induced neuroinflammation.

    PubMed

    Kwong, Brandon; Rua, Rejane; Gao, Yuanyuan; Flickinger, John; Wang, Yan; Kruhlak, Michael J; Zhu, Jinfang; Vivier, Eric; McGavern, Dorian B; Lazarevic, Vanja

    2017-10-01

    The transcription factor T-bet has been associated with increased susceptibility to systemic and organ-specific autoimmunity, but the mechanism by which T-bet expression promotes neuroinflammation remains unknown. In this study, we demonstrate a cardinal role of T-bet-dependent NKp46 + innate lymphoid cells (ILCs) in the initiation of CD4 + T H 17-mediated neuroinflammation. Loss of T-bet specifically in NKp46 + ILCs profoundly impaired the ability of myelin-reactive T H 17 cells to invade central nervous system (CNS) tissue and protected the mice from autoimmunity. T-bet-dependent NKp46 + ILCs localized in the meninges and acted as chief coordinators of meningeal inflammation by inducing the expression of proinflammatory cytokines, chemokines and matrix metalloproteinases, which together facilitated T cell entry into CNS parenchyma. Our findings uncover a detrimental role of T-bet-dependent NKp46 + ILCs in the development of CNS autoimmune disease.

  11. T-bet-dependent NKp46+ innate lymphoid cells regulate the onset of TH17-induced neuroinflammation

    PubMed Central

    Kwong, Brandon; Rua, Rejane; Gao, Yuanyuan; Flickinger, John; Wang, Yan; Kruhlak, Michael J.; Zhu, Jinfang; Vivier, Eric; McGavern, Dorian B.; Lazarevic, Vanja

    2017-01-01

    The transcription factor T-bet has been linked to increased susceptibility to systemic and organ-specific autoimmunity, but the mechanism by which T-bet expression promotes neuroinflammation remains unknown. In this study, we demonstrate a cardinal role for T-bet-dependent NKp46+ innate lymphoid cells (ILCs) in the initiation of CD4+ TH17-mediated neuroinflammation. Loss of T-bet specifically in NKp46+ ILCs profoundly impaired the ability of myelin-reactive TH17 cells to invade the central nervous system (CNS) tissue and protected the mice from autoimmunity. T-bet-dependent NKp46+ ILCs were localized in the meninges and acted as chief coordinators of meningeal inflammation by inducing the expression of pro-inflammatory cytokines, chemokines and matrix metalloproteinases, which in a concerted fashion facilitated T cell entry into CNS parenchyma. Our findings uncover a detrimental role of T-bet-dependent NKp46+ ILCs in the development of CNS autoimmune disease. PMID:28805812

  12. Bet v 1-specific T-cell receptor/forkhead box protein 3 transgenic T cells suppress Bet v 1-specific T-cell effector function in an activation-dependent manner.

    PubMed

    Schmetterer, Klaus G; Haiderer, Daniela; Leb-Reichl, Victoria M; Neunkirchner, Alina; Jahn-Schmid, Beatrice; Küng, Hans J; Schuch, Karina; Steinberger, Peter; Bohle, Barbara; Pickl, Winfried F

    2011-01-01

    Regulatory T (Treg) cells establish and maintain tolerance to self-antigens and many foreign antigens, such as allergens, by suppressing effector T-cell proliferation and function. We have previously shown that human T-cell receptor (TCR) αβ-chains specific for allergen-derived epitopes confer allergen specificity on peripheral blood T cells of individuals with and without allergy. To study the feasibility of generating allergen-specific human Treg cells by retroviral transduction of a transcription unit encoding forkhead box protein 3 (FOXP3) and allergen-specific TCR αβ-chains. cDNAs encoding the α and β-chains of a Bet v 1(142-153)-specific TCR (TCR alpha variable region 6/TCR beta variable region 20) and human FOXP3 were linked via picornaviral 2A sequences and expressed as single translational unit from an internal ribosomal entry site-green fluorescence protein-containing retroviral vector. Retrovirally transduced peripheral blood T cells were tested for expression of transgenes, Treg phenotype, and regulatory capacity toward allergen-specific effector T cells. Transduced T cells displayed a Treg phenotype with clear-cut upregulation of CD25, CD39, and cytotoxic T-lymphocyte antigen 4. The transduced cells were hyporesponsive in cytokine production and secretion and, like naturally occurring Treg cells, did not proliferate after antigen-specific or antigen-mimetic stimulation. However, proliferation was inducible upon exposure to exogenous IL-2. In coculture experiments, TRAV6(+)TRBV20(+)FOXP3(+) transgenic T cells, unlike FOXP3(+) single transgenic T cells or naturally occurring Treg cells, highly significantly suppressed T cell cytokine production and proliferation of corresponding allergen-specific effector T cells in an allergen-specific, dose-dependent manner. We demonstrate a transgenic approach to engineer human allergen-specific Treg cells that exert their regulatory function in an activation-dependent manner. Customized Treg cells might become

  13. RVX-297- a novel BD2 selective inhibitor of BET bromodomains

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kharenko, Olesya A., E-mail: olesya@zenithepigenetics.com; Gesner, Emily M.; Patel, Reena G.

    Bromodomains are epigenetic readers that specifically bind to the acetyl lysine residues of histones and transcription factors. Small molecule BET bromodomain inhibitors can disrupt this interaction which leads to potential modulation of several disease states. Here we describe the binding properties of a novel BET inhibitor RVX-297 that is structurally related to the clinical compound RVX-208, currently undergoing phase III clinical trials for the treatment of cardiovascular diseases, but is distinctly different in its biological and pharmacokinetic profiles. We report that RVX-297 preferentially binds to the BD2 domains of the BET bromodomain and Extra Terminal (BET) family of protein. Wemore » demonstrate the differential binding modes of RVX-297 in BD1 and BD2 domains of BRD4 and BRD2 using X-ray crystallography, and describe the structural differences driving the BD2 selective binding of RVX-297. The isothermal titration calorimetry (ITC) data illustrate the related differential thermodynamics of binding of RVX-297 to single as well as dual BET bromodomains. - Highlights: • A novel inhibitor of BET bromodomains, RVX-297 is described. • The differential binding modes of RVX-297 in BD1 and BD2 domains of BRD4 and BRD2 using X-ray crystallography are described. • RVX-297 preferentially binds to the BD2 domains of the BET bromodomains. • The structural and thermodynamic properties of the BD2 selective binding of RVX-297 are characterized.« less

  14. STS-8 bet results

    NASA Technical Reports Server (NTRS)

    Findlay, J. T.; Kelly, G. M.; Heck, M. L.; Mcconnell, J. G.

    1983-01-01

    The final Best Estimate Trajectory (BET) products, i.e., the reconstructed trajectory, the Extended BET, AEROBET and MMLE input files, generated for the eighth NASA Space Shuttle flight are documented. The reconstructed trajectory (inertial BET) for this Challenger flight, the first night landing is discussed. State (position, velocity, and attitude) plus three accelerometer scale factors were determined from fitting the Guam S-band data, seven C-band passes, and pseudo Doppler and altimeter during rollout on Runway 22. The anchor epoch utilized for the batch weighted-least-squares determination was Sept. 5, 1983 7h1m50s.0 (25310 GMT seconds). The spacecraft altitude at epoch is approx. 617 kft. IMU2 data were selected for the reconstruction.

  15. Ligand Recognition of the Major Birch Pollen Allergen Bet v 1 is Isoform Dependent

    PubMed Central

    Seutter von Loetzen, Christian; Jacob, Thessa; Hartl-Spiegelhauer, Olivia; Vogel, Lothar; Schiller, Dirk; Spörlein-Güttler, Cornelia; Schobert, Rainer; Vieths, Stefan; Hartl, Maximilian Johannes; Rösch, Paul

    2015-01-01

    Each spring millions of patients suffer from allergies when birch pollen is released into the air. In most cases, the major pollen allergen Bet v 1 is the elicitor of the allergy symptoms. Bet v 1 comes in a variety of isoforms that share virtually identical conformations, but their relative concentrations are plant-specific. Glycosylated flavonoids, such as quercetin-3-O-sophoroside, are the physiological ligands of Bet v 1, and here we found that three isoforms differing in their allergenic potential also show an individual, highly specific binding behaviour for the different ligands. This specificity is driven by the sugar moieties of the ligands rather than the flavonols. While the influence of the ligands on the allergenicity of the Bet v 1 isoforms may be limited, the isoform and ligand mixtures add up to a complex and thus individual fingerprint of the pollen. We suggest that this mixture is not only acting as an effective chemical sunscreen for pollen DNA, but may also play an important role in recognition processes during pollination. PMID:26042900

  16. Roles of Three Transporters, CbcXWV, BetT1, and BetT3, in Pseudomonas aeruginosa Choline Uptake for Catabolism ▿ †

    PubMed Central

    Malek, Adel A.; Chen, Chiliang; Wargo, Matthew J.; Beattie, Gwyn A.; Hogan, Deborah A.

    2011-01-01

    Pseudomonas aeruginosa uses the quaternary amine choline as a carbon source, osmoprotectant, and macromolecular precursor. The importance of choline in P. aeruginosa physiology is highlighted by the presence of multiple known and putative choline transporters encoded within its genome. This report describes the relative roles of three choline transporters, the ABC transporter CbcXWV and two symporters, BetT1 and BetT3, in P. aeruginosa growth on choline under osmotic conditions that are physiologically relevant to eukaryotic hosts. The increased lag phases exhibited by the ΔbetT1 and ΔbetT1 ΔbetT3 mutants relative to the wild type upon transfer to medium with choline as a sole carbon source suggested roles for BetT1 and BetT3 in cells newly exposed to choline. BetT3 and CbcXWV, but not BetT1, were sufficient to support growth on choline. betT1 and betT3 expression was regulated by the repressor BetI and choline, whereas cbcXWV expression was induced by the activator GbdR and glycine betaine. The data support a model in which, upon transfer to a choline-based medium, the glycine betaine derived from choline taken up by BetT1 and BetT3 promotes subsequent GbdR-mediated cbcXWV induction. Furthermore, growth data indicated that the relative contributions of each transporter varied under different conditions, as BetT1 and CbcXWV were the primary choline transporters under hypo-osmolar conditions whereas BetT3 was the major choline transporter under hyperosmolar conditions. This work represents the first systematic approach to unravel the mechanisms of choline uptake in P. aeruginosa, which has the most complex bacterial choline uptake systems characterized to date. PMID:21478341

  17. Modes of response to environmental change and the elusive empirical evidence for bet hedging

    PubMed Central

    Simons, Andrew M.

    2011-01-01

    Uncertainty is a problem not only in human decision-making, but is a prevalent quality of natural environments and thus requires evolutionary response. Unpredictable natural selection is expected to result in the evolution of bet-hedging strategies, which are adaptations to long-term fluctuating selection. Despite a recent surge of interest in bet hedging, its study remains mired in conceptual and practical difficulties, compounded by confusion over what constitutes evidence for its existence. Here, I attempt to resolve misunderstandings about bet hedging and its relationship with other modes of response to environmental change, identify the challenges inherent to its study and assess the state of existing empirical evidence. The variety and distribution of plausible bet-hedging traits found across 16 phyla in over 100 studies suggest their ubiquity. Thus, bet hedging should be considered a specific mode of response to environmental change. However, the distribution of bet-hedging studies across evidence categories—defined according to potential strength—is heavily skewed towards weaker categories, underscoring the need for direct appraisals of the adaptive significance of putative bet-hedging traits in nature. PMID:21411456

  18. BET inhibitors in cancer therapeutics: a patent review.

    PubMed

    Ghoshal, Anirban; Yugandhar, D; Srivastava, Ajay Kumar

    2016-01-01

    Inhibition of Bromodomain and Extra Terminal (BET) proteins is an emerging approach for developing advanced cancer therapeutics. In 2015, at least thirty patents have been published for developing cancer chemotherapeutics by targeting BET. Currently there are seven small molecule BET inhibitors in various stages of clinical trials for the development of anti-cancer drugs. Important patents focusing on development of BET inhibitors as potential cancer therapeutics published in 2015 have been covered. The reports are presented together with a review of the related structural chemical space. This review mainly focuses on the therapeutic applications, chemical class and structural modifications along with the molecules currently in clinical trials. BET sub-family proteins are one of the emerging targets to develop anti-cancer agents. Although many research groups have demonstrated the rationality of BET inhibition to combat cancer, a detailed molecular study needs to be performed to investigate the affected biological pathways. Selectivity among BET proteins should be kept in mind while developing BET inhibitors. In-silico molecular modelling studies can also provide valuable information for designing selective BET inhibitors towards anti-cancer drug discovery and development.

  19. What do children observe and learn from televised sports betting advertisements? A qualitative study among Australian children.

    PubMed

    Pitt, Hannah; Thomas, Samantha L; Bestman, Amy; Daube, Mike; Derevensky, Jeffrey

    2017-12-01

    To explore children's awareness of sports betting advertising and how this advertising may influence children's attitudes, product knowledge and desire to try sports betting. Semi-structured qualitative interviews were conducted with 48 children (8-16 years) from Melbourne, Victoria. The interview schedule explored children's recall and interpretations of sports betting advertising, strategies within advertisements that may appeal to children, children's product knowledge and understanding of betting terminology, and factors that may encourage gambling. Interviews were transcribed and thematic analysis was conducted. Children recalled in detail sports betting advertisements that they had seen, with humour the most engaging appeal strategy. They were also able to describe other specific appeal strategies and link these strategies to betting brands. Many children described how advertisements demonstrated how someone would place a bet, with some children recalling the detailed technical language associated with betting. Children had detailed recall of sports betting advertisements and an extensive knowledge of sports betting products and terminology. Implications for public health: To protect children from the potential harms associated with sports betting, governments should consider changing regulations and implementing evidence-based education campaigns to counter the positive messages children receive from the sports betting industry. © 2017 The Authors.

  20. NMR resonance assignments of a hypoallergenic isoform of the major birch pollen allergen Bet v 1.

    PubMed

    Ahammer, Linda; Grutsch, Sarina; Wallner, Michael; Ferreira, Fatima; Tollinger, Martin

    2017-10-01

    In Northern America and Europe a great number of people are suffering from birch pollen allergy and pollen related food allergies. The trigger for these immunological reactions is the 17.5 kDa major birch pollen allergen Bet v 1, which belongs to the family of PR-10 (pathogenesis-related) proteins. In nature, Bet v 1 occurs as a mixture of various isoforms that possess different immunological properties despite their high sequence identities. Bet v 1.0102 (Bet v 1d), which is investigated here, is a hypoallergenic isoform of Bet v 1 and a potential candidate for allergen-specific immunotherapy. We assigned the backbone and side chain 1 H, 13 C and 15 N resonances of this protein and predicted its secondary structure. The NMR-chemical shift data indicate that Bet v 1.0102 is composed of three α-helices and a seven stranded β-sheet, in agreement with the known structure of the hyperallergenic isoform Bet v 1.0101 (Bet v 1a). Our resonance assignments create the foundation for detailed characterization of the dynamic properties of Bet v 1 isoforms by NMR relaxation measurements.

  1. CXCR6 marks a novel subset of T-bet(lo)Eomes(hi) natural killer cells residing in human liver.

    PubMed

    Stegmann, Kerstin A; Robertson, Francis; Hansi, Navjyot; Gill, Upkar; Pallant, Celeste; Christophides, Theodoros; Pallett, Laura J; Peppa, Dimitra; Dunn, Claire; Fusai, Giuseppe; Male, Victoria; Davidson, Brian R; Kennedy, Patrick; Maini, Mala K

    2016-05-23

    Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56(bright)CD16-CD57-), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6- fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bet(hi)Eomes(lo)(CXCR6-) and T-bet(lo)Eomes(hi)(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bet(hi)Eomes(lo), suggesting its lineage was closer to CXCR6- peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-bet(lo)Eomes(hi) NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity.

  2. BET bromodomain proteins are required for glioblastoma cell proliferation.

    PubMed

    Pastori, Chiara; Daniel, Mark; Penas, Clara; Volmar, Claude-Henry; Johnstone, Andrea L; Brothers, Shaun P; Graham, Regina M; Allen, Bryce; Sarkaria, Jann N; Komotar, Ricardo J; Wahlestedt, Claes; Ayad, Nagi G

    2014-04-01

    Epigenetic proteins have recently emerged as novel anticancer targets. Among these, bromodomain and extra terminal domain (BET) proteins recognize lysine-acetylated histones, thereby regulating gene expression. Newly described small molecules that inhibit BET proteins BRD2, BRD3, and BRD4 reduce proliferation of NUT (nuclear protein in testis)-midline carcinoma, multiple myeloma, and leukemia cells in vitro and in vivo. These findings prompted us to determine whether BET proteins may be therapeutic targets in the most common primary adult brain tumor, glioblastoma (GBM). We performed NanoString analysis of GBM tumor samples and controls to identify novel therapeutic targets. Several cell proliferation assays of GBM cell lines and stem cells were used to analyze the efficacy of the drug I-BET151 relative to temozolomide (TMZ) or cell cycle inhibitors. Lastly, we performed xenograft experiments to determine the efficacy of I-BET151 in vivo. We demonstrate that BRD2 and BRD4 RNA are significantly overexpressed in GBM, suggesting that BET protein inhibition may be an effective means of reducing GBM cell proliferation. Disruption of BRD4 expression in glioblastoma cells reduced cell cycle progression. Similarly, treatment with the BET protein inhibitor I-BET151 reduced GBM cell proliferation in vitro and in vivo. I-BET151 treatment enriched cells at the G1/S cell cycle transition. Importantly, I-BET151 is as potent at inhibiting GBM cell proliferation as TMZ, the current chemotherapy treatment administered to GBM patients. Since I-BET151 inhibits GBM cell proliferation by arresting cell cycle progression, we propose that BET protein inhibition may be a viable therapeutic option for GBM patients suffering from TMZ resistant tumors.

  3. BET bromodomain proteins are required for glioblastoma cell proliferation

    PubMed Central

    Pastori, Chiara; Daniel, Mark; Penas, Clara; Volmar, Claude-Henry; Johnstone, Andrea L; Brothers, Shaun P; Graham, Regina M; Allen, Bryce; Sarkaria, Jann N; Komotar, Ricardo J; Wahlestedt, Claes; Ayad, Nagi G

    2014-01-01

    Epigenetic proteins have recently emerged as novel anticancer targets. Among these, bromodomain and extra terminal domain (BET) proteins recognize lysine-acetylated histones, thereby regulating gene expression. Newly described small molecules that inhibit BET proteins BRD2, BRD3, and BRD4 reduce proliferation of NUT (nuclear protein in testis)-midline carcinoma, multiple myeloma, and leukemia cells in vitro and in vivo. These findings prompted us to determine whether BET proteins may be therapeutic targets in the most common primary adult brain tumor, glioblastoma (GBM). We performed NanoString analysis of GBM tumor samples and controls to identify novel therapeutic targets. Several cell proliferation assays of GBM cell lines and stem cells were used to analyze the efficacy of the drug I-BET151 relative to temozolomide (TMZ) or cell cycle inhibitors. Lastly, we performed xenograft experiments to determine the efficacy of I-BET151 in vivo. We demonstrate that BRD2 and BRD4 RNA are significantly overexpressed in GBM, suggesting that BET protein inhibition may be an effective means of reducing GBM cell proliferation. Disruption of BRD4 expression in glioblastoma cells reduced cell cycle progression. Similarly, treatment with the BET protein inhibitor I-BET151 reduced GBM cell proliferation in vitro and in vivo. I-BET151 treatment enriched cells at the G1/S cell cycle transition. Importantly, I-BET151 is as potent at inhibiting GBM cell proliferation as TMZ, the current chemotherapy treatment administered to GBM patients. Since I-BET151 inhibits GBM cell proliferation by arresting cell cycle progression, we propose that BET protein inhibition may be a viable therapeutic option for GBM patients suffering from TMZ resistant tumors. PMID:24496381

  4. STS-40 descent BET products: Development and results

    NASA Technical Reports Server (NTRS)

    Oakes, Kevin F.; Wood, James S.; Findlay, John T.

    1991-01-01

    Descent Best Estimate Trajectory (BET) Data were generated for the final Orbiter Experiments Flight, STS-40. This report discusses the actual development of these post-flight products: the inertial BET, the Extended BET, and the Aerodynamic BET. Summary results are also included. The inertial BET was determined based on processing Tracking and Data Relay Satellite (TDRSS) coherent Doppler data in conjunction with observations from eleven C-band stations, to include data from the Kwajalein Atoll and the usual California coastal radars, as well as data from five cinetheodolite cameras in the vicinity of the runways at EAFB. The anchor epoch utilized for the trajectory reconstruction was 53,904 Greenwich Mean Time (GMT) seconds which corresponds to an altitude at epoch of approximately 708 kft. Atmospheric data to enable development of an Extended BET for this mission were upsurped from the JSC operational post-flight BET. These data were evaluated based on Space Shuttle-derived considerations as well as model comparisons. The Aerodynamic BET includes configuration information, final mass properties, and both flight-determined and predicted aerodynamic performance estimates. The predicted data were based on the final pre-operational databook, updated to include flight determined incrementals based on an earlier ensemble of flights. Aerodynamic performance comparisons are presented and correlated versus statistical results based on twenty-two previous missions.

  5. Characterization of the T-cell response to Dau c 1, the Bet v 1-homolog in carrot.

    PubMed

    Zulehner, N; Nagl, B; Briza, P; Roulias, A; Ballmer-Weber, B; Zlabinger, G J; Ferreira, F; Bohle, B

    2017-02-01

    In contrast to other Bet v 1-related food allergens, the major carrot allergen, Dau c 1, has been suggested to induce food allergy independently from Bet v 1. As T cells are crucial in the sensitization process, we sought to characterize the T-cell response to Dau c 1 and its cross-reactivity with Bet v 1. Dau c 1-specific T-cell lines (TCL) and clones (TCC) established from PBMC of birch pollen-allergic patients with carrot allergy were analyzed for reactivity to Bet v 1, epitope specificity, allergen-induced cytokine secretion, and expression of integrins α4β7 and α4β1, critical for gut and lung homing, respectively. mRNA expression of GATA3 and Tbet was analyzed in sorted CD3 + CD4 + CFSE low cells proliferating upon stimulation of PBMC with Dau c 1 or Bet v 1. Dau c 1 was incubated with endolysosomal proteases, and the resulting fragments were identified by mass spectrometry. Among 14 distinct T-cell-activating regions, Dau c 1 139-153 was recognized by 55% of the patients. Only 6 of 15 (40%) Dau c 1-specific TCL and 9 of 21 (43%) TCC reacted with Bet v 1. Bet v 1-nonreactive TCC were mainly Th1-like and showed a higher expression of the integrin β7 and a significantly lower expression of the integrin β1 than Bet v 1-positive TCC. A Th1-like response was also detected in Dau c 1-reactive CD3 + CD4 + CFSE low cells. Full-length Dau c 1 was still detectable after 48 h of endolysosomal degradation. Proteolytic fragments of Dau c 1 matched its T-cell-activating regions. Dau c 1 displays several characteristics of sensitizing allergens, namely a major T-cell-activating region, low susceptibility to endolysosomal degradation, and induction of a Bet v 1-independent T-cell response. These cellular insights confirm that the major carrot allergen has a special status among Bet v 1-related food allergens. © 2016 The Authors. Allergy Published by John Wiley & Sons Ltd.

  6. STS-13 (41-C) BET products

    NASA Technical Reports Server (NTRS)

    Findlay, J. T.; Kelly, G. M.; Mcconnell, J. G.; Heck, M. L.

    1984-01-01

    Results from the STS-13 (41-C) Shuttle entry flight are presented. The entry trajectory was reconstructed from an altitude of 700 kft through rollout on Runway 17 at EAFB. The anchor epoch utilized was April 13, 1984 13(h)1(m)30.(s)0 (46890(s).0) GMT. The final reconstructed inertial trajectory for this flight is BT13M23 under user catalog 169750N. Trajectory reconstruction and Extended BET development are discussed in Section 1 and 2, respectively. The NOAA totem-pole atmosphere extracted from the JSC/TRW BET was adopted in the development of the LaRC Extended BET, namely ST13BET/UN=274885C. The Aerodynamic BET was generated on physical nine track reel NC0728 with a duplicate copy on NC0740 for back-up. Plots of the more relevant parameters from the AEROBET are presented in Section 3. Section 4 discusses the MMLE input files created for STS-13. Appendices are attached which present spacecraft and physical constants utilized (Appendix A), residuals by station and data type (Appendix B), a two second spaced listing of trajectory and air data parameters (Appendix C), and input and output source products for archival (Appendix D).

  7. Using bets to reveal people's opinions on climate change

    NASA Astrophysics Data System (ADS)

    Lewandowsky, S.; Risbey, J.; Boslough, M.

    2016-12-01

    A long-standing means of revealing people's actual preferences, for example regarding economic and political issues, involves gambles and bets. People tend to place bets when they are confident of their opinions, and they tend to avoid them when they are not confident of their opinions. We survey the reluctance of climate contrarians to engage in bets with scientists, and we review the historical and likely future fate of various bets on climate change. We show that for the last few decades, most bets placed on the climate would have been lost by contrarians and would have been won by people who endorse the mainstream scientific position. We relate bets and gambles to actuarial information on climate change and propose ways in which the scientific community can use markets of bets as a tool to resolve ambiguities and to communicate scientific facts with an appropriate level of certainty to the public.

  8. Double-bromo and extraterminal (BET) domain proteins regulate dendrite morphology and mechanosensory function

    PubMed Central

    Bagley, Joshua A.; Yan, Zhiqiang; Zhang, Wei; Wildonger, Jill

    2014-01-01

    A complex array of genetic factors regulates neuronal dendrite morphology. Epigenetic regulation of gene expression represents a plausible mechanism to control pathways responsible for specific dendritic arbor shapes. By studying the Drosophila dendritic arborization (da) neurons, we discovered a role of the double-bromodomain and extraterminal (BET) family proteins in regulating dendrite arbor complexity. A loss-of-function mutation in the single Drosophila BET protein encoded by female sterile 1 homeotic [fs(1)h] causes loss of fine, terminal dendritic branches. Moreover, fs(1)h is necessary for the induction of branching caused by a previously identified transcription factor, Cut (Ct), which regulates subtype-specific dendrite morphology. Finally, disrupting fs(1)h function impairs the mechanosensory response of class III da sensory neurons without compromising the expression of the ion channel NompC, which mediates the mechanosensitive response. Thus, our results identify a novel role for BET family proteins in regulating dendrite morphology and a possible separation of developmental pathways specifying neural cell morphology and ion channel expression. Since the BET proteins are known to bind acetylated histone tails, these results also suggest a role of epigenetic histone modifications and the “histone code,” in regulating dendrite morphology. PMID:25184680

  9. Double-bromo and extraterminal (BET) domain proteins regulate dendrite morphology and mechanosensory function.

    PubMed

    Bagley, Joshua A; Yan, Zhiqiang; Zhang, Wei; Wildonger, Jill; Jan, Lily Yeh; Jan, Yuh Nung

    2014-09-01

    A complex array of genetic factors regulates neuronal dendrite morphology. Epigenetic regulation of gene expression represents a plausible mechanism to control pathways responsible for specific dendritic arbor shapes. By studying the Drosophila dendritic arborization (da) neurons, we discovered a role of the double-bromodomain and extraterminal (BET) family proteins in regulating dendrite arbor complexity. A loss-of-function mutation in the single Drosophila BET protein encoded by female sterile 1 homeotic [fs(1)h] causes loss of fine, terminal dendritic branches. Moreover, fs(1)h is necessary for the induction of branching caused by a previously identified transcription factor, Cut (Ct), which regulates subtype-specific dendrite morphology. Finally, disrupting fs(1)h function impairs the mechanosensory response of class III da sensory neurons without compromising the expression of the ion channel NompC, which mediates the mechanosensitive response. Thus, our results identify a novel role for BET family proteins in regulating dendrite morphology and a possible separation of developmental pathways specifying neural cell morphology and ion channel expression. Since the BET proteins are known to bind acetylated histone tails, these results also suggest a role of epigenetic histone modifications and the "histone code," in regulating dendrite morphology. © 2014 Bagley et al.; Published by Cold Spring Harbor Laboratory Press.

  10. Spatial variability of specific surface area of arable soils in Poland

    NASA Astrophysics Data System (ADS)

    Sokolowski, S.; Sokolowska, Z.; Usowicz, B.

    2012-04-01

    Evaluation of soil spatial variability is an important issue in agrophysics and in environmental research. Knowledge of spatial variability of physico-chemical properties enables a better understanding of several processes that take place in soils. In particular, it is well known that mineralogical, organic, as well as particle-size compositions of soils vary in a wide range. Specific surface area of soils is one of the most significant characteristics of soils. It can be not only related to the type of soil, mainly to the content of clay, but also largely determines several physical and chemical properties of soils and is often used as a controlling factor in numerous biological processes. Knowledge of the specific surface area is necessary in calculating certain basic soil characteristics, such as the dielectric permeability of soil, water retention curve, water transport in the soil, cation exchange capacity and pesticide adsorption. The aim of the present study is two-fold. First, we carry out recognition of soil total specific surface area patterns in the territory of Poland and perform the investigation of features of its spatial variability. Next, semivariograms and fractal analysis are used to characterize and compare the spatial variability of soil specific surface area in two soil horizons (A and B). Specific surface area of about 1000 samples was determined by analyzing water vapor adsorption isotherms via the BET method. The collected data of the values of specific surface area of mineral soil representatives for the territory of Poland were then used to describe its spatial variability by employing geostatistical techniques and fractal theory. Using the data calculated for some selected points within the entire territory and along selected directions, the values of semivariance were determined. The slope of the regression line of the log-log plot of semi-variance versus the distance was used to estimate the fractal dimension, D. Specific surface area

  11. Heuristic and analytic processing in online sports betting.

    PubMed

    d'Astous, Alain; Di Gaspero, Marc

    2015-06-01

    This article presents the results of two studies that examine the occurrence of heuristic (i.e., intuitive and fast) and analytic (i.e., deliberate and slow) processes among people who engage in online sports betting on a regular basis. The first study was qualitative and was conducted with a convenience sample of 12 regular online sports gamblers who described the processes by which they arrive at a sports betting decision. The results of this study showed that betting online on sports events involves a mix of heuristic and analytic processes. The second study consisted in a survey of 161 online sports gamblers where performance in terms of monetary gains, experience in online sports betting, propensity to collect and analyze relevant information prior to betting, and use of bookmaker odds were measured. This study showed that heuristic and analytic processes act as mediators of the relationship between experience and performance. The findings stemming of these two studies give some insights into gamblers' modes of thinking and behaviors in an online sports betting context and show the value of the dual mediation process model for research that looks at gambling activities from a judgment and decision making perspective.

  12. Size-Dependent Specific Surface Area of Nanoporous Film Assembled by Core-Shell Iron Nanoclusters

    DOE PAGES

    Antony, Jiji; Nutting, Joseph; Baer, Donald R.; ...

    2006-01-01

    Nmore » anoporous films of core-shell iron nanoclusters have improved possibilities for remediation, chemical reactivity rate, and environmentally favorable reaction pathways. Conventional methods often have difficulties to yield stable monodispersed core-shell nanoparticles. We produced core-shell nanoclusters by a cluster source that utilizes combination of Fe target sputtering along with gas aggregations in an inert atmosphere at 7 ∘ C . Sizes of core-shell iron-iron oxide nanoclusters are observed with transmission electron microscopy (TEM). The specific surface areas of the porous films obtained from Brunauer-Emmett-Teller (BET) process are size-dependent and compared with the calculated data.« less

  13. Vig r 6, the cytokinin-specific binding protein from mung bean (Vigna radiata) sprouts, cross-reacts with Bet v 1-related allergens and binds IgE from birch pollen allergic patients’ sera

    PubMed Central

    Guhsl, Eva Elisabeth; Hofstetter, Gerlinde; Hemmer, Wolfgang; Ebner, Christof; Vieths, Stefan; Vogel, Lothar; Breiteneder, Heimo; Radauer, Christian

    2014-01-01

    Scope Birch pollen associated allergy to mung bean sprouts is caused by cross-reactivity between the birch pollen allergen Bet v 1 and the mung bean allergen Vig r 1. We aimed to determine the allergenicity of the cytokinin-specific binding protein from mung bean (Vig r 6), another allergen related to Bet v 1 with only 31% sequence identity. Methods and results Bet v 1, Gly m 4, Vig r 1, and Vig r 6 were produced in Escherichia coli. In an ELISA, 73 and 32% of Bet v 1-sensitized birch-allergic patients’ sera (n = 60) showed IgE binding to Vig r 1 and Vig r 6, respectively. Of 19 patients who reported allergic reactions or had positive prick-to-prick tests to mung bean sprouts, 79% showed IgE binding to Vig r 1 and 63% showed IgE binding to Vig r 6. Bet v 1 completely inhibited IgE binding to both mung bean allergens. Vig r 6 showed partial cross-reactivity with Vig r 1 and activated basophils sensitized with mung bean allergic patients’ sera. Conclusion We demonstrated IgE cross-reactivity despite low sequence identity between Vig r 6 and other Bet v 1-related allergens. Thus, IgE binding to Vig r 6 may contribute to birch pollinosis-associated mung bean sprout allergy. PMID:23996905

  14. Intrinsic BET inhibitor resistance in SPOP-mutated prostate cancer is mediated by BET protein stabilization and AKT-mTORC1 activation.

    PubMed

    Zhang, Pingzhao; Wang, Dejie; Zhao, Yu; Ren, Shancheng; Gao, Kun; Ye, Zhenqing; Wang, Shangqian; Pan, Chun-Wu; Zhu, Yasheng; Yan, Yuqian; Yang, Yinhui; Wu, Di; He, Yundong; Zhang, Jun; Lu, Daru; Liu, Xiuping; Yu, Long; Zhao, Shimin; Li, Yao; Lin, Dong; Wang, Yuzhuo; Wang, Liguo; Chen, Yu; Sun, Yinghao; Wang, Chenji; Huang, Haojie

    2017-09-01

    Bromodomain and extraterminal domain (BET) protein inhibitors are emerging as promising anticancer therapies. The gene encoding the E3 ubiquitin ligase substrate-binding adaptor speckle-type POZ protein (SPOP) is the most frequently mutated in primary prostate cancer. Here we demonstrate that wild-type SPOP binds to and induces ubiquitination and proteasomal degradation of BET proteins (BRD2, BRD3 and BRD4) by recognizing a degron motif common among them. In contrast, prostate cancer-associated SPOP mutants show impaired binding to BET proteins, resulting in decreased proteasomal degradation and accumulation of these proteins in prostate cancer cell lines and patient specimens and causing resistance to BET inhibitors. Transcriptome and BRD4 cistrome analyses reveal enhanced expression of the GTPase RAC1 and cholesterol-biosynthesis-associated genes together with activation of AKT-mTORC1 signaling as a consequence of BRD4 stabilization. Our data show that resistance to BET inhibitors in SPOP-mutant prostate cancer can be overcome by combination with AKT inhibitors and further support the evaluation of SPOP mutations as biomarkers to guide BET-inhibitor-oriented therapy in patients with prostate cancer.

  15. Fusion proteins of flagellin and the major birch pollen allergen Bet v 1 show enhanced immunogenicity, reduced allergenicity, and intrinsic adjuvanticity.

    PubMed

    Kitzmüller, Claudia; Kalser, Julia; Mutschlechner, Sonja; Hauser, Michael; Zlabinger, Gerhard J; Ferreira, Fatima; Bohle, Barbara

    2018-01-01

    Recombinant fusion proteins of flagellin and antigens have been demonstrated to induce strong innate and adaptive immune responses. Such fusion proteins can enhance the efficacy of allergen-specific immunotherapy. We sought to characterize different fusion proteins of flagellin and the major birch pollen allergen Bet v 1 for suitability as allergy vaccines. A truncated version of flagellin (NtCFlg) was genetically fused to the N- or C-terminus of Bet v 1. Toll-like receptor (TLR) 5 binding was assessed with HEK293 cells expressing TLR5. Upregulation of CD40, CD80, CD83, and CD86 on monocyte-derived dendritic cells from allergic patients was analyzed by using flow cytometry. The T cell-stimulatory capacity of the fusion proteins was assessed with naive and Bet v 1-specific T cells. IgE binding was tested in inhibition ELISAs and basophil activation tests. Mice were immunized with the fusion proteins in the absence and presence of aluminum hydroxide. Cellular and antibody responses were monitored. Murine antibodies were tested for blocking capacity in basophil activation tests. Both fusion proteins matured monocyte-derived dendritic cells through TLR5. Compared with Bet v 1, the fusion proteins showed stronger T cell-stimulatory and reduced IgE-binding capacity and induced murine Bet v 1-specific antibodies in the absence of aluminum hydroxide. However, only antibodies induced by means of immunization with NtCFlg fused to the C-terminus of Bet v 1 inhibited binding of patients' IgE antibodies to Bet v 1. Bet v 1-flagellin fusion proteins show enhanced immunogenicity, reduced allergenicity, and intrinsic adjuvanticity and thus represent promising vaccines for birch pollen allergen-specific immunotherapy. However, the sequential order of allergen and adjuvant within a fusion protein determines its immunologic characteristics. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  16. Modulation of allergic immune responses by mucosal application of recombinant lactic acid bacteria producing the major birch pollen allergen Bet v 1.

    PubMed

    Daniel, C; Repa, A; Wild, C; Pollak, A; Pot, B; Breiteneder, H; Wiedermann, U; Mercenier, A

    2006-07-01

    Probiotic lactic acid bacteria (LAB) are able to modulate the host immune system and clinical trials have demonstrated that specific strains have the capacity to reduce allergic symptoms. Therefore, we aimed to evaluate the potential of recombinant LAB producing the major birch pollen allergen Bet v 1 for mucosal vaccination against birch pollen allergy. Recombinant Bet v 1-producing Lactobacillus plantarum and Lactococcus lactis strains were constructed. Their immunogenicity was compared with purified Bet v 1 by subcutaneous immunization of mice. Intranasal application of the live recombinant strains was performed to test their immunomodulatory potency in a mouse model of birch pollen allergy. Bet v 1 produced by the LAB was recognized by monoclonal anti-Bet v 1 and IgE antibodies from birch pollen-allergic patients. Systemic immunization with the recombinant strains induced significantly lower IgG1/IgG2a ratios compared with purified Bet v 1. Intranasal pretreatment led to reduced allergen-specific IgE vs enhanced IgG2a levels and reduced interleukin (IL)-5 production of splenocytes in vitro, indicating a shift towards non-allergic T-helper-1 (Th1) responses. Airway inflammation, i.e. eosinophils and IL-5 in lung lavages, was reduced using either Bet v 1-producing or control strains. Allergen-specific secretory IgA responses were enhanced in lungs and intestines after pretreatment with only the Bet v 1-producing strains. Mucosal vaccination with live recombinant LAB, leading to a shift towards non-allergic immune responses along with enhanced allergen-specific mucosal IgA levels offers a promising approach to prevent systemic and local allergic immune responses.

  17. Does the uptake of wagering inducements predict impulse betting on sport?

    PubMed

    Hing, Nerilee; Russell, Alex M T; Li, En; Vitartas, Peter

    2018-03-01

    Background and aims Marketing inducements for addictive products, such as wagering, can prompt impulse purchasing by triggering consumption reminders, urges, and cravings. Wagering inducements incentivize betting by providing bonus bets, money-back guarantees, deposits into betting accounts, and discounts. Their promotion during sporting events, push marketing efforts directed at consumers, and ease of uptake at the point-of-sale, may trigger betting on impulse. This study examined whether the uptake of wagering inducements predicted impulse betting on sport. Methods Australian sports bettors (N = 1,813) completed an online survey measuring their proportion of planned bets, impulse bets before match commencement, and impulse bets during play; frequency of using wagering inducements; and several psychological, behavioral, and demographic variables. Results More frequent users of wagering inducements had a greater tendency to place impulse in-play bets, which were also predicted by problem gambling, higher buying impulsiveness, higher frequency of watching sports, younger age, and higher educational status. Sports bettors with a greater tendency to place impulse bets before match commencement also tended to have higher buying impulsiveness and to be younger, but they used inducements less frequently, and tended to be female, less-educated and non-problem, moderate risk, or problem gamblers. Discussion and conclusions Uptake of wagering inducements appeared to be particularly effective in stimulating impulse in-play betting among problem gamblers and frequent sports viewers. These results suggest that a more cautious approach to the regulation of both in-play bets and wagering inducements may be required to better protect young adults from gambling problems and harm.

  18. Vig r 6, the cytokinin-specific binding protein from mung bean (Vigna radiata) sprouts, cross-reacts with Bet v 1-related allergens and binds IgE from birch pollen allergic patients' sera.

    PubMed

    Guhsl, Eva Elisabeth; Hofstetter, Gerlinde; Hemmer, Wolfgang; Ebner, Christof; Vieths, Stefan; Vogel, Lothar; Breiteneder, Heimo; Radauer, Christian

    2014-03-01

    Birch pollen associated allergy to mung bean sprouts is caused by cross-reactivity between the birch pollen allergen Bet v 1 and the mung bean allergen Vig r 1. We aimed to determine the allergenicity of the cytokinin-specific binding protein from mung bean (Vig r 6), another allergen related to Bet v 1 with only 31% sequence identity. Bet v 1, Gly m 4, Vig r 1, and Vig r 6 were produced in Escherichia coli. In an ELISA, 73 and 32% of Bet v 1-sensitized birch-allergic patients' sera (n = 60) showed IgE binding to Vig r 1 and Vig r 6, respectively. Of 19 patients who reported allergic reactions or had positive prick-to-prick tests to mung bean sprouts, 79% showed IgE binding to Vig r 1 and 63% showed IgE binding to Vig r 6. Bet v 1 completely inhibited IgE binding to both mung bean allergens. Vig r 6 showed partial cross-reactivity with Vig r 1 and activated basophils sensitized with mung bean allergic patients' sera. We demonstrated IgE cross-reactivity despite low sequence identity between Vig r 6 and other Bet v 1-related allergens. Thus, IgE binding to Vig r 6 may contribute to birch pollinosis-associated mung bean sprout allergy. © 2013 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Who decides who has won the bet? Total and Anthropogenic Warming Indices

    NASA Astrophysics Data System (ADS)

    Haustein, K.; Allen, M. R.; Otto, F. E. L.; Schmidt, A.; Frame, D. J.; Forster, P.; Matthews, D.

    2016-12-01

    An extension of the idea of betting markets as a means of revealing opinions about future climate are climate policies indexed to geophysical indicators: for example, to ensure net zero global carbon dioxide emissions by the time anthropogenic warming reaches 1.5 degrees above pre-industrial, given about 1 degree of warming already, emissions must fall, on average, by 20% of their current value for every tenth of a degree of anthropogenic warming from now on. In principle, policies conditioned on some measure of attributable warming are robust to uncertainty in the global climate response: the risk of a higher or lower response than expected is borne by those affected by climate change mitigation policy rather than those affected by climate change impacts, as is the case with emission targets for specific years based on "current understanding" of the response. To implement any indexed policy, or to agree payout terms for any bet on future climate, requires consensus on the definition of the index: how is it calculated, and who is responsible for releasing it? The global mean surface temperature of the current decade relative to pre-industrial may vary by 0.1 degree or more depending on precisely what is measured, what is defined as pre-industrial, and the treatment of regions with sparse data coverage in earlier years. Indices defined using different conventions, however, are all expected to evolve very similarly over the coming decades, so agreeing on a conservative, traceable index such as HadCRUT is more important than debating the "true" global temperature. A more important question is whether indexed policies and betting markets should focus on total warming, including natural and anthropogenic drivers and internal variability, or an Anthropogenic Warming Index (AWI) representing an unbiased estimate of warming attributable to human influence to date. We propose a simple AWI based solely on observed temperatures and global natural and anthropogenic forcing

  20. B cells expressing the transcription factor T-bet drive lupus-like autoimmunity

    PubMed Central

    Rubtsov, Anatoly V.; Thurman, Joshua M.; Mennona, Johanna M.; Kappler, John W.; Marrack, Philippa

    2017-01-01

    B cells contribute to multiple aspects of autoimmune disorders and may play a role in triggering disease. Thus, targeting B cells may be a promising strategy for treating autoimmune disorders. Better understanding of the B cell subsets that are responsible for the development of autoimmunity will be critical for developing efficient therapies. Here we have reported that B cells expressing the transcription factor T-bet promote the rapid appearance of autoantibodies and germinal centers in spontaneous murine models of systemic lupus erythematosus (SLE). Conditional deletion of T-bet from B cells impaired the formation of germinal centers and mitigated the development of kidney damage and rapid mortality in SLE mice. B cell–specific deletion of T-bet was also associated with lower activation of both B cells and T cells. Taken together, our results suggest that targeting T-bet–expressing B cells may be a potential target for therapy for autoimmune diseases. PMID:28240602

  1. Folded or Not? Tracking Bet v 1 Conformation in Recombinant Allergen Preparations

    PubMed Central

    Seutter von Loetzen, Christian; Schweimer, Kristian; Bellinghausen, Iris; Treudler, Regina; Simon, Jan C.; Vogel, Lothar; Völker, Elke; Randow, Stefanie; Reuter, Andreas; Rösch, Paul; Vieths, Stefan; Holzhauser, Thomas; Schiller, Dirk

    2015-01-01

    Background Recombinant Bet v 1a (rBet v 1a) has been used in allergy research for more than three decades, including clinical application of so-called hypoallergens. Quantitative IgE binding to rBet v 1a depends on its native protein conformation, which might be compromised upon heterologous expression, purification, or mutational engineering of rBet v 1a. Objective To correlate experimental/theoretical comparisons of IgE binding of defined molar ratios of folded/misfolded recombinant Bet v 1a variants and to determine accuracy and precision of immuno- and physicochemical assays routinely used to assess the quality of recombinant allergen preparations. Methods rBet v 1a and its misfolded variant rBet v 1aS112P/R145P were heterologously expressed and purified from Escherichia coli. Structural integrities and oligomerisation of the recombinant allergens were evaluated by 1H-nuclear magnetic resonance (1H-NMR), circular dichroism (CD) spectroscopy, and dynamic light scattering (DLS). IgE binding of defined combinations of rBet v 1a and rBet v 1aS112P/R145P was assessed using immunoblotting (IB), enzyme-linked immunosorbent assay (ELISA) and mediator release (MR) of humanized rat basophilic leukemia cells sensitized with serum IgE of subjects allergic to birch pollen. Experimental and theoretically expected results of the analyses were compared. Results 1H-NMR spectra of rBet v 1a and rBet v 1aS112P/R145P demonstrate a native and highly disordered protein conformations, respectively. The CD spectra suggested typical alpha-helical and beta-sheet secondary structure content of rBet v 1a and random coil for rBet v 1aS112P/R145P. The hydrodynamic radii (RH) of 2.49 ± 0.39 nm (rBet v 1a) and 3.1 ± 0.56 nm (rBet v 1aS112P/R145P) showed monomeric dispersion of both allergens in solution. Serum IgE of birch pollen allergic subjects bound to 0.1% rBet v 1a in the presence of 99.9% of non-IgE binding rBet v 1aS112P/R145P. Immunoblot analysis overestimated, whereas ELISA and

  2. Structure of palmitoylated BET3: insights into TRAPP complex assembly and membrane localization

    PubMed Central

    Turnbull, Andrew P; Kümmel, Daniel; Prinz, Bianka; Holz, Caterina; Schultchen, Jeffrey; Lang, Christine; Niesen, Frank H; Hofmann, Klaus-Peter; Delbrück, Heinrich; Behlke, Joachim; Müller, Eva-Christina; Jarosch, Ernst; Sommer, Thomas; Heinemann, Udo

    2005-01-01

    BET3 is a component of TRAPP, a complex involved in the tethering of transport vesicles to the cis-Golgi membrane. The crystal structure of human BET3 has been determined to 1.55-Å resolution. BET3 adopts an α/β-plait fold and forms dimers in the crystal and in solution, which predetermines the architecture of TRAPP where subunits are present in equimolar stoichiometry. A hydrophobic pocket within BET3 buries a palmitate bound through a thioester linkage to cysteine 68. BET3 and yeast Bet3p are palmitoylated in recombinant yeast cells, the mutant proteins BET3 C68S and Bet3p C80S remain unmodified. Both BET3 and BET3 C68S are found in membrane and cytosolic fractions of these cells; in membrane extractions, they behave like tightly membrane-associated proteins. In a deletion strain, both Bet3p and Bet3p C80S rescue cell viability. Thus, palmitoylation is neither required for viability nor sufficient for membrane association of BET3, which may depend on protein–protein contacts within TRAPP or additional, yet unidentified modifications of BET3. A conformational change may facilitate palmitoyl extrusion from BET3 and allow the fatty acid chain to engage in intermolecular hydrophobic interactions. PMID:15692564

  3. Understanding persuasive attributes of sports betting advertisements: A conjoint analysis of selected elements.

    PubMed

    Hing, Nerilee; Vitartas, Peter; Lamont, Matthew

    2017-12-01

    Background and aims Despite recent growth in sports betting advertising, minimal research has examined the influence of different advertising message attributes on betting attitudes and behaviors. This study aimed to identify which attributes of sports betting advertisements most engage attention, interest, desire and likelihood of betting among non-problem, low-risk, moderate-risk, and problem gamblers. Methods A novel approach utilizing an experimental design incorporating conjoint analysis examined the effects of: three message formats (commentary, on-screen display, and studio crossover); four appeals (neutral, jovial, ease of placing the bet, and sense of urgency); three types of presenters (match presenter, sports betting operator, and attractive non-expert female presenter); and four bet types (traditional, exotic key event, risk-free, and micro-bet). A professional film company using paid actors produced 20 mock television advertisements simulating typical gambling messages based on the conjoint approach. These were embedded into an online survey of 611 Australian adults. Results The most attention-grabbing attributes were type of presenter and type of bet. The attractive non-expert female presenter gained more attention from all gambler groups than other presenters. The type of bet was most persuasive in converting attention into likely betting among all gambler groups, with the risk-free bet being much more persuasive than other bet types. Problem gamblers were distinct by their greater attraction to in-play micro-bets. Discussion and conclusion Given the potential for incentivized bets offering financial inducements and for in-play micro-bets to undermine harm minimization and consumer protection, regulators and wagering operators should reconsider whether these bet types are consistent with their responsible gambling objectives.

  4. FI schedules and persistence at gambling in the U.K. betting office.

    PubMed Central

    Dickerson, M G

    1979-01-01

    This study reports on the direct observations of customers in two U.K. betting offices gambling on horse and dog races. These observations revealed that bets were more frequently placed in the last minutes just prior to the start (the OFF), and that this was caused by high-frequency gamblers (customers who had eight or more bets in a session) consistently placing their bets in the last two minutes prior to the OFF. Low-frequency gamblers (three or fewer bets/session) avoided this time period placing their bets earlier, or after the OFF, i.e., on a later race. It was argued that the betting behavior of the "gamblers" could not be explained either in terms of "skillful betting" or solely in terms of variable ratio schedules but was more adequately accounted for in terms of an interval schedule. It was further suggested that time-based schedules might be of heuristic value in generally understanding persistence at gambling while losing. PMID:511799

  5. 18 CFR 706.209 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Gambling, betting, and lotteries. 706.209 Section 706.209 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.209 Gambling, betting...

  6. 18 CFR 706.209 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Gambling, betting, and lotteries. 706.209 Section 706.209 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.209 Gambling, betting...

  7. 18 CFR 706.209 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Gambling, betting, and lotteries. 706.209 Section 706.209 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.209 Gambling, betting...

  8. 18 CFR 706.209 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Gambling, betting, and lotteries. 706.209 Section 706.209 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.209 Gambling, betting...

  9. 18 CFR 706.209 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Gambling, betting, and lotteries. 706.209 Section 706.209 Conservation of Power and Water Resources WATER RESOURCES COUNCIL EMPLOYEE RESPONSIBILITIES AND CONDUCT Conduct and Responsibilities of Employees § 706.209 Gambling, betting...

  10. Selective BET bromodomain inhibition as an antifungal therapeutic strategy

    PubMed Central

    Mietton, Flore; Ferri, Elena; Champleboux, Morgane; Zala, Ninon; Maubon, Danièle; Zhou, Yingsheng; Harbut, Mike; Spittler, Didier; Garnaud, Cécile; Courçon, Marie; Chauvel, Murielle; d'Enfert, Christophe; Kashemirov, Boris A.; Hull, Mitchell; Cornet, Muriel; McKenna, Charles E.; Govin, Jérôme; Petosa, Carlo

    2017-01-01

    Invasive fungal infections cause significant morbidity and mortality among immunocompromised individuals, posing an urgent need for new antifungal therapeutic strategies. Here we investigate a chromatin-interacting module, the bromodomain (BD) from the BET family of proteins, as a potential antifungal target in Candida albicans, a major human fungal pathogen. We show that the BET protein Bdf1 is essential in C. albicans and that mutations inactivating its two BDs result in a loss of viability in vitro and decreased virulence in mice. We report small-molecule compounds that inhibit C. albicans Bdf1 with high selectivity over human BDs. Crystal structures of the Bdf1 BDs reveal binding modes for these inhibitors that are sterically incompatible with the human BET-binding pockets. Furthermore, we report a dibenzothiazepinone compound that phenocopies the effects of a Bdf1 BD-inactivating mutation on C. albicans viability. These findings establish BET inhibition as a promising antifungal therapeutic strategy and identify Bdf1 as an antifungal drug target that can be selectively inhibited without antagonizing human BET function. PMID:28516956

  11. BET Bromodomain Inhibition Releases the Mediator Complex from Select cis-Regulatory Elements.

    PubMed

    Bhagwat, Anand S; Roe, Jae-Seok; Mok, Beverly Y L; Hohmann, Anja F; Shi, Junwei; Vakoc, Christopher R

    2016-04-19

    The bromodomain and extraterminal (BET) protein BRD4 can physically interact with the Mediator complex, but the relevance of this association to the therapeutic effects of BET inhibitors in cancer is unclear. Here, we show that BET inhibition causes a rapid release of Mediator from a subset of cis-regulatory elements in the genome of acute myeloid leukemia (AML) cells. These sites of Mediator eviction were highly correlated with transcriptional suppression of neighboring genes, which are enriched for targets of the transcription factor MYB and for functions related to leukemogenesis. A shRNA screen of Mediator in AML cells identified the MED12, MED13, MED23, and MED24 subunits as performing a similar regulatory function to BRD4 in this context, including a shared role in sustaining a block in myeloid maturation. These findings suggest that the interaction between BRD4 and Mediator has functional importance for gene-specific transcriptional activation and for AML maintenance. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Molecular cloning and characterization of a birch pollen minor allergen, Bet v 5, belonging to a family of isoflavone reductase-related proteins.

    PubMed

    Karamloo, F; Schmitz, N; Scheurer, S; Foetisch, K; Hoffmann, A; Haustein, D; Vieths, S

    1999-11-01

    Birch pollen is a major cause of pollinosis and is responsible for cross-reactive oral allergies to fruits, nuts, and vegetables. The major allergen, Bet v 1, has been extensively characterized, and 3 minor allergens, Bet v 2, Bet v 3, and Bet v 4, have been cloned and sequenced. Recently, another birch pollen protein with an apparent mass of 35 kd was described as a new IgE-binding protein in birch pollen with cross-reacting homologues in plant foods. The aim of this study was to determine the primary structure of the 35-kd birch pollen allergen and to investigate its immunologic properties. On the basis of a known complementary DNA fragment, a PCR strategy was applied to obtain the full-length nucleotide sequence of the coding region. The protein was expressed as His-Tag fusion protein in Escherichia coli and purified by Ni-chelate affinity chromatography. Nonfusion protein was obtained by cyanogen bromide treatment of the fusion protein. IgE-binding characteristics and potential allergenicity were investigated by immunoblot, immunoblot inhibition analysis, rat basophil leukemia-cell mediator release assay, and basophil histamine release and compared with those of natural (n) Bet v 5, recombinant (r)Bet v 1, and rBet v 2. Recombinant Bet v 5 has a mass of 33 kd, an isoelectric point of 9.0, and sequence identity of 60% to 80% to isoflavone reductase homologue proteins from various plants. On immunoblots the recombinant Bet v 5 bound IgE from 9 (32%) of 28 sera from patients allergic to birch pollen with a CAP class of at least 3; Bet v 1 was detected by 89% of these patients. IgE immunoblot and inhibition experiments showed that nBet v 5 and rBet v 5 shared identical epitopes. A rabbit antiserum raised against pea isoflavone reductase and patients' IgE reacted with Bet v 5 and proteins of similar size in several vegetable foods, including exotic fruits. A similar reaction pattern was obtained with 2 Bet v 5-specific mAbs. Furthermore, Bet v 5 triggered a dose

  13. 18 CFR 1300.102 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Gambling, betting, and... STANDARDS OF CONDUCT FOR EMPLOYEES OF TENNESSEE VALLEY AUTHORITY § 1300.102 Gambling, betting, and lotteries... TVA duty, in any gambling activity including the operation of a gambling device, in conducting a...

  14. 18 CFR 1300.102 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Gambling, betting, and... STANDARDS OF CONDUCT FOR EMPLOYEES OF TENNESSEE VALLEY AUTHORITY § 1300.102 Gambling, betting, and lotteries... TVA duty, in any gambling activity including the operation of a gambling device, in conducting a...

  15. 18 CFR 1300.102 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Gambling, betting, and... STANDARDS OF CONDUCT FOR EMPLOYEES OF TENNESSEE VALLEY AUTHORITY § 1300.102 Gambling, betting, and lotteries... TVA duty, in any gambling activity including the operation of a gambling device, in conducting a...

  16. 18 CFR 1300.102 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Gambling, betting, and... STANDARDS OF CONDUCT FOR EMPLOYEES OF TENNESSEE VALLEY AUTHORITY § 1300.102 Gambling, betting, and lotteries... TVA duty, in any gambling activity including the operation of a gambling device, in conducting a...

  17. 18 CFR 1300.102 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Gambling, betting, and... STANDARDS OF CONDUCT FOR EMPLOYEES OF TENNESSEE VALLEY AUTHORITY § 1300.102 Gambling, betting, and lotteries... TVA duty, in any gambling activity including the operation of a gambling device, in conducting a...

  18. Different T-bet expression patterns characterize particular reactive lymphoid tissue lesions.

    PubMed

    Jöhrens, K; Anagnostopoulos, I; Dürkop, H; Stein, H

    2006-03-01

    To investigate T-bet expression profiles in various lymphoid tissue diseases caused by intracellular pathogens and to compare them in disorders without an infective aetiology. Murine and in vitro experiments have shown that the expression/induction of T-bet, the master regulator of Th1 differentiation, can be achieved by obligate intracellular pathogens and high interferon (IFN)-gamma levels. Lymph node biopsies were analysed immunohistochemically employing single and double labelling for T-bet and CD20, CD4, CD8 and CD30 detection. In disorders associated with high IFN-gamma levels and intracellular pathogens (infectious mononucleosis, HIV-associated lymphadenopathy, cat-scratch disease, and toxoplasmic lymphadenitis), T-bet-expressing CD4 cells were accompanied by significant numbers of T-bet-positive CD8 and B cells. A similar profile was also found in histiocytic necrotizing (Kikuchi) lymphadenitis, a disease of unknown cause. In contrast, T-bet expression in disorders without an infective aetiology was observed in only a small portion of lymphocytes. Increased T-bet expression does not only identify intracellular infections in lymphoid tissue associated with high IFN-gamma levels, but also implies that, under these conditions, it becomes induced in B cells, which apparently support the Th1 response. T-bet expression in Kikuchi lymphadenitis underscores the hypothesis that it is caused by an intracellular microorganism.

  19. Role of bundle helices in a regulatory crosstalk in the trimeric betaine transporter BetP.

    PubMed

    Gärtner, Rebecca M; Perez, Camilo; Koshy, Caroline; Ziegler, Christine

    2011-12-02

    The Na(+)-coupled betaine symporter BetP regulates transport activity in response to hyperosmotic stress only in its trimeric state, suggesting a regulatory crosstalk between individual protomers. BetP shares the overall fold of two inverted structurally related five-transmembrane (TM) helix repeats with the sequence-unrelated Na(+)-coupled symporters LeuT, vSGLT, and Mhp1, which are neither trimeric nor regulated in transport activity. Conformational changes characteristic for this transporter fold involve the two first helices of each repeat, which form a four-TM-helix bundle. Here, we identify two ionic networks in BetP located on both sides of the membrane that might be responsible for BetP's unique regulatory behavior by restricting the conformational flexibility of the four-TM-helix bundle. The cytoplasmic ionic interaction network links both first helices of each repeat in one protomer to the osmosensing C-terminal domain of the adjacent protomer. Moreover, the periplasmic ionic interaction network conformationally locks the four-TM-helix bundle between the same neighbor protomers. By a combination of site-directed mutagenesis, cross-linking, and betaine uptake measurements, we demonstrate how conformational changes in individual bundle helices are transduced to the entire bundle by specific inter-helical interactions. We suggest that one purpose of bundle networking is to assist crosstalk between protomers during transport regulation by specifically modulating the transition from outward-facing to inward-facing state. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Effects of expertise on football betting.

    PubMed

    Khazaal, Yasser; Chatton, Anne; Billieux, Joël; Bizzini, Lucio; Monney, Grégoire; Fresard, Emmanuelle; Thorens, Gabriel; Bondolfi, Guido; El-Guebaly, Nady; Zullino, Daniele; Khan, Riaz

    2012-05-11

    Football (soccer) is one of the most popular sports in the world, including Europe. It is associated with important betting activities. A common belief, widely spread among those who participate in gambling activities, is that knowledge and expertise on football lead to better prediction skills for match outcomes. If unfounded, however, this belief should be considered as a form of "illusion of control." The aim of this study was to examine whether football experts are better than nonexperts at predicting football match scores. Two hundred and fifty-eight persons took part in the study: 21.3% as football experts, 54.3% as laypersons (non-initiated to football), and 24.4% as football amateurs. They predicted the scores of the first 10 matches of the 2008 UEFA European Football Championship. Logistic regressions were carried out to assess the link between the accuracy of the forecasted scores and the expertise of the participants (expert, amateur, layperson), controlling for age and gender. The variables assessed did not predict the accuracy of scoring prognosis (R2 ranged from 1% to 6%). Expertise, age, and gender did not appear to have an impact on the accuracy of the football match prognoses. Therefore, the belief that football expertise improves betting skills is no more than a cognitive distortion called the "illusion of control." Gamblers may benefit from psychological interventions that target the illusion of control related to their believed links between betting skills and football expertise. Public health policies may need to consider the phenomenon in order to prevent problem gambling related to football betting.

  1. Expression and Characterization of Functional Recombinant Bet v 1.0101 in the Chloroplast of Chlamydomonas reinhardtii.

    PubMed

    Hirschl, Sonja; Ralser, Claudia; Asam, Claudia; Gangitano, Alessandro; Huber, Sara; Ebner, Christof; Bohle, Barbara; Wolf, Martin; Briza, Peter; Ferreira, Fatima; Griesbeck, Christoph; Wallner, Michael

    2017-01-01

    Allergen immunotherapy (AIT) still plays a minor role in the treatment of allergic diseases. To improve the acceptance of AIT by allergic patients, the treatment has to become more convenient and efficacious. One possibility is the oral application of allergens or derivatives thereof. Therefore, we sought to produce a recombinant allergen in the green alga Chlamydomonas reinhardtii as a novel production platform. The major birch pollen allergen Bet v 1 was selected as candidate molecule, and a codon-optimized gene was synthesized and stably integrated into the microalga C. reinhardtii FUD50. Positive transformants were identified by PCR, cultured, and thereafter cells were disrupted by sonication. Bet v 1 was purified from algal total soluble protein (TSP) by affinity chromatography and characterized physicochemically as well as immunologically. All transformants showed expression of the allergen with yields between 0.01 and 0.04% of TSP. Algal-derived Bet v 1 displayed similar secondary structure elements as the Escherichia coli-produced reference allergen. Moreover, Bet v 1 produced in C. reinhardtii showed binding comparable to human IgE as well as murine Bet v 1-specific IgG. We could successfully produce recombinant Bet v 1 in C. reinhardtii. As microalgae are classified as GRAS (generally recognized as safe), the pilot study supports the development of novel allergy treatment concepts such as the oral administration of allergen-containing algal extracts for therapy. © 2017 The Author(s) Published by S. Karger AG, Basel.

  2. Sports betting marketing during sporting events: a stadium and broadcast census of Australian Football League matches.

    PubMed

    Thomas, Samantha; Lewis, Sophie; Duong, Jenny; McLeod, Colin

    2012-04-01

    Using Australian Football League (AFL) matches as a case study, we investigated the frequency, length and content of marketing strategies for sports betting during two specific settings: 1) at stadiums during four live matches; and 2) during eight televised broadcasts of matches. Census of sports betting marketing during Round 12 of the 2011 AFL premiership season. Per match, there was an average of 58.5 episodes (median 49.5, s.d 27.8) and 341.1 minutes (median 324.1 minutes and s.d 44.5) of sports betting marketing at stadiums, and 50.5 episodes (median 53.5, s.d 45.2) and 4.8 minutes (median 5.0 minutes, s.d 4.0) during televised broadcasts. A diverse range of marketing techniques were used to: a) embed sports betting within the game; b) align sports betting with fans' overall experience of the game; and c) encourage individuals to bet live during the game. There were very few visible or audible messages (such as responsible gambling or Gambler's Help messages) to counter-frame the overwhelmingly positive messages that individuals received about sports betting during the match. This study raises important questions about the impacts of saturation, integrated and impulse gambling marketing strategies in sporting matches. Future research should explore: 1) how wagering industry marketing strategies may affect the attitudes and behaviours of community sub-groups (e.g. young male sports fans, and children); and 2) which public health and policy strategies, including regulation and harm minimisation messaging, will be effective in responding to wagering industry marketing strategies during sporting matches. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

  3. STS-9 BET products

    NASA Technical Reports Server (NTRS)

    Findlay, J. T.; Kelly, G. M.; Heck, M. L.; Mcconnell, J. G.; Henry, M. W.

    1984-01-01

    The final products generated for the STS-9, which landed on December 8, 1983 are reported. The trajectory reconstruction utilized an anchor epoch of GMT corresponding to an initial altitude of h 356 kft, selected in view of the limited tracking coverage available. The final state utilized IMU2 measurements and was based on processing radar tracking from six C-bands and a single S-band station, plus six photo-theodolite cameras in the vicinity of Runway 17 at Edwards Air Force Base. The final atmosphere (FLAIR9/UN=581199C) was based on a composite of the remote measured data and the 1978 Air Force Reference Atmosphere model. The Extended BET is available as STS9BET/UN=274885C. The AEROBET and MMLE input files created are discussed. Plots of the more relevant parameters from the AEROBET (reel number NL0624) are included. Input parameters, final residual plots, a trajectory listing, and data archival information are defined.

  4. Adults Learning Mathematics: What We Should Know about Betting and Bookkeeping?

    ERIC Educational Resources Information Center

    Maasz, Juergen; Siller, Hans-Stefan

    2010-01-01

    A lot of people risk money with bets on sport events or other events. Bookkeepers that offer such bets earn a lot of money. We are making a proposal (more exactly: a concept for a part of a basic mathematics course) for learning mathematics behind the screen (internet bets are very popular). Learners should organize a "sports event"…

  5. 49 CFR 805.735-11 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Gambling, betting, and lotteries. 805.735-11... TRANSPORTATION SAFETY BOARD EMPLOYEE RESPONSIBILITIES AND CONDUCT § 805.735-11 Gambling, betting, and lotteries... the Board, in any gambling activity, including the operation of a gambling device, conducting a...

  6. 49 CFR 805.735-11 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Gambling, betting, and lotteries. 805.735-11... TRANSPORTATION SAFETY BOARD EMPLOYEE RESPONSIBILITIES AND CONDUCT § 805.735-11 Gambling, betting, and lotteries... the Board, in any gambling activity, including the operation of a gambling device, conducting a...

  7. Synthesis of silica aerogel monoliths with controlled specific surface areas and pore sizes

    NASA Astrophysics Data System (ADS)

    Gao, Bingying; Lu, Shaoxiang; Kalulu, Mulenga; Oderinde, Olayinka; Ren, Lili

    2017-07-01

    To replace traditional preparation methods of silica aerogels, a small-molecule 1,2-epoxypropane (PO) has been introduced into the preparation process instead of using ammonia as the cross-linking agent, thus generating a lightweight, high porosity, and large surface area silica aerogel monolithic. We put forward a simple solution route for the chemical synthesis of silica aerogels, which was characterized by scanning electron microscopy (SEM), TEM, XRD, FTIR, thermogravimetric analysis (TGA) and the Brunauer-Emmett-Teller (BET) method In this paper, the effect of the amount of PO on the microstructure of silica aerogels is discussed. The BET surface areas and pore sizes of the resulting silica aerogels can be freely adjusted by changing the amount of PO, which will be helpful in promoting the development of silica aerogels to fabricate other porous materials with similar requirements. We also adopted a new organic solvent sublimation drying (OSSD) method to replace traditional expensive and dangerous drying methods such as critical point drying and freeze drying. This simple approach is easy to operate and has good repeatability, which will further facilitate actual applications of silica aerogels.

  8. BET bromodomain inhibition suppresses the functional output of hematopoietic transcription factors in acute myeloid leukemia

    PubMed Central

    Roe, Jae-Seok; Mercan, Fatih; Rivera, Keith; Pappin, Darryl J.; Vakoc, Christopher R.

    2015-01-01

    Summary The bromodomain and extraterminal (BET) protein BRD4 is a validated drug target in leukemia, yet its regulatory function in this disease is not well understood. Here, we show that BRD4 chromatin occupancy in acute myeloid leukemia closely correlates with the hematopoietic transcription factors (TFs) PU.1, FLI1, ERG, C/EBPα, C/EBPβ, and MYB at nucleosome-depleted enhancer and promoter regions. We provide evidence that these TFs, in conjunction with the lysine acetyltransferase activity of p300/CBP, facilitate BRD4 recruitment to their occupied sites to promote transcriptional activation. Chemical inhibition of BET bromodomains was found to suppress the functional output each hematopoietic TF, thereby interfering with essential lineage-specific transcriptional circuits in this disease. These findings reveal a chromatin-based signaling cascade comprised of hematopoietic TFs, p300/CBP, and BRD4 that supports leukemia maintenance and is suppressed by BET bromodomain inhibition. PMID:25982114

  9. 15 CFR 0.735-17 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Gambling, betting, and lotteries. 0... RESPONSIBILITIES AND CONDUCT Regulatory Limitations Upon Employee Conduct § 0.735-17 Gambling, betting, and... for the Government, in any gambling activity including the operation of a gambling device, in...

  10. 15 CFR 0.735-17 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Gambling, betting, and lotteries. 0... RESPONSIBILITIES AND CONDUCT Regulatory Limitations Upon Employee Conduct § 0.735-17 Gambling, betting, and... for the Government, in any gambling activity including the operation of a gambling device, in...

  11. 15 CFR 0.735-17 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Gambling, betting, and lotteries. 0... RESPONSIBILITIES AND CONDUCT Regulatory Limitations Upon Employee Conduct § 0.735-17 Gambling, betting, and... for the Government, in any gambling activity including the operation of a gambling device, in...

  12. 15 CFR 0.735-17 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Gambling, betting, and lotteries. 0... RESPONSIBILITIES AND CONDUCT Regulatory Limitations Upon Employee Conduct § 0.735-17 Gambling, betting, and... for the Government, in any gambling activity including the operation of a gambling device, in...

  13. Bayesian Ensemble Trees (BET) for Clustering and Prediction in Heterogeneous Data

    PubMed Central

    Duan, Leo L.; Clancy, John P.; Szczesniak, Rhonda D.

    2016-01-01

    We propose a novel “tree-averaging” model that utilizes the ensemble of classification and regression trees (CART). Each constituent tree is estimated with a subset of similar data. We treat this grouping of subsets as Bayesian Ensemble Trees (BET) and model them as a Dirichlet process. We show that BET determines the optimal number of trees by adapting to the data heterogeneity. Compared with the other ensemble methods, BET requires much fewer trees and shows equivalent prediction accuracy using weighted averaging. Moreover, each tree in BET provides variable selection criterion and interpretation for each subset. We developed an efficient estimating procedure with improved estimation strategies in both CART and mixture models. We demonstrate these advantages of BET with simulations and illustrate the approach with a real-world data example involving regression of lung function measurements obtained from patients with cystic fibrosis. Supplemental materials are available online. PMID:27524872

  14. 19 CFR 200.735-111 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false Gambling, betting, and lotteries. 200.735-111...-111 Gambling, betting, and lotteries. An employee shall not participate, while on Government-owned or leased property or while on duty for the Government, in any gambling activity including the operation of...

  15. 19 CFR 200.735-111 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 3 2012-04-01 2012-04-01 false Gambling, betting, and lotteries. 200.735-111...-111 Gambling, betting, and lotteries. An employee shall not participate, while on Government-owned or leased property or while on duty for the Government, in any gambling activity including the operation of...

  16. 19 CFR 200.735-111 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 3 2013-04-01 2013-04-01 false Gambling, betting, and lotteries. 200.735-111...-111 Gambling, betting, and lotteries. An employee shall not participate, while on Government-owned or leased property or while on duty for the Government, in any gambling activity including the operation of...

  17. 19 CFR 200.735-111 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 3 2014-04-01 2014-04-01 false Gambling, betting, and lotteries. 200.735-111...-111 Gambling, betting, and lotteries. An employee shall not participate, while on Government-owned or leased property or while on duty for the Government, in any gambling activity including the operation of...

  18. The allergen Bet v 1 in fractions of ambient air deviates from birch pollen counts.

    PubMed

    Buters, J T M; Weichenmeier, I; Ochs, S; Pusch, G; Kreyling, W; Boere, A J F; Schober, W; Behrendt, H

    2010-07-01

    Proof is lacking that pollen count is representative for allergen exposure, also because allergens were found in nonpollen-bearing fractions of ambient air. We monitored simultaneously birch pollen and the major birch pollen allergen Bet v 1 in different size fractions of ambient air from 2004 till 2007 in Munich, Germany. Air was sampled with a ChemVol high-volume cascade impactor equipped with stages for particulate matter (PM)>10 microm, 10 microm>PM>2.5 microm, and 2.5 microm>PM>0.12 microm. Allergen was determined with a Bet v 1-specific ELISA. Pollen count was assessed with a Burkard pollen trap. We also measured the development of allergen in pollen during ripening. About 93 +/- 3% of Bet v 1 was found in the PM > 10 microm fraction, the fraction containing birch pollen. We did not measure any Bet v 1 in 2.5 microm > PM > 0.12 microm. Either in Munich no allergen was in this fraction or the allergen was absorbed to diesel soot particles that also deposit in this fraction. Pollen released 115% more Bet v 1 in 2007 than in 2004. Also within 1 year, the release of allergen from the same amount of pollen varied more than 10-fold between different days. This difference was explained by a rapidly increasing expression of Bet v 1 in pollen in the week just before pollination. Depending on the day the pollen is released during ripening, its potency varies. In general, pollen count and allergen in ambient air follow the same temporal trends. However, because a 10-fold difference can exist in allergen potency of birch pollen, symptoms might be difficult to correlate with pollen counts, but perhaps better with allergen exposure.

  19. The surface area of soil organic matter

    USGS Publications Warehouse

    Chiou, C.T.; Lee, J.-F.; Boyd, S.A.

    1990-01-01

    The previously reported surface area for soil organic matter (SOM) of 560-800 m2/g as determined by the ethylene glycol (EG) retention method was reexamined by the standard BET method based on nitrogen adsorption at liquid nitrogen temperature. Test samples consisted of two high organic content soils, a freeze-dried soil humic acid, and an oven-dried soil humic acid. The measured BET areas for these samples were less than 1 m2/g, except for the freeze-dried humic acid. The results suggest that surface adsorption of nonionic organic compounds by SOM is practically insignificant in comparison to uptake by partition. The discrepancy between the surface areas of SOM obtained by BET and EG methods was explained in terms of the 'free surface area' and the 'apparent surface area' associated with these measurements.The previously reported surface area for soil organic matter (SOM) of 560-800 m2/g as determined by the ethylene glycol (EG) retention method was reexamined by the standard BET method based on nitrogen adsorption at liquid nitrogen temperature. Test samples consisted of two high organic content soils, a freeze-dried soil humic acid, and an oven-dried soil humic acid. The measured BET areas for these samples were less than 1 m2/g, except for the freeze-dried humic acid. The results suggest that surface adsorption of nonionic organic compounds by SOM is practically insignificant in comparison to uptake by partition. The discrepancy between the surface areas of SOM obtained by BET and EG methods was explained in terms of the 'free surface area' and the 'apparent surface area' associated with these measurements.

  20. Measuring the specific surface area of natural and manmade glasses: effects of formation process, morphology, and particle size

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Papelis, Charalambos; Um, Wooyong; Russel, Charles E.

    2003-03-28

    The specific surface area of natural and manmade solid materials is a key parameter controlling important interfacial processes in natural environments and engineered systems, including dissolution reactions and sorption processes at solid-fluid interfaces. To improve our ability to quantify the release of trace elements trapped in natural glasses, the release of hazardous compounds trapped in manmade glasses, or the release of radionuclides from nuclear melt glass, we measured the specific surface area of natural and manmade glasses as a function of particle size, morphology, and composition. Volcanic ash, volcanic tuff, tektites, obsidian glass, and in situ vitrified rock were analyzed.more » Specific surface area estimates were obtained using krypton as gas adsorbent and the BET model. The range of surface areas measured exceeded three orders of magnitude. A tektite sample had the highest surface area (1.65 m2/g), while one of the samples of in situ vitrified rock had the lowest surf ace area (0.0016 m2/g). The specific surface area of the samples was a function of particle size, decreasing with increasing particle size. Different types of materials, however, showed variable dependence on particle size, and could be assigned to one of three distinct groups: (1) samples with low surface area dependence on particle size and surface areas approximately two orders of magnitude higher than the surface area of smooth spheres of equivalent size. The specific surface area of these materials was attributed mostly to internal porosity and surface roughness. (2) samples that showed a trend of decreasing surface area dependence on particle size as the particle size increased. The minimum specific surface area of these materials was between 0.1 and 0.01 m2/g and was also attributed to internal porosity and surface roughness. (3) samples whose surface area showed a monotonic decrease with increasing particle size, never reaching an ultimate surface area limit within the

  1. Synthesis and characterization of high-surface-area millimeter-sized silica beads with hierarchical multi-modal pore structure by the addition of agar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Han, Yosep; Choi, Junhyun; Tong, Meiping, E-mail: tongmeiping@iee.pku.edu.cn

    2014-04-01

    Millimeter-sized spherical silica foams (SSFs) with hierarchical multi-modal pore structure featuring high specific surface area and ordered mesoporous frameworks were successfully prepared using aqueous agar addition, foaming and drop-in-oil processes. The pore-related properties of the prepared spherical silica (SSs) and SSFs were systematically characterized by field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), small-angle X-ray diffraction (SAXRD), Hg intrusion porosimetry, and N{sub 2} adsorption–desorption isotherm measurements. Improvements in the BET surface area and total pore volume were observed at 504 m{sup 2} g{sup −1} and 5.45 cm{sup 3} g{sup −1}, respectively, after an agar addition and foaming process. Despitemore » the increase in the BET surface area, the mesopore wall thickness and the pore size of the mesopores generated from the block copolymer with agar addition were unchanged based on the SAXRD, TEM, and BJH methods. The SSFs prepared in the present study were confirmed to have improved BET surface area and micropore volume through the agar loading, and to exhibit interconnected 3-dimensional network macropore structure leading to the enhancement of total porosity and BET surface area via the foaming process. - Highlights: • Millimeter-sized spherical silica foams (SSFs) are successfully prepared. • SSFs exhibit high BET surface area and ordered hierarchical pore structure. • Agar addition improves BET surface area and micropore volume of SSFs. • Foaming process generates interconnected 3-D network macropore structure of SSFs.« less

  2. Sports betting: can gamblers beat randomness?

    PubMed

    Cantinotti, Michael; Ladouceur, Robert; Jacques, Christian

    2004-06-01

    Although skills are not considered relevant in chance-governed activities, only a few studies have assessed the extent to which sport expert skills in wagering are a manifestation of the illusion of control. This study examined (a) whether expert hockey bettors could make better predictions than chance, (b) whether expert hockey bettors could achieve greater monetary gains than chance, and (c) what kind of strategies hockey gamblers rely on when betting. Accordingly, 30 participants were asked to report their state lottery hockey bets on 6 occasions. We suggest that the information used by bettors, along with near-misses, reinforces their perception of expertise. The results of this experiment suggest that the so-called "skills" of the sports bettors are cognitive distortions. (c) 2004 APA, all rights reserved

  3. Epigenetic targeting of Hedgehog pathway transcriptional output through BET bromodomain inhibition

    PubMed Central

    Tang, Yujie; Gholamin, Sharareh; Schubert, Simone; Willardson, Minde I.; Lee, Alex; Bandopadhayay, Pratiti; Bergthold, Guillame; Masoud, Sabran; Nguyen, Brian; Vue, Nujsaubnusi; Balansay, Brianna; Yu, Furong; Oh, Sekyung; Woo, Pamelyn; Chen, Spenser; Ponnuswami, Anitha; Monje, Michelle; Atwood, Scott X.; Whitson, Ramon J.; Mitra, Siddhartha; Cheshier, Samuel H.; Qi, Jun; Beroukhim, Rameen; Tang, Jean Y.; Wechsler-Reya, Rob; Oro, Anthony E.; Link, Brian A.; Bradner, James E.; Cho, Yoon-Jae

    2014-01-01

    Hedgehog signaling drives oncogenesis in several cancers and strategies targeting this pathway have been developed, most notably through inhibition of Smoothened. However, resistance to Smoothened inhibitors occurs via genetic changes of Smoothened or other downstream Hedgehog components. Here, we overcome these resistance mechanisms by modulating GLI transcription via inhibition of BET bromodomain proteins. We show the BET bromodomain protein, BRD4, regulates GLI transcription downstream of SMO and SUFU and chromatin immunoprecipitation studies reveal BRD4 directly occupies GLI1 and GLI2 promoters, with a substantial decrease in engagement of these sites upon treatment with JQ1, a small molecule inhibitor targeting BRD4. Globally, genes associated with medulloblastoma-specific GLI1 binding sites are downregulated in response to JQ1 treatment, supporting direct regulation of GLI activity by BRD4. Notably, patient- and GEMM-derived Hedgehog-driven tumors (basal cell carcinoma, medulloblastoma and atypical teratoid/rhabdoid tumor) respond to JQ1 even when harboring genetic lesions rendering them resistant to Smoothened antagonists. PMID:24973920

  4. Learning Mathematics or Losing Money--Betting as a Topic for Mathematical Education

    ERIC Educational Resources Information Center

    Siller, Hans-Stefan; MaaB, Jurgen

    2012-01-01

    No risk, no fun--betting on sports events costs the gamblers a lot of money and brings excellent profits to those who offer the bets. Among the people who bet on a regular basis, the proportion of young adults is frighteningly high. We now suggest a concept (as part of a basic mathematics course) for acquiring the necessary mathematical knowledge…

  5. Popcorn-Derived Porous Carbon Flakes with an Ultrahigh Specific Surface Area for Superior Performance Supercapacitors.

    PubMed

    Hou, Jianhua; Jiang, Kun; Wei, Rui; Tahir, Muhammad; Wu, Xiaoge; Shen, Ming; Wang, Xiaozhi; Cao, Chuanbao

    2017-09-13

    Popcorn-derived porous carbon flakes have been successfully fabricated from the biomass of maize. Utilizing the "puffing effect", the nubby maize grain turned into materials with an interconnected honeycomb-like porous structure composed of carbon flakes. The following chemical activation method enabled the as-prepared products to possess optimized porous structures for electrochemical energy-storage devices, such as multilayer flake-like structures, ultrahigh specific surface area (S BET : 3301 m 2 g -1 ), and a high content of micropores (microporous surface area of 95%, especially the optimized sub-nanopores with the size of 0.69 nm) that can increase the specific capacitance. The as-obtained sample displayed excellent specific capacitance of 286 F g -1 at 90 A g -1 for supercapacitors. Moreover, the unique porous structure demonstrated an ideal way to improve the volumetric energy density performance. A high energy density of 103 Wh kg -1 or 53 Wh L -1 has been obtained in the case of ionic liquid electrolyte, which is the highest among reported biomass-derived carbon materials and will satisfy the urgent requirements of a primary power source for electric vehicles. This work may prove to be a fast, green, and large-scale synthesis route by using the large nubby granular materials to synthesize applicable porous carbons in energy-storage devices.

  6. A nonallergenic birch pollen allergy vaccine consisting of hepatitis PreS-fused Bet v 1 peptides focuses blocking IgG toward IgE epitopes and shifts immune responses to a tolerogenic and Th1 phenotype.

    PubMed

    Marth, Katharina; Breyer, Isabella; Focke-Tejkl, Margarete; Blatt, Katharina; Shamji, Mohamed H; Layhadi, Janice; Gieras, Anna; Swoboda, Ines; Zafred, Domen; Keller, Walter; Valent, Peter; Durham, Stephen R; Valenta, Rudolf

    2013-04-01

    Allergen-specific immunotherapy is the only allergen-specific and disease-modifying treatment for allergy. The construction and characterization of a vaccine for birch pollen allergy is reported. Two nonallergenic peptides, PA and PB, derived from the IgE-reactive areas of the major birch pollen allergen Bet v 1 were fused to the hepatitis B surface protein, PreS, in four recombinant fusion proteins containing different numbers and combinations of the peptides. Fusion proteins expressed in Escherichia coli and purified to homogeneity showed a lack of IgE reactivity and allergenic activity when tested with sera and basophils from patients allergic to birch pollen. Compared to Bet v 1 allergen, peptides PA and PB showed reduced T cell activation in PBMCs from allergic patients, whereas PreS fusion proteins induced less IL-5 and more IL-10 and IFN-γ. Immunization of rabbits with the fusion proteins, in particular with a PreS fusion protein 2PAPB-PreS, containing two copies of each peptide, induced high levels of IgG Abs against the major IgE-reactive site on Bet v 1 and related allergens. These IgG Abs inhibited allergic patients' IgE binding to Bet v 1 better than did IgG induced by immunization with complete Bet v 1. Furthermore, 2PAPB-PreS-induced IgG inhibited Bet v 1-induced basophil activation in allergic patients and CD23-facilitated allergen presentation. Our study exemplifies novel beneficial features for a PreS carrier-based peptide vaccine for birch pollen, which, in addition to the established reduction in allergenic activity, include the enhanced focusing of blocking Ab responses toward IgE epitopes, immunomodulatory activity, and reduction of CD23-facilitated allergen presentation.

  7. A Nonallergenic Birch Pollen Allergy Vaccine Consisting of Hepatitis PreS–Fused Bet v 1 Peptides Focuses Blocking IgG toward IgE Epitopes and Shifts Immune Responses to a Tolerogenic and Th1 Phenotype

    PubMed Central

    Marth, Katharina; Breyer, Isabella; Focke-Tejkl, Margarete; Blatt, Katharina; Shamji, Mohamed H.; Layhadi, Janice; Gieras, Anna; Swoboda, Ines; Zafred, Domen; Keller, Walter; Valent, Peter; Durham, Stephen R.; Valenta, Rudolf

    2014-01-01

    Allergen-specific immunotherapy is the only allergen-specific and disease-modifying treatment for allergy. The construction and characterization of a vaccine for birch pollen allergy is reported. Two nonallergenic peptides, PA and PB, derived from the IgE-reactive areas of the major birch pollen allergen Bet v 1 were fused to the hepatitis B surface protein, PreS, in four recombinant fusion proteins containing different numbers and combinations of the peptides. Fusion proteins expressed in Escherichia coli and purified to homogeneity showed a lack of IgE reactivity and allergenic activity when tested with sera and basophils from patients allergic to birch pollen. Compared to Bet v 1 allergen, peptides PA and PB showed reduced T cell activation in PBMCs from allergic patients, whereas PreS fusion proteins induced less IL-5 and more IL-10 and IFN-γ. Immunization of rabbits with the fusion proteins, in particular with a PreS fusion protein 2PAPB-PreS, containing two copies of each peptide, induced high levels of IgG Abs against the major IgE-reactive site on Bet v 1 and related allergens. These IgG Abs inhibited allergic patients’ IgE binding to Bet v 1 better than did IgG induced by immunization with complete Bet v 1. Furthermore, 2PAPB-PreS–induced IgG inhibited Bet v 1–induced basophil activation in allergic patients and CD23-facilitated allergen presentation. Our study exemplifies novel beneficial features for a PreS carrier–based peptide vaccine for birch pollen, which, in addition to the established reduction in allergenic activity, include the enhanced focusing of blocking Ab responses toward IgE epitopes, immunomodulatory activity, and reduction of CD23-facilitated allergen presentation. PMID:23440415

  8. BET inhibitors in metastatic prostate cancer: therapeutic implications and rational drug combinations.

    PubMed

    Markowski, Mark C; De Marzo, Angelo M; Antonarakis, Emmanuel S

    2017-12-01

    The bromodomain and extra-terminal (BET) family of proteins are epigenetic readers of acetylated histones regulating a vast network of protein expression across many different cancers. Therapeutic targeting of BET is an attractive area of clinical development for metastatic castration-resistant prostate cancer (mCRPC), particularly due to its putative effect on c-MYC expression and its interaction with the androgen receptor (AR). Areas covered: We speculate that a combination approach using inhibitors of BET proteins (BETi) with other targeted therapies may be required to improve the therapeutic index of BET inhibition in the management of prostate cancer. Preclinical data has identified several molecular targets that may enhance the effect of BET inhibition in the clinic. This review will summarize the known preclinical data implicating BET as an important therapeutic target in advanced prostate cancer, highlight the ongoing clinical trials targeting this protein family, and speculate on rationale combination strategies using BETi together with other agents in prostate cancer. A literature search using Pubmed was performed for this review. Expert opinion: Use of BETi in the treatment of mCRPC patients may require the addition of a second novel agent.

  9. Asthma: T-bet--a master controller?

    PubMed

    Robinson, Douglas S; Lloyd, Clare M

    2002-04-30

    The transcription factors T-bet and GATA3 are important reciprocal determinants of Th1 and Th2 T helper cell differentiation. Recent evidence suggests that these factors may affect airway immunopathology in asthma.

  10. Surface Area Analysis Using the Brunauer-Emmett-Teller (BET) Method: Standard Operating Procedure Series: SOP-C

    DTIC Science & Technology

    2016-09-01

    Method Scientific Operating Procedure Series : SOP-C En vi ro nm en ta l L ab or at or y Jonathon Brame and Chris Griggs September 2016...BET) Method Scientific Operating Procedure Series : SOP-C Jonathon Brame and Chris Griggs Environmental Laboratory U.S. Army Engineer Research and...response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing

  11. Frictional behavior and BET surface-area changes of SAFOD gouge at intermediate to seismic slip rates

    NASA Astrophysics Data System (ADS)

    Sawai, Michiyo; Shimamoto, Toshihiko; Mitchell, Thomas; Kitajima, Hiroko; Hirose, Takehiro

    2013-04-01

    The San Andreas Fault Observatory at Depth (SAFOD) Drilling site is located near the southern end of the creeping section of the San Andreas fault. Experimental studies on the frictional properties of fault gouge from SAFOD drill cores may provide valuable information on the cause of diverse fault motion. We conducted friction experiments on gouge from the southwest deformation zone (SDZ, Phase III core; Hole G-Run 2-Section 8) where creep is confirmed by ongoing borehole casing deformation, at intermediate to high slip rates (10-5 to 1.3 m/s), at a normal stress of about 1 MPa, and under both dry (room humidity) and wet (25 wt% of H2O added, drained tests) conditions. Experiments were performed with two rotary-shear friction apparatuses. One gram of gouge was placed between specimens of Belfast gabbro 25 mm in diameter surrounded by a Teflon sleeve to confine the gouge. Slip rate was first decreased and then increased in a step-wise manner to obtain the steady-state friction at intermediate slip rates. The friction coefficient increases from about 0.13 to 0.37 as the slip rate increases from 0.8 x 10-5 to 9.7 x 10-3 m/s. Our results agree with frictional strength measured at higher effective normal stress (100 MPa) by the Brown University group in the same material. Data shows pronounced velocity strengthening at intermediate slip rates, which is unfavorable for rupture nucleation and may be a reason for having creep behavior. On the other hand, the steady-state friction markedly decreases at high velocity, and such weakening may allow earthquake rupture to propagate into the creeping section, once the intermediate strength barrier is overcome. Gouge temperature, measured at the edge of the stationary sample during seismic fault motion, increased to around 175oC under dry conditions, but increased up to 100oC under wet conditions. We measured BET surface area of gouge before and after deformation to determine the energy used for grain crushing. The initial

  12. Place your bets: psychophysiological correlates of decision-making under risk.

    PubMed

    Studer, Bettina; Clark, Luke

    2011-06-01

    Emotions and their psychophysiological correlates are thought to play an important role in decision-making under risk. We used a novel gambling task to measure psychophysiological responses during selection of explicitly presented risky options and feedback processing. Active-choice trials, in which the participant had to select the size of bet, were compared to fixed-bet, no-choice trials. We further tested how the chances of winning and bet size affected choice behavior and psychophysiological arousal. Individual differences in impulsive and risk-taking traits were assessed. The behavioral results showed sensitivity to the choice requirement and to the chances of winning: Participants were faster to make a response on no-choice trials and when the chances of winning were high. In active-choice trials, electrodermal activity (EDA) increased with bet size during both selection and processing of losses. Cardiac responses were sensitive to choice uncertainty: Stronger selection-related heart rate (HR) decelerations were observed in trials with lower chances of winning, particularly on active-choice trials. Finally, betting behavior and psychophysiological responsiveness were moderately correlated with self-reported impulsivity-related traits. In conclusion, we demonstrate that psychophysiological arousal covaries with risk-sensitive decision-making outside of a learning context. Our results further highlight the differential sensitivities of EDA and HR to psychological features of the decision scenario.

  13. Birch pollen-related food allergy to legumes: identification and characterization of the Bet v 1 homologue in mungbean (Vigna radiata), Vig r 1.

    PubMed

    Mittag, D; Vieths, S; Vogel, L; Wagner-Loew, D; Starke, A; Hunziker, P; Becker, W-M; Ballmer-Weber, B K

    2005-08-01

    Recently allergic reactions to legumes mediated by Bet v 1-homologous food allergens were described for soy and peanut. In this study we assessed allergic reactions to another legume, to mungbean seedlings, and identified its Bet v 1-homologous allergen Vig r 1. Ten patients were selected who had a history of allergic reactions to mungbean seedlings and a respiratory allergy to birch pollen. The Bet v 1 homologue in mungbean seedlings, Vig r 1, was cloned by a PCR strategy, expressed in Escherichia coli, and purified by preparative SDS-PAGE. In all sera, specific IgE against birch pollen, Bet v 1, Bet v 2, Vig r 1, and the Bet v 1 homologues in soy (Gly m 4) and cherry (Pru av 1) was determined by CAP-FEIA. Cross-reactivity of specific IgE with Vig r 1, Bet v 1, Gly m 4, and Pru av 1 was assessed by immunoblot inhibition. Expression of Vig r 1 during development of mungbean seedlings and under wounding stress was analysed by immunoblotting. The Vig r 1 double band was analysed by matrix-assisted laser desorption/ionization time-of-flight and liquid chromatography/tandem mass spectrometry (LC/MS/MS). All patients were sensitized to birch pollen and Bet v 1, 20% to Bet v 2, and 90% to Gly m 4. Seventy percent of the patients showed IgE binding to a double band at 15 kDa in mungbean extract that was inhibited after pre-incubation of sera with rBet v 1. PCR cloning revealed that the mungbean homologue of Bet v 1 had a molecular weight of 16.2 kDa, a calculated pI of 4.6% and 42.8% amino acid sequence identity with Bet v 1. MS analysis confirmed similarity of the double band with the deduced Vig r 1 sequence, but also indicated the existence of other Vig r 1 isoforms. ImmunoCAP analysis detected IgE against Vig r 1 in 80% of the sera. IgE binding to Vig r 1 was inhibited with Gly m 4 in six of six and with rPru av 1 in four of six patients. Vig r 1 expression occurred during development of seedlings and was increased by wounding stress. Food allergy to mungbean

  14. Delayed bet-hedging resilience strategies under environmental fluctuations

    NASA Astrophysics Data System (ADS)

    Ogura, Masaki; Wakaiki, Masashi; Rubin, Harvey; Preciado, Victor M.

    2017-05-01

    Many biological populations, such as bacterial colonies, have developed through evolution a protection mechanism, called bet hedging, to increase their probability of survival under stressful environmental fluctuation. In this context, the concept of preadaptation refers to a common type of bet-hedging protection strategy in which a relatively small number of individuals in a population stochastically switch their phenotypes to a dormant metabolic state in which they increase their probability of survival against potential environmental shocks. Hence, if an environmental shock took place at some point in time, preadapted organisms would be better adapted to survive and proliferate once the shock is over. In many biological populations, the mechanisms of preadaptation and proliferation present delays whose influence in the fitness of the population are not well understood. In this paper, we propose a rigorous mathematical framework to analyze the role of delays in both preadaptation and proliferation mechanisms in the survival of biological populations, with an emphasis on bacterial colonies. Our theoretical framework allows us to analytically quantify the average growth rate of a bet-hedging bacterial colony with stochastically delayed reactions with arbitrary precision. We verify the accuracy of the proposed method by numerical simulations and conclude that the growth rate of a bet-hedging population shows a nontrivial dependency on their preadaptation and proliferation delays. Contrary to the current belief, our results show that faster reactions do not, in general, increase the overall fitness of a biological population.

  15. Interferon-gamma and T-bet expression in a patient with toxoplasmic lymphadenopathy.

    PubMed

    Jöhrens, Korinna; Moos, Verena; Schneider, Thomas; Stein, Harald; Anagnostopoulos, Ioannis

    2010-04-01

    Infection with Toxoplasma gondii (TG) presents in some individuals as a self-limited disease with a predominant lymphadenopathy characterized by prominent B-cell activation. As this is in contrast to the in vitro based concept of a T(h)1-immune response against TG, we investigated native lymphoid tissue and peripheral blood of a patient with serologic evidence of toxoplasmosis to verify which cells show T(h)1-response features. High-level expression of T-bet in monocytoid B-cells, in germinal center B-cells, and in a lesser amount in T cells could be demonstrated by immunohistochemistry. In vitro stimulation of lymph node cells with either TG, staphylococcus enterotoxin B, or phorbol 12-myristate 13-acetate/ionomycin revealed an interferon-gamma expression in T-bet(+) B cells only in the patient and not in controls. Similar results were found for T-bet(+) T cells which were also present in controls. CD4(+) peripheral blood cells stimulated with TG antigens showed a TG-specific but attenuated T(h)1-reactivity in the patient associated with a reduced expression of IL-2 when compared with controls. We conclude that the pathogenesis and course of toxoplasmic lymphadenopathy is based on a T(h)1-cell defect, which becomes compensated by the B cells mounting a T(h)1-like immune response.

  16. The role of ZA channel water-mediated interactions in the design of bromodomain-selective BET inhibitors.

    PubMed

    Bharatham, Nagakumar; Slavish, Peter J; Shadrick, William R; Young, Brandon M; Shelat, Anang A

    2018-05-01

    The Bromodomain and Extra-Terminal domain (BET) family of proteins are involved in the regulation of gene transcription, and their dysregulation is implicated in several diseases including cancer. BET proteins contain two tandem bromodomains (BD1 and BD2) that independently recognize acetylated-lysine residues and appear to have distinct biological roles. We compared several published co-crystal structures and found five positions near the substrate binding pocket that vary between BET bromodomains. One position located in the ZA loop has unique properties. In BRD2-4, this residue is glutamine in BD1 and lysine in BD2; in BRDT, this residue is arginine in BD1 and asparagine in BD2. Using molecular modeling, we identified differences in the water-mediated network at this position between bromodomains. Molecular dynamics simulations helped rationalize the observed bromodomain selectivity for exemplar BET inhibitors and a congeneric series of tetrahydroquinolines (THQ) that differed by a single heteroatom near the ZA channel. The 2-furan SJ830599, the most BD2-selective THQ analog, did not disrupt the water-mediated networks in either domain, but was electrostatically-repulsed by the specific arrangement of the W5 water dipole in BD1. Our work underscores the value of exploring water-mediated interactions to study ligand binding, and highlights the difficulty of optimizing polar interactions due to high desolvation penalties. Finally, we suggest further modifications to THQ-based BET inhibitors that would increase BD2-selectivity in BRD2-4, while minimizing affinity for one or both bromodomains of BRDT. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Sorption of uranium (VI) on homoionic sodium smectite experimental study and surface complexation modeling.

    PubMed

    Korichi, Smain; Bensmaili, Aicha

    2009-09-30

    )-BET specific surface area, SSA(BET) (thus, total edge site concentrations). The specific surface area should be at least 80-100m(2)/g for smectite clays in order to reach convergence during the modeling. The range of 10-20% SSA(BET) was used to estimate the values of edge site surfaces that led to the convergence during modeling. An agreement between the experimental data and model predictions is found reasonable when 15% SSA(BET) was used as edge site surface. However, the predicted U (VI) adsorption underestimated and overestimated the experimental observations at the 10 and 20% of the measured SSA(BET), respectively. The dependence of uranium sorption modeling results on specific surface area and edge site surface is useful to describe and predict U (VI) retardation as a function of chemical conditions in the field-scale reactive transport simulations. Therefore this approach can be used in the environmental quality assessment.

  18. Bromodomain and extraterminal (BET) proteins regulate biliary-driven liver regeneration.

    PubMed

    Ko, Sungjin; Choi, Tae-Young; Russell, Jacquelyn O; So, Juhoon; Monga, Satdarshan P S; Shin, Donghun

    2016-02-01

    During liver regeneration, hepatocytes are derived from pre-existing hepatocytes. However, if hepatocyte proliferation is compromised, biliary epithelial cells (BECs) become the source of new hepatocytes. We recently reported on a zebrafish liver regeneration model in which BECs extensively contribute to hepatocytes. Using this model, we performed a targeted chemical screen to identify important factors that regulate BEC-driven liver regeneration, the mechanisms of which remain largely unknown. Using Tg(fabp10a:CFP-NTR) zebrafish, we examined the effects of 44 selected compounds on BEC-driven liver regeneration. Liver size was assessed by fabp10a:DsRed expression; liver marker expression was analyzed by immunostaining, in situ hybridization and quantitative PCR. Proliferation and apoptosis were also examined. Moreover, we used a mouse liver injury model, choline-deficient, ethionine-supplemented (CDE) diet. We identified 10 compounds that affected regenerating liver size. Among them, only bromodomain and extraterminal domain (BET) inhibitors, JQ1 and iBET151, blocked both Prox1 and Hnf4a induction in BECs. BET inhibition during hepatocyte ablation blocked BEC dedifferentiation into hepatoblast-like cells (HB-LCs). Intriguingly, after JQ1 washout, liver regeneration resumed, indicating temporal, but not permanent, perturbation of liver regeneration by BET inhibition. BET inhibition after hepatocyte ablation suppressed the proliferation of newly generated hepatocytes and delayed hepatocyte maturation. Importantly, Myca overexpression, in part, rescued the proliferation defect. Furthermore, oval cell numbers in mice fed CDE diet were greatly reduced upon JQ1 administration, supporting the zebrafish findings. BET proteins regulate BEC-driven liver regeneration at multiple steps: BEC dedifferentiation, HB-LC proliferation, the proliferation of newly generated hepatocytes, and hepatocyte maturation. Copyright © 2015 European Association for the Study of the Liver

  19. Characterization of the porosity of human dental enamel and shear bond strength in vitro after variable etch times: initial findings using the BET method.

    PubMed

    Nguyen, Trang T; Miller, Arthur; Orellana, Maria F

    2011-07-01

    (1) To quantitatively characterize human enamel porosity and surface area in vitro before and after etching for variable etching times; and (2) to evaluate shear bond strength after variable etching times. Specifically, our goal was to identify the presence of any correlation between enamel porosity and shear bond strength. Pore surface area, pore volume, and pore size of enamel from extracted human teeth were analyzed by Brunauer-Emmett-Teller (BET) gas adsorption before and after etching for 15, 30, and 60 seconds with 37% phosphoric acid. Orthodontic brackets were bonded with Transbond to the samples with variable etch times and were subsequently applied to a single-plane lap shear testing system. Pore volume and surface area increased after etching for 15 and 30 seconds. At 60 seconds, this increase was less pronounced. On the contrary, pore size appears to decrease after etching. No correlation was found between variable etching times and shear strength. Samples etched for 15, 30, and 60 seconds all demonstrated clinically viable shear strength values. The BET adsorption method could be a valuable tool in enhancing our understanding of enamel characteristics. Our findings indicate that distinct quantitative changes in enamel pore architecture are evident after etching. Further testing with a larger sample size would have to be carried out for more definitive conclusions to be made.

  20. Osmosensor and osmoregulator properties of the betaine carrier BetP from Corynebacterium glutamicum in proteoliposomes.

    PubMed

    Rübenhagen, R; Rönsch, H; Jung, H; Krämer, R; Morbach, S

    2000-01-14

    The secondary glycine betaine uptake system BetP of Corynebacterium glutamicum was purified from Escherichia coli membranes in strep-tagged form after heterologous expression of the betP gene and was reconstituted in E. coli lipids. BetP retained its kinetic properties (V(max) and K(m) for betaine and Na(+)) as compared with intact cells. The influence of driving forces (Na(+) gradient and/or electrical potential) on betaine uptake was quantified in proteoliposomes. BetP was effectively regulated by the external osmolality and was stimulated by the local anesthetic tetracaine. A shift of the optimum of osmotic stimulation to higher osmolalities was linearly correlated with an increasing share of phosphatidyl glycerol, the major lipid of the C. glutamicum plasma membrane in the E. coli lipid proteoliposomes. This finding correlates with results demonstrating an identical shift when betP was expressed in E. coli instead of C. glutamicum. These data indicate that (i) BetP comprises all elements of osmosensing and osmoregulatory mechanisms of betaine uptake, (ii) osmoregulation of BetP is directly related to protein/membrane interactions, (iii) the turgor pressure presumably plays no major role in osmoregulation of BetP, and (iv) the regulatory properties of BetP may be related to the physical state of the surrounding membrane.

  1. The influence of marketing on the sports betting attitudes and consumption behaviours of young men: implications for harm reduction and prevention strategies.

    PubMed

    Deans, Emily G; Thomas, Samantha L; Derevensky, Jeffrey; Daube, Mike

    2017-01-19

    Gambling can cause significant health and social harms for individuals, their families, and communities. While many studies have explored the individual factors that may lead to and minimise harmful gambling, there is still limited knowledge about the broader range of factors that may contribute to gambling harm. There are significant regulations to prevent the marketing of some forms of gambling but comparatively limited regulations relating to the marketing of newer forms of online gambling such as sports betting. There is a need for better information about how marketing strategies may be shaping betting attitudes and behaviours and the range of policy and regulatory responses that may help to prevent the risky or harmful consumption of these products. We conducted qualitative, semi-structured interviews with 50 Australian men (aged 20-37 years) who gambled on sports. We explored their attitudes and opinions regarding sports betting marketing, the embedding of marketing within sports and other non-gambling community environments, and the implications this had for the normalisation of betting. Our findings indicate that most of the environments in which participants reported seeing or hearing betting advertisements were not in environments specifically designed for betting. Participants described that the saturation of marketing for betting products, including through sports-based commentary and sports programming, normalised betting. Participants described that the inducements offered by the industry were effective marketing strategies in getting themselves and other young men to bet on sports. Inducements were also linked with feelings of greater control over betting outcomes and stimulated some individuals to sign up with more than one betting provider. This research suggests that marketing plays a strong role in the normalisation of gambling in sports. This has the potential to increase the risks and subsequent harms associated with these products

  2. Bromodomain and Extra-terminal (BET) Protein Inhibitors Suppress Chondrocyte Differentiation and Restrain Bone Growth.

    PubMed

    Niu, Ningning; Shao, Rui; Yan, Guang; Zou, Weiguo

    2016-12-23

    Small molecule inhibitors for bromodomain and extra-terminal (BET) proteins have recently emerged as potential therapeutic agents in clinical trials for various cancers. However, to date, it is unknown whether these inhibitors have side effects on bone structures. Here, we report that inhibition of BET bromodomain proteins may suppress chondrocyte differentiation and restrain bone growth. We generated a luciferase reporter system using the chondrogenic cell line ATDC5 in which the luciferase gene was driven by the promoter of Col2a1, an elementary collagen of the chondrocyte. The Col2a1-luciferase ATDC5 system was used for rapidly screening both activators and repressors of human collagen Col2a1 gene expression, and we found that BET bromodomain inhibitors reduce the Col2a1-luciferase. Consistent with the luciferase assay, BET inhibitors decrease the expression of Col2a1 Furthermore, we constructed a zebrafish line in which the enhanced green fluorescent protein (EGFP) expression was driven by col2a1 promoter. The transgenic (col2a1-EGFP) zebrafish line demonstrated that BET inhibitors I-BET151 and (+)-JQ1 may affect EGFP expression in zebrafish. Furthermore, we found that I-BET151 and (+)-JQ1 may affect chondrocyte differentiation in vitro and inhibit zebrafish growth in vivo Mechanistic analysis revealed that BET inhibitors influenced the depletion of RNA polymerase II from the Col2a1 promoter. Collectively, these results suggest that BET bromodomain inhibition may have side effects on skeletal bone structures. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Bet-hedging applications for conservation

    USGS Publications Warehouse

    Boyce, M.S.; Kirsch, E.M.; Servheen, C.

    2002-01-01

    One of the early tenets of conservation biology is that population viability is enhanced by maintaining multiple populations of a species. The strength of this tenet is justified by principles of bet-hedging. Management strategies that reduce variance in population size will also reduce risk of extinction. Asynchrony in population fluctuations in independent populations reduces variance in the aggregate of populations whereas environmental correlation among areas increases the risk that all populations will go extinct. We review the theoretical rationale of bet-hedging and suggest applications for conservation management of least terns in Nebraska and grizzly bears in the northern Rocky Mountains of the United States. The risk of extinction for least terns will be reduced if we can sustain the small central Platte River population in addition to the larger population on the lower Platte. Similarly, by restoring grizzly bears to the Bitterroot wilderness of Idaho and Montana can reduce the probability of extinction for grizzly bears in the Rocky Mountains of the United States by as much as 69-93%.

  4. CD23 surface density on B cells is associated with IgE levels and determines IgE-facilitated allergen uptake, as well as activation of allergen-specific T cells.

    PubMed

    Selb, Regina; Eckl-Dorna, Julia; Neunkirchner, Alina; Schmetterer, Klaus; Marth, Katharina; Gamper, Jutta; Jahn-Schmid, Beatrice; Pickl, Winfried F; Valenta, Rudolf; Niederberger, Verena

    2017-01-01

    Increasing evidence suggests that the low-affinity receptor for IgE, CD23, plays an important role in controlling the activity of allergen-specific T cells through IgE-facilitated allergen presentation. We sought to determine the number of CD23 molecules on immune cells in allergic patients and to investigate whether the number of CD23 molecules on antigen-presenting cells is associated with IgE levels and influences allergen uptake and allergen-specific T-cell activation. Numbers of CD23 molecules on immune cells of allergic patients were quantified by using flow cytometry with QuantiBRITE beads and compared with total and allergen-specific IgE levels, as well as with allergen-induced immediate skin reactivity. Allergen uptake and allergen-specific T-cell activation in relation to CD23 surface density were determined by using flow cytometry in combination with confocal microscopy and T cells transfected with the T-cell receptor specific for the birch pollen allergen Bet v 1, respectively. Defined IgE-allergen immune complexes were formed with human monoclonal allergen-specific IgE and Bet v 1. In allergic patients the vast majority of CD23 molecules were expressed on naive IgD + B cells. The density of CD23 molecules on B cells but not the number of CD23 + cells correlated with total IgE levels (R S  = 0.53, P = .03) and allergen-induced skin reactions (R S  = 0.63, P = .008). Uptake of allergen-IgE complexes into B cells and activation of allergen-specific T cells depended on IgE binding to CD23 and were associated with CD23 surface density. Addition of monoclonal IgE to cultured PBMCs significantly (P = .04) increased CD23 expression on B cells. CD23 surface density on B cells of allergic patients is correlated with allergen-specific IgE levels and determines allergen uptake and subsequent activation of T cells. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  5. Design, Synthesis, and Biological Activity of 1,2,3-Triazolobenzodiazepine BET Bromodomain Inhibitors.

    PubMed

    Sharp, Phillip P; Garnier, Jean-Marc; Hatfaludi, Tamas; Xu, Zhen; Segal, David; Jarman, Kate E; Jousset, Hélène; Garnham, Alexandra; Feutrill, John T; Cuzzupe, Anthony; Hall, Peter; Taylor, Scott; Walkley, Carl R; Tyler, Dean; Dawson, Mark A; Czabotar, Peter; Wilks, Andrew F; Glaser, Stefan; Huang, David C S; Burns, Christopher J

    2017-12-14

    A number of diazepines are known to inhibit bromo- and extra-terminal domain (BET) proteins. Their BET inhibitory activity derives from the fusion of an acetyl-lysine mimetic heterocycle onto the diazepine framework. Herein we describe a straightforward, modular synthesis of novel 1,2,3-triazolobenzodiazepines and show that the 1,2,3-triazole acts as an effective acetyl-lysine mimetic heterocycle. Structure-based optimization of this series of compounds led to the development of potent BET bromodomain inhibitors with excellent activity against leukemic cells, concomitant with a reduction in c- MYC expression. These novel benzodiazepines therefore represent a promising class of therapeutic BET inhibitors.

  6. Extracting local information from crowds through betting markets

    NASA Astrophysics Data System (ADS)

    Weijs, Steven

    2015-04-01

    In this research, a set-up is considered in which users can bet against a forecasting agency to challenge their probabilistic forecasts. From an information theory standpoint, a reward structure is considered that either provides the forecasting agency with better information, paying the successful providers of information for their winning bets, or funds excellent forecasting agencies through users that think they know better. Especially for local forecasts, the approach may help to diagnose model biases and to identify local predictive information that can be incorporated in the models. The challenges and opportunities for implementing such a system in practice are also discussed.

  7. Misestimating betting behavior: the role of negative asymmetries in emotional self prediction.

    PubMed

    Andrade, Eduardo B; Claro, Danny P; Islam, Gazi

    2014-12-01

    This paper addresses the role of negative asymmetries in emotional self-prediction by looking at the extent to which individuals misestimate their own betting behavior in sequential gambles. In a series of three experimental studies, we demonstrate that losses lead to higher than planned bets whereas bets are on average carried over after gains. Such asymmetric deviations from the plan emerge (1) when monetary and non-monetary incentives are used, and (2) when participants face fair and unfair gambles. The asymmetry is based on people's inability to predict how much the negative emotions generated by a bad experience (e.g. the loss) will influence them to put more effort (e.g. bet more) than planned in an attempt to re-establish a homeostatic state in the prospect of a good experience (e.g. winning).

  8. Allergy immunotherapy with a hypoallergenic recombinant birch pollen allergen rBet v 1-FV in a randomized controlled trial.

    PubMed

    Klimek, Ludger; Bachert, Claus; Lukat, Karl-Friedrich; Pfaar, Oliver; Meyer, Hanns; Narkus, Annemie

    2015-01-01

    Pollen extracts and chemically modified allergoids are used successfully in allergen immunotherapy (AIT). Recombinant extracts offer potential advantages with respect to pharmaceutical quality, standardization and dosing. A hypoallergenic recombinant folding variant of the major birch pollen allergen (rBet v 1-FV) was compared with an established native birch preparation. A pre-seasonal, randomized, actively controlled phase II study was performed in birch pollen allergic rhino-conjunctivitis with or without asthma, GINA I/ II. 51 patients (24 rBet v 1-FV, 27 native extract) started therapy with subcutaneous allergen immunotherapy (SCIT). Primary end-point was a combined symptom medication score (SMS), changes in nasal provocation test, visual rating score and specific antibody responses secondary end-points. After one pre-seasonal treatment course the combined SMS was 5.86 (median; IQR: 14.02) for the rBet v 1-FV group versus 12.40 (median; IQR: 9.32) for the comparator during the three weeks pollen season (p = 0.330). After treatment in the second year, scores were 3.00 (median; IQR: 6.50) and 2.93 (4.86) respectively. Allergen tolerance in a nasal provocation test improved to a comparable extent in both groups. Significant increases in birch pollen-specific IgG1 and IgG4 were observed in both treatment groups following the first treatment phase and remained significantly raised until the end of the study. In this first in man, proof of concept phase II trial no statistical difference between rBet v 1-FV and an established natural pollen extract could be observed. rBet v 1-FV could be administered in higher doses than the native protein with no increase in adverse effects. The study was registered in clinicalTrials.gov (NCT00266526).

  9. Side-Bet Theory and the Three-Component Model of Organizational Commitment

    ERIC Educational Resources Information Center

    Powell, Deborah M.; Meyer, John P.

    2004-01-01

    We tested Becker's (1960) side-bet conceptualization of commitment within the context of Meyer and Allen's (1991) three-component model of organizational commitment. Employees (N=202) from various organizations completed a survey including measures of (a) seven categories of side bets (b) affective, normative, and continuance commitment, and (c)…

  10. Inhibition of BET Bromodomain Targets Genetically Diverse Glioblastoma

    PubMed Central

    Cheng, Zhixiang; Gong, Yuanying; Ma, Yufang; Lu, Kaihua; Lu, Xiang; Pierce, Larry A.; Thompson, Reid C.; Muller, Susanne; Knapp, Stefan; Wang, Jialiang

    2014-01-01

    Purpose Glioblastoma is refractory to conventional therapies. The bromodomain and extraterminal domain (BET) proteins are epigenetic readers that selectively bind to acetylated lysine residues on histone tails. These proteins recently emerged as important therapeutic targets in NUT midline carcinoma and several types of hematopoietic cancers. In this study, the therapeutic potential of a novel BET bromodomain inhibitor, JQ1, was assessed in a panel of genetically heterogeneous glioblastoma samples. Experimental Design The antineoplastic effects of JQ1 were shown using ex vivo cultures derived from primary glioblastoma xenograft lines and surgical specimens of different genetic background. The in vivo efficacy was assessed in orthotopic glioblastoma tumors. Results We showed that JQ1 induced marked G1 cell-cycle arrest and apoptosis, which was phenocopied by knockdown of individual BET family members. JQ1 treatment resulted in significant changes in expression of genes that play important roles in glioblastoma such as c-Myc, p21CIP1/WAF1, hTERT, Bcl-2, and Bcl-xL. Unlike the observations in some hematopoietic cancer cell lines, exogenous c-Myc did not significantly protect glioblastoma cells against JQ1. In contrast, ectopically expressed Bcl-xL partially rescued cells from JQ1-induced apoptosis, and knockdown of p21CIP1/WAF1 attenuated JQ1-induced cell-cycle arrest. Cells genetically engineered for Akt hyperactivation or p53/Rb inactivation did not compromise JQ1 efficacy, suggesting that these frequently mutated signaling pathways may not confer resistance to JQ1. Furthermore, JQ1 significantly repressed growth of orthotopic glioblastoma tumors. Conclusion Our results suggest potentially broad therapeutic use of BET bromodomain inhibitors for treating genetically diverse glioblastoma tumors. PMID:23403638

  11. Bistability, epigenetics, and bet-hedging in bacteria.

    PubMed

    Veening, Jan-Willem; Smits, Wiep Klaas; Kuipers, Oscar P

    2008-01-01

    Clonal populations of microbial cells often show a high degree of phenotypic variability under homogeneous conditions. Stochastic fluctuations in the cellular components that determine cellular states can cause two distinct subpopulations, a property called bistability. Phenotypic heterogeneity can be readily obtained by interlinking multiple gene regulatory pathways, effectively resulting in a genetic logic-AND gate. Although switching between states can occur within the cells' lifetime, cells can also pass their cellular state over to the next generation by a mechanism known as epigenetic inheritance and thus perpetuate the phenotypic state. Importantly, heterogeneous populations can demonstrate increased fitness compared with homogeneous populations. This suggests that microbial cells employ bet-hedging strategies to maximize survival. Here, we discuss the possible roles of interlinked bistable networks, epigenetic inheritance, and bet-hedging in bacteria.

  12. [Forms of pathological gambling: empirical research on consumers behaviour of sport betting and lottery participants].

    PubMed

    Plöntzke, Babett; Albrecht, Ulrike; Thalemann, Carolin; Grüsser, Sabine Miriam

    2004-08-01

    Gambling is one of the favourite leisure activities. 70-90 % of the grown-up population have gambled at least once in their life. Over the last few years, however, the variety of opportunities to gamble has changed. Decreasing numbers of casino visitors can be seen against an ever-increasing number of people using slot machines, and taking part in national lotteries and sport betting. Comprehensive empirical research regarding consumer behaviour and addiction potential involved in sport betting has been non-existent and only a few studies have dealt with lottery. In the present study, 108 subjects were questioned in Austrian betting offices. 33.3 % of the sample fulfilled the diagnostic criteria for pathological sport betting. Of the sport betting subjects who additionally play lottery, 22.92 % were diagnosed as being pathological lottery gamblers. Based on the criteria of substance addiction, the data demonstrate that sport betting and lottery have addiction potential and can therefore be seen as non-substance-related addiction.

  13. Harnessing BET Inhibitor Sensitivity Reveals AMIGO2 as a Melanoma Survival Gene.

    PubMed

    Fontanals-Cirera, Barbara; Hasson, Dan; Vardabasso, Chiara; Di Micco, Raffaella; Agrawal, Praveen; Chowdhury, Asif; Gantz, Madeleine; de Pablos-Aragoneses, Ana; Morgenstern, Ari; Wu, Pamela; Filipescu, Dan; Valle-Garcia, David; Darvishian, Farbod; Roe, Jae-Seok; Davies, Michael A; Vakoc, Christopher R; Hernando, Eva; Bernstein, Emily

    2017-11-16

    Bromodomain and extraterminal domain inhibitors (BETi) represent promising therapeutic agents for metastatic melanoma, yet their mechanism of action remains unclear. Here we interrogated the transcriptional effects of BETi and identified AMIGO2, a transmembrane molecule, as a BET target gene essential for melanoma cell survival. AMIGO2 is upregulated in melanoma cells and tissues compared to human melanocytes and nevi, and AMIGO2 silencing in melanoma cells induces G1/S arrest followed by apoptosis. We identified the pseudokinase PTK7 as an AMIGO2 interactor whose function is regulated by AMIGO2. Epigenomic profiling and genome editing revealed that AMIGO2 is regulated by a melanoma-specific BRD2/4-bound promoter and super-enhancer configuration. Upon BETi treatment, BETs are evicted from these regulatory elements, resulting in AMIGO2 silencing and changes in PTK7 proteolytic processing. Collectively, this study uncovers mechanisms underlying the therapeutic effects of BETi in melanoma and reveals the AMIGO2-PTK7 axis as a targetable pathway for metastatic melanoma. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Betting Decision Under Break-Streak Pattern: Evidence from Casino Gaming.

    PubMed

    Fong, Lawrence Hoc Nang; So, Amy Siu Ian; Law, Rob

    2016-03-01

    Cognitive bias is prevalent among gamblers, especially those with gambling problems. Grounded in the heuristics theories, this study contributes to the literature by examining a cognitive bias triggered by the break streak pattern in the casino setting. We postulate that gamblers tend to bet on the latest outcome when there is a break-streak pattern. Moreover, three determinants of the betting decision under break-streak pattern, including the streak length of the alternative outcome, the frequency of the latest outcome, and gender, were identified and examined in this study. A non-participatory observational study was conducted among the Cussec gamblers in a casino in Macao. An analysis of 1229 bets confirms our postulation, particularly when the streak of the alternative outcome is long, the latest outcome is frequent, and the gamblers are females. The findings provide meaningful implications for casino management and public policymakers regarding the minimization of gambling harm.

  15. BET bromodomain inhibition suppresses innate inflammatory and profibrotic transcriptional networks in heart failure

    PubMed Central

    Duan, Qiming; McMahon, Sarah; Anand, Priti; Shah, Hirsh; Thomas, Sean; Salunga, Hazel T.; Huang, Yu; Zhang, Rongli; Sahadevan, Aarathi; Lemieux, Madeleine E.; Brown, Jonathan D.; Srivastava, Deepak; Bradner, James E.; McKinsey, Timothy A.; Haldar, Saptarsi M.

    2017-01-01

    Despite current standard of care, the average 5-year mortality after an initial diagnosis of heart failure (HF) is about 40%, reflecting an urgent need for new therapeutic approaches. Previous studies demonstrated that the epigenetic reader protein bromodomain-containing protein 4 (BRD4), an emerging therapeutic target in cancer, functions as a critical coactivator of pathologic gene transactivation during cardiomyocyte hypertrophy. However, the therapeutic relevance of these findings to human disease remained unknown. We demonstrate that treatment with the BET bromodomain inhibitor JQ1 has therapeutic effects during severe, preestablished HF from prolonged pressure overload, as well as after a massive anterior myocardial infarction in mice. Furthermore, JQ1 potently blocks agonist-induced hypertrophy in human induced pluripotent stem cell–derived cardiomyocytes (iPSC-CMs). Integrated transcriptomic analyses across animal models and human iPSC-CMs reveal that BET inhibition preferentially blocks transactivation of a common pathologic gene regulatory program that is robustly enriched for NFκB and TGF-β signaling networks, typified by innate inflammatory and profibrotic myocardial genes. As predicted by these specific transcriptional mechanisms, we found that JQ1 does not suppress physiological cardiac hypertrophy in a mouse swimming model. These findings establish that pharmacologically targeting innate inflammatory and profibrotic myocardial signaling networks at the level of chromatin is effective in animal models and human cardiomyocytes, providing the critical rationale for further development of BET inhibitors and other epigenomic medicines for HF. PMID:28515341

  16. 'A place for men to come and do their thing': constructing masculinities in betting shops in London.

    PubMed

    Cassidy, Rebecca

    2014-03-01

    During fieldwork conducted with workers and customers in betting shops in London research participants consistently conceptualized betting shops as masculine spaces in contrast to the femininity of other places including home and the bingo hall. According to this argument, betting on horses and dogs was 'men's business' and betting shops were 'men's worlds'. Two explanations were offered to account for this situation. The first suggested that betting was traditionally a pastime enjoyed by men rather than women. The second was that betting is intrinsically more appealing to men because it is based on calculation and measurement, and women prefer more intuitive, simpler challenges. I use interviews with older people to describe how the legalisation of betting in cash in 1961 changed the geography of betting. I then draw upon interviews with regular customers in order to show how knowledge about betting is shared within rather than between genders. Finally, I use my experience of training and working as a cashier to describe how the particular hegemonic masculinity found in betting shops in London is maintained through myriad everyday practices which reward certain kinds of gendered performances while at the same time suppressing alternatives. The article shows how particular spaces may become gendered as an unanticipated consequence of legislation and how contingent gendered associations are both naturalized and, at the same time, subjected to intense attention. © London School of Economics and Political Science 2013.

  17. T-bet expression by Th cells promotes type 1 inflammation but is dispensable for colitis.

    PubMed

    Zimmermann, J; Kühl, A A; Weber, M; Grün, J R; Löffler, J; Haftmann, C; Riedel, R; Maschmeyer, P; Lehmann, K; Westendorf, K; Mashreghi, M-F; Löhning, M; Mack, M; Radbruch, A; Chang, H D

    2016-11-01

    The transcription factor T-bet is highly expressed by Th cells isolated from the inflamed intestine of Crohn's disease patients, and has been regarded a critical driver of murine T cell-induced colitis. However, we show here that T-bet expression by Th cells is not required for the manifestation of T-cell-induced colitis in the presence of segmented filamentous bacteria and Helicobacter hepaticus. T-bet expression by Th cells controls their survival and localization, their repertoire of chemokine and chemokine receptor expression, the accumulation of monocytes and macrophages in the inflamed colon, and their differentiation to the M1 type, i.e., type 1 inflammation. Nevertheless, T-bet-deficient Th cells efficiently induce colitis, as reflected by weight loss, diarrhea, and colon histopathology. T-bet-deficient Th cells differentiate into Th1/17 cells, able to express IFN-γ and IL-17A upon restimulation. While neutralization of IL-17A exacerbated colitis induced by wild-type or T-bet-deficient Th cells, neutralization of IFN-γ completely abolished colitis.

  18. Daring the Foolish to Take Darwin Tests: The Ethical Double Bind of Betting On Natural Hazards

    NASA Astrophysics Data System (ADS)

    Halpern, J. B.

    2017-12-01

    While couched in the framework of concentrating minds betting on natural hazards carries an ethical cost. When children dare each other to do risky things parents know that when such dares are taken harm frequently occurs. Giving those who claim that there is no hazard financial reasons to avoid ameliorative actions or to double down in support of their public stance requires a moral calculation. Challenging the conclusions of those who accept such bets while denying danger will lead them to attempt to save face by increasing risk to themselves or others. Thus such wagers, whether person to person or on betting markets, require balancing between alerting the opposing party and others to the risks of not taking action, the associated scientific consensus and the possible harmful outcomes of the bets themselves. This talk will describe strategies for minimizing potential harm while maximizing the instructive component of climate bets. Best practices include having the bet rest on a technical issue that can be authoritatively resolved in a short time. Unfortunately the nature of natural hazard risks makes it difficult to meet all of these criteria, but those making such bets should be aware of the ethical double bind

  19. Colonoscopic allergen provocation test with rBet v 1 in patients with pollen-associated food allergy.

    PubMed

    Pickert, C N; Lorentz, A; Manns, M P; Bischoff, S C

    2012-10-01

    After consumption of fruits, nuts, and vegetables, several patients with pollen allergy experience gastrointestinal (GI) tract symptoms that are possibly caused by pollen-associated food allergy. The aim of this study was to evaluate the colonoscopic allergen provocation (COLAP) test using the recombinant birch pollen allergen Bet v 1 (rBet v 1) for in vivo diagnosis of pollen-associated food allergy manifesting in the GI tract. Thirty-four patients with a history of adverse reactions to food, GI tract symptoms, and birch pollen pollinosis and five healthy controls underwent COLAP test. Twenty minutes after endoscopic challenge of the cecal mucosa with rBet v 1, the mucosal wheal and flare reaction was registered semiquantitatively, and tissue biopsy specimens were examined for eosinophil mucosal activation. The mucosal reaction to rBet v 1 was correlated with the presence of pollinosis (P = 0.004), history of adverse reaction to Bet v 1-associated food allergens (P = 0.001), and tissue eosinophils' activation (P < 0.001). A wheal and flare reaction in the COLAP test was observed in 13 of 16 patients (81%) with a history of GI tract symptoms associated with the ingestion of Bet v 1-related foods and in four of 18 (22%) patients with a negative history (P < 0.001). The control group did not develop visible mucosal reactions to rBet v 1. Systemic anaphylactic reactions did not occur. The mucosal administration of rBet v 1 by COLAP test provides a new diagnostic tool that might support the diagnosis of Bet v 1-associated food allergy manifesting in the GI tract. © 2012 John Wiley & Sons A/S.

  20. Specificity of marine microbial surface interactions.

    PubMed Central

    Imam, S H; Bard, R F; Tosteson, T R

    1984-01-01

    The macromolecular surface components involved in intraspecific cell surface interactions of the green microalga Chlorella vulgaris and closely associated bacteria were investigated. The specific surface attachment between this alga and its associated bacteria is mediated by lectin-like macromolecules associated with the surfaces of these cells. The binding activity of these surface polymers was inhibited by specific simple sugars; this suggests the involvement of specific receptor-ligand binding sites on the interactive surfaces. Epifluorescent microscopic evaluation of bacteria-alga interactions in the presence and absence of the macromolecules that mediate these interactions showed that the glycoproteins active in these processes were specific to the microbial sources from which they were obtained. The demonstration and definition of the specificity of these interactions in mixed microbial populations may play an important role in our understanding of the dynamics of marine microbial populations in the sea. PMID:6508293

  1. The Structural Features of Sports and Race Betting Inducements: Issues for Harm Minimisation and Consumer Protection.

    PubMed

    Hing, Nerilee; Sproston, Kerry; Brook, Kate; Brading, Richard

    2017-06-01

    Minimal research has been published about inducements for sports and race betting, despite their ready availability and aggressive advertising. This paper aimed to document the range and structural features of these inducements, and analyse their alignment with the harm minimisation and consumer protection goals of responsible gambling. A scan of all inducements offered on the websites of 30 major race and sports betting brands located 223 separate inducements which we categorised into 15 generic types, all offering financial incentives to purchase. These comprised sign-up offers, refer-a-friend offers, happy hours, mobile betting bonuses, multi-bet offers, refund/stake-back offers, matching stakes/deposits, winnings paid for 'close calls', bonus or better odds, bonus or better winnings, competitions, reduced commission, free bets to selected punters, cash rebates and other free bets. All inducements were subject to numerous terms and conditions which were complex, difficult to find, and obscured by legalistic language. Play-through conditions of bonus bets were particularly difficult to interpret and failed basic requirements for informed choice. Website advertisements for inducements were prominently promoted but few contained a responsible gambling message. The results were analysed to generate 12 research propositions considered worthy of empirical research to inform much needed regulatory reform in this area.

  2. Optimizing parameter choice for FSL-Brain Extraction Tool (BET) on 3D T1 images in multiple sclerosis.

    PubMed

    Popescu, V; Battaglini, M; Hoogstrate, W S; Verfaillie, S C J; Sluimer, I C; van Schijndel, R A; van Dijk, B W; Cover, K S; Knol, D L; Jenkinson, M; Barkhof, F; de Stefano, N; Vrenken, H

    2012-07-16

    Brain atrophy studies often use FSL-BET (Brain Extraction Tool) as the first step of image processing. Default BET does not always give satisfactory results on 3DT1 MR images, which negatively impacts atrophy measurements. Finding the right alternative BET settings can be a difficult and time-consuming task, which can introduce unwanted variability. To systematically analyze the performance of BET in images of MS patients by varying its parameters and options combinations, and quantitatively comparing its results to a manual gold standard. Images from 159 MS patients were selected from different MAGNIMS consortium centers, and 16 different 3DT1 acquisition protocols at 1.5 T or 3T. Before running BET, one of three pre-processing pipelines was applied: (1) no pre-processing, (2) removal of neck slices, or (3) additional N3 inhomogeneity correction. Then BET was applied, systematically varying the fractional intensity threshold (the "f" parameter) and with either one of the main BET options ("B" - bias field correction and neck cleanup, "R" - robust brain center estimation, or "S" - eye and optic nerve cleanup) or none. For comparison, intracranial cavity masks were manually created for all image volumes. FSL-FAST (FMRIB's Automated Segmentation Tool) tissue-type segmentation was run on all BET output images and on the image volumes masked with the manual intracranial cavity masks (thus creating the gold-standard tissue masks). The resulting brain tissue masks were quantitatively compared to the gold standard using Dice overlap coefficient (DOC). Normalized brain volumes (NBV) were calculated with SIENAX. NBV values obtained using for SIENAX other BET settings than default were compared to gold standard NBV with the paired t-test. The parameter/preprocessing/options combinations resulted in 20,988 BET runs. The median DOC for default BET (f=0.5, g=0) was 0.913 (range 0.321-0.977) across all 159 native scans. For all acquisition protocols, brain extraction was

  3. Betting on the outcomes of measurements: a Bayesian theory of quantum probability

    NASA Astrophysics Data System (ADS)

    Pitowsky, Itamar

    We develop a systematic approach to quantum probability as a theory of rational betting in quantum gambles. In these games of chance, the agent is betting in advance on the outcomes of several (finitely many) incompatible measurements. One of the measurements is subsequently chosen and performed and the money placed on the other measurements is returned to the agent. We show how the rules of rational betting imply all the interesting features of quantum probability, even in such finite gambles. These include the uncertainty principle and the violation of Bell's inequality among others. Quantum gambles are closely related to quantum logic and provide a new semantics for it. We conclude with a philosophical discussion on the interpretation of quantum mechanics.

  4. An extended BET format for La RC shuttle experiments: Definition and development

    NASA Technical Reports Server (NTRS)

    Findlay, J. T.; Kelly, G. M.; Henry, M. W.

    1981-01-01

    A program for shuttle post-flight data reduction is discussed. An extended Best Estimate Trajectory (BET) file was developed. The extended format results in some subtle changes to the header record. The major change is the addition of twenty-six words to each data record. These words include atmospheric related parameters, body axis rate and acceleration data, computed aerodynamic coefficients, and angular accelerations. These parameters were added to facilitate post-flight aerodynamic coefficient determinations as well as shuttle entry air data sensor analyses. Software (NEWBET) was developed to generate the extended BET file utilizing the previously defined ENTREE BET, a dynamic data file which may be either derived inertial measurement unit data or aerodynamic coefficient instrument package data, and some atmospheric information.

  5. Higher Numbers of T-Bet+ Tumor-Infiltrating Lymphocytes Associate with Better Survival in Human Epithelial Ovarian Cancer.

    PubMed

    Xu, Yun; Chen, Lujun; Xu, Bin; Xiong, Yuqi; Yang, Min; Rui, Xiaohui; Shi, Liangrong; Wu, Changping; Jiang, Jingting; Lu, Binfeng

    2017-01-01

    T-bet, a member of the T-box family of transcription factors, is a key marker of type I immune response within the tumor microenvironment, and has been previously reported by us to serve as an important prognostic indicator for human gastric cancer patients and a potential biomarker for immunotherapy. In the present study, we aimed to assess the clinical significance and prognostic value of T-bet+ tumor-infiltrating lymphocytes in human epithelial ovarian cancer. The immunohistochemistry was used to analyze the infiltration density of T-bet+ lymphoid cells in human epithelial ovarian cancer tissues, and the flow cytometry analysis was used to further analyze the presence of T-bet+ tumor-infiltrating lymphocytes subgroups in cancer tissues. Our immunohistochemistry analysis showed increased number of T-bet+ lymphoid cells in the human epithelial ovarian cancer tissues, and the flow cytometry analysis further demonstrated the presence of T-bet+ tumor-infiltrating lymphocytes subgroups including CD4+ , CD8+ T cells and NK cells. In addition, we also observed a significant association of T-bet+ tumor-infiltrating lymphocytes density in the tumor nest of cancer with not only serum CA125 levels but also with distant metastasis. However no association was observed with other characteristics like patients' age, pathological type, FIGO stage, tumor site and tumor size. Furthermore, the survival analysis showed that higher density of T-bet+ tumor-infiltrating lymphocytes both in tumor nest and tumor stroma of cancer tissues was significantly associated with better patient survival. In addition, the density of T-bet+ tumor-infiltrating lymphocytes in tumor nest appeared to be an independent risk factor for predicting patients' postoperative prognoses. Our data indicated that the key transcription factor T-bet might play an important role in the type I immune cells mediated antitumor response, and the density of T-bet+ lymphocytes in human epithelial ovarian cancer tissues

  6. Interferons direct Th2 cell reprogramming to generate a stable GATA-3(+)T-bet(+) cell subset with combined Th2 and Th1 cell functions.

    PubMed

    Hegazy, Ahmed N; Peine, Michael; Helmstetter, Caroline; Panse, Isabel; Fröhlich, Anja; Bergthaler, Andreas; Flatz, Lukas; Pinschewer, Daniel D; Radbruch, Andreas; Löhning, Max

    2010-01-29

    Current T cell differentiation models invoke separate T helper 2 (Th2) and Th1 cell lineages governed by the lineage-specifying transcription factors GATA-3 and T-bet. However, knowledge on the plasticity of Th2 cell lineage commitment is limited. Here we show that infection with Th1 cell-promoting lymphocytic choriomeningitis virus (LCMV) reprogrammed otherwise stably committed GATA-3(+) Th2 cells to adopt a GATA-3(+)T-bet(+) and interleukin-4(+)interferon-gamma(+) "Th2+1" phenotype that was maintained in vivo for months. Th2 cell reprogramming required T cell receptor stimulation, concerted type I and type II interferon and interleukin-12 signals, and T-bet. LCMV-triggered T-bet induction in adoptively transferred virus-specific Th2 cells was crucial to prevent viral persistence and fatal immunopathology. Thus, functional reprogramming of unfavorably differentiated Th2 cells may facilitate the establishment of protective immune responses. Stable coexpression of GATA-3 and T-bet provides a molecular concept for the long-term coexistence of Th2 and Th1 cell lineage characteristics in single memory T cells. Copyright 2010 Elsevier Inc. All rights reserved.

  7. STAT4 and T-bet control follicular helper T cell development in viral infections.

    PubMed

    Weinstein, Jason S; Laidlaw, Brian J; Lu, Yisi; Wang, Jessica K; Schulz, Vincent P; Li, Ningcheng; Herman, Edward I; Kaech, Susan M; Gallagher, Patrick G; Craft, Joe

    2018-01-02

    Follicular helper T (Tfh) cells promote germinal center (GC) B cell survival and proliferation and guide their differentiation and immunoglobulin isotype switching by delivering contact-dependent and soluble factors, including IL-21, IL-4, IL-9, and IFN-γ. IL-21 and IFN-γ are coexpressed by Tfh cells during viral infections, but transcriptional regulation of these cytokines is not completely understood. In this study, we show that the T helper type 1 cell (Th1 cell) transcriptional regulators T-bet and STAT4 are coexpressed with Bcl6 in Tfh cells after acute viral infection, with a temporal decline in T-bet in the waning response. T-bet is important for Tfh cell production of IFN-γ, but not IL-21, and for a robust GC reaction. STAT4, phosphorylated in Tfh cells upon infection, is required for expression of T-bet and Bcl6 and for IFN-γ and IL-21. These data indicate that T-bet is expressed with Bcl6 in Tfh cells and is required alongside STAT4 to coordinate Tfh cell IL-21 and IFN-γ production and for promotion of the GC response after acute viral challenge. © 2018 Weinstein et al.

  8. Stabilization of the dimeric birch pollen allergen Bet v 1 impacts its immunological properties.

    PubMed

    Kofler, Stefan; Ackaert, Chloé; Samonig, Martin; Asam, Claudia; Briza, Peter; Horejs-Hoeck, Jutta; Cabrele, Chiara; Ferreira, Fatima; Duschl, Albert; Huber, Christian; Brandstetter, Hans

    2014-01-03

    Many allergens share several biophysical characteristics, including the capability to undergo oligomerization. The dimerization mechanism in Bet v 1 and its allergenic properties are so far poorly understood. Here, we report crystal structures of dimeric Bet v 1, revealing a noncanonical incorporation of cysteine at position 5 instead of genetically encoded tyrosine. Cysteine polysulfide bridging stabilized different dimeric assemblies, depending on the polysulfide linker length. These dimers represent quaternary arrangements that are frequently observed in related proteins, reflecting their prevalence in unmodified Bet v 1. These conclusions were corroborated by characteristic immunologic properties of monomeric and dimeric allergen variants. Hereby, residue 5 could be identified as an allergenic hot spot in Bet v 1. The presented results refine fundamental principles in protein chemistry and emphasize the importance of protein modifications in understanding the molecular basis of allergenicity.

  9. Efficacy and safety of 4 months of sublingual immunotherapy with recombinant Mal d 1 and Bet v 1 in patients with birch pollen-related apple allergy.

    PubMed

    Kinaciyan, Tamar; Nagl, Birgit; Faustmann, Sandra; Frommlet, Florian; Kopp, Stephan; Wolkersdorfer, Martin; Wöhrl, Stefan; Bastl, Katharina; Huber, Hans; Berger, Uwe; Bohle, Barbara

    2018-03-01

    Birch pollen-related apple allergy is among the most prevalent food allergies in adolescent/adult subjects and mainly results from sensitization to the major birch pollen allergen Bet v 1 and subsequent cross-reaction with the apple protein Mal d 1. However, specific immunotherapy with birch pollen has inconsistent effects on apple allergy. We sought to compare the safety and efficacy of sublingual immunotherapy (SLIT) with 2 formulations containing either rMal d 1 or rBet v 1 on birch pollen-related apple allergy. Sixty participants with birch pollen-related apple allergy were randomized to daily sublingual application of placebo (n = 20) or 25 μg of rMal d 1 (n = 20) or rBet v 1 (n = 20) for 16 weeks. Adverse events were regularly recorded. Sublingual challenges with standardized doses of rMal d 1, skin prick tests with recombinant allergens, and measurements of allergen-specific IgE and IgG 4 antibodies were performed before and after treatment. Both formulations caused comparable, mainly local adverse events. No systemic reactions occurred. Compared with the placebo and rBet v 1-treated groups, SLIT with rMal d 1 reduced rMal d 1-induced oral symptoms (P = .001 and P = .038) accompanied by longitudinally reduced rMal d 1-specific cutaneous reactions (P = .022) and enhanced IgG 4 /IgE ratios (P = .012). SLIT with rBet v 1 neither improved the clinical reactivity to rMal d 1 nor enhanced rMal d 1-specific IgG 4 /IgE ratios. Participants receiving placebo showed no allergen-specific changes. Sublingual treatment with a recombinant food allergen was safe and clinically effective, as determined by using standardized challenges. We present a promising approach for the effective treatment of birch pollen-related apple allergy. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  10. mTORC1 promotes T-bet phosphorylation to regulate Th1 differentiation

    PubMed Central

    Chornoguz, Olesya; Hagan, Robert S.; Haile, Azeb; Arwood, Matthew L.; Gamper, Christopher J.; Banerjee, Arnob; Powell, Jonathan D.

    2017-01-01

    CD4+ T cells lacking the mTORC1 activator Rheb fail to secrete IFNγ under Th1 polarizing conditions. We hypothesized that this phenotype is due to defects in regulation of the canonical Th1 transcription factor T-bet at the level of protein phosphorylation downstream of mTORC1. To test this hypothesis, we employed targeted mass-spectrometry proteomic analysis – multiple reaction monitoring mass spectrometry (MRM-MS). We used MRM-MS to detect and quantify predicted phospho-peptides derived from T-bet. By analyzing activated murine WT and Rheb deficient CD4+ T cells, as well as murine CD4+ T cells activated in the presence of rapamycin, a pharmacologic inhibitor of mTORC1, we were able to identify 6 T-bet phosphorylation sites. Five of these are novel, and 4 sites are consistently dephosphorylated in both Rheb deficient CD4+ T-cells and T-cells treated with rapamycin, suggesting mTORC1 signaling controls their phosphorylation. Alanine mutagenesis of each of the 6 phosphorylation sites was tested for the ability to impair IFNγ expression. Single phosphorylation site mutants still support induction of IFNγ expression, however simultaneous mutation of 3 of the mTORC1-dependent sites results in significantly reduced IFNγ expression. The reduced activity of the triple mutant T-bet is associated with its failure to recruit chromatin remodeling complexes to the Ifng gene promoter. These results establish a novel mechanism by which mTORC1 regulates Th1 differentiation, through control of T-bet phosphorylation. PMID:28424242

  11. BET Acetyl-Lysine Binding Proteins Control Pathological Cardiac Hypertrophy

    PubMed Central

    Spiltoir, Jessica I.; Stratton, Matthew S.; Cavasin, Maria A.; Demos-Davies, Kim; Reid, Brian G.; Qi, Jun; Bradner, James E.; McKinsey, Timothy A.

    2014-01-01

    Cardiac hypertrophy is an independent predictor of adverse outcomes in patients with heart failure, and thus represents an attractive target for novel therapeutic intervention. JQ1, a small molecule inhibitor of bromodomain and extraterminal (BET) acetyl-lysine reader proteins, was identified in a high throughput screen designed to discover novel small molecule regulators of cardiomyocyte hypertrophy. JQ1 dose-dependently blocked agonist-dependent hypertrophy of cultured neonatal rat ventricular myocytes (NRVMs) and reversed the prototypical gene program associated with pathological cardiac hypertrophy. JQ1 also blocked left ventricular hypertrophy (LVH) and improved cardiac function in adult mice subjected to transverse aortic constriction (TAC). The BET family consists of BRD2, BRD3, BRD4 and BRDT. BRD4 protein expression was increased during cardiac hypertrophy, and hypertrophic stimuli promoted recruitment of BRD4 to the transcriptional start site (TSS) of the gene encoding atrial natriuretic factor (ANF). Binding of BRD4 to the ANF TSS was associated with increased phosphorylation of local RNA polymerase II. These findings define a novel function for BET proteins as signal-responsive regulators of cardiac hypertrophy, and suggest that small molecule inhibitors of these epigenetic reader proteins have potential as therapeutics for heart failure. PMID:23939492

  12. Release of Bet v 1 from birch pollen from 5 European countries. Results from the HIALINE study

    NASA Astrophysics Data System (ADS)

    Buters, Jeroen T. M.; Thibaudon, Michel; Smith, Matt; Kennedy, Roy; Rantio-Lehtimäki, Auli; Albertini, Roberto; Reese, Gerald; Weber, Bernhard; Galan, Carmen; Brandao, Rui; Antunes, Celia M.; Jäger, Siegfried; Berger, Uwe; Celenk, Sevcan; Grewling, Łukasz; Jackowiak, Bogdan; Sauliene, Ingrida; Weichenmeier, Ingrid; Pusch, Gudrun; Sarioglu, Hakan; Ueffing, Marius; Behrendt, Heidrun; Prank, Marje; Sofiev, Mikhail; Cecchi, Lorenzo; Hialine Working Group

    2012-08-01

    Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network). Pollen count was assessed with Hirst type pollen traps at 10 l min-1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min-1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient. Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration. Although Bet v 1 is a mixture of different

  13. Release of Bet v 1 from birch pollen from 5 European countries. Results from the HIALINE study

    NASA Astrophysics Data System (ADS)

    The HIALINE working Group; Buters, Jeroen T. M.; Thibaudon, Michel; Smith, Matt; Kennedy, Roy; Rantio-Lehtimäki, Auli; Albertini, Roberto; Reese, Gerald; Weber, Bernhard; Galan, Carmen; Brandao, Rui; Antunes, Celia M.; Jäger, Siegfried; Berger, Uwe; Celenk, Sevcan; Grewling, Łukasz; Jackowiak, Bogdan; Sauliene, Ingrida; Weichenmeier, Ingrid; Pusch, Gudrun; Sarioglu, Hakan; Ueffing, Marius; Behrendt, Heidrun; Prank, Marje; Sofiev, Mikhail; Cecchi, Lorenzo

    2012-08-01

    Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network).Pollen count was assessed with Hirst type pollen traps at 10 l min-1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min-1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient.Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration.Although Bet v 1 is a mixture of different

  14. Inhibition of BET bromodomain-dependent XIAP and FLIP expression sensitizes KRAS-mutated NSCLC to pro-apoptotic agents

    PubMed Central

    Klingbeil, Olaf; Lesche, Ralf; Gelato, Kathy A; Haendler, Bernard; Lejeune, Pascale

    2016-01-01

    Non-small cell lung cancer (NSCLC) has the highest incidence of cancer-related death worldwide and a high medical need for more effective therapies. Small-molecule inhibitors of the bromodomain and extra terminal domain (BET) family such as JQ1, I-BET762 and OTX-015 are active in a wide range of different cancer types, including lung cancer. Although their activity on oncogene expression such as c-Myc has been addressed in many studies, the effects of BET inhibition on the apoptotic pathway remain largely unknown. Here we evaluated the activity of BET bromodomain inhibitors on cell cycle distribution and on components of the apoptosis response. Using a panel of 12 KRAS-mutated NSCLC models, we found that cell lines responsive to BET inhibitors underwent apoptosis and reduced their S-phase population, concomitant with downregulation of c-Myc expression. Conversely, ectopic c-Myc overexpression rescued the anti-proliferative effect of JQ1. In the H1373 xenograft model, treatment with JQ1 significantly reduced tumor growth and downregulated the expression of c-Myc. The effects of BET inhibition on the expression of 370 genes involved in apoptosis were compared in sensitive and resistant cells and we found the expression of the two key apoptosis regulators FLIP and XIAP to be highly BET dependent. Consistent with this, combination treatment of JQ1 with the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or the pro-apoptotic chemotherapeutic agent cisplatin enhanced induction of apoptosis in both BET inhibitor sensitive and resistant cells. Further we showed that combination of JQ1 with cisplatin led to significantly improved anti-tumor efficacy in A549 tumor-bearing mice. Altogether, these results show that the identification of BET-dependent genes provides guidance for the choice of drug combinations in cancer treatment. They also demonstrate that BET inhibition primes NSCLC cells for induction of apoptosis and that a combination with pro

  15. T-bet-mediated Tim-3 expression dampens monocyte function during chronic hepatitis C virus infection.

    PubMed

    Yi, Wenjing; Zhang, Peixin; Liang, Yan; Zhou, Yun; Shen, Huanjun; Fan, Chao; Moorman, Jonathan P; Yao, Zhi Q; Jia, Zhansheng; Zhang, Ying

    2017-03-01

    Hepatitis C virus (HCV) induces a high rate of chronic infection via dysregulation of host immunity. We have previously shown that T-cell immunoglobulin and mucin domain protein-3 (Tim-3) is up-regulated on monocyte/macrophages (M/Mφ) during chronic HCV infection; little is known, however, about the transcription factor that controls its expression in these cells. In this study, we investigated the role of transcription factor, T-box expressed in T cells (T-bet), in Tim-3 expression in M/Mφ in the setting of HCV infection. We demonstrate that T-bet is constitutively expressed in resting CD14 + M/Mφ in the peripheral blood. M/Mφ from chronically HCV-infected individuals exhibit a significant increase in T-bet expression that positively correlates with an increased level of Tim-3 expression. Up-regulation of T-bet is also observed in CD14 + M/Mφ incubated with HCV + Huh7.5 cells, as well as in primary M/Mφ or monocytic THP-1 cells exposed to HCV core protein in vitro, which is reversible by blocking HCV core/gC1qR interactions. Moreover, the HCV core-induced up-regulation of T-bet and Tim-3 expression in M/Mφ can be abrogated by incubating the cells with SP600125 - an inhibitor for the c-Jun N-terminal kinase (JNK) signalling pathway. Importantly, silencing T-bet gene expression decreases Tim-3 expression and enhances interleukin-12 secretion as well as signal transducer and activator of transcription 1 phosphorylation. These data suggest that T-bet, induced by the HCV core/gC1qR interaction, enhances Tim-3 expression via the JNK pathway, leading to dampened M/Mφ function during HCV infection. These findings reveal a novel mechanism for Tim-3 regulation via T-bet during HCV infection, providing new targets to combat this global epidemic viral disease. © 2016 John Wiley & Sons Ltd.

  16. Tackling Bet v 1 and associated food allergies with a single hybrid protein.

    PubMed

    Hofer, Heidi; Asam, Claudia; Hauser, Michael; Nagl, Birgit; Laimer, Josef; Himly, Martin; Briza, Peter; Ebner, Christof; Lang, Roland; Hawranek, Thomas; Bohle, Barbara; Lackner, Peter; Ferreira, Fátima; Wallner, Michael

    2017-08-01

    Allergy vaccines should be easily applicable, safe, and efficacious. For Bet v 1-mediated birch pollen and associated food allergies, a single wild-type allergen does not provide a complete solution. We aimed to combine immunologically relevant epitopes of Bet v 1 and the 2 clinically most important related food allergens from apple and hazelnut to a single hybrid protein, termed MBC4. After identification of T cell epitope-containing parts on each of the 3 parental allergens, the hybrid molecule was designed to cover relevant epitopes and evaluated in silico. Thereby a mutation was introduced into the hybrid sequence, which should alter the secondary structure without compromising the immunogenic properties of the molecule. MBC4 and the parental allergens were purified to homogeneity. Analyses of secondary structure elements revealed substantial changes rendering the hybrid de facto nonreactive with patients' serum IgE. Nevertheless, the protein was monomeric in solution. MBC4 was able to activate T-cell lines from donors with birch pollen allergy and from mice immunized with the parental allergens. Moreover, on immunization of mice and rabbits, MBC4 induced cross-reactive IgG antibodies, which were able to block the binding of human serum IgE. Directed epitope rearrangements combined with a knowledge-based structural modification resulted in a protein unable to bind IgE from allergic patients. Still, properties to activate specific T cells or induce blocking antibodies were conserved. This suggests that MBC4 is a suitable vaccine candidate for the simultaneous treatment of Bet v 1 and associated food allergies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. The transcription factor, T-bet, primes intestine transplantation rejection and is associated with disrupted mucosal homeostasis.

    PubMed

    Ranganathan, Sarangarajan; Ashokkumar, Chethan; Ningappa, Mylarappa; Schmitt, Lori; Higgs, Brandon W; Sindhi, Rakesh

    2015-04-01

    The transcription factor, t-bet, promotes inflammatory polarization and intestinal homing of many inflammatory cells. In previous studies, the t-bet and granulysin genes were upregulated in peripheral blood before and after intestine transplantation (ITx) rejection, but not during rejection, possibly because of sequestration in allograft mucosa. Mucosal sequestration of t-bet and granulysin may also explain the presence of inflammatory CD14+ monocyte-derived macrophages (MDM) and immunoglobulin G+ B-cell lineage cells, and loss of mature non-inflammatory CD138+ plasma cells in allograft mucosa during ITx rejection in these previous studies. T-bet-stained and granulysin-stained cells, MDM and CD138+ plasma cells were evaluated with immunohistochemistry in serial biopsies from 17 children, in whom changes in MDM and CD138+ plasma cells were observed previously. T-bet-positive mucosal cells were significantly higher in postperfusion (P = 0.035) and early posttransplant biopsies (P = 0.016) among rejectors, compared with nonrejectors. T-bet-positive cell counts per high-power field (hpf) were (a) positively correlated with MDM counts/hpf in postperfusion (Spearman r = 0.73; P = 0.01) and early posttransplant biopsies (r = 0.54, r = 0.046), and (b) negatively correlated with CD138+B-/pre-plasma cells in early posttransplant biopsies (r = 0.63, P = 0.038). T-bet expression in CD14+ monocytes, CD19+B cells, and several other leukocyte subsets was higher in random blood samples from two rejectors, compared with those from five normal human subjects and three nonrejectors. Scant granulysin-stained mucosal cells precluded additional evaluation of this cytotoxin and its role in ITx rejection. The transcription factor, t-bet, primes ITx rejection, and associates with disrupted homeostatic relationships between innate and adaptive immune cells in the allograft mucosa during rejection.

  18. IFNγ Signaling Endows DCs with the Capacity to Control Type I Inflammation during Parasitic Infection through Promoting T-bet+ Regulatory T Cells

    PubMed Central

    Lee, Hyang-Mi; Fleige, Anne; Forman, Ruth; Cho, Sunglim; Khan, Aly Azeem; Lin, Ling-Li; Nguyen, Duc T.; O'Hara-Hall, Aisling; Yin, Zhinan; Hunter, Christopher A.; Muller, Werner; Lu, Li-Fan

    2015-01-01

    IFNγ signaling drives dendritic cells (DCs) to promote type I T cell (Th1) immunity. Here, we show that activation of DCs by IFNγ is equally crucial for the differentiation of a population of T-bet+ regulatory T (Treg) cells specialized to inhibit Th1 immune responses. Conditional deletion of IFNγ receptor in DCs but not in Treg cells resulted in a severe defect in this specific Treg cell subset, leading to exacerbated immune pathology during parasitic infections. Mechanistically, IFNγ-unresponsive DCs failed to produce sufficient amount of IL-27, a cytokine required for optimal T-bet induction in Treg cells. Thus, IFNγ signalling endows DCs with the ability to efficiently control a specific type of T cell immunity through promoting a corresponding Treg cell population. PMID:25658840

  19. An assay that may predict the development of IgG enhancing allergen-specific IgE binding during birch immunotherapy

    PubMed Central

    Selb, R.; Eckl-Dorna, J.; Vrtala, S.; Valenta, R.; Niederberger, V.

    2017-01-01

    Background It has been shown that birch pollen immunotherapy can induce IgG antibodies which enhance IgE binding to Bet v 1. We aimed to develop a serological assay to predict the development of antibodies which enhance IgE binding to Bet v 1 during immunotherapy. Methods In 18 patients treated by Bet v 1-fragment-specific immunotherapy, the effects of IgG antibodies specific for the fragments on the binding of IgE antibodies to Bet v 1 were measured by ELISA. Blocking and possible enhancing effects on IgE binding were compared with skin sensitivity to Bet v 1 after treatment. Results We found that fragment-specific IgG enhanced IgE binding to Bet v 1 in two patients who also showed an increase of skin sensitivity to Bet v 1. Conclusion Our results indicate that it may be possible to develop serological tests which predict the induction of unfavourable IgG antibodies enhancing the binding of IgE to Bet v 1 during immunotherapy. PMID:23998344

  20. Proteomic analysis of the major birch allergen Bet v 1 predicts allergenicity for 15 birch species.

    PubMed

    Schenk, Martijn F; Cordewener, Jan H G; America, Antoine H P; Peters, Jeroen; Smulders, Marinus J M; Gilissen, Luud J W J

    2011-08-12

    Pollen of the European and Asian white birch (Betula pendula and B. platyphylla) causes hay fever in humans. The allergenic potency of other birch species is largely unknown. To identify birch trees with a reduced allergenicity, we assessed the immunochemical characteristics of 15 species and two hybrids, representing four subgenera within the genus Betula, while focusing on the major pollen allergen Bet v 1. Antigenic and allergenic profiles of pollen extracts from these species were evaluated by SDS-PAGE and Western blot using pooled sera of birch-allergic individuals. Tryptic digests of the Bet v 1 bands were analyzed by LC-MS(E) to determine the abundance of various Bet v 1 isoforms. Bet v 1 was the most abundant pollen protein across all birch species. LC-MS(E) confirmed that pollen of all species contained a mixture of multiple Bet v 1 isoforms. Considerable differences in Bet v 1 isoform composition exist between birch species. However, isoforms that are predicted to have a high IgE-reactivity prevailed in pollen of all species. Immunoblotting confirmed that all pollen extracts were similar in immune-reactivity, implying that pollen of all birch species is likely to evoke strong allergic reactions. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Targeting AMPK-ULK1-mediated autophagy for combating BET inhibitor resistance in acute myeloid leukemia stem cells.

    PubMed

    Jang, Ji Eun; Eom, Ju-In; Jeung, Hoi-Kyung; Cheong, June-Won; Lee, Jung Yeon; Kim, Jin Seok; Min, Yoo Hong

    2017-04-03

    Bromodomain and extraterminal domain (BET) inhibitors are promising epigenetic agents for the treatment of various subsets of acute myeloid leukemia (AML). However, the resistance of leukemia stem cells (LSCs) to BET inhibitors remains a major challenge. In this study, we evaluated the mechanisms underlying LSC resistance to the BET inhibitor JQ1. We evaluated the levels of apoptosis and macroautophagy/autophagy induced by JQ1 in LSC-like leukemia cell lines and primary CD34 + CD38 - leukemic blasts obtained from AML cases with normal karyotype without recurrent mutations. JQ1 effectively induced apoptosis in a concentration-dependent manner in JQ1-sensitive AML cells. However, in JQ1-resistant AML LSCs, JQ1 induced little apoptosis and led to upregulation of BECN1/Beclin 1, increased LC3 lipidation, formation of autophagosomes, and downregulation of SQSTM1/p62. Inhibition of autophagy by pharmacological inhibitors or knockdown of BECN1 using specific siRNA enhanced JQ1-induced apoptosis in resistant cells, indicating that prosurvival autophagy occurred in these cells. Independent of MTOR signaling, activation of the AMPK (p-Thr172)-ULK1 (p-Ser555) pathway was found to be associated with JQ1-induced autophagy in resistant cells. AMPK inhibition using the pharmacological inhibitor compound C or by knockdown of PRKAA/AMPKα suppressed autophagy and promoted JQ1-induced apoptosis in AML LSCs. These findings revealed that prosurvival autophagy was one of the mechanisms involved in the resistance of AML LSCs to JQ1. Targeting the AMPK-ULK1 pathway or inhibition of autophagy could be an effective therapeutic strategy for combating resistance to BET inhibitors in AML and other types of cancer.

  2. The major birch allergen, Bet v 1, shows affinity for a broad spectrum of physiological ligands.

    PubMed

    Mogensen, Jesper E; Wimmer, Reinhard; Larsen, Jørgen N; Spangfort, Michael D; Otzen, Daniel E

    2002-06-28

    Bet v 1 is a 17-kDa protein abundantly present in the pollen of the White birch tree and is the primary cause of birch pollen allergy in humans. Its three-dimensional structure is remarkable in that a solvent-accessible cavity traverses the core of the molecule. The biological function of Bet v 1 is unknown, although it is homologous to a family of pathogenesis-related proteins in plants. In this study we first show that Bet v 1 in the native state is able to bind the fluorescent probe 8-anilino-1-naphthalenesulfonic acid (ANS). ANS binds to Bet v 1 with 1:1 stoichiometry, and NMR data indicate that binding takes place in the cavity. Using an ANS displacement assay, we then identify a range of physiologically relevant ligands, including fatty acids, flavonoids, and cytokinins, which generally bind with low micromolar affinity. The ability of these ligands to displace ANS suggests that they also bind in the cavity, although the exact binding sites seem to vary among different ligands. The cytokinins, for example, seem to bind at a separate site close to ANS, because they increase the fluorescence of the ANS. Bet v 1 complex. Also, the fluorescent sterol dehydroergosterol binds to Bet v 1 as demonstrated by direct titrations. This study provides the first qualitative and quantitative data on the ligand binding properties of this important pollen allergen. Our findings indicate that ligand binding is important for the biological function of Bet v 1.

  3. Analysis of the role of betL in contributing to the growth and survival of Listeria monocytogenes LO28.

    PubMed

    Sleator, R D; Gahan CGM; O'Driscoll, B; Hill, C

    2000-09-25

    Survival of the food-borne pathogen Listeria monocytogenes in environments of elevated osmolarity and reduced temperature is attributed, at least in part, to the accumulation of the trimethylammonium compound glycine betaine. Previously we identified betL, a gene encoding the secondary glycine betaine transporter BetL, which we linked to the salt tolerance of Listeria. In this report, we demonstrate that betL, preceded by a consensus sigmaB-dependent promoter, is regulated by osmotic up-shock, at least in part at the level of transcription. Using allelic exchange mutagenesis we constructed an in-frame deletion in betL, and used this mutant to determine the role of BetL in contributing to the growth and survival of L. monocytogenes, both in a high risk food (Camembert cheese) and animal model. Our results indicate that while BetL plays an important role in glycine betaine mediated osmoprotection, mutating the gene does not significantly effect either the cryotolerance or virulence of the organism.

  4. High correlation of specific IgE sensitization between birch pollen, soy and apple allergens indicates pollen-food allergy syndrome among birch pollen allergic patients in northern China.

    PubMed

    Hao, Guo-Dong; Zheng, Yi-Wu; Wang, Zhi-Xiang; Kong, Xing-Ai; Song, Zhi-Jing; Lai, Xu-Xin; Spangfort, Michael D

    2016-05-01

    Birch pollen sensitization and associated pollen-food syndrome among Chinese allergic patients have not been investigated. Sera from 203 allergic patients from the northern part of China and collected during February to July 2014 were investigated. Specific immunoglobulin E (IgE) against birch pollen extract Bet v and major birch pollen allergen Bet v 1 were measured using the ADVIA Centaur. The presence of major apple allergen Mal d 1 and soy bean allergen Gly m 4 specific IgE was measured by ImmunoCAP 100. Among the 203 sera, 34 sera (16.7%) had specific IgE to Bet v and of these, 28 sera (82.4%) contained Bet v 1-specific IgE. Among the 28 sera with Bet v 1-specific IgE, 27 sera (96.4%) contained Mal d 1-specific IgE and 22 sera (78.6%) contained Gly m 4-specific IgE. Of the 34 Bet v-positive sera, 6 sera (17.6%) contained no specific IgE for Bet v 1, Mal d 1, or Gly m 4. Almost all Bet v-positive sera were donated during the birch pollen season. The prevalence of birch allergy among patients visiting health care during pollen season can be as high as 16.7% in Tangshan City. The majority of Chinese birch allergic patients are IgE-sensitized to the major birch pollen allergen Bet v 1 as well as to the major apple allergen Mal d 1 and soy bean allergen Gly m 4. A relatively high number of patients (17.6%) are IgE-sensitized to birch pollen allergen(s) other than Bet v 1. The high prevalence of specific IgE to Mal d 1 and Gly m 4 among Bet v 1-sensitized patients indicates that pollen-food allergy syndrome could be of clinical relevance in China.

  5. Leishmania-infected MHC class IIhigh dendritic cells polarize CD4+ T cells toward a nonprotective T-bet+ IFN-γ+ IL-10+ phenotype.

    PubMed

    Resende, Mariana; Moreira, Diana; Augusto, Jorge; Cunha, Joana; Neves, Bruno; Cruz, Maria Teresa; Estaquier, Jérôme; Cordeiro-da-Silva, Anabela; Silvestre, Ricardo

    2013-07-01

    A differential behavior among infected and bystander dendritic cells (DCs) has been explored in different infection models. We have analyzed both populations sorted on contact with visceral Leishmania infantum on a susceptible mice model evaluating the subsequent repercussions on adaptive immune response. Our results demonstrate a clear dichotomy between the immunomodulatory abilities of bystander and infected DCs. The bystander population presents increased levels of IL-12p40 and costimulatory molecules being capable to induce CD4(+) T cell activation with immune protective capabilities. In contrast, infected DCs, which express lower costimulatory molecules and higher levels of IL-10, promote the development of Leishmania Ag-specific, nonprotective T-bet(+)IFN-γ(+)IL-10(+) CD4(+) T cells with an effector phenotype. This specific polarization was found to be dependent on IL-12p70. Splenic infected DCs recovered from chronic infected animals are similarly capable to polarize ex vivo syngeneic naive CD4(+) T cells toward a T-bet(+)IFN-γ(+)IL-10(+) phenotype. Further analysis revealed that only MHC class II(high)-infected DCs were responsible for this polarization. The adoptive transfer of such polarized CD4(+) T cells facilitates visceral leishmaniasis in BALB/c mice in a clear contrast with their counterpart generated with bystander DCs that significantly potentiate protection. Further, we demonstrated that CD4(+) T cells primed by infected DCs in an IL-10 free system, thus deprived of T-bet(+)IFN-γ(+)IL-10(+) population, restore the immune response and reduce parasite load, supporting a deleterious role of IFN-γ(+)IL-10(+) T cells in the maintenance of infection. Overall, our results highlight novel subversion mechanisms by which nonprotective T-bet(+)IFN-γ(+)IL-10(+) T cells are associated with chronicity and prolonged parasite persistence.

  6. Effect of Cytomegalovirus (CMV) and Ageing on T-Bet and Eomes Expression on T-Cell Subsets.

    PubMed

    Hassouneh, Fakhri; Lopez-Sejas, Nelson; Campos, Carmen; Sanchez-Correa, Beatriz; Tarazona, Raquel; Pera, Alejandra; Solana, Rafael

    2017-06-29

    The differential impact of ageing and cytomegalovirus (CMV) latent infection on human T-cell subsets remains to some extent controversial. The purpose of this study was to analyse the expression of the transcription factors T-bet and Eomes and CD57 on CD4+, CD4 hi CD8 lo and CD8+ T-cell subsets in healthy individuals, stratified by age and CMV serostatus. The percentage of CD4+ T-cells expressing T-bet or Eomes was very low, in particular in CD4+ T-cells from young CMV-seronegative individuals, and were higher in CMV-seropositive older individuals, in both CD57- and CD57+ CD4+ T-cells. The study of the minor peripheral blood double-positive CD4 hi CD8 lo T-cells showed that the percentage of these T-cells expressing both Eomes and T-bet was higher compared to CD4+ T-cells. The percentage of CD4 hi CD8 lo T-cells expressing T-bet was also associated with CMV seropositivity and the coexpression of Eomes, T-bet and CD57 on CD4 hi CD8 lo T-cells was only observed in CMV-seropositive donors, supporting the hypothesis that these cells are mature effector memory cells. The percentage of T-cells expressing Eomes and T-bet was higher in CD8+ T-cells than in CD4+ T-cells. The percentages of CD8+ T-cells expressing Eomes and T-bet increased with age in CMV-seronegative and -seropositive individuals and the percentages of CD57- CD8+ and CD57+ CD8+ T-cells coexpressing both transcription factors were similar in the different groups studied. These results support that CMV chronic infection and/or ageing are associated to the expansion of highly differentiated CD4+, CD4 hi CD8 lo and CD8+ T-cells that differentially express T-bet and Eomes suggesting that the expression of these transcription factors is essential for the generation and development of an effector-memory and effector T lymphocytes involved in conferring protection against chronic CMV infection.

  7. Final STS-35 Columbia descent BET products and results for LaRC OEX investigations

    NASA Technical Reports Server (NTRS)

    Oakes, Kevin F.; Findlay, John T.; Jasinski, Rachel A.; Wood, James S.

    1991-01-01

    Final STS-35 'Columbia' descent Best Estimate Trajectory (BET) products have been developed for Langley Research Center (LaRC) Orbiter Experiments (OEX) investigations. Included are the reconstructed inertial trajectory profile; the Extended BET, which combines the inertial data and, in this instance, the National Weather Service atmospheric information obtained via Johnson Space Center; and the Aerodynamic BET. The inertial BET utilized Inertial Measurement Unit 1 (IMU1) dynamic measurements for deterministic propagation during the ENTREE estimation process. The final estimate was based on the considerable ground based C-band tracking coverage available as well as Tracking Data and Relay Satellite System (TDRSS) Doppler data, a unique use of the latter for endo-atmospheric flight determinations. The actual estimate required simultaneous solutions for the spacecraft position and velocity, spacecraft attitude, and six IMU parameters - three gyro biases and three accelerometer scale factor correction terms. The anchor epoch for this analysis was 19,200 Greenwich Mean Time (GMT) seconds which corresponds to an initial Shuttle altitude of approximately 513 kft. The atmospheric data incorporated were evaluated based on Shuttle derived considerations as well as comparisons with other models. The AEROBET was developed based on the Extended BET, the measured spacecraft configuration information, final mass properties, and the final Orbiter preoperation databook. The latter was updated based on aerodynamic consensus incrementals derived by the latest published FAD. The rectified predictions were compared versus the flight computed values and the resultant differences were correlated versus ensemble results for twenty-two previous STS entry flights.

  8. Bet hedging via seed banking in desert evening primroses (Oenothera, Onagraceae): demographic evidence from natural populations.

    PubMed

    Evans, Margaret E K; Ferrière, Régis; Kane, Michael J; Venable, D Lawrence

    2007-02-01

    Bet hedging is one solution to the problem of an unpredictably variable environment: fitness in the average environment is sacrificed in favor of lower variation in fitness if this leads to higher long-run stochastic mean fitness. While bet hedging is an important concept in evolutionary ecology, empirical evidence that it occurs is scant. Here we evaluate whether bet hedging occurs via seed banking in natural populations of two species of desert evening primroses (Oenothera, Onagraceae), one annual and one perennial. Four years of data on plants and 3 years of data on seeds yielded two transitions for the entire life cycle. One year was exceptionally dry, leading to reproductive failure in the sample areas, and the other was above average in precipitation, leading to reproductive success in four of five populations. Stochastic simulations of population growth revealed patterns indicative of bet hedging via seed banking, particularly in the annual populations: variance in fitness and fitness in the average environment were lower with seed banking than without, whereas long-run stochastic mean fitness was higher with seed banking than without across a wide range of probabilities of the wet year. This represents a novel, unusually rigorous demonstration of bet hedging from field data.

  9. Suppression of interferon β gene transcription by inhibitors of bromodomain and extra-terminal (BET) family members.

    PubMed

    Malik, Nazma; Vollmer, Stefan; Nanda, Sambit Kumar; Lopez-Pelaez, Marta; Prescott, Alan; Gray, Nathanael; Cohen, Philip

    2015-06-15

    PLK (Polo-like kinase) inhibitors, such as BI-2536, have been reported to suppress IFNB (encoding IFNβ, interferon β) gene transcription induced by ligands that activate TLR3 (Toll-like receptor 3) and TLR4. In the present study, we found that BI-2536 is likely to exert this effect by preventing the interaction of the transcription factors IRF3 (interferon-regulatory factor 3) and c-Jun with the IFNB promoter, but without affecting the TBK1 {TANK [TRAF (tumour-necrosis-factor-receptor-associated factor)-associated nuclear factor κB activator]-binding kinase 1}-catalysed phosphorylation of IRF3 at Ser³⁹⁶, the dimerization and nuclear translocation of IRF3 or the phosphorylation of c-Jun and ATF2 (activating transcription factor 2). Although BI-2536 inhibits few other kinases tested, it interacts with BET (bromodomain and extra-terminal) family members and displaces them from acetylated lysine residues on histones. We found that BET inhibitors that do not inhibit PLKs phenocopied the effect of BI-2536 on IFNB gene transcription. Similarly, BET inhibitors blocked the interaction of IRF5 with the IFNB promoter and the secretion of IFNβ induced by TLR7 or TLR9 ligands in the human plasmacytoid dendritic cell line GEN2.2, but without affecting the nuclear translocation of IRF5. We found that the BET family member BRD4 (bromodomain-containing protein 4) was associated with the IFNB promoter and that this interaction was enhanced by TLR3- or TLR4-ligation and prevented by BI-2536 and other BET inhibitors. Our results establish that BET family members are essential for TLR-stimulated IFNB gene transcription by permitting transcription factors to interact with the IFNB promoter. They also show that the interaction of the IFNB promoter with BRD4 is regulated by TLR ligation and that BI-2536 is likely to suppress IFNB gene transcription by targeting BET family members. © 2015 The Author(s).

  10. Surface modification and electrochemical properties of activated carbons for supercapacitor electrodes

    NASA Astrophysics Data System (ADS)

    Yang, Dan; Qiu, Wenmei; Xu, Jingcai; Han, Yanbing; Jin, Hongxiao; Jin, Dingfeng; Peng, Xiaoling; Hong, Bo; Li, Ji; Ge, Hongliang; Wang, Xinqing

    2015-12-01

    Modifications with different acids (HNO3, H2SO4, HCl and HF, respectively) were introduced to treat the activated carbons (ACs) surface. The microstructures and surface chemical properties were discussed by X-ray diffraction (XRD), thermogravimetric analysis (TGA), ASAP, Raman spectra and Fourier transform infrared (FTIR) spectra. The ACs electrode-based supercapacitors were assembled with 6 mol ṡ L-1 KOH electrolyte. The electrochemical properties were studied by galvanostatic charge-discharge and cyclic voltammetry. The results indicated that although the BET surface area of modified ACs decreased, the functional groups were introduced and the ash contents were reduced on the surface of ACs, receiving larger specific capacitance to initial AC. The specific capacitance of ACs modified with HCl, H2SO4, HF and HNO3 increased by 31.4%, 23%, 21% and 11.6%, respectively.

  11. 22 CFR 1203.735-210 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Gambling, betting, and lotteries. 1203.735-210... RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Employees § 1203.735-210 Gambling... while on duty for the Government, in any gambling activity including the operation of a gambling device...

  12. 15 CFR 0.735-17 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Gambling, betting, and lotteries. 0.735-17 Section 0.735-17 Commerce and Foreign Trade Office of the Secretary of Commerce EMPLOYEE... organizational support or for benefit or welfare funds for their own members) and similar agency-approved...

  13. 22 CFR 1203.735-210 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Gambling, betting, and lotteries. 1203.735-210... RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Employees § 1203.735-210 Gambling... while on duty for the Government, in any gambling activity including the operation of a gambling device...

  14. 22 CFR 1203.735-210 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Gambling, betting, and lotteries. 1203.735-210... RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Employees § 1203.735-210 Gambling... while on duty for the Government, in any gambling activity including the operation of a gambling device...

  15. 22 CFR 1203.735-210 - Gambling, betting, and lotteries.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Gambling, betting, and lotteries. 1203.735-210... RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Employees § 1203.735-210 Gambling... while on duty for the Government, in any gambling activity including the operation of a gambling device...

  16. Magnetocaloric Effect in Layered Organic Conductor λ-(BETS)2FeCl4

    NASA Astrophysics Data System (ADS)

    Sugiura, Shiori; Shimada, Kazuo; Tajima, Naoya; Nishio, Yutaka; Terashima, Taichi; Isono, Takayuki; Kato, Reizo; Zhou, Biao; Uji, Shinya

    2018-04-01

    Magnetocaloric effect (MCE) and magnetic torque measurements have been carried out in the π-d system λ-(BETS)2FeCl4 [BETS = bis(ethylenedithio)tetraselenafulvalene], which shows an antiferromagnetic insulating (AFI) phase below ˜8.5 K. In the magnetic torque curve, a sharp structure at ˜1.2 T and a step at ˜10 T are observed at low temperatures, which are caused by the spin-flop (SF) transition and the transition from the AFI to paramagnetic metallic (PM) phase, respectively. The MCE, directly related to the magnetic entropy, shows a small sharp peak at the SF transition and a sharp dip at the AFI-PM transition. The overall feature above 3 K is qualitatively interpreted by a simple picture: antiferromagnetic (AF) π spins and paramagnetic 3d spins at the Fe sites. However, a broad dip in the MCE is additionally found at ˜5 T below ˜3 K, which is not explained by the above picture. The results are compared with those of κ-(BETS)2FeBr4, which shows an AF order of the 3d spins at the Fe sites.

  17. c-Abl-Mediated Tyrosine Phosphorylation of the T-bet DNA-Binding Domain Regulates CD4+ T-Cell Differentiation and Allergic Lung Inflammation ▿

    PubMed Central

    Chen, An; Lee, Sang-Myeong; Gao, Beixue; Shannon, Stephen; Zhu, Zhou; Fang, Deyu

    2011-01-01

    The tyrosine kinase c-Abl is required for full activation of T cells, while its role in T-cell differentiation has not been characterized. We report that c-Abl deficiency skews CD4+ T cells to type 2 helper T cell (Th2) differentiation, and c-Abl−/− mice are more susceptible to allergic lung inflammation. c-Abl interacts with and phosphorylates T-bet, a Th1 lineage transcription factor. c-Abl-mediated phosphorylation enhances the transcriptional activation of T-bet. Interestingly, three tyrosine residues within the T-bet DNA-binding domain are the predominant sites of phosphorylation by c-Abl. Mutation of these tyrosine residues inhibits the promoter DNA-binding activity of T-bet. c-Abl regulates Th cell differentiation in a T-bet-dependent manner because genetic deletion of T-bet in CD4+ T cells abolishes c-Abl-deficiency-mediated enhancement of Th2 differentiation. Reintroduction of T-bet-null CD4+ T cells with wild-type T-bet, but not its tyrosine mutant, rescues gamma interferon (IFN-γ) production and inhibits Th2 cytokine production. Therefore, c-Abl catalyzes tyrosine phosphorylation of the DNA-binding domain of T-bet to regulate CD4+ T cell differentiation. PMID:21690296

  18. BET Bromodomain Inhibitors Enhance Efficacy and Disrupt Resistance to AR Antagonists in the Treatment of Prostate Cancer.

    PubMed

    Asangani, Irfan A; Wilder-Romans, Kari; Dommeti, Vijaya L; Krishnamurthy, Pranathi M; Apel, Ingrid J; Escara-Wilke, June; Plymate, Stephen R; Navone, Nora M; Wang, Shaomeng; Feng, Felix Y; Chinnaiyan, Arul M

    2016-04-01

    Next-generation antiandrogen therapies, such as enzalutamide and abiraterone, have had a profound impact on the management of metastatic castration-resistant prostate cancer (mCRPC). However, mCRPC patients invariably develop resistance to these agents. Here, a series of clonal cell lines were developed from enzalutamide-resistant prostate tumor xenografts to study the molecular mechanism of resistance and test their oncogenic potential under various treatment conditions. Androgen receptor (AR) signaling was maintained in these cell lines, which acquired potential resistance mechanisms, including expression of AR-variant 7 (AR-v7) and glucocorticoid receptor. BET bromodomain inhibitors were shown previously to attenuate AR signaling in mCRPC; here, we demonstrate the efficacy of bromodomain and extraterminal (BET) inhibitors in enzalutamide-resistant prostate cancer models. AR antagonists, enzalutamide, and ARN509 exhibit enhanced prostate tumor growth inhibition when combined with BET inhibitors, JQ1 and OTX015, respectively. Taken together, these data provide a compelling preclinical rationale to combine BET inhibitors with AR antagonists to subvert resistance mechanisms. Therapeutic combinations of BET inhibitors and AR antagonists may enhance the clinical efficacy in the treatment of mCRPC. http://mcr.aacrjournals.org/content/molcanres/14/4/324/F1.large.jpg ©2016 American Association for Cancer Research.

  19. Role of T-bet, the master regulator of Th1 cells, in the cytotoxicity of murine CD4+ T cells.

    PubMed

    Eshima, Koji; Misawa, Kana; Ohashi, Chihiro; Iwabuchi, Kazuya

    2018-05-01

    Although CD4 + T cells are generally regarded as helper T cells, some activated CD4 + T cells have cytotoxic properties. Given that CD4 + cytotoxic T lymphocytes (CTLs) often secrete IFN-γ, CTL activity among CD4 + T cells may be attributable to Th1 cells, where a T-box family molecule, T-bet serves as the "master regulator". However, although the essential contribution of T-bet to expression of IFN-γ has been well-documented, it remains unclear whether T-bet is involved in CD4 + T cell-mediated cytotoxicity. In this study, to investigate the ability of T-bet to confer cytolytic activity on CD4 + T cells, the T-bet gene (Tbx21) was introduced into non-cytocidal CD4 + T cell lines and their cytolytic function analyzed. Up-regulation of FasL (CD178), which provided the transfectant with cytotoxicity, was observed in Tbx21transfected CD4 + T cells but not in untransfected parental cells. In one cell line, T-bet transduction also induced perforin gene (Prf1) expression and Tbx21 transfectants efficiently killed Fas - target cells. Although T-bet was found to repress up-regulation of CD40L (CD154), which controls FasL-mediated cytolysis, the extent of CD40L up-regulation on in vitro-differentiated Th1 cells was similar to that on Th2 cells, suggesting the existence of a compensatory mechanism. These results collectively indicate that T-bet may be involved in the expression of genes, such as FasL and Prf1, which confer cytotoxicity on Th1 cells. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

  20. Nonselective inhibition of the epigenetic transcriptional regulator BET induces marked lymphoid and hematopoietic toxicity in mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Dong U., E-mail: lee.dong@gene.com

    Bromo and extra terminal (BET) proteins (BRD2, BRD3, BRD4 and BRDT) are epigenetic transcriptional regulators required for efficient expression of growth promoting, cell cycle progression and antiapoptotic genes. Through their bromodomain, these proteins bind to acetylated lysine residues of histones and are recruited to transcriptionally active chromatin. Inhibition of the BET-histone interaction provides a tractable therapeutic strategy to treat diseases that may have epigenetic dysregulation. JQ1 is a small molecule that blocks BET interaction with histones. It has been shown to decrease proliferation of patient-derived multiple myeloma in vitro and to decrease tumor burden in vivo in xenograft mouse models.more » While targeting BET appears to be a viable and efficacious approach, the nonclinical safety profile of BET inhibition remains to be well-defined. We report that mice dosed with JQ1 at efficacious exposures demonstrate dose-dependent decreases in their lymphoid and immune cell compartments. At higher doses, JQ1 was not tolerated and due to induction of significant body weight loss led to early euthanasia. Flow cytometry analysis of lymphoid tissues showed a decrease in both B- and T-lymphocytes with a concomitant decrease in peripheral white blood cells that was confirmed by hematology. Further investigation with the inactive enantiomer of JQ1 showed that these in vivo effects were on-target mediated and not elicited through secondary pharmacology due to chemical structure.« less

  1. THE EVOLUTION OF BET-HEDGING ADAPTATIONS TO RARE SCENARIOS

    PubMed Central

    King, Oliver D.

    2007-01-01

    When faced with a variable environment, organisms may switch between different strategies according to some probabilistic rule. In an infinite population, evolution is expected to favor the rule that maximizes geometric mean fitness. If some environments are encountered only rarely, selection may not be strong enough for optimal switching probabilities to evolve. Here we calculate the evolution of switching probabilities in a finite population by analyzing fixation probabilities of alleles specifying switching rules. We calculate the conditions required for the evolution of phenotypic switching as a form of bet-hedging as a function of the population size N, the rateθ at which a rare environment is encountered, and the selective advantage s associated with switching in the rare environment. We consider a simplified model in which environmental switching and phenotypic switching are one-way processes, and mutation is symmetric and rare with respect to the timescale of fixation events. In this case, the approximate requirements for bet-hedging to be favored by a ratio of at least R are that sN > log(R) and θN>R. PMID:17915273

  2. DietBet: A Web-Based Program that Uses Social Gaming and Financial Incentives to Promote Weight Loss

    PubMed Central

    Rosen, Jamie

    2014-01-01

    Background Web-based commercial weight loss programs are increasing in popularity. Despite their significant public health potential, there is limited research on the effectiveness of such programs. Objective The objective of our study was to examine weight losses produced by DietBet and explore whether baseline and engagement variables predict weight outcomes. Methods DietBet is a social gaming website that uses financial incentives and social influence to promote weight loss. Players bet money and join a game. All players have 4 weeks to lose 4% of their initial body weight. At enrollment, players can choose to share their participation on Facebook. During the game, players interact with one another and report their weight loss on the DietBet platform. At week 4, all players within each game who lose at least 4% of initial body weight are declared winners and split the pool of money bet at the start of the game. Official weigh-in procedures are used to verify weights at the start of the game and at the end. Results From December 2012 to July 2013, 39,387 players (84.04% female, 33,101/39,387; mean weight 87.8kg, SD 22.6kg) competed in 1934 games. The average amount bet was US $27 (SD US $22). A total of 65.63% (25,849/39,387) provided a verified weight at the end of the 4-week competition. The average intention-to-treat weight loss was 2.6% (SD 2.3%). Winners (n=17,171) won an average of US $59 (SD US $35) and lost 4.9% (SD 1.0%) of initial body weight, with 30.68% (5268/17,171) losing 5% or more of their initial weight. Betting more money at game entry, sharing on Facebook, completing more weigh-ins, and having more social interactions during the game predicted greater weight loss and greater likelihood of winning (Ps<.001). In addition, weight loss clustered within games (P<.001), suggesting that players influenced each others’ weight outcomes. Conclusions DietBet, a social gaming website, reached nearly 40,000 individuals in just 7 months and produced

  3. Nickel Nanoparticles cause exaggerated lung and airway remodeling in mice lacking the T-box transcription factor, TBX21 (T-bet)

    PubMed Central

    2014-01-01

    Background Nickel nanoparticles (NiNPs) are increasingly used in a variety of industrial applications, including the manufacturing of multi-walled carbon nanotubes (MWCNTs). While occupational nickel exposure is a known cause of pulmonary alveolitis, fibrosis, and cancer, the health risks of NiNPs are not well understood, especially in susceptible individuals such as asthmatics. The T-box transcription factor Tbx21 (T-bet) maintains Th1 cell development and loss of T-bet is associated with a shift towards Th2 type allergic airway inflammation that characterizes asthma. The purpose of this study was to determine the role of T-bet in susceptibility to lung remodeling by NiNPs or MWCNTs. Methods Wild-type (WT) and T-bet-/- mice were exposed to NiNPs or MWCNTs (4 mg/kg) by oropharyngeal aspiration (OPA). Necropsy was performed at 1 and 21 days. Bronchoalveolar lavage fluid (BALF) was collected for differential counting of inflammatory cells and for measurement of cytokines by ELISA. The left lung was collected for histopathology. The right lung was analyzed for cytokine or mucin (MUC5AC and MUC5B) mRNAs. Results Morphometry of alcian-blue/periodic acid Schiff (AB/PAS)-stained lung tissue showed that NiNPs significantly increased mucous cell metaplasia in T-bet-/- mice at 21 days (p < 0.001) compared to WT mice, and increased MUC5AC and MUC5B mRNAs (p < 0.05). MWCNTs also increased mucous cell metaplasia in T-bet-/- mice, but to a lesser extent than NiNPs. Chronic alveolitis was also increased by NiNPs, but not MWCNTs, in T-bet-/- mice compared to WT mice at 21 days (P < 0.001). NiNPs also increased IL-13 and eosinophils (p < 0.001) in BALF from T-bet-/- mice after 1 day. Interestingly, the chemokine CCL2 in the BALF of T-bet-/- mice was increased at 1 and 21 days (p < 0.001 and p < 0.05, respectively) by NiNPs, and to a lesser extent by MWCNTs at 1 day. Treatment of T-bet-/- mice with a monoclonal anti-CCL2 antibody enhanced Ni

  4. Surface-specific additive manufacturing test artefacts

    NASA Astrophysics Data System (ADS)

    Townsend, Andrew; Racasan, Radu; Blunt, Liam

    2018-06-01

    Many test artefact designs have been proposed for use with additive manufacturing (AM) systems. These test artefacts have primarily been designed for the evaluation of AM form and dimensional performance. A series of surface-specific measurement test artefacts designed for use in the verification of AM manufacturing processes are proposed here. Surface-specific test artefacts can be made more compact because they do not require the large dimensions needed for accurate dimensional and form measurements. The series of three test artefacts are designed to provide comprehensive information pertaining to the manufactured surface. Measurement possibilities include deviation analysis, surface texture parameter data generation, sub-surface analysis, layer step analysis and build resolution comparison. The test artefacts are designed to provide easy access for measurement using conventional surface measurement techniques, for example, focus variation microscopy, stylus profilometry, confocal microscopy and scanning electron microscopy. Additionally, the test artefacts may be simply visually inspected as a comparative tool, giving a fast indication of process variation between builds. The three test artefacts are small enough to be included in every build and include built-in manufacturing traceability information, making them a convenient physical record of the build.

  5. Influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for the synthesis of dimethyl carbonate

    NASA Astrophysics Data System (ADS)

    Zhang, Guoqiang; Li, Zhong; Zheng, Huayan; Hao, Zhiqiang; Wang, Xia; Wang, Jiajun

    2016-12-01

    Activated carbon (AC) supported Cu catalysts are employed to study the influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for oxidative carbonylation of methanol to dimethyl carbonate (DMC). The AC supports are thermal treated under different temperatures in order to adjust the levels of surface oxygenated groups. The AC supports are characterized by BET, TPD-MS and XRD, and the Cu/AC catalysts are characterized by BET, XRD, TEM, XPS, AAS, CH3OH-TPD and N2O chemisorption. The results show that as the treatment temperature is below 800 °C, the BET surface area of the corresponding AC supports are nearly unchanged and close to that of the original AC (1529.6 m2/g). But as the thermal treatment temperature is elevated from 1000 to 1600 °C, the BET surface area of AC supports gradually decreases from 1407.6 to 972.2 m2/g. After loading of Cu, the BET surface area of copper catalysts is in the range of 834.4 to 1545.3 m2/g, which is slightly less than that of the respective supports. When AC is thermal treated at 400 and 600 °C, the unstable carboxylic acid and anhydrides groups are selectively removed, which has weakened the mobility and agglomeration of Cu species during the calcination process, and thus improve the Cu species dispersion over AC support. But as the treatment temperature is elevated from 600 °C to 1200 °C, the Cu species dispersion begins to decline suggesting further removal of stable surface oxygenated groups is unfavorable for Cu species dispersion. Moreover, higher thermal treatment temperature (above 1200 °C) promotes the graphitization degree of AC and leds to the decrease of Cu loading on AC support. Meanwhile, the removal of surface oxygenated groups by thermal treatment is conducive to the formation of more π-sites, and thus promote the reduction of Cu2+ to Cu+ and Cu0 as active centers. The specific surface area of (Cu+ + Cu0) is improved by thermal treatment of AC

  6. Chemical weathering rates of a soil chronosequence on granitic alluvium: I. Quantification of mineralogical and surface area changes and calculation of primary silicate reaction rates

    USGS Publications Warehouse

    White, A.F.; Blum, A.E.; Schulz, M.S.; Bullen, T.D.; Harden, J.W.; Peterson, M.L.

    1996-01-01

    Mineral weathering rates are determined for a series of soils ranging in age from 0.2-3000 Ky developed on alluvial terraces near Merced in the Central Valley of California. Mineralogical and elemental abundances exhibit time-dependent trends documenting the chemical evolution of granitic sand to residual kaolinite and quartz. Mineral losses with time occur in the order: hornblende > plagioclase > K-feldspar. Maximum volume decreases of >50% occur in the older soils. BET surface areas of the bulk soils increase with age, as do specific surface areas of aluminosilicate mineral fractions such as plagioclase, which increases from 0.4-1.5 m2 g-1 over 600 Ky. Quartz surface areas are lower and change less with time (0.11-0.23 m2 g-1). BET surface areas correspond to increasing external surface roughness (?? = 10-600) and relatively constant internal surface area (??? 1.3 m2 g-1). SEM observations confirm both surface pitting and development of internal porosity. A numerical model describes aluminosilicate dissolution rates as a function of changes in residual mineral abundance, grain size distributions, and mineral surface areas with time. A simple geometric treatment, assuming spherical grains and no surface roughness, predicts average dissolution rates (plagioclase, 10-17.4; K-feldspar, 10-17.8; and hornblende, 10-17.5 mol cm-1 s-1) that are constant with time and comparable to previous estimates of soil weathering. Average rates, based on BET surface area measurements and variable surface roughnesses, are much slower (plagioclase, 10-19.9; K-feldspar, 10-20.5; and hornblende 10-20.1 mol cm-2 s-1). Rates for individual soil horizons decrease by a factor of 101.5 over 3000 Ky indicating that the surface reactivities of minerals decrease as the physical surface areas increase. Rate constants based on BET estimates for the Merced soils are factors of 103-104 slower than reported experimental dissolution rates determined from freshly prepared silicates with low surface

  7. Post-flight BET products for the 2nd discovery entry, STS-19 (51-A)

    NASA Technical Reports Server (NTRS)

    Kelly, G. M.; Mcconnell, J. G.; Heck, M. L.; Troutman, P. A.; Waters, L. A.; Findlay, J. T.

    1985-01-01

    The post-flight products for the second Discovery flight, STS-19 (51-A), are summarized. The inertial best estimate trajectory (BET), BT19D19/UN=169750N, was developed using spacecraft dynamic measurements from Inertial Measurement Unit 2 (IMU2) in conjunction with the best tracking coverage available for any of the earlier Shuttle entries. As a consequence of the latter, an anchor epoch was selected which conforms to an initial altitude of greater than a million feet. The Extended BET, ST19BET/UN=274885C, incorporated the previously mentioned inertial reconstructed state information and the Langley Atmospheric Information Retrieval System (LAIRS) atmosphere, ST19MET/UN=712662N, with some minor exceptions. Primary and back-up AEROBET reels are NK0165 and NK0201, respectively. This product was only developed over the lowermost 360 kft altitude range due to atmosphere problems but this relates to altitudes well above meaningful signal in the IMUs. Summary results generated from the AEROBET for this flight are presented with meaningful configuration and statistical comparisons from the previous thirteen flights. Modified maximum likelihood estimation (MMLE) files were generated based on IMU2 and the Rate Gyro Assembly/Accelerometer Assembly (RGA/AA), respectively. Appendices attached define spacecraft and physical constants utilized, show plots of the final tracking data residuals from the post-flight fit, list relevant parameters from the BET at a two second spacing, and retain for archival purpose all relevant input and output tapes and files generated.

  8. Surface cleanliness of fluid systems, specification for

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This specification establishes surface cleanliness levels, test methods, cleaning and packaging requirements, and protection and inspection procedures for determining surface cleanliness. These surfaces pertain to aerospace parts, components, assemblies, subsystems, and systems in contact with any fluid medium.

  9. Stromal remodeling by the BET bromodomain inhibitor JQ1 suppresses the progression of human pancreatic cancer.

    PubMed

    Yamamoto, Keisuke; Tateishi, Keisuke; Kudo, Yotaro; Hoshikawa, Mayumi; Tanaka, Mariko; Nakatsuka, Takuma; Fujiwara, Hiroaki; Miyabayashi, Koji; Takahashi, Ryota; Tanaka, Yasuo; Ijichi, Hideaki; Nakai, Yousuke; Isayama, Hiroyuki; Morishita, Yasuyuki; Aoki, Taku; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro; Fukayama, Masashi; Koike, Kazuhiko

    2016-09-20

    Inhibitors of bromodomain and extraterminal domain (BET) proteins, a family of chromatin reader proteins, have therapeutic efficacy against various malignancies. However, the detailed mechanisms underlying the anti-tumor effects in distinct tumor types remain elusive. Here, we show a novel antitumor mechanism of BET inhibition in pancreatic ductal adenocarcinoma (PDAC). We found that JQ1, a BET inhibitor, decreased desmoplastic stroma, a hallmark of PDAC, and suppressed the growth of patient-derived tumor xenografts (PDX) of PDACs. In vivo antitumor effects of JQ1 were not always associated with the JQ1 sensitivity of respective PDAC cells, and were rather dependent on the suppression of tumor-promoting activity in cancer-associated fibroblasts (CAFs). JQ1 inhibited Hedgehog and TGF-β pathways as potent regulators of CAF activation and suppressed the expression of α-SMA, extracellular matrix, cytokines, and growth factors in human primary CAFs. Consistently, conditioned media (CM) from CAFs promoted the proliferation of PDAC cells along with the activation of ERK, AKT, and STAT3 pathways, though these effects were suppressed when CM from JQ1-treated CAFs was used. Mechanistically, chromatin immunoprecipitation experiments revealed that JQ1 reduced TGF-β-dependent gene expression by disrupting the recruitment of the transcriptional machinery containing BET proteins. Finally, combination therapy with gemcitabine plus JQ1 showed greater efficacy than gemcitabine monotherapy against PDAC in vivo. Thus, our results reveal BET proteins as the critical regulators of CAF-activation and also provide evidence that stromal remodeling by epigenetic modulators can be a novel therapeutic option for PDAC.

  10. Evaluation of Advanced Reactive Surface Area Estimates for Improved Prediction of Mineral Reaction Rates in Porous Media

    NASA Astrophysics Data System (ADS)

    Beckingham, L. E.; Mitnick, E. H.; Zhang, S.; Voltolini, M.; Yang, L.; Steefel, C. I.; Swift, A.; Cole, D. R.; Sheets, J.; Kneafsey, T. J.; Landrot, G.; Anovitz, L. M.; Mito, S.; Xue, Z.; Ajo Franklin, J. B.; DePaolo, D.

    2015-12-01

    CO2 sequestration in deep sedimentary formations is a promising means of reducing atmospheric CO2 emissions but the rate and extent of mineral trapping remains difficult to predict. Reactive transport models provide predictions of mineral trapping based on laboratory mineral reaction rates, which have been shown to have large discrepancies with field rates. This, in part, may be due to poor quantification of mineral reactive surface area in natural porous media. Common estimates of mineral reactive surface area are ad hoc and typically based on grain size, adjusted several orders of magnitude to account for surface roughness and reactivity. This results in orders of magnitude discrepancies in estimated surface areas that directly translate into orders of magnitude discrepancies in model predictions. Additionally, natural systems can be highly heterogeneous and contain abundant nano- and micro-porosity, which can limit connected porosity and access to mineral surfaces. In this study, mineral-specific accessible surface areas are computed for a sample from the reservoir formation at the Nagaoka pilot CO2 injection site (Japan). Accessible mineral surface areas are determined from a multi-scale image analysis including X-ray microCT, SEM QEMSCAN, XRD, SANS, and SEM-FIB. Powder and flow-through column laboratory experiments are performed and the evolution of solutes in the aqueous phase is tracked. Continuum-scale reactive transport models are used to evaluate the impact of reactive surface area on predictions of experimental reaction rates. Evaluated reactive surface areas include geometric and specific surface areas (eg. BET) in addition to their reactive-site weighted counterparts. The most accurate predictions of observed powder mineral dissolution rates were obtained through use of grain-size specific surface areas computed from a BET-based correlation. Effectively, this surface area reflects the grain-fluid contact area, or accessible surface area, in the powder

  11. Performance modeling of a wearable brain PET (BET) camera

    NASA Astrophysics Data System (ADS)

    Schmidtlein, C. R.; Turner, J. N.; Thompson, M. O.; Mandal, K. C.; Häggström, I.; Zhang, J.; Humm, J. L.; Feiglin, D. H.; Krol, A.

    2016-03-01

    Purpose: To explore, by means of analytical and Monte Carlo modeling, performance of a novel lightweight and low-cost wearable helmet-shaped Brain PET (BET) camera based on thin-film digital Geiger Avalanche Photo Diode (dGAPD) with LSO and LaBr3 scintillators for imaging in vivo human brain processes for freely moving and acting subjects responding to various stimuli in any environment. Methods: We performed analytical and Monte Carlo modeling PET performance of a spherical cap BET device and cylindrical brain PET (CYL) device, both with 25 cm diameter and the same total mass of LSO scintillator. Total mass of LSO in both the BET and CYL systems is about 32 kg for a 25 mm thick scintillator, and 13 kg for 10 mm thick scintillator (assuming an LSO density of 7.3 g/ml). We also investigated a similar system using an LaBr3 scintillator corresponding to 22 kg and 9 kg for the 25 mm and 10 mm thick systems (assuming an LaBr3 density of 5.08 g/ml). In addition, we considered a clinical whole body (WB) LSO PET/CT scanner with 82 cm ring diameter and 15.8 cm axial length to represent a reference system. BET consisted of distributed Autonomous Detector Arrays (ADAs) integrated into Intelligent Autonomous Detector Blocks (IADBs). The ADA comprised of an array of small LYSO scintillator volumes (voxels with base a×a: 1.0 <= a <= 2.0 mm and length c: 3.0 <= c <= 6.0 mm) with 5-65 μm thick reflective layers on its five sides and sixth side optically coupled to the matching array of dGAPDs and processing electronics with total thickness of 50 μm. Simulated energy resolution was 10.8% and 3.3% for LSO and LaBr3 respectively and the coincidence window was set at 2 ns. The brain was simulated as a sphere of uniform F-18 activity with diameter of 10 cm embedded in a center of water sphere with diameter of 10 cm. Results: Analytical and Monte Carlo models showed similar results for lower energy window values (458 keV versus 445 keV for LSO, and 492 keV versus 485 keV for LaBr3

  12. Influence of membrane composition on osmosensing by the betaine carrier BetP from Corynebacterium glutamicum.

    PubMed

    Schiller, Dirk; Ott, Vera; Krämer, Reinhard; Morbach, Susanne

    2006-03-24

    The glycine betaine carrier BetP from Corynebacterium glutamicum was recently shown to function as both an osmosensor and osmoregulator in proteoliposomes made from Escherichia coli phospholipids by sensing changes in the internal K+ concentration as a measure of hyperosmotic stress (Rübenhagen, R., Morbach, S., and Krämer, R. (2001) EMBO J. 20, 5412-5420). Furthermore, evidence was provided that a stretch of 25 amino acids of the C-terminal domain of BetP is critically involved in K+ sensing. This K+-sensitive region has been further characterized. Glu572 turned out to be important for osmosensing in E. coli cells and in proteoliposomes made from E. coli phospholipids. BetP mutants E572K, E572P, and E572A/H573A/R574A were unable to detect an increase in the internal K+ concentration in this membrane environment. However, these BetP variants regained their ability to detect osmotic stress in membranes with increased phosphatidylglycerol content, i.e. in intact C. glutamicum cells or in proteoliposomes mimicking the composition of the C. glutamicum membrane. Mutants E572P and Y550P were still insensitive to osmotic stress also in this membrane background. These results led to the following conclusions. (i) The K+ sensor in mutants E572Q, E572D, and E572K is only partially impaired. (ii) Restoration of activity regulation is not possible if the correct conformation or orientation of the C-terminal domain is compromised by a proline residue at position 572 or 550. (iii) Phosphatidylglycerol in the membrane of C. glutamicum seems to stabilize the inactive conformation of BetP C252T and other mutants.

  13. Engineering description of the ascent/descent bet product

    NASA Technical Reports Server (NTRS)

    Seacord, A. W., II

    1986-01-01

    The Ascent/Descent output product is produced in the OPIP routine from three files which constitute its input. One of these, OPIP.IN, contains mission specific parameters. Meteorological data, such as atmospheric wind velocities, temperatures, and density, are obtained from the second file, the Corrected Meteorological Data File (METDATA). The third file is the TRJATTDATA file which contains the time-tagged state vectors that combine trajectory information from the Best Estimate of Trajectory (BET) filter, LBRET5, and Best Estimate of Attitude (BEA) derived from IMU telemetry. Each term in the two output data files (BETDATA and the Navigation Block, or NAVBLK) are defined. The description of the BETDATA file includes an outline of the algorithm used to calculate each term. To facilitate describing the algorithms, a nomenclature is defined. The description of the nomenclature includes a definition of the coordinate systems used. The NAVBLK file contains navigation input parameters. Each term in NAVBLK is defined and its source is listed. The production of NAVBLK requires only two computational algorithms. These two algorithms, which compute the terms DELTA and RSUBO, are described. Finally, the distribution of data in the NAVBLK records is listed.

  14. Limitations of the widely used GAM42a and BET42a probes targeting bacteria in the Gammaproteobacteria radiation.

    PubMed

    Yeates, Christine; Saunders, Aaron M; Crocetti, Gregory R; Blackall, Linda L

    2003-05-01

    The 23S rRNA-targeted probes GAM42a and BET42a provided equivocal results with the uncultured gammaproteobacterium 'Candidatus Competibacter phosphatis' where some cells bound GAM42a and other cells bound BET42a in fluorescence in situ hybridization (FISH) experiments. Probes GAM42a and BET42a span positions 1027-1043 in the 23S rRNA and differ from each other by one nucleotide at position 1033. Clone libraries were prepared from PCR products spanning the 16S rRNA genes, intergenic spacer region and 23S rRNA genes from two mixed cultures enriched in 'Candidatus C. phosphatis'. With individual clone inserts, the 16S rDNA portion was used to confirm the source organism as 'Candidatus C. phosphatis' and the 23S rDNA portion was used to determine the sequence of the GAM42a/BET42a probe target region. Of the 19 clones sequenced, 8 had the GAM42a probe target (T at position 1033) and 11 had G at position 1033, the only mismatch with GAM42a. However, none of the clones had the BET42a probe target (A at 1033). Non-canonical base-pairing between the 23S rRNA of 'Candidatus C. phosphatis' with G at position 1033 and GAM42a (G-A) or BET42a (G-T) is likely to explain the probing anomalies. A probe (GAM42_C1033) was optimized for use in FISH, targeting cells with G at position 1033, and was found to highlight not only some 'Candidatus C. phosphatis' cells, but also other bacteria. This demonstrates that there are bacteria in addition to 'Candidatus C. phosphatis' with the GAM42_C1033 probe target and not the BET42a or GAM42a probe target.

  15. Serratia entomophila bet gene induction and the impact of glycine betaine accumulation on desiccation tolerance.

    PubMed

    Sheen, T R; O'Callaghan, M; Smalley, D J; Ronson, C W; Hurst, M R H

    2013-02-01

    The genes involved in choline transport and oxidation to glycine betaine in the biopesticidal bacterium Serratia entomophila were characterized, and the potential of osmoprotectants, coupled with increased NaCl concentrations, to improve the desiccation tolerance of this species was investigated. Serratia entomophila carries sequences similar to the Escherichia coli betTIBA genes encoding a choline transporter and dehydrogenase, a betaine aldehyde dehydrogenase and a regulatory protein. Disruption of betA abolished the ability of Ser. entomophila to utilize choline as a carbon source. Quantitative reverse-transcriptase PCR analysis revealed that betA transcription was reduced compared to that of the upstream genes in the operon, and that NaCl and choline induced bet gene expression. Glycine betaine and choline increased the NaCl tolerance of Ser. entomophila, and osmotically preconditioned cultures survived better than control cultures following desiccation and immediately after application to agricultural soil. Addition of glycine betaine and NaCl to growth medium can greatly enhance the desiccation survival of Ser. entomophila, and its initial survival in soil. Serratia entomophila is sensitive to desiccation and does not persist under low soil moisture conditions. Techniques described here for enhancing the desiccation survival of Ser. entomophila can be used to improve formulations of this bacterium, and allow its application under a wider range of environmental conditions. © 2012 AgResearch.

  16. Experimental evolution of bet hedging under manipulated environmental uncertainty in Neurospora crassa.

    PubMed

    Graham, Jeffrey K; Smith, Myron L; Simons, Andrew M

    2014-07-22

    All organisms are faced with environmental uncertainty. Bet-hedging theory expects unpredictable selection to result in the evolution of traits that maximize the geometric-mean fitness even though such traits appear to be detrimental over the shorter term. Despite the centrality of fitness measures to evolutionary analysis, no direct test of the geometric-mean fitness principle exists. Here, we directly distinguish between predictions of competing fitness maximization principles by testing Cohen's 1966 classic bet-hedging model using the fungus Neurospora crassa. The simple prediction is that propagule dormancy will evolve in proportion to the frequency of 'bad' years, whereas the prediction of the alternative arithmetic-mean principle is the evolution of zero dormancy as long as the expectation of a bad year is less than 0.5. Ascospore dormancy fraction in N. crassa was allowed to evolve under five experimental selection regimes that differed in the frequency of unpredictable 'bad years'. Results were consistent with bet-hedging theory: final dormancy fraction in 12 genetic lineages across 88 independently evolving samples was proportional to the frequency of bad years, and evolved both upwards and downwards as predicted from a range of starting dormancy fractions. These findings suggest that selection results in adaptation to variable rather than to expected environments. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Thermodynamic properties of antiferromagnetic ordered states of π -d interacting systems of κ -(BETS) 2Fe X4(X =Br ,Cl )

    NASA Astrophysics Data System (ADS)

    Fukuoka, Shuhei; Yamashita, Satoshi; Nakazawa, Yasuhiro; Yamamoto, Takashi; Fujiwara, Hideki; Shirahata, Takashi; Takahashi, Kazuko

    2016-06-01

    The results are presented for systematic heat capacity measurements of π-d interacting systems of κ -(BETS) 2Fe Br4 and κ -(BETS) 2FeC l4 [BETS = bis(ethylenedithio)tetraselenafulvalene] performed under in-plane magnetic fields. We observed sharp thermal anomalies at 2.47 K for κ -(BETS) 2FeB r4 and at 0.47 K for κ -(BETS) 2FeC l4 at 0 T that are associated with antiferromagnetic transitions of the 3 d electrons in the anion layers. From analyses of the magnetic heat capacity data, we indicate that the two compounds show unconventional thermodynamic behaviors inherent in the π-d interacting layered system. In the case of κ -(BETS) 2FeB r4 , a small hump structure was observed in the magnetic heat capacity below the transition temperature when a magnetic field was applied parallel to the a axis. In the case of κ -(BETS) 2FeC l4 , a similar hump structure was observed at 0 T that remained in the data with magnetic fields applied parallel to the a axis. We demonstrate that the temperature dependencies of the magnetic heat capacities scale well by normalizing the temperatures with dominant one-dimensional direct interactions (Jdd/kB) of each compound. The field dependencies of the transition temperatures and the hump structures are elucidated in one simple magnetic field vs temperature (H -T ) phase diagram. These results indicate that the thermodynamic features of both κ-type BETS salts are essentially equivalent, and the observed hump structures are derived from the one-dimensional Jdd interaction characters, which are still influential for magnetic features even in the long-range magnetic ordered states.

  18. The Transcription Factor T-Bet Is Regulated by MicroRNA-155 in Murine Anti-Viral CD8+ T Cells via SHIP-1.

    PubMed

    Hope, Jennifer L; Stairiker, Christopher J; Spantidea, Panagiota I; Gracias, Donald T; Carey, Alison J; Fike, Adam J; van Meurs, Marjan; Brouwers-Haspels, Inge; Rijsbergen, Laurine C; Fraietta, Joseph A; Mueller, Yvonne M; Klop, Rosemarieke C; Stelekati, Erietta; Wherry, E John; Erkeland, Stefan J; Katsikis, Peter D

    2017-01-01

    We report here that the expression of the transcription factor T-bet, which is known to be required for effector cytotoxic CD8 + T lymphocytes (CTL) generation and effector memory cell formation, is regulated in CTL by microRNA-155 (miR-155). Importantly, we show that the proliferative effect of miR-155 on CD8 + T cells is mediated by T-bet. T-bet levels in CTL were controlled in vivo by miR-155 via SH2 (Src homology 2)-containing inositol phosphatase-1 (SHIP-1), a known direct target of miR-155, and SHIP-1 directly downregulated T-bet. Our studies reveal an important and unexpected signaling axis between miR-155, T-bet, and SHIP-1 in in vivo CTL responses and suggest an important signaling module that regulates effector CTL immunity.

  19. Osmotic stress response in Acinetobacter baylyi: identification of a glycine-betaine biosynthesis pathway and regulation of osmoadaptive choline uptake and glycine-betaine synthesis through a choline-responsive BetI repressor.

    PubMed

    Scholz, Anica; Stahl, Julia; de Berardinis, Veronique; Müller, Volker; Averhoff, Beate

    2016-04-01

    Acinetobacter baylyi, a ubiquitous soil bacterium, can cope with high salinity by uptake of choline as precursor of the compatible solute glycine betaine. Here, we report on the identification of a choline dehydrogenase (BetA) and a glycine betaine aldehyde dehydrogenase (BetB) mediating the oxidation of choline to glycine betaine. The betAB genes were found to form an operon together with the potential transcriptional regulator betI. The transcription of the betIBA operon and the two recently identified choline transporters was upregulated in response to choline and choline plus salt. The finding that the osmo-independent transporter BetT1 undergoes a higher upregulation in response to choline alone than betT2 suggests that BetT1 does not primarily function in osmoadaptation. Electrophoretic mobility shift assays led to the conclusion that BetI mediates transcriptional regulation of both, the betIBA gene operon and the choline transporters. BetI was released from the DNA in response to choline which together with the transcriptional upregulation of the bet genes in the presence of choline suggests that BetI is a choline sensing transcriptional repressor. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. Mitotic Vulnerability in Triple-Negative Breast Cancer Associated with LIN9 Is Targetable with BET Inhibitors.

    PubMed

    Sahni, Jennifer M; Gayle, Sylvia S; Webb, Bryan M; Weber-Bonk, Kristen L; Seachrist, Darcie D; Singh, Salendra; Sizemore, Steven T; Restrepo, Nicole A; Bebek, Gurkan; Scacheri, Peter C; Varadan, Vinay; Summers, Matthew K; Keri, Ruth A

    2017-10-01

    Triple-negative breast cancers (TNBC) are highly aggressive, lack FDA-approved targeted therapies, and frequently recur, making the discovery of novel therapeutic targets for this disease imperative. Our previous analysis of the molecular mechanisms of action of bromodomain and extraterminal protein inhibitors (BETi) in TNBC revealed these drugs cause multinucleation, indicating BET proteins are essential for efficient mitosis and cytokinesis. Here, using live cell imaging, we show that BET inhibition prolonged mitotic progression and induced mitotic cell death, both of which are indicative of mitotic catastrophe. Mechanistically, the mitosis regulator LIN9 was a direct target of BET proteins that mediated the effects of BET proteins on mitosis in TNBC. Although BETi have been proposed to function by dismantling super-enhancers (SE), the LIN9 gene lacks an SE but was amplified or overexpressed in the majority of TNBCs. In addition, its mRNA expression predicted poor outcome across breast cancer subtypes. Together, these results provide a mechanism for cancer selectivity of BETi that extends beyond modulation of SE-associated genes and suggest that cancers dependent upon LIN9 overexpression may be particularly vulnerable to BETi. Cancer Res; 77(19); 5395-408. ©2017 AACR . ©2017 American Association for Cancer Research.

  1. Betting on Illusory Patterns: Probability Matching in Habitual Gamblers.

    PubMed

    Gaissmaier, Wolfgang; Wilke, Andreas; Scheibehenne, Benjamin; McCanney, Paige; Barrett, H Clark

    2016-03-01

    Why do people gamble? A large body of research suggests that cognitive distortions play an important role in pathological gambling. Many of these distortions are specific cases of a more general misperception of randomness, specifically of an illusory perception of patterns in random sequences. In this article, we provide further evidence for the assumption that gamblers are particularly prone to perceiving illusory patterns. In particular, we compared habitual gamblers to a matched sample of community members with regard to how much they exhibit the choice anomaly 'probability matching'. Probability matching describes the tendency to match response proportions to outcome probabilities when predicting binary outcomes. It leads to a lower expected accuracy than the maximizing strategy of predicting the most likely event on each trial. Previous research has shown that an illusory perception of patterns in random sequences fuels probability matching. So does impulsivity, which is also reported to be higher in gamblers. We therefore hypothesized that gamblers will exhibit more probability matching than non-gamblers, which was confirmed in a controlled laboratory experiment. Additionally, gamblers scored much lower than community members on the cognitive reflection task, which indicates higher impulsivity. This difference could account for the difference in probability matching between the samples. These results suggest that gamblers are more willing to bet impulsively on perceived illusory patterns.

  2. A hypoallergenic variant of the major birch pollen allergen shows distinct characteristics in antigen processing and T-cell activation.

    PubMed

    Kitzmüller, C; Wallner, M; Deifl, S; Mutschlechner, S; Walterskirchen, C; Zlabinger, G J; Ferreira, F; Bohle, B

    2012-11-01

    BM4 is a novel genetically engineered variant of the major birch pollen allergen Bet v 1 that lacks the typical Bet v 1-like fold and displays negligible IgE-binding but strong T cell-activating capacity. The aim of this study was to elucidate possible differences between BM4 and Bet v 1 in internalization, antigen processing, and presentation. Proliferative responses to BM4 and Bet v 1 of peripheral blood mononuclear cells and Bet v 1-specific T-cell clones were compared. Fluorescently labeled BM4 and Bet v 1 were used to study surface binding, endocytosis, and intracellular degradation by monocyte-derived DC (mdDC). Both proteins were digested by endolysosomal extracts of mdDC. BM4- and Bet v 1-pulsed mdDC were employed to assess the kinetics of activation of Bet v 1-specific T-cell clones and the polarization of naïve T cells. BM4 displayed a significantly stronger T cell-activating capacity than Bet v 1. Furthermore, BM4 showed increased surface binding and internalization as well as faster endolysosomal degradation compared with Bet v 1. BM4-pulsed mdDC induced enhanced proliferative responses at earlier time-points in Bet v 1-specific T-cell clones and promoted less IL-5 production in T cells than Bet v 1-pulsed mdDC. The loss of the Bet v 1-fold changes the protein's interaction with the human immune system at the level of antigen-presenting cells resulting in altered T-cell responses. By combining low IgE-binding with strong and modulating T cell-activating capacity, BM4 represents a highly interesting candidate for specific immunotherapy of birch pollen allergy. © 2012 John Wiley & Sons A/S.

  3. PyBetVH: A Python tool for probabilistic volcanic hazard assessment and for generation of Bayesian hazard curves and maps

    NASA Astrophysics Data System (ADS)

    Tonini, Roberto; Sandri, Laura; Anne Thompson, Mary

    2015-06-01

    PyBetVH is a completely new, free, open-source and cross-platform software implementation of the Bayesian Event Tree for Volcanic Hazard (BET_VH), a tool for estimating the probability of any magmatic hazardous phenomenon occurring in a selected time frame, accounting for all the uncertainties. New capabilities of this implementation include the ability to calculate hazard curves which describe the distribution of the exceedance probability as a function of intensity (e.g., tephra load) on a grid of points covering the target area. The computed hazard curves are (i) absolute (accounting for the probability of eruption in a given time frame, and for all the possible vent locations and eruptive sizes) and (ii) Bayesian (computed at different percentiles, in order to quantify the epistemic uncertainty). Such curves allow representation of the full information contained in the probabilistic volcanic hazard assessment (PVHA) and are well suited to become a main input to quantitative risk analyses. PyBetVH allows for interactive visualization of both the computed hazard curves, and the corresponding Bayesian hazard/probability maps. PyBetVH is designed to minimize the efforts of end users, making PVHA results accessible to people who may be less experienced in probabilistic methodologies, e.g. decision makers. The broad compatibility of Python language has also allowed PyBetVH to be installed on the VHub cyber-infrastructure, where it can be run online or downloaded at no cost. PyBetVH can be used to assess any type of magmatic hazard from any volcano. Here we illustrate how to perform a PVHA through PyBetVH using the example of analyzing tephra fallout from the Okataina Volcanic Centre (OVC), New Zealand, and highlight the range of outputs that the tool can generate.

  4. Within-and among-year germination in Sonoran Desert winter annuals: bet hedging and predictive germination in a variable environment.

    PubMed

    Gremer, Jennifer R; Kimball, Sarah; Venable, D Lawrence

    2016-10-01

    In variable environments, organisms must have strategies to ensure fitness as conditions change. For plants, germination can time emergence with favourable conditions for later growth and reproduction (predictive germination), spread the risk of unfavourable conditions (bet hedging) or both (integrated strategies). Here we explored the adaptive value of within- and among-year germination timing for 12 species of Sonoran Desert winter annual plants. We parameterised models with long-term demographic data to predict optimal germination fractions and compared them to observed germination. At both temporal scales we found that bet hedging is beneficial and that predicted optimal strategies corresponded well with observed germination. We also found substantial fitness benefits to varying germination timing, suggesting some degree of predictive germination in nature. However, predictive germination was imperfect, calling for some degree of bet hedging. Together, our results suggest that desert winter annuals have integrated strategies combining both predictive plasticity and bet hedging. © 2016 John Wiley & Sons Ltd/CNRS.

  5. Norcoclaurine synthase is a member of the pathogenesis-related 10/Bet v1 protein family.

    PubMed

    Lee, Eun-Jeong; Facchini, Peter

    2010-10-01

    Norcoclaurine synthase (NCS) catalyzes the first committed step in the biosynthesis of benzylisoquinoline alkaloids (BIAs). NCS from Thalictrum flavum (Tf NCS), Papaver somniferum (Ps NCS1 and Ps NCS2), and Coptis japonica (Cj PR10A) share substantial identity with pathogen-related 10 (PR10) and Bet v1 proteins, whose functions are not well understood. A distinct enzyme (Cj NCS1) with similarity to 2-oxoglutarate-dependent dioxygenases was suggested as the bona fide NCS in C. japonica. Here, we validate the exclusive role of PR10/Bet v1-type NCS enzymes in BIA metabolism. Immunolocalization of Ps NCS2 revealed its cell type-specific occurrence in phloem sieve elements, which contain all other known BIA biosynthetic enzymes. In opium poppy, NCS transcripts and proteins were abundant in root and stem, but at low levels in leaf and carpel. Silencing of NCS in opium poppy profoundly reduced alkaloid levels compared with controls. Immunoprecipitation of NCS from total protein extracts of T. flavum cells resulted in a nearly complete attenuation of NCS activity. A Ps NCS2-green fluorescent protein fusion introduced by microprojectile bombardment into opium poppy cells initially localized to the endoplasmic reticulum but subsequently sorted to the vacuole. In our hands, Cj NCS1 did not catalyze the formation of (S)-norcoclaurine from dopamine and 4-hydroxyphenylacetaldehyde.

  6. Mitochondrial protection impairs BET bromodomain inhibitor-mediated cell death and provides rationale for combination therapeutic strategies.

    PubMed

    Lasorsa, E; Smonksey, M; Kirk, J S; Rosario, S; Hernandez-Ilizaliturri, F J; Ellis, L

    2015-12-10

    Inhibitors of the bromodomain and extraterminal domain family (BETI) have recently entered phase I clinical trials. In patients with advanced leukemia's, potent antileukemia activity was displayed with minimum dose-limiting toxicity. In preclinical models of hematological malignancies, including aggressive B-cell lymphomas, BETI induced cell-cycle arrest and apoptosis. However, the underlying cell death mechanisms are still not well understood. Dissecting the mechanisms required by BETI to mediate cell death would provide strong direction on how to best utilize BETI to treat patients with aggressive hematological malignancies. Herein, we provide understanding of the molecular mechanisms underlying BETI-mediated cell death using I-BET762. Induction of cell death occurred in primary murine and human B-cell lymphomas through apoptosis. Genetic dissection using Eμ-myc B-cell lymphoma compound mutants demonstrated that I-BET762-induced apoptosis does not require the p53 pathway. Furthermore, deletion of Apaf1, and thus the absence of a functional apoptosome, is associated with a delayed drug response but do not provide long-term resistance. Prolonged treatment of this model in fact fails to suppress the therapeutic efficacy of the drug and is associated with biochemical features of autophagy. However, lack of mitochondrial permeability completely inhibited I-BET762-mediated tumor cell death, indicating mitochondrial damage as key events for its activity. Combination of I-BET762 with BH3-only mimetics ABT-263 or obatoclax, restored sensitivity to I-BET762 lymphoma killing; however, success was determined by expression of Bcl-2 family antiapoptotic proteins. Our study provides critical insight for clinical decisions regarding the appropriate strategy for using BETI as a single agent or in combination to treat patients with aggressive B-cell lymphomas.

  7. Therapeutic Mechanism of BET Bromodomain Inhibitor in Breast

    DTIC Science & Technology

    2015-12-01

    evaluated the performance of this model in predicting gene expression changes associated with 3h,12h and 24h of JQ1 treatment and found that BRD4 ChIP- seq...models of cancer4–6, have not been evaluated in TNBC. These inhibitors displace BET bromodomain proteins such as BRD4 from chromatin by competing...Extended Data Fig. 2c, d and Fig. 1b). Extending the translational significance of these findings, we evalu - ated the ability of JQ1 to inhibit tumour

  8. 'Put Your Money Where Your Mouth Is!': Effects of Streaks on Confidence and Betting in a Binary Choice Task.

    PubMed

    Studer, Bettina; Limbrick-Oldfield, Eve H; Clark, Luke

    2015-07-01

    Human choice under uncertainty is influenced by erroneous beliefs about randomness. In simple binary choice tasks, such as red/black predictions in roulette, long outcome runs (e.g. red, red, red) typically increase the tendency to predict the other outcome (i.e. black), an effect labeled the "gambler's fallacy." In these settings, participants may also attend to streaks in their predictive performance. Winning and losing streaks are thought to affect decision confidence, although prior work indicates conflicting directions. Over three laboratory experiments involving red/black predictions in a sequential roulette task, we sought to identify the effects of outcome runs and winning/losing streaks upon color predictions, decision confidence and betting behavior. Experiments 1 ( n  = 40) and 3 ( n  = 40) obtained trial-by-trial confidence ratings, with a win/no win payoff and a no loss/loss payoff, respectively. Experiment 2 ( n  = 39) obtained a trial-by-trial bet amount on an equivalent scale. In each experiment, the gambler's fallacy was observed on choice behavior after color runs and, in experiment 2, on betting behavior after color runs. Feedback streaks exerted no reliable influence on confidence ratings, in either payoff condition. Betting behavior, on the other hand, increased as a function of losing streaks. The increase in betting on losing streaks is interpreted as a manifestation of loss chasing; these data help clarify the psychological mechanisms underlying loss chasing and caution against the use of betting measures ("post-decision wagering") as a straightforward index of decision confidence. © 2014 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd.

  9. The bromodomain protein inhibitor I-BET151 suppresses expression of inflammatory genes and matrix degrading enzymes in rheumatoid arthritis synovial fibroblasts.

    PubMed

    Klein, Kerstin; Kabala, Pawel A; Grabiec, Aleksander M; Gay, Renate E; Kolling, Christoph; Lin, Lih-Ling; Gay, Steffen; Tak, Paul P; Prinjha, Rab K; Ospelt, Caroline; Reedquist, Kris A

    2016-02-01

    To investigate the effects of BET bromodomain protein inhibition on inflammatory activation and functional properties of rheumatoid arthritis synovial fibroblasts (RASF). The expression of the BET bromodomain proteins BRD2, BRD3 and BRD4 was analysed in synovial tissue by immunohistochemistry. RASF were stimulated with tumour necrosis factor (TNF)-α, interleukin (IL)-1β and toll-like receptor (TLR) ligands (Pam3, pIC and lipopolysaccharide (LPS)) in the presence or absence of the BET inhibitor I-BET151, or siRNA targeting BRD2, BRD3 and BRD4. RASF expression of inflammatory mediators, including MMP1, MMP3, IL-6 and IL-8, was measured by q-PCR, q-PCR array and ELISA. Cellular viability, apoptosis, proliferation and chemoattractive properties of RASF were investigated using MTT, cell apoptosis ELISA, BrdU-based proliferation and transwell migration assays. BRD2, BRD3 and BRD4 proteins were detected in rheumatoid arthritis (RA) synovial tissue, expressed in both RASF and macrophages. I-BET151 suppressed cytokine and TLR ligand-induced secretion of MMP1, MMP3, IL-6 and IL-8, and mRNA expression of more than 70% of genes induced by TNF-α and IL-1β. Combined silencing of BRD2, BRD3 and BRD4 significantly reduced cytokine and TLR ligand-induced expression of a subset of gene products targeted by I-BET151, including MMP1, CXCL10 and CXCL11. I-BET151 treatment of RASF reduced RASF proliferation, and the chemotactic potential for peripheral blood leucocytes of RASF conditioned medium. Inhibition of BET family proteins suppresses the inflammatory, matrix-degrading, proliferative and chemoattractive properties of RASF and suggests a therapeutic potential in the targeting of epigenetic reader proteins in RA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Benzoxazinone-containing 3,5-dimethylisoxazole derivatives as BET bromodomain inhibitors for treatment of castration-resistant prostate cancer.

    PubMed

    Xue, Xiaoqian; Zhang, Yan; Wang, Chao; Zhang, Maofeng; Xiang, Qiuping; Wang, Junjian; Wang, Anhui; Li, Chenchang; Zhang, Cheng; Zou, Lingjiao; Wang, Rui; Wu, Shuang; Lu, Yongzhi; Chen, Hongwu; Ding, Ke; Li, Guohui; Xu, Yong

    2018-04-21

    The bromodomain and extra-terminal proteins (BET) have emerged as promising therapeutic targets for the treatment of castration-resistant prostate cancer (CRPC). We report the design, synthesis and evaluation of a new series of benzoxazinone-containing 3,5-dimethylisoxazole derivatives as selective BET inhibitors. One of the new compounds, (R)-12 (Y02234), binds to BRD4(1) with a K d value of 110 nM and blocks bromodomain and acetyl lysine interactions with an IC 50 value of 100 nM. It also exhibits selectivity for BET over non-BET bromodomain proteins and demonstrates reasonable anti-proliferation and colony formation inhibition effect in prostate cancer cell lines such as 22Rv1 and C4-2B. The BRD4 inhibitor (R)-12 also significantly suppresses the expression of ERG, Myc and AR target gene PSA at the mRNA level in prostate cancer cells. Treatment with (R)-12 significantly suppresses the tumor growth of prostate cancer (TGI = 70%) in a 22Rv1-derived xenograft model. These data suggest that compound (R)-12 is a promising lead compound for the development of a new class of therapeutics for the treatment of CRPC. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  11. Substrate-bound outward-open state of the betaine transporter BetP provides insights into Na+ coupling

    NASA Astrophysics Data System (ADS)

    Perez, Camilo; Faust, Belinda; Mehdipour, Ahmad Reza; Francesconi, Kevin A.; Forrest, Lucy R.; Ziegler, Christine

    2014-07-01

    The Na+-coupled betaine symporter BetP shares a highly conserved fold with other sequence unrelated secondary transporters, for example, with neurotransmitter symporters. Recently, we obtained atomic structures of BetP in distinct conformational states, which elucidated parts of its alternating-access mechanism. Here, we report a structure of BetP in a new outward-open state in complex with an anomalous scattering substrate, adding a fundamental piece to an unprecedented set of structural snapshots for a secondary transporter. In combination with molecular dynamics simulations these structural data highlight important features of the sequential formation of the substrate and sodium-binding sites, in which coordinating water molecules play a crucial role. We observe a strictly interdependent binding of betaine and sodium ions during the coupling process. All three sites undergo progressive reshaping and dehydration during the alternating-access cycle, with the most optimal coordination of all substrates found in the closed state.

  12. Power-law distribution in Japanese racetrack betting

    NASA Astrophysics Data System (ADS)

    Ichinomiya, Takashi

    2006-08-01

    Gambling is one of the basic economic activities that humans indulge in. An investigation of gambling activities provides deep insights into the economic actions of people and sheds lights on the study of econophysics. In this paper we present an analysis of the distribution of the final odds of the races organized by the Japan Racing Association. The distribution of the final odds Po(x) indicates a clear power-law Po(x)∝1/x, where x represents the final odds. This power-law can be explained on the basis of the assumption that every bettor bets his money on the horse that appears to be the strongest in a race.

  13. BASALIT trial: double-blind placebo-controlled allergen immunotherapy with rBet v 1-FV in birch-related soya allergy.

    PubMed

    Treudler, R; Franke, A; Schmiedeknecht, A; Ballmer-Weber, B; Worm, M; Werfel, T; Jappe, U; Biedermann, T; Schmitt, J; Brehler, R; Kleinheinz, A; Kleine-Tebbe, J; Brüning, H; Ruëff, F; Ring, J; Saloga, J; Schäkel, K; Holzhauser, T; Vieths, S; Simon, J C

    2017-08-01

    Conflicting results exist on the effect of allergen immunotherapy (AIT) on pollen-related food allergy. We aimed to investigate the efficacy of one-year AIT with the folding variant (FV) of recombinant (r) Bet v 1 on birch-related soya allergy. Of 138 subjects with Bet v 1 sensitization, 82 were positive at double-blind placebo-controlled food challenge (DBPCFC) with soya. A total of 56 of 82 were randomized in the ratio of 2:1 (active: placebo). Per-protocol population (PPP) had received ≥150 μg of allergen or placebo preparation. lowest observed adverse effect levels (LOAEL), postinterventional occurrence of objective signs (objS) at any dose level, sIgE/IgG4 against Bet v 1 and Gly m 4. Between-group changes were investigated (ancova, Mann-Whitney U-test, Fisher exact test). Baseline characteristics including LOAELs were comparable in both groups with objS and subjS occurring in 82% and 95% of active (n = 38) vs 78% and 83% of placebo group (n = 18). After AIT, objS occurred in 24% and 47%, respectively. LOAEL group differences showed a beneficial tendency (P = 0.081) for LOAEL objective in PPP (30 active, 15 placebo). sIgG4 raised only in active group (Bet v 1: P = 0.054, Gly m 4: P = 0.037), and no relevant changes occurred for sIgE. Only 56% of the intended sample size was recruited. For the first time, we present data on the effect of rBet v 1-FV on birch-related soya allergy. rBet v 1-FV AIT induced significant immunogenic effects. Clinical assessment showed a tendency in favour of the active group but did not reach statistical significance. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Imiquimod-induced psoriasis-like skin inflammation is suppressed by BET bromodomain inhibitor in mice through RORC/IL-17A pathway modulation.

    PubMed

    Nadeem, Ahmed; Al-Harbi, Naif O; Al-Harbi, Mohamed M; El-Sherbeeny, Ahmed M; Ahmad, Sheikh F; Siddiqui, Nahid; Ansari, Mushtaq A; Zoheir, Khairy M A; Attia, Sabry M; Al-Hosaini, Khaled A; Al-Sharary, Shakir D

    2015-09-01

    Psoriasis is one of the most common skin disorders characterized by erythematous plaques that result from hyperproliferative keratinocytes and infiltration of inflammatory leukocytes into dermis and epidermis. Recent studies suggest that IL-23/IL-17A/IL-22 cytokine axis plays an important role in the pathogenesis of psoriasis. The small molecule bromodomain and extraterminal domain (BET) inhibitors, that disrupt interaction of BET proteins with acetylated histones have recently demonstrated efficacy in various models of inflammation through suppression of several pathways, one of them being synthesis of IL-17A/IL-22 which primarily depends on transcription factor, retinoic acid receptor-related orphan receptor C (RORC). However, the efficacy and mechanistic aspect of a BET inhibitor in mouse model of skin inflammation has not been explored previously. Therefore, this study investigated the role of BET inhibitor, JQ-1 in mouse model of psoriasis-like inflammation. Mice were topically applied imiquimod (IMQ) to develop psoriasis-like inflammation on the shaved back and ear followed by assessment of skin inflammation (myeloperoxidase activity, ear thickness, and histopathology), RORC and its signature cytokines (IL-17A/IL-22). JQ-1 suppressed IMQ-induced skin inflammation as reflected by a decrease in ear thickness/myeloperoxidase activity, and RORC/IL-17A/IL-22 expression. Additionally, a RORα/γ agonist SR1078 was utilized to investigate the role of RORC in BET-mediated skin inflammation. SR1078 reversed the protective effect of JQ-1 on skin inflammation at both histological and molecular levels in the IMQ model. The current study suggests that BET bromodomains are involved in psoriasis-like inflammation through induction of RORC/IL-17A pathway. Therefore, inhibition of BET bromodomains may provide a new therapy against skin inflammation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthesis of mesoporous cerium compound for CO2 capture

    NASA Astrophysics Data System (ADS)

    Liu, Guiqing; Tatsuda, Kou; Yoneyama, Yoshiharu; Tsubaki, Noritatsu

    2017-11-01

    A mesoporous adsorbent was simply synthesized by adding alkaline substances to cerium(III) nitric hydrate. The surface characteristics of the synthesized cerium compound were determined with BET, XRD and TEM analysis. It was found that although the specific surface areas of the synthesized cerium compounds were among about 120-200m2 per gram (BET area) which were smaller than the common used zeolite 13X (BET area 743 m2/g) and activated carbon (BET area 1079 m2/g), but the cerium compounds had excellent performances for CO2 adsorption as well as the CO2 desorption.

  16. Modeling combination therapy for breast cancer with BET and immune checkpoint inhibitors.

    PubMed

    Lai, Xiulan; Stiff, Andrew; Duggan, Megan; Wesolowski, Robert; Carson, William E; Friedman, Avner

    2018-05-07

    CTLA-4 is an immune checkpoint expressed on active anticancer T cells. When it combines with its ligand B7 on dendritic cells, it inhibits the activity of the T cells. The Bromo- and Extra-Terminal (BET) protein family includes proteins that regulate the expression of key oncogenes and antiapoptotic proteins. BET inhibitor (BETi) has been shown to reduce the expression of MYC by suppressing its transcription factors and to down-regulate the hypoxic transcriptome response to VEGF-A. This paper develops a mathematical model of the treatment of cancer by combination therapy of BETi and CTLA-4 inhibitor. The model shows that the two drugs are positively correlated in the sense that the tumor volume decreases as the dose of each of the drugs is increased. The model also considers the effect of the combined therapy on levels of myeloid-derived suppressor cells (MDSCs) and the overexpression of TNF-[Formula: see text], which may predict gastrointestinal side effects of the combination.

  17. Surface area and pore size characteristics of nanoporous gold subjected to thermal, mechanical, or surface modification studied using gas adsorption isotherms, cyclic voltammetry, thermogravimetric analysis, and scanning electron microscopy

    PubMed Central

    Tan, Yih Horng; Davis, Jason A.; Fujikawa, Kohki; Ganesh, N. Vijaya; Demchenko, Alexei V.

    2012-01-01

    Nitrogen adsorption/desorption isotherms are used to investigate the Brunauer, Emmett, and Teller (BET) surface area and Barrett-Joyner-Halenda (BJH) pore size distribution of physically modified, thermally annealed, and octadecanethiol functionalized np-Au monoliths. We present the full adsorption-desorption isotherms for N2 gas on np-Au, and observe type IV isotherms and type H1 hysteresis loops. The evolution of the np-Au under various thermal annealing treatments was examined using scanning electron microscopy (SEM). The images of both the exterior and interior of the thermally annealed np-Au show that the porosity of all free standing np-Au structures decreases as the heat treatment temperature increases. The modification of the np-Au surface with a self-assembled monolayer (SAM) of C18-SH (coverage of 2.94 × 1014 molecules cm−2 based from the decomposition of the C18-SH using thermogravimetric analysis (TGA)), was found to reduce the strength of the interaction of nitrogen gas with the np-Au surface, as reflected by a decrease in the ‘C’ parameter of the BET equation. From cyclic voltammetry studies, we found that the surface area of the np-Au monoliths annealed at elevated temperatures followed the same trend with annealing temperature as found in the BET surface area study and SEM morphology characterization. The study highlights the ability to control free-standing nanoporous gold monoliths with high surface area, and well-defined, tunable pore morphology. PMID:22822294

  18. ‘Put Your Money Where Your Mouth Is!’: Effects of Streaks on Confidence and Betting in a Binary Choice Task

    PubMed Central

    Studer, Bettina; Limbrick-Oldfield, Eve H; Clark, Luke

    2015-01-01

    Human choice under uncertainty is influenced by erroneous beliefs about randomness. In simple binary choice tasks, such as red/black predictions in roulette, long outcome runs (e.g. red, red, red) typically increase the tendency to predict the other outcome (i.e. black), an effect labeled the “gambler's fallacy.” In these settings, participants may also attend to streaks in their predictive performance. Winning and losing streaks are thought to affect decision confidence, although prior work indicates conflicting directions. Over three laboratory experiments involving red/black predictions in a sequential roulette task, we sought to identify the effects of outcome runs and winning/losing streaks upon color predictions, decision confidence and betting behavior. Experiments 1 (n = 40) and 3 (n = 40) obtained trial-by-trial confidence ratings, with a win/no win payoff and a no loss/loss payoff, respectively. Experiment 2 (n = 39) obtained a trial-by-trial bet amount on an equivalent scale. In each experiment, the gambler's fallacy was observed on choice behavior after color runs and, in experiment 2, on betting behavior after color runs. Feedback streaks exerted no reliable influence on confidence ratings, in either payoff condition. Betting behavior, on the other hand, increased as a function of losing streaks. The increase in betting on losing streaks is interpreted as a manifestation of loss chasing; these data help clarify the psychological mechanisms underlying loss chasing and caution against the use of betting measures (“post-decision wagering”) as a straightforward index of decision confidence. © 2014 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd. PMID:26236092

  19. A comparative content analysis of media reporting of sports betting in Australia: lessons for public health media advocacy approaches.

    PubMed

    David, Jennifer L; Thomas, Samantha L; Randle, Melanie; Bowe, Steven J; Daube, Mike

    2017-11-14

    Harmful gambling is a significant public health issue. There has been widespread discussion in the Australian media about the extent and impact of sports betting on the Australian community, particularly relating to young men and children. Given the role that the media plays in influencing policy change and political agendas, and the acknowledgement that media based advocacy is a fundamental component of successful advocacy campaigns, this research aimed to investigate how different stakeholder groups discuss sports betting within the Australian print media. The study uses this information to provide recommendations to guide public health media advocacy approaches. A quantitative content analysis of print media articles was conducted during two significant Parliamentary Inquiries about sports betting - (1) The Joint Select Committee Inquiry into the Advertising and Promotion of Gambling Services in Sport (2012/2013), and (2) 'The Review of Illegal Offshore Wagering (2015/2016). A total of 241 articles from 12 daily Australian newspapers were analysed. Statistical analysis was used to compare frequency of, and changes in, themes, voices and perspectives over time. Discussions about the marketing and communication of sports betting was a main theme in media reporting (n = 165, 68.5%), while discussions about gambling reform decreased significantly across the two time periods (p < 0.0001). The presence of sports betting industry (p < 0.0001), sporting code (p < 0.0001) and public health expert (p = 0.001) voices all increased significantly across the two time periods. There were very few (n = 11, 4.6%) voices from those who had experienced gambling harm. Finally, while there were significantly fewer articles taking the perspective that regulation changes were needed to protect vulnerable sub-populations (p < 0.0001), articles that had a neutral perspective about the need for regulation change increased significantly across the two time periods (p < 0

  20. 15. 'Southern Pacific R.R., One 236'0' Bet. End Pins S. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. 'Southern Pacific R.R., One 236'-0' Bet. End Pins S. Tr. Thro'. Draw Bridge over Sacramento River at Tehama, The Phoenix Bridge Co., Phoenixville, Pa., Jan'y 19th 98, Dwg. 585.' - Southern Pacific Railroad Shasta Route, Bridge No. 210.52, Milepost 210.52, Tehama, Tehama County, CA

  1. Estimation of reactive surface area using a combined method of laboratory analyses and digital image processing

    NASA Astrophysics Data System (ADS)

    Ma, Jin; Kong, Xiang-Zhao; Saar, Martin O.

    2017-04-01

    Fluid-rock interactions play an important role in the engineering processes such as chemical stimulation of enhanced geothermal systems and carbon capture, utilization, and storage. However, these interactions highly depend on the accessible reactive surface area of the minerals that are generally poorly constrained for natural geologic samples. In particular, quantifying surface area of each reacting mineral within whole rock samples is challenging due to the heterogeneous distribution of minerals and pore space. In this study, detailed laboratory analyses were performed on sandstone samples from deep geothermal sites in Lithuania. We measure specific surface area of whole rock samples using a gas adsorption method (so-called B.E.T.) with N2 at a temperature of 77.3K. We also quantify their porosity and pore size distribution by a Helium gas pycnometer and a Hg porosimetry, respectively. Rock compositions are determined by a combination of X-ray fluorescence (XRF) and quantitative scanning electron microscopy (SEM) - Energy-dispersive X-ray spectroscopy (EDS), which are later geometrically mapped on images of two-dimensional SEM- Backscattered electrons (BSE) with a resolution of 1.2 μm and three-dimensional micro-CT with a resolution of 10.3 μm to produce a digital mineral map for further constraining the accessibility of reactive minerals. Moreover, we attempt to link the whole rock porosity, pore size distribution, and B.E.T. specific surface area with the digital mineral maps. We anticipate these necessary analyses to provide in-depth understanding of fluid sample chemistry from later hydrothermal reactive flow-through experiments on whole rock samples at elevated pressure and temperature.

  2. Enhanced Imaging of Specific Cell-Surface Glycosylation Based on Multi-FRET.

    PubMed

    Yuan, Baoyin; Chen, Yuanyuan; Sun, Yuqiong; Guo, Qiuping; Huang, Jin; Liu, Jianbo; Meng, Xiangxian; Yang, Xiaohai; Wen, Xiaohong; Li, Zenghui; Li, Lie; Wang, Kemin

    2018-05-15

    Cell-surface glycosylation contains abundant biological information that reflects cell physiological state, and it is of great value to image cell-surface glycosylation to elucidate its functions. Here we present a hybridization chain reaction (HCR)-based multifluorescence resonance energy transfer (multi-FRET) method for specific imaging of cell-surface glycosylation. By installing donors through metabolic glycan labeling and acceptors through aptamer-tethered nanoassemblies on the same glycoconjugate, intramolecular multi-FRET occurs due to near donor-acceptor distance. Benefiting from amplified effect and spatial flexibility of the HCR nanoassemblies, enhanced multi-FRET imaging of specific cell-surface glycosylation can be obtained. With this HCR-based multi-FRET method, we achieved obvious contrast in imaging of protein-specific GalNAcylation on 7211 cell surfaces. In addition, we demonstrated the general applicability of this method by visualizing the protein-specific sialylation on CEM cell surfaces. Furthermore, the expression changes of CEM cell-surface protein-specific sialylation under drug treatment was accurately monitored. This developed imaging method may provide a powerful tool in researching glycosylation functions, discovering biomarkers, and screening drugs.

  3. Do you make a difference? Social context in a betting task

    PubMed Central

    Nelson, Eric E.; Pine, Daniel S.; Ernst, Monique

    2008-01-01

    Social context strongly influences human motivated behavior. The triadic model implicates three major nodes in the regulation of motivated behavior, i.e. amygdala, medial prefrontal cortex (mPFC) and striatum. The present work examines how social context modulates this system. Nineteen healthy subjects completed an event-related functional magnetic resonance imaging study of a monetary betting task in the presence (social trials) and in the absence of a social peer (nonsocial trials). In the social trials, the scanned subject played along with another subject, although their performances were independent from one another. In the nonsocial trials the scanned subject played alone. Although behavioral performance did not differ between social and nonsocial trials, BOLD signal changes during betting were significantly greater in the amygdala bilaterally and the right dorsolateral prefrontal cortex (BA 9) in the social condition relative to the nonsocial condition. In contrast, activation was greater in ventral striatum in the nonsocial condition relative to the social condition. These findings suggest that social context modulates the triadic neural-systems ensemble to adjust motivated behavior to the unique demands associated with the presence of conspecifics. PMID:19015081

  4. Unusual poly(3-hydroxyalkanoate) (PHA) biosynthesis behavior of Pseudomonas putida Bet001 and Delftia tsuruhatensis Bet002 isolated from palm oil mill effluent.

    PubMed

    Razaif-Mazinah, Mohd Rafais Mohd; Anis, Siti Nor Syairah; Harun, Hazwani Izzati; Rashid, Khairunnisa Abdul; Annuar, Mohamad Suffian Mohamad

    2017-03-01

    Pseudomonas putida Bet001 and Delftia tsuruhatensis Bet002, isolated from palm oil mill effluent, accumulated poly(3-hydroxyalkanoates) (PHAs) when grown on aliphatic fatty acids, sugars, and glycerol. The substrates were supplied at 20:1 C/N mole ratio. Among C-even n-alkanoic acids, myristic acid gave the highest PHA content 26 and 28 wt% in P. putida and D. tsuruhatensis, respectively. Among C-odd n-alkanoic acids, undecanoic gave the highest PHA content at 40 wt% in P. putida and 46 wt% in D. tsuruhatensis on pentadecanoic acid. Sugar and glycerol gave <10 wt% of PHA content for both bacteria. Interestingly, D. tsuruhatensis accumulated both short- and medium-chain length PHA when supplied with n-alkanoic acids ranging from octanoic to lauric, sucrose, and glycerol with 3-hydroxybutyrate as the major monomer unit. In P. putida, the major hydroxyalkanoates unit was 3-hydroxyoctanoate and 3-hydroxydecanoate when grown on C-even acids. Conversely, 3-hydroxyheptanoate, 3-hydrxoynonanoate, and 3-hydroxyundecanoate were accumulated with C-odd acids. Weight-averaged molecular weight (M w ) was in the range of 53-81 kDa and 107-415 kDa for P. putida and D. tsuruhatensis, respectively. Calorimetric analyses indicated that both bacteria synthesized semicrystalline polymer with good thermal stability with degradation temperature (T d ) ranging from 178 to 282 °C. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  5. Surface LAMP-2 Is an Endocytic Receptor That Diverts Antigen Internalized by Human Dendritic Cells into Highly Immunogenic Exosomes.

    PubMed

    Leone, Dario Armando; Peschel, Andrea; Brown, Markus; Schachner, Helga; Ball, Miriam J; Gyuraszova, Marianna; Salzer-Muhar, Ulrike; Fukuda, Minoru; Vizzardelli, Caterina; Bohle, Barbara; Rees, Andrew J; Kain, Renate

    2017-07-15

    The lysosome-associated membrane protein (LAMP) family includes the dendritic cell endocytic receptors DC-LAMP and CD68, as well as LAMP-1 and LAMP-2. In this study we identify LAMP-1 (CD107a) and LAMP-2 (CD107b) on the surface of human monocyte-derived dendritic cells (MoDC) and show only LAMP-2 is internalized after ligation by specific Abs, including H4B4, and traffics rapidly but transiently to the MHC class II loading compartment, as does Ag conjugated to H4B4. However, pulsing MoDC with conjugates of primary (keyhole limpet hemocyanin; KLH) and recall (Bet v 1) Ags (H4B4*KLH and H4B4*Bet v 1) induced significantly less CD4 cell proliferation than pulsing with native Ag or Ag conjugated to control mAb (ISO*KLH and ISO*Bet v 1). In H4B4*KLH-pulsed MoDC, the duration of KLH residence in MHC class II loading compartments was significantly reduced, as were surface HLA-DR and DR-bound KLH-derived peptides. Paradoxically, MoDC pulsed with H4B4*KLH, but not the other KLH preparations, induced robust proliferation of CD4 cells separated from them by a transwell membrane, indicating factors in the supernatant were responsible. Furthermore, extracellular vesicles from supernatants of H4B4*KLH-pulsed MoDC contained significantly more HLA-DR and KLH than those purified from control MoDC, and KLH was concentrated specifically in exosomes that were a uniquely effective source of Ag in standard T cell proliferation assays. In summary, we identify LAMP-2 as an endocytic receptor on human MoDC that routes cargo into unusual Ag processing pathways, which reduces surface expression of Ag-derived peptides while selectively enriching Ag within immunogenic exosomes. This novel pathway has implications for the initiation of immune responses both locally and at distant sites. Copyright © 2017 by The American Association of Immunologists, Inc.

  6. Novel BET protein proteolysis-targeting chimera exerts superior lethal activity than bromodomain inhibitor (BETi) against post-myeloproliferative neoplasm secondary (s) AML cells.

    PubMed

    Saenz, D T; Fiskus, W; Qian, Y; Manshouri, T; Rajapakshe, K; Raina, K; Coleman, K G; Crew, A P; Shen, A; Mill, C P; Sun, B; Qiu, P; Kadia, T M; Pemmaraju, N; DiNardo, C; Kim, M-S; Nowak, A J; Coarfa, C; Crews, C M; Verstovsek, S; Bhalla, K N

    2017-09-01

    The PROTAC (proteolysis-targeting chimera) ARV-825 recruits bromodomain and extraterminal (BET) proteins to the E3 ubiquitin ligase cereblon, leading to degradation of BET proteins, including BRD4. Although the BET-protein inhibitor (BETi) OTX015 caused accumulation of BRD4, treatment with equimolar concentrations of ARV-825 caused sustained and profound depletion (>90%) of BRD4 and induced significantly more apoptosis in cultured and patient-derived (PD) CD34+ post-MPN sAML cells, while relatively sparing the CD34+ normal hematopoietic progenitor cells. RNA-Seq, Reverse Phase Protein Array and mass cytometry 'CyTOF' analyses demonstrated that ARV-825 caused greater perturbations in messenger RNA (mRNA) and protein expressions than OTX015 in sAML cells. Specifically, compared with OTX015, ARV-825 treatment caused more robust and sustained depletion of c-Myc, CDK4/6, JAK2, p-STAT3/5, PIM1 and Bcl-xL, while increasing the levels of p21 and p27. Compared with OTX015, PROTAC ARV-771 treatment caused greater reduction in leukemia burden and further improved survival of NSG mice engrafted with luciferase-expressing HEL92.1.7 cells. Co-treatment with ARV-825 and JAK inhibitor ruxolitinib was synergistically lethal against established and PD CD34+ sAML cells. Notably, ARV-825 induced high levels of apoptosis in the in vitro generated ruxolitinib-persister or ruxolitinib-resistant sAML cells. These findings strongly support the in vivo testing of the BRD4-PROTAC based combinations against post-MPN sAML.

  7. Best-bet integrated strategies for containing drug-resistant trypanosomes in cattle

    PubMed Central

    2012-01-01

    Background African animal trypanosomosis is a major constraint to the rearing of productive livestock in the sub-humid Sudan-Sahel zone of West Africa where cotton is grown. Trypanosomosis is mainly controlled using trypanocidal drugs, but the effective use of drugs is threatened by the development of widespread resistance. This study tested integrated best-bet strategies for containment and/ or reversal of trypanocide resistance in villages in south-east Mali where resistance has been reported. Methods Four sentinel villages each from an intervention area (along the road from Mali to Burkina Faso) and a control area (along the road from Mali to Côte d’Ivoire) were selected for the study. Tsetse control was based on deltamethrin-treated stationary attractive devices and targeted cattle spraying between March 2008 and November 2009. Trypanosome-positive cattle were selectively treated with 3.5 mg/kg diminazene aceturate. Strategic helminth control using 10 mg/kg albendazole was also undertaken. During the intervention, tsetse densities along drainage lines, trypanosome infections and faecal egg counts in risk cattle (3 to 12 months of age) were monitored. Results Catch reductions of 66.5 % in Glossina palpalis gambiensis and 90 % in G. tachinoides were observed in the intervention area. Trypanosome prevalence was significantly (p < 0.05) lower in the intervention area (2.3 %; 1.3-3.6 %) compared to the control area (17.3 %; 14.8-20.1 %). Albendazole treatment resulted in a faecal egg count reduction of 55.6 % and reduced trypanosome infection risk (2.9 times lower than in the placebo group) although not significantly (p > 0.05). Further studies are required before confirming the existence of albendazole resistant strongyles in the study area. Conclusion Integration of best-bet strategies in areas of multiple drug-resistance is expected to reduce trypanosome infection risk thus contributing to containment of trypanocidal drug resistance

  8. Non-specific cellular uptake of surface-functionalized quantum dots

    NASA Astrophysics Data System (ADS)

    Kelf, T. A.; Sreenivasan, V. K. A.; Sun, J.; Kim, E. J.; Goldys, E. M.; Zvyagin, A. V.

    2010-07-01

    We report a systematic empirical study of nanoparticle internalization into cells via non-specific pathways. The nanoparticles were comprised of commercial quantum dots (QDs) that were highly visible under a fluorescence confocal microscope. Surface-modified QDs with basic biologically significant moieties, e.g. carboxyl, amino, and streptavidin, were used, in combination with surface derivatization with polyethylene glycol (PEG) for a range of immortalized cell lines. Internalization rates were derived from image analysis and a detailed discussion about the effect of nanoparticle size, charge and surface groups is presented. We find that PEG derivatization dramatically suppresses the non-specific uptake while PEG-free carboxyl and amine functional groups promote QD internalization. These uptake variations displayed a remarkable consistency across different cell types. The reported results are important for experiments concerned with cellular uptake of surface-functionalized nanomaterials, both when non-specific internalization is undesirable and when it is intended for material to be internalized as efficiently as possible.

  9. Application of the probabilistic model BET_UNREST during a volcanic unrest simulation exercise in Dominica, Lesser Antilles

    NASA Astrophysics Data System (ADS)

    Constantinescu, Robert; Robertson, Richard; Lindsay, Jan M.; Tonini, Roberto; Sandri, Laura; Rouwet, Dmitri; Smith, Patrick; Stewart, Roderick

    2016-11-01

    We report on the first "real-time" application of the BET_UNREST (Bayesian Event Tree for Volcanic Unrest) probabilistic model, during a VUELCO Simulation Exercise carried out on the island of Dominica, Lesser Antilles, in May 2015. Dominica has a concentration of nine potentially active volcanic centers and frequent volcanic earthquake swarms at shallow depths, intense geothermal activity, and recent phreatic explosions (1997) indicate the region is still active. The exercise scenario was developed in secret by a team of scientists from The University of the West Indies (Trinidad and Tobago) and University of Auckland (New Zealand). The simulated unrest activity was provided to the exercise's Scientific Team in three "phases" through exercise injects comprising processed monitoring data. We applied the newly created BET_UNREST model through its software implementation PyBetUnrest, to estimate the probabilities of having (i) unrest of (ii) magmatic, hydrothermal or tectonic origin, which may or may not lead to (iii) an eruption. The probabilities obtained for each simulated phase raised controversy and intense deliberations among the members of the Scientific Team. The results were often considered to be "too high" and were not included in any of the reports presented to ODM (Office for Disaster Management) revealing interesting crisis communication challenges. We concluded that the PyBetUnrest application itself was successful and brought the tool one step closer to a full implementation. However, as with any newly proposed method, it needs more testing, and in order to be able to use it in the future, we make a series of recommendations for future applications.

  10. Bet hedging based cooperation can limit kin selection and form a basis for mutualism.

    PubMed

    Uitdehaag, Joost C M

    2011-07-07

    Mutualism is a mechanism of cooperation in which partners that differ help each other. As such, mutualism opposes mechanisms of kin selection and tag-based selection (for example the green beard mechanism), which are based on giving exclusive help to partners that are related or carry the same tag. In contrast to kin selection, which is a basis for parochialism and intergroup warfare, mutualism can therefore be regarded as a mechanism that drives peaceful coexistence between different groups and individuals. Here the competition between mutualism and kin (tag) selection is studied. In a model where kin selection and tag-based selection are dominant, mutualism is promoted by introducing environmental fluctuations. These fluctuations cause reduction in reproductive success by the mechanism of variance discount. The best strategy to counter variance discount is to share with agents who experience the most anticorrelated fluctuations, a strategy called bet hedging. In this way, bet hedging stimulates cooperation with the most unrelated partners, which is a basis for mutualism. Analytic results and simulations reveal that, if this effect is large enough, mutualistic strategies can dominate kin selective strategies. In addition, mutants of these mutualistic strategies that experience fluctuations that are more anticorrelated to their partner, can outcompete wild type, which can lead to the evolution of specialization. In this way, the evolutionary success of mutualistic strategies can be explained by bet hedging-based cooperation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. In situ and ex situ spectroscopic monitoring of biochar's surface functional groups

    USDA-ARS?s Scientific Manuscript database

    A number of studies described the higher heating temperature (HHT) as the primary pyrolysis parameter dictating the biochar property: surface functional group and fixed carbon contents, O/C, H/C ratios, and Brunauer-Emmett-Teller (BET) surface area. In order to produce desirable biochar properties ...

  12. Crystal Face Distributions and Surface Site Densities of Two Synthetic Goethites: Implications for Adsorption Capacities as a Function of Particle Size.

    PubMed

    Livi, Kenneth J T; Villalobos, Mario; Leary, Rowan; Varela, Maria; Barnard, Jon; Villacís-García, Milton; Zanella, Rodolfo; Goodridge, Anna; Midgley, Paul

    2017-09-12

    Two synthetic goethites of varying crystal size distributions were analyzed by BET, conventional TEM, cryo-TEM, atomic resolution STEM and HRTEM, and electron tomography in order to determine the effects of crystal size, shape, and atomic scale surface roughness on their adsorption capacities. The two samples were determined by BET to have very different site densities based on Cr VI adsorption experiments. Model specific surface areas generated from TEM observations showed that, based on size and shape, there should be little difference in their adsorption capacities. Electron tomography revealed that both samples crystallized with an asymmetric {101} tablet habit. STEM and HRTEM images showed a significant increase in atomic-scale surface roughness of the larger goethite. This difference in roughness was quantified based on measurements of relative abundances of crystal faces {101} and {201} for the two goethites, and a reactive surface site density was calculated for each goethite. Singly coordinated sites on face {210} are 2.5 more dense than on face {101}, and the larger goethite showed an average total of 36% {210} as compared to 14% for the smaller goethite. This difference explains the considerably larger adsorption capacitiy of the larger goethite vs the smaller sample and points toward the necessity of knowing the atomic scale surface structure in predicting mineral adsorption processes.

  13. Porous silicon structures with high surface area/specific pore size

    DOEpatents

    Northrup, M.A.; Yu, C.M.; Raley, N.F.

    1999-03-16

    Fabrication and use of porous silicon structures to increase surface area of heated reaction chambers, electrophoresis devices, and thermopneumatic sensor-actuators, chemical preconcentrates, and filtering or control flow devices. In particular, such high surface area or specific pore size porous silicon structures will be useful in significantly augmenting the adsorption, vaporization, desorption, condensation and flow of liquids and gases in applications that use such processes on a miniature scale. Examples that will benefit from a high surface area, porous silicon structure include sample preconcentrators that are designed to adsorb and subsequently desorb specific chemical species from a sample background; chemical reaction chambers with enhanced surface reaction rates; and sensor-actuator chamber devices with increased pressure for thermopneumatic actuation of integrated membranes. Examples that benefit from specific pore sized porous silicon are chemical/biological filters and thermally-activated flow devices with active or adjacent surfaces such as electrodes or heaters. 9 figs.

  14. Porous silicon structures with high surface area/specific pore size

    DOEpatents

    Northrup, M. Allen; Yu, Conrad M.; Raley, Norman F.

    1999-01-01

    Fabrication and use of porous silicon structures to increase surface area of heated reaction chambers, electrophoresis devices, and thermopneumatic sensor-actuators, chemical preconcentrates, and filtering or control flow devices. In particular, such high surface area or specific pore size porous silicon structures will be useful in significantly augmenting the adsorption, vaporization, desorption, condensation and flow of liquids and gasses in applications that use such processes on a miniature scale. Examples that will benefit from a high surface area, porous silicon structure include sample preconcentrators that are designed to adsorb and subsequently desorb specific chemical species from a sample background; chemical reaction chambers with enhanced surface reaction rates; and sensor-actuator chamber devices with increased pressure for thermopneumatic actuation of integrated membranes. Examples that benefit from specific pore sized porous silicon are chemical/biological filters and thermally-activated flow devices with active or adjacent surfaces such as electrodes or heaters.

  15. Detection analysis of surface hydroxyl active sites and simulation calculation of the surface dissociation constants of aqueous diatomite suspensions

    NASA Astrophysics Data System (ADS)

    Ma, Shu-Cui; Wang, Zhi-Gang; Zhang, Ji-Lin; Sun, De-Hui; Liu, Gui-Xia

    2015-02-01

    The surface properties of the diatomite were investigated using nitrogen adsorption/deadsorption isotherms, TG-DSC, FTIR, and XPS, and surface protonation-deprotonation behavior was determined by continuous acid-base potentiometric titration technique. The diatomite sample with porous honeycomb structure has a BET specific surface area of 10.21 m2/g and large numbers of surface hydroxyl functional groups (i.e. tbnd Si-OH, tbnd Fe-OH, and tbnd Al-OH). These surface hydroxyls can be protonated or deprotonated depending on the pH of the suspension. The experimental potentiometric data in two different ionic strength solutions (0.1 and 0.05 mol/L NaCl) were fitted using ProtoFit GUI V2.1 program by applying diffuse double layer model (DLM) with three amphoteric sites and minimizing the sum of squares between a dataset derivative function and a model derivative function. The optimized surface parameters (i.e. surface dissociation constants (log K1, log K2) and surface site concentrations (log C)) of the sample were obtained. Based on the optimized surface parameters, the surface species distribution was calculated using Program-free PHREEQC 3.1.2. Thus, this work reveals considerable new information about surface protonation-deprotonation processes and surface adsorptive behaviors of the diatomite, which helps us to effectively use the cheap and cheerful diatomite clay adsorbent.

  16. Estimation of the specific surface area for a porous carrier.

    PubMed

    Levstek, Meta; Plazl, Igor; Rouse, Joseph D

    2010-03-01

    In biofilm systems, treatment performance is primarily dependent upon the available biofilm growth surface area in the reactor. Specific surface area is thus a parameter that allows for making comparisons between different carrier technologies used for wastewater treatment. In this study, we estimated the effective surface area for a spherical, porous polyvinyl alcohol (PVA) gel carrier (Kuraray) that has previously demonstrated effectiveness for retention of autotrophic and heterotrophic biomass. This was accomplished by applying the GPS-X modeling tool (Hydromantis) to a comparative analysis of two moving-bed biofilm reactor (MBBR) systems. One system consisted of a lab-scale reactor that was fed synthetic wastewater under autotrophic conditions where only the nitrification process was studied. The other was a pre-denitrification pilot-scale plant that was fed real, primary-settled wastewater. Calibration of an MBBR process model for both systems indicated an effective specific surface area for PVA gel of 2500 m2/m3, versus a specific surface area of 1000 m2/m3 when only the outer surface of the gel beads is considered. In addition, the maximum specific growth rates for autotrophs and heterotrophs were estimated to be 1.2/day and 6.0/day, respectively.

  17. Efficacy of BET bromodomain inhibition in Kras-mutant non-small cell lung cancer

    PubMed Central

    Shimamura, Takeshi; Chen, Zhao; Soucheray, Margaret; Carretero, Julian; Kikuchi, Eiki; Tchaicha, Jeremy H.; Gao, Yandi; Cheng, Katherine A.; Cohoon, Travis J.; Qi, Jun; Akbay, Esra; Kimmelman, Alec C.; Kung, Andrew L.; Bradner, James E.; Wong, Kwok-Kin

    2013-01-01

    Purpose Amplification of MYC is one of the most common genetic alterations in lung cancer, contributing to a myriad of phenotypes associated with growth, invasion and drug resistance. Murine genetics has established both the centrality of somatic alterations of Kras in lung cancer, as well as the dependency of mutant Kras tumors on MYC function. Unfortunately, drug-like small-molecule inhibitors of KRAS and MYC have yet to be realized. The recent discovery, in hematologic malignancies, that BET bromodomain inhibition impairs MYC expression and MYC transcriptional function established the rationale of targeting KRAS-driven NSCLC with BET inhibition. Experimental Design We performed functional assays to evaluate the effects of JQ1 in genetically defined NSCLC cells lines harboring KRAS and/or LKB1 mutations. Furthermore, we evaluated JQ1 in transgenic mouse lung cancer models expressing mutant kras or concurrent mutant kras and lkb1. Effects of bromodomain inhibition on transcriptional pathways were explored and validated by expression analysis. Results While JQ1 is broadly active in NSCLC cells, activity of JQ1 in mutant KRAS NSCLC is abrogated by concurrent alteration or genetic knock-down of LKB1. In sensitive NSCLC models, JQ1 treatment results in the coordinate downregulation of the MYC-dependent transcriptional program. We found that JQ1 treatment produces significant tumor regression in mutant kras mice. As predicted, tumors from mutant kras and lkb1 mice did not respond to JQ1. Conclusion Bromodomain inhibition comprises a promising therapeutic strategy for KRAS mutant NSCLC with wild-type LKB1, via inhibition of MYC function. Clinical studies of BET bromodomain inhibitors in aggressive NSCLC will be actively pursued. PMID:24045185

  18. Sorption of N2 and EGME vapors on some soils, clays, and mineral oxides and determination of sample surface areas by use of sorption data

    USGS Publications Warehouse

    Chiou, C.T.; Rutherford, D.W.; Manes, M.

    1993-01-01

    Vapor sorption isotherms of ethylene glycol monoethyl ether (EGME) at room temperature and isotherms of N2 gas at liquid nitrogen temperature were determined for various soils and minerals. The N2 monolayer capacities [Qm (N2)] were calculated from the BET equation and used to determine the surface areas. To examine whether EGME is an appropriate adsorbate for determination of surface areas, the apparent EGME monolayer capacities [Qm (EGME)ap] were also obtained by use of the BET equation. For sand, aluminum oxide, kaolinite, hematite, and synthetic hydrous iron oxide, which are relatively free of organic impurity and expanding/solvating minerals, the Qm (EGME)ap values are in good conformity with the corresponding Qm (N2) values and would give surface areas consistent with BET (N2) values. For other samples (Woodburn soil, a natural hydrous iron oxide, illite, and montmorillonite), the Qm (EGME)ap values overestimate the Qm (N2) values from a moderate to a large extent, depending on the sample. A high-organic-content peat shows a very small BET (N2) surface area; the EGME/ peat isotherm is linear and does not yield a calculation of the surface area. Large discrepancies between results of the two methods for some samples are attributed to the high solubility of polar EGME in soil organic matter and/ or to the cation solvation of EGME with solvating clays. The agreement for other samples is illustrative of the consistency of the BET method when different adsorbates are used, so long as they do not exhibit bulk penetration and/or cation solvation. ?? 1993 American Chemical Society.

  19. Surface modification of lactose inhalation blends by moisture.

    PubMed

    Watling, C P; Elliott, J A; Scruton, C; Cameron, R E

    2010-05-31

    We present an investigation of the effects of relative humidity (RH) on lactose powders during storage, with the aims of determining the humidity conditions under which lactose inhalation blends are stable, and characterising the surface changes that occur as a result of water condensation. Lactose inhalation powders manufactured by milling and sieving were stored in environments of RH from 32% to 100% (at room temperature) and changes in surface properties were observed using BET nitrogen adsorption, environmental scanning electron microscopy and laser diffraction particle size analysis. We found that the specific surface area of all lactose powders decreased during storage, with the rate of decrease and final drop being larger at higher RH (ranging from a 62% decrease at 100% RH to a 34% decrease at 32% RH, at room temperature). The specific surface area decrease corresponded to a reduction in the volume of fine particles (<5 microm) in the blend. Two effects were found to contribute to the decrease in specific surface area: the smoothing of coarse particles, attributed to the surface fine particles undergoing deliquescence due to their enhanced solubility by the Kelvin effect (i.e. due to their greater curvature and consequently greater surface energy), and solid bridging between fine particles in agglomerates, such that loose fine particles disappeared from the powder blend, having bonded with coarser particles. These changes in particle properties resulting from moisture exposure are expected to influence the fine particle fraction of drug released from the powder blends, and the observation that lactose inhalation blends were unstable even at 32% RH could potentially be a concern for the pharmaceutical industry. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  20. The ΔfbpA attenuated candidate vaccine from Mycobacterium tuberculosis, H37Rv primes for a stronger T-bet dependent Th1 immunity in mice.

    PubMed

    Roche, Cherie M; Smith, Amanda; Lindsey, Devin R; Meher, Akshay; Schluns, Kimberly; Arora, Ashish; Armitige, Lisa Y; Jagannath, Chinnaswamy

    2011-12-01

    The ΔfbpA candidate vaccine derived from Mycobacterium tuberculosis (H37Rv) (Mtb) protects mice better than BCG against tuberculosis, and we investigated the hypothesis that ΔfbpA may induce a stronger Th1 immunity. Since T-bet transcription factor regulates Th1 immunity, mice infected with ΔfbpA, BCG vaccine and related mycobacteria were analyzed for T-bet positive T cells. Mouse dendritic cells (DCs) or macrophages were also pulsed with excretory-secreted antigens (ES; Antigen-85B, ESAT-6 and CFP10) and cocultured with T cells from immunized or naïve mice and tested for in vitro induction of T-bet and IFN-γ. In both models, ΔfbpA mutant induced a stronger response of T-bet(+)CD4 T cells, which correlated with an increased expansion of IFN-γ(+)CD4 T cells in vivo and in vitro. When DCs pulsed with ES antigens were allowed to stimulate T cells, ESAT-6 and CFP-10 failed to induce a recall expansion of T-bet(+)IFN-γ(+)CD4 T cells from BCG vaccinated mice. Thus, deletion of RD1 in BCG seems to reduce its ability to induce T-bet and induce stronger Th1 immunity. Finally, mice were vaccinated with ΔfbpA and BCG and challenged with virulent Mtb for evaluation of protection and T cell expansion. ΔfbpA vaccinated mice showed a rapid and stronger expansion of CD4(+)CXCR3(+) IFN-γ(+) T cells in the lungs of Mtb challenged mice, compared to those which had BCG vaccine. ΔfbpA immunized mice also showed a better decline of the Mtb bacterial counts of the lungs. Mtb derived ΔfbpA candidate vaccine therefore induces qualitatively better T-bet dependent Th1 immunity than BCG vaccine. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Structural and magnetic characterization of the "GASPAR" meteorite from Betéitiva, Boyacá, Colombia

    NASA Astrophysics Data System (ADS)

    Flor Torres, L. M.; Pérez Alcazar, G. A.

    2014-01-01

    A structural and magnetic characterization has been performed of a plate obtained from the "Gaspar" meteorite from the Otengá region of the Betéitiva municipality, Boyacá, Colombia. The sample was provided by Ingeominas (Colombian Geological Agency). After the studies the sample was classified as an octahedral iron meteorite, due the Fe and Ni concentrations and the Widmanstätten pattern which was observed on the surface of the sample. The plate shows a crack which divides the sample in two regions (side A and B, respectively). Both sides were studied using techniques like X-rays diffraction (XRD), Mössbauer spectrometry, optical microscopy, and scanning electronic microscopy (with EDAX). On both sides an iron Fe-Ni matrix (kamacite) was found; a large quantity of carbon in the form of graphite and in two types: nodular and laminar; and different preferential orientation in both sides of the sample. The studies permit to prove that Gaspar is a fragment of the registered Santa Rosa de Viterbo meteorite.

  2. Bet Anywhere, Anytime: An Analysis of Internet Sports Bettors' Responses to Gambling Promotions During Sports Broadcasts by Problem Gambling Severity.

    PubMed

    Hing, Nerilee; Russell, Alex Myles Thomas; Lamont, Matthew; Vitartas, Peter

    2017-12-01

    Promotions for online sports betting during televised sports broadcasts are regularly viewed by millions of Australians, raising concerns about their impacts on vulnerable groups including at-risk and problem gamblers. This study examined whether responses to these promotions varied with problem gambling severity amongst 455 Australian Internet sports bettors participating in an online survey. Results indicated that young male Internet sports bettors are especially vulnerable to gambling problems, particularly if they hold positive attitudes to gambling sponsors who embed promotions into sports broadcasts and to the promotional techniques they use and this heightens the risk that alluring messages contribute to excessive gambling. As problem gambling severity increased, so too did recognition that these promotions have impacted negatively on their sports betting behaviour. Because a plethora of sports betting brands and promotions are now heavily integrated into sports coverage, social marketing efforts are needed to offset their persuasive appeal and counter the positive attitudes towards them that appear linked to excessive gambling amongst Internet sports bettors.

  3. Specific surface area of a crushed welded tuff before and after aqueous dissolution

    USGS Publications Warehouse

    Reddy, M.M.; Claassen, H.C.

    1994-01-01

    Specific surface areas were measured for several reference minerals (anorthoclase, labradorite and augite), welded tuff and stream sediments from Snowshoe Mountain, near Creede, Colorado. Crushed and sieved tuff had an unexpectedly small variation in specific surface area over a range of size fractions. Replicate surface area measurements of the largest and smallest tuff particle size fractions examined (1-0.3 mm and <0.212 mm) were 2.3 ?? 0.2 m2/g for each size fraction. Reference minerals prepared in the same way as the tuff had smaller specific surface areas than that of the tuff of the same size fraction. Higher than expected tuff specific surface areas appear to be due to porous matrix. Tuff, reacted in solutions with pH values from 2 to 6, had little change in specific surface area in comparison with unreacted tuff. Tuff, reacted with solutions having high acid concentrations (0.1 M hydrochloric acid or sulfuric-hydrofluoric acid), exhibited a marked increase in specific surface area compared to unreacted tuff. ?? 1994.

  4. Properties of Basil and Lavender Essential Oils Adsorbed on the Surface of Hydroxyapatite.

    PubMed

    Predoi, Daniela; Groza, Andreea; Iconaru, Simona Liliana; Predoi, Gabriel; Barbuceanu, Florica; Guegan, Regis; Motelica-Heino, Mikael Stefan; Cimpeanu, Carmen

    2018-04-24

    The research conducted in this study presented for the first time results of physico-chemical properties and in vitro antimicrobial activity of hydroxyapatite plant essential oil against Gram-positive bacteria (methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus 0364) and Gram-negative bacteria ( Escherichia coli ATCC 25922). The samples were studied by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy to determine the morphology and structure of the nanocomposites of hydroxyapatite coated with basil (HAp-B) and lavender (HAp-L) essential oils (EOs). The values of the BET specific surface area (S BET ), total pore volume (V P ) and pore size (D P ) were determined. The results for the physico-chemical properties of HAp-L and HAp-B revealed that lavender EOs were well adsorbed on the surface of hydroxyapatite, whereas basil EOs showed a poor adsorption on the surface of hydroxyapatite. We found that the lavender EOs hydroxyapatite (HAp-L) exhibited a very good inhibitory growth activity. The value of the minimum inhibitory concentration (MIC) related to growth bacteria was 0.039 mg/mL for MRSA, 0.02 mg/mL for S. aureus and 0.039 mg/mL E. coli ATCC 25922. The basil EO hydroxyapatite (HAp-B) showed poor inhibition of bacterial cell growth. The MIC value was 0.625 mg/mL for the HAp-B sample in the presence of the MRSA bacteria, 0.313 mg/mL in the presence of S. aureus and 0.078 mg/mL for E. coli ATCC 25922.

  5. Subjective experience guides betting decisions beyond accuracy: evidence from a metamemory illusion.

    PubMed

    Hembacher, Emily; Ghetti, Simona

    2017-05-01

    The goal of this research was to test whether subjective memory experiences drive accuracy regulation decisions above and beyond objective memory indices. In four experiments (n = 115) subjective recollection (i.e., reporting "Remember" in the Remember-Know task) was dissociated from memory accuracy by manipulating retrieval during a two-alternative forced-choice recognition task: in the Match condition the distracter was a novel exemplar of the target (e.g., a studied and an unstudied toaster) and in the Non-match condition the distracter was a novel exemplar of another studied but untested item (e.g., a studied toaster and an unstudied birdhouse). Participants were more accurate on Match trials, but reported subjective recollection more frequently on Non-match trials. Critically, participants also bet more often on Non-match trials to the detriment of their score (Experiment 1). This pattern persisted when participants were additionally required to retrieve details about items (Experiment 2) and when confidence assessments were collected (Experiment 3). Finally, participants bet more on Non-match trials even when subjective judgments were not elicited, suggesting that the decision process does not require reporting on subjective experience (Experiment 4). These results indicate that subjective memory experiences guide decision-making independent of objective accuracy and thus are critical to accuracy regulation.

  6. Bet-hedging in bacteriocin producing Escherichia coli populations: the single cell perspective

    NASA Astrophysics Data System (ADS)

    Bayramoglu, Bihter; Toubiana, David; van Vliet, Simon; Inglis, R. Fredrik; Shnerb, Nadav; Gillor, Osnat

    2017-02-01

    Production of public goods in biological systems is often a collaborative effort that may be detrimental to the producers. It is therefore sustainable only if a small fraction of the population shoulders the cost while the majority reap the benefits. We modelled this scenario using Escherichia coli populations producing colicins, an antibiotic that kills producer cells’ close relatives. Colicin expression is a costly trait, and it has been proposed that only a small fraction of the population actively expresses the antibiotic. Colicinogenic populations were followed at the single-cell level using time-lapse microscopy, and showed two distinct, albeit dynamic, subpopulations: the majority silenced colicin expression, while a small fraction of elongated, slow-growing cells formed colicin-expressing hotspots, placing a significant burden on expressers. Moreover, monitoring lineages of individual colicinogenic cells showed stochastic switching between expressers and non-expressers. Hence, colicin expressers may be engaged in risk-reducing strategies—or bet-hedging—as they balance the cost of colicin production with the need to repel competitors. To test the bet-hedging strategy in colicin-mediated interactions, competitions between colicin-sensitive and producer cells were simulated using a numerical model, demonstrating a finely balanced expression range that is essential to sustaining the colicinogenic population.

  7. A Sure Bet: Business & Education Together. A Handbook for Chamber of Commerce Education Committees.

    ERIC Educational Resources Information Center

    Abbott, Carol Iddins; Harper, H. James, Ed.

    Project BET (Business and Education Together) was initiated by the California Chamber of Commerce in January 1984 to assist local chambers of commerce in developing long-term school-business partnerships. This handbook, based on work with six pilot chambers of commerce, offers a step-by-step process guide to school-business partnerships, along…

  8. Determining surface areas of marine alga cells by acid-base titration method.

    PubMed

    Wang, X; Ma, Y; Su, Y

    1997-09-01

    A new method for determining the surface area of living marine alga cells was described. The method uses acid-base titration to measure the surface acid/base amount on the surface of alga cells and uses the BET (Brunauer, Emmett, and Teller) equation to estimate the maximum surface acid/base amount, assuming that hydrous cell walls have carbohydrates or other structural compounds which can behave like surface Brönsted acid-base sites due to coordination of environmental H2O molecules. The method was applied to 18 diverse alga species (including 7 diatoms, 2 flagellates, 8 green algae and 1 red alga) maintained in seawater cultures. For the species examined, the surface areas of individual cells ranged from 2.8 x 10(-8) m2 for Nannochloropsis oculata to 690 x 10(-8) m2 for Dunaliella viridis, specific surface areas from 1,030 m2.g-1 for Dunaliella salina to 28,900 m2.g-1 for Pyramidomonas sp. Measurement accuracy was 15.2%. Preliminary studies show that the method may be more promising and accurate than light/electron microscopic measurements for coarse estimation of the surface area of living algae.

  9. Analysis of the predictive qualities of betting odds and FIFA World Ranking: evidence from the 2006, 2010 and 2014 Football World Cups.

    PubMed

    Wunderlich, Fabian; Memmert, Daniel

    2016-12-01

    The present study aims to investigate the ability of a new framework enabling to derive more detailed model-based predictions from ranking systems. These were compared to predictions from the bet market including data from the World Cups 2006, 2010, and 2014. The results revealed that the FIFA World Ranking has essentially improved its predictive qualities compared to the bet market since the mode of calculation was changed in 2006. While both predictors were useful to obtain accurate predictions in general, the world ranking was able to outperform the bet market significantly for the World Cup 2014 and when the data from the World Cups 2010 and 2014 were pooled. Our new framework can be extended in future research to more detailed prediction tasks (i.e., predicting the final scores of a match or the tournament progress of a team).

  10. Specific surface area as a maturity index of lunar fines

    NASA Technical Reports Server (NTRS)

    Gammage, R. B.; Holmes, H. F.

    1975-01-01

    Mature surface fines have an equilibrium specific surface area of about 0.6 sq m/g the equivalent mean particle size being about 3 microns. The adsorption behavior of inert gases (reversible isotherms) indicates that the particles are also nonporous in the size range of pores from 10 to 3000 A. Apparently, in mature soils there is a balance in the forces which cause fining, attrition, pore filling, and growth of lunar dust grains. Immature, lightly irradiated soils usually have coarser grains which reduce in size as aging proceeds. The specific surface area, determined by nitrogen or krypton sorption at 77 K, is a valuable index of soil maturity.

  11. Not putting all their eggs in one basket: bet-hedging despite extraordinary annual reproductive output of desert tortoises

    USGS Publications Warehouse

    Lovich, Jeffrey E.; Ennen, Joshua R.; Yackulic, Charles B.; Meyer-Wilkins, Kathie; Agha, Mickey; Loughran, Caleb L.; Bjurlin, Curtis; Austin, Meaghan; Madrak, Sheila V.

    2015-01-01

    Bet-hedging theory makes the counter-intuitive prediction that, if juvenile survival is low and unpredictable, organisms should consistently reduce short-term reproductive output to minimize the risk of reproductive failure in the long-term. We investigated the long-term reproductive output of an Agassiz's desert tortoise (Gopherus agassizii) population and conformance to a bet-hedging strategy of reproduction in an unpredictable but comparatively productive environment. Most females reproduced every year, even during periods of low precipitation and poor germination of food plants, and the mean percentage of reproducing females did not differ significantly on an annual basis. Although mean annual egg production (clutch size × clutch frequency) differed significantly among years, mean clutch size and mean clutch frequency remained relatively constant. During an El Niño year, mean annual egg production and mean annual clutch frequency were the highest ever reported for this species. Annual egg production was positively influenced by maternal body size but clutch size and clutch frequency were not. Our long-term results confirm earlier conclusions based on short-term research that desert tortoises have a bet-hedging strategy of producing small clutches almost every year. The risk of long-term reproductive failure is minimized in unpredictable environments, both through time by annually producing multiple small clutches over a long reproductive lifespan, even in years of low resource availability, and through space by depositing multiple annual clutches in different locations. The extraordinary annual reproductive output of this population appears to be the result of a typically high but unpredictable biomass of annual food plants at the site relative to tortoise habitat in dryer regions. Under the comparatively productive but unpredictable conditions, tortoises conform to predictions of a bet-hedging strategy of reproduction with relatively small but consistent

  12. Functional cell-surface display of a lipase-specific chaperone.

    PubMed

    Wilhelm, Susanne; Rosenau, Frank; Becker, Stefan; Buest, Sebastian; Hausmann, Sascha; Kolmar, Harald; Jaeger, Karl-Erich

    2007-01-02

    Lipases are important enzymes in biotechnology. Extracellular bacterial lipases from Pseudomonads and related species require the assistance of specific chaperones, designated "Lif" proteins (lipase specific foldases). Lifs, a unique family of steric chaperones, are anchored to the periplasmic side of the inner membrane where they convert lipases into their active conformation. We have previously shown that the autotransporter protein EstA from P. aeruginosa can be used to direct a variety of proteins to the cell surface of Escherichia coli. Here we demonstrate for the first time the functional cell-surface display of the Lif chaperone and FACS (fluorescence-activated cell sorting)-based analysis of bacterial cells that carried foldase-lipase complexes. The model Lif protein, LipH from P. aeruginosa, was displayed at the surface of E. coli cells. Surface exposed LipH was functional and efficiently refolded chemically denatured lipase. The foldase autodisplay system reported here can be used for a variety of applications including the ultrahigh-throughput screening of large libraries of foldase variants generated by directed evolution.

  13. Poker, Sports Betting, and Less Popular Alternatives: Status, Friendship Networks, and Male Adolescent Gambling

    ERIC Educational Resources Information Center

    DiCicco-Bloom, Benjamin; Romer, Daniel

    2012-01-01

    The authors argue that the recent increase in poker play among adolescent males in the United States was primarily attributable to high-status male youth who are more able to organize "informal" gambling games (e.g., poker and sports betting) than are low-status male youth who are left to gamble on "formal" games (e.g., lotteries and slot…

  14. Surface-modified gold nanorods for specific cell targeting

    NASA Astrophysics Data System (ADS)

    Wang, Chan-Ung; Arai, Yoshie; Kim, Insun; Jang, Wonhee; Lee, Seonghyun; Hafner, Jason H.; Jeoung, Eunhee; Jung, Deokho; Kwon, Youngeun

    2012-05-01

    Gold nanoparticles (GNPs) have unique properties that make them highly attractive materials for developing functional reagents for various biomedical applications including photothermal therapy, targeted drug delivery, and molecular imaging. For in vivo applications, GNPs need to be prepared with very little or negligible cytotoxicitiy. Most GNPs are, however, prepared using growth-directing surfactants such as cetyl trimethylammonium bromide (CTAB), which are known to have considerable cytotoxicity. In this paper, we describe an approach to remove CTAB to a non-toxic concentration. We optimized the conditions for surface modification with methoxypolyethylene glycol thiol (mPEG), which replaced CTAB and formed a protective layer on the surface of gold nanorods (GNRs). The cytotoxicities of pristine and surface-modified GNRs were measured in primary human umbilical vein endothelial cells and human cell lines derived from hepatic carcinoma cells, embryonic kidney cells, and thyroid papillary carcinoma cells. Cytotoxicity assays revealed that treating cells with GNRs did not significantly affect cell viability except for thyroid papillary carcinoma cells. Thyroid cancer cells were more susceptible to residual CTAB, so CTAB had to be further removed by dialysis in order to use GNRs for thyroid cell targeting. PEGylated GNRs are further modified to present monoclonal antibodies that recognize a specific surface marker, Na-I symporter, for thyroid cells. Antibody-conjugated GNRs specifically targeted human thyroid cells in vitro.

  15. Response mechanism for surface acoustic wave gas sensors based on surface-adsorption.

    PubMed

    Liu, Jiansheng; Lu, Yanyan

    2014-04-16

    A theoretical model is established to describe the response mechanism of surface acoustic wave (SAW) gas sensors based on physical adsorption on the detector surface. Wohljent's method is utilized to describe the relationship of sensor output (frequency shift of SAW oscillator) and the mass loaded on the detector surface. The Brunauer-Emmett-Teller (BET) formula and its improved form are introduced to depict the adsorption behavior of gas on the detector surface. By combining the two methods, we obtain a theoretical model for the response mechanism of SAW gas sensors. By using a commercial SAW gas chromatography (GC) analyzer, an experiment is performed to measure the frequency shifts caused by different concentration of dimethyl methylphosphonate (DMMP). The parameters in the model are given by fitting the experimental results and the theoretical curve agrees well with the experimental data.

  16. Response Mechanism for Surface Acoustic Wave Gas Sensors Based on Surface-Adsorption

    PubMed Central

    Liu, Jiansheng; Lu, Yanyan

    2014-01-01

    A theoretical model is established to describe the response mechanism of surface acoustic wave (SAW) gas sensors based on physical adsorption on the detector surface. Wohljent's method is utilized to describe the relationship of sensor output (frequency shift of SAW oscillator) and the mass loaded on the detector surface. The Brunauer-Emmett-Teller (BET) formula and its improved form are introduced to depict the adsorption behavior of gas on the detector surface. By combining the two methods, we obtain a theoretical model for the response mechanism of SAW gas sensors. By using a commercial SAW gas chromatography (GC) analyzer, an experiment is performed to measure the frequency shifts caused by different concentration of dimethyl methylphosphonate (DMMP). The parameters in the model are given by fitting the experimental results and the theoretical curve agrees well with the experimental data. PMID:24743157

  17. Adsorbed Natural Gas Storage in Optimized High Surface Area Microporous Carbon

    NASA Astrophysics Data System (ADS)

    Romanos, Jimmy; Rash, Tyler; Nordwald, Erik; Shocklee, Joshua Shawn; Wexler, Carlos; Pfeifer, Peter

    2011-03-01

    Adsorbed natural gas (ANG) is an attractive alternative technology to compressed natural gas (CNG) or liquefied natural gas (LNG) for the efficient storage of natural gas, in particular for vehicular applications. In adsorbants engineered to have pores of a few molecular diameters, a strong van der Walls force allows reversible physisorption of methane at low pressures and room temperature. Activated carbons were optimized for storage by varying KOH:C ratio and activation temperature. We also consider the effect of mechanical compression of powders to further enhance the volumetric storage capacity. We will present standard porous material characterization (BET surface area and pore-size distribution from subcritical N2 adsorption) and methane isotherms up to 250 bar at 293K. At sufficiently high pressure, specific surface area, methane binding energy and film density can be extracted from supercritical methane adsorption isotherms. Research supported by the California Energy Commission (500-08-022).

  18. The C-terminal domain of the betaine carrier BetP of Corynebacterium glutamicum is directly involved in sensing K+ as an osmotic stimulus.

    PubMed

    Schiller, Dirk; Rübenhagen, René; Krämer, Reinhard; Morbach, Susanne

    2004-05-18

    The glycine betaine carrier BetP of Corynebacterium glutamicum was recently shown to function both as an osmosensor and as an osmoregulator in proteoliposomes by sensing changes in the internal K(+) concentration as a measure of hyperosmotic stress. In vivo analysis of mutants carrying deletions at the C-terminal extension of BetP indicated that this domain participates in osmostress-dependent activity regulation. To address the question, whether a putative K(+) sensor is located within the C-terminal domain, several mutants with truncations in this domain were purified and reconstituted in proteoliposomes of Escherichia coli phospholipids, since this in vitro system allowed variation of the K(+) concentration at the lumenal side. Truncation of 12 amino acids led to a partly deregulated BetP in terms of osmoregulation; however, K(+) sensitivity was not impaired in this mutant. The deletion of 25 amino acid residues at the C-terminal end of BetP led to both deregulation of the carrier activity, i.e., high activity independent of external osmolality, and loss of K(+)-dependent transport stimulation, indicating that this region of the C-terminal domain is necessary for K(+) sensing and/or K(+)-dependent carrier activation. Immunological and proteolysis analyses showed that BetP and its recombinant forms were reconstituted in a right-side-out orientation, i.e., the C-terminal domain faces the lumen of the proteoliposomes and is thus able to detect the K(+) signal at the inside. This is the first experimental demonstration of a direct connection between an osmotic stimulus, i.e., the change in internal K(+), and a putative sensor domain.

  19. Regulation of the glucocorticoid receptor via a BET-dependent enhancer drives antiandrogen resistance in prostate cancer.

    PubMed

    Shah, Neel; Wang, Ping; Wongvipat, John; Karthaus, Wouter R; Abida, Wassim; Armenia, Joshua; Rockowitz, Shira; Drier, Yotam; Bernstein, Bradley E; Long, Henry W; Freedman, Matthew L; Arora, Vivek K; Zheng, Deyou; Sawyers, Charles L

    2017-09-11

    In prostate cancer, resistance to the antiandrogen enzalutamide (Enz) can occur through bypass of androgen receptor (AR) blockade by the glucocorticoid receptor (GR). In contrast to fixed genomic alterations, here we show that GR-mediated antiandrogen resistance is adaptive and reversible due to regulation of GR expression by a tissue-specific enhancer. GR expression is silenced in prostate cancer by a combination of AR binding and EZH2-mediated repression at the GR locus, but is restored in advanced prostate cancers upon reversion of both repressive signals. Remarkably, BET bromodomain inhibition resensitizes drug-resistant tumors to Enz by selectively impairing the GR signaling axis via this enhancer. In addition to revealing an underlying molecular mechanism of GR-driven drug resistance, these data suggest that inhibitors of broadly active chromatin-readers could have utility in nuanced clinical contexts of acquired drug resistance with a more favorable therapeutic index.

  20. Revision and further validation of surface-performance graded specification for surface treatment binders.

    DOT National Transportation Integrated Search

    2012-12-01

    The design and selection of surface treatment binders in service is currently based on specifications that include tests of emulsion residues or hot-applied asphalt cements at standard temperatures that do not cover the entire range of in service tem...

  1. BET bromodomain inhibition enhances T cell persistence and function in adoptive immunotherapy models.

    PubMed

    Kagoya, Yuki; Nakatsugawa, Munehide; Yamashita, Yuki; Ochi, Toshiki; Guo, Tingxi; Anczurowski, Mark; Saso, Kayoko; Butler, Marcus O; Arrowsmith, Cheryl H; Hirano, Naoto

    2016-09-01

    Adoptive immunotherapy is a potentially curative therapeutic approach for patients with advanced cancer. However, the in vitro expansion of antitumor T cells prior to infusion inevitably incurs differentiation towards effector T cells and impairs persistence following adoptive transfer. Epigenetic profiles regulate gene expression of key transcription factors over the course of immune cell differentiation, proliferation, and function. Using comprehensive screening of chemical probes with defined epigenetic targets, we found that JQ1, an inhibitor of bromodomain and extra-terminal motif (BET) proteins, maintained CD8+ T cells with functional properties of stem cell-like and central memory T cells. Mechanistically, the BET protein BRD4 directly regulated expression of the transcription factor BATF in CD8+ T cells, which was associated with differentiation of T cells into an effector memory phenotype. JQ1-treated T cells showed enhanced persistence and antitumor effects in murine T cell receptor and chimeric antigen receptor gene therapy models. Furthermore, we found that histone acetyltransferase p300 supported the recruitment of BRD4 to the BATF promoter region, and p300 inhibition similarly augmented antitumor effects of the adoptively transferred T cells. These results demonstrate that targeting the BRD4-p300 signaling cascade supports the generation of superior antitumor T cell grafts for adoptive immunotherapy.

  2. BET inhibitors induce apoptosis through a MYC independent mechanism and synergise with CDK inhibitors to kill osteosarcoma cells

    PubMed Central

    Baker, Emma K; Taylor, Scott; Gupte, Ankita; Sharp, Phillip P; Walia, Mannu; Walsh, Nicole C; Zannettino, Andrew CW; Chalk, Alistair M; Burns, Christopher J; Walkley, Carl R

    2015-01-01

    Osteosarcoma (OS) survival rates have plateaued in part due to a lack of new therapeutic options. Here we demonstrate that bromodomain inhibitors (BETi), JQ1, I-BET151, I-BET762, exert potent anti-tumour activity against primary and established OS cell lines, mediated by inhibition of BRD4. Strikingly, unlike previous observations in long-term established human OS cell lines, the antiproliferative activity of JQ1 in primary OS cells was driven by the induction of apoptosis, not cell cycle arrest. In further contrast, JQ1 activity in OS was mediated independently of MYC downregulation. We identified that JQ1 suppresses the transcription factor FOSL1 by displacement of BRD4 from its locus. Loss of FOSL1 phenocopied the antiproliferative effects of JQ1, identifying FOSL1 suppression as a potential novel therapeutic approach for OS. As a monotherapy JQ1 demonstrated significant anti-tumour activity in vivo in an OS graft model. Further, combinatorial treatment approaches showed that JQ1 increased the sensitivity of OS cells to doxorubicin and induced potent synergistic activity when rationally combined with CDK inhibitors. The greater level of activity achieved with the combination of BETi with CDK inhibitors demonstrates the efficacy of this combination therapy. Taken together, our studies show that BET inhibitors are a promising new therapeutic for OS. PMID:25944566

  3. Increased numbers of preexisting memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells.

    PubMed

    Joshi, Nikhil S; Cui, Weiguo; Dominguez, Claudia X; Chen, Jonathan H; Hand, Timothy W; Kaech, Susan M

    2011-10-15

    Memory CD8 T cells acquire effector memory cell properties after reinfection and may reach terminally differentiated, senescent states ("Hayflick limit") after multiple infections. The signals controlling this process are not well understood, but we found that the degree of secondary effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and preexisting memory CD8 T cell number (i.e., primary memory CD8 T cell precursor frequency) present during secondary infection. Compared with naive cells, memory CD8 T cells were predisposed toward terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of Ag. TE cell formation after secondary (2°) or tertiary infections was dependent on increased T-bet expression because T-bet(+/-) cells were resistant to these phenotypic changes. Larger numbers of preexisting memory CD8 T cells limited the duration of 2° infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2° TE CD8 T cells that formed. Together, these data show that over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with Ag or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by preexisting memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies.

  4. Nature of immobilization surface affects antibody specificity to placental alkaline phosphatase.

    PubMed

    Kumar, Mukesh; Khan, Imran; Sinha, Subrata

    2015-01-01

    Retention of native conformation of immobilized protein is essential for various applications including selection and detection of specific recombinant antibodies (scFvs). Placental alkaline phosphatase (PAP), an onco-fetal antigen expressed on the surface of several tumors, was immobilized on supermagnetic particles for selection of recombinant antibodies from a human phage display antibody library. The isolated antibodies were found to be cross-reactive to either of the isozymes of alkaline phosphatase, i.e., bone alkaline phosphatase (BAP) or intestinal alkaline phosphatase (IAP) and could not be used for tumor targeting. A specific anti-PAP monoclonal antibody H17E2 was tested for retention of specificity under these conditions. Binding of the antibody to magnetic beads conjugated IAP and BAP along with PAP and the ability of the two isozymes to inhibit its binding to PAP depicted the loss of isozyme specificity of the antibody. However, the antibody retained its specificity to PAP immobilized on polyvinyl chloride (PVC) surface. Enzyme activity was observed on both surfaces. This demonstrates that nature of immobilization may affect antigen-antibody binding in subtle ways, resulting in alteration of conformation of the epitopes. This may have consequences for determining the specificity of antibody binding for proteins that share a high degree of homology.

  5. Hierarchical mesosilicalite nanoformulation integrated with cisplatin exhibits target-specific efficient anticancer activity

    NASA Astrophysics Data System (ADS)

    Jermy, B. Rabindran; Acharya, Sadananda; Ravinayagam, Vijaya; Alghamdi, Hajer Saleh; Akhtar, Sultan; Basuwaidan, Rehab S.

    2018-04-01

    Hierarchically structured zeolitic ZSM-5 and meso MCM-41 interlinked domain had an impeccable use as catalysis in many applications. The aim of the study was to develop a new drug delivery nanoformulation, specifically, cisplatin/mesosilicalite using top-down approach for cancer therapy. Hierarchical mesosilicalite with variable porosity was synthesized using alkaline molar solution (0.2 and 0.7 M NaOH) and was loaded with cisplatin through equilibrium adsorption technique. Physico-chemical properties of the nanoformulation (IAUM-56—Imam Abdulrahman Bin Faisal University Mesosilicalite-56) were characterized using X-ray diffraction, surface area analysis (BET), Fourier transformed infrared spectroscopy (FT-IR), diffuse reflectance UV-Vis spectroscopy, and transmission electron microscopy. Drug release study and anticancer activity were assayed on HeLa and MCF7 cancer cells using MTT assay. X-ray diffraction pattern showed interrelated meso- and microphases, while BET analysis revealed considerable mesoporosity formation with a remodulation of isotherm hysteresis indicating the presence of hierarchical pores. FT-IR showed the presence of nanozeolitic subunits into mesostructure with a band at about 550 cm-1. IAUM-56 demonstrated high cytotoxic activity against HeLa cancer cells with an LC50 of 0.02 mg/ml, MCF7 cancer cells with an LC50 of 0.05 mg/ml, and less toxic to normal fibroblast cells with an LC50 of approximately ten times higher at 0.5 mg/ml. Overall, IAUM-56 showed a high rate of sustained release of cisplatin imparting target specific cytotoxic effect against tumor cells with at least tenfold lower toxicity on normal fibroblast cells. Our nanoformulation has the potential use in cancer therapy as a targeted drug delivery system.

  6. NMR Structure of Francisella tularensis Virulence Determinant Reveals Structural Homology to Bet v1 Allergen Proteins.

    PubMed

    Zook, James; Mo, Gina; Sisco, Nicholas J; Craciunescu, Felicia M; Hansen, Debra T; Baravati, Bobby; Cherry, Brian R; Sykes, Kathryn; Wachter, Rebekka; Van Horn, Wade D; Fromme, Petra

    2015-06-02

    Tularemia is a potentially fatal bacterial infection caused by Francisella tularensis, and is endemic to North America and many parts of northern Europe and Asia. The outer membrane lipoprotein, Flpp3, has been identified as a virulence determinant as well as a potential subunit template for vaccine development. Here we present the first structure for the soluble domain of Flpp3 from the highly infectious Type A SCHU S4 strain, derived through high-resolution solution nuclear magnetic resonance (NMR) spectroscopy; the first structure of a lipoprotein from the genus Francisella. The Flpp3 structure demonstrates a globular protein with an electrostatically polarized surface containing an internal cavity-a putative binding site based on the structurally homologous Bet v1 protein family of allergens. NMR-based relaxation studies suggest loop regions that potentially modulate access to the internal cavity. The Flpp3 structure may add to the understanding of F. tularensis virulence and contribute to the development of effective vaccines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Influence of specific surface area on coal dust explosibility using the 20-L chamber.

    PubMed

    Zlochower, Isaac A; Sapko, Michael J; Perera, Inoka E; Brown, Connor B; Harris, Marcia L; Rayyan, Naseem S

    2018-07-01

    The relationship between the explosion inerting effectiveness of rock dusts on coal dusts, as a function of the specific surface area (cm 2 /g) of each component is examined through the use of 20-L explosion chamber testing. More specifically, a linear relationship is demonstrated for the rock dust to coal dust (or incombustible to combustible) content of such inerted mixtures with the specific surface area of the coal and the inverse of that area of the rock dust. Hence, the inerting effectiveness, defined as above, is more generally linearly dependent on the ratio of the two surface areas. The focus on specific surface areas, particularly of the rock dust, provide supporting data for minimum surface area requirements in addition to the 70% less than 200 mesh requirement specified in 30 CFR 75.2.

  8. Impact of Exposure to Pressure of 50 MPa on the Specific Surface Area of Clay

    NASA Astrophysics Data System (ADS)

    Koszela-Marek, Ewa

    2017-12-01

    The paper presents results of laboratory tests conducted to determine the impact of pressure of 50 MPa on specific surface area of clay. These tests were carried out in an original, high-pressure test stand. The specific surface area of clay extracted directly from an open pit mine was compared with the specific surface area of the same clay subjected to the pressure of 50 MPa in a high-pressure chamber. The study found that the specific surface area of the clay subjected to the pressure of 50 MPa increased distinctly by over 35 %. The increase in specific surface can be a result of changes in the microstructure of clay particles and microstructural alteration in the soil skeleton, caused by the pressure.

  9. Properties that influence the specific surface areas of carbon nanotubes and nanofibers.

    PubMed

    Birch, M Eileen; Ruda-Eberenz, Toni A; Chai, Ming; Andrews, Ronnee; Hatfield, Randal L

    2013-11-01

    Commercially available carbon nanotubes and nanofibers were analyzed to examine possible relationships between their Brunauer-Emmett-Teller specific surface areas (SSAs) and their physical and chemical properties. Properties found to influence surface area were number of walls/diameter, impurities, and surface functionalization with hydroxyl and carboxyl groups. Characterization by electron microscopy, energy-dispersive X-ray spectrometry, thermogravimetric analysis, and elemental analysis indicates that SSA can provide insight on carbon nanomaterials properties, which can differ vastly depending on synthesis parameters and post-production treatments. In this study, how different properties may influence surface area is discussed. The materials examined have a wide range of surface areas. The measured surface areas differed from product specifications, to varying degrees, and between similar products. Findings emphasize the multiple factors that influence surface area and mark its utility in carbon nanomaterial characterization, a prerequisite to understanding their potential applications and toxicities. Implications for occupational monitoring are discussed.

  10. Adsorption of water vapour and the specific surface area of arctic zone soils (Spitsbergen)

    NASA Astrophysics Data System (ADS)

    Cieśla, Jolanta; Sokołowska, Zofia; Witkowska-Walczak, Barbara; Skic, Kamil

    2018-01-01

    Water vapour/nitrogen adsorption were investigated and calculated the specific surface areas of arctic-zone soil samples (Turbic Cryosols) originating from different micro-relief forms (mud boils, cell forms and sorted circles) and from different depths. For the characterisation of the isotherms obtained for arctic soils, the Brunauer-Emmet-Teller model was then compared with the two other models (Aranovich-Donohue and Guggenheim-Anderson-de Boer) which were developed from Brunauer-Emmet-Teller. Specific surface area was calculated using the Brunauer-Emmet-Teller model at p p0-1 range of 0.05-0.35 for the water vapour desorption and nitrogen adsorption isotherms. The values of total specific surface area were the highest in Cryosols on mud boils, lower on cell forms, and the lowest on sorted circles. Such tendency was observed for the results obtained by both the water vapour and nitrogen adsorption. The differences in the values of specific surface area at two investigated layers were small. High determination coefficients were obtained for relationships between the specific surface areas and contents of clay and silt fraction in Cryosols. No statistically significant correlation between the total carbon amount and the values of specific surface area in Cryosols has been found.

  11. Surface Dynamics of Unipolar Arcing

    DTIC Science & Technology

    1989-12-01

    slioising bulk copper deposition. (6.4X)( i10 ) Figure 20. Copper deposition on a steel surface shoiing a cor relation bet’seeni greater pitting...pit’s depth and its width. 1. Arc damage - a heating phenomenon To study the effect of the same laser shot. and the same unipolar arc. on two...between pit depth and diameter for pitting on the copper films. This conclusion comes from the fact that in many cases pits with relatively smaller

  12. Photoresponsive peptide azobenzene conjugates that specifically interact with platinum surfaces

    NASA Astrophysics Data System (ADS)

    Dinçer, S.; Tamerler, C.; Sarıkaya, M.; Pişkin, E.

    2008-05-01

    The aim of this study is to prepare photoresponsive peptide-azobenzene compounds which interacts with platinum surfaces specifically, in order to create smart surfaces for further novel applications in design of smart biosensors and array platforms. Here, a water-soluble azobenzene molecule, 4-hydroxyazo benzene,4-sulfonic acid was synthesized by diazo coupling reaction. A platinum-specific peptide, originally selected by a phage display technique was chemically synthesized/purchased, and conjugated with the azobenzene compound activated with carbonyldiimidazole. Both azobenzene and its conjugate were characterized (including photoresponsive properties) by FTIR, NMR, and UV-spectrophotometer. The yield of conjugation reaction estimated by ninhydrin assay was about 65%. Peptide incorporation did not restrict the light-sensitivity of azobenzene. Adsorption of both the peptide and its azobenzene conjugate was followed by Quartz Crystal Microbalance (QCM) system. The kinetic evaluations exhibited that both molecules interact platinum surfaces, quite rapidly and strongly.

  13. The influence of surface integrin binding patterns on specific biomaterial-cell interactions

    NASA Astrophysics Data System (ADS)

    Beranek, Maggi Marie

    As the future of biomaterials progresses toward bioactivity, the biomaterial surface must control non-specific protein adsorption and encourage selective protein and cell adsorption. Integrins alphavbeta3, alpha 1beta1, alpha5beta1 and alpha Mbeta2 are expressed on cells involved in endothelialization, inflammation, and intimal hyperplasia. These cellular events play a vital role in biomaterial biocompatibility, especially in the vascular environment. The overall hypothesis of these studies is that biomaterial surfaces exhibit selective integrin binding, which then specifies differential cell binding. To test this hypothesis, four specific aims were developed. The first aim was designed to determine whether metal and polymeric biomaterials exhibit selective integrin binding. The tested materials included 316L stainless steel, nitinol, gold, Elgiloy RTM, poly(D, L-lactide-co-glycolide), polycarbonate urethane and expanded polytetrafluoroethylene. Discrete integrin binding patterns were detected microscopically using integrin specific fluorescent antibodies. Stainless steel exhibited high level integrin alpha1beta 1 and low level integrin alphaMbeta2 binding pattern. This suggests that this metal surface should selectively encourage endothelial cell to inflammatory cell binding. In contrast, gold bound ten times the amount of integrin alphaMbeta2 compared to integrin alpha1beta1, which should encourage inflammatory cell adhesion. The 65/35 poly(D, L-lactide-co-glycolide) was the only polymeric biomaterial tested that had integrin binding levels comparable to metal biomaterials. Based on these observations, a combinational biomaterial with a surface pattern of 65/35 poly(D, L-lactide-co-glycolide) dots on a 316L stainless steel background was created. A pattern of high level integrin alpha1beta1 binding and low level integrin alpha Mbeta2 binding on this combinational surface indicates that this surface should selectively favor endothelial cell binding. In the second

  14. Modeling the adsorption of metal ions (Cu 2+, Ni 2+, Pb 2+) onto ACCs using surface complexation models

    NASA Astrophysics Data System (ADS)

    Faur-Brasquet, Catherine; Reddad, Zacaria; Kadirvelu, Krishna; Le Cloirec, Pierre

    2002-08-01

    Activated carbon cloths (ACCs), whose efficiency has been demonstrated for microorganics adsorption from water, were here studied in the removal of metal ions from aqueous solution. Two ACCs are investigated, they are characterized in terms of porosity parameters (BET specific surface area, percentage of microporosity) and chemical characteristics (acidic surface groups, acidity constants, point of zero charge). A first part consists in the experimental study of three metal ions removal (Cu 2+, Ni 2+ and Pb 2+) in a batch reactor. Isotherms modeling by Freundlich and Brunauer-Emmett-Teller (BET) equations enables the following adsorption order: Cu 2+>Ni 2+>Pb 2+ to be determined for adsorption capacities on a molar basis. It may be related to adsorbates characteristics in terms of electronegativity and ionic radius. The influence of adsorbent's microporosity is also shown. Adsorption experiments carried out for pH values ranging from 2 to 10 demonstrate: (i) an adsorption occurring below the precipitation pH; (ii) the strong influence of pH, with a decrease of electrostatic repulsion due to the formation of less charged hydrolyzed species coupled with a decrease of activated carbon surface charge as pH increases. The second part focuses on the modeling of adsorption versus the pH experimental data by the diffuse layer model (DLM) using Fiteql software. The model is efficient to describe the system behavior in the pH range considered. Regarding complexation constants, they show the following affinity for ACC: Pb 2+>Cu 2+>Ni 2+. They are related to initial concentrations used for the three metal ions.

  15. Identification of variant-specific surface proteins in Giardia muris trophozoites.

    PubMed

    Ropolo, Andrea S; Saura, Alicia; Carranza, Pedro G; Lujan, Hugo D

    2005-08-01

    Giardia lamblia undergoes antigenic variation, a process that might allow the parasite to evade the host's immune response and adapt to different environments. Here we show that Giardia muris, a related species that naturally infects rodents, possesses multiple variant-specific surface proteins (VSPs) and expresses VSPs on its surface, suggesting that it undergoes antigenic variation similar to that of G. lamblia.

  16. Identification of Variant-Specific Surface Proteins in Giardia muris Trophozoites

    PubMed Central

    Ropolo, Andrea S.; Saura, Alicia; Carranza, Pedro G.; Lujan, Hugo D.

    2005-01-01

    Giardia lamblia undergoes antigenic variation, a process that might allow the parasite to evade the host's immune response and adapt to different environments. Here we show that Giardia muris, a related species that naturally infects rodents, possesses multiple variant-specific surface proteins (VSPs) and expresses VSPs on its surface, suggesting that it undergoes antigenic variation similar to that of G. lamblia. PMID:16041041

  17. Microbial specificity of metallic surfaces exposed to ambient seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zaidi, B.R.; Bard, R.F.; Tosteson, T.R.

    1984-09-01

    High-molecular-weight materials associated with the extracellular matrix and film found on titanium and aluminum surfaces after exposure to flowing coastal seawater were isolated. This material was purified by hydroxylapatite chromatography and subsequently employed to produce antibodies in the toad, Bufo marinus. The antibodies were immobilized on a solid support and employed to isolate adhesion-enhancing, high-molecular-weight materials from the laboratory culture media of bacterial strains recovered from the respective metallic surfaces during the course of their exposure to seawater. The adhesion-enhancing materials produced by the surface-associated bacterial strains were immunologically related to the extracellular biofouling matrix material found on the surfacesmore » from which these bacteria were isolated. The surface selectivity of these bacterial strains appeared to be based on the specificity of the interaction between adhesion-enhancing macromolecules produced by these bacteria and the surfaces in question. 30 references, 6 tables.« less

  18. Optimal condition for fabricating superhydrophobic Aluminum surfaces with controlled anodizing processes

    NASA Astrophysics Data System (ADS)

    Saffari, Hamid; Sohrabi, Beheshteh; Noori, Mohammad Reza; Bahrami, Hamid Reza Talesh

    2018-03-01

    A single step anodizing process is used to produce micro-nano structures on Aluminum (1050) substrates with sulfuric acid as electrolyte. Therefore, surface energy of the anodized layer is reduced using stearic acid modification. Undoubtedly, effects of different parameters including anodizing time, electrical current, and type and concentration of electrolyte on the final contact angle are systemically studied and optimized. Results show that anodizing current of 0.41 A, electrolyte (sulfuric acid) concentration of 15 wt.% and anodizing time of 90 min are optimal conditions which give contact angle as high as 159.2° and sliding angle lower than 5°. Moreover, the study reveals that adding oxalic acid to the sulfuric acid cannot enhance superhydrophobicity of the samples. Also, scanning electron microscopy images of samples show that irregular (bird's nest) structures present on the surface instead of high-ordered honeycomb structures expecting from normal anodizing process. Additionally, X-ray diffraction analysis of the samples shows that only amorphous structures present on the surface. The Brunauer-Emmett-Teller (BET) specific surface area of the anodized layer is 2.55 m2 g-1 in optimal condition. Ultimately, the surface keeps its hydrophobicity in air and deionized water (DIW) after one week and 12 weeks, respectively.

  19. Effect of specific surface area of MWCNTS on surface roughness and delamination in drilling Epoxy/Glass Fabric Composite

    NASA Astrophysics Data System (ADS)

    Ponnuvel, S.; Ananth, M. Prem

    2018-03-01

    In this study the effect of specific surface area of the MWCNTs on the drilled hole qualities was investigated. Epoxy araldite LY556 with hardener HY951 and E-glass coarse plain weave fabric are used for the fabrication of reference material (specimen A). Multi-WalledCarbon Nanotubes (MWCNTs) with diameters <8 nm and 20–30 nm are used for the fabrication of study materials, namely specimen B and specimen C respectively. In specimen B the epoxy resin was filled with MWCNTs having a specific surface area >500 m2 g‑1. MWCNTs in specimen C had a specific surface area >110 m2 g‑1. Drilling experiments were conducted on all the three specimens. Two dimensional delamination factor and the surface roughness of the inner wall of the drilled holes were investigated using Grey Relational Analysis (GRA) and Analysis of variance (ANOVA). Two dimensional delamination factor showed better performance from specimen B and specimen C in comparison with specimen A suggesting improvement in the bonding between epoxy and the glass fiber in the presence of MWCNTs. Similar observations were made for surface roughness of the inner wall of the drilled holes at 1250 rpm. Whereas the presence of MWCNTs (Specimen B and specimen C) produced poor surface finish at 500 rpm in comparison with specimen A. Variations in the hole quality characteristics between specimen B and specimen C was marginal with better observations in specimen C.

  20. T-bet Down-Modulation in Tolerized Th1 Effector CD4 Cells Confers a TCR-Distal Signaling Defect That Selectively Impairs IFN-γ Expression1

    PubMed Central

    Long, Meixiao; Slaiby, Aaron M.; Hagymasi, Adam T.; Mihalyo, Marianne A.; Lichtler, Alexander C.; Reiner, Steven L.; Adler, Adam J.

    2010-01-01

    When Th1 effector CD4 cells encounter tolerizing Ag in vivo, their capacity to express the effector cytokines IFN-γ and TNF-α is lost more rapidly than noneffector functions such as IL-2 production and proliferation. To localize the relevant intracellular signaling defects, cytokine expression was compared following restimulation with Ag vs agents that bypass TCR-proximal signaling. IFN-γ and TNF-α expression were both partially rescued when TCR-proximal signaling was bypassed, indicating that both TCR-proximal and -distal signaling defects impair the expression of these two effector cytokines. In contrast, bypassing TCR-proximal signaling fully rescued IL-2 expression. T-bet, a transcription and chromatin remodeling factor that is required to direct the differentiation of naive CD4 cells into IFN-γ -expressing Th1 effectors, was partially down-modulated in tolerized Th1 effectors. Enforcing T-bet expression during tolerization selectively rescued the ability to express IFN-γ, but not TNF-α. Conversely, expression of a dominant-negative T-bet in Th1 effectors selectively impaired the ability to express IFN-γ, but not TNF-α. Analysis of histone acetylation at the IFN-γ promoter further suggested that down-modulation of T-bet expression during Th1 effector CD4 cell tolerization does not impair IFN-γ expression potential through alterations in chromatin structure. PMID:16393991

  1. Robot Towed Shortwave Infrared Camera for Specific Surface Area Retrieval of Surface Snow

    NASA Astrophysics Data System (ADS)

    Elliott, J.; Lines, A.; Ray, L.; Albert, M. R.

    2017-12-01

    Optical grain size and specific surface area are key parameters for measuring the atmospheric interactions of snow, as well as tracking metamorphosis and allowing for the ground truthing of remote sensing data. We describe a device using a shortwave infrared camera with changeable optical bandpass filters (centered at 1300 nm and 1550 nm) that can be used to quickly measure the average SSA over an area of 0.25 m^2. The device and method are compared with calculations made from measurements taken with a field spectral radiometer. The instrument is designed to be towed by a small autonomous ground vehicle, and therefore rides above the snow surface on ultra high molecular weight polyethylene (UHMW) skis.

  2. Increased numbers of pre-existing memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells1

    PubMed Central

    Joshi, Nikhil S.; Cui, Weiguo; Dominguez, Claudia; Chen, Jonathan H.; Hand, Timothy W.; Kaech, Susan M.

    2011-01-01

    Memory CD8 T cells acquire TEM properties following reinfection, and may reach terminally differentiated, senescent states (“Hayflick limit”) after multiple infections. The signals controlling this process are not well understood, but we found that the degree of 2o effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and pre-existing memory CD8 T cell number (i.e., 1o memory CD8 T cell precursor frequency) present during secondary infection. Compared to naïve cells, memory CD8 T cells were predisposed towards terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of antigen. TE cell formation following 2o or 3o infections was dependent on increased T-bet expression because T-bet+/− cells were resistant to these phenotypic changes. Larger numbers of pre-existing memory CD8 T cells limited the duration of 2o infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2o TE CD8 T cells that formed. Together, these data show that, over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with antigen or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by pre-existing memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies. PMID:21930973

  3. Selectivity/Specificity Improvement Strategies in Surface-Enhanced Raman Spectroscopy Analysis

    PubMed Central

    Wang, Feng; Cao, Shiyu; Yan, Ruxia; Wang, Zewei; Wang, Dan; Yang, Haifeng

    2017-01-01

    Surface-enhanced Raman spectroscopy (SERS) is a powerful technique for the discrimination, identification, and potential quantification of certain compounds/organisms. However, its real application is challenging due to the multiple interference from the complicated detection matrix. Therefore, selective/specific detection is crucial for the real application of SERS technique. We summarize in this review five selective/specific detection techniques (chemical reaction, antibody, aptamer, molecularly imprinted polymers and microfluidics), which can be applied for the rapid and reliable selective/specific detection when coupled with SERS technique. PMID:29160798

  4. Silane-modified surfaces in specific antibody-mediated cell recognition.

    PubMed

    Sterzynska, Karolina; Budna, Joanna; Frydrych-Tomczak, Emilia; Hreczycho, Grzegorz; Malinska, Agnieszka; Maciejewski, Hieronim; Zabel, Maciej

    2014-01-01

    The immobilization of antibodies on various surfaces has been the subject of advanced research in various immunoassay-based diagnostic devices. The physical and chemical stabilities of the immobilized antibodies on a solid surface still cause many problems because upon immobilizing antibody molecules, the antigen-binding ability usually decreases. The silanization of surfaces with organosilanes carrying chemically active groups such as (3-aminopropyl) triethoxysilane (APTES) can accommodate these antigen-binding molecules in an appropriate orientation so that their functionality and binding activity are essentially retained. In this study, n-butyltrimethoxysilane (BMS) and 3-(octafluoropentyloxy)-propyltriethoxysilane (OFPOS) were used as "blocking silanes". The aims of this study were to compare the effectiveness of specific antibody binding of APTES, APTES + BMS and APTES + OFPOS and to characterize the modified surfaces by contact angle measurements and immunofluorescence measurements prior to and after immobilizing proteins. Additionally, we have evaluated the functionality of the immobilized antibodies by their abilities to bind EpCAM-positive human colon adenocarcinoma cell line (LoVo) and EpCAM-negative mouse embryonic fibroblast cell line (3T3). Cell enumeration was conducted on the basis of DAPI-positive signals and recorded using a confocal laser scanning biological microscope. The results of our study showed that the immobilization capability and reactivity of APTES, APTES + BMS and APTES + OFPOS differ. The modification of APTES with unreactive silanes (BMS,OFPOS) is recommended to improve the antibody binding efficiency. However, using OFPOS resulted in more effective antibody and cell binding, and it appears to be the most useful compound in specific antibody-mediated cell recognition.

  5. Host-parasite coevolution can promote the evolution of seed banking as a bet-hedging strategy.

    PubMed

    Verin, Mélissa; Tellier, Aurélien

    2018-04-20

    Seed (egg) banking is a common bet-hedging strategy maximizing the fitness of organisms facing environmental unpredictability by the delayed emergence of offspring. Yet, this condition often requires fast and drastic stochastic shifts between good and bad years. We hypothesize that the host seed banking strategy can evolve in response to coevolution with parasites because the coevolutionary cycles promote a gradually changing environment over longer times than seed persistence. We study the evolution of host germination fraction as a quantitative trait using both pairwise competition and multiple mutant competition methods, while the germination locus can be genetically linked or unlinked with the host locus under coevolution. In a gene-for-gene model of coevolution, hosts evolve a seed bank strategy under unstable coevolutionary cycles promoted by moderate to high costs of resistance or strong disease severity. Moreover, when assuming genetic linkage between coevolving and germination loci, the resistant genotype always evolves seed banking in contrast to susceptible hosts. Under a matching-allele interaction, both hosts' genotypes exhibit the same seed banking strategy irrespective of the genetic linkage between loci. We suggest host-parasite coevolution as an additional hypothesis for the evolution of seed banking as a temporal bet-hedging strategy. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

  6. Bet-hedging as a complex interaction among developmental instability, environmental heterogeneity, dispersal, and life-history strategy.

    PubMed

    Scheiner, Samuel M

    2014-02-01

    One potential evolutionary response to environmental heterogeneity is the production of randomly variable offspring through developmental instability, a type of bet-hedging. I used an individual-based, genetically explicit model to examine the evolution of developmental instability. The model considered both temporal and spatial heterogeneity alone and in combination, the effect of migration pattern (stepping stone vs. island), and life-history strategy. I confirmed that temporal heterogeneity alone requires a threshold amount of variation to select for a substantial amount of developmental instability. For spatial heterogeneity only, the response to selection on developmental instability depended on the life-history strategy and the form and pattern of dispersal with the greatest response for island migration when selection occurred before dispersal. Both spatial and temporal variation alone select for similar amounts of instability, but in combination resulted in substantially more instability than either alone. Local adaptation traded off against bet-hedging, but not in a simple linear fashion. I found higher-order interactions between life-history patterns, dispersal rates, dispersal patterns, and environmental heterogeneity that are not explainable by simple intuition. We need additional modeling efforts to understand these interactions and empirical tests that explicitly account for all of these factors.

  7. Long-range correlations in an online betting exchange for a football tournament

    NASA Astrophysics Data System (ADS)

    Hardiman, Stephen J.; Richmond, Peter; Hutzler, Stefan

    2010-10-01

    We analyze the changes in the market odds of football matches in an online betting exchange, Betfair.com. We identify the statistical differences between the returns that occur when the game play is under way, which we argue are driven by match events, and the returns that occur during half-time, which we ascribe to a trader-driven noise. Furthermore, using detrended fluctuation analysis we identify anti-persistence (Hurst exponent H<0.5) in odds returns and long memory (H>0.5) in the volatilities, which we attribute to the trader-driven noise. The time series of trading volume are found to be short-memory processes.

  8. μSR Study of Organic Superconductor λ-(BETS)2GaCl4

    NASA Astrophysics Data System (ADS)

    Sari, D. P.; Asih, R.; Mohm-Tajudin, S. S.; Adam, N.; Hiraki, K.; Ishii, Y.; Takahashi, T.; Nakano, T.; Nozue, Y.; Sulaiman, S.; Mohamed-Ibrahim, M. I.; Watanabe, I.

    2017-05-01

    Muon-spin-relaxation (μSR) measurements in the transverse-field (TF) of 30 G were carried out from 7 K down to 1.8 K on the non-magnetic anion-based organic superconductor λ-(BETS)2GaCl4. The TF-μSR time spectrum showed a significant increase with the Gaussian-type damping behavior below the superconducting transition temperature TC = 5 K confirming the bulk SC state with the full volume fraction. The zero-field (ZF) μSR time spectrum did not show any change against the temperature down to 1.7 K, suggesting that the time reversal symmetry of the Cooper pair might not be broken.

  9. Effect of CMV and Aging on the Differential Expression of CD300a, CD161, T-bet, and Eomes on NK Cell Subsets.

    PubMed

    Lopez-Sejas, Nelson; Campos, Carmen; Hassouneh, Fakhri; Sanchez-Correa, Beatriz; Tarazona, Raquel; Pera, Alejandra; Solana, Rafael

    2016-01-01

    Natural killer (NK) cells are innate lymphoid cells involved in the defense against virus-infected cells and tumor cells. NK cell phenotype and function is affected with age and cytomegalovirus (CMV) latent infection. Aging affects the frequency and phenotype of NK cells, and CMV infection also contributes to these alterations. Thus, a reduction of CD56 bright NK cell subpopulation associated with age and an expansion of memory-like NK cells CD56 dim CD57 + NKG2C + probably related to CMV seropositivity have been described. NK cells express T-bet and Eomes transcription factors that are necessary for the development of NK cells. Here, we analyze the effect of age and CMV seropositivity on the expression of CD300a and CD161 inhibitory receptors, and T-bet and Eomes transcription factors in NK cell subsets defined by the expression of CD56 and CD57. CD300a is expressed by the majority of NK cells. CD56 bright NK cells express higher levels of CD300a than CD56 dim NK cells. An increase in the expression of CD300a was associated with age, whereas a decreased expression of CD161 in CD56 dim NK cells was associated with CMV seropositivity. In CD56 dim NK cells, an increased percentage of CD57 + CD300a + and a reduction in the percentage of CD161 + CD300a + cells were found to be associated with CMV seropositivity. Regarding T-bet and Eomes transcription factors, CMV seropositivity was associated with a decrease of T-bet hi in CD56 dim CD57 + NK cells from young individuals, whereas Eomes expression was increased with CMV seropositivity in both CD56 bright and CD56 dim CD57 +/- (from middle age and young individuals, respectively) and was decreased with aging in all NK subsets from the three group of age. In conclusion, CMV infection and age induce significant changes in the expression of CD300a and CD161 in NK cell subsets defined by the expression of CD56 and CD57. T-bet and Eomes are differentially expressed on NK cell subsets, and their expression is affected by CMV

  10. BET, thermal degradation, and FTIR spectras of triazine polyamine polymers.

    PubMed

    Can, Mustafa

    2017-04-01

    Here we show effect of the polyamine polymer chain length to BET isotherms. According to IUPAC classification [1], all three polymers are fitting type 1 physical adsorption isotherm with H3 hysteresis (except for EDA having H2 hysteresis). Moreover, TG and TGA analysis of polymers triazine-ethylenediamine (EDA) and triazine-triethylenetetramine (TETA) are provided. Due to the similarities of the structure, main decomposition temperatures are close to each other (between 593 K and 873 K). In order to understand change of FTIR spectra with adsorption and stripping Au(III), fresh, Au(III) adsorbed and recycled spectras of polymers measured. For further discussions about the effect of chain length to adsorption of Au(III) onto triazine polyamine polymer particles "Au (III) Uptake by Triazine Polyamine Polymers: Mechanism, Kinetic and Equilibrium Studies" Can et al. [2] (article in press).

  11. Aridity promotes bet hedging via delayed hatching: a case study with two temporary pond crustaceans along a latitudinal gradient.

    PubMed

    Pinceel, Tom; Vanschoenwinkel, Bram; Hawinkel, Wouter; Tuytens, Karen; Brendonck, Luc

    2017-05-01

    Climate change does affect not only average rainfall and temperature but also their variation, which can reduce the predictability of suitable conditions for growth and reproduction. This situation is problematic for inhabitants of temporary waters whose reproductive success depends on rainfall and evaporation that determine the length of the aquatic phase. For organisms with long-lived dormant life stages, bet hedging models suggest that a fraction of these should stay dormant during each growing season to buffer against the probability of total reproductive failure in variable environments. Thus far, however, little empirical evidence supports this prediction in aquatic organisms. We study geographic variation in delayed hatching of dormant eggs in natural populations of two crustaceans, Branchinella longirostris and Paralimnadia badia, that occur in temporary rock pools along a 725 km latitudinal aridity gradient in Western Australia. Consistent with bet hedging theory, populations of both species were characterised by delayed hatching under common garden conditions and hatching fractions decreased towards the drier end of the gradient where the probability of reproductive success was shown to be lower. This decrease was most pronounced in the species with the longer maturation time, presumably because it is more sensitive to the higher prevalence of short inundations. Overall, these findings illustrate that regional variation in climate can be reflected in differential investment in bet hedging and hints at a higher importance of delayed hatching to persist when the climate becomes harsher. Such strategies could become exceedingly relevant as determinants of vulnerability under climate change.

  12. Planar spatial correlations, anisotropy, and specific surface area of stationary random porous media

    NASA Astrophysics Data System (ADS)

    Berryman, James G.

    1998-02-01

    An earlier result of the author showed that an anisotropic spatial correlation function of a random porous medium could be used to compute the specific surface area when it is stationary as well as anisotropic by first performing a three-dimensional radial average and then taking the first derivative with respect to lag at the origin. This result generalized the earlier result for isotropic porous media of Debye et al. [J. Appl. Phys. 28, 679 (1957)]. The present article provides more detailed information about the use of spatial correlation functions for anisotropic porous media and in particular shows that, for stationary anisotropic media, the specific surface area can be related to the derivative of the two-dimensional radial average of the correlation function measured from cross sections taken through the anisotropic medium. The main concept is first illustrated using a simple pedagogical example for an anisotropic distribution of spherical voids. Then, a general derivation of formulas relating the derivative of the planar correlation functions to surface integrals is presented. When the surface normal is uniformly distributed (as is the case for any distribution of spherical voids), our formulas can be used to relate a specific surface area to easily measurable quantities from any single cross section. When the surface normal is not distributed uniformly (as would be the case for an oriented distribution of ellipsoidal voids), our results show how to obtain valid estimates of specific surface area by averaging measurements on three orthogonal cross sections. One important general observation for porous media is that the surface area from nearly flat cracks may be underestimated from measurements on orthogonal cross sections if any of the cross sections happen to lie in the plane of the cracks. This result is illustrated by taking the very small aspect ratio (penny-shaped crack) limit of an oblate spheroid, but holds for other types of flat surfaces as well.

  13. Planar spatial correlations, anisotropy, and specific surface area of stationary random porous media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berryman, J.G.

    1998-02-01

    An earlier result of the author showed that an anisotropic spatial correlation function of a random porous medium could be used to compute the specific surface area when it is stationary as well as anisotropic by first performing a three-dimensional radial average and then taking the first derivative with respect to lag at the origin. This result generalized the earlier result for isotropic porous media of Debye {ital et al.} [J. Appl. Phys. {bold 28}, 679 (1957)]. The present article provides more detailed information about the use of spatial correlation functions for anisotropic porous media and in particular shows that,more » for stationary anisotropic media, the specific surface area can be related to the derivative of the two-dimensional radial average of the correlation function measured from cross sections taken through the anisotropic medium. The main concept is first illustrated using a simple pedagogical example for an anisotropic distribution of spherical voids. Then, a general derivation of formulas relating the derivative of the planar correlation functions to surface integrals is presented. When the surface normal is uniformly distributed (as is the case for any distribution of spherical voids), our formulas can be used to relate a specific surface area to easily measurable quantities from any single cross section. When the surface normal is not distributed uniformly (as would be the case for an oriented distribution of ellipsoidal voids), our results show how to obtain valid estimates of specific surface area by averaging measurements on three orthogonal cross sections. One important general observation for porous media is that the surface area from nearly flat cracks may be underestimated from measurements on orthogonal cross sections if any of the cross sections happen to lie in the plane of the cracks. This result is illustrated by taking the very small aspect ratio (penny-shaped crack) limit of an oblate spheroid, but holds for other types of

  14. Isolation by cell-column chromatography of immunoglobulins specific for cell surface carbohydrates

    PubMed Central

    1977-01-01

    A new method of affinity chromatography using glutaraldehyde-fixed cells immobilized on Sephadex beads has been used to isolate immunoglobulins (Ig's) specific for cell surface glycoproteins. Ig's that specifically bound and agglutinated the same cells as those originally fixed on the columns were isolated from nonimmune sera of various species. Periodate treatment of the cell-columns and the free cells destroyed their ability to bind the Ig's, and the binding of the Ig's to untreated cells was inhibited by monosaccharides such as D- galactose and sialic acid. The binding of antibodies directed against cell surfaces obtained by immunizing animals with the same mouse tumor cell lines used on the columns (P388 and EL4) was not inhibited by various saccharides. Surface glycoproteins obtained from the mouse tumor cells by immunoprecipitation with the column-isolated Ig's yielded specific electrophoretic patterns that differed from those obtained using Ig's from the sera of rabbits immunized with the tumor cells. The data suggest that the Ig's isolated by cell-column chromatography were directed against carbohydrates, probably those in terminal positions of the polysaccharide portions of the tumor cell surface glycoproteins. Column-isolated Ig's specific for carbohydrates were also useful in studies of cell interactions in nonmammalian systems including Dictyostelium discoideum and Saccharomyces cerevisiae. The cell-column method appears to be adaptable to the isolation of a variety of molecules in addition to antibodies. PMID:833547

  15. Obaculactone suppresses Th1 effector cell function through down-regulation of T-bet and prolongs skin graft survival in mice.

    PubMed

    Gong, Fangyuan; Shen, Yan; Zhang, Qi; Sun, Yang; Tang, Jiayu; Tao, Feifei; Xu, Qiang

    2010-07-15

    Allograft rejection is a predominantly Th1 immune response. In this study, we showed that obaculactone, a natural compound derived from citrus fruit, prolonged skin graft survival in mice when treated after but not before transplantation. Furthermore, obaculactone inhibited alloantigen-specific production of Th1 cytokine IFN-gamma as well as proinflammatory cytokine IL-2, TNFalpha and IL-6. In parallel, IL-10 production was markedly up-regulated. Obaculactone significantly enhanced the percentage of CD4(+)CD25(+)Foxp3(+) Treg cells in the CD4(+) splenocytes without any effect on their inhibitory function. In vitro and in vivo tests showed obaculactone down-regulated T-bet expression in Th1 effector cells. Taken together, the unique immunomodulatory properties might qualify obaculactone as a putative, therapeutic compound for the treatment of Th1-driven diseases, including transplant rejection. 2010 Elsevier Inc. All rights reserved.

  16. The role of advanced reactive surface area characterization in improving predictions of mineral reaction rates

    NASA Astrophysics Data System (ADS)

    Beckingham, L. E.; Zhang, S.; Mitnick, E.; Cole, D. R.; Yang, L.; Anovitz, L. M.; Sheets, J.; Swift, A.; Kneafsey, T. J.; Landrot, G.; Mito, S.; Xue, Z.; Steefel, C. I.; DePaolo, D. J.; Ajo Franklin, J. B.

    2014-12-01

    Geologic sequestration of CO2 in deep sedimentary formations is a promising means of mitigating carbon emissions from coal-fired power plants but the long-term fate of injected CO2 is challenging to predict. Reactive transport models are used to gain insight over long times but rely on laboratory determined mineral reaction rates that have been difficult to extrapolate to field systems. This, in part, is due to a lack of understanding of mineral reactive surface area. Many models use an arbitrary approximation of reactive surface area, applying orders of magnitude scaling factors to measured BET or geometric surface areas. Recently, a few more sophisticated approaches have used 2D and 3D image analyses to determine mineral-specific reactive surface areas that account for the accessibility of minerals. However, the ability of these advanced surface area estimates to improve predictions of mineral reaction rates has yet to be determined. In this study, we fuse X-ray microCT, SEM QEMSCAN, XRD, SANS, and SEM-FIB analysis to determine mineral-specific accessible reactive surface areas for a core sample from the Nagaoka pilot CO2 injection site (Japan). This sample is primarily quartz, plagioclase, smectite, K-feldspar, and pyroxene. SEM imaging shows abundant smectite cement and grain coatings that decrease the fluid accessibility of other minerals. However, analysis of FIB-SEM images reveals that smectite nano-pores are well connected such that access to underlying minerals is not occluded by smectite coatings. Mineral-specific accessible surfaces are determined, accounting for the connectivity of the pore space with and without connected smectite nano-pores. The large-scale impact of variations in accessibility and dissolution rates are then determined through continuum scale modeling using grid-cell specific information on accessible surface areas. This approach will be compared with a traditional continuum scale model using mineral abundances and common surface area

  17. 40 CFR 761.372 - Specific requirements for relatively clean surfaces.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Specific requirements for relatively clean surfaces. 761.372 Section 761.372 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING...

  18. Free-standing and porous hierarchical nanoarchitectures constructed with cobalt cobaltite nanowalls for supercapacitors with high specific capacitances

    NASA Astrophysics Data System (ADS)

    Xiao, Yuanhua; Zhang, Aiqin; Liu, Shaojun; Zhao, Jihong; Fang, Shaoming; Jia, Dianzeng; Li, Feng

    2012-12-01

    Free-standing and porous hierarchical nanoarchitectures constructed with cobalt cobaltite (Co3O4) nanowalls have been successfully synthesized in large scale by calcining three dimensional (3D) hierarchical nanostructures consisting of single crystalline cobalt carbonate hydroxide hydrate - Co(CO3)0.5(OH)·0.11H2O nanowalls prepared with a solvothermal method. The step-by-step decomposition of the precursor can generate porous Co3O4 nanowalls with BET surface area of 88.34 m2 g-1. The as-prepared Co3O4 nanoarchitectures show superior specific capacitance to the most Co3O4 supercapacitor electrode materials to date. After continuously cycled for 1000 times of charge-discharge at 4 A g-1, the supercapacitors can retain ca 92.3% of their original specific capacitances. The excellent performances of the devices can be attributed to the porous and hierarchical 3D nanostructure of the materials.

  19. Power Spectral Density Specification and Analysis of Large Optical Surfaces

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2009-01-01

    The 2-dimensional Power Spectral Density (PSD) can be used to characterize the mid- and the high-spatial frequency components of the surface height errors of an optical surface. We found it necessary to have a complete, easy-to-use approach for specifying and evaluating the PSD characteristics of large optical surfaces, an approach that allows one to specify the surface quality of a large optical surface based on simulated results using a PSD function and to evaluate the measured surface profile data of the same optic in comparison with those predicted by the simulations during the specification-derivation process. This paper provides a complete mathematical description of PSD error, and proposes a new approach in which a 2-dimentional (2D) PSD is converted into a 1-dimentional (1D) one by azimuthally averaging the 2D-PSD. The 1D-PSD calculated this way has the same unit and the same profile as the original PSD function, thus allows one to compare the two with each other directly.

  20. Egg shell waste as heterogeneous nanocatalyst for biodiesel production: Optimized by response surface methodology.

    PubMed

    Pandit, Priti R; Fulekar, M H

    2017-08-01

    Worldwide consumption of hen eggs results in availability of large amount of discarded egg waste particularly egg shells. In the present study, the waste shells were utilized for the synthesis of highly active heterogeneous calcium oxide (CaO) nanocatalyst to transesterify dry biomass into methyl esters (biodiesel). The CaO nanocatalyst was synthesied by calcination-hydration-dehydration technique and fully characterized by infrared spectroscopy, X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), brunauer-emmett-teller (BET) elemental and thermogravimetric analysis. TEM image showed that the nano catalyst had spherical shape with average particle size of 75 nm. BET analysis indicated that the catalyst specific surface area was 16.4 m 2  g -1 with average pore diameter of 5.07 nm. The effect of nano CaO catalyst was investigated by direct transesterification of dry biomass into biodiesel along with other reaction parameters such as catalyst ratio, reaction time and stirring rate. The impact of the transesterification reaction parameters and microalgal biodiesel yield were analyzed by response surface methodology based on a full factorial, central composite design. The significance of the predicted mode was verified and 86.41% microalgal biodiesel yield was reported at optimal parameter conditions 1.7% (w/w), catalyst ratio, 3.6 h reaction time and stirring rate of 140.6 rpm. The biodiesel conversion was determined by 1 H nuclear magnetic resonance spectroscopy (NMR). The fuel properties of prepared biodiesel were found to be highly comply with the biodiesel standard ASTMD6751 and EN14214. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Tailoring surface and photocatalytic properties of ZnO and nitrogen-doped ZnO nanostructures using microwave-assisted facile hydrothermal synthesis

    NASA Astrophysics Data System (ADS)

    Rangel, R.; Cedeño, V.; Ramos-Corona, A.; Gutiérrez, R.; Alvarado-Gil, J. J.; Ares, O.; Bartolo-Pérez, P.; Quintana, P.

    2017-08-01

    Microwave hydrothermal synthesis, using an experimental 23 factorial design, was used to produce tunable ZnO nano- and microstructures, and their potential as photocatalysts was explored. Photocatalytic reactions were conducted in a microreactor batch system under UV and visible light irradiation, while monitoring methylene blue degradation, as a model system. The variables considered in the microwave reactor to produce ZnO nano- or microstructures, were time, NaOH concentration and synthesis temperature. It was found that, specific surface area and volume/surface area ratio were affected as a consequence of the synthesis conditions. In the second stage, the samples were plasma treated in a nitrogen atmosphere, with the purpose of introducing nitrogen into the ZnO crystalline structure. The central idea is to induce changes in the material structure as well as in its optical absorption, to make the plasma-treated material useful as photocatalyst in the visible region of the electromagnetic spectrum. Pristine ZnO and nitrogen-doped ZnO compounds were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area (BET), XPS, and UV-Vis diffuse reflectance spectroscopy. The results show that the methodology presented in this work is effective in tailoring the specific surface area of the ZnO compounds and incorporation of nitrogen into their structure, factors which in turn, affect its photocatalytic behavior.

  2. Surface and adsorptive properties of Moringa oleifera bark for removal of V(V) from aqueous solutions.

    PubMed

    Mnisi, Robert Londi; Ndibewu, Peter Papoh

    2017-11-04

    The bark of Moringa oleifera, a cheap and readily available natural biopolymeric resource material, found to significantly reduce coliform load and turbidity in contaminated water is investigated in this paper. Its surface and adsorptive properties are investigated to explore its adsorptive potential in removing V(V) from aqueous solutions. Surface properties were investigated using FTIR, HRSEM/EDS, IC, and BET-N 2 adsorption techniques. Adsorptive properties were investigated by optimizing adsorption parameters such as pH, temperature, initial metal concentration, and adsorbent dosage, using V(V) as an adsorbate. The adsorption-desorption isotherms are typical of type II with a H3 hysteresis loop and is characteristic of a largely macroporous material. Bottle ink pores are observed, which can provide good accessibility of the active sites, even though the internal BET surface area is typically low (1.79 g/m 2 ). Solution pH significantly influences the adsorptive potential of the material. The low surface area negatively impacts on the adsorption capacity, but is compensated for by the exchangeable anions (Cl - , F - , PO 4 3- , NO 3 - , and SO 4 2- ) and cations (Ca 2+ , K + , Mg 2+ , and Al 3+ ) at the surface and the accessibility of the active sites. Adsorption isotherm modeling show that the surface is largely heterogeneous with complex multiple sites and adsorption is not limited to monolayer.

  3. miR-29a-3p/T-bet Regulatory Circuit Is Altered in T Cells of Patients With Hashimoto's Thyroiditis.

    PubMed

    Tokić, Stana; Štefanić, Mario; Glavaš-Obrovac, Ljubica; Kishore, Amit; Navratilova, Zdenka; Petrek, Martin

    2018-01-01

    Hashimoto's thyroiditis (HT) is a common autoimmune thyroid disorder that frequently evolves from asymptomatic, T-cell mediated chronic inflammation toward overt hypothyroidism. Previously, we have demonstrated a role for T-bet, a T helper 1/CD8 + T cell transcription factor (TF), and FoxP3, a regulatory T cell TF, in disease progression and severity, but the basis behind their altered mRNA expression remains unknown. In this study, we aimed to leverage the role for microRNAs, representing negative transcriptional regulators, across the spectrum of HT clinical presentations using the same, well-characterized RNA sample cohort. Ten hypothyroid, untreated patients (hypoHT), 10 hypothyroid cases rendered euthyroid by l-thyroxine therapy (substHT), 11 spontaneously euthyroid HT subjects (euHT), and 10 healthy controls (ctrl) were probed for three candidate immunoregulatory miRNA (miR-9-5p, miR-29a-3p, and miR-210-3p) using quantitative real-time PCR measurements. Data were normalized to U6snRNA and fold difference in expression calculated by the efficiency corrected 2 -ΔΔCt model. Compared to healthy controls, peripheral blood (PB) T cells of HT patients exhibited significantly diminished miR-29a-3p expression levels [median expression levels (IQR), HT vs CTRL, 0.62 (0.44-1.01) vs 1.373 (0.63-2.7), P  = 0.046], and a similar, but not significant decline in miR-210-3p abundance [HT vs CTRL, 0.64 (0.39-1.31) vs 1.2 (0.5-2.56), P  = 0.24, Wilcoxon test]. A significant inverse correlation was observed between the two differentially expressed transcripts, T-bet mRNA and miR-29a-3p. Moreover, altered miR-29a-3p/T-bet expression in T cells of untreated HT patients was related to low serum FT4, high serum thyrotropin, and decreased thyroid volumes. Of note, miR-210-3p expression was positively correlated to HIF1α, and inversely to FoxP3 mRNA levels, but no evidence of differential expression for any of these miRNA-mRNA pairs was observed. Finally, miR-9-5p

  4. Corn stalks char from fast pyrolysis as precursor material for preparation of activated carbon in fluidized bed reactor.

    PubMed

    Wang, Zhiqi; Wu, Jingli; He, Tao; Wu, Jinhu

    2014-09-01

    Corn stalks char from fast pyrolysis was activated by physical and chemical activation process in a fluidized bed reactor. The structure and morphology of the carbons were characterized by N2 adsorption and SEM. Effects of activation time and activation agents on the structure of activation carbon were investigated. The physically activated carbons with CO2 have BET specific surface area up to 880 m(2)/g, and exhibit microporous structure. The chemically activated carbons with H3PO4 have BET specific surface area up to 600 m(2)/g, and exhibit mesoporous structure. The surface morphology shows that physically activated carbons exhibit fibrous like structure in nature with long ridges, resembling parallel lines. Whereas chemically activated carbons have cross-interconnected smooth open pores without the fibrous like structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Preparation and recognition of surface molecularly imprinted core-shell microbeads for protein in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Lu, Yan; Yan, Chang-Ling; Gao, Shu-Yan

    2009-04-01

    In this paper, a surface molecular imprinting technique was reported for preparing core-shell microbeads of protein imprinting, and bovine hemoglobin or bovine serum albumin were used as model proteins for studying the imprinted core-shell microbeads. 3-Aminophenylboronic acid (APBA) was polymerized onto the surface of polystyrene microbead in the presence of the protein templates to create protein-imprinted core-shell microbeads. The various samples were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) methods. The effect of pH on rebinding of the template hemoglobin, the specific binding and selective recognition were studied for the imprinted microbeads. The results show that the bovine hemoglobin-imprinted core-shell microbeads were successfully created. The shell was a sort of imprinted thin films with porous structure and larger surface areas. The imprinted microbeads have good selectivity for templates and high stability. Due to the recognition sites locating at or closing to the surface, these imprinted microbeads have good property of mass-transport. Unfortunately, the imprint technology was not successfully applied to imprinting bovine serum albumin (BSA).

  6. Surface characterization studies of walnut-shell biochar catalysts for simultaneously removing of organic sulfur from yellow phosphorus tail gas

    NASA Astrophysics Data System (ADS)

    Song, Xin; Li, Kai; Ning, Ping; Wang, Chi; Sun, Xin; Tang, Lihong; Ruan, Haotian; Han, Shuang

    2017-12-01

    The influences of different preparation conditions for surface characteristics on removing organic sulfur were studied. From BET, XRD, FTIR, DRIFTS, TG/DTA, CO2-TPD results, it can be seen that these preparation conditions had great influences on the pore structure, specific surface area, crystal structure and surface functional groups. The micropore volume, amorphous structure and alkalinity site strength played major roles in desulfurization process. H2S was oxidized by oxygen containing functional groups, such as sbnd COO, sbnd Cdbnd O. H2O molecule could be converted into some groups, such as sbnd CH and Csbnd OH groups, and promoted the hydrolysis reaction. The strong alkalinity site was the key factor for chemical adsorption and hydrolysis. H2O molecule, sbnd CH, Csbnd OH groups promoted the hydrolysis reaction and sbnd COO, sbnd Cdbnd O groups promoted the oxidation of H2S on the surface of WSB. Meanwhile, the main desulfurization process over WSB after carbonization was adsorption and it changed to hydrolysis reaction after activation on the surface of WSB. Furthermore, the reaction mechanism was investigated by DRIFTS measurement according to the change of surface functional groups.

  7. Organic and inorganic molecules as probes of mineral surfaces (Invited)

    NASA Astrophysics Data System (ADS)

    Sverjensky, D. A.

    2010-12-01

    Although the multi-site nature of mineral surfaces is to be expected based on the underlying crystal structure, definitive evidence of the need to use more than one site in modelling proton surface charge or adsorption of a single adsorbate at the mineral-water interface is lacking. Instead, a single-site approach affords a practical way of averaging over all possible crystal planes and sites in a powdered mineral sample. Extensive analysis of published proton surface charge and adsorption of metals on oxide mineral surfaces can be undertaken with a single site density for each mineral based on tritium exchange or estimation from averages of the site densities of likely exposed surfaces. Even in systems with competing metals (e.g. Cu and Pb on hematite), the same site density as used for proton surface charge can be employed depending on the reaction stoichiometry. All of this indicates that protons and metals can bind to a great variety of sites with the same overall site density. However, simple oxyanions such as carbonate, sulfate, selenate, arsenate and arsenite require a much lower site density for a given mineral. For example, on goethite these oxyanions utilize a site density that correlates with the BET surface area of the goethite. In this way, the oxyanions can be thought of as selectively probing the available sites on the mineral. The correlation probably arises because goethites with different BET surface areas have different proportions of singly and multiply-bonded oxygens, and only the singly-bonded oxygens are useful for inner-sphere surface complexation by the ligand exchange mechanism. Small organic molecules behave in a remarkably similar way. For example, adsorption of oxalate on goethite, and aspartate, glutamate, dihydroxyphenylalanine, lysine and arginine on rutile are all consistent with a much smaller site density than those required for metals such as calcium or neodymium. Overall, these results suggest that both inorganic oxyanions and

  8. Synthesis and structural characteristics of high surface area TiO2 aerogels by ultrasonic-assisted sol-gel method

    NASA Astrophysics Data System (ADS)

    Qingge, Feng; Huidong, Cai; Haiying, Lin; Siying, Qin; Zheng, Liu; Dachao, Ma; Yuyang, Ye

    2018-02-01

    TiO2 aerogel is a unique three-dimensional porous nano-particle material with the characteristics of high specific surface area and good light transmittance. In this paper, a novel method involving ultrasonic-assisted sol-gel, solvent exchange, and vacuum drying was successfully developed to synthesis the TiO2 aerogel. The morphology and properties of the prepared TiO2 aerogels were characterized by the Brunauer-Emmett-Teller theory (BET), x-ray diffraction, field-emission scanning electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis-differential thermal analysis, Fourier transform infrared spectroscopy, and Raman spectroscopy. The adsorption and photocatalytic activity of TiO2 aerogels was evaluated by monitoring the degradation of Rhodamine B solution. Our results indicated that: (1) with an optimum ratio of Ti:H2O = 8:1 the BET surface area, average pore diameter, and total pore volume of TiO2 aerogel are enhanced to 563.6 m2 g-1, 3.01 nm, and 0.42 cm3 g-1, respectively; (2) the TiO2 aerogels possessed controllable crystal form depending on the thermal treatments conditions. The crystal face (101) of anatase, complete anatase, mixed state of anatase and rutile, and rutile were obtained by increasing the temperature from 200 °C-300 °C, from 400 °C-500 °C, 600 °C, and from 700 °C-1000 °C, respectively; and (3) the excellent catalytic activity of the as-prepared TiO2 aerogels for the ultraviolet photolytic degradation of Rhodamine B had attributed to the synergistic effect of adsorption and photoactivity.

  9. Impact of Plasma Surface Treatment on Bamboo Charcoal/silver Nanocomposite

    NASA Astrophysics Data System (ADS)

    Vignesh, K.; Vijayalakshmi, K. A.; Karthikeyan, N.

    2016-10-01

    Bamboo charcoal (BC) accompanied silver (Ag) nanocomposite is synthesized through sol-gel method. The produced BC/Ag nanocomposite was surface modified by air and oxygen plasma treatments. Silver ions (Ag+) will serve to improve the antibacterial activity as well as the surface area of BC. Plasma treatment has improved the surface functional groups, crystalline intensity and antibacterial activity of the prepared nanocomposite. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies show that Ag nanoparticles have good agreement with BC and the particle size has a mean diameter of 20-40nm. We observe the carboxyl functional groups in Fourier transform infrared spectroscopy (FTIR) after the oxygen plasma treatment. Moreover surface area and adsorption were analyzed by using the Brunauer, Emmett and Teller (BET) surface area (SBET) and UV-Vis spectroscopy.

  10. Nano- to Formation-Scale Estimates of Mineral-Specific Reactive Surface Area

    NASA Astrophysics Data System (ADS)

    Cole, D. R.; Swift, A.; Sheets, J.; Anovitz, L. M.

    2017-12-01

    Predictions of changes in fluid composition, coupled with the evolution of the solid matrix, include the generation and testing of reactive transport models. However, translating a heterogeneous natural system into physical and chemical model parameters, including the critical but poorly-constrained metric of fluid-accessible surface area, continues to challenge Earth scientists. Studies of carbon storage capacity, permeability, rock strain due to mineral dissolution and precipitation, or the prediction of rock evolution through diagenesis and weathering each consider macroscale outcomes of processes that often are critically impacted by rock surface geometry at the nanoscale. The approach taken here is to consider the whole vertical extent of a saline reservoir and then to address two questions. First, what is the accessible surface area for each major mineral, and for all adjacent pore sizes from <2 nm on up, within each major lithofacies in that formation? Second, with the formation thus divided into units of analysis, parameterized, and placed into geologic context, what constraints can be placed on reactive surface area as a function of mineral composition? A complex sandstone covering a substantial fraction of the quartz-K-feldspar-illite ternary is selected and mineral-specific surface area quantified using neutron scattering, nitrogen and mercury porosimetry, multi-signal high-resolution mineral mapping, and other techniques. For neutron scattering, scale-specific pore geometries enable more accurate translation of volume into surface area. By applying this workflow to all end-member lithologies of this reservoir formation, equations and maps of surface area as a function of position on a quartz-feldspar-clay ternary plot are developed for each major mineral. Results from this work therefore advance our ability to parameterize models not just for the particular formation studied, but for similar geologic units as well.

  11. Structure-Based Discovery of 4-(6-Methoxy-2-methyl-4-(quinolin-4-yl)-9 H -pyrimido[4,5- b ]indol-7-yl)-3,5-dimethylisoxazole (CD161) as a Potent and Orally Bioavailable BET Bromodomain Inhibitor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Yujun; Bai, Longchuan; Liu, Liu

    We have designed and synthesized 9H-pyrimido[4,5-b]indole-containing compounds to obtain potent and orally bioavailable BET inhibitors. By incorporation of an indole or a quinoline moiety to the 9H-pyrimido[4,5-b]indole core, we identified a series of small molecules showing high binding affinities to BET proteins and low nanomolar potencies in inhibition of cell growth in acute leukemia cell lines. One such compound, 4-(6-methoxy-2-methyl-4-(quinolin-4-yl)-9H-pyrimido[4,5-b]indol-7-yl)-3,5-dimethylisoxazole (31) has excellent microsomal stability and good oral pharmacokinetics in rats and mice. Orally administered, 31 achieves significant antitumor activity in the MV4;11 leukemia and MDA-MB-231 triple-negative breast cancer xenograft models in mice. Determination of the cocrystal structure of 31more » with BRD4 BD2 provides a structural basis for its high binding affinity to BET proteins. Testing its binding affinities against other bromodomain-containing proteins shows that 31 is a highly selective inhibitor of BET proteins. Our data show that 31 is a potent, selective, and orally active BET inhibitor.« less

  12. Characterization of activated carbon prepared from chicken waste and coal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yan Zhang; Hong Cui; Riko Ozao

    Activated carbons (ACs) were prepared from chicken waste (CW) and coal (E-coal) blended at the ratios of 100:0, 80:20, 50:50, 20:80, and 0:100. The process included carbonization in flowing gaseous nitrogen (300 mL min{sup -1}) at ca. 430{sup o}C for 60 min and successive steam activation (0.1 mL min{sup -1} water injection with a flow of N{sub 2} at 100 mL min{sup -1}) at 650{sup o}C for 30 min. Chicken waste is low in sulfur content but is high in volatile matter (about 55 wt %), and ACs with higher specific surface area were more successfully obtained by mixing withmore » coal. The specific surface area of the CW/Coal blend AC can be estimated by SSA{sub BET} = -65.8x{sup 2} + 158x + 168, where SSA{sub BET} is the specific surface area in m{sup 2} g{sup -1} as determined by the BET method using CO{sub 2} as the adsorbent, where x is the coal fraction by weight in the CW/coal blend ranging from 0.0 to 1.0 (e.g., x = 0.0 signifies the blend contains no coal and x = 1.0 signifies the blend consists of 100% coal). 26 refs., 7 figs., 3 tabs.« less

  13. Better Bet-Hedging with coupled positive and negative feedback loops

    NASA Astrophysics Data System (ADS)

    Narula, Jatin; Igoshin, Oleg

    2011-03-01

    Bacteria use the phenotypic heterogeneity associated with bistable switches to distribute the risk of activating stress response strategies like sporulation and persistence. However bistable switches offer little control over the timing of phenotype switching and first passage times (FPT) for individual cells are found to be exponentially distributed. We show that a genetic circuit consisting of interlinked positive and negative feedback loops allows cells to control the timing of phenotypic switching. Using a mathematical model we find that in this system a stable high expression state and stable low expression limit cycle coexist and the FPT distribution for stochastic transitions between them shows multiple peaks at regular intervals. A multimodal FPT distribution allows cells to detect the persistence of stress and control the rate of phenotype transition of the population. We further show that extracellular signals from cell-cell communication that change the strength of the feedback loops can modulate the FPT distribution and allow cells even greater control in a bet-hedging strategy.

  14. Enhanced specific surface area by hierarchical porous graphene aerogel/carbon foam for supercapacitor

    NASA Astrophysics Data System (ADS)

    Xin, Zhaopeng; Li, Weixin; Fang, Wei; He, Xuan; Zhao, Lei; Chen, Hui; Zhang, Wanqiu; Sun, Zhimin

    2017-12-01

    In this work, graphene aerogel/carbon foam is prepared by in situ inducing graphene aerogels in the pores of carbon foam. This novel hierarchical porous structure possesses a higher specific surface area as the introduction of graphene aerogels in carbon foam increases the proportion of micropores thus making it a superior candidate as electrodes for supercapacitors. The characterization and comparison of various properties of carbon foam and graphene aerogels/carbon foam have been investigated systematically. The result shows that specific surface area is up to 682.8 m2/g compared with initial carbon foam which increased about 55%, and the pore distribution curve shows more pore volume at 0.3 nm for F-CF/GA. It is demonstrated that the introduction of graphene aerogels not only increases the specific surface area, but also improves the conductivity, thus resulting in the reduction of the internal resistance and the improvement of the electrochemical performance. Consequently, graphene aerogel/carbon foam shows an excellent specific capacitance of 193.1 F/g at 1 A/g which is 72% higher than that of carbon foam acted as electrodes for supercapacitors.

  15. A feasible strategy to balance the crystallinity and specific surface area of metal oxide nanocrystals

    NASA Astrophysics Data System (ADS)

    Zhang, Q. P.; Xu, X. N.; Liu, Y. T.; Xu, M.; Deng, S. H.; Chen, Y.; Yuan, H.; Yu, F.; Huang, Y.; Zhao, K.; Xu, S.; Xiong, G.

    2017-04-01

    Practical, efficient synthesis of metal oxide nanocrystals with good crystallinity and high specific surface area by a modified polymer-network gel method is demonstrated, taking ZnO nanocrystals as an example. A novel stepwise heat treatment yields significant improvement in crystal quality. Such nanophase materials can effectively degrade common organic dyes under solar radiation and can perform very well in photo-assisted detection of NO2 gas. Other typical metal oxide nanocrystals with good crystallinity and high specific surface area were also synthesized successfully under similar conditions. This work provides a general strategy for the synthesis of metal oxide nanocrystals, balancing the crystallinity and specific surface area.

  16. Assessing the Increase in Specific Surface Area for Electrospun Fibrous Network due to Pore Induction.

    PubMed

    Katsogiannis, Konstantinos Alexandros G; Vladisavljević, Goran T; Georgiadou, Stella; Rahmani, Ramin

    2016-10-26

    The effect of pore induction on increasing electrospun fibrous network specific surface area was investigated in this study. Theoretical models based on the available surface area of the fibrous network and exclusion of the surface area lost due to fiber-to-fiber contacts were developed. The models for calculation of the excluded area are based on Hertzian, Derjaguin-Muller-Toporov (DMT), and Johnson-Kendall-Roberts (JKR) contact models. Overall, the theoretical models correlated the network specific surface area to the material properties including density, surface tension, Young's modulus, Poisson's ratio, as well as network physical properties, such as density and geometrical characteristics including fiber radius, fiber aspect ratio and network thickness. Pore induction proved to increase the network specific surface area up to 52%, compared to the maximum surface area that could be achieved by nonporous fiber network with the same physical properties and geometrical characteristics. The model based on Johnson-Kendall-Roberts contact model describes accurately the fiber-to-fiber contact area under the experimental conditions used for pore generation. The experimental results and the theoretical model based on Johnson-Kendall-Roberts contact model show that the increase in network surface area due to pore induction can reach to up to 58%.

  17. Species specific isotope dilution for the accurate and SI traceable determination of arsenobetaine and methylmercury in cuttlefish and prawn.

    PubMed

    Kumkrong, Paramee; Thiensong, Benjaporn; Le, Phuong Mai; McRae, Garnet; Windust, Anthony; Deawtong, Suladda; Meija, Juris; Maxwell, Paulette; Yang, Lu; Mester, Zoltán

    2016-11-02

    Methods based on species specific isotope dilution were developed for the accurate and SI traceable determination of arsenobetaine (AsBet) and methylmercury (MeHg) in prawn and cuttlefish tissues by LC-MS/MS and SPME GC-ICPMS. Quantitation of AsBet and MeHg were achieved by using a 13 C-enriched AsBet spike (NRC CRM CBET-1) and an enriched spike of Me 198 Hg (NRC CRM EMMS-1), respectively, wherein analyte mass fractions in enriched spikes were determined by reverse isotope dilution using natural abundance AsBet and MeHg primary standards. Purity of these primary standards were characterized by quantitative 1 H-NMR with the use of NIST SRM 350b benzoic acid as a primary calibrator, ensuring the final measurement results traceable to SI. Validation of employed methods of ID LC-MS/MS and ID SPME GC-ICPMS was demonstrated by analysis of several biological CRMs (DORM-4, TORT-3, DOLT-5, BCR-627 and BCR-463) with satisfying results. The developed methods were applied for the determination of AsBet and MeHg in two new certified reference materials (CRMs) prawn (PRON-1) and cuttlefish (SQID-1) produced jointly by Thailand Institute of Scientific and Technological Research (TISTR) and National Research Council Canada (NRC). With additional measurements of AsBet using LC-ICPMS with standard additions calibration and external calibration at NRC and TISTR, respectively, certified values of 1.206 ± 0.058 and 13.96 ± 0.54 mg kg -1 for AsBet as As (expanded uncertainty, k = 2) were obtained for the new CRMs PRON-1 and SQID-1, respectively. The reference value of 0.324 ± 0.028 mg kg -1 as Hg (expanded uncertainty, k = 2) for MeHg was obtained for the SQID-1 based on the results obtained by ID SPME GC-ICPMS method only, whereas MeHg in PRON-1 was found to be < 0.015 mg kg -1 . It was found that AsBet comprised 69.7% and 99.0% of total As in the prawn and cuttlefish, respectively, whereas MeHg comprised 94.5% of total Hg in cuttlefish. Crown Copyright © 2016

  18. Seasonality can induce coexistence of multiple bet-hedging strategies in Dictyostelium discoideum via storage effect.

    PubMed

    Martínez-García, Ricardo; Tarnita, Corina E

    2017-08-07

    The social amoeba Dictyostelium discoideum has been recently suggested as an example of bet-hedging in microbes. In the presence of resources, amoebae reproduce as unicellular organisms. Resource depletion, however, leads to a starvation phase in which the population splits between aggregators, which form a fruiting body made of a stalk and resistant spores, and non-aggregators, which remain as vegetative cells. Spores are favored when starvation periods are long, but vegetative cells can exploit resources in environments where food replenishes quickly. The investment in aggregators versus non-aggregators can therefore be understood as a bet-hedging strategy that evolves in response to stochastic starvation times. A genotype (or strategy) is defined by the balance between each type of cells. In this framework, if the ecological conditions on a patch are defined in terms of the mean starvation time (i.e. time between the onset of starvation and the arrival of a new food pulse), a single genotype dominates each environment, which is inconsistent with the huge genetic diversity observed in nature. Here we investigate whether seasonality, represented by a periodic, wet-dry alternation in the mean starvation times, allows the coexistence of several strategies in a single patch. We study this question in a non-spatial (well-mixed) setting in which different strains compete for a common pool of resources over a sequence of growth-starvation cycles. We find that seasonality induces a temporal storage effect that can promote the stable coexistence of multiple genotypes. Two conditions need to be met in our model. First, there has to be a temporal niche partitioning (two well-differentiated habitats within the year), which requires not only different mean starvation times between seasons but also low variance within each season. Second, each season's well-adapted strain has to grow and create a large enough population that permits its survival during the subsequent

  19. Acid leaching of natural chrysotile asbestos to mesoporous silica fibers

    NASA Astrophysics Data System (ADS)

    Maletaškić, Jelena; Stanković, Nadežda; Daneu, Nina; Babić, Biljana; Stoiljković, Milovan; Yoshida, Katsumi; Matović, Branko

    2018-04-01

    Nanofibrous silica with a high surface area was produced from chrysotile by the acid-leaching method. Natural mineral chrysotile asbestos from Stragari, Korlace in Serbia was used as the starting material. The fibers were modified by chemical treatment with 1 M HCl and the mineral dissolution was monitored by transmission electron microscopy, X-ray powder diffraction, inductively coupled plasma spectrometry and low-temperature nitrogen adsorption techniques to highlight the effects of the leaching process. The results showed that the applied concentration of acid solution and processing time of 4 h were sufficient to effectively remove the magnesium hydroxide layer and transform the crystal structure of the hazardous starting chrysotile to porous SiO2 nanofibers. With prolonged acid leaching, the specific surface area, S BET, calculated by BET equation, was increased from 147 up to 435 m2 g- 1, with micropores representing a significant part of the specific surface.

  20. Combined inhibition of BET family proteins and histone deacetylases as a potential epigenetics-based therapy for pancreatic ductal adenocarcinoma

    PubMed Central

    Mazur, Pawel K; Herner, Alexander; Mello, Stephano S; Wirth, Matthias; Hausmann, Simone; Sánchez-Rivera, Francisco J; Lofgren, Shane M; Kuschma, Timo; Hahn, Stephan A; Vangala, Deepak; Trajkovic-Arsic, Marija; Gupta, Aayush; Heid, Irina; Noël, Peter B; Braren, Rickmer; Erkan, Mert; Kleeff, Jörg; Sipos, Bence; Sayles, Leanne C; Heikenwalder, Mathias; Heßmann, Elisabeth; Ellenrieder, Volker; Esposito, Irene; Jacks, Tyler; Bradner, James E; Khatri, Purvesh; Sweet-Cordero, E Alejandro; Attardi, Laura D; Schmid, Roland M; Schneider, Guenter; Sage, Julien; Siveke, Jens T

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human cancers and shows resistance to any therapeutic strategy used. Here we tested small-molecule inhibitors targeting chromatin regulators as possible therapeutic agents in PDAC. We show that JQ1, an inhibitor of the bromodomain and extraterminal (BET) family of proteins, suppresses PDAC development in mice by inhibiting both MYC activity and inflammatory signals. The histone deacetylase (HDAC) inhibitor SAHA synergizes with JQ1 to augment cell death and more potently suppress advanced PDAC. Finally, using a CRISPR-Cas9–based method for gene editing directly in the mouse adult pancreas, we show that de-repression of p57 (also known as KIP2 or CDKN1C) upon combined BET and HDAC inhibition is required for the induction of combination therapy–induced cell death in PDAC. SAHA is approved for human use, and molecules similar to JQ1 are being tested in clinical trials. Thus, these studies identify a promising epigenetic-based therapeutic strategy that may be rapidly implemented in fatal human tumors. PMID:26390243

  1. Pollen derived low molecular compounds enhance the human allergen specific immune response in vivo.

    PubMed

    Gilles-Stein, S; Beck, I; Chaker, A; Bas, M; McIntyre, M; Cifuentes, L; Petersen, A; Gutermuth, J; Schmidt-Weber, C; Behrendt, H; Traidl-Hoffmann, C

    2016-10-01

    Besides allergens, pollen release bioactive, low molecular weight compounds that modulate and stimulate allergic reactions. Clinical relevance of these substances has not been investigated to date. To elucidate the effect of a non-allergenic, low molecular weight factors from aqueous birch pollen extracts (Bet-APE < 3 kDa) on the human allergic immune response in vivo. Birch and grass pollen allergic individuals underwent skin prick testing with allergen alone, allergen plus Bet-APE < 3 kDa, or allergen plus pre-identified candidate substances from low molecular pollen fraction. Nasal allergen challenges were performed in non-atopic and pollen allergic individuals using a 3 day repeated threshold challenge battery. Subjects were either exposed to allergen alone or to allergen plus Bet-APE< 3 kDa. Local cytokine levels, nasal secretion weights, nasal congestion and symptom scores were determined. Skin prick test reactions to pollen elicited larger weals when allergens were tested together with the low molecular weight compounds from pollen. Similar results were obtained with candidate pollen-associated lipid mediators. In nasal lining fluids of allergic patients challenged with allergen plus Bet-APE < 3 kDa, IL-8 and IgE was significantly increased as compared to allergen-only challenged patients. These patients also produced increased amounts of total nasal secretion and reported more severe rhinorrhea than the allergen-only challenged group. Low molecular compounds from pollen enhance the allergen specific immune response in the skin and nose. They are therefore of potential clinical relevance in allergic patients. © 2016 John Wiley & Sons Ltd.

  2. Fra a 1.02 Is the Most Potent Isoform of the Bet v 1-like Allergen in Strawberry Fruit.

    PubMed

    Franz-Oberdorf, Katrin; Eberlein, Bernadette; Edelmann, Kathrin; Hücherig, Stephanie; Besbes, Fatma; Darsow, Ulf; Ring, Johannes; Schwab, Wilfried

    2016-05-11

    The strawberry fruit proteins Fra a 1.01E-1.08 are homologues of the major birch pollen allergen Bet v 1. Three of the proteins are known to have essential biological functions in pigment formation during fruit ripening and seem to be responsible for allergic reactions to strawberry fruit. We evaluated the cross-reactive allergenic potential of these putative strawberry allergens in patients allergic to birch pollen. Activation of basophils of eight atopic patients was studied using different concentrations of Fra a 1 isoforms. Bet v 1a was used as control and as atopic patient selection criterion. Although Fra a 1.01E-1.08 have amino acid sequence identities of 74.5-97.5% with Fra a 1.02, the basophil activation mediated by the eight Fra a 1 proteins differed substantially. Fra a 1.03 and Fra a 1.02 showed the highest activation of basophils, 73 and 66% of total basophils, respectively. On the basis of the high relative expression of the gene Fra a 1.02 in ripe strawberry fruits of allergenic varieties, Fra a 1.02 was identified as the main strawberry allergen of the Bet v 1 superfamily. Knowledge of the allergenic potential of Fra a 1.02/1.03 will help to improve food safety and can serve as a valuable marker for the development of red-fruited hypoallergenic strawberry cultivars.

  3. Nitrogen-doped hierarchical lamellar porous carbon synthesized from the fish scale as support material for platinum nanoparticle electrocatalyst toward the oxygen reduction reaction.

    PubMed

    Liu, Haijing; Cao, Yinliang; Wang, Feng; Huang, Yaqin

    2014-01-22

    Novel hierarchical lamellar porous carbon (HLPC) with high BET specific surface area of 2730 m(2) g(-1) and doped by nitrogen atoms has been synthesized from the fish scale without any post-synthesis treatment, and applied to support the platinum (Pt) nanoparticle (NP) catalysts (Pt/HLPC). The Pt NPs could be highly dispersed on the porous surface of HLPC with a narrow size distribution centered at ca. 2.0 nm. The results of the electrochemical analysis reveal that the electrochemical active surface area (ECSA) of Pt/HLPC is larger than the Pt NP electrocatalyst supported on the carbon black (Pt/Vulcan XC-72). Compared with the Pt/Vulcan XC-72, the Pt/HLPC exhibits larger current density, lower overpotential, and enhanced catalytic activity toward the oxygen reduction reaction (ORR) through the direct four-electron pathway. The improved catalytic activity is mainly attributed to the high BET specific surface area, hierarchical porous structures and the nitrogen-doped surface property of HLPC, indicating the superiority of HLPC as a promising support material for the ORR electrocatalysts.

  4. Towards real-time eruption forecasting in the Auckland Volcanic Field: application of BET_EF during the New Zealand National Disaster Exercise `Ruaumoko'

    NASA Astrophysics Data System (ADS)

    Lindsay, Jan; Marzocchi, Warner; Jolly, Gill; Constantinescu, Robert; Selva, Jacopo; Sandri, Laura

    2010-03-01

    The Auckland Volcanic Field (AVF) is a young basaltic field that lies beneath the urban area of Auckland, New Zealand’s largest city. Over the past 250,000 years the AVF has produced at least 49 basaltic centers; the last eruption was only 600 years ago. In recognition of the high risk associated with a possible future eruption in Auckland, the New Zealand government ran Exercise Ruaumoko in March 2008, a test of New Zealand’s nation-wide preparedness for responding to a major disaster resulting from a volcanic eruption in Auckland City. The exercise scenario was developed in secret, and covered the period of precursory activity up until the eruption. During Exercise Ruaumoko we adapted a recently developed statistical code for eruption forecasting, namely BET_EF (Bayesian Event Tree for Eruption Forecasting), to independently track the unrest evolution and to forecast the most likely onset time, location and style of the initial phase of the simulated eruption. The code was set up before the start of the exercise by entering reliable information on the past history of the AVF as well as the monitoring signals expected in the event of magmatic unrest and an impending eruption. The average probabilities calculated by BET_EF during Exercise Ruaumoko corresponded well to the probabilities subjectively (and independently) estimated by the advising scientists (differences of few percentage units), and provided a sound forecast of the timing (before the event, the eruption probability reached 90%) and location of the eruption. This application of BET_EF to a volcanic field that has experienced no historical activity and for which otherwise limited prior information is available shows its versatility and potential usefulness as a tool to aid decision-making for a wide range of volcano types. Our near real-time application of BET_EF during Exercise Ruaumoko highlighted its potential to clarify and possibly optimize decision-making procedures in a future AVF eruption

  5. The ATP-binding cassette transporter Cbc (choline/betaine/carnitine) recruits multiple substrate-binding proteins with strong specificity for distinct quaternary ammonium compounds

    PubMed Central

    Chen, Chiliang; Malek, Adel A.; Wargo, Matthew J.; Hogan, Deborah A.; Beattie, Gwyn A.

    2017-01-01

    Summary We identified a choline, betaine and carnitine transporter, designated Cbc, from Pseudomonas syringae and Pseudomonas aeruginosa that is unusual among members of the ATP-binding cassette (ABC) transporter family in its use of multiple periplasmic substrate-binding proteins (SBPs) that are highly specific for their substrates. The SBP encoded by the cbcXWV operon, CbcX, binds choline with a high affinity (Km, 2.6 μM) and, although it also binds betaine (Km, 24.2 μM), CbcXWV-mediated betaine uptake did not occur in the presence of choline. The CbcX orthologue ChoX from Sinorhizobium meliloti was similar to CbcX in these binding properties. The core transporter CbcWV also interacts with the carnitine-specific SBP CaiX (Km, 24 μM) and the betaine-specific SBP BetX (Km, 0.6 μM). Unlike most ABC transporter loci, caiX, betX and cbcXWV are separated in the genome. CaiX-mediated carnitine uptake was reduced by CbcX and BetX only when they were bound by their individual ligands, providing the first in vivo evidence for a higher affinity for ligand-bound than ligand-free SBPs by an ABC transporter. These studies demonstrate not only that the Cbc transporter serves as a useful model for exploring ABC transporter component interactions, but also that the orphan SBP genes common to bacterial genomes can encode functional SBPs. PMID:19919675

  6. The ATP-binding cassette transporter Cbc (choline/betaine/carnitine) recruits multiple substrate-binding proteins with strong specificity for distinct quaternary ammonium compounds.

    PubMed

    Chen, Chiliang; Malek, Adel A; Wargo, Matthew J; Hogan, Deborah A; Beattie, Gwyn A

    2010-01-01

    We identified a choline, betaine and carnitine transporter, designated Cbc, from Pseudomonas syringae and Pseudomonas aeruginosa that is unusual among members of the ATP-binding cassette (ABC) transporter family in its use of multiple periplasmic substrate-binding proteins (SBPs) that are highly specific for their substrates. The SBP encoded by the cbcXWV operon, CbcX, binds choline with a high affinity (K(m), 2.6 microM) and, although it also binds betaine (K(m), 24.2 microM), CbcXWV-mediated betaine uptake did not occur in the presence of choline. The CbcX orthologue ChoX from Sinorhizobium meliloti was similar to CbcX in these binding properties. The core transporter CbcWV also interacts with the carnitine-specific SBP CaiX (K(m), 24 microM) and the betaine-specific SBP BetX (K(m), 0.6 microM). Unlike most ABC transporter loci, caiX, betX and cbcXWV are separated in the genome. CaiX-mediated carnitine uptake was reduced by CbcX and BetX only when they were bound by their individual ligands, providing the first in vivo evidence for a higher affinity for ligand-bound than ligand-free SBPs by an ABC transporter. These studies demonstrate not only that the Cbc transporter serves as a useful model for exploring ABC transporter component interactions, but also that the orphan SBP genes common to bacterial genomes can encode functional SBPs.

  7. Well-temperate phage: Optimal bet-hedging against local environmental collapses

    DOE PAGES

    Maslov, Sergei; Sneppen, Kim

    2015-06-02

    Upon infection of their bacterial hosts temperate phages must chose between lysogenic and lytic developmental strategies. Here we apply the game-theoretic bet-hedging strategy introduced by Kelly to derive the optimal lysogenic fraction of the total population of phages as a function of frequency and intensity of environmental downturns affecting the lytic subpopulation. “Well-temperate” phage from our title is characterized by the best long-term population growth rate. We show that it is realized when the lysogenization frequency is approximately equal to the probability of lytic population collapse. We further predict the existence of sharp boundaries in system’s environmental, ecological, and biophysicalmore » parameters separating the regions where this temperate strategy is optimal from those dominated by purely virulent or dormant (purely lysogenic) strategies. We show that the virulent strategy works best for phages with large diversity of hosts, and access to multiple independent environments reachable by diffusion. Conversely, progressively more temperate or even dormant strategies are favored in the environments, that are subject to frequent and severe temporal downturns.« less

  8. Well-temperate phage: Optimal bet-hedging against local environmental collapses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maslov, Sergei; Sneppen, Kim

    Upon infection of their bacterial hosts temperate phages must chose between lysogenic and lytic developmental strategies. Here we apply the game-theoretic bet-hedging strategy introduced by Kelly to derive the optimal lysogenic fraction of the total population of phages as a function of frequency and intensity of environmental downturns affecting the lytic subpopulation. “Well-temperate” phage from our title is characterized by the best long-term population growth rate. We show that it is realized when the lysogenization frequency is approximately equal to the probability of lytic population collapse. We further predict the existence of sharp boundaries in system’s environmental, ecological, and biophysicalmore » parameters separating the regions where this temperate strategy is optimal from those dominated by purely virulent or dormant (purely lysogenic) strategies. We show that the virulent strategy works best for phages with large diversity of hosts, and access to multiple independent environments reachable by diffusion. Conversely, progressively more temperate or even dormant strategies are favored in the environments, that are subject to frequent and severe temporal downturns.« less

  9. Dectin-1 diversifies Aspergillus fumigatus–specific T cell responses by inhibiting T helper type 1 CD4 T cell differentiation

    PubMed Central

    Hohl, Tobias M.; Collins, Nichole; Leiner, Ingrid; Gallegos, Alena; Saijo, Shinobu; Coward, Jesse W.; Iwakura, Yoichiro

    2011-01-01

    Pulmonary infection of mice with Aspergillus fumigatus induces concurrent T helper type 1 (Th1) and Th17 responses that depend on Toll-like receptor/MyD88 and Dectin-1, respectively. However, the mechanisms balancing Th1 and Th17 CD4 T cell populations during infection remain incompletely defined. In this study, we show that Dectin-1 deficiency disproportionally increases Th1 responses and decreases Th17 differentiation after A. fumigatus infection. Dectin-1 signaling in A. fumigatus–infected wild-type mice reduces IFN-γ and IL-12p40 expression in the lung, thereby decreasing T-bet expression in responding CD4 T cells and enhancing Th17 responses. Absence of IFN-γ or IL-12p35 in infected mice or T-bet in responding CD4 T cells enhances Th17 differentiation, independent of Dectin-1 expression, in A. fumigatus–infected mice. Transient deletion of monocyte-derived dendritic cells also reduces Th1 and boosts Th17 differentiation of A. fumigatus–specific CD4 T cells. Our findings indicate that Dectin-1–mediated signals alter CD4 T cell responses to fungal infection by decreasing the production of IL-12 and IFN-γ in innate cells, thereby decreasing T-bet expression in A. fumigatus–specific CD4 T cells and enabling Th17 differentiation. PMID:21242294

  10. Crystallization of glass-forming liquids: Specific surface energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schmelzer, Jürn W. P., E-mail: juern-w.schmelzer@uni-rostock.de; Abyzov, Alexander S.

    2016-08-14

    A generalization of the Stefan-Skapski-Turnbull relation for the melt-crystal specific interfacial energy is developed in terms of the generalized Gibbs approach extending its standard formulation to thermodynamic non-equilibrium states. With respect to crystal nucleation, this relation is required in order to determine the parameters of the critical crystal clusters being a prerequisite for the computation of the work of critical cluster formation. As one of its consequences, a relation for the dependence of the specific surface energy of critical clusters on temperature and pressure is derived applicable for small and moderate deviations from liquid-crystal macroscopic equilibrium states. Employing the Stefan-Skapski-Turnbullmore » relation, general expressions for the size and the work of formation of critical crystal clusters are formulated. The resulting expressions are much more complex as compared to the respective relations obtained via the classical Gibbs theory. Latter relations are retained as limiting cases of these more general expressions for moderate undercoolings. By this reason, the formulated, here, general relations for the specification of the critical cluster size and the work of critical cluster formation give a key for an appropriate interpretation of a variety of crystallization phenomena occurring at large undercoolings which cannot be understood in terms of the Gibbs’ classical treatment.« less

  11. Race-specific molecular alterations correlate with differential outcomes for black and white endometrioid endometrial cancer patients.

    PubMed

    Bateman, Nicholas W; Dubil, Elizabeth A; Wang, Guisong; Hood, Brian L; Oliver, Julie M; Litzi, Tracy A; Gist, Glenn D; Mitchell, David A; Blanton, Brian; Phippen, Neil T; Tian, Chunqiao; Zahn, Christopher M; Cohn, David E; Havrilesky, Laura J; Berchuck, Andrew; Shriver, Craig D; Darcy, Kathleen M; Hamilton, Chad A; Conrads, Thomas P; Maxwell, G Larry

    2017-10-15

    The objective of this study was to identify molecular alterations associated with disease outcomes for white and black patients with endometrioid endometrial cancer (EEC). EEC samples from black (n = 17) and white patients (n = 13) were analyzed by proteomics (liquid chromatography-tandem mass spectrometry) and transcriptomics (RNA-seq). Coordinate alterations were validated with RNA-seq data from black (n = 49) and white patients (n = 216). Concordantly altered candidates were further tested for associations with race-specific progression-free survival (PFS) in black (n = 64) or white patients (n = 267) via univariate and multivariate Cox regression modeling and log-rank testing. Discovery analyses revealed significantly altered candidate proteins and transcripts between black and white patients, suggesting modulation of tumor cell viability in black patients and cell death signaling in black and white patients. Eighty-nine candidates were validated as altered between these patient cohorts, and a subset significantly correlated with differential PFS. White-specific PFS candidates included serpin family A member 4 (SERPINA4; hazard ratio [HR], 0.89; Wald P value = .02), integrin subunit α3 (ITGA3; HR, 0.76; P = .03), and Bet1 Golgi vesicular membrane trafficking protein like (BET1L; HR, 0.48; P = .04). Black-specific PFS candidates included family with sequence similarity 228 member B (FAM228B; HR, 0.13; P = .001) and HEAT repeat containing 6 (HEATR6; HR, 4.94; P = .047). Several candidates were also associated with overall survival (SERPINA4 and ITGA3) as well as PFS independent of disease stage, grade and myometrial invasion (SERPINA4, BET1L and FAM228B). This study has identified and validated molecular alterations in tumors from black and white EEC patients, including candidates significantly associated with altered disease outcomes within these patient cohorts. Cancer 2017;123:4004-12. © 2017 American Cancer Society. © 2017 American Cancer Society.

  12. Specific surface area of overlapping spheres in the presence of obstructions

    NASA Astrophysics Data System (ADS)

    Jenkins, D. R.

    2013-02-01

    This study considers the random placement of uniform sized spheres, which may overlap, in the presence of another set of randomly placed (hard) spheres, which do not overlap. The overlapping spheres do not intersect the hard spheres. It is shown that the specific surface area of the collection of overlapping spheres is affected by the hard spheres, such that there is a minimum in the specific surface area as a function of the relative size of the two sets of spheres. The occurrence of the minimum is explained in terms of the break-up of pore connectivity. The configuration can be considered to be a simple model of the structure of a porous composite material. In particular, the overlapping particles represent voids while the hard particles represent fillers. Example materials are pervious concrete, metallurgical coke, ice cream, and polymer composites. We also show how the material properties of such composites are affected by the void structure.

  13. Specific surface area of overlapping spheres in the presence of obstructions.

    PubMed

    Jenkins, D R

    2013-02-21

    This study considers the random placement of uniform sized spheres, which may overlap, in the presence of another set of randomly placed (hard) spheres, which do not overlap. The overlapping spheres do not intersect the hard spheres. It is shown that the specific surface area of the collection of overlapping spheres is affected by the hard spheres, such that there is a minimum in the specific surface area as a function of the relative size of the two sets of spheres. The occurrence of the minimum is explained in terms of the break-up of pore connectivity. The configuration can be considered to be a simple model of the structure of a porous composite material. In particular, the overlapping particles represent voids while the hard particles represent fillers. Example materials are pervious concrete, metallurgical coke, ice cream, and polymer composites. We also show how the material properties of such composites are affected by the void structure.

  14. Stable T-bet(+)GATA-3(+) Th1/Th2 hybrid cells arise in vivo, can develop directly from naive precursors, and limit immunopathologic inflammation.

    PubMed

    Peine, Michael; Rausch, Sebastian; Helmstetter, Caroline; Fröhlich, Anja; Hegazy, Ahmed N; Kühl, Anja A; Grevelding, Christoph G; Höfer, Thomas; Hartmann, Susanne; Löhning, Max

    2013-01-01

    Differentiated T helper (Th) cell lineages are thought to emerge from alternative cell fate decisions. However, recent studies indicated that differentiated Th cells can adopt mixed phenotypes during secondary immunological challenges. Here we show that natural primary immune responses against parasites generate bifunctional Th1 and Th2 hybrid cells that co-express the lineage-specifying transcription factors T-bet and GATA-3 and co-produce Th1 and Th2 cytokines. The integration of Th1-promoting interferon (IFN)-γ and interleukin (IL)-12 signals together with Th2-favoring IL-4 signals commits naive Th cells directly and homogeneously to the hybrid Th1/2 phenotype. Specifically, IFN-γ signals are essential for T-bet(+)GATA-3(+) cells to develop in vitro and in vivo by breaking the dominance of IL-4 over IL-12 signals. The hybrid Th1/2 phenotype is stably maintained in memory cells in vivo for months. It resists reprogramming into classic Th1 or Th2 cells by Th1- or Th2-promoting stimuli, which rather induce quantitative modulations of the combined Th1 and Th2 programs without abolishing either. The hybrid phenotype is associated with intermediate manifestations of both Th1 and Th2 cell properties. Consistently, hybrid Th1/2 cells support inflammatory type-1 and type-2 immune responses but cause less immunopathology than Th1 and Th2 cells, respectively. Thus, we propose the self-limitation of effector T cells based on the stable cell-intrinsic balance of two opposing differentiation programs as a novel concept of how the immune system can prevent excessive inflammation.

  15. Summertime evolution of snow specific surface area close to the surface on the Antarctic Plateau

    NASA Astrophysics Data System (ADS)

    Libois, Q.; Picard, G.; Arnaud, L.; Dumont, M.; Lafaysse, M.; Morin, S.; Lefebvre, E.

    2015-12-01

    On the Antarctic Plateau, snow specific surface area (SSA) close to the surface shows complex variations at daily to seasonal scales which affect the surface albedo and in turn the surface energy budget of the ice sheet. While snow metamorphism, precipitation and strong wind events are known to drive SSA variations, usually in opposite ways, their relative contributions remain unclear. Here, a comprehensive set of SSA observations at Dome C is analysed with respect to meteorological conditions to assess the respective roles of these factors. The results show an average 2-to-3-fold SSA decrease from October to February in the topmost 10 cm in response to the increase of air temperature and absorption of solar radiation in the snowpack during spring and summer. Surface SSA is also characterized by significant daily to weekly variations due to the deposition of small crystals with SSA up to 100 m2 kg-1 onto the surface during snowfall and blowing snow events. To complement these field observations, the detailed snowpack model Crocus is used to simulate SSA, with the intent to further investigate the previously found correlation between interannual variability of summer SSA decrease and summer precipitation amount. To this end, some Crocus parameterizations have been adapted to Dome C conditions, and the model was forced by ERA-Interim reanalysis. It successfully matches the observations at daily to seasonal timescales, except for the few cases when snowfalls are not captured by the reanalysis. On the contrary, the interannual variability of summer SSA decrease is poorly simulated when compared to 14 years of microwave satellite data sensitive to the near-surface SSA. A simulation with disabled summer precipitation confirms the weak influence in the model of the precipitation on metamorphism, with only 6 % enhancement. However, we found that disabling strong wind events in the model is sufficient to reconciliate the simulations with the observations. This suggests that

  16. Summertime evolution of snow specific surface area close to the surface on the Antarctic Plateau

    NASA Astrophysics Data System (ADS)

    Libois, Q.; Picard, G.; Arnaud, L.; Dumont, M.; Lafaysse, M.; Morin, S.; Lefebvre, E.

    2015-08-01

    On the Antarctic Plateau, snow specific surface area (SSA) close to the surface shows complex variations at daily to seasonal scales which affect the surface albedo and in turn the surface energy budget of the ice sheet. While snow metamorphism, precipitation and strong wind events are known to drive SSA variations, usually in opposite ways, their relative contributions remain unclear. Here, a comprehensive set of SSA observations at Dome C is analysed with respect to meteorological conditions to assess the respective roles of these factors. The results show an average two-to-three-fold SSA decrease from October to February in the topmost 10 cm, in response to the increase of air temperature and absorption of solar radiation in the snowpack during spring and summer. Surface SSA is also characterised by significant daily to weekly variations, due to the deposition of small crystals with SSA up to 100 m2 kg-1 onto the surface during snowfall and blowing snow events. To complement these field observations, the detailed snowpack model Crocus is used to simulate SSA, with the intent to further investigate the previously found correlation between inter-annual variability of summer SSA decrease and summer precipitation amount. To this end, Crocus parameterizations have been adapted to Dome C conditions, and the model was forced by ERA-Interim reanalysis. It successfully matches the observations at daily to seasonal time scales, except for few cases when snowfalls are not captured by the reanalysis. On the contrary, the inter-annual variability of summer SSA decrease is poorly simulated when compared to 14 years of microwave satellite data sensititve to the near surface SSA. A simulation with disabled summer precipitation confirms the weak influence in the model of the precipitation on metamorphism, with only 6 % enhancement. However we found that disabling strong wind events in the model is sufficient to reconciliate the simulations with the observations. This suggests

  17. Environmental and genetic sources of diversification in the timing of seed germination: implications for the evolution of bet hedging.

    PubMed

    Simons, Andrew M; Johnston, Mark O

    2006-11-01

    Environmental variation that is not predictably related to cues is expected to drive the evolution of bet-hedging strategies. The high variance observed in the timing of seed germination has led to it being the most cited diversification strategy in the theoretical bet-hedging literature. Despite this theoretical focus, virtually nothing is known about the mechanisms responsible for the generation of individual-level diversification. Here we report analyses of sources of variation in timing of germination within seasons, germination fraction over two generations and three sequential seasons, and the genetic correlation structure of these traits using almost 10,000 seeds from more than 100 genotypes of the monocarpic perennial Lobelia inflata. Microenvironmental analysis of time to germination suggests that extreme sensitivity to environmental gradients, or microplasticity, even within a homogeneous growth chamber, may act as an effective individual-level diversification mechanism and explains more than 30% of variance in time to germination. The heritability of within-season timing of germination was low (h(2) = 0.07) but significant under homogeneous conditions. Consistent with individual-level diversification, this low h(2) was attributable not to low additive genetic variance, but to an unusually high coefficient of residual variation in time to germination. Despite high power to detect additive genetic variance in within-season diversification, it was low and indistinguishable from zero. Restricted maximum likelihood detected significant genetic variation for germination fraction (h(2) = 0.18) under homogeneous conditions. Unexpectedly, this heritability was positive when measured within a generation by sibling analysis and negative when measured across generations by offspring-on-parent regression. The consistency of dormancy fraction over multiple delays, a major premise of Cohen's classic model, was supported by a strong genetic correlation (r = 0

  18. T-bet-dependent NKp46+ innate lymphoid cells regulate the onset of TH17-induced neuroinflammation. | Center for Cancer Research

    Cancer.gov

    The process by which self-reactive CD4+ T cells infiltrate the central nervous system (CNS) and trigger neuroinflammation is not fully understood. Lazarevic and colleagues show that NKp46+innate lymphoid cells dependent on the transcription factor T-bet are critical mediators in facilitating the entry of autoreactive CD4+ cells of the TH17 subset of helper T cells into the

  19. Surface acid-base properties and hydration/dehydration mechanisms of aluminum (hydr)oxides.

    PubMed

    Yang, Xiaofang; Sun, Zhongxi; Wang, Dongsheng; Forsling, Willis

    2007-04-15

    In this paper, surface physiochemical properties of three typical aluminas, gamma-Al(OH)3, gamma-Al2O3, and alpha-Al2O3, were investigated by means of XRD, SEM, TEM, BET surface area, TG/DTA, and potentiometric titration techniques. Based on the titration data, surface protonation and deprotonation constants were determined using the constant capacitance model (CCM). The emphasis of this research was laid on the comparison of the crystal structure, surface hydration/dehydration and acid-base properties of these three typical alumina minerals. The calculation results revealed that the surface acidity of the aluminas is in the order of alpha-Al2O3>gamma-Al(OH)3>gamma-Al2O3 after being hydrated for 1 h. The correlation between the hydration/dehydration mechanisms of alumina and its acid/base properties is discussed.

  20. Landsat Collection 1 Data: Assessing the Impacts of Surface Reflectance Product Changes on an Operational Rangeland Management Tool

    NASA Astrophysics Data System (ADS)

    Holifield Collins, C.; Skirvin, S. M.; Kautz, M. A.; Metz, L. J.

    2017-12-01

    The Landsat Surface Reflectance (SR) Product is valuable for applied research of the Earth's surface and has been used in the development of a number of operational products. Landsat SR data available as of April 2017 have been processed through a new system and are publically available as part of a new product set known as Collection 1. The impact of these changes has not yet been described, but knowing their nature and magnitude is vital for continued confidence in operational products produced from these datasets. The Rangeland Brush Estimation Toolbox (RaBET) developed for USDA Natural Resources Conservation Service (NRCS) land managers is based on relationships developed using the pre-April 2017 Landsat SR Product to derive estimates of woody cover in western rangelands. The maps produced from this tool will be used to aid in planning the implementation of brush removal treatments. Due to the vast expenditure of resources (millions of dollars per year) required to execute these treatments, it is imperative that the effects of the SR data processing changes are understood to allow for modifications in the tool if necessary. The objectives of this study are to: 1) determine where SR data processing changes have the greatest effect on the Landsat-based vegetation indices used within RaBET for Major Land Resource Areas (MLRAs) in Arizona and Texas, and 2) compare model outputs arising from Landsat SR data obtained pre- and post- April 2017 to assess the magnitude of the changes to the RaBET end product.

  1. Effect of degassing temperature on specific surface area and pore volume measurements of biochar

    NASA Astrophysics Data System (ADS)

    Sigmund, Gabriel; Hüffer, Thorsten; Kah, Melanie; Hofmann, Thilo

    2017-04-01

    Specific surface area, pore volume, and pore size distribution are key biochar properties that have been related to water and nutrient cycling, microbial activity as well as sorption potential for organic compounds. Specific surface area and pore volume are commonly determined by measurement of physisorption of N2 and/or CO2. The measurement requires prior degassing of the samples, which may change the structure of the materials. Information on degassing temperature is rarely reported in literature, and recommendations differ considerably between existing guidelines for biochar characterization. Therefore, the influence of degassing temperature on N2 and CO2physisorption measurements was investigated by systematically degassing a range of materials, including four biochars, Al2O3 and carbon nanotubes at different temperatures (105 ˚ C, 150 ˚ C, 200 ˚ C, 250 ˚ C and 300 ˚ C for ≥ 14 h each). Measured specific surface area and pore volume increased with increasing degassing temperature for all biochars. Additional surface area and pore volume may have become available as components in biochars volatilized during the degassing phase. The results of our study showed that (i) degassing conditions change material properties, and influence physisorption measurements for biochar (ii) comparison between parameters derived from different degassing protocols may not be appropriate, and (iii) degassing protocols should be harmonized in the biochar community [1]. [1] Sigmund, et al. (2016), "Biochar total surface area and total pore volume determined by N2 and CO2 physisorption are strongly influenced by degassing temperature", STOTEN, doi: http://dx.doi.org/10.1016/j.scitotenv.2016.12.023.

  2. Tuning the relative concentration ratio of bulk defects to surface defects in TiO2 nanocrystals leads to high photocatalytic efficiency.

    PubMed

    Kong, Ming; Li, Yuanzhi; Chen, Xiong; Tian, Tingting; Fang, Pengfei; Zheng, Feng; Zhao, Xiujian

    2011-10-19

    TiO(2) nanocrystals with tunable bulk/surface defects were synthesized and characterized with TEM, XRD, BET, positron annihilation, and photocurrent measurements. The effect of defects on photocatalytic activity was studied. It was found for the first time that decreasing the relative concentration ratio of bulk defects to surface defects in TiO(2) nanocrystals could significantly improve the separation efficiency of photogenerated electrons and holes, thus significantly enhancing the photocatalytic efficiency.

  3. Correlation of Gear Surface Fatigue Lives to Lambda Ratio (Specific Film Thickness)

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy Lewis

    2013-01-01

    The effect of the lubrication regime on gear performance has been recognized, qualitatively, for decades. Often the lubrication regime is characterized by the specific film thickness being the ratio of lubricant film thickness to the composite surface roughness. Three studies done at NASA to investigate gearing pitting life are revisited in this work. All tests were done at a common load. In one study, ground gears were tested using a variety of lubricants that included a range of viscosities, and therefore the gears operated with differing film thicknesses. In a second and third study, the performance of gears with ground teeth and superfinished teeth were assessed. Thicker oil films provided longer lives as did improved surface finish. These datasets were combined into a common dataset using the concept of specific film thickness. This unique dataset of more 258 tests provides gear designers with some qualitative information to make gear design decisions.

  4. [Adsorption of Cu on Core-shell Structured Magnetic Particles: Relationship Between Adsorption Performance and Surface Properties].

    PubMed

    Li, Qiu-mei; Chen, Jing; Li, Hai-ning; Zhang, Xiao-lei; Zhang, Gao-sheng

    2015-12-01

    In order to reveal the relationship between the adsorption performance of adsorbents and their compositions, structure, and surface properties, the core-shell structured Fe₃O₄/MnO2 and Fe-Mn/Mn₂2 magnetic particles were systematically characterized using multiple techniques and their Cu adsorption behaviors as well as mechanism were also investigated in details. It was found that both Fe₃O4 and Fe-Mn had spinel structure and no obvious crystalline phase change was observed after coating with MnO₂. The introduction of Mn might improve the affinity between the core and the shell, and therefore enhanced the amount and distribution uniformity of the MnO₂ coated. Consequently, Fe-Mn/MnO₂ exhibited a higher BET specific surface area and a lower isoelectric point. The results of sorption experiments showed that Fe-Mn had a higher maximal Cu adsorption capacity of 33.7 mg · g⁻¹ at pH 5.5, compared with 17.5 mg · g⁻¹ of Fe₃O4. After coating, the maximal adsorption capacity of Fe-Mn/MnO₂ was increased to 58.2 mg · g⁻¹, which was 2.6 times as high as that of Fe₃O₄/MnO₂ and outperformed the majority of magnetic adsorbents reported in literature. In addition, a specific adsorption of Cu occurred at the surface of Fe₃O₄/MnO₂ or Fe-Mn/MnO₂ through the formation of inner-sphere complexes. In conclusion, the adsorption performance of the magnetic particles was positively related to their compositions, structure, and surface properties.

  5. Biotransformation of Momordica charantia fresh juice by Lactobacillus plantarum BET003 and its putative anti-diabetic potential.

    PubMed

    Mazlan, Farhaneen Afzal; Annuar, M Suffian M; Sharifuddin, Yusrizam

    2015-01-01

    Lactobacillus plantarum BET003 isolated from Momordica charantia fruit was used to ferment its juice. Momordica charantia fresh juice was able to support good growth of the lactic acid bacterium. High growth rate and cell viability were obtained without further nutrient supplementation. In stirred tank reactor batch fermentation, agitation rate showed significant effect on specific growth rate of the bacterium in the fruit juice. After the fermentation, initially abundant momordicoside 23-O-β-Allopyranosyle-cucurbita-5,24-dien-7α,3β,22(R),23(S)-tetraol-3-O-β-allopyranoside was transformed into its corresponding aglycone in addition to the emergence of new metabolites. The fermented M. charantia juice consistently reduced glucose production by 27.2%, 14.5%, 17.1% and 19.2% at 15-minute intervals respectively, when compared against the negative control. This putative anti-diabetic activity can be attributed to the increase in availability and concentration of aglycones as well as other phenolic compounds resulting from degradation of glycosidic momordicoside. Biotransformation of M. charantia fruit juice via lactic acid bacterium fermentation reduced its bitterness, reduced its sugar content, produced aglycones and other metabolites as well as improved its inhibition of α-glucosidase activity compared with the fresh, non-fermented juice.

  6. Biotransformation of Momordica charantia fresh juice by Lactobacillus plantarum BET003 and its putative anti-diabetic potential

    PubMed Central

    Mazlan, Farhaneen Afzal; Annuar, M. Suffian M.

    2015-01-01

    Lactobacillus plantarum BET003 isolated from Momordica charantia fruit was used to ferment its juice. Momordica charantia fresh juice was able to support good growth of the lactic acid bacterium. High growth rate and cell viability were obtained without further nutrient supplementation. In stirred tank reactor batch fermentation, agitation rate showed significant effect on specific growth rate of the bacterium in the fruit juice. After the fermentation, initially abundant momordicoside 23-O-β-Allopyranosyle-cucurbita-5,24-dien-7α,3β,22(R),23(S)-tetraol-3-O-β-allopyranoside was transformed into its corresponding aglycone in addition to the emergence of new metabolites. The fermented M. charantia juice consistently reduced glucose production by 27.2%, 14.5%, 17.1% and 19.2% at 15-minute intervals respectively, when compared against the negative control. This putative anti-diabetic activity can be attributed to the increase in availability and concentration of aglycones as well as other phenolic compounds resulting from degradation of glycosidic momordicoside. Biotransformation of M. charantia fruit juice via lactic acid bacterium fermentation reduced its bitterness, reduced its sugar content, produced aglycones and other metabolites as well as improved its inhibition of α-glucosidase activity compared with the fresh, non-fermented juice. PMID:26539336

  7. A quantitative method to discriminate between non-specific and specific lectin-glycan interactions on silicon-modified surfaces.

    PubMed

    Yang, Jie; Siriwardena, Aloysius; Boukherroub, Rabah; Ozanam, François; Szunerits, Sabine; Gouget-Laemmel, Anne Chantal

    2016-02-15

    Essential to the success of any surface-based carbohydrate biochip technology is that interactions of the particular interface with the target protein be reliable and reproducible and not susceptible to unwanted nonspecific adsorption events. This condition is particularly important when the technology is intended for the evaluation of low-affinity interactions such as those typically encountered between lectins and their monomeric glycan ligands. In this paper, we describe the fabrication of glycan (mannoside and lactoside) monolayers immobilized on hydrogenated crystalline silicon (111) surfaces. An efficient conjugation protocol featuring a key "click"-based coupling step has been developed which ensures the obtention of interfaces with controlled glycan density. The adsorption behavior of these newly developed interfaces with the lectins, Lens culinaris and Peanut agglutinin, has been probed using quantitative IR-ATR and the data interpreted using various isothermal models. The analysis reveals that protein physisorption to the interface is more prevalent than specific chemisorption for the majority of washing protocols investigated. Physisorption can be greatly suppressed through application of a strong surfactinated rinse. The coexistence of chemisorption and physisorption processes is further demonstrated by quantification of the amounts of adsorbed proteins distributed on the surface, in correlation with the results obtained by atomic force microscopy (AFM). Taken together, the data demonstrates that the nonspecific adsorption of proteins to these glycan-terminated surfaces can be effectively eliminated through the proper control of the chemical structure of the surface monolayer combined with the implementation of an appropriate surface-rinse protocol. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Human milk containing specific secretory IgA inhibits binding of Giardia lamblia to nylon and glass surfaces.

    PubMed

    Samra, H K; Ganguly, N K; Mahajan, R C

    1991-06-01

    The effects of human milk, containing specific secretory IgA, on the adherence of Giardia lamblia trophozoites in the presence and in the absence of intestinal mucus in vitro were studied. It was found that the trophozoites treated with breast milk, containing specific secretory IgA to G. lamblia, showed a significant decrease (p less than 0.01) in adherence to nylon fibre columns and glass surfaces than did trophozoites treated with milk containing no SIgA antibodies. The adherence to glass surfaces was significantly more (p less than 0.01) in the presence of intestinal mucus than when the mucus was absent. Milk that did not contain specific secretory SIgA to G. lamblia did not decrease the adherence to glass surfaces either in the presence or in the absence of mucus. The fluorescence study revealed the binding of specific secretory IgA on the trophozoite surface. The results suggest that binding of SIgA antibodies in milk to G. lamblia trophozoites inhibits parasite adherence, thus protecting against this infection in breast-fed babies.

  9. Hydration Repulsion between Carbohydrate Surfaces Mediated by Temperature and Specific Ions

    PubMed Central

    Chen, Hsieh; Cox, Jason R.; Ow, Hooisweng; Shi, Rena; Panagiotopoulos, Athanassios Z.

    2016-01-01

    Stabilizing colloids or nanoparticles in solution involves a fine balance between surface charges, steric repulsion of coating molecules, and hydration forces against van der Waals attractions. At high temperature and electrolyte concentrations, the colloidal stability of suspensions usually decreases rapidly. Here, we report a new experimental and simulation discovery that the polysaccharide (dextran) coated nanoparticles show ion-specific colloidal stability at high temperature, where we observed enhanced colloidal stability of nanoparticles in CaCl2 solution but rapid nanoparticle-nanoparticle aggregation in MgCl2 solution. The microscopic mechanism was unveiled in atomistic simulations. The presence of surface bound Ca2+ ions increases the carbohydrate hydration and induces strongly polarized repulsive water structures beyond at least three hydration shells which is farther-reaching than previously assumed. We believe leveraging the binding of strongly hydrated ions to macromolecular surfaces represents a new paradigm in achieving absolute hydration and colloidal stability for a variety of materials, particularly under extreme conditions. PMID:27334145

  10. Hydration Repulsion between Carbohydrate Surfaces Mediated by Temperature and Specific Ions

    NASA Astrophysics Data System (ADS)

    Chen, Hsieh; Cox, Jason R.; Ow, Hooisweng; Shi, Rena; Panagiotopoulos, Athanassios Z.

    2016-06-01

    Stabilizing colloids or nanoparticles in solution involves a fine balance between surface charges, steric repulsion of coating molecules, and hydration forces against van der Waals attractions. At high temperature and electrolyte concentrations, the colloidal stability of suspensions usually decreases rapidly. Here, we report a new experimental and simulation discovery that the polysaccharide (dextran) coated nanoparticles show ion-specific colloidal stability at high temperature, where we observed enhanced colloidal stability of nanoparticles in CaCl2 solution but rapid nanoparticle-nanoparticle aggregation in MgCl2 solution. The microscopic mechanism was unveiled in atomistic simulations. The presence of surface bound Ca2+ ions increases the carbohydrate hydration and induces strongly polarized repulsive water structures beyond at least three hydration shells which is farther-reaching than previously assumed. We believe leveraging the binding of strongly hydrated ions to macromolecular surfaces represents a new paradigm in achieving absolute hydration and colloidal stability for a variety of materials, particularly under extreme conditions.

  11. Tuning the Pore Geometry of Ordered Mesoporous Carbons for Enhanced Adsorption of Bisphenol-A

    PubMed Central

    Libbrecht, Wannes; Vandaele, Koen; De Buysser, Klaartje; Verberckmoes, An; Thybaut, Joris W.; Poelman, Hilde; De Clercq, Jeriffa; Van Der Voort, Pascal

    2015-01-01

    Mesoporous carbons were synthesized via both soft and hard template methods and compared to a commercial powder activated carbon (PAC) for the adsorption ability of bisphenol-A (BPA) from an aqueous solution. The commercial PAC had a BET-surface of 1027 m2/g with fine pores of 3 nm and less. The hard templated carbon (CMK-3) material had an even higher BET-surface of 1420 m2/g with an average pore size of 4 nm. The soft templated carbon (SMC) reached a BET-surface of 476 m2/g and a pore size of 7 nm. The maximum observed adsorption capacity (qmax) of CMK-3 was the highest with 474 mg/g, compared to 290 mg/g for PAC and 154 mg/g for SMC. The difference in adsorption capacities was attributed to the specific surface area and hydrophobicity of the adsorbent. The microporous PAC showed the slowest adsorption, while the ordered mesopores of SMC and CMK-3 enhanced the BPA diffusion into the adsorbent. This difference in adsorption kinetics is caused by the increase in pore diameter. However, CMK-3 with an open geometry consisting of interlinked nanorods allows for even faster intraparticle diffusion. PMID:28788023

  12. Clinical Remission of Sight-Threatening Non-Infectious Uveitis Is Characterized by an Upregulation of Peripheral T-Regulatory Cell Polarized Towards T-bet and TIGIT.

    PubMed

    Gilbert, Rose M; Zhang, Xiaozhe; Sampson, Robert D; Ehrenstein, Michael R; Nguyen, Dao X; Chaudhry, Mahid; Mein, Charles; Mahmud, Nadiya; Galatowicz, Grazyna; Tomkins-Netzer, Oren; Calder, Virginia L; Lightman, Sue

    2018-01-01

    Non-infectious uveitis can cause chronic relapsing and remitting ocular inflammation, which may require high dose systemic immunosuppression to prevent severe sight loss. It has been classically described as an autoimmune disease, mediated by pro-inflammatory Th1 and Th17 T-cell subsets. Studies suggest that natural immunosuppressive CD4 + CD25 + FoxP3 + T-regulatory cells (Tregs) are involved in resolution of inflammation and may be involved in the maintenance of clinical remission. To investigate whether there is a peripheral blood immunoregulatory phenotype associated with clinical remission of sight-threatening non-infectious uveitis by comparing peripheral blood levels of Treg, Th1, and Th17, and associated DNA methylation and cytokine levels in patients with active uveitic disease, control subjects and patients (with previously active disease) in clinical remission induced by immunosuppressive drugs. Isolated peripheral blood mononuclear cells (PBMC) from peripheral blood samples from prospectively recruited subjects were analyzed by flow cytometry for CD3, CD4, FoxP3, TIGIT, T-bet, and related orphan receptor γt. Epigenetic DNA methylation levels of FOXP3 Treg-specific demethylated region (TSDR), FOXP3 promoter, TBX21, RORC2, and TIGIT loci were determined in cryopreserved PBMC using a next-generation sequencing approach. Related cytokines were measured in blood sera. Functional suppressive capacity of Treg was assessed using T-cell proliferation assays. Fifty patients with uveitis (intermediate, posterior, and panuveitis) and 10 control subjects were recruited. The frequency of CD4 + CD25 + FoxP3 + Treg, TIGIT + Treg, and T-bet + Treg and the ratio of Treg to Th1 were significantly higher in remission patients compared with patients with active uveitic disease; and TIGIT + Tregs were a significant predictor of clinical remission. Treg from patients in clinical remission demonstrated a high level of in vitro suppressive function compared with Treg from

  13. Outer-sphere Pb(II) adsorbed at specific surface sites on single crystal α-alumina

    USGS Publications Warehouse

    Bargar, John R.; Towle, Steven N.; Brown, Gordon E.; Parks, George A.

    1996-01-01

    Solvated Pb(II) ions were found to adsorb as structurally well-defined outer-sphere complexes at specific sites on the α-Al2O3 (0001) single crystal surface, as determined by grazing-incidence X-ray absorption fine structure (GI-XAFS) measurements. The XAFS results suggest that the distance between Pb(II) adions and the alumina surface is approximately 4.2 Å. In contrast, Pb(II) adsorbs as more strongly bound inner-sphere complexes on α-Al2O3 (102). The difference in reactivities of the two alumina surfaces has implications for modeling surface complexation reactions of contaminants in natural environments, catalysis, and compositional sector zoning of oxide crystals.

  14. Increasing the Detection Limit of the Parkinson Disorder through a Specific Surface Chemistry Applied onto Inner Surface of the Titration Well.

    PubMed

    Mille, Caroline; Debarnot, Dominique; Zorzi, Willy; El Moualij, Benaïssa; Coudreuse, Arnaud; Legeay, Gilbert; Quadrio, Isabelle; Perret-Liaudet, Armand; Poncin-Epaillard, Fabienne

    2012-04-18

    The main objective of this paper was to illustrate the enhancement of the sensitivity of ELISA titration for neurodegenerative proteins by reducing nonspecific adsorptions that could lead to false positives. This goal was obtained thanks to the association of plasma and wet chemistries applied to the inner surface of the titration well. The polypropylene surface was plasma-activated and then, dip-coated with different amphiphilic molecules. These molecules have more or less long hydrocarbon chains and may be charged. The modified surfaces were characterized in terms of hydrophilic-phobic character, surface chemical groups and topography. Finally, the coated wells were tested during the ELISA titration of the specific antibody capture of the α-synuclein protein. The highest sensitivity is obtained with polar (Θ = 35°), negatively charged and smooth inner surface.

  15. Increasing the Detection Limit of the Parkinson Disorder through a Specific Surface Chemistry Applied onto Inner Surface of the Titration Well

    PubMed Central

    Mille, Caroline; Debarnot, Dominique; Zorzi, Willy; Moualij, Benaïssa El; Coudreuse, Arnaud; Legeay, Gilbert; Quadrio, Isabelle; Perret-Liaudet, Armand; Poncin-Epaillard, Fabienne

    2012-01-01

    The main objective of this paper was to illustrate the enhancement of the sensitivity of ELISA titration for neurodegenerative proteins by reducing nonspecific adsorptions that could lead to false positives. This goal was obtained thanks to the association of plasma and wet chemistries applied to the inner surface of the titration well. The polypropylene surface was plasma-activated and then, dip-coated with different amphiphilic molecules. These molecules have more or less long hydrocarbon chains and may be charged. The modified surfaces were characterized in terms of hydrophilic—phobic character, surface chemical groups and topography. Finally, the coated wells were tested during the ELISA titration of the specific antibody capture of the α-synuclein protein. The highest sensitivity is obtained with polar (Θ = 35°), negatively charged and smooth inner surface. PMID:24955533

  16. Polyaniline nanofibers with a high specific surface area and an improved pore structure for supercapacitors

    NASA Astrophysics Data System (ADS)

    Xu, Hailing; Li, Xingwei; Wang, Gengchao

    2015-10-01

    Polyaniline (PANI) with a high specific surface area and an improved pore structure (HSSA-PANI) has been prepared by using a facile method, treating PANI nanofibers with chloroform (CHCl3), and its structure, morphology and pore structure are investigated. The specific surface area and pore volume of HSSA-PANI are 817.3 m2 g-1 and 0.6 cm3 g-1, and those of PANI are 33.6 m2 g-1 and 0.2 cm3 g-1. As electrode materials, a large specific surface area and pore volume can provide high electroactive regions, accelerate the diffusion of ions, and mitigate the electrochemical degradation of active materials. Compared with PANI, the capacity retention rate of HSSA-PANI is 90% with a growth of current density from 5.0 to 30 A g-1, and that of PANI is 29%. At a current density of 30 A g-1, the specific capacitance of HSSA-PANI still reaches 278.3 F g-1, and that of PANI is 86.7 F g-1. At a current density of 5.0 A g-1, the capacitance retention of HSSA-PANI is 53.1% after 2000 cycles, and that of PANI electrode is only 28.1%.

  17. An automatic rat brain extraction method based on a deformable surface model.

    PubMed

    Li, Jiehua; Liu, Xiaofeng; Zhuo, Jiachen; Gullapalli, Rao P; Zara, Jason M

    2013-08-15

    The extraction of the brain from the skull in medical images is a necessary first step before image registration or segmentation. While pre-clinical MR imaging studies on small animals, such as rats, are increasing, fully automatic imaging processing techniques specific to small animal studies remain lacking. In this paper, we present an automatic rat brain extraction method, the Rat Brain Deformable model method (RBD), which adapts the popular human brain extraction tool (BET) through the incorporation of information on the brain geometry and MR image characteristics of the rat brain. The robustness of the method was demonstrated on T2-weighted MR images of 64 rats and compared with other brain extraction methods (BET, PCNN, PCNN-3D). The results demonstrate that RBD reliably extracts the rat brain with high accuracy (>92% volume overlap) and is robust against signal inhomogeneity in the images. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. In-use catalyst surface area and its relation to HC conversion efficiency and FTP emissions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Donahue, K.S.; Sabourin, M.A.; Larson, R.E.

    1986-01-01

    Surface area data, steady-state hydrocarbon conversion efficiency data, and hydrocarbon emissions results have been determined for catalysts collected by the U.S. Environmental Protection Agency from properly maintained 1981 and 1982 model year vehicles. Catalysts covered in this study were limited to those with three-way-plus-oxidation monolith technologies. Catalyst surface areas were measured using the BET method, conversion efficiencies were measured on an exhaust gas generator, and emissions results were determined using the Urban Driving Schedule of the Federal Test Procedure. Results indicate that correlation of catalyst surface area data with hydrocarbon conversion efficiency data and hydrocarbon emissions results is significant formore » the sample studied.« less

  19. Motility assays using myosin attached to surfaces through specific binding to monoclonal antibodies.

    PubMed Central

    Winkelmann, D. A.; Bourdieu, L.; Kinose, F.; Libchaber, A.

    1995-01-01

    We have analyzed the dependence of actin filament movement on the mode of myosin attachment to surfaces. Monoclonal antibodies that bind to three distinct sites were used to tether myosin to nitrocellulose-coated glass. One antibody reacts with an epitope on the regulatory light chain located at the head-rod junction. The other two react with sites in the rod domain, one in the S2 region near the S2-LMM hinge, and the other at the C terminus of the myosin rod. These monoclonal antibodies were used to provide increasing flexibility in the mode of attachment. Fast skeletal muscle myosin monomers were bound to the surfaces through the specific interaction with these monoclonal antibodies and the sliding movement of fluorescently labeled actin filaments analyzed by video microscopy. Each of these antibodies produced stable, myosin-coated surfaces that supported uniform movement of actin over the course of several hours. Attachment of myosin through the anti-S2 and anti-LMM monoclonal antibodies yielded a maximum velocity of 10 microns/s at 30 degrees C, whereas attachment through anti-LC2 produced a lower velocity of 4-5 microns/s. Each antibody showed a characteristic minimum myosin density below which sliding movement was no longer supported and an exponential dependence of actin filament velocity on myosin surface density below Vmax. Maximum sliding velocity was achieved over a range of myosin surface densities. Thus, the specific mode of attachment can influence the characteristic velocity of actin filament movement and the surface density needed to support movement. These data are being used to analyze the dynamics of sliding filament assays and evaluate estimates of the average number of motor molecules per unit length of actin required to support movement. PMID:7787107

  20. Renovation And Adaptation Of The Historic Olsztyn Purification House Bet Tahara Into A Public Utility Building

    NASA Astrophysics Data System (ADS)

    Deja, Barbara Maria

    2015-09-01

    The historic Jewish Purification House Bet Tahara was erected in Olsztyn in 1913 on the basis of the debut design of Erich Mendelsohn, a world-famous architect born in Olsztyn. The most valuable element of the building is a self-supporting pyramid vault above a mourning hall. The paper presents the interesting structure of the building, its technical condition before renovation, as well as the scope of work involved in adapting it into a public utility building - MENDELSOHN HOUSE Intercultural Dialogue Centre. The undertaking was executed thanks to the commitment of the building's leaseholder - "Borussia" Cultural Community Association, which raised money for this goal from public funds.

  1. Ambient pressure dried tetrapropoxysilane-based silica aerogels with high specific surface area

    NASA Astrophysics Data System (ADS)

    Parale, Vinayak G.; Han, Wooje; Jung, Hae-Noo-Ree; Lee, Kyu-Yeon; Park, Hyung-Ho

    2018-01-01

    In the present paper, we report the synthesis of tetrapropoxysilane (TPOS)-based silica aerogels with high surface area and large pore volume. The silica aerogels were prepared by a two-step sol-gel process followed by surface modification via a simple ambient pressure drying approach. In order to minimize drying shrinkage and obtain hydrophobic aerogels, the surface of the alcogels was modified using trichloromethylsilane as a silylating agent. The effect of the sol-gel compositional parameters on the polymerization of aerogels prepared by TPOS, one of the precursors belonging to the Si(OR)4 family, was reported for the first time. The oxalic acid and NH4OH concentrations were adjusted to achieve good-quality aerogels with high surface area, low density, and high transparency. Controlling the hydrolysis and condensation reactions of the TPOS precursor turned out to be the most important factor to determine the pore characteristics of the aerogel. Highly transparent aerogels with high specific surface area (938 m2/g) and low density (0.047 g/cm3) could be obtained using an optimized TPOS/MeOH molar ratio with appropriate concentrations of oxalic acid and NH4OH.

  2. Microstructure and thermal conductivity of surfactant-free NiO nanostructures

    NASA Astrophysics Data System (ADS)

    Sahoo, Pranati; Misra, Dinesh K.; Salvador, Jim; Makongo, Julien P. A.; Chaubey, Girija S.; Takas, Nathan J.; Wiley, John B.; Poudeu, Pierre F. P.

    2012-06-01

    High purity, nanometer sized surfactant-free nickel oxide (NiO) particles were produced in gram scale using a solution combustion method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), gas pycnometry and gas adsorption analysis (BET). The average particle size of the as-synthesized NiO increases significantly with the preheating temperature of the furnace, while the specific surface area decreases. A BET specific surface area of ∼100 m2/g was obtained for NiO nanoparticles with size as small as 3 nm synthesized at 300 °C. The thermal conductivity (κ) of pressed pellets of the synthesized NiO nanoparticles obtained using spark plasma sintering (SPS) and uniaxial hot pressing is drastically decreased (∼60%) compared to that of NiO single crystal. This strong reduction in κ with particle size suggests the suitability of the synthesized surfactant-free NiO nanoparticles for use as nanoinclusions when designing high performance materials for waste heat recovery.

  3. Onion-derived N, S self-doped carbon materials as highly efficient metal-free electrocatalysts for the oxygen reduction reaction

    NASA Astrophysics Data System (ADS)

    Yang, Shuting; Mao, Xinxin; Cao, Zhaoxia; Yin, Yanhong; Wang, Zhichao; Shi, Mengjiao; Dong, Hongyu

    2018-01-01

    Onion-derived nitrogen, sulfur self-doped nanoporous carbon spheres (NSC) as efficient metal-free electrocatalyst were synthesized via a facile hydrothermal and subsequent pyrolysis process. The typical NSC with a high BET specific surface area of 1558 m2 g-1, contains 6.23 at.% N and 0.36 at.% S, and possesses high concentration of pyridinic and graphitic nitrogen species. Experimentally, the best performance was the NSC-A2 which showed excellent catalytic activity to oxygen reduction reaction via a 4 electron mechanism with an onset potential of 0.88 V (vs. RHE), and a superior stability comparable to commercial Pt/C catalyst. The high electrocatalytic activity is attributed to not only the synergistic effect of N and S dual doping in carbon and the sufficient active sites, but also its high BET specific surface area and suitable microporous structure. The results demonstrate that it is a simple and scalable approach for preparing efficient and low-cost carbon-based electrocatalysts for oxygen reduction reaction.

  4. IL-12 Influence mTOR to Modulate CD8+ T Cells Differentiation through T-bet and Eomesodermin in Response to Invasive Pulmonary Aspergillosis.

    PubMed

    Wang, Hao; Li, Jingdong; Han, Qiyang; Yang, Fei; Xiao, Yu; Xiao, Meng; Xu, Yingchun; Su, Longxiang; Cui, Na; Liu, Dawei

    2017-01-01

    Objective: To investigate whether mTOR signaling pathway regulate the proliferation and differentiation of CD8 + T cells by transcription factors T-bet and Eomes, and explore the role of IL-12 in this biological procedure. Methods: Aspergillus fumigatus spore suspension nasal inhalation was used to establish the invasive pulmonary aspergillosis (IPA) mouse model. After inoculation, rapamycin (2mg/kg) each day or IL-12 (5ug/kg) every other day was given for 7 days. The blood samples were obtained before the mice sacrificed and lung specimens were taken. Pathological sections were stained with hematoxylin and eosin (HE). The number of CD8 + effective memory T cells (Tem) and the expression of IFN-γ, mTOR, ribosomal protein S6 kinase (S6K), T-bet and EOMES were measured by flow cytometry. The levels of IL-6, IL-10 and Galactomannan (GM) were determined by ELISA. Results: After IL-12 treatment, the number of CD8 + Tem and the expression of IFN-γ increased significantly; while quite the opposite results were observed when the mTOR pathway was blocked by rapamycin. The expression of mTOR and S6K as well as the level of IFN-γ of the IL-12 treatment group were significantly higher than those in IPA and IPA + rapamycin groups. In addition, IL-12 promoted increasing T-bet and down regulating Eomes to make the Tem transformation. The final immune effector was high level of inflammatory cytokines (IL-6) and low level of anti-inflammatory factors (IL-10) and this strengthened immune response to the Aspergillus infection. Conclusions: The biological effects of Tem could significantly affect IPA infection host immune regulation, which depended on the activation of mTOR signaling pathway by IL-12.

  5. Metal-organic framework materials with ultrahigh surface areas

    DOEpatents

    Farha, Omar K.; Hupp, Joseph T.; Wilmer, Christopher E.; Eryazici, Ibrahim; Snurr, Randall Q.; Gomez-Gualdron, Diego A.; Borah, Bhaskarjyoti

    2015-12-22

    A metal organic framework (MOF) material including a Brunauer-Emmett-Teller (BET) surface area greater than 7,010 m.sup.2/g. Also a metal organic framework (MOF) material including hexa-carboxylated linkers including alkyne bond. Also a metal organic framework (MOF) material including three types of cuboctahedron cages fused to provide continuous channels. Also a method of making a metal organic framework (MOF) material including saponifying hexaester precursors having alkyne bonds to form a plurality of hexa-carboxylated linkers including alkyne bonds and performing a solvothermal reaction with the plurality of hexa-carboxylated linkers and one or more metal containing compounds to form the MOF material.

  6. Spectroscopic study on variations in illite surface properties after acid-base titration.

    PubMed

    Liu, Wen-xin; Coveney, R M; Tang, Hong-xiao

    2003-07-01

    FT-IR, Raman microscopy, XRD, 29Si and 27Al MAS NMR, were used to investigate changes in surface properties of a natural illite sample after acid-base potentiometric titration. The characteristic XRD lines indicated the presence of surface Al-Si complexes, preferable to Al(OH)3 precipitates. In the microscopic Raman spectra, the vibration peaks of Si-O and Al-O bonds diminished as a result of treatment with acid, then increased after hydroxide back titration. The varied ratio of signal intensity between (IV)Al and (VI)Al species in 27Al MAS NMR spectra, together with the stable BET surface area after acidimetric titration, suggested that edge faces and basal planes in the layer structure of illite participated in dissolution of structural components. The combined spectroscopic evidence demonstrated that the reactions between illite surfaces and acid-leaching silicic acid and aluminum ions should be considered in the model description of surface acid-base properties of the aqueous illite.

  7. The illusion of specific capture: surface and solution studies of suboptimal oligonucleotide hybridization

    PubMed Central

    2013-01-01

    Background Hybridization based assays and capture systems depend on the specificity of hybridization between a probe and its intended target. A common guideline in the construction of DNA microarrays, for instance, is that avoiding complementary stretches of more than 15 nucleic acids in a 50 or 60-mer probe will eliminate sequence specific cross-hybridization reactions. Here we present a study of the behavior of partially matched oligonucleotide pairs with complementary stretches starting well below this threshold complementarity length – in silico, in solution, and at the microarray surface. The modeled behavior of pairs of oligonucleotide probes and their targets suggests that even a complementary stretch of sequence 12 nt in length would give rise to specific cross-hybridization. We designed a set of binding partners to a 50-mer oligonucleotide containing complementary stretches from 6 nt to 21 nt in length. Results Solution melting experiments demonstrate that stable partial duplexes can form when only 12 bp of complementary sequence are present; surface hybridization experiments confirm that a signal close in magnitude to full-strength signal can be obtained from hybridization of a 12 bp duplex within a 50mer oligonucleotide. Conclusions Microarray and other molecular capture strategies that rely on a 15 nt lower complementarity bound for eliminating specific cross-hybridization may not be sufficiently conservative. PMID:23445545

  8. Mode Specific Electronic Friction in Dissociative Chemisorption on Metal Surfaces: H2 on Ag(111)

    NASA Astrophysics Data System (ADS)

    Maurer, Reinhard J.; Jiang, Bin; Guo, Hua; Tully, John C.

    2017-06-01

    Electronic friction and the ensuing nonadiabatic energy loss play an important role in chemical reaction dynamics at metal surfaces. Using molecular dynamics with electronic friction evaluated on the fly from density functional theory, we find strong mode dependence and a dominance of nonadiabatic energy loss along the bond stretch coordinate for scattering and dissociative chemisorption of H2 on the Ag(111) surface. Exemplary trajectories with varying initial conditions indicate that this mode specificity translates into modulated energy loss during a dissociative chemisorption event. Despite minor nonadiabatic energy loss of about 5%, the directionality of friction forces induces dynamical steering that affects individual reaction outcomes, specifically for low-incidence energies and vibrationally excited molecules. Mode-specific friction induces enhanced loss of rovibrational rather than translational energy and will be most visible in its effect on final energy distributions in molecular scattering experiments.

  9. Surface characteristics and activities of plate-type Raney nickel catalyst

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yoshino, Tomio; Abe, Tuneyo; Abe, Satoshi

    Analytic and morphological studies using SEM, EPMA, and XPS were made on plate-type Raney nickel catalyst with varying contents of aluminum. The surface characteristics and hydrogenation and adsorption behavior of Raney nickel catalysts are discussed. Although the amount of residual aluminum in the catalyst (mainly Al{sub 2}O{sub 3n}H{sub 2}O) remains almost constant on its outermost surface, regardless of the leaching time, it decreases in the interior phases up to a depth of 600 {angstrom} with leaching times over 9 min. The activities of catalysts with average content of aluminum relative to nickel, i.e., 11.6 and 6.8% wt%, in their surfacemore » layers (ca. 0.4 {mu}m thick) were 2.7 and 2.1 mmol/h BET m{sup 2} for the hydrogenation rates of allyl alcohol and 3.6 {times} 10{sup {minus}3} and 2.4 {times} 10{sup {minus}3} mmol/, BET m{sup 2} for the adsorption amount of I{sup {minus}} ion, respectively. These results suggest that the activities for hydrogenation and adsorption were enhanced when the content of residual aluminum in the catalyst was increased, and that the role of the residual aluminum in catalytic reactions can be classified into two types: to provide an increase in active sites due to formation on interstitial lattice defects, and to make a negligible contribution to the formation of active sites because of deposition of Al{sub 2}O{sub 3n}H{sub 2}O on the Raney nickel catalyst.« less

  10. T cell-specific deletion of the inositol phosphatase SHIP reveals its role in regulating Th1/Th2 and cytotoxic responses

    PubMed Central

    Tarasenko, Tatyana; Kole, Hemanta K.; Chi, Anthony W.; Mentink-Kane, Margaret M.; Wynn, Thomas A.; Bolland, Silvia

    2007-01-01

    The 5′-phosphoinositol phosphatase SHIP negatively regulates signaling pathways triggered by antigen, cytokine and Fc receptors in both lymphocytes and myeloid cells. Mice with germ-line (null) deletion of SHIP develop a myeloproliferative-like syndrome that causes early lethality. Lymphocyte anomalies have been observed in SHIP-null mice, but it is unclear whether they are due to an intrinsic requirement of SHIP in these cells or a consequence of the severe myeloid pathology. To precisely address the function of SHIP in T cells, we have generated mice with T cell-specific deletion of SHIP. In the absence of SHIP, we found no differences in thymic selection or in the activation state and numbers of regulatory T cells in the periphery. In contrast, SHIP-deficient T cells do not skew efficiently to Th2 in vitro. Mice with T cell-specific deletion of SHIP show poor antibody responses on Alum/NP-CGG immunization and diminished Th2 cytokine production when challenged with Schistosoma mansoni eggs. The failure to skew to Th2 responses may be the consequence of increased basal levels of the Th1-associated transcriptional factor T-bet, resulting from enhanced sensitivity to cytokine-mediated T-bet induction. SHIP-deficient CD8+ cells show enhanced cytotoxic responses, consistent with elevated T-bet levels in these cells. Overall our experiments indicate that in T cells SHIP negatively regulates cytokine-mediated activation in a way that allows effective Th2 responses and limits T cell cytotoxicity. PMID:17585010

  11. The two-phase flow IPTT method for measurement of nonwetting-wetting liquid interfacial areas at higher nonwetting saturations in natural porous media

    PubMed Central

    Zhong, Hua; Ouni, Asma El; Lin, Dan; Wang, Bingguo; Brusseau, Mark L

    2017-01-01

    Interfacial areas between nonwetting-wetting (NW-W) liquids in natural porous media were measured using a modified version of the interfacial partitioning tracer test (IPTT) method that employed simultaneous two-phase flow conditions, which allowed measurement at NW saturations higher than trapped residual saturation. Measurements were conducted over a range of saturations for a well-sorted quartz sand under three wetting scenarios of primary drainage (PD), secondary imbibition (SI), and secondary drainage (SD). Limited sets of experiments were also conducted for a model glass-bead medium and for a soil. The measured interfacial areas were compared to interfacial areas measured using the standard IPTT method for liquid-liquid systems, which employs residual NW saturations. In addition, the theoretical maximum interfacial areas estimated from the measured data are compared to specific solid surface areas measured with the N2/BET method and estimated based on geometrical calculations for smooth spheres. Interfacial areas increase linearly with decreasing water saturation over the range of saturations employed. The maximum interfacial areas determined for the glass beads, which have no surface roughness, are 32±4 and 36±5 cm−1 for PD and SI cycles, respectively. The values are similar to the geometric specific solid surface area (31±2 cm−1) and the N2/BET solid surface area (28±2 cm−1). The maximum interfacial areas are 274±38, 235±27, and 581±160 cm−1 for the sand for PD, SI, and SD cycles, respectively, and ~7625 cm−1 for the soil for PD and SI. The maximum interfacial areas for the sand and soil are significantly larger than the estimated smooth-sphere specific solid surface areas (107±8 cm−1 and 152±8 cm−1, respectively), but much smaller than the N2/BET solid surface area (1387±92 cm−1 and 55224 cm−1, respectively). The NW-W interfacial areas measured with the two-phase flow method compare well to values measured using the standard

  12. The study of non-fouling and non-specific cellular binding on functionalized surface for mammalian cell identification and manipulation

    NASA Astrophysics Data System (ADS)

    Zainudin, Nor Syuhada; Hambali, Nor Azura Malini Ahmad; Wahid, Mohamad Halim Abd; Retnasamy, Vithyacharan; Shahimin, Mukhzeer Mohamad

    2017-04-01

    Surface functionalization has emerged as a powerful tool for mapping limitless surface-cell membrane interaction in diverse biomolecular applications. Inhibition of non-specific biomolecular and cellular adhesion to solid surfaces is critical in improving the performance of some biomedical devices, particularly for in vitro bioassays. Some factors have to be paid particular attention in determining the right surface modification which are the types of surface, the methods and chemical solution that being used during the experimentation and also tools for analyzing the results. Improved surface functionalization technologies that provide better non-fouling performance in conjunction with specific attachment chemistries are sought for these applications. Hence, this paper serves as a review for multiple surface treatment methods including PEG grafting, adsorptive chemistries, self-assembled monolayers (SAMs) and plasma treatments.

  13. Differential partition of virulent Aeromonas salmonicida and attenuated derivatives possessing specific cell surface alterations in polymer aqueous-phase systems

    NASA Technical Reports Server (NTRS)

    Van Alstine, J. M.; Trust, T. J.; Brooks, D. E.

    1986-01-01

    Two-polymer aqueous-phase systems in which partitioning of biological matter between the phases occurs according to surface properties such as hydrophobicity, charge, and lipid composition are used to compare the surface properties of strains of the fish pathogen Aeromonas salmonicida. The differential ability of strains to produce a surface protein array crucial to their virulence, the A layer, and to produce smooth lipopolysaccharide is found to be important in the partitioning behavior of Aeromonas salmonicida. The presence of the A layer is shown to decrease the surface hydrophilicity of the pathogen, and to increase specifically its surface affinity for fatty acid esters of polyethylene glycol. The method has application to the analysis of surface properties crucial to bacterial virulence, and to the selection of strains and mutants with specific surface characteristics.

  14. The Non-Specific Binding of Fluorescent-Labeled MiRNAs on Cell Surface by Hydrophobic Interaction.

    PubMed

    Lu, Ting; Lin, Zongwei; Ren, Jianwei; Yao, Peng; Wang, Xiaowei; Wang, Zhe; Zhang, Qunye

    2016-01-01

    MicroRNAs are small noncoding RNAs about 22 nt long that play key roles in almost all biological processes and diseases. The fluorescent labeling and lipofection are two common methods for changing the levels and locating the position of cellular miRNAs. Despite many studies about the mechanism of DNA/RNA lipofection, little is known about the characteristics, mechanisms and specificity of lipofection of fluorescent-labeled miRNAs. Therefore, miRNAs labeled with different fluorescent dyes were transfected into adherent and suspension cells using lipofection reagent. Then, the non-specific binding and its mechanism were investigated by flow cytometer and laser confocal microscopy. The results showed that miRNAs labeled with Cy5 (cyanine fluorescent dye) could firmly bind to the surface of adherent cells (Hela) and suspended cells (K562) even without lipofection reagent. The binding of miRNAs labeled with FAM (carboxyl fluorescein) to K562 cells was obvious, but it was not significant in Hela cells. After lipofectamine reagent was added, most of the fluorescently labeled miRNAs binding to the surface of Hela cells were transfected into intra-cell because of the high transfection efficiency, however, most of them were still binding to the surface of K562 cells. Moreover, the high-salt buffer which could destroy the electrostatic interactions did not affect the above-mentioned non-specific binding, but the organic solvent which could destroy the hydrophobic interactions eliminated it. These results implied that the fluorescent-labeled miRNAs could non-specifically bind to the cell surface by hydrophobic interaction. It would lead to significant errors in the estimation of transfection efficiency only according to the cellular fluorescence intensity. Therefore, other methods to evaluate the transfection efficiency and more appropriate fluorescent dyes should be used according to the cell types for the accuracy of results.

  15. An Improved MUSIC Model for Gibbsite Surfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitchell, Scott C.; Bickmore, Barry R.; Tadanier, Christopher J.

    2004-06-01

    Here we use gibbsite as a model system with which to test a recently published, bond-valence method for predicting intrinsic pKa values for surface functional groups on oxides. At issue is whether the method is adequate when valence parameters for the functional groups are derived from ab initio structure optimization of surfaces terminated by vacuum. If not, ab initio molecular dynamics (AIMD) simulations of solvated surfaces (which are much more computationally expensive) will have to be used. To do this, we had to evaluate extant gibbsite potentiometric titration data that where some estimate of edge and basal surface area wasmore » available. Applying BET and recently developed atomic force microscopy methods, we found that most of these data sets were flawed, in that their surface area estimates were probably wrong. Similarly, there may have been problems with many of the titration procedures. However, one data set was adequate on both counts, and we applied our method of surface pKa int prediction to fitting a MUSIC model to this data with considerable success—several features of the titration data were predicted well. However, the model fit was certainly not perfect, and we experienced some difficulties optimizing highly charged, vacuum-terminated surfaces. Therefore, we conclude that we probably need to do AIMD simulations of solvated surfaces to adequately predict intrinsic pKa values for surface functional groups.« less

  16. Specific heats of lunar surface materials from 90 to 350 degrees Kelvin

    USGS Publications Warehouse

    Robie, R.A.; Hemingway, B.S.; Wilson, W.H.

    1970-01-01

    The specific heats of lunar samples 10057 and 10084 returned by the Apollo 11 mission have been measured between 90 and 350 degrees Kelvin by use of an adiabatic calorimeter. The samples are representative of type A vesicular basalt-like rocks and of finely divided lunar soil. The specific heat of these materials changes smoothly from about 0.06 calorie per gram per degree at 90 degrees Kelvin to about 0.2 calorie per gram per degree at 350 degrees Kelvin. The thermal parameter ??=(k??C)-1/2 for the lunar surface will accordingly vary by a factor of about 2 between lunar noon and midnight.

  17. Astrocytes Specifically Remove Surface-Adsorbed Fibrinogen and Locally Express Chondroitin Sulfate Proteoglycans

    PubMed Central

    Hsiao, Tony W.; Swarup, Vimal P.; Kuberan, Balagurunathan; Tresco, Patrick A.; Hlady, Vladimir

    2013-01-01

    Surface-adsorbed fibrinogen (FBG) was recognized by adhering astrocytes and removed from the substrates in vitro by a two-phase removal process. The cells removed adsorbed FBG from binary proteins surface patterns (FBG + laminin, or FBG + albumin) while leaving the other protein behind. Astrocytes preferentially expressed chondroitin sulfate proteoglycan (CSPG) at the loci of fibrinogen stimuli; however no differences in overall CSPG production as a function of FBG surface coverage were identified. Removal of FBG by astrocytes was also found to be independent of transforming growth factor type β (TGF-β) receptor based signaling as cells maintained CSPG production in the presence of TGF-β receptor kinase inhibitor, SB 431542. The inhibitor decreased CSPG expression, but did not abolicsh it entirely. Because blood contact and subsequent FBG adsorption are unavoidable in neural implantations, the results indicate that implant-adsorbed FBG may contribute to reactive astrogliosis around the implant as astrocytes specifically recognize adsorbed FBG. PMID:23499985

  18. Surface characterization and chemical analysis of bamboo substrates pretreated by alkali hydrogen peroxide.

    PubMed

    Song, Xueping; Jiang, Yan; Rong, Xianjian; Wei, Wei; Wang, Shuangfei; Nie, Shuangxi

    2016-09-01

    The surface characterization and chemical analysis of bamboo substrates by alkali hydrogen peroxide pretreatment (AHPP) were investigated in this study. The results tended to manifest that AHPP prior to enzymatic and chemical treatment was potential for improving accessibility and reactivity of bamboo substrates. The inorganic components, organic solvent extractives and acid-soluble lignin were effectively removed by AHPP. X-ray photoelectron spectroscopy (XPS) analysis indicated that the surface of bamboo chips had less lignin but more carbohydrate after pre-treatment. Fiber surfaces became etched and collapsed, and more pores and debris on the substrate surface were observed with Scanning Electron Microscopy (SEM). Brenauer-Emmett-Teller (BET) results showed that both of pore volume and surface area were increased after AHPP. Although XRD analysis showed that AHPP led to relatively higher crystallinity, pre-extraction could overall enhance the accessibility of enzymes and chemicals into the bamboo structure. Copyright © 2016. Published by Elsevier Ltd.

  19. Laminar shear stress modulates endothelial luminal surface stiffness in a tissue-specific manner.

    PubMed

    Merna, Nick; Wong, Andrew K; Barahona, Victor; Llanos, Pierre; Kunar, Balvir; Palikuqi, Brisa; Ginsberg, Michael; Rafii, Shahin; Rabbany, Sina Y

    2018-04-17

    Endothelial cells form vascular beds in all organs and are exposed to a range of mechanical forces that regulate cellular phenotype. We sought to determine the role of endothelial luminal surface stiffness in tissue-specific mechanotransduction of laminar shear stress in microvascular mouse cells and the role of arachidonic acid in mediating this response. Microvascular mouse endothelial cells were subjected to laminar shear stress at 4 dynes/cm 2 for 12 hours in parallel plate flow chambers that enabled real-time optical microscopy and atomic force microscopy measurements of cell stiffness. Lung endothelial cells aligned parallel to flow, while cardiac endothelial cells did not. This rapid alignment was accompanied by increased cell stiffness. The addition of arachidonic acid to cardiac endothelial cells increased alignment and stiffness in response to shear stress. Inhibition of arachidonic acid in lung endothelial cells and embryonic stem cell-derived endothelial cells prevented cellular alignment and decreased cell stiffness. Our findings suggest that increased endothelial luminal surface stiffness in microvascular cells may facilitate mechanotransduction and alignment in response to laminar shear stress. Furthermore, the arachidonic acid pathway may mediate this tissue-specific process. An improved understanding of this response will aid in the treatment of organ-specific vascular disease. © 2018 John Wiley & Sons Ltd.

  20. Snow specific surface area simulation using the one-layer snow model in the Canadian LAnd Surface Scheme (CLASS)

    NASA Astrophysics Data System (ADS)

    Roy, A.; Royer, A.; Montpetit, B.; Bartlett, P. A.; Langlois, A.

    2012-12-01

    Snow grain size is a key parameter for modeling microwave snow emission properties and the surface energy balance because of its influence on the snow albedo, thermal conductivity and diffusivity. A model of the specific surface area (SSA) of snow was implemented in the one-layer snow model in the Canadian LAnd Surface Scheme (CLASS) version 3.4. This offline multilayer model (CLASS-SSA) simulates the decrease of SSA based on snow age, snow temperature and the temperature gradient under dry snow conditions, whereas it considers the liquid water content for wet snow metamorphism. We compare the model with ground-based measurements from several sites (alpine, Arctic and sub-Arctic) with different types of snow. The model provides simulated SSA in good agreement with measurements with an overall point-to-point comparison RMSE of 8.1 m2 kg-1, and a RMSE of 4.9 m2 kg-1 for the snowpack average SSA. The model, however, is limited under wet conditions due to the single-layer nature of the CLASS model, leading to a single liquid water content value for the whole snowpack. The SSA simulations are of great interest for satellite passive microwave brightness temperature assimilations, snow mass balance retrievals and surface energy balance calculations with associated climate feedbacks.

  1. Flow-induced detachment of red blood cells adhering to surfaces by specific antigen-antibody bonds.

    PubMed

    Xia, Z; Goldsmith, H L; van de Ven, T G

    1994-04-01

    Fixed spherical swollen human red blood cells of blood type B adhering on a glass surface through antigen-antibody bonds to monoclonal mouse antihuman IgM, adsorbed or covalently linked on the surface, were detached by known hydrodynamic forces created in an impinging jet. The dynamic process of detachment of the specifically bound cells was recorded and analyzed. The fraction of adherent cells remaining on the surface decreased with increasing hydrodynamic force. For an IgM coverage of 0.26%, a tangential force on the order of 100 pN was able to detach almost all of the cells from the surface within 20 min. After a given time of exposure to hydrodynamic force, the fraction of adherent cells remaining increased with time, reflecting an increase in adhesion strength. The characteristic time for effective aging was approximately 4 h. Results from experiments in which the adsorbed antibody molecules were immobilized through covalent coupling and from evanescent wave light scattering of adherent cells, imply that deformation of red cells at the contact area was the principal cause for aging, rather than local clustering of the antibody through surface diffusion. Experiments with latex beads specifically bound to red blood cells suggest that, instead of breaking the antigen-antibody bonds, antigen molecules were extracted from the cell membrane during detachment.

  2. Preparation and surface characterization of activated carbons from Euphorbia rigida by chemical activation with ZnCl2, K2CO3, NaOH and H3PO4

    NASA Astrophysics Data System (ADS)

    Kılıç, Murat; Apaydın-Varol, Esin; Pütün, Ayşe Eren

    2012-11-01

    Preparation of activated carbons from Euphorbia rigida by chemical activation with different impregnation agents and ratios was studied. ZnCl2, K2CO3, NaOH and H3PO4 were used as chemical activation agents and four impregnation ratios (25-50-75-100%) by mass were applied on biomass. Activation is applied to impregnated biomass samples at 700 °C under sweeping gas in a fixed bed reactor. For determination of chemical and physical properties of the obtained activated carbons; elemental analysis was applied to determine the elemental composition (C, H, N, O) and FT-IR spectra was used to analyze the functional groups. BET equation was used to calculate the surface areas of activated carbons. For understanding the changes in the surface structure, activated carbons were conducted to Scanning Electron Microscopy (SEM). Maximum BET surface area (2613 m2/g) was reached with 75% K2CO3 impregnated biomass sample. Experimental results showed that impregnation types and ratios have a significant effect on the pore structure of activated carbon and E. rigida seems to be an alternative precursor for commercial activated carbon production.

  3. Face specificity and the role of metal adatoms in molecular reorientation at surfaces

    NASA Astrophysics Data System (ADS)

    Perry, C. C.; Haq, S.; Frederick, B. G.; Richardson, N. V.

    1998-07-01

    Using reflection absorption infrared spectroscopy (RAIRS), the coverage-dependent reorientation of the benzoate species on the (110) and (111) faces of copper is compared and contrasted. Whereas on Cu(110) benzoate reorients from a flat-lying to an upright orientation with increasing coverage, on Cu(111), at all coverages, benzoate is aligned normal to the surface. The formation of periodic, flat-lying copper-benzoate structures has been attributed to the availability of metal adatoms, which differs dramatically between the (111) and (110) faces. We discuss the face specificity of molecular orientation by comparing calculated formation energies of adatom vacancies from ledges and kink sites on (100), (110) and (111) faces. Further support for this model is given by the evaporation of sodium, either by pre- or post-dosing, onto low-coverage benzoate/Cu(111), which induces benzoate to convert from a perpendicular to a parallel orientation. Likewise, coevaporation of Cu while dosing benzoic acid onto the Cu(111) surface also results in a majority of flat-lying benzoate species. Finally, for adsorption on the p(2×1)O/Cu(110) reconstruction, benzoate occurs only as the upright species, which is consistent with reducing the copper mobility and availability on the (110) face. We therefore suggest the possible role of metal adatoms as a new mechanism in controlling adsorbate orientation and therefore face specificity in surface reactions.

  4. Influences of internal resistance and specific surface area of electrode materials on characteristics of electric double layer capacitors

    NASA Astrophysics Data System (ADS)

    Suda, Yoshiyuki; Mizutani, Akitaka; Harigai, Toru; Takikawa, Hirofumi; Ue, Hitoshi; Umeda, Yoshito

    2017-01-01

    We fabricated electric double layer capacitors (EDLCs) using particulate and fibrous types of carbon nanomaterials with a wide range of specific surface areas and resistivity as an active material. The carbon nanomaterials used in this study are carbon nanoballoons (CNBs), onion-like carbon (OLC), and carbon nanocoils (CNCs). A commercially used activated carbon (AC) combined with a conductive agent was used as a comparison. We compared the EDLC performance using cyclic voltammetry (CV), galvanostatic charge/discharge testing, and electrochemical impedance spectroscopy (EIS). OLC showed a poor EDLC performance, although it has the lowest resistivity among the carbon nanomaterials. CNB, which has a 1/16 lower specific surface area than AC but higher specific surface area than CNC and OLC, had a higher specific capacitance than CNC and OLC. Moreover, at current densities of 1.5 Ag-1 and larger, the specific capacitance of the EDLC using CNB was almost the same as that using AC. Electrochemical impedance spectroscopy of the EDLCs revealed that the CNB and CNC electrodes had a much lower internal resistance than the AC electrode, which correlated with a low capacitance maintenance factor as the current density increased.

  5. Fabrication and characterization of akaganeite/graphene oxide nanocomposite for arsenic removal from water

    NASA Astrophysics Data System (ADS)

    Trang, Nguyen Thi Thuy; Thy, Lu Thi Mong; Cuong, Pham Mai; Tu, Tran Hoang; Hieu, Nguyen Huu

    2018-04-01

    In this study, akageneite/graphene oxide (β-FeOOH/GO) nanocomposite was fabricated by in situ forced hydrolysis of iron (III) chloride. The structure and morphology of β-FeOOH/GO were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer-Emmett- Teller (BET) specific surface area. XRD, FTIR, and TEM results indicated that β-FeOOH nanoparticles were successfully decorated on the surface of GO nanosheets. The BET specific surface area of β-FeOOH/GO was observed of 97.94 m2/g. The nanocomposite was used as an adsorbent for removal of arsenic (As5+) from water. Adsorption experiments were carried out to investigate contact time, pH values, and As5+ initial concentrations. The adsorption equilibrium time was reached within 180 minutes. The adsorption was well-fitted by a pseudo-second-order kinetic and Langmuir isotherm model. The maximum adsorption capacity of β-FeOOH/GO for As5+ ions of 94.34 mg/g that was calculated from the Langmuir model at pH 3. Accordingly, the nanocomposite β-FeOOH/GO could be considered as a highly efficient adsorbent for removing arsenic from water.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Hongfen, E-mail: wanghongfen11@163.com; Wang, Zhiqi; Chen, Shougang

    Molybdenum carbides with surfactants as carbon sources were prepared using the carbothermal reduction of the appropriate precursors (molybdenum oxides deposited on surfactant micelles) at 1023 K under hydrogen gas. The carburized products were characterized using scanning electron microscopy (SEM), X-ray diffraction and BET surface area measurements. From the SEM images, hollow microspherical and rod-like molybdenum carbides were observed. X-ray diffraction patterns showed that the annealing time of carburization had a large effect on the conversion of molybdenum oxides to molybdenum carbides. And BET surface area measurements indicated that the difference of carbon sources brought a big difference in specific surfacemore » areas of molybdenum carbides. - Graphical abstract: Molybdenum carbides having hollow microspherical and hollow rod-like morphologies that are different from the conventional monodipersed platelet-like morphologies. Highlights: Black-Right-Pointing-Pointer Molybdenum carbides were prepared using surfactants as carbon sources. Black-Right-Pointing-Pointer The kinds of surfactants affected the morphologies of molybdenum carbides. Black-Right-Pointing-Pointer The time of heat preservation at 1023 K affected the carburization process. Black-Right-Pointing-Pointer Molybdenum carbides with hollow structures had larger specific surface areas.« less

  7. Mode-specific vibrational excitation and energy redistribution after ultrafast intramolecular electron transfer

    NASA Astrophysics Data System (ADS)

    Hogiu, S.; Werncke, W.; Pfeiffer, M.; Dreyer, J.; Elsaesser, T.

    2000-07-01

    Vibrational relaxation in the electronic ground state initiated by intramolecular back-electron transfer (b-ET) of betaine-30 (B-30) is studied by picosecond time-resolved anti-Stokes Raman spectroscopy. Measurements were carried out with B-30 dissolved in slowly as well as in rapidly relaxing solvents. We observed a risetime of the Raman band with the highest frequency near 1600 cm-1 which is close to the b-ET time τb-ET of B-30. For B-30 dissolved in propylene carbonate (τb-ET˜1 ps), the population of this mode exhibits a rise time of 1 ps whereas vibrational populations between 400 and 1400 cm-1 increase substantially slower. In contrast, in glycerol triacetin (τb-ET˜3.5 ps) and in ethanol (τb-ET˜6 ps) rise times of all modes are close to the respective b-ET times. Within the first few picoseconds, direct vibrational excitation through b-ET is favored for modes with the highest frequencies and high Franck-Condon factors. Later on, indirect channels of population due to vibrational energy redistribution (IVR) become effective. Thermal equilibrium populations of the Raman active modes are established within 10 to 15 ps after optical excitation.

  8. Surface charge-specific interactions between polymer nanoparticles and ABC transporters in Caco-2 cells

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, Sourav; van Opstal, Edward J.; Alink, Gerrit M.; Marcelis, Antonius T. M.; Zuilhof, Han; Rietjens, Ivonne M. C. M.

    2013-06-01

    The surface charge-dependent transport of polymeric nanoparticles (PNPs) across Caco-2 monolayers grown on transwell culture systems as an in vitro model for intestinal transport was tested. The transport of well-characterized, monodisperse, and fluorescent tri-block copolymer nanoparticles (TCNPs/size 45 nm) and polystyrene nanoparticles (PSNPs/size 50 nm), with different surface charges (positive and negative), was quantified. The positive PNPs showed a higher intracellular uptake and flux across the Caco-2 monolayers than the negative PNPs. Multidrug resistance/P-glycoprotein (MDR1/P-gp), a specific ATP-binding cassette (ABC) transporter, was found to play a major role in the cellular efflux of positive PNPs, whereas the multidrug resistance protein 1 took part in the efflux of negative PNPs from Caco-2 cells. The positive PNPs also caused an increased cellular uptake and apical to basolateral transport of the carcinogen PhIP across the Caco-2 monolayer. The flavonoid quercetin, which is known to interact with ABC transporters, promoted the intracellular uptake of different PNPs and interfered with the normal distribution patterns of PNPs in the transwell system. These results indicate that PNPs display surface charge-specific interactions with ABC transporters and can even affect the bioavailability of toxic food-borne compounds (like pro-carcinogens).

  9. A facile hydrothermal approach to synthesize rGO/BiVO4 photocatalysts for visible light induced degradation of RhB dye

    NASA Astrophysics Data System (ADS)

    Pal, Shreyasi; Dutta, Shibsankar; De, Sukanta

    2018-05-01

    RGO/BiVO4 composites were synthesized by a simple hydrothermal method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM) and surface analysis (BET). The photocatalytic activity of the as-prepared samples was evaluated by studying the degradation of model dyes rhodamine B (RhB) under visible light. The prepared rGO/BiVO4 composites exhibited higher photocatalytic activity for the degradation of RhB with a maximum removal rate of 86% under visible light irradiation under visible-light irradiation than pure BiVO4 nanoparticles (63%). This behavior could be associated to their higher specific surface area (BET), increased light absorption intensity and the degradation of electron-hole pair recombination in BiVO4 with the introduction of the rGO.

  10. Precise orbit determination of BeiDou constellation based on BETS and MGEX network

    PubMed Central

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-01-01

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved. PMID:24733025

  11. Precise orbit determination of BeiDou constellation based on BETS and MGEX network.

    PubMed

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-04-15

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved.

  12. Surface engineered magnetic nanoparticles for specific immunotargeting of cadherin expressing cells

    NASA Astrophysics Data System (ADS)

    Moros, Maria; Delhaes, Flavien; Puertas, Sara; Saez, Berta; de la Fuente, Jesús M.; Grazú, Valeria; Feracci, Helene

    2016-02-01

    In spite of historic advances in cancer biology and recent development of sophisticated chemotherapeutics, the outlook for patients with advanced cancer is still grim. In this sense nanoparticles (NPs), through their unique physical properties, enable the development of new approaches for cancer diagnosis and treatment. Thus far the most used active targeting scheme involves NPs functionalization with antibodies specific to molecules overexpressed on cancer cell’s surface. Therefore, such active targeting relies on differences in NPs uptake kinetics rates between tumor and healthy cells. Many cancers of epithelial origin are associated with the inappropriate expression of non-epithelial cadherins (e.g. N-, P-, -11) with concomitant loss of E-cadherin. Such phenomenon named cadherin switching favors tumor development and metastasis via interactions of tumor cells with stromal components. That is why we optimized the oriented functionalization of fluorescently labelled magnetic NPs with a novel antibody specific for the extracellular domain of cadherin-11. The obtained Ab-NPs exhibited high specificity when incubated with two cell lines used as models of tumor and healthy cells. Thus, cadherin switching offers a great opportunity for the development of active targeting strategies aimed to improve the early detection and treatment of cancer.

  13. Utilization of specific and non-specific peptide interactions with inorganic nanomaterials on the surface of bacteriophage M13: Methodologies towards phage supported bi-functional materials

    NASA Astrophysics Data System (ADS)

    Avery, Kendra Nicole

    Many types of organisms create a variety of nano and micro scale materials from precursors available in their surrounding environments by a process called biomineralization. As scientists begin to understand how these organisms utilize specific and non-specific interactions with a variety of biopolymers such as chitin, peptides, proteins and nucleic acids with these precursors to create inorganic/organic composite materials, they have begun to wonder about the synthesis of other types of non-biologically templated synthetic techniques that might be possible. Bioengineered organisms and biopolymers have begun to be used for these types of studies. A variety of selection techniques exist for discovering biopolymers with an affinity for a target material, however, one of the most notable is a technique called peptide phage display. This is a technique that utilizes a commercially available randomized peptide library attached at the tip of the filamentous bacteriophage M13. In this dissertation capabilities of bacteriophage M13 are explored in regard to the creation of bi-functional nano materials by exploiting both specific peptide interactions as well as non-specific peptide interactions on the surface of the organism. Chapter 2 focuses on utilizing the specific peptide interactions of the randomized library at pIII in order to discover peptides with high binding affinity for a variety of nanomaterials. Selection studies called biopanning are performed on a variety of nanomaterials such as CaMoO4, allotropes of Ni, Fe2O3 and Fe3O4, and Rh and Pt with the fcc type crystal structure. Similarities and differences between peptides discovered for these materials are discussed. Chapter 3 focuses on utilizing the non-specific peptide interactions on the long axis of M13 called pVIII. The pVIII region consists of 2700 copies of the same 50 amino acid protein which as a negatively charged domain which is exposed to solution. The pVIII region therefore provides the surface of

  14. Kinetics and thermodynamics studies on the BMP-2 adsorption onto hydroxyapatite surface with different multi-morphological features.

    PubMed

    Lu, Zhiwei; Huangfu, Changxin; Wang, Yanying; Ge, Hongwei; Yao, Yao; Zou, Ping; Wang, Guangtu; He, Hua; Rao, Hanbing

    2015-01-01

    The effect of the surface topography on protein adsorption process is of great significance for designing hydroxyapatite (HA) ceramic material surfaces. In this work, three different topographies of HA materials HA-sheet, HA-rod, and HA-whisker were synthesized and testified by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer-Emmett-Teller (BET) and a field emission scanning electron microscopy (FE-SEM). We have systematically investigated the adsorption kinetics and thermodynamics of bone morphogenetic proteins (BMP-2) on the three different topography surfaces of HA, respectively. The results showed that the maximum adsorption capacities of HA-sheet, HA-rod and HA-whisker were (219.96 ± 10.18), (247.13 ± 12.35), and (354.67 ± 17.73) μg · g(-1), respectively. Kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated as well as discussed. It demonstrated that the adsorption of BMP-2 onto HA could be described by the pseudo second-order equation. Adsorption of BMP-2 onto HA followed the Langmuir isotherm. It confirmed that compared with other samples HA-whisker had more adsorption sites for its high specific surface area which could provide more opportunities for protein molecules. The adsorption processes were endothermic (ΔH > 0), spontaneous (ΔG < 0) and entropy increasing (ΔS > 0). A possible adsorption mechanism has been proposed. In addition, the BMP-2 could be adsorbed to the surface which existed slight conformational changes by FT-IR. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Porous properties of activated carbons from waste newspaper prepared by chemical and physical activation.

    PubMed

    Okada, Kiyoshi; Yamamoto, Nobuo; Kameshima, Yoshikazu; Yasumori, Atsuo

    2003-06-01

    Activated carbons were prepared from old newspaper and paper prepared from simulated paper sludge by chemical activation using various alkali carbonates and hydroxides as activating reagents and also by physical activation using steam. In the chemical activation, the influence of oxidation, carbonization, and activation on the porous properties of the resulting activated carbons was investigated. The specific surface areas (S(BET)) of the activated carbons prepared by single-step activation (direct activation without oxidation and carbonization) were higher than those resulting from two-step activation (oxidation-activation and carbonization-activation) and three-step activation (oxidation-carbonization-activation) methods. The S(BET) values were strongly dependent on the activating reagents and the activating conditions, being >1000 m(2)/g using K(2)CO(3), Rb(2)CO(3), Cs(2)CO(3), and KOH as activating reagents but <1000 m(2)/g using Li(2)CO(3), Na(2)CO(3), and NaOH. These differences in S(BET) values are suggested to be related to the ionic radii of the alkalis used as activating reagents. The microstructures of the higher S(BET) samples show a complete loss of fiber shape but those of the lower S(BET) samples maintain the shape. In the physical activation, the porous properties of the activated carbons prepared by the single-step method were examined as a function of the production conditions such as activation temperature, activation time, steam concentration, and flow rate of the carrier gas. The maximum S(BET) and total pore volume (V(P)) were 1086 m(2)/g and 1.01 ml/g, obtained by activation at 850 degrees C for 2 h, flowing 20 mol% of steam in nitrogen gas at 0.5 l/min. A correlation was found between S(BET) and the yield of the product, the maximum S(BET) value corresponding to a product yield of about 10%. This result is suggested to result from competition between pore formation and surface erosion. Compared with chemically activated carbons using K(2)CO

  16. Surface restructuring of red mud to produce FeO x (OH) y sites and mesopores for the efficient complexation/adsorption of β-lactam antibiotics.

    PubMed

    Pinto, Paula S; Lanza, Giovani D; Souza, Mayra N; Ardisson, José D; Lago, Rochel M

    2018-03-01

    In this work, iron oxide in the red mud (RM) waste was restructured to produce mesopores with surface [FeO x (OH) y ] sites for the efficient complexation/adsorption of β-lactam antibiotics. Red mud composed mainly by hematite was restructured by an acid/base process followed by a thermal treatment at 150-450 °C (MRM150, MRM200, MRM300, and MRM450) and fully characterized by Mössbauer, XRD, FTIR, BET, SEM, CHN, and thermogravimetric analyses. The characterization data showed a highly dispersed Fe 3+ oxyhydroxy phase, which was thermally dehydrated to a mesoporous α-Fe 2 O 3 with surface areas in the range of 141-206 m 2  g -1 . These materials showed high efficiencies (21-29 mg g -1 ) for the adsorption of β-lactam antibiotics, amoxicillin, cephalexin, and ceftriaxone, and the data was better fitted by the Langmuir model isotherm (R 2  = 0.9993) with monolayer adsorption capacity of ca. 39 mg g -1 for amoxicillin. Experiments such as competitive adsorption in the presence of phosphate and H 2 O 2 decomposition suggested that the β-lactamic antibiotics might be interacting with surface [FeO x (OH) y ] species by a complexation process. Moreover, the OH/Fe ratio, BET surface area and porosity indicated that this complexation is occurring especially on [FeO x (OH) y ] surf sites contained in the mesopore space.

  17. Specific surface area effect on adsorption of chlorpyrifos and TCP by soils and modeling

    USDA-ARS?s Scientific Manuscript database

    The adsorption of chlorpyrifos and TCP (3,5,6, trichloro-2-pyridinol) was determined in four soils (Mollisol, Inceptisol, Entisol, Alfisol) having different specific surface areas (19–84 m2/g) but rather similar organic matter content (2.4–3.5%). Adsorption isotherms were derived from batch equilibr...

  18. A monoclonal antibody recognizes undifferentiation-specific carbohydrate moieties expressed on cell surface of the human dental pulp cells.

    PubMed

    Kang, Kyung-Jung; Ko, Seon-Yle; Ryu, Chun-Jeih; Jang, Young-Joo

    2017-05-01

    Human dental pulp cells are obtained from dental pulp tissue, and have the ability to form dentin and a pulp-like complex. Although adult stem cells have been identified from the primary culture by using specific cell surface markers, the identity of surface markers for the purification of stem cells within the dental pulp population are still unclear. Previously, we had constructed monoclonal antibodies against the undifferentiated cell-specific surface markers of human dental pulp cells (hDPCs) by performing decoy immunization. Among them, a monoclonal antibody against the cell surface antigen of the undifferentiated hDPCs (named UPSA-1) was purified and its heavy and light chain consensus regions were analyzed. The cell surface binding affinity of UPSA-1 mAb on the undifferentiated hDPCs was stronger than that on the differentiated cells. When tunicamycin was applied to hDPSCs during culture, the cell surface binding affinity of the antibody was dramatically decreased, and dentinogenic differentiation was reduced. The purified UPSA-1 antigen band resulting from immunoprecipitation disappeared or shifted down on the SDS-PAGE by deglycosylation. These data suggested that glycosylation on the cell surface might be a marker of an undifferentiated state, and that UPSA-1 mAb might be useful for identifying the carbohydrate moiety on the cell surface of undifferentiated pulp cells. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  19. A key parameter on the adsorption of diluted aniline solutions with activated carbons: The surface oxygen content.

    PubMed

    Pardo, Beatrice; Ferrer, Nabí; Sempere, Julià; Gonzalez-Olmos, Rafael

    2016-11-01

    A total of 11 different commercial activated carbons (AC) with well characterized textural properties and oxygen surface content were tested as adsorbents for the removal of aniline as a target water pollutant. The maximum adsorption capacity of aniline for the studied AC was from 138.9 to 257.9 mg g(-1) at 296.15 K and it was observed to be strongly related to the textural properties of the AC, mainly with the BET surface area and the micropore volume. It was not observed any influence of the oxygen surface content of the AC on the maximum adsorption capacity. However, it was found that at low aniline aqueous concentration, the presence of oxygen surface groups plays a dominant role during the adsorption. A high concentration of oxygen surface groups, mainly carboxylic and phenolic groups, decreases the aniline adsorption regardless of the surface area of the AC. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. The preparation, surface structure, zeta potential, surface charge density and photocatalytic activity of TiO2 nanostructures of different shapes

    NASA Astrophysics Data System (ADS)

    Grover, Inderpreet Singh; Singh, Satnam; Pal, Bonamali

    2013-09-01

    Titania based nanocatalysts such as sodium titanates of different morphology having superior surface properties are getting wide importance in photocatalysis research. Despite having sodium (Na) contents and its high temperature synthesis (that generally deteriorate the photoreactivity), these Na-titanates often exhibit better photoactivity than P25-TiO2 catalyst. Hence, this work demonstrated the influence of crystal structure, BET surface area, surface charge, zeta potential (ζ) and metal loading on the photocatalytic activity of as-prepared sodium titanate nanotube (TNT) and titania nanorod (TNR). Straw like hollow orthorhombic-TNT (Na2Ti2O5·H2O) particles (W = 9-12 nm and L = 82-115 nm) and rice like pure anatase-TNR particles (W = 8-13 nm and L = 81-134 nm) are obtained by the hydrothermal treatment of P25-TiO2 with NaOH, which in fact, altered the net surface charge of TNT and TNR particles. The observed ζ = -2.82 (P25-TiO2), -13.5 (TNT) and -22.5 mV (TNR) are significantly altered by the Ag and Cu deposition. It has been found here that TNT displayed best photocatalytic activity for the imidacloprid insecticide (C9H10ClN5O2) degradation to CO2 formation under UV irradiation because of its largest surface area 176 m2 g-1 among the catalysts studied.

  1. Rangeland Brush Estimation Toolbox (RaBET): An Approach for Evaluating Brush Management Conservation Efforts in Western Grazing Lands

    NASA Astrophysics Data System (ADS)

    Holifield Collins, C.; Kautz, M. A.; Skirvin, S. M.; Metz, L. J.

    2016-12-01

    There are over 180 million hectares of rangelands and grazed forests in the central and western United States. Due to the loss of perennial grasses and subsequent increased runoff and erosion that can degrade the system, woody cover species cannot be allowed to proliferate unchecked. The USDA-Natural Resources Conservation Service (NRCS) has allocated extensive resources to employ brush management (removal) as a conservation practice to control woody species encroachment. The Rangeland-Conservation Effects Assessment Project (CEAP) has been tasked with determining how effective the practice has been, however their land managers lack a cost-effective means to conduct these assessments at the necessary scale. An ArcGIS toolbox for generating large-scale, Landsat-based, spatial maps of woody cover on grazing lands in the western United States was developed through a collaboration with NRCS Rangeland-CEAP. The toolbox contains two main components of operation, image generation and temporal analysis, and utilizes simple interfaces requiring minimum user inputs. The image generation tool utilizes geographically specific algorithms developed from combining moderate-resolution (30-m) Landsat imagery and high-resolution (1-m) National Agricultural Imagery Program (NAIP) aerial photography to produce the woody cover scenes at the Major Land Resource (MLRA) scale. The temporal analysis tool can be used on these scenes to assess treatment effectiveness and monitor woody cover reemergence. RaBET provides rangeland managers an operational, inexpensive decision support tool to aid in the application of brush removal treatments and assessing their effectiveness.

  2. Topography of the casein micelle surface by surface plasmon resonance (SPR) using a selection of specific monoclonal antibodies.

    PubMed

    Dupont, Didier; Johansson, Annette; Marchin, Stephane; Rolet-Repecaud, Odile; Marchesseau, Sylvie; Leonil, Joelle

    2011-08-10

    Several theoretical models of the casein micelle structure have been proposed in the past, but the exact organization of the four individual caseins (α(s1), α(s2), β, and κ) within this supramolecular structure remains unknown. The present study aims at determining the topography of the casein micelle surface by following the interaction between 44 monoclonal antibodies specific for different epitopes of α(s1)-, α(s2)-, β-, and κ-casein and the casein micelle in real time and no labeling using a surface plasmon resonance (SPR)-based biosensor. Although the four individual caseins were found to be accessible for antibody binding, data confirmed that the C-terminal extremity of κ-casein was highly accessible and located at the periphery of the structure. When casein micelles were submitted to proteolysis, the C-terminal extremity of κ-casein was rapidly hydrolyzed. Disintegration of the micellar structure resulted in an increased access for antibodies to hydrophobic areas of α(s1)- and α(s2)-casein.

  3. Fabrication of polyamide thin-film nanocomposite membranes with enhanced surface charge for nitrate ion removal from water resources.

    PubMed

    Ghaee, A; Zerafat, M M; Askari, P; Sabbaghi, S; Sadatnia, B

    2017-03-01

    Exclusion due to membrane surface charge is considered as one of the main separation mechanisms occurring in charged membranes, which can be varied through various approaches to affect membrane rejection performance. In this study, thin-film composite (TFC) polyamide (PA) membranes were fabricated via interfacial polymerization of m-phenylenediamine (m-PDA) and 2,4-diaminobenzene sulfonic acid with trimesoyl chloride (TMC) on a polysulfone sub-layer. The ability of the prepared membrane to remove nitrate ions from water resources has been investigated. In order to improve membrane permeability, zeolite-PA thin film nanocomposite (TFN) membranes were fabricated by incorporating natural zeolite nanoparticles obtained through ball milling of an Iranian natural zeolite powder in the interfacial polymerization process. The size, morphology and specific surface area of the as-obtained nanozeolite were characterized using particle size analysis, FE-SEM and BET. The functional groups, morphology and surface charge of the membrane were characterized using ATR-FTIR, SEM and zeta potential analyses. Also, field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) were used to determine the distribution of nanozeolite in TFN membranes. The influence of zeolite addition to surface roughness was accessed by atomic force microscopy. The performance of TFC and TFN membranes was evaluated in terms of pure water flux and nitrate rejection. The results showed that in case of sulfonated diamine, nitrate ions rejection was enhanced from 63% to 85% which could be attributed to surface charge enhancement. TFN permeability was almost doubled by the addition of nanozeolite.

  4. Surface mesh to voxel data registration for patient-specific anatomical modeling

    NASA Astrophysics Data System (ADS)

    de Oliveira, Júlia E. E.; Giessler, Paul; Keszei, András.; Herrler, Andreas; Deserno, Thomas M.

    2016-03-01

    Virtual Physiological Human (VPH) models are frequently used for training, planning, and performing medical procedures. The Regional Anaesthesia Simulator and Assistant (RASimAs) project has the goal of increasing the application and effectiveness of regional anesthesia (RA) by combining a simulator of ultrasound-guided and electrical nerve-stimulated RA procedures and a subject-specific assistance system through an integration of image processing, physiological models, subject-specific data, and virtual reality. Individualized models enrich the virtual training tools for learning and improving regional anaesthesia (RA) skills. Therefore, we suggest patient-specific VPH models that are composed by registering the general mesh-based models with patient voxel data-based recordings. Specifically, the pelvis region has been focused for the support of the femoral nerve block. The processing pipeline is composed of different freely available toolboxes such as MatLab, the open Simulation framework (SOFA), and MeshLab. The approach of Gilles is applied for mesh-to-voxel registration. Personalized VPH models include anatomical as well as mechanical properties of the tissues. Two commercial VPH models (Zygote and Anatomium) were used together with 34 MRI data sets. Results are presented for the skin surface and pelvic bones. Future work will extend the registration procedure to cope with all model tissue (i.e., skin, muscle, bone, vessel, nerve, fascia) in a one-step procedure and extrapolating the personalized models to body regions actually being out of the captured field of view.

  5. Prediction of Surface and pH-Specific Binding of Peptides to Metal and Oxide Nanoparticles

    NASA Astrophysics Data System (ADS)

    Heinz, Hendrik; Lin, Tzu-Jen; Emami, Fateme Sadat; Ramezani-Dakhel, Hadi; Naik, Rajesh; Knecht, Marc; Perry, Carole C.; Huang, Yu

    2015-03-01

    The mechanism of specific peptide adsorption onto metallic and oxidic nanostructures has been elucidated in atomic resolution using novel force fields and surface models in comparison to measurements. As an example, variations in peptide adsorption on Pd and Pt nanoparticles depending on shape, size, and location of peptides on specific bounding facets are explained. Accurate computational predictions of reaction rates in C-C coupling reactions using particle models derived from HE-XRD and PDF data illustrate the utility of computational methods for the rational design of new catalysts. On oxidic nanoparticles such as silica and apatites, it is revealed how changes in pH lead to similarity scores of attracted peptides lower than 20%, supported by appropriate model surfaces and data from adsorption isotherms. The results demonstrate how new computational methods can support the design of nanoparticle carriers for drug release and the understanding of calcification mechanisms in the human body.

  6. Mesoporous carbon-supported Pd nanoparticles with high specific surface area for cyclohexene hydrogenation: Outstanding catalytic activity of NaOH-treated catalysts

    NASA Astrophysics Data System (ADS)

    Puskás, R.; Varga, T.; Grósz, A.; Sápi, A.; Oszkó, A.; Kukovecz, Á.; Kónya, Z.

    2016-06-01

    Extremely high specific surface area mesoporous carbon-supported Pd nanoparticle catalysts were prepared with both impregnation and polyol-based sol methods. The silica template used for the synthesis of mesoporous carbon was removed by both NaOH and HF etching. Pd/mesoporous carbon catalysts synthesized with the impregnation method has as high specific surface area as 2250 m2/g. In case of NaOH-etched impregnated samples, the turnover frequency of cyclohexene hydrogenation to cyclohexane at 313 K was obtained 14 molecules • site- 1 • s- 1. The specific surface area of HF-etched samples was higher compared to NaOH-etched samples. However, catalytic activity was 3-6 times higher on NaOH-etched samples compared to HF-etched samples, which can be attributed to the presence of sodium and surface hydroxylgroups of the catalysts etched with NaOH solution.

  7. Structural and surface properties of CuO-ZnO-Cr{sub 2}O{sub 3} catalysts and their relationship with selectivity to higher alcohol synthesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campos-Martin, J.M.; Fierro, J.L.G.; Guerrero-Ruiz, A.

    1995-10-01

    A series of copper-zinc-chromium catalysts of different compositions and calcination temperatures has been prepared, characterized by several techniques (BET specific surface area, XRD, gravimetric TPR, TPD-CO, and XPS), and tested under high alcohol synthesis (HAS) conditions. CO hydrogenation was carried out at reaction temperatures of 523-598 K and 50 bar total pressure. The influence of catalyst composition, calcination temperature, and surface characteristics on the HAS selectivity was studied. The optimum HAS yields were found in the low Cr content region, but chromium was needed. Although chromium oxide does not seem to be involved in the catalytic site, its presence inmore » the catalyst composition is essential, owing to the larger specific surfaces and catalyst stability obtained at the highest reaction temperatures. For low Cr content composition, the temperature-programmed reduction (TPR) profiles were shifted to higher temperatures and simultaneously larger CO{sub 2} amounts were found in the temperature-programmed desorption profiles of adsorbed CO (TPD-CO). Photoelectron spectra (XPS) revealed that the oxidation state of copper is Cu{sup 2+} in the calcined catalysts and Cu{sup O} in the reduced ones; Cu{sup +} was only stabilized in a CuCr{sub 2}O{sub 4} spinel in the Cr-rich catalysts. These features derived from catalyst characterization are discussed in the framework of the catalytic behaviour for HAS synthesis. 53 refs., 7 figs., 4 tabs.« less

  8. Discussion about the use of the volume specific surface area (VSSA) as a criterion to identify nanomaterials according to the EU definition. Part two: experimental approach.

    PubMed

    Lecloux, André J; Atluri, Rambabu; Kolen'ko, Yury V; Deepak, Francis Leonard

    2017-10-12

    The first part of this study was dedicated to the modelling of the influence of particle shape, porosity and particle size distribution on the volume specific surface area (VSSA) values in order to check the applicability of this concept to the identification of nanomaterials according to the European Commission Recommendation. In this second part, experimental VSSA values are obtained for various samples from nitrogen adsorption isotherms and these values were used as a screening tool to identify and classify nanomaterials. These identification results are compared to the identification based on the 50% of particles with a size below 100 nm criterion applied to the experimental particle size distributions obtained by analysis of electron microscopy images on the same materials. It is concluded that the experimental VSSA values are able to identify nanomaterials, without false negative identification, if they have a mono-modal particle size, if the adsorption data cover the relative pressure range from 0.001 to 0.65 and if a simple, qualitative image of the particles by transmission or scanning electron microscopy is available to define their shape. The experimental conditions to obtain reliable adsorption data as well as the way to analyze the adsorption isotherms are described and discussed in some detail in order to help the reader in using the experimental VSSA criterion. To obtain the experimental VSSA values, the BET surface area can be used for non-porous particles, but for porous, nanostructured or coated nanoparticles, only the external surface of the particles, obtained by a modified t-plot approach, should be considered to determine the experimental VSSA and to avoid false positive identification of nanomaterials, only the external surface area being related to the particle size. Finally, the availability of experimental VSSA values together with particle size distributions obtained by electron microscopy gave the opportunity to check the

  9. Evolution of the Specific Surface Area of Snow in a High Temperature Gradient Metamorphism

    NASA Astrophysics Data System (ADS)

    Wang, X.; Baker, I.

    2014-12-01

    The structural evolution of low-density snow under a high temperature gradient over a short period usually takes place in the surface layers during diurnal recrystallization or on a clear, cold night. To relate snow microstructures with their thermal properties, we combined X-ray computed microtomography (micro-CT) observations with numerical simulations. Different types of snow were tested over a large range of TGs (100 K m-1- 500 K m-1). The Specific Surface Area (SSA) was used to characterize the temperature gradient metamorphism (TGM). The magnitude of the temperature gradient and the initial snow type both influence the evolution of SSA. The SSA evolution under TGM was dominated by grain growth and the formation of complex surfaces. Fresh snow experienced a logarithmic decrease of SSA with time, a feature been observed previously by others [Calonne et al., 2014; Schneebeli and Sokratov, 2004; Taillandier et al., 2007]. However, for initial rounded and connected snow structures, the SSA will increase during TGM. Understanding the SSA increase is important in order to predict the enhanced uptake of chemical species by snow or increase in snow albedo. Calonne, N., F. Flin, C. Geindreau, B. Lesaffre, and S. Rolland du Roscoat (2014), Study of a temperature gradient metamorphism of snow from 3-D images: time evolution of microstructures, physical properties and their associated anisotropy, The Cryosphere Discussions, 8, 1407-1451, doi:10.5194/tcd-8-1407-2014. Schneebeli, M., and S. A. Sokratov (2004), Tomography of temperature gradient metamorphism of snow and associated changes in heat conductivity, Hydrological Processes, 18(18), 3655-3665, doi:10.1002/hyp.5800. Taillandier, A. S., F. Domine, W. R. Simpson, M. Sturm, and T. A. Douglas (2007), Rate of decrease of the specific surface area of dry snow: Isothermal and temperature gradient conditions, Journal of Geophysical Research: Earth Surface (2003-2012), 112(F3), doi: 10.1029/2006JF000514.

  10. A patient-specific aortic valve model based on moving resistive immersed implicit surfaces.

    PubMed

    Fedele, Marco; Faggiano, Elena; Dedè, Luca; Quarteroni, Alfio

    2017-10-01

    In this paper, we propose a full computational framework to simulate the hemodynamics in the aorta including the valve. Closed and open valve surfaces, as well as the lumen aorta, are reconstructed directly from medical images using new ad hoc algorithms, allowing a patient-specific simulation. The fluid dynamics problem that accounts from the movement of the valve is solved by a new 3D-0D fluid-structure interaction model in which the valve surface is implicitly represented through level set functions, yielding, in the Navier-Stokes equations, a resistive penalization term enforcing the blood to adhere to the valve leaflets. The dynamics of the valve between its closed and open position is modeled using a reduced geometric 0D model. At the discrete level, a finite element formulation is used and the SUPG stabilization is extended to include the resistive term in the Navier-Stokes equations. Then, after time discretization, the 3D fluid and 0D valve models are coupled through a staggered approach. This computational framework, applied to a patient-specific geometry and data, allows to simulate the movement of the valve, the sharp pressure jump occurring across the leaflets, and the blood flow pattern inside the aorta.

  11. Dynamic characterisation of the specific surface area for fracture networks

    NASA Astrophysics Data System (ADS)

    Cvetkovic, V.

    2017-12-01

    One important application of chemical transport is geological disposal of high-level nuclear waste for which crystalline rock is a prime candidate for instance in Scandinavia. Interconnected heterogeneous fractures of sparsely fractured rock such as granite, act as conduits for transport of dissolved tracers. Fluid flow is known to be highly channelized in such rocks. Channels imply narrow flow paths, adjacent to essentially stagnant water in the fracture and/or the rock matrix. Tracers are transported along channelised flow paths and retained by minerals and/or stagnant water, depending on their sorption properties; this mechanism is critical for rocks to act as a barrier and ultimately provide safety for a geological repository. The sorbing tracers are retained by diffusion and sorption on mineral surfaces, whereas non-sorbing tracers can be retained only by diffusion into stagnant water of fractures. The retention and transport properties of a sparsely fractured rock will primarily depend on the specific surface area (SSA) of the fracture network which is determined by the heterogeneous structure and flow. The main challenge when characterising SSA on the field-scale is its dependence on the flow dynamics. We first define SSA as a physical quantity and clarify its importance for chemical transport. A methodology for dynamic characterisation of SSA in fracture networks is proposed that relies on three sets of data: i) Flow rate data as obtained by a flow logging procedure; ii) transmissivity data as obtained by pumping tests; iii) fracture network data as obtained from outcrop and geophysical observations. The proposed methodology utilises these data directly as well as indirectly through flow and particle tracking simulations in three-dimensional discrete fracture networks. The methodology is exemplified using specific data from the Swedish site Laxemar. The potential impact of uncertainties is of particular significance and is illustrated for radionuclide

  12. Kinetics of gibbsite dissolution under low ionic strength conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ganor, J.; Mogollon, J.L.; Lasaga, A.C.

    1999-06-01

    Experiments measuring synthetic gibbsite dissolution rates were carried out using both a stirred-flow-through reactor and a column reactor at 25 C, and pH range of 2.5--4.1. All experiments were conducted under far from equilibrium conditions ({Delta}G < {minus}1.1 kcal/mole). The experiments were performed with perchloric acid under relatively low (and variable) ionic strength conditions. An excellent agreement was found between the results of the well-mixed flow-through experiments and those of the (nonmixed) column experiments. This agreement shows that the gibbsite dissolution rate is independent of the stirring rate and therefore supports the conclusion of Bloom and Erich (1987) that gibbsitemore » dissolution reaction is surface controlled and not diffusion controlled. The Brunauer-Emmett-Teller (BET) surface area of the gibbsite increased during the flow-through experiments, while in the column experiments no significant change in surface area was observed. The significant differences in the BET surface area between the column experiments and the flow-through experiments, and the excellent agreement between the rates obtained by both methods, enable the authors to justify the substitution of the BET surface area for the reactive surface area. The dissolution rate of gibbsite varied as a function of the perchloric acid concentration. The authors interpret the gibbsite dissolution rate as a result of a combined effect of proton catalysis and perchlorate inhibition. Following the theoretical study of Ganor and Lasaga (1998) they propose specific reaction mechanisms for the gibbsite dissolution in the presence of perchloric acid. The mathematical predictions of two of these reaction mechanisms adequately describe the experimental data.« less

  13. Interfacial Interaction in Anodic Aluminum Oxide Templates Modifies Morphology, Surface Area, and Crystallization of Polyamide-6 Nanofibers.

    PubMed

    Xue, Junhui; Xu, Yizhuang; Jin, Zhaoxia

    2016-03-08

    Here, we demonstrated that, when the precipitation process of polyamide-6 (PA6) solution happens in cylindrical channels of an anodized aluminum oxide membrane (AAO), interface interactions between a solid surface, solvent, non-solvent, and PA6 will influence the obtained polymer nanostructures, resulting in complex morphologies, increased surface area, and crystallization changes. With the enhancing interaction of PA6 and the AAO surface, the morphology of PA6 nanostructures changes from solid nanofibers, mesoporous, to bamboo-like, while at the same time, metastable γ-phase domains increase in these PA6 nanostructures. Brunauer-Emmett-Teller (BET) surface areas of solid, bamboo-like, and mesoporous PA6 nanofibers rise from 16, 20.9, to 25 m(2)/g. This study shows that interfacial interaction in AAO template fabrication can be used in manipulating the morphology and crystallization of one-dimensional polymer nanostructures. It also provides us a simple and novel method to create porous PA6 nanofibers with a large surface area.

  14. Stability analysis of the high poloidal bet scenario on DIII-Dtowards operation athigher plasma current

    NASA Astrophysics Data System (ADS)

    Guo, W. F.; Gong, X. Z.; Huang, J.; Ren, Q. L.; Qian, J. P.; Ding, S. Y.; Pan, C. K.; Li, G. Q.; Xia, T. Y.; Garofalo, A. M.; Lao, L.; Hyatt, A.; Ferron, J.; Meneghini, O.; Liu, Y. Q.; McClenaghan, J.; Holcomb, C. T.

    2017-10-01

    The high poloidal beta scenario with plasma current IP 600 kA and large-radius internal transport barrier (ITB) on DIII-D is subject to n =1 MHD kink modes when the current profile becomes very broad at internal inductance values li 0.5-0.6. It is desirable to extend this scenario to higer plasma current ( 1 MA) for highernormalized fusionperformance. However, higher current at constant normalized beta, ?N 3, would reducethe poloidal bet, ?P, below the threshold for ITB sustainment, observed at ?P 1.9. Thus, to avoid loss of the IT, ?N?? must be increased together with IP while avoiding the kink instability. MHD analysis is presented that explains possible paths to high ?N stability limit for the kink mode in tis scenario. Work supported by National Magnetic Confinement Fusion Program of Chin under 2015GB110001 and 2015GB102000 - National Natural Science Foundation of China under Grant No. 1147521 and by US DOE under DE-FC02-04ER54698.

  15. Optimization of orodispersible and conventional tablets using simplex lattice design: Relationship among excipients and banana extract.

    PubMed

    Duangjit, Sureewan; Kraisit, Pakorn

    2018-08-01

    The objective of this study was focused on the optimization of the pharmaceutical excipients and banana extract in the preparation of orally disintegrating banana extract tablets (OD-BET) and conventional banana extract tablets (CO-BET) using a simplex lattice design. Various ratios of banana extract (BE), dibasic calcium phosphate (DCP) and microcrystalline cellulose (MCC) were used to prepare banana extract tablets (BET). The results indicated that the optimal OD-BET and CO-BET consisted of BE: DCP: MCC at 10.0, 88.8, 1.2, 10.0, 83.8: and 6.2, respectively. AFM demonstrated that the surface of BET with BE + MCC was smooth and compacted when compared to BET with BE + DCP + MCC and BE + DCP. FTIR and XRD showed a correlation in the results and indicated that no interaction of each ingredient occurred in the process of BET formulation. Therefore, the experimental design is potentially useful in formulated OD-BET and CO-BET by using only one design simultaneously. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Inhibition of bromodomain and extra-terminal (BET) proteins increases NKG2D ligand MICA expression and sensitivity to NK cell-mediated cytotoxicity in multiple myeloma cells: role of cMYC-IRF4-miR-125b interplay.

    PubMed

    Abruzzese, Maria Pia; Bilotta, Maria Teresa; Fionda, Cinzia; Zingoni, Alessandra; Soriani, Alessandra; Vulpis, Elisabetta; Borrelli, Cristiana; Zitti, Beatrice; Petrucci, Maria Teresa; Ricciardi, Maria Rosaria; Molfetta, Rosa; Paolini, Rossella; Santoni, Angela; Cippitelli, Marco

    2016-12-01

    Anti-cancer immune responses may contribute to the control of tumors after conventional chemotherapy, and different observations have indicated that chemotherapeutic agents can induce immune responses resulting in cancer cell death and immune-stimulatory side effects. Increasing experimental and clinical evidence highlight the importance of natural killer (NK) cells in immune responses toward multiple myeloma (MM), and combination therapies able to enhance the activity of NK cells against MM are showing promise in treating this hematologic cancer. The epigenetic readers of acetylated histones bromodomain and extra-terminal (BET) proteins are critical regulators of gene expression. In cancer, they can upregulate transcription of key oncogenes such as cMYC, IRF4, and BCL-2. In addition, the activity of these proteins can regulate the expression of osteoclastogenic cytokines during cancer progression. Here, we investigated the effect of BET bromodomain protein inhibition, on the expression of NK cell-activating ligands in MM cells. Five MM cell lines [SKO-007(J3), U266, RPMI-8226, ARP-1, JJN3] and CD138 + MM cells isolated from MM patients were used to investigate the activity of BET bromodomain inhibitors (BETi) (JQ1 and I-BET151) and of the selective BRD4-degrader proteolysis targeting chimera (PROTAC) (ARV-825), on the expression and function of several NK cell-activating ligands (NKG2DLs and DNAM-1Ls), using flow cytometry, real-time PCR, transient transfections, and degranulation assays. Our results indicate that inhibition of BET proteins via small molecule inhibitors or their degradation via a hetero-bifunctional PROTAC probe can enhance the expression of MICA, a ligand of the NKG2D receptor, in human MM cell lines and primary malignant plasma cells, rendering myeloma cells more efficient to activate NK cell degranulation. Noteworthy, similar results were obtained using selective CBP/EP300 bromodomain inhibition. Mechanistically, we found that BETi

  17. Resistance to BET Inhibitor Leads to Alternative Therapeutic Vulnerabilities in Castration-Resistant Prostate Cancer.

    PubMed

    Pawar, Aishwarya; Gollavilli, Paradesi Naidu; Wang, Shaomeng; Asangani, Irfan A

    2018-02-27

    BRD4 plays a major role in the transcription networks orchestrated by androgen receptor (AR) in castration-resistant prostate cancer (CRPC). Several BET inhibitors (BETi) that displace BRD4 from chromatin are being evaluated in clinical trials for CRPC. Here, we describe mechanisms of acquired resistance to BETi that are amenable to targeted therapies in CRPC. BETi-resistant CRPC cells displayed cross-resistance to a variety of BETi in the absence of gatekeeper mutations, exhibited reduced chromatin-bound BRD4, and were less sensitive to BRD4 degraders/knockdown, suggesting a BRD4-independent transcription program. Transcriptomic analysis revealed reactivation of AR signaling due to CDK9-mediated phosphorylation of AR, resulting in sensitivity to CDK9 inhibitors and enzalutamide. Additionally, increased DNA damage associated with PRC2-mediated transcriptional silencing of DDR genes was observed, leading to PARP inhibitor sensitivity. Collectively, our results identify the therapeutic limitation of BETi as a monotherapy; however, our BETi resistance data suggest unique opportunities for combination therapies in treating CRPC. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  18. Enhancement of the surface methane hydrate-bearing layer based on the specific microorganisms form deep seabed sediment in Japan Sea.

    NASA Astrophysics Data System (ADS)

    Hata, T.; Yoneda, J.; Yamamoto, K.

    2017-12-01

    A methane hydrate-bearing layer located near the Japan Sea has been investigated as a new potential energy resource. In this study examined the feasibility of the seabed surface sediment strength located in the Japan Sea improvement technologies for enhancing microbial induced carbonate precipitation (MICP) process. First, the authors cultivated the specific urease production bacterium culture medium from this surface methane hydrate-bearing layer in the seabed (-600m depth) of Japan Sea. After that, two types of the laboratory test (consolidated-drained triaxial tests) were conducted using this specific culture medium from the seabed in the Japan Sea near the Toyama Prefecture and high urease activities bacterium named Bacillus pasteurii. The main outcomes of this research are as follows. 1) Specific culture medium focused on the urease production bacterium can enhancement of the urease activities from the methane hydrate-bearing layer near the Japan Sea side, 2) This specific culture medium can be enhancement of the surface layer strength, 3) The microbial induced carbonate precipitation process can increase the particle size compared to that of the original particles coating the calcite layer surface, 4) The mechanism for increasing the soil strength is based on the addition of cohesion like a cement stabilized soil.

  19. Heteroatom Polymer-Derived 3D High-Surface-Area and Mesoporous Graphene Sheet-Like Carbon for Supercapacitors.

    PubMed

    Sheng, Haiyang; Wei, Min; D'Aloia, Alyssa; Wu, Gang

    2016-11-09

    Current supercapacitors suffer from low energy density mainly due to the high degree of microporosity and insufficient hydrophilicity of their carbon electrodes. Development of a supercapacitor capable of simultaneously storing as much energy as a battery, along with providing sufficient power and long cycle stability would be valued for energy storage applications and innovations. Differing from commonly studied reduced graphene oxides, in this work we identified an inexpensive heteroatom polymer (polyaniline-PANI) as a carbon/nitrogen precursor, and applied a controlled thermal treatment at elevated temperature to convert PANI into 3D high-surface-area graphene-sheet-like carbon materials. During the carbonization process, various transition metals including Fe, Co, and Ni were added, which play critical roles in both catalyzing the graphitization and serving as pore forming agents. Factors including post-treatments, heating temperatures, and types of metal were found crucial for achieving enhanced capacitance performance on resulting carbon materials. Using FeCl 3 as precursor along with optimal heating temperature 1000 °C and mixed acid treatment (HCl+HNO 3 ), the highest Brunauer-Emmett-Teller (BET) surface area of 1645 m 2 g -1 was achieved on the mesopore dominant graphene-sheet-like carbon materials. The unique morphologies featured with high-surface areas, dominant mesopores, proper nitrogen doping, and 3D graphene-like structures correspond to remarkably enhanced electrochemical specific capacitance up to 478 Fg -1 in 1.0 M KOH at a scan rate of 5 mV s -1 . Furthermore, in a real two-electrode system of a symmetric supercapacitor, a specific capacitance of 235 Fg -1 using Nafion binder is obtained under a current density of 1 Ag -1 by galvanostatic charge-discharge tests in 6.0 M KOH. Long-term cycle stability up to 5000 cycles by using PVDF binder in electrode was systematically evaluated as a function of types of metals and current densities.

  20. Specific surface to evaluate the efficiencies of milling and pretreatment of wood for enzymatic saccharification

    Treesearch

    Junyong Zhu; G.S. Wang; X.J. Pan; Roland Gleisner

    2009-01-01

    Sieving methods have been almost exclusively used for feedstock size-reduction characterization in the biomass refining literature. This study demonstrates a methodology to properly characterize specific surface of biomass substrates through two dimensional measurement of each fiber of the substrate using a wet imaging technique. The methodology provides more...

  1. Dual transcriptome sequencing reveals resistance of TLR4 ligand-activated bone marrow-derived macrophages to inflammation mediated by the BET inhibitor JQ1

    PubMed Central

    Das, Amitabh; Chai, Jin Choul; Yang, Chul-su; Lee, Young Seek; Das, Nando Dulal; Jung, Kyoung Hwa; Chai, Young Gyu

    2015-01-01

    Persistent macrophage activation is associated with the expression of various pro-inflammatory genes, cytokines and chemokines, which may initiate or amplify inflammatory disorders. A novel synthetic BET inhibitor, JQ1, was proven to exert immunosuppressive activities in macrophages. However, a genome-wide search for JQ1 molecular targets has not been undertaken. The present study aimed at evaluating the anti-inflammatory function and underlying genes that are targeted by JQ1 in LPS-stimulated primary bone marrow-derived macrophages (BMDMs) using global transcriptomic RNA sequencing and quantitative real-time PCR. Among the annotated genes, transcriptional sequencing of BMDMs that were treated with JQ1 revealed a selective effect on LPS-induced gene expression in which the induction of cytokines/chemokines, interferon-stimulated genes, and prominent (transcription factors) TFs was suppressed. Additionally, we found that JQ1 reduced the expression of previously unidentified genes that are important in inflammation. Importantly, these inflammatory genes were not affected by JQ1 treatment alone. Furthermore, we confirmed that JQ1 reduced cytokines/chemokines in the supernatants of LPS treated BMDMs. Moreover, the biological pathways and gene ontology of the differentially expressed genes were determined in the JQ1 treatment of BMDMs. These unprecedented results suggest that the BET inhibitor JQ1 is a candidate for the prevention or therapeutic treatment of inflammatory disorders. PMID:26582142

  2. Expression of an endotoxin-free S-layer/allergen fusion protein in gram-positive Bacillus subtilis 1012 for the potential application as vaccines for immunotherapy of atopic allergy

    PubMed Central

    2011-01-01

    Background Genetic fusion of the major birch pollen allergen (Bet v1) to bacterial surface-(S)-layer proteins resulted in recombinant proteins exhibiting reduced allergenicity as well as immunomodulatory capacity. Thus, S-layer/allergen fusion proteins were considered as suitable carriers for new immunotherapeutical vaccines for treatment of Type I hypersensitivity. Up to now, endotoxin contamination of the fusion protein which occurred after isolation from the gram-negative expression host E. coli had to be removed by an expensive and time consuming procedure. In the present study, in order to achieve expression of pyrogen-free, recombinant S-layer/allergen fusion protein and to study the secretion of a protein capable to self-assemble, the S-layer/allergen fusion protein rSbpA/Bet v1 was produced in the gram-positive organism Bacillus subtilis 1012. Results The chimaeric gene encoding the S-layer protein SbpA of Lysinibacillus sphaericus CCM 2177 as well as Bet v1 was cloned and expressed in B. subtilis 1012. For that purpose, the E. coli-B. subtilis shuttle vectors pHT01 for expression in the B. subtilis cytoplasm and pHT43 for secretion of the recombinant fusion protein into the culture medium were used. As shown by western blot analysis, immediately after induction of expression, B. subtilis 1012 was able to secret rSbpA/Bet v1 mediated by the signal peptide amyQ of Bacillus amyloliquefaciens. Electron microscopical investigation of the culture medium revealed that the secreted fusion protein was able to form self-assembly products in suspension but did not recrystallize on the surface of the B. subtilis cells. The specific binding mechanism between the N-terminus of the S-layer protein and a secondary cell wall polymer (SCWP), located in the peptidoglycan-containing sacculi of Ly. sphaericus CCM 2177, could be used for isolation and purification of the secreted fusion protein from the culture medium. Immune reactivity of rSbpA/Bet v1 could be demonstrated in

  3. Bdf1 Bromodomains Are Essential for Meiosis and the Expression of Meiotic-Specific Genes

    PubMed Central

    Perot, Jonathan; Arlotto, Marie; Mietton, Flore; Boland, Anne; Deleuze, Jean-François; Ferro, Myriam; Govin, Jérôme

    2017-01-01

    Bromodomain and Extra-terminal motif (BET) proteins play a central role in transcription regulation and chromatin signalling pathways. They are present in unicellular eukaryotes and in this study, the role of the BET protein Bdf1 has been explored in Saccharomyces cerevisiae. Mutation of Bdf1 bromodomains revealed defects on both the formation of spores and the meiotic progression, blocking cells at the exit from prophase, before the first meiotic division. This phenotype is associated with a massive deregulation of the transcription of meiotic genes and Bdf1 bromodomains are required for appropriate expression of the key meiotic transcription factor NDT80 and almost all the Ndt80-inducible genes, including APC complex components. Bdf1 notably accumulates on the promoter of Ndt80 and its recruitment is dependent on Bdf1 bromodomains. In addition, the ectopic expression of NDT80 during meiosis partially bypasses this dependency. Finally, purification of Bdf1 partners identified two independent complexes with Bdf2 or the SWR complex, neither of which was required to complete sporulation. Taken together, our results unveil a new role for Bdf1 –working independently from its predominant protein partners Bdf2 and the SWR1 complex–as a regulator of meiosis-specific genes. PMID:28068333

  4. Changes in cell surface structure by viral transformation studied by binding of lectins differing in sugar specificity.

    PubMed

    Tsuda, M; Kurokawa, T; Takeuchi, M; Sugino, Y

    1975-10-01

    Changes in cell surface structure by viral transformation were studied by examining changes in the binding of various lectins differing in carbohydrate specificities. Binding of lectins was assayed directly using cells grown in coverslips. The following 125I-lectins were used: Concanavalin-A (specific for glucose and mannose), wheat germ agglutinin (specific for N-acetylglucosamine), castor bean agglutinin (specific for galactose), Wistaria floribunda agglutinin (specific for N-acetylgalactosamine), and soybean agglutinin (specific for N-acetyl-galactosamine). Cells for a clone, SS7, transformed by bovine adenovirus type-3, were found to bind 5 to 6 times more Wistaria floribunda agglutinin than the normal counterpart cells (clone C31, from C3H mouse kidney). In contrast, the binding of soybean agglutinin, which has a sugar specificity similar to Wistaria floribunda agglutinin, to normal and transformed cells was similar. The binding of wheat germ agglutinin and castor bean agglutinin, respectively, to normal and transformed cells was also similar. However, normal cells bound twice as much concanavalin-A as transformed cells. Only half as much Wistaria floribunda agglutinin was bound to transformed cells when they had been dispersed with EDTA. These changes in the number of lectin binding sites on transformation are thought to reflect alteration of the cell surface structure. The amount of lectins bound per cell decreased with increase in cell density, especially in the case of binding of Wistaria floribunda agglutinin to normal cells.

  5. Amino acid specificity of fibers of the facial/trigeminal complex innervating the maxillary barbel in the Japanese sea catfish, Plotosus japonicus.

    PubMed

    Caprio, John; Shimohara, Mami; Marui, Takayuki; Kohbara, Jun; Harada, Shuitsu; Kiyohara, Sadao

    2015-12-01

    The Japanese sea catfish, Plotosus japonicus, possesses taste and solitary chemoreceptor cells (SCCs) located on the external body surface that detect specific water-soluble substances. Here, we identify two major fiber types of the facial/trigeminal complex that transmit amino acid information to the medulla. Both single and few fiber preparations respond to amino acid stimulation in the 0.1 μM to mM range. One fiber type responds best to glycine and l-alanine (i.e. Gly/Ala fibers) whereas the other fiber type is best stimulated by l-proline and glycine betaine (hereafter referred to only as betaine) (i.e. Pro/Bet fibers). We demonstrate that betaine, which does not alter the pH of the seawater and therefore does not activate the animals' highly sensitive pH sensors (Caprio et al., Science 344:1154-1156, 2014), is sufficient to elicit appetitive food search behavior. We further show that the amino acid specificity of fibers of the facial/trigeminal complex in P. japonicus is different from that in Ariopsis felis (Michel and Caprio, J. Neurophysiol. 66:247-260, 1991; Michel et al., J. Comp. Physiol. A. 172:129-138, 1993), a representative member of the only other family (Ariidae) of extant marine catfishes. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Adsorption of cadmium by activated carbon cloth: influence of surface oxidation and solution pH.

    PubMed

    Rangel-Mendez, J R; Streat, M

    2002-03-01

    The surface of activated carbon cloth (ACC), based on polyacrylonitrile fibre as a precursor, was oxidised using nitric acid, ozone and electrochemical oxidation to enhance cadmium ion exchange capacity. Modified adsorbents were physically and chemically characterised by pH titration, direct titration, X-ray photoelectron spectroscopy, elemental analysis, surface area and porosimetry, and scanning electron microscopy. BET surface area decreased after oxidation, however, the total ion exchange capacity increased by a factor of approximately 3.5 compared to the commercial as-received ACC. A very significant increase in cadmium uptake, by a factor of 13, was observed for the electrochemically oxidised ACC. Equilibrium sorption isotherms were determined at pH 4, 5 and 6 and these showed that cadmium uptake increased with increasing pH. There was clear evidence of physical damage to ozone-oxidised fibre, however, acid and electrochemically oxidised samples were completely stable.

  7. Wilms tumor gene product: sensitive and contextually specific marker of serous carcinomas of ovarian surface epithelial origin.

    PubMed

    Hwang, Harry; Quenneville, Louise; Yaziji, Hadi; Gown, Allen M

    2004-06-01

    Carcinomas of ovarian surface epithelial origin can arise from, and often present at, extraovarian sites. There are few available markers for the positive identification of carcinomas of ovarian surface epithelial origin, which might aid in distinguishing them from metastatic carcinomas, such as of breast, colon, or lung origin. Recently, the Wilms tumor gene product (WT-1) has been shown to be expressed in ovarian surface and mesothelial epithelium. We tested the hypothesis that WT-1 would be a sensitive and specific marker of ovarian surface epithelium carcinomas. An archived series of 116 ovarian carcinomas (57 serous [43 ovarian, 14 extraovarian], 31 mucinous, 15 clear cell, 13 endometrioid), 118 breast carcinomas, 46 colonic carcinomas, and 45 nonsmall cell lung cancers were selected. A polyclonal antibody to the WT-1 gene product was applied to deparaffinized, formalin-fixed tissue sections after epitope retrieval. Fifty-two of 57 (93%) serous carcinomas of ovarian surface epithelial origin were WT-1-positive, in a nuclear pattern, with virtually all the tumor cell population positive in the majority of cases. None of the mucinous, clear cell, or endometrioid ovarian cancers were positive, and only 8 of 118 breast, 0 of 46 colonic, and 0 of 45 lung nonsmall cell carcinomas were WT-1-positive. These findings demonstrate that WT-1 is a highly sensitive and specific marker of serous carcinomas of ovarian surface epithelial origin (both ovarian and extraovarian). These results also contradict recent reports demonstrating WT-1 expression in both breast and lung carcinomas.

  8. 3-D surface reconstruction of patient specific anatomic data using a pre-specified number of polygons.

    PubMed

    Aharon, S; Robb, R A

    1997-01-01

    Virtual reality environments provide highly interactive, natural control of the visualization process, significantly enhancing the scientific value of the data produced by medical imaging systems. Due to the computational and real time display update requirements of virtual reality interfaces, however, the complexity of organ and tissue surfaces which can be displayed is limited. In this paper, we present a new algorithm for the production of a polygonal surface containing a pre-specified number of polygons from patient or subject specific volumetric image data. The advantage of this new algorithm is that it effectively tiles complex structures with a specified number of polygons selected to optimize the trade-off between surface detail and real-time display rates.

  9. Molecular analysis of the role of osmolyte transporters opuCA and betL in Listeria monocytogenes after cold and freezing stress.

    PubMed

    Miladi, Hanene; Elabed, Hamouda; Ben Slama, Rihab; Rhim, Amel; Bakhrouf, Amina

    2017-03-01

    Listeria monocytogenes is a food-borne pathogen of humans and other animals. The striking ability to survive several stresses usually used for food preservation makes L. monocytogenes one of the biggest concerns to the food industry. This ubiquity can be partly explained by the ability of the organism to grow and persist at very low temperatures, a consequence of its ability to accumulate cryoprotective compound called osmolytes. A quantitative RT-PCR assay was used to measure mRNA transcript accumulation for the stress response genes opuCA and betL (encoding carnitine and betaine transporters, respectively) and the housekeeping gene 16S rRNA. Assays were conducted on mid-exponential phase L. monocytogenes cells exposed to conditions reflecting cold and freezing stress, conditions usually used to preserve foods. We showed that expression of the two cold-adapted genes encoded the transporters of the cryoprotectants carnitine and betaine in ATCC 19115 and the food-isolated L. monocytogenes S1 is induced after cold and freezing stress exposure. Furthermore, transcriptional analysis of the genes encoding opuCA and betL revealed that each transporter is induced to different degrees upon cold shock of L. monocytogenes ATCC 19115 and S1. Our results confirm an increase in carnitine uptake at low temperatures more than in betaine after cold-shocked temperature compared to the non-stress control treatment. It was concluded the use of carnitine and betaine as cryoprotectants is essential for rapid induction of the tested stress response under conditions typically encountered during food preservation.

  10. Digital Rectal Examination and Balloon Expulsion Test in the Study of Defecatory Disorders: Are They Suitable as Screening or Excluding Tests?

    PubMed

    Caetano, Ana C; Santa-Cruz, André; Rolanda, Carla

    2016-01-01

    Background . Rome III criteria add physiological criteria to symptom-based criteria of chronic constipation (CC) for the diagnosis of defecatory disorders (DD). However, a gold-standard test is still lacking and physiological examination is expensive and time-consuming. Aim . Evaluate the usefulness of two low-cost tests-digital rectal examination (DRE) and balloon expulsion test (BET)-as screening or excluding tests of DD. Methods . We performed a systematic search in PUBMED and MEDLINE. We selected studies where constipated patients were evaluated by DRE or BET. Heterogeneity was assessed and random effect models were used to calculate the sensitivity, specificity, and negative predictive value (NPV) of the DRE and the BET. Results . Thirteen studies evaluating BET and four studies evaluating DRE (2329 patients) were selected. High heterogeneity ( I 2 > 80%) among studies was demonstrated. The studies evaluating the BET showed a sensitivity and specificity of 67% and 80%, respectively. Regarding the DRE, a sensitivity of 80% and specificity of 84% were calculated. NPV of 72% for the BET and NPV of 64% for the DRE were estimated. The sensitivity and specificity were similar when we restrict the analysis to studies using Rome criteria to define CC. The BET seems to perform better when a cut-off time of 2 minutes is used and when it is compared with a combination of physiological tests. Considering the DRE, strict criteria seem to improve the sensitivity but not the specificity of the test. Conclusion . Neither of the low-cost tests seems suitable for screening or excluding DD.

  11. Enhanced capture of elemental mercury by bamboo-based sorbents.

    PubMed

    Tan, Zengqiang; Xiang, Jun; Su, Sheng; Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong

    2012-11-15

    To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO2 on gas-phase Hg0 adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents' BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 °C and 180 °C. The presence of NO or SO2 could inhibit Hg0 capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Reactivity of NO2 and CO2 with hardened cement paste containing activated carbon

    NASA Astrophysics Data System (ADS)

    Horgnies, M.; Dubois-Brugger, I.; Krou, N. J.; Batonneau-Gener, I.; Belin, T.; Mignard, S.

    2015-07-01

    The development of building materials to reduce the concentration of NO2 is growing interest in a world where the air quality in urban areas is affected by the car traffic. The main binder in concrete is the cement paste that is partly composed of calcium hydroxide. This alkaline hydrate composing the hardened cement paste shows a high BET surface area (close to 100 m2.g-1) and can absorb low-concentrations of NO2. However, the presence of CO2 in the atmosphere limits the de-polluting effect of reference cement paste, mainly due to carbonation of the alkaline hydrates (reaction leading to the formation of calcium carbonate). The results established in this paper demonstrate that the addition of activated carbon in the cement paste, because of its very high BET surface area (close to 800 m2.g-1) and its specific reactivity with NO2, can significantly improve and prolong the de-polluting effect in presence of CO2 and even after complete carbonation of the surface of the cement paste.

  13. Preparation of lignin-based carbon aerogels as biomaterials for nano-supercapacitor

    NASA Astrophysics Data System (ADS)

    Yang, Bong Suk; Kang, Kyu-Young; Jeong, Myung-Joon

    2017-10-01

    Kraft and organosolv lignins, generally produced in chemical pulping and bio-refinery processes of lignocellulosic biomass, were used to prepare lignin-based carbon aerogels for supercapacitors as raw materials. The difference between lignins and lignin-based aerogels were compared by analyzing physical and chemical properties, including molecular weight, polydispersity, and reactivity with formaldehyde. Also, density, shrinkage, Brunauer-Emmett-Teller (BET) surface area and scanning electron microscope (SEM) images of the lignin-based aerogel were investigated. Kraft lignin consisting of coniferyl alcohol (G) and p-coumaryl alcohol (H) increased the reactivity of formaldehyde, formed a hydrogel well (porosity > 0.45), and specific surface area higher than organosolv lignin. In the case of kraft lignin, there were irregular changes such as oxidation and condensation in the pulping process. However, reaction sites with aromatic rings in lignin impacted the production of aerogel and required a long gelation period. The molecular weight of lignin influences the gelation time in producing lignin-based aerogel, and lignin composition affects the BET surface area and pore structures of the lignin-based carbon aerogels.

  14. Response Surface Modeling Tolerance and Inference Error Risk Specifications: Proposed Industry Standards

    NASA Technical Reports Server (NTRS)

    DeLoach, Richard

    2012-01-01

    This paper reviews the derivation of an equation for scaling response surface modeling experiments. The equation represents the smallest number of data points required to fit a linear regression polynomial so as to achieve certain specified model adequacy criteria. Specific criteria are proposed which simplify an otherwise rather complex equation, generating a practical rule of thumb for the minimum volume of data required to adequately fit a polynomial with a specified number of terms in the model. This equation and the simplified rule of thumb it produces can be applied to minimize the cost of wind tunnel testing.

  15. Effect of specific surface microstructures on substrate endothelialisation and thrombogenicity: Importance for stent design.

    PubMed

    Lutter, Christoph; Nothhaft, Matthias; Rzany, Alexander; Garlichs, Christoph D; Cicha, Iwona

    2015-01-01

    In coronary artery disease, highly stenosed arteries are frequently treated by stent implantation, which thereafter necessitates a dual-antiplatelet therapy (DAPT) in order to prevent stent-thrombosis. We hypothesized that specific patterns of microstructures on stents can accelerate endothelialisation thereby reducing their thrombogenicity and the DAPT duration. Differently designed, 2-5 μm high elevations or hollows were lithographically etched on silicon plates, subsequently coated with silicon carbide. Smooth silicon plates and bare metal substrates were used as controls. To assess attachment and growth of human umbilical vein endothelial cells under static or flow conditions, actin cytoskeleton was visualised with green phalloidin. Endothelial migration was assessed in a modified barrier assay. To investigate surface thrombogenicity, platelets were incubated on the structured surfaces in static and flow conditions, and visualised with fluorescein-conjugated P-selectin antibody. Images were taken with incident-light fluorescent microscope for non-transparent objects. Compared to smooth surface, flat cubic elevations (5 μm edge length) improved endothelial cell attachment and growth under static and dynamic conditions, whereas smaller, spiky structures (2 μm edge length) had a negative influence on endothelialisation. Endothelial cell migration was fastest on flat cubic elevations, hollows, and smooth surfaces, whereas spiky structures and bare metal had a negative effect on endothelial migration. Thrombogenicity assays under static and flow conditions showed that platelet adhesion was reduced on the flat elevations and the smooth surface, as compared to the spiky structures, the hollow design and the bare metal substrates. Surface microstructures strongly influence endothelialisation of substrates. Designing stents with surface topography which accelerates endothelialisation and reduces thrombogenicity may be of clinical benefit by improving the safety

  16. The Effect of Specific Surface Area of Chitin-Metal Silicate Coprocessed Excipient on the Chemical Decomposition of Cefotaxime Sodium.

    PubMed

    Al-Nimry, Suhair S; Alkhamis, Khouloud A; Alzarieni, Kawthar Z

    2017-02-01

    Chitin-metal silicates are multifunctional excipients used in tablets. Previously, a correlation between the surface acidity of chitin-calcium and chitin-magnesium silicate and the chemical decomposition of cefotaxime sodium was found but not with chitin-aluminum silicate. This lack of correlation could be due to the catalytic effect of silica alumina or the difference in surface area of the excipients. The objective of this study was to investigate the effect of the specific surface area of the excipient on the chemical decomposition of cefotaxime sodium in the solid state. Chitin was purified and coprocessed with different metal silicates to prepare the excipients. The specific surface area was determined using gas adsorption. The chemical decomposition was studied at constant temperature and relative humidity. Also, the degradation in solution was studied. A correlation was found between the degradation rate constant and the surface area of chitin-aluminum and chitin-calcium silicate but not with chitin-magnesium silicate. This was due to the small average pore diameter of this excipient. Also, the degradation in solution was slower than in solid state. In conclusion, the stability of cefotaxime sodium was dependent on the surface area of the excipient in contact with the drug. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  17. Top-down and bottom-up characterization of nitrated birch pollen allergen Bet v 1a with CZE hyphenated to an Orbitrap mass spectrometer.

    PubMed

    Gusenkov, Sergey; Stutz, Hanno

    2018-02-01

    Tyrosine (Tyr) residues of the major pollen allergen of birch Betula verrucosa, Bet v 1a, were nitrated by peroxynitrite. This modification enhances the allergenicity. Modified tyrosines were identified by analyzing intact allergen variants in combination with top-down and bottom-up approaches. Therefore, a laboratory-built sheath-liquid assisted ESI interface was applied for hyphenation of CE to an Orbitrap mass spectrometer to localize individual nitration sites. The major focus was on identification of primary nitration sites. The top-down approach unambiguously identified Tyr 5 as the most prominent modification site. Fragments from the allergen core and the C-terminal part carried up to three potential nitration sites, respectively. Thus, a bottom-up approach with tryptic digest was used as a complementary strategy which allowed for the unambiguous localization of nitration sites within the respective peptides. Nitration propensity for individual Tyr residues was addressed by comparison of MS signals of nitrated peptides relative to all cognates of homolog primary sequence. Combined data identified surface exposed Tyr 5 and Tyr 66 as major nitration sites followed by less accessible Tyr 158 whereas Tyr 81, 83 and 150 possess a lower nitration tendency and are apparently modified in variants with higher nitration levels. © 2018 The Authors. Electrophoresis published by Wiley-VCH Verlag GmbH & Co. KGaA.

  18. Graphene-Like 2D Porous Carbon Nanosheets Derived from Cornstalk Pith for Energy Storage Materials

    NASA Astrophysics Data System (ADS)

    Gao, Kezheng; Niu, Qingyuan; Tang, Qiheng; Guo, Yaqing; Wang, Lizhen

    2018-01-01

    Biomass materials from different organisms or different parts (even different periods) of the same organism have different microscopic morphologies, hierarchical pore structures and even elemental compositions. Therefore, carbon materials inheriting the unique hierarchical microstructure of different biomass materials may exhibit significantly different electrochemical properties. Cornstalk pith and cornstalk skin (dried by freeze-drying) exhibit significantly different microstructures due to their different biological functions. The cornstalk skin-based carbon (S-carbon) exhibits a thick planar morphology, and the Barrett-Emmett-Teller (BET) surface area is only about 332.07 m2 g-1. However, cornstalk pith-based carbon (P-carbon) exhibits a graphene-like 2D porous nanosheet structure with a rough, wrinkled morphology, and the BET surface area is about 805.17 m2 g-1. In addition, a P-carbon supercapacitor exhibits much higher specific capacitance and much better rate capability than an S-carbon supercapacitor in 6 M potassium hydroxide (KOH) electrolyte.

  19. Resolution dependence of petrophysical parameters derived from X-ray tomography of chalk

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Müter, D.; Sørensen, H. O.; Jha, D.

    2014-07-28

    X-ray computed tomography data from chalk drill cuttings were taken over a series of voxel dimensions, ranging from 320 to 25 nm. From these data sets, standard petrophysical parameters (porosity, surface area, and permeability) were derived and we examined the effect of the voxel dimension (i.e., image resolution) on these properties. We found that for the higher voxel dimensions, they are severely over or underestimated, whereas for 50 and 25 nm voxel dimension, the resulting values (5%–30% porosity, 0.2–2 m{sup 2}/g specific surface area, and 0.06–0.34 mD permeability) are within the expected range for this type of rock. We compared our resultsmore » to macroscopic measurements and in the case of surface area, also to measurements using the Brunauer-Emmett-Teller (BET) method and found that independent of the degree of compaction, the results from tomography amount to about 30% of the BET method. Finally, we concluded that at 25 nm voxel dimension, the essential features of the nanoscopic pore network in chalk are captured but better resolution is still needed to derive surface area.« less

  20. Synthesis of graphene aerogel for adsorption of bisphenol A

    NASA Astrophysics Data System (ADS)

    Trinh, Truong Thi Phuong Nguyet Xuan; Long, Nguyen Huynh Bach Son; Quang, Dong Thanh; Hieu, Nguyen Huu

    2018-04-01

    In this research, graphene aerogel (GA) was synthesized by chemical reduction method using ethylene diamine as a reducing agent. The morphology and properties of GA were characterized by calculating apparent density, Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, and Brunauer-Emmett-Teller (BET) specific surface area. High-performance liquid chromatography (HPLC) was used to quantify the amount of the residual bisphenol A (BPA) concentration. The analysis results showed that GA exhibited low density ranging from 4-8 mg/cm3, hydrophobicity, high porosity, and specific surface area of 1883 m2/g according to BET. The obtained GA was used as an adsorbent for BPA. The effects of pH, contact time, and initial BPA concentration on the adsorption were investigated. The adsorption equilibrium time could be reached within 240 minutes. The adsorption data were well-fitted to pseudo-second-order kinetic equation and Langmuir isotherm model. The maximum adsorption capacity of GA for BPA calculated by the Langmuir model was 185.185 mg/g at pH 7. Accordingly, GA could be considered as promising adsorbents for BPA in water.

  1. Real-time specific surface area measurements via laser-induced breakdown spectroscopy

    USGS Publications Warehouse

    Washburn, Kathryn E.; Birdwell, Justin E.; Howard, James E.

    2017-01-01

    From healthcare to cosmetics to environmental science, the specific surface area (SSA) of micro- and mesoporous materials or products can greatly affect their chemical and physical properties. SSA results are also widely used to examine source rocks in conventional and unconventional petroleum resource plays. Despite its importance, current methods to measure SSA are often cumbersome, time-consuming, or require cryogenic consumables (e.g., liquid nitrogen). These methods are not amenable to high-throughput environments, have stringent sample preparation requirements, and are not practical for use in the field. We present a new application of laser-induced breakdown spectroscopy for rapid measurement of SSA. This study evaluates geological samples, specifically organic-rich oil shales, but the approach is expected to be applicable to many other types of materials. The method uses optical emission spectroscopy to examine laser-generated plasma and quantify the amount of argon adsorbed to a sample during an inert gas purge. The technique can accommodate a wide range of sample sizes and geometries and has the potential for field use. These advantages for SSA measurement combined with the simultaneous acquisition of composition information make this a promising new approach for characterizing geologic samples and other materials.

  2. Synthesis of zinc aluminate with high surface area by microwave hydrothermal method applied in the transesterification of soybean oil (biodiesel)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quirino, M.R.; Oliveira, M.J.C.; Keyson, D.

    Highlights: • ZnAl{sub 2}O{sub 4} spinel was synthesized by the microwave hydrothermal method in only 15 or 30 min. • The powders show high specific surface area. • ZAT{sub b}15 showed activity of 52.22% for the conversion of soybean oil into biodiesel. - Abstract: Zinc aluminate is a material with high thermal stability and high mechanical strength that, owing to these properties, is used as a catalyst or support. In this work, zinc aluminate spinel was synthesized by the microwave hydrothermal method in only 15 or 30 min at a low temperature (150 °C) without templates, using only Al(NO{sub 3}){submore » 3}·9H{sub 2}O, Zn(NO{sub 3}){sub 2}·6H{sub 2}O, and urea as precursors and applied in the transesterification of soybean oil. X-ray diffraction analysis showed that ZnAl{sub 2}O{sub 4} had a cubic structure without secondary phases. The nitrogen adsorption measurements (BET) revealed a high surface area (266.57 m{sup 2} g{sup −1}) for the nanopowder synthesized in 15 min. This powder showed activity of 52.22% for the catalytic conversion of soybean oil into biodiesel by transesterification.« less

  3. Preparation of High Surface Area Activated Carbon from Spent Phenolic Resin by Microwave Heating and KOH Activation

    NASA Astrophysics Data System (ADS)

    Cheng, Song; Zhang, Libo; Zhang, Shengzhou; Xia, Hongying; Peng, Jinhui

    2018-01-01

    The spent phenolic resin is as raw material for preparing high surface area activated carbon (HSAAC) by microwave-assisted KOH activation. The effects of microwave power, activation duration and impregnation ratio (IR) on the iodine adsorption capability and yield of HSAAC were investigated. The surface characteristics of HSAAC were characterized by nitrogen adsorption isotherms, FTIR, SEM and TEM. The operating variables were optimized utilizing the response surface methodology (RSM) and were identified to be microwave power of 700 W, activation duration of 15 min and IR of 4, corresponding to a yield of 51.25 % and an iodine number of 2,384 mg/g. The pore structure parameters of the HSAAC, i. e., Brunauer-Emmett-Teller (BET) surface area, total pore volume, and average pore diameter were estimated to be 4,269 m2/g, 2.396 ml/g and 2.25 nm, respectively, under optimum conditions. The findings strongly support the feasibility of microwave-assisted KOH activation for preparation of HSAAC from spent phenolic resin.

  4. Optimization of mesoporous carbons for efficient adsorption of berberine hydrochloride from aqueous solutions.

    PubMed

    Li, Yin; Fu, Jie; Deng, Shuguang; Lu, Xiuyang

    2014-06-15

    Sixteen mesoporous carbon adsorbents were synthesized by varying the ratio of soft to hard templates in order to optimize the pore textural properties of these adsorbents. The mesoporous carbon adsorbents have a high BET specific surface area (1590.3-2193.5 m(2)/g), large pore volume (1.72-2.56 cm(3)/g), and uniform pore size distribution with a median pore diameter ranging from 3.51 nm to 4.52 nm. It was observed that pore textural properties of the carbon adsorbents critically depend on the molar ratio of carbon sources to templates, and the hard template plays a more important role than the soft template in manipulating the pore textures. Adsorption isotherms of berberine hydrochloride at 303 K were measured to evaluate the adsorption efficacy of these adsorbents. The adsorption of berberine hydrochloride from aqueous solutions on the sixteen mesoporous carbon adsorbents synthesized in this work is very efficient, and the adsorption equilibrium capacities on all samples are more than double the adsorption capacities of berberine hydrochloride of the benchmark adsorbents (polymer resins and spherical activated carbons) at similar conditions. It was observed from the adsorption experiments that the equilibrium adsorption amounts of berberine hydrochloride are strongly correlated with the BET specific surface area and pore volume of the adsorbents. The adsorbent with the highest BET of 2193.5 m(2)/g displayed the largest adsorption capacity of 574 mg/g at an equilibrium concentration of 0.10mg/mL of berberine hydrochloride in an aqueous solution. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Nanoscale Fe/Ag particles activated persulfate: optimization using response surface methodology.

    PubMed

    Silveira, Jefferson E; Barreto-Rodrigues, Marcio; Cardoso, Tais O; Pliego, Gema; Munoz, Macarena; Zazo, Juan A; Casas, José A

    2017-05-01

    This work studied the bimetallic nanoparticles Fe-Ag (nZVI-Ag) activated persulfate (PS) in aqueous solution using response surface methodology. The Box-Behnken design (BBD) was employed to optimize three parameters (nZVI-Ag dose, reaction temperature, and PS concentration) using 4-chlorophenol (4-CP) as the target pollutant. The synthesis of nZVI-Ag particles was carried out through a reduction of FeCl 2 with NaBH 4 followed by reductive deposition of Ag. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area. The BBD was considered a satisfactory model to optimize the process. Confirmatory tests were carried out using predicted and experimental values under the optimal conditions (50 mg L -1 nZVI-Ag, 21 mM PS at 57 °C) and the complete removal of 4-CP achieved experimentally was successfully predicted by the model, whereas the mineralization degree predicted (90%) was slightly overestimated against the measured data (83%).

  6. Not my "type": larval dispersal dimorphisms and bet-hedging in opisthobranch life histories.

    PubMed

    Krug, Patrick J

    2009-06-01

    When conditions fluctuate unpredictably, selection may favor bet-hedging strategies that vary offspring characteristics to avoid reproductive wipe-outs in bad seasons. For many marine gastropods, the dispersal potential of offspring reflects both maternal effects (egg size, egg mass properties) and larval traits (development rate, habitat choice). I present data for eight sea slugs in the genus Elysia (Opisthobranchia: Sacoglossa), highlighting potentially adaptive variation in traits like offspring size, timing of metamorphosis, hatching behavior, and settlement response. Elysia zuleicae produced both planktotrophic and lecithotrophic larvae, a true case of poecilogony. Both intracapsular and post-hatching metamorphosis occurred among clutches of "Boselia" marcusi, E. cornigera, and E. crispata, a dispersal dimorphism often misinterpreted as poecilogony. Egg masses of E. tuca hatched for up to 16 days but larvae settled only on the adult host alga Halimeda, whereas most larvae of E. papillosa spontaneously metamorphosed 5-7 days after hatching. Investment in extra-capsular yolk may allow mothers to increase larval size relative to egg size and vary offspring size within and among clutches. Flexible strategies of larval dispersal and offspring provisioning in Elysia spp. may represent adaptations to the patchy habitat of these specialized herbivores, highlighting the evolutionary importance of variation in a range of life-history traits.

  7. Surface display of metal binding domain derived from PbrR on Escherichia coli specifically increases lead(II) adsorption.

    PubMed

    Hui, Chang-Ye; Guo, Yan; Yang, Xue-Qin; Zhang, Wen; Huang, Xian-Qing

    2018-05-01

    To improve the Pb 2+ biosorption capacity of the potential E. coli biosorbent, a putative Pb 2+ binding domain (PbBD) derived from PbrR was efficiently displayed on to the E. coli cell surface. The PbBD was obtained by truncating the N-terminal DNA-binding domain and C-terminal redundant amino acid residues of the Pb 2+ -sensing transcriptional factor PbrR. Whole-cell sorbents were constructed with the full-length PbrR and PbBD of PbrR genetically engineered onto the surface of E. coli cells using Lpp-OmpA as the anchor. Followed by a 1.71-fold higher display of PbBD than PbrR, the presence of PbBD on the surface of E. coli cells enabled a 1.92-fold higher Pb 2+ biosorption than that found in PbrR-displayed cells. Specific Pb 2+ binding via PbBD was the same as Pb 2+ binding via the full-length PbrR, with no observable decline even in the presence of Zn 2+ and Cd 2+ . Since surface-engineered E. coli cells with PbBD increased the Pb 2+ binding capacity and did not affect the adsorption selectivity, this suggests that surface display of the metal binding domain derived from MerR-like proteins may be used for the bioremediation of specific toxic heavy metals.

  8. Drop drying on surfaces determines chemical reactivity - the specific case of immobilization of oligonucleotides on microarrays

    PubMed Central

    2013-01-01

    Background Drop drying is a key factor in a wide range of technical applications, including spotted microarrays. The applied nL liquid volume provides specific reaction conditions for the immobilization of probe molecules to a chemically modified surface. Results We investigated the influence of nL and μL liquid drop volumes on the process of probe immobilization and compare the results obtained to the situation in liquid solution. In our data, we observe a strong relationship between drop drying effects on immobilization and surface chemistry. In this work, we present results on the immobilization of dye labeled 20mer oligonucleotides with and without an activating 5′-aminoheptyl linker onto a 2D epoxysilane and a 3D NHS activated hydrogel surface. Conclusions Our experiments identified two basic processes determining immobilization. First, the rate of drop drying that depends on the drop volume and the ambient relative humidity. Oligonucleotides in a dried spot react unspecifically with the surface and long reaction times are needed. 3D hydrogel surfaces allow for immobilization in a liquid environment under diffusive conditions. Here, oligonucleotide immobilization is much faster and a specific reaction with the reactive linker group is observed. Second, the effect of increasing probe concentration as a result of drop drying. On a 3D hydrogel, the increasing concentration of probe molecules in nL spotting volumes accelerates immobilization dramatically. In case of μL volumes, immobilization depends on whether the drop is allowed to dry completely. At non-drying conditions, very limited immobilization is observed due to the low oligonucleotide concentration used in microarray spotting solutions. The results of our study provide a general guideline for microarray assay development. They allow for the initial definition and further optimization of reaction conditions for the immobilization of oligonucleotides and other probe molecule classes to different

  9. Surface plasmon-enhanced fluorescence on Au nanohole array for prostate-specific antigen detection

    PubMed Central

    Zhang, Qingwen; Wu, Lin; Wong, Ten It; Zhang, Jinling; Liu, Xiaohu; Zhou, Xiaodong; Bai, Ping; Liedberg, Bo; Wang, Yi

    2017-01-01

    Localized surface plasmon (LSP) has been widely applied for the enhancement of fluorescence emission for biosensing owing to its potential for strong field enhancement. However, due to its small penetration depth, LSP offers limited fluorescence enhancement over a whole sensor chip and, therefore, insufficient sensitivity for the detection of biomolecules, especially large molecules. We demonstrate the simultaneous excitation of LSP and propagating surface plasmon (PSP) on an Au nanohole array under Kretschmann configuration for the detection of prostate-specific antigen with a sandwich immunoassay. The proposed method combines the advantages of high field enhancement by LSP and large surface area probed by PSP field. The simulated results indicated that a maximum enhancement of electric field intensity up to 1,600 times can be achieved under the simultaneous excitation of LSP and PSP modes. The sandwich assay of PSA carried out on gold nanohole array substrate showed a limit of detection of 140 fM supporting coexcitation of LSP and PSP modes. The limit of detection was approximately sevenfold lower than that when only LSP was resonantly excited on the same substrate. The results of this study demonstrate high fluorescence enhancement through the coexcitation of LSP and PSP modes and pave a way for its implementation as a highly sensitive bioassay. PMID:28392689

  10. Specific capture and detection of Staphylococcus aureus with high-affinity modified aptamers to cell surface components

    PubMed Central

    Baumstummler, A; Lehmann, D; Janjic, N; Ochsner, UA

    2014-01-01

    Slow off-rate modified aptamer (SOMAmer) reagents were generated to several Staphylococcus aureus cell surface-associated proteins via SELEX with multiple modified DNA libraries using purified recombinant or native proteins. High-affinity binding agents with sub-nanomolar Kd's were obtained for staphylococcal protein A (SpA), clumping factors (ClfA, ClfB), fibronectin-binding proteins (FnbA, FnbB) and iron-regulated surface determinants (Isd). Further screening revealed several SOMAmers that specifically bound to Staph. aureus cells from all strains that were tested, but not to other staphylococci or other bacteria. SpA and ClfA SOMAmers proved useful for the selective capture and enrichment of Staph. aureus cells, as shown by culture and PCR, leading to improved limits of detection and efficient removal of PCR inhibitors. Detection of Staph. aureus cells was enhanced by several orders of magnitude when the bacterial cell surface was coated with SOMAmers followed by qPCR of the SOMAmers. Furthermore, fluorescence-labelled SpA SOMAmers demonstrated their utility as direct detection agents in flow cytometry. Significance and Impact of the Study Monitoring for microbial contamination of food, water, nonsterile products or the environment is typically based on culture, PCR or antibodies. Aptamers that bind with high specificity and affinity to well-conserved cell surface epitopes represent a promising novel type of reagents to detect bacterial cells without the need for culture or cell lysis, including for the capture and enrichment of bacteria present at low cell densities and for the direct detection via qPCR or fluorescent staining. PMID:24935714

  11. Porphyromonas gingivalis Uses Specific Domain Rearrangements and Allelic Exchange to Generate Diversity in Surface Virulence Factors.

    PubMed

    Dashper, Stuart G; Mitchell, Helen L; Seers, Christine A; Gladman, Simon L; Seemann, Torsten; Bulach, Dieter M; Chandry, P Scott; Cross, Keith J; Cleal, Steven M; Reynolds, Eric C

    2017-01-01

    Porphyromonas gingivalis is a keystone pathogen of chronic periodontitis. The virulence of P. gingivalis is reported to be strain related and there are currently a number of strain typing schemes based on variation in capsular polysaccharide, the major and minor fimbriae and adhesin domains of Lys-gingipain (Kgp), amongst other surface proteins. P. gingivalis can exchange chromosomal DNA between strains by natural competence and conjugation. The aim of this study was to determine the genetic variability of P. gingivalis strains sourced from international locations over a 25-year period and to determine if variability in surface virulence factors has a phylogenetic basis. Whole genome sequencing was performed on 13 strains and comparison made to 10 previously sequenced strains. A single nucleotide polymorphism-based phylogenetic analysis demonstrated a shallow tri-lobed phylogeny. There was a high level of reticulation in the phylogenetic network, demonstrating extensive horizontal gene transfer between the strains. Two highly conserved variants of the catalytic domain of the major virulence factor the Kgp proteinase (Kgp cat I and Kgp cat II) were found. There were three variants of the fourth Kgp C-terminal cleaved adhesin domain. Specific variants of the cell surface proteins FimA, FimCDE, MfaI, RagAB, Tpr, and PrtT were also identified. The occurrence of all these variants in the P. gingivalis strains formed a mosaic that was not related to the SNP-based phylogeny. In conclusion P. gingivalis uses domain rearrangements and genetic exchange to generate diversity in specific surface virulence factors.

  12. In the Casino of Life: Betting on Risks and Ignoring the Consequences of Climate Change and Hazards

    NASA Astrophysics Data System (ADS)

    Brosnan, D. M.

    2016-12-01

    Even faced with strong scientific evidence decision-makers cite uncertainty and delay actions. Scientists, confident in the quality of their science and acknowledging that uncertainty while present is low by scientific standards, become more frustrated as their information is ignored. Decreasing scientific uncertainty, a hallmark of long term studies e.g. IPCC reports does little to motivate decision-makers. Imperviousness to scientific data is prevalent across all scales. Municipalities prefer to spend millions of dollars on engineered solutions to climate change and hazards, even if science shows that they perform less well than nature-based ones and cost much more. California is known to be at risk from tsunamis generated by earthquakes off Alaska. A study using a 9.1 earthquake, similar to a 1965 event, calculated the immediate economic price tag in infrastructure loss and business interruption at 9.5billion. The exposure of Los Angeles/Long Beach port trade to damage and downtime exceeds 1.2billion; business interruption would triple the figure. Yet despite several excellent scientific studies, the State is ill prepared; investments in infrastructure commerce and conservation risk being literally washed away. Globally there is a 5-10% probability of an extreme geohazard, e.g, a Tambora like eruption, occurring in this century. With a "value of statistical life" of 2.2 million and population at 7 billion the risk for fatalities alone is 1.1-7billion per yr. But there is little interest in investing the $0.5-3.5 billion per year in volcano monitoring necessary to reduce fatalities and lower risks of global conflict, starvation, and societal destruction. More science and less uncertainty is clearly not the driver of action. But is speaking with certainty really the answer? Decision makers and scientists are in the same casino of life but rarely play at the same tables. Decision makers bet differently to scientists. To motivate action we need to be cognizant of

  13. A functionalized poly(ethylene glycol)-based bioassay surface chemistry that facilitates bio-immobilization and inhibits non-specific protein, bacterial, and mammalian cell adhesion

    PubMed Central

    Harbers, Gregory M.; Emoto, Kazunori; Greef, Charles; Metzger, Steven W.; Woodward, Heather N.; Mascali, James J.; Grainger, David W.; Lochhead, Michael J.

    2008-01-01

    This paper describes a new bioassay surface chemistry that effectively inhibits non-specific biomolecular and cell binding interactions, while providing a capacity for specific immobilization of desired biomolecules. Poly(ethylene glycol) (PEG) as the primary component in nonfouling film chemistry is well-established, but the multicomponent formulation described here is unique in that it (1) is applied in a single, reproducible, solution-based coating step; (2) can be applied to diverse substrate materials without the use of special primers; and (3) is readily functionalized to provide specific attachment chemistries. Surface analysis data are presented, detailing surface roughness, polymer film thickness, and film chemistry. Protein non-specific binding assays demonstrate significant inhibition of serum, fibrinogen, and lysozyme adsorption to coated glass, indium tin oxide, and tissue culture polystyrene dishes. Inhibition of S. aureus and K. pneumoniae microbial adhesion in a microfluidic flow cell, and inhibition of fibroblast cell adhesion from serum-based cell culture is shown. Effective functionalization of the coating is demonstrated by directing fibroblast adhesion to polymer surfaces activated with an RGD peptide. Batch-to-batch reproducibility data are included. The in situ cross-linked PEG-based coating chemistry is unique in its formulation, and its surface properties are attractive for a broad range of in vitro bioassay applications. PMID:18815622

  14. Cell-mediated immunity to herpes simplex virus: recognition of type-specific and type-common surface antigens by cytotoxic T cell populations.

    PubMed Central

    Eberle, R; Russell, R G; Rouse, B T

    1981-01-01

    In this communication, we examine the specificity of anti-herpes simplex virus (HSV) cytotoxic T lymphocytes (CTL). Serological studies of the two related HSV serotypes (HSV-1 and HSV-2) have revealed both type-specific and cross-reactive antigenic determinants in the viral envelope and on the surface of infected cells. By analysis of cytotoxicity of CTL, generated in vitro by restimulation of splenocytes from mice primed with one or the other HSV serotype, the recognition of both type-specific and cross-reactive determinants on infected target cells by anti-HSV CTL was detectable. Thus, effector cells generated by priming and restimulating with the same virus recognized both type-specific and cross-reactive determinants on target cells infected with the homologous virus, but only cross-reactive determinants on target cells infected with the heterologous HSV serotype. CTL generated by restimulation with the heterologous virus were capable of recognizing only the cross-reactive determinants on either HSV-1- or HSV-2-infected target cells. These results indicate that two subpopulations of CTL exist in a population of anti-HSV immune spleen cells--those which recognize type-specific determinants and those specific for cross-reactive antigenic determinants present on the surface of HSV infected cells. The type-specific subset of anti-HSV CTL was shown to recognize the gC glycoprotein of HSV-1 infected target cells. In addition to the gC glycoprotein, at least one other type-specific surface antigen was also recognized by anti-HSV CTL in addition to the cross-reactive determinants recognized by anti-HSV CTL. PMID:6277790

  15. "Click" on Alkynylated Carbon Quantum Dots: An Efficient Surface Functionalization for Specific Biosensing and Bioimaging.

    PubMed

    Gao, Ming Xuan; Yang, Lin; Zheng, Yi; Yang, Xiao Xi; Zou, Hong Yan; Han, Jing; Liu, Ze Xi; Li, Yuan Fang; Huang, Cheng Zhi

    2017-02-10

    Surface functionalization is an essential pre requisite for wide and specific applications of nanoparticles such as photoluminescent (PL) carbon quantum dots (CQDs), but it remains a major challenge. In this report, alkynylated CQDs, prepared from carboxyl-rich CQDs through amidation with propargylamine in the presence of 1,1'-carbonyldiimidazole, were modified efficiently with azido molecular beacon DNA through a copper(I)-catalyzed alkyne-azide cycloaddition reaction (CuAAC). As a proof-of-concept, the DNA-modified CQDs are then bonded with gold nanoparticles (AuNPs, 5 nm) through a gold-sulfur bond. Owing to the emission enhancement, this complex can then be applied to the recognition of a single-base- mismatched target. The same functionalizing strategy applied to click the alkynylated CQDs with a nuclear localization sequence (NLS) peptide showed that the NLS-modified CQDs could target the nuclei specifically. These results indicate that surface functionalization of CQDs through a nonstoichiometric copper chalcogenide nanocrystal- (nsCuCNC-) catalyzed click reaction is efficient, and has significant potential in the fields of biosensing and bioimaging. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Analysis of the surfaces of wood tissues and pulp fibers using carbohydrate-binding modules specific for crystalline cellulose and mannan.

    PubMed

    Filonova, Lada; Kallas, Asa M; Greffe, Lionel; Johansson, Gunnar; Teeri, Tuula T; Daniel, Geoffrey

    2007-01-01

    Carbohydrate binding modules (CBMs) are noncatalytic substrate binding domains of many enzymes involved in carbohydrate metabolism. Here we used fluorescent labeled recombinant CBMs specific for crystalline cellulose (CBM1(HjCel7A)) and mannans (CBM27(TmMan5) and CBM35(CjMan5C)) to analyze the complex surfaces of wood tissues and pulp fibers. The crystalline cellulose CBM1(HjCel7A) was found as a reliable marker of both bacterially produced and plant G-layer cellulose, and labeling of spruce pulp fibers with CBM1(HjCel7A) revealed a signal that increased with degree of fiber damage. The mannan-specific CBM27(TmMan5) and CBM35(CjMan5C) CBMs were found to be more specific reagents than a monoclonal antibody specific for (1-->4)-beta-mannan/galacto-(1-->4)-beta-mannan for mapping carbohydrates on native substrates. We have developed a quantitative fluorometric method for analysis of crystalline cellulose accumulation on fiber surfaces and shown a quantitative difference in crystalline cellulose binding sites in differently processed pulp fibers. Our results indicated that CBMs provide useful, novel tools for monitoring changes in carbohydrate content of nonuniform substrate surfaces, for example, during wood or pulping processes and possibly fiber biosynthesis.

  17. Potentiometric surface and specific conductance of the Sparta and Memphis aquifers in eastern Arkansas, 1995

    USGS Publications Warehouse

    Stanton, Gregory P.

    1997-01-01

    The Sparta and Memphis aquifers in eastern and south-central Arkansas are a major source of water for industrial, public supply, and agricultural uses. An estimated 240 million gallons per day was withdrawn from the Sparta and Memphis aquifers in 1995, an increase of about 17 million gallons per day from 1990. During the spring and early summer of 1995, the water level in the Sparta and Memphis aquifers was measured in 145 wells, the specific conductance of 101 ground-water samples collected from those aquifers was measured. Maps of areal distribution of potentiometric surface and specific conductance generated from these data reveal spatial trends in these parameters across the eastern and south-central Arkansas study area. The altitude of the potentiometric surface ranged from about 206 feet below sea level in Union County to about 307 feet above sea level in Saline County. The potentiometric surface of the Sparta and Memphis aquifers contains cones of depression descending below sea level in the central and southern portions of the study area, and a potentiometric high along the western study area boundary. Major recharge areas exhibit potentiometric highs greater than 200 feet above sea level and specific conductance values less than 200 microsiemens per centimeter, and generally are located in the outcrop/subcrop areas on the southern one-third of the western boundary and the northern portion of the study area. The regional direction of ground-water flow is from the north and west to the south and east, away from the outcrop and subcrop and northern regions, except near areas affected by intense ground-water withdrawals; such areas are manifested by large cones of depression centered in Columbia, Jefferson, and Union Counties. The cones of depression in adjoining Columbia and Union Counties are coalescing at or near sea level. The lowest water level measured was about 206 feet below sea level in Union County. Increased specific conductance values were measured

  18. Sulfur-doped nanoporous carbon spheres with ultrahigh specific surface area and high electrochemical activity for supercapacitor

    NASA Astrophysics Data System (ADS)

    Liu, Simin; Cai, Yijin; Zhao, Xiao; Liang, Yeru; Zheng, Mingtao; Hu, Hang; Dong, Hanwu; Jiang, Sanping; Liu, Yingliang; Xiao, Yong

    2017-08-01

    Development of facile and scalable synthesis process for the fabrication of nanoporous carbon materials with large specific surface areas, well-defined nanostructure, and high electrochemical activity is critical for the high performance energy storage applications. The key issue is the dedicated balance between the ultrahigh surface area and highly porous but interconnected nanostructure. Here, we demonstrate the fabrication of new sulfur doped nanoporous carbon sphere (S-NCS) with the ultrahigh surface area up to 3357 m2 g-1 via a high-temperature hydrothermal carbonization and subsequent KOH activation process. The as-prepared S-NCS which integrates the advantages of ultrahigh porous structure, well-defined nanospherical and modification of heteroatom displays excellent electrochemical performance. The best performance is obtained on S-NCS prepared by the hydrothermal carbonization of sublimed sulfur and glucose, S-NCS-4, reaching a high specific capacitance (405 F g-1 at a current density of 0.5 A g-1) and outstanding cycle stability. Moreover, the symmetric supercapacitor is assembled by S-NCS-4 displays a superior energy density of 53.5 Wh kg-1 at the power density of 74.2 W kg-1 in 1.0 M LiPF6 EC/DEC. The synthesis method is simple and scalable, providing a new route to prepare highly porous and heteroatom-doped nanoporous carbon spheres for high performance energy storage applications.

  19. New findings on the influence of carbon surface curvature on energetics of benzene adsorption from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Wiśniewski, Marek; Werengowska-Ciećwierz, Karolina; Terzyk, Artur P.

    2015-01-01

    Immersional measurements of benzene adsorption form dilute aqueous solutions are reported for the first time together with the measurements of the enthalpy of benzene adsorption. Benzene adsorption from aqueous solution is an exothermic process. Our results show that with the decrease in carbon nanotube diameter the process becomes more exothermic, and the enthalpy of benzene adsorption correlates with the BET surface area and the electrostatic field strength of the tubes. Possible explanations of the results are proposed, and the most probable is that the change in carbon hybridisation with curvature leads to creation of stronger energetically adsorption sites than observed for graphite.

  20. Specific capture and detection of Staphylococcus aureus with high-affinity modified aptamers to cell surface components.

    PubMed

    Baumstummler, A; Lehmann, D; Janjic, N; Ochsner, U A

    2014-10-01

    Slow off-rate modified aptamer (SOMAmer) reagents were generated to several Staphylococcus aureus cell surface-associated proteins via SELEX with multiple modified DNA libraries using purified recombinant or native proteins. High-affinity binding agents with sub-nanomolar Kd 's were obtained for staphylococcal protein A (SpA), clumping factors (ClfA, ClfB), fibronectin-binding proteins (FnbA, FnbB) and iron-regulated surface determinants (Isd). Further screening revealed several SOMAmers that specifically bound to Staph. aureus cells from all strains that were tested, but not to other staphylococci or other bacteria. SpA and ClfA SOMAmers proved useful for the selective capture and enrichment of Staph. aureus cells, as shown by culture and PCR, leading to improved limits of detection and efficient removal of PCR inhibitors. Detection of Staph. aureus cells was enhanced by several orders of magnitude when the bacterial cell surface was coated with SOMAmers followed by qPCR of the SOMAmers. Furthermore, fluorescence-labelled SpA SOMAmers demonstrated their utility as direct detection agents in flow cytometry. Significance and impact of the study: Monitoring for microbial contamination of food, water, nonsterile products or the environment is typically based on culture, PCR or antibodies. Aptamers that bind with high specificity and affinity to well-conserved cell surface epitopes represent a promising novel type of reagents to detect bacterial cells without the need for culture or cell lysis, including for the capture and enrichment of bacteria present at low cell densities and for the direct detection via qPCR or fluorescent staining. © 2014 Soma Logic, Inc. published by John Wiley & Sons Ltd On behalf of the society for Applied Microbiology.

  1. An interferometric study of the dissolution kinetics of anorthite: The role of reactive surface area

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luettge, A.; Bolton, E.W.; Lasaga, A.C.

    1999-07-01

    An optical interferometry system has been used to study the dynamics of the dissolution of anorthite (010) cleavage surfaces. With this technique, it is possible to measure directly the surface retreat of alumino-silicates as a function of time and thereby the dissolution rate using a new application of interferometry. The dissolution experiments are carried out in a flow-through cell system with a near endmember anorthite (An{sub 98}) from Miyake-Jima, Tokyo, Japan, Perchloric acid solutions (pH 3) were used at a constant temperature of 25 C. After having measured the topography of the original pristine anorthite surface, measurements of the surfacemore » normal retreat were taken after 48,84,120, and 168 hrs of run duration at 15 different regions on the surface. An internal-reference technique allows absolute measurements of the changes in surface height for the very first time. From these measurements, an average bulk rate for dissolution of the (010) anorthite surface is calculated to be 5.7 x 10{sup {minus}13} [moles/cm{sub 2}/sec]. Finally, their directly determined bulk rate for the (010) face is compared with the bulk rates calculated from the rate law obtained from powder experiments and using the BET or total surface area.« less

  2. Activated carbon with excellent chromium(VI) adsorption performance prepared by acid-base surface modification.

    PubMed

    Liu, S X; Chen, X; Chen, X Y; Liu, Z F; Wang, H L

    2007-03-06

    In the present work, activated carbon (AC) with excellent Cr(VI) adsorption performance especially at low concentrations was prepared by an acid-base surface modification method. Raw activated carbon (AC(0)) was first oxidized in boiling HNO(3) (AC(1)), then treated with a mixture of NaOH and NaCl (AC(2)). Batch equilibrium and continuous column adsorption were conducted to evaluate the adsorption performance. Boehm titration, elemental analysis, and N(2)/77K adsorption isotherm methods were used to characterize the surface properties and pore structure of modified ACs. The results revealed that the modified AC exhibited excellent Cr(VI) adsorption performance in terms of adsorption capacity and adsorption rate: AC(2)>AC(1)>AC(0). Modification caused S(BET) to decrease and the total number of surface oxygen acidic groups to increase. HNO(3) oxidization produced positive acid groups, and subsequently NaOH treatment replaced H(+) of surface acid groups by Na(+), and the acidity of AC decreased. The main cause of higher Cr(VI) adsorption capacity and rate for AC(2) was the presence of more oxygen surface acidic groups and suitable surface acidity. HNO(3)-NaOH modification shows potential for the preparation of high quality AC for the effective removal of low concentrations of Cr(VI).

  3. Ligand-specific regulation of the extracellular surface of a G-protein-coupled receptor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bokoch, Michael P.; Zou, Yaozhong; Rasmussen, Søren G.F.

    G-protein-coupled receptors (GPCRs) are seven-transmembrane proteins that mediate most cellular responses to hormones and neurotransmitters. They are the largest group of therapeutic targets for a broad spectrum of diseases. Recent crystal structures of GPCRs have revealed structural conservation extending from the orthosteric ligand-binding site in the transmembrane core to the cytoplasmic G-protein-coupling domains. In contrast, the extracellular surface (ECS) of GPCRs is remarkably diverse and is therefore an ideal target for the discovery of subtype-selective drugs. However, little is known about the functional role of the ECS in receptor activation, or about conformational coupling of this surface to the nativemore » ligand-binding pocket. Here we use NMR spectroscopy to investigate ligand-specific conformational changes around a central structural feature in the ECS of the {beta}{sub 2} adrenergic receptor: a salt bridge linking extracellular loops 2 and 3. Small-molecule drugs that bind within the transmembrane core and exhibit different efficacies towards G-protein activation (agonist, neutral antagonist and inverse agonist) also stabilize distinct conformations of the ECS. We thereby demonstrate conformational coupling between the ECS and the orthosteric binding site, showing that drugs targeting this diverse surface could function as allosteric modulators with high subtype selectivity. Moreover, these studies provide a new insight into the dynamic behaviour of GPCRs not addressable by static, inactive-state crystal structures.« less

  4. A note on specific variability of long surface gravity waves and drag coefficient in coastal upwelling zone

    NASA Astrophysics Data System (ADS)

    Krzyścin, Janusz

    1990-01-01

    In this paper we solve analytically wave kinematic equations and the wave energy transport equation, for basic long surface gravity wave in the coastal upwelling zone. Using Gent and Taylor's (1978) parameterization of drag coefficient (which includes interaction between long surface waves and the air flow) we find variability of this coefficient due to wave amplification and refraction caused by specific surface water current in the region. The drag coefficient grows towards the shore. The growth is faster for stronger current. When the angle between waves and the current is less than 90° the growth is mainly connected with the waves steepness, but when the angle is larger, it is caused by relative growth of the wave phase velocity.

  5. Dye adsorption onto activated carbons from tyre rubber waste using surface coverage analysis.

    PubMed

    Mui, Edward L K; Cheung, W H; Valix, Marjorie; McKay, Gordon

    2010-07-15

    Two types of activated carbons from tyre char (with or without sulphuric acid treatment) were produced via carbon dioxide activation with BET surface areas in the range 59-1118 m(2)/g. Other characterisation tests include micropore and mesopore surface areas and volumes, pH, and elemental compositions, particularly heteroatoms such as nitrogen and sulphur. They were correlated to the adsorption capacity which were in the range of 0.45-0.71 mmol/g (untreated) and 0.62-0.84 mmol/g (acid-treated) for Acid Blue 25. In the case of larger-sized molecules like Acid Yellow 117, capacities were in the range of 0.23-0.42 mmol/g (untreated) and 0.29-0.40 mmol/g (acid-treated). Some tyre carbons exhibit a more superior performance than a microporous, commercial activated carbon (Calgon F400). By modelling the dye adsorption equilibrium data, the Redlich-Peterson isotherm is adopted as it has the lowest SSE. Based on the surface coverage analysis, a novel molecular orientation modelling of adsorbed dyes has been proposed and correlated with surface area and surface charge. For the acid dyes used in this study, molecules were likely to be adsorbed by the mesopore areas. Copyright 2010 Elsevier Inc. All rights reserved.

  6. SU-E-T-04: 3D Printed Patient-Specific Surface Mould Applicators for Brachytherapy Treatment of Superficial Lesions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cumming, I; Lasso, A; Rankin, A

    2014-06-01

    Purpose: Evaluate the feasibility of constructing 3D-printed patient-specific surface mould applicators for HDR brachytherapy treatment of superficial lesions. Methods: We propose using computer-aided design software to create 3D printed surface mould applicators for brachytherapy. A mould generation module was developed in the open-source 3D Slicer ( http://www.slicer.org ) medical image analysis platform. The system extracts the skin surface from CT images, and generates smooth catheter paths over the region of interest based on user-defined start and end points at a specified stand-off distance from the skin surface. The catheter paths are radially extended to create catheter channels that are sufficientlymore » wide to ensure smooth insertion of catheters for a safe source travel. An outer mould surface is generated to encompass the channels. The mould is also equipped with fiducial markers to ensure its reproducible placement. A surface mould applicator with eight parallel catheter channels of 4mm diameters was fabricated for the nose region of a head phantom; flexible plastic catheters of 2mm diameter were threaded through these channels maintaining 10mm catheter separations and a 5mm stand-off distance from the skin surface. The apparatus yielded 3mm thickness of mould material between channels and the skin. The mould design was exported as a stereolithography file to a Dimension SST1200es 3D printer and printed using ABS Plus plastic material. Results: The applicator closely matched its design and was found to be sufficiently rigid without deformation during repeated application on the head phantom. Catheters were easily threaded into channels carved along catheter paths. Further tests are required to evaluate feasibility of channel diameters smaller than 4mm. Conclusion: Construction of 3D-printed mould applicators show promise for use in patient specific brachytherapy of superficial lesions. Further evaluation of 3D printing techniques and materials is

  7. Prospective treatment plan-specific action limits for real-time intrafractional monitoring in surface image guided radiosurgery.

    PubMed

    Yock, Adam D; Pawlicki, Todd; Kim, Gwe-Ya

    2016-07-01

    In surface image guided radiosurgery, action limits are created to determine at what point intrafractional motion exhibited by the patient is large enough to warrant intervention. Action limit values remain constant across patients despite the fact that patient motion affects the target coverage of brain metastases differently depending on the planning technique and other treatment plan-specific factors. The purpose of this work was twofold. The first purpose was to characterize the sensitivity of single-met per iso and multimet per iso treatment plans to uncorrected patient motion. The second purpose was to describe a method to prospectively determine treatment plan-specific action limits considering this sensitivity. In their surface image guided radiosurgery technique, patient positioning is achieved with a thermoplastic mask that does not cover the patient's face. The patient's exposed face is imaged by a stereoscopic photogrammetry system. It is then compared to a reference surface and monitored throughout treatment. Seventy-two brain metastases (representing 29 patients) were used for this study. Twenty-five mets were treated individually ("single-met per iso plans"), and 47 were treated in a plan simultaneously with at least one other met ("multimet per iso plans"). For each met, the proportion of the gross tumor volume that remained within the 100% prescription isodose line was estimated under the influence of combinations of translations and rotations (0.0-3.0 mm and 0.0°-3.0°, respectively). The target volume and the prescription dose-volume were considered concentric spheres that each encompassed a volume determined from the treatment plan. Plan-specific contour plots and DVHs were created to illustrate the sensitivity of a specific lesion to uncorrected patient motion. Both single-met per iso and multimet per iso plans exhibited compromised target coverage under translations and rotations, though multimet per iso plans were considerably more sensitive

  8. Fabrication and characterization of crushed titanium-beryllium intermetallic compounds

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Hwan; Nakamichi, Masaru

    2018-01-01

    To develop a technique for the mass production of beryllide pebbles, a crushing method for the granulation of beryllides was used in this study. Two types of crushed Be12Ti pebbles were prepared using mortar-ground (MG) and planetary-ball-milled (PM) powders. A granulation yield of approximately 50 wt.% with sizes in the range of 0.85-1.18 mm was achieved. Scanning electron microscopy (SEM) images revealed that the MG pebbles exhibited larger porosity because the larger size of the powder resulted in lower density with higher porosity. However, the considerably larger fraction of fine pores in the PM pebbles resulted in an increased Brunauer-Emmett-Teller (BET) specific surface area, as clearly demonstrated by high-magnification SEM images. To evaluate the reactivity with water vapor, the weight gain and H2 generation rate were also investigated. The results suggested that the PM pebbles exhibited notably lower reactivity, weight gain, and H2 generation rate, which may be due to the dramatically decreased BET specific surface. The fine pores were filled with stable oxides followed by a significant decrease of the surface area during oxidation. Optimization was performed to improve the circularity of the crushed pebbles. Grinding tests using planetary milling without balls for different times clearly demonstrated that the circularity improved (with an estimated value of 0.8) by cutting and polishing the sharp edges; however, long-duration milling for 99 h resulted in attachment of the polished powders to the pebble surface, leading to surface color variation of the crushed pebbles.

  9. Nanospheres Encapsulating Anti-Leishmanial Drugs for Their Specific Macrophage Targeting, Reduced Toxicity, and Deliberate Intracellular Release

    PubMed Central

    Shukla, Anil Kumar; Patra, Sanjukta

    2012-01-01

    Abstract The current work focuses on the study of polymeric, biodegradable nanoparticles (NPs) for the encapsulation of doxorubicin and mitomycin C (anti-leishmanial drugs), and their efficient delivery to macrophages, the parasite's home. The biodegradable polymer methoxypoly-(ethylene glycol)-b-poly (lactic acid) (MPEG-PLA) was used to prepare polymeric NPs encapsulating doxorubicin and mitomycin C. The morphology, mean diameter, and surface area of spherical NPs were determined by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and BET surface area analysis. X-ray diffraction was performed to validate drug encapsulation. An in vitro release profile of the drugs suggested a fairly slow release. These polymeric NPs were efficiently capable of releasing drug inside macrophages at a slower pace than the free drug, which was monitored by epi-fluorescence microscopy. Encapsulation of doxorubicin and mitomycin C into NPs also decreases cellular toxicity in mouse macrophages (J774.1A). PMID:22925019

  10. Obg and Membrane Depolarization Are Part of a Microbial Bet-Hedging Strategy that Leads to Antibiotic Tolerance.

    PubMed

    Verstraeten, Natalie; Knapen, Wouter Joris; Kint, Cyrielle Ines; Liebens, Veerle; Van den Bergh, Bram; Dewachter, Liselot; Michiels, Joran Elie; Fu, Qiang; David, Charlotte Claudia; Fierro, Ana Carolina; Marchal, Kathleen; Beirlant, Jan; Versées, Wim; Hofkens, Johan; Jansen, Maarten; Fauvart, Maarten; Michiels, Jan

    2015-07-02

    Within bacterial populations, a small fraction of persister cells is transiently capable of surviving exposure to lethal doses of antibiotics. As a bet-hedging strategy, persistence levels are determined both by stochastic induction and by environmental stimuli called responsive diversification. Little is known about the mechanisms that link the low frequency of persisters to environmental signals. Our results support a central role for the conserved GTPase Obg in determining persistence in Escherichia coli in response to nutrient starvation. Obg-mediated persistence requires the stringent response alarmone (p)ppGpp and proceeds through transcriptional control of the hokB-sokB type I toxin-antitoxin module. In individual cells, increased Obg levels induce HokB expression, which in turn results in a collapse of the membrane potential, leading to dormancy. Obg also controls persistence in Pseudomonas aeruginosa and thus constitutes a conserved regulator of antibiotic tolerance. Combined, our findings signify an important step toward unraveling shared genetic mechanisms underlying persistence. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Fabrication of Water Jet Resistant and Thermally Stable Superhydrophobic Surfaces by Spray Coating of Candle Soot Dispersion.

    PubMed

    Qahtan, Talal F; Gondal, Mohammed A; Alade, Ibrahim O; Dastageer, Mohammed A

    2017-08-08

    A facile synthesis method for highly stable carbon nanoparticle (CNP) dispersion in acetone by incomplete combustion of paraffin candle flame is presented. The synthesized CNP dispersion is the mixture of graphitic and amorphous carbon nanoparticles of the size range of 20-50 nm and manifested the mesoporosity with an average pore size of 7 nm and a BET surface area of 366 m 2 g -1 . As an application of this material, the carbon nanoparticle dispersion was spray coated (spray-based coating) on a glass surface to fabricate superhydrophobic (water contact angle > 150° and sliding angle < 10 °) surfaces. The spray coated surfaces were found to exhibit much improved water jet resistance and thermal stability up to 400 °C compared to the surfaces fabricated from direct candle flame soot deposition (candle-based coating). This study proved that water jet resistant and thermally stable superhydrophobic surfaces can be easily fabricated by simple spray coating of CNP dispersion gathered from incomplete combustion of paraffin candle flame and this technique can be used for different applications with the potential for the large scale fabrication.

  12. Interfacial self-assembled functional nanoparticle array: a facile surface-enhanced Raman scattering sensor for specific detection of trace analytes.

    PubMed

    Zhang, Kun; Ji, Ji; Li, Yixin; Liu, Baohong

    2014-07-01

    Surface-enhanced Raman scattering (SERS) has proven to be promising for the detection of trace analytes; however, the precise nanofabrication of a specific and sensitive plasmonic SERS-active substrate is still a major challenge that limits the scope of its applications. In this work, gold nanoparticles are self-assembled into densely packed two-dimensional arrays at a liquid/liquid interface between dimethyl carbonate and water in the absence of template controller molecules. Both the simulation and experiment results show that the particles within these film-like arrays exhibit strong electromagnetic coupling and enable large amplification of Raman signals. In order to realize the level of sensing specificity, the surface chemistry of gold nanoparticles (Au NPs) is rationally tailored by incorporating an appropriate chemical moiety that specifically captures molecules of interest. The ease of fabrication and good uniformity make this platform ideal for in situ SERS sensing of trace targets in complex samples.

  13. Effect of interparticle interactions on size determination of zirconia and silica based systems – A comparison of SAXS, DLS, BET, XRD and TEM

    PubMed Central

    Pabisch, Silvia; Feichtenschlager, Bernhard; Kickelbick, Guido; Peterlik, Herwig

    2012-01-01

    The aim of this work is a systematic comparison of size characterisation methods for two completely different model systems of oxide nanoparticles, i.e. amorphous spherical silica and anisotropic facet-shaped crystalline zirconia. Size and/or size distribution were determined in a wide range from 5 to 70 nm using small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), nitrogen sorption (BET), X-ray diffraction (XRD) and transmission electron microscopy (TEM). A nearly perfect coincidence was observed only for SAXS and TEM for both types of particles. For zirconia nanoparticles considerable differences between different measurement methods were observed. PMID:22347721

  14. Sintering Effects on Morphology, Thermal Stability and Surface Area of Sol-Gel Derived Nano-Hydroxyapatite Powder

    NASA Astrophysics Data System (ADS)

    Kapoor, Seema; Batra, Uma; Kohli, Suchita

    2011-12-01

    Hydroxyapatite (HAP) ceramics have been recognized as substitute materials for bone and teeth in orthopedic and dentistry field due to their chemical and biological similarity to human hard tissue. The nanosized and nanocrystalline forms of HAP have great potential to revolutionize the hard tissue-engineering field, starting from bone repair and augmentation to controlled drug delivery systems. This paper reports the synthesis of biomimetic nano-hydroxyapatite (HAP) by sol-gel method using calcium nitrate tetrahydrate (CNT) and potassium dihydrogen phosphate (KDP) as calcium and phosphorus precursors, respectively to obtain a desired Ca/P ratio of 1.67. Deionized water was used as a diluting media for HAP sol preparation and ammonia was used to adjust the pH to 11. After aging, the HAP gel was dried at 55 °C and sintered to different temperatures (200 °C, 400 °C, 600 °C, 800 °C, 1000 °C and 1200 °C). The dried and sintered powders were characterized for phase composition using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The particle size and morphology was studied using transmission electron microscopy (TEM). The thermal behavior of the dried HAP nanopowder was studied in the temperature range of 55 °C to 1000 °C using thermal gravimetric analyser (TGA). The BET surface area of absorbance was determined by Nitrogen adsorption using Brunauer-Emmett-Teller (BET) method. The presence of characteristic peaks of the phosphate and OH groups in FTIR spectrums confirmed the formation of pure HAP in dried as well as sintered powders. XRD results also confirmed the formation of stoichiometric nano-HAP. Sintering revealed that with increase in temperature, both the crystallinity and crystallite size of nano-HAP particles increased. The synthesized nano-HAP powder was found to be stable upto 1000 °C without any additional phase other than HAP, whereas peak of β-TCP (tricalcium phosphate) was observed at 1200 °C. Photomicrograph of

  15. Evaluation of F+ RNA and DNA Coliphages as Source-Specific Indicators of Fecal Contamination in Surface Waters

    PubMed Central

    Cole, Dana; Long, Sharon C.; Sobsey, Mark D.

    2003-01-01

    Male-specific (F+) coliphages have been investigated as viral indicators of fecal contamination that may provide source-specific information for impacted environmental waters. This study examined the presence and proportions of the different subgroups of F+ coliphages in a variety of fecal wastes and surface waters with well-defined potential waste impacts. Municipal wastewater samples had high proportions of F+ DNA and group II and III F+ RNA coliphages. Bovine wastewaters also contained a high proportion of F+ DNA coliphages, but group I and IV F+ RNA coliphages predominated. Swine wastewaters contained approximately equal proportions of F+ DNA and RNA coliphages, and group I and III F+ RNA coliphages were most common. Waterfowl (gull and goose) feces contained almost exclusively F+ RNA coliphages of groups I and IV. No F+ coliphages were isolated from the feces of the other species examined. F+ coliphage recovery from surface waters was influenced by precipitation events and animal or human land use. There were no significant differences in coliphage density among land use categories. Significant seasonal variation was observed in the proportions of F+ DNA and RNA coliphages. Group I F+ RNA coliphages were the vast majority (90%) of those recovered from surface waters. The percentage of group I F+ RNA coliphages detected was greatest at background sites, and the percentage of group II F+ RNA coliphages was highest at human-impacted sites. Monitoring of F+ coliphage groups can indicate the presence and major sources of microbial inputs to surface waters, but environmental effects on the relative occurrence of different groups need to be considered. PMID:14602607

  16. Evaluation of F+ RNA and DNA coliphages as source-specific indicators of fecal contamination in surface waters.

    PubMed

    Cole, Dana; Long, Sharon C; Sobsey, Mark D

    2003-11-01

    Male-specific (F+) coliphages have been investigated as viral indicators of fecal contamination that may provide source-specific information for impacted environmental waters. This study examined the presence and proportions of the different subgroups of F+ coliphages in a variety of fecal wastes and surface waters with well-defined potential waste impacts. Municipal wastewater samples had high proportions of F+ DNA and group II and III F+ RNA coliphages. Bovine wastewaters also contained a high proportion of F+ DNA coliphages, but group I and IV F+ RNA coliphages predominated. Swine wastewaters contained approximately equal proportions of F+ DNA and RNA coliphages, and group I and III F+ RNA coliphages were most common. Waterfowl (gull and goose) feces contained almost exclusively F+ RNA coliphages of groups I and IV. No F+ coliphages were isolated from the feces of the other species examined. F+ coliphage recovery from surface waters was influenced by precipitation events and animal or human land use. There were no significant differences in coliphage density among land use categories. Significant seasonal variation was observed in the proportions of F+ DNA and RNA coliphages. Group I F+ RNA coliphages were the vast majority (90%) of those recovered from surface waters. The percentage of group I F+ RNA coliphages detected was greatest at background sites, and the percentage of group II F+ RNA coliphages was highest at human-impacted sites. Monitoring of F+ coliphage groups can indicate the presence and major sources of microbial inputs to surface waters, but environmental effects on the relative occurrence of different groups need to be considered.

  17. Synthesis and capacitance properties of N-doped porous carbon/NiO nanosheet composites using coal-based polyaniline as carbon and nitrogen source

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoqin; Li, Qiaoqin; Zhang, Yong; Yang, Yufei; Cao, Zhi; Xiong, Shanxin

    2018-06-01

    A novel synthesis approach of N-doped porous carbon (NPC)/NiO composites possessing some honeycomb-shaped nanoporous carbon and plentiful NiO nanosheets is exploited. First NPC/Ni composites are achieved with NPC yield of 52.9% through a catalytic pyrolysis method, using coal-based polyaniline particles prepared by an in-situ polymerization method as a carbon and nitrogen source, and nickel particles as a catalyst, respectively. Next NPC/NiO composites are achieved unexpectedly with plentiful NiO nanosheets and N content of 1.00 wt% after a liquid oxidation process. In NPC/NiO composites, porous carbon mainly presents in the amorphous state, while the incorporated nitrogen mainly presents in the form of pyrrolic N (92.9 at.%) and oxidized N (7.1 at.%). Plentiful NiO nanosheets are embedded in the pores or on the NPC surface. 33.3 at.% Ni2O3 components exist in the surface of NiO nanosheets. NPC/NiO composites possess not only rich micropores, but also significant mesopores and nanoscale macropores. The BET specific surface area, BET average pore width and BJH adsorption average pore diameter are 627.5 m2/g, 2.0 nm and 5.1 nm, respectively. NPC/NiO composites demonstrate a high specific capacitance of 404.1 F/g at 1 A/g, and a good cycling stability maintaining high specific capacitance of 212.4 F/g (84.3% of the initial capacitance) at 5 A/g after 5000 cycles of charge and discharge, attributed to some honeycomb-shaped nanopores of carbon and large specific surface area of NiO nanosheets, and the synergistic effects between electric double-layer capacitance of NPC and pseudocapacitance of NiO. This study may provide a novel approach for the value-added applications of low-rank coal.

  18. Routine systemic antibiotic prophylaxis for burn injuries in developing countries: A best evidence topic (BET)

    PubMed Central

    Stewart, Barclay T; Gyedu, Adam; Agbenorku, Pius; Amankwa, Richcane; Kushner, Adam L; Gibran, Nicole

    2015-01-01

    Background Burns are common in low- and middle-income countries (LMICs) and complicated by unhygienic conditions, malnutrition, use of high-risk homemade dressings and delayed presentation. Resultantly, use of routine systemic antibiotic prophylaxis (SAP) to prevent wound infection is common practice despite this intervention being abandoned in high-income countries due to increased antimicrobial resistance and non-bacterial suprainfection, Methods A best evidence topic (BET) was constructed using a structured protocol. The question addressed was: In LMICs, does routine use of SAP reduce burn wound infection, morbidity or mortality? Results From 704 retrieved records, 48 reports met criteria to be examined. Of those, 3 studies represented the best available evidence. Together, two randomized clinical trials (RCTs) and a retrospective cohort study reported no difference in the proportion of wound infection, any infection or length of hospital stay between SAP groups and controls. One RCT described a greater proportion of wounds infected with P. aeruginosa among SAP arms compared to controls. The studies had few participants and significant methodological weaknesses. Conclusion On the basis of limited, currently available evidence, the use of SAP cannot be recommended for patients in LMICs that present soon after burn injury. PMID:26260622

  19. Using chromate to investigate the impact of natural organics on the surface reactivity of nanoparticulate magnetite

    USGS Publications Warehouse

    Swindle, Andrew L.; Cozzarelli, Isabelle M.; Elwood Madden, Andrew S.

    2015-01-01

    Chromate was used as a chemical probe to investigate the size-dependent influence of organics on nanoparticle surface reactivity. Magnetite–chromate sorption experiments were conducted with ∼90 and ∼6 nm magnetite nanoparticles in the presence and absence of fulvic acid (FA), natural organic matter (NOM), and isolated landfill leachate (LL). Results indicated that low concentrations (1 mg/L) of organics had no noticeable impact on chromate sorption, whereas concentrations of 50 mg/L or more resulted in decreased amounts of chromate sorption. The adsorption of organics onto the magnetite surfaces interfered equally with the ability of the 6 and 90 nm particles to sorb chromate from solution, despite the greater surface area of the smaller particles. Results indicate the presence of organics did not impact the redox chemistry of the magnetite–chromate system over the duration of the experiments (8 h), nor did the organics interact with the chromate in solution. Brunauer–Emmett–Teller (BET) and scanning electron microscopy (SEM) results indicate that the organics blocked the surface reactivity by occupying surface sites on the particles. The similarity of results with FA and NOM suggests that coverage of the reactive mineral surface is the main factor behind the inhibition of surface reactivity in the presence of organics.

  20. Biotemplated synthesis of high specific surface area copper-doped hollow spherical titania and its photocatalytic research for degradating chlorotetracycline

    NASA Astrophysics Data System (ADS)

    Bu, Dan; Zhuang, Huisheng

    2013-01-01

    Copper-doped titania (Cu/TiO2) hollow microspheres were fabricated using the rape pollen as biotemplates via an improved sol-gel method and a followed calcinations process. In the fabricated process, a titanium(IV)-isopropoxide-based sol directly coated onto the surface of rape pollen. Subsequently, after calcinations, rape pollen was removed by high temperature and the hollow microsphere structure was retained. The average diameter of as-obtained hollow microspheres is 15-20 μm and the thickness of shell is approximately 0.6 μm. Knowing from XRD results, the main crystal phase of microspheres is anatase, coupled with rutile. The specific surface area varied between 141.80 m2/g and 172.51 m2/g. This hollow sphere photocatalysts with high specific surface area exhibited stronger absorption ability and higher photoactivity, stimulated by visible light. The degradation process of chlortetracycline (CTC) solution had been studied. The degradated results indicate that CTC could be effective degradated by fabricated hollow spherical materials. And the intermediate products formed in the photocatalytic process had been identified.

  1. Identifying and tracing potential energy surfaces of electronic excitations with specific character via their transition origins: application to oxirane.

    PubMed

    Li, Jian-Hao; Zuehlsdorff, T J; Payne, M C; Hine, N D M

    2015-05-14

    We show that the transition origins of electronic excitations identified by quantified natural transition orbital (QNTO) analysis can be employed to connect potential energy surfaces (PESs) according to their character across a wide range of molecular geometries. This is achieved by locating the switching of transition origins of adiabatic potential surfaces as the geometry changes. The transition vectors for analysing transition origins are provided by linear response time-dependent density functional theory (TDDFT) calculations under the Tamm-Dancoff approximation. We study the photochemical CO ring opening of oxirane as an example and show that the results corroborate the traditional Gomer-Noyes mechanism derived experimentally. The knowledge of specific states for the reaction also agrees well with that given by previous theoretical work using TDDFT surface-hopping dynamics that was validated by high-quality quantum Monte Carlo calculations. We also show that QNTO can be useful for considerably larger and more complex systems: by projecting the excitations to those of a reference oxirane molecule, the approach is able to identify and analyse specific excitations of a trans-2,3-diphenyloxirane molecule.

  2. Biomaterial design for specific cellular interactions: Role of surface functionalization and geometric features

    NASA Astrophysics Data System (ADS)

    Kolhar, Poornima

    The areas of drug delivery and tissue engineering have experienced extraordinary growth in recent years with the application of engineering principles and their potential to support and improve the field of medicine. The tremendous progress in nanotechnology and biotechnology has lead to this explosion of research and development in biomedical applications. Biomaterials can now be engineered at a nanoscale and their specific interactions with the biological tissues can be modulated. Various design parameters are being established and researched for design of drug-delivery carriers and scaffolds to be implanted into humans. Nanoparticles made from versatile biomaterial can deliver both small-molecule drugs and various classes of bio-macromolecules, such as proteins and oligonucleotides. Similarly in the field of tissue engineering, current approaches emphasize nanoscale control of cell behavior by mimicking the natural extracellular matrix (ECM) unlike, traditional scaffolds. Drug delivery and tissue engineering are closely connected fields and both of these applications require materials with exceptional physical, chemical, biological, and biomechanical properties to provide superior therapy. In the current study the surface functionalization and the geometric features of the biomaterials has been explored. In particular, a synthetic surface for culture of human embryonic stem cells has been developed, demonstrating the importance of surface functionalization in maintaining the pluripotency of hESCs. In the second study, the geometric features of the drug delivery carriers are investigated and the polymeric nanoneedles mediated cellular permeabilization and direct cytoplasmic delivery is reported. In the third study, the combined effect of surface functionalization and geometric modification of carriers for vascular targeting is enunciated. These studies illustrate how the biomaterials can be designed to achieve various cellular behaviors and control the

  3. Cation specific binding with protein surface charges

    PubMed Central

    Hess, Berk; van der Vegt, Nico F. A.

    2009-01-01

    Biological organization depends on a sensitive balance of noncovalent interactions, in particular also those involving interactions between ions. Ion-pairing is qualitatively described by the law of “matching water affinities.” This law predicts that cations and anions (with equal valence) form stable contact ion pairs if their sizes match. We show that this simple physical model fails to describe the interaction of cations with (molecular) anions of weak carboxylic acids, which are present on the surfaces of many intra- and extracellular proteins. We performed molecular simulations with quantitatively accurate models and observed that the order K+ < Na+ < Li+ of increasing binding affinity with carboxylate ions is caused by a stronger preference for forming weak solvent-shared ion pairs. The relative insignificance of contact pair interactions with protein surfaces indicates that thermodynamic stability and interactions between proteins in alkali salt solutions is governed by interactions mediated through hydration water molecules. PMID:19666545

  4. Evaluation of non-specific binding suppression schemes for neutravidin and alkaline phosphatase at the surface of reticulated vitreous carbon electrodes.

    PubMed

    Shedge, Hemangi Y; Creager, Stephen E

    2010-01-11

    Non-specific binding (NSB) of high-molecular-weight proteins onto electrode surfaces can complicate the application of electroanalytical techniques to clinical and environmental research, particularly in biosensor applications. We present herein various strategies to modify the surface of reticulated vitreous carbon (RVC) electrodes to suppress non-specific binding of biomolecules onto its surface. Non-specific binding and specific binding (SB) of two enzyme conjugates, neutravidin-alkaline phosphatase (NA-ALP) and biotinylated alkaline phosphatase (B-ALP), and also neutravidin itself, were studied using hydroquinone diphosphate (HQDP) as an enzyme substrate for ALP inside the pores of RVC electrodes that had been subjected to various modification schemes. The extent of NSB and SB of these biomolecules inside RVC pores was assessed by measuring the initial rate of generation of an electroactive product, hydroquinone (HQ), of the enzyme-catalyzed reaction, using linear scan voltammetry (LSV) for HQ detection. Electrodes functionalized with phenylacetic acid and poly(ethylene glycol) (PEG) showed low NSB and high SB (when biotin capture ligands were included in the modification scheme) in comparison with unmodified electrodes and RVC electrodes modified in other ways. A simple sandwich bioassay for neutravidin was performed on the RVC electrode with the lowest NSB. A concentration detection limit of 52+/-2 ng mL(-1) and an absolute detection limit of 5.2+/-0.2 ng were achieved for neutravidin when this assay was performed using a 100 microL sample size.

  5. A microbial-mineralization approach for syntheses of iron oxides with a high specific surface area.

    PubMed

    Yagita, Naoki; Oaki, Yuya; Imai, Hiroaki

    2013-04-02

    Of minerals and microbes: A microbial-mineralization-inspired approach was used to facilitate the syntheses of iron oxides with a high specific surface area, such as 253 m(2)g(-1) for maghemite (γ-Fe(2)O(3)) and 148 m(2)g(-1) for hematite (α-Fe(2)O(3)). These iron oxides can be applied to electrode material of lithium-ion batteries, adsorbents, and catalysts. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Growth of porous anodized alumina on the sputtered aluminum films with 2D-3D morphology for high specific surface area

    NASA Astrophysics Data System (ADS)

    Liao, M. W.; Chung, C. K.

    2014-08-01

    The porous anodic aluminum oxide (AAO) with high-aspect-ratio pore channels is widely used as a template for fabricating nanowires or other one-dimensional (1D) nanostructures. The high specific surface area of AAO can also be applied to the super capacitor and the supporting substrate for catalysis. The rough surface could be helpful to enhance specific surface area but it generally results in electrical field concentration even to ruin AAO. In this article, the aluminum (Al) films with the varied 2D-3D morphology on Si substrates were prepared using magnetron sputtering at a power of 50 W-185 W for 1 h at a working pressure of 2.5 × 10-1 Pa. Then, AAO was fabricated from the different Al films by means of one-step hybrid pulse anodizing (HPA) between the positive 40 V and the negative -2 V (1 s:1 s) for 3 min in 0.3 M oxalic acid at a room temperature. The microstructure and morphology of Al films were characterized by X-ray diffraction, scanning electron microscope and atomic force microscope, respectively. Some hillocks formed at the high target power could be attributed to the grain texture growth in the normal orientation of Al(1 1 1). The 3D porous AAO structure which is different from the conventional 2D planar one has been successfully demonstrated using HPA on the film with greatly rough hillock-surface formed at the highest power of 185 W. It offers a potential application of the new 3D AAO to high specific surface area devices.

  7. Specification for a surface-search radar-detection-range model

    NASA Astrophysics Data System (ADS)

    Hattan, Claude P.

    1990-09-01

    A model that predicts surface-search radar detection range versus a variety of combatants has been developed at the Naval Ocean Systems Center. This model uses a simplified ship radar cross section (RCS) model and the U.S. Navy Oceanographic and Atmospheric Mission Library Standard Electromagnetic Propagation Model. It provides the user with a method of assessing the effects of the environment of the performance of a surface-search radar system. The software implementation of the model is written in ANSI FORTRAN 77, with MIL-STD-1753 extensions. The program provides the user with a table of expected detection ranges when the model is supplied with the proper environmental radar system inputs. The target model includes the variation in RCS as a function of aspect angle and the distribution of reflected radar energy as a function of height above the waterline. The modeled propagation effects include refraction caused by a multisegmented refractivity profile, sea-surface roughness caused by local winds, evaporation ducting, and surface-based ducts caused by atmospheric layering.

  8. Specific effects of surface carboxyl groups on anionic polystyrene particles in their interactions with mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Jiang, Xiue; Musyanovych, Anna; Röcker, Carlheinz; Landfester, Katharina; Mailänder, Volker; Nienhaus, G. Ulrich

    2011-05-01

    Nanoparticle uptake by living cells is governed by chemical interactions between functional groups on the nanoparticle as well as the receptors on cell surfaces. Here we have investigated the uptake of anionic polystyrene (PS) nanoparticles of ~100 nm diameter by mesenchymal stem cells (MSCs) using spinning-disk confocal optical microscopy combined with a quantitative analysis of the fluorescence images. Two types of anionic PS nanoparticles with essentially identical sizes and ζ-potentials were employed in this study, carboxyl-functionalized nanoparticles (CPS) and plain PS nanoparticles, both coated with anionic detergent for stabilization. CPS nanoparticles were observed to internalize more rapidly and accumulate to a much higher level than plain PS nanoparticles. The relative importance of different uptake mechanisms for the two types of nanoparticles was investigated by using specific inhibitors. CPS nanoparticles were internalized mainly via the clathrin-mediated mechanism, whereas plain PS nanoparticles mainly utilized the macropinocytosis pathway. The pronounced difference in the internalization behavior of CPS and plain PS nanoparticles points to a specific interaction of the carboxyl group with receptors on the cell surface.

  9. High prevalence of sensitization to gibberellin-regulated protein (peamaclein) in fruit allergies with negative immunoglobulin E reactivity to Bet v 1 homologs and profilin: Clinical pattern, causative fruits and cofactor effect of gibberellin-regulated protein allergy.

    PubMed

    Inomata, Naoko; Miyakawa, Mami; Aihara, Michiko

    2017-07-01

    Gibberellin-regulated protein (GRP) is a new allergen in peach allergy, with an amino acid sequence very well conserved through several botanical species. We investigated the allergenicity of GRP in fruit allergies other than peaches and identified the clinical characteristics of fruit allergy patients with GRP sensitization. One hundred consecutive Japanese patients with fruit allergies were enrolled in the present study. To identify the features of GRP sensitization, we selected patients with negative ImmunoCAP results for Bet v 1 homologs and profilin, which are marker allergens for pollen-food allergy syndrome (PFAS), or lipid transfer protein. These patients underwent specific immunoglobulin E measurements by enzyme-linked immunosorbent assay (ELISA) and skin prick tests (SPT) using purified nPru p 7. Twenty of 100 consecutive patients with fruit allergies had negative ImmunoCAP results for Bet v 1 homologs and profilin. Thirteen (65.0%) of the 20 patients had positive ELISA and/or SPT results using nPru p 7, whereas one of the 20 patients had positive ImmunoCAP results for Pru p 3. In 13 nPru p 7-sensitized patients, the causative foods were peaches (92.3%), apricots (61.5%), oranges (46.2%) and apples (30.8%). Ten patients (76.9%) had multiple causative fruits. Frequent symptoms included facial edema (92.3%) and laryngeal tightness (66.7%). In eight patients (61.5%), exercise or aspirin intake enhanced the allergic reaction onset as cofactors. The prevalence of GRP sensitization was high in Japanese fruit allergy patients except for PFAS patients. In conclusion, GRP-sensitized patients may have allergies to multiple fruits and may show peculiar characteristics such as facial swelling and cofactor dependence. © 2017 Japanese Dermatological Association.

  10. Fragment-Based, Structure-Enabled Discovery of Novel Pyridones and Pyridone Macrocycles as Potent Bromodomain and Extra-Terminal Domain (BET) Family Bromodomain Inhibitors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Le; Pratt, John K.; Soltwedel, Todd

    Members of the BET family of bromodomain containing proteins have been identified as potential targets for blocking proliferation in a variety of cancer cell lines. A two-dimensional NMR fragment screen for binders to the bromodomains of BRD4 identified a phenylpyridazinone fragment with a weak binding affinity (1, Ki = 160 μM). SAR investigation of fragment 1, aided by X-ray structure-based design, enabled the synthesis of potent pyridone and macrocyclic pyridone inhibitors exhibiting single digit nanomolar potency in both biochemical and cell based assays. Advanced analogs in these series exhibited high oral exposures in rodent PK studies and demonstrated significant tumormore » growth inhibition efficacy in mouse flank xenograft models.« less

  11. 40 CFR 761.372 - Specific requirements for relatively clean surfaces.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... that each 900 cm2 (1 square foot) of the surface is always very wet for 1 minute. Wipe smooth surfaces with a solvent-soaked, disposable absorbent pad such that each 900 cm2 (1 square foot) is wiped for 1 minute. Any surface square foot shall also be wiped for 1 minute. Wipe, mop, and/or sorb the solvent...

  12. 40 CFR 761.372 - Specific requirements for relatively clean surfaces.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... that each 900 cm2 (1 square foot) of the surface is always very wet for 1 minute. Wipe smooth surfaces with a solvent-soaked, disposable absorbent pad such that each 900 cm2 (1 square foot) is wiped for 1 minute. Any surface square foot shall also be wiped for 1 minute. Wipe, mop, and/or sorb the solvent...

  13. 21 CFR 660.44 - Specificity.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.44 Specificity. Each filling of the product shall be specific for Hepatitis B Surface Antigen as determined by...

  14. 21 CFR 660.44 - Specificity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.44 Specificity. Each filling of the product shall be specific for Hepatitis B Surface Antigen as determined by...

  15. 21 CFR 660.44 - Specificity.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.44 Specificity. Each filling of the product shall be specific for Hepatitis B Surface Antigen as determined by...

  16. 21 CFR 660.44 - Specificity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.44 Specificity. Each filling of the product shall be specific for Hepatitis B Surface Antigen as determined by...

  17. Automatic construction of subject-specific human airway geometry including trifurcations based on a CT-segmented airway skeleton and surface

    PubMed Central

    Miyawaki, Shinjiro; Tawhai, Merryn H.; Hoffman, Eric A.; Wenzel, Sally E.; Lin, Ching-Long

    2016-01-01

    We propose a method to construct three-dimensional airway geometric models based on airway skeletons, or centerlines (CLs). Given a CT-segmented airway skeleton and surface, the proposed CL-based method automatically constructs subject-specific models that contain anatomical information regarding branches, include bifurcations and trifurcations, and extend from the trachea to terminal bronchioles. The resulting model can be anatomically realistic with the assistance of an image-based surface; alternatively a model with an idealized skeleton and/or branch diameters is also possible. This method systematically identifies and classifies trifurcations to successfully construct the models, which also provides the number and type of trifurcations for the analysis of the airways from an anatomical point of view. We applied this method to 16 normal and 16 severe asthmatic subjects using their computed tomography images. The average distance between the surface of the model and the image-based surface was 11% of the average voxel size of the image. The four most frequent locations of trifurcations were the left upper division bronchus, left lower lobar bronchus, right upper lobar bronchus, and right intermediate bronchus. The proposed method automatically constructed accurate subject-specific three-dimensional airway geometric models that contain anatomical information regarding branches using airway skeleton, diameters, and image-based surface geometry. The proposed method can construct (i) geometry automatically for population-based studies, (ii) trifurcations to retain the original airway topology, (iii) geometry that can be used for automatic generation of computational fluid dynamics meshes, and (iv) geometry based only on a skeleton and diameters for idealized branches. PMID:27704229

  18. Mineral Ecology: Surface Specific Colonization and Geochemical Drivers of Biofilm Accumulation, Composition, and Phylogeny

    PubMed Central

    Jones, Aaron A.; Bennett, Philip C.

    2017-01-01

    This study tests the hypothesis that surface composition influences microbial community structure and growth of biofilms. We used laboratory biofilm reactors (inoculated with a diverse subsurface community) to explore the phylogenetic and taxonomic variability in microbial communities as a function of surface type (carbonate, silicate, aluminosilicate), media pH, and carbon and phosphate availability. Using high-throughput pyrosequencing, we found that surface type significantly controlled ~70–90% of the variance in phylogenetic diversity regardless of environmental pressures. Consistent patterns also emerged in the taxonomy of specific guilds (sulfur-oxidizers/reducers, Gram-positives, acidophiles) due to variations in media chemistry. Media phosphate availability was a key property associated with variation in phylogeny and taxonomy of whole reactors and was negatively correlated with biofilm accumulation and α-diversity (species richness and evenness). However, mineral-bound phosphate limitations were correlated with less biofilm. Carbon added to the media was correlated with a significant increase in biofilm accumulation and overall α-diversity. Additionally, planktonic communities were phylogenetically distant from those in biofilms. All treatments harbored structurally (taxonomically and phylogenetically) distinct microbial communities. Selective advantages within each treatment encouraged growth and revealed the presence of hundreds of additional operational taxonomix units (OTU), representing distinct consortiums of microorganisms. Ultimately, these results provide evidence that mineral/rock composition significantly influences microbial community structure, diversity, membership, phylogenetic variability, and biofilm growth in subsurface communities. PMID:28400754

  19. 21 CFR 660.5 - Specificity.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Antibody to Hepatitis B Surface Antigen § 660.5 Specificity. Each filling of the product shall be specific for antibody to hepatitis B surface antigen, as...

  20. 21 CFR 660.5 - Specificity.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Antibody to Hepatitis B Surface Antigen § 660.5 Specificity. Each filling of the product shall be specific for antibody to hepatitis B surface antigen, as...