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Sample records for arylamine n-acetyltransferase activity

  1. Evidence for arylamine N-acetyltransferase in Hymenolepis nana.

    Science.gov (United States)

    Chung, J G; Kuo, H M; Wu, L T; Lai, J M; Lee, J H; Hung, C F

    1997-02-01

    N-acetyltransferase activities with p-aminobenzoic acid and 2-aminofluorene were determined in Hymenolepis nana, a cestode found in the intestine of the Sprague-Dawley rats. The N-acetyltransferase activity was determined using an acetyl CoA recycling assay and high pressure liquid chromatography. The N-acetyltransferase activities from a number of Hymenolepis nana whole tissue homogenizations were found to be 2.83 +/- 0.31 nmole/min/mg for 2-aminofluorene and 2.07 +/- 0.24 nmole/min/mg for p-aminobenzoic acid. The apparent Km and Vmax were 1.06 +/- 0.38 mM and 8.92 +/- 1.46 nmol/min/mg for 2-aminofluorene, and 2.16 +/- 0.19 mM and 12.68 +/- 2.26 nmol/min/mg for p-aminobenzoic acid. The optimal pH value for the enzyme activity was pH 8.0 for both substrates tested. The optimal temperature for enzyme activity was 37 degrees C for both substrates. The N-acetyltransferase activity was inhibited by iodacetamide. At 0.25 mM iodacetamide the activity was reduced 50% and 1.0 mM iodacetamide inhibited activity more than 90%. Among a series of divalent cations and salts, Fe2+, Ca2+ and Zn2+ were demonstrated to be the most potent inhibi-tors. Among the protease inhibitors, only ethylenediaminetetraacetic acid significantly protected N-acetyltransferase. Iodoacetate, in contrast to other agents, markedly inhibited N-acetyltransferase activity. This is the first demonstration of acetyl CoA:arylamine N-acetyltransferase activity in a cestode and extends the number of phyla in which this activity has been found.

  2. From arylamine N-acetyltransferase to folate-dependent acetyl CoA hydrolase: impact of folic acid on the activity of (HUMAN)NAT1 and its homologue (MOUSE)NAT2.

    Science.gov (United States)

    Laurieri, Nicola; Dairou, Julien; Egleton, James E; Stanley, Lesley A; Russell, Angela J; Dupret, Jean-Marie; Sim, Edith; Rodrigues-Lima, Fernando

    2014-01-01

    Acetyl Coenzyme A-dependent N-, O- and N,O-acetylation of aromatic amines and hydrazines by arylamine N-acetyltransferases is well characterised. Here, we describe experiments demonstrating that human arylamine N-acetyltransferase Type 1 and its murine homologue (Type 2) can also catalyse the direct hydrolysis of acetyl Coenzyme A in the presence of folate. This folate-dependent activity is exclusive to these two isoforms; no acetyl Coenzyme A hydrolysis was found when murine arylamine N-acetyltransferase Type 1 or recombinant bacterial arylamine N-acetyltransferases were incubated with folate. Proton nuclear magnetic resonance spectroscopy allowed chemical modifications occurring during the catalytic reaction to be analysed in real time, revealing that the disappearance of acetyl CH3 from acetyl Coenzyme A occurred concomitantly with the appearance of a CH3 peak corresponding to that of free acetate and suggesting that folate is not acetylated during the reaction. We propose that folate is a cofactor for this reaction and suggest it as an endogenous function of this widespread enzyme. Furthermore, in silico docking of folate within the active site of human arylamine N-acetyltransferase Type 1 suggests that folate may bind at the enzyme's active site, and facilitate acetyl Coenzyme A hydrolysis. The evidence presented in this paper adds to our growing understanding of the endogenous roles of human arylamine N-acetyltransferase Type 1 and its mouse homologue and expands the catalytic repertoire of these enzymes, demonstrating that they are by no means just xenobiotic metabolising enzymes but probably also play an important role in cellular metabolism. These data, together with the characterisation of a naphthoquinone inhibitor of folate-dependent acetyl Coenzyme A hydrolysis by human arylamine N-acetyltransferase Type 1/murine arylamine N-acetyltransferase Type 2, open up a range of future avenues of exploration, both for elucidating the developmental role of these

  3. From arylamine N-acetyltransferase to folate-dependent acetyl CoA hydrolase: impact of folic acid on the activity of (HUMANNAT1 and its homologue (MOUSENAT2.

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    Nicola Laurieri

    Full Text Available Acetyl Coenzyme A-dependent N-, O- and N,O-acetylation of aromatic amines and hydrazines by arylamine N-acetyltransferases is well characterised. Here, we describe experiments demonstrating that human arylamine N-acetyltransferase Type 1 and its murine homologue (Type 2 can also catalyse the direct hydrolysis of acetyl Coenzyme A in the presence of folate. This folate-dependent activity is exclusive to these two isoforms; no acetyl Coenzyme A hydrolysis was found when murine arylamine N-acetyltransferase Type 1 or recombinant bacterial arylamine N-acetyltransferases were incubated with folate. Proton nuclear magnetic resonance spectroscopy allowed chemical modifications occurring during the catalytic reaction to be analysed in real time, revealing that the disappearance of acetyl CH3 from acetyl Coenzyme A occurred concomitantly with the appearance of a CH3 peak corresponding to that of free acetate and suggesting that folate is not acetylated during the reaction. We propose that folate is a cofactor for this reaction and suggest it as an endogenous function of this widespread enzyme. Furthermore, in silico docking of folate within the active site of human arylamine N-acetyltransferase Type 1 suggests that folate may bind at the enzyme's active site, and facilitate acetyl Coenzyme A hydrolysis. The evidence presented in this paper adds to our growing understanding of the endogenous roles of human arylamine N-acetyltransferase Type 1 and its mouse homologue and expands the catalytic repertoire of these enzymes, demonstrating that they are by no means just xenobiotic metabolising enzymes but probably also play an important role in cellular metabolism. These data, together with the characterisation of a naphthoquinone inhibitor of folate-dependent acetyl Coenzyme A hydrolysis by human arylamine N-acetyltransferase Type 1/murine arylamine N-acetyltransferase Type 2, open up a range of future avenues of exploration, both for elucidating the

  4. Piperidinols that show anti-tubercular activity as inhibitors of arylamine N-acetyltransferase: an essential enzyme for mycobacterial survival inside macrophages.

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    Areej Abuhammad

    Full Text Available Latent M. tuberculosis infection presents one of the major obstacles in the global eradication of tuberculosis (TB. Cholesterol plays a critical role in the persistence of M. tuberculosis within the macrophage during latent infection. Catabolism of cholesterol contributes to the pool of propionyl-CoA, a precursor that is incorporated into cell-wall lipids. Arylamine N-acetyltransferase (NAT is encoded within a gene cluster that is involved in the cholesterol sterol-ring degradation and is essential for intracellular survival. The ability of the NAT from M. tuberculosis (TBNAT to utilise propionyl-CoA links it to the cholesterol-catabolism pathway. Deleting the nat gene or inhibiting the NAT enzyme prevents intracellular survival and results in depletion of cell-wall lipids. TBNAT has been investigated as a potential target for TB therapies. From a previous high-throughput screen, 3-benzoyl-4-phenyl-1-methylpiperidinol was identified as a selective inhibitor of prokaryotic NAT that exhibited antimycobacterial activity. The compound resulted in time-dependent irreversible inhibition of the NAT activity when tested against NAT from M. marinum (MMNAT. To further evaluate the antimycobacterial activity and the NAT inhibition of this compound, four piperidinol analogues were tested. All five compounds exert potent antimycobacterial activity against M. tuberculosis with MIC values of 2.3-16.9 µM. Treatment of the MMNAT enzyme with this set of inhibitors resulted in an irreversible time-dependent inhibition of NAT activity. Here we investigate the mechanism of NAT inhibition by studying protein-ligand interactions using mass spectrometry in combination with enzyme analysis and structure determination. We propose a covalent mechanism of NAT inhibition that involves the formation of a reactive intermediate and selective cysteine residue modification. These piperidinols present a unique class of antimycobacterial compounds that have a novel mode of action

  5. Insights into the phylogeny or arylamine N-acetyltransferases in fungi.

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    Martins, Marta; Dairou, Julien; Rodrigues-Lima, Fernando; Dupret, Jean-Marie; Silar, Philippe

    2010-08-01

    Previous studies have shown that Eumycetes fungi can acylate arylamine thanks to arylamine N-acetyltransferases, xenobiotic-metabolizing enzymes also found in animals and bacteria. In this article, we present the results of mining 96 available fungal genome sequences for arylamine N-acetyltransferase genes and propose their phylogeny. The filamentous Pezizomycotina are shown to possess many putative N-acetyltransferases, whilst these are often lacking in other fungal groups. The evolution of the N-acetyltransferases is best explained by the presence of at least one gene in the opisthokont ancestor of the fungi and animal kingdoms, followed by recurrent gene losses and gene duplications. A possible horizontal gene transfer event may have occurred from bacteria to the basidiomycetous yeast Malassezia globosa.

  6. Density Functional Theory Study on the Histidine-assisted Mechanism of Arylamine N-Acetyltransferase Acetylation

    Institute of Scientific and Technical Information of China (English)

    QIAO Qing-An; GAO Shan-Min; JIN Yue-Qing; CHEN Xin; SUN Xiao-Min; YANG Chuan-Lu

    2008-01-01

    Arylamine N-acetyltransferases (NATs, EC 2.3.1.5) catalyze the N-acetylation of primary arylamines, and play a key role in the biotransformation and metabolism of drugs, carcinogens, etc.In this paper, three possible reaction mechanisms are investigated and the results indicate that if the acetyl group directly transfers from the donor to the acceptor, the high activation energies will make it hard to obtain the target products.When using histidine to mediate the acetylation process, these energies will drop in the 15~45 kJ/mol range.If the histidine residue is protonated, the corresponding energies will be decreased by about 35~87 kJ/mol.The calculations predict an enzymatic acetylation mechanism that undergoes a thiolate-imidazolium pair, which agrees with the experimental results very well.

  7. Kinetic characterisation of arylamine N-acetyltransferase from Pseudomonas aeruginosa

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    Sim Edith

    2007-03-01

    Full Text Available Abstract Background Arylamine N-acetyltransferases (NATs are important drug- and carcinogen-metabolising enzymes that catalyse the transfer of an acetyl group from a donor, such as acetyl coenzyme A, to an aromatic or heterocyclic amine, hydrazine, hydrazide or N-hydroxylamine acceptor substrate. NATs are found in eukaryotes and prokaryotes, and they may also have an endogenous function in addition to drug metabolism. For example, NAT from Mycobacterium tuberculosis has been proposed to have a role in cell wall lipid biosynthesis, and is therefore of interest as a potential drug target. To date there have been no studies investigating the kinetic mechanism of a bacterial NAT enzyme. Results We have determined that NAT from Pseudomonas aeruginosa, which has been described as a model for NAT from M. tuberculosis, follows a Ping Pong Bi Bi kinetic mechanism. We also describe substrate inhibition by 5-aminosalicylic acid, in which the substrate binds both to the free form of the enzyme and the acetyl coenzyme A-enzyme complex in non-productive reaction pathways. The true kinetic parameters for the NAT-catalysed acetylation of 5-aminosalicylic acid with acetyl coenzyme A as the co-factor have been established, validating earlier approximations. Conclusion This is the first reported study investigating the kinetic mechanism of a bacterial NAT enzyme. Additionally, the methods used herein can be applied to investigations of the interactions of NAT enzymes with new chemical entities which are NAT ligands. This is likely to be useful in the design of novel potential anti-tubercular agents.

  8. Inflammatory cytokines suppress arylamine N-acetyltransferase 1 in cholangiocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To evaluate the effect of inflammatory cytokines on arylamine N-acetyltransferase 1 (NAT1), which is a phase-Ⅱ enzyme involved in the biotransformation of aromatic and heterocyclic amines found in food, drugs and the environment.METHODS: Human cholangiocarcinoma KKU-100 cells were treated with a mixture of proinflammatory cytokines (interferon-y, interleukin-1β and tumor necrosis factor-α)for 48 h, and the effect on NAT1 activity was assessed by high performance liquid chromatography, while NAT1 expression was determined by reverse-transcription polymerase chain reaction. The oxidative stress on the cells was examined by the formation of nitric oxide,superoxide anion and glutathione (GSH) levels. The cells were also treated with S-nitroso-glutathione (GSNO), a nitric oxide donor, to see if the responses were similar to those obtained with the inflammatory cytokines.RESULTS: Cytokines suppressed NAT1 activity,reducing the Vmax without affecting the Km. Cytokines also had a significant impact on the induction of nitric oxide production and in reducing the redox ratios of glutathione (GSH) and GSH disulfide. Treatment with GSNO for 2-48 h reduced NAT1 activity without affecting the GSH ratio. Moreover, inflammatory cytokines and GSNO suppressed NAT1 mRNA expression.CONCLUSION: These findings indicate an association between inflammation and suppression of NAT1, which perhaps contributes to chemical-mediated toxicity and carcinogenesis.

  9. Polymorphisms of arylamine N-acetyltransferase2 and risk of lung and colorectal cancer

    OpenAIRE

    Amjad Mahasneh; Amal Jubaili; Ahmed El Bateiha; Mohammad Al-Ghazo; Ismail Matalka; Mousa Malkawi

    2012-01-01

    The arylamine N-acetyltransferase 2 (NAT2) enzymes detoxify a wide range of naturally occurring xenobiotics including carcinogens and drugs. Point mutations in the NAT2 gene result in the variant alleles M1 (NAT2 *5A), M2 (NAT2*6A), M3 (NAT2*7) and M4 (NAT2 *14A) from the wild-type WT (NAT2 *4) allele. The current study was aimed at screening genetic polymorphisms of NAT2 gene in 49 lung cancer patients, 54 colorectal cancer patients and 99 cancer-free controls, using PCR-RFLP. There were sig...

  10. Some properties of acetyl-CoA:arylamine N-acetyltransferase (EC 2. 3. 1. 5) from rat pineal gland

    Energy Technology Data Exchange (ETDEWEB)

    Morton, D.J. (Department of Pharmacy, University of Zimbabwe, Harare, Zimbabwe)

    N-acetylation of serotonin to N-acetylserotonin in the pineal gland is catalysed by acetyl-CoA:arylamine N-acetyltransferase (SNAT). The present investigation was an attempt to design an assay technique which would permit sensitive evaluation of SNAT in order to evaluate some kinetic properties of the enzyme.

  11. The Bacillus anthracis arylamine N-acetyltransferase ((BACAN)NAT1) that inactivates sulfamethoxazole, reveals unusual structural features compared with the other NAT isoenzymes.

    Science.gov (United States)

    Pluvinage, Benjamin; Li de la Sierra-Gallay, Inés; Kubiak, Xavier; Xu, Ximing; Dairou, Julien; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2011-12-15

    Arylamine N-acetyltransferases (NATs) are xenobiotic-metabolizing enzymes that biotransform arylamine drugs. The Bacillus anthracis (BACAN)NAT1 enzyme affords increased resistance to the antibiotic sulfamethoxazole through its acetylation. We report the structure of (BACAN)NAT1. Unexpectedly, endogenous coenzymeA was present in the active site. The structure suggests that, contrary to the other prokaryotic NATs, (BACAN)NAT1 possesses a 14-residue insertion equivalent to the "mammalian insertion", a structural feature considered unique to mammalian NATs. Moreover, (BACAN)NAT1 structure shows marked differences in the mode of binding and location of coenzymeA when compared to the other NATs. This suggests that the mechanisms of cofactor recognition by NATs is more diverse than expected and supports the cofactor-binding site as being a unique subsite to target in drug design against bacterial NATs.

  12. Insights into the O-Acetylation Reaction of Hydroxylated Heterocyclic Amines by Human Arylamine N-Acetyltransferases: A Computational Study

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    Lau, E Y; Felton, J S; Lightstone, F C

    2006-06-06

    A computational study was performed to better understand the differences between human arylamine N-acetyltransferase (NAT) 1 and 2. Homology models were constructed from available crystal structures and comparisons of the active site residues 125, 127, and 129 for these two enzymes provide insight into observed substrate differences. The NAT2 model provided a basis for understanding how some of the common mutations may affect the structure of the protein. Molecular dynamics simulations of the human NAT models and the template structure (NAT from Mycobacterium smegmatis) were performed and showed the models to be stable and reasonable. Docking studies of hydroxylated heterocyclic amines in the models of NAT1 and NAT2 probed the differences exhibited by these two proteins with mutagenic agents. The hydroxylated heterocyclic amines were only able to fit into the NAT2 active site, and an alternative binding site by the P-loop was found using our models and will be discussed. Additionally, quantum mechanical calculations were performed to study the O-acetylation reaction of the hydroxylated heterocyclic amines N-OH MeIQx and N-OH PhIP. This study has given us insight into why there are substrate differences among isoenzymes and explains some of the polymorphic activity differences.

  13. Arylamine N-acetyltransferase 2 (NAT2 genetic diversity and traditional subsistence: a worldwide population survey.

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    Audrey Sabbagh

    Full Text Available Arylamine N-acetyltransferase 2 (NAT2 is involved in human physiological responses to a variety of xenobiotic compounds, including common therapeutic drugs and exogenous chemicals present in the diet and the environment. Many questions remain about the evolutionary mechanisms that have led to the high prevalence of slow acetylators in the human species. Evidence from recent surveys of NAT2 gene variation suggests that NAT2 slow-causing variants might have become targets of positive selection as a consequence of the shift in modes of subsistence and lifestyle in human populations in the last 10,000 years. We aimed to test more extensively the hypothesis that slow acetylation prevalence in humans is related to the subsistence strategy adopted by the past populations. To this end, published frequency data on the most relevant genetic variants of NAT2 were collected from 128 population samples (14,679 individuals representing different subsistence modes and dietary habits, allowing a thorough analysis at both a worldwide and continent scale. A significantly higher prevalence of the slow acetylation phenotype was observed in populations practicing farming (45.4% and herding (48.2% as compared to populations mostly relying on hunting and gathering (22.4% (P = 0.0007. This was closely mirrored by the frequency of the slow 590A variant that was found to occur at a three-fold higher frequency in food producers (25% as compared to hunter-gatherers (8%. These findings are consistent with the hypothesis that the Neolithic transition to subsistence economies based on agricultural and pastoral resources modified the selective regime affecting the NAT2 acetylation pathway. Furthermore, the vast amount of data collected enabled us to provide a comprehensive and up-to-date description of NAT2 worldwide genetic diversity, thus building up a useful resource of frequency data for further studies interested in epidemiological or anthropological research

  14. Polymorphisms of arylamine N-acetyltransferase2 and risk of lung and colorectal cancer.

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    Mahasneh, Amjad; Jubaili, Amal; El Bateiha, Ahmed; Al-Ghazo, Mohammad; Matalka, Ismail; Malkawi, Mousa

    2012-12-01

    The arylamine N-acetyltransferase 2 (NAT2) enzymes detoxify a wide range of naturally occurring xenobiotics including carcinogens and drugs. Point mutations in the NAT2 gene result in the variant alleles M1 (NAT2 *5A), M2 (NAT2*6A), M3 (NAT2*7) and M4 (NAT2 *14A) from the wild-type WT (NAT2 *4) allele. The current study was aimed at screening genetic polymorphisms of NAT2 gene in 49 lung cancer patients, 54 colorectal cancer patients and 99 cancer-free controls, using PCR-RFLP. There were significant differences in allele frequencies between lung cancer patients and controls in the WT, M2 and M3 alleles (p < 0.05). However, only M2 and M3 allele frequencies were different between colorectal cancer patients and controls (p < 0.05). There was a marginal significant difference in the distribution of rapid and slow acetylator genotypes between lung cancer patients and controls (p = 0.06 and p = 0.05, respectively), but not between colorectal cancer patients and controls (p = 1.0 and p = 0.95, respectively). Risk of lung cancer development was found to be lower in slow acetylators [odds ratio (OR): 0.51, 95% confidence interval (95% CI): 0.25, 1.02, p-value = 0.07]. No effect was observed in case of colorectal cancer. Our results showed that NAT2 genotypes and phenotypes might be involved in lung cancer but not colorectal cancer susceptibility in Jordan.

  15. Polymorphisms of arylamine N-acetyltransferase2 and risk of lung and colorectal cancer

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    Amjad Mahasneh

    2012-01-01

    Full Text Available The arylamine N-acetyltransferase 2 (NAT2 enzymes detoxify a wide range of naturally occurring xenobiotics including carcinogens and drugs. Point mutations in the NAT2 gene result in the variant alleles M1 (NAT2 *5A, M2 (NAT2*6A, M3 (NAT2*7 and M4 (NAT2 *14A from the wild-type WT (NAT2 *4 allele. The current study was aimed at screening genetic polymorphisms of NAT2 gene in 49 lung cancer patients, 54 colorectal cancer patients and 99 cancer-free controls, using PCR-RFLP. There were significant differences in allele frequencies between lung cancer patients and controls in the WT, M2 and M3 alleles (p < 0.05. However, only M2 and M3 allele frequencies were different between colorectal cancer patients and controls (p < 0.05. There was a marginal significant difference in the distribution of rapid and slow acetylator genotypes between lung cancer patients and controls (p = 0.06 and p = 0.05, respectively, but not between colorectal cancer patients and controls (p = 1.0 and p = 0.95, respectively. Risk of lung cancer development was found to be lower in slow acetylators [odds ratio (OR: 0.51, 95% confidence interval (95% CI: 0.25, 1.02, p-value = 0.07]. No effect was observed in case of colorectal cancer. Our results showed that NAT2 genotypes and phenotypes might be involved in lung cancer but not colorectal cancer susceptibility in Jordan.

  16. The Bacillus anthracis arylamine N-acetyltransferase ((BACAN)NAT1) that inactivates sulfamethoxazole, reveals unusual structural features compared with the other NAT isoenzymes

    DEFF Research Database (Denmark)

    Pluvinage, Benjamin; Li de la Sierra-Gallay, Inés; Kubiak, Xavier Jean Philippe

    2011-01-01

    Arylamine N-acetyltransferases (NATs) are xenobiotic-metabolizing enzymes that biotransform arylamine drugs. The Bacillus anthracis (BACAN)NAT1 enzyme affords increased resistance to the antibiotic sulfamethoxazole through its acetylation. We report the structure of (BACAN)NAT1. Unexpectedly...... marked differences in the mode of binding and location of coenzymeA when compared to the other NATs. This suggests that the mechanisms of cofactor recognition by NATs is more diverse than expected and supports the cofactor-binding site as being a unique subsite to target in drug design against bacterial...

  17. Small molecule inhibition of arylamine N-acetyltransferase Type I inhibits proliferation and invasiveness of MDA-MB-231 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tiang, Jacky M. [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia); Butcher, Neville J., E-mail: n.butcher@uq.edu.au [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia); Minchin, Rodney F. [School of Biomedical Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia)

    2010-02-26

    Arylamine N-acetyltransferase 1 is a phase II metabolizing enzyme that has been associated with certain breast cancer subtypes. While it has been linked to breast cancer risk because of its role in the metabolic activation and detoxification of carcinogens, recent studies have suggested it may be important in cell growth and survival. To address the possible importance of NAT1 in breast cancer, we have used a novel small molecule inhibitor (Rhod-o-hp) of the enzyme to examine growth and invasion of the breast adenocarcinoma line MDA-MB-231. The inhibitor significantly reduced cell growth by increasing the percent of cells in G2/M phase of the cell cycle. Rhod-o-hp also reduced the ability of the MDA-MB-231 cells to grow in soft agar. Using an in vitro invasion assay, the inhibitor significantly reduced the invasiveness of the cells. To test whether this effect was due to inhibition of NAT1, the enzyme was knocked down using a lentivirus-based shRNA approach and invasion potential was significantly reduced. Taken together, the results of this study demonstrate that NAT1 activity may be important in breast cancer growth and metastasis. The study suggests that NAT1 is a novel target for breast cancer treatment.

  18. Effects of human arylamine N-acetyltransferase I knockdown in triple-negative breast cancer cell lines.

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    Tiang, Jacky M; Butcher, Neville J; Minchin, Rodney F

    2015-04-01

    Expression of human arylamine N-acetyltransferase I (NAT1) has been associated with various cancer subtypes and inhibition of this enzyme with small molecule inhibitors or siRNA affects cell growth and survival. Here, we have investigated the role of NAT1 in the invasiveness of breast cancer cells both in vitro and in vivo. We knocked down NAT1 using a lentivirus-based shRNA approach and observed marked changes in cell morphology in the triple-negative breast cancer cell lines MDA-MB-231, MDA-MB-436, and BT-549. Most notable was a reduction in the number and size of the filopodia protrusions on the surface of the cells. The loss of filopodia could be rescued by the reintroduction of NAT1 into the knockdown cells. NAT1 expression was localized to the lamellipodia and extended into the filopodia protrusions. In vitro invasion through Geltrex was significantly inhibited in both the MDA cell lines but not in the BT-549 cells. The expression of Snail increased when NAT1 was knocked down, while other genes associated with mesenchymal to epithelial transition (vimentin, cytokeratin-18, and Twist) did not show any changes. By contrast, both N-cadherin and β-catenin were significantly reduced. When MDA-MB-231 cells expressing shRNA were injected in vivo into BALB/c nu/nu nude mice, a significant reduction in the number of colonies that formed in the lungs was observed. Taken together, the results show that NAT1 can alter the invasion and metastatic properties of some triple-negative breast cancer cells but not all. The study suggests that NAT1 may be a novel therapeutic target in a subset of breast cancers.

  19. Acrolein, an α,β-unsaturated aldehyde, irreversibly inhibits the acetylation of aromatic amine xenobiotics by human arylamine N-acetyltransferase 1.

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    Bui, Linh C; Manaa, Amine; Xu, Ximing; Duval, Romain; Busi, Florent; Dupret, Jean-Marie; Rodrigues-Lima, Fernando; Dairou, Julien

    2013-07-01

    Acrolein is an electrophilic α,β-unsaturated aldehyde of industrial, pharmaceutic, and toxicologic importance to which we are exposed in environmental, occupational, and therapeutic situations. Acrolein is known to exert different biologic effects through reactions with cellular macromolecules such as DNA, certain proteins, or glutathione. In many situations (such as in tobacco smoke or other fumes), exposure to acrolein occurs concomitantly with other compounds such as aromatic amine chemicals. Interestingly, it has been shown that acrolein could impact the cellular metabolism of aromatic xenobiotics through an indirect mechanism based on the transcriptional induction of phase II xenobiotic-metabolizing enzymes. Here we report a novel mechanism by which acrolein acts on the metabolism of aromatic foreign chemicals. We provide molecular, kinetic, and cellular evidence that acrolein can react directly and irreversibly with arylamine N-acetyltransferases, a major family of xenobiotic-metabolizing enzymes involved in the metabolization of aromatic amine chemicals. Formation of an acrolein adduct with a catalytic cysteine residue in the active site is responsible for the impairment of aromatic amine acetylation by the enzyme. This biochemical process may represent an additional mechanism by which acrolein impacts the metabolism and fate of aromatic amine drugs and pollutants.

  20. Polymorphisms in the Human Cytochrome P450 and Arylamine N-Acetyltransferase: Susceptibility to Head and Neck Cancers

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    Rim Khlifi

    2013-01-01

    Full Text Available The occurrence of head and neck cancer (HNC is associated with smoking and alcohol drinking. Tobacco smoking exposes smokers to a series of carcinogenic chemicals. Cytochrome P450 enzymes (CYP450s, such as CYP1A1, CYP1B1, and CYP2D6, usually metabolize carcinogens to their inactive derivatives, but they occasionally convert the chemicals to more potent carcinogens. In addition, via CYP450 (CYP2E1 oxidase, alcohol is metabolized to acetaldehyde, a highly toxic compound, which plays an important role in carcinogenesis. Furthermore, two N-acetyltransferase isozymes (NATs, NAT1 and NAT2, are polymorphic and catalyze both N-acetylation and O-acetylation of aromatic and heterocyclic amine carcinogens. Genetic polymorphisms are associated with a number of enzymes involved in the metabolism of carcinogens important in the induction of HNC. It has been suggested that such polymorphisms may be linked to cancer susceptibility. In this paper, we select four cytochrome P450 enzymes (CYP1A1, CYP1BA1, CYP2D6, and CYP2E1, and two N-acetyltransferase isozymes (NAT1 and NAT2 in order to summarize and analyze findings from the literature related to HNC risk by focusing on (i the interaction between these genes and the environment, (ii the impact of genetic defect on protein activity and/or expression, and (iii the eventual involvement of race in such associations.

  1. Identification of cancer chemopreventive isothiocyanates as direct inhibitors of the arylamine N-acetyltransferase-dependent acetylation and bioactivation of aromatic amine carcinogens

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    Duval, Romain; Xu, Ximing; Bui, Linh-Chi; Mathieu, Cécile; Petit, Emile; Cariou, Kevin; Dodd, Robert H.; Dupret, Jean-Marie; Rodrigues-Lima, Fernando

    2016-01-01

    Aromatic amines (AAs) are chemicals of industrial, pharmacological and environmental relevance. Certain AAs, such as 4-aminobiphenyl (4-ABP), are human carcinogens that require enzymatic metabolic activation to reactive chemicals to form genotoxic DNA adducts. Arylamine N-acetyltransferases (NAT) are xenobiotic metabolizing enzymes (XME) that play a major role in this carcinogenic bioactivation process. Isothiocyanates (ITCs), including benzyl-ITC (BITC) and phenethyl-ITC (PEITC), are phytochemicals known to have chemopreventive activity against several aromatic carcinogens. In particular, ITCs have been shown to modify the bioactivation and subsequent mutagenicity of carcinogenic AA chemicals such as 4-ABP. However, the molecular and biochemical mechanisms by which these phytochemicals may modulate AA carcinogens bioactivation and AA-DNA damage remains poorly understood. This manuscript provides evidence indicating that ITCs can decrease the metabolic activation of carcinogenic AAs via the irreversible inhibition of NAT enzymes and subsequent alteration of the acetylation of AAs. We demonstrate that BITC and PEITC react with NAT1 and inhibit readily its acetyltransferase activity (ki = 200 M−1.s−1 and 66 M−1.s−1 for BITC and PEITC, respectively). Chemical labeling, docking approaches and substrate protection assays indicated that inhibition of the acetylation of AAs by NAT1 was due to the chemical modification of the enzyme active site cysteine. Moreover, analyses of AAs acetylation and DNA adducts in cells showed that BITC was able to modulate the endogenous acetylation and bioactivation of 4-ABP. In conclusion, we show that direct inhibition of NAT enzymes may be an important mechanism by which ITCs exert their chemopreventive activity towards AA chemicals. PMID:26840026

  2. Interaction of wild type, G68R and L125M isoforms of the arylamine-N-acetyltransferase from Mycobacterium tuberculosis with isoniazid: a computational study on a new possible mechanism of resistance.

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    Ramos, Ricardo Martins; Perez, Janaína Menezes; Baptista, Luis André; de Amorim, Hermes Luís Neubauer

    2012-09-01

    Isoniazid (INH) is a front-line drug used in the treatment of tuberculosis (TB), a disease that remains a major cause of death worldwide. Isoniazid is a prodrug, requiring activation in the mycobacterial cell by the catalase-peroxidase (CP) enzyme. Recent studies have suggested that acetylation of INH by the arylamine-N-acetyltransferase from Mycobacterium tuberculosis (TBNAT) may be a possible cause of inactivation of the drug thus resulting in resistant strains. In this study, computational techniques were applied to investigate the binding of isoniazid to three TBNAT isoforms: wild type, G68R and L125M. Since there is no experimental structure available, molecular dynamics (MD) simulations were initially used for the refinement of TBNAT homology models. Distinct conformations of the models were selected during the production stage of MD simulations for molecular docking experiments with the drug. Finally, each mode of binding was refined by new molecular MD simulations. Essential dynamics (ED) analysis and linear interaction energy calculations (LIE) were used to evaluate the impact of amino acid substitutions on the structural and binding properties of the enzymes. The results suggest that the wild type and the G68R TBNATs have a similar pattern of affinity to INH. On the other hand, the calculated enzyme-INH dissociation constant (KD) was estimated 33 times lower for L125M isoform in comparison with wild type enzyme. This last finding is consistent with the hypothesis that isolated mutations in the tbnat gene can produce M. tuberculosis strains resistant to isoniazid.

  3. 5-methyl-tetrahydrofolate and the S-adenosylmethionine cycle in C57BL/6J mouse tissues: gender differences and effects of arylamine N-acetyltransferase-1 deletion.

    Directory of Open Access Journals (Sweden)

    Katey L Witham

    Full Text Available Folate catabolism involves cleavage of the C(9-N(10 bond to form p-aminobenzoylgluamate (PABG and pterin. PABG is then acetylated by human arylamine N-acetyltransferase 1 (NAT1 before excretion in the urine. Mice null for the murine NAT1 homolog (Nat2 show several phenotypes consistent with altered folate homeostasis. However, the exact role of Nat2 in the folate pathway in vivo has not been reported. Here, we examined the effects of Nat2 deletion in male and female mice on the tissue levels of 5-methyl-tetrahydrofolate and the methionine-S-adenosylmethionine cycle. We found significant gender differences in hepatic and renal homocysteine, S-adenosylmethionine and methionine levels consistent with a more active methionine-S-adenosylmethionine cycle in female tissues. In addition, methionine levels were significantly higher in female liver and kidney. PABG was higher in female liver tissue but lower in kidney compared to male tissues. In addition, qPCR of mRNA extracted from liver tissue suggested a significantly lower level of Nat2 expression in female animals. Deletion of Nat2 affected liver 5- methyl-tetrahydrofolate in female mice but had little effect on other components of the methionine-S-adenosylmethionine cycle. No N-acetyl-PABG was observed in any tissues in Nat2 null mice, consistent with the role of Nat2 in PABG acetylation. Surprisingly, tissue PABG levels were similar between wild type and Nat2 null mice. These results show that Nat2 is not required to maintain tissue PABG homeostasis in vivo under normal conditions.

  4. Molecular Dynamics and Combined QM/MM Studies on the Deactivation of anti-Tubercular Drug Isoniazid by Arylamine N-Acetyltransferases

    Institute of Scientific and Technical Information of China (English)

    乔青安; 马翠华; 宋慧玲; 蔡红兰; 蔡政亭; 冯大诚

    2012-01-01

    Both a molecule dynamic study and a combined quantum mechanics and mole-cule mechanics(QM/MM) study on the acetylating deactivation mechanism of isoniazid were presented.This type of reaction was catalyzed by arylamine N-acetyltransferases(NATs) and the results strongly support a direct acetyl group transfer process rather than a stepwise one.The isoniazid was strictly restrained in proper relative position to accept the acetyl group by a Hydrogen-bond network formed by the residues at the active center.The residues,His110 and Cys70,would be functioned as 'general base' rather than 'general acid'.If all the residues(including H2O molecules) were removed from the system,the activation energy will be increased from 145.1 to 243.3 kJ/mol.The calculations met the experimental data with good agreement.

  5. Benzodiazepines: rat pinealocyte binding sites and augmentation of norepinephrine-stimulated N-acetyltransferase activity

    Energy Technology Data Exchange (ETDEWEB)

    Matthew, E.; Parfitt, A.G.; Sugden, D.; Engelhardt, D.L.; Zimmerman, E.A.; Klein, D.C.

    1984-02-01

    Studies of (/sup 3/H)diazepam binding to intact rat pineal cells were carried out in tissue culture preparations. The binding was saturable, reversible and proportional to the number of cells used. Scatchard analysis resulted in a linear plot (Kd . 23 nM, maximum binding sites (Bmax) . 1.56 pmol/mg of protein for cells in monolayer culture; Kd . 7 nM, Bmax . 1.3 pmol/mg of protein for cells in suspension culture). Inhibition constants (Ki) for clonazepam (500 nM), flunitrazepam (38 nM) and Ro-5-4864 (5 nM) indicated that the binding sites were probably of the ''peripheral'' type. In addition, the effects of diazepam on norepinephrine-stimulated N-acetyltransferase (NAT) activity were studied in organ culture and dissociated cell culture. Diazepam (10-50 microM) both prolonged and increased the magnitude of the norepinephrine-induced increase in NAT activity but did not affect the initial rate of rise of enzyme activity. The effect was dose-dependent and was also seen with clonazepam, flunitrazepam and Ro-5-4864, but not with Ro-15-1788. Diazepam, by itself, at these concentrations, had no effect on NAT, but enzyme activity was increased by higher concentrations (0.1-1 mM). Although a relationship between the (/sup 3/H)diazepam binding sites described here and the effect of benzodiazepines on NAT cannot be established from these studies, the data suggest that the benzodiazepines may alter melatonin levels through their action on NAT.

  6. Differential regulation of arylalkylamine N-acetyltransferase activity in chicken retinal ganglion cells by light and circadian clock.

    Science.gov (United States)

    Valdez, Diego J; Garbarino-Pico, Eduardo; Díaz, Nicolás M; Silvestre, David C; Guido, Mario E

    2012-10-01

    Retinal ganglion cells (RGCs) contain circadian clocks driving melatonin synthesis during the day, a subset of these cells acting as nonvisual photoreceptors sending photic information to the brain. In this work, the authors investigated the temporal and light regulation of arylalkylamine N-acetyltransferase (AA-NAT) activity, a key enzyme in melatonin synthesis. The authors first examined this activity in RGCs of wild-type chickens and compared it to that in photoreceptor cells (PRs) from animals maintained for 48 h in constant dark (DD), light (LL), or regular 12-h:12-h light-dark (LD) cycle. AA-NAT activity in RGCs displayed circadian rhythmicity, with highest levels during the subjective day in both DD and LL as well as in the light phase of the LD cycle. In contrast, AA-NAT activity in PRs exhibited the typical nocturnal peak in DD and LD, but no detectable oscillation was observed under LL, under which conditions the levels were basal at all times examined. A light pulse of 30-60 min significantly decreased AA-NAT activity in PRs during the subjective night, but had no effect on RGCs during the day or night. Intraocular injection of dopamine (50 nmol/eye) during the night to mimic the effect of light presented significant inhibition of AA-NAT activity in PRs compared to controls but had no effect on RGCs. The results clearly demonstrate that the regulation of the diurnal increase in AA-NAT activity in RGCs of chickens undergoes a different control mechanism from that observed in PRs, in which the endogenous clock, light, and dopamine exhibited differential effects.

  7. Insight into cofactor recognition in arylamine N-acetyltransferase enzymes

    DEFF Research Database (Denmark)

    Xu, Ximing; Li de la Sierra-Gallay, Inés; Kubiak, Xavier Jean Philippe;

    2015-01-01

    for Bacillus anthracis NAT1 and Homo sapiens NAT2. Therefore, in contrast to previous data, this study shows that different orthologous NATs can bind their cofactors in a similar way, suggesting that the mode of binding CoA in this family of enzymes is less diverse than previously thought. Moreover...

  8. Occurrence, uses, and carcinogenicity of arylamines.

    Science.gov (United States)

    Chung, King-Thom

    2015-01-01

    Arylamines are chemically synthesized and contained in oxidants, epoxy polymers, explosives, fungicides, pesticides, colorants, polyurethanes, and used in rubber, pharmacology, cosmetics, and other chemical industries. Many arylamines are ubiquitously present in cigarette smoke, cooking fume hoods, foods, automobile exhaust, industrial sites, etc. Some arylamines can be generated through azo reduction by intestinal, skin, and environmental microorganisms from azo dyes that are widely used. Arylamines can also be generated by reduction of the nitro-group containing polyhydrated hydrocarbons including muntions. Some arylamines are released by burning nitrogen containing organic materials at high temperatures. Some medical drugs are also arylamines. Furthermore, many arylamines are essential constituents of normal metabolism or the result of abnormal metabolism or dietary sources. Some arylamines are mutagenic, carcinogenic or the cause of other kinds of maladies. Some arylamine are considered the major etiological agents of bladder tumors in humans and animals but may also induce other types of cancers in various organs. The organ, tissue, and species specificity of the arylamine-inducing carcinogenesis may be determined by their availability, distribution, and the presence of metabolic activation/detoxicification enzymes of each organ or tissue of different species. The ubiquitous arylamines, therefore, pose serious hazards to human health and environment. This article will address the occurrence, uses, carcinogenicity, and other arylamines-induced diseases.

  9. Urinary acetylated metabolites and N-acetyltransferase-2 genotype in human subjects treated with a para-phenylenediamine-containing oxidative hair dye

    NARCIS (Netherlands)

    Nohynek, G.J.; Skare, J.A.; Meuling, W.J.A.; Hein, D.W.; Bie, A.T.H.J. de; Toutain, H.

    2004-01-01

    In the organism of mammals, important detoxification pathways of arylamines are catalysed by N-acetyltransferase 2 (NAT2). A recent case-control epidemiology study suggested that human NAT2 slow acetylators exposed to oxidative hair dyes may be at greater risk to develop bladder cancer. We therefore

  10. Refinement of the prediction of N-acetyltransferase 2 (NAT2) phenotypes with respect to enzyme activity and urinary bladder cancer risk.

    Science.gov (United States)

    Selinski, Silvia; Blaszkewicz, Meinolf; Ickstadt, Katja; Hengstler, Jan G; Golka, Klaus

    2013-12-01

    Polymorphisms of N-acetyltransferase 2 (NAT2) are well known to modify urinary bladder cancer risk as well as efficacy and toxicity of pharmaceuticals via reduction in the enzyme's acetylation capacity. Nevertheless, the discussion about optimal NAT2 phenotype prediction, particularly differentiation between different degrees of slow acetylation, is still controversial. Therefore, we investigated the impact of single nucleotide polymorphisms and their haplotypes on slow acetylation in vivo and on bladder cancer risk. For this purpose, we used a study cohort of 1,712 bladder cancer cases and 2,020 controls genotyped for NAT2 by RFLP-PCR and for the tagSNP rs1495741 by TaqMan(®) assay. A subgroup of 344 individuals was phenotyped by the caffeine test in vivo. We identified an 'ultra-slow' acetylator phenotype based on combined *6A/*6A, *6A/*7B and *7B/*7B genotypes containing the homozygous minor alleles of C282T (rs1041983, *6A, *7B) and G590A (rs1799930, *6A). 'Ultra-slow' acetylators have significantly about 32 and 46 % lower activities of caffeine metabolism compared with other slow acetylators and with the *5B/*5B genotypes, respectively (P < 0.01, both). The 'ultra-slow' genotype showed an association with bladder cancer risk in the univariate analysis (OR = 1.31, P = 0.012) and a trend adjusted for age, gender and smoking habits (OR = 1.22, P = 0.082). In contrast, slow acetylators in general were not associated with bladder cancer risk, neither in the univariate (OR = 1.02, P = 0.78) nor in the adjusted (OR = 0.98, P = 0.77) analysis. In conclusion, this study suggests that NAT2 phenotype prediction should be refined by consideration of an 'ultra-slow' acetylation genotype.

  11. Opposite effects of EGTA and neutral surfactants on the loss of chicken pineal serotonin N-acetyltransferase activity.

    Science.gov (United States)

    Rodriguez-Cabello, J C; Arpa, F; Agapito, M T; Recio, J M

    1990-01-01

    The effects of some general purpose drugs on the deactivation and activity measurement of the chicken pineal gland enzyme serotonin N-acetyl transferase (EC 2.3.1.5.) were studied. The drugs used were EGTA and two neutral surfactants, Nonidet P40 and Triton X-100. Enzyme activity showed significant variations ranging from 2.8 +/- 1.3 nmol/gland/h when Nonidet P40 was added to the homogenate buffer, to 31.8 +/- 1.7 nmol/gland/h when EGTA was present. This striking variation seemed to be caused by the ability of these compounds to modify the rate of NAT deactivation acting either as accelerating agents, as in the case of the detergents or as braking agent, as in the case of EGTA.

  12. Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT; a key enzyme for physiological and behavioral switch in arthropods

    Directory of Open Access Journals (Sweden)

    Susumu eHiragaki

    2015-04-01

    Full Text Available The evolution of N-acetyltransfeases (NATs seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT has been extensively studied since it Leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT, and also xenobiotic reactions (arylamine NAT or simply NAT. NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO activity is limited in insects, but NAT-mediated degradation prevails. However, unexpectedly iaaNAT occurs not only among arthropods but also among basal deuterostomia, and is therefore more apomorphic. Our analyses illustrate that iaaNATs has unique physiological roles but at the same time it plays a role in a timezyme function, at least in photoperiodism. Photoperiodism has been considered as a function of circadian system but the detailed molecular mechanism is not well understood. We propose a molecular hypothesis for photoperiodism in Antheraea pernyi based on the transcription regulation of NAT interlocked by the

  13. In vitro effects of steroid hormones on arylalkylamine N-acetyltransferase (AA-NAT) activity in the pineal of fish, Clarias gariepinus (Burchell, 1822) during different phases of breeding cycle.

    Science.gov (United States)

    Yanthan, L; Gupta, B B P

    2007-08-01

    In vitro effects of gonadal hormones (testosterone, 17beta-estradiol estriol and estrone) and corticosteroid hormones (corticosterone and cortisol) were studied on arylalklyamine N-acetyltransferase (AA-NAT) activity in the pineal organ of the fish, C. gariepinus during quiescent, progressive, breeding and regressive phases of its annual breeding cycle. The pineals were collected under dim red light, maintained in organ culture for 7 hr and incubated with three concentrations (10(-6), 10(-5) and 10(-4) M) of hormones for 6 hr. The treatments with gonadal hormones and corticosteroid hormones inhibited pineal AA-NAT activity in a dose-dependent manner during all the phases of the breeding cycle. AA-NAT activity was comparatively more sensitive to the inhibitory effects of the gonadal hormones during the regressive phase and less sensitive during the quiescent phase. Further, the enzyme activity was more sensitive to the inhibitory effects of corticosteroid hormones (corticosterone and cortisol) during the breeding phase and less sensitive during the quiescent phase. These findings seem to suggest that gonadal hormones and corticosteroid hormones have direct inhibitory influence on AA-NAT activity and, hence melatonin synthesis in the photoreceptive pineal organ of C. gariepinus.

  14. Effects of single nucleotide polymorphisms on human N-acetyltransferase 2 structure and dynamics by molecular dynamics simulation.

    Directory of Open Access Journals (Sweden)

    M Rajasekaran

    Full Text Available BACKGROUND: Arylamine N-acetyltransferase 2 (NAT2 is an important catalytic enzyme that metabolizes the carcinogenic arylamines, hydrazine drugs and chemicals. This enzyme is highly polymorphic in different human populations. Several polymorphisms of NAT2, including the single amino acid substitutions R64Q, I114T, D122N, L137F, Q145P, R197Q, and G286E, are classified as slow acetylators, whereas the wild-type NAT2 is classified as a fast acetylator. The slow acetylators are often associated with drug toxicity and efficacy as well as cancer susceptibility. The biological functions of these 7 mutations have previously been characterized, but the structural basis behind the reduced catalytic activity and reduced protein level is not clear. METHODOLOGY/PRINCIPAL FINDINGS: We performed multiple molecular dynamics simulations of these mutants as well as NAT2 to investigate the structural and dynamical effects throughout the protein structure, specifically the catalytic triad, cofactor binding site, and the substrate binding pocket. None of these mutations induced unfolding; instead, their effects were confined to the inter-domain, domain 3 and 17-residue insert region, where the flexibility was significantly reduced relative to the wild-type. Structural effects of these mutations propagate through space and cause a change in catalytic triad conformation, cofactor binding site, substrate binding pocket size/shape and electrostatic potential. CONCLUSIONS/SIGNIFICANCE: Our results showed that the dynamical properties of all the mutant structures, especially in inter-domain, domain 3 and 17-residue insert region were affected in the same manner. Similarly, the electrostatic potential of all the mutants were altered and also the functionally important regions such as catalytic triad, cofactor binding site, and substrate binding pocket adopted different orientation and/or conformation relative to the wild-type that may affect the functions of the mutants

  15. Characterization of N-acetyltransferase 1 and 2 polymorphisms and haplotype analysis for inflammatory bowel disease and sporadic colorectal carcinoma

    Directory of Open Access Journals (Sweden)

    Cobbs Gary A

    2007-05-01

    Full Text Available Abstract Background N-acetyltransferase 1 (NAT1 and 2 (NAT2 are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD consist of Crohn's disease (CD and ulcerative colitis (UC, both are associated with increased colorectal cancer (CRC risk. We hypothesized that NAT1 and/or NAT2 polymorphisms contribute to the increased cancer evident in IBD. Methods A case control study was performed with 729 Caucasian participants, 123 CRC, 201 CD, 167 UC, 15 IBD dysplasia/cancer and 223 controls. NAT1 and NAT2 genotyping were performed using Taqman based techniques. Eight single nucleotide polymorphisms (SNPs were characterized for NAT1 and 7 SNPs for NAT2. Haplotype frequencies were estimated using an Expectation-Maximization (EM method. Disease groups were compared to a control group for the frequencies at each individual SNP separately. The same groups were compared for the frequencies of NAT1 and NAT2 haplotypes and deduced NAT2 phenotypes. Results No statistically significant differences were found for any comparison. Strong linkage disequilibrium was present among both the NAT1 SNPs and the NAT2 SNPs. Conclusion This study did not demonstrate an association between NAT1 and NAT2 polymorphisms and IBD or sporadic CRC, although power calculations indicate this study had sufficient sample size to detect differences in frequency as small as 0.05 to 0.15 depending on SNP or haplotype.

  16. Structure and Active Stie Residues of Pg1D, an N-Acetyltransferase from the Bacillosamine Synthetic Pathway Required for N-Glycan Synthesis in Campylobacter jejuni

    Energy Technology Data Exchange (ETDEWEB)

    Rangarajan,E.; Ruane, K.; Sulea, T.; Watson, D.; Proteau, A.; Leclerc, S.; Cygler, M.; Matte, A.; Young, N.

    2008-01-01

    Campylobacter jejuni is highly unusual among bacteria in forming N-linked glycoproteins. The heptasaccharide produced by its pgl system is attached to protein Asn through its terminal 2, 4-diacetamido-2, 4,6-trideoxy-d-Glc (QuiNAc4NAc or N, N'-diacetylbacillosamine) moiety. The crucial, last part of this sugar's synthesis is the acetylation of UDP-2-acetamido-4-amino-2, 4,6-trideoxy-d-Glc by the enzyme PglD, with acetyl-CoA as a cosubstrate. We have determined the crystal structures of PglD in CoA-bound and unbound forms, refined to 1.8 and 1.75 Angstroms resolution, respectively. PglD is a trimer of subunits each comprised of two domains, an N-terminal {alpha}/{beta}-domain and a C-terminal left-handed {beta}-helix. Few structural differences accompany CoA binding, except in the C-terminal region following the {beta}-helix (residues 189-195), which adopts an extended structure in the unbound form and folds to extend the {beta}-helix upon binding CoA. Computational molecular docking suggests a different mode of nucleotide-sugar binding with respect to the acetyl-CoA donor, with the molecules arranged in an 'L-shape', compared with the 'in-line' orientation in related enzymes. Modeling indicates that the oxyanion intermediate would be stabilized by the NH group of Gly143', with His125' the most likely residue to function as a general base, removing H+ from the amino group prior to nucleophilic attack at the carbonyl carbon of acetyl-CoA. Site-specific mutations of active site residues confirmed the importance of His125', Glu124', and Asn118. We conclude that Asn118 exerts its function by stabilizing the intricate hydrogen bonding network within the active site and that Glu124' may function to increase the pKa of the putative general base, His125'.

  17. Active cigarette smoking and the risk of breast cancer at the level of N-acetyltransferase 2 (NAT2) gene polymorphisms.

    Science.gov (United States)

    Kasajova, Petra; Holubekova, Veronika; Mendelova, Andrea; Lasabova, Zora; Zubor, Pavol; Kudela, Erik; Biskupska-Bodova, Kristina; Danko, Jan

    2016-06-01

    The aim of our study was to assess the correlation between the tobacco exposure and NAT2 gene (rs1041983 C/T, rs1801280 T/C, rs1799930 G/A) polymorphisms in association with breast cancer development. We wanted to determine the prognostic clinical importance of these polymorphisms in association with smoking and breast cancer. For the detection of possible association between smoking, NAT2 gene polymorphisms, and the risk of breast cancer, we designed a case-controlled study with 198 patients enrolled, 98 breast cancer patients and 100 healthy controls. Ten milliliters of peripheral blood from the cubital vein was withdrawn from every patient. The HRM (high resolution melting) analysis was used for the detection of three abovementioned NAT2 gene polymorphisms. When comparing a group of women smoking more than 5 cigarettes a day with the patients smoking fewer than 5 cigarettes a day, we found out that if women were the carriers of aberrant AA genotype for rs1799930, the first group of women had higher risk of breast carcinoma than the second group. If patients were the carriers of aberrant TT genotype for rs1041983, for rs1801280CC genotype, and rs1799930AA genotype and they smoked more than 5 cigarettes a day, they had higher risk of malignant breast disease than never-smoking women. Our results confirm the hypothesis that NAT2 gene polymorphisms (rs1041983 C/T, rs1801280 T/C, and rs1799930 G/A) in association with long-period active smoking could be the possible individual risk-predicting factors for breast cancer development in the population of Slovak women.

  18. Structural and functional characterization of an arylamine N-acetyltransferase from the pathogen Mycobacterium abscessus

    DEFF Research Database (Denmark)

    Cocaign, Angélique; Kubiak, Xavier Jean Philippe; Xu, Ximing;

    2014-01-01

    -modifying enzyme from M. abscessus and provides bases to better understand the substrate/inhibitor-binding specificities among mycobacterial NATs and to identify/optimize specific inhibitors. These data should also contribute to the understanding of the mechanisms that are responsible for the pathogenicity...

  19. N-Acetyltransferase 1 Polymorphism and Breast Cancer Risk

    Science.gov (United States)

    2011-10-01

    analysis of the N-acetyltransferase 1 gene (NAT1*) using polymerase chain reaction-restriction fragment- single strand conformation polymorphism assay...risk of smoking-induced lung cancer (Bouchardy et al., 1998). NAT1*14B is characterized by a single nucleotide polymorphism (SNP) G560A (rs4986782...Structure-function analyses of single nucleotide polymorphisms in human N-acetyltransferase 1. Drug Metab Rev 40, 169-184. Zheng, W., Deitz, A.C., Campbell

  20. Metabolic activation of three arylamines and two organophosphorus insecticides by coriander (Coriandrum sativum) a common edible vegetable.

    Science.gov (United States)

    Cortés-Eslava, J; Gómez-Arroyo, S; Villalobos-Pietrini, R; Espinosa-Aguirre, J J

    2001-12-15

    Organophosphorus insecticides and arylamines, widely distributed in the environment, can be activated into mutagens by plants. Plant activation of three aromatic amines, 4-nitro-o-phenylenediamine (NOP), m-phenylenediamine (m-PDA) and 2-aminofluorene (2AF), and two organophosphorus insecticides, dimethoate and methyl parathion has been the focus of this study. The plant cell/microbe coincubation assay was used employing coriander (Coriandrum sativum) suspended cell cultures as the activating system. Interestingly, this vegetable is included in the Mexican diet and ingested generally uncooked and could have epidemiological consequences. As a genetic end point, the Salmonella typhimurium tester strain TA98 was used. Protein contents, as well as peroxidase activity and peroxidase activity inhibited by diethyldithiocarbamate (DEDTC) of coriander cultures were determined after the coculture. Coriander cells highly activated three aromatic amines, NOP, m-PDA and 2-AF to mutagenic products detected in Salmonella. On the other hand, insecticides were only lightly activated, probably because peroxidase activity of coriander cells was inhibited, corroborated by DEDTC peroxidase inhibition. In all the assays, NOP was the more potent mutagenic compound. The results demonstrated that coriander cells were metabolically competent and suitable for a plant cell microbe coincubation assay, developed to analyze the promutagen activation by plant systems and can be used as a indicator of potential genetic effects.

  1. Metabolic activation of N-hydroxy arylamines, N-hydroxy heterocyclic amines and ring-hydroxymethyl polycyclic aromatic hydrocarbons by human sulfotransferases

    Energy Technology Data Exchange (ETDEWEB)

    Chou, H.C.

    1993-01-01

    Arylamines and polycyclic aromatic hydrocarbons (PAHs) are two major classes of chemical carcinogens. N-Hydroxylation of arylamines is regarded to be a necessary process for their mutagenicity and carcinogenicity, while alkyl-hydroxylation is the major metabolic pathway for alkyl-substituted PAHs. Evidence has been presented that sulfation of several N-hydroxy arylamines and hydroxymethyl PAHs is an important pathway leading to the formation of ultimate carcinogens in experiment animals. Sulfation of these chemicals forms putative sulfuric acid ester intermediates that can rearrange to electrophilic nitrenium or carbenium ions capable of forming covalent adducts with important cellular macromolecules. In order to study the metabolic activation by sulfotransferase(s) in various human tissue preparations an in vitro enzymatic assay was established. A metabolic phenotyping method was also developed for thermostable phenolsulfotransferase (TS-PST) in platelet homogenates (correlated with TS-PST activity in other tissues) based on a simple colorimetric assay using 2-naphthol as substrate. By using a PAPS-regenerating system to supply the activated sulfate and calf thymus DNA to trap the reactive metabolites, we found that N-hydroxy derivatives of the carcinogens, 4-aminobiphenyl (4-ABP), 4,4[prime]-methylene-bis(2-chloroaniline) (MOCA), 2-acetylaminofluorene (2-AAF), 2-aminofluorene (2-AF), 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP), and 2-amino-6-methyldipyrido [1,2-1:3[prime],2[prime]-d]imidazole (Glu-P-1) were metabolically activated by human TS-PST. On the other hand, three methyl-hydroxylated derivatives (7-OH, 12-OH, and 7,12-diOH) of 7, 12-dimethylbenz[a]anthracene (DMBA) were metabolically activated by human steroid sulfotransferase. Human sulfotransferase(s)-mediated activation of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) or 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) was not observed.

  2. Structural Studies on a Glucosamine/Glucosaminide N-Acetyltransferase.

    Science.gov (United States)

    Dopkins, Brandon J; Tipton, Peter A; Thoden, James B; Holden, Hazel M

    2016-08-16

    Glucosamine/glucosaminide N-acetyltransferase or GlmA catalyzes the transfer of an acetyl group from acetyl CoA to the primary amino group of glucosamine. The enzyme from Clostridium acetobutylicum is thought to be involved in cell wall rescue. In addition to glucosamine, GlmA has been shown to function on di- and trisaccharides of glucosamine as well. Here we present a structural and kinetic analysis of the enzyme. For this investigation, eight structures were determined to resolutions of 2.0 Å or better. The overall three-dimensional fold of GlmA places it into the tandem GNAT superfamily. Each subunit of the dimer folds into two distinct domains which exhibit high three-dimensional structural similarity. Whereas both domains bind acetyl CoA, it is the C-terminal domain that is catalytically competent. On the basis of the various structures determined in this investigation, two amino acid residues were targeted for further study: Asp 287 and Tyr 297. Although their positions in the active site suggested that they may play key roles in catalysis by functioning as active site bases and acids, respectively, this was not borne out by characterization of the D287N and Y297F variants. The kinetic properties revealed that both residues were important for substrate binding but had no critical roles as acid/base catalysts. Kinetic analyses also indicated that GlmA follows an ordered mechanism with acetyl CoA binding first followed by glucosamine. The product N-acetylglucosamine is then released prior to CoA. The investigation described herein provides significantly new information on enzymes belonging to the tandem GNAT superfamily.

  3. Genetic variants in microsomal epoxide hydrolase and N-acetyltransferase 2 in susceptibility of IBD in the Danish population

    DEFF Research Database (Denmark)

    Ernst, Anja; Andersen, Vibeke; Østergaard, Mette;

    induce or sustain an immune response. Changes in detoxification of substances that causes epithelial damage may confer susceptibility to IBD. Hence, polymorphic enzymes involved in the detoxification processes may be risk factors of IBD. Methods. The two biotransformation enzymes microsomal epoxide...... hydrolase and N-acetyltransferase 2 were genotyped using TaqMan based Real-Time PCR in 388 patients with Crohn's disease (CD), 565 patients with ulcerative colitis (UC) and 796 healthy Danish controls. Results. No association was found between low microsomal epoxide hydrolase activity or slow N......-acetyltransferase 2 acetylator status and IBD. An association between high activity of microsomal epoxide hydrolase and disease diagnosis before age 40 in CD with an OR of 2.2(1.1- 4.2) P=0.02) was found. No other phenotypic associations were found for the two enzymes and IBD, regarding age at onset, disease location...

  4. A new arylalkylamine N-acetyltransferase in silkworm (Bombyx mori) affects integument pigmentation.

    Science.gov (United States)

    Long, Yaohang; Li, Jiaorong; Zhao, Tianfu; Li, Guannan; Zhu, Yong

    2015-04-01

    Dopamine is a precursor for melanin synthesis. Arylalkylamine N-acetyltransferase (AANAT) is involved in the melatonin formation in insects because it could catalyze the transformation from dopamine to dopamine-N-acetyldopamine. In this study, we identified a new AANAT gene in the silkworm (Bombyx mori) and assessed its role in the silkworm. The cDNA of this gene encodes 233 amino acids that shares 57 % amino acid identity with the Bm-iAANAT protein. We thus refer to this gene as Bm-iAANAT2. To investigate the role of Bm-iAANAT2, we constructed a transgenic interference system using a 3xp3 promoter to suppress the expression of Bm-iAANAT2 in the silkworm. We observed that melanin deposition occurs in the head and integument in transgenic lines. To verify the melanism pattern, dopamine content and the enzyme activity of AANAT were determined by high-performance liquid chromatography (HPLC). We found that an increase in dopamine levels affects melanism patterns on the heads of transgenic B. mori. A reduction in the enzyme activity of AANAT leads to changes in dopamine levels. We analyzed the expression of the Bm-iAANAT2 genes by qPCR and found that the expression of Bm-iAANAT2 gene is significantly lower in transgenic lines. Our results lead us to conclude that Bm-iAANAT2 is a new arylalkylamine N-acetyltransferase gene in the silkworm and is involved in the metabolism of the dopamine to avoid the generation of melanin.

  5. Reconstruction of N-acetyltransferase 2 haplotypes using PHASE.

    Science.gov (United States)

    Golka, Klaus; Blaszkewicz, Meinolf; Samimi, Mirabutaleb; Bolt, Hermann M; Selinski, Silvia

    2008-04-01

    The genotyping of N-acetyltransferase 2 (NAT2) by PCR/RFLP methods yields in a considerable percentage ambiguous results. To resolve this methodical problem a statistical approach was applied. PHASE v2.1.1, a statistical program for haplotype reconstruction was used to estimate haplotype pairs from NAT2 genotyping data, obtained by the analysis of seven single nucleotide polymorphisms relevant for Caucasians. In 1,011 out of 2,921 (35%) subjects the haplotype pairs were clearcut by the PCR/RFLP data only. For the majority of the data the applied method resulted in a multiplicity (2-4) of possible haplotype pairs. Haplotype reconstruction using PHASE v2.1.1 cleared this ambiguity in all cases but one, where an alternative haplotype pair was considered with a probability of 0.029. The estimation of the NAT2 haplotype is important because the assignment of the NAT2 alleles *12A, *12B, *12C or *13 to the rapid or slow NAT2 genotype has been discussed controversially. A clear assignment is indispensable in surveys of human bladder cancer caused by aromatic amine exposures. In conclusion, PHASE v2.1.1 software allowed an unambiguous haplotype reconstruction in 2,920 of 2,921 cases (>99.9%).

  6. New di(hetero)aryl)ethers and Di(hetero)arylamines in the thieno[3,2-b]pyridine series: synthesis, growth inhibitory activity on tumor cell lines and non tumor cells, effects on cell cycle and on apoptosis

    OpenAIRE

    Queiroz, Maria João R. P.; Peixoto, Daniela; Ricardo C. Calhelha; Soares, Pedro; Santos,Tiago; Raquel T. Lima; Campos, Joana F.; Abreu, Rui M. V.; Isabel C. F. R. Ferreira; Vasconcelos, M. Helena

    2014-01-01

    The thienopyridine skeleton has been reported as having interesting biological activities namely antitumor[1,2] antiangiogenic.[3A] New fluorinated and methoxylated di(hetero)arylethers and di(hetero)arylamines were prepared functionalizing 7-position of the thieno[3,2-bJpyridine, using copper (C-O) or palladium (C-N) catalyzed couplings, respectively, of the 7-t>rolmo: thieno[3,2-bJpyridine (1) with ortho, meta and para fluoro or methoxy phenols and anilines.

  7. N-acetylglucosamine sensing by a GCN5-related N-acetyltransferase induces transcription via chromatin histone acetylation in fungi

    Science.gov (United States)

    Su, Chang; Lu, Yang; Liu, Haoping

    2016-01-01

    N-acetylglucosamine (GlcNAc) exists ubiquitously as a component of the surface on a wide range of cells, from bacteria to humans. Many fungi are able to utilize environmental GlcNAc to support growth and induce cellular development, a property important for their survival in various host niches. However, how the GlcNAc signal is sensed and subsequently transduced is largely unknown. Here, we identify a gene that is essential for GlcNAc signalling (NGS1) in Candida albicans, a commensal and pathogenic yeast of humans. Ngs1 can bind GlcNAc through the N-terminal β-N-acetylglucosaminidase homology domain. This binding activates N-acetyltransferase activity in the C-terminal GCN5-related N-acetyltransferase domain, which is required for GlcNAc-induced promoter histone acetylation and transcription. Ngs1 is targeted to the promoters of GlcNAc-inducible genes constitutively by the transcription factor Rep1. Ngs1 is conserved in diverse fungi that have GlcNAc catabolic genes. Thus, fungi use Ngs1 as a GlcNAc-sensor and transducer for GlcNAc-induced transcription. PMID:27694804

  8. Molecular Evolution of Multiple Arylalkylamine N-Acetyltransferase (AANAT in Fish

    Directory of Open Access Journals (Sweden)

    Bina Zilberman-Peled

    2011-05-01

    Full Text Available Arylalkylamine N-acetyltransferase (AANAT catalyzes the transfer of an acetyl group from acetyl coenzyme A (AcCoA to arylalkylamines, including indolethylamines and phenylethylamines. Multiple aanats are present in teleost fish as a result of whole genome and gene duplications. Fish aanat1a and aanat2 paralogs display different patterns of tissue expression and encode proteins with different substrate preference: AANAT1a is expressed in the retina, and acetylates both indolethylamines and phenylethylamines; while AANAT2 is expressed in the pineal gland, and preferentially acetylates indolethylamines. The two enzymes are therefore thought to serve different roles. Here, the molecular changes that led to their specialization were studied by investigating the structure-function relationships of AANATs in the gilthead seabream (sb, Sperus aurata. Acetylation activity of reciprocal mutated enzymes pointed to specific residues that contribute to substrate specificity of the enzymes. Inhibition tests followed by complementary analyses of the predicted three-dimensional models of the enzymes, suggested that both phenylethylamines and indolethylamines bind to the catalytic pocket of both enzymes. These results suggest that substrate selectivity of AANAT1a and AANAT2 is determined by the positioning of the substrate within the catalytic pocket, and its accessibility to catalysis. This illustrates the evolutionary process by which enzymes encoded by duplicated genes acquire different activities and play different biological roles.

  9. Crystal structure and functional characterization of a glucosamine-6-phosphate N-acetyltransferase from Arabidopsis thaliana.

    Science.gov (United States)

    Riegler, Heike; Herter, Thomas; Grishkovskaya, Irina; Lude, Anja; Ryngajllo, Malgorzata; Bolger, Marie E; Essigmann, Bernd; Usadel, Björn

    2012-04-15

    GlcNAc (N-acetylglucosamine) is an essential part of the glycan chain in N-linked glycoproteins. It is a building block for polysaccharides such as chitin, and several glucosaminoglycans and proteins can be O-GlcNAcylated. The deacetylated form, glucosamine, is an integral part of GPI (glycosylphosphatidylinositol) anchors. Both are incorporated into polymers by glycosyltransferases that utilize UDP-GlcNAc. This UDP-sugar is synthesized in a short pathway comprising four steps starting from fructose 6-phosphate. GNA (glucosamine-6-phosphate N-acetyltransferase) catalyses the second of these four reactions in the de novo synthesis in eukaryotes. A phylogenetic analysis revealed that only one GNA isoform can be found in most of the species investigated and that the most likely Arabidopsis candidate is encoded by the gene At5g15770 (AtGNA). qPCR (quantitative PCR) revealed the ubiquitous expression of AtGNA in all organs of Arabidopsis plants. Heterologous expression of AtGNA showed that it is highly active between pH 7 and 8 and at temperatures of 30-40°C. It showed Km values of 231 μM for glucosamine 6-phosphate and 33 μM for acetyl-CoA respectively and a catalytic efficiency comparable with that of other GNAs characterized. The solved crystal structure of AtGNA at a resolution of 1.5 Å (1 Å=0.1 nm) revealed a very high structural similarity to crystallized GNA proteins from Homo sapiens and Saccharomyces cerevisiae despite less well conserved protein sequence identity.

  10. Carcinogenicity, allergenicity, and lupus-inducibility of arylamines.

    Science.gov (United States)

    Chung, King-Thom

    2016-01-01

    Arylamines are widely used in food, drugs, and cosmetics as well as other industries. These chemicals are present ubiquitously in cigarette smoke, smoke emitted from cooking fume hoods as well as are generated by diverse industries. Arylamines can be generated by cleavage of azo dyes by intestinal and skin microbiota. Some arylamines are used as drugs while others are constituents of human metabolism. Many of the arylamines are mutagenic and carcinogenic. They are generally recognized as the major cause of human bladder cancer, but arylamines can induce cancers of other organs in humans and animals. Some arylamines are allergenic, causing lupus like syndrome, or other maladies. In view of their unbiquitious nature and the diseases they cause, arylamines are probably the most important chemicals causing health problems.

  11. Polymorphism of N-acetyltransferase 2 (NAT2) Gene Polymorphism in Shanghai population:Occupational and Non-occupational Bladder Cancer Patient Groups

    Institute of Scientific and Technical Information of China (English)

    QING-WEN MA; GUO-FANG LIN; JI-GANG CHEN; CUI-QING XIANG; WEI-CHAO GUO; KLAUS GOLKA; JIAN-HUA SHEN

    2004-01-01

    Arylamine N-acetyltransferases (NATs) are involved in the detoxification of aromatic amines and hydrazine. In order to explore the possible association of NAT2 polymorphism with bladder cancer risk in benzidine exposed or non-exposed Chinese individuals, healthy subjects, subjects with bladder cancer of a former benzidine exposed cohort in Shanghai dyestuff industry and a group of bladder cancer patients without known occupational exposure to aromatic amines were genotyped for NAT2 gene polymorphism. Methods NAT2 genotyping was performed with a set of RFLP procedures at seven major polymorphic loci of gene coding area: G191A, C282T, T341C, C481T, G590A, A803G and G857A. Results The wild allele NAT2 *4 was the most prevalent allele (59%) in healthy individuals. The alleles NAT2*6A and NAT2*7B were also frequently observed (21% and 17%, respectively). In contrast to Caucasians, the percentage of slow acetylators was lower (12% in Chinese vs. 58% in Caucasians, P<0.001). No relevant differences were observed for homogenous rapid, heterogeneous rapid/slow and homogeneous slow acetylation genotypes between the healthy subjects and both groups of bladder cancer patients. Conclusion The present work did not support the association of slow acetylating genotypes of NAT2 gene with elevated risk of bladder cancer in Chinese whereas it was documented as an important genetically determined risk factor in Caucasians. Different mechanisms might play a role in individual susceptibility to bladder cancer related with aromatic amine exposure in various races or ethnic groups.

  12. 龙葵碱对HepG2细胞NAT1酶活性及动力学影响的研究%Study on the Effect of Solanine on N-acetyltransferase 1 Activity in HepG2

    Institute of Scientific and Technical Information of China (English)

    高世勇; 苏怡君; 季宇彬

    2011-01-01

    目的 探讨龙葵碱诱导HepG2细胞凋亡的芳香胺Ⅳ-乙酰化转移酶(NAT)1的影响.方法 采用高效液相色谱法(HPLC),以对氨基笨甲酸(PABA)为底物,以PABA被NAT1乙酰化为乙酰对氨基苯甲酸(Ac-PABA)的量反应NAT1酶的活性.观察不同浓度、不同时间龙葵碱对完整HepG2细胞NAT1酶活性的影响;龙葵碱对HepG2细胞细胞质中NAT1酶活性的影响;通过改变底物PABA浓度,采用双倒数作图法,以底物PABA浓度的倒数(1/S)对NAT1反应速率的倒数(1/V)作直线,得出回归方程,计算K和.结果 在NAT1酶活性测定中,龙葵碱能显著降低HepG2完整细胞NAT1的活性;龙葵碱能够降低HepG2细胞质内NAT1的活性;随着作用时间的增加Ac-PABA生成的量逐渐增加,但在相同作用时间段龙葵碱能显著降低Ac-PABA生成的量.动力学研究表明,以PABA为底物,对于HepG2完整细胞,阴性对照组的K和V分别为(1.04 x 10±8.36×10-5)mmol·L、(1.64×10±9.57×10)nmol·10cells,龙葵碱组的K和K分别为(1.06×10±6.97×10)mmol·L和(1.48×10±4.28×10)nmol·10cells·h.对于HepG2细胞质,阴性对照组的K和V分别为(3.32×10±2.35×10)mmol·L、(2.60×10±6.79×10)nmol·h·mg pro,龙葵碱组的K和K分别为(3.35×10±1.66×10)mmol·L和(2.22x10±8.12×10)nmol·h·mg(Pro),经统计学处理表明,对于HepG2完整细胞和细胞质,阴性对照组和龙葵碱组的K没有差异,而V差异显著结论 龙葵碱是HepG2细胞NAT1酶的非竞争性抑制剂.龙葵碱通过作用于NAT1与PABA结合位点以外的其他位点抑制NAT1酶的活性而诱导HepG2细胞凋亡.%OBJECTIVE To explore the relationship between N-acetyltransferase 1 activity and apoptosis inducing by solanine in HepG2 cell. METHODS The speed of PABA acetylation reaction mediated by NAT1 was teken as the indicator of the activity of NAT1 in intact HepG2 cells and their cytoplasm. HPLC was employed to determine the concentration of AC-PABA, the effects of different concentrations of

  13. Structure-based molecular design for thermostabilization of N-acetyltransferase Mpr1 involved in a novel pathway of L-arginine synthesis in yeast.

    Science.gov (United States)

    Nasuno, Ryo; Hirase, Saeka; Norifune, Saki; Watanabe, Daisuke; Takagi, Hiroshi

    2016-02-01

    Previously, N-Acetyltransferase Mpr1 was suggested to be involved in a novel pathway of L-arginine biosynthesis in yeast. Our recent crystallographic analysis demonstrated that the overall structure of Mpr1 is a typical folding among proteins in the Gcn5-related N-acetyltransferase superfamily, and also provided clues to the design of mutations for improvement of the enzymatic functions. Here, we constructed new stable variants, Asn203Lys- and Asn203Arg-Mpr1, which exhibited 2.4-fold and 2.2-fold longer activity half-lives than wild-type Mpr1, respectively, by structure-based molecular design. The replacement of Asn203 with a basic amino acid was suggested to stabilize α-helix 2, which is important for the Mpr1 structure, probably by neutralizing its dipole. In addition, the combination of two amino acid substitutions at positions 65 and 203 in Mpr1, Phe65Leu, which was previously isolated by the screening from PCR random mutagenesis library of MPR1, and Asn203Lys or Asn203Arg, led to further stabilization of Mpr1. Our growth assay suggests that overexpression of the stable Mpr1 variants increase L-arginine synthesis in yeast cells. Our finding is the first report on the rational engineering of Mpr1 for thermostabilization and could be useful in the construction of new yeast strains with higher L-arginine synthetic activity and also improved fermentation ability.

  14. Melatonin production in Escherichia coli by dual expression of serotonin N-acetyltransferase and caffeic acid O-methyltransferase.

    Science.gov (United States)

    Byeon, Yeong; Back, Kyoungwhan

    2016-08-01

    Melatonin is a well-known bioactive molecule produced in animals and plants and a well-studied natural compound. Two enzymatic steps are required for the biosynthesis of melatonin from serotonin. First, serotonin N-acetyltransferase (SNAT) catalyzes serotonin to N-acetylserotonin (NAS) followed by the action of N-acetylserotonin O-methyltransferase (ASMT), resulting in the synthesis of O-methylated NAS, also known as melatonin. Attempts to document melatonin production in Escherichia coli have been unsuccessful to date due to either low enzyme activity or inactive ASMT expression. Here, we employed caffeic acid O-methyltransferase (COMT) instead of ASMT, as COMT is a multifunctional enzyme that has ASMT activity as well. Among several combinations of dual expression cassettes, recombinant E. coli that expressed sheep SNAT with rice COMT produced a high quantity of melatonin, which was measured in a culture medium (1.46 mg/L in response to 1 mM serotonin). This level was several orders of magnitude higher than that produced in transgenic rice and tomato overexpressing sheep SNAT and ASMT, respectively. This heterologous expression system can be widely employed to screen various putative SNAT or ASMT genes from animals and plants as well as to overproduce melatonin in various useful microorganisms.

  15. N-acetyltransferase-2 and medical history in bladder cancer cases with a suspected occupational disease (BK 1301) in Germany.

    Science.gov (United States)

    Weistenhofer, Wobbeke; Blaszkewicz, Meinolf; Bolt, Hermann M; Golka, Klaus

    2008-01-01

    In 187 bladder cancer cases reported to the employers' liability insurance association in Germany as suspected cases of an occupational disease produced by aromatic amines, N- acetyltransferase-2 (NAT2) activity status, occupational exposure data, period of latency, and clinical parameters were determined. In 83 out of 187 cases surveyed within the period 1991-1999, the NAT2 acetylator status was investigated by determining the molar ratio of an acetylated and a nonacetylated caffeine metabolite in urine (phenotyping) and/or by NAT2 genotyping according to standard polymerase chain reaction (PCR) protocol. The proportion of slow NAT2 acetylators in the surveyed 83 bladder cancer cases was 67%. In the entire group of surveyed 187 cases, mean duration of exposure was 17.6 yr and mean period of latency was 34.7 yr. Occupational exposures to potential bladder carcinogens were observed in 73 occupations, including chemical industry (25%), and occupations as a painter and/or varnisher (23%) were most often encountered. In 12% of the surveyed bladder cancer cases, a second primary malignancy was observed. The NAT2 distribution observed in the 83 cases is comparable to the proportion in 40 occupationally exposed bladder cancer cases in a Department of Urology located close to a former German production site of benzidine-based azo dyes, but higher than in most studies involving NAT2 genetic status in bladder cancer cases.

  16. Catalytic Mechanism of Perosamine N-Acetyltransferase Revealed by High-Resolution X-ray Crystallographic Studies and Kinetic Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Thoden, James B.; Reinhardt, Laurie A.; Cook, Paul D.; Menden, Patrick; Cleland, W.W.; Holden, Hazel M. (UW); (Mount Union); (UW-MED)

    2012-09-17

    N-Acetylperosamine is an unusual dideoxysugar found in the O-antigens of some Gram-negative bacteria, including the pathogenic Escherichia coli strain O157:H7. The last step in its biosynthesis is catalyzed by PerB, an N-acetyltransferase belonging to the left-handed {beta}-helix superfamily of proteins. Here we describe a combined structural and functional investigation of PerB from Caulobacter crescentus. For this study, three structures were determined to 1.0 {angstrom} resolution or better: the enzyme in complex with CoA and GDP-perosamine, the protein with bound CoA and GDP-N-acetylperosamine, and the enzyme containing a tetrahedral transition state mimic bound in the active site. Each subunit of the trimeric enzyme folds into two distinct regions. The N-terminal domain is globular and dominated by a six-stranded mainly parallel {beta}-sheet. It provides most of the interactions between the protein and GDP-perosamine. The C-terminal domain consists of a left-handed {beta}-helix, which has nearly seven turns. This region provides the scaffold for CoA binding. On the basis of these high-resolution structures, site-directed mutant proteins were constructed to test the roles of His 141 and Asp 142 in the catalytic mechanism. Kinetic data and pH-rate profiles are indicative of His 141 serving as a general base. In addition, the backbone amide group of Gly 159 provides an oxyanion hole for stabilization of the tetrahedral transition state. The pH-rate profiles are also consistent with the GDP-linked amino sugar substrate entering the active site in its unprotonated form. Finally, for this investigation, we show that PerB can accept GDP-3-deoxyperosamine as an alternative substrate, thus representing the production of a novel trideoxysugar.

  17. Modification of N-acetyltransferases and glutathione S-transferases by coffee components: possible relevance for cancer risk.

    Science.gov (United States)

    Huber, Wolfgang W; Parzefall, Wolfram

    2005-01-01

    Enzymes of xenobiotic metabolism are involved in the activation and detoxification of carcinogens and can play a pivotal role in the susceptibility of individuals toward chemically induced cancer. Differences in such susceptibility are often related to genetically predetermined enzyme polymorphisms but may also be caused by enzyme induction or inhibition through environmental factors or in the frame of chemopreventive intervention. In this context, coffee consumption, as an important lifestyle factor, has been under thorough investigation. Whereas the data on a potential procarcinogenic effect in some organs remained inconclusive, epidemiology has clearly revealed coffee drinkers to be at a lower risk of developing cancers of the colon and the liver and possibly of several other organs. The underlying mechanisms of such chemoprotection, modifications of xenobiotic metabolism in particular, were further investigated in rodent and in vitro models, as a result of which several individual chemoprotectants out of the >1000 constituents of coffee were identified as well as some strongly metabolized individual carcinogens against which they specifically protected. This chapter discusses the chemoprotective effects of several coffee components and whole coffee in association with modifications of the usually protective glutathione-S-transferase (GST) and the more ambivalent N-acetyltransferase (NAT). A key role is played by kahweol and cafestol (K/C), two diterpenic constituents of the unfiltered beverage that were found to reduce mutagenesis/tumorigenesis by strongly metabolized compounds, such as 2-amino-1-methyl-6-phenylimidazo-[4,5-b]pyridine, 7,12-dimethylbenz[a]anthracene, and aflatoxin B(1), and to cause various modifications of xenobiotic metabolism that were overwhelmingly beneficial, including induction of GST and inhibition of NAT. Other coffee components such as polyphenols and K/C-free coffee are also capable of increasing GST and partially of inhibiting NAT

  18. N-Acetyltransferase 2 genotype, exfoliated urothelial cells and benzidine exposure.

    Science.gov (United States)

    Ma, Qing-wen; Lin, Guo-fang; Chen, Ji-gang; Guo, Wei-Chao; Qin, Yi-qiu; Golka, Klaus; Shen, Jian-hua

    2012-01-01

    Most studies report an association of the slow N-acetyltransferase 2 (NAT2) status with elevated bladder cancer risk. In this study, NAT2 genotypes and the decades-long records of Papanicolaou's grading of exfoliated urothelial cells in a former benzidine-exposed cohort of the Shanghai dyestuff industry (29 bladder cancer patients; 307 non-cancer cohort members, some of them presenting different grades of pre-malignant alterations of exfoliated urothelial cells) were investigated. The cohort members had been enrolled in regular medical surveillance since mid-1980s. No overall increase of slow NAT2 genotypes in the former benzidine-exposed bladder cancer patients was found, compared with non-diseased members of the same cohort. A lower presentation of the homozygous wild genotype NAT2 4/4 was observed in bladder cancer patients, compared with non-diseased members with averaged Papanicolaou's grading (APG)3 II (OR=0.31, 95 percent CI 0.10-0.96, p=0.034) or with APG less than II (OR=0.36,95 percent CI 0.12-1.10, p=0.063). Nevertheless, neither a protective influence of rapid NAT2 genotypes on bladder cancer risk nor on pre-malignant cytological alterations could be confirmed by the present data.

  19. [Evaluation of a caffeine test for determining the phenotype of N-acetyltransferase].

    Science.gov (United States)

    Gascon, M P; Leemann, T; Dayer, P

    1987-12-05

    Xenobiotic acetylation by N-acetyltransferase is genetically controlled. This polymorphism governs the intestinal and liver metabolism of numerous amines. The use of caffeine, a ubiquitous and nontoxic amine, has been proposed as a probe for phenotyping. The aim of the present study is to evaluate this test and to identify the metabolite of caffeine used as substrate by the polymorphic enzyme. - A cup of coffee, tea or Coca-Cola is administered to fasting subjects. The molar ratio of two metabolites of caffeine (AFMU and 1X) is determined on a spot urine sample 4-6 hours later by means of a UV liquid chromatographic assay. In a reference population (n = 63), the distribution of molar ratios is trimodal with frequencies of 0.14, 0.35 and 0.51. These results correlate with those obtained by the classic isoniazid test. However, in vitro experiments in human liver subcellular fractions did not lead to the identification of a xanthine as the precursor of the acetylated metabolite.

  20. Inference of Functionally-Relevant N-acetyltransferase Residues Based on Statistical Correlations.

    Science.gov (United States)

    Neuwald, Andrew F; Altschul, Stephen F

    2016-12-01

    Over evolutionary time, members of a superfamily of homologous proteins sharing a common structural core diverge into subgroups filling various functional niches. At the sequence level, such divergence appears as correlations that arise from residue patterns distinct to each subgroup. Such a superfamily may be viewed as a population of sequences corresponding to a complex, high-dimensional probability distribution. Here we model this distribution as hierarchical interrelated hidden Markov models (hiHMMs), which describe these sequence correlations implicitly. By characterizing such correlations one may hope to obtain information regarding functionally-relevant properties that have thus far evaded detection. To do so, we infer a hiHMM distribution from sequence data using Bayes' theorem and Markov chain Monte Carlo (MCMC) sampling, which is widely recognized as the most effective approach for characterizing a complex, high dimensional distribution. Other routines then map correlated residue patterns to available structures with a view to hypothesis generation. When applied to N-acetyltransferases, this reveals sequence and structural features indicative of functionally important, yet generally unknown biochemical properties. Even for sets of proteins for which nothing is known beyond unannotated sequences and structures, this can lead to helpful insights. We describe, for example, a putative coenzyme-A-induced-fit substrate binding mechanism mediated by arginine residue switching between salt bridge and π-π stacking interactions. A suite of programs implementing this approach is available (psed.igs.umaryland.edu).

  1. N-acetyltransferase 1 in colon and rectal cancer cases from an industrialized area.

    Science.gov (United States)

    Roemer, Hermann C; Weistenhofer, Wobbeke; Lohlein, Dietrich; Geller, Frank; Blomeke, Brunhilde; Golka, Klaus

    2008-01-01

    Colon and rectal cancers are both associated with genetic as well as nutritional, occupational, and environmental factors. Aromatic amines and heterocyclic amines are established colorectal carcinogens. The polymorphic enzyme N-acetyltransferase 1 (NAT1) contributes to heterocyclic amine metabolism in the human colon. Thereby, NAT1 may influence the risk for development of colorectal cancer. The distribution of NAT1 genotypes was determined in 107 colon cancer cases, 77 rectal cancer cases, and 185 controls (suffering from nonmalignant diseases) by standard methods. In addition, possible occupational and nonoccupational risk factors were determined by a personal interview. Cancer cases and controls were derived from an area of former coal, iron, and steel industries, which is known for elevated colon cancer mortality. The proportions of NAT1*4/*4 genotype were 72% in controls, 75% in rectal cancer cases, and 72% in colon cancer cases. The proportions of the NAT1*4/*10 genotype were 17.8% in controls, 12.9% in rectal cancer cases, and 14% in colon cancer cases. Combinations of the determined NAT1 alleles *3/*3, *3/*10, *4/*3, *4/*11, *10/*10 and *11/*11 contributed to 10.2% of the genotypes in controls, 12.1% in rectal cancer cases, and 14% in colon cancer cases. In contrast to another study on healthy German volunteers, the NAT1*4/*4 genotype (wild type) is overrepresented. This might be due to the variation in the proportion of NAT1 alleles in the general population. The present study does not support a relevant impact of the NAT1 genotype on colorectal cancer risk development in the study area.

  2. N-Acetyltransferase 2 gene polymorphism in a group of senile dementia patients in Shanghai suburb

    Institute of Scientific and Technical Information of China (English)

    Wei-chao GUO; Guo-fang LIN; Yong-lin ZHA; Ke-jian LOU; Qing-wen MA; Jian-hua SHEN

    2004-01-01

    AIM: To investigate the possible association of hereditary polymorphism of N-acetyltransferase 2 (NAT2) gene with the susceptibility towards senile dementia in farmer population of Shanghai suburb. METHODS: NAT2 gene genotyping was performed at 7 major polymorphic loci (G191A, C282T, T341C, C481T, G590A, A803G, and .G857A) with a polymerase chain reaction-based restriction fragment length polymorphism based procedure in 2 groups of farmer subjects in Shanghai suburb. A group of 51 diagnosed dementia patients [comprising 29 sporadic Alzheimer disease(AD) patients and 22 sporadic vascular dementia (VD) patients] and a group of 112 healthy individuals were in the same area. RESULTS: The homogenous rapid genotypes (R/R, including*4/*4, *13/*13, and *4/*13) was found over-present in both groups of patients, compared with healthy individuals, for all farmer dementia patients, 52.9 %vs 33.0 %, P=0.016, OR (95 % CI): 2.28(1.16-4.48); for AD group only, 51.7 % vs 33.0 %, P=0.063, OR (95 %CI): 2.18 (0.95-4.97); for VD group 54.5 % vs 33.0 %, P=0.055, OR (95 % CI): 2.43 (0.96-2.43). The significant frequency difference of genotype *4/* 7B between farmer dementia patients and healthy individuals, and that of solo-alleles *13, and *7B were observed between the healthy individuals and both groups of dementia patients.CONCLUSION: Our data suggest the involvement of various NAT2 rapid-acetylating genotypes in the individual susceptibility to senile dementia. Variant genotypes of NAT2 might serve as a hereditary risk factor for AD and VD in Chinese population.

  3. N-acetyltransferase 2, exposure to aromatic and heterocyclic amines, and receptor-defined breast cancer.

    Science.gov (United States)

    Rabstein, Sylvia; Brüning, Thomas; Harth, Volker; Fischer, Hans-Peter; Haas, Susanne; Weiss, Tobias; Spickenheuer, Anne; Pierl, Christiane; Justenhoven, Christina; Illig, Thomas; Vollmert, Caren; Baisch, Christian; Ko, Yon-Dschun; Hamann, Ute; Brauch, Hiltrud; Pesch, Beate

    2010-03-01

    The role of N-acetyltransferase 2 (NAT2) polymorphism in breast cancer is still unclear. We explored the associations between potential sources of exposure to aromatic and heterocyclic amines (AHA), acetylation status and receptor-defined breast cancer in 1020 incident cases and 1047 population controls of the German GENICA study. Acetylation status was assessed as slow or fast. Therefore, NAT2 haplotypes were estimated using genotype information from six NAT2 polymorphisms. Most probable haplotypes served as alleles for the deduction of NAT2 acetylation status. The risks of developing estrogen receptor alpha (ER) and progesterone receptor (PR)-positive or negative tumors were estimated for tobacco smoking, consumption of red meat, grilled food, coffee, and tea, as well as expert-rated occupational exposure to AHA with logistic regression conditional on age and adjusted for potential confounders. Joint effects of these factors and NAT2 acetylation status were investigated. Frequent consumption of grilled food and coffee showed higher risks in slow acetylators for receptor-negative tumors [grilled food: ER-: odds ratio (OR) 2.57, 95% confidence interval (CI) 1.07-6.14 for regular vs. rare; coffee: ER-: OR 2.55, 95% CI 1.22-5.33 for >or=4 vs. 0 cups/day]. We observed slightly higher risks for never smokers that are fast acetylators for receptor-positive tumors compared with slow acetylators (ER-: OR 1.32, 95% CI 1.00-1.73). Our results support differing risk patterns for receptor-defined breast cancer. However, the modifying role of NAT2 for receptor-defined breast cancer is difficult to interpret in the light of complex mixtures of exposure to AHA.

  4. Lewis acid catalyzed cyclization of glycals/2-deoxy-D-ribose with arylamines: additional findings on product structure and reaction diastereoselectivity.

    Science.gov (United States)

    Du, Chengtang; Li, Fulong; Zhang, Xuefeng; Hu, Wenxiang; Yao, Qizheng; Zhang, Ao

    2011-11-01

    The cyclization reactions of arylamines with 2-deoxy-D-ribose or glycals were reinvestigated in the current report. In the montmorillonite KSF- or InCl(3)-initiated reactions of 2-deoxy-D-ribose with arylamines, a pair of diastereomeric tetrahydro-2H-pyran-fused tetrahydroquinolines was obtained in a nearly 1:1 ratio where the structure of one diastereomer was incorrectly assigned in the literature. Meanwhile, the diastereoselectivity in InBr(3)-catalyzed cyclization of glycals with arylamines was also incorrectly reported previously. It was found that high diastereomeric selectivity was achieved only when a C5-substituted glycal was used; otherwise, a pair of diastereomers was obtained in moderate yield with 1:1 diastereomeric ratio. Furthermore, tetrahydrofuran-fused tetrahydroquinolines 5b and 5b' were also prepared successfully by using TBDPS-protected ribose as the glycal precursor and montmorillonite KSF as the activator.

  5. N-acetyltransferase-dependent activation of 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine: formation of 2-amino-1-methyl-6-(5-hydroxy)phenylimidazo [4,5-b]pyridine, a possible biomarker for the reactive dose of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

    DEFF Research Database (Denmark)

    Frandsen, Henrik Lauritz; Alexander, J.

    2000-01-01

    2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mutagenic and carcinogenic heterocyclic amine formed during ordinary cooking. PhIP is metabolically activated to the ultimate mutagenic metabolite by CYP P450-mediated N-hydroxylation followed by phase II esterification, Incubation of N...

  6. The human serotonin N-acetyltransferase (EC 2.3.1.87) gene (AANAT): Structure, chromosomal localization, and tissue expression

    Energy Technology Data Exchange (ETDEWEB)

    Coon, S.L.; Bernard, M.; Roseboom, P.H. [National Institutes of Health, Bethesda, MD (United States)] [and others

    1996-05-15

    Serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase, AA-NAT, HGMW-approved symbol AANAT;EC 2.3.1.87) is the penultimate enzyme in melatonin synthesis and controls the night/day rhythm in melatonin production in the vertebrate pineal gland. We have found that the human AA-NAT gene spans {approx}2.5 kb, contains four exons, and is located at chromosome 17q25. The open reading frame encodes a 23.2-kDa protein that is {approx}80% identical to sheep and rat AA-NAT. The AA-NAT transcript ({approx}1 kb) is highly abundant in the pineal gland and is expressed at lower levels in the retina and in the Y79 retinoblastoma cell line. AA-NAT mRNA is also detectable at low levels in several brain regions and the pituitary gland, but not in several peripheral tissues examined. Brain and pituitary AA-NAT could modulate serotonin-dependent aspects of human behavior and pituitary function. 31 refs., 5 figs.

  7. Human acetyl-CoA:glucosamine-6-phosphate N-acetyltransferase 1 has a relaxed donor specificity and transfers acyl groups up to four carbons in length.

    Science.gov (United States)

    Brockhausen, Inka; Nair, Dileep G; Chen, Min; Yang, Xiaojing; Allingham, John S; Szarek, Walter A; Anastassiades, Tassos

    2016-04-01

    Glucosamine-6-phosphate N-acetyltransferase1 (GNA1) catalyses the transfer of an acetyl group from acetyl coenzyme A (AcCoA) to glucosamine-6-phosphate (GlcN6P) to form N-acetylglucosamine-6-phosphate (GlcNAc6P), which is an essential intermediate in UDP-GlcNAc biosynthesis. An analog of GlcNAc, N-butyrylglucosamine (GlcNBu) has shown healing properties for bone and articular cartilage in animal models of arthritis. The goal of this work was to examine whether GNA1 has the ability to transfer a butyryl group from butyryl-CoA to GlcN6P to form GlcNBu6P, which can then be converted to GlcNBu. We developed fluorescent and radioactive assays and examined the donor specificity of human GNA1. Acetyl, propionyl, n-butyryl, and isobutyryl groups were all transferred to GlcN6P, but isovaleryl-CoA and decanoyl-CoA did not serve as donor substrates. Site-specific mutants were produced to examine the role of amino acids potentially affecting the size and properties of the AcCoA binding pocket. All of the wild type and mutant enzymes showed activities of both acetyl and butyryl transfer and can therefore be used for the enzymatic synthesis of GlcNBu for biomedical applications.

  8. Structural and functional analysis of the yeast N-acetyltransferase Mpr1 involved in oxidative stress tolerance via proline metabolism.

    Science.gov (United States)

    Nasuno, Ryo; Hirano, Yoshinori; Itoh, Takafumi; Hakoshima, Toshio; Hibi, Takao; Takagi, Hiroshi

    2013-07-16

    Mpr1 (sigma1278b gene for proline-analog resistance 1), which was originally isolated as N-acetyltransferase detoxifying the proline analog L-azetidine-2-carboxylate, protects yeast cells from various oxidative stresses. Mpr1 mediates the L-proline and L-arginine metabolism by acetylating L-Δ(1)-pyrroline-5-carboxylate, leading to the L-arginine-dependent production of nitric oxide, which confers oxidative stress tolerance. Mpr1 belongs to the Gcn5-related N-acetyltransferase (GNAT) superfamily, but exhibits poor sequence homology with the GNAT enzymes and unique substrate specificity. Here, we present the X-ray crystal structure of Mpr1 and its complex with the substrate cis-4-hydroxy-L-proline at 1.9 and 2.3 Å resolution, respectively. Mpr1 is folded into α/β-structure with eight-stranded mixed β-sheets and six α-helices. The substrate binds to Asn135 and the backbone amide of Asn172 and Leu173, and the predicted acetyl-CoA-binding site is located near the backbone amide of Phe138 and the side chain of Asn178. Alanine substitution of Asn178, which can interact with the sulfur of acetyl-CoA, caused a large reduction in the apparent kcat value. The replacement of Asn135 led to a remarkable increase in the apparent Km value. These results indicate that Asn178 and Asn135 play an important role in catalysis and substrate recognition, respectively. Such a catalytic mechanism has not been reported in the GNAT proteins. Importantly, the amino acid substitutions in these residues increased the L-Δ(1)-pyrroline-5-carboxylate level in yeast cells exposed to heat stress, indicating that these residues are also crucial for its physiological functions. These studies provide some benefits of Mpr1 applications, such as the breeding of industrial yeasts and the development of antifungal drugs.

  9. Non-syndromic retinitis pigmentosa due to mutations in the mucopolysaccharidosis type IIIC gene, heparan-alpha-glucosaminide N-acetyltransferase (HGSNAT)

    Science.gov (United States)

    Haer-Wigman, Lonneke; Newman, Hadas; Leibu, Rina; Bax, Nathalie M.; Baris, Hagit N; Rizel, Leah; Banin, Eyal; Massarweh, Amir; Roosing, Susanne; Lefeber, Dirk J.; Zonneveld-Vrieling, Marijke N.; Isakov, Ofer; Shomron, Noam; Sharon, Dror; Den Hollander, Anneke I.; Hoyng, Carel B.; Cremers, Frans P.M.; Ben-Yosef, Tamar

    2015-01-01

    Retinitis pigmentosa (RP), the most common form of inherited retinal degeneration, is clinically and genetically heterogeneous and can appear as syndromic or non-syndromic. Mucopolysaccharidosis type IIIC (MPS IIIC) is a lethal disorder, caused by mutations in the heparan-alpha-glucosaminide N-acetyltransferase (HGSNAT) gene and characterized by progressive neurological deterioration, with retinal degeneration as a prominent feature. We identified HGSNAT mutations in six patients with non-syndromic RP. Whole exome sequencing (WES) in an Ashkenazi Jewish Israeli RP patient revealed a novel homozygous HGSNAT variant, c.370A>T, which leads to partial skipping of exon 3. Screening of 66 Ashkenazi RP index cases revealed an additional family with two siblings homozygous for c.370A>T. WES in three Dutch siblings with RP revealed a complex HGSNAT variant, c.[398G>C; 1843G>A] on one allele, and c.1843G>A on the other allele. HGSNAT activity levels in blood leukocytes of patients were reduced compared with healthy controls, but usually higher than those in MPS IIIC patients. All patients were diagnosed with non-syndromic RP and did not exhibit neurological deterioration, or any phenotypic features consistent with MPS IIIC. Furthermore, four of the patients were over 60 years old, exceeding by far the life expectancy of MPS IIIC patients. HGSNAT is highly expressed in the mouse retina, and we hypothesize that the retina requires higher HGSNAT activity to maintain proper function, compared with other tissues associated with MPS IIIC, such as the brain. This report broadens the spectrum of phenotypes associated with HGSNAT mutations and highlights the critical function of HGSNAT in the human retina. PMID:25859010

  10. Molecular Structure of WlbB, a Bacterial N-Acetyltransferase Involved in the Biosynthesis of 2,3-Diacetamido-2,3-dideoxy-d-mannuronic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Thoden, James B.; Holden, Hazel M. (UW)

    2010-09-08

    The pathogenic bacteria Pseudomonas aeruginosa and Bordetella pertussis contain in their outer membranes the rare sugar 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid. Five enzymes are required for the biosynthesis of this sugar starting from UDP-N-acetylglucosamine. One of these, referred to as WlbB, is an N-acetyltransferase that converts UDP-2-acetamido-3-amino-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NA) to UDP-2,3-diacetamido-2,3-dideoxy-D-glucuronic acid (UDP-GlcNAc3NAcA). Here we report the three-dimensional structure of WlbB from Bordetella petrii. For this analysis, two ternary structures were determined to 1.43 {angstrom} resolution: one in which the protein was complexed with acetyl-CoA and UDP and the second in which the protein contained bound CoA and UDP-GlcNAc3NA. WlbB adopts a trimeric quaternary structure and belongs to the L{beta}H superfamily of N-acyltransferases. Each subunit contains 27 {beta}-strands, 23 of which form the canonical left-handed {beta}-helix. There are only two hydrogen bonds that occur between the protein and the GlcNAc3NA moiety, one between O{sup {delta}1} of Asn 84 and the sugar C-3{prime} amino group and the second between the backbone amide group of Arg 94 and the sugar C-5{prime} carboxylate. The sugar C-3{prime} amino group is ideally positioned in the active site to attack the si face of acetyl-CoA. Given that there are no protein side chains that can function as general bases within the GlcNAc3NA binding pocket, a reaction mechanism is proposed for WlbB whereby the sulfur of CoA ultimately functions as the proton acceptor required for catalysis.

  11. N-Acetyltransferase 2 and glutathione s-transferase M1 in colon and rectal cancer cases from an industrialized area.

    Science.gov (United States)

    Golka, Klaus; Roemer, Hermann C; Weistenhöfer, Wobbeke; Blaszkewicz, Meinolf; Hammad, Seddik; Reckwitz, Thomas; Loehlein, Dietrich; Hartel, Mark; Hengstler, Jan G; Geller, Frank

    2012-01-01

    Apart from genetics, nutrition, and environment, occupational factors also play an important role in colon and rectal cancer development. The aim of this study was to examine these cancer types in an area of former coal, iron, and steel industries, which was found to display an increased incidence of colon cancer mortality. N-Acetyltransferase 2 (NAT2) and glutathione S-transferase M1 (GSTM1) genotypes were investigated in 108 colon cancer cases, 80 rectum cancer cases, and 188 controls (suffering from nonmalignant diseases). Further, in a pilot study, 28 colorectal cancer patients were NAT2 phenotyped by the caffeine test. Possible occupational and nonoccupational risk factors were investigated by a personal interview. The frequency of rapid NAT2 genotype was 35% in colon cancer cases, 47% in rectal cancer cases, and 42% in controls (GSTM1 0/0 genotype: 53, 46, and 47%, respectively). In the 29 patients with cancer in the ascending colon, 10% were of the rapid NAT2 genotype. In the pilot study the frequency of the rapid NAT2 phenotype was 49%. The only major professional group with an elevated risk was painters (colon cancer OR 2.48, 95% CI 0.4-15.23; rectal cancer OR 5.65, 95% CI 1.06-30.21). In contrast to early studies, in the present study the slow NAT2 status is overrepresented. As colorectal cancer is associated with nutrition and physical activity, present findings may be due to excessive physical heavy work and the resulting nutrition in this area.

  12. Prevalence of the N-Acetyltransferase (NAT2 gene polymorphism 282C>T in Peruvian population and health implications

    Directory of Open Access Journals (Sweden)

    Salazar-Granara Alberto

    2016-03-01

    Full Text Available Objective: To determine the frequency of the C282T polymorphism of the NAT2 gene (N acetyltransferase in Peruvian populations. Field work, focused on exploring genetic risk factor in Peruvian populations, which has influence in the response to drugs and malignancies aetiology. Material and Methods: Cross-sectional study. 166 voluntaries from Lima, Lambayeque, Apurimac, Puno, San Martin, Amazonas and Loreto were enrolled. The sampling was done by convenience and it was use the RFLP-PCR conventional technique was used. Results: The allele frequency were 54% (n=126 for C282 and 46% (n=106 for T282. For the T allele, by its orign , stand out 2 those which origins were Lima 42% (n=25, Amazonas 47% (n=16, San Martin 74% (n=28 and Apurimac 50% (n=13 (X , p>0.05. A global genotype frequency were 26.7% (n=31 for C282/C282, 56.0% (n=65 for C282/T282 and 17.2% (n=20 for T282/T282 (Hardy Weinberg Test p>0.05. By origin, Puno presented allelic imbalance (Hardy Weinberg test p0.05. Conclusion: The overall frequency of NAT2 allele T282 was 46%; San Martin had the highest prevalence (74%. The T282 allele is linked to neoplastic diseases and adverse reactions to anti-TB drugs, these results will be used for the application of pharmacogenetics in Peru

  13. Cell-free expression of human glucosamine 6-phosphate N-acetyltransferase (HsGNA1) for inhibitor screening.

    Science.gov (United States)

    Ma, Yi; Ghoshdastider, Umesh; Wang, Jufang; Ye, Wei; Dötsch, Volker; Filipek, Slawomir; Bernhard, Frank; Wang, Xiaoning

    2012-12-01

    Glucosamine 6-phosphate N-acetyltransferase (GNA1; EC 2.3.1.4) is required for the de novo synthesis of N-acetyl-d-glucosamine-6-phosphate (GlcNAc-6P), which is an essential precursor in Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) biosynthesis pathway. Therefore, GNA1 is indispensable for the viability of organisms. Here, a novel cell-free expression strategy was developed to efficiently produce large amounts of human GNA1(HsGNA1) and HsGNA1-sGFP for throughput inhibitor screening. The binding site of inhibitor glucose-6-phosphate (G6P) to hGNA was identified by simulated annealing. Subtle differences to the binding site of Aspergillius GNA1(AfGNA1) can be harnessed for inhibitor design. HsGNA1 may be also useful as an antimicrobial and chemotherapeutic target against cancer. Additionally HsGNA1 inhibitors/modulators can possibly be administered with other drugs in the next generation of personalized medicine.

  14. MicroRNAs in the pineal gland: miR-483 regulates melatonin synthesis by targeting arylalkylamine N-acetyltransferase.

    Science.gov (United States)

    Clokie, Samuel J H; Lau, Pierre; Kim, Hyun Hee; Coon, Steven L; Klein, David C

    2012-07-20

    MicroRNAs (miRNAs) play a broad range of roles in biological regulation. In this study, rat pineal miRNAs were profiled for the first time, and their importance was evaluated by focusing on the main function of the pineal gland, melatonin synthesis. Massively parallel sequencing and related methods revealed the miRNA population is dominated by a small group of miRNAs as follows: ~75% is accounted for by 15 miRNAs; miR-182 represents 28%. In addition to miR-182, miR-183 and miR-96 are also highly enriched in the pineal gland, a distinctive pattern also found in the retina. This effort also identified previously unrecognized miRNAs and other small noncoding RNAs. Pineal miRNAs do not exhibit a marked night/day difference in abundance with few exceptions (e.g. 2-fold night/day differences in the abundance of miR-96 and miR-182); this contrasts sharply with the dynamic 24-h pattern that characterizes the pineal transcriptome. During development, the abundance of most pineal gland-enriched miRNAs increases; however, there is a marked decrease in at least one, miR-483. miR-483 is a likely regulator of melatonin synthesis, based on the following. It inhibits melatonin synthesis by pinealocytes in culture; it acts via predicted binding sites in the 3"-UTR of arylalkylamine N-acetyltransferase (Aanat) mRNA, the penultimate enzyme in melatonin synthesis, and it exhibits a developmental profile opposite to that of Aanat transcripts. Additionally, a miR-483 targeted antagonist increased melatonin synthesis in neonatal pinealocytes. These observations support the hypothesis that miR-483 suppresses Aanat mRNA levels during development and that the developmental decrease in miR-483 abundance promotes melatonin synthesis.

  15. Structural analysis of PseH, the Campylobacter jejuni N-acetyltransferase involved in bacterial O-linked glycosylation.

    Science.gov (United States)

    Song, Wan Seok; Nam, Mi Sun; Namgung, Byeol; Yoon, Sung-il

    2015-03-20

    Campylobacter jejuni is a bacterium that uses flagella for motility and causes worldwide acute gastroenteritis in humans. The C. jejuni N-acetyltransferase PseH (cjPseH) is responsible for the third step in flagellin O-linked glycosylation and plays a key role in flagellar formation and motility. cjPseH transfers an acetyl group from an acetyl donor, acetyl coenzyme A (AcCoA), to the amino group of UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine to produce UDP-2,4-diacetamido-2,4,6-trideoxy-β-L-altropyranose. To elucidate the catalytic mechanism of cjPseH, crystal structures of cjPseH alone and in complex with AcCoA were determined at 1.95 Å resolution. cjPseH folds into a single-domain structure of a central β-sheet decorated by four α-helices with two continuously connected grooves. A deep groove (groove-A) accommodates the AcCoA molecule. Interestingly, the acetyl end of AcCoA points toward an open space in a neighboring shallow groove (groove-S), which is occupied by extra electron density that potentially serves as a pseudosubstrate, suggesting that the groove-S may provide a substrate-binding site. Structure-based comparative analysis suggests that cjPseH utilizes a unique catalytic mechanism of acetylation that has not been observed in other glycosylation-associated acetyltransferases. Thus, our studies on cjPseH will provide valuable information for the design of new antibiotics to treat C. jejuni-induced gastroenteritis.

  16. Cigarette smoking, N-acetyltransferase 2 genotypes, and breast cancer risk: pooled analysis and meta-analysis.

    Science.gov (United States)

    Ambrosone, Christine B; Kropp, Silke; Yang, Jun; Yao, Song; Shields, Peter G; Chang-Claude, Jenny

    2008-01-01

    Approximately 10 years ago, it was noted that smoking increased risk of breast cancer among women with N-acetyltransferase 2 (NAT2) slow acetylation genotypes. This report was followed by a number of studies to address this question. We pooled data from 10 existing studies and also conducted a meta-analysis of 13 studies published from 1996 to October 2006 that were conducted among women, were published in English, and had adequate information on smoking and NAT2 genotyping. Raw data were requested from authors. Unconditional logistic regression was done for pooled analysis, and random effect models was done for meta-analysis. Study heterogeneity was assessed, and sensitivity tests were done when subgroups were excluded from the analysis. In the pooled analysis, there was a significant interaction between smoking, NAT2 genotype, and risk of breast cancer [pack-years (continuous variable, P(interaction) = 0.03)], with higher pack-years significantly associated with an increased risk of breast cancer among women with NAT2 slow genotypes (pooled analysis relative risk, 1.49; 95% confidence interval, 1.08-2.04). These findings were supported by the meta-analysis including all studies; pack-years were significantly associated with risk among slow acetylators in a dose-dependent fashion (meta-analysis relative risk, 1.44; 95% confidence interval, 1.23-1.68 for > or =20 pack-years versus never smokers), but not among rapid acetylators. Similar relationships were noted for smoking status (ever, never) and duration of smoking. Our results show that cigarette smoking is associated with an increase in breast cancer risk among women with NAT2 slow acetylation genotypes. Because slow NAT2 genotypes are present in 50% to 60% of Caucasian populations, smoking is likely to play an important role in breast cancer etiology.

  17. Structural analysis of PseH, the Campylobacter jejuni N-acetyltransferase involved in bacterial O-linked glycosylation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Wan Seok; Nam, Mi Sun; Namgung, Byeol [Department of Systems Immunology, College of Biomedical Science, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Yoon, Sung-il, E-mail: sungil@kangwon.ac.kr [Department of Systems Immunology, College of Biomedical Science, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2015-03-20

    Campylobacter jejuni is a bacterium that uses flagella for motility and causes worldwide acute gastroenteritis in humans. The C. jejuni N-acetyltransferase PseH (cjPseH) is responsible for the third step in flagellin O-linked glycosylation and plays a key role in flagellar formation and motility. cjPseH transfers an acetyl group from an acetyl donor, acetyl coenzyme A (AcCoA), to the amino group of UDP-4-amino-4,6-dideoxy-N-acetyl-β-L-altrosamine to produce UDP-2,4-diacetamido-2,4,6-trideoxy-β-L-altropyranose. To elucidate the catalytic mechanism of cjPseH, crystal structures of cjPseH alone and in complex with AcCoA were determined at 1.95 Å resolution. cjPseH folds into a single-domain structure of a central β-sheet decorated by four α-helices with two continuously connected grooves. A deep groove (groove-A) accommodates the AcCoA molecule. Interestingly, the acetyl end of AcCoA points toward an open space in a neighboring shallow groove (groove-S), which is occupied by extra electron density that potentially serves as a pseudosubstrate, suggesting that the groove-S may provide a substrate-binding site. Structure-based comparative analysis suggests that cjPseH utilizes a unique catalytic mechanism of acetylation that has not been observed in other glycosylation-associated acetyltransferases. Thus, our studies on cjPseH will provide valuable information for the design of new antibiotics to treat C. jejuni-induced gastroenteritis. - Highlights: • cjPseH adopts a single-domain structure of a central β-sheet decorated by α-helices. • cjPseH features two continuously connected grooves on the protein surface. • Acetyl coenzyme A (AcCoA) binds into a deep groove of cjPseH in an ‘L’ shape. • The acetyl end of AcCoA points to a wide groove, a potential substrate-binding site.

  18. Heritability of caffeine metabolism

    DEFF Research Database (Denmark)

    Matthaei, Johannes; Tzvetkov, Mladen V; Strube, Jakob;

    2016-01-01

    Heritability of caffeine pharmacokinetics and CYP1A2 activity is controversial. Here we analyzed the pharmacokinetics of caffeine, an in vivo probe drug for CYP1A2 and arylamine N-acetyltransferase 2 (NAT2) activity, in monozygotic and dizygotic twins. In the entire group, common and unique envir...

  19. Palladium-catalyzed aerobic dehydrogenative aromatization of cyclohexanone imines to arylamines.

    Science.gov (United States)

    Hajra, Alakananda; Wei, Ye; Yoshikai, Naohiko

    2012-11-02

    Dehydrogenative aromatization of cyclohexanone imines to arylamines has been achieved using a palladium catalyst under aerobic conditions. The reaction is applicable to a variety of imines that are either preformed or generated in situ from cyclohexanone derivatives and aryl or alkylamines.

  20. Base-oxidant promoted metal-free N-demethylation of arylamines

    Indian Academy of Sciences (India)

    VINAYAK BOTLA; CHIRANJEEVI BARREDDI; RAMANA V DAGGUPATI; CHANDRASEKHARAM MALAPAKA

    2016-09-01

    A metal-free oxidative N-demethylation of arylamines with triethylamine as a base and tert-butyl hydroperoxide (TBHP) as oxidant is reported in this paper. The reaction is general, practical, inexpensive, non-toxic, and the method followed is environmentally benign, with moderate to good yields.

  1. Circadian dynamics of the cone-rod homeobox (CRX) transcription factor in the rat pineal gland and its role in regulation of arylalkylamine N-acetyltransferase (AANAT).

    Science.gov (United States)

    Rohde, Kristian; Rovsing, Louise; Ho, Anthony K; Møller, Morten; Rath, Martin F

    2014-08-01

    The cone-rod homeobox (Crx) gene encodes a transcription factor in the retina and pineal gland. Crx deficiency influences the pineal transcriptome, including a reduced expression of arylalkylamine N-acetyltransferase (Aanat), a key enzyme in nocturnal pineal melatonin production. However, previous functional studies on pineal Crx have been performed in melatonin-deficient mice. In this study, we have investigated the role of Crx in the melatonin-proficient rat pineal gland. The current study shows that pineal Crx transcript levels exhibit a circadian rhythm with a peak in the middle of the night, which is transferred into daily changes in CRX protein. The study further shows that the sympathetic innervation of the pineal gland controls the Crx rhythm. By use of adenovirus-mediated short hairpin RNA gene knockdown targeting Crx mRNA in primary rat pinealocyte cell culture, we here show that intact levels of Crx mRNA are required to obtain high levels of Aanat expression, whereas overexpression of Crx induces Aanat transcription in vitro. This regulatory function of Crx is further supported by circadian analysis of Aanat in the pineal gland of the Crx-knockout mouse. Our data indicate that the rhythmic nature of pineal CRX protein may directly modulate the daily profile of Aanat expression by inducing nighttime expression of this enzyme, thus facilitating nocturnal melatonin synthesis in addition to its role in ensuring a correct tissue distribution of Aanat expression.

  2. Daily oscillation and photoresponses of clock gene, Clock, and clock-associated gene, arylalkylamine N-acetyltransferase gene transcriptions in the rat pineal gland.

    Science.gov (United States)

    Wang, Guo-Qing; Du, Yu-Zhen; Tong, Jian

    2007-01-01

    This study was conducted to investigate the circadian rhythms and light responses of Clock and arylalkylamine N-acetyltransferase (NAT) gene expressions in the rat pineal gland under the environmental conditions of a 12 h light (05:00-17:00 h): 12 h-dark (17:00-05:00 h) cycle (LD) and constant darkness (DD). The pineal gland of Sprague-Dawley rats housed under a LD regime (n=42) for four weeks and of a regime (n=42) for eight weeks were sampled at six different times, every 4 h (n=7 animals per time point), during a 24 h period. Total RNA was extracted from each sample, and the semiquantitative reverse transcription polymerase chain reaction (RT-PCR) was used to determine temporal changes in mRNA levels of Clock and NAT genes during different circadian or zeitgeber times. The data and parameters were analyzed by the cosine function software, Clock Lab software, and the amplitude F test was used to reveal the circadian rhythm. In the DD or LD condition, both the Clock and NAT mRNA levels in the pineal gland showed robust circadian oscillation (ppineal gland were significantly reduced (ppineal gland (p>0.05). These findings indicate that the transcriptions of Clock and NAT genes in the pineal gland not only show remarkably synchronous endogenous circadian rhythmic changes, but also respond to the ambient light signal in a reduced manner.

  3. [Circadian rhythms and light responses of clock gene and arylalkylamine N-acetyltransferase gene expressions in the pineal gland of rats].

    Science.gov (United States)

    Wang, Guo-Qing; Du, Yu-Zhen; Tong, Jian

    2005-02-25

    This study was to investigate the circadian rhythms and light responses of Clock gene and arylalkylamine N-acetyltransferase (NAT) gene expressions in the rat pineal gland under the 12 h-light : 12 h-dark cycle condition (LD) and constant darkness (DD). Sprague-Dawley rats housed under the light regime of LD (n=36) for 4 weeks and of DD (n=36) for 8 weeks were sampled for the pineal gland once a group (n=6) every 4 h in a circadian day. The total RNA was extracted from each sample and the semiquantitative reverse transcription polymerase chain reaction (RT-PCR) was used to determine the temporal changes in mRNA levels of Clock and NAT genes during different circadian times or zeitgeber times. The data were analysed by the cosine function software, Clock Lab software and the amplitude F test was used to reveal the circadian rhythm. The main results obtained are as follows. (1) In DD or LD condition, both of Clock and NAT genes mRNA levels in the pineal gland showed robust circadian oscillation (Ppineal gland were significantly reduced (Ppineal gland (P> 0.05). These findings suggest that the expressions of Clock and NAT genes in the pineal gland not only show remarkably synchronous endogenous circadian rhythmic changes, but also response to the ambient light signal in a reduced manner.

  4. Nanoparticle abraxane possesses impaired proliferation in A549 cells due to the underexpression of glucosamine 6-phosphate N-acetyltransferase 1 (GNPNAT1/GNA1)

    Science.gov (United States)

    Zhao, Minzhi; Li, Haiyun; Ma, Yan; Gong, He; Yang, Shu; Fang, Qiaojun; Hu, Zhiyuan

    2017-01-01

    Abraxane (Abr), a US Food and Drug Administration-approved albumin-bound nanoparticle applied for the treatment of non-small-cell lung cancer, has been reported to be more effective than paclitaxel (PTX). To further understand the molecular mechanisms that produce this superior drug efficacy of Abr, a quantitative proteomic approach has been applied to investigate the global protein expression profiles of lung cancer cell A549 treated with Abr and PTX. Only one protein, namely, glucosamine 6-phosphate N-acetyltransferase 1 (GNA1), showed significant differential expression (P<0.05) in the cutoff of 2.0 fold, suggesting that Abr can be used safely as a substitute for PTX. GNA1 is a key enzyme in the biosynthesis of uridine diphosphate-N-acetylglucosamine, which is an important donor substrate for N-linked glycosylation and has several important functions such as embryonic development and growth. Albumin plays a major role in the regulation of this protein. In summary, this study first shows that the superior drug effect of Abr is mainly due to the downregulation of GNA1, which causes proliferative delay and cell adhesion defect. It is also noteworthy that the deficiency of GNA1 might reduce insulin secretion which correlates with type 2 diabetes.

  5. Transgenic tobacco simultaneously overexpressing glyphosate N-acetyltransferase and 5-enolpyruvylshikimate-3-phosphate synthase are more resistant to glyphosate than those containing one gene.

    Science.gov (United States)

    Liu, Yunjun; Cao, Gaoyi; Chen, Rongrong; Zhang, Shengxue; Ren, Yuan; Lu, Wei; Wang, Jianhua; Wang, Guoying

    2015-08-01

    5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) and glyphosate N-acetyltransferase (GAT) can detoxify glyphosate by alleviating the suppression of shikimate pathway. In this study, we obtained transgenic tobacco plants overexpressing AM79 aroA, GAT, and both of them, respectively, to evaluate whether overexpression of both genes could confer transgenic plants with higher glyphosate resistance. The transgenic plants harboring GAT or AM79 aroA, respectively, showed good glyphosate resistance. As expected, the hybrid plants containing both GAT and AM79 aroA exhibited improved glyphosate resistance than the transgenic plants overexpressing only a single gene. When grown on media with high concentration of glyphosate, seedlings containing a single gene were severely inhibited, whereas plants expressing both genes were affected less. When transgenic plants grown in the greenhouse were sprayed with glyphosate, less damage was observed for the plants containing both genes. Metabolomics analysis showed that transgenic plants containing two genes could maintain the metabolism balance better than those containing one gene after glyphosate treatment. Glyphosate treatment did not lead to a huge increase of shikimate contents of tobacco leaves in transgenic plants overexpressing two genes, whereas significant increase of shikimate contents in transgenic plants containing only a single gene was observed. These results demonstrated that pyramiding both aroA and GAT in transgenic plants can enhance glyphosate resistance, and this strategy can be used for the development of transgenic glyphosate-resistant crops.

  6. Small angle X-ray scattering data and structure factor fitting for the study of the quaternary structure of the spermidine N-acetyltransferase SpeG

    Directory of Open Access Journals (Sweden)

    Steven Weigand

    2016-03-01

    Full Text Available Here we describe the treatment of the small-angle X-ray Scattering (SAXS data used during SpeG quaternary structure study as part of the research article “Substrate induced allosteric change in the quaternary structure of the spermidine N-acetyltransferase SpeG” published in Journal of Molecular Biology [1]. These data were collected on two separate area detectors as separate dilution series of the SpeG and the SpeG with spermine samples along with data from their companion buffers. The data were radially integrated, corrected for incident beam variation, and scaled to absolute units. After subtraction of volume-fraction scaled buffer scattering and division by the SpeG concentration, multiple scattering curves free of an inter-molecular structure factor were derived from the dilution series. Rather than extrapolating to infinite dilution, the structure factor contribution was estimated by fitting to the full set of data provided by dividing the scattering curves of a dilution series by the curve from the most dilute sample in that series.

  7. Modifying CH3NH3PbBr3 nanocrystals with arylamines

    Science.gov (United States)

    Zhu, Ruimin; Liu, Heyuan; Shen, Li; Sun, Dejun; Li, Xiyou

    2017-04-01

    Chemically decorating CH3NH3PbBr3 with a group of para-substituted arylamine (R-An) was investigated, where R ranges from electron-withdrawing trifluoromethoxy(-CF3O), to hydrogen or electron-donating ethoxy (-EtO). Different ratios of R-An ammonium bromide and methylammonium bromide (MA) (R-An/MA=3/7, 4/6, 5/5, 6/4 and 7/3) were tested. XRD patterns revealed that the perovskite nanocomposite were cubic with good crystallinity. TEM and photoluminescence suggested that the perovskite nanocrystals were composed of 2D layered and 3D bulk structures. 1H NMR and TGA experiments revealed that the non-substituted aniline can readily adsorb to the surface of perovskite at any ratios between R-An and MA. But an EtOAn/MA ratio ≥1 is needed to anchor the EOAn molecules on the surface of perovskite. For the arylamine with the electron-withdrawing -CF3O group, it cannot adsorb to the surface of the perovskite at any concentrations. This result reveals that both steric hindrance and alkalinity can affect the anchoring of arylamine on the surface of CH3NH3PbBr3 perovskite. I-V curves of the perovskite nanocrystal films prepared by spin coating suggest that proper surface modification can increase the conductivity significantly.

  8. Nanoparticle abraxane possesses impaired proliferation in A549 cells due to the underexpression of glucosamine 6-phosphate N-acetyltransferase 1 (GNPNAT1/GNA1

    Directory of Open Access Journals (Sweden)

    Zhao MZ

    2017-03-01

    Full Text Available Minzhi Zhao,* Haiyun Li,* Yan Ma, He Gong, Shu Yang, Qiaojun Fang, Zhiyuan Hu Chinese Academy of Sciences Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, People’s Republic of China *These authors contributed equally to this work Abstract: Abraxane (Abr, a US Food and Drug Administration-approved albumin-bound nanoparticle applied for the treatment of non-small-cell lung cancer, has been reported to be more effective than paclitaxel (PTX. To further understand the molecular mechanisms that produce this superior drug efficacy of Abr, a quantitative proteomic approach has been applied to investigate the global protein expression profiles of lung cancer cell A549 treated with Abr and PTX. Only one protein, namely, glucosamine 6-phosphate N-acetyltransferase 1 (GNA1, showed significant differential expression (P<0.05 in the cutoff of 2.0 fold, suggesting that Abr can be used safely as a substitute for PTX. GNA1 is a key enzyme in the biosynthesis of uridine diphosphate-N-acetylglucosamine, which is an important donor substrate for N-linked glycosylation and has several important functions such as embryonic development and growth. Albumin plays a major role in the regulation of this protein. In summary, this study first shows that the superior drug effect of Abr is mainly due to the downregulation of GNA1, which causes proliferative delay and cell adhesion defect. It is also noteworthy that the deficiency of GNA1 might reduce insulin secretion which correlates with type 2 diabetes. Keywords: quantitative proteomics, nano-drug, drug efficacy, lung cancer, molecular mechanisms, abraxane

  9. N-acetyltransferase (nat) is a critical conjunct of photoperiodism between the circadian system and endocrine axis in Antheraea pernyi.

    Science.gov (United States)

    Mohamed, Ahmed A M; Wang, Qiushi; Bembenek, Jadwiga; Ichihara, Naoyuki; Hiragaki, Susumu; Suzuki, Takeshi; Takeda, Makio

    2014-01-01

    Since its discovery in 1923, the biology of photoperiodism remains a mystery in many ways. We sought the link connecting the circadian system to an endocrine switch, using Antheraea pernyi. PER-, CLK- and CYC-ir were co-expressed in two pairs of dorsolateral neurons of the protocerebrum, suggesting that these are the circadian neurons that also express melatonin-, NAT- and HIOMT-ir. The results suggest that a melatonin pathway is present in the circadian neurons. Melatonin receptor (MT2 or MEL-1B-R)-ir in PTTH-ir neurons juxtaposing clock neurons suggests that melatonin gates PTTH release. RIA showed a melatonin rhythm with a peak four hours after lights off in adult brain both under LD16:8 (LD) and LD12:12 (SD), and both the peak and the baseline levels were higher under LD than SD, suggesting a photoperiodic influence. When pupae in diapause were exposed to 10 cycles of LD, or stored at 4 °C for 4 months under constant darkness, an increase of NAT activity was observed when PTTH released ecdysone. DNA sequence upstream of nat contained E-boxes to which CYC/CLK could bind, and nat transcription was turned off by clk or cyc dsRNA. dsRNA(NAT) caused dysfunction of photoperiodism. dsRNA(PER) upregulated nat transcription as anticipated, based on findings in the Drosophila melanogaster circadian system. Transcription of nat, cyc and clk peaked at ZT12. RIA showed that dsRNA(NAT) decreased melatonin while dsRNA(PER) increased melatonin. Thus nat, a clock controlled gene, is the critical link between the circadian clock and endocrine switch. MT-binding may release PTTH, resulting in termination of diapause. This study thus examined all of the basic functional units from the clock: a photoperiodic counter as an accumulator of mRNA(NAT), to endocrine switch for photoperiodism in A. pernyi showing this system is self-complete without additional device especially for photoperiodism.

  10. N-acetyltransferase (nat is a critical conjunct of photoperiodism between the circadian system and endocrine axis in Antheraea pernyi.

    Directory of Open Access Journals (Sweden)

    Ahmed A M Mohamed

    Full Text Available Since its discovery in 1923, the biology of photoperiodism remains a mystery in many ways. We sought the link connecting the circadian system to an endocrine switch, using Antheraea pernyi. PER-, CLK- and CYC-ir were co-expressed in two pairs of dorsolateral neurons of the protocerebrum, suggesting that these are the circadian neurons that also express melatonin-, NAT- and HIOMT-ir. The results suggest that a melatonin pathway is present in the circadian neurons. Melatonin receptor (MT2 or MEL-1B-R-ir in PTTH-ir neurons juxtaposing clock neurons suggests that melatonin gates PTTH release. RIA showed a melatonin rhythm with a peak four hours after lights off in adult brain both under LD16:8 (LD and LD12:12 (SD, and both the peak and the baseline levels were higher under LD than SD, suggesting a photoperiodic influence. When pupae in diapause were exposed to 10 cycles of LD, or stored at 4 °C for 4 months under constant darkness, an increase of NAT activity was observed when PTTH released ecdysone. DNA sequence upstream of nat contained E-boxes to which CYC/CLK could bind, and nat transcription was turned off by clk or cyc dsRNA. dsRNA(NAT caused dysfunction of photoperiodism. dsRNA(PER upregulated nat transcription as anticipated, based on findings in the Drosophila melanogaster circadian system. Transcription of nat, cyc and clk peaked at ZT12. RIA showed that dsRNA(NAT decreased melatonin while dsRNA(PER increased melatonin. Thus nat, a clock controlled gene, is the critical link between the circadian clock and endocrine switch. MT-binding may release PTTH, resulting in termination of diapause. This study thus examined all of the basic functional units from the clock: a photoperiodic counter as an accumulator of mRNA(NAT, to endocrine switch for photoperiodism in A. pernyi showing this system is self-complete without additional device especially for photoperiodism.

  11. Mild Conditions for Deuteration of Primary and Secondary Arylamines for the Synthesis of Deuterated Optoelectronic Organic Molecules

    Directory of Open Access Journals (Sweden)

    Anwen M. Krause-Heuer

    2014-11-01

    Full Text Available Deuterated arylamines demonstrate great potential for use in optoelectronic devices, but their widespread utility requires a method for large-scale synthesis. The incorporation of these deuterated materials into optoelectronic devices also provides the opportunity for studies of the functioning device using neutron reflectometry based on the difference in the scattering length density between protonated and deuterated compounds. Here we report mild deuteration conditions utilising standard laboratory glassware for the deuteration of: diphenylamine, N-phenylnaphthylamine, N-phenyl-o-phenylenediamine and 1-naphthylamine (via H/D exchange in D2O at 80 °C, catalysed by Pt/C and Pd/C. These conditions were not successful in the deuteration of triphenylamine or N,N-dimethylaniline, suggesting that these mild conditions are not suitable for the deuteration of tertiary arylamines, but are likely to be applicable for the deuteration of other primary and secondary arylamines. The deuterated arylamines can then be used for synthesis of larger organic molecules or polymers with optoelectronic applications.

  12. Mild conditions for deuteration of primary and secondary arylamines for the synthesis of deuterated optoelectronic organic molecules.

    Science.gov (United States)

    Krause-Heuer, Anwen M; Yepuri, Nageshwar R; Darwish, Tamim A; Holden, Peter J

    2014-11-13

    Deuterated arylamines demonstrate great potential for use in optoelectronic devices, but their widespread utility requires a method for large-scale synthesis. The incorporation of these deuterated materials into optoelectronic devices also provides the opportunity for studies of the functioning device using neutron reflectometry based on the difference in the scattering length density between protonated and deuterated compounds. Here we report mild deuteration conditions utilising standard laboratory glassware for the deuteration of: diphenylamine, N-phenylnaphthylamine, N-phenyl-o-phenylenediamine and 1-naphthylamine (via H/D exchange in D2O at 80 °C, catalysed by Pt/C and Pd/C). These conditions were not successful in the deuteration of triphenylamine or N,N-dimethylaniline, suggesting that these mild conditions are not suitable for the deuteration of tertiary arylamines, but are likely to be applicable for the deuteration of other primary and secondary arylamines. The deuterated arylamines can then be used for synthesis of larger organic molecules or polymers with optoelectronic applications.

  13. Pharmacogenomics, biochemistry, toxicology, microbiology and cancer research in one go.

    Science.gov (United States)

    Rodrigues-Lima, Fernando; Dairou, Julien; Laurieri, Nicola; Busi, Florent; Dupret, Jean-Marie

    2011-08-01

    Arylamine N-acetyltransferases (NATs) are phase II xenobiotic metabolizing enzymes playing a key role in the detoxification and metabolic activation of aromatic amine xenobiotics. The triennial International NAT Workshop has been an important academic meeting where developments in the study of NATs and aromatic amine metabolism have been presented. The 2010 Workshop took place in University Paris Diderot Paris, France. Topics included: structures and functions of eukaryotic and prokaryotic NATs, gene regulation and expression of human NATs, polymorphisms and their effects, arylamine metabolism and toxicity. Nomenclature issues were also discussed.

  14. 以芳香胺玻璃为载体的固定化的胆固醇脂酶和胆固醇氧化酶%Cholesterol Esterase and Cholesterol Oxidase Immobilized onto Arylamine Glass Beads

    Institute of Scientific and Technical Information of China (English)

    VoMalik; S.Singh; 等

    2002-01-01

    Cholesterol esterase (Cease) from bovine pancreas and cholesterol oxidasc (COD) from Bravibacterium recombinant type have been innobilized individually and co-immobilized onto arylamine glass (pore diameter 55nm) through the process of diazotization. Cease and COD retained 92.65% and 85.54% of the initial activity with conjugation yields of 7.2 mg/g and 8.3mg/g support respectively when imnobilized individually on arylamine glass beads, but retained 89.58% of the initial activity with a conjugation yield of 2.9 mg/g support when co-immobilized on the same support. The effects of pH, temperature, time of incubation, substrate concentration, serum inorganic salts & metabolites, thermal stability, storage stability in cold and reusability on the immobilized enzymes were studied and compared with those of free enzymes. The analytic use of both individually immobilized and co-immobilized enzymes in discrete analysis of total and free cholesterol in serum is demonstrated.

  15. Synthesis and characterization of arylamine derivatives of rauwolscine as molecular probes for alpha 2-adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Lanier, S.M.; Graham, R.M.; Hess, H.J.; Grodski, A.; Repaske, M.G.; Nunnari, J.M.; Limbird, L.E.; Homcy, C.J.

    1987-06-01

    The selective alpha 2-adrenergic receptor antagonist rauwolscine was structurally modified to yield a series of arylamine carboxamide derivatives, which were investigated as potential molecular probes for the localization and structural characterization of alpha 2-adrenergic receptors. The arylamine carboxamides differ in the number of carbon atoms separating the reactive phenyl moiety from the fused ring structure of the parent compound, rauwolscine carboxylate. Competitive inhibition studies with (/sup 3/H)rauwolscine in rat kidney membranes indicate that the affinity for the carboxamide derivatives is inversely related to the length of the carbon spacer arm with rauwolscine 4-aminophenyl carboxamide exhibiting the highest affinity (Kd = 2.3 +/- 0.2 nM). Radioiodination of rau-AMPC yields a ligand, /sup 125/I-rau-AMPC, which binds to rat kidney alpha 2-adrenergic receptors with high affinity, as determined by both kinetic analysis (Kd = k2/k1 = 0.016 min-1/2.1 X 10(7) M-1 min-1 = 0.76 nM) and equilibrium binding studies (Kd = 0.78 +/- 0.16 nM). /sup 125/I-rau-AMPC was quantitatively converted to the photolabile arylazide derivative 17 alpha-hydroxy-20 alpha-yohimban-16 beta-(N-4-azido-3-(/sup 125/I)iodophenyl) carboxamide (/sup 125/I-rau-AZPC). In a partially purified receptor preparation from porcine brain, this compound photolabels a major (Mr = 62,000) peptide. The labeling of this peptide is inhibited by adrenergic agonists and antagonists with a rank order of potency consistent with an alpha 2-adrenergic receptor binding site. Both /sup 125/I-rau-AMPC and the photolabile arylazide derivative, /sup 125/I-rau-AZPC, should prove useful as molecular probes for the structural and biochemical characterization of alpha 2-adrenergic receptors.

  16. Proteomic profile of aminoglutethimide-induced apoptosis in HL-60 cells: Role of myeloperoxidase and arylamine free radicals.

    Science.gov (United States)

    Khan, Saifur R; Baghdasarian, Argishti; Nagar, Prarthna H; Fahlman, Richard; Jurasz, Paul; Michail, Karim; Aljuhani, Naif; Siraki, Arno G

    2015-09-01

    In this study, the cellular effects resulting from the metabolism of aminoglutethimide by myeloperoxidase were investigated. Human promyelocytic leukemia (HL-60) cells were treated with aminoglutethimide (AG), an arylamine drug that has a risk of adverse drug reactions, including drug-induced agranulocytosis. HL-60 cells contain abundant amounts of myeloperoxidase (MPO), a hemoprotein, which catalyzes one-electron oxidation of arylamines using H2O2 as a cofactor. Previous studies have shown that arylamine metabolism by MPO results in protein radical formation. The purpose of this study was to determine if pathways associated with a toxic response could be determined from conditions that produced protein radicals. Conditions for AG-induced protein radical formation (with minimal cytotoxicity) were optimized, and these conditions were used to carry out proteomic studies. We identified 43 proteins that were changed significantly upon AG treatment among which 18 were up-regulated and 25 were down-regulated. The quantitative proteomic data showed that AG peroxidative metabolism led to the down-regulation of critical anti-apoptotic proteins responsible for inhibiting the release of pro-apoptotic factors from the mitochondria as well as cytoskeletal proteins such as nuclear lamina. This overall pro-apoptotic response was confirmed with flow cytometry which demonstrated apoptosis to be the main mode of cell death, and this was attenuated by MPO inhibition. This response correlated with the intensity of AG-induced protein radical formation in HL-60 cells, which may play a role in cell death signaling mechanisms.

  17. Nano MgBi₂O₄: A Novel Green Catalyst for the One-step Cascade Condensation of Arylamines, Acetone and Isatins in Water

    Indian Academy of Sciences (India)

    KOBRA NIKOOFAR; ZAHRA KHADEMI; MARYAM HAGHIGHI

    2016-11-01

    Nano-size MgBi₂O₄ has been synthesized for the first time via a simple co-precipitation method using the surfactant N-cetyl-N, N,N-trimethylammonium bromide (CTAB). Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray powder diffraction (XRD) techniques were employed to characterize the nano-catalyst. Additionally, the reactivity of the prepared nanoparticles was investigated in the synthesis of 1'-aryl-2'-(2-oxoindolin-3-yl)spiro[indoline-3,5'-pyrroline]-2,3'-diones in a one-pot, one-step and pseudo four-component condensation of arylamine, acetone, and isatins at 50◦C in water. Five new compounds were synthesized and identified. This procedure has various advantages such as, short reaction times, mild eco-friendly conditions and excellent yields to prepare a novel class of heteroaromatic compounds. MgBi₂O₄ possess superior qualities such as easy and economic preparation procedure and handling, stability, and non-toxicity. Its reusability has also been examined upto 4 runs without activity loss.

  18. Low melatonin production by suppression of either serotonin N-acetyltransferase or N-acetylserotonin methyltransferase in rice causes seedling growth retardation with yield penalty, abiotic stress susceptibility, and enhanced coleoptile growth under anoxic conditions.

    Science.gov (United States)

    Byeon, Yeong; Back, Kyoungwhan

    2016-04-01

    Serotonin N-acetyltransferase (SNAT) and N-acetylserotonin methyltransferase (ASMT) are the last two key enzymes for melatonin biosynthesis in living organisms. In this study, we demonstrated that transgenic rice (Oryza sativa L.) plants, in which expression of either endogenous SNAT or ASMT was suppressed, had reduced melatonin synthesis, confirming that both SNAT and ASMT are functionally involved in melatonin synthesis. The melatonin-deficient SNAT rice had retarded seedling growth, which was partially restored by exogenous melatonin application, suggesting melatonin's role in seedling growth. In addition, the plants were more sensitive to various abiotic stresses, including salt and cold, compared with the wild type. Melatonin-deficient SNAT rice had increased coleoptile growth under anoxic conditions, indicating that melatonin also inversely regulates plant growth under anaerobic conditions with the concomitant high expression of alcohol dehydrogenase genes. Similarly, the melatonin-deficient ASMT rice exhibited accelerated senescence in detached flag leaves, as well as significantly reduced yield. These loss-of-function studies on the melatonin biosynthetic genes confirmed most previous pharmacological reports that melatonin not only promotes plant growth but also mitigates various abiotic stresses.

  19. FeCl2-promoted cleavage of the unactivated C-C bond of alkylarenes and polystyrene: direct synthesis of arylamines.

    Science.gov (United States)

    Qin, Chong; Shen, Tao; Tang, Conghui; Jiao, Ning

    2012-07-09

    Ironing it out: an efficient and convenient nitrogenation strategy involving C-C bond cleavage for the straightforward synthesis of versatile arylamines is presented. Various alkyl azides and alkylarenes, including the common industrial by-product cumene, react using this protocol. Moreover, this method provides a potential strategy for the degradation of polystyrene.

  20. Effect of dark exposure in the middle of the day on Period1, Period2, and arylalkylamine N-acetyltransferase mRNA levels in the rat suprachiasmatic nucleus and pineal gland.

    Science.gov (United States)

    Fukuhara, Chiaki

    2004-11-04

    The suprachiasmatic nucleus (SCN) of the mammalian hypothalamus contains a central circadian pacemaker, which adjusts circadian rhythms within the body to environmental light-dark cycles. It has been shown that dark exposure in the day causes phase shifts in circadian rhythms, but it does not induce changes in the melatonin levels in the pineal gland. In this study, we examined the effect of dark exposure on two "circadian clock" genes Period1 and Period2 mRNA levels in the rat SCN, and on Period1, Period2, and arylalkylamine N-acetyltransferase (Aa-Nat, the rate-limiting enzyme in melatonin synthesis) gene expression in the pineal gland. Period1 and Period2 mRNA levels were significantly decreased in the SCN after 0.5 and 2 h, respectively, therefore suggesting that changes in those mRNA levels may be the part of the mechanisms of dark-induced phase shifts. Period1 and Aa-Nat mRNA levels in the pineal gland were not affected by darkness, but Period2 was moderately affected. Since Period1 and Aa-Nat mRNA levels in the pineal gland did not respond to dark stimulation, we further examined whether the pineal gland itself is capable of responding to adrenergic stimulation at this time of the day. Isoproterenol significantly induced Period1 and Aa-Nat mRNA levels; however, it did not affect Period2. Although previous studies have reported that during the day the SCN "gates" the dark information reaching the pineal, our data demonstrate that dark information may reach the pineal during the daytime.

  1. Unravelling the structural-electronic impact of arylamine electron-donating antennas on the performances of efficient ruthenium sensitizers for dye-sensitized solar cells

    Science.gov (United States)

    Chen, Wang-Chao; Kong, Fan-Tai; Ghadari, Rahim; Li, Zhao-Qian; Guo, Fu-Ling; Liu, Xue-Peng; Huang, Yang; Yu, Ting; Hayat, Tasawar; Dai, Song-Yuan

    2017-04-01

    We report a systematic research to understand the structural-electronic impact of the arylamine electron-donating antennas on the performances of the ruthenium complexes for dye-sensitized solar cells. Three ruthenium complexes functionalized with different arylamine electron-donating antennas (N,N-diethyl-aniline in RC-31, julolidine in RC-32 and N,N-dibenzyl-aniline in RC-36) are designed and synthesized. The photoelectric properties of RC dyes exhibit apparent discrepancy, which are ascribed to different structural nature and electronic delocalization ability of these arylamine electron-donating system. In conjunction with TiO2 microspheres photoanode and a typical coadsorbent DPA, the devices sensitized by RC-36 achieve the best conversion efficiency of 10.23%. The UV-Vis absorption, electrochemical measurement, incident photon-to-current conversion efficiency and transient absorption spectra confirm that the excellent performance of RC-36 is induced by synergistically structural-electronic impacts from enhanced absorption capacity and well-tuned electronic characteristics. These observations provide valuable insights into the molecular engineering methodology based on fine tuning structural-electronic impact of electron-donating antenna in efficient ruthenium sensitizers.

  2. RELATIONSHIP BETWEEN GENETIC POLYMORPHISMS OF N- ACETYLTRANSFERASE 2 AND SUSCEPTIBILITY OF BREAST CANCER IN SHANDONG DISTRICT%山东地区NAT2基因多态性与乳腺癌易感性的研究

    Institute of Scientific and Technical Information of China (English)

    王萍玉; 谢书阳; 张超; 高宗华

    2011-01-01

    [目的]研究NAT2基因多态性与乳腺癌易感性的关系.[方法]采用1:1配对病例-对照研究,对山东地区100例乳腺癌患者和100例健康对照者采用聚合酶链反应-限制性片段长度多态性分析(PCR- RFLP),检测NAT2基因多态性,分析NAT2基因多态性与乳腺癌易感性之间的关系.[结果]携带NAT2/5B等位基因者患乳腺癌 危险性增加(OR=2.38, 95%CI=1.54~3.67);幔基因型者患乳腺癌的危险性是快基因型者2.28倍(OR=2.28,95%CI=1.12~4.63);是中间基因型者2.14倍(OR=2.14,95%CI=1.08~4.24);慢型乙酰化患乳腺癌的危险性是快型乙酰化的2.11倍(OR=2.11, 95%CI=1.15-3.88).[结论]NAT2基因多态性在乳腺癌的遗传发病机制中起重要作用,携带NAT2/5B等位基因、慢基因型及慢型乙酰化能增加患乳腺癌的易感性.%[Objective] To evaluate the possible relationship between N-acetyltransferase 2 (NAT2) polymorphisms and breast cancer. [Methods] In the 1: 1 matched case-control study, NAT2 genotypes were determined by PCR-RFLP method in 100 patients with breast cancer and 100 healthy controls. The possible relationship between NAT2 polymorphisms and lung cancer risk was analyzed. [Results] NAT2*5B allele was associated with an increased risk of breast cancer (odds ratio (OR) 2.38 (95% confidence interval (95%Cl) 1.54-3.67; slow genotype was 2.28 times to rapid genotype (OR = 2.28, 95%CI= 1.12-4.63) and 2.14 times to intermediate genotype (OR - 2.14, 95%C/=1.08-4.24); and NAT2 slow acetylates increased risk of breast cancer (OR = 2.11, 95%C/ = 1.15-3.88). [Conclusion] These findings suggest that NAT2 genetic polymorphism may be associated with breast cancer susceptibility. People with NAT2*5B allele or NAT2 slow genotype or NAT2 slow acetylates have higher breast cancer risk.

  3. Power Conversion Efficiency of Arylamine Organic Dyes for Dye-Sensitized Solar Cells (DSSCs Explicit to Cobalt Electrolyte: Understanding the Structural Attributes Using a Direct QSPR Approach

    Directory of Open Access Journals (Sweden)

    Supratik Kar

    2016-12-01

    Full Text Available Post silicon solar cell era involves light-absorbing dyes for dye-sensitized solar systems (DSSCs. Therefore, there is great interest in the design of competent organic dyes for DSSCs with high power conversion efficiency (PCE to bypass some of the disadvantages of silicon-based solar cell technologies, such as high cost, heavy weight, limited silicon resources, and production methods that lead to high environmental pollution. The DSSC has the unique feature of a distance-dependent electron transfer step. This depends on the relative position of the sensitized organic dye in the metal oxide composite system. In the present work, we developed quantitative structure-property relationship (QSPR models to set up the quantitative relationship between the overall PCE and quantum chemical molecular descriptors. They were calculated from density functional theory (DFT and time-dependent DFT (TD-DFT methods as well as from DRAGON software. This allows for understanding the basic electron transfer mechanism along with the structural attributes of arylamine-organic dye sensitizers for the DSSCs explicit to cobalt electrolyte. The identified properties and structural fragments are particularly valuable for guiding time-saving synthetic efforts for development of efficient arylamine organic dyes with improved power conversion efficiency.

  4. 龙葵碱对人肝癌HepG2细胞N-乙酰基转移酶活性的影响%Effect of solanine on N-acetyltransferase activity in HepG2 cell

    Institute of Scientific and Technical Information of China (English)

    高世勇; 季字彬

    2008-01-01

    目的 探讨龙葵碱对HepG2细胞Ⅳ-乙酰基转移酶(NAT)活性的影响.方法 采用HPLC方法,以2-氨基芴(2-AF)为底物,以2-AF被NAT乙酰化为2-乙酰氨基芴(2-AAF)的量来反应NAT的活性.结果 龙葵碱能显著降低HepG2完整细胞NAT的活性;龙葵碱能够降低HepG2细胞质内NAT的活性,作用具有剂量依赖性.结论 龙葵碱通过抑制HepG2细胞NAT的活性发挥细胞毒作用.

  5. 大鼠松果体Clock基因和芳烷脘N-乙酰基转移酶基因的昼夜节律性表达及光照影响%Circadian rhythms and light responses of clock gene and arylalkylamine N-acetyltransferase gene expressions in the pineal gland of rats

    Institute of Scientific and Technical Information of China (English)

    王国卿; 杜玉珍; 童建

    2005-01-01

    探讨12 h光照、12 h黑暗交替(12 h-light:12 h-dark cycle,LD)及持续黑暗(constant darkness,DD)光制下松果体Clock基因和芳烷脘N-乙酰基转移酶基因(arylalkylamine N-acetyltransferase gene,NAT)是否存在昼夜节律性表达及其光反应变化.Sprague-Dawley大鼠在LD和DD光制下分别被饲养4周(n=36)和8周(n=36)后,在一昼夜内每隔4 h采集一组松果体组织(n=6),提取总RNA,用竞争性定量RT-PCR测定不同昼夜时点样品中Clock及NAT基因的mRNA相对表达量,通过余弦法和ClockLab软件获取节律参数,并经振幅检验是否存在昼夜节律.结果如下:(1)在DD或LD光制下,松果体Clock和NAT基因mRNA的表达均呈现夜高昼低的节律性振荡(P<0.05).(2)与DD光制下比较,LD光制下松果体Clock和NAT基因的表达振幅及峰值相的mRNA水平均降低(P<0.05).(3)在DD或LD光制下,Clock和NAT基因之间显示相似的节律性表达(P>0.05).结果表明,Clock和NAT基因在松果体中存在同步的内源性昼夜节律表达,光照作用可使其表达下调.

  6. Influences of Hypoxic-ischemic Brain Damage on Pineal Arylalkylamine-N-acetyltransferase mRNA Expression and Plasma Melatonin Level in Neonatal Rats%缺氧缺血对新生大鼠松果体芳香烷基胺-N-乙酰基转移酶

    Institute of Scientific and Technical Information of China (English)

    丁欣; 姜善雨; 冯星; 何军; 孙斌; 朱雪明

    2011-01-01

    Objective To elucidate the influences of hypoxic-ischemic brain damage (HIBD) on pineal function of melatonin synthesis and explore the possible significance of pineal function alterations in HIBD.Methods Sixty seven-day-old rats were randomly divided into 2 groups: the HIBD group and sham-operated group.Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to measure the melatonin-synthetase-arylalkylamine-N-acetyltransferase (AANAT) mRNA expressions in pineal gland.Radioimmunoassay (RIA) was used to measure the plasma melatonin levels.Results ( 1 ) The AANAT mRNA expression 6 h, 12 h, 24 h after HIBD were lower than those in the corresponding sham-operated groups( P <0.05 or 0.01 ) ,and no significant difference was found among different time points in the sham-operated groups; (2) The plasma melatonin levels 12 h, 24 h after HIBD were lower than those in the corresponding sham-operated groups.The melatonin levels at different time points in the sham-operated group were similar.Conclusions Pineal melatonin-synthesis is impaired on early stage of HIBD.Alternation of the protective process of endogenous MLT might be involved in pathogenic mechanism of early HIBD.%目的 了解缺氧缺血性脑损伤(HIBD)对松果体芳香烷基胺-N-乙酰基转移酶(AANAT)mRNA表达和血浆褪黑素(MLT)含量的影响,探讨松果体功能改变在HIBD中的意义.方法 选取7日龄SD大鼠60只随机分成HIBD模型组和假手术组.HIBD模型组按改良Levine法建立,然后用半定量逆转录聚合酶链反应(RT-PCR)和放免技术分别测定并比较两组缺氧缺血后0 h、6 h、12 h、24h、48 h松果体中AANAT mRNA的表达水平及血浆MLT的浓度.结果 (1)松果体中AANAT mRNA的表达在HIBD后6 h、12 h、24 h低于对应假手术组(P<0.05或<0.01);假手术组各时点之间AANAT mRNA的表达水平无明显变化(P>0.05).(2)血浆MLT浓度在HIBD后12 h、24 h均低于对应假手术组(P<0.01);假手术组

  7. The role of para-aminophenol in acetaminophen-induced methemoglobinemia in dogs and cats.

    Science.gov (United States)

    McConkey, S E; Grant, D M; Cribb, A E

    2009-12-01

    Acetaminophen (APAP) overdose in most species is associated with hepatotoxicity because of the metabolite N-acetyl-p-benzoquinoneimine (NAPQI). In dogs and cats, APAP overdose primarily causes methemoglobinemia and hemolysis. Although NAPQI has been proposed as the responsible intermediate in dogs and cats, it lacks chemical or pharmacokinetic characteristics that favor methemoglobin formation. We hypothesized that para-aminophenol (PAP) rather than NAPQI induces methemoglobinemia and that deficient arylamine N-acetyltransferase (NAT) activity in dogs and cats contributes to this species-dependent methemoglobinemia. Erythrocytes from dogs, cats, mice, and rats were exposed in vitro to APAP, NAPQI, and PAP. Only PAP induced methemoglobin and it induced more methemoglobin formation in dog and cat than rat and mouse erythrocytes. PAP also induced more methemoglobin in erythrocytes from Nat1/Nat2 knockout mice than wildtype (WT) mouse erythrocytes (P dog and cat erythrocytes (P dogs and cats contributes to this species-dependent toxicity.

  8. Trifluoroacetic acid in 2,2,2-trifluoroethanol facilitates S(N)Ar reactions of heterocycles with arylamines.

    Science.gov (United States)

    Carbain, Benoit; Coxon, Christopher R; Lebraud, Honorine; Elliott, Kristopher J; Matheson, Christopher J; Meschini, Elisa; Roberts, Amy R; Turner, David M; Wong, Christopher; Cano, Celine; Griffin, Roger J; Hardcastle, Ian R; Golding, Bernard T

    2014-02-17

    Small-molecule drug discovery requires reliable synthetic methods for attaching amino compounds to heterocyclic scaffolds. Trifluoroacetic acid-2,2,2-trifluoroethanol (TFA-TFE) is as an effective combination for achieving SN Ar reactions between anilines and heterocycles (e.g., purines and pyrimidines) substituted with a leaving group (fluoro-, chloro-, bromo- or alkylsulfonyl). This method provides a variety of compounds containing a "kinase-privileged fragment" associated with potent inhibition of kinases. TFE is an advantageous solvent because of its low nucleophilicity, ease of removal and ability to solubilise polar substrates. Furthermore, TFE may assist the breakdown of the Meisenheimer-Jackson intermediate by solvating the leaving group. TFA is a necessary and effective acidic catalyst, which activates the heterocycle by N-protonation without deactivating the aniline by conversion into an anilinium species. The TFA-TFE methodology is compatible with a variety of functional groups and complements organometallic alternatives, which are often disadvantageous because of the expense of reagents, the frequent need to explore diverse sets of reaction conditions, and problems with product purification. In contrast, product isolation from TFA-TFE reactions is straightforward: evaporation of the reaction mixture, basification and chromatography affords analytically pure material. A total of 45 examples are described with seven discrete heterocyclic scaffolds and 2-, 3- and 4-substituted anilines giving product yields that are normally in the range 50-90 %. Reactions can be performed with either conventional heating or microwave irradiation, with the latter often giving improved yields.

  9. GENETIC POLYMORPHISMS IN HUMAN LIVER PHENOL SULFOTRANSFERASES INVOLVED IN THE BIOACTIVATION OF N-HYDROXY DERIVATIVES OF CARCINOGENIC ARYLAMINES AND HETEROCYCLIC AMINES. (R825280)

    Science.gov (United States)

    AbstractThree related forms of phenol sulfotransferase (PSULT), thermostable ST1A2 (SULT1A2hum) and ST1A3 (SULT1A1hum) and a thermolabile TL-PST (SULT1A3hum), are known to exist in human livers. Thermostable forms, whose activities are polymorphically distributed, hav...

  10. Structural Analysis of a Putative Aminoglycoside N-Acetyltransferase from Bacillus anthracis

    Energy Technology Data Exchange (ETDEWEB)

    Klimecka, Maria M.; Chruszcz, Maksymilian; Font, Jose; Skarina, Tatiana; Shumilin, Igor; Onopryienko, Olena; Porebski, Przemyslaw J.; Cymborowski, Marcin; Zimmerman, Matthew D.; Hasseman, Jeremy; Glomski, Ian J.; Lebioda, Lukasz; Savchenko, Alexei; Edwards, Aled; Minor, Wladek (SC); (Toronto); (UV)

    2012-02-15

    For the last decade, worldwide efforts for the treatment of anthrax infection have focused on developing effective vaccines. Patients that are already infected are still treated traditionally using different types of standard antimicrobial agents. The most popular are antibiotics such as tetracyclines and fluoroquinolones. While aminoglycosides appear to be less effective antimicrobial agents than other antibiotics, synthetic aminoglycosides have been shown to act as potent inhibitors of anthrax lethal factor and may have potential application as antitoxins. Here, we present a structural analysis of the BA2930 protein, a putative aminoglycoside acetyltransferase, which may be a component of the bacterium's aminoglycoside resistance mechanism. The determined structures revealed details of a fold characteristic only for one other protein structure in the Protein Data Bank, namely, YokD from Bacillus subtilis. Both BA2930 and YokD are members of the Antibiotic-NAT superfamily (PF02522). Sequential and structural analyses showed that residues conserved throughout the Antibiotic-NAT superfamily are responsible for the binding of the cofactor acetyl coenzyme A. The interaction of BA2930 with cofactors was characterized by both crystallographic and binding studies.

  11. N-acetyltransferase 2 polymorphisms and risk of esophageal cancer in a Chinese population.

    Directory of Open Access Journals (Sweden)

    Liming Wang

    Full Text Available Esophageal cancer was the fifth most commonly diagnosed cancer and the fourth leading cause of cancer-related death in China in 2009. Genetic factors might play an important role in the carcinogenesis of esophageal squamous cell carcinoma (ESCC. We conducted a hospital-based case-control study to evaluate ten NAT2 tagging single nucleotide polymorphisms (SNPs on the risk of ESCC. Six hundred and twenty-nine ESCC cases and 686 controls were recruited. Their genotypes were determined using the ligation detection reaction method. In the single locus analyses, there was a borderline statistically significant difference in genotype frequencies of NAT2 rs1565684 T>C SNP between the cases and the controls (p = 0.057. The NAT2 rs1565684 CC genotype was associated with a borderline significantly increased risk for ESCC (CC vs. TT: adjusted OR = 1.77, 95% CI = 0.97-3.21, p = 0.063 and CC vs. TT/TC: adjusted OR = 1.68, 95% CI = 0.93-3.04, p = 0.085. The association was evident among older patients and patients who never drunk. After the Bonferroni correction, in all comparison models, NAT2 rs1565684 T>C SNP was not associated with ESCC risk (p>0.05. For the other nine NAT2 SNPs, after Bonferroni correction, in all comparison models, the nine SNPs were also not associated with ESCC risk (p>0.05. Thus, nine NAT2 tagging SNPs were not associated with risk of ESCC. NAT2 rs1565684 T>C SNP might play a slight role in ESCC etiology. Additional, larger studies and tissue-specific biological characterization are required to confirm the current findings.

  12. Pt/PIC催化还原芳香硝基化合物制备芳胺%Pt/PIC catalyzed hydrogenation of aromatic nitro compounds to arylamine

    Institute of Scientific and Technical Information of China (English)

    张渊; 张瑞; 黄军; 朱福和

    2012-01-01

    制备了一种多孔离子型高聚物(简称离聚物PIC),利用扫描电镜、透射电镜等一系列手段对离聚物PIC的形貌、结构进行表征,并制备负载型纳米铂催化剂(Pt/PIC)用于温和条件下芳胺(如对苯二胺、邻苯二胺、2-溴苯胺等)的合成实验中。实验表明:在1 atm H2条件下,该Pt/PIC催化剂对于芳香硝基化合物还原氢化反应具有高的催化活性和选择性,尤其是还原性基团如醛基、酮基、氰基,在氢化还原相应硝基芳基化合物过程中未受影响,且高产率得到相应芳胺。%A porous ionic copolymer(PIC) was prepared and characterized by SEM,BET,and TEM.The morphology and structure was investigated.And a supported Pt nano-catalyst(Pt/PIC) was prepared and used for the synthesis of anilines(such as p-phenylenediamine,o-diaminobenzene,2-Bromoaniline,et al.) under mild conditions.The study results showed that Pt/PIC catalyst was highly active and selective for the hydrogenation of nitro aromatic compounds under 1 atm H2.Reducible groups such as aldehyde,ketone and nitrile were not attacked during the hydrogenation of the corresponding nitro compounds,and the corresponding anilines were obtained with high yield.

  13. N-Acetylation of p-aminobenzoic acid and p-phenylenediamine in primary porcine urinary bladder epithelial cells and in the human urothelial cell line 5637.

    Science.gov (United States)

    Föllmann, Wolfram; Blaszkewicz, Meinolf; Behm, Claudia; Degen, Gisela H; Golka, Klaus

    2012-01-01

    N-Acetyltransferases (NAT) are important enzymes in the metabolism of certain carcinogenic arylamines, as N-acetylation decreases or prevents their bioactivation via N-hydroxylation. To study such processes in the bladder, cell culture models may be used, but metabolic competence needs to be characterized. This study focused on the N-acetylation capacity of two urothelial cell systems, using p-aminobenzoic acid (PABA) and the hair dye precursor p-phenylenediamine (PPD), two well-known substrates of the enzyme NAT1. The constitutive NAT1 activity was investigated using primary cultures of porcine urinary bladder epithelial cells (PUBEC) and in the human urothelial cell line 5637 to assess their suitability for further in vitro studies on PABA and PPD-induced toxicity. N-Acetylation of PABA and PPD was determined by high-performance liquid chromatography (HPLC) analysis in cytosols of the two cell systems upon incubation with various substrate levels for up to 60 min. The primary PUBEC revealed higher N-acetylation rates (2.5-fold for PABA, 5-fold for PPD) compared to the 5637 cell line, based on both PABA conversion to its acetylated metabolite and formation of mono- and diacetylated PPD. The urothelial cell systems may thus be useful as a tool for further studies on the N-acetylation of aromatic amines via NAT1.

  14. Antimicrobial Activity of UV-Induced Phenylamides from Rice Leaves

    Directory of Open Access Journals (Sweden)

    Hye Lin Park

    2014-11-01

    Full Text Available Rice produces a wide array of phytoalexins in response to pathogen attacks and UV-irradiation. Except for the flavonoid sakuranetin, most phytoalexins identified in rice are diterpenoid compounds. Analysis of phenolic-enriched fractions from UV-treated rice leaves showed that several phenolic compounds in addition to sakuranetin accumulated remarkably in rice leaves. We isolated two compounds from UV-treated rice leaves using silica gel column chromatography and preparative HPLC. The isolated phenolic compounds were identified as phenylamide compounds: N-trans-cinnamoyltryptamine and N-p-coumaroylserotonin. Expression analysis of biosynthetic genes demonstrated that genes for arylamine biosynthesis were upregulated by UV irradiation. This result suggested that phenylamide biosynthetic pathways are activated in rice leaves by UV treatment. To unravel the role of UV-induced phenylamides as phytoalexins, we examined their antimicrobial activity against rice fungal and bacterial pathogens. N-trans-Cinnamoyltryptamine inhibited the growth of rice brown spot fungus (Bipolaris oryzae. In addition to the known antifungal activity to the blast fungus, sakuranetin had antimicrobial activity toward B. oryzae and Rhizoctonia solani (rice sheath blight fungus. UV-induced phenylamides and sakuranetin also had antimicrobial activity against rice bacterial pathogens for grain rot (Burkholderia glumae, blight (Xanthomonas oryzae pv. oryzae and leaf streak (X. oryzae pv. oryzicola diseases. These findings suggested that the UV-induced phenylamides in rice are phytoalexins against a diverse array of pathogens.

  15. N-acetyltransferase 2 (NAT2 Gene Polymorphisms and the Effectiveness of Infertility Treatment in Patients with Peritoneal Endometriosis

    Directory of Open Access Journals (Sweden)

    Ekaterina D. Dubinskaya

    2014-03-01

    Full Text Available Today, infertility has become a global issue. WHO ranks it the fifth among the major diseases of those below 60 years, after alcoholism, depression, injuries and eyesight disorders. Numerous studies conducted on the problems of infertility in endometriosis still do not offer clear answers regarding the pathogenesis and mechanisms of this disease and its influences on fertility. According to the survey results, point mutations of the NAT2 gene (NAT2*5 and NAT2*6 have been identified in 75.6% of the patients with infertility problems and the peritoneal form of endometriosis, that create “slow” allelic variants, which exceed the average index in the population. The peculiarities of the NAT2 gene polymorphisms have been proven to be associated with the effectiveness of the infertility treatment of female patients with peritoneal endometriosis. In the group of non-pregnant patients, the presence of с.341Т>C, c.481C>T, c.590G>A and c.803A>G heterozygous point mutations are 73.2, 73.2, 5.4, and 62.5%, respectively. The significant difference in the comparison of the allelic polymorphism during the various stages of the endometriosis was not identified. At stage III-IV endometriosis the frequency of three and more point substitutions was significantly higher. NAT2 gene polymorphisms can find use as an additional criterion for predicting the effectiveness of the infertility treatment of patients with peritoneal endometriosis.

  16. MT1 receptor expression and AA-NAT activity in lymphatic tissue following melatonin administration in male golden hamster.

    Science.gov (United States)

    Vishwas, Dipanshu Kumar; Haldar, Chandana

    2014-09-01

    Exogenous melatonin as a marker of the chemical expression of darkness is playing a key role in the synchronization of circadian functions and seasonal biological rhythms. Our study was designed to elucidate whether melatonin treatment can modulate the melatonin synthesis via the rate limiting enzyme arylalkylamine-N-acetyltransferase (AA-NAT) in spleen, thymus and bone marrow thereby the proliferation rate of splenocytes, thymocytes and bone marrow mononuclear cells (BM-MNCs) of golden hamsters. The AA-NAT activity in different lymphoid tissue documented the synthesis of melatonin in those organs. Exogenous melatonin treatment to hamsters enhanced the AA-NAT activity in spleen and thymus along with an increase in the inflammatory response by DTH reactions that could be related to the increased level of interleukin-2 and IFN-γ by T lymphocytes in serum/culture medium, proliferation rate and expression of melatonin membrane receptor MT(1). Thus, the relevance of melatonin synthesis by lymphatic tissues might be maintaining surveillance and local defence responses.

  17. The effect of chronic morphine or methadone exposure and withdrawal on clock gene expression in the rat suprachiasmatic nucleus and AA-NAT activity in the pineal gland.

    Science.gov (United States)

    Pačesová, D; Novotný, J; Bendová, Z

    2016-07-18

    The circadian rhythms of many behavioral and physiological functions are regulated by the major circadian pacemaker in the suprachiasmatic nucleus. Long-term opiate addiction and drug withdrawal may affect circadian rhythmicity of various hormones or the sleep/activity pattern of many experimental subjects; however, limited research has been done on the long-term effects of sustained opiate administration on the intrinsic rhythmicity in the suprachiasmatic nucleus and pineal gland. Here we compared the effects of repeated daily treatment of rats with morphine or methadone and subsequent naloxone-precipitated withdrawal on the expression of the Per1, Per2, and Avp mRNAs in the suprachiasmatic nucleus and on arylalkylamine N-acetyltransferase activity in the pineal gland. We revealed that 10-day administration and withdrawal of both these drugs failed to affect clock genes and Avp expression in the SCN. Our results indicate that opioid-induced changes in behavioral and physiological rhythms originate in brain structures downstream of the suprachiasmatic nucleus regulatory output pathway. Furthermore, we observed that acute withdrawal from methadone markedly extended the period of high night AA-NAT activity in the pineal gland. This suggests that withdrawal from methadone, a widely used drug for the treatment of opioid dependence, may have stronger impact on melatonin synthesis than withdrawal from morphine.

  18. Lactoperoxidase-catalyzed activation of carcinogenic aromatic and heterocyclic amines.

    Science.gov (United States)

    Gorlewska-Roberts, Katarzyna M; Teitel, Candee H; Lay, Jackson O; Roberts, Dean W; Kadlubar, Fred F

    2004-12-01

    Lactoperoxidase, an enzyme secreted from the human mammary gland, plays a host defensive role through antimicrobial activity. It has been implicated in mutagenic and carcinogenic activation in the human mammary gland. The potential role of heterocyclic and aromatic amines in the etiology of breast cancer led us to examination of the lactoperoxidase-catalyzed activation of the most commonly studied arylamine carcinogens: 2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine (PhIP), benzidine, 4-aminobiphenyl (ABP), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). In vitro activation was performed with lactoperoxidase (partially purified from bovine milk or human milk) in the presence of hydrogen peroxide and calf thymus DNA. Products formed during enzymatic activation were monitored by HPLC with ultraviolet and radiometric detection. Two of these products were characterized as hydrazo and azo derivatives by means of mass spectrometry. The DNA binding level of 3H- and 14C-radiolabeled amines after peroxidase-catalyzed activation was dependent on the hydrogen peroxide concentration, and the highest levels of carcinogen binding to DNA were observed at 100 microM H2O2. Carcinogen activation and the level of binding to DNA were in the order of benzidine > ABP > IQ > MeIQx > PhIP. One of the ABP adducts was identified, and the level at which it is formed was estimated to be six adducts/10(5) nucleotides. The susceptibility of aromatic and heterocyclic amines for lactoperoxidase-catalyzed activation and the binding levels of activated products to DNA suggest a potential role of lactoperoxidase-catalyzed activation of carcinogens in the etiology of breast cancer.

  19. Overview on mechanisms of isoniazid action and resistance in Mycobacterium tuberculosis.

    Science.gov (United States)

    Unissa, Ameeruddin Nusrath; Subbian, Selvakumar; Hanna, Luke Elizabeth; Selvakumar, Nagamiah

    2016-11-01

    Isoniazid (INH) is one of the most active compounds used to treat tuberculosis (TB) worldwide. In addition, INH has been used as a prophylactic drug for individuals with latent Mycobacterium tuberculosis (MTB) infection to prevent reactivation of disease. Importantly, the definition of multidrug resistance (MDR) in TB is based on the resistance of MTB strains to INH and rifampicin (RIF). Despite its simple chemical structure, the mechanism of action of INH is very complex and involves several different concepts. Many pathways pertaining to macromolecular synthesis are affected, notably mycolic acid synthesis. The pro-drug INH is activated by catalase-peroxidase (KatG), and the active INH products are targeted by enzymes namely, enoyl acyl carrier protein (ACP) reductase (InhA) and beta-ketoacyl ACP synthase (KasA). In contrast, INH is inactivated by arylamine N-acetyltransferases (NATs). Consequently, the molecular mechanisms of INH resistance involve several genes in multiple biosynthetic networks and pathways. Mutation in the katG gene is the major cause for INH resistance, followed by inhA, ahpC, kasA, ndh, iniABC,fadE, furA, Rv1592c and Rv1772. The recent association of efflux genes with INH resistance has also gained considerable attention. Interestingly, substitutions have also been observed in nat, fabD, and accD recently in resistant isolates. Understanding the mechanisms operating behind INH action and resistance would enable better detection of INH resistance. This information would aid novel drug design strategies. Herein we review all mechanisms known to potentially contribute to the complexity of INH action and mechanisms of resistance in MTB, with insights into methods for detection of INH resistance as well as their limitations.

  20. Urinary mutagenicity, CYP1A2 and NAT2 activity in textile industry workers.

    Science.gov (United States)

    Fanlo, Ana; Sinuès, Blanca; Mayayo, Esteban; Bernal, Luisa; Soriano, Antonia; Martínez-Jarreta, Begoña; Martínez-Ballarín, Enrique

    2004-11-01

    The two major causes of bladder cancer have been recognised to be cigarette smoke and occupational exposure to arylamines. These compounds are present both in tobacco smoke and in the dyes used in textile production. Aromatic amines suffer oxidative metabolism via P450 cytochrome CYP1A2, and detoxification by the polymorphic NAT2. The aim of the present work was to assess the association between occupational-derived exposure to mutagens and CYP1A2 or NAT2 activity. This cross-sectional study included 117 textile workers exposed to dyes and 117 healthy controls. The urinary mutagenicity was determined in 24 h urine using TA98 Salmonella typhimurium strain with microsomal activation S9 (MIS9) or incubation with beta-glucuronidase (MIbeta). Urinary caffeine metabolite ratios: AFMU+1X+1U/17U, and AFMU/AFMU+1X+1U were calculated to assess CYP1A2 and NAT2 activities, respectively. The results show that workers present a strikingly higher urine mutagenicity than controls (p0.05) was compared, and the urinary mutagenicity was not significantly associated with the CYP1A2 activity marker (r=0.04 and r=-0.01 for MIS9 and MIbeta, respectively). This study clearly indicates the need for further protective policies to minimise exposure to the lowest feasible limit in order to avoid unnecessary risks.

  1. Adrenergic Activation of Melatonin Secretion in Ovine Pineal Explants in Short-Term Superfusion Culture Occurs via Protein Synthesis Independent and Dependent Phenomena

    Directory of Open Access Journals (Sweden)

    Bogdan Lewczuk

    2014-01-01

    Full Text Available The ovine pineal is generally considered as an interesting model for the study on adrenergic regulation of melatonin secretion due to some functional similarities with this gland in the human. The present investigations, performed in the superfusion culture of pineal explants, demonstrated that the norepinephrine-induced elevation of melatonin secretion in ovine pinealocytes comprised of two subsequent periods: a rapid increase phase and a slow increase phase. The first one included the quick rise in release of N-acetylserotonin and melatonin, occurring parallel to elevation of NE concentration in the medium surrounding explants. This rapid increase phase was not affected by inhibition of translation. The second, slow increase phase began after NE level had reached the maximum concentration in the culture medium and lasted about two hours. It was completely abolished by the treatment with translation inhibitors. The obtained results showed for the first time that the regulation of N-acetylserotonin synthesis in pinealocytes of some species like the sheep involves the on/off mechanism, which is completely independent of protein synthesis and works very fast. They provided strong evidence pointing to the need of revision of the current opinion that arylalkylamines N-acetyltransferase activity in pinealocytes is controlled exclusively by changes in enzyme abundance.

  2. Metabolic activation of aromatic amines and azo dyes.

    Science.gov (United States)

    Bartsch, H

    1981-01-01

    Aromatic amines, amides and nitro compounds are a class of chemicals that produce tumors in a wide variety of tissues in experimental animals, including liver, urinary bladder, forestomach, small intestine, Zymbal's gland, subcutaneous tissue or skin. In man, exposure to some aromatic amines is associated with tumours of the urinary bladder and carcinoma of the renal pelvis. Their biological activity as carcinogens or genotoxic agents is, in all the cases that have been studied in detail, dependent on metabolic activation in vivo, occurring by multiple pathways. Differences in these metabolic pathways may largely account for the differences in tissues and species susceptibilities to cancer induction. Carcinogenicity of aromatic amines or amides is dependent on their oxidation to N-hydroxy derivatives, whilst the carcinogenicity of aromatic nitro compounds is linked to their reduction to hydroxylamines. Further conversion of the N-hydroxylamine or N-hydroxyamide to reactive intermediates can occur in several ways, which include (i) esterification of the N-hydroxy group, (ii) non-enzymic protonation of the nitrogen of the hydroxylamine and (iii) oxidation to a free radical of arylhydroxamic acids. Following generation of such reactive electrophilic intermediates in tissues or cells, macromolecular binding has been observed to nucleic acids and proteins. In many cases, arylamidated and arylaminated products are formed with nucleic acid bases; in the case of the well-studied 2-acetylaminofluorene, nucleophilic atoms of guanine are the predominant site of reaction. Relatively little is known of the structure and biological consequences of DNA adducts formed from other aromatic amines, amides or nitro compounds; more research in these directions is warranted.

  3. The Effect of Yokukansan, a Traditional Herbal Preparation Used for the Behavioral and Psychological Symptoms of Dementia, on the Drug-Metabolizing Enzyme Activities in Healthy Male Volunteers.

    Science.gov (United States)

    Soraoka, Hiromi; Oniki, Kentaro; Matsuda, Kazuki; Ono, Tatsumasa; Taharazako, Kosuke; Uchiyashiki, Yoshihiro; Kamihashi, Ryoko; Kita, Ayana; Takashima, Ayaka; Nakagawa, Kazuko; Yasui-Furukori, Norio; Kadowaki, Daisuke; Miyata, Keishi; Saruwatari, Junji

    2016-01-01

    The concomitant use of herb and prescription medications is increasing globally. Herb-drug interactions are therefore a clinically important problem. Yokukansan (YKS), a Japanese traditional herbal medicine, is one of the most frequently used herbal medicines. It is effective for treating the behavioral and psychological symptoms of dementia. We investigated the potential effects of YKS on drug-metabolizing enzyme activities in humans. An open-label repeat-dose study was conducted in 26 healthy Japanese male volunteers (age: 22.7±2.3 years) with no history of smoking. An 8-h urine sample was collected after a 150-mg dose of caffeine and a 30-mg dose of dextromethorphan before and after the administration of YKS (2.5 g, twice a day for 1 week). The activities of cytochrome P450 (CYP) 1A2, CYP2D6, CYP3A, xanthine oxidase (XO) and N-acetyltransferase 2 (NAT2) were assessed based on the urinary metabolic indices of caffeine and dextromethorphan, and the urinary excretion ratio of 6β-hydroxycortisol to cortisol. There were no statistically significant differences in the activities of the examined enzymes before or after the 7-d administration of YKS. Although further studies assessing the influence of YKS on the pharmacokinetics and pharmacodynamics of the substrates of the drug-metabolizing enzymes are needed to verify the present results, YKS is unlikely that a pharmacokinetic interaction will occur with concomitantly administered medications that are predominantly metabolized by the CYP1A2, CYP2D6, CYP3A, XO and NAT2.

  4. Nocturnal activation of aurora C in rat pineal gland: its role in the norepinephrine-induced phosphorylation of histone H3 and gene expression.

    Science.gov (United States)

    Price, D M; Kanyo, R; Steinberg, N; Chik, C L; Ho, A K

    2009-05-01

    We have shown previously that Ser10 phosphorylation of histone H3 occurs in rat pinealocytes after stimulation with norepinephrine (NE) and that histone modifications such as acetylation appear to play an important role in pineal gene transcription. Here we report the nocturnal phosphorylation of a Ser10 histone H3 kinase, Aurora C, in the rat pineal gland. The time profile of this phosphorylation parallels the increase in the level of phospho-Ser10 histone H3. Studies with cultured pinealocytes indicate that Aurora C phosphorylation is induced by NE and this induction can be blocked by cotreatment with propranolol or KT5720, a protein kinase A inhibitor. Moreover, only treatment with dibutyryl cAMP, but not other kinase activators, mimics the effect of NE on Aurora C phosphorylation. These results indicate that Aurora C is phosphorylated primarily by a beta-adrenergic/protein kinase A-mediated mechanism. Treatment with an Aurora C inhibitor reduces the NE-induced histone H3 phosphorylation and suppresses the NE-stimulated induction of arylalkylamine N-acetyltransferase (AA-NAT), the rhythm-controlling enzyme of melatonin synthesis, and melatonin production. The effects of Aurora C inhibitors on adrenergic-induced genes in rat pinealocytes are gene specific: inhibitory for Aa-nat and inducible cAMP repressor but stimulatory for c-fos. Together our results support a role for the NE-stimulated phosphorylation of Aurora C and the subsequent remodeling of chromatin in NE-stimulated Aa-nat transcription. This phenomenon suggests that activation of this mitotic kinase can be induced by extracellular signals to participate in the transcriptional induction of a subset of genes in the rat pineal gland.

  5. Salmonella enterica Serovar Typhimurium blaPER-1-Carrying Plasmid pSTI1 Encodes an Extended-Spectrum Aminoglycoside 6′-N-Acetyltransferase of Type Ib

    OpenAIRE

    Casin, Isabelle; Hanau-Berçot, Beatrice; Podglajen, Isabelle; Vahaboglu, Haluk; Collatz, Ekkehard

    2003-01-01

    We have studied the aminoglycoside resistance gene, which confers high levels of resistance to both amikacin and gentamicin, that is carried by plasmid pSTI1 in the PER-1 β-lactamase-producing strain of Salmonella enterica serovar Typhimurium previously isolated in Turkey. This gene, called aac(6′)-Ib11, was found in a class 1 integron and codes for a protein of 188 amino acids, a fusion product between the N-terminal moiety (8 amino acids) of the signal peptide of the β-lactamase OXA-1 and t...

  6. Chromosomal aberrations in humans induced by urban air pollution: influence of DNA repair and polymorphisms of glutathione S-transferase M1 and N-acetyltransferase 2

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Norppa, H; Gamborg, M O

    1999-01-01

    We have studied the influence of individual susceptibility factors on the genotoxic effects of urban air pollution in 106 nonsmoking bus drivers and 101 postal workers in the Copenhagen metropolitan area. We used the frequency of chromosomal aberrations in peripheral blood lymphocytes...... that long-term exposure to urban air pollution (with traffic as the main contributor) induces chromosome damage in human somatic cells. Low DNA repair capacity and GSTM1 and NAT2 variants associated with reduced detoxification ability increase susceptibility to such damage. The effect of the GSTM1 genotype......, which was observed only in the bus drivers, appears to be associated with air pollution, whereas the NAT2 genotype effect, which affected all subjects, may influence the individual response to some other common exposure or the baseline level of chromosomal aberrations....

  7. Common polymorphisms in the microsomal epoxide hydrolase and N-acetyltransferase 2 genes in association with inflammatory bowel disease in the Danish population

    DEFF Research Database (Denmark)

    Ernst, Anja; Andersen, Vibeke; Ostergaard, Mette

    2011-01-01

    Chronic inflammatory bowel disease (IBD) is characterized by recurrent inflammation of the intestinal mucosa. Reactive molecules play a central role in altering the intestinal permeability, which may induce or sustain an immune response. Changes in detoxification of substances that causes...

  8. Circadian Dynamics of the Cone-Rod Homeobox (CRX) Transcription Factor in the Rat Pineal Gland and Its Role in Regulation of Arylalkylamine N-Acetyltransferase (AANAT)

    DEFF Research Database (Denmark)

    Rohde, Kristian; Rovsing, Louise; Ho, Anthony K

    2014-01-01

    that the rhythmic nature of pineal CRX protein may directly modulate the daily profile of Aanat expression by inducing nighttime expression of this enzyme, thus facilitating nocturnal melatonin synthesis in addition to its role in ensuring a correct tissue distribution of Aanat expression....

  9. Homeobox genes and melatonin synthesis

    DEFF Research Database (Denmark)

    Rohde, Kristian; Møller, Morten; Rath, Martin Fredensborg

    2014-01-01

    Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based indu......Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a c......AMP response element-based circadian melatonin production....

  10. The enhanced bladder cancer susceptibility of NAT2 slow acetylators towards aromatic amines: a review considering ethnic differences.

    Science.gov (United States)

    Golka, Klaus; Prior, Verena; Blaszkewicz, Meinolf; Bolt, Hermann M

    2002-03-10

    Human bladder cancer may be caused by exposure to aromatic amines. The polymorphic enzyme N-acetyltransferase 2 (NAT2) is involved in the metabolism of these compounds. Two classical studies on chemical workers in Europe, exposed in the past to aromatic amines like benzidine, unambiguously showed that the slow acetylator status is a genetic risk factor for arylamine-induced bladder cancer. In the former benzidine industry in Huddington, Great Britain, 22 of 23 exposed cases with bladder cancer, but only 57% of 95 local controls without bladder cancer were of the slow acetylator phenotype. In Leverkusen, Germany, 82% of 92 benzidine-exposed chemical workers with bladder cancer were of the slow acetylator phenotype, whereas only 48% of 331 chemical workers who had worked at that plant were of the slow acetylator phenotype. This is in line with several smaller studies, which also show an over-representation of the slow acetylator status in formerly arylamine-exposed subjects with bladder cancer. Some of these studies included also subjects that were exposed to aromatic amines by having applied dyes, paints and varnishes. These European findings are in contrast to a large study on Chinese workers occupationally exposed to aromatic amines. In this study, only five of 38 bladder cancer cases occupationally exposed to arylamines were of the slow acetylator genotype. This is much lower than the ratio of slow acetylators to the general population in China. This points to different mechanisms of susceptibility for bladder cancer upon exposure to aromatic amines between European (Caucasian) and Chinese populations.

  11. GENETISCHE ASPECTEN BIJ HET METABOLISME VAN GENEESMIDDELEN : DE INTERINDIVIDUELE VERSCHILLEN VERDER ONTRAFELD

    NARCIS (Netherlands)

    Touw, D.J.

    1998-01-01

    For many enzymes involved in drug metabolism different phenotypes have been discovered with a wide range of enzymatic activity. In this way, oxidation (by cytochrome P450), N-acetylation (by N-acetyltransferase), glucuronidation (by uridine glucuronosyl transferase), sulfation (by sulfotransferase)

  12. Theoretical studies of the tautomerism in 3-(2-R-Phenylhydrazono)-naphthalene- 1,2,4-triones: synthesis of copper(II) complexes and studies of antibacterial and antitumor activities

    Energy Technology Data Exchange (ETDEWEB)

    Francisco, Acacio I.; Vargas, Maria D.; Fragoso, Thais P.; Carneiro, J. Walkimar de M.; Silva, Fernando de C. da; Ferreira, Vitor F., E-mail: mdvargas@vm.uff.b [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Quimica; Casellato, Annelise [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica; Barbosa, Jussara P. [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil); Pessoa, Claudia; Costa-Lotufo, Leticia V.; Marinho Filho, Jose D.B.; Moraes, Manoel O. de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Fisiologia e Farmacologia; Mangrich, Antonio S. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica

    2010-07-01

    DFT calculations using the B3LYP and PBE1PBE functionals with the standard 6-31G(d) and 6-311+G(2d,p) basis sets were carried out for the 3-(2-phenylhydrazone)-naphthalene-1,2,4-trione system in solution (dmso) and in the gas phase, and showed the keto-hydrazone forms (rotamers Ia and Ib) to be more stable than the enol-azo forms (rotamers IIa and IIb, by about 14 kcal mol-1) and III (by approximately 6 kcal mol-1), independently of the nature of the substituent in the phenylene ring. These results were confirmed by spectroscopic data on the derivatives HL1-HL13, obtained from 2-hydroxy-1,4-naphthoquinone and arylamines (R = 4-OMe, 4-N{sub 2}-C{sub 6}H{sub 5}, 4-Cl, 4-I, 3-I, 2-I, 4-COOH, 3-COOH, 4-CN, 3-CN, 4-NO{sub 2}, 3-NO{sub 2}, 2-NO{sub 2}). The in vitro antitumor (against SF-295, HCT-8, MDAMB-435 and HL-60 cancer cell lines) and antibacterial activities (Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa) of compounds HL1-HL13 and of their respective copper(II) complexes, [Cu(L1-13){sub 2}], were tested. In general, these compounds exhibited low antibacterial activity, except for HL5 (R 3-I), more active than the control; however, the corresponding complex was inactive. In contrast, increased cytotoxicity was observed upon complexation. Complex [Cu(L13){sub 2}] (R = 3-NO{sub 2}) presented moderate cytotoxicity against human leukemia (HL-60). (author)

  13. Circadian Expression of the Arylalkylamine N-acetyltransferase Gene in the Rat Pineal Gland%大鼠松果体N-乙酰转移酶基因的昼夜节律性表达

    Institute of Scientific and Technical Information of China (English)

    王国卿; 杜玉珍; 童建

    2005-01-01

    探讨12 h光照、12 h黑暗交替(LD)光制下松果体N-乙酰转移酶(NAT)基因的昼夜节律性表达.SD大鼠在LD光制下饲养4周后,在一昼夜内每隔4 h采集一组松果体组织,提取总RNA,进行竞争性定量RT-PCR,测定不同昼夜时点(ZT)样品中NAT基因mRNA的相对表达量.用余弦函数获取节律参数,并经振幅检验分析是否存在昼夜节律.结果表明松果体NAT基因mRNA表达呈现昼夜节律性振荡(P<0.05),峰值(mRNA水平为1.07±0.23)和谷值(mRNA水平为0.61±0.15)分别位于ZT16和ZT4,峰值相位-241.80±14.94,振幅0.23±0.13,中值0.84±0.11.证实LD光制下松果体NAT基因存在明显的昼低夜高节律性表达.

  14. Synt hesis and Antitumor Activities of N- (2′-arylaminepyrimidin4′-yl) -N,2,3-trimethyl-2H-indazol-6-amine Derivatives%新型N-(2′-芳胺嘧啶4′-基)-N,2,3-三甲基-2H-吲唑-6-胺衍生物的合成及其抗肿瘤活性

    Institute of Scientific and Technical Information of China (English)

    龙丽; 刘冰妮; 刘默; 储德清; 祁浩飞; 王景阳; 刘登科

    2011-01-01

    以3-甲基-6-硝基-1H-吲唑为原料,经N-甲基化、催化还原、亲核取代及烷基化反应制得关键中间体N-(2′-氯嘧啶-4′-基)-N,2,3-三甲基-2H吲唑-6-胺(5);5与芳胺经亲核取代反应合成了一系列新型的N-(2′-芳胺嘧啶4′-基)-N,2,3-三甲基-2H-吲唑-6-胺衍生物,其结构经1 H NMR和MS确证.初步生物活性测试结果表明,部分化合物具有明显的抗肿瘤活性.%A key medicine intermedia, N-(2'-chloropyrimidin-4'-yl)-W,2,3-trimethyl-2H-indazol-6-amine(5), was obtained by N-methylation, catalytic reduction, nucleophilic substitution and alkylat-ed reaction from 3-methyl-6-nitro-1H-indazole. Eleven novel N-(2'-arylaminepyrimidin-4'-yl)-N,2, 3-trimethyl-2H-indazol-6-amine derivatives were synthesized by nucleophilic substitution of 5 with arylamine. The structures were characterized by 1 H NMR and EI-MS. The preliminary bioassay test indicates that some of them exhibited obvious antitumor activities.

  15. Biotransformation of Trichoderma spp. and their tolerance to aromatic amines, a major class of pollutants.

    Science.gov (United States)

    Cocaign, Angélique; Bui, Linh-Chi; Silar, Philippe; Chan Ho Tong, Laetitia; Busi, Florent; Lamouri, Aazdine; Mougin, Christian; Rodrigues-Lima, Fernando; Dupret, Jean-Marie; Dairou, Julien

    2013-08-01

    Trichoderma spp. are cosmopolitan soil fungi that are highly resistant to many toxic compounds. Here, we show that Trichoderma virens and T. reesei are tolerant to aromatic amines (AA), a major class of pollutants including the highly toxic pesticide residue 3,4-dichloroaniline (3,4-DCA). In a previous study, we provided proof-of-concept remediation experiments in which another soil fungus, Podospora anserina, detoxifies 3,4-DCA through its arylamine N-acetyltransferase (NAT), a xenobiotic-metabolizing enzyme that enables acetyl coenzyme A-dependent detoxification of AA. To assess whether the N-acetylation pathway enables AA tolerance in Trichoderma spp., we cloned and characterized NATs from T. virens and T. reesei. We characterized recombinant enzymes by determining their catalytic efficiencies toward several toxic AA. Through a complementary approach, we also demonstrate that both Trichoderma species efficiently metabolize 3,4-DCA. Finally, we provide evidence that NAT-independent transformation is solely (in T. virens) or mainly (in T. reesei) responsible for the observed removal of 3,4-DCA. We conclude that T. virens and, to a lesser extent, T. reesei likely utilize another, unidentified, metabolic pathway for the detoxification of AA aside from acetylation. This is the first molecular and functional characterization of AA biotransformation in Trichoderma spp. Given the potential of Trichoderma for cleanup of contaminated soils, these results reveal new possibilities in the fungal remediation of AA-contaminated soil.

  16. Tryptophan hydroxylase is modulated by L-type calcium channels in the rat pineal gland.

    Science.gov (United States)

    Barbosa, Roseli; Scialfa, Julieta Helena; Terra, Ilza Mingarini; Cipolla-Neto, José; Simonneaux, Valérie; Afeche, Solange Castro

    2008-02-27

    Calcium is an important second messenger in the rat pineal gland, as well as cAMP. They both contribute to melatonin synthesis mediated by the three main enzymes of the melatonin synthesis pathway: tryptophan hydroxylase, arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase. The cytosolic calcium is elevated in pinealocytes following alpha(1)-adrenergic stimulation, through IP(3)-and membrane calcium channels activation. Nifedipine, an L-type calcium channel blocker, reduces melatonin synthesis in rat pineal glands in vitro. With the purpose of investigating the mechanisms involved in melatonin synthesis regulation by the L-type calcium channel, we studied the effects of nifedipine on noradrenergic stimulated cultured rat pineal glands. Tryptophan hydroxylase, arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase activities were quantified by radiometric assays and 5-hydroxytryptophan, serotonin, N-acetylserotonin and melatonin contents were quantified by HPLC with electrochemical detection. The data showed that calcium influx blockaded by nifedipine caused a decrease in tryptophan hydroxylase activity, but did not change either arylalkylamine N-acetyltransferase or hydroxyindole-O-methyltransferase activities. Moreover, there was a reduction of 5-hydroxytryptophan, serotonin, N-acetylserotonin and melatonin intracellular content, as well as a reduction of serotonin and melatonin secretion. Thus, it seems that the calcium influx through L-type high voltage-activated calcium channels is essential for the full activation of tryptophan hydroxylase leading to melatonin synthesis in the pineal gland.

  17. Daytime Unresponsiveness of the Human and Syrian Hamster Pineal to Adrenergic Stimulation

    Science.gov (United States)

    1989-01-01

    depresses nighttime melatonin content without changing N-acetyltransferase activity in the rat pineal gland . Neuroendocrinology 47, 55-60. Vaughan, G.M...exposure) raises pineal melatonin content; injection outside this sensitive period does not. (CajP-" This dramatic change in response of the pineal gland ...in rats , though the change is small in rats with functional pineal nerve endinvs. Ether anesthesia (G.M. Vaughan and J.P. Allen, unpublished results

  18. Crystal Structure of the Zorbamycin-Binding Protein ZbmA, the Primary Self-Resistance Element in Streptomyces flavoviridis ATCC21892

    Energy Technology Data Exchange (ETDEWEB)

    Rudolf, Jeffrey D. [Scripps Research Inst., Jupiter, FL (United States); Bigelow, Lance [Argonne National Lab. (ANL), Argonne, IL (United States); Chang, Changsoo [Argonne National Lab. (ANL), Argonne, IL (United States); Cuff, Marianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Lohman, Jeremy R. [Scripps Research Inst., Jupiter, FL (United States); Chang, Chin-Yuan [Scripps Research Inst., Jupiter, FL (United States); Ma, Ming [Scripps Research Inst., Jupiter, FL (United States); Yang, Dong [Scripps Research Inst., Jupiter, FL (United States); Clancy, Shonda [Argonne National Lab. (ANL), Argonne, IL (United States); Babnigg, Gyorgy [Argonne National Lab. (ANL), Argonne, IL (United States); Joachimiak, Andrzej [Argonne National Lab. (ANL), Argonne, IL (United States); Phillips, George N. [Rice Univ., Houston, TX (United States); Shen, Ben [Scripps Research Inst., Jupiter, FL (United States)

    2015-11-17

    The bleomycins (BLMs), tallysomycins (TLMs), phleomycin, and zorbamycin (ZBM) are members of the BLM family of glycopeptide-derived antitumor antibiotics. The BLM-producing Streptomyces verticillus ATCC15003 and the TLM-producing Streptoalloteichus hindustanus E465-94 ATCC31158 both possess at least two self-resistance elements, an N-acetyltransferase and a binding protein. The N-acetyltransferase provides resistance by disrupting the metal-binding domain of the antibiotic that is required for activity, while the binding protein confers resistance by sequestering the metal-bound antibiotic and preventing drug activation via molecular oxygen. We recently established that the ZBM producer, Streptomyces flavoviridis ATCC21892, lacks the N-acetyltransferase resistance gene and that the ZBM-binding protein, ZbmA, is sufficient to confer resistance in the producing strain. To investigate the resistance mechanism attributed to ZbmA, we determined the crystal structures of apo and Cu(II)-ZBM-bound ZbmA at high resolutions of 1.90 and 1.65 angstrom, respectively. A comparison and contrast with other structurally characterized members of the BLM-binding protein family revealed key differences in the protein ligand binding environment that fine-tunes the ability of ZbmA to sequester metal-bound ZBM and supports drug sequestration as the primary resistance mechanism in the producing organisms of the BLM family of antitumor antibiotics.

  19. HGSNAT has a TATA-less promoter with multiple starts of transcription.

    Science.gov (United States)

    Richtrova, Eva; Mrazova, Lenka S; Musalkova, Dita; Luksan, Ondrej; Stolnaya, Larisa; Minks, Jakub; Lukas, Jan; Dvorakova, Lenka; Jirsa, Milan; Hrebicek, Martin

    2016-10-30

    Acetyl-CoA:α-glucosaminide N-acetyltransferase (N-acetyltransferase) is a lysosomal membrane enzyme that catalyzes a key step in the lysosomal degradation of heparan sulfate. Its deficiency causes Sanfilippo syndrome type IIIC (Mucopolysaccharidosis type IIIC, MPS IIIC). Here we characterize the promoter region of HGSNAT, the gene encoding N-acetyltransferase, which is located in the pericentromeric region of chromosome 8. We show that HGSNAT transcription is driven by a TATA-less promoter whose key elements are contained within the 1054bp region upstream of exon 1. About 400 bases of the region's 3'-prime end overlap with an unmethylated CpG island. Reduced reporter activities from promoter serial deletion constructs suggested strong regulatory elements at positions -101 to -20bp and -1073 to -716bp of the downstream initiation codon (DS-ATG). Targeted mutagenesis of the first Specificity protein 1-A (Sp1-A) of the six in silico-predicted Sp1 sites in the region flanking the major transcription start sites (TSSs, +50/-101) led to a 55% decrease of reporter activity, while inactivation of each of Sp1-B and Sp1-C resulted in its almost two-fold increase. The binding of Sp1 to the region was confirmed by chromatin immunoprecipitation (ChIP). Overall, this confirms that Sp1 is important for regulation of the HGSNAT promoter. Promoter fragments in antisense orientation (constructs pGL4 -20/-1305 and pGL4 +50/-1305) led to reporter activities of about 50% of the pGL4 -1305/-20 activity, implying divergent initiation of transcription at the promoter. We identified two main TSSs at positions +1 and -15 from DS-ATG using Rapid amplification of cDNA ends (5'RACE). Transcripts initiating at the TSSs thus contain only DS-ATG. Five patients from our MPS IIIC cohort (n=23) carried the rs4523300 promoter variant and one the rs149596192 promoter variant. Both variants lowered the expression of the reporter down to 68% and 59%, respectively. However, white blood cell (WBC) N-acetyltransferase

  20. Frequency of NAT2 and GSTP1 polymorphisms in the Kazakh population

    Directory of Open Access Journals (Sweden)

    Aisha Iskakova

    2014-01-01

    Full Text Available Introduction: Phase II xenobiotic biotransformation enzymes perform detoxification of hydrophilic and often toxic Phase I products by glutathionetransferase (GST, UDP-glucuronosyltransferase (UDF, N-acetyltransferase (NAT families and other enzymes. GST protein family metabolizes a large number of electrophilic xenobiotics, including drugs, by conjugating them with glutathione. Arylamine-N-acetyltransferase (NAT catalyzes the acetylation of the aromatic and heterocyclic amines. Materials and methods: The current study has assessed the frequencies of NAT2 and GSTP1 genes polymorphisms in 326 healthy individuals from different regions of Kazakhstan by using Real-Time PCR and direct sequencing methods. Results: Allele frequencies were derived for NAT2*5 (0.54 and GSTP1 (0.27. GSTP1 alleles were in Hardy – Weinberg equilibrium (p > 0.05, while NAT2*5 (p = 0.00 were not.  The population differences between North, Northeast and South Kazakhstan regions were determined. Statistically significant differences in the frequency of genotypes were not found. Conclusion: Allelic polymorphisms of NAT2*5 and GSTP1 genes vary widely in different populations. Kazakh population was significantly different from Asian, Caucasoid, African-American and Hispanic ones by NAT2*5 and GSTP1 genes. Allelic variants of the NAT2*5 were detected with a low frequency in Asian populations. Allelic frequency in other world populations varies from 30 to 50%. The differences between Kazakh (0.54 and the world population were statistically significant (p < 0.05. The frequency of GSTP1 (rs1695 in the African American population is 42%. The frequency of GSTP1 in Asian populations varies from 11% to 23%, in Caucasoid populations it is about 30%. The differences between Kazakh population (0.27 and other populations selected from the literature were statistically significant (p < 0.05. The study of mutations in GSTP1 and NAT2 genes is necessary to assess the risk of the development of

  1. Physical activity

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001941.htm Physical activity To use the sharing features on this page, please enable JavaScript. Physical activity -- which includes an active lifestyle and routine exercise -- ...

  2. Activated Charcoal

    Science.gov (United States)

    Activated Carbon, Animal Charcoal, Carbo Vegetabilis, Carbon, Carbón Activado, Charbon Actif, Charbon Activé, Charbon Animal, Charbon Médicinal, Charbon Végétal, Charbon Végétal Activé, Charcoal, Gas Black, Lamp Black, Medicinal Charcoal, Noir de Gaz, ...

  3. An acetyltransferase conferring tolerance to toxic aromatic amine chemicals: molecular and functional studies.

    Science.gov (United States)

    Martins, Marta; Rodrigues-Lima, Fernando; Dairou, Julien; Lamouri, Aazdine; Malagnac, Fabienne; Silar, Philippe; Dupret, Jean-Marie

    2009-07-10

    Aromatic amines (AA) are a major class of environmental pollutants that have been shown to have genotoxic and cytotoxic potentials toward most living organisms. Fungi are able to tolerate a diverse range of chemical compounds including certain AA and have long been used as models to understand general biological processes. Deciphering the mechanisms underlying this tolerance may improve our understanding of the adaptation of organisms to stressful environments and pave the way for novel pharmaceutical and/or biotechnological applications. We have identified and characterized two arylamine N-acetyltransferase (NAT) enzymes (PaNAT1 and PaNAT2) from the model fungus Podospora anserina that acetylate a wide range of AA. Targeted gene disruption experiments revealed that PaNAT2 was required for the growth and survival of the fungus in the presence of toxic AA. Functional studies using the knock-out strains and chemically acetylated AA indicated that tolerance of P. anserina to toxic AA was due to the N-acetylation of these chemicals by PaNAT2. Moreover, we provide proof-of-concept remediation experiments where P. anserina, through its PaNAT2 enzyme, is able to detoxify the highly toxic pesticide residue 3,4-dichloroaniline in experimentally contaminated soil samples. Overall, our data show that a single xenobiotic-metabolizing enzyme can mediate tolerance to a major class of pollutants in a eukaryotic species. These findings expand the understanding of the role of xenobiotic-metabolizing enzyme and in particular of NATs in the adaptation of organisms to their chemical environment and provide a basis for new systems for the bioremediation of contaminated soils.

  4. Physical Activity

    DEFF Research Database (Denmark)

    Andersen, Lars Bo; Anderssen, Sigmund Alfred; Wisløff, Ulrik

    2014-01-01

    Andersen LB, Anderssen SA, Wisløff U, Hellénius M-L, Fogelholm M, Ekelund U. (Expert Group) Nordic Nutrition Recommendations 2012. Integrating nutrition and physical activity. Chapter: Physical Activity p. 195-217.Nordic Counsil of Ministers.......Andersen LB, Anderssen SA, Wisløff U, Hellénius M-L, Fogelholm M, Ekelund U. (Expert Group) Nordic Nutrition Recommendations 2012. Integrating nutrition and physical activity. Chapter: Physical Activity p. 195-217.Nordic Counsil of Ministers....

  5. Activity Theory.

    Science.gov (United States)

    Koschmann, Timothy; Roschelle, Jeremy; Nardi, Bonnie A.

    1998-01-01

    Includes three articles that discuss activity theory, based on "Context and Consciousness." Topics include human-computer interaction; computer interfaces; hierarchical structuring; mediation; contradictions and development; failure analysis; and designing educational technology. (LRW)

  6. Identifying Activity

    CERN Document Server

    Lewis, Adrian S

    2009-01-01

    Identification of active constraints in constrained optimization is of interest from both practical and theoretical viewpoints, as it holds the promise of reducing an inequality-constrained problem to an equality-constrained problem, in a neighborhood of a solution. We study this issue in the more general setting of composite nonsmooth minimization, in which the objective is a composition of a smooth vector function c with a lower semicontinuous function h, typically nonsmooth but structured. In this setting, the graph of the generalized gradient of h can often be decomposed into a union (nondisjoint) of simpler subsets. "Identification" amounts to deciding which subsets of the graph are "active" in the criticality conditions at a given solution. We give conditions under which any convergent sequence of approximate critical points finitely identifies the activity. Prominent among these properties is a condition akin to the Mangasarian-Fromovitz constraint qualification, which ensures boundedness of the set of...

  7. Activating schoolyards

    DEFF Research Database (Denmark)

    Andersen, Henriette Bondo; Pawlowski, Charlotte Skau; Scheller, Hanne Bebendorf;

    2015-01-01

    BACKGROUND: The aim of the Activating Schoolyards Study is to develop, implement, document and assess a comprehensive schoolyard intervention to promote physical activity (PA) during school recess for primary school children (grade 4-8). The intervention is designed to implement organizational...... to objectively determine where and how active the students are in the schoolyard, before and after the intervention. This provides a type of data that, to our knowledge, has not been used before in schoolyard interventions. Exploring the change in behavior in relation to specific intervention elements...... as well as quantitative methods can be seen as a strength, as the different types of data complement each other and results of one part of the study informed the following parts. A unique aspect of our study is the use of accelerometers in combination with GPS and GIS in the effect evaluation...

  8. Active house

    DEFF Research Database (Denmark)

    Eriksen, Kurt Emil; Olesen, Gitte Gylling Hammershøj

    2010-01-01

    Formålet med dette abstrakt er at illustrere, at huse kan være konstrueret til at basere sig udelukkende på vedvarende energikilder og samtidig være CO2-neutrale og producere mere energi end de forbruger. Active House Visionen undersøger disse muligheder i otte demonstration huse i fem forskellige...

  9. Get Active

    Science.gov (United States)

    ... Have fun with your family. If you have children, you can be a role model for making healthy choices. Encourage your whole family to get active outside . Go for a hike or organize a family soccer game. If someone you know has trouble making ...

  10. Drug elimination function of rat small intestine: metabolism and intraluminal excretion.

    Science.gov (United States)

    Yasuhara, M; Kurosaki, Y; Kimura, T; Sezaki, H

    1984-10-15

    The metabolic and excretory function of the small intestine was investigated after oral and intravenous administration of drugs having an aromatic amino group to rats. After administration of drugs into the intestinal loop at the initial concentration of 0.1 mM, significant excretion of their N-acetylated forms into the lumen was observed. The amount of N-acetyl forms excreted in the lumen were 39.3 +/- 3.5, 63.5 +/- 20.9 and 18.0 +/- 13.8% of disappeared drugs from the lumen for p-aminobenzoic acid (PABA), p-aminosalicylic acid and sulfanilic acid, respectively. The excretion of p-acetamidobenzoic acid (Ac-PABA) after the absorption of PABA was reduced by the coadministration with salicylic acid, benzoic acid and 2,4-dinitrophenol. Salicylic acid noncompetitively inhibited the acetylation of PABA by the intestinal N-acetyltransferase. A good correlation was found between the intestinal N-acetyltransferase activities for drugs and the intraluminal excretion of N-acetyl derivatives after intestinal absorption of drugs. These results indicate that a drug having a higher susceptibility to intestinal N-acetyltransferase would undergo a greater excretion into the lumen in its N-acetyl form after intestinal absorption. After intravenous administration of PABA at a dose of 100 mumole/kg, 4.02 +/- 0.51% of dose was excreted in the lumen as Ac-PABA in 30 min. On the other hand, a significantly smaller fraction (2.72 +/- 0.68% of dose) was excreted in the lumen after intravenous injection of 100 mumole/kg of Ac-PABA. The larger excretion of Ac-PABA after administration of PABA indicates the contribution of intestinal metabolism on the transfer of PABA not only after oral, but also after intravenous administration.

  11. Active particles

    CERN Document Server

    Degond, Pierre; Tadmor, Eitan

    2017-01-01

    This volume collects ten surveys on the modeling, simulation, and applications of active particles using methods ranging from mathematical kinetic theory to nonequilibrium statistical mechanics. The contributing authors are leading experts working in this challenging field, and each of their chapters provides a review of the most recent results in their areas and looks ahead to future research directions. The approaches to studying active matter are presented here from many different perspectives, such as individual-based models, evolutionary games, Brownian motion, and continuum theories, as well as various combinations of these. Applications covered include biological network formation and network theory; opinion formation and social systems; control theory of sparse systems; theory and applications of mean field games; population learning; dynamics of flocking systems; vehicular traffic flow; and stochastic particles and mean field approximation. Mathematicians and other members of the scientific commu...

  12. Laboratory Activities

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Christopher F.; Serne, R. Jeffrey

    2008-01-17

    This chapter summarizes the laboratory activities performed by PNNL’s Vadose Zone Characterization Project in support of the Tank Farm Vadose Zone Program, led by CH2M HILL Hanford Group, Inc. The results of these studies are contained in numerous reports (Lindenmeier et al. 2002; Serne et al. 2002a, 2002b, 2002c, 2002d, 2002e; Lindenmeier et al. 2003; Serne et al. 2004a, 2004b; Brown et al. 2005, 2006a, 2007; Serne et al. 2007) and have generated much of the data reported in Chapter 22 (Geochemistry-Contaminant Movement), Appendix G (Geochemistry-Contaminant Movement), and Cantrell et al. (2007, SST WMA Geochemistry Data Package – in preparation). Sediment samples and characterization results from PNNL’s Vadose Zone Characterization Project are also shared with other science and technology (S&T) research projects, such as those summarized in Chapter 12 (Associated Science Activities).

  13. Antimicrobial Activity.

    Science.gov (United States)

    2016-01-01

    Natural products of higher plants may possess a new source of antimicrobial agents with possibly novel mechanisms of action. They are effective in the treatment of infectious diseases while simultaneously mitigating many of the side effects that are often associated with conventional antimicrobials. A method using scanning electron microscope (SEM) to study the morphology of the bacterial and fungal microbes and thus determining antimicrobial activity is presented in the chapter.

  14. Fumarase activity

    DEFF Research Database (Denmark)

    Nielsen, Per Mose; Eldirdiri, Abubakr; Bertelsen, Lotte Bonde

    2017-01-01

    ]fumarate conversion to [1,4-(13)C2]malate by fumarase has been proposed as a measure of necrosis in rat tumor models and in chemically induced AKI rats. Here we show that the degradation of cell membranes in connection with necrosis leads to elevated fumarase activity in plasma and urine and secondly...... that hyperpolarized [1,4-(13)C2]malate production 24 h after reperfusion correlates with renal necrosis in a 40-min unilateral ischemic rat model. Fumarase activity screening on bio-fluids can detect injury severity, in bilateral as well as unilateral AKI models, differentiating moderate and severe AKI as well...... as short- and long-term AKI. Furthermore after verification of renal injury by bio-fluid analysis the precise injury location can be monitored by in vivo measurements of the fumarase activity non-invasively by hyperpolarized [1,4-(13)C]fumarate MR imaging. The combined in vitro and in vivo biomarker of AKI...

  15. Glucokinase activators.

    Science.gov (United States)

    Filipski, Kevin J; Futatsugi, Kentaro; Pfefferkorn, Jeffrey A; Stevens, Benjamin D

    2012-07-01

    In this review we highlight recently disclosed progress in the field of small-molecule activators of the human glucokinase enzyme. Several of the reported chemotypes possess structural features that diverge from known leads; some of these modifications appear to be specifically designed to modulate tissue selectivity or discrete parameters of enzyme function (e.g., S0.5 v Vmax). This review will inform the reader of the extent of continued effort being directed toward discovery of a first-in-class drug for Type II diabetes mellitus that functions through this target. Patents were selected from those published in December 2009 up to November 2011; foreign filings were translated where possible to understand the claims and biological techniques utilized to characterize the reported glucokinase activators. Overall, there appears to be a recent trend leading to reduced patent filings for small-molecule glucokinase activators. There are many possible explanations for this trend; however, it is likely that the field has reached maturity and that the downturn of new disclosures represents the transition of many of these programs to the clinic.

  16. 大鼠松果体N-乙酰基转移酶基因的内源性昼夜表达规律%Endogenous Circadian Expression of the Arylalkylamine N-acetyltransferase Gene in the Pineal Gland of Rat

    Institute of Scientific and Technical Information of China (English)

    王国卿; 傅春玲; 李建祥; 杜玉珍; 童建

    2007-01-01

    目的 探讨大鼠松果体N-乙酰基转移酶(NAT)基因的内源性昼夜节律表达.方法 SD大鼠在持续黑暗(DD)光制下饲养8周后,在一昼夜内每隔4h采集一组松果体组织,提取总RNA,进行竞争性定量RT-PCR,测定不同昼夜时点(CT)样品中NAT基因mRNA的相对表达量,用余弦函数软件获取节律参数,并经振幅F检验分析是否存在昼夜节律.结果 松果体NAT基因mRNA的表达呈现明显的内源性节律振荡(P<0.05),峰值(mRNA水平为1.42±0.11)和谷值(mRNA水平为0.56±0.18)分别位于CT17和CT5,峰值相位-260.85±9.45,振幅0.44±0.09,中值0.99±0.12.结论 大鼠松果体NAT基因存在明显的内源性昼夜节律表达,其转录水平在主观黑夜高于主观白天.

  17. Active instruments

    DEFF Research Database (Denmark)

    Lim, Miguel Antonio; Ørberg, Jakob Williams

    2017-01-01

    themselves. We draw on two multi-year field studies of India and Denmark to investigate how national reforms and developments within the ranking industry interact in often surprising ways. Rankings do not always do what policy makers expect. We (1) highlight the activity of rankers in these two countries, (2......) show the dynamic nature of policy processes, and (3) consider the search for policy reference points among the different actors. We present rankers in motion, policies in motion, and finally the complex nature of the ranking device that needs to be both a relevant and malleable policy instrument...

  18. Active packaging with antifungal activities.

    Science.gov (United States)

    Nguyen Van Long, N; Joly, Catherine; Dantigny, Philippe

    2016-03-01

    There have been many reviews concerned with antimicrobial food packaging, and with the use of antifungal compounds, but none provided an exhaustive picture of the applications of active packaging to control fungal spoilage. Very recently, many studies have been done in these fields, therefore it is timely to review this topic. This article examines the effects of essential oils, preservatives, natural products, chemical fungicides, nanoparticles coated to different films, and chitosan in vitro on the growth of moulds, but also in vivo on the mould free shelf-life of bread, cheese, and fresh fruits and vegetables. A short section is also dedicated to yeasts. All the applications are described from a microbiological point of view, and these were sorted depending on the name of the species. Methods and results obtained are discussed. Essential oils and preservatives were ranked by increased efficacy on mould growth. For all the tested molecules, Penicillium species were shown more sensitive than Aspergillus species. However, comparison between the results was difficult because it appeared that the efficiency of active packaging depended greatly on the environmental factors of food such as water activity, pH, temperature, NaCl concentration, the nature, the size, and the mode of application of the films, in addition to the fact that the amount of released antifungal compounds was not constant with time.

  19. BAM! Physical Activity

    Science.gov (United States)

    ... Smarts Links Fuel Up for Fun Power Packing Physical Activity Xpert Opinion Activity Calendar Activity Cards Ballet Baseball ... Disaster - Are You at Risk? Disaster - Helping Hands Physical Activity - Questions Physical Activity - Active or Not, Here it ...

  20. Lung cancer in Asian women - the environment and genes

    Energy Technology Data Exchange (ETDEWEB)

    Lam, W.K. [University of Hong Kong, Pokfulam (China). Queen Mary Hospital

    2005-09-15

    The mortality rate of lung cancer in Asian women has increased significantly in the past few decades. Environmental factors include tobacco smoke (active and environmental), other indoor pollutions (cooking oil vapours, coal burning, fungus spores), diet, and infections. Active tobacco smoking is not the major factor. Cooking oil vapours associated with high temperature wok cooking and indoor coal burning for heating and cooking in unvented homes, particularly in rural areas, are risk factors for Chinese women. Chronic benign respiratory diseases due to the fungus Microsporum canis probably accounts for the high incidence of lung cancer in northern Thai women at Sarapee. Diets rich in fruits, leafy green vegetables, and vitamin A are protective, while cured meat (Chinese sausage, pressed duck and cured pork), deep-fried cooking, and chili increased the risk. Tuberculosis is associated with lung cancer. Also, a Taiwanese study showed that the odds ratio of papillomavirus (HPV) 16/18 infection in non-smoking female lung cancer patients was 10.1, strongly suggesting a causative role. Genetic factors have also been studied in Chinese women, including human leucocyte antigens, K-ras oncogene activation, p53 mutation, polymorphisms of phase I activating enzymes (cytochrome P450, N-acetyltransferase slow acetylator status), and phase II detoxifying enzymes (glutathione-S-transferases, N-acetyltransferase rapid acetylator status).

  1. AcEST: DK950447 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 2_DANRE N-acetyltransferase ESCO2 OS=Danio rerio GN=esco2 PE=2 SV=1 Length...ss-Prot sp_hit_id Q8CIB9 Definition sp|Q8CIB9|ESCO2_MOUSE N-acetyltransferase ESCO2 OS=Mus musculus Align le...g significant alignments: (bits) Value sp|Q8CIB9|ESCO2_MOUSE N-acetyltransferase ESCO2 OS=Mus musculus ... 100 1e-20 sp|Q56NI9|ESCO...2_HUMAN N-acetyltransferase ESCO2 OS=Homo sapiens ... 92 2e-18 sp|Q5FWF5|ESCO...1_HUMAN N-acetyltransferase ESCO1 OS=Homo sapiens ... 92 2e-18 sp|Q5SPR8|ESCO2_DANRE N-acetyltransferase ESCO

  2. Intangible activities

    DEFF Research Database (Denmark)

    Hermansen, Jonathan

    2016-01-01

    ‘Informal helping’ is often associated with other types of prosocial behaviour such as formal voluntary work. Therefore, one could jump to the conclusion that it would be the same factors driving both types of activities. This article demonstrates that this is not the case. The study relies...... on a population survey on informal helping and volunteering in Denmark. The two contributions of this article are as follows: (1) it demonstrates that the sociodemographic indicators that are closely linked to formal volunteering are not related to informal helping in the same manner and (2) it demonstrates...... that it is necessary to separate the decision to help and the amount of hours that people help, a distinction that previous empirical studies on this topic fail to include. The results show that informal helping may not simply be compared to other instances of prosocial behaviour. In particular, the socio...

  3. Active sharing

    CERN Multimedia

    2012-01-01

    The big news this week is, of course, the conclusions from the LHC performance workshop held in Chamonix from 6 to 10 February . The main recommendation, endorsed by CERN’s Machine Advisory Committee and adopted by the Management, is that the LHC will run at 4 TeV per beam this year. You can find all the details from Chamonix in the slides presented on Wednesday at the summary session, which leaves me free to talk about another important development coming up soon.   In ten days time, a new kind of gathering will be taking place in Geneva, bringing together two previously separate conferences, one driven by physics, the other by the medical community, but both looking to apply physics to the advancement of health. The merger of the International Conference for Translational Research in Radio-Oncology and CERN’s workshop on Physics for Health in Europe (ICTR-PHE) makes for a very eclectic mix. Presentations range from active shielding for interplanetary flight to the rather...

  4. DAVIC activities

    Science.gov (United States)

    Fujiwara, Hiroshi

    1995-12-01

    DAVIC (Digital Audio Visual Council) is the defacto standardization organization established in Mar. 1994, based on international consensus for digital audio visual services. After completion of MPEG2 standardization, the broadcasting industry, the communication industry, the computer industry, and consumer electronics industry have started development of concrete services and products. Especially the interactive digital audio visual services, such as Video On Demand (VOD) or Near Video On Demand (NVOD), have become hot topics all over the world. Such interactive digital audio visual services are combined technologies of multi-media coding, digital transmission and computer networking. Therefore more than 150 organizations from all industry sectors have participated in DAVIC and are contributing from their own industrial contexts. DAVIC's basic policy is to use the available technologies specified by the other standards bodies as much as possible. So DAVIC's standardization activities have close relationship with ISO IEC/JTC1/SC29, ITU-T SG 9, ATM-Forum, IETF, IMA, DVB, etc. DAVIC is trying to specify Applications, Reference Models, Security, Usage Information Control, and the interfaces and protocols among the Content Provider, the Server, the core network, the access network, and the Set Top Unit. DAVIC's first goal is to specify DAVIC1.0 based on CFP1 (Call for Proposal) and CFP2 by Dec. 1995, and the next direction is under preparation for further progress based on CFP3 and CFP4.

  5. Power Conversion Efficiency of Arylamine Organic Dyes for Dye-Sensitized Solar Cells (DSSCs) Explicit to Cobalt Electrolyte: Understanding the Structural Attributes Using a Direct QSPR Approach

    OpenAIRE

    Supratik Kar; Juganta K. Roy; Danuta Leszczynska; Jerzy Leszczynski

    2016-01-01

    Post silicon solar cell era involves light-absorbing dyes for dye-sensitized solar systems (DSSCs). Therefore, there is great interest in the design of competent organic dyes for DSSCs with high power conversion efficiency (PCE) to bypass some of the disadvantages of silicon-based solar cell technologies, such as high cost, heavy weight, limited silicon resources, and production methods that lead to high environmental pollution. The DSSC has the unique feature of a distance-dependent electron...

  6. IASS Activity

    Science.gov (United States)

    Hojaev, Alisher S.; Ibragimova, Elvira M.

    2015-08-01

    It’s well known, astronomy in Uzbekistan has ancient roots and traditions (e.g., Mirzo Ulugh Beg, Abū al-Rayhān al-Bīrūnī, Abū ‘Abdallāh al-Khwārizmī) and astronomical heritage carefully preserved. Nowadays uzbek astronomers play a key role in scientific research but also in OAD and Decadal Plan activity in the Central Asia region. International Aerospace School (IASS) is an amazing and wonderful event held annually about 30 years. IASS is unique project in the region, and at the beginning we spent the Summer and Winter Schools. At present in the summer camp we gather about 50 teenage and undergraduate students over the country and abroad (France, Malaysia, Turkey, Azerbaijan, Pakistan, Russia, etc.). They are selected on the basis of tests of astronomy and space issues. During two weeks of IASS camp the invited scientists, cosmonauts and astronauts as well as other specialists give lectures and engage in practical exercises with IASS students in astronomy, including daily observations of the Sun and night sky observations with meniscus telescope, space research and exploration, aerospace modelling, preparation and presentation of original projects. This is important that IASS gives not theoretical grounds only but also practically train the students and the hands-on training is the major aims of IASS. Lectures and practice in the field of astronomy carried out with the direct involvement and generous assistance of Uranoscope Association (Paris, France). The current 26-th IASS is planned to held in July 2015.

  7. The crystal structure of Rv1347c, a putative antibiotic resistance protein from Mycobacterium tuberculosis, reveals a GCN5-related fold and suggests an alternative function in siderophore biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Card, G L; Peterson, N A; Smith, C A; Rupp, B; Schick, B M; Baker, E N

    2005-02-15

    Mycobacterium tuberculosis, the cause of TB, is a devastating human pathogen. The emergence of multi-drug resistance in recent years has prompted a search for new drug targets and for a better understanding of mechanisms of resistance. Here we focus on the gene product of an open reading frame from M. tuberculosis, Rv1347c, which is annotated as a putative aminoglycoside N-acetyltransferase. The Rv1347c protein does not show this activity, however, and we show from its crystal structure, coupled with functional and bioinformatic data, that its most likely role is in the biosynthesis of mycobactin, the M. tuberculosis siderophore. The crystal structure of Rv1347c was determined by MAD phasing from selenomethionine-substituted protein and refined at 2.2 {angstrom} resolution (R = 0.227, R{sub free} = 0.257). The protein is monomeric, with a fold that places it in the GCN5-related N-acetyltransferase (GNAT) family of acyltransferases. Features of the structure are an acylCoA binding site that is shared with other GNAT family members, and an adjacent hydrophobic channel leading to the surface that could accommodate long-chain acyl groups. Modeling the postulated substrate, the N{sup {var_epsilon}}-hydroxylysine side chain of mycobactin, into the acceptor substrate binding groove identifies two residues at the active site, His130 and Asp168, that have putative roles in substrate binding and catalysis.

  8. Activation Energy

    Science.gov (United States)

    Gadeken, Owen

    2002-01-01

    Teaming is so common in today's project management environment that most of us assume it comes naturally. We further assume that when presented with meaningful and challenging work, project teams will naturally engage in productive activity to complete their tasks. This assumption is expressed in the simple (but false) equation: Team + Work = Teamwork. Although this equation appears simple and straightforward, it is far from true for most project organizations whose reality is a complex web of institutional norms based on individual achievement and rewards. This is illustrated by the very first successful team experience from my early Air Force career. As a young lieutenant, I was sent to Squadron Officer School, which was the first in the series of Air Force professional military education courses I was required to complete during my career. We were immediately formed into teams of twelve officers. Much of the course featured competition between these teams. As the most junior member of my team, I quickly observed the tremendous pressure to show individual leadership capability. At one point early in the course, almost everyone in our group was vying to become the team leader. This conflict was so intense that it caused us to fail miserably in our first outdoor team building exercise. We spent so much time fighting over leadership that we were unable to complete any of the events on the outdoor obstacle course. This complete lack of success was so disheartening to me that I gave our team little hope for future success. What followed was a very intense period of bickering, conflict, and even shouting matches as our dysfunctional team tried to cope with our early failures and find some way to succeed. British physician and researcher Wilfred Bion (Experiences in Groups, 1961) discovered that there are powerful psychological forces inherent in all groups that divert from accomplishing their primary tasks. To overcome these restraining forces and use the potential

  9. Biotransformation in Egyptian spiny mouse Acomys cahirinus.

    Science.gov (United States)

    Watkins, J B; LaFollette, J W; Sanders, R A

    1995-01-01

    The activities of several representative biotransformation enzymes were determined in male and female spiny mouse tissues. Cytochrome P450 monooxygenase activity toward benzo(a)pyrene was significantly greater in female spiny mouse intestine than in males. Activity toward benzphetamine in both sexes was high in the liver, with little activity in the kidney and intestine. Sulfotransferase activity was high in kidney and intestine of female spiny mice but undetectable in the same tissues in males. Hepatic glutathione S-transferase activity towards 1-chloro-2,4-dinitrobenzene in females was significantly higher than in males. UDP-Glucuronosyltransferase activity toward 1-naphthol in both sexes in the kidney was significantly higher than hepatic and intestinal activity. Intestinal N-acetyltransferase activity towards 2-aminofluorene and beta-naphthylamine was significantly greater in females than males. No consistent relation appeared to exist between biotransformation activities in spiny mouse and those in other related rodent species.

  10. Effects of Tibetan Medicine Zuotai on the Activities of CYP1A2 and NAT2 in Rats%藏药佐太对大鼠CYP1A2和NAT2活性的影响

    Institute of Scientific and Technical Information of China (English)

    范雪汝; 朱俊博; 姚星辰; 袁明; 李向阳

    2015-01-01

    目的:研究藏药佐太对大鼠细胞色素氧化酶(CYP1A2)、药物代谢酶N-乙酰基转移酶2(NAT2)活性的影响。方法:将70只SD大鼠随机均分为正常对照(生理盐水)组和佐太低、中、高剂量(1.2、3.8、12 mg/kg)单次给药组和多次给药组(每天1次,连续12 d),分别ig给药。正常对照组、佐太单次给药组于第2天,佐太多次给药组于第13天分别ig给予咖啡因(25 mg/kg),5 h后采集尿液,按10 mg/ml加入维生素C。采用高效液相色谱法测定大鼠尿液中咖啡因代谢物5-乙酰氨基-6-甲酰氨基-3-甲基尿酸(AFMU)、1-甲基黄嘌呤(1X)、1-甲基尿酸(1U)、1,7-二甲基尿酸(17U)的含量,以(AFMU+1X+1U)/17U、AFMU/(AFMU+1X+1U)比值来反映CYP1A2和NAT2活性。结果:与正常对照组比较,佐太中剂量单次给药组及多次给药组、高剂量多次给药组大鼠(AFMU+1X+1U)/17U、AFMU/(AFMU+1X+1U)比值降低,即CYP1A2和NAT2活性降低,差异有统计学意义(P<0.05)。结论:佐太对大鼠CYP1A2和NAT2活性有明显抑制作用。%OBJECTIVE:To study the effects of Tibetan medicine Zuotai on the activities of cytochrome oxidase (CYP1A2) and drug metabolism enzyme N-acetyltransferase 2(NAT2)in rats. METHODS:70 SD rats were equally randomized into a normal control (normal saline) group,the groups of single administration of low,middle and high-dose (1.2,3.8 and 12 mg/kg) Zuotai and the groups of multiple administrations thereof(once daily for 12 consecutive days). The rats were given drugs ig. caffeine(25 mg/kg)was given ig to the rats in the normal control group and the groups of single administration on the 2nd day,and to those in the groups of multiple administrations on the 13th day. 5 h later,their urine was collected and added with vitamin C based on 10 mg/ml. High performance liquid chromatography (HPLC) was adopted to determine the cafeine metabolites contents of 5

  11. Staying Active: Physical Activity and Exercise

    Science.gov (United States)

    ... Examples of muscle-strengthening activities include lifting weights, yoga, push-ups, and sit-ups. A “repetition” is one complete movement of an activity. To get health benefits, do muscle-strengthening activities until it is hard ...

  12. Physical Activity Assessment

    Science.gov (United States)

    Current evidence convincingly indicates that physical activity reduces the risk of colon and breast cancer. Physical activity may also reduce risk of prostate cancer. Scientists are also evaluating potential relationships between physical activity and other cancers.

  13. Immunizations: Active vs. Passive

    Science.gov (United States)

    ... Prevention > Immunizations > Immunizations: Active vs. Passive Safety & Prevention Listen Español Text Size Email Print Share Immunizations: Active vs. Passive Page Content Article Body Pediatricians can ...

  14. Political activity for physical activity: health advocacy for active transport.

    Science.gov (United States)

    Richards, Rosalina; Murdoch, Linda; Reeder, Anthony I; Amun, Qa-t-a

    2011-05-29

    Effective health advocacy is a priority for efforts to increase population participation in physical activity. Local councils are an important audience for this advocacy. The aim of the current study was to describe features of advocacy for active transport via submissions to city council annual plans in New Zealand, and the impact of an information sheet to encourage the health sector to be involved in this process. Written submissions to city council's annual consultation process were requested for 16 city councils over the period of three years (2007/08, 2008/09, and 2009/10). Submissions were reviewed and categories of responses were created. An advocacy information sheet encouraging health sector participation and summarising some of the evidence-base related to physical activity, active transport and health was released just prior to the 2009/10 submission time. Over the period of the study, city councils received 47,392 submissions, 17% of which were related to active transport. Most submissions came from city residents, with a small proportion (2%) from the health sector. The largest category of submissions was in support of pedestrian and cycling infrastructure, design and maintenance of facilities and additional features to support use of these transport modes. Health arguments featured prominently in justifications for active transport initiatives, including concerns about injury risk, obesity, physical inactivity, personal safety and facilities for people with disabilities. There was evidence that the information sheet was utilised by some health sector submitters (12.5%), providing tentative support for initiatives of this nature. In conclusion, the study provides novel information about the current nature of health advocacy for active transport and informs future advocacy efforts about areas for emphasis, such as health benefits of active transport, and potential alliances with other sectors such as environmental sustainability, transport and urban

  15. Criminalisation of Activism

    DEFF Research Database (Denmark)

    Uldam, Julie

    Different forms of political participation involve different challenges. This paper focuses on challenges to radical activism and particularly the criminalisation of activism.......Different forms of political participation involve different challenges. This paper focuses on challenges to radical activism and particularly the criminalisation of activism....

  16. Active commuting to school

    Science.gov (United States)

    Declines in physical activity levels have coincided with increasing rates of obesity in children. This is problematic because physical activity has been shown to attenuate weight gain in children. Active commuting to school is one way of increasing children's physical activity. However, given the hi...

  17. Physical Activity During School

    DEFF Research Database (Denmark)

    Østergaard, Lars Domino

    It is important, not only on health grounds, to exercise and to be physically active. In school, physical activities have shown to improve the students’ academic behaviour resulting in improved attention and information processing as well as enhanced coping. To stimulate and motivate students...... to be even more active during school hours further enhancing their academic behaviour, it is important to know when, why and how they are active, and their attitude towards different types of physical activities. Therefore, the aim of this study was to categorize the physical activities attended by students...... during school hours and to elucidate their attitude towards the different types of activities. The data consisted of observations of lessons followed by group interviews. Analyses of the observations revealed six categories of physical activities, varying from mandatory physical activities, activities...

  18. Cultural Activation of Consumers.

    Science.gov (United States)

    Siegel, Carole E; Reid-Rose, Lenora; Joseph, Adriana M; Hernandez, Jennifer C; Haugland, Gary

    2016-02-01

    This column discusses "cultural activation," defined as a consumer's recognition of the importance of providing cultural information to providers about cultural affiliations, challenges, views about, and attitudes toward behavioral health and general medical health care, as well as the consumer's confidence in his or her ability to provide this information. An aid to activation, "Cultural Activation Prompts," and a scale that measures a consumer's level of activation, the Cultural Activation Measurement Scale, are described. Suggestions are made about ways to introduce cultural activation as a component of usual care.

  19. Major operations and activities

    Energy Technology Data Exchange (ETDEWEB)

    Black, D.G.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the major operations and activities on the site. These operations and activities include site management, waste management, environmental restoration and corrective actions, and research and technology development.

  20. ACS Community Activities Contests

    Science.gov (United States)

    Burgener, Marisa

    2007-08-01

    The Committee on Community Activities and the Office of Community Activities announce the winners of the Illustrated Haiku Contest, Earth Day 2007 and the Poster Contest, National Chemistry Week 2006.

  1. Active Marine Station Metadata

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Active Marine Station Metadata is a daily metadata report for active marine bouy and C-MAN (Coastal Marine Automated Network) platforms from the National Data...

  2. USAID Activity Locatons

    Data.gov (United States)

    US Agency for International Development — The USAID Activities dataset is a snapshot of activities supported by USAID including their geographical locations within countries at the time of the snapshot. The...

  3. Active magnetic regenerator

    Science.gov (United States)

    Barclay, John A.; Steyert, William A.

    1982-01-01

    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  4. Physical Activity (Exercise)

    Science.gov (United States)

    ... page Subscribe to ePublications email updates. Enter email address Submit Home > ePublications > Our ePublications > Physical activity (exercise) fact sheet ePublications Physical activity (exercise) ...

  5. Guide to Physical Activity

    Science.gov (United States)

    ... minutes Stairwalking for 15 minutes Sporting Activities Playing volleyball for 45–60 minutes Playing touch football for ... strenuous activities. Competitive sports, such as tennis and volleyball, can provide an enjoyable form of exercise for ...

  6. Italian active volcanoes

    Institute of Scientific and Technical Information of China (English)

    RobertoSantacroce; RenawCristofolini; LuigiLaVolpe; GiovanniOrsi; MauroRosi

    2003-01-01

    The eruptive histories, styles of activity and general modes of operation of the main active Italian volcanoes,Etna, Vulcano, Stromboli, Vesuvio, Campi Flegrei and Ischia, are described in a short summary.

  7. Facts about Physical Activity

    Science.gov (United States)

    ... Nutrition Physical Activity Overweight & Obesity Healthy Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Facts about Physical ... Nutrition Physical Activity Overweight & Obesity Healthy Weight Breastfeeding Micronutrient Malnutrition State and Local Programs File Formats Help: ...

  8. Family Activities for Fitness

    Science.gov (United States)

    Grosse, Susan J.

    2009-01-01

    This article discusses how families can increase family togetherness and improve physical fitness. The author provides easy ways to implement family friendly activities for improving and maintaining physical health. These activities include: walking, backyard games, and fitness challenges.

  9. Activity Theory and Ontology

    Science.gov (United States)

    Peim, Nick

    2009-01-01

    This paper seeks to re-examine Yrio Engestrom's activity theory as a technology of knowledge designed to enable positive transformations of specific practices. The paper focuses on a key paper where Engestrom defines the nature and present state of activity theory. Beginning with a brief account of the relations between activity theory and…

  10. Measurement of Physical Activity.

    Science.gov (United States)

    Dishman, Rod K.; Washburn, Richard A.; Schoeller, Dale A.

    2001-01-01

    Valid assessment of physical activity must be unobtrusive, practical to administer, and specific about physical activity type, frequency, duration, and intensity. Assessment methods can be categorized according to whether they provide direct or indirect (e.g., self-report) observation of physical activity, body motion, physiological response…

  11. Ras activation by SOS

    DEFF Research Database (Denmark)

    Iversen, Lars; Tu, Hsiung-Lin; Lin, Wan-Chen;

    2014-01-01

    Activation of the small guanosine triphosphatase H-Ras by the exchange factor Son of Sevenless (SOS) is an important hub for signal transduction. Multiple layers of regulation, through protein and membrane interactions, govern activity of SOS. We characterized the specific activity of individual ...

  12. Proteolytic activities in yeast.

    Science.gov (United States)

    Saheki, T; Holzer, H

    1975-03-28

    Studies on the mechanism and time course of the activation of proteinases A (EC 3.4.23.8), B (EC 3.4.22.9) and C (EC 3.4.12.--) in crude yeast extracts at pH 5.1 and 25 degrees C showed that the increase in proteinase B activity is paralleled with the disappearance of proteinase B inhibitor. Addition of purified proteinase A to fresh crude extracts accelerates the inactivation of the proteinase B inhibitor and the appearance of maximal activities of proteinases B and C. The decrease of proteinase B inhibitor activity and the increase of proteinase B activity are markedly retarded by the addition of pepstatin. Because 10-minus 7 M pepstatin completely inhibits proteinase A without affecting proteinase B activity, this is another indication for the role of proteinase A during the activation of proteinase B. Whereas extracts of yeast grown on minimal medium reached maximal activation of proteinases B and C after 20 h of incubation at pH 5.1 and 25 degrees C, extracts of yeast grown on complete medium had to be incubated for about 100 h. In the latter case, the addition of proteinas A results in maximal activation of proteinases B and C and disappearance of proteinase B inhibitor activity only after 10--20 h of incubation. With the optimal conditions, the maximal activities of proteinases A, B and C, as well as of the proteinase B inhibitor, were determined in crude extracts of yeast that had been grown batchwise for different lengths of time either on minimal or on complete medium. Upon incubation, all three proteinases were activated by several times their initial activity. This reflects the existence of proteolytically degradable inhibitors of the three proteinases and together with the above mentioned observations it demonstrates that the "activation" of yeast proteinases A, B and C upon incubation results from the proteolytic digestion of inhibitors rather than from activation of inactive zymogens by limited proteolysis.

  13. Recurrent radio activity in active galactic nuclei

    Directory of Open Access Journals (Sweden)

    Jamrozy M.

    2012-12-01

    Full Text Available There has been a growing body of persuasive evidence to indicate that AGN activity, powered by mass accretion onto a supermassive black hole, can involve multiple episodes. Thus thinking of jet activity as occurring within a unique brief period in the life of a galaxy is no longer valid. The most striking examples of AGNs with recurrent jet activity are the double-double radio sources, which contain two or more pairs of distinct lobes on the opposite sides of a parent optical object. On the other hand, we have now conclusive arguments that galaxy mergers and interactions are principal triggers for AGNs. Quite a number of examples of powerful radio sources hosted by galaxies with peculiar optical morphologies (tails, shells, dust-lanes, etc. can be cited to support such a scenario. The structure and spectra of extended radio emission from radio galaxies, with sizes ranging up to a few Mpc, can provide a lot of information on the history of the central AGN activity, while the spectral and dynamical ages of these extended radio lobes could be used to constrain the time scales of recurrent AGN activity.

  14. Active ageing technologies

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    the elderly. As part of this rearticulation of old age, many new technologies take form. This paper uses a wide concept of technologies (devices, regimes, strategies and ways of doing) and argues that technologies form active aging subjectivities, and on the other hand, that these subjectivities...... ‘sites of active aging’ in Denmark. By presenting three technologies of active aging (billiards at an activity center for elderly persons, dancing tiles for rehabilitation after falls and an online fitness community for elderly persons) the paper suggests that active aging is more than regimes...

  15. Accessibility, activity participation and location of activities

    DEFF Research Database (Denmark)

    Næss, Petter

    2006-01-01

    By investigating relationships between residential location and the availability of facilities, location of activities, trip distances, activity participation and trip frequencies, this paper seeks to contribute to a more detailed and nuanced understanding of the relationships between residential...... outweigh each other. However, differences in trip distances due to the location of the dwelling relative to concentrations of facilities translate into substantially longer total travelling distances among suburbanites than among inner-city residents....... location and the amount of daily-life travel in an urban region. The empirical data are from a comprehensive study of residential location and travel in Copenhagen Metropolitan Area. Differences between inner- and outer-area residents in activity frequencies and trip frequencies are modest and partly...

  16. Sympathetic neural control of indoleamine metabolism in the rat pineal gland

    Science.gov (United States)

    Lynch, H. J.; Hsuan, M.; Wurtman, R. J.

    1975-01-01

    The mechanisms responsible for the acceleration in rat pineal biosynthetic activity in response to prolonged exposure to darkness or to immobilization were investigated in animals whose pineals were surgically denervated. Some animals were adrenalectomized to remove one potential source of circulating catecholamines, and some were subjected to a partial chemical sympathectomy accomplished by a series of intravenous injections of 6-hydroxydopamine. Results suggest that N-acetyltransferase (NAT) activity can be enhanced either by release of norepinephrine from sympathetic terminals within the pineal or from sympathetic nerve terminals elsewhere. The stress of immobilization stimulates the pineal by increasing circulating catecholamines. Photic control of pineal function requires intact pineal sympathetic innervation, since the onset of darkness apparently does not cause a sufficient rise in circulating catecholamines to stimulate the pineal. The present studies suggest that nonspecific stress triggers increased biosynthesis and secretion of melatonin; it is possible that this hormone may participate in mechanisms of adaptation.

  17. Marine Biology Activities. Ocean Related Curriculum Activities.

    Science.gov (United States)

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  18. Active knee joint flexibility and sports activity

    DEFF Research Database (Denmark)

    Hahn, Thomas; Foldspang, Anders; Vestergaard, E

    1999-01-01

    was significantly higher in women than in men and significantly positively associated with weekly hours of swimming and weekly hours of competitive gymnastics. Active knee flexion was significantly positively associated with participation in basketball, and significantly negatively associated with age and weekly...

  19. [Biomedical activity of biosurfactants].

    Science.gov (United States)

    Krasowska, Anna

    2010-07-23

    Biosurfactants, amphiphilic compounds, synthesized by microorganisms have surface, antimicrobial and antitumor properties. Biosurfactants prevent adhesion and biofilms formation by bacteria and fungi on various surfaces. For many years microbial surfactants are used as antibiotics with board spectrum of activity against microorganisms. Biosurfactants act as antiviral compounds and their antitumor activities are mediated through induction of apoptosis. This work presents the current state of knowledge related to biomedical activity of biosurfactants.

  20. CDBG Economic Development Activity

    Data.gov (United States)

    Department of Housing and Urban Development — CDBG activity related to economic development, including commercial or industrial rehab, commercial or industrial land acquisition, commercial or industrial...

  1. CDBG Housing Activity

    Data.gov (United States)

    Department of Housing and Urban Development — CDBG activity related to housing, including multifamily rehab, housing services, code enforcement, operation and repair of foreclosed property and public housing...

  2. CDBG Public Services Activity

    Data.gov (United States)

    Department of Housing and Urban Development — CDBG activity related to public services, including senior services, legal services, youth services, employment training, health services, homebuyer counseling, food...

  3. Lung cancer in Asian women-the environment and genes.

    Science.gov (United States)

    Lam, Wah Kit

    2005-09-01

    The mortality rate of lung cancer in Asian women has increased significantly in the past few decades. Environmental factors include tobacco smoke (active and environmental), other indoor pollutions (cooking oil vapours, coal burning, fungus spores), diet, and infections. Active tobacco smoking is not the major factor. The relative risk of lung cancer among non-smoking women ever exposed to environmental smoke from their husbands was 1.20 from a meta-analysis. Cooking oil vapours associated with high temperature wok cooking and indoor coal burning for heating and cooking in unvented homes, particularly in rural areas, are risk factors for Chinese women. Chronic benign respiratory diseases due to the fungus Microsporum canis probably accounts for the high incidence of lung cancer in northern Thai women at Sarapee. Diets rich in fruits, leafy green vegetables, and vitamin A are protective, while cured meat (Chinese sausage, pressed duck and cured pork), deep-fried cooking, and chili increased the risk. Tuberculosis is associated with lung cancer. Also, a Taiwanese study showed that the odds ratio of papillomavirus (HPV) 16/18 infection in non-smoking female lung cancer patients was 10.1, strongly suggesting a causative role. Genetic factors have also been studied in Chinese women, including human leucocyte antigens, K-ras oncogene activation, p53 mutation, polymorphisms of phase I activating enzymes (cytochrome P450, N-acetyltransferase slow acetylator status), and phase II detoxifying enzymes (glutathione-S-transferases, N-acetyltransferase rapid acetylator status). New molecular screening technology would facilitate identification of molecular targets for future studies. The interaction between environmental and genetic factors should also be further elucidated.

  4. Activity Book: Ocean Ecology.

    Science.gov (United States)

    Learning, 1992

    1992-01-01

    Presents a collection of activities to help elementary students study ocean ecology. The activities have students investigate ocean inhabitants, analyze animal adaptations, examine how temperature and saltiness affect ocean creatures, and learn about safeguarding the sea. Student pages offer reproducible learning sheets. (SM)

  5. Reflections on Activity Theory

    Science.gov (United States)

    Bakhurst, David

    2009-01-01

    It is sometimes suggested that activity theory represents the most important legacy of Soviet philosophy and psychology. But what exactly "is" activity theory? The canonical account in the West is given by Engestrom, who identifies three stages in the theory's development: from Vygotsky's insights, through Leontiev's articulation of the…

  6. The Activity of Play

    DEFF Research Database (Denmark)

    Pichlmair, Martin

    2016-01-01

    This paper presents Activity Theory as a framework for understanding the action of playing games with the intention of building a foundation for the creation of new game design tools and methods. Activity Theory, an epistemological framework rooted in Soviet psychology of the first half of the 20...

  7. Physical Activity Questionnaire

    Directory of Open Access Journals (Sweden)

    Kostencka Alicja

    2016-11-01

    Full Text Available Study aim: The aim of the study was to determine the weekly energy expenditure measuring MET/min/week based on data collected through the Canada Fitness Survey (CFS, according to the classification used in the International Physical Activity Questionnaire (IPAQ, and to verify the adopted method to assess the level of physical activity in students of physical education.

  8. Active and Healthy Schools

    Science.gov (United States)

    Ball, Stephen; Kovarik, Jessica; Leidy, Heather

    2015-01-01

    The Active and Healthy School Program (AHS) can be used to alter the culture and environment of a school to help children make healthier choices. The purpose of this study was to determine the effectiveness of AHS to increase physical activity while decreasing total screen time, increase healthy food choices, and improve knowledge about physical…

  9. Activating Event Knowledge

    Science.gov (United States)

    Hare, Mary; Jones, Michael; Thomson, Caroline; Kelly, Sarah; McRae, Ken

    2009-01-01

    An increasing number of results in sentence and discourse processing demonstrate that comprehension relies on rich pragmatic knowledge about real-world events, and that incoming words incrementally activate such knowledge. If so, then even outside of any larger context, nouns should activate knowledge of the generalized events that they denote or…

  10. Emotionally Intense Science Activities

    Science.gov (United States)

    King, Donna; Ritchie, Stephen; Sandhu, Maryam; Henderson, Senka

    2015-01-01

    Science activities that evoke positive emotional responses make a difference to students' emotional experience of science. In this study, we explored 8th Grade students' discrete emotions expressed during science activities in a unit on Energy. Multiple data sources including classroom videos, interviews and emotion diaries completed at the end of…

  11. Peak Longevity Physical Activity

    Science.gov (United States)

    People who engage in three to five times the recommended minimum level of leisure-time physical activity derive the greatest benefit in terms of mortality reduction when compared with people who do not engage in leisure-time physical activity.

  12. Activities of the ILO.

    Science.gov (United States)

    Labour Education, 1984

    1984-01-01

    Seven articles on International Labour Organization (ILO) activities cover study groups at ILO headquarters, a Philippine rural workers seminar, women's participation in Central American union activities, worksite courses in India, and seminars and symposia in Cape Verde, Mauritius, and Sierra Leone. (SK)

  13. Choreography of AMPK activation.

    Science.gov (United States)

    Langendorf, Christopher G; Kemp, Bruce E

    2015-01-01

    A recent study published in Cell Research by Li and colleagues reports a detailed biophysical and structural study of AMPK's intra-molecular interactions during activation. By employing subunit tagging and proximity analysis with the aid of AlphaScreen instrumentation, Li et al. add to our understanding of the choreography of activation of AMPK by both nucleotides and phosphorylation.

  14. Obesity, Physical Activity - Children.

    Science.gov (United States)

    Gilliam, Thomas B.

    Childhood obesity starts at a very early age, and preventive measures taken early enough may retard the development of fat cells. It appears that physical activity plays an important role in reducing obesity. The activity program must start early, in preschool days. It is felt that screening children for obesity when they first enter school and…

  15. Active at Any Size

    Science.gov (United States)

    ... go to the gym all the time to benefit from being active. To make physical activity more fun, try something you enjoy doing, such as dancing to the radio or taking a yoga class with friends. Many people find they start ...

  16. Global physical activity levels

    DEFF Research Database (Denmark)

    Hallal, Pedro C; Andersen, Lars Bo; Bull, Fiona C

    2012-01-01

    To implement effective non-communicable disease prevention programmes, policy makers need data for physical activity levels and trends. In this report, we describe physical activity levels worldwide with data for adults (15 years or older) from 122 countries and for adolescents (13-15-years-old) ...

  17. Biomedical activity of biosurfactants

    OpenAIRE

    Anna Krasowska

    2010-01-01

    Biosurfactants, amphiphilic compounds, synthesized by microorganisms have surface, antimicrobial and antitumor properties. Biosurfactants prevent adhesion and biofilms formation by bacteria and fungi on various surfaces. For many years microbial surfactants are used as antibiotics with board spectrum of activity against microorganisms. Biosurfactants act as antiviral compounds and their antitumor activities are mediated through induction of apoptosis. This work presents the current state of k...

  18. Activity-based design

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2006-01-01

    : what you can do depends upon where you are. Finally, human and automatic machinery alternate in filling certain roles in the activity: sometime the officer maintains the course, sometimes the autopilot. Such activities require us to rethink the traditional oppositions between communication...

  19. Determinants of Physical Activity in Active and Low-Active, Sixth Grade African-American Youth.

    Science.gov (United States)

    Trost, Stewart G.; Pate, Russell R.; Ward, Dianne S.; Saunders, Ruth; Riner, William

    1999-01-01

    Compared determinants of physical activity in active and low-active African-American sixth graders, surveying students and making objective assessments of physical activity over seven days. Results indicated that physical activity self-efficacy, beliefs about physical activity outcomes, involvement in community-based physical activity, perception…

  20. Homeobox genes and melatonin synthesis: regulatory roles of the cone-rod homeobox transcription factor in the rodent pineal gland.

    Science.gov (United States)

    Rohde, Kristian; Møller, Morten; Rath, Martin Fredensborg

    2014-01-01

    Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod homeobox (CRX) transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.

  1. Chronic exposure to ELF fields may induce depression

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B.W.

    1988-01-01

    Exposure to extremely-low-frequency (ELF) electric or magnetic fields has been postulated as a potentially contributing factor in depression. Epidemiologic studies have yielded positive correlations between magnetic- and/or electric-field strengths in local environments and the incidence of depression-related suicide. Chronic exposure to ELF electric or magnetic fields can disrupt normal circadian rhythms in rat pineal serotonin-N-acetyltransferase activity as well as in serotonin and melatonin concentrations. Such disruptions in the circadian rhythmicity of pineal melatonin secretion have been associated with certain depressive disorders in human beings. In the rat, ELF fields may interfere with tonic aspects of neuronal input to the pineal gland, giving rise to what may be termed functional pinealectomy. If long-term exposure to ELF fields causes pineal dysfunction in human beings as it does in the rat, such dysfunction may contribute to the onset of depression or may exacerbate existing depressive disorders. 85 references.

  2. Homeobox Genes and Melatonin Synthesis: Regulatory Roles of the Cone-Rod Homeobox Transcription Factor in the Rodent Pineal Gland

    Directory of Open Access Journals (Sweden)

    Kristian Rohde

    2014-01-01

    Full Text Available Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based induction of Aanat transcription. However, additional transcriptional control mechanisms exist. Homeobox genes, which are generally known to encode transcription factors controlling developmental processes, are also expressed in the mature rodent pineal gland. Among these, the cone-rod homeobox (CRX transcription factor is believed to control pineal-specific Aanat expression. Based on recent advances in our understanding of Crx in the rodent pineal gland, we here suggest that homeobox genes play a role in adult pineal physiology both by ensuring pineal-specific Aanat expression and by facilitating cAMP response element-based circadian melatonin production.

  3. Intracellular light-activation of riboswitch activity.

    Science.gov (United States)

    Walsh, Steven; Gardner, Laura; Deiters, Alexander; Williams, Gavin J

    2014-06-16

    By combining a riboswitch with a cell-permeable photocaged small-molecule ligand, an optochemical gene control element was constructed that enabled spatial and temporal control of gene expression in bacterial cells. The simplicity of this strategy, coupled with the ability to create synthetic riboswitches with tailored ligand specificities and output in a variety of microorganisms, plants, and fungi might afford a general strategy to photocontrol gene expression in vivo. The ability to activate riboswitches by using light enables the interrogation and manipulation of a wide range of biological processes with high precision, and will have broad utility in the regulation of artificial genetic circuits.

  4. Biological activities of alginate.

    Science.gov (United States)

    Ueno, Mikinori; Oda, Tatsuya

    2014-01-01

    To gain insight into the structure-activity relationship of alginate, we examined the effect of alginates with varying molecular weights and M/G ratio on murine macrophage cell line, RAW264.7 cells in terms of induction of tumor necrosis factor-α (TNF-α) secretion. Among the alginates tested, alginate with the highest molecular weight (MW 38,000, M/G 2.24) showed the most potent TNF-α-inducing activity. Alginates having higher M/G ratio tended to show higher activity. These results suggest that molecular size and M/G ratio are important structural parameters influencing the TNF-α-inducing activity. Interestingly, enzymatic depolymerization of alginate with bacterial alginate lyase resulted in dramatic increase in the TNF-α-inducing activity. The higher activity of enzymatically digested alginate oligomers to induce nitric oxide production from RAW264.7 cells than alginate polymer was also observed. On the other hand, alginate polymer and oligomer showed nearly equal hydroxyl radical scavenging activities.

  5. Emotionally Intense Science Activities

    Science.gov (United States)

    King, Donna; Ritchie, Stephen; Sandhu, Maryam; Henderson, Senka

    2015-08-01

    Science activities that evoke positive emotional responses make a difference to students' emotional experience of science. In this study, we explored 8th Grade students' discrete emotions expressed during science activities in a unit on Energy. Multiple data sources including classroom videos, interviews and emotion diaries completed at the end of each lesson were analysed to identify individual student's emotions. Results from two representative students are presented as case studies. Using a theoretical perspective drawn from theories of emotions founded in sociology, two assertions emerged. First, during the demonstration activity, students experienced the emotions of wonder and surprise; second, during a laboratory activity, students experienced the intense positive emotions of happiness/joy. Characteristics of these activities that contributed to students' positive experiences are highlighted. The study found that choosing activities that evoked strong positive emotional experiences, focused students' attention on the phenomenon they were learning, and the activities were recalled positively. Furthermore, such positive experiences may contribute to students' interest and engagement in science and longer term memorability. Finally, implications for science teachers and pre-service teacher education are suggested.

  6. Active optical zoom system

    Science.gov (United States)

    Wick, David V.

    2005-12-20

    An active optical zoom system changes the magnification (or effective focal length) of an optical imaging system by utilizing two or more active optics in a conventional optical system. The system can create relatively large changes in system magnification with very small changes in the focal lengths of individual active elements by leveraging the optical power of the conventional optical elements (e.g., passive lenses and mirrors) surrounding the active optics. The active optics serve primarily as variable focal-length lenses or mirrors, although adding other aberrations enables increased utility. The active optics can either be LC SLMs, used in a transmissive optical zoom system, or DMs, used in a reflective optical zoom system. By appropriately designing the optical system, the variable focal-length lenses or mirrors can provide the flexibility necessary to change the overall system focal length (i.e., effective focal length), and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses. The active optics can provide additional flexibility by allowing magnification to occur anywhere within the FOV of the system, not just on-axis as in a conventional system.

  7. A universe of activities

    Science.gov (United States)

    Armentia, J.; Jáuregui, F.; Gordón, N.; Manzanal, R.

    Since its opening back in november 1993 the Planetarium of Pamplona has gone a long way creating activities related to teaching and communicating Astronomy, Science and other areas of what we call Culture. In this poster we present a summary of some of the most relevant activities that have had an special relevance throughout these years. We will refer to our “School of Stars” in which more than 400 000 students have already been involved and other activities that have been very appreciated by our visitors.

  8. Physics of solar activity

    Science.gov (United States)

    Sturrock, Peter A.

    1993-01-01

    The aim of the research activity was to increase our understanding of solar activity through data analysis, theoretical analysis, and computer modeling. Because the research subjects were diverse and many researchers were supported by this grant, a select few key areas of research are described in detail. Areas of research include: (1) energy storage and force-free magnetic field; (2) energy release and particle acceleration; (3) radiation by nonthermal electrons; (4) coronal loops; (5) flare classification; (6) longitude distributions of flares; (7) periodicities detected in the solar activity; (8) coronal heating and related problems; and (9) plasma processes.

  9. China's Space Activities

    Institute of Scientific and Technical Information of China (English)

    China National Space Administration

    2004-01-01

    @@ Currently, space activities are very active around the world. Space technologies continuously expand to various areas of human activities, and space technology and applications are becoming an indispensable part of modern information society,while the development of space science brings a brand-new view to the development of science and technology. The development of space law is not only an important approach to improving people' s quality of lives, expanding the living space of human being, and exploiting new resources, but also an important symbol of the comprehensive strength and civilization of a nation.

  10. Active Directory cookbook

    CERN Document Server

    Hunter, Laura

    2008-01-01

    When you need practical hands-on support for Active Directory, the updated edition of this extremely popular Cookbook provides quick solutions to more than 300 common (and uncommon) problems you might encounter when deploying, administering, and automating Microsoft's network directory service. For the third edition, Active Directory expert Laura E. Hunter offers troubleshooting recipes based on valuable input from Windows administrators, in addition to her own experience. You'll find solutions for the Lightweight Directory Access Protocol (LDAP), ADAM (Active Directory Application Mode), m

  11. Creative activity and inclusion

    Directory of Open Access Journals (Sweden)

    Shemanov A.Yu.

    2013-09-01

    Full Text Available The aim of the article was to analyze the inclusion potential of art creative activity, namely of theatre performance, in people with disabilities. The article provides examples of disagreements in understanding the significance of these art activities for exercising the rights of people with disabilities to contribute to culture and art and some problems arising here. The conclusion is made that theatre art performed by people with disabilities is gradually changing its function: from being a means of self-affirmation to the determination of its specific place in overall theatre process. These changes confirm the inclusion potential of theatre art activity.

  12. Active Packaging Coatings

    Directory of Open Access Journals (Sweden)

    Luis J. Bastarrachea

    2015-11-01

    Full Text Available Active food packaging involves the packaging of foods with materials that provide an enhanced functionality, such as antimicrobial, antioxidant or biocatalytic functions. This can be achieved through the incorporation of active compounds into the matrix of the commonly used packaging materials, or by the application of coatings with the corresponding functionality through surface modification. The latter option offers the advantage of preserving the packaging materials’ bulk properties nearly intact. Herein, different coating technologies like embedding for controlled release, immobilization, layer-by-layer deposition, and photografting are explained and their potential application for active food packaging is explored and discussed.

  13. Creating Art Appreciation Activities.

    Science.gov (United States)

    Heidt, Ann H.

    1986-01-01

    The experiences of college students enrolled as majors in elementary education in designing art appreciation activities for use in elementary classrooms are described. The college students had no art background. (RM)

  14. Active flows on trees

    CERN Document Server

    Forrow, Aden; Dunkel, Jörn

    2016-01-01

    Coherent, large scale dynamics in many nonequilibrium physical, biological, or information transport networks are driven by small-scale local energy input. We introduce and explore a generic model for compressible active flows on tree networks. In contrast to thermally-driven systems, active friction selects discrete states with only a small number of oscillation modes activated at distinct fixed amplitudes. This state selection interacts with graph topology to produce different localized dynamical time scales in separate regions of large networks. Using perturbation theory, we systematically predict the stationary states of noisy networks and find good agreement with a Bayesian state estimation based on a hidden Markov model applied to simulated time series data on binary trees. While the number of stable states per tree scales exponentially with the number of edges, the mean number of activated modes in each state averages $\\sim 1/4$ the number of edges. More broadly, these results suggest that the macrosco...

  15. Tanzania - Kigoma Solar Activity

    Data.gov (United States)

    Millennium Challenge Corporation — The performance evaluation of the Kigoma solar activity was designed to answer questions about the implementation of the program and about outcomes that may have...

  16. Physical activity: genes & health

    CERN Multimedia

    2002-01-01

    Carl Johan SUNDBERG is an Associate Professor in Physiology and Licenced Physician. His research focus is Molecular mechanisms involved in the adaptation of human skeletal muscle to physical activity.

  17. Homebuyer Activities Report

    Data.gov (United States)

    Department of Housing and Urban Development — This monthly report is an Excel spreadsheet. PJs can use this report to view homebuyer activities with the 2012 or 2013 program year in IDIS that are in final draw,...

  18. Math Lab Activities

    Science.gov (United States)

    Brumbaugh, Douglas K.; Hynes, Michael C.

    1974-01-01

    The goals, objects, materials and grade levels are specified in this description of a laboratory activity involving analytic geometry concepts. Students mark out bicycle gymkhana courses in which directions to participants are given by Cartesian coordinates. (JP)

  19. PRCR Classes and Activities

    Data.gov (United States)

    Town of Cary, North Carolina — This data is specific to Parks and Recreation classes, workshops, and activities within the course catalog. It contains an entry for upcoming classes.*This data set...

  20. Habitats, activities, and signs

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh; Brynskov, Martin

    2004-01-01

    Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational, ......, and pragmatic, 2) proposes a notation, and 3) sketches a method and exemplifies areas of application using authentic cases from hospital work, primary school education, the maritime domain, and other areas......Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational...

  1. Active Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Ek, Sara

    This thesis deals with the fabrication and characterization of active photonic crystal waveguides, realized in III-V semiconductor material with embedded active layers. The platform offering active photonic crystal waveguides has many potential applications. One of these is a compact photonic...... crystal semiconductor optical amplier. As a step towards such a component, photonic crystal waveguides with a single quantum well, 10 quantum wells and three layers of quantum dots are fabricated and characterized. An experimental study of the amplied spontaneous emission and a implied transmission...... due to photonic crystal dispersion. The observations are explained by the enhancement of net gain by light slow down. Another application based on active photonic crystal waveguides is micro lasers. Measurements on quantum dot micro laser cavities with different mirror configurations and photonic...

  2. CDBG Public Improvements Activity

    Data.gov (United States)

    Department of Housing and Urban Development — CDBG activity related to public improvements, including senior centers, youth centers, parks, street improvements, water/sewer improvements, child care centers, fire...

  3. Extravehicular activity technology discipline

    Science.gov (United States)

    Webbon, Bruce W.

    1990-01-01

    Viewgraphs on extravehicular activity technology discipline for Space Station Freedom are presented. Topics covered include: extravehicular mobility unit; airlock and EMU support equipment; tools, mobility aids, and workstations; and telerobotic work aids interfaces.

  4. MARIHUANA ACTIVITY OF CANNABINOL.

    Science.gov (United States)

    Loewe, S

    1945-12-14

    Cannabinol, generally believed to be an inert component of hemp oil, is shown to have marihuana activity. The significance of this observation with regard to the relationship between structure and mamactivity in the class of cannabinols is discussed.

  5. OTI Activity Database

    Data.gov (United States)

    US Agency for International Development — OTI's worldwide activity database is a simple and effective information system that serves as a program management, tracking, and reporting tool. In each country,...

  6. Vessel Activity Record

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Vessel Activity Record is a bi-weekly spreadsheet that shows the status of fishing vessels. It records whether fishing vessels are fishing without an observer...

  7. RAVEN Quality Assurance Activities

    Energy Technology Data Exchange (ETDEWEB)

    Cogliati, Joshua Joseph [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    This report discusses the quality assurance activities needed to raise the Quality Level of Risk Analysis in a Virtual Environment (RAVEN) from Quality Level 3 to Quality Level 2. This report also describes the general RAVEN quality assurance activities. For improving the quality, reviews of code changes have been instituted, more parts of testing have been automated, and improved packaging has been created. For upgrading the quality level, requirements have been created and the workflow has been improved.

  8. Intercreativity: Mapping Online Activism

    Science.gov (United States)

    Meikle, Graham

    How do activists use the Internet? This article maps a wide range of activist practice and research by applying and developing Tim Berners-Lee's concept of ‘intercreativity' (1999). It identifies four dimensions of Net activism: intercreative texts, tactics, strategies and networks. It develops these through examples of manifestations of Net activism around one cluster of issues: support campaigns for refugees and asylum seekers.

  9. TPR And TPR Activities

    Institute of Scientific and Technical Information of China (English)

    宋丽萍

    2008-01-01

    This paper presents the definition of Total Physical Response(TPR),elaborates the process and the principles of it 80 that more and more TPR activities can be created according to them.The use of TPR shows us an interesting and effective way of teaching and learning English.TPR activities are interesting,challenging and motivating that almost all the students enjoy them.

  10. Toroidal optical activity

    CERN Document Server

    Raybould, T A; Papasimakis, N; Kuprov, I; Youngs, I; Chen, W T; Tsai, D P; Zheludev, N I

    2015-01-01

    Optical activity is ubiquitous across natural and artificial media and is conventionally understood in terms of scattering from electric and magnetic moments. Here we demonstrate experimentally and confirm numerically a type of optical activity that cannot be attributed to electric and magnetic multipoles. We show that our observations can only be accounted for by the inclusion of the toroidal dipole moment, the first term of the recently established peculiar family of toroidal multipoles.

  11. Phytase activity in lichens.

    Science.gov (United States)

    Higgins, Niall F; Crittenden, Peter D

    2015-10-01

    Phytase activity was investigated in 13 lichen species using a novel assay method. The work tested the hypothesis that phytase is a component of the suite of surface-bound lichen enzymes that hydrolyse simple organic forms of phosphorus (P) and nitrogen (N) deposited onto the thallus surface. Hydrolysis of inositol hexaphosphate (InsP6 , the substrate for phytase) and appearance of lower-order inositol phosphates (InsP5 -InsP1 ), the hydrolysis products, were measured by ion chromatography. Phytase activity in Evernia prunastri was compared among locations with contrasting rates of N deposition. Phytase activity was readily measurable in epiphytic lichens (e.g. 11.3 μmol InsP6 hydrolysed g(-1)  h(-1) in Bryoria fuscescens) but low in two terricolous species tested (Cladonia portentosa and Peltigera membranacea). Phytase and phosphomonoesterase activities were positively correlated amongst species. In E. prunastri both enzyme activities were promoted by N enrichment and phytase activity was readily released into thallus washings. InsP6 was not detected in tree canopy throughfall but was present in pollen leachate. Capacity to hydrolyse InsP6 appears widespread amongst lichens potentially promoting P capture from atmospheric deposits and plant leachates, and P cycling in forest canopies. The enzyme assay used here might find wider application in studies on plant root-fungal-soil systems.

  12. Antimicrobial activity of flavonoids.

    Science.gov (United States)

    Cushnie, T P Tim; Lamb, Andrew J

    2005-11-01

    Flavonoids are ubiquitous in photosynthesising cells and are commonly found in fruit, vegetables, nuts, seeds, stems, flowers, tea, wine, propolis and honey. For centuries, preparations containing these compounds as the principal physiologically active constituents have been used to treat human diseases. Increasingly, this class of natural products is becoming the subject of anti-infective research, and many groups have isolated and identified the structures of flavonoids possessing antifungal, antiviral and antibacterial activity. Moreover, several groups have demonstrated synergy between active flavonoids as well as between flavonoids and existing chemotherapeutics. Reports of activity in the field of antibacterial flavonoid research are widely conflicting, probably owing to inter- and intra-assay variation in susceptibility testing. However, several high-quality investigations have examined the relationship between flavonoid structure and antibacterial activity and these are in close agreement. In addition, numerous research groups have sought to elucidate the antibacterial mechanisms of action of selected flavonoids. The activity of quercetin, for example, has been at least partially attributed to inhibition of DNA gyrase. It has also been proposed that sophoraflavone G and (-)-epigallocatechin gallate inhibit cytoplasmic membrane function, and that licochalcones A and C inhibit energy metabolism. Other flavonoids whose mechanisms of action have been investigated include robinetin, myricetin, apigenin, rutin, galangin, 2,4,2'-trihydroxy-5'-methylchalcone and lonchocarpol A. These compounds represent novel leads, and future studies may allow the development of a pharmacologically acceptable antimicrobial agent or class of agents.

  13. Hypoglycemic Activity of Jatrorrhizine

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The hypoglycemic activity and its mechanism of Jatrorrhizine (Jat) were studied. The normal mice and alloxan-induced hyperglycemic mice were given with different doses of Jat. Blood glucose and liver glycogen levels were determined by spectrophotometry with glucose-oxidase and iodine reagents respectively. The levels of blood lactic acid (LC) and liver lactate dehydrogenase (LDH) activity were measured to explore the effect of Jat on anaerobic glycolysis. Succinate dehydrogenase (SDH) activity in liver was measured to evaluate the effect of Jat on aerobic glycolysis in liver. It was found that Jat (50 mg/kg, 100 mg/kg) could significantly decrease blood glucose level in a dose- and time-dependent manner in both normal and alloxan-diabetic mice, increase the activity of SDH, but had no significant effects on the LC level and LDH activity. Jat could significantly reduce the content of liver glycogen in normal mice. Moreover, Jat could inhibit the platelet aggregation in rabbits in vitro in a dose-effect relationship. It was concluded that Jat induced the pronounced decrease in blood glucose in normal and hyperglycemic mice. The hypoglycemic activity of Jat may be attributed to the enhancement of aerobic glycolysis.

  14. Alteration of the oxygen-dependent reactivity of de novo Due Ferri proteins

    Science.gov (United States)

    Reig, Amanda J.; Pires, Marcos M.; Snyder, Rae Ana; Wu, Yibing; Jo, Hyunil; Kulp, Daniel W.; Butch, Susan E.; Calhoun, Jennifer R.; Szyperski, Thomas G.; Solomon, Edward I.; Degrado, William F.

    2012-11-01

    De novo proteins provide a unique opportunity to investigate the structure-function relationships of metalloproteins in a minimal, well-defined and controlled scaffold. Here, we describe the rational programming of function in a de novo designed di-iron carboxylate protein from the Due Ferri family. Originally created to catalyse the O2-dependent, two-electron oxidation of hydroquinones, the protein was reprogrammed to catalyse the selective N-hydroxylation of arylamines by remodelling the substrate access cavity and introducing a critical third His ligand to the metal-binding cavity. Additional second- and third-shell modifications were required to stabilize the His ligand in the core of the protein. These structural changes resulted in at least a 106-fold increase in the relative rate between the arylamine N-hydroxylation and hydroquinone oxidation reactions. This result highlights the potential for using de novo proteins as scaffolds for future investigations of the geometric and electronic factors that influence the catalytic tuning of di-iron active sites.

  15. Psychomotor activities with seniors

    Directory of Open Access Journals (Sweden)

    Jitka Kopřivová

    2015-07-01

    Full Text Available BACKGROUND: Given that the population all over the world is aging, it is necessary to fi nd ways to help maintain or improve the quality of life of seniors. The main goal of this paper is to show how appropriate physical activity programs contribute to the improvement of the functionality and psychosocial wellbeing of seniors. We are particularly interested in the possibilities of preserving self-suffi ciency and self-service, independence and the ability to perform everyday activities. One of the most eff ective forms of physical activity is psychomotr activity.OBJECTIVE: The aim of our paper is to present basic information concerning the meaning and the application of the psychomotr activities in intervention movement programmes in order to improve seniors’ life quality.METHODS: We defi ne the term psychomotr activities according to Adamírová (1995 and Novotná (2010. In this paper we present some results of research that stress the positive eff ect of psychomotor exercises and games on the life satisfaction of the elderly (Stará 2011; Stará & Kopřivová, 2011.DESCRIPTION: According to the results of our research and practical experience gained from working with the elderly it is strongly recommended to include suitable psychomotor exercises and games focusing on the development of manual dexterity in training programs in order to improve the balance abilities and the psychosocial area. In terms of prevention, because of the growing number of neurological disorders at an old age it is appropriate to include psychomotor exercises that encourage the development of cognitive functions in the physical interventions.CONCLUSION: We were able to positively infl uence the emotional aspect from performing physical activities, to enhance self-esteem of the exercising subjects and to create new social relationships. Motion programs, which also included psychomotor exercises and games, had a positive eff ect on the physical assessment of the

  16. Antimutagenic activity of spearmint.

    Science.gov (United States)

    Yu, Tian-Wei; Xu, Meirong; Dashwood, Roderick H

    2004-01-01

    The antimutagenic activity of spearmint (Mentha spicata), a popular food flavoring agent, was studied in the Salmonella assay. Spearmint leaves were brewed in hot water for 5 min at concentrations up to 5% (w/v), and the water extracts were tested against the direct-acting mutagens 4-nitro-1,2-phenylenediamine (NPD) and 2-hydroxyamino-3-methyl-3H-imidazo[4,5-f]quinoline (N-OH-IQ) using Salmonella typhimurium strain TA98. Nontoxic concentrations of spearmint extract inhibited the mutagenic activity of N-OH-IQ in a concentration-dependent fashion, but had no effect against NPD. These experiments by design focused on the water extract consumed commonly as an herbal tea, but chloroform and methanol extracts of spearmint also possessed antimutagenic activity against N-OH-IQ. Water extract of spearmint inhibited the mutagenic activity of the parent compound, 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ), in the presence of rat liver S9; however, the concentration for 50% inhibition (IC50) against IQ was approximately 10-fold higher than in assays with N-OH-IQ minus S9. At concentrations similar to those used in the Salmonella assays, spearmint extract inhibited two of the major enzymes that play a role in the metabolic activation of IQ, namely, cytochromes P4501A1 and 1A2, based on ethoxyresorufin O-deethylase and methoxyresorufin O-demethylase assays in vitro. In vivo, rats were given spearmint water extract (2%; w/v) as the sole source of drinking fluid before, during, and after 2-week treatment with IQ; colonic aberrant crypt foci were inhibited significantly at 8 weeks (P < 0.05, compared with rats given IQ alone). Collectively, these findings suggest that spearmint tea protects against IQ and possibly other heterocyclic amines through inhibition of carcinogen activation and via direct effects on the activated metabolite(s).

  17. ACTIVATION ENERGY OF DESORPTION OF DIBENZOFURAN ON ACTIVATED CARBONS

    Institute of Scientific and Technical Information of China (English)

    LI Xiang; LI Zhong; XI Hongxia; LUO Lingai

    2004-01-01

    Three kinds of commercial activated carbons, such as Norit RB1, Monolith and Chemviron activated carbons, were used as adsorbents for adsorption of dibenzofuran. The average pore size and specific surface area of these activated carbons were measured. Temperature Programmed Desorption (TPD) experiments were conducted to measure the TPD curves of dibenzofuran on the activated carbons, and then the activation energy for desorption of dibenzofuran on the activated carbons was estimated. The results showed that the Chemviron and the Norit RB1 activated carbon maintained higher specific surface area and larger micropore pore volume in comparison with the Monolith activated carbon, and the activation energy for the desorption of dibenzofuran on these two activated carbons was higher than that on the Monolith activated carbon. The smaller the pore of the activated carbon was, the higher the activated energy of dibenzofuran desorption was.

  18. Interpreting EEG alpha activity.

    Science.gov (United States)

    Bazanova, O M; Vernon, D

    2014-07-01

    Exploring EEG alpha oscillations has generated considerable interest, in particular with regards to the role they play in cognitive, psychomotor, psycho-emotional and physiological aspects of human life. However, there is no clearly agreed upon definition of what constitutes 'alpha activity' or which of the many indices should be used to characterize it. To address these issues this review attempts to delineate EEG alpha-activity, its physical, molecular and morphological nature, and examine the following indices: (1) the individual alpha peak frequency; (2) activation magnitude, as measured by alpha amplitude suppression across the individual alpha bandwidth in response to eyes opening, and (3) alpha "auto-rhythmicity" indices: which include intra-spindle amplitude variability, spindle length and steepness. Throughout, the article offers a number of suggestions regarding the mechanism(s) of alpha activity related to inter and intra-individual variability. In addition, it provides some insights into the various psychophysiological indices of alpha activity and highlights their role in optimal functioning and behavior.

  19. Active flows on trees

    Science.gov (United States)

    Forrow, Aden; Woodhouse, Francis G.; Dunkel, Jörn

    2016-11-01

    Coherent, large scale dynamics in many nonequilibrium physical, biological, or information transport networks are driven by small-scale local energy input. We introduce and explore a generic model for compressible active flows on tree networks. In contrast to thermally-driven systems, active friction selects discrete states with only a small number of oscillation modes activated at distinct fixed amplitudes. This state selection can interact with graph topology to produce different localized dynamical time scales in separate regions of large networks. Using perturbation theory, we systematically predict the stationary states of noisy networks. Our analytical predictions agree well with a Bayesian state estimation based on a hidden Markov model applied to simulated time series data on binary trees. While the number of stable states per tree scales exponentially with the number of edges, the mean number of activated modes in each state averages 1 / 4 the number of edges. More broadly, these results suggest that the macroscopic response of active networks, from actin-myosin networks in cells to flow networks in Physarum polycephalum, can be dominated by a few select modes.

  20. Active noise control primer

    CERN Document Server

    Snyder, Scott D

    2000-01-01

    Active noise control - the reduction of noise by generating an acoustic signal that actively interferes with the noise - has become an active area of basic research and engineering applications. The aim of this book is to present all of the basic knowledge one needs for assessing how useful active noise control will be for a given problem and then to provide some guidance for designing, setting up, and tuning an active noise-control system. Written for students who have no prior knowledge of acoustics, signal processing, or noise control but who do have a reasonable grasp of basic physics and mathematics, the book is short and descriptive. It leaves for more advanced texts or research monographs all mathematical details and proofs concerning vibrations, signal processing and the like. The book can thus be used in independent study, in a classroom with laboratories, or in conjunction with a kit for experiment or demonstration. Topics covered include: basic acoustics; human perception and sound; sound intensity...

  1. Software Activation Using Multithreading

    Directory of Open Access Journals (Sweden)

    Jianrui Zhang

    2012-11-01

    Full Text Available Software activation is an anti-piracy technology designed to verify that software products have been legitimately licensed. Activation should be quick and simple while simultaneously being secure and protecting customer privacy. The most common form of software activation is for the user to enter a legitimate product serial number. However, software activation based on serial numbers appears to be weak, since cracks for many programs are readily available on the Internet. Users can employ such cracks to bypass software activation.Serial number verification logic usually executes sequentially in a single thread. Such an approach is relatively easy to break since attackers can trace the code to understand how the logic works. In this paper, we develop a practical multi-threaded verification design. Our results show that by proper use of multi-threading, the amount of traceable code in a debugger can be reduced to a low percentage of the total and the traceable code in each run can differ as well. This makes it significantly more difficult for an attacker to reverse engineer the code as a means of bypassing a security check. Finally, we attempt to quantify the increased effort needed to break our verification logic.

  2. Chromatin as active matter

    Science.gov (United States)

    Agrawal, Ankit; Ganai, Nirmalendu; Sengupta, Surajit; Menon, Gautam I.

    2017-01-01

    Active matter models describe a number of biophysical phenomena at the cell and tissue scale. Such models explore the macroscopic consequences of driving specific soft condensed matter systems of biological relevance out of equilibrium through ‘active’ processes. Here, we describe how active matter models can be used to study the large-scale properties of chromosomes contained within the nuclei of human cells in interphase. We show that polymer models for chromosomes that incorporate inhomogeneous activity reproduce many general, yet little understood, features of large-scale nuclear architecture. These include: (i) the spatial separation of gene-rich, low-density euchromatin, predominantly found towards the centre of the nucleus, vis a vis. gene-poor, denser heterochromatin, typically enriched in proximity to the nuclear periphery, (ii) the differential positioning of individual gene-rich and gene-poor chromosomes, (iii) the formation of chromosome territories, as well as (iv), the weak size-dependence of the positions of individual chromosome centres-of-mass relative to the nuclear centre that is seen in some cell types. Such structuring is induced purely by the combination of activity and confinement and is absent in thermal equilibrium. We systematically explore active matter models for chromosomes, discussing how our model can be generalized to study variations in chromosome positioning across different cell types. The approach and model we outline here represent a preliminary attempt towards a quantitative, first-principles description of the large-scale architecture of the cell nucleus.

  3. [Inflammasome: activation mechanisms].

    Science.gov (United States)

    Suárez, Raibel; Buelvas, Neudo

    2015-03-01

    Inflammation is a rapid biologic response of the immune system in vascular tissues, directed to eliminate stimuli capable of causing damage and begin the process of repair. The macromolecular complexes known as "inflammasomes" are formed by a receptor, either NOD (NLR) or ALR, the receptor absent in melanoma 2 (AIM2). In addition, the inflammasome is formed by the speck-like protein associated to apoptosis (ASC) and procaspase-1, that may be activated by variations in the ionic and intracellular and extracellular ATP concentrations; and the loss of stabilization of the fagolisosomme by internalization of insoluble crystals and redox mechanisms. As a result, there is activation of the molecular platform and the processing of inflammatory prointerleukins to their active forms. There are two modalities of activation of the inflammasome: canonical and non-canonical, both capable of generating effector responses. Recent data associate NLRP 3, IL-1β and IL-18 in the pathogenesis of a variety of diseases, including atherosclerosis, type II diabetes, hyperhomocysteinemia, gout, malaria and hypertension. The inflammasome cascade is emerging as a new chemotherapeutic target in these diseases. In this review we shall discuss the mechanisms of activation and regulation of the inflammasome that stimulate, modulate and resolve inflammation.

  4. Regulating prefrontal cortex activation

    DEFF Research Database (Denmark)

    Aznar, Susana; Klein, Anders Bue

    2013-01-01

    of emotion-based actions, such as addiction and other impulse-related behaviors. In this review, we give an overview of the 5-HT2A receptor distribution (neuronal, intracellular, and anatomical) along with its functional and physiological effect on PFC activation, and how that relates to more recent findings......The prefrontal cortex (PFC) is involved in mediating important higher-order cognitive processes such as decision making, prompting thereby our actions. At the same time, PFC activation is strongly influenced by emotional reactions through its functional interaction with the amygdala...... is highly expressed in the prefrontal cortex areas, playing an important role in modulating cortical activity and neural oscillations (brain waves). This makes it an interesting potential pharmacological target for the treatment of neuropsychiatric modes characterized by lack of inhibitory control...

  5. IHY activities in Brazil

    Science.gov (United States)

    Dal Lago, Alisson

    The International Heliophysical Year is a program of international scientific colaboration planned to be held in the period from 2007-2009. Many brazilian institutions have shown interest in participating in the IHY activities. All of them provided information about their instrumental facilities and contact person. A list of institutions and their information is shown in the Latin-American IHY webpage (http://www.alage.org/IHYLA/ihyla.html), hosted by the Latin American Association on Space Geophysics - ALAGE. IHY Brazilian activities are being conducted in close colaboration with Latin-American Institutions. Five Coordinated Investigation programs (CIPs) have been proposed by scientists from brazilian institutions. Recentely, in February 2008, there has been the Latin American IHY School in Sao Paulo (Brazil), with the participation of 80 students from Brazil, Argentina, Peru, Mexico and Cuba. In this work, a report on the brazilian activities will be presented.

  6. Lesion activity assessment

    DEFF Research Database (Denmark)

    Ekstrand, K R; Zero, D T; Martignon, S;

    2009-01-01

    . The literature suggests that there is a fair agreement between visual/tactile external scripts of caries and the severity/depth of the lesion. The reproducibility of the different systems is, in general, substantial. No single clinical predictor is able to reliably assess activity. However, a combination......This chapter focusses on the probability of a caries lesion detected during a clinical examination being active (progressing) or arrested. Visual and tactile methods to assess primary coronal lesions and primary root lesions are considered. The evidence level is rated as low (R...... in response to cariogenic plaque as well as lesion arrest. Based on this understanding, different clinical scoring systems have been developed to assess the severity/depth and activity of lesions. A recent system has been devised by the International Caries Detection and Assessment System Committee...

  7. Active Elbow Orthosis

    Directory of Open Access Journals (Sweden)

    Tomas Ripel

    2014-09-01

    Full Text Available This paper presents a novel approach to the design of a motorized rehabilitation device – active elbow orthosis (AEO – inspired by the principles of robotic exoskeletons. The device is currently designed for the elbow joint, but can be easily modified for other joints as well. AEO determines the motion activity of the patient using a strain gauge and utilizes this measurement to control the actuator that drives the forearm part of the orthosis. Patient activity level is related to a free arm measurement obtained via a calibration procedure prior to the exercise. A high-level control module offers several types of exercises mimicking the physiotherapist. The device was successfully verified by tests on a number of patients, resulting in extended range of elbow-joint motion.

  8. Adapted Active Appearance Models

    Directory of Open Access Journals (Sweden)

    Renaud Séguier

    2009-01-01

    Full Text Available Active Appearance Models (AAMs are able to align efficiently known faces under duress, when face pose and illumination are controlled. We propose Adapted Active Appearance Models to align unknown faces in unknown poses and illuminations. Our proposal is based on the one hand on a specific transformation of the active model texture in an oriented map, which changes the AAM normalization process; on the other hand on the research made in a set of different precomputed models related to the most adapted AAM for an unknown face. Tests on public and private databases show the interest of our approach. It becomes possible to align unknown faces in real-time situations, in which light and pose are not controlled.

  9. Correlates of physical activity

    DEFF Research Database (Denmark)

    Bauman, Adrian E; Reis, Rodrigo S; Sallis, James F

    2012-01-01

    that age, sex, health status, self-efficacy, and motivation are associated with physical activity. Ecological models take a broad view of health behaviour causation, with the social and physical environment included as contributors to physical inactivity, particularly those outside the health sector......Physical inactivity is an important contributor to non-communicable diseases in countries of high income, and increasingly so in those of low and middle income. Understanding why people are physically active or inactive contributes to evidence-based planning of public health interventions, because......, such as urban planning, transportation systems, and parks and trails. New areas of determinants research have identified genetic factors contributing to the propensity to be physically active, and evolutionary factors and obesity that might predispose to inactivity, and have explored the longitudinal tracking...

  10. General human activity patterns

    CERN Document Server

    Mollgaard, Anders; Mathiesen, Joachim

    2016-01-01

    We investigate the dynamics and interplay between human communication, movement, and social proximity by analyzing data collected from smartphones distributed among 638 individuals. The main question we consider is: to what extent do individuals act according to patterns shared across an entire population? Based on statistics of the entire population, we successfully predict 71\\% of the activity and 85\\% of the inactivity involved in communication, movement, and social proximity. We find that individual level statistics only result in marginally better predictions, indicating a high degree of shared activity patterns across the population. Finally, we predict short-term activity patterns using a generalized linear model, which suggests that a simple linear description might be sufficient to explain a wide range of actions, whether they be of social or of physical character.

  11. SCOR announces new activities

    Science.gov (United States)

    Urban, Edward R., Jr.

    Roger Revelle had many good ideas during his long and productive career. One of them came to fruition in 1957 in the form of the Scientific Committee on Oceanic Research (SCOR), which the International Council for Science created as its first interdisciplinary body, to promote international activities in oceanography. Revelle served as SCOR's first president from 1957 to 1960. SCOR offers opportunities for scientists from different countries to cooperate in planning and executing international programs in ocean sciences. Over its 44 years in existence, SCOR has sponsored 120 working groups and has actively participated in many of the major international oceanographic projects. Thirty-six nations presently participate as SCOR members.

  12. Actively coupled optical waveguides

    OpenAIRE

    Alexeeva, N. V.; Barashenkov, I. V.; Rayanov, K.; Flach, S.

    2013-01-01

    We consider light propagation through a pair of nonlinear optical waveguides with absorption, placed in a medium with power gain. The active medium boosts the in-phase component of the overlapping evanescent fields of the guides, while the nonlinearity of the guides couples it to the damped out-of-phase component creating a feedback loop. As a result, the structure exhibits stable stationary and oscillatory regimes in a wide range of gain-loss ratios. We show that the pair of actively-coupled...

  13. Actively coupled optical waveguides

    Science.gov (United States)

    Alexeeva, N. V.; Barashenkov, I. V.; Rayanov, K.; Flach, S.

    2014-01-01

    We consider light propagation through a pair of nonlinear optical waveguides with absorption, placed in a medium with power gain. The active medium boosts the in-phase component of the overlapping evanescent fields of the guides, while the nonlinearity of the guides couples it to the damped out-of-phase component creating a feedback loop. As a result, the structure exhibits stable stationary and oscillatory regimes in a wide range of gain-loss ratios. We show that the pair of actively coupled (AC) waveguides can act as a stationary or integrate-and-fire comparator sensitive to tiny differences in their input powers.

  14. Antibacterial Activity of Grepafloxacin

    Directory of Open Access Journals (Sweden)

    B Wiedemann

    1998-01-01

    Full Text Available Grepafloxin has an extremely broad spectrum of activity. Its activity against Gram-positive bacteria exceeds that of currently available quinolones. Grepafloxacin-resistant mutants seem to occur less frequently than ciprofloxacin - or ofloxacin-resistant mutants, and the increase in minimum inhibitory concentration (MIC against the former mutants is less than that of the latter. This applies only to the relative differences (in dilution steps; the absolute values are similar. Grepafloxacin kills Gram-positive bacteria at concentrations little above the MIC. Its pharmacodynamic profile against pneumococci is promising, favouring use of this drug for respiratory tract infections.

  15. Measuring children's physical activity

    DEFF Research Database (Denmark)

    Schneller, Mikkel Bo; Bentsen, Peter; Nielsen, Glen

    2017-01-01

    INTRODUCTION: Accelerometer-based physical activity monitoring has become the method of choice in many large-scale physical activity (PA) studies. However, there is an ongoing debate regarding the placement of the device, the determination of device wear time, and how to solve a lack of participant...... on the thigh (n=903) and one on the lower back (n= 856), for up to ten consecutive days. Participants were instructed not to reattach an accelerometer should it fall off. Simple and multiple linear regression were used to determine associations between accelerometer wear time and age, sex, BMI percentiles...

  16. BlmB and TlmB provide resistance to the bleomycin family of antitumor antibiotics by N-acetylating metal-free bleomycin, tallysomycin, phleomycin, and zorbamycin.

    Science.gov (United States)

    Coughlin, Jane M; Rudolf, Jeffrey D; Wendt-Pienkowski, Evelyn; Wang, Liyan; Unsin, Claudia; Galm, Ute; Yang, Dong; Tao, Meifeng; Shen, Ben

    2014-11-11

    The bleomycin (BLM) family of glycopeptide-derived antitumor antibiotics consists of BLMs, tallysomycins (TLMs), phleomycins (PLMs), and zorbamycin (ZBM). The self-resistant elements BlmB and TlmB, discovered from the BLM- and TLM-producing organisms Streptomyces verticillus ATCC15003 and Streptoalloteichus hindustanus E465-94 ATCC31158, respectively, are N-acetyltransferases that provide resistance to the producers by disrupting the metal-binding domain of the antibiotics required for activity. Although each member of the BLM family of antibiotics possesses a conserved metal-binding domain, the structural differences between each member, namely, the bithiazole moiety and C-terminal amine of BLMs, have been suggested to instill substrate specificity within BlmB. Here we report that BlmB and TlmB readily accept and acetylate BLMs, TLMs, PLMs, and ZBM in vitro but only in the metal-free forms. Kinetic analysis of BlmB and TlmB reveals there is no strong preference or rate enhancement for specific substrates, indicating that the structural differences between each member of the BLM family play a negligible role in substrate recognition, binding, or catalysis. Intriguingly, the zbm gene cluster from Streptomyces flavoviridis ATCC21892 does not contain an N-acetyltransferase, yet ZBM is readily acetylated by BlmB and TlmB. We subsequently established that S. flavoviridis lacks the homologue of BlmB and TlmB, and ZbmA, the ZBM-binding protein, alone is sufficient to provide ZBM resistance. We further confirmed that BlmB can indeed confer resistance to ZBM in vivo in S. flavoviridis, introduction of which into wild-type S. flavoviridis further increases the level of resistance.

  17. Antifungal activity of diethyldithiocarbamate.

    Science.gov (United States)

    Allerberger, F; Reisinger, E C; Söldner, B; Dierich, M P

    1989-10-01

    Sodium diethyldithiocarbamate (DTC) was evaluated for its ability to combat four different species of fungi in vitro. Using a microtiter-broth-dilution method we were able to demonstrate an antifungal activity against Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus and Mucor mucedo in doses achievable by intravenous administration in man.

  18. Atherosclerosis and Physical Activity

    OpenAIRE

    Al-Mamari, Ali

    2009-01-01

    Atherosclerosis and coronary heart disease have been considered as major health problem worldwide. Abnormalities in lipids and lipoprotein metabolism and impairment of endothelial function have been implicated as the main contributing factors in atherosclerosis and its progression. Physical activity has been recognized as a preventive measure for atherosclerosis.

  19. Bonus Activity Book.

    Science.gov (United States)

    Learning, 1993

    1993-01-01

    Elementary level activity book presents suggestions for teaching students about endangered and threatened species worldwide. Students learn about what is causing the rapid extinction rate and what needs to be done. They also discover the value of rainforests and why conservationists are fighting to save them. (SM)

  20. Asteroseismic stellar activity relations

    CERN Document Server

    Bonanno, A; Karoff, C

    2014-01-01

    In asteroseismology an important diagnostic of the evolutionary status of a star is the small frequency separation which is sensitive to the gradient of the mean molecular weight in the stellar interior. It is thus interesting to discuss the classical age-activity relations in terms of this quantity. Moreover, as the photospheric magnetic field tends to suppress the amplitudes of acoustic oscillations, it is important to quantify the importance of this effect by considering various activity indicators. We propose a new class of age-activity relations that connects the Mt. Wilson $S$ index and the average scatter in the light curve with the small frequency separation and the amplitude of the p-mode oscillations. We used a Bayesian inference to compute the posterior probability of various empirical laws for a sample of 19 solar-like active stars observed by the Kepler telescope. We demonstrate the presence of a clear correlation between the Mt. Wilson $S$ index and the relative age of the stars as indicated by ...

  1. [Biological activity of Spirulina].

    Science.gov (United States)

    Blinkova, L P; Gorobets, O B; Baturo, A P

    2001-01-01

    In this review information of Spirulina platensis (SP), a blue-green alga (photosynthesizing cyanobacterium) having diverse biological activity is presented. Due to high content of highly valuable proteins, indispensable amino acids, vitamins, beta-carotene and other pigments, mineral substances, indispensable fatty acids and polysaccharides, PS has been found suitable for use as bioactive additive. SP produces an immunostimulating effect by enhancing the resistance of humans, mammals, chickens and fish to infections, the capacity of influencing hemopoiesis, stimulating the production of antibodies and cytokines. Under the influence of SP macrophages, T and B cells are activated. SP sulfolipids have proved to be effective against HIV. Preparations obtained from SP biomass have also been found active against herpesvirus, cytomegalovirus, influenza virus, etc. SP extracts are capable in inhibiting cancerogenesis. SP preparations are regarded as functional products contributing to the preservation of the resident intestinal microflora, especially lactic acid bacilli and bifidobacteria, and to a decrease in the level of Candida albicans. The biological activity of SP with respect to microorganisms holds good promise for using these microalgae as components of culture media.

  2. Activation force splines

    DEFF Research Database (Denmark)

    Engell-Nørregård, Morten Pol; Erleben, Kenny

    dimensional 2D/3D deformable model. Our activation splines are easy to set up and can be used for physics based animation of deformable models such as snake motion and locomotion of characters. Our approach generalises easily to both 2D and 3D simulations and is applicable in physics based games or animations...

  3. Mechanism of charity activity

    Directory of Open Access Journals (Sweden)

    Roman B. Golovkin

    2015-12-01

    Full Text Available Objective to establish the essential properties of the mechanism of charitable activities and to formulate the concept of quotmechanism of charitable activityquot. Methods the objective of the study is achieved using the complex of methods which are based on the interaction of dialectical and metaphysical analysis the epistemological properties of which allowed to reveal various aspects of the charitable activities mechanism functioning taking into account the principles of comprehensiveness complexity specificity and objectivity of the research. Results the rules are stated of using the term quotmechanismquot to characterize actions of state and law the essence of the charity mechanism is defined the definition of quotthe mechanism of charitable activity quot is formulated. Scientific novelty for the first time at theoretical level in legal science the definition of quotthe mechanism of charitable activityquot is formulated and its essential properties are set. Practical significance the research will contribute to improving the legal regulation in the field of philanthropy as well as to improving the efficiency and quality of charitable activity in the Russian Federation. nbsp

  4. Active surveillance: Oncologic outcome

    NARCIS (Netherlands)

    L.D.F. Venderbos (Lionne); L.P. Bokhorst (Leonard); C.H. Bangma (Chris); M.J. Roobol-Bouts (Monique)

    2013-01-01

    textabstractPURPOSE OF REVIEW: To give insight into recent literature (during the past 12-18 months) reporting on oncologic outcomes of men on active surveillance. RECENT FINDINGS: From recent published trials comparing radical prostatectomy vs. watchful waiting, we learn that radical treatment only

  5. Low activity aluminum blanket

    Energy Technology Data Exchange (ETDEWEB)

    Benenati, R.; Tichler, P.; Powell, J.R.

    1976-03-01

    The basic design of the breeding blanket consists of cylindrical aluminium canisters filled with a ceramic bed of moderating, shielding, and breeding materials all suitably cooled. A technical analysis of the blanket for an EPR design is given. Activation studies are presented. The effect of pulsed magnetic fields on module structure is investigated. (MOW)

  6. Seismology of active stars

    NARCIS (Netherlands)

    Hekker, S.; García, R.A.

    2012-01-01

    In this review we will discuss the current standing and open questions of seismology in active stars. With the longer photometric time series data that are, and will become, available from space-missions such as Kepler we foresee significant progress in our understanding of stellar internal structur

  7. 'Active' Thin Sections

    NARCIS (Netherlands)

    De Rooij, M.R.; Bijen, J.M.J.M.

    1999-01-01

    Optical microscopy using thin sections has become more and more important over the last decade to study concrete. Unfortunately, this technique is not capable of studying actually hydrating cement paste. At Delft University of Technology a new technique has been developed using 'active' thin section

  8. Sexual activity and aging.

    Science.gov (United States)

    Ni Lochlainn, Mary; Kenny, Rose Anne

    2013-08-01

    Sexuality is an important component of emotional and physical intimacy that men and women experience throughout their lives. Research suggesting that a high proportion of men and women remain sexually active well into later life refutes the prevailing myth that aging and sexual dysfunction are inexorably linked. Age-related physiological changes do not render a meaningful sexual relationship impossible or even necessarily difficult. Many of these physiological changes are modifiable. There are various therapeutic options available to patients to achieve maximum sexual capacity in old age. This article reviews the prevalence of sexual activity among older adults, the problems these adults encounter with sexual activity, and the role of the health care professional in addressing these problems. The physiological sex-related changes that occur as part of the normal aging process in men and women are reviewed, as well as the effect of age-related physical and psychological illness on sexual function. The attitudes and perceptions of the media and general public toward sexual activity and aging are summarized. An understanding of the sexual changes that accompany the aging process may help general practitioners and other doctors to give practical and useful advice on sexuality as well as refute the misconception that aging equates to celibacy. A thorough awareness of this aspect of older people's quality of life can raise meaningful expectations for aging patients.

  9. Elusive active galactic nuclei

    NARCIS (Netherlands)

    Maiolino, R; Comastri, A; Gilli, R; Nagar, NM; Bianchi, S; Boker, T; Colbert, E; Krabbe, A; Marconi, A; Matt, G; Salvati, M

    2003-01-01

    A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically 'elusive'. X-ray observations are an optimal tool to identify this class of objects. We combine new Chandra observations with archival X-ray data in order to obtai

  10. Activated Sludge Rheology

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Horn, Willi; Helmus, Frank

    2013-01-01

    Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and filtr...

  11. Regional Activities Division. Papers.

    Science.gov (United States)

    International Federation of Library Associations, The Hague (Netherlands).

    Papers on library network activities in Canada, the Third World, Japan, Malaysia, Brazil, and Sweden which were presented at the 1982 International Federation of Library Associations (IFLA) conference include: (1) "Canada: A Voluntary and Flexible Network," a review by Guy Sylvestre of the political, social, and economic structures affecting…

  12. Active Math Learning

    DEFF Research Database (Denmark)

    The presentation is concerned with general course planning philosophy and a specific case study (boomerang flight geometro-dynamics) for active learning of mathematics via computer assisted and hands-on unfolding of first principles - in this case the understanding of rotations and Eulers equatio...

  13. Marketing coprovided activities.

    Science.gov (United States)

    Dickerson, Pamela S

    2014-05-01

    Coproviding is a wonderful way for two or more organizations to work together to provide continuing nursing education. To be transparent to the learners, marketing materials identify the parties involved and prominently note the name of the organization accountable for developing the activity and awarding the contact hours.

  14. An electrochemical active valve

    NARCIS (Netherlands)

    Neagu, C.R.; Gardeniers, J.G.E.; Elwenspoek, M.; Kelly, J.J.

    1997-01-01

    A novel electrochemical microactuator was developed, which operates as an active valve. The microactuator consists of an electrochemical cell and a membrane that deflects because of the pressure of oxygen gas generated by electrolysis. Relatively large pressures (up to tens of bars) can be reached w

  15. Access and Fishing Activities

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2015-01-01

    In this chapter, I look at the implications of transferable quotas on the organization of production; that is, how fishing activities are structured around access to the individual and transferable quotas and how, in turn, the quotas structure the production. Therefore, this chapter will give...

  16. Grooming. Learning Activity Package.

    Science.gov (United States)

    Stark, Pamela

    This learning activity package on grooming for health workers is one of a series of 12 titles developed for use in health occupations education programs. Materials in the package include objectives, a list of materials needed, information sheets, reviews (self evaluations) of portions of the content, and answers to reviews. These topics are…

  17. CMMs Development Activities

    Institute of Scientific and Technical Information of China (English)

    HU Jun; HU Yefa; HUANG Anyi

    2006-01-01

    The coordinate measuring machine (CMM) has been an important role in the digital manufacturing. This paper reviews CMM early stage development history and current activities. The authors provide some ideas about the areas that academic research can help to the CMMs development.

  18. Shark Tagging Activities.

    Science.gov (United States)

    Current: The Journal of Marine Education, 1998

    1998-01-01

    In this group activity, children learn about the purpose of tagging and how scientists tag a shark. Using a cut-out of a shark, students identify, measure, record data, read coordinates, and tag a shark. Includes introductory information about the purpose of tagging and the procedure, a data sheet showing original tagging data from Tampa Bay, and…

  19. Antimalarial activity of cedronin.

    Science.gov (United States)

    Moretti, C; Deharo, E; Sauvain, M; Jardel, C; David, P T; Gasquet, M

    1994-06-01

    Cedronin was isolated from Simaba cedron Planchon (Simaroubaceae), a species popularly believed in South America to have antimalarial properties. It was examined for in vitro and in vivo antimalarial activities and for cytotoxicity against KB cells. Experimental results showed that cedronin was active against chloroquine-sensitive and resistant strain, with an IC50 of 0.25 micrograms/ml (0.65 mumol/ml). It was also found to be active in vivo against Plasmodium vinkei with an IC50 of 1.8 mg/kg (4.7 nM/kg) in the classic 4-day test. Cedronin belongs to the small group of quassinoids with a C19 basic skeleton and shows a rather low cytotoxicity against KB cells (IC50 = 4 micrograms/ml, 10.4 microM) as compared with C20 biologically active quassinoids; however its toxic/therapeutic ratio (10/1.8) remains lower than chloroquine (10/0.5).

  20. Interdisciplinary Astronomy Activities

    Science.gov (United States)

    Nerantzis, Nikolaos; Mitrouda, Aikaterini; Reizopoulou, Ioanna; Sidiropoulou, Eirini; Hatzidimitriou, Antonios

    2016-04-01

    On November 9th, 2015, three didactical hours were dedicated to Interdisciplinary Astronomy Activities (http://wp.me/p6Hte2-1I). Our students and their teachers formed three groups and in rotation, were engaged with the following activities: (a) viewing unique images of the Cosmos in the mobile planetarium STARLAB (http://www.planitario.gr/tholos-starlab-classic-standard.html), (b) watching the following videos: Journey to the end of the universe (https://youtu.be/Ufl_Nwbl8xs), Rosetta update (https://youtu.be/nQ9ivd7wv30), The Solar System (https://youtu.be/d66dsagrTa0), Ambition the film (https://youtu.be/H08tGjXNHO4) in the school's library. Students and teachers were informed about our solar system, the Rosetta mission, the universe, etc. and (c) tactile activities such as Meet our home and Meet our neighbors (http://astroedu.iau.org, http://nuclio.org/astroneighbours/resources) and the creation of planets' 3D models (Geology-Geography A' Class Student's book, pg.15). With the activities above we had the pleasure to join the Cosmic Light Edu Kit / International Year of Light 2015 program. After our Interdisciplinary Astronomy Activities, we did a "small" research: our students had to fill an evaluation about their educational gains and the results can be found here http://wp.me/p6Hte2-2q. Moreover, we discussed about Big Ideas of Science (http://wp.me/p3oRiZ-dm) and through the "big" impact of the Rosetta mission & the infinity of our universe, we print posters with relevant topics and place them to the classrooms. We thank Rosa Doran (Nuclio - President of the Executive Council) for her continuous assistance and support on innovative science teaching proposals. She is an inspiration.

  1. Activities. Inductive and Deductive Reasoning.

    Science.gov (United States)

    O'Daffer, Phares G.; And Others

    1990-01-01

    Provided are the activity sheets for students and the teaching guide for this middle school geometry activity. Materials, prerequisites, objectives, and procedures are listed. Extension activities are suggested. An answer key is included. (CW)

  2. Is Enhanced Physical Activity Possible Using Active Videogames?

    OpenAIRE

    Baranowski, Tom; Baranowski, Janice; O'Connor, Teresia; Lu, Amy Shirong; Thompson, Debbe

    2012-01-01

    Our research indicated that 10–12-year-old children receiving two active Wii™ (Nintendo®; Nintendo of America, Inc., Redmond, WA) console videogames were no more physically active than children receiving two inactive videogames. Research is needed on how active videogames may increase physical activity.

  3. Is Enhanced Physical Activity Possible Using Active Videogames?

    Science.gov (United States)

    Baranowski, Tom; Baranowski, Janice; O'Connor, Teresia; Lu, Amy Shirong; Thompson, Debbe

    2012-06-01

    Our research indicated that 10-12-year-old children receiving two active Wii(™) (Nintendo(®); Nintendo of America, Inc., Redmond, WA) console videogames were no more physically active than children receiving two inactive videogames. Research is needed on how active videogames may increase physical activity.

  4. Integration of Active Video Games in Extracurricular Activity at Schools

    Science.gov (United States)

    Lee, Jung Eun; Huang, Charles; Pope, Zachary; Gao, Zan

    2015-01-01

    Active video games require players to be physically active. Dance Dance Revolution (DDR) is an interactive dancing game that requires fast-foot movement coordinated with energetic music and visuals. The Wii and Xbox Kinect games have also become good active video games for the promotion of physical activity participation. These games are much more…

  5. Active microchannel heat exchanger

    Science.gov (United States)

    Tonkovich, Anna Lee Y [Pasco, WA; Roberts, Gary L [West Richland, WA; Call, Charles J [Pasco, WA; Wegeng, Robert S [Richland, WA; Wang, Yong [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  6. Nematicidal activity of terpenoids.

    Science.gov (United States)

    Abdel-Rahman, Fawzia H; Alaniz, Nina M; Saleh, Mahmoud A

    2013-01-01

    Thirty four phytoterpenoids were evaluated for their nematicidal effect using the model nematode Caenorhabditis elegans. Nematicidal activities of the tested compounds at concentrations of 50 μg/mL showed wide variation in their effects ranging from no effect, weak, moderate and strong effects. Terpenoids exerting 50% or higher mortality at 50 μg/mL were further tested at five different concentrations to calculate the concentration that will kill 50% of the nematode population (LC(50)). Among the most effective terpenoids were carvacrol, thymol, nerolidol, α-terpinene, geraniol, citronellol, farnesol, limonene, pseudoionone and eugenol in a descending order. These compounds exhibited a dose-dependent effect. The results suggest that the selected monoterpenoids and essential oils with a high concentration of these compounds mayprovide potential natural nematicides and merit further study as botanical nematicides for the control of both plant and animal parasitic nematodes. In general, oxygenated terpenoids and phenolic terpenoids exhibited higher nematicidal activity than hydrocarbons terpenoids.

  7. Apheresis activity in Venezuela.

    Science.gov (United States)

    Saltiel, Christiane

    2005-07-01

    Interest for apheresis activity has been growing in Venezuela. In 1976 there were only a few devices; in 2003, 80 apheresis machines performed 27,675 donor apheresis procedures and 547 therapeutic procedures countrywide. We report the activity at the Metropolitan Blood Bank (the largest one of the country) in the period 1999-2003: 597 therapeutic procedures were performed in 171 patients, during 212 crisis episodes. The average age was 38 +/- 16 years, 65% male and 35% female. Most of the therapeutic procedures were therapeutic plasma exchange for hematology diseases (mainly thrombotic thrombocitopenic purpura and hemophilia inhibitors), including 184 therapeutic procedures with the Autopheresis-C (Baxter Healthcare Corp., Deerfield, IL). Most common adverse effects (3.9%) were hypotension and allergic reactions to the plasma.

  8. Active optical clock

    Institute of Scientific and Technical Information of China (English)

    CHEN JingBiao

    2009-01-01

    This article presents the principles and techniques of active optical clock, a special laser combining the laser physics of one-atom laser, bad-cavity gas laser, super-cavity stabilized laser and optical atomic clock together. As a simple example, an active optical clock based on thermal strontium atomic beam shows a quantum-limited linewidth of 0.51 Hz, which is insensitive to laser cavity-length noise, and may surpass the recorded narrowest 6.7 Hz of Hg ion optical clock and 1.5 Hz of very recent optical lattice clock. The estimated 0.1 Hz one-second instability and 0.27 Hz uncertainty are limited only by the rela-tivistic Doppler effect, and can be improved by cold atoms.

  9. LANSCE Activity Report

    Energy Technology Data Exchange (ETDEWEB)

    Amy Robinson; Audrey Archuleta; Barbara Maes; Dan Strottman; Earl Hoffman; Garth Tietjen; Gene Farnum; Geoff Greene; Joyce Roberts; Ken Johnson; Paul Lewis; Roger Pynn; Stan Schriber; Steve Sterbenz; Steve Wender; Sue Harper

    1999-02-01

    The Los Alamos Neutron Science Center Activity Report describes scientific and technological progress and achievements in LANSCE Division during the period of 1995 to 1998. This report includes a message from the Division Director, an overview of LANSCE, sponsor overviews, research highlights, advanced projects and facility upgrades achievements, experimental and user program accomplishments, news and events, and a list of publications. The research highlights cover the areas of condensed-matter science and engineering, accelerator science, nuclear science, and radiography. This report also contains a compact disk that includes an overview, the Activity Report itself, LANSCE operations progress reports for 1996 and 1997, experiment reports from LANSCE users, as well as a search capability.

  10. Stellar Chromospheric Activity

    Directory of Open Access Journals (Sweden)

    Hall Jeffrey C.

    2008-03-01

    Full Text Available The Sun, stars similar to it, and many rather dissimilar to it, have chromospheres, regions classically viewed as lying above the brilliant photosphere and characterized by a positive temperature gradient and a marked departure from radiative equilibrium. Stellar chromospheres exhibit a wide range of phenomena collectively called activity, stemming largely from the time evolution of their magnetic fields and the mass flux and transfer of radiation through the complex magnetic topology and the increasingly optically thin plasma of the outer stellar atmosphere. In this review, I will (1 outline the development of our understanding of chromospheric structure from 1960 to the present, (2 discuss the major observational programs and theoretical lines of inquiry, (3 review the origin and nature of both solar and stellar chromospheric activity and its relationship to, and effect on, stellar parameters including total energy output, and (4 summarize the outstanding problems today.

  11. Techniques for active passivation

    Energy Technology Data Exchange (ETDEWEB)

    Roscioli, Joseph R.; Herndon, Scott C.; Nelson, Jr., David D.

    2016-12-20

    In one embodiment, active (continuous or intermittent) passivation may be employed to prevent interaction of sticky molecules with interfaces inside of an instrument (e.g., an infrared absorption spectrometer) and thereby improve response time. A passivation species may be continuously or intermittently applied to an inlet of the instrument while a sample gas stream is being applied. The passivation species may have a highly polar functional group that strongly binds to either water or polar groups of the interfaces, and once bound presents a non-polar group to the gas phase in order to prevent further binding of polar molecules. The instrument may be actively used to detect the sticky molecules while the passivation species is being applied.

  12. Cisplatin triggers platelet activation.

    Science.gov (United States)

    Togna, G I; Togna, A R; Franconi, M; Caprino, L

    2000-09-01

    Clinical observations suggest that anticancer drugs could contribute to the thrombotic complications of malignancy in treated patients. Thrombotic microangiopathy, myocardial infarction, and cerebrovascular thrombotic events have been reported for cisplatin, a drug widely used in the treatment of many solid tumours. The aim of this study is to explore in vitro cisplatin effect on human platelet reactivity in order to define the potentially active role of platelets in the pathogenesis of cisplatin-induced thrombotic complications. Our results demonstrate that cisplatin increases human platelet reactivity (onset of platelet aggregation wave and thromboxane production) to non-aggregating concentrations of the agonists involving arachidonic acid metabolism. Direct or indirect activation of platelet phospholipase A(2) appears to be implicated. This finding contributes to a better understanding of the pathogenesis of thrombotic complications occurring during cisplatin-based chemotherapy.

  13. The Active Asteroids

    CERN Document Server

    Jewitt, Dave

    2011-01-01

    Some asteroids eject dust, unexpectedly producing transient, comet-like comae and tails. First ascribed to the sublimation of near-surface water ice, mass losing asteroids (also called "main-belt comets") can in fact be driven by a surprising diversity of mechanisms. In this paper, we consider eleven dynamical asteroids losing mass, in nine of which the ejected material is spatially resolved. We address mechanisms for producing mass loss including rotational instability, impact ejection, electrostatic repulsion, radiation pressure sweeping, dehydration stresses and thermal fracture, in addition to the sublimation of ice. In two objects (133P and 238P) the repetitive nature of the observed activity leaves ice sublimation as the only reasonable explanation while, in a third ((596) Scheila), a recent impact is the cause. Another impact may account for activity in P/2010 A2 but this tiny object can also be explained as having shed mass after reaching rotational instability. Mass loss from (3200) Phaethon is proba...

  14. Myofilament length dependent activation

    Energy Technology Data Exchange (ETDEWEB)

    de Tombe, Pieter P.; Mateja, Ryan D.; Tachampa, Kittipong; Mou, Younss Ait; Farman, Gerrie P.; Irving, Thomas C. (IIT); (Loyola)

    2010-05-25

    The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a beat-to-beat basis. The main cellular mechanism that underlies this phenomenon is an increase in the responsiveness of cardiac myofilaments to activating Ca{sup 2+} ions at a longer sarcomere length, commonly referred to as myofilament length-dependent activation. This review focuses on what molecular mechanisms may underlie myofilament length dependency. Specifically, the roles of inter-filament spacing, thick and thin filament based regulation, as well as sarcomeric regulatory proteins are discussed. Although the 'Frank-Starling law of the heart' constitutes a fundamental cardiac property that has been appreciated for well over a century, it is still not known in muscle how the contractile apparatus transduces the information concerning sarcomere length to modulate ventricular pressure development.

  15. Sesterterpenoids with Anticancer Activity.

    Science.gov (United States)

    Evidente, Antonio; Kornienko, Alexander; Lefranc, Florence; Cimmino, Alessio; Dasari, Ramesh; Evidente, Marco; Mathieu, Véronique; Kiss, Robert

    2015-01-01

    Terpenes have received a great deal of attention in the scientific literature due to complex, synthetically challenging structures and diverse biological activities associated with this class of natural products. Based on the number of C5 isoprene units they are generated from, terpenes are classified as hemi- (C5), mono- (C10), sesqui- (C15), di- (C20), sester- (C25), tri (C30), and tetraterpenes (C40). Among these, sesterterpenes and their derivatives known as sesterterpenoids, are ubiquitous secondary metabolites in fungi, marine organisms, and plants. Their structural diversity encompasses carbotricyclic ophiobolanes, polycyclic anthracenones, polycyclic furan-2-ones, polycyclic hydroquinones, among many other carbon skeletons. Furthermore, many of them possess promising biological activities including cytotoxicity and the associated potential as anticancer agents. This review discusses the natural sources that produce sesterterpenoids, provides sesterterpenoid names and their chemical structures, biological properties with the focus on anticancer activities and literature references associated with these metabolites. A critical summary of the potential of various sesterterpenoids as anticancer agents concludes the review.

  16. Human neutrophil antimicrobial activity.

    Science.gov (United States)

    Thomas, E L; Lehrer, R I; Rest, R F

    1988-01-01

    Polymorphonuclear neutrophilic leukocytes (PMNs) take up opsonized microorganisms into phagosomes that fuse with secretory granules in the PMN cytoplasm to form phagolysosomes. Killing and digestion of microorganisms take place within phagolysosomes. Antimicrobial activities in phagolysosomes are divided into two classes. Oxygen (O2)-dependent mechanisms are expressed when PMNs undergo the "respiratory burst." An NADPH oxidase in the phagolysosome membrane is activated and reduces O2 to superoxide (O2-). O2 reduction is the first step in a series of reactions that produce toxic oxidants. For example, .O2- dismutases to hydrogen peroxide (H2O2), and the azurophil granule enzyme myeloperoxidase catalyzes the oxidation of Cl- by H2O2 to yield hypochlorous acid (HOCl). The reaction of HOCl with ammonia and amines modulates the toxicity of this oxidant. O2-independent antimicrobial mechanisms include the activities of lysosomal proteases, other hydrolytic enzymes, and proteins and peptides that bind to microorganisms and disrupt essential processes or structural components. For example, the bactericidal/permeability-increasing protein, cathepsin G, and the defensins are released into phagolysosomes from the azurophil granules. Proposed mechanisms of action of neutrophil antimicrobial agents, their range of microbial targets, and their possible interactions within phagolysosomes are discussed.

  17. Amphoteric surface active agents

    Directory of Open Access Journals (Sweden)

    Eissa, A.M. F.

    1995-10-01

    Full Text Available 2-[trimethyl ammonium, triethyl ammonium, pyridinium and 2-amino pyridinium] alkanoates, four series of surface active agents containing carbon chain C12, C14, C16 and C18carbon atoms, were prepared. Their structures were characterized by microanalysis, infrared (IR and nuclear magnetic resonance (NMR. Surface and interfacial tension, Krafft point, wetting time, emulsification power, foaming height and critical micelle concentration (cmc were determined and a comparative study was made between their chemical structure and surface active properties. Antimicrobial activity of these surfactants was also determined.

    Se prepararon cuatro series de agentes tensioactivos del tipo 2-[trimetil amonio, trietil amonio, piridinio y 2-amino piridinio] alcanoatos, que contienen cadenas carbonadas con C12, C14, C16 y C18 átomos de carbono.
    Se determinaron la tensión superficial e interfacial, el punto de Krafft, el tiempo humectante, el poder de emulsionamiento, la altura espumante y la concentración critica de miscela (cmc y se hizo un estudio comparativo entre la estructura química y sus propiedades tensioactivas. Se determinó también la actividad antimicrobiana de estos tensioactivos. Estas estructuras se caracterizaron por microanálisis, infrarrojo (IR y resonancia magnética nuclear (RMN.

  18. Thermal activity on Enceladus

    Science.gov (United States)

    Tobie, G.; Besserer, J.; Behounkova, M.; Cadek, O.; Choblet, G.; Sotin, C.

    2009-04-01

    Observations by Cassini have revealed that Enceladus' souh pole is highly active, with jets of icy particles and water vapour emanated from narrow tectonic ridges, called "tiger stripes". This jet activity is associated to a very high thermal emission mainly focused along the tectonic ridges. Heat power required to sustain such an activity is probably related to the dissipation of mechanical energy due to tidal forces exerted by Saturn. However, the dissipation process and its relation to the tectonic features are not clearly established. Both shear heating along the tectonic ridges and viscous dissipation in the convective part of the ice shell could contribute to the energy budget (Nimmo et al. 2007, Tobie et al. 2008). Tobie et al. (2008) pointed out that only interior models with a liquid water layer at depth, covering at least ~2/3 of the southern hemisphere, can explain the observed magnitude of dissipation and its particular location at the south pole. However, the long term stability of such a liquid reservoir remains problematic (Roberts and Nimmo 2007) and the possible link between the liquid reservoir and the surface activities is unknown. Concentration of tidal stresses along the tiger ridges have also been invoked as a mechanism to trigger the eruptive processes (Hurtford et al. 2007, Smith-Konter et al. 2008). However, those models do not take into account a realistic rheological structure for the ice shell when computing the fluctuating stress field. Moreover, the effect of the faults on the background tidal stress is neglected. In particular, low viscosity values are expected to be associated with the shear zone along the tiger stripes and may have a significant impact of the global tidal stress field. In order to self-consistently determine the tidal deformation and its impact on the thermal activity on Enceladus, we are currently developing a 3D model that combines a thermal convection code in spherical geometry (Choblet et al. 2007) and a

  19. Adaptable typologies for active roofs

    NARCIS (Netherlands)

    Quanjel, E.M.C.J.; Zeiler, W.

    2006-01-01

    The main objective of this part of the 6th framework Pan-European EUR-ACTIVE ROOF-er project is to improve the interaction between design participants of dynamic adaptable Active Roofs in product development and Active Roofs from an architects/ customers perspective. Improvements in Active Roof desi

  20. A Novel Method for the Synthesis of High Hindered Iminoesters by the Reaction of Decomposition of Phenyldiazoacetate in the Presence of Rh2(OAc)4 with Arylamines and DEAD

    Institute of Scientific and Technical Information of China (English)

    HUANG,Hao-Xi; WANG,Yuan-Hua; FU,Qing-Quan; LIU,Wei-Jun; CHEN,Zhi-Yong; HU,Wen-Hao

    2004-01-01

    @@ It is well known that iminoesters were condensed by ketoesters with amines, but the procedure to ketoesters require harsh reaction conditions and multi steps. Herein we report a mild and practical one-step approach for the synthesis of iminoesters, especially for the high steric hindered iminoesters. Decomposition of phenyl diazoacetate catalyzed by rhodium acetate with amines to give N-H insertion product has been reported.

  1. 脱氢枞酸芳胺化合物的结构优化及溶致变色行为%Structure Optimization by DFT and Solvatochromism of Series of Dehydroabietic Acid-based Arylamines

    Institute of Scientific and Technical Information of China (English)

    高宏; 陈姗姗; 宋湛谦; 商士斌

    2014-01-01

    Molecular configuration of compounds 5a-5g(methyl 13-(phenyl) aminodeisopropyldehydroabietate(5a),Methyl 13-(4-methoxyphenyl) aminodeisopropyldehydroabietate(5b),methyl 14-(phenyl) aminodehydroabietate(5c),methyl 13-(8-quinoline) aminodeisopropyldehydroabietate(5d),methyl 13-(α-naphthalene)aminodeisopropyldehydroabietate(5e),methyl 13-( p-bromodiphenyl ) aminodeisopropyldehydroabietate ( 5f ), methyl 13-( 4-methylphenyl ) aminodeisopropyldehydroabietate (5g)) and 6a-6h(Methyl 13-[N,N-(4-methoxyphenyl)-phenyl]aminodeisopropyldehydroabietate(6a),methyl 13-[N,N -(p-bromobiphenyl )-phenyl ] aminodeisopropyldehydroabietate ( 6b ), methyl 13-[ N, N-( 4-methylphenyl )-phenyl ] aminodeisopropyldehydroabietate(6c),methyl 13-(N,N-bis-phenyl) aminodeisopropyldehydroabietate(6d),methyl 13-[N, N-bis ( 4-methoxyphenyl )] aminodeisopropyldehydroabietate ( 6e ), methyl 13-[ N, N- ( α-naphthalene )-phenyl ] aminodeisopropyldehydroabietate(6f),methyl 13-[N,N -bis(4-methylphenyl)-phenyl]aminodeisopropyldehydroabietate(6g), methyl 13-[N,N-biphenyl-phenyl]aminodeisopropyldehydroabietate(6h)) were optimized by DFT/B3LYP using Gaussian 03. Their fluorescent properties in solvents of different polarity were analysed, and the relationship between structures and properties were also discussed. The results show that the conjugated length or substituent groups on aryl rings of compounds have big effect on their conjugated degree, and then affect their fluorescent properties. Compounds 5a -5g, 6f, 6b and 6h have deffrent fluorescent emmision wavelengths and all compounds show defferent fluorescent intensity in defferent polarity solvents. Above properties indicate that these compounds have potential to be used as fluorescent probes in different polarity environment.%采用Gaussian 03程序的密度泛函DFT/B3LYP方法,对两个系列脱氢枞酸芳胺化合物5a~5g (13-(苯基)胺基-脱异丙基脱氢枞酸甲酯(5a)、13-(4-甲氧基苯基)胺基-脱异丙基脱氢枞酸甲酯(5b)、14-(苯基)胺基-脱氢枞酸甲酯(5c)、13-(8-喹啉)胺基-脱异丙基脱氢枞酸甲酯(5d)、13-(α-溴萘)胺基-脱异丙基脱氢枞酸甲酯(5e)、13-(对溴联苯基)胺基-脱异丙基脱氢枞酸甲酯(5f)、13-[N-(4-甲基苯基)]胺基-脱异丙基脱氢枞酸甲酯(5g))和6a~6h (13-[N,N-(4-甲氧基苯基)-苯基]胺基-脱异丙基脱氢枞酸甲酯(6a)、13-[N,N-(对溴联苯)-苯基]胺基-脱异丙基脱氢枞酸甲酯(6b)、13-[N,N-(4-甲基苯基)-苯基]胺基-脱异丙基脱氢枞酸甲酯(6c)、13-(N,N-双苯基)胺基-脱异丙基脱氢枞酸甲酯(6d)、13-[N,N-双(4-甲氧基苯基)]胺基-脱异丙基脱氢枞酸甲酯(6e)、13-[N,N-(α-萘)-苯基]胺基-脱异丙基脱氢枞酸甲酯(6f)、13-[N,N-双(4-甲基苯基)]胺基-脱异丙基脱氢枞酸甲酯(6g)、13-(N,N-联苯-苯基)胺基-脱异丙基脱氢枞酸甲酯(6h))的几何构型进行全优化,并研究了它们在5种不同极性溶剂中的荧光发射光谱,探讨了化合物的结构与其发光性能之间的关系。结果表明:芳环的共轭长度及芳环上取代基的种类均影响其共轭程度,从而影响其荧光性能。二芳胺化合物(5a~5g)和三芳胺化合物(6f、6b和6h)在不同极性溶剂中发射波长发生明显位移,所有化合物在不同极性溶剂中具有不同的荧光发射强度,具备作为荧光分子探针探测分子外部环境极性大小的潜能。

  2. The Effect of Donor Group Rigidification on the Electronic and Optical Properties of Arylamine-Based Metal-Free Dyes for Dye-Sensitized Solar Cells: A Computational Study.

    Science.gov (United States)

    Estrella, Liezel L; Balanay, Mannix P; Kim, Dong Hee

    2016-07-28

    One of the most significant aspects in the development of dye-sensitized solar cells is the exploration and design of high-efficiency and low-cost dyes. This paper reports the theoretical design of various triphenylamine analogues, wherein the central nitrogen moiety establishes an sp(2)-hybridization, which endows a significant participation in the charge-transfer properties. Density functional theory (DFT) and time-dependent DFT methodologies were utilized to investigate the geometry, electronic structure, photochemical properties, and electrochemical properties of these dyes. Different exchange-correlation functionals were initially evaluated to establish a proper methodology for calculating the excited-state energy of the reference dye, known as DIA3. Consequently, TD-LC-ωPBE with a damping parameter of 0.175 Bohr(-1) best correlates with the experimental value. Four new dyes, namely, Dhk1, Dhk2, Dhk3, and Dhk4, were designed by modifying the rigidity of the donor moiety. According to the results, altering the type and position of binding in the donor group leads to distinct planarity of the dyes, which significantly affects their properties. The designed Dhk4 dye showed more red-shifted and broadened absorption spectra owing to the enhanced coplanarity between its donor and π-bridge moiety, which brings an advantage for its potential use as sensitizer for photovoltaic applications.

  3. Spontaneous Plasticity of Multineuronal Activity Patterns in Activated Hippocampal Networks

    Directory of Open Access Journals (Sweden)

    Atsushi Usami

    2008-01-01

    Full Text Available Using functional multineuron imaging with single-cell resolution, we examined how hippocampal networks by themselves change the spatiotemporal patterns of spontaneous activity during the course of emitting spontaneous activity. When extracellular ionic concentrations were changed to those that mimicked in vivo conditions, spontaneous activity was increased in active cell number and activity frequency. When ionic compositions were restored to the control conditions, the activity level returned to baseline, but the weighted spatial dispersion of active cells, as assessed by entropy-based metrics, did not. Thus, the networks can modify themselves by altering the internal structure of their correlated activity, even though they as a whole maintained the same level of activity in space and time.

  4. Enzyme Activities in Waste Water and Activated Sludge

    DEFF Research Database (Denmark)

    Nybroe, Ole; Jørgensen, Per Elberg; Henze, Mogens

    1992-01-01

    The purpose of the present study was to evaluate the potential of selected enzyme activity assays to determine microbial abundance and heterotrophic activity in waste water and activated sludge. In waste water, esterase and dehydrogenase activities were found to correlate with microbial abundance...... measured as colony forming units of heterotrophic bacteria. A panel of four enzyme activity assays, α-glucosidase, alanine-aminopeptidase, esterase and dehydrogenase were used to characterize activated sludge and anaerobic hydrolysis sludge from a pilot scale plant. The enzymatic activity profiles were...... distinctly different, suggesting that microbial populations were different, or had different physiological properties, in the two types of sludge. Enzyme activity profiles in activated sludge from four full-scale plants seemed to be highly influenced by the composition of the inlet. Addition of hydrolysed...

  5. Advances in Activity Cliff Research.

    Science.gov (United States)

    Dimova, Dilyana; Bajorath, Jürgen

    2016-05-01

    Activity cliffs, i.e. similar compounds with large potency differences, are of interest from a chemical and informatics viewpoint; as a source of structure-activity relationship information, for compound optimization, and activity prediction. Herein, recent highlights of activity cliff research are discussed including studies that have further extended our understanding of activity cliffs, yielded unprecedented insights, or paved the way for practical applications.

  6. AMS Prototyping Activities

    Science.gov (United States)

    Burleigh, Scott

    2008-01-01

    This slide presentation reviews the activity around the Asynchronous Message Service (AMS) prototype. An AMS reference implementation has been available since late 2005. It is aimed at supporting message exchange both in on-board environments and over space links. The implementation incoroporates all mandatory elements of the draft recommendation from July 2007: (1) MAMS, AMS, and RAMS protocols. (2) Failover, heartbeats, resync. (3) "Hooks" for security, but no cipher suites included in the distribution. The performance is reviewed, and a Benchmark latency test over VxWorks Message Queues is shown as histograms of a count vs microseconds per 1000-byte message

  7. Athena: Assessment Phase Activities

    Science.gov (United States)

    Lumb, David; Ayre, Mark

    2015-09-01

    The Athena mission concept has been proposed by the community in response to science themes of the Hot and Energetic Universe. Unlike other, competitive, mission selection exercises this "Large" class observatory mission has essentially been pre-selected. Nevertheless it has to be demonstrated that Athena meets the programmatic constraints of 1Bn euro cost cap, and a readiness level appropriate for formal mission adoption by the end 2019. This should be confirmed through a Phase A study conducted with two parallel industry activities. We describe the technical and programmatic content of these and latest progress in space and ground segment definition.

  8. Topological Active Volumes

    Directory of Open Access Journals (Sweden)

    Barreira N

    2005-01-01

    Full Text Available The topological active volumes (TAVs model is a general model for 3D image segmentation. It is based on deformable models and integrates features of region-based and boundary-based segmentation techniques. Besides segmentation, it can also be used for surface reconstruction and topological analysis of the inside of detected objects. The TAV structure is flexible and allows topological changes in order to improve the adjustment to object's local characteristics, find several objects in the scene, and identify and delimit holes in detected structures. This paper describes the main features of the TAV model and shows its ability to segment volumes in an automated manner.

  9. System of Volcanic activity

    Directory of Open Access Journals (Sweden)

    P. HÉDERVARI

    1972-06-01

    Full Text Available A comparison is made among the systems of B. G.
    Escher (3, of R. W. van Bemmelen (1 and that of the author (4. In this
    connection, on the basis of Esclier's classification, the terms of "constructiv
    e " and "destructive" eruptions are introduced into the author's system and
    at the same time Escher's concept on the possible relation between the depth
    of magma-chamber and the measure of the gas-pressure is discussed briefly.
    Three complementary remarks to the first paper (4 011 the subject of system
    of volcanic activity are added.

  10. COMPANY ACTIVITY FINANCIAL RISK

    Directory of Open Access Journals (Sweden)

    Caruntu Genu Alexandru

    2012-12-01

    Full Text Available In economic and financial activity, risk is an inherent financial decisions, encountered in daily agenda of managers of companies. Unexpected changes in the price of a product development not only affect the financial results of a company, but can cause even bankruptcy. In fact, the nature of financial decisions involve uncertainty. Financial decisions are made based on cash flows under future contracts, which are par excellence incerte.Activitatea an enterprise that holds any weight in the industry is subject to risks, since it can not predict with certainty different components of its outcome (cost, quantity, price and operating cycle (purchase, processing, sales.

  11. Active galactic nuclei

    CERN Document Server

    Blandford, RD; Woltjer, L

    1990-01-01

    Starting with this volume, the Lecture Notes of the renowned Advanced Courses of the Swiss Society for Astrophysics and Astronomy will be published annually. In each course, three extensive lectures given by leading experts in their respective fields cover different and essential aspects of the subject. The 20th course, held at Les Diablerets in April 1990, dealt with current research on active galactic nuclei; it represents the most up-to-date views on the subject, presented with particular regard for clarity. The previous courses considered a wide variety of subjects, beginning with ""Theory

  12. Active terahertz metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hou-tong [Los Alamos National Laboratory; O' Hara, John F [Los Alamos National Laboratory; Taylor, Antoinette J [Los Alamos National Laboratory

    2009-01-01

    In this paper we present an overview of research in our group in terahertz (THz) metamaterials and their applications. We have developed a series of planar metamaterials operating at THz frequencies, all of which exhibit a strong resonant response. By incorporating natural materials, e.g. semiconductors, as the substrates or as critical regions of metamaterial elements, we are able to effectively control the metamaterial resonance by the application of external stimuli, e.g., photoexcitation and electrical bias. Such actively controllable metamaterials provide novel functionalities for solid-state device applications with unprecedented performance, such as THz spectroscopy, imaging, and many others.

  13. Reuse of activated alumina

    Energy Technology Data Exchange (ETDEWEB)

    Hobensack, J.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Activated alumina is used as a trapping media to remove trace quantities of UF{sub 6} from process vent streams. The current uranium recovery method employs concentrated nitric acid which destroys the alumina pellets and forms a sludge which is a storage and disposal problem. A recently developed technique using a distilled water rinse followed by three dilute acid rinses removes on average 97% of the uranium, and leaves the pellets intact with crush strength and surface area values comparable with new material. Trapping tests confirm the effectiveness of the recycled alumina as UF{sub 6} trapping media.

  14. Diagramming Complex Activities

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2005-01-01

    We increasingly live in heterogeneous ever-changing webs of activities where human actions are intertwined with events created by automatic machines.  In order to make such webs understandable to its human participants, their structure should be represented by displays emphasizing their action as...... aspect. The paper suggests thematic roles as a semantics for actions, argues that a selection of well-known diagramming techniques can be defined within this theory, and uses the theory to discuss new issues related to process control and mobile technology....

  15. Miscarriage and occupational activity

    DEFF Research Database (Denmark)

    Bonde, Jens Peter; Jørgensen, Kristian Tore; Bonzini, Matteo

    2013-01-01

    . METHODS: A search in Medline and EMBASE 1966-2012 identified 30 primary papers reporting the relative risk (RR) of miscarriage according to ≥1 of 5 occupational activities of interest. Following an assessment of completeness of reporting, confounding, and bias, each risk estimate was characterized as more......, N=10). RR for working hours and standing became smaller when analyses were restricted to higher quality studies. CONCLUSIONS: These largely reassuring findings do not provide a strong case for mandatory restrictions in relation to shift work, long working hours, occupational lifting, standing...

  16. Physical activity in elderly

    Directory of Open Access Journals (Sweden)

    Jan Cvecka

    2015-08-01

    Full Text Available Aging is a multifactorial irreversible process associated with significant decline in muscle mass and neuromuscular functions. One of the most efficient methods to counteract age-related changes in muscle mass and function is physical exercise. An alternative effective intervention to improve muscle structure and performance is electrical stimulation. In the present work we present the positive effects of physical activity in elderly and a study where the effects of a 8-week period of functional electrical stimulation and strength training with proprioceptive stimulation in elderly are compared.

  17. Physical Activity in Elderly

    Science.gov (United States)

    Tirpakova, Veronika; Sedliak, Milan; Kern, Helmut; Mayr, Winfried; Hamar, Dušan

    2015-01-01

    Aging is a multifactorial irreversible process associated with significant decline in muscle mass and neuromuscular functions. One of the most efficient methods to counteract age-related changes in muscle mass and function is physical exercise. An alternative effective intervention to improve muscle structure and performance is electrical stimulation. In the present work we present the positive effects of physical activity in elderly and a study where the effects of a 8-week period of functional electrical stimulation and strength training with proprioceptive stimulation in elderly are compared. PMID:26913164

  18. The Active Muon Shield

    CERN Document Server

    Bezshyiko, Iaroslava

    2016-01-01

    In the SHiP beam-dump of the order of 1011 muons will be produced per second. An active muon-shield is used to magnetically deflect these muons out of the acceptance of the spectrom- eter. This note describes how this shield is modelled and optimized. The SHiP spectrometer is being re-optimized using a conical decay-vessel, and utilizing the possibility to magnetize part of the beam-dump shielding iron. A shield adapted to these new conditions is presented which is significantly shorter and lighter than the shield used in the Technical Proposal (TP), while showing a similar performance.

  19. Active galactic nuclei

    CERN Document Server

    Beckmann, Volker

    2012-01-01

    This AGN textbook includes phenomena based on new results in the X-Ray domain from new telescopes such as Chandra and XMM Newton not mentioned in any other book. Furthermore, it considers also the Fermi Gamma Ray Space Telescope with its revolutionary advances of unprecedented sensitivity, field of view and all-sky monitoring. Those and other new developments as well as simulations of AGN merging events and formations, enabled through latest super-computing capabilities. The book gives an overview on the current knowledge of the Active Galacitc Nuclei phenomenon. The spectral energy d

  20. Direct Activation Of Methane

    KAUST Repository

    Basset, Jean-Marie

    2013-07-15

    Heteropolyacids (HPAs) can activate methane at ambient temperature (e.g., 20.degree. C.) and atmospheric pressure, and transform methane to acetic acid, in the absence of any noble metal such as Pd). The HPAs can be, for example, those with Keggin structure: H.sub.4SiW.sub.12O.sub.40, H.sub.3PW.sub.12O.sub.40, H.sub.4SiMo.sub.12O.sub.40, or H.sub.3PMo.sub.12O.sub.40, can be when supported on silica.

  1. Rationales for regulatory activity

    Energy Technology Data Exchange (ETDEWEB)

    Perhac, R.M. [Univ. of Tennessee, Knoxville, TN (United States)

    1997-02-01

    The author provides an outline which touches on the types of concerns about risk evaluation which are addressed in the process of establishing regulatory guides. Broadly he says regulatory activity serves three broad constituents: (1) Paternalism (private risk); (2) Promotion of social welfare (public risks); (3) Protection of individual rights (public risks). He then discusses some of the major issues encountered in reaching a decision on what is an acceptable level of risk within each of these areas, and how one establishes such a level.

  2. Microbiologically active nanocomposite media

    Science.gov (United States)

    Petranovskii, Vitalii; Panina, Lyudmila; Bogomolova, Eugenia; Belostotskaya, Galina

    2003-07-01

    The most recent approach to the development of novel antimicrobial and antifungal agents is based on the application of synthetic and natural zeolites, because zeolites are known to be the carrier and slow releaser of the heavy metals with olygodynamic properties. The microbiological activity of the ion-exchanged zeolites is attributed to the ionic state of the metal sreleased from the zeolites by ion re-exchange. In the present work we used low cost natural clinoptilolite (Cli) as a substrate for copper and silver in different states. The state of oxidation of the exchanged metal in zeolite with supported Cu and Ag species (in the form of cations, small clusters, sub-coloidal particles, large particles) in order to fit them to fulfill the following criteria: to demonstrate their high protective abilities against fungi and long-term stability. The study of structure of samples with XRD, UV-visible spectroscopy, FTIR, their stability with temperature and during storage was carried out for obtaining the correct correlation with microbiological activity.

  3. The Active Solid Earth

    Science.gov (United States)

    Ebinger, Cynthia

    2016-04-01

    Dynamic processes in Earth's crust, mantle and core shape Earth's surface and magnetic field over time scales of seconds to millennia, and even longer time scales as recorded in the ca. 4 Ga rock record. Our focus is the earthquake-volcano deformation cycles that occur over human time scales, and their comparison with time-averaged deformation studies, with emphasis on mantle plume provinces where magma and volatile release and vertical tectonics are readily detectable. Active deformation processes at continental and oceanic rift and back arc zones provide critical constraints on mantle dynamics, the role of fluids (volatiles, magma, water), and plate rheology. For example, recent studies of the East African rift zone, which formed above one of Earth's largest mantle upwellings reveal that magma production and volatile release rates are comparable to those of magmatic arcs, the archetypal zones of continental crustal creation. Finite-length faults achieve some plate deformation, but magma intrusion in the form of dikes accommodates extension in continental, back-arc, and oceanic rifts, and intrusion as sills causes permanent uplift that modulates the local time-space scales of earthquakes and volcanoes. Volatile release from magma intrusion may reduce fault friction and permeability, facilitating aseismic slip and creating magma pathways. We explore the implications of active deformation studies to models of the time-averaged structure of plume and extensional provinces in continental and oceanic plate settings.

  4. Active Optics in LAMOST

    Institute of Scientific and Technical Information of China (English)

    Ding-Qiang Su; Xiang-Qun Cui

    2004-01-01

    Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)is one of the major national projects under construction in China. Active optics is one of the most important technologies for new large telescopes. It is used for correcting telescope errors generated by gravitational and thermal changes. Here,however, we use this technology to realize the configuration of LAMOST, -a task that cannot be done in the traditional way. A comprehensive and intensive research on the active optics used in LAMOST is also reported, including an open-loop control method and an auxiliary closed-loop control method. Another important development is in our pre-calibration method of open-loop control, which is with some new features: simultaneous calculation of the forces and displacements of force actuators and displacement actuators; the profile of mirror can be arbitrary;the mirror surface shape is not expressed by a fitting polynomial, but is derived from the mirror surface shape formula which is highly accurate; a proof is given that the solution of the pre-calibration method is the same as the least squares solution.

  5. Active Astronomy Roadshow Haiti

    Science.gov (United States)

    Laycock, Silas; Oram, Kathleen; Alabre, Dayana; Douyon, Ralph; UMass Lowell Haiti Development Studies Center

    2016-01-01

    College-age Haitian students working with advisors and volunteers from UMass Lowell in 2015 developed and tested an activity-based K-8 curriculum in astronomy, space, and earth science. Our partner school is located in Les Cayes, Haiti a city where only 65% of children attend school, and only half of those will complete 6th grade. Astronomy provides an accessible and non-intimidating entry into science, and activity-based learning contrasts with the predominant traditional teaching techniques in use in Haiti, to reach and inspire a different cohort of learners. Teachers are predominantly women in Haiti, so part of the effort involves connecting them with scientists, engineers and teacher peers in the US. As a developing nation, it is vital for Haitian (as for all) children to grow up viewing women as leaders in science. Meanwhile in the US, few are aware of the reality of getting an education in a 3rd world nation (i.e. most of the world), so we also joined with teachers in Massachusetts to give US school children a peek at what daily life is like for their peers living in our vibrant but impoverished neighbor. Our Haitian partners are committed to helping their sister-schools with curriculum and educator workshops, so that the overall quality of education can rise, and not be limited to the very few schools with access to resources. We will describe the activites, motivation, and and the lessons learned from our first year of the project.

  6. Leadership Development Activities

    Directory of Open Access Journals (Sweden)

    Malikeh Beheshtifar

    2012-07-01

    Full Text Available Nowadays, human resource development is considered as a developed concept in HR field. It is a process for helping personnel to conduct their duties better. Most organizations tend to leadership development as a separable subject and as areas of responsibility within organization. Whereas the leadership development plans have been unsuccessful. This article aim to draw attention to the fact that leadership development is crucial in organizations. A literature review was conducted by searching journal databases, textbooks, and relevant reports. A categorization of the evidence allowed informed discussions on the key themes surrounding leadership development activities. Leadership development is caused to employees' promotion and progress via nurture of new talents, stimulus in employees by persuade to do individual development, save time and cost, and increase customers' satisfaction by relations improvement. Accordingly, the development systems can cover a wide scope in organization. They are effective to career management, training and development, performance management, strategic human resource planning, recruitment and selection, and succession planning activities. Despite the need for further scientific and validated studies, organizations should be urged to devote sufficient resources and attention towards leadership development for promoting long-term survival and prosperity.

  7. Involvement in Physical Activity

    Directory of Open Access Journals (Sweden)

    James Gavin

    2013-04-01

    Full Text Available A total of 1,096 adolescents participated in 123 focus groups regarding the perceived outcomes of their involvement in sports and physical activity (PA. The groups, segmented by grade level, sex, and school types, were conducted in both public and private high schools in Montreal, Quebec. We sought to understand, through the participants’ own words, their perception of the outcome matrix of involvement in sports and PA. Focus group questions emphasized changes that adolescents associated with such engagement. In particular, participants were asked how sports and PA might influence behaviors, emotional states, personal characteristics, and other outcomes. Twelve themes were identified in the responses: Positive Health and Physical Changes (18.5%, Activity-Related Positive Emotions (15.6%, and Personal Learning (11.3% were most prevalent in the discussions. A cluster of deeper personal changes thematically described as Self-Identity, Autonomy, and Positive Character Development accounted for another 16.5% of the responses. Relatively few commentaries emphasized negative effects (7.1%. Converting the proportions of qualitative data into a quantitative index allowed us to analyze potential differences in emphasis according to sex, age, and school type. Though a few significant findings emerged, the larger pattern was of a uniform perceptual map across the variables for this adolescent sample. Implications drawn from this investigation highlight the need to clearly articulate concrete pathways to positive nonphysical changes (e.g., mood states, autonomy, positive character development from engagements in sports and PA.

  8. CBP Active Dumping and Active Countervailing (AD/CVD) Cases

    Data.gov (United States)

    Department of Homeland Security — The datasets provide information from CBP's reference files on active anti-dumping and active countervailing cases. This data includes associated case numbers (if...

  9. Sedentary activity associated with metabolic syndrome independent of physical activity

    DEFF Research Database (Denmark)

    Bankoski, Andrea; Harris, Tamara B; McClain, James J

    2011-01-01

    This study examined the association between objectively measured sedentary activity and metabolic syndrome among older adults.......This study examined the association between objectively measured sedentary activity and metabolic syndrome among older adults....

  10. Characterization and distribution of esterase activity in activated sludge

    NARCIS (Netherlands)

    Boczar, BA; Forney, LJ; Begley, WM; Larson, RJ; Federle, TW

    2001-01-01

    The location and activity of esterase enzymes in activated Sludge from three Municipal wastewater treatment plants were characterized using model Substrate, and denaturing and nondenaturing polyacrylamide gel electrophoresis (PAGE) Of particulate, freeze thaw (primarily periplasmic enzymes and those

  11. The active video games' narrative impact on children's physical activities

    Science.gov (United States)

    Active video games (AVGs) capable of inducing physical activity offer an innovative approach to combating childhood obesity. Unfortunately, children's AVG game play decreases quickly, underscoring the need to identify novel methods for player engagement. Narratives have been demonstrated to influenc...

  12. INFLUENCE OF SELECTED PHARMACEUTICALS ON ACTIVATED SLUDGE DEHYDROGENASE ACTIVITY

    Directory of Open Access Journals (Sweden)

    Agnieszka Tomska

    2016-06-01

    The aim of this work was to evaluate the effect of selected antibiotics - sulfanilamide and erythromycin on activated sludge dehydrogenase activity with use of trifenyltetrazolinum chloride (TTC test. Dehydrogenases activity is an indicator of biochemical activity of microorganisms present in activated sludge or the ability to degrade organic compounds in waste water. TTC test is particularly useful for the regularity of the course of treatment, in which the presence of inhibitors of biochemical reactions and toxic compounds are present. It was observed that the dehydrogenase activity decreases with the increase of a antibiotics concentration. The lowest value of the dehydrogenase activity equal to 32.4 μmol TF / gMLSS obtained at sulfanilamide concentration 150mg / l. For this sample, an inhibition of dehydrogenase activity was 31%.

  13. How Active Are Older Americans?

    Directory of Open Access Journals (Sweden)

    Judy Kruger, PhD

    2007-07-01

    Full Text Available IntroductionRegular physical activity can reduce age-related functional decline, as well people’s risk for chronic diseases such as coronary heart disease, hypertension, colon cancer, and diabetes. The objective of this study was to estimate the level of participation in aerobic, muscle-strengthening, and flexibility activities among Americans aged 50 years or older.MethodsUsing population-based data from the 2001 National Health Interview Survey, we classified qualified respondents (N = 11,969 according to whether they met the activity criteria used in Healthy People 2010 goals for leisure-time participation in regular aerobic physical activity, vigorous-intensity aerobic activity, strength-training activity, and flexibility activity. We also classified respondents according to their level of aerobic activity (i.e., inactive, insufficiently active, and regularly active.ResultsWe estimated that 46.4% of older Americans engaged in no leisure-time aerobic activity; that 26.1% were regularly active (participated in light- to moderate-intensity aerobic activities at least 5 days per week for at least 30 minutes or vigorous-intensity activities at least 3 days per week for at least 20 minutes; that 16.2% participated in vigorous-intensity aerobic activities at least 3 days per week for at least 20 minutes; that 13.7% participated in strength-training activities at least 2 days per week; and that 24.5% participated in flexibility activities at least 1 day per week. Among the 26.1% of older Americans who were regularly active, 30.5% engaged in strengthen-training activities at least 2 days per week. Overall, only 8.2% of older Americans met the criteria for both aerobic and strength-training activity.ConclusionAs of 2001, the percentage of older Americans who met recommended activity levels of physical activity were well below the goals for U.S. adults in Healthy People 2010. Further efforts are needed to encourage older Americans to engage in

  14. Active Magnetic Regenerative Liquefier

    Energy Technology Data Exchange (ETDEWEB)

    Barclay, John A. [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Oseen-Send, Kathryn [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Ferguson, Luke [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Pouresfandiary, Jamshid [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Cousins, Anand [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Ralph, Heather [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Hampto, Tom [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States)

    2016-01-12

    This final report for the DOE Project entitled Active Magnetic Regenerative Liquefier (AMRL) funded under Grant DE-FG36-08GO18064 to Heracles Energy Corporation d.b.a. Prometheus Energy (Heracles/Prometheus) describes an active magnetic regenerative refrigerator (AMRR) prototype designed and built during the period from July 2008 through May 2011. The primary goal of this project was to make significant technical advances toward highly efficient liquefaction of hydrogen. Conventional hydrogen liquefiers at any scale have a maximum FOM of ~0.35 due primarily to the intrinsic difficulty of rapid, efficient compression of either hydrogen or helium working gases. Numerical simulation modeling of high performance AMRL designs indicates certain designs have promise to increase thermodynamic efficiency from a FOM of ~0.35 toward ~0.5 to ~0.6. The technical approach was the use of solid magnetic working refrigerants cycled in and out of high magnetic fields to build an efficient active regenerative magnetic refrigeration module providing cooling power for AMRL. A single-stage reciprocating AMRR with a design temperature span from ~290 K to ~120 K was built and tested with dual magnetic regenerators moving in and out of the conductively-cooled superconducting magnet subsystem. The heat transfer fluid (helium) was coupled to the process stream (refrigeration/liquefaction load) via high performance heat exchangers. In order to maximize AMRR efficiency a helium bypass loop with adjustable flow was incorporated in the design because the thermal mass of magnetic refrigerants is higher in low magnetic field than in high magnetic field. Heracles/Prometheus designed experiments to measure AMRR performance under a variety of different operational parameters such as cycle frequency, magnetic field strength, heat transfer fluid flow rate, amount of bypass flow of the heat transfer fluid while measuring work input, temperature span, cooling capability as a function of cold temperature

  15. Examining Activism in Practice: A Qualitative Study of Archival Activism

    Science.gov (United States)

    Novak, Joy Rainbow

    2013-01-01

    While archival literature has increasingly discussed activism in the context of archives, there has been little examination of the extent to which archivists in the field have accepted or incorporated archival activism into practice. Scholarship that has explored the practical application of archival activism has predominately focused on case…

  16. Youth Physical Activity Resource Use and Activity Measured by Accelerometry

    Science.gov (United States)

    Maslow, Andra L.; Colabianchi, Natalie

    2011-01-01

    Objectives: To examine whether use of physical activity resources (e.g., parks) was associated with daily physical activity measured by accelerometry. Methods: One hundred eleven adolescents completed a travel diary with concurrent accelerometry. The main exposure was self-reported use of a physical activity resource (none /1 resources). The main…

  17. Project origami activities for exploring mathematics

    CERN Document Server

    Hull, Thomas

    2012-01-01

    IntroductionActivity 1 Folding Equilateral Triangles in a Square Activity 2 Origami Trigonometry Activity 3 Dividing a Length into Equal Nths: Fujimoto Approximation Activity 4 Dividing a Length into Equal Nths Exactly Activity 5 Origami Helix Activity 6 Folding a Parabola Activity 7 Can Origami Trisect an Angle?Activity 8 Solving Cubic Equations Activity 9 Lill's Method Activity 10 Folding Strips into Knots Activity 11 Haga's ""Origamics"" Activity 12 Modular Star Ring Activity 13 Folding a Butterfly Bomb Activity 14 Molly's Hexahedron Activity 15 Business Card Modulars Activity 16 Five Inter

  18. Active Ageing: An Analysis

    Directory of Open Access Journals (Sweden)

    Alina-Cristina Nuta

    2011-10-01

    Full Text Available The problem of ageing is a highly topical for Romania and for European Union. In this framework, to create and implement some strategies for active ageing is an important objective. The international and regional forums set (supported by official statistics that the number of older people growing rapidly. Romania needs some programmes (with labour, social, economic, health care aspects to deal with the demographic changes, programs that will reform the existing working life structures and legislation. Despite the actual pension reform, which tries to close the opportunity of early retirement (by penalizing the total pension flows, or increasing the retirement age, etc., the labour system does not sets some important targets for this area.

  19. DPAL activities in Japan

    Science.gov (United States)

    Endo, Masamori; Wani, Fumio

    2015-02-01

    Activities on diode pumped alkali laser (DPAL) in Japan is reviewed. We have started alkali laser works in 2011, and currently, we are the only players in Japan. Our interests are application oriented, and it is not only defense but also industrial. DPAL is a good candidate as a source of remote laser machining, thanks to its scalability and extremely good beam quality. We are studying on scientific and engineering problems of Cs DPAL with a small-scale apparatus. A commercial diode laser with volume Bragg grating outcoupler is used to pump the gain cell longitudinally. A 6.5 W continuous-wave output with optical to optical efficiency of 56% (based on the absorbed power) has been achieved. Numerical simulation codes are developed to understand the physics of DPAL and to help future developments.

  20. SPORTS ACTIVITIES SPONSORSHIP

    Directory of Open Access Journals (Sweden)

    DURBĂCEA - BOLOVAN MARIAN

    2016-12-01

    Full Text Available Sports and economy have discovered each other, hoping to serve common interests. In view of transferring in a more efficient way the information about their products or services to consumers, the business operator finances sports activities for advertising purposes. A company involved in sports sponsorship can instantly transmit the message about its products to millions of potential buyers, thus increasing the market share and hence the profit that it generates. By sponsoring sport it is meant any agreement / convention, under which one party the sponsor makes available to the beneficiary the material resources, financial and / or other benefits in exchange for its association with a sport or sportsman and especially the promise to use this association with sport or sportsman for the purpose of advertising, especially TV advertising. The growing use of athletes as spokespersons for a product is largely due to the ability of athletes to attract public attention and the credibility they enjoy

  1. The sound of activism.

    Science.gov (United States)

    Sandstrom, B; Vetter, C

    2001-01-01

    ABSTRACT A longtime advocate for female empowerment and equality, Boden Sandstrom has worked for political change in many arenas. In the 1960s, she began a career as a librarian, but soon made activism her full-time job, working for feminist, leftist and socialist causes. In the 1970s, she found a way to turn her lifelong passion for music into a career as a sound engineer. Once established in that profession, she began donating her services to political events, marches, demonstrations, and rallies. After thirteen years of running her own company, called Woman Sound,Inc. (later City Sound Productions,Inc.), she turned to the study of ethnomusicology. She is now Program Manager and Lecturer for the Ethnomusicology Program at the University of Maryland, where she is also working on her doctorate in that subject. She continues to freelance as a sound engineer and serve as a technical producer for major events.

  2. Actively stressed marginal networks

    CERN Document Server

    Sheinman, M; MacKintosh, F C

    2012-01-01

    We study the effects of motor-generated stresses in disordered three dimensional fiber networks using a combination of a mean-field, effective medium theory, scaling analysis and a computational model. We find that motor activity controls the elasticity in an anomalous fashion close to the point of marginal stability by coupling to critical network fluctuations. We also show that motor stresses can stabilize initially floppy networks, extending the range of critical behavior to a broad regime of network connectivities below the marginal point. Away from this regime, or at high stress, motors give rise to a linear increase in stiffness with stress. Finally, we demonstrate that our results are captured by a simple, constitutive scaling relation highlighting the important role of non-affine strain fluctuations as a susceptibility to motor stress.

  3. Actively stressed marginal networks.

    Science.gov (United States)

    Sheinman, M; Broedersz, C P; MacKintosh, F C

    2012-12-07

    We study the effects of motor-generated stresses in disordered three-dimensional fiber networks using a combination of a mean-field theory, scaling analysis, and a computational model. We find that motor activity controls the elasticity in an anomalous fashion close to the point of marginal stability by coupling to critical network fluctuations. We also show that motor stresses can stabilize initially floppy networks, extending the range of critical behavior to a broad regime of network connectivities below the marginal point. Away from this regime, or at high stress, motors give rise to a linear increase in stiffness with stress. Finally, we demonstrate that our results are captured by a simple, constitutive scaling relation highlighting the important role of nonaffine strain fluctuations as a susceptibility to motor stress.

  4. Active Flow Control

    Science.gov (United States)

    FFOWCS WILLIAMS, J. E.

    2001-01-01

    This paper considers the two-dimensional problem of a plane vortex sheet disturbed by an impulsive line source. A previous incorrect treatment of this problem is examined in detail. Instabilities of the vortex sheet are triggered by the source and grow exponentially in space and time. The Green function is constructed for the problem and it is shown that a point source properly positioned and delayed will induce a field that cancels the unstable growing modes. The resulting displacement of the vortex sheet is expressed in simple terms. The instabilities are checked by the anti-source which combines with the field of the primary source into a vortex sheet response which decays with time at large time. This paper is a contribution to the study of active control of shear layer instabilities, the main contribution being to clear up a previous paper with peculiar results that are, in fact, wrong.

  5. Respiratory active mitochondrial supercomplexes.

    Science.gov (United States)

    Acín-Pérez, Rebeca; Fernández-Silva, Patricio; Peleato, Maria Luisa; Pérez-Martos, Acisclo; Enriquez, Jose Antonio

    2008-11-21

    The structural organization of the mitochondrial respiratory complexes as four big independently moving entities connected by the mobile carriers CoQ and cytochrome c has been challenged recently. Blue native gel electrophoresis reveals the presence of high-molecular-weight bands containing several respiratory complexes and suggesting an in vivo assembly status of these structures (respirasomes). However, no functional evidence of the activity of supercomplexes as true respirasomes has been provided yet. We have observed that (1) supercomplexes are not formed when one of their component complexes is absent; (2) there is a temporal gap between the formation of the individual complexes and that of the supercomplexes; (3) some putative respirasomes contain CoQ and cytochrome c; (4) isolated respirasomes can transfer electrons from NADH to O(2), that is, they respire. Therefore, we have demonstrated the existence of a functional respirasome and propose a structural organization model that accommodates these findings.

  6. Plasminogen activation and cancer

    DEFF Research Database (Denmark)

    Danø, Keld; Behrendt, N.; Hoyer-Hansen, G.

    2005-01-01

    Breakdown of the extracellular matrix is crucial for cancer invasion and metastasis. It is accomplished by the concerted action of several proteases, including the serine protease plasmin and a number of matrix metalloproteases.The activity of each of these proteases is regulated by an array......, the regulation of extracellular proteolysis in cancer involves a complex interplay between cancer cells and non-malignant stromal cells in the expression of the molecular components involved. For some types of cancer, this cellular interplay mimics that observed in the tissue of ori- gin during non......-neoplastic tissue remodelling processes.We propose that cancer invasion can be considered as uncontrolled tissue remodelling. Inhibition of extracellular proteases is an attractive approach to cancer therapy. Because proteases have many different functions in the normal organism, efficient inhibition will have...

  7. Physical activity among adolescents

    DEFF Research Database (Denmark)

    Henriksen, P W; Ingholt, L; Rasmussen, M

    2016-01-01

    The objectives of this study were (a) to examine the association between various kinds of parental social support and adolescents' physical activity (PA) and (b) to examine whether various kinds of social support from mothers and fathers were differently associated with boys' and girls' PA. Data...... during leisure time. We used logistic regression analyses to estimate the associations for girls and boys separately, adjusted by age group, parents' occupational social class, family structure, and migration status. There were significant and graded associations between adolescents' PA and all four...... dimensions of parental support for PA. The association patterns were similar for mothers' and fathers' social support and similar for girls and boys. Social processes in the family are important for adolescents' participation in PA. It is important to continue to explore these social processes in order...

  8. Existing chemicals: international activities.

    Science.gov (United States)

    Purchase, J F

    1989-01-01

    The standards of care used in the protection of the health and safety of people exposed to chemicals has increased dramatically in the last decade. Standards imposed by regulation and those adopted by industry have required a greater level of knowledge about the hazards of chemicals. In the E.E.C., the 6th amendment of the dangerous substances directive imposed the requirement that al new chemicals should be tested according to prescribed programme before introduction on to the market. The development of a European inventory of existing chemicals was an integral part of the 6th amendment. It has now become clear that increased standards of care referred to above must be applied to the chemicals on the inventory list. There is, however, a considerable amount of activity already under way in various international agencies. The OECD Chemicals Programme has been involved in considering the problem of existing chemicals for some time, and is producing a priority list and action programme. The International Programme on Chemical Safety produces international chemical safety cards, health and safety guides and environmental health criteria documents. The international register of potentially toxic compounds (part of UNEP) has prepared chemical data profiles on 990 compounds. The International Agency for Research on Cancer prepared monographs on the carcinogenic risk of chemicals to man. So far 42 volumes have been prepared covering about 900 substances. IARC and IPCS also prepare periodic reports on ongoing research on carcinogenicity or toxicity (respectively) of chemicals. The chemical industry through ECETOC (the European Chemical Industry Ecology and Toxicology Centre) has mounted a major initiative on existing chemicals. Comprehensive reviews of the toxicity of selected chemicals are published (Joint Assessment of Commodity Chemicals). In its technical report no. 30 ECETOC lists reviews and evaluations by major national and international organisations, which provides

  9. Water-soluble IrIII N-heterocyclic carbene based catalysts for the reduction of CO2 to formate by transfer hydrogenation and the deuteration of aryl amines in water.

    Science.gov (United States)

    Azua, Arturo; Sanz, Sergio; Peris, Eduardo

    2011-03-28

    Two new water-soluble [IrI(2)(AcO)(bis-NHC)] complexes (NHC=N-heterocyclic carbene) incorporating a sulfonate functionality have been synthesized. The two complexes have been tested in the reduction of CO(2) with H(2) and iPrOH, and their activity has been compared with similar species without the sulfonate moiety. In both reactions, the complex with the two abnormally bound NHCs shows the best catalytic efficiencies, due to the higher σ-electron-donor character of the ligand. Remarkably, the activities obtained for the reduction of CO(2) under the transfer hydrogenation conditions are the best reported to date in terms of TON value (max. TON=2700). The two new complexes have also shown very good activity in the selective deuteration of arylamines, a process that is known to proceed through a chelate assisted N-directed process.

  10. Diabetes Diet, Eating, & Physical Activity

    Science.gov (United States)

    ... Disease, & Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetes Diet, Eating, & Physical Activity Nutrition and physical activity ... What foods can I eat if I have diabetes? You may worry that having diabetes means going ...

  11. Consolidated Human Activities Database (CHAD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Consolidated Human Activity Database (CHAD) contains data obtained from human activity studies that were collected at city, state, and national levels. CHAD is...

  12. Motivating Kids to Be Active

    Science.gov (United States)

    ... set healthy patterns that will last into adulthood. Benefits of Being Active When kids are active, their ... school sports to after-school interests, such as yoga or skateboarding. It's important to remember that physical ...

  13. Physical Activity and Your Heart

    Science.gov (United States)

    ... more energy than resting. Walking, running, dancing, swimming, yoga, and gardening are a few examples of physical activity. According to the Department of Health and Human Services' 2008 Physical Activity Guidelines for ...

  14. Physical activity extends life expectancy

    Science.gov (United States)

    Leisure-time physical activity is associated with longer life expectancy, even at relatively low levels of activity and regardless of body weight, according to a study by a team of researchers led by the NCI.

  15. Advanced Active Acoustics Lab (AAAL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Active Acoustics Lab (AAAL) is a state-of-the-art Undersea Warfare (USW) acoustic data analysis facility capable of both active and passive underwater...

  16. Physical active rest in education of active personality of students

    Directory of Open Access Journals (Sweden)

    Zaycev V.P.

    2010-10-01

    Full Text Available Meaningfulness of physical recreation is rotined in education of active personality of students. Research material is literary sources on this issue. Factors which influence on an educate function of personality of students are considered. Application of physical recreation is grounded for education of active personality of students. It is marked that physical recreation in pedagogical process decides educate, educational, health and social tasks. It positively influences on education of active personality of students. It is rotined that in education of active personality of students an important role is played by their research activity.

  17. Automated activity-aware prompting for activity initiation.

    Science.gov (United States)

    Holder, Lawrence B; Cook, Diane J

    2013-01-01

    Performing daily activities without assistance is important to maintaining an independent functional lifestyle. As a result, automated activity prompting systems can potentially extend the period of time that adults can age in place. In this paper we introduce AP, an algorithm to automate activity prompting based on smart home technology. AP learns prompt rules based on the time when activities are typically performed as well as the relationship between activities that normally occur in a sequence. We evaluate the AP algorithm based on smart home datasets and demonstrate its ability to operate within a physical smart environment.

  18. Writing clear animal activity proposals.

    Science.gov (United States)

    Pinson, David M

    2011-06-01

    Although IACUC-related topics are frequently discussed in the literature, there is little published information about how to write animal activity proposals. In this article, the author discusses key considerations in the writing and review of animal activity proposals. The author then describes a framework for developing and writing clear animal activity proposals that highlight animal welfare concerns. Though these recommendations are aimed at individuals writing and reviewing research proposals, the framework can be modified for other types of animal activity proposals.

  19. Danish Labour Market Activation Policies

    DEFF Research Database (Denmark)

    Kvist, Jon; Pedersen, LIsbeth

    2007-01-01

    transformation over the past fifteen years. From the initial curbing of unemployment among the insured unemployed through standard activation offers, the aim today is also to increase labour supply among non-economic active groups using individually tailored programmes. Danish activation policies this embrace...

  20. Assessing and Increasing Physical Activity

    Science.gov (United States)

    Van Camp, Carole M.; Hayes, Lynda B.

    2012-01-01

    Increasing physical activity is a crucial component of any comprehensive approach to combat the growing obesity epidemic. This review summarizes recent behavioral research on the measurement of physical activity and interventions aimed at increasing physical activity and provides directions for future research.

  1. Water-Related Teaching Activities.

    Science.gov (United States)

    Coon, Herbert L.; Price, Charles L.

    This publication is designed to provide interested teachers with teaching activities for all grade levels and subject areas that can be used to help students learn about water resources. For each activity, the purpose, level, subject, and concept are given. Activities are organized by grade level. Most of these water related learning activities…

  2. Optically active quantum dots

    Science.gov (United States)

    Gerard, Valerie; Govan, Joseph; Loudon, Alexander; Baranov, Alexander V.; Fedorov, Anatoly V.; Gun'ko, Yurii K.

    2015-10-01

    The main goal of our research is to develop new types of technologically important optically active quantum dot (QD) based materials, study their properties and explore their biological applications. For the first time chiral II-VI QDs have been prepared by us using microwave induced heating with the racemic (Rac), D- and L-enantiomeric forms of penicillamine as stabilisers. Circular dichroism (CD) studies of these QDs have shown that D- and L-penicillamine stabilised particles produced mirror image CD spectra, while the particles prepared with a Rac mixture showed only a weak signal. It was also demonstrated that these QDs show very broad emission bands between 400 and 700 nm due to defects or trap states on the surfaces of the nanocrystals. These QDs have demonstrated highly specific chiral recognition of various biological species including aminoacids. The utilisation of chiral stabilisers also allowed the preparation of new water soluble white emitting CdS nano-tetrapods, which demonstrated circular dichroism in the band-edge region of the spectrum. Biological testing of chiral CdS nanotetrapods displayed a chiral bias for an uptake of the D- penicillamine stabilised nano-tetrapods by cancer cells. It is expected that this research will open new horizons in the chemistry of chiral nanomaterials and their application in nanobiotechnology, medicine and optical chemo- and bio-sensing.

  3. [Active management of labor].

    Science.gov (United States)

    Ruiz Ortiz, E; Villalobos Román, M; Flores Murrieta, G; Sotomayor Alvarado, L

    1991-01-01

    Eighty three primigravidae patients at the end of latency labor, erased cervix, 3 cm dilation, vertex presentation and adequate pelvis, were studied. Two groups were formed: 53 patients in the study group, who received active management of labor, and 30 patients in the control group, treated in the traditional way. In all the patients a graphic recording of labor, was carried out; it included all the events, and as labor advanced, a signoidal curve of cervical dilatation, was registered, as well as the hyperbolic one for presentation descent. The study group received the method in a systematized manner, as follows: 1. Peridular block. 2. Amniotomy. 3. IV oxytocin one hour after amniotomy. 4. FCR monitoring. 5. Detection of dystocia origin. Materno-fetal morbidity was registered in both groups, as well as cesarean section rate, instrumental delivery and its indications, labor duration, and time of stay in labor room. Diminution of above intems and opportune detection of dystocia, were determined. It was concluded that a constructive action plan, starting at hospital admission in most healthy women, allows a normal delivery of brief duration.

  4. Surface Active Components: Review

    Directory of Open Access Journals (Sweden)

    Z. Shafiei

    2014-03-01

    Full Text Available Biosurfactant or surface active components are produced by many different microorganisms. Biosurfactants are amphiphilic molecules with both hydrophilic and hydrophobic (generally hydrocarbon moieties that partition preferentially a within the interface between fluid phases with some other degrees of polarity and hydrogen bonding including oil/water or air/water interfaces. These properties render surfactants able to reducing surface and interfacial tension and forming microemulsion where hydrocarbons can solubilize in water or where water can solubilize in hydrocarbons, the majority of surfactants have gained importance in the fields of enhanced oil recovery, environmental bioremediation, food processing and pharmaceuticals. However, large-scale production of these molecules has not been realized as a result of low yields in production processes and high recovery and purification costs. This review article represents a classification of biosurfactant in addition to their microbial origin and effect of some nutrition and environmental factor for high production of biosurfactant. The nitrogen, carbon sources and environmental factors can make a difference key to the regulating biosurfactants synthesis Fascination with microbial surfactants have been steadily increasing recently because of advantages over the chemical surfactants for example environmentally friendly nature, lower toxicity, higher biodegradability, higher selectivity and specific gravity at extreme temperature, pH and salinity. For this reason the demand of biosurfactant are increasing day by day.

  5. Elusive Active Galactic Nuclei

    CERN Document Server

    Maiolino, R; Gilli, R; Nagar, N M; Bianchi, S; Böker, T; Colbert, E; Krabbe, A; Marconi, A; Matt, G; Salvati, M

    2003-01-01

    A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new Chandra observations with archival X-ray data in order to obtain a first estimate of the fraction of elusive AGN in local galaxies and to constrain their nature. Our results suggest that elusive AGN have a local density comparable to or even higher than optically classified Seyfert nuclei. Most elusive AGN are heavily absorbed in the X-rays, with gas column densities exceeding 10^24 cm^-2, suggesting that their peculiar nature is associated with obscuration. It is likely that in elusive AGN, the nuclear UV source is completely embedded and the ionizing photons cannot escape, which prevents the formation of a classical Narrow Line Region. Elusive AGN may contribute significantly to the 30 keV bump of the X-ray background.

  6. ADASY (Active Daylighting System)

    Science.gov (United States)

    Vázquez-Moliní, Daniel; González-Montes, Mario; Fernández-Balbuena, Antonio Á.; Bernabéu, Eusebio; García-Botella, Ángel; García-Rodríguez, Lucas; Pohl, Wilfried

    2009-08-01

    The main objective of ADASY (Active Daylighting System) work is to design a façade static daylighting system oriented to office applications, mainly. The goal of the project is to save energy by guiding daylight into a building for lighting purpose. With this approach we can reduce the electrical load for artificial lighting, completing it with sustainable energy. The collector of the system is integrated on a vertical façade and its distribution guide is always horizontal inside of the false ceiling. ADASY is designed with a specific patent pending caption system, a modular light-guide and light extractor luminaire system. Special care has been put on the final cost of the system and its building integration purpose. The current ADASY configuration is able to illuminate 40 m2 area with a 300lx-400lx level in the mid time work hours; furthermore it has a good enough spatial uniformity distribution and a controlled glare. The data presented in this study are the result of simulation models and have been confirmed by a physical scaled prototype. ADASY's main advantages over regular illumination systems are: -Low maintenance; it has not mobile pieces and therefore it lasts for a long time and require little attention once installed. - No energy consumption; solar light continue working even if there has been a power outage. - High quality of light: the colour rendering of light is very high - Psychological benefits: People working with daylight get less stress and more comfort, increasing productivity. - Health benefits

  7. Barriers for recess physical activity

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper

    2014-01-01

    BACKGROUND: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender...... differences in children's perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. METHODS: Data were collected through 17 focus groups (at 17 different schools...... this study, we recommend promoting recess physical activity through a combination of actions, addressing barriers within the natural, social, physical and organizational environment....

  8. Perspectives in active liquid crystals.

    Science.gov (United States)

    Majumdar, Apala; Cristina, Marchetti M; Virga, Epifanio G

    2014-11-28

    Active soft matter is a young, growing field, with potential applications to a wide variety of systems. This Theme Issue explores this emerging new field by highlighting active liquid crystals. The collected contributions bridge theory to experiment, mathematical theories of passive and active nematics, spontaneous flows to defect dynamics, microscopic to continuum levels of description, spontaneous activity to biological activation. While the perspectives offered here only span a small part of this rapidly evolving field, we trust that they might provide the interested reader with a taste for this new class of non-equilibrium systems and their rich behaviour.

  9. In vivo imaging of protease activity by Probody therapeutic activation.

    Science.gov (United States)

    Wong, Kenneth R; Menendez, Elizabeth; Craik, Charles S; Kavanaugh, W Michael; Vasiljeva, Olga

    2016-03-01

    Probody™ therapeutics are recombinant, proteolytically-activated antibody prodrugs, engineered to remain inert until activated locally by tumor-associated proteases. Probody therapeutics exploit the fundamental dysregulation of extracellular protease activity that exists in tumors relative to healthy tissue. Leveraging the ability of a Probody therapeutic to bind its target at the site of disease after proteolytic cleavage, we developed a novel method for profiling protease activity in living animals. Using NIR optical imaging, we demonstrated that a non-labeled anti-EGFR Probody therapeutic can become activated and compete for binding to tumor cells in vivo with a labeled anti-EGFR monoclonal antibody. Furthermore, by inhibiting matriptase activity in vivo with a blocking-matriptase antibody, we show that the ability of the Probody therapeutic to bind EGFR in vivo was dependent on protease activity. These results demonstrate that in vivo imaging of Probody therapeutic activation can be used for screening and characterization of protease activity in living animals, and provide a method that avoids some of the limitations of prior methods. This approach can improve our understanding of the activity of proteases in disease models and help to develop efficient strategies for cancer diagnosis and treatment.

  10. Global optogenetic activation of inhibitory interneurons during epileptiform activity.

    Science.gov (United States)

    Ledri, Marco; Madsen, Marita Grønning; Nikitidou, Litsa; Kirik, Deniz; Kokaia, Merab

    2014-02-26

    Optogenetic techniques provide powerful tools for bidirectional control of neuronal activity and investigating alterations occurring in excitability disorders, such as epilepsy. In particular, the possibility to specifically activate by light-determined interneuron populations expressing channelrhodopsin-2 provides an unprecedented opportunity of exploring their contribution to physiological and pathological network activity. There are several subclasses of interneurons in cortical areas with different functional connectivity to the principal neurons (e.g., targeting their perisomatic or dendritic compartments). Therefore, one could optogenetically activate specific or a mixed population of interneurons and dissect their selective or concerted inhibitory action on principal cells. We chose to explore a conceptually novel strategy involving simultaneous activation of mixed populations of interneurons by optogenetics and study their impact on ongoing epileptiform activity in mouse acute hippocampal slices. Here we demonstrate that such approach results in a brief initial action potential discharge in CA3 pyramidal neurons, followed by prolonged suppression of ongoing epileptiform activity during light exposure. Such sequence of events was caused by massive light-induced release of GABA from ChR2-expressing interneurons. The inhibition of epileptiform activity was less pronounced if only parvalbumin- or somatostatin-expressing interneurons were activated by light. Our data suggest that global optogenetic activation of mixed interneuron populations is a more effective approach for development of novel therapeutic strategies for epilepsy, but the initial action potential generation in principal neurons needs to be taken in consideration.

  11. Evaluating Active U: an internet-mediated physical activity program

    Directory of Open Access Journals (Sweden)

    Goodrich David E

    2009-09-01

    Full Text Available Abstract Background Engaging in regular physical activity can be challenging, particularly during the winter months. To promote physical activity at the University of Michigan during the winter months, an eight-week Internet-mediated program (Active U was developed providing participants with an online physical activity log, goal setting, motivational emails, and optional team participation and competition. Methods This study is a program evaluation of Active U. Approximately 47,000 faculty, staff, and graduate students were invited to participate in the online Active U intervention in the winter of 2007. Participants were assigned a physical activity goal and were asked to record each physical activity episode into the activity log for eight weeks. Statistics for program reach, effectiveness, adoption, and implementation were calculated using the Re-Aim framework. Multilevel regression analyses were used to assess the decline in rates of data entry and goal attainment during the program, to assess the likelihood of joining a team by demographic characteristics, to test the association between various predictors and the number of weeks an individual met his or her goal, and to analyze server load. Results Overall, 7,483 individuals registered with the Active U website (≈16% of eligible, and 79% participated in the program by logging valid data at least once. Staff members, older participants, and those with a BMI P Conclusion Internet-mediated physical activity interventions that focus on physical activity logging and goal setting while incorporating team competition may help a significant percentage of the target population maintain their physical activity during the winter months.

  12. Resources Management in Active Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In an active network, users can insert customized active codes into active nodes to execute. Thus it needs more resources than those required by conventional networks, and these resources must be effectively monitored and managed. Management policies in existing OSs are too complicated to apply to simple active packets. In this paper, we present new resources management policies that are mainly adoped to manage CPU, storage and transmission bandwidth. Namely, we use SPF algorithm to schedule and process active packets, and import an interval queue method to allocate transmission bandwidth, and use feedback mechanism to control congestion. At the same time, we design some experiments on prototype systems with and without resources management policies respectively. The experiments results show that management policies presented by us can effectively manage resources in active nodes and can improve the performance of active networks.

  13. Activity cliffs and activity cliff generators based on chemotype-related activity landscapes.

    Science.gov (United States)

    Pérez-Villanueva, Jaime; Méndez-Lucio, Oscar; Soria-Arteche, Olivia; Medina-Franco, José L

    2015-11-01

    Activity cliffs have large impact in drug discovery; therefore, their detection and quantification are of major importance. This work introduces the metric activity cliff enrichment factor and expands the previously reported activity cliff generator concept by adding chemotype information to representations of the activity landscape. To exemplify these concepts, three molecular databases with multiple biological activities were characterized. Compounds in each database were grouped into chemotype classes. Then, pairwise comparisons of structure similarities and activity differences were calculated for each compound and used to construct chemotype-based structure-activity similarity (SAS) maps. Different landscape distributions among four major regions of the SAS maps were observed for different subsets of molecules grouped in chemotypes. Based on this observation, the activity cliff enrichment factor was calculated to numerically detect chemotypes enriched in activity cliffs. Several chemotype classes were detected having major proportion of activity cliffs than the entire database. In addition, some chemotype classes comprising compounds with smooth structure activity relationships (SAR) were detected. Finally, the activity cliff generator concept was applied to compounds grouped in chemotypes to extract valuable SAR information.

  14. Atmospheric neutrino data Active-Active x Active-Sterile oscillations

    CERN Document Server

    Peres, O L G

    1998-01-01

    I summarize here the results of a global fit to the full data set corresponding to 33.0 kt-yr of data of the Super-Kamiokande experiment as well as to all other experiments in order to compare the active-active and active-sterile neutrinos oscillation channels to the atmospheric neutrino anomaly.

  15. UV activity indicators

    Science.gov (United States)

    Buccino, A. P.; Mauas, P. J. D.

    In Order to continue the work displayed in Buccino & Mauas(2003) and Buccino (2003), we have calculated the index Mg II (Xhk) on 1640 high resolution IUE spectra of 269 main sequence stars of spectral classes F, G and K. From this set of observations, we found an exponential relation between the continuum UV flux and the color (B-V). Contrary to Schrijver et al (1989), who assumed that the continuum UV flux depended on the color following the relation found by Rutten (1984) for the visible one, i.e. the logarithm of the flux is proportional to a polynomial of third order with the color. Nevertheless, the exponential relation flux in the continuous UV and the color (B-V) fits far better to our data that the given one by Rutten (1984). Obtained this dependency for the ultraviolet continuum flux, the index Xhk can be obtained from the single flux in the lines core, allowing to calculate the index of Mg II for those spectra where the continuum is very dark and so the relation signal noise is very low. As it were already reported in previous works (Rutten (1991), Schrijver (1992)), we found a minimum basal flux in the Mg II h and k lines core due to the cromospheric heating by disipation of acustics waves. From this minimum flux, we calculated minimum index of activity that satisfactorily fits to the minimum values of the indexes calculated on the 1640 spectra like quotient between the flux in the line core and the continuous one.

  16. Strategy as active waiting.

    Science.gov (United States)

    Sull, Donald N

    2005-09-01

    Successful executives who cut their teeth in stable industries or in developed countries often stumble when they face more volatile markets. They falter, in part, because they assume they can gaze deep into the future and develop a long-term strategy that will confer a sustainable competitive advantage. But visibility into the future of volatile markets is sharply limited because so many different variables are in play. Factors such as technological innovation, customers' evolving needs, government policy, and changes in the capital markets interact with one another to create unexpected outcomes. Over the past six years, Donald Sull, an associate professor at London Business School, has led a research project examining some of the world's most volatile markets, from national markets like China and Brazil to industries like enterprise software, telecommunications, and airlines. One of the most striking findings from this research is the importance of taking action during comparative lulls in the storm. Huge business opportunities are relatively rare; they come along only once or twice in a decade. And, for the most part, companies can't manufacture those opportunities; changes in the external environment converge to make them happen. What managers can do is prepare for these golden opportunities by managing smart during the comparative calm of business as usual. During these periods of active waiting, leaders must probe the future and remain alert to anomalies that signal potential threats or opportunities; exercise restraint to preserve their war chests; and maintain discipline to keep the troops battle ready. When a golden opportunity or"sudden death"threat emerges, managers must have the courage to declare the main effort and concentrate resources to seize the moment.

  17. Genotoxic activity of praziquantel.

    Science.gov (United States)

    Montero, R; Ostrosky, P

    1997-12-01

    Praziquantel is a synthetic drug with a remarkable activity against parasites, particularly treamatodes and cestodes. Initial genotoxicity tests used a spectrum of endpoints including tests in bacteria, yeasts, mammalian cells and Drosophila and each one gave negative results. Effects on reproductive cells of mice were negative as well. However, host mediated studies in mice and humans were contradictory and a comutagenic effect with several mutagens and carcinogens was found. Later studies, including monitoring in humans and pigs have shown that Praziquantel induces a greater frequency of hyperploid lymphocytes as well as structural chromosomal aberrations, but not in all the individuals treated. In vitro studies have demonstrated that Praziquantel can induce micronuclei in syrian hamster embryonic (SHE) cells and in lymphocytes of some individuals. The same was found about structural chromosomal aberrations. Fetal death and fetal resorption were found when Praziquantel was administered in high doses to pregnant rats between the 6th and 10th day of gestation. Due to its efficiency as a parasiticide, Praziquantel is in use in Latin-American, Asiatic, African and East-European countries where infections by trematodes and cestodes are frequent. However, the extensive use of Praziquantel in multiple reinfections, in non-infected and non-diagnosed individuals for prevention, in higher doses or repeated doses for cysticercosis treatment and in individuals exposed to environmental mutagens, in conjunction with new findings about its metabolism and genotoxic properties, make it necessary to further evaluate the potential of this drug not only to be mutagenic per se, but to contribute in the development of neoplasm.

  18. Active Beam Spectroscopy

    Science.gov (United States)

    von Hellermann, M. G.; Delabie, E.; Jaspers, R. J. E.; Biel, W.; Marchuk, O.; Summers, H. P.; Whiteford, A.; Giroud, C.; Hawkes, N. C.; Zastrow, K. D.

    2008-03-01

    Charge eXchange Recombination Spectroscopy (CXRS) plays a pivotal role in the diagnostics of hot fusion plasmas and is implemented currently in most of the operating devices. In the present report the main features of CXRS are summarized and supporting software packages encompassing "Spectral Analysis Code CXSFIT", "Charge Exchange Analysis Package CHEAP", and finally "Forward Prediction of Spectral Features" are described. Beam Emission Spectroscopy (BES) is proposed as indispensable cross-calibration tool for absolute local impurity density measurements and also for the continuous monitoring of the neutral beam power deposition profile. Finally, a full exploitation of the `Motional Stark Effect' pattern is proposed to deduce local pitch angles, total magnetic fields and possibly radial electric fields. For the proposed active beam spectroscopy diagnostic on ITER comprehensive performance studies have been carried out. Estimates of expected spectral signal-to-noise ratios are based on atomic modelling of neutral beam stopping and emissivities for CXRS, BES and background continuum radiation as well as extrapolations from present CXRS diagnostic systems on JET, Tore Supra, TEXTOR and ASDEX-UG. Supplementary to thermal features a further promising application of CXRS has been proposed recently for ITER, that is a study of slowing-down alpha particles in the energy range up to 2 MeV making use of the 100 keV/amu DNB (Diagnostic Neutral Beam) and the 500 keV/amu HNB (Heating Neutral Beam). Synthetic Fast Ion Slowing-Down spectra are evaluated in terms of source rates and slowing-down parameters

  19. IDENTIFICATION AND ECOPHYSIOLOGY OF ACTIVE DENITRIFIERS IN ACTIVATED SLUDGE

    DEFF Research Database (Denmark)

    Hansen, Aviaja Anna; Le-Quy, Vang; Nielsen, Kåre Lehmann;

    and when external carbon sources were supplemented to the activated sludge the composition of the denitrifying communities was significantly affected. Transcriptome profiling provided detailed insight in the metabolic pathways in several of the active denitrifiers in activated sludge. In conclusion...... reactor studies. To obtain better identification of active denitrifying communities in full-scale wastewater treatment plants (WWTPs) we applied DNA-SIP with 13C-labelled substrates, and RT-PCR of expressed denitrification genes (nirS, nirK and nosZ) upon various substrate-inductions. To come around...... were determined with quantitative FISH, while their active metabolic pathways were investigated directly in activated sludge with a tag-based metatranscriptomic approach under acetate-utilizing and denitrifying conditions. The different methods revealed a majority of denitrifiers in all WWTPs belonging...

  20. Fluidization and Active Thinning by Molecular Kinetics in Active Gels.

    Science.gov (United States)

    Oriola, David; Alert, Ricard; Casademunt, Jaume

    2017-02-24

    We derive the constitutive equations of an active polar gel from a model for the dynamics of elastic molecules that link polar elements. Molecular binding kinetics induces the fluidization of the material, giving rise to Maxwell viscoelasticity and, provided that detailed balance is broken, to the generation of active stresses. We give explicit expressions for the transport coefficients of active gels in terms of molecular properties, including nonlinear contributions on the departure from equilibrium. In particular, when activity favors linker unbinding, we predict a decrease of viscosity with activity-active thinning-of kinetic origin, which could explain some experimental results on the cell cortex. By bridging the molecular and hydrodynamic scales, our results could help understand the interplay between molecular perturbations and the mechanics of cells and tissues.

  1. Negotiating active ageing at a Danish activity centre

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    and practices active ageing. The paper uses an activity centre in Copenhagen as its site of negotiation. Methods: These questions have been explored with the use of ethnographic fieldwork and through a documentary study. The ethnographic fieldwork has been conducted at an activity centre with 4 months...... of participatory observation in 2011 and 2012, as well as 11 semi-structured, in-depth interviews with users of the centre. 4 of these users have been followed around during everyday activities such as doing groceries, picking up grandchildren, etc. The documentary study consists of documents and statements...

  2. Activated coconut shell charcoal carbon using chemical-physical activation

    Science.gov (United States)

    Budi, Esmar; Umiatin, Nasbey, Hadi; Bintoro, Ridho Akbar; Wulandari, Futri; Erlina

    2016-02-01

    The use of activated carbon from natural material such as coconut shell charcoal as metal absorbance of the wastewater is a new trend. The activation of coconut shell charcoal carbon by using chemical-physical activation has been investigated. Coconut shell was pyrolized in kiln at temperature about 75 - 150 °C for about 6 hours in producing charcoal. The charcoal as the sample was shieved into milimeter sized granule particle and chemically activated by immersing in various concentration of HCl, H3PO4, KOH and NaOH solutions. The samples then was physically activated using horizontal furnace at 400°C for 1 hours in argon gas environment with flow rate of 200 kg/m3. The surface morphology and carbon content of activated carbon were characterized by using SEM/EDS. The result shows that the pores of activated carbon are openned wider as the chemical activator concentration is increased due to an excessive chemical attack. However, the pores tend to be closed as further increasing in chemical activator concentration due to carbon collapsing.

  3. Production and characterization of granular activated carbon from activated sludge

    Directory of Open Access Journals (Sweden)

    Z. Al-Qodah

    2009-03-01

    Full Text Available In this study, activated sludge was used as a precursor to prepare activated carbon using sulfuric acid as a chemical activation agent. The effect of preparation conditions on the produced activated carbon characteristics as an adsorbent was investigated. The results indicate that the produced activated carbon has a highly porous structure and a specific surface area of 580 m²/g. The FT-IR analysis depicts the presence of a variety of functional groups which explain its improved adsorption behavior against pesticides. The XRD analysis reveals that the produced activated carbon has low content of inorganic constituents compared with the precursor. The adsorption isotherm data were fitted to three adsorption isotherm models and found to closely fit the BET model with R² equal 0.948 at pH 3, indicating a multilayer of pesticide adsorption. The maximum loading capacity of the produced activated carbon was 110 mg pesticides/g adsorbent and was obtained at this pH value. This maximum loading was found experimentally to steeply decrease as the solution pH increases. The obtained results show that activated sludge is a promising low cost precursor for the production of activated carbon.

  4. Silicon active photonic devices

    Science.gov (United States)

    Dimitropoulos, Dimitrios

    Active photonic devices utilizing the optical nonlinearities of silicon have emerged in the last 5 years and the effort for commercial photonic devices in the material that has been the workhorse of electronics has been building up since. This dissertation presents the theory for some of these devices. We are concerned herein with CW lasers, amplifiers and wavelength converters that are based on the Raman effect. There have already been cursory experimental demonstrations of these devices and some of their limitations are already apparent. Most of the limitations observed are because of the appearance of effects that are competing with stimulated Raman scattering. Under the high optical powers that are necessary for the Raman effect (tens to hundrends of mW's) the process of optical two-photon (TPA) absorption occurs. The absorption of optical power that it causes itself is weak but in the process electrons and holes are generated which can further absorb light through the free-carrier absorption effect (FCA). The effective "lifetime" that these carriers have determines the magnitude of the FCA loss. We present a model for the carrier lifetime in Silicon-On-Insulator (SOI) waveguides and numerical simulations to understand how this critical parameter varies and how it can be controlled. A p-i-n junction built along SOI waveguides can help achieve lifetime of the order of 20--100 ps but the price one has to pay is on-chip electrical power consumption on the order of 100's of mWs. We model CW Raman lasers and we find that the carrier lifetime reduces the output power. If the carrier lifetime exceeds a certain "critical" value optical losses become overwhelming and lasing is impossible. As we show, in amplifiers, the nonlinear loss does not only result in diminished gain, but also in a higher noise figure. Finally the effect of Coherent anti-Stokes Raman scattering (CARS) is examined. The effect is important because with a pump frequency at 1434nm coherent power

  5. Permanent active longitudes and activity cycles on RS CVn stars

    Science.gov (United States)

    Berdyugina, Svetlana V.; Tuominen, Ilkka

    1998-08-01

    A new analysis of the published long-term photometric observations has revealed permanent active-longitude structures in four RS CVn stars: EI Eri, II Peg, sigma Gem, and HR 7275. Two active longitudes separated by half of the period are found to dominate on the surface during all available seasons. The positions of the longitudes on three stars (EI Eri, II Peg, HR 7275) are migrating in the orbital reference frame, and there is no preferred orientation with respect to the line of centres in the binaries. The rate of migration is approximately constant. In case of sigma Gem the active longitude migration is synchronized with the orbital motion in the direction of the line of centres in the binary. The active region lifetimes can be longer than the time span of the observations (>=15 yr). The periods of the active longitude rotation are determined: for EI Eri 1fd 9510, for II Peg 6fd 7066, for sigma Gem 19fd 604, for HR 7275 28fd 263. Long-term activity cycles of the stars are discovered from the analysis of the relative contribution of the two longitudes to the photometric variability. One longitude is found to be usually more active than the other at a given moment, and the change of the activity level between the longitudes is cyclic with periods of years. The switch of the activity takes a much shorter time, about a few months, similar to the ``flip-flop'' phenomenon found for FK Com stars. Moments of switching are regarded as new tracers of the activity, and total cycles, which return activity to the same longitude, are found to be for EI Eri 9.0 yr, for II Peg 9.3 yr, for sigma Gem 14.9 yr, for HR 7275 17.5 yr.

  6. Tyrosine phosphorylation of NEDD4 activates its ubiquitin ligase activity.

    Science.gov (United States)

    Persaud, Avinash; Alberts, Philipp; Mari, Sara; Tong, Jiefei; Murchie, Ryan; Maspero, Elena; Safi, Frozan; Moran, Michael F; Polo, Simona; Rotin, Daniela

    2014-10-07

    Ligand binding to the receptor tyrosine kinase fibroblast growth factor (FGF) receptor 1 (FGFR1) causes dimerization and activation by transphosphorylation of tyrosine residues in the kinase domain. FGFR1 is ubiquitylated by the E3 ligase NEDD4 (also known as NEDD4-1), which promotes FGFR1 internalization and degradation. Although phosphorylation of FGFR1 is required for NEDD4-dependent endocytosis, NEDD4 directly binds to a nonphosphorylated region of FGFR1. We found that activation of FGFR1 led to activation of c-Src kinase-dependent tyrosine phosphorylation of NEDD4, enhancing the ubiquitin ligase activity of NEDD4. Using mass spectrometry, we identified several FGF-dependent phosphorylated tyrosines in NEDD4, including Tyr(43) in the C2 domain and Tyr(585) in the HECT domain. Mutating these tyrosines to phenylalanine to prevent phosphorylation inhibited FGF-dependent NEDD4 activity and FGFR1 endocytosis and enhanced cell proliferation. Mutating the tyrosines to glutamic acid to mimic phosphorylation enhanced NEDD4 activity. Moreover, the NEDD4 C2 domain bound the HECT domain, and the presence of phosphomimetic mutations inhibited this interaction, suggesting that phosphorylation of NEDD4 relieves an inhibitory intra- or intermolecular interaction. Accordingly, activation of FGFR1 was not required for activation of NEDD4 that lacked its C2 domain. Activation of c-Src by epidermal growth factor (EGF) also promoted tyrosine phosphorylation and enhanced the activity of NEDD4. Thus, we identified a feedback mechanism by which receptor tyrosine kinases promote catalytic activation of NEDD4 and that may represent a mechanism of receptor crosstalk.

  7. CDPK Activation in PRR Signaling.

    Science.gov (United States)

    Seybold, Heike; Boudsocq, Marie; Romeis, Tina

    2017-01-01

    Calcium-dependent protein kinases undergo a rapid biochemical activation in response to an intracellular Ca increase induced by the PRR-dependent perception of a pathogen-related stimulus. Based on SDS gel resolution, the in-gel kinase assay allows the analysis of multiple in vivo protein samples in parallel, combining the advantage of protein separation according to molecular mass with the activity read-out of a protein kinase assay. It thus enables to follow the transient CDPK activation and inactivation in response to in vivo elicitation with a time-wise resolution. In addition, changes of CDPK phosphorylation activity often correlate with slight shifts in the enzyme's apparent molecular mass, indicating posttranslational modifications and a conformational change of the active enzyme compared to its inactive resting form. These band shifts can be detected by a simple immunoblotting to monitor CDPK activation.

  8. Swim pressure of active matter

    Science.gov (United States)

    Takatori, Sho; Yan, Wen; Brady, John; Caltech Team

    2014-11-01

    Through their self-motion, all active matter systems generate a unique ``swim pressure'' that is entirely athermal in origin. This new source for the active stress exists at all scales in both living and nonliving active systems, and also applies to larger organisms where inertia is important (i.e., the Stokes number is not small). Here we explain the origin of the swim stress and develop a simple thermodynamic model to study the self-assembly and phase separation in active soft matter. Our new swim stress perspective can help analyze and exploit a wide class of active soft matter, from swimming bacteria and catalytic nanobots, schools of fish and birds, and molecular motors that activate the cellular cytoskeleton.

  9. Enhanced NIF neutron activation diagnostics.

    Science.gov (United States)

    Yeamans, C B; Bleuel, D L; Bernstein, L A

    2012-10-01

    The NIF neutron activation diagnostic suite relies on removable activation samples, leading to operational inefficiencies and a fundamental lower limit on the half-life of the activated product that can be observed. A neutron diagnostic system measuring activation of permanently installed samples could remove these limitations and significantly enhance overall neutron diagnostic capabilities. The physics and engineering aspects of two proposed systems are considered: one measuring the (89)Zr/(89 m)Zr isomer ratio in the existing Zr activation medium and the other using potassium zirconate as the activation medium. Both proposed systems could improve the signal-to-noise ratio of the current system by at least a factor of 5 and would allow independent measurement of fusion core velocity and fuel areal density.

  10. Catalytic activity of Au nanoparticles

    DEFF Research Database (Denmark)

    Larsen, Britt Hvolbæk; Janssens, Ton V.W.; Clausen, Bjerne;

    2007-01-01

    Au is usually viewed as an inert metal, but surprisingly it has been found that Au nanoparticles less than 3–5 nm in diameter are catalytically active for several chemical reactions. We discuss the origin of this effect, focusing on the way in which the chemical activity of Au may change with par......Au is usually viewed as an inert metal, but surprisingly it has been found that Au nanoparticles less than 3–5 nm in diameter are catalytically active for several chemical reactions. We discuss the origin of this effect, focusing on the way in which the chemical activity of Au may change...... with particle size. We find that the fraction of low-coordinated Au atoms scales approximately with the catalytic activity, suggesting that atoms on the corners and edges of Au nanoparticles are the active sites. This effect is explained using density functional calculations....

  11. Social activity and healthy aging

    DEFF Research Database (Denmark)

    McGue, Matt; Christensen, Kaare

    2007-01-01

    with late-life physical functioning, cognitive functioning, and depression symptomatology using data from 1112 pairs of like-sex twins who participated in the Longitudinal Study of Aging Danish Twins. Consistent with previous research, we found that social activity was significantly correlated with overall...... level of physical functioning, cognitive functioning, and depression symptomatology. We also found that social activity was significantly and moderately heritable (estimate of .36), raising the possibility that its association with late-life functioning might reflect selection processes. Further, social...... activity did not predict change in functioning and in monozygotic twin pairs discordant on level of social activity, the more socially active twin was not less susceptible to age decreases in physical and cognitive functioning and increases in depression symptomatology than the less socially active twin...

  12. Activated sludge inhibition capacity index

    Directory of Open Access Journals (Sweden)

    V. Surerus

    2014-06-01

    Full Text Available Toxic compounds in sewage or industrial wastewater may inhibit the biological activity of activated sludge impairing the treatment process. This paper evaluates the Inhibition Capacity Index (ICI for the assessment of activated sludge in the presence of toxicants. In this study, activated sludge was obtained from industrial treatment plants and was also synthetically produced. Continuous respirometric measurements were carried out in a reactor, and the oxygen uptake rate profile obtained was used to evaluate the impact of inhibiting toxicants, such as dissolved copper, phenol, sodium alkylbenzene sulfonate and amoxicillin, on activated sludge. The results indicate that ICI is an efficient tool to quantify the intoxication capacity. The activated sludge from the pharmaceutical industry showed higher resistance than the sludge from other sources, since toxicants are widely discharged in the biological treatment system. The ICI range was from 58 to 81% when compared to the synthetic effluent with no toxic substances.

  13. Japanese activities in refrigeration technology

    Science.gov (United States)

    Fujita, T.; Ohtsuka, T.; Ishizaki, Y.

    This paper reviews recent activities in refrigeration technology in Japan. The projects described are stimulated by growing industrial needs or form part of large national projects. The JNR project on the MAGLEV train is currently the most powerful activity and it demands knowledge in all the different disciplines of cryogenics in particular on various scales of refrigeration. Research activities are also directed towards the development of Stirling cycle and magnetic refrigerators for applications in a wider area.

  14. L3 Study Team Activities

    Science.gov (United States)

    Shoemaker, David; L3ST Team

    2017-01-01

    The NASA-Chartered L3 Study Team is working to develop the US community participation and to support NASA's contribution to the ESA-led LISA mission to observe gravitational waves via space-based detectors. The present activities of the L3ST will be described, and the next steps for the Study Team will also be given. NASA supports travel activities and support for the Study Team activities.

  15. INNOVATIONS AND TOURISTIC ACTIVITY EVOLUTION

    Directory of Open Access Journals (Sweden)

    V. S. Novikov

    2012-01-01

    Full Text Available Fundamental and applied innovations impact activities in the tourist industry and evolution thereof. More and more sophisticated technologies and communication techniques are practically used to serve tourists. Basically, innovative tourist activity development concept represents innovation of values and in particular means that tourist’s impression is taken into account to higher extent and tourist product personification changes the products’ consumer value. Discussed in the article are tourist activity, tourist cluster, destination and glocalization development prospects.

  16. Activity Recognition in Social Media

    Science.gov (United States)

    2015-12-29

    activity is splitting. 6 Crowd video classification Ability to identify crowd behavior enables crowd management systems to design and manage public...characterize group activities . We then showed the effectiveness of group level features in crowd video classification . 9 List of Publications 1. N. Bhargava, S...AFRL-AFOSR-JP-TR-2016-0044 Activity Recognition in Social Media Subhasis Chaudhuri INDIAN INSTITUTE OF TECHNOLOGY BOMBAY Final Report 05/09/2016

  17. Activating Teaching for Quality Learning

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy

    2013-01-01

    Activating teaching is an educational concept which is based on active participation of students in the study process. It is becoming an alternative to more typical approach where the teacher will just lecture and the students will take notes. The study described in this paper considers student...... activating teaching methods focusing on those based on knowledge dissemination. The practical aspects of the implemented teaching method are considered, and employed assessment methods and tools are discussed....

  18. Spanish Young Generation (JJNN) Activities

    Energy Technology Data Exchange (ETDEWEB)

    Millan, Miguel [INITEC Nuclear- Westinghouse, Padilla 17, 28006 Madrid (Spain)

    2008-07-01

    Spanish Young Generation has been very active during 2006-2008. JJNN have mainly focused on communication activities, as conferences at universities, schools and nuclear companies. Lately, becoming in referent of the young politics, journalist and the young people in Nuclear Subjects is the new and most challenging target of the Spanish Young Generation. In order to accomplish with their objects and commitments with their members, JJNN are developing all kinds of activities focused in the young people and the JJNN members. (authors)

  19. Architectural Design Activities for JAS

    CERN Document Server

    Khaled, Lena

    2009-01-01

    The critical part for building any software system is its architecture. Architectural design is a design at a higher level of abstraction. A good architecture ensures that software will satisfy its requirement. This paper defines the most important activities of architectural design that used through building any software; also it applies these activities on one type of Electronic Commerce (EC) applications that is Job Agency System(JAS) to show how these activities can work through these types of applications.

  20. Biological Activities of Hydrazone Derivatives

    Directory of Open Access Journals (Sweden)

    S. Güniz Küçükgüzel

    2007-08-01

    Full Text Available There has been considerable interest in the development of novel compounds with anticonvulsant, antidepressant, analgesic, antiinflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and antischistosomiasis activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazones that possess varied biological activities.

  1. Active Combustion Control Valve Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the...

  2. Studies in geophysics: Active tectonics

    Science.gov (United States)

    1986-01-01

    Active tectonics is defined within the study as tectonic movements that are expected to occur within a future time span of concern to society. Such movements and their associated hazards include earthquakes, volcanic eruptions, and land subsidence and emergence. The entire range of geology, geophysics, and geodesy is, to some extent, pertinent to this topic. The needs for useful forecasts of tectonic activity, so that actions may be taken to mitigate hazards, call for special attention to ongoing tectonic activity. Further progress in understanding active tectonics depends on continued research. Particularly important is improvement in the accuracy of dating techniques for recent geologic materials.

  3. Physical Activity in the Classroom

    DEFF Research Database (Denmark)

    Réol, Lise Andersen

    2016-01-01

    physical activity during each school day from 0th to 10th school year, as a tool to facilitate health, motivation and academic performance. A qualitative study on pupils in 6th grade (N=8) and teachers’ (N=3) experience of movement and physical activities in school gives support to the idea, that physical...... activities in school enhance positive emotions and support an inclusive and safe learning environment. Thought it does also point to the fact, that it is indeed not that simple. Teachers’ sport-specific educational competences, their own experience of well-being and fun related to physical activities...

  4. THERMAL ACTIVATION OF IMMOBILIZED PAPAIN

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Papain (Papainase, EC 3.4.22.2) was immobilized on porous silica beads by cross linking with glutaraldehyde. The thermal activation of this immobilized papain in aqueous system was found at a temperature range from 50 to 90℃. The higher the temperature, the more active the immobilized papain will possess. At the same time,the durability of the immobilized papain on heating was greatly improved. The effect of additives and salts on the activity of the immobilized papain were also studied. The results showed that the additives and some of the salts studied could markedly enhance the activity of the immobilized papain at elevated temperature.

  5. CDBG Activity Funding by Tract

    Data.gov (United States)

    Department of Housing and Urban Development — All CDBG activities in the categories of acquisition, economic development, housing, public improvements, public services, and other summarized by Census Tract.

  6. Physical activity and human health

    Directory of Open Access Journals (Sweden)

    Paulina Wojciechowska

    2015-01-01

    Full Text Available Introduction: The dynamic development of the automotive industry, transport, and the media means that human life has become much easier. At the same time, the comfortable living conditions have decreased physical activity. Biologically conditioned, the need of activity has been minimised by the ever-increasing pace of life. As a result, it may lead to the loss of physical and mental health. Active recreation is not only an excellent source of activity, but also a source of satisfaction. Youths and adults should therefore spend their free time primarily on various forms of physical activity. Aim of the research : To evaluate the physical fitness of students who regularly practice physical exercise, those who occasionally practice, and those not practicing any form of physical activity. Material and methods : In the research we used a questionnaire of the Ruffier test and an orthostatic test. The study involved a group of 15 people aged 20–25 years. Participation in the study was entirely voluntary and anonymous. The study group consisted only of women. Results obtained from the questionnaire survey were fully reflected during exercise tests performed. Results and conclusions: Only regularly practiced physical activity has an effect on our body. Regular exercise increases our body’s physical capacity. Activity is the best means of prevention of lifestyle diseases. Youths and adults should spend their free time mainly doing various forms of physical activity.

  7. Active Combustion Control Valve Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the operational...

  8. Active Gas Regenerative Liquefier Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We offer a novel liquefier that has the potential to simultaneously increase thermodynamic efficiency and significantly reduce complexity. The ?active gas...

  9. Active Directory Designing, Deploying, and Running Active Directory

    CERN Document Server

    Desmond, Brian

    2008-01-01

    By giving you a thorough grounding in Active Directory, this bestselling book teaches you how to design, manage, and maintain an AD infrastructure, whether it's for a small business network or a multinational enterprise with thousands of resources, services, and users. The fourth edition covers Active Directory from Windows 2000 through Windows Server 2008 in an easy-to-understand narrative style.

  10. Incorporation of Socio-scientific Content into Active Learning Activities

    Science.gov (United States)

    King, D. B.; Lewis, J. E.; Anderson, K.; Latch, D.; Sutheimer, S.; Webster, G.; Moog, R.

    2014-12-01

    Active learning has gained increasing support as an effective pedagogical technique to improve student learning. One way to promote active learning in the classroom is the use of in-class activities in place of lecturing. As part of an NSF-funded project, a set of in-class activities have been created that use climate change topics to teach chemistry content. These activities use the Process Oriented Guided Inquiry Learning (POGIL) methodology. In this pedagogical approach a set of models and a series of critical thinking questions are used to guide students through the introduction to or application of course content. Students complete the activities in their groups, with the faculty member as a facilitator of learning. Through assigned group roles and intentionally designed activity structure, process skills, such as teamwork, communication, and information processing, are developed during completion of the activity. Each of these climate change activities contains a socio-scientific component, e.g., social, ethical and economic data. In one activity, greenhouse gases are used to explain the concept of dipole moment. Data about natural and anthropogenic production rates, global warming potential and atmospheric lifetimes for a list of greenhouse gases are presented. The students are asked to identify which greenhouse gas they would regulate, with a corresponding explanation for their choice. They are also asked to identify the disadvantages of regulating the gas they chose in the previous question. In another activity, where carbon sequestration is used to demonstrate the utility of a phase diagram, students use economic and environmental data to choose the best location for sequestration. Too often discussions about climate change (both in and outside the classroom) consist of purely emotional responses. These activities force students to use data to support their arguments and hypothesize about what other data could be used in the corresponding discussion to

  11. Active vibration and noise control by hybrid active acoustic panels

    Energy Technology Data Exchange (ETDEWEB)

    Stoebener, U.; Gaul, L. [Stuttgart Univ. (Germany). Inst. A fuer Mechanik

    2001-07-01

    In the present paper a hybrid passive and active treatment for vibration and noise reduction of plate type structures is proposed. The treatment is manufactured as sandwich structure and is called hybrid active acoustic panel. The passive component is used to reduce the vibration and sound radiation for high frequencies whereas the active part of the system is designed for the low frequency range. By selecting the thickness of the passive damping layer a certain frequency limit is defined, which divides the high and low frequency range. The actuator and sensor layout of the active component is evaluated by using the mode shapes of the low frequency range. According to the evaluated layout a hybrid active acoustic panel is manufactured and experimentally tested. The experimental results validate the proposed concept. (orig.)

  12. Protease activities of rumen protozoa.

    Science.gov (United States)

    Forsberg, C W; Lovelock, L K; Krumholz, L; Buchanan-Smith, J G

    1984-01-01

    Intact, metabolically active rumen protozoa prepared by gravity sedimentation and washing in a mineral solution at 10 to 15 degrees C had comparatively low proteolytic activity on azocasein and low endogenous proteolytic activity. Protozoa washed in 0.1 M potassium phosphate buffer (pH 6.8) at 4 degrees C and stored on ice autolysed when they were warmed to 39 degrees C. They also exhibited low proteolytic activity on azocasein, but they had a high endogenous proteolytic activity with a pH optimum of 5.8. The endogenous proteolytic activity was inhibited by cysteine proteinase inhibitors, for example, iodoacetate (63.1%) and the aspartic proteinase inhibitor, pepstatin (43.9%). Inhibitors specific for serine proteinases and metalloproteinases were without effect. The serine and cysteine proteinase inhibitors of microbial origin, including antipain, chymostatin, and leupeptin, caused up to 67% inhibition of endogenous proteolysis. Hydrolysis of casein by protozoa autolysates was also inhibited by cysteine proteinase inhibitors. Some of the inhibitors decreased endogenous deamination, in particular, phosphoramidon, which had little inhibitory effect on proteolysis. Protozoal and bacterial preparations exhibited low hydrolytic activities on synthetic proteinase and carboxypeptidase substrates, although the protozoa had 10 to 78 times greater hydrolytic activity (per milligram of protein) than bacteria on the synthetic aminopeptidase substrates L-leucine-p-nitroanilide, L-leucine-beta-naphthylamide, and L-leucinamide. The aminopeptidase activity was partially inhibited by bestatin. It was concluded that cysteine proteinases and, to a lesser extent, aspartic proteinases are primarily responsible for proteolysis in autolysates of rumen protozoa. The protozoal autolysates had high aminopeptidase activity; low deaminase activity was observed on endogenous amino acids. PMID:6364968

  13. NSLS 2009 Activity Report

    Energy Technology Data Exchange (ETDEWEB)

    Nasta K.; Mona R.

    2009-05-01

    2009 was an incredibly exciting year for light sources at Brookhaven. The National Synchrotron Light Source (NSLS) hosted more than 2,200 visiting researchers, who, along with the about 50 members of our scientific staff, produced a total of 957 publications - about 20 percent of which appeared in premier journals. Covering topics ranging from Alzheimer's disease detection to ethanol-powered fuel cells, a sampling of these findings can be found in this Activity Report. We've also seen the resurfacing of some of our long-time users hard work. I was very proud to hear that two of the three recipients of the 2009 Nobel Prize in Chemistry have ties to the NSLS. Venki Ramakrishnan, a former employee in Brookhaven's biology department and long-time user of the NSLS, now at Cambridge University, and Thomas A. Steitz of Yale University, also a long-time NSLS user, shared the prize with Ada E. Yonath of the Weizmann Institute of Science for their work on the structure and function of the ribosome. In the late 1990s, Ramakrishnan and Steitz used protein crystallography at the NSLS to gather atomic-level images of two ribosome subunits: 30S (Ramakrishnan) and 50S (Steitz). Both laureates solved the high-resolution structures for these subunits based on this data. After struggling with a rough budget for several years, we received excellent funding, and then some, this year. In addition to NSLS operations funding, we received $3 million in funds from the American Recovery and Reinvestment Act (ARRA). We used that additional money for two exciting projects: construction of a full-field x-ray microscope and acquisition of several advanced x-ray detectors. The x-ray microscope will be able to image objects with a targeted spatial resolution of 30 nanometers. This capability will be particularly important for new initiatives in energy research and will prepare our users for the projected 1-nanometer resolution benchmark at the National Synchrotron Light Source II

  14. NSLS 2009 Activity Report

    Energy Technology Data Exchange (ETDEWEB)

    Nasta K.; Mona R.

    2009-05-01

    2009 was an incredibly exciting year for light sources at Brookhaven. The National Synchrotron Light Source (NSLS) hosted more than 2,200 visiting researchers, who, along with the about 50 members of our scientific staff, produced a total of 957 publications - about 20 percent of which appeared in premier journals. Covering topics ranging from Alzheimer's disease detection to ethanol-powered fuel cells, a sampling of these findings can be found in this Activity Report. We've also seen the resurfacing of some of our long-time users hard work. I was very proud to hear that two of the three recipients of the 2009 Nobel Prize in Chemistry have ties to the NSLS. Venki Ramakrishnan, a former employee in Brookhaven's biology department and long-time user of the NSLS, now at Cambridge University, and Thomas A. Steitz of Yale University, also a long-time NSLS user, shared the prize with Ada E. Yonath of the Weizmann Institute of Science for their work on the structure and function of the ribosome. In the late 1990s, Ramakrishnan and Steitz used protein crystallography at the NSLS to gather atomic-level images of two ribosome subunits: 30S (Ramakrishnan) and 50S (Steitz). Both laureates solved the high-resolution structures for these subunits based on this data. After struggling with a rough budget for several years, we received excellent funding, and then some, this year. In addition to NSLS operations funding, we received $3 million in funds from the American Recovery and Reinvestment Act (ARRA). We used that additional money for two exciting projects: construction of a full-field x-ray microscope and acquisition of several advanced x-ray detectors. The x-ray microscope will be able to image objects with a targeted spatial resolution of 30 nanometers. This capability will be particularly important for new initiatives in energy research and will prepare our users for the projected 1-nanometer resolution benchmark at the National Synchrotron Light Source II

  15. Leisure activities, time and environment

    DEFF Research Database (Denmark)

    Røpke, Inge; Godskesen, Mirjam Irene

    2007-01-01

    The intention of this paper is to explore the relationships between leisure activities and the environment. Most research on leisure is unrelated to environmental issues, but when this research is “read” through environmental “glasses”, it provides relevant inputs for environmental studies...... use and activities rather than various categories of consumer spending....

  16. Developing Internal Controls through Activities

    Science.gov (United States)

    Barnes, F. Herbert

    2009-01-01

    Life events can include the Tuesday afternoon cooking class with the group worker or the Saturday afternoon football game, but in the sense that Fritz Redl thought of them, these activities are only threads in a fabric of living that includes all the elements of daily life: playing, working, school-based learning, learning through activities,…

  17. MNC Headquarters as Activity Systems

    DEFF Research Database (Denmark)

    Nell, Phillip C.; Larsen, Marcus M.

    Recent literature has questioned why multinational corporations (MNC) relocate their headquarters activities overseas. In this paper, we investigate the consequences of this phenomenon. To do this, we conceptualize the MNC headquarters activities as an interdependent system, and develop a set of ...

  18. MNC Headquarters as Activity Systems

    DEFF Research Database (Denmark)

    Nell, Phillip C.; Møller Larsen, Marcus

    2012-01-01

    Recent literature has questioned why multinational corporations (MNC) relocate their headquarters activities overseas. In this paper, we investigate the consequences of this phenomenon. To do this, we conceptualize the MNC headquarters activities as an interdependent system, and develop a set of ...

  19. Antimicrobial activity of Securidaca longipedunculata.

    Science.gov (United States)

    Ajali, U; Chukwurah, B K C

    2004-11-01

    The folk herbal uses of Securidaca longipedunculata in the treatment of diarrhea, boils, gonorrhea, and cough prompted phytochemical analyses and antimicrobial activity screening of extracts of the root. Some flavonoids isolated showed activity against many micro-organisms. These flavonoids were isolated using chromatographic methods.

  20. Coal Activities for Secondary Students.

    Science.gov (United States)

    American Coal Foundation, Washington, DC.

    This collection of lesson plans designed for teachers of 4th- through 12th-grade students utilizes an assortment of teaching strategies for topics related to coal and the coal industry. Activities cover the following topics: coal formation; coal identification; "the geologist's dilemma" (a supply and demand activity); geologic time and the…

  1. Physical Activity and Academic Achievement

    Centers for Disease Control (CDC) Podcasts

    2014-12-09

    This podcast highlights the evidence that supports the link between physical activity and improved academic achievement. It also identifies a few actions to support a comprehensive school physical activity program to improve academic achievement.  Created: 12/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 12/9/2014.

  2. FORECASTING NEED IN ORGANIZATION ACTIVITY

    Directory of Open Access Journals (Sweden)

    Luminiţa Danciu

    2012-12-01

    Full Text Available Inside a company activity planning is made according to estimates. This means that estimates are very important. If estimates are wrong the company's activity will be on the wrong way. In the management zone in order to focus on general objectives achievement there are used estimates and forecasting methods.

  3. Event-Based Activity Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2004-01-01

    We present and discuss a modeling approach that supports event-based modeling of information and activity in information systems. Interacting human actors and IT-actors may carry out such activity. We use events to create meaningful relations between information structures and the related activit...

  4. Making Behavioral Activation More Behavioral

    Science.gov (United States)

    Kanter, Jonathan W.; Manos, Rachel C.; Busch, Andrew M.; Rusch, Laura C.

    2008-01-01

    Behavioral Activation, an efficacious treatment for depression, presents a behavioral theory of depression--emphasizing the need for clients to contact positive reinforcement--and a set of therapeutic techniques--emphasizing provision of instructions rather than therapeutic provision of reinforcement. An integration of Behavioral Activation with…

  5. Interdisciplinarity in Adapted Physical Activity

    Science.gov (United States)

    Bouffard, Marcel; Spencer-Cavaliere, Nancy

    2016-01-01

    It is commonly accepted that inquiry in adapted physical activity involves the use of different disciplines to address questions. It is often advanced today that complex problems of the kind frequently encountered in adapted physical activity require a combination of disciplines for their solution. At the present time, individual research…

  6. An Application of Activity Theory

    Science.gov (United States)

    Marken, James A.

    2006-01-01

    Activity Theory has often been used in workplace settings to gain new theoretical understandings about work and the humans who engage in work, but rarely has there been sufficient detail in the literature to allow HPT practitioners to do their own activity analysis. The detail presented in this case is sufficient for HPT practitioners to begin to…

  7. Generic active appearance models revisited

    NARCIS (Netherlands)

    Tzimiropoulos, Georgios; Alabort-i-Medina, Joan; Zafeiriou, Stefanos; Pantic, Maja

    2012-01-01

    The proposed Active Orientation Models (AOMs) are gen- erative models of facial shape and appearance. Their main dierences with the well-known paradigm of Active Appearance Models (AAMs) are (i) they use a dierent statistical model of appearance, (ii) they are accompanied by a robust algorithm for m

  8. Physical Activity and Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Vincenzo Bellizzi

    2014-07-01

    Full Text Available Renal transplantation is burdened by high cardiovascular risk because of increased prevalence of traditional and disease-specific cardiovascular risk factors and, consequently, patients are affected by greater morbidity and mortality. In renal transplanted patients, healthy lifestyle and physical activity are recommended to improve overall morbidity and cardiovascular outcomes. According to METs (Metabolic Equivalent Task; i.e. the amount of energy consumed while sitting at rest, physical activities are classified as sedentary (<3.0 METs, of moderate-(3.0 to 5.9 METs or vigorous-intensity (≥6.0 METs. Guidelines suggest for patients with chronic kidney disease an amount of physical activity of at least 30 minutes of moderate-intensity activity five times per week (min 450 MET-minutes/week. Data on physical activity in renal transplanted patients, however, are limited and have been mainly obtained by mean of non-objective methods. Available data suggest that physical activity is low either at the start or during renal transplantation and this may be associated with poor patient and graft outcomes. Therefore, in renal transplanted patients more data on physical activity obtained with objective, accelerometer-based methods are needed. In the meanwhile, physical activity have to be considered as an essential part of the medical care for renal transplanted recipients.

  9. Designing active objects in DEGAS

    NARCIS (Netherlands)

    Akker, J.F.P. van den; Siebes, A.P.J.M.

    1997-01-01

    This report discusses application design for active databases, in particular for the active object-based database programming language DEGAS. In DEGAS one modularisation principle, the object, is applied to all elements of the application, including rules. We discuss a design process consisting of f

  10. 50 CFR 401.4 - Activities prohibited.

    Science.gov (United States)

    2010-10-01

    ..., DEVELOPMENT AND ENHANCEMENT § 401.4 Activities prohibited. Law enforcement, public relations, harvesting, marketing and processing activities, construction of fisherman use facilities, and activities concerned...

  11. Active properties of neuronal dendrites.

    Science.gov (United States)

    Johnston, D; Magee, J C; Colbert, C M; Cristie, B R

    1996-01-01

    Dendrites of neurons in the central nervous system are the principal sites for excitatory synaptic input. Although little is known about their function, two disparate perspectives have arisen to describe the activity patterns inherent to these diverse tree-like structures. Dendrites are thus considered either passive or active in their role in integrating synaptic inputs. This review follows the history of dendritic research from before the turn of the century to the present, with a primary focus on the hippocampus. A number of recent techniques, including high-speed fluorescence imaging and dendritic patch clamping, have provided new information and perspectives about the active properties of dendrites. The results support previous notions about the dendritic propagation of action potentials and also indicate which types of voltage-gated sodium and calcium channels are expressed and functionally active in dendrites. Possible roles for the active properties of dendrites in synaptic plasticity and integration are also discussed.

  12. Crystal activation experiment MA-151

    Science.gov (United States)

    Trombka, J. I.; Eller, E. L.; Schmadebeck, R. L.; Dyer, C. S.; Reedy, R. C.; Barr, D. W.; Gilmore, J. S.; Prestwood, R. J.; Bayhurst, B. P.; Perry, D. G.

    1976-01-01

    The crystal activation experiment consisted of two sample packages that were flown in the command module and returned to earth for analysis of the radioactivity induced in them during the flight. The objective of the experiment was to define the background caused by detector activation that interferes when gamma radiation is measured in the 0.02- to 10-megaelectronvolt range from earth orbit. Preliminary results show that the activation of the NaI(Tl) crystal was a factor of 3 below that from a similar measurement on Apollo 17. The identification of certain species and the level of activation observed show an important contribution from the interactions of thermal and energetic neutrons produced as secondaries in the spacecraft. That the activation was reduced by only a factor of 3 compared with the Apollo 17 experiment, despite the geomagnetically shielded orbit, possibly indicates more efficient secondary neutron production by the more energetic cosmic rays.

  13. Advances on Active Tectonics Research

    Institute of Scientific and Technical Information of China (English)

    Chen Yong; Chen Qifu; Li Juan

    2001-01-01

    The tectonic movement at human scale has not been fully understood yet, especially for active tectonics, although it is the basis to study natural hazards and environmental variations. Many national and international scientific plans related closely to active tectonics research have been made in the past ten years. This paper briefly summarized the background of the undertaking of active tectonics research, its advances and existing problems, and the key points in its future studies are also pointed out. The emerging of new technologies like the Earth Observing Sys tem, Digital Seismology and so on provides unusual opportunities for tectonic research. It is emphasized, however, that careful analyses and building up of new theoretical frame are sill the key problems for studies of active tectonics, especially for active tectonics in China' s conti nent.

  14. Antioxidant activity of Citrus fruits.

    Science.gov (United States)

    Zou, Zhuo; Xi, Wanpeng; Hu, Yan; Nie, Chao; Zhou, Zhiqin

    2016-04-01

    Citrus is well-known for its nutrition and health-promotion values. This reputation is derived from the studies on the biological functions of phytochemicals in Citrus fruits and their derived products in the past decades. In recent years, the antioxidant activity of Citrus fruits and their roles in the prevention and treatment of various human chronic and degenerative diseases have attracted more and more attention. Citrus fruits are suggested to be a good source of dietary antioxidants. To have a better understanding of the mechanism underlying the antioxidant activity of Citrus fruits, we reviewed a study on the antioxidant activity of the phytochemicals in Citrus fruits, introduced methods for antioxidant activity evaluation, discussed the factors which influence the antioxidant activity of Citrus fruits, and summarized the underlying mechanism of action. Some suggestions for future study were also presented.

  15. Active matter, then and now.

    Science.gov (United States)

    Keller, Evelyn Fox

    2016-09-01

    Historically, living was divided from dead, inert matter by its autonomous activity. Today, a number of materials not themselves alive are characterized as having inherent activity, and this activity has become the subject of a hot new field of physics, "Active Matter", or "Soft matter become alive." For active matter scientists, the relation of physics to biology is guaranteed in one direction by the assertion that the cell is a material, and hence its study can be considered a branch of material science, and in the other direction, by the claim that the physical dynamics of this material IS what brings the cell to life, and therefore its study is a proper branch of biology. I will examine these claims in relation to the concerns of nineteenth century scientists on the one hand, and on the other, in relation to future prospects of the division between animate and inanimate.

  16. Human activity recognition and prediction

    CERN Document Server

    2016-01-01

    This book provides a unique view of human activity recognition, especially fine-grained human activity structure learning, human-interaction recognition, RGB-D data based action recognition, temporal decomposition, and causality learning in unconstrained human activity videos. The techniques discussed give readers tools that provide a significant improvement over existing methodologies of video content understanding by taking advantage of activity recognition. It links multiple popular research fields in computer vision, machine learning, human-centered computing, human-computer interaction, image classification, and pattern recognition. In addition, the book includes several key chapters covering multiple emerging topics in the field. Contributed by top experts and practitioners, the chapters present key topics from different angles and blend both methodology and application, composing a solid overview of the human activity recognition techniques. .

  17. Antiprotozoal activity of Senna racemosa.

    Science.gov (United States)

    Moo-Puc, Rosa E; Mena-Rejon, Gonzalo J; Quijano, Leovigildo; Cedillo-Rivera, Roberto

    2007-06-13

    Methanol extracts of leaves, roots and bark of Senna racemosa (Mill.) H.S. Irwin & Barneby (syn. Cassia racemosa Mill.) were tested for antiprotozooal activity against Giardia intestinalis and Entamoeba histolytica. All of the tested extracts showed good activity against both protozoa species. Extracts from stem bark and leaves were most active, with an IC(50) of 2.10 microg/mL for Giardia intestinalis and 3.87 microg/mL for Entamoeba histolytica. Of the previously isolated compounds from Senna racemosa, the piperidine alkaloid cassine had greater activity against Giardia intestinalis with an IC(50) of 3.28 microg/mL and chrysophanol, a 1,8-dihydroxy-anthraquinone, was the most active agent against Entamoeba histolytica, with an IC(50) of 6.21 microg/mL.

  18. Improved Active Vibration Isolation Systems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The control force, feedback gain, and actuator stroke of several active vibration isolation systems were analyzed based on a single-layer active vibration isolation system. The analysis shows that the feedback gain and actuator stroke cannot be selected independently and the active isolation system design must make a compromise between the feedback gain and actuator stroke. The performance of active isolation systems can be improved by the joint vibration reduction using an active vibration isolation system with an adaptive dynamic vibration absorber. The results show that the joint vibration reduction method can successfully avoid the compromise between the feedback gain and actuator stroke. The control force and the object vibration amplitude are also greatly reduced.

  19. Berberine acutely activates the glucose transport activity of GLUT1.

    Science.gov (United States)

    Cok, Alexandra; Plaisier, Christina; Salie, Matthew J; Oram, Daniel S; Chenge, Jude; Louters, Larry L

    2011-07-01

    Berberine, which has a long history of use in Chinese medicine, has recently been shown to have efficacy in the treatment of diabetes. While the hypoglycemic effect of berberine has been clearly documented in animal and cell line models, such as 3T3-L1 adipocytes and L6 myotube cells, the mechanism of action appears complex with data implicating activation of the insulin signaling pathway as well as activation of the exercise or AMP kinase-mediated pathway. There have been no reports of the acute affects of berberine on the transport activity of the insulin-insensitive glucose transporter, GLUT1. Therefore, we examined the acute effects of berberine on glucose uptake in L929 fibroblast cells, a cell line that express only GLUT1. Berberine- activated glucose uptake reaching maximum stimulation of five-fold at >40 μM. Significant activation (P berberine effect was not additive to the maximal stimulation by other known stimulants, azide, methylene blue or glucose deprivation, suggesting shared steps between berberine and these stimulants. Berberine significantly reduced the K(m) of glucose uptake from 6.7 ± 1.9 mM to 0.55 ± 0.08 mM, but had no effect on the V(max) of uptake. Compound C, an inhibitor of AMP kinase, did not affect berberine-stimulated glucose uptake, but inhibitors of downstream kinases partially blocked berberine stimulation. SB203580 (inhibitor of p38 MAP kinase) did not affect submaximal berberine activation, but did lower maximal berberine stimulation by 26%, while PD98059 (inhibitor of ERK kinase) completely blocked submaximal berberine activation and decreased the maximal stimulation by 55%. It appears from this study that a portion of the hypoglycemic effects of berberine can be attributed to its acute activation of the transport activity of GLUT1.

  20. Activated and non-activated dephasing in a spin bath

    Science.gov (United States)

    Torrontegui, E.; Kosloff, R.

    2016-09-01

    We analyze different decoherence processes in a system coupled to a bath. Apart from the well known standard dephasing mechanism which is temperature dependent an alternative mechanism is presented, the spin-swap dephasing which does not need initial bath activation and is temperature independent. We show that for dipole interaction in the weak coupling regime the separation of time scales between system and bath can not produce pure dephasing, the process being accompanied by dissipation. Activated and non-activated dephasing processes are analyzed in a diamond nitrogen-vacancy center.

  1. Separating proteins with activated carbon.

    Science.gov (United States)

    Stone, Matthew T; Kozlov, Mikhail

    2014-07-15

    Activated carbon is applied to separate proteins based on differences in their size and effective charge. Three guidelines are suggested for the efficient separation of proteins with activated carbon. (1) Activated carbon can be used to efficiently remove smaller proteinaceous impurities from larger proteins. (2) Smaller proteinaceous impurities are most efficiently removed at a solution pH close to the impurity's isoelectric point, where they have a minimal effective charge. (3) The most efficient recovery of a small protein from activated carbon occurs at a solution pH further away from the protein's isoelectric point, where it is strongly charged. Studies measuring the binding capacities of individual polymers and proteins were used to develop these three guidelines, and they were then applied to the separation of several different protein mixtures. The ability of activated carbon to separate proteins was demonstrated to be broadly applicable with three different types of activated carbon by both static treatment and by flowing through a packed column of activated carbon.

  2. Energy Balance and Physical Activity

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The prevalence of obesity is increasing in most parts of theworld and becoming one of the major global public health problems. Although the components of energy balance have not been adequately estimated over time, available evidence suggests that the increase in obesity is the result of reduced physical activity. Increases in physical activity have been shown to be strongly associated with improving physical fitness and body composition, with probably a positive effect on resting metabolic rate. The Surgeon General's Report on Physical Activity and Health advocates that 30 min of regular, moderate-intensity physical activity is associated with decreases in the risk of chronic diseases and may contribute to quality of life. However, the small changes that contribute 10 min for 3 times a day for aerobic training, or one set instead of three sets of repetitions on resistance training will provide individuals with health benefits. Indeed, nutrition and physical activity should be considered an integral part of fitness and good health, and should be encouraged in all age groups, particularly early in life. The question is no longer centered around the health benefit of increasing physical activity, but rather creating self awareness and behavior changes in individuals. Hence, effective intervention programs are needed that foster long term changes in physical activity. Among various interventions, the Nutrifit program was recently conducted in Thailand and found to improve health related fitness in children. The development of more effective interventions and approaches is a major challenge in this field today.

  3. Antimicrobial activities of squalamine mimics.

    Science.gov (United States)

    Kikuchi, K; Bernard, E M; Sadownik, A; Regen, S L; Armstrong, D

    1997-07-01

    We investigated the antimicrobial properties of compounds with structural features that were designed to mimic those of squalamine, an antibiotic isolated from the stomach of the dogfish shark. The mimics, like squalamine, are sterol-polyamine conjugates. Unlike squalamine, the mimics were simple to prepare, at high yield, from readily available starting materials. Several squalamine mimics showed activity against gram-negative rods, gram-positive cocci including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and fungi. Some had little or no hemolytic activity. The hydrophobicity of the sterol backbone and the length and the cationic charge of the side chains appeared to be critical determinants of activity. One of the squalamine mimics, SM-7, was bactericidal against Escherichia coli, Pseudomonas aeruginosa, and S. aureus; its activity was decreased by divalent or monovalent cations and by bovine serum albumin. Subinhibitory concentrations of SM-7 markedly enhanced the antimicrobial activity of rifampin against gram-negative rods. These results suggest that the compounds may disrupt an outer membrane of gram-negative rods. Squalamine mimics are a new class of broad-spectrum antimicrobial agents. The antagonism of their activity by serum and albumin and their hemolytic properties may limit their use as systemic agents. The squalamine mimics, because of their potencies, broad spectra of antimicrobial activity, and potential for systemic toxicity, appear to be good candidates for development as topical antimicrobial agents.

  4. Sry is a transcriptional activator.

    Science.gov (United States)

    Dubin, R A; Ostrer, H

    1994-09-01

    The SRY gene functions as a genetic switch in gonadal ridge initiating testis determination. The mouse Sry and human SRY open reading frames (ORFs) share a conserved DNA-binding domain (the HMG-box) yet exhibit no additional homology outside this region. As judged by the accumulation of lacZ-SRY hybrid proteins in the nucleus, both the human and mouse SRY ORFs contain a nuclear localization signal. The mouse Sry HMG-box domain selectively binds the sequence NACAAT in vitro when challenged with a random pool of oligonucleotides and binds AACAAT with the highest affinity. When put under the control of a heterologous promotor, the mouse Sry gene activated transcription of a reporter gene containing multiple copies of the AACAAT binding site. Activation was likewise observed for a GAL4-responsive reporter gene, when the mouse Sry gene was linked to the DNA-binding domain of GAL4. Using this system, the activation function was mapped to a glutamine/histidine-rich domain. In addition, LexA-mouse Sry fusion genes activated a LexA-responsive reporter gene in yeast. In contrast, a GAL4-human SRY fusion gene did not cause transcriptional activation. These studies suggest that both the human and the mouse SRY ORFs encode nuclear, DNA-binding proteins and that the mouse Sry ORF can function as a transcriptional activator with separable DNA-binding and activator domains.

  5. Activity Cycle of Solar Filaments

    Indian Academy of Sciences (India)

    K. J. Li; Q. X. Li; P. X. Gao; J. Mu; H. D. Chen; T. W. Su

    2007-06-01

    Long-term variation in the distribution of the solar filaments observed at the Observatorie de Paris, Section de Meudon from March 1919 to December 1989 is presented to compare with sunspot cycle and to study the periodicity in the filament activity, namely the periods of the coronal activity with the Morlet wavelet used. It is inferred that the activity cycle of solar filaments should have the same cycle length as sunspot cycle, but the cycle behavior of solar filaments is globally similar in profile with, but different in detail from, that of sunspot cycles. The amplitude of solar magnetic activity should not keep in phase with the complexity of solar magnetic activity. The possible periods in the filament activity are about 10.44 and 19.20 years. The wavelet local power spectrum of the period 10.44 years is statistically significant during the whole consideration time. The wavelet local power spectrum of the period 19.20 years is under the 95% confidence spectrum during the whole consideration time, but over the mean red-noise spectrum of = 0.72 before approximate Carrington rotation number 1500, and after that the filament activity does not statistically show the period. Wavelet reconstruction indicates that the early data of the filament archive (in and before cycle 16) are more noiseful than the later (in and after cycle 17).

  6. Activation and proteolytic activity of the Treponema pallidum metalloprotease, pallilysin.

    Science.gov (United States)

    Houston, Simon; Hof, Rebecca; Honeyman, Lisa; Hassler, Julia; Cameron, Caroline E

    2012-01-01

    Treponema pallidum is a highly invasive pathogen that undergoes rapid dissemination to establish widespread infection. Previous investigations identified the T. pallidum adhesin, pallilysin, as an HEXXH-containing metalloprotease that undergoes autocatalytic cleavage and degrades laminin and fibrinogen. In the current study we characterized pallilysin's active site, activation requirements, cellular location, and fibrin clot degradation capacity through both in vitro assays and heterologous treponemal expression and degradation studies. Site-directed mutagenesis showed the pallilysin HEXXH motif comprises at least part of the active site, as introduction of three independent mutations (AEXXH [H¹⁹⁸A], HAXXH [E¹⁹⁹A], and HEXXA [H²⁰²A]) abolished pallilysin-mediated fibrinogenolysis but did not adversely affect host component binding. Attainment of full pallilysin proteolytic activity was dependent upon autocatalytic cleavage of an N-terminal pro-domain, a process which could not occur in the HEXXH mutants. Pallilysin was shown to possess a thrombin cleavage site within its N-terminal pro-domain, and in vitro studies confirmed cleavage of pallilysin with thrombin generates a truncated pallilysin fragment that has enhanced proteolytic activity, suggesting pallilysin can also exploit the host coagulation process to facilitate protease activation. Opsonophagocytosis assays performed with viable T. pallidum demonstrated pallilysin is a target of opsonic antibodies, consistent with a host component-interacting, surface-exposed cellular location. Wild-type pallilysin, but not the HEXXA mutant, degraded fibrin clots, and similarly heterologous expression of pallilysin in the non-invasive spirochete Treponema phagedenis facilitated fibrin clot degradation. Collectively these results identify pallilysin as a surface-exposed metalloprotease within T. pallidum that possesses an HEXXH active site motif and requires autocatalytic or host-mediated cleavage of a pro

  7. Physical Activity for a Healthy Weight

    Science.gov (United States)

    ... Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Physical Activity for a Healthy Weight Language: English Español (Spanish) ... calories are used in typical activities? Why is physical activity important? Regular physical activity is important for good ...

  8. Measuring physical activity during pregnancy

    Directory of Open Access Journals (Sweden)

    Teede Helena J

    2011-03-01

    Full Text Available Abstract Background Currently, little is known about physical activity patterns in pregnancy with prior estimates predominantly based on subjective assessment measures that are prone to error. Given the increasing obesity rates and the importance of physical activity in pregnancy, we evaluated the relationship and agreement between subjective and objective physical activity assessment tools to inform researchers and clinicians on optimal assessment of physical activity in pregnancy. Methods 48 pregnant women between 26-28 weeks gestation were recruited. The Yamax pedometer and Actigraph accelerometer were worn for 5-7 days under free living conditions and thereafter the International Physical Activity Questionnaire (IPAQ was completed. IPAQ and pedometer estimates of activity were compared to the more robust and accurate accelerometer data. Results Of 48 women recruited, 30 women completed the study (mean age: 33.6 ± 4.7 years; mean BMI: 31.2 ± 5.1 kg/m2 and 18 were excluded (failure to wear [n = 8] and incomplete data [n = 10]. The accelerometer and pedometer correlated significantly on estimation of daily steps (ρ = 0.69, p -1 day-1 were not significantly correlated and there was poor absolute agreement. Relative to the accelerometer, the IPAQ under predicted daily total METs (105.76 ± 259.13 min-1 day-1 and light METs (255.55 ± 128.41 min-1 day-1 and over predicted moderate METs (-112.25 ± 166.41 min-1 day-1. Conclusion Compared with the accelerometer, the pedometer appears to provide a reliable estimate of physical activity in pregnancy, whereas the subjective IPAQ measure performed less accurately in this setting. Future research measuring activity in pregnancy should optimally encompass objective measures of physical activity. Trial Registration Australian New Zealand Clinical Trial Registry Number: ACTRN12608000233325. Registered 7/5/2008.

  9. Commercial Product Activation Using RFID

    Science.gov (United States)

    Jedrey, Thomas

    2008-01-01

    Radio-frequency identification (RFID) would be used for commercial product activation, according to a proposal. What is new here is the concept of combining RFID with activation - more specifically, using RFID for activating commercial products (principally, electronic ones) and for performing such ancillary functions as tracking individual product units on production lines, tracking shipments, and updating inventories. According to the proposal, an RFID chip would be embedded in each product. The information encoded in the chip would include a unique number for identifying the product. An RFID reader at the point of sale would record the number of the product and would write digital information to the RFID chip for either immediate activation of the product or for later interrogation and processing. To be practical, an RFID product-activation system should satisfy a number of key requirements: the system should be designed to be integrable into the inventory-tracking and the data-processing and -communication infrastructures of businesses along the entire supply chain from manufacture to retail; the system should be resistant to sophisticated hacking; activation codes should be made sufficiently complexity to minimize the probability of activating stolen products; RFID activation equipment at points of sale must be capable to two-way RF communication for the purposes of reading information from, and writing information to, embedded RFID chips; the equipment at points of sale should be easily operable by sales clerks with little or no training; the point-of-sale equipment should verify activation and provide visible and/or audible signals indicating verification or lack thereof; and, the system should be able to handle millions of products per year with minimal human intervention, among other requirements.

  10. Enzymatic activity of myccorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Roman Pachlewski

    2014-11-01

    Full Text Available The investigations included assays of enzymatic activity of ectomycorrhizal fungi from the genera: Amanita, Cenococcum, Coltricia, Hebeloma, Lactarius, Rhizopogon, Russula, Suillus, Tricholoma and the pine ectendomycorrhizal strain MrgX. Among the 22 investigated strains of fungi 18 could decompose starch, 14 urea, 11 asparagine, 7 protein, 6 pectin and 3 ce1lulose. The most varied enzyme activities were found in Amanita muscaria, A. verna, Hebeloma, mesophaeum, ectendomycorrhizal isolate MrgX, Rhizopogon luteolus and Suillus bovinus, the highest cellolotytic activity was shown by the ectendomycorrhizal strain.

  11. Simultaneous tracking and activity recognition

    DEFF Research Database (Denmark)

    Manfredotti, Cristina Elena; Fleet, David J.; Hamilton, Howard J.

    2011-01-01

    Many tracking problems involve several distinct objects interacting with each other. We develop a framework that takes into account interactions between objects allowing the recognition of complex activities. In contrast to classic approaches that consider distinct phases of tracking and activity...... be used to improve the prediction step of the tracking, while, at the same time, tracking information can be used for online activity recognition. Experimental results in two different settings show that our approach 1) decreases the error rate and improves the identity maintenance of the positional...

  12. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  13. FRAUDULENT ACTIVITIES USING VIRTUAL MEETINGS

    Directory of Open Access Journals (Sweden)

    Anne James

    2013-05-01

    Full Text Available This paper investigates fraudulent and illegal activities that take place through virtual meeting systems. The first section gives an introduction to the problem. Section two describes some cases of fraudulent activity using virtual meeting systems. Section three explores some means of capturing such fraudulent activities so thatcriminals can be brought to justice. Section four provides a solution for capturing virtual meeting conversations in a way that could be admissible in court. Section five discusses tell-tale signs that indicates that a conversation maybe fraudulent. Section six discusses Artificial Intelligence (AI techniques that might be used to detectvirtual meeting crime. Section seven discusses the conclusion to the paper.

  14. The Leadership Challenge Activities Book

    CERN Document Server

    Kouzes, James M; Biech, Elaine

    2010-01-01

    ACTIVE Learning for Exemplary Leaders. The best leaders are the best learners. This evidence-based truth has been a foundational principle of The Leadership Challenge since it was first published nearly twenty-five years ago. In this new work, bestselling Leadership Challenge authors Jim Kouzes and Barry Posner team up with experiential learning expert Elaine Biech to bring today's leaders over 100 engaging activities designed to expand and accelerate their leadership development efforts. Grounded in The Five Practices of Exemplary Leadership® model, The Leadership Challenge Activities Book in

  15. Stresslets induced by active swimmers

    CERN Document Server

    Lauga, Eric

    2016-01-01

    Active particles disturb the fluid around them as force dipoles, or stresslets, which govern their collective dynamics. Unlike swimming speeds, the stresslets of active particles are rarely determined due to the lack of a suitable theoretical framework for arbitrary geometry. We propose a general method, based on the reciprocal theorem of Stokes flows, to compute stresslets as integrals of the velocities on the particle's surface, which we illustrate for spheroidal chemically-active particles. Our method will allow tuning the stresslet of artificial swimmers and tailoring their collective motion in complex environments.

  16. Organelle morphogenesis by active remodeling

    CERN Document Server

    Ramakrishnan, N; Rao, Madan; Kumar, P B Sunil

    2014-01-01

    Intracellular organelles are subject to a steady flux of lipids and proteins through active, energy consuming transport processes. Active fission and fusion are promoted by GTPases, e.g., Arf-Coatamer and the Rab-Snare complexes, which both sense and generate local membrane curvature. Here we investigate through Dynamical Triangulation Monte Carlo simulations, the role that these active processes play in determining the morphology and compositional segregation in closed membranes. Our results suggest that the ramified morphologies of organelles observed in-vivo are a consequence of driven nonequilibrium processes rather than equilibrium forces.

  17. Activated protein C modulates the proinflammatory activity of dendritic cells

    Directory of Open Access Journals (Sweden)

    Matsumoto T

    2015-05-01

    Full Text Available Takahiro Matsumoto,1,2* Yuki Matsushima,1* Masaaki Toda,1 Ziaurahman Roeen,1 Corina N D'Alessandro-Gabazza,1,5 Josephine A Hinneh,1 Etsuko Harada,1,3 Taro Yasuma,4 Yutaka Yano,4 Masahito Urawa,1,5 Tetsu Kobayashi,5 Osamu Taguchi,5 Esteban C Gabazza1 1Department of Immunology, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, 2BONAC Corporation, BIO Factory 4F, Fukuoka, 3Iwade Research Institute of Mycology, 4Department of Endocrinology, Diabetes and Metabolism, 5Department of Pulmonary and Critical Care Medicine, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, Japan *These authors contributed equally to this work Background: Previous studies have demonstrated the beneficial activity of activated protein C in allergic diseases including bronchial asthma and rhinitis. However, the exact mechanism of action of activated protein C in allergies is unclear. In this study, we hypothesized that pharmacological doses of activated protein C can modulate allergic inflammation by inhibiting dendritic cells. Materials and methods: Dendritic cells were prepared using murine bone marrow progenitor cells and human peripheral monocytes. Bronchial asthma was induced in mice that received intratracheal instillation of ovalbumin-pulsed dendritic cells. Results: Activated protein C significantly increased the differentiation of tolerogenic plasmacytoid dendritic cells and the secretion of type I interferons, but it significantly reduced lipopolysaccharide-mediated maturation and the secretion of inflammatory cytokines in myeloid dendritic cells. Activated protein C also inhibited maturation and the secretion of inflammatory cytokines in monocyte-derived dendritic cells. Activated protein C-treated dendritic cells were less effective when differentiating naïve CD4 T-cells from Th1 or Th2 cells, and the cellular effect of activated protein C was mediated by its receptors. Mice that received adoptive transfer of activated protein C

  18. Reporting C-14 activities and concentrations

    NARCIS (Netherlands)

    Mook, WG; van der Plicht, J

    1999-01-01

    Three modes of reporting C-14 activities are in use, in part analogous to the internationally accepted (IAEA) conventions for stable isotopes: (1) absolute activity, the specific activity of C-14 or the activity per gram of carbon; (2) activity ratio, the ratio between the absolute activities of a s

  19. Exploring neuronal activity with photons

    Science.gov (United States)

    Bourdieu, Laurent; Léger, Jean-François

    2015-10-01

    The following sections are included: * Introduction * Information coding * Optical recordings of neuronal activity * Functional organization of the cortex at the level of a cortical column * Microarchitecture of a cortical column * Dynamics of neuronal populations * Outlook * Bibliography

  20. Lobbying Semi-Annual Activity

    Data.gov (United States)

    Montgomery County of Maryland — This dataset contains Registration and Activity Reporting information lobbyists have provided. The dollar figures in the far right columns are the total of expenses...

  1. From Lurker to Active Participant

    NARCIS (Netherlands)

    Sloep, Peter; Kester, Liesbeth

    2009-01-01

    The original publication is available from www.springerlink.com. Sloep, P. B., & Kester, L. (2009). From Lurker to Active Participant. In R. Koper (Ed)., Learning Network Services for Professional Development (pp. 17-26). Berlin, Germany: Springer Verlag.

  2. Student-Centered Reading Activities.

    Science.gov (United States)

    Moffett, James; Wagner, Betty Jane

    1991-01-01

    Offers student-centered reading activities designed to bring students to reading maturity and involvement in literature. Discusses partner reading, dramatizing and performing texts, transforming texts, journal writing, discussion, and writing. (PRA)

  3. Physical activity - preventive medicine (image)

    Science.gov (United States)

    Physical activity contributes to health by reducing the heart rate, decreasing the risk for cardiovascular disease, and reducing the amount of bone loss that is associated with age and osteoporosis. Physical ...

  4. Active vs. inactive muscle (image)

    Science.gov (United States)

    ... may lose 20 to 40 percent of their muscle -- and, along with it, their strength -- as they ... have found that a major reason people lose muscle is because they stop doing everyday activities that ...

  5. Be active – eat well

    CERN Multimedia

    2009-01-01

    The campaign was held from 25 to 29 May 2009, and was organised by the Medical Service jointly with the Restaurants Supervisory Committee, CERN Management, the Staff Association and CHIS, with the active support of CERN restaurants.

  6. Active spectral imaging and mapping

    Science.gov (United States)

    Steinvall, Ove

    2014-04-01

    Active imaging and mapping using lasers as illumination sources have been of increasing interest during the last decades. Applications range from defense and security, remote sensing, medicine, robotics, and others. So far, these laser systems have mostly been based on a fix wavelength laser. Recent advances in lasers enable emission of tunable, multiline, or broadband emission, which together with the development of array detectors will extend the capabilities of active imaging and mapping. This paper will review some of the recent work on active imaging mainly for defense and security and remote sensing applications. A short survey of basic lidar relations and present fix wavelength laser systems is followed by a review of the benefits of adding the spectral dimension to active and/or passive electro-optical systems.

  7. Antileishmanial activity of lapachol analogues

    Directory of Open Access Journals (Sweden)

    Nadja MF Lima

    2004-11-01

    Full Text Available The antileishmanial activity of lapachol, isolapachol, and dihydrolapachol, along with soluble derivatives (potassium salt and acetate was obtained. All the compounds were assayed against metacyclic promastigotes of two different species of Leishmania associated to tegumentar leishmaniasis: L. amazonensis and L. braziliensis. All compounds presented significant activity, being isolapachol acetate the most active against promastigotes, with IC50/24h = 1.6 ± 0.0 µg/ml and 3.4 ± 0.5 µg/ml for, respectively, L. amazonensis and L. braziliensis. This compound was also assayed in vivo against L. amazonensis and showed to be active. Its toxicity in vitro was also established, and at concentration similar to the IC50, no toxicity was evidenced. In all experiments, pentamidine isethionate was used as a reference drug. The present results reinforce the potential use of substituted hydroxyquinones and derivatives as promising antileishmanial drugs and suggest a continuing study within this class of compounds.

  8. Nonisothermal activation: nonlinear transport theory

    NARCIS (Netherlands)

    Dekker, H.; Maassen van den Brink, A.

    1998-01-01

    We present the statistical mechanical foundation of nonisothermal stochastic processes, thereby generalizing Kramers' Fokker-Planck model for thermal activation and providing a microscopic context for Rolf Landauer's original ideas on state-dependent diffusion. By applying projection operator method

  9. Sustainability of natural movement activity

    Directory of Open Access Journals (Sweden)

    Matthew Metzgar

    2012-08-01

    Full Text Available In recent years, there has been a focus on reducing energy consumption in commercial buildings as a means of increasing their sustainability. As part of this trend, various health clubs and fitness centers have been designed to lower consumption of resources such as electricity and water. However, energy consumption is just one part of sustainability, with human health and economic health also paramount. When all components of sustainability are analyzed, other forms of physical activity may possess higher levels of sustainability than traditional gym exercise. Natural movement activity consists of outdoor activity that replicates movements performed by ancient humans during the Paleolithic era. A full analysis of sustainability shows that natural movement activity consumes fewer resources and provides unique psychological and physical benefits compared with traditional indoor exercise.

  10. 2012 Robotics Activities at JPL

    Science.gov (United States)

    Volpe, Richard

    2012-01-01

    The Robotics Section of the Jet Propulsion Laboratory (JPL), California Institute of Technology, is engaged in a full spectrum of flight project and research activities. This paper will provide an overview of these efforts, and discuss the recent accomplishments and future directions of them. Specific activities will be high- lighted based on their level of accomplishment, impact on the community, maturity, or novelty. Robotics activities on flight projects are a significant subset of the full effort for these large missions. Complementing flight activities is a diverse set of research efforts for NASA and other U.S. Government agencies. Future directions will be motivated by NASA and other sponsor objectives, as well as success experienced in these current endeavours.

  11. Response to work activity guidance

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This memorandum is concerning the request from the FY95 Platte-Kansas Rivers Ecosystem Work Activity Guidance for refuge managers to review the purposes of refuges...

  12. Active Learning with Multiple Views

    CERN Document Server

    Knoblock, C A; Muslea, I; 10.1613/jair.2005

    2011-01-01

    Active learners alleviate the burden of labeling large amounts of data by detecting and asking the user to label only the most informative examples in the domain. We focus here on active learning for multi-view domains, in which there are several disjoint subsets of features (views), each of which is sufficient to learn the target concept. In this paper we make several contributions. First, we introduce Co-Testing, which is the first approach to multi-view active learning. Second, we extend the multi-view learning framework by also exploiting weak views, which are adequate only for learning a concept that is more general/specific than the target concept. Finally, we empirically show that Co-Testing outperforms existing active learners on a variety of real world domains such as wrapper induction, Web page classification, advertisement removal, and discourse tree parsing.

  13. HUD Initiated Activity Cancellation Reports

    Data.gov (United States)

    Department of Housing and Urban Development — This monthly report displays all HOME activities automatically cancelled by IDIS. Effective January 1, 2011, and the beginning of every month thereafter, committed...

  14. Work activities within sustainable development

    Directory of Open Access Journals (Sweden)

    Francisco Duarte

    2015-06-01

    Full Text Available This paper presents the main results of a Franco-Brazilian Research project entitled "Work, Innovation and Development". The aim is to conceptually consider work activity within sustainable development, and to contribute methodologically towards developing strategies for designing sustainable work systems. After a brief description of the factors and the dimensions that have contributed to the creation of ideas on sustainable development, we will put forward two main approaches for understanding work activity within the context of sustainability, these being: the durability of work activity and the development of work activities for sustainable development. Both approaches are presented and examples are given. This is followed by a discussion of the design of sustainable work systems that focuses particularly on the political and technical dimensions of project management.

  15. Autocatalytic activation of influenza hemagglutinin.

    Science.gov (United States)

    Lee, Jeong H; Goulian, Mark; Boder, Eric T

    2006-12-01

    Enveloped viruses contain surface proteins that mediate fusion between the viral and target cell membranes following an activating stimulus. Acidic pH induces the influenza virus fusion protein hemagglutinin (HA) via irreversible refolding of a trimeric conformational state leading to exposure of hydrophobic fusion peptides on each trimer subunit. Herein, we show that cells expressing fowl plague virus HA demonstrate discrete switching behavior with respect to the HA conformational change. Partially activated states do not exist at the scale of the cell, activation of HA leads to aggregation of cell surface trimers, and newly synthesized HA refold spontaneously in the presence of previously activated HA. These observations imply a feedback mechanism involving self-catalyzed refolding of HA and thus suggest a mechanism similar to the autocatalytic refolding and aggregation of prions.

  16. Active Interrogation for Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Swinhoe, Martyn Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dougan, Arden [National Nuclear Security Administration (NNSA), Washington, DC (United States)

    2015-11-05

    The DDA instrument for nuclear safeguards is a fast, non-destructive assay, active neutron interrogation technique using an external 14 MeV DT neutron generator for characterization and verification of spent nuclear fuel assemblies.

  17. Anthelmintic activity of Pongamia glabra

    Directory of Open Access Journals (Sweden)

    R.B. Laware

    2007-05-01

    Full Text Available Leaves, wood, seed, bark and pericarp of the fruit of Pongamia glabra were separately dried, powdered and extracted with methanol in Soxhlet extractor. Anthelmintic activity of these various extracts was evaluatedon Indian adult earthworms, Pherentima posthuma. Results showed that the seed part of P. glabra took less time to cause paralysis and death of the earthworms; therefore, seeds were extracted successively withpetroleum ether, ethyl acetate and methanol in Soxhlet extractor. Again these extracts were screened for anthelmintic activity. Results showed that the ethyl acetate extract of seeds of P. glabra was most potentfollowed by petroleum ether extract. It can be concluded that anthelmintic activity of the seed of P. glabra is due to the active principles present mostly in the ethyl acetate and petroleum ether extracts.

  18. Complement Activation Alters Platelet Function

    Science.gov (United States)

    2015-12-01

    Award Number: W81XWH-12-1-0523 TITLE: Complement Activation Alters Platelet Function PRINCIPAL INVESTIGATOR: George Tsokos, M.D. CONTRACTING...Activation Alters Platelet Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1-0523 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) George Tsokos, M.D...a decreased level of disease. Further studies will expand upon these observations better outlining the function of platelets in the injury associated

  19. Optimal constructions for active diagnosis

    OpenAIRE

    Haar, Stefan; Haddad, Serge; Melliti, Tarek; Schwoon, Stefan

    2017-01-01

    International audience; Diagnosis is the task of detecting fault occurrences in a partially observed system. Depending on the possible observations, a discrete-event system may be diagnosable or not. Active diagnosis aims at controlling the system to render it diagnosable. Past research has proposed solutions for this problem, but their complexity remains to be improved. Here, we solve the decision and synthesis problems for active diagnosability, proving that (1) our procedures are optimal w...

  20. Antioxidant activity of polyaniline nanofibers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Well-confined uniform polyaniline (PANT) nanofibers were synthesized by using photo-assisted chemical oxidative polymerization of aniline in the presence of different dopant acids, and the radical scavenging ability of the produced PANI nanofibers was determined by the DPPH assay. It was found that the antioxidant activity of PANI nanofibers was higher than conventional PANI,and increased with decreasing of averaged diameter of the nanofibers. The enhanced antioxidant activity was concerned with increased surface area of PANI nanofibers.