Abdul Manas, Nor Hasmaliana; Pachelles, Samson; Mahadi, Nor Muhammad; Illias, Rosli Md.
2014-01-01
A maltogenic amylase (MAG1) from alkaliphilic Bacillus lehensis G1 was cloned, expressed in Escherichia coli, purified and characterised for its hydrolysis and transglycosylation properties. The enzyme exhibited high stability at pH values from 7.0 to 10.0. The hydrolysis of β-cyclodextrin (β-CD) produced malto-oligosaccharides of various lengths. In addition to hydrolysis, MAG1 also demonstrated transglycosylation activity for the synthesis of longer malto-oligosaccharides. The thermodynamic equilibrium of the multiple reactions was shifted towards synthesis when the reaction conditions were optimised and the water activity was suppressed, which resulted in a yield of 38% transglycosylation products consisting of malto-oligosaccharides of various lengths. Thin layer chromatography and high-performance liquid chromatography analyses revealed the presence of malto-oligosaccharides with a higher degree of polymerisation than maltoheptaose, which has never been reported for other maltogenic amylases. The addition of organic solvents into the reaction further suppressed the water activity. The increase in the transglycosylation-to-hydrolysis ratio from 1.29 to 2.15 and the increased specificity toward maltopentaose production demonstrated the enhanced synthetic property of the enzyme. The high transglycosylation activity of maltogenic amylase offers a great advantage for synthesising malto-oligosaccharides and rare carbohydrates. PMID:25221964
Introducing transgalactosylation activity into a family 42 β-galactosidase.
Strazzulli, Andrea; Cobucci-Ponzano, Beatrice; Carillo, Sara; Bedini, Emiliano; Corsaro, Maria Michela; Pocsfalvi, Gabriella; Withers, Stephen G; Rossi, Mosè; Moracci, Marco
2017-05-01
Chemo-enzymatic synthesis of oligosaccharides exploits the diversity of glycosidases and their ability to promote transglycosylation reactions in parallel with hydrolysis. Methods to increase the transglycosylation/hydrolysis ratio include site-directed mutagenesis and medium modification. The former approach was successful in several cases and has provided the best synthetic yields with glycosynthases-mutants at the catalytic nucleophile position that promote transglycosylation with high efficiency, but do not hydrolyze the oligosaccharide products. Several glycosidases have proven recalcitrant to this conversion, thus alternative methods to increase the transglycosylation/hydrolysis ratio by mutation would be very useful. Here we show that a mutant of a β-galactosidase from Alicyclobacillus acidocaldarius in an invariant residue in the active site of the enzymes of this family (glutamic acid 361) carries out efficient transglycosylation reactions on different acceptors only in the presence of external ions with yields up to 177-fold higher than that of the wild type. This is the first case in which sodium azide and sodium formate in combination with site-directed mutagenesis have been used to introduce transglycosylation activity into a glycosidase. These observations will hopefully guide further efforts to generate useful synthases. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Fan, Shu-Quan; Huang, Wei; Wang, Lai-Xi
2012-01-01
Endo-β-N-acetylglucosaminidase from Streptococcus pneumoniae (Endo-D) is an endoglycosidase capable of hydrolyzing the Fc N-glycan of intact IgG antibodies after sequential removal of the sialic acid, galactose, and internal GlcNAc residues in the N-glycan. Endo-D also possesses transglycosylation activity with sugar oxazoline as the donor substrate, but the transglycosylation yield is low due to enzymatic hydrolysis of the donor substrate and the product. We report here our study on the hydrolytic and transglycosylation activity of recombinant Endo-D and its selected mutants. We found that Endo-D preferred core-fucosylated N-glycan for hydrolysis but favored nonfucosylated GlcNAc acceptor for transglycosylation. Several mutants showed significantly enhanced transglycosylation efficiency over the wild type enzyme. Two mutants (N322Q and N322A) were identified as typical glycosynthases that demonstrated remarkable transglycosylation activity with only marginal or no product hydrolysis activity. Kinetic studies revealed that the N332Q and N322A glycosynthases had much higher catalytic efficiency for glycosylating the nonfucosylated GlcNAc acceptor. In comparison, the N322Q was much more efficient than N322A for transglycosylation. However, N332Q and N332A could not take more complex N-glycan oxazoline as substrate for transglycosylation, indicating their strict substrate specificity. The usefulness of the N332Q glycosynthase was exemplified by its application for efficient glycosylation remodeling of IgG-Fc domain. PMID:22318728
McDougall, Gordon J; Ross, Heather A; Swanston, J Stuart; Davies, Howard V
2004-02-01
Limit dextrinase (EC 3.2.1.41) from germinating barley (Hordeum vulgare L) can be activated by millimolar concentrations of linear maltodextrins with a degree of polymerisation > or = 2. The activation was assay-dependent; it was detected using assays based on the solubilisation of cross-linked dyed pullulan but not in assays that directly measured cleavage events such as the formation of new reducing termini. This strongly suggested that maltodextrins did not increase the catalytic rate of limit dextrinase i.e. this is not a true activation. On the other hand, considerable activation was noted in assays that measured pullulan degradation by reduction in viscosity. Taken together, this suggested that maltodextrins altered the mode of action of limit dextrinase, causing more rapid decreases in viscosity or greater solubilisation of dye-linked pullulan fragments per cleavage event. The proposed mechanism of activation by alteration in action pattern was reminiscent of initial work in the discovery of xyloglucan endotransglycosylase. Therefore, the ability of limit dextrinase to catalyse transglycosylation reactions into pullulan was tested and confirmed by an assay based on the incorporation of a fluorescently labelled maltotriose derivative into higher-molecular-weight products. The transglycosylation reaction was dependent on limit dextrinase activity and was enhanced in more highly purified preparations of limit dextrinase. Transglycosylation was inhibited by unlabelled maltotriose. How transglycosylation accounts for the apparent activation of limit dextrinase by maltodextrins and the physiological relevance of this novel reaction are discussed.
Shivlata, L; Satyanarayana, T
2017-04-01
Streptomyces badius DB-1 produces α-amylase extracellularly, and its production was enhanced 5.1-fold (from 9.47 ± 0.51 to 48.23 ± 1.45 U mL -1 ) due to optimization by one-variable-at-a-time and statistical approaches. Soluble starch emerged as the most influential factor that strongly affected enzyme production. The purified enzyme is a monomer with a molecular mass of ~57 kDa and optimally active at 50 °C and pH 6.0. The enzyme hydrolyzes soluble as well as raw starches into simpler sugars with a high proportion (>40.0 %) of maltotetraose. It is optimally active at moderate temperature and generates maltooligosaccharides from starch, thus, useful as an antistale in bread making. It also plays a role in increasing the formation of maltooligosaccharides due to transglycosylation activity, thus, finds application in functional foods. This is the first report on the production of raw starch-digesting α-amylase by S. badius with transglycosylation activity.
Zeuner, Birgitte; Jers, Carsten; Mikkelsen, Jørn Dalgaard; Meyer, Anne S
2014-10-08
Recently, significant progress has been made within enzymatic synthesis of biomimetic, functional glycans, including, for example, human milk oligosaccharides. These compounds are mainly composed of N-acetylglucosamine, fucose, sialic acid, galactose, and glucose, and their controlled enzymatic synthesis is a novel field of research in advanced food ingredient chemistry, involving the use of rare enzymes, which have until now mainly been studied for their biochemical significance, not for targeted biosynthesis applications. For the enzymatic synthesis of biofunctional glycans reaction parameter optimization to promote "reverse" catalysis with glycosidases is currently preferred over the use of glycosyl transferases. Numerous methods exist for minimizing the undesirable glycosidase-catalyzed hydrolysis and for improving the trans-glycosylation yields. This review provides an overview of the approaches and data available concerning optimization of enzymatic trans-glycosylation for novel synthesis of complex bioactive carbohydrates using sialidases, α-l-fucosidases, and β-galactosidases as examples. The use of an adequately high acceptor/donor ratio, reaction time control, continuous product removal, enzyme recycling, and/or the use of cosolvents may significantly improve trans-glycosylation and biocatalytic productivity of the enzymatic reactions. Protein engineering is also a promising technique for obtaining high trans-glycosylation yields, and proof-of-concept for reversing sialidase activity to trans-sialidase action has been established. However, the protein engineering route currently requires significant research efforts in each case because the structure-function relationship of the enzymes is presently poorly understood.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kang, Hee-Kwon; Cha, Hyunju; Yang, Tae-Joo
2008-02-01
Di-O-{alpha}-maltosyl-{beta}-cyclodextrin ((G2){sub 2}-{beta}-CD) was synthesized from 6-O-{alpha}-maltosyl-{beta}-cyclodextrin (G2-{beta}-CD) via a transglycosylation reaction catalyzed by TreX, a debranching enzyme from Sulfolobus solfataricus P2. TreX showed no activity toward glucosyl-{beta}-CD, but a transfer product (1) was detected when the enzyme was incubated with maltosyl-{beta}-CD, indicating specificity for a branched glucosyl chain bigger than DP2. Analysis of the structure of the transfer product (1) using MALDI-TOF/MS and isoamylase or glucoamylase treatment revealed it to be dimaltosyl-{beta}-CD, suggesting that TreX transferred the maltosyl residue of a G2-{beta}-CD to another molecule of G2-{beta}-CD by forming an {alpha}-1,6-glucosidic linkage. When [{sup 14}C]-maltose and maltosyl-{beta}-CD were reactedmore » with the enzyme, the radiogram showed no labeled dimaltosyl-{beta}-CD; no condensation product between the two substrates was detected, indicating that the synthesis of dimaltosyl-{beta}-CD occurred exclusively via transglycosylation of an {alpha}-1,6-glucosidic linkage. Based on the HPLC elution profile, the transfer product (1) was identified to be isomers of 6{sup 1},6{sup 3}- and 6{sup 1},6{sup 4}-dimaltosyl-{beta}-CD. Inhibition studies with {beta}-CD on the transglycosylation activity revealed that {beta}-CD was a mixed-type inhibitor, with a K{sub i} value of 55.6 {mu}mol/mL. Thus, dimaltosyl-{beta}-CD can be more efficiently synthesized by a transglycosylation reaction with TreX in the absence of {beta}-CD. Our findings suggest that the high yield of (G2){sub 2}-{beta}-CD from G2-{beta}-CD was based on both the transglycosylation action mode and elimination of the inhibitory effect of {beta}-CD.« less
Go, Young-Hoon; Kim, Tae-Kwon; Lee, Kwang-Woo; Lee, Yong-Hyun
2007-09-01
The functional characteristics of a beta-cyclodextrin glucanotransferase (CGTase) excreted from alkalophilic Bacillus sp. BL-31 that is highly specific for the intermolecular transglycosylation of bioflavonoids were investigated. The new beta-CGTase showed high specificities for glycosyl acceptor bioflavonoids, including naringin, rutin, and hesperidin, and especially naringin. The transglycosylation of naringin into glycosyl naringin was then carried out under the conditions of 80 units of CGTase per gram of maltodextrin, 5 g/l of naringin, 25 g/l of maltodextrin, and 1 mM Mn2+ ion at 40 degrees C for 6 h, resulting in a high conversion yield of 92.1%.
Li, Sha; Li, Wei; Xiao, Qiu-yan; Xia, Yongmei
2013-06-01
Stevioside is an abundant sweetener extracted from Stevia rebaudiana leaf with a bitter aftertaste. Enzymatic transglycosylation of stevioside is a solution to improve the edulcorant quality of stevioside, but highly derivatised stevioside coming with high conversion of stevioside is undesired. In this experiment, the transglycosylation of stevioside was investigated by using a commercial cyclodextrin glucanotransferase and cornstarch hydrolyzate. With controlled parameters, the product was mainly composed of mono- and di-glucosylated stevioside while the highest stevioside conversion reached 77.11%. Neither kinetic nor thermodynamic factor stimulated the formation of high substituted steviosides. The simultaneous hydrolysis in the reaction might inhibit the yield of highly substituted steviosides. Copyright © 2012 Elsevier Ltd. All rights reserved.
Choragudi, Shechinah Felice; Veeramachaneni, Ganesh Kumar; Raman, BV; JS, Bondili
2014-01-01
Endo- β-N-acetylgucosaminidases (ENGases) are the enzymes that catalyze both hydrolysis and transglycosylation reactions. It is of interest to study ENGases because of their ability to synthesize glycopeptides. Homology models of Human, Arabidopsis thaliana and Sorghum ENGases were developed and their active sites marked based on information available from Arthrobacter protophormiae (PDB ID: 3FHQ) ENGase. Further, these models were docked with the natural substrate GlcNAc-Asn and the inhibitor Man3GlcNAc-thiazoline. The catalytic triad of Asn, Glu and Tyr (N171, E173 and Y205 of bacteria) were found to be conserved across the phyla. The crucial Y299F mutation showing 3 times higher transglycosylation activity than in wild type Endo-A is known. The hydrolytic activity remained unchanged in bacteria, while the transglycosylation activity increased. This Y to F change is found to be naturally evolved and should be attributing higher transglycosylation rates in human and Arabidopsis thaliana ENGases. Ligand interactions Ligplots revealed the interaction of amino acids with hydrophobic side chains and polar uncharged side chain amino acids. Thus, structure based molecular model-ligand interactions provide insights into the catalytic mechanism of ENGases and assist in the rational engineering of ENGases. PMID:25258486
Choragudi, Shechinah Felice; Veeramachaneni, Ganesh Kumar; Raman, Bv; Js, Bondili
2014-01-01
Endo- β-N-acetylgucosaminidases (ENGases) are the enzymes that catalyze both hydrolysis and transglycosylation reactions. It is of interest to study ENGases because of their ability to synthesize glycopeptides. Homology models of Human, Arabidopsis thaliana and Sorghum ENGases were developed and their active sites marked based on information available from Arthrobacter protophormiae (PDB ID: 3FHQ) ENGase. Further, these models were docked with the natural substrate GlcNAc-Asn and the inhibitor Man3GlcNAc-thiazoline. The catalytic triad of Asn, Glu and Tyr (N171, E173 and Y205 of bacteria) were found to be conserved across the phyla. The crucial Y299F mutation showing 3 times higher transglycosylation activity than in wild type Endo-A is known. The hydrolytic activity remained unchanged in bacteria, while the transglycosylation activity increased. This Y to F change is found to be naturally evolved and should be attributing higher transglycosylation rates in human and Arabidopsis thaliana ENGases. Ligand interactions Ligplots revealed the interaction of amino acids with hydrophobic side chains and polar uncharged side chain amino acids. Thus, structure based molecular model-ligand interactions provide insights into the catalytic mechanism of ENGases and assist in the rational engineering of ENGases.
Raich, Lluís; Borodkin, Vladimir; Fang, Wenxia; Castro-López, Jorge; van Aalten, Daan M F; Hurtado-Guerrero, Ramón; Rovira, Carme
2016-03-16
The conversion of glycoside hydrolases (GHs) into transglycosylases (TGs), i.e., from enzymes that hydrolyze carbohydrates to enzymes that synthesize them, represents a promising solution for the large-scale synthesis of complex carbohydrates for biotechnological purposes. However, the lack of knowledge about the molecular details of transglycosylation hampers the rational design of TGs. Here we present the first crystallographic structure of a natural glycosyl-enzyme intermediate (GEI) of Saccharomyces cerevisiae Gas2 in complex with an acceptor substrate and demonstrate, by means of quantum mechanics/molecular mechanics metadynamics simulations, that it is tuned for transglycosylation (ΔG(⧧) = 12 kcal/mol). The 2-OH···nucleophile interaction is found to be essential for catalysis: its removal raises the free energy barrier significantly (11 and 16 kcal/mol for glycosylation and transglycosylation, respectively) and alters the conformational itinerary of the substrate (from (4)C1 → [(4)E](⧧) → (1,4)B/(4)E to (4)C1 → [(4)H3](⧧) → (4)C1). Our results suggest that changes in the interactions involving the 2-position could have an impact on the transglycosylation activity of several GHs.
Iwamoto, Mitsuhiro; Sekiguchi, Yukiko; Nakamura, Kensuke; Kawaguchi, Yoshirou; Honda, Takeshi; Hasegawa, Jun
2018-01-01
The fine structures of Fc N-glycan modulate the biological functions and physicochemical properties of antibodies. By remodeling N-glycan to obtain a homogeneous glycoform or chemically modified glycan, antibody characteristics can be controlled or modified. Such remodeling can be achieved by transglycosylation reactions using a mutant of endoglycosidase from Streptococcus pyogenes (Endo-S) and glycan oxazoline. In this study, we generated improved mutants of Endo-S by introducing additional mutations to the D233Q mutant. Notably, Endo-S D233Q/Q303L, D233Q/E350Q, and several other mutations resulted in transglycosylation efficiencies exceeding 90%, with a single-digit donor-to-substrate ratio of five, and D233Q/Y402F/D405A and several other mutations resulted in slightly reduced transglycosylation efficiencies accompanied by no detectable hydrolysis activity for 48 h. We further demonstrated that the combined use of mutants of Endo-S with Endo-M or Endo-CC, endoglycosidases from Mucor hiemalis and Coprinopsis cinerea, enables one-pot transglycosylation from sialoglycopeptide to antibodies. This novel reaction enables glycosylation remodeling of antibodies, without the chemical synthesis of oxazoline in advance or in situ.
Sekiguchi, Yukiko; Nakamura, Kensuke; Kawaguchi, Yoshirou; Honda, Takeshi; Hasegawa, Jun
2018-01-01
The fine structures of Fc N-glycan modulate the biological functions and physicochemical properties of antibodies. By remodeling N-glycan to obtain a homogeneous glycoform or chemically modified glycan, antibody characteristics can be controlled or modified. Such remodeling can be achieved by transglycosylation reactions using a mutant of endoglycosidase from Streptococcus pyogenes (Endo-S) and glycan oxazoline. In this study, we generated improved mutants of Endo-S by introducing additional mutations to the D233Q mutant. Notably, Endo-S D233Q/Q303L, D233Q/E350Q, and several other mutations resulted in transglycosylation efficiencies exceeding 90%, with a single-digit donor-to-substrate ratio of five, and D233Q/Y402F/D405A and several other mutations resulted in slightly reduced transglycosylation efficiencies accompanied by no detectable hydrolysis activity for 48 h. We further demonstrated that the combined use of mutants of Endo-S with Endo-M or Endo-CC, endoglycosidases from Mucor hiemalis and Coprinopsis cinerea, enables one-pot transglycosylation from sialoglycopeptide to antibodies. This novel reaction enables glycosylation remodeling of antibodies, without the chemical synthesis of oxazoline in advance or in situ. PMID:29474426
Inhibitory effect of chondroitin sulfate oligosaccharides on bovine testicular hyaluronidase.
Kakizaki, Ikuko; Koizumi, Hideyo; Chen, Fengchao; Endo, Masahiko
2015-05-05
Hyaluronan and chondroitin sulfates are prominent components of the extracellular matrices of animal tissues; however, their functions in relation to their oligosaccharide structures have not yet been fully elucidated. The oligosaccharides of hyaluronan and chondroitin sulfate were prepared and used to investigate their effects on the hydrolysis and transglycosylation reactions of bovine testicular hyaluronidase when hyaluronan was used as a substrate. Hydrolysis and transglycosylation activities were assessed in independent reaction systems by analyzing the products by HPLC. The hydrolysis and transglycosylation reactions of bovine testicular hyaluronidase were dose-dependently inhibited by chondroitin sulfate oligosaccharides, but not by hyaluronan or chondroitin oligosaccharides. A kinetic analysis of the hydrolysis reaction using hyaluronan octasaccharide revealed that the inhibition mode by chondroitin sulfate oligosaccharides was competitive. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tong, Xin; Li, Tiezheng; Orwenyo, Jared; Toonstra, Christian; Wang, Lai-Xi
2018-04-01
A facile, one-pot enzymatic glycan remodeling of antibody rituximab to produce homogeneous high-mannose and hybrid type antibody glycoforms is described. This method was based on the unique substrate specificity of the endoglycosidase S (Endo-S) from Streptococcus pyogenes. While Endo-S efficiently hydrolyzes the bi-antennary complex type IgG Fc N-glycans, we found that Endo-S did not hydrolyze the "ground state" high-mannose or hybrid glycoforms, and only slowly hydrolyzed the highly activated high-mannose or hybrid N-glycan oxazolines. Moreover, we found that wild-type Endo-S could efficiently use high-mannose or hybrid glycan oxazolines for transglycosylation without product hydrolysis. The combination of the remarkable difference in substrate specificity of Endo-S allows the deglycosylation of heterogeneous rituximab and the transglycosylation with glycan oxazoline to take place in one-pot without the need of isolating the deglycosylated intermediate or changing the enzyme to afford the high-mannose type, hybrid type, and some selectively modified truncated form of antibody glycoforms. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sakaguchi, Kouta; Katoh, Toshihiko; Yamamoto, Kenji
2016-11-01
Glycan conversion of glycoprotein via the transglycosylation activity of endo-β-N-acetylglucosaminidase is a promising chemoenzymatic technology for the production of glycoproteins including bio-medicines with a homogeneous glycoform. Although Endo-M is a key enzyme in this process, its product undergoes rehydrolysis, which leads to a lower yield, and limits the practical application of this enzyme. We developed several Endo-M mutant enzymes including N175Q with glycosynthase-like activity and/or transglycosidase-like activity. We found that the Endo-M N175H mutant showed glycosynthase-like activity comparable to N175Q as well as transglycosidase-like activity superior to N175Q. Using a natural sialylglycopeptide as a donor substrate, N175H readily transferred the sialo-glycan onto an N-acetylglucosamine residue attached to bovine ribonuclease B (RNase B), yielding a nonnative sialoglycosylated RNase B. These results demonstrate that use of Endo-M N175H is an alternative glycoengineering technique, which provides a relatively high yield of transglycosylation product and avoids the laborious synthesis of a sugar oxazoline as a donor substrate. © 2015 International Union of Biochemistry and Molecular Biology, Inc.
Guo, Longcheng; Chen, Xiaodi; Xu, Li; Xiao, Min; Lu, Lili
2018-07-01
Gut bacteria provide a rich source of glycosidases that can recognize and/or hydrolyze glycans for nutrition. Interestingly, some glycosidases have also been found to catalyze transglycosylation reactions in vitro and thus can be used for oligosaccharide synthesis. In this work, six putative and one known exo -α-sialidase genes-three from Bacteroides fragilis NCTC9343, three from Clostridium perfringens ATCC 13124, and one known from Bifidobacterium bifidum JCM1254-were subjected to gene cloning and heterogeneous expression in Escherichia coli The recombinant enzymes were purified, characterized for substrate specificity, and screened for transglycosylation activity. A sialidase, named BfGH33C, from B. fragilis NCTC9343 was found to possess excellent transglycosylation activity for the synthesis of sialylated human milk oligosaccharide. The native BfGH33C was a homodimer with a molecular weight of 113.6 kDa. The K m and k cat values for 4-methylumbelliferyl N -acetyl-α-d-neuraminic acid and sialic acid dimer were determined to be 0.06 mM and 283.2 s -1 , and 0.75 mM and 329.6 s -1 , respectively. The enzyme was able to transfer sialyl from sialic acid dimer or oligomer to lactose with high efficiency and strict α2-6 regioselectivity. The influences of the initial substrate concentration, pH, temperature, and reaction time on transglycosylation were investigated in detail. Using 40 mM sialic acid dimer (or 40 mg/ml oligomer) and 1 M lactose (pH 6.5) at 50°C for 10 min, BfGH33C could specifically produce 6'-sialyllactose, a dominant sialylated human milk oligosaccharide, at a maximal conversion ratio above 20%. It provides a promising alternative to the current chemical and enzymatic methods for obtaining sialylated oligosaccharides. IMPORTANCE Sialylated human milk oligosaccharides are significantly beneficial to the neonate, as they play important roles in supporting resistance to pathogens, gut maturation, immune function, and brain and cognitive development. Therefore, access to the sialylated oligosaccharides has attracted increasing attention both for the study of saccharide functions and for the development of infant formulas that could mimic the nutritional value of human milk. Nevertheless, nine-carbon sialic acids are rather complicated for the traditional chemical modifications, which require multiple protection and deprotection steps to achieve a specific glycosidic bond. Here, the exo -α-sialidase BfGH33C synthesized 6'-sialyllactose in a simple step with high transglycosylation activity and strict regioselectivity. Additionally, it could utilize oligosialic acid, which was newly prepared in an easy, economical way to reduce the substrate cost, as a glycosyl donor. All the studies laid a foundation for the practical use of BfGH33C in large-scale synthesis of sialylated oligosaccharides in the future. Copyright © 2018 American Society for Microbiology.
Wang, Caihong; Zhang, Jiankang; Wang, Yuan; Niu, Canfang; Ma, Rui; Wang, Yaru; Bai, Yingguo; Luo, Huiying; Yao, Bin
2016-04-15
Acidophilic β-mannanases have been attracting much attention due to their excellent activity under extreme acidic conditions and significant industrial applications. In this study, a β-mannanase gene of glycoside hydrolase family 5, man5A, was cloned from Gloeophyllum trabeum CBS900.73, and successfully expressed in Pichia pastoris. Purified recombinant Man5A was acidophilic with a pH optimum of 2.5 and exhibited great pH adaptability and stability (>80% activity over pH 2.0-6.0 and pH 2.0-10.0, respectively). It had a high specific activity (1356 U/mg) against locust bean gum, was able to degrade galactomannan and glucomannan in a classical four-site binding mode, and catalyzed the transglycosylation of mannotetrose to mannooligosaccharides with higher degree of polymerization. Besides, it had great resistance to pepsin and trypsin and digested corn-soybean meal based diet in a comparable way with a commercial β-mannanase under the simulated gastrointestinal conditions of pigs. This acidophilic β-mannanase represents a valuable candidate for wide use in various industries, especially in the feed. Copyright © 2015 Elsevier Ltd. All rights reserved.
Adari, Bhaskar Rao; Alavala, Sateesh; George, Sara A; Meshram, Harshadas M; Tiwari, Ashok K; Sarma, Akella V S
2016-06-01
Rebaudioside-A is the second most abundant sweet diterpene glycoside (1-3%) present in the leaves of Stevia rebaudiana Bertoni, and is now being considered as a possible sucrose substitute due to its pleasant organoleptic properties and associated health benefits. In the present study, a novel in situ enzymatic transglycosylation of stevioside has been developed by pre-treating the stevia leaves with cellulase and adding soluble starch as the glucosyl donor. The results confirm that the transglycosylation of stevioside led to an enrichment in the rebaudioside-A content from 4% to 66%. This was further purified by multiple column chromatography to obtain 95% pure rebaudioside-A. The isolated rebaudioside-A showed concentration-dependent α-glucosidase inhibitory activity with IC50=35.01 μg/ml. Thus the study highlights the biotransformation of stevioside present in stevia leaves to rebaudioside-A by a simple, inexpensive and eco-friendly process that has commercial potential. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kim, Tae-Jip; Kim, Myo-Jeong; Kim, Byung-Cheon; Kim, Jae-Cherl; Cheong, Tae-Kyou; Kim, Jung-Wan; Park, Kwan-Hwa
1999-01-01
A maltogenic amylase gene was cloned in Escherichia coli from a gram-negative thermophilic bacterium, Thermus strain IM6501. The gene encoded an enzyme (ThMA) with a molecular mass of 68 kDa which was expressed by the expression vector p6xHis119. The optimal temperature of ThMA was 60°C, which was higher than those of other maltogenic amylases reported so far. Thermal inactivation kinetic analysis of ThMA indicated that it was stabilized in the presence of 10 mM EDTA. ThMA harbored both hydrolysis and transglycosylation activities. It hydrolyzed β-cyclodextrin and starch mainly to maltose and pullulan to panose. ThMA not only hydrolyzed acarbose, an amylase inhibitor, to glucose and pseudotrisaccharide (PTS) but also transferred PTS to 17 sugar acceptors, including glucose, fructose, maltose, cellobiose, etc. Structural analysis of acarbose transfer products by using methylation, thin-layer chromatography, high-performance ion chromatography, and nuclear magnetic resonance indicated that PTS was transferred primarily to the C-6 of the acceptors and at lower degrees to the C-3 and/or C-4. The transglycosylation of sugar to methyl-α-d-glucopyranoside by forming an α-(1,3)-glycosidic linkage was demonstrated for the first time by using acarbose and ThMA. Kinetic analysis of the acarbose transfer products showed that the C-4 transfer product formed most rapidly but readily hydrolyzed, while the C-6 transfer product was stable and accumulated in the reaction mixture as the main product. PMID:10103262
Letchmanan, Kumaran; Shen, Shou-Cang; Ng, Wai Kiong; Tan, Reginald B H
2018-01-01
Biopharmaceutical properties of poorly water-soluble antimalarial drug, Artemisinin (ART), were improved by formulating amorphous solid dispersions with transglycosylated food additives (Hsp-G and Stevia-G) via co-spray drying. Both the formulated ART/Hsp-G and ART/Stevia-G showed superior dissolution properties with a burst release of more than 95% of drug within 5 min, whereas untreated ART dissolved only 4% in 5min. The supersaturation solubility of the formulated ART was enhanced by 2-fold as compared with untreated counterpart. The storage stability tests indicated that these formulations chemically stable at room temperature and under low humidity (<18% RH) conditions. However, high humidity (75% RH) induced re-crystallization and caused changes in the physical appearance of the solid dispersions. In addition, both the food additives and ART formulated samples showed low cytotoxicity to Caco-2 cell line suggesting their good biocompatibility. Thus, the formation of solid dispersions of ART with transglycosylated food additives is a potentially safe and effective approach to enhance the bioavailability of poorly water-soluble ART. Copyright © 2017 Elsevier B.V. All rights reserved.
Fujimori, Miki; Kadota, Kazunori; Kato, Kouki; Seto, Yoshiki; Onoue, Satomi; Sato, Hideyuki; Ueda, Hiroshi; Tozuka, Yuichi
2016-01-01
The improvement in the solubility and dissolution rate may promote a superior absorption property towards the human body. The spray-dried powders (SDPs) of ipriflavone, which was used as a model hydrophobic flavone, with trans-glycosylated rutin (Rutin-G) showed the highest solubilizing effect of ipriflavone among three types of trans-glycosylated food additives. The SDPs of ipriflavone with Rutin-G have both a significant higher dissolution rate and solubility enhancement of ipriflavone. This spray-dried formulation of ipriflavone with Rutin-G exhibited a low hygroscopicity as a critical factor in product preservation. In addition, an improvement in the oral absorption of ipriflavone was achieved by means of preparing composite particles of ipriflavone/Rutin-G via spray drying, indicating a 4.3-fold increase in the area under the plasma concentration-time curve compared with that of untreated ipriflavone. These phenomena could be applicable to food ingredients involving hydrophobic flavones for producing healthy food with a high quality. Copyright © 2015 Elsevier Ltd. All rights reserved.
Lee, S J; Kim, J C; Kim, M J; Kitaoka, M; Park, C S; Lee, S Y; Ra, M J; Moon, T W; Robyt, J F; Park, K H
1999-09-01
Naringin, a bitter compound in citrus fruits, was transglycosylated by Bacillus stearothermophilus maltogenic amylase reaction with maltotriose to give a series of mono-, di-, and triglycosylnaringins. Glycosylation products of naringin were observed by TLC and HPLC. The major glycosylation product was purified by using a Sephadex LH-20 column. The sturcture was determined by using MALDI-TOF MS, methylation analysis, and (1)H and (13)C NMR. The major transglycosylation product was maltosylnaringin, in which the maltose unit was attached by an alpha-1-->6 glycosidic linkage to the D-glucose moiety of naringin. This product was 250 times more soluble in water and 10 times less bitter than naringin.
Lu, Lili; Jin, Lan; Liu, Jiawei; Song, Deyong; Guo, Zhongwu; Xiao, Min
2014-01-01
β-Fructosidases are a widespread group of enzymes that catalyze the hydrolysis of terminal fructosyl units from various substrates. These enzymes also exhibit transglycosylation activity when they function with high concentrations of sucrose, which is used to synthesize fructooligosaccharides (FOS) in the food industry. A β-fructosidase (BfrA) with high transglycosylation activity was purified from Aspergillus oryzae FS4 as a monomeric glycoprotein. Compared with the most extensively studied Aspergillus spp. fructosidases that synthesize inulin-type β-(2-1)-linked FOS, BfrA has unique transfructosylating property of synthesizing levan- and neolevan-type β-(2-6)-linked FOS. The coding sequence (bfrAFS4, 1.86 kb) of BfrA was amplified and expressed in Escherichia coli and Pichia pastoris. Both native and recombinant proteins showed transfructosylation and hydrolyzation activities with broad substrate specificity. These proteins could hydrolyze the following linkages: Glc α-1, 2-β Fru; Glc α-1, 3-α Fru; and Glc α-1, 5-β Fru. Compared with the unglycosylated E. coli-expressed BfrA (E.BfrA), the N-glycosylated native (N.BfrA) and the P. pastoris-expressed BfrA (P.BfrA) were highly stable at a wide pH range (pH 4 to 11), and significantly more thermostable at temperatures up to 50°C with a maximum activity at 55°C. Using sucrose as substrate, the Km and kcat values for total activity were 37.19±5.28 mM and 1.0016±0.039×104 s−1 for N.BfrA. Moreover, 10 of 13 putative N-glycosylation sites were glycosylated on N.BfrA, and N-glycosylation was essential for enzyme thermal stability and optima activity. Thus, BfrA has demonstrated as a well-characterized A. oryzae fructosidase with unique transfructosylating capability of synthesizing levan- and neolevan-type FOS. PMID:25501957
Rodríguez-Díaz, Jesús; Carbajo, Rodrigo J.; Pineda-Lucena, Antonio; Monedero, Vicente
2013-01-01
AlfB and AlfC α-l-fucosidases from Lactobacillus casei were used in transglycosylation reactions, and they showed high efficiency in synthesizing fucosyldisaccharides. AlfB and AlfC activities exclusively produced fucosyl-α-1,3-N-acetylglucosamine and fucosyl-α-1,6-N-acetylglucosamine, respectively. The reaction kinetics showed that AlfB can convert 23% p-nitrophenyl-α-l-fucopyranoside into fucosyl-α-1,3-N-acetylglucosamine and AlfC at up to 56% into fucosyl-α-1,6-N-acetylglucosamine. PMID:23542622
Baek, Jin-Sook; Kim, Hye-Young; Abbott, Thomas P; Moon, Tae-Wha; Lee, Soo-Bok; Park, Cheon-Seok; Park, Kwan-Hwa
2003-03-01
Simmondsin was modified with acarviosine-glucose using the transglycosylation activity of Thermus maltogenic amylase to synthesize a novel compound with both antiobesity and hypoglycemic activity. The LC/MS and 13C NMR analyses confirmed that the structure of the major transglycosylation product was acarviosine-simmondsin (Acv-simmondsin), in which acarviosine was attached to the glucose moiety of simmondsin by an alpha-(1,6)-glycosidic linkage. It was found that Acv-simmondsin was a potent competitive inhibitor of alpha-glucosidase with the Ki value of 0.69 microM and a mixed type inhibitor of alpha-amylase with the Ki and KI of 20.78 microM and 26.31 microM, respectively. The administration of Acv-simmondsin (0.1 g/100 g diet/day) to mice for 5 days significantly reduced food intake by 35%, compared to 25% with simmondsin in control obese mice. Acv-simmondsin (50 mg/kg BW) suppressed the postprandial blood glucose response to sucrose (1 g/kg BW) by 74%, compared to 71% with acarbose, in normal rats.
Kováčová, Kristína; Farkaš, Vladimír
2016-04-01
Polysaccharide endotransglycosylases (PETs) are the cell wall-modifying enzymes of fungi and plants. They catalyze random endo-splitting of the polysaccharide donor molecule and transfer of the newly formed reducing sugar residue to the nonreducing end of an acceptor molecule which can be a polysaccharide or an oligosaccharide. Owing to their important role in the cell wall formation, the inhibition of PETs represents an attractive strategy in the fight against fungal infections. We have elaborated two variants of a versatile high-throughput microplate fluorimetric assay that could be used for effective identification of PETs and screening of their inhibitors. Both assays use the respective polysaccharides as the donors and sulforhodamine-labeled oligosaccharides as the acceptors but differ from each other by mode of how the labeled polysaccharide products of transglycosylation are separated from the unreacted oligosaccharide acceptors. In the first variant, the reactions take place in a layer of agar gel laid on the bottoms of the wells of a microtitration plate. After the reaction, the high-Mr transglycosylation products are precipitated with 66 % ethanol and retained within the gel while the low-Mr products and the unreacted acceptors are washed out. In the second variant, the donor polysaccharides are adsorbed to the surface of a microplate well and remain adsorbed there also after becoming labeled in the course of the transglycosylation reaction whereas the unused low-Mr acceptors are washed out. As a proof of versatility, assays of heterologously expressed transglycosylases ScGas1, ScCrh1, and ScCrh2 from the yeast Saccharomyces cerevisiae, CaPhr1 and CaPhr2 from Candida albicans, and of a plant xyloglucan endotransglycosylase (XET) are demonstrated.
Introducing N-glycans into natural products through a chemoenzymatic approach.
Huang, Wei; Ochiai, Hirofumi; Zhang, Xinyu; Wang, Lai-Xi
2008-11-24
The present study describes an efficient chemoenzymatic method for introducing a core N-glycan of glycoprotein origin into various lipophilic natural products. It was found that the endo-beta-N-acetylglucosaminidase from Arthrobactor protophormiae (Endo-A) had broad substrate specificity and can accommodate a wide range of glucose (Glc)- or N-acetylglucosamine (GlcNAc)-containing natural products as acceptors for transglycosylation, when an N-glycan oxazoline was used as a donor substrate. Using lithocholic acid as a model compound, we have shown that introduction of an N-glycan could be achieved by a two-step approach: chemical glycosylation to introduce a monosaccharide (Glc or GlcNAc) as a handle, and then Endo-A catalyzed transglycosylation to accomplish the site-specific N-glycan attachment. For those natural products that already carry terminal Glc or GlcNAc residues, direct enzymatic transglycosylation using sugar oxazoline as the donor substrate was achievable to introduce an N-glycan. It was also demonstrated that simultaneous double glycosylation could be fulfilled when the natural product contains two Glc residues. This chemoenzymatic method is concise, site-specific, and highly convergent. Because N-glycans of glycoprotein origin can serve as ligands for diverse lectins and cell-surface receptors, introduction of a defined N-glycan into biologically significant natural products may bestow novel properties onto these natural products for drug discovery and development.
Crombie, H J; Chengappa, S; Hellyer, A; Reid, J S
1998-07-01
A beta-D-glucosidase has been purified to apparent homogeneity from the cotyledons of germinated nasturtium (Tropaeolum majus L.) seedlings during the mobilization of the xyloglucan stored in the cotyledonary cell walls. The purified protein (Mr 76, 000; a glycoprotein; pl > 9.5; apparent pH optimum 4.5; temperature optimum 30 degrees C) catalysed the hydrolysis of p-nitrophenyl-beta-D-glucopyranoside, cello-oligosaccharides, beta-linked glucose disaccharides, and certain xyloglucan oligosaccharides. Glucose disaccharides with different linkages were hydrolysed at different rates [(1-->3) > (1-->4) > (1-->2) > (1-->6)] with significant transglycosylation occurring in the early stages of the reaction. Cello-oligosaccharide hydrolysis was also accompanied by extensive transglycosylation to give transitory accumulations of higher oligosaccharides. At least some of the glycosyl linkages formed during transglycosylation were (1-->6)-beta. Xyloglucan oligosaccharides xylose-substituted at the non-reducing terminal glucose residue (XXXG, XXLG, XLXG and XLLG, where G is an unsubstituted glucose residue, X is a xylose-substituted glucose residue, and L is a galactosylxylose-substituted glucose residue) were not hydrolysed. Some xyloglucan oligosaccharides with an unsubstituted non-reducing terminal glucose residue (GXXG, GXLG and GXG) were hydrolysed, but others (GLXG and GLLG) were not. This indicated steric hindrance by L but not X substitution at the glucose residue next to the one at the non-reducing end of the oligosaccharide. Hydrolysis of xyloglucan oligosaccharides was not accompanied by transglycosylation. Natural xyloglucan subunit oligosaccharides (XXXG, XXLG, XLXG, XLLG) were totally degraded to their monosaccharide components when treated with nasturtium beta-D-galactosidase. (Edwards et al (1988) J. Biol. Chem. 263, 4333-4337), followed by alternations of nasturtium xyloglucan-specific alpha-xylosidase (Fanutti et al (1991) Planta 184, 137-147) and this enzyme. Several extensively overlapping cDNA clones were obtained by RT-PCR and by screening cDNA libraries. A composite, full-length DNA had an open reading frame of 1962 bp, encoding a polypeptide of 654 amino acids, including all N-terminal and internal sequences obtained from the purified beta-glucosidase protein, and a motif resembling plant signal sequences thought to direct proteins to the cell wall. Database searches revealed homology with beta-glucosidases from several sources (plant, bacteria, yeast), notably with glycosylhydrolases of 'Family 3', according to the classification of Henrissat (Henrissat (1991) Biochem. J. 280, 309-316). There was strong sequence homology with a beta-glucan exo-hydrolase from barley (Hrmova et al. (1996) J. Biol. Chem. 271, 5277-5286). The nasturtium beta-glucosidase is ascribed a role in xyloglucan mobilization, and its interaction with the alpha-xylosidase and the beta-galactosidase is modelled.
Zhou, Junpei; Liu, Yu; Lu, Qian; Zhang, Rui; Wu, Qian; Li, Chunyan; Li, Junjun; Tang, Xianghua; Xu, Bo; Ding, Junmei; Han, Nanyu; Huang, Zunxi
2016-03-23
α-Galactosidases are of great interest in various applications. A glycoside hydrolase family 27 α-galactosidase was cloned from Pontibacter sp. harbored in a saline soil and expressed in Escherichia coli. The purified recombinant enzyme (rAgaAHJ8) was little or not affected by 3.5-30.0% (w/v) NaCl, 10.0-100.0 mM Pb(CH3COO)2, 10.0-60.0 mM ZnSO4, or 8.3-100.0 mg mL(-1) trypsin and by most metal ions and chemical reagents at 1.0 and 10.0 mM concentrations. The degree of synergy on enzymatic degradation of locust bean gum and guar gum by an endomannanase and rAgaAHJ8 was 1.22-1.54. In the presence of trypsin, the amount of reducing sugars released from soybean milk treated by rAgaAHJ8 was approximately 3.8-fold compared with that treated by a commercial α-galactosidase. rAgaAHJ8 showed transglycosylation activity when using sucrose, raffinose, and 3-methyl-1-butanol as the acceptors. Furthermore, potential factors for salt adaptation of the enzyme were presumed.
Kralj, Slavko; Leeflang, Chris; Sierra, Estefanía Ibáñez; Kempiński, Błażej; Alkan, Veli; Kolkman, Marc
2018-01-01
Fructooligosaccharides (FOS) and inulin, composed of β-2-1 linked fructose units, have a broad range of industrial applications. They are known to have various beneficial health effects and therefore have broad application potential in nutrition. For (modified) inulin also for non-food purposes more applications are arising. Examples are carboxymethylated inulin as anti-scalant and carboymlated inulin as emulsifiers. Various plants synthesize FOS and/or inulin type of fructans. However, isolating of FOS and inulin from plants is challenging due to for instance varying chains length. There is an increasing demand for FOS and inulin oligosaccharides and alternative procedures for their synthesis are attractive. We identified and characterized two fructosyltransferases from Bacillus agaradhaerens WDG185. FosA, a β-fructofuranosidase, synthesises short chain fructooligosaccharides (GF2-GF4) at high sucrose concentration, whereas InuO, an inulosucrase, synthesises a broad range of inulooligosaccharides (GF2-GF24) from sucrose, very similar to plant derived inulin. FosA and InuO showed activity over a broad pH range from 6 to 10 and optimal temperature at 60°C. Calcium ions and EDTA were found to have no effect on the activity of both enzymes. Kinetic analysis showed that only at relatively low substrate concentrations both enzymes showed Michaelis-Menten type of kinetics for total and transglycosylation activity. Both enzymes showed increased transglycosylation upon increasing substrate concentrations. These are the first examples of the molecular and biochemical characterization of a β-fructofuranosidase (FosA) and an inulosucrase enzyme (InuO) and its product from a Bacillus agaradhaerens strain. Copyright © 2017 Elsevier Ltd. All rights reserved.
Saura-Valls, Marc; Fauré, Régis; Ragàs, Sergi; Piens, Kathleen; Brumer, Harry; Teeri, Tuula T.; Cottaz, Sylvain; Driguez, Hugues; Planas, Antoni
2005-01-01
Plant XETs [XG (xyloglucan) endotransglycosylases] catalyse the transglycosylation from a XG donor to a XG or low-molecular-mass XG fragment as the acceptor, and are thought to be important enzymes in the formation and remodelling of the cellulose-XG three-dimensional network in the primary plant cell wall. Current methods to assay XET activity use the XG polysaccharide as the donor substrate, and present limitations for kinetic and mechanistic studies of XET action due to the polymeric and polydisperse nature of the substrate. A novel activity assay based on HPCE (high performance capillary electrophoresis), in conjunction with a defined low-molecular-mass XGO {XG oligosaccharide; (XXXGXXXG, where G=Glcβ1,4- and X=[Xylα1,6]Glcβ1,4-)} as the glycosyl donor and a heptasaccharide derivatized with ANTS [8-aminonaphthalene-1,3,6-trisulphonic acid; (XXXG-ANTS)] as the acceptor substrate was developed and validated. The recombinant enzyme PttXET16A from Populus tremula x tremuloides (hybrid aspen) was characterized using the donor/acceptor pair indicated above, for which preparative scale syntheses have been optimized. The low-molecular-mass donor underwent a single transglycosylation reaction to the acceptor substrate under initial-rate conditions, with a pH optimum at 5.0 and maximal activity between 30 and 40 °C. Kinetic data are best explained by a ping-pong bi-bi mechanism with substrate inhibition by both donor and acceptor. This is the first assay for XETs using a donor substrate other than polymeric XG, enabling quantitative kinetic analysis of different XGO donors for specificity, and subsite mapping studies of XET enzymes. PMID:16356166
Saura-Valls, Marc; Fauré, Régis; Ragàs, Sergi; Piens, Kathleen; Brumer, Harry; Teeri, Tuula T; Cottaz, Sylvain; Driguez, Hugues; Planas, Antoni
2006-04-01
Plant XETs [XG (xyloglucan) endotransglycosylases] catalyse the transglycosylation from a XG donor to a XG or low-molecular-mass XG fragment as the acceptor, and are thought to be important enzymes in the formation and remodelling of the cellulose-XG three-dimensional network in the primary plant cell wall. Current methods to assay XET activity use the XG polysaccharide as the donor substrate, and present limitations for kinetic and mechanistic studies of XET action due to the polymeric and polydisperse nature of the substrate. A novel activity assay based on HPCE (high performance capillary electrophoresis), in conjunction with a defined low-molecular-mass XGO {XG oligosaccharide; (XXXGXXXG, where G=Glcbeta1,4- and X=[Xylalpha1,6]Glcbeta1,4-)} as the glycosyl donor and a heptasaccharide derivatized with ANTS [8-aminonaphthalene-1,3,6-trisulphonic acid; (XXXG-ANTS)] as the acceptor substrate was developed and validated. The recombinant enzyme PttXET16A from Populus tremula x tremuloides (hybrid aspen) was characterized using the donor/acceptor pair indicated above, for which preparative scale syntheses have been optimized. The low-molecular-mass donor underwent a single transglycosylation reaction to the acceptor substrate under initial-rate conditions, with a pH optimum at 5.0 and maximal activity between 30 and 40 degrees C. Kinetic data are best explained by a ping-pong bi-bi mechanism with substrate inhibition by both donor and acceptor. This is the first assay for XETs using a donor substrate other than polymeric XG, enabling quantitative kinetic analysis of different XGO donors for specificity, and subsite mapping studies of XET enzymes.
Crystal Structure of Bacillus subtilis α-Amylase in Complex with Acarbose
Kagawa, Masayuki; Fujimoto, Zui; Momma, Mitsuru; Takase, Kenji; Mizuno, Hiroshi
2003-01-01
The crystal structure of Bacillus subtilis α-amylase, in complex with the pseudotetrasaccharide inhibitor acarbose, revealed an hexasaccharide in the active site as a result of transglycosylation. After comparison with the known structure of the catalytic-site mutant complexed with the native substrate maltopentaose, it is suggested that the present structure represents a mimic intermediate in the initial stage of the catalytic process. PMID:14617662
Vaikuntapu, Papa Rao; Mallakuntla, Mohan Krishna; Das, Subha Narayan; Bhuvanachandra, Bhoopal; Ramakrishna, Bellamkonda; Nadendla, Sandhya Rani; Podile, Appa Rao
2018-05-22
Chitin and its derivatives are used for a variety of applications. Flavobacterium johnsoniae UW101 is an aerobic Gram-negative bacterium. Genome analysis of F. johnsoniae UW101 revealed the presence of 10 glycoside hydrolases (GHs) that may degrade or modify chitin. The gene encoding chitinase B (FjchiB), which encodes a single catalytic GH18 domain has been cloned and heterologously expressed in Escherichia coli. FjChiB was optimally active in 50 mM sodium citrate buffer (pH 6.0) at 40 °C. FjChiB was salt-tolerant and catalytically versatile, with substrate specificity towards 75% DDA (degree of de-acetylation) chitosan, followed by colloidal chitin. Chitotetraose (DP4) was the shortest of the oligomeric substrates used by FjChiB. The K m and V max values of FjChiB for colloidal chitin were 49.38 mg/ml and 11.2 nanokat mg -1 , respectively. The overall catalytic efficiency (k c at /K m ) of FjChiB was 1.40 × 10 3 mg -1 ml s -1 . FjChiB exhibited transglycosylation (TG) with chitopentaose (DP5) and chitohexaose (DP6) substrates. The TG by FjChiB was fine-tuned by introducing a tryptophan (G106W) and asparagine (D148N) in the highly conserved catalytic groove and catalytic center, respectively. Hydrolytic products profile and homology modelling indicated that FjChiB is an endochitinase that holds promise for the conversion of chitin into useful products through both TG and/or hydrolysis. Copyright © 2018 Elsevier B.V. All rights reserved.
Guzmán-Rodríguez, Francisco; Alatorre-Santamaría, Sergio; Gómez-Ruiz, Lorena; Rodríguez-Serrano, Gabriela; García-Garibay, Mariano; Cruz-Guerrero, Alma
2018-05-02
Fucosylated oligosaccharides, such as 2'-fucosyllactose in human milk, have important biological functions such as prebiotics and preventing infection. In this work, the effect of an acceptor substrate (lactose) and the donor substrate 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) on the synthesis of a fucosylated trisaccharide was studied in a transglycosylation reaction using α-L-fucosidase from Thermotoga maritima. Conducting a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), it was demonstrated that synthesized oligosaccharide corresponded to a fucosylated trisaccharide, and high-performance liquid chromatography (HPLC) of the hydrolyzed compound confirmed it was fucosyllactose. As the concentration of the acceptor substrate increased, the concentration and synthesis rate of the fucosylated trisaccharide also increased, and the highest concentration obtained was 0.883 mM (25.2% yield) when using the higher initial lactose concentration (584 mM). Furthermore, the lower donor/acceptor ratio had the highest synthesis, so at the molar ratio of 0.001, a concentration of 0.286 mM was obtained (32.5% yield).
Generation of a Mutant Mucor hiemalis Endoglycosidase That Acts on Core-fucosylated N-Glycans.
Katoh, Toshihiko; Katayama, Takane; Tomabechi, Yusuke; Nishikawa, Yoshihide; Kumada, Jyunichi; Matsuzaki, Yuji; Yamamoto, Kenji
2016-10-28
Endo-β-N-acetylglucosaminidase M (Endo-M), an endoglycosidase from the fungus Mucor hiemalis, is a useful tool for chemoenzymatic synthesis of glycoconjugates, including glycoprotein-based therapeutics having a precisely defined glycoform, by virtue of its transglycosylation activity. Although Endo-M has been known to act on various N-glycans, it does not act on core-fucosylated N-glycans, which exist widely in mammalian glycoproteins, thus limiting its application. Therefore, we performed site-directed mutagenesis on Endo-M to isolate mutant enzymes that are able to act on mammalian-type core-α1,6-fucosylated glycans. Among the Endo-M mutant enzymes generated, those in which the tryptophan at position 251 was substituted with alanine or asparagine showed altered substrate specificities. Such mutant enzymes exhibited increased hydrolysis of a synthetic α1,6-fucosylated trimannosyl core structure, whereas their activity on the afucosylated form decreased. In addition, among the Trp-251 mutants, the W251N mutant was most efficient in hydrolyzing the core-fucosylated substrate. W251N mutants could act on the immunoglobulin G-derived core-fucosylated glycopeptides and human lactoferrin glycoproteins. This mutant was also capable of transferring the sialyl glycan from an activated substrate intermediate (sialyl glyco-oxazoline) onto an α1,6-fucosyl-N-acetylglucosaminyl biotin. Furthermore, the W251N mutant gained a glycosynthase-like activity when a N175Q substitution was introduced and it caused accumulation of the transglycosylation products. These findings not only give insights into the substrate recognition mechanism of glycoside hydrolase family 85 enzymes but also widen their scope of application in preparing homogeneous glycoforms of core-fucosylated glycoproteins for the production of potent glycoprotein-based therapeutics. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Biochemical and kinetic analysis of the GH3 family beta-xylosidase from Aspergillus awamori X-100.
Eneyskaya, Elena V; Ivanen, Dina R; Bobrov, Kirill S; Isaeva-Ivanova, Lyudmila S; Shabalin, Konstantin A; Savel'ev, Andrew N; Golubev, Alexander M; Kulminskaya, Anna A
2007-01-15
The beta-xylosidase from Aspergillus awamori X-100 belonging to the family 3 glycoside hydrolase revealed a distinctive transglycosylating ability to produce xylooligosaccharides with degree of polymerization more than 7. In order to explain this fact, the enzyme has been subjected to the detailed biochemical study. The enzymatic hydrolysis of p-nitrophenyl beta-D-xylopyranoside was found to occur with overall retention of substrate anomeric configuration suggesting cleavage of xylosidic bonds through a double-displacement mechanism. Kinetic study with aryl beta-xylopyranosides substrates, in which leaving group pK(a)s were in the range of 3.96-10.32, revealed monotonic function of log(k(cat)) and no correlation of log(k(cat)/Km) versus pKa values indicating deglycosylation as a rate-limiting step for the enzymatic hydrolysis. The classical bell-shaped pH dependence of k(cat)/Km indicated two ionizable groups in the beta-xylosidase active site with apparent pKa values of 2.2 and 6.4. The kinetic parameters of hydrolysis, Km and k(cat), of p-nitrophenyl beta-D-1,4-xylooligosaccharides were very close to those for hydrolysis of p-nitrophenyl-beta-D-xylopyranoside. Increase of p-nitrophenyl-beta-D-xylopyranoside concentration up to 80 mM led to increasing of the reaction velocity resulting in k(cat)(app)=81 s(-1). Addition of alpha-methyl D-xylopyranoside to the reaction mixture at high concentration of p-nitrophenyl-beta-D-xylopyranoside (50 mM) caused an acceleration of the beta-xylosidase-catalyzed reactions and appearance of a new transglycosylation product, alpha-methyl D-xylopyranosyl-1,4-beta-D-xylopyranoside, that was identified by 1H NMR spectroscopy. The kinetic model suggested for the enzymatic reaction was consistent with the results obtained.
Moreira, Ana S P; Nunes, Fernando M; Simões, Cristiana; Maciel, Elisabete; Domingues, Pedro; Domingues, M Rosário M; Coimbra, Manuel A
2017-07-15
Under roasting conditions, polysaccharides depolymerize and also are able to polymerize, forming new polymers through non-enzymatic transglycosylation reactions (TGRs). TGRs can also occur between carbohydrates and aglycones, such as the phenolic compounds present in daily consumed foods like coffee. In this study, glycosidically-linked phenolic compounds were quantified in coffee melanoidins, the polymeric nitrogenous brown-colored compounds formed during roasting, defined as end-products of Maillard reaction. One third of the phenolics present were in glycosidically-linked form. In addition, the roasting of solid-state mixtures mimicking coffee beans composition allowed the conclusion that proteins play a regulatory role in TGRs extension and, consequently, modulate melanoidins composition. Overall, the results obtained showed that TGRs are a main mechanism of phenolics incorporation in melanoidins and are inhibited by amino groups through Maillard reaction. Copyright © 2017 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, Kyung-Mo; Shim, Jae-Hoon; Park, Jong-Tae
2010-06-18
The transglycosylation reaction of maltodextrin glucosidase (MalZ) cloned and purified from Escherichia coli K12 was characterized and applied to the synthesis of branched oligosaccharides. Purified MalZ preferentially catalyzed the hydrolysis of maltodextrin, {gamma}-cyclodextrin (CD), and cycloamylose (CA). In addition, when the enzyme was incubated with 5% maltotriose (G3), a series of transfer products were produced. The resulting major transfer products, annotated as T1, T2, and T3, were purified and their structures were determined by TLC, MALDI-TOF/MS, {sup 13}C NMR, and enzymatic analysis. T1 was identified as a novel compound, maltosyl {alpha}-1,3-maltose, whereas T2 and T3 were determined to be isopanosemore » and maltosyl-{alpha}-1,6-maltose, respectively. These results indicated that MalZ transferred sugar moiety mainly to C-3 or C-6-OH of glucose of the acceptor molecule. To obtain highly concentrated transfer products, the enzyme was reacted with 10% liquefied cornstarch, and then glucose and maltose were removed by immobilized yeast. The T1 content of the resulting reaction mixture reached 9.0%. The mixture of T1 containing a nigerose moiety can have an immunopotentiating effect on the human body and may be a potential functional sugar stuff.« less
Cloning and sequencing of CGTase genes of two Thermoanaerobacter strains
USDA-ARS?s Scientific Manuscript database
Cyclodextrin glycosyltransferase (CGTase; EC 2.4.1.19) is an important industrial enzyme that catalyzes the formation of cyclodextrins from starch and related substrates via transglycosylation reaction. Cyclodextrins are cyclic oligosaccharides, composed of 6,7 or 8 glucose units, which are used in...
Synthesis of galactooligosaccharides by CBD fusion β-galactosidase immobilized on cellulose.
Lu, Lili; Xu, Shuze; Zhao, Renfei; Zhang, Dayu; Li, Zhengyi; Li, Yumei; Xiao, Min
2012-07-01
The β-galactosidase gene (bgaL3) was cloned from Lactobacillus bulgaricus L3 and fused with cellulose binding domain (CBD) using pET-35b (+) vector in Escherichia coli. The resulting fusion protein (CBD-BgaL3) was directly adsorbed onto microcrystalline cellulose with a high immobilization efficiency of 61%. A gram of cellulose was found to absorb 97.6 U of enzyme in the solution containing 100mM NaCl (pH 5.8) at room temperature for 20 min. The enzymatic and transglycosylation characteristics of the immobilized CBD-BgaL3 were similar to the free form. Using the immobilized enzyme as the catalyst, the yield of galactooligosaccharides (GOS) reached a maximum of 49% (w/w) from 400 g/L lactose (pH 7.6) at 45 °C for 75 min, with a high productivity of 156.8 g/L/h. Reusability assay was subsequently performed under the same reaction conditions. The immobilized enzyme could retain over 85% activity after twenty batches with the GOS yields all above 40%. Copyright © 2012 Elsevier Ltd. All rights reserved.
[Expression and characterization of a neutral Enterobacter cloacae GX-3 invertase].
Zhao, Yingli; Wu, Qianqian; Zhang, Zhikai; Wang, Zilong; Wei, Yutuo; Huang, Ribo; Du, Liqin
2015-04-04
To characterize a neutral invertase from Enterobacter cloacae GX-3. By searching GenBank database, we found the genes encoding invertase from the same genus Enterobacter. These sequences were aligned and analyzed. Then, a gene encoding neutral invertase was amplified by PCR. The recombinant plasmid pQE-Einv was constructed. We purified the expressed protein Einv with nickel-nitrilotriacetic acid chromatography. At last, the characterics of the recombinant protein Einv were studied in detail. A gene encoding neutral invertase was discovered and cloned from E. cloacae GX-3. The recombinant enzyme Einv was characterized. Einv had an optimum pH of 6.5 and an optimum temperature of 40 degrees C. The results of sodium dodecyl sulfate polyacrylamide gel electropheresis (SDS-PAGE) and gel permeation chromatography ( GPC) showed that Einv was a homo-dimer protein. Einv retained 80% activity at sucrose concentrations up to 1170 mmol/L. But, Einv had no transglycosylation activity at high sucrose concentration. It could hydrolyze raffinose, 1-kestose, nystose, fructofuranosylnystose and stachyose. It is first reported that an invertase from Enterobacter cloacae is a beta-fructofuranosidase at neutral pH range. It only has hydrolysis activity without tranglycosylation activity. These characteristics indicate that the neutral invertase Einv has important applications in food industry.
Tiné; Cortelazzo; Buckeridge
2000-05-29
Many seeds contain storage compounds that are used by the embryo/plantlet as a source of nutrients after germination. In seeds of Hymenaea courbaril, a leguminous tree, the main reserve consists of a structurally unusual xyloglucan stored in thickened walls of the cotyledon cells. The present work aimed to study H. courbaril xyloglucan metabolism during and after germination in order to compare its degrading system with the other known xyloglucan containing seeds. Polysaccharide degradation occurred after germination between 35 and 55 days after planting. The activities of alpha-xylosidase, beta-glucosidase, beta-galactosidase and XET rose during the period of xyloglucan disassembling but a low level of endo-beta-glucanase activity was detected, suggesting that this XET has high affinity for the oligosaccharides. The pH optimum of beta-galactosidase was different from the alpha-xylosidase, beta-glucosidase and XET optima suggesting that the former may be important in the control of the mobilisation process. A tentative model for xyloglucan disassembling in vivo is proposed, where beta-galactosidase allows the free oligosaccharides to bypass a transglycosylation cycle and be disassembled by the other exo-enzymes. Some ecophysiological comparisons among H. courbaril and other xyloglucan storing seeds are discussed.
2017-01-01
Summary Bionic acids are bioactive compounds demonstrating numerous interesting properties. They are widely produced by chemical or enzymatic oxidation of disaccharides. This paper focuses on the galactosyl derivative of gluconic acid as a result of a new method of bionic acid synthesis which utilises the transglycosylation properties of β-galactosidase and introduces lactose as a substrate. Products obtained in such a process are characterised by different structures (and, potentially, properties) than those resulting from traditional oxidation of disaccharides. The aim of this study is to determine the effect of selected parameters (concentration and ratio of substrates, dose of the enzyme, time, pH, presence of salts) on the course of the reaction carried out with the enzymatic preparation Lactozym, containing β-galactosidase from Kluyveromyces lactis. Research has shown that increased dry matter content in the baseline solution (up to 50%, by mass per volume) and an addition of NaCl contribute to higher yield. On the other hand, reduced content of the derivative is a result of increased pH from 7.0 to 9.0 and an addition of magnesium and manganese salts. Moreover, exceeding the β-galactosidase dose over approx. 35 000 U per 100 g of lactose also leads to reduced yield of the process. The most favourable molar ratio of sodium gluconate to lactose is 2.225:0.675. Depending on the conditions of the synthesis, the product concentration ranged between 17.3 and 118.3 g/L of the reaction mixture, which corresponded to the mass fraction of 6.64–23.7% of dry matter. The data obtained as a result of the present study may be useful for designing an industrial process. PMID:28867957
Ferreira, Alexandre H P; Terra, Walter R; Ferreira, Clélia
2003-02-01
The midgut of the yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae) larvae has four beta-glycosidases. The properties of two of these enzymes (betaGly1 and betaGly2) have been described elsewhere. In this paper, the characterization of the other two glycosidases (betaGly3 and betaGly4) is described. BetaGly3 has one active site, hydrolyzes disaccharides, cellodextrins, synthetic substrates and beta-glucosides produced by plants. The enzyme is inhibited by amygdalin, cellotriose, cellotetraose and cellopentaose in high concentrations, probably due to transglycosylation. betaGly3 hydrolyzes beta 1,4-glycosidic linkages with a catalytic rate independent of the substrate polymerization degree (k(int)) of 11.9 s(-1). Its active site is formed by four subsites, where subsites +1 and -1 bind glucose residues with higher affinity than subsite +2. The main role of betaGly3 seems to be disaccharide hydrolysis. BetaGly4 is a beta-galactosidase, since it has highest activity against beta-galactosides. It can also hydrolyze fucosides, but not glucosides, and has Triton X-100 as a non-essential activator (K(a)=15 microM, pH 4.5). betaGly4 has two active sites that can hydrolyze p-nitrophenyl beta-galactoside (NPbetaGal). The one hydrolyzing NPbetaGal with more efficiency is also active against methylumbellipheryl beta-D-galactoside and lactose. The other active site hydrolyzes NPbetaFucoside and binds NPbetaGal weakly. BetaGly4 hydrolyzes hydrophobic substrates with high catalytical efficiency and is able to bind octyl-beta-thiogalactoside in its active site with high affinity. The betaGly4 physiological role is supposed to be the hydrolysis of galactolipids that are found in membranes from vegetal tissues. As the enzyme has a hydrophobic site where Triton X-100 can bind, it might be activated by membrane lipids, thus becoming fully active only at the surface of cell membranes.
Madhuprakash, Jogi; El Gueddari, Nour Eddine; Moerschbacher, Bruno M; Podile, Appa Rao
2015-12-01
The biological activities of chitosan and its oligosaccharides are greatly influenced by properties such as the degree of polymerization (DP), degree of acetylation (DA) and pattern of acetylation (PA). Here, structurally diverse chitosan oligosaccharides from chitosan polymers (DA=35% or 61%) were generated using Serratia proteamaculans wild-type chitinase D (SpChiD) and the W114A mutant which lacks transglycosylase activity. The crude oligosaccharide mixtures and purified fractions with specific DP and DA ranges were tested for their ability to induce an oxidative burst in rice cell suspension cultures. The crude mixtures were more active when produced by the W114A mutant whereas the purified fractions were more active when produced by wild-type SpChiD. Neither hydrolysis nor transglycosylation by SpChiD was inhibited in the presence of fully-deacetylated oligosaccharides, suggesting that SpChiD could be exploited to generate oligosaccharides with defined DA and PA values. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kulminskaya, Anna A; Arand, Michael; Eneyskaya, Elena V; Ivanen, Dina R; Shabalin, Konstantin A; Shishlyannikov, Sergei M; Saveliev, Andrew N; Korneeva, Olga S; Neustroev, Kirill N
2003-08-21
1H-NMR analysis was applied to investigate the hydrolytic activity of Aspergillus awamori inulinase. The obtained NMR signals and deduced metabolite pattern revealed that the enzyme cleaves off only fructose from inulin and does not possess transglycosylating activity. Kinetics for the enzyme hydrolysis of inulooligosaccharides with different degree of polymerization (d.p.) were recorded. The enzyme hydrolyzed both beta2,1- as well as beta2,6-fructosyl linkages in fructooligosaccharides. From the k(cat)/K(m) ratios obtained with inulooligosaccharides with d.p. from 2 to 7, we deduce that the catalytic site of the inulinase contains at least five fructosyl-binding sites and can be classified as exo-acting enzyme. Product analysis of inulopentaose and inulohexaose hydrolysis by the Aspergillus inulinase provided no evidence for a possible multiple-attack mode of action, suggesting that the enzyme acts exclusively as an exoinulinase.
Madhuprakash, Jogi; Tanneeru, Karunakar; Karlapudi, Bhavana; Guruprasad, Lalitha; Podile, Appa Rao
2014-09-01
Transglycosylation (TG) activity is a property of glycosyl hydrolases (GHs) with which new glycosidic bonds are introduced between donor and acceptor sugar molecules. This special property of the GHs has potential to generate longer chain chitooligosaccharides (CHOS) that show elicitor activity in plants. We hypothesize that TG activity could be improved by retaining the substrate for a longer duration in the catalytic site. Four variants of chitinase D from Serratia proteamaculans (SpChiD) i.e. G119S, G119W, W120A and G201W were analyzed in detail for improved TG activity using high performance liquid chromatography (HPLC) and high resolution mass spectrometry (HRMS). The results were strongly supported by 50ns molecular dynamics (MD) simulations and estimated solvated interaction energies (SIE). The mutant G119W lost much of both hydrolytic and TG activities, while the mutant G201W displayed increased TG. The trajectory of MD simulations of the mutant G119W showed that the indole rings of two adjacent Trp residues create a major hindrance for the DP4 movement towards the catalytic center. Increased van der Waals (vdW) and coulombic interactions between DP4 substrate and the Trp-201 resulted in enhanced TG activity with the mutant G201W. The average number of hydrogen bonds observed for the DP4 substrate was increased for the mutants G119W and G201W compared to SpChiD. The increase in TG activity could be due to partial blocking of product exit of SpChiD. This new approach can be used for generating mutants of GHs with improved TG activity to produce longer chain oligosaccharides. Copyright © 2014 Elsevier B.V. All rights reserved.
In vitro activities of four xyloglucan endotransglycosylases from Arabidopsis
NASA Technical Reports Server (NTRS)
Campbell, P.; Braam, J.; McIntire, L. V. (Principal Investigator)
1999-01-01
Xyloglucan endotransglycosylases (XETs) are encoded by a gene family in Arabidopsis thaliana. These enzymes modify a major structural component of the plant cell wall, xyloglucan, and therefore may influence plant growth and development. We have produced four Arabidopsis XETs (TCH4, Meri-5, EXGT and XTR9) using the baculovirus/insect cell system and compared their biochemical activities. TCH4, as previously demonstrated, and the other three proteins are capable of carrying out transglycosylation of xyloglucans. The K(m) for XLLGol acceptor oligosaccharide is in the range of 20-40 microM for all the XETs except XTR9, which has a Km of 5 microM and is significantly inhibited by high levels of XLLGol. All four enzymes are most active between pH 6.0 and 6.5. TCH4 and XTR9 have temperature optima of 18 degrees C, whereas Meri-5 and EXGT are most active at 28 and 37 degrees C, respectively. Although the activity levels of three of the XETs are not influenced by the presence of fucose on the xyloglucan polymer, XTR9 has a clear preference for non-fucosylated xyloglucan polymer. The four XETs show a marked preference for XLLGol over either XXFGol or XXXGol as acceptor oligosaccharide. All four XETs are glycosylated; however, only the activities of TCH4 and Meri-5 are affected by the removal of the N-glycan with PNGase F. These four enzymes most likely function solely as transglycosylases because xyloglucan endoglucanase activity was not apparent. Subtle differences in biochemical activities may influence the physiological functions of the distinct XETs in vivo.
Vetere, A; Ferro, S; Bosco, M; Cescutti, P; Paoletti, S
1997-08-01
Beta-D-Xylopyranosides, such as p-nitrophenyl-beta-D-xylopyranoside (Xyl-Np) or 4-methylumbelliferyl-beta-D-xylopyranoside (Xyl-MeUmb), when added to the culture medium of human skin fibroblasts have previously been shown to produce some Np- or MeUmb-oligosaccharides related to the regulation of glycosaminoglycan biosynthesis. Among these oligosaccharide derivatives, we synthesized the trisaccharide derivative NeuAc(alpha2-3)Gal(beta1-4)Xyl-Np(beta1- as a potential inhibitor of human skin fibroblast glycosaminoglycan biosynthesis. This synthesis was achieved by sequential use of transglycosylating activities of Escherichia coli beta-galactosidase and Trypanosoma cruzi trans-sialidase. The structure of the oligosaccharide obtained was determined by HPLC, ion-spray mass spectrometry, and NMR.
Preparation of gentiooligosaccharides using Trichoderma viride β-glucosidase.
Wang, Fei; Wu, Jing; Chen, Sheng
2018-05-15
The recombinant plasmid pPIC9K-bgl1 containing β-glucosidase bgl1 from Trichoderma viride was constructed by overlapping PCR and integrated into Pichia pastoris KM71. In order to assist the formation of disulfide bonds and thus improve protein folding efficiency, protein disulfide isomerase pdi was co-expressed in the P. pastoris KM71/pPIC9K-bgl1/pPICZ-A-pdi strain, and fermentation in flasks resulted in enzyme activity of 143 U/ml. The enzyme activity of β-glucosidase reached 1402 U/ml following optimisation of fermentation conditions in a 3.6 l bioreactor. With 80% glucose as substrate, gentiooligosaccharides were synthesised by β-glucosidase-based reverse hydrolysis. A yield of 130 g/l was achieved with a conversion rate of 16.25%. With 20% glucose and 40% cellobiose as substrates, gentiooligosaccharides were synthesised by transglycosylation with a yield of 116 g/l and a conversion rate of 19.4%. Copyright © 2017 Elsevier Ltd. All rights reserved.
Matsuzawa, Tomohiko; Mitsuishi, Yasushi; Kameyama, Akihiko
2016-01-01
Aspergillus oryzae produces a unique β-glucosidase, isoprimeverose-producing oligoxyloglucan hydrolase (IPase), that recognizes and releases isoprimeverose (α-d-xylopyranose-(1→6)-d-glucopyranose) units from the non-reducing ends of oligoxyloglucans. A gene encoding A. oryzae IPase, termed ipeA, was identified and expressed in Pichia pastoris. With the exception of cellobiose, IpeA hydrolyzes a variety of oligoxyloglucans and is a member of the glycoside hydrolase family 3. Xylopyranosyl branching at the non-reducing ends was vital for IPase activity, and galactosylation at a α-1,6-linked xylopyranosyl side chain completely abolished IpeA activity. Hepta-oligoxyloglucan saccharide (Xyl3Glc4) substrate was preferred over tri- (Xyl1Glc2) and tetra- (Xyl2Glc2) oligoxyloglucan saccharides substrates. IpeA transferred isoprimeverose units to other saccharides, indicating transglycosylation activity. The ipeA gene was expressed in xylose and xyloglucan media and was strongly induced in the presence of xyloglucan endo-xyloglucanase-hydrolyzed products. This is the first study to report the identification of a gene encoding IPase in eukaryotes. PMID:26755723
Newman, Monica A.; Zebeli, Qendrim; Eberspächer, Eva; Grüll, Dietmar; Molnar, Timea; Metzler-Zebeli, Barbara U.
2017-01-01
Due to the functional properties and physiological effects often associated with chemically modified starches, significant interest lies in their development for incorporation in processed foods. This study investigated the effect of transglycosylated cornstarch (TGS) on blood glucose, insulin, and serum metabolome in the pre- and postprandial phase in growing pigs. Eight jugular vein-catheterized barrows were fed two diets containing 72% purified starch (waxy cornstarch (CON) or TGS). A meal tolerance test (MTT) was performed with serial blood sampling for glucose, insulin, lipids, and metabolome profiling. TGS-fed pigs had reduced postprandial insulin (p < 0.05) and glucose (p < 0.10) peaks compared to CON-fed pigs. The MTT showed increased (p < 0.05) serum urea with TGS-fed pigs compared to CON, indicative of increased protein catabolism. Metabolome profiling showed reduced (p < 0.05) amino acids such as alanine and glutamine with TGS, suggesting increased gluconeogenesis compared to CON, probably due to a reduction in available glucose. Of all metabolites affected by dietary treatment, alkyl-acyl-phosphatidylcholines and sphingomyelins were generally increased (p < 0.05) preprandially, whereas diacyl-phosphatidylcholines and lysophosphatidylcholines were decreased (p < 0.05) postprandially in TGS-fed pigs compared to CON. In conclusion, TGS led to changes in postprandial insulin and glucose metabolism, which may have caused the alterations in serum amino acid and phospholipid metabolome profiles. PMID:28300770
Newman, Monica A; Zebeli, Qendrim; Eberspächer, Eva; Grüll, Dietmar; Molnar, Timea; Metzler-Zebeli, Barbara U
2017-03-16
Due to the functional properties and physiological effects often associated with chemically modified starches, significant interest lies in their development for incorporation in processed foods. This study investigated the effect of transglycosylated cornstarch (TGS) on blood glucose, insulin, and serum metabolome in the pre- and postprandial phase in growing pigs. Eight jugular vein-catheterized barrows were fed two diets containing 72% purified starch (waxy cornstarch (CON) or TGS). A meal tolerance test (MTT) was performed with serial blood sampling for glucose, insulin, lipids, and metabolome profiling. TGS-fed pigs had reduced postprandial insulin ( p < 0.05) and glucose ( p < 0.10) peaks compared to CON-fed pigs. The MTT showed increased ( p < 0.05) serum urea with TGS-fed pigs compared to CON, indicative of increased protein catabolism. Metabolome profiling showed reduced ( p < 0.05) amino acids such as alanine and glutamine with TGS, suggesting increased gluconeogenesis compared to CON, probably due to a reduction in available glucose. Of all metabolites affected by dietary treatment, alkyl-acyl-phosphatidylcholines and sphingomyelins were generally increased ( p < 0.05) preprandially, whereas diacyl-phosphatidylcholines and lysophosphatidylcholines were decreased ( p < 0.05) postprandially in TGS-fed pigs compared to CON. In conclusion, TGS led to changes in postprandial insulin and glucose metabolism, which may have caused the alterations in serum amino acid and phospholipid metabolome profiles.
Expression and Characterization of a Novel Antifungal Exo-β-1,3-glucanase from Chaetomium cupreum.
Jiang, Cheng; Song, Jinzhu; Cong, Hua; Zhang, Junzheng; Yang, Qian
2017-05-01
A novel β-1,3-glucanase gene, designated Ccglu17A, was cloned from the biological control fungus Chaetomium cupreum Ame. Its 1626-bp open reading frame encoded 541 amino acids. The corresponding amino acid sequence showed highest identity (67 %) with a glycoside hydrolase family 17 β-1,3-glucanase from Chaetomium globosum. The recombinant protein Ccglu17A was successfully expressed in Pichia pastoris, and the enzyme was purified to homogeneity with 10.1-fold purification and 47.8 % recovery yield. The protein's molecular mass was approximately 65 kDa, and its maximum activity appeared at pH 5.0 and temperature 45 °C. Heavy metal ions Fe 2+ , Mn 2+ , Cu 2+ , Co 2+ , Ag + , and Hg 2+ had inhibitory effects on Ccglu17A, but Ba 2+ promoted the enzyme's activity. Ccglu17A exhibited high substrate specificity, almost exclusively catalyzing β-1,3-glycosidic bond cleavage in various polysaccharoses to liberate glucose. The enzyme had a Km of 2.84 mg/mL and Vmax of 10.7 μmol glucose/min/mg protein for laminarin degradation under optimal conditions. Ccglu17A was an exoglucanase with transglycosylation activity based on its hydrolytic properties. It showed potential antifungal activity with a degradative effect on cell walls and inhibitory action against the germination of pathogenic fungus. In conclusion, Ccglu17A is the first functional exo-1,3-β-glucanase to be identified from C. cupreum and has potential applicability in industry and agriculture.
Yamanoi, Takashi; Oda, Yoshiki; Katsuraya, Kaname; Inazu, Toshiyuki; Yamamoto, Kenji
2016-06-02
This study describes the complete nuclear magnetic resonance (NMR) spectral assignment of a bisecting hybrid-type oligosaccharide 1, transferred by Mucor hiemalis endo-β-N-acetylglucosaminidase (Endo-M). Through (1)H- and (13)C-NMR, DQF-COSY, HSQC, HMBC, TOCSY, and NOESY experiments, we determine the structure of the glycoside linkage formed by the Endo-M transglycosylation, i.e., the connection between GlcNAc and GlcNAc in oligosaccharide 1. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bioproduction of Chitooligosaccharides: Present and Perspectives
Jung, Woo-Jin; Park, Ro-Dong
2014-01-01
Chitin and chitosan oligosaccharides (COS) have been traditionally obtained by chemical digestion with strong acids. In light of the difficulties associated with these traditional production processes, environmentally compatible and reproducible production alternatives are desirable. Unlike chemical digestion, biodegradation of chitin and chitosan by enzymes or microorganisms does not require the use of toxic chemicals or excessive amounts of wastewater. Enzyme preparations with chitinase, chitosanase, and lysozymeare primarily used to hydrolyze chitin and chitosan. Commercial preparations of cellulase, protease, lipase, and pepsin provide another opportunity for oligosaccharide production. In addition to their hydrolytic activities, the transglycosylation activity of chitinolytic enzymes might be exploited for the synthesis of desired chitin oligomers and their derivatives. Chitin deacetylase is also potentially useful for the preparation of oligosaccharides. Recently, direct production of oligosaccharides from chitin and crab shells by a combination of mechanochemical grinding and enzymatic hydrolysis has been reported. Together with these, other emerging technologies such as direct degradation of chitin from crustacean shells and microbial cell walls, enzymatic synthesis of COS from small building blocks, and protein engineering technology for chitin-related enzymes have been discussed as the most significant challenge for industrial application. PMID:25353253
Fujimori, Miki; Kadota, Kazunori; Tozuka, Yuichi
2017-04-01
Transglycosylated stevia (stevia-G) can effectively improve the dissolution and bioavailability of poorly water-soluble drugs. Furthermore, addition of an ionic surfactant to stevia-G solution has been shown to enhance the dissolution effect of stevia-G on flurbiprofen. Herein, 4 surfactants, namely sodium dodecyl sulfate, sodium N-dodecanoylsarcosinate, sodium monododecyl phosphate, and lauryltrimethylammonium chloride (LTAC) were screened to investigate their synergistic effect with stevia-G in enhancing the solubility of mefenamic acid (MFA). The ternary formulation containing LTAC produced the highest increase in solubility, whereas the binary MFA/LTAC formulation did not increase the solubility of MFA. Surface tension was evaluated to analyze the interaction between stevia-G and each ionic surfactant, wherein the Rubingh model was applied to predict mixed micelle formation between stevia-G and LTAC. Interaction parameters calculated by the Rubingh model reflected mixed micelle formation between stevia-G and LTAC relative to the self-interactions of the 2 individual surfactants. All interaction parameters in this system showed negative values, indicating a favorable interaction (e.g., hydrogen bond or electrostatic and dipole) between binary components in the mixed micelles. Spray-dried particles of ternary formulations (MFA/stevia-G/LTAC) were prepared to evaluate the dissolution profile and physicochemical properties. Dissolution profiling showed that the concentration of MFA released from spray-dried particles was significantly higher than untreated MFA. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheng, Fang; Jia, Xiaofei; Yep, Alejandra
2009-07-06
Escherichia coli glycogen synthase (EcGS, EC 2.4.1.21) is a retaining glycosyltransferase (GT) that transfers glucose from adenosine diphosphate glucose to a glucan chain acceptor with retention of configuration at the anomeric carbon. EcGS belongs to the GT-B structural superfamily. Here we report several EcGS x-ray structures that together shed considerable light on the structure and function of these enzymes. The structure of the wild-type enzyme bound to ADP and glucose revealed a 15.2 degrees overall domain-domain closure and provided for the first time the structure of the catalytically active, closed conformation of a glycogen synthase. The main chain carbonyl groupmore » of His-161, Arg-300, and Lys-305 are suggested by the structure to act as critical catalytic residues in the transglycosylation. Glu-377, previously thought to be catalytic is found on the alpha-face of the glucose and plays an electrostatic role in the active site and as a glucose ring locator. This is also consistent with the structure of the EcGS(E377A)-ADP-HEPPSO complex where the glucose moiety is either absent or disordered in the active site« less
Lezyk, Mateusz; Jers, Carsten; Kjaerulff, Louise; Gotfredsen, Charlotte H.; Mikkelsen, Maria D.; Mikkelsen, Jørn D.
2016-01-01
This paper describes the discovery of novel α-L-fucosidases and evaluation of their potential to catalyse the transglycosylation reaction leading to production of fucosylated human milk oligosaccharides. Seven novel α-L-fucosidase-encoding genes were identified by functional screening of a soil-derived metagenome library and expressed in E. coli as recombinant 6xHis-tagged proteins. All seven fucosidases belong to glycosyl hydrolase family 29 (GH 29). Six of the seven α-L-fucosidases were substrate-inhibited, moderately thermostable and most hydrolytically active in the pH range 6–7, when tested with para-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) as the substrate. In contrast, one fucosidase (Mfuc6) exhibited a high pH optimum and an unusual sigmoidal kinetics towards pNP-Fuc substrate. When tested for trans-fucosylation activity using pNP-Fuc as donor, most of the enzymes were able to transfer fucose to pNP-Fuc (self-condensation) or to lactose. With the α-L-fucosidase from Thermotoga maritima and the metagenome-derived Mfuc5, different fucosyllactose variants including the principal fucosylated HMO 2’-fucosyllactose were synthesised in yields of up to ~6.4%. Mfuc5 was able to release fucose from xyloglucan and could also use it as a fucosyl-donor for synthesis of fucosyllactose. This is the first study describing the use of glycosyl hydrolases for the synthesis of genuine fucosylated human milk oligosaccharides. PMID:26800369
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imamura, Kayo; Matsuura, Takanori; Ye, Zhengmao
Disproportionating enzyme from potato was crystallized and preliminarily analyzed using X-ray diffraction. Disproportionating enzyme (D-enzyme; EC 2.4.1.25) is a 59 kDa protein that belongs to the α-amylase family. D-enzyme catalyses intramolecular and intermolecular transglycosylation reactions of α-1,4 glucan. A crystal of the D-enzyme from potato was obtained by the hanging-drop vapour-diffusion method. Preliminary X-ray data showed that the crystal diffracts to 2.0 Å resolution and belongs to space group C222{sub 1}, with unit-cell parameters a = 69.7, b = 120.3, c = 174.2 Å.
Li, Yonghao; Liu, Chenguang; Bai, Fengwu; Zhao, Xinqing
2016-09-01
Cellulase is a prerequisite for the bioconversion of lignocellulosic biomass, but its high cost presents the biggest challenge. In this article, low-cost mixture was produced from glucose through the transglycosylation reaction catalyzed by β-glucosidase for cellulase overproduction by Trichodema reesei RUT C30. As a result, cellulase titer of 90.3FPU/mL, which was more than 10 folds of that achieved with lactose as inducer, was achieved at 144h. Meanwhile, cellulase productivity was drastically increased to 627.1FPU/L/h, at least 3-5 folds higher than previously reported by the fungal species. The crude enzyme was further tested by hydrolyzing NaOH-pretreated corn stover with 15% solid loading, and 96.6g/L glucose was released with 92.6% sugar yield at 96h and 44.8g/L ethanol was obtained. Copyright © 2016 Elsevier Ltd. All rights reserved.
Nam, Seung-Hee; Ko, Jin-A; Jun, Woojin; Wee, Young-Jung; Walsh, Marie K; Yang, Kwang-Yeol; Choi, Jin-Ho; Eun, Jon-Bang; Choi, Jeong; Kim, Young-Min; Han, Songhee; Nguyen, Thi Thanh Hanh; Kim, Doman
2017-12-01
Chlorogenic acid, a major polyphenol in edible plants, possesses strong antioxidant activity, anti-lipid peroxidation and anticancer effects. It used for industrial applications; however, this is limited by its instability to heat or light. In this study, we for the first time synthesized chlorogenic acid glucoside (CHG) via transglycosylation using dextransucrase from Leuconostoc mesenteroides and sucrose. CHG was purified and its structure determined by nuclear magnetic resonance and matrix-associated laser desorption ionization-time-of-flight mass spectroscopy. The production yield of CHG was 44.0% or 141mM, as determined by response surface methodology. CHG possessed a 65% increased water solubility and 2-fold browning resistance while it displayed stronger inhibition of lipid peroxidation and of colon cancer cell growth by MTT assay, compared to chlorogenic acid. Therefore, this study may expand the industrial applications of chlorogenic acid as water-soluble or browning resistant compound (CHG) through enzymatic glycosylation. Copyright © 2017 Elsevier Inc. All rights reserved.
Braddick, Darren; Sandhu, Sandeep; Roper, David I; Chappell, Michael J; Bugg, Timothy D H
2014-08-01
The polymerization of lipid intermediate II by the transglycosylase activity of penicillin-binding proteins (PBPs) represents an important target for antibacterial action, but limited methods are available for quantitative assay of this reaction, or screening potential inhibitors. A new labelling method for lipid II polymerization products using Sanger's reagent (fluoro-2,4-dinitrobenzene), followed by gel permeation HPLC analysis, has permitted the observation of intermediate polymerization products for Staphylococcus aureus monofunctional transglycosylase MGT. Peak formation is inhibited by 6 µM ramoplanin or enduracidin. Characterization by mass spectrometry indicates the formation of tetrasaccharide and octasaccharide intermediates, but not a hexasaccharide intermediate, suggesting a dimerization of a lipid-linked tetrasaccharide. Numerical modelling of the time-course data supports a kinetic model involving addition to lipid-linked tetrasaccharide of either lipid II or lipid-linked tetrasaccharide. Observation of free octasaccharide suggests that hydrolysis of the undecaprenyl diphosphate lipid carrier occurs at this stage in peptidoglycan transglycosylation. © 2014 The Authors.
A novel member of glycoside hydrolase family 30 subfamily 8 with altered substrate specificity
St John, Franz J.; Dietrich, Diane; Crooks, Casey; Pozharski, Edwin; González, Javier M.; Bales, Elizabeth; Smith, Kennon; Hurlbert, Jason C.
2014-01-01
Endoxylanases classified into glycoside hydrolase family 30 subfamily 8 (GH30-8) are known to hydrolyze the hemicellulosic polysaccharide glucuronoxylan (GX) but not arabinoxylan or neutral xylooligosaccharides. This is owing to the specificity of these enzymes for the α-1,2-linked glucuronate (GA) appendage of GX. Limit hydrolysis of this substrate produces a series of aldouronates each containing a single GA substituted on the xylose penultimate to the reducing terminus. In this work, the structural and biochemical characterization of xylanase 30A from Clostridium papyrosolvens (CpXyn30A) is presented. This xylanase possesses a high degree of amino-acid identity to the canonical GH30-8 enzymes, but lacks the hallmark β8–α8 loop region which in part defines the function of this GH30 subfamily and its role in GA recognition. CpXyn30A is shown to have a similarly low activity on all xylan substrates, while hydrolysis of xylohexaose revealed a competing transglycosylation reaction. These findings are directly compared with the model GH30-8 enzyme from Bacillus subtilis, XynC. Despite its high sequence identity to the GH30-8 enzymes, CpXyn30A does not have any apparent specificity for the GA appendage. These findings confirm that the typically conserved β8–α8 loop region of these enzymes influences xylan substrate specificity but not necessarily β-1,4-xylanase function. PMID:25372685
van der Kaaij, R M; Yuan, X-L; Franken, A; Ram, A F J; Punt, P J; van der Maarel, M J E C; Dijkhuizen, L
2007-07-01
In the genome sequence of Aspergillus niger CBS 513.88, three genes were identified with high similarity to fungal alpha-amylases. The protein sequences derived from these genes were different in two ways from all described fungal alpha-amylases: they were predicted to be glycosylphosphatidylinositol anchored, and some highly conserved amino acids of enzymes in the alpha-amylase family were absent. We expressed two of these enzymes in a suitable A. niger strain and characterized the purified proteins. Both enzymes showed transglycosylation activity on donor substrates with alpha-(1,4)-glycosidic bonds and at least five anhydroglucose units. The enzymes, designated AgtA and AgtB, produced new alpha-(1,4)-glycosidic bonds and therefore belong to the group of the 4-alpha-glucanotransferases (EC 2.4.1.25). Their reaction products reached a degree of polymerization of at least 30. Maltose and larger maltooligosaccharides were the most efficient acceptor substrates, although AgtA also used small nigerooligosaccharides containing alpha-(1,3)-glycosidic bonds as acceptor substrate. An agtA knockout of A. niger showed an increased susceptibility towards the cell wall-disrupting compound calcofluor white, indicating a cell wall integrity defect in this strain. Homologues of AgtA and AgtB are present in other fungal species with alpha-glucans in their cell walls, but not in yeast species lacking cell wall alpha-glucan. Possible roles for these enzymes in the synthesis and/or maintenance of the fungal cell wall are discussed.
Ivanen, Dina R; Kulminskaya, Anna A; Shabalin, Konstantin A; Isaeva-Ivanova, Luydmila V; Ershova, Nadezhda A; Saveliev, Andrew N; Nevinsky, Gregory A; Neustroev, Kirill N
2004-08-01
Recently, amylolytic activity was detected in IgMs isolated from the sera of the patients with multiple sclerosis. All purified samples of IgM were electrophoretically homogenous and did not contain any co-purified a-amylase and a-glucosidase activities, in accordance with a set of criteria developed for abzymes. The amylolytic activity of abzymes was studied in the hydrolysis of p-nitrophenyl a-D-maltooligosaccharides with different degrees of polymerization from 1 to 8 by TLC and reverse-phase HPLC techniques. All IgM samples isolated from 54 patients with clinically definite multiple sclerosis demonstrated hydrolytic activity towards the above artificial substrates. The Michaelis constant values (Km) in the hydrolysis of p-nitrophenyl a-D-maltoheptaoside were in the range of 10 p-nitrophenyl or p-nitrophenyl a-D-glucosides, thus indicating the presence of an a-D-glucosidase activity. For a number of the investigated samples, specific amylolytic activity increased depending on the length of substrates (from p-nitrophenyl maltopentaoside to p-nitrophenyl maltohexaoside); for other IgMs, the opposite dependence was observed. All IgMs studied did not exhibit any other glycoside hydrolase activities toward p-nitrophenyl glycoside substrates. Abzyme fractions from different donors demonstrated catalytic heterogeneity in Michaelis-Menten parameters and different modes of action in the hydrolysis of p-nitrophenyl maltooligosaccharides. Enzymatic properties of the IgMs tested varied from human a-amylases. All investigated abzyme samples did not show transglycosylating ability.
Tomabechi, Yusuke; Katoh, Toshihiko; Kunishima, Munetaka; Inazu, Toshiyuki; Yamamoto, Kenji
2017-08-01
For chemo-enzymatic synthesis of a glycosylated peptide, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) was used for the synthesis of a N-acetylglucosaminyl peptide and a pseudoglycopeptide by solid-phase peptide synthesis without the requirement of protecting groups on the carbohydrate. We also performed transglycosylation of an N-glycan to the N-acetylglucosaminyl peptide using endo-β-N-acetylglucosaminidase from Mucor hiemalis (Endo-M) to synthesize a glycopeptide containing a complex N-glycan.
Wen, Chao; Huang, Wei; Zhu, Xue-Lin; Li, Xiao-San; Zhang, Fan; Jiang, Ren-Wang
2018-02-02
A permissive steroid glycosyltransferase (UGT74AN1) from Asclepias curassavica exhibited robust capabilities for the regiospecific C3 glycosylation of cardiotonic steroids and C 21 steroid precursors, and unprecedented promiscuity toward 53 structurally diverse natural and unnatural compounds to form O-, N-, and S-glycosides, along with the catalytic reversibility for a one-pot transglycosylation reaction. These findings highlight UGT74AN1 as the first regiospecific catalyst for cardiotonic steroid C3 glycosylation and exhibit significant potential for glycosylation of diverse bioactive molecules in drug discovery.
NASA Astrophysics Data System (ADS)
Shinohara, Naoki; Sunagawa, Naoki; Tamura, Satoru; Yokoyama, Ryusuke; Ueda, Minoru; Igarashi, Kiyohiko; Nishitani, Kazuhiko
2017-04-01
Cellulose is an economically important material, but routes of its industrial processing have not been fully explored. The plant cell wall - the major source of cellulose - harbours enzymes of the xyloglucan endotransglucosylase/hydrolase (XTH) family. This class of enzymes is unique in that it is capable of elongating polysaccharide chains without the requirement for activated nucleotide sugars (e.g., UDP-glucose) and in seamlessly splitting and reconnecting chains of xyloglucan, a naturally occurring soluble analogue of cellulose. Here, we show that a recombinant version of AtXTH3, a thus far uncharacterized member of the Arabidopsis XTH family, catalysed the transglycosylation between cellulose and cello-oligosaccharide, between cellulose and xyloglucan-oligosaccharide, and between xyloglucan and xyloglucan-oligosaccharide, with the highest reaction rate observed for the latter reaction. In addition, this enzyme formed cellulose-like insoluble material from a soluble cello-oligosaccharide in the absence of additional substrates. This newly found activity (designated “cellulose endotransglucosylase,” or CET) can potentially be involved in the formation of covalent linkages between cellulose microfibrils in the plant cell wall. It can also comprise a new route of industrial cellulose functionalization.
Weiss, Simon C.; Skerra, Arne; Schiefner, André
2015-01-01
Amylomaltase MalQ is essential for the metabolism of maltose and maltodextrins in Escherichia coli. It catalyzes transglycosylation/disproportionation reactions in which glycosyl or dextrinyl units are transferred among linear maltodextrins of various lengths. To elucidate the molecular basis of transglycosylation by MalQ, we have determined three crystal structures of this enzyme, i.e. the apo-form, its complex with maltose, and an inhibitor complex with the transition state analog acarviosine-glucose-acarbose, at resolutions down to 2.1 Å. MalQ represents the first example of a mesophilic bacterial amylomaltase with known structure and exhibits an N-terminal extension of about 140 residues, in contrast with previously described thermophilic enzymes. This moiety seems unique to amylomaltases from Enterobacteriaceae and folds into two distinct subdomains that associate with different parts of the catalytic core. Intriguingly, the three MalQ crystal structures appear to correspond to distinct states of this enzyme, revealing considerable conformational changes during the catalytic cycle. In particular, the inhibitor complex highlights the requirement of both a 3-OH group and a 4-OH group (or α1–4-glycosidic bond) at the acceptor subsite +1 for the catalytically competent orientation of the acid/base catalyst Glu-496. Using an HPLC-based MalQ enzyme assay, we could demonstrate that the equilibrium concentration of maltodextrin products depends on the length of the initial substrate; with increasing numbers of glycosidic bonds, less glucose is formed. Thus, both structural and enzymatic data are consistent with the extremely low hydrolysis rates observed for amylomaltases and underline the importance of MalQ for the metabolism of maltodextrins in E. coli. PMID:26139606
Yun, Eun Ju; Oh, Eun Joong; Liu, Jing-Jing; Yu, Sora; Kim, Dong Hyun; Kwak, Suryang; Kim, Kyoung Heon; Jin, Yong-Su
2018-01-01
Understanding the global metabolic network, significantly perturbed upon promiscuous activities of foreign enzymes and different carbon sources, is crucial for systematic optimization of metabolic engineering of yeast Saccharomyces cerevisiae . Here, we studied the effects of promiscuous activities of overexpressed enzymes encoded by foreign genes on rerouting of metabolic fluxes of an engineered yeast capable of assimilating sugars from renewable biomass by profiling intracellular and extracellular metabolites. Unbiased metabolite profiling of the engineered S. cerevisiae strain EJ4 revealed promiscuous enzymatic activities of xylose reductase and xylitol dehydrogenase on galactose and galactitol, respectively, resulting in accumulation of galactitol and tagatose during galactose fermentation. Moreover, during glucose fermentation, a trisaccharide consisting of glucose accumulated outside of the cells probably owing to the promiscuous and transglycosylation activity of β-glucosidase expressed for hydrolyzing cellobiose. Meanwhile, higher accumulation of fatty acids and secondary metabolites was observed during xylose and cellobiose fermentations, respectively. The heterologous enzymes functionally expressed in S. cerevisiae showed promiscuous activities that led to unintended metabolic rerouting in strain EJ4. Such metabolic rerouting could result in a low yield and productivity of a final product due to the formation of unexpected metabolites. Furthermore, the global metabolic network can be significantly regulated by carbon sources, thus yielding different patterns of metabolite production. This metabolomic study can provide useful information for yeast strain improvement and systematic optimization of yeast metabolism to manufacture bio-based products.
Ahn, Hee-Jeong; Li, Chao; Cho, Hye-Bin; Park, Sunghoon; Chang, Pahn-Shick; Kim, Young-Wan
2015-02-15
A mutant derived from a cyclodextrin glucantransferase with an alanine residue as its acid/base catalyst residue (CGT-E284A) catalyzed regioselective glycosylation at 3-OH of l-ascorbic acid using α-maltosyl fluoride (αG2F) and l-ascorbic acid as the donor and acceptor, respectively, yielding 3-O-α-maltosyl-l-ascorbate (AA3αG2). The optimum conditions were determined by high-performance liquid chromatography analysis with 20mM αG2F and 40mM l-ascorbic acid as the substrates at pH 7.5 and 25°C with 1mg/ml of the enzyme for 24h. Calcium ions bound in CGT-E284A played an important role in the transglycosylation. CGT-E284A exhibited typical saturation kinetic behaviour for αG2F at a fixed acceptor concentration (40mM), and substrate inhibition by l-ascorbic acid was observed at high l-ascorbic acid concentrations (>60mM). AA3αG2 was isolated from a preparative scale reaction with a yield of 29%, and it showed extremely high stability under oxidative conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Three-dimensional structure of E. Coli purine nucleoside phosphorylase at 0.99 Å resolution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timofeev, V. I., E-mail: tostars@mail.ru; Abramchik, Yu. A., E-mail: ugama@yandex.ru; Zhukhlistova, N. E., E-mail: inna@ns.crys.ras.ru
2016-03-15
Purine nucleoside phosphorylases (PNPs) catalyze the reversible phosphorolysis of nucleosides and are key enzymes involved in nucleotide metabolism. They are essential for normal cell function and can catalyze the transglycosylation. Crystals of E. coli PNP were grown in microgravity by the capillary counterdiffusion method through a gel layer. The three-dimensional structure of the enzyme was determined by the molecular-replacement method at 0.99 Å resolution. The structural features are considered, and the structure of E. coli PNP is compared with the structures of the free enzyme and its complexes with purine base derivatives established earlier. A comparison of the environment ofmore » the purine base in the complex of PNP with formycin A and of the pyrimidine base in the complex of uridine phosphorylase with thymidine revealed the main structural features of the base-binding sites. Coordinates of the atomic model determined with high accuracy were deposited in the Protein Data Bank (PDB-ID: 4RJ2).« less
Niu, Xin; Zhou, Jiang-Sheng; Wang, Yan-Xin; Liu, Cui-Cui; Liu, Zhong-Hua; Yuan, Sheng
2017-08-16
Chitinase ChiEn1 did not hydrolyze insoluble chitin but showed hydrolysis and transglycosylation activities toward chitin-oligosaccharides. Interestingly, the addition of ChiEn1 increased the amount of reducing sugars released from chitin powder by endochitinase ChiIII by 105.0%, and among the released reducing sugars the amount of (GlcNAc) 2 was increased by 149.5%, whereas the amount of GlcNAc was decreased by 10.3%. The percentage of GlcNAc in the products of chitin powder with the combined ChiIII and ChiEn1 was close to that in the products of chitin-oligosaccharides with ChiEn1, rather than that with ChiIII. These results indicate that chitin polymers are first degraded into chitin oligosaccharides by ChiIII and the latter are further degraded to monomers and dimers by ChiEn1, and the synergistic action of ChiEn1 and ChiIII is involved in the efficient degradation of chitin in cell walls during pileus autolysis. The structure modeling explores the molecular base of ChiEn1 action.
Kieser, Karen J.; Baer, Christina E.; Barczak, Amy K.; Meniche, Xavier; Chao, Michael C.; Rego, E. Hesper; Sassetti, Christopher M.; Fortune, Sarah M.; Rubin, Eric J.
2015-01-01
Cell growth and division are required for the progression of bacterial infections. Most rod-shaped bacteria grow by inserting new cell wall along their mid-section. However, mycobacteria, including the human pathogen Mycobacterium tuberculosis, produce new cell wall material at their poles. How mycobacteria control this different mode of growth is incompletely understood. Here we find that PonA1, a penicillin binding protein (PBP) capable of transglycosylation and transpeptidation of cell wall peptidoglycan (PG), is a major governor of polar growth in mycobacteria. PonA1 is required for growth of Mycobacterium smegmatis and is critical for M. tuberculosis during infection. In both cases, PonA1’s catalytic activities are both required for normal cell length, though loss of transglycosylase activity has a more pronounced effect than transpeptidation. Mutations that alter the amount or the activity of PonA1 result in abnormal formation of cell poles and changes in cell length. Moreover, altered PonA1 activity results in dramatic differences in antibiotic susceptibility, suggesting that a balance between the two enzymatic activities of PonA1 is critical for survival. We also find that phosphorylation of a cytoplasmic region of PonA1 is required for normal activity. Mutations in a critical phosphorylated residue affect transglycosylase activity and result in abnormal rates of cell elongation. Together, our data indicate that PonA1 is a central determinant of polar growth in mycobacteria, and its governance of cell elongation is required for robust cell fitness during both host-induced and antibiotic stress. PMID:26114871
Bause, E; Wesemann, M; Bartoschek, A; Breuer, W
1997-02-15
Pig liver oligosaccharyltransferase (OST) is inactivated irreversibly by a hexapeptide in which threonine has been substituted by epoxyethylglycine in the Asn-Xaa-Thr glycosylation triplet. Incubation of the enzyme in the presence of Dol-PP-linked [14C]oligosaccharides and the N-3,5-dinitrobenzoylated epoxy derivative leads to the double-labelling of two subunits (48 and 66 kDa) of the oligomeric OST complex, both of which are involved in the catalytic activity. Labelling of both subunits was blocked competitively by the acceptor peptide N-benzoyl-Asu-Gly-Thr-NHCH3 and by the OST inhibitor N-benzoyl-alpha,gamma-diaminobutyric acid-Gly-Thr-NHCH3, but not by an analogue derived from the epoxy-inhibitor by replacing asparagine with glutamine. Our data clearly show that double-labelling is an active-site-directed modification, involving inhibitor glycosylation at asparagine and covalent attachment of the glycosylated inhibitor, via the epoxy group, to the enzyme. Double-labelling of OST can occur as the result of either a consecutive or a syn-catalytic reaction sequence. The latter mechanism, during the course of which OST catalyses its own 'suicide' inactivation, is more likely, as suggested by indirect experimental evidence. The syn-catalytic mechanism corresponds with our current view of the functional role of the acceptor site Thr/Ser acting as a hydrogen-bond acceptor, not a donor, during transglycosylation.
Sialidases from gut bacteria: a mini-review.
Juge, Nathalie; Tailford, Louise; Owen, C David
2016-02-01
Sialidases are a large group of enzymes, the majority of which catalyses the cleavage of terminal sialic acids from complex carbohydrates on glycoproteins or glycolipids. In the gastrointestinal (GI) tract, sialic acid residues are mostly found in terminal location of mucins via α2-3/6 glycosidic linkages. Many enteric commensal and pathogenic bacteria can utilize sialic acids as a nutrient source, but not all express the sialidases that are required to release free sialic acid. Sialidases encoded by gut bacteria vary in terms of their substrate specificity and their enzymatic reaction. Most are hydrolytic sialidases, which release free sialic acid from sialylated substrates. However, there are also examples with transglycosylation activities. Recently, a third class of sialidases, intramolecular trans-sialidase (IT-sialidase), has been discovered in gut microbiota, releasing (2,7-anhydro-Neu5Ac) 2,7-anydro-N-acetylneuraminic acid instead of sialic acid. Reaction specificity varies, with hydrolytic sialidases demonstrating broad activity against α2,3-, α2,6- and α2,8-linked substrates, whereas IT-sialidases tend to be specific for α2,3-linked substrates. In this mini-review, we summarize the current knowledge on the structural and biochemical properties of sialidases involved in the interaction between gut bacteria and epithelial surfaces. © 2016 Authors.
Katrolia, Priti; Yan, Qiaojuan; Zhang, Pan; Zhou, Peng; Yang, Shaoqing; Jiang, Zhengqiang
2013-01-16
An endo-1,4-β-mannanase gene (RmMan5A) was cloned from the thermophilic fungus Rhizomucor miehei for the first time and expressed in Escherichia coli . The gene had an open reading frame of 1330 bp encoding 378 amino acids and contained four introns. It displayed the highest amino acid sequence identity (42%) with the endo-1,4-β-mannanases from glycoside hydrolase family 5. The purified enzyme was a monomer of 43 kDa. RmMan5A displayed maximum activity at 55 °C and an optimal pH of 7.0. It was thermostable up to 55 °C and alkali-tolerant, displaying excellent stability over a broad pH range of 4.0-10.0, when incubated for 30 min without substrate. The enzyme displayed the highest specificity for locust bean gum (K(m) = 3.78 mg mL⁻¹), followed by guar gum (K(m) = 7.75 mg mL⁻¹) and konjac powder (K(m) = 22.7 mg mL⁻¹). RmMan5A hydrolyzed locust bean gum and konjac powder yielding mannobiose, mannotriose, and a mixture of various mannose-linked oligosaccharides. It was confirmed to be a true endo-acting β-1,4-mannanase, which showed requirement of four mannose residues for hydrolysis, and was also capable of catalyzing transglycosylation reactions. These properties make RmMan5A highly useful in the food/feed, paper and pulp, and detergent industries.
Li, Xiaolei; Fei, Teng; Wang, Yong; Zhao, Yakun; Pan, Yutian; Li, Dan
2018-04-18
A GtfB enzyme 4,6-α-glucanotransferase from Streptococcus thermophilus lacking 761 N-terminal amino acids was heterologously expressed in Escherichia coli. Purified S. thermophilus GtfB showed transglycosylation activities toward starch, resulting in branch points of (α1→6)-glycosidic linkages plus linear chains of (α1→4)-glycosidic linkages. After wheat starch was modified at a rate of 0.1 g/mL by 1-4 U/g starch GtfB at pH 6.0 and 40 °C for 1 h, the weight-averaged molecular weight decreased from 1.70 × 10 7 g/mol to 1.21 × 10 6 to 3.41 × 10 6 g/mol, the amylose content decreased from 22.07 to 16.34-17.11%, and that of amylopectin long-branch chains decreased from 26.4 to 10.25-15.64% ( P < 0.05). After the GtfB-modified wheat starches were gelatinized and stored at 4 °C for 1-2 weeks, their endothermic enthalpies were significantly lower than that of the control sample ( P < 0.05), indicating low retrogradation rates.
Bai, Yuxiang; Gangoiti, Joana; Dijkstra, Bauke W; Dijkhuizen, Lubbert; Pijning, Tjaard
2017-02-07
Food processing and refining has dramatically changed the human diet, but little is known about whether this affected the evolution of enzymes in human microbiota. We present evidence that glycoside hydrolase family 70 (GH70) glucansucrases from lactobacilli, synthesizing α-glucan-type extracellular polysaccharides from sucrose, likely evolved from GH13 starch-acting α-amylases, via GH70 4,6-α-glucanotransferases. The crystal structure of a 4,6-α-glucanotransferase explains the mode of action and unique product specificity of these enzymes. While the α-amylase substrate-binding scaffold is retained, active-site loops adapted to favor transglycosylation over hydrolysis; the structure also gives clues as to how 4,6-α-glucanotransferases may have evolved further toward sucrose utilization instead of starch. Further supported by genomic, phylogenetic, and in vivo studies, we propose that dietary changes involving starch (and starch derivatives) and sucrose intake were critical factors during the evolution of 4,6-α-GTs and glucansucrases from α-amylases, allowing oral bacteria to produce extracellular polymers that contribute to biofilm formation from different substrates. Copyright © 2017 Elsevier Ltd. All rights reserved.
Gutiérrez-Alonso, Patricia; Gimeno-Pérez, María; Ramírez-Escudero, Mercedes; Plou, Francisco J; Sanz-Aparicio, Julia; Fernández-Lobato, María
2016-04-01
Basidiomycetous yeast Xanthophyllomyces dendrorhous expresses an α-glucosidase with strong transglycosylation activity producing prebiotic sugars such as panose and an unusual tetrasaccharides mixture including α-(1-6) bonds as major products, which makes it of biotechnological interest. Initial analysis pointed to a homodimeric protein of 60 kDa subunit as responsible for this activity. In this study, the gene Xd-AlphaGlu was characterized. The 4131-bp-long gene is interrupted by 13 short introns and encodes a protein of 990 amino acids (Xd-AlphaGlu). The N-terminal sequence of the previously detected 60 kDa protein resides in this larger protein at residues 583-602. Functionality of the gene was proved in Saccharomyces cerevisiae, which produced a protein of about 130 kDa containing Xd-AlphaGlu sequences. All properties of the heterologously expressed protein, including thermal and pH profiles, activity on different substrates, and ability to produce prebiotic sugars were similar to that of the α-glucosidase produced in X. dendrorhous. No activity was detected in S. cerevisiae containing exclusively the 1256-bp from gene Xd-AlphaGlu that would encode synthesis of the 60 kDa protein previously detected. Data were compatible with an active monomeric α-glucosidase of 990 amino acids and an inactive hydrolysis product of 60 kDa. Protein Xd-AlphaGlu contained most of the elements characteristic of α-glucosidases included in the glycoside hydrolases family GH31 and its structural model based on the homologous human maltase-glucoamylase was obtained. Remarkably, the Xd-AlphaGlu C-terminal domain presents an unusually long 115-residue insertion that could be involved in this enzyme's activity against long-size substrates such as maltoheptaose and soluble starch.
Mazáň, Marián; Ragni, Enrico; Popolo, Laura; Farkaš, Vladimír
2011-09-01
BGTs [β-(1,3)-glucanosyltransglycosylases; EC 2.4.1.-] of the GH72 (family 72 of glycosylhydrolases) are GPI (glycosylphosphatidylinositol)-anchored proteins that play an important role in the biogenesis of fungal cell walls. They randomly cleave glycosidic linkages in β-(1,3)-glucan chains and ligate the polysaccharide portions containing newly formed reducing ends to C(3)(OH) at non-reducing ends of other β-(1,3)-glucan molecules. We have developed a sensitive fluorescence-based method for the assay of transglycosylating activity of GH72 enzymes. In the new assay, laminarin [β-(1,3)-glucan] is used as the glucanosyl donor and LamOS (laminarioligosaccharides) fluorescently labelled with SR (sulforhodamine) serve as the acceptors. The new fluorescent assay was employed for partial biochemical characterization of the heterologously expressed Gas family proteins from the yeast Saccharomyces cerevisiae. All the Gas enzymes specifically used laminarin as the glucanosyl donor and a SR-LamOS of DP (degree of polymerization) ≥5 as the acceptors. Gas proteins expressed in distinct stages of the yeast life cycle showed differences in their pH optima. Gas1p and Gas5p, which are expressed during vegetative growth, had the highest activity at pH 4.5 and 3.5 respectively, whereas the sporulation-specific Gas2p and Gas4p were most active between pH 5 and 6. The novel fluorescent assay provides a suitable tool for the screening of potential glucanosyltransferases or their inhibitors.
Sass, Peter; Jansen, Andrea; Szekat, Christiane; Sass, Vera; Sahl, Hans-Georg; Bierbaum, Gabriele
2008-01-01
Background The lantibiotic mersacidin is an antimicrobial peptide of 20 amino acids that is ribosomally produced by Bacillus sp. strain HIL Y-85,54728. Mersacidin acts by complexing the sugar phosphate head group of the peptidoglycan precursor lipid II, thereby inhibiting the transglycosylation reaction of peptidoglycan biosynthesis. Results Here, we studied the growth of Staphylococcus aureus in the presence of subinhibitory concentrations of mersacidin. Transcriptional data revealed an extensive induction of the cell wall stress response, which is partly controlled by the two-component regulatory system VraSR. In contrast to other cell wall-active antibiotics such as vancomycin, very low concentrations of mersacidin (0.15 × MIC) were sufficient for induction. Interestingly, the cell wall stress response was equally induced in vancomycin intermediately resistant S. aureus (VISA) and in a highly susceptible strain. Since the transcription of the VraDE ABC transporter genes was induced up to 1700-fold in our experiments, we analyzed the role of VraDE in the response to mersacidin. However, the deletion of the vraE gene did not result in an increased susceptibility to mersacidin compared to the wild type strain. Moreover, the efficacy of mersacidin was not affected by an increased cell wall thickness, which is part of the VISA-type resistance mechanism and functions by trapping the vancomycin molecules in the cell wall before they reach lipid II. Therefore, the relatively higher concentration of mersacidin at the membrane might explain why mersacidin is such a strong inducer of VraSR compared to vancomycin. Conclusion In conclusion, mersacidin appears to be a strong inducer of the cell wall stress response of S. aureus at very low concentrations, which reflects its general mode of action as a cell wall-active peptide as well as its use of a unique target site on lipid II. Additionally, mersacidin does not seem to be a substrate for the resistance transporter VraDE. PMID:18947397
Xue, Xianli; Wu, Yilan; Qin, Xing; Ma, Rui; Luo, Huiying; Su, Xiaoyun; Yao, Bin
2016-07-11
The filamentous fungus Trichoderma reesei has the capacity to secret large amounts of cellulase and is widely used in a variety of industries. However, the T. reesei cellulase is weak in β-glucosidase activity, which results in accumulation of cellobiose inhibiting the endo- and exo-cellulases. By expressing an exogenous β-glucosidase gene, the recombinant T. reesei cellulase is expected to degrade cellulose into glucose more efficiently. The thermophilic β-glucosidase NfBgl3A from Neosartorya fischeri is chosen for overexpression in T. reesei due to its robust activity. In vitro, the Pichia pastoris-expressed NfBgl3A aided the T. reesei cellulase in releasing much more glucose with significantly lower amounts of cellobiose from crystalline cellulose. The NfBgl3A gene was hence fused to the cbh1 structural gene and assembled between the strong cbh1 promoter and cbh1 terminator to obtain pRS-NfBgl3A by using the DNA assembler method. pRS-NfBgl3A was transformed into the T. reesei uridine auxotroph strain TU-6. Six positive transformants showed β-glucosidase activities of 2.3-69.7 U/mL (up to 175-fold higher than that of wild-type). The largely different β-glucosidase activities in the transformants may be ascribed to the gene copy numbers of NfBgl3A or its integration loci. The T. reesei-expressed NfBgl3A showed highly similar biochemical properties to that expressed in P. pastoris. As expected, overexpression of NfBgl3A enhanced the overall cellulase activity of T. reesei. The CBHI activity in all transformants increased, possibly due to the extra copies of cbh1 gene introduced, while the endoglucanase activity in three transformants also largely increased, which was not observed in any other studies overexpressing a β-glucosidase. NfBgl3A had significant transglycosylation activity, generating sophorose, a potent cellulase inducer, and other oligosaccharides from glucose and cellobiose. We report herein the successful overexpression of a thermophilic N. fischeri β-glucosidase in T. reesei. In the same time, the fusion of NfBgl3A to the cbh1 gene introduced extra copies of the cellobiohydrolase 1 gene. As a result, we observed improved β-glucosidase and cellobiohydrolase activity as well as the overall cellulase activity. In addition, the endoglucanase activity also increased in some of the transformants. Our results may shed light on design of more robust T. reesei cellulases.
Ruprecht, Colin; Dallabernardina, Pietro; Smith, Peter J; Urbanowicz, Breeanna R; Pfrengle, Fabian
2018-04-16
The plant cell wall is a cellular exoskeleton consisting predominantly of a complex polysaccharide network that defines the shape of cells. During growth, this network can be loosened through the action of xyloglucan endotransglycosylases (XETs), glycoside hydrolases that "cut and paste" xyloglucan polysaccharides through a transglycosylation process. We have analyzed cohorts of XETs in different plant species to evaluate the substrate specificities of xyloglucan acceptors by using a set of synthetic oligosaccharides obtained by automated glycan assembly. The ability of XETs to incorporate the oligosaccharides into polysaccharides printed as microarrays and into stem sections of Arabidopsis thaliana, beans, and peas was assessed. We found that single xylose substitutions are sufficient for transfer, and xylosylation of the terminal glucose residue is not required by XETs, independent of plant species. To obtain information on the potential xylosylation pattern of the natural acceptor of XETs, that is, the nonreducing end of xyloglucan, we further tested the activity of xyloglucan xylosyl transferase (XXT) 2 on the synthetic xyloglucan oligosaccharides. These data shed light on inconsistencies between previous studies towards determining the acceptor substrate specificities of XETs and have important implications for further understanding plant cell wall polysaccharide synthesis and remodeling. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Shigeyama, Takuma; Watanabe, Asuka; Tokuchi, Konatsu; Toh, Shigeo; Sakurai, Naoki; Shibuya, Naoto; Kawakami, Naoto
2016-01-01
Regulation and maintenance of cell wall physical properties are crucial for plant growth and environmental response. In the germination process, hypocotyl cell expansion and endosperm weakening are prerequisites for dicot seeds to complete germination. We have identified the Arabidopsis mutant thermoinhibition-resistant germination 1 (trg1), which has reduced seed dormancy and insensitivity to unfavourable conditions for germination owing to a loss-of-function mutation of TRG1/XYL1, which encodes an α-xylosidase. Compared to those of wild type, the elongating stem of trg1 showed significantly lower viscoelasticity, and the fruit epidermal cells were longitudinally shorter and horizontally enlarged. Actively growing tissues of trg1 over-accumulated free xyloglucan oligosaccharides (XGOs), and the seed cell wall had xyloglucan with a greatly reduced molecular weight. These observations suggest that XGOs reduce xyloglucan size by serving as an acceptor in transglycosylation and eventually enhancing cell wall loosening. TRG1/XYL1 gene expression was abundant in growing wild-type organs and tissues but relatively low in cells at most actively elongating part of the tissues, suggesting that α-xylosidase contributes to maintaining the mechanical integrity of the primary cell wall in the growing and pre-growing tissues. In germinating seeds of trg1, expression of genes encoding specific abscisic acid and gibberellin metabolism enzymes was altered in accordance with the aberrant germination phenotype. Thus, cell wall integrity could affect seed germination not only directly through the physical properties of the cell wall but also indirectly through the regulation of hormone gene expression. PMID:27605715
Linde, Dolores; Macias, Isabel; Fernández-Arrojo, Lucía; Plou, Francisco J.; Jiménez, Antonio; Fernández-Lobato, María
2009-01-01
An extracellular β-fructofuranosidase from the yeast Xanthophyllomyces dendrorhous was characterized biochemically, molecularly, and phylogenetically. This enzyme is a glycoprotein with an estimated molecular mass of 160 kDa, of which the N-linked carbohydrate accounts for 60% of the total mass. It displays optimum activity at pH 5.0 to 6.5, and its thermophilicity (with maximum activity at 65 to 70°C) and thermostability (with a T50 in the range 66 to 71°C) is higher than that exhibited by most yeast invertases. The enzyme was able to hydrolyze fructosyl-β-(2→1)-linked carbohydrates such as sucrose, 1-kestose, or nystose, although its catalytic efficiency, defined by the kcat/Km ratio, indicates that it hydrolyzes sucrose approximately 4.2 times more efficiently than 1-kestose. Unlike other microbial β-fructofuranosidases, the enzyme from X. dendrorhous produces neokestose as the main transglycosylation product, a potentially novel bifidogenic trisaccharide. Using a 41% (wt/vol) sucrose solution, the maximum fructooligosaccharide concentration reached was 65.9 g liter−1. In addition, we isolated and sequenced the X. dendrorhous β-fructofuranosidase gene (Xd-INV), showing that it encodes a putative mature polypeptide of 595 amino acids and that it shares significant identity with other fungal, yeast, and plant β-fructofuranosidases, all members of family 32 of the glycosyl-hydrolases. We demonstrate that the Xd-INV could functionally complement the suc2 mutation of Saccharomyces cerevisiae and, finally, a structural model of the new enzyme based on the homologous invertase from Arabidopsis thaliana has also been obtained. PMID:19088319
Konishi, Masa-aki; Fukuoka, Tokuma; Shimane, Yasuhiro; Mori, Kozue; Nagano, Yuriko; Ohta, Yukari; Kitamoto, Dai; Hatada, Yuji
2011-01-01
To explore a novel glycolipid, we performed biochemical reactions using a recombinant α-glucosidase from Geobacillus sp. which shows excellent transglycosylation reaction to hydroxyl groups in a variety of compounds. Two different glycolipids (GL-1 and GL-2) were prepared from ricinoleic acid using a recombinant α-glucosidase from Geobacillus sp. The molecular structure of GL-1 was confirmed as 12-O-α-D-glucopyranosyl-9-hexadecenoic acid by 1D and 2D NMR analyses. According to MALDI-TOF/MS, GL-1 and GL-2 showed single major peaks at m/z 483.82 and 645.97, respectively. The peaks corresponded to the [M + Na](+) ions of the glycolipids. GL-2 was estimated as 12-O-α-D-glucopyranosyl-(4'-O-α-glucopyranosyl)-9-hexadecenoic acid. Light polarization microscopy revealed that GL-2 easily formed self-assembled vesicles in aqueous solution.
Lu, Lili; Xu, Lijuan; Guo, Yuchuan; Zhang, Dayu; Qi, Tingting; Jin, Lan; Gu, Guofeng; Xu, Li; Xiao, Min
2015-01-01
β-Galactosidases can transfer the galactosyl from lactose or galactoside donors to various acceptors and thus are especially useful for the synthesis of important glycosides. However, these enzymes have limitations in the glycosylation of phenolic compounds that have many physiological functions. In this work, the β-galactosidase from Lactobacillus bulgaricus L3 was subjected to site-saturation mutagenesis at the W980 residue. The recombinant pET-21b plasmid carrying the enzyme gene was used as the template for mutation. The mutant plasmids were transformed into Escherichia coli cells for screening. One recombinant mutant, W980F, exhibited increased yield of glycoside when using hydroquinone as the screening acceptor. The enzyme was purified and the effects of the mutation on enzyme properties were determined in detail. It showed improved transglycosylation activity on novel phenolic acceptors besides hydroquinone. The yields of the glycosides produced from phenol, hydroquinone, and catechol were increased by 7.6% to 53.1%. Moreover, it generated 32.3% glycosides from the pyrogallol that could not be glycosylated by the wild-type enzyme. Chemical structures of these glycoside products were further determined by MS and NMR analysis. Thus, a series of novel phenolic galactosides were achieved by β-galactosidase for the first time. This was a breakthrough in the enzymatic galactosylation of the challenging phenolic compounds of great values.
Couturier, Marie; Roussel, Alain; Rosengren, Anna; Leone, Philippe; Stålbrand, Henrik; Berrin, Jean-Guy
2013-01-01
The microbial deconstruction of the plant cell wall is a key biological process that is of increasing importance with the development of a sustainable biofuel industry. The glycoside hydrolase families GH5 (PaMan5A) and GH26 (PaMan26A) endo-β-1,4-mannanases from the coprophilic ascomycete Podospora anserina contribute to the enzymatic degradation of lignocellulosic biomass. In this study, P. anserina mannanases were further subjected to detailed comparative analysis of their substrate specificities, active site organization, and transglycosylation capacity. Although PaMan5A displays a classical mode of action, PaMan26A revealed an atypical hydrolysis pattern with the release of mannotetraose and mannose from mannopentaose resulting from a predominant binding mode involving the −4 subsite. The crystal structures of PaMan5A and PaMan26A were solved at 1.4 and 2.85 Å resolution, respectively. Analysis of the PaMan26A structure supported strong interaction with substrate at the −4 subsite mediated by two aromatic residues Trp-244 and Trp-245. The PaMan26A structure appended to its family 35 carbohydrate binding module revealed a short and proline-rich rigid linker that anchored together the catalytic and the binding modules. PMID:23558681
Genetic and biochemical characterization of an oligo-α-1,6-glucosidase from Lactobacillus plantarum.
Delgado, Susana; Flórez, Ana Belén; Guadamuro, Lucía; Mayo, Baltasar
2017-04-04
Although encoded in the genome of many Lactobacillus spp. strains, α-glucosidases have received little attention compared to other glycosyl hydrolases. In this study, a putative oligosaccharide(oligo)-α-1,6-glucosidase-encoding gene (malL) was identified in the genome of Lactobacillus plantarum LL441. malL coded for 572 amino acid residues with a calculated total molecular mass of 66.31kDa. No predicted signal peptide was observed, suggesting this enzyme to be localized within the cytoplasm of the cell. Homology studies of the deduced amino acid sequence in the area of its active sites classified the enzyme as a member of the α-amylase (AmyAC) superfamily of glycosyl hydrolases (GH), family 13 (GH13), subfamily 31 (GH13_31). malL was cloned in Escherichia coli and the coded enzyme overexpressed as a histidine-tagged protein (MalL His ). It was then purified and characterized. MalL His protein showed strong hydrolytic activity towards 4-nitrophenyl-α-d-glucopyranoside (pNP-α-Glu) but not to other pNP-α-d- or pNP-β-d-derivatives. When using pNP-α-Glu as a substrate, MalL His showed similar specific activities between pH5.0 and 6.0, and between 20 and 42°C (optimum 30°C). Among the natural carbohydrates assayed, MalL His showed specificity towards isomaltose (V max and K m values of 40.64μmolmin -1 mg -1 and 6.22mM) and much less to isomaltulose (V max and K m values of 168.86μmolmin -1 mg -1 and 244.52mM). However, under the conditions of the assay, the enzyme showed no transglycosylation activity. Characterization of the entire complement of glycosidases in L. plantarum might reveal how strains of this species could be used in new biotechnological applications or in the development of functional foods. Copyright © 2017 Elsevier B.V. All rights reserved.
Shigeyama, Takuma; Watanabe, Asuka; Tokuchi, Konatsu; Toh, Shigeo; Sakurai, Naoki; Shibuya, Naoto; Kawakami, Naoto
2016-10-01
Regulation and maintenance of cell wall physical properties are crucial for plant growth and environmental response. In the germination process, hypocotyl cell expansion and endosperm weakening are prerequisites for dicot seeds to complete germination. We have identified the Arabidopsis mutant thermoinhibition-resistant germination 1 (trg1), which has reduced seed dormancy and insensitivity to unfavourable conditions for germination owing to a loss-of-function mutation of TRG1/XYL1, which encodes an α-xylosidase. Compared to those of wild type, the elongating stem of trg1 showed significantly lower viscoelasticity, and the fruit epidermal cells were longitudinally shorter and horizontally enlarged. Actively growing tissues of trg1 over-accumulated free xyloglucan oligosaccharides (XGOs), and the seed cell wall had xyloglucan with a greatly reduced molecular weight. These observations suggest that XGOs reduce xyloglucan size by serving as an acceptor in transglycosylation and eventually enhancing cell wall loosening. TRG1/XYL1 gene expression was abundant in growing wild-type organs and tissues but relatively low in cells at most actively elongating part of the tissues, suggesting that α-xylosidase contributes to maintaining the mechanical integrity of the primary cell wall in the growing and pre-growing tissues. In germinating seeds of trg1, expression of genes encoding specific abscisic acid and gibberellin metabolism enzymes was altered in accordance with the aberrant germination phenotype. Thus, cell wall integrity could affect seed germination not only directly through the physical properties of the cell wall but also indirectly through the regulation of hormone gene expression. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Zhou, Qingxin; Xu, Jintao; Kou, Yanbo; Lv, Xinxing; Zhang, Xi; Zhao, Guolei; Zhang, Weixin; Chen, Guanjun
2012-01-01
Appropriate perception of cellulose outside the cell by transforming it into an intracellular signal ensures the rapid production of cellulases by cellulolytic Hypocrea jecorina. The major extracellular β-glucosidase BglI (CEL3a) has been shown to contribute to the efficient induction of cellulase genes. Multiple β-glucosidases belonging to glycosyl hydrolase (GH) family 3 and 1, however, exist in H. jecorina. Here we demonstrated that CEL1b, like CEL1a, was an intracellular β-glucosidase displaying in vitro transglycosylation activity. We then found evidence that these two major intracellular β-glucosidases were involved in the rapid induction of cellulase genes by insoluble cellulose. Deletion of cel1a and cel1b significantly compromised the efficient gene expression of the major cellulase gene, cbh1. Simultaneous absence of BglI, CEL1a, and CEL1b caused the induction of the cellulase gene by cellulose to further deteriorate. The induction defect, however, was not observed with cellobiose. The absence of the three β-glucosidases, rather, facilitated the induced synthesis of cellulase on cellobiose. Furthermore, addition of cellobiose restored the productive induction on cellulose in the deletion strains. The results indicate that the three β-glucosidases may not participate in transforming cellobiose beyond hydrolysis to provoke cellulase formation in H. jecorina. They may otherwise contribute to the accumulation of cellobiose from cellulose as inducing signals. PMID:23002106
The Bacillus subtilis GntR family repressor YtrA responds to cell wall antibiotics.
Salzberg, Letal I; Luo, Yun; Hachmann, Anna-Barbara; Mascher, Thorsten; Helmann, John D
2011-10-01
The transglycosylation step of cell wall synthesis is a prime antibiotic target because it is essential and specific to bacteria. Two antibiotics, ramoplanin and moenomycin, target this step by binding to the substrate lipid II and the transglycosylase enzyme, respectively. Here, we compare the ramoplanin and moenomycin stimulons in the Gram-positive model organism Bacillus subtilis. Ramoplanin strongly induces the LiaRS two-component regulatory system, while moenomycin almost exclusively induces genes that are part of the regulon of the extracytoplasmic function (ECF) σ factor σ(M). Ramoplanin additionally induces the ytrABCDEF and ywoBCD operons, which are not part of a previously characterized antibiotic-responsive regulon. Cluster analysis reveals that these two operons are selectively induced by a subset of cell wall antibiotics that inhibit lipid II function or recycling. Repression of both operons requires YtrA, which recognizes an inverted repeat in front of its own operon and in front of ywoB. These results suggest that YtrA is an additional regulator of cell envelope stress responses.
The Bacillus subtilis GntR Family Repressor YtrA Responds to Cell Wall Antibiotics▿§
Salzberg, Letal I.; Luo, Yun; Hachmann, Anna-Barbara; Mascher, Thorsten; Helmann, John D.
2011-01-01
The transglycosylation step of cell wall synthesis is a prime antibiotic target because it is essential and specific to bacteria. Two antibiotics, ramoplanin and moenomycin, target this step by binding to the substrate lipid II and the transglycosylase enzyme, respectively. Here, we compare the ramoplanin and moenomycin stimulons in the Gram-positive model organism Bacillus subtilis. Ramoplanin strongly induces the LiaRS two-component regulatory system, while moenomycin almost exclusively induces genes that are part of the regulon of the extracytoplasmic function (ECF) σ factor σM. Ramoplanin additionally induces the ytrABCDEF and ywoBCD operons, which are not part of a previously characterized antibiotic-responsive regulon. Cluster analysis reveals that these two operons are selectively induced by a subset of cell wall antibiotics that inhibit lipid II function or recycling. Repression of both operons requires YtrA, which recognizes an inverted repeat in front of its own operon and in front of ywoB. These results suggest that YtrA is an additional regulator of cell envelope stress responses. PMID:21856850
Probing the Intermediacy of Covalent RNA Enzyme Complexes in RNA Modification Enzymes
Chervin, Stephanie M.; Kittendorf, Jeffrey D.; Garcia, George A.
2009-01-01
Within the large and diverse group of RNA-modifying enzymes, a number of enzymes seem to form stable covalent linkages to their respective RNA substrates. A complete understanding of the chemical and kinetic mechanisms of these enzymes, some of which have identified pathological roles, is lacking. As part of our ongoing work studying the posttranscriptional modification of tRNA with queuine, we wish to understand fully the chemical and kinetic mechanisms involved in this key transglycosylation reaction. In our previous investigations, we have used a gel mobility-shift assay to characterize an apparent covalent enzyme-RNA intermediate believed to be operative in the catalytic pathway. However, the simple observation of a covalent complex is not sufficient to prove intermediacy. To be a true intermediate, the complex must be both chemically and kinetically competent. As a case study for the proof of intermediacy, we report the use of this gel-shift assay under mildly denaturing conditions to probe the kinetic competency of the covalent association between RNA and the tRNA modifying enzyme tRNA-guanine transglycosylase (TGT). PMID:17673081
Subsite mapping of enzymes. Application of the depolymerase computer model to two alpha-amylases.
Allen, J D; Thoma, J A
1976-01-01
In the preceding paper (Allen and Thoma, 1976) we developed a depolymerase computer model, which uses a minimization routine to establish a subsite map for a depolymerase. In the present paper we show how the model is applied to experimental data for two alpha-amylases. Michaelis parameters and bond-cleavage frequencies for substrates of chain lengths up to twelve glucosyl units have been reported for Bacillus amyloliquefaciens, and a subsite map has been proposed for this enzyme [Thoma et al. (1971) J. Biol. Chem. 246, 5621-5635]. By applying the computer model to the experimental data, we have arrived at a ten-subsite map. We find that a significant improvement in this map is achieved by allowing the hydrolytic rate coefficient to vary as a function of the number of occupied subsites comprising the enzyme-binding region. The bond-cleavage frequencies, the enzyme is found to have eight subsites. A partial subsite map is arrived at, but the entire binding region cannot be mapped because Michaelis parameters are complicated by transglycosylation reactions. The hydrolytic rate coefficients for this enzyme are not constant. PMID:999630
Biosynthesis of the fungal cell wall polysaccharide galactomannan requires intraluminal GDP-mannose.
Engel, Jakob; Schmalhorst, Philipp S; Routier, Françoise H
2012-12-28
Fungal cell walls frequently contain a polymer of mannose and galactose called galactomannan. In the pathogenic filamentous fungus Aspergillus fumigatus, this polysaccharide is made of a linear mannan backbone with side chains of galactofuran and is anchored to the plasma membrane via a glycosylphosphatidylinositol or is covalently linked to the cell wall. To date, the biosynthesis and significance of this polysaccharide are unknown. The present data demonstrate that deletion of the Golgi UDP-galactofuranose transporter GlfB or the GDP-mannose transporter GmtA leads to the absence of galactofuran or galactomannan, respectively. This indicates that the biosynthesis of galactomannan probably occurs in the lumen of the Golgi apparatus and thus contrasts with the biosynthesis of other fungal cell wall polysaccharides studied to date that takes place at the plasma membrane. Transglycosylation of galactomannan from the membrane to the cell wall is hypothesized because both the cell wall-bound and membrane-bound polysaccharide forms are affected in the generated mutants. Considering the severe growth defect of the A. fumigatus GmtA-deficient mutant, proving this paradigm might provide new targets for antifungal therapy.
Intact carbohydrate structures as part of the melanoidin skeleton.
Cämmerer, Bettina; Jalyschko, Walentina; Kroh, Lothar W
2002-03-27
Model melanoidins from monomeric, oligomeric, and polymeric carbohydrates, and amino acids formed under aqueous as well as water-free reaction conditions, were submitted to acidic catalyzed hydrolysis. Their degradation products were detected qualitatively and quantitatively by HPTLC and HPLC-DAD. A considerable amount of monomer carbohydrates from hydrolysis of model melanoidins formed under water-free reaction conditions was detected. It can be seen clearly that the amount of carbohydrates released increased with increasing degree of polymerization of the carbohydrates used as starting material. In comparison, the hydrolysis of melanoidins formed in aqueous condition resulted in only a small glucose release. It seems that in the Maillard reaction under water-free conditions, a significant amount of di- and oligomer carbohydrates were incorporated into the melanoidin skeleton as complete oligomer with intact glycosidic bond, forming side chains at the melanoidin skeleton. Additional side chains could be formed by transglycosylation reactions. With increasing water content, hydrothermolytic as well as retro-aldol reactions of the starting carbonyl components became significant, and therefore the possibility of forming side chains decreased. The results are consistent with the postulated melanoidin structure being built up mainly from sugar degradation products, probably branched via amino compounds.
Wong, Fai-Chu; Chai, Tsun-Thai; Xiao, Jianbo
2018-05-22
In our diets, many of the consumed foods are subjected to various forms of heating and thermal processing. Besides enhancing the taste, texture, and aroma of the foods, heating helps to sterilize and facilitate food storage. On the other hand, heating and thermal processing are frequently reported during the preparation of various traditional herbal medicines. In this review, we intend to highlight works by various research groups which reported on changes in phytochemicals and bioactivities, following thermal processing of selected plant-derived foods and herbal medicines. Relevant cases from plant-derived foods (garlic, coffee, cocoa, barley) and traditional herbal medicines (Panax ginseng, Polygonum multiforum, Aconitum carmichaelii Debeaux, Angelica sinensis Radix) will be presented in this review. Additionally, related works using pure phytochemical compounds will also be highlighted. In some of these cases, the amazing formation of new compounds were being reported. Maillard reaction could be concluded as the predominant pathway leading to the formation of new conjugates, along with other possibilities being suggested (degradation, transglycosylation, deglycosylation and dehydration). With collective efforts from all researchers, it is hoped that more details will be revealed and lead to the possible discovery of new, heat-mediated phytochemical conjugates.
Crost, Emmanuelle H; Tailford, Louise E; Monestier, Marie; Swarbreck, David; Henrissat, Bernard; Crossman, Lisa C; Juge, Nathalie
2016-07-03
We previously identified and characterized an intramolecular trans-sialidase (IT-sialidase) in the gut symbiont Ruminococcus gnavus ATCC 29149, which is associated to the ability of the strain to grow on mucins. In this work we have obtained and analyzed the draft genome sequence of another R. gnavus mucin-degrader, ATCC 35913, isolated from a healthy individual. Transcriptomics analyses of both ATCC 29149 and ATCC 35913 strains confirmed that the strategy utilized by R. gnavus for mucin-degradation is focused on the utilization of terminal mucin glycans. R. gnavus ATCC 35913 also encodes a predicted IT-sialidase and harbors a Nan cluster dedicated to sialic acid utilization. We showed that the Nan cluster was upregulated when the strains were grown in presence of mucin. In addition we demonstrated that both R. gnavus strains were able to grow on 2,7-anyhydro-Neu5Ac, the IT-sialidase transglycosylation product, as a sole carbon source. Taken together these data further support the hypothesis that IT-sialidase expressing gut microbes, provide commensal bacteria such as R. gnavus with a nutritional competitive advantage, by accessing and transforming a source of nutrient to their own benefit.
Nam, Seung-Hee; Park, Jeongjin; Jun, Woojin; Kim, Doman; Ko, Jin-A; Abd El-Aty, A M; Choi, Jin Young; Kim, Do-Ik; Yang, Kwang-Yeol
2017-12-22
Gallic acid glycoside was enzymatically synthesized by using dextransucrase and sucrose from gallic acid. After purification by butanol partitioning and preparative HPLC, gallic acid glucoside was detected at m/z 355 (C 13 , H 16 , O 10 , Na) + by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The yield of gallic acid glucoside was found to be 35.7% (114 mM) by response surface methodology using a reaction mixture of 319 mM gallic acid, 355 mM sucrose, and 930 mU/mL dextransucrase. The gallic acid glucoside obtained showed 31% higher anti-lipid peroxidation and stronger inhibition (Ki = 1.23 mM) against tyrosinase than that shown by gallic acid (Ki = 1.98 mM). In UVB-irradiated human fibroblast cells, gallic acid glucoside lowered matrix metalloproteinase-1 levels and increased the collagen content, which was indicative of a stronger anti-aging effect than that of gallic acid or arbutin. These results indicated that gallic acid glucoside is likely a superior cosmetic ingredient with skin-whitening and anti-aging functions.
2013-01-01
Background The study of coffee polysaccharides-degrading enzymes from the coffee berry borer Hypothenemus hampei, has become an important alternative in the identification for enzymatic inhibitors that can be used as an alternative control of this dangerous insect. We report the cloning, expression and biochemical characterization of a mannanase gene that was identified in the midgut of the coffee berry borer and is responsible for the degradation of the most abundant polysaccharide in the coffee bean. Methods The amino acid sequence of HhMan was analyzed by multiple sequence alignment comparisons with BLAST (Basic Local Alignment Search Tool) and CLUSTALW. A Pichia pastoris expression system was used to express the recombinant form of the enzyme. The mannanase activity was quantified by the 3,5-dinitrosalicylic (DNS) and the hydrolitic properties were detected by TLC. Results An endo-1,4-β-mannanase from the digestive tract of the insect Hypothenemus hampei was cloned and expressed as a recombinant protein in the Pichia pastoris system. This enzyme is 56% identical to the sequence of an endo-β-mannanase from Bacillus circulans that belongs to the glycosyl hydrolase 5 (GH5) family. The purified recombinant protein (rHhMan) exhibited a single band (35.5 kDa) by SDS-PAGE, and its activity was confirmed by zymography. rHhMan displays optimal activity levels at pH 5.5 and 30°C and can hydrolyze galactomannans of varying mannose:galactose ratios, suggesting that the enzymatic activity is independent of the presence of side chains such as galactose residues. The enzyme cannot hydrolyze manno-oligosaccharides such as mannobiose and mannotriose; however, it can degrade mannotetraose, likely through a transglycosylation reaction. The Km and kcat values of this enzyme on guar gum were 2.074 mg ml-1 and 50.87 s-1, respectively, which is similar to other mannanases. Conclusion This work is the first study of an endo-1,4-β-mannanase from an insect using this expression system. Due to this enzyme’s importance in the digestive processes of the coffee berry borer, this study may enable the design of inhibitors against endo-1,4-β-mannanase to decrease the economic losses stemming from this insect. PMID:23965285
Moreira, Ana S P; Coimbra, Manuel A; Nunes, Fernando M; Simões, Joana; Domingues, M Rosário M
2011-09-28
The roasting process induces structural changes in coffee galactomannans. To know more about the reaction pathways that occur during the roasting of coffee, mannosyl and galactomannosyl oligosaccharides, having a degree of polymerization (DP) between 3 and 4, were used as models for galactomannans. These compounds were dry-heated under air atmosphere from room temperature to 200 °C, being maintained at 200 °C for different periods of time. The roasted materials were analyzed by mass spectrometry (ESI-MS, MALDI-MS, and ESI-MSn) and methylation analysis. In the MS spectra were identified several [M+Na]+ ions belonging to a series from a single hexose to 10 hexose residues ([Hex1-10+Na]+). The ions corresponding to their respective mono- and tridehydrated derivatives ([Hex2-10-H2O+Na]+ and [Hex2-10-3H2O+Na]+, respectively) were also identified. ESI-MSn as well as deuterium-labeling and alditol derivatization experiments showed that the tridehydrations occur at the reducing end of the oligosaccharides. The identification of (1→2)- and (1→6)-linked mannose residues and (1→4)-linked glucose residues by methylation analysis allowed the conclusion that transglycosylation and isomerization reactions occur during dry thermal processing.
Sabater, Carlos; Olano, Agustín; Prodanov, Marin; Montilla, Antonia; Corzo, Nieves
2017-12-01
One of the most promising uses of whey permeate (WP) is the synthesis of prebiotic oligosaccharides. Herein, commercial WP was submitted to chemical isomerization catalysed by sodium borate at an alkaline pH and subsequent purification using anion-exchange resins to remove boron. Subsequently, purified mixtures were used to synthesize prebiotic oligosaccharides using β-galactosidase from Bacillus circulans. Isomerization of concentrated WP (200 g L -1 lactose) gave rise to levels of lactulose up to 155.5 g L -1 after 30 min of reaction (molar ratio of boron/lactose, 1/1; pH 12; 70 °C). Boron was removed from the isomerized WP (IWP) using the combination of a strong acid (IR-120, H + ) and a weak base (IRA-743) anion-exchange resins, reducing its level to <1 ppm, without loss of lactulose. During the transglycosylation reaction of purified IWP (lactose/lactulose ratio, 1/2.4) maximum content of prebiotic compounds was achieved, i.e. 690 g kg -1 WP after 3 h of reaction. This study shows that combined chemical-enzymatic reactions together with the purification of IWP results in an efficient synthesis of prebiotic oligosaccharides. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Site-specific creation of uridine from cytidine in apolipoprotein B mRNA editing.
Hodges, P E; Navaratnam, N; Greeve, J C; Scott, J
1991-01-01
Human apolipoprotein (apo) B mRNA is edited in a tissue specific reaction, to convert glutamine codon 2153 (CAA) to a stop translation codon. The RNA editing product templates and hybridises as uridine, but the chemical nature of this reaction and the physical identity of the product are unknown. After editing in vitro of [32P] labelled RNA, we are able to demonstrate the production of uridine from cytidine; [alpha 32P] cytidine triphosphate incorporated into RNA gave rise to [32P] uridine monophosphate after editing in vitro, hydrolysis with nuclease P1 and thin layer chromatography using two separation systems. By cleaving the RNA into ribonuclease T1 fragments, we show that uridine is produced only at the authentic editing site and is produced in quantities that parallel an independent primer extension assay for editing. We conclude that apo B mRNA editing specifically creates a uridine from a cytidine. These observations are inconsistent with the incorporation of a uridine nucleotide by any polymerase, which would replace the alpha-phosphate and so rule out a model of endonucleolytic excision and repair as the mechanism for the production of uridine. Although transamination and transglycosylation remain to be formally excluded as reaction mechanisms our results argue strongly in favour of the apo B mRNA editing enzyme as a site-specific cytidine deaminase. Images PMID:2030940
Cutillas-Iturralde, A.; Lorences, E. P.
1997-01-01
The growth-promoting effect of xyloglucan-derived oligosaccharides was investigated using a bioassay with entire pea (Pisum sativum L., var Alaska) shoots. After a 24-h incubation period at 25[deg]C, xyloglucan oligosaccharide (XGO) solutions with concentrations of 10-6 M notably increased the growth rate of pea shoots, whereas the same oligosaccharides at 10-7 M were less effective. To investigate the possible correlation between growth rate changes in the XGO-treated shoots and changes in the wall mechanical properties of their growing regions (third internodes), we used a short-term creep assay. The promotion of elongation by XGOs was reflected in an enhancement of the viscoelasticity of the growing regions of the shoots. To show whether this effect on wall viscoelastic properties was the cause or a consequence of their growth promotion, we tested the effect of XGOs on the long-term extension of isolated cell walls. We characterized an acid-induced extension in isolated cell walls from pea shoots that was not inhibited by preincubation in neutral buffers. Exogenously added XGOs did not alter the pattern of pea segment extension at any pH tested, indicating that XGOs have no direct effect on cell wall viscoelasticity. Finally, preincubation of pea segments in neutral buffers with XGOs enhanced their capacity to extend under acidic conditions. This finding suggests that XGOs at a neutral pH can act via transglycosylation, weakening the wall matrix and making the wall more responsive to other mechanisms of acid-induced extension as an expansin-mediated extension. PMID:12223593
Enzyme and microbial technology for synthesis of bioactive oligosaccharides: an update.
Chen, Rachel
2018-04-01
Oligosaccharides, in either free or bound forms, play crucial roles in a wide range of biological processes. Increasing appreciation of their roles in cellular communication, interaction, pathogenesis, and prebiotic functions has stimulated tremendous interests in their synthesis. Pure and structurally defined oligosaccharides are essential for fundamental studies. On the other hand, for those with near term medical and nutraceutical applications, their large-scale synthesis is necessary. Unfortunately, oligosaccharides are notoriously difficult in their synthesis, and their enormous diverse structures leave a vast gap between what have been synthesized in laboratory and those present in various biological systems. While enzymes and microbes are nature's catalysts for oligosaccharides, their effective use is not without challenges. Using examples of galactose-containing oligosaccharides, this review analyzes the pros and cons of these two forms of biocatalysts and provides an updated view on the status of biocatalysis in this important field. Over the past few years, a large number of novel galactosidases were discovered and/or engineered for improved synthesis via transglycosylation. The use of salvage pathway for regeneration of uridine diphosphate (UDP)-galactose has made the use of Leloir glycosyltransferases simpler and more efficient. The recent success of large-scale synthesis of 2' fucosyllactose heralded the power of whole-cell biocatalysis as a scalable technology. While it still lags behind enzyme catalysis in terms of the number of oligosaccharides synthesized, an acceleration in the use of this form of biocatalyst is expected as rapid advances in synthetic biology have made the engineering of whole cell biocatalysts less arduous and less time consuming.
Bidart, Gonzalo N; Rodríguez-Díaz, Jesús; Palomino-Schätzlein, Martina; Monedero, Vicente; Yebra, María J
2017-01-01
Lacto-N-biose (LNB) and galacto-N-biose (GNB) are major building blocks of free oligosaccharides and glycan moieties of glyco-complexes present in human milk and gastrointestinal mucosa. We have previously characterized the phospho-β-galactosidase GnbG from Lactobacillus casei BL23 that is involved in the metabolism of LNB and GNB. GnbG has been used here in transglycosylation reactions, and it showed the production of LNB and GNB with N-acetylglucosamine and N-acetylgalactosamine as acceptors, respectively. The reaction kinetics demonstrated that GnbG can convert 69 ± 4 and 71 ± 1 % of o-nitrophenyl-β-D-galactopyranoside into LNB and GNB, respectively. Those reactions were performed in a semi-preparative scale, and the synthesized disaccharides were purified. The maximum yield obtained for LNB was 10.7 ± 0.2 g/l and for GNB was 10.8 ± 0.3 g/l. NMR spectroscopy confirmed the molecular structures of both carbohydrates and the absence of reaction byproducts, which also supports that GnbG is specific for β1,3-glycosidic linkages. The purified sugars were subsequently tested for their potential prebiotic properties using Lactobacillus species. The results showed that LNB and GNB were fermented by the tested strains of L. casei, Lactobacillus rhamnosus (except L. rhamnosus strain ATCC 53103), Lactobacillus zeae, Lactobacillus gasseri, and Lactobacillus johnsonii. DNA hybridization experiments suggested that the metabolism of those disaccharides in 9 out of 10 L. casei strains, all L. rhamnosus strains and all L. zeae strains tested relies upon a phospho-β-galactosidase homologous to GnbG. The results presented here support the putative role of human milk oligosaccharides for selective enrichment of beneficial intestinal microbiota in breast-fed infants.
Reaction mechanism of chitosanase from Streptomyces sp. N174.
Fukamizo, T; Honda, Y; Goto, S; Boucher, I; Brzezinski, R
1995-01-01
Chitosanase was produced by the strain of Streptomyces lividans TK24 bearing the csn gene from Streptomyces sp. N174, and purified by S-Sepharose and Bio-Gel A column chromatography. Partially (25-35%) N-acetylated chitosan was digested by the purified chitosanase, and structures of the products were analysed by NMR spectroscopy. The chitosanase produced heterooligosaccharides consisting of D-GlcN and GlcNAc in addition to glucosamine oligosaccharides [(GlcN)n, n = 1, 2 and 3]. The reducing- and non-reducing-end residues of the heterooligosaccharide products were GlcNAc and GlcN respectively, indicating that the chitosanase can split the GlcNAc-GlcN linkage in addition to that of GlcN-GlcN. Time-dependent 1H-NMR spectra showing hydrolysis of (GlcN)6 by the chitosanase were obtained in order to determine the anomeric form of the reaction products. The chitosanase was found to produce only the alpha-form; therefore it is an inverting enzyme. Separation and quantification of (GlcN)n was achieved by HPLC, and the time course of the reaction catalysed by the chitosanase was studied using (GlcN)n (n = 4, 5 and 6) as the substrate. The chitosanase hydrolysed (GlcN)6 in an endo-splitting manner producing (GlcN)2, (GlcN)3 and (GlcN)4, and did not catalyse transglycosylation. Product distribution was (GlcN)3 >> (GlcN)2 > (GlcN)4. Cleavage to (GlcN)3 + (GlcN)3 predominated over that to (GlcN)2 + (GlcN)4. Time courses showed a decrease in rate of substrate degradation from (GlcN)6 to (GlcN)5 to (GlcN)4. It is most likely that the substrate-binding cleft of the chitosanase can accommodate at least six GlcN residues, and that the cleavage point is located at the midpoint of the binding cleft. PMID:7487871
Hrmova, Maria; Burton, Rachel A.; Biely, Peter; Lahnstein, Jelle; Fincher, Geoffrey B.
2006-01-01
A family GH5 (family 5 glycoside hydrolase) (1,4)-β-D-mannan endohydrolase or β-D-mannanase (EC 3.2.1.78), designated HvMAN1, has been purified 300-fold from extracts of 10-day-old barley (Hordeum vulgare L.) seedlings using ammonium sulfate fractional precipitation, followed by ion exchange, hydrophobic interaction and size-exclusion chromatography. The purified HvMAN1 is a relatively unstable enzyme with an apparent molecular mass of 43 kDa, a pI of 7.8 and a pH optimum of 4.75. The HvMAN1 releases Man (mannose or D-mannopyranose)-containing oligosaccharides of degree of polymerization 2–6 from mannans, galactomannans and glucomannans. With locust-bean galactomannan and mannopentaitol as substrates, the enzyme has Km constants of 0.16 mg·ml−1 and 5.3 mM and kcat constants of 12.9 and 3.9 s−1 respectively. Product analyses indicate that transglycosylation reactions occur during hydrolysis of (1,4)-β-D-manno-oligosaccharides. The complete sequence of 374 amino acid residues of the mature enzyme has been deduced from the nucleotide sequence of a near full-length cDNA, and has allowed a three-dimensional model of the HvMAN1 to be constructed. The barley HvMAN1 gene is a member of a small (1,4)-β-D-mannan endohydrolase family of at least six genes, and is transcribed at low levels in a number of organs, including the developing endosperm, but also in the basal region of young roots and in leaf tips. A second barley enzyme that participates in mannan depolymerization through its ability to hydrolyse (1,4)-β-D-manno-oligosaccharides to Man is a family GH1 β-D-mannosidase, now designated HvβMANNOS1, but previously identified as a β-D-glucosidase [Hrmova, MacGregor, Biely, Stewart and Fincher (1998) J. Biol. Chem. 273, 11134–11143], which hydrolyses 4NP (4-nitrophenyl) β-D-mannoside three times faster than 4NP β-D-glucoside, and has an action pattern typical of a (1,4)-β-D-mannan exohydrolase. PMID:16771710
Wong, Suzy L; Leatherdale, Scott T
2009-01-01
Sedentary behavior and physical activity are not mutually exclusive behaviors. The relative risk of overweight for adolescents who are highly sedentary and highly physically active is unclear. A better understanding of the relationship between sedentary behaviors, physical activity, and body mass index (BMI) would provide insight for developing interventions to prevent or reduce overweight. Using the physical activity module of the School Health Action, Planning and Evaluation System (SHAPES), we collected data from 25,060 students in grades 9 through 12 from 76 secondary schools in Ontario, Canada. Sex-specific logistic regression analyses were performed to examine how BMI, weight perceptions, social influences, team sports participation, and smoking behavior were associated with being 1) high active-high sedentary, 2) low active-low sedentary, and 3) low active-high sedentary. Low active-high sedentary boys were more likely to be overweight than high active-low sedentary boys (adjusted odds ratio [AOR], 1.60; 95% confidence interval [CI], 1.01-2.58). When compared with high active-low sedentary girls, girls who were low active-high sedentary (OR, 2.24; 95% CI, 1.23-4.09) or high active-high sedentary (OR, 1.91; 95% CI, 1.01-3.61) were more likely to be overweight. Sedentary behavior may moderate the relationship between physical activity and overweight. Developing a better understanding of sedentary behavior in relation to physical activity and overweight is critical for preventing and reducing overweight among youth.
ERIC Educational Resources Information Center
de Vries, Jannes; de Graaf, Paul M.
2008-01-01
In this article we study the bias caused by the conventional retrospective measurement of parental high cultural activities in the effects of parental high cultural activities and educational attainment on son's or daughter's high cultural activities. Multi-informant data show that there is both random measurement error and correlated error in the…
Relative ability of fat and sugar tastes to activate reward, gustatory, and somatosensory regions.
Stice, Eric; Burger, Kyle S; Yokum, Sonja
2013-12-01
Although the intake of high-fat and high-sugar food activates mesolimbic reward, gustatory, and oral somatosensory brain regions, contributing to overeating, few studies have examined the relative role of fat and sugar in the activation of these brain regions, which would inform policy, prevention, and treatment interventions designed to reduce obesity. We evaluated the effect of a high-fat or high-sugar equicaloric chocolate milkshake and increasing fat or sugar milkshake content on the activation of these regions. Functional magnetic resonance imaging was used to assess the neural response to the intake of high-fat/high-sugar, high-fat/low-sugar, low-fat/high-sugar, and low-fat/low-sugar chocolate milkshakes and a tasteless solution in 106 lean adolescents (mean ± SD age = 15.00 ± 0.88 y). Analyses contrasted the activation to the various milkshakes. High-fat compared with high-sugar equicaloric milkshakes caused greater activation in the bilateral caudate, postcentral gyrus, hippocampus, and inferior frontal gyrus. High-sugar compared with high-fat equicaloric milkshakes caused greater activation in the bilateral insula extending into the putamen, the Rolandic operculum, and thalamus, which produced large activation regions. Increasing sugar in low-fat milkshakes caused greater activation in the bilateral insula and Rolandic operculum; increasing fat content did not elicit greater activation in any region. Fat caused greater activation of the caudate and oral somatosensory regions than did sugar, sugar caused greater activation in the putamen and gustatory regions than did fat, increasing sugar caused greater activity in gustatory regions, and increasing fat did not affect the activation. Results imply that sugar more effectively recruits reward and gustatory regions, suggesting that policy, prevention, and treatment interventions should prioritize reductions in sugar intake. This trial was registered at clinicaltrials.gov as DK092468.
Code of Federal Regulations, 2014 CFR
2014-10-01
... aircraft conducting high-frequency or non-hull-mounted mid-frequency active sonar activities associated... or aircraft conducting high-frequency active sonar activities associated with anti-submarine warfare...). (2) High-frequency and non-hull mounted mid-frequency active sonar (except helicopter dipping). (3...
Physical activity behavior and related characteristics of highly active eighth-grade girls.
Taverno Ross, Sharon E; Dowda, Marsha; Beets, Michael W; Pate, Russell R
2013-06-01
Although girls are generally less physically active than boys, some girls regularly engage in high levels of physical activity (PA); however, very little is known about these girls and how they differ from those who are less physically active. This study examined the PA behavior and related characteristics of highly active adolescent girls and compared them with those who are less active. Data from 1,866 eighth-grade girls from six field centers across the United States participating in the Trial of Activity for Adolescent Girls (TAAG) were included in the present analysis. Mixed-model analysis of variance examined differences in sociodemographic, anthropometric, psychosocial, and physical activity (accelerometry and self-report) variables between high- and low-active girls; effect sizes were calculated for the differences. High-active girls were taller, had lower body mass indices and body fat, and were less sedentary. High-active girls scored higher on self-efficacy, enjoyment of PA, self-management strategies, outcome-expectancy value, and support from family and friends than low-active girls. Low-active girls participated in more leisure time and educational sedentary activities than high-active girls. High-active girls participated in more PA classes/lessons outside of school, team sports, and individual sports. They were also more likely to participate in sports in an organized setting in the community or at school than low-active girls. Health promotion efforts should focus on decreasing the amount of time girls spend in sedentary activities and replacing that time with organized PA opportunities; such efforts should seek to minimize perceived barriers and increase self-efficacy and support for PA. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Sparks, Robert E. C.
A growing number of schools and institutions in North America have begun offering training in high risk activities such as high element rope courses, rock climbing, white water kayaking and canoeing, and scuba diving in conjunction with their regular physical education activity programs. High risk activities are those activities which occur in or…
Hou, Chia-Hung; Liu, Nei-Ling; Hsi, Hsing-Cheng
2015-12-01
Highly porous activated carbons were resource-recovered from Leucaena leucocephala (Lam.) de Wit. wood through combined chemical and physical activation (i.e., KOH etching followed by CO2 activation). This invasive species, which has severely damaged the ecological economics of Taiwan, was used as the precursor for producing high-quality carbonaceous electrodes for capacitive deionization (CDI). Carbonization and activation conditions strongly influenced the structure of chars and activated carbons. The total surface area and pore volume of activated carbons increased with increasing KOH/char ratio and activation time. Overgasification induced a substantial amount of mesopores in the activated carbons. In addition, the electrochemical properties and CDI electrosorptive performance of the activated carbons were evaluated; cyclic voltammetry and galvanostatic charge/discharge measurements revealed a typical capacitive behavior and electrical double layer formation, confirming ion electrosorption in the porous structure. The activated-carbon electrode, which possessed high surface area and both mesopores and micropores, exhibited improved capacitor characteristics and high electrosorptive performance. Highly porous activated carbons derived from waste L. leucocephala were demonstrated to be suitable CDI electrode materials. Copyright © 2015 Elsevier Ltd. All rights reserved.
Differential skeletal muscle proteome of high- and low-active mice
Dangott, Lawrence J.; Schmitt, Emily E.; Vellers, Heather L.; Lightfoot, J. Timothy
2014-01-01
Physical inactivity contributes to cardiovascular disease, type II diabetes, obesity, and some types of cancer. While the literature is clear that there is genetic regulation of physical activity with existing gene knockout data suggesting that skeletal muscle mechanisms contribute to the regulation of activity, actual differences in end-protein expression between high- and low-active mice have not been investigated. This study used two-dimensional differential gel electrophoresis coupled with mass spectrometry to evaluate the proteomic differences between high-active (C57L/J) and low-active (C3H/HeJ) mice in the soleus and extensor digitorum longus (EDL). Furthermore, vivo-morpholinos were used to transiently knockdown candidate proteins to confirm their involvement in physical activity regulation. Proteins with higher expression patterns generally fell into the calcium-regulating and Krebs (TCA) cycle pathways in the high-active mice (e.g., annexin A6, P = 0.0031; calsequestrin 1; P = 0.000025), while the overexpressed proteins in the low-active mice generally fell into cytoskeletal structure- and electron transport chain-related pathways (e.g., ATPase, P = 0.031; NADH dehydrogenase, P = 0.027). Transient knockdown of annexin A6 and calsequestrin 1 protein of high-active mice with vivo-morpholinos resulted in decreased physical activity levels (P = 0.001). These data suggest that high- and low-active mice have unique protein expression patterns and that each pattern contributes to the peripheral capability to be either high- or low-active, suggesting that different specific mechanisms regulate activity leading to the high- or low-activity status of the animal. PMID:24505100
Sergutina, A V; Rakhmanova, V I
2016-06-01
Monoamine oxidase activity was quantitatively assessed by cytochemical method in brain structures (layers III and V of the sensorimotor cortex, caudate nucleus, nucleus accumbens, hippocampal CA3 field) of rats of August line and Wistar population with high and low locomotor activity in the open fi eld test. Monoamine oxidase activity (substrate tryptamine) predominated in the nucleus accumbens of Wistar rats with high motor activity in comparison with rats with low locomotor activity. In August rats, enzyme activity (substrates tryptamine and serotonin) predominated in the hippocampus of animals with high motor activity. Comparison of August rats with low locomotor activity and Wistar rats with high motor activity (i.e. animals demonstrating maximum differences in motor function) revealed significantly higher activity of the enzyme (substrates tryptamine and serotonin) in the hippocampus of Wistar rats. The study demonstrates clear-cut morphochemical specificity of monoaminergic metabolism based on the differences in the cytochemical parameter "monoamine oxidase activity", in the studied brain structures, responsible for the formation and realization of goal-directed behavior in Wistar and August rats.
The secrets of highly active older adults.
Franke, Thea; Tong, Catherine; Ashe, Maureen C; McKay, Heather; Sims-Gould, Joanie
2013-12-01
Although physical activity is a recognized component in the management of many chronic diseases associated with aging, activity levels tend to progressively decline with increasing age (Manini & Pahor, 2009; Schutzer & Graves, 2004). In this article we examine the key factors that facilitate physical activity in highly active community-dwelling older adults. Using a strengths based approach, we examined the factors that facilitated physical activity in our sample of highly active older adults. Twenty-seven older adults participated in face-to face interviews. We extracted a sub-sample of 10 highly active older adults to be included in the analyses. Based on a framework analysis of our transcripts we identified three factors that facilitate physical activity in our sample, these include: 1) resourcefulness: engagement in self-help strategies such as self-efficacy, self-control and adaptability; 2) social connections: the presence of relationships (friend, neighborhood, institutions) and social activities that support or facilitate high levels of physical activity; and 3) the role of the built and natural environments: features of places and spaces that support and facilitate high levels of physical activity. Findings provide insight into, and factors that facilitate older adults' physical activity. We discuss implications for programs (e.g., accessible community centers, with appropriate programming throughout the lifecourse) and policies geared towards the promotion of physical activity (e.g., the development of spaces that facilitate both physical and social activities). © 2013.
Baquet, Georges; Ridgers, Nicola D; Blaes, Aurélie; Aucouturier, Julien; Van Praagh, Emmanuel; Berthoin, Serge
2014-02-21
The school environment influences children's opportunities for physical activity participation. The aim of the present study was to assess objectively measured school recess physical activity in children from high and low socioeconomic backgrounds. Four hundred and seven children (6-11 years old) from 4 primary schools located in high socioeconomic status (high-SES) and low socioeconomic status (low-SES) areas participated in the study. Children's physical activity was measured using accelerometry during morning and afternoon recess during a 4-day school week. The percentage of time spent in light, moderate, vigorous, very high and in moderate- to very high-intensity physical activity were calculated using age-dependent cut-points. Sedentary time was defined as 100 counts per minute. Boys were significantly (p < 0.001) more active than girls. No difference in sedentary time between socioeconomic backgrounds was observed. The low-SES group spent significantly more time in light (p < 0.001) and very high (p < 0.05) intensity physical activity compared to the high-SES group. High-SES boys and girls spent significantly more time in moderate (p < 0.001 and p < 0.05, respectively) and vigorous (p < 0.001) physical activity than low-SES boys. Differences were observed in recess physical activity levels according to socioeconomic background and sex. These results indicate that recess interventions should target children in low-SES schools.
Høi-Hansen, Thomas; Pedersen-Bjergaard, Ulrik; Andersen, Rikke Due; Kristensen, Peter Lommer; Thomsen, Carsten; Kjaer, Troels; Høgenhaven, Hans; Smed, Annelise; Holst, Jens Juul; Dela, Flemming; Boomsma, Frans; Thorsteinsson, Birger
2009-12-01
High basal renin-angiotensin system (RAS) activity is associated with increased risk of severe hypoglycaemia in type 1 diabetes. We tested whether this might be explained by more pronounced cognitive dysfunction during hypoglycaemia in patients with high RAS activity than in patients with low RAS activity. Nine patients with type 1 diabetes and high and nine with low RAS activity were subjected to hypoglycaemia and euglycaemia in a cross-over study using an intravenous insulin infusion protocol. Cognitive function, electroencephalography, auditory evoked potentials and hypoglycaemic symptoms were recorded. At a hypoglycaemic nadir of 2.2 (SD 0.3) mmol/L the high RAS group displayed significant deterioration in cognitive performance during hypoglycaemia in the three most complex reaction time tasks. In the low RAS group, hypoglycaemia led to cognitive dysfunction in only one reaction time task. The high RAS group reported lower symptom scores during hypoglycaemia than the low RAS group, suggesting poorer hypoglycaemia awareness. High RAS activity is associated with increased cognitive dysfunction and blunted symptoms during mild hypoglycaemia compared to low RAS activity. This may explain why high RAS activity is a risk factor for severe hypoglycaemia in type 1 diabetes.
Tekere, M; Zvauya, R; Read, J S
2001-01-01
Lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase activities in selected sub-tropical white rot fungal species from Zimbabwe were determined. The enzyme activities were assayed at varying concentrations of C, N and Mn2+. Manganese peroxidase and laccase activities were the only expressed activities in the fungi under the culture conditions tested. Trametes species, T. cingulata, T. elegans and T. pocas produced the highest manganese peroxidase activities in a medium containing high carbon and low nitrogen conditions. High nitrogen conditions favoured high manganese peroxidase activity in DSPM95, L. velutinus and Irpex spp. High manganese peroxidase activity was notable for T. versicolor when both carbon and nitrogen in the medium were present at high levels. Laccase production by the isolates was highest under conditions of high nitrogen and those conditions with both nitrogen and carbon at high concentration. Mn2+ concentrations between 11-25 ppm gave the highest manganese peroxidase activity compared to a concentration of 40 ppm or when there was no Mn2+ added. Laccase activity was less influenced by Mn2+ levels. While some laccase activity was produced in the absence of Mn2+, the enzyme levels were higher when Mn2+ was added to the culture medium.
Wiebking, Christine; Northoff, Georg
2015-01-01
Objective: Alexithymia relates to difficulties recognizing and describing emotions. It has been linked to subjectively increased interoceptive awareness (IA) and to psychiatric illnesses such as major depressive disorder (MDD) and somatization. MDD in turn is characterized by aberrant emotion processing and IA on the subjective as well as on the neural level. However, a link between neural activity in response to IA and alexithymic traits in health and depression remains unclear. Methods: A well-established fMRI task was used to investigate neural activity during IA (heartbeat counting) and exteroceptive awareness (tone counting) in non-psychiatric controls (NC) and MDD. Firstly, comparing MDD and NC, a linear relationship between IA-related activity and scores of the Toronto Alexithymia Scale (TAS) was investigated through whole-brain regression. Secondly, NC were divided by median-split of TAS scores into groups showing low (NC-low) or high (NC-high) alexithymia. MDD and NC-high showed equally high TAS scores. Subsequently, IA-related neural activity was compared on a whole-brain level between the three independent samples (MDD, NC-low, NC-high). Results: Whole-brain regressions between MDD and NC revealed neural differences during IA as a function of TAS-DD (subscale difficulty describing feelings) in the supragenual anterior cingulate cortex (sACC; BA 24/32), which were due to negative associations between TAS-DD and IA-related activity in NC. Contrasting NC subgroups after median-split on a whole-brain level, high TAS scores were associated with decreased neural activity during IA in the sACC and increased insula activity. Though having equally high alexithymia scores, NC-high showed increased insula activity during IA compared to MDD, whilst both groups showed decreased activity in the sACC. Conclusions: Within the context of decreased sACC activity during IA in alexithymia (NC-high and MDD), increased insula activity might mirror a compensatory mechanism in NC-high, which is disrupted in MDD. PMID:26074827
Aloe vera Derived Activated High-Surface-Area Carbon for Flexible and High-Energy Supercapacitors.
Karnan, M; Subramani, K; Sudhan, N; Ilayaraja, N; Sathish, M
2016-12-28
Materials which possess high specific capacitance in device configuration with low cost are essential for viable application in supercapacitors. Herein, a flexible high-energy supercapacitor device was fabricated using porous activated high-surface-area carbon derived from aloe leaf (Aloe vera) as a precursor. The A. vera derived activated carbon showed mesoporous nature with high specific surface area of ∼1890 m 2 /g. A high specific capacitance of 410 and 306 F/g was achieved in three-electrode and symmetric two-electrode system configurations in aqueous electrolyte, respectively. The fabricated all-solid-state device showed a high specific capacitance of 244 F/g with an energy density of 8.6 Wh/kg. In an ionic liquid electrolyte, the fabricated device showed a high specific capacitance of 126 F/g and a wide potential window up to 3 V, which results in a high energy density of 40 Wh/kg. Furthermore, it was observed that the activation temperature has significant role in the electrochemical performance, as the activated sample at 700 °C showed best activity than the samples activated at 600 and 800 °C. The electron microscopic images (FE-SEM and HR-TEM) confirmed the formation of pores by the chemical activation. A fabricated supercapacitor device in ionic liquid with 3 V could power up a red LED for 30 min upon charging for 20s. Also, it is shown that the operation voltage and capacitance of flexible all-solid-state symmetric supercapacitors fabricated using aloe-derived activated carbon could be easily tuned by series and parallel combinations. The performance of fabricated supercapacitor devices using A. vera derived activated carbon in all-solid-state and ionic liquid indicates their viable applications in flexible devices and energy storage.
50 CFR 216.170 - Specified activity and specified geographical region.
Code of Federal Regulations, 2013 CFR
2013-10-01
... incidental to the following activities: (1) The use of the following mid-frequency active sonar (MFAS) and high frequency active sonar (HFAS) sources, or similar sources, for Navy training activities (estimated amounts below): (1) The use of the following mid-frequency active sonar (MFAS) and high frequency active...
50 CFR 216.170 - Specified activity and specified geographical region.
Code of Federal Regulations, 2012 CFR
2012-10-01
... incidental to the following activities: (1) The use of the following mid-frequency active sonar (MFAS) and high frequency active sonar (HFAS) sources, or similar sources, for Navy training activities (estimated amounts below): (1) The use of the following mid-frequency active sonar (MFAS) and high frequency active...
A comparison of bat activity at low and high elevations in the Black Hills of western Washington
Erickson, J.; Adams, Michael J.
2003-01-01
We examined the differences in activity patterns and community structure of bats between low (<150 m) and high ( ! 575 m) elevation sites in two habitats of the Capitol State Forest, Washington. Total bat activity averaged four times higher at low elevation sites than at high elevation sites. Feeding activity was almost 20 times higher at low elevation sites. However, the non-myotis group had similar activity levels at high and low elevation, whereas myotis group activity decreased at higher elevations. Different levels of activity between elevations could be the result of differences in insect availability, climatic conditions, and morphology of the bat species.
Robinson, M L; Winters-Stone, K; Gabel, K; Dolny, D
2007-08-01
One hundred and fourteen girls were measured for calcaneus QUS (stiffness index score), calcium intake, weight, and total hours spent in physical activity (moderate to high-impact activities and low to no-impact activities). Multiple regression analysis indicated that hours spent in moderate to high-impact activities, current calcium intake, and weight significantly predicted SI. To determine the influence of modifiable lifestyle factors on adolescent girls' bone health measured by calcaneus quantitative ultrasound (QUS). One hundred and fourteen girls, ages 14-18 (15.97 +/- .7), enrolled in high school physical education classes, were measured for calcaneus QUS (stiffness index score), height, weight, current calcium intake from 2-3 day food records, and estimated total hours spent in physical activity from kindergarten to present. Cumulative physical activity hours were separated into two classifications (according to their estimated strain from ground reaction force): moderate to high-impact activities and low to no-impact activities. Pearson correlations between stiffness index (SI) and age, height, weight, current calcium intake, and hours spent in moderate to high-impact versus low to no-impact activities indicated a positive relationships between SI and weight (r = .259, p = .005), current calcium intake (r = .286, p = .002), and hours spent in moderate to high-impact activities (r = .451, p < .001). Multiple regression between SI and the above independent variables indicated that collectively, hours spent in moderate to high-impact activities, current calcium intake, and weight (r (2) = .363, p = <.001) significantly predicted SI. Our data indicate that moderate to high-impact activities, current calcium intake, and weight positively influence bone properties of the calcaneus in adolescent girls.
Araujo, Thaís L S; Borges, Julio Cesar; Ramos, Carlos H; Meyer-Fernandes, José Roberto; Oliveira Júnior, Reinaldo S; Pascutti, Pedro G; Foguel, Debora; Palhano, Fernando L
2014-05-13
We investigated the folding of the 70 kDa human cytosolic inducible protein (Hsp70) in vitro using high hydrostatic pressure as a denaturing agent. We followed the structural changes in Hsp70 induced by high hydrostatic pressure using tryptophan fluorescence, molecular dynamics, circular dichroism, high-performance liquid chromatography gel filtration, dynamic light scattering, ATPase activity, and chaperone activity. Although monomeric, Hsp70 is very sensitive to hydrostatic pressure; after pressure had been removed, the protein did not return to its native sate but instead formed oligomeric species that lost chaperone activity but retained ATPase activity.
Jin, Yingli; Liu, Shuping; Ma, Qingshan; Xiao, Dong; Chen, Li
2017-01-05
High glucose concentration can induce injury of podocytes and berberine has a potent activity against diabetic nephropathy. However, whether and how berberine can inhibit high glucose-mediated injury of podocytes have not been clarified. This study tested the effect of berberine on high glucose-mediated apoptosis and the AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) activation and autophagy in podocytes. The results indicated that berberine significantly mitigated high glucose-decreased cell viability, and nephrin and podocin expression as well as apoptosis in mouse podocytes. Berberine significantly increased the AMPK activation and mitigated high glucose and/or the AMPK inhibitor, compound C-mediated mTOR activation and apoptosis in podocytes. Berberine significantly enhanced the AMPK activation and protected from high glucose-induced apoptosis in the AMPK-silencing podocytes. Furthermore, berberine significantly increased the high glucose-elevated Unc-51-like autophagy-activating kinase 1 (ULK1) S317/S555 phosphorylation, Beclin-1 expression, the ratios of LC3II to LC3I expression and the numbers of autophagosomes, but reduced ULK1 S757 phosphorylation in podocytes. In addition, berberine significantly attenuated compound C-mediated inhibition of autophagy in podocytes. The protective effect of berberine on high glucose-induced podocyte apoptosis was significantly mitigated by pre-treatment with 3-methyladenine or bafilomycin A1. Collectively, berberine enhanced autophagy and protected from high glucose-induced injury in podocytes by promoting the AMPK activation. Our findings may provide new insights into the molecular mechanisms underlying the anti-diabetic nephropathy effect of berberine and may aid in design of new therapies for intervention of diabetic nephropathy. Copyright © 2016 Elsevier B.V. All rights reserved.
Kantomaa, Marko T.; Tikanmäki, Marjaana; Kankaanpää, Anna; Vääräsmäki, Marja; Sipola-Leppänen, Marika; Ekelund, Ulf; Hakonen, Harto; Järvelin, Marjo-Riitta; Kajantie, Eero; Tammelin, Tuija H.
2016-01-01
This study examined the association of education level with objectively measured physical activity and sedentary time in young adults. Data from the Finnish ESTER study (2009–2011) (n = 538) was used to examine the association between educational attainment and different subcomponents of physical activity and sedentary time measured using hip-worn accelerometers (ActiGraph GT1M) for seven consecutive days. Overall physical activity, moderate-to-vigorous physical activity (MVPA), light-intensity physical activity and sedentary time were calculated separately for weekdays and weekend days. A latent profile analysis was conducted to identify the different profiles of sedentary time and the subcomponents of physical activity. The educational differences in accelerometer-measured physical activity and sedentary time varied according to the subcomponents of physical activity, and between weekdays and weekend days. A high education level was associated with high MVPA during weekdays and weekend days in both sexes, high sedentary time during weekdays in both sexes, and a low amount of light-intensity physical activity during weekdays in males and during weekdays and weekend days in females. The results indicate different challenges related to unhealthy behaviours in young adults with low and high education: low education is associated with a lack of MVPA, whereas high education is associated with a lack of light-intensity physical activity and high sedentary time especially during weekdays. PMID:27403958
Katz, Ben; Minke, Baruch
2012-01-01
Drosophila photoreceptor cells use the ubiquitous G-protein-mediated phospholipase C (PLC) cascade to achieve ultimate single photon sensitivity. This is manifested in the single photon responses (quantum bumps). In photoreceptor cells, dark activation of Gqα molecules occurs spontaneously and produces unitary dark events (dark bumps). A high rate of spontaneous Gqα activation and dark bump production potentially hampers single photon detection. We found that in wild type flies the in vivo rate of spontaneous Gqα activation is very high. Nevertheless, this high rate is not manifested in a substantially high rate of dark bumps. Therefore, it is unclear how phototransduction suppresses dark bump production, arising from spontaneous Gqα activation, while still maintaining high-fidelity representation of single photons. In this study we show that reduced PLC catalytic activity selectively suppressed production of dark bumps but not light-induced bumps. Manipulations of PLC activity using PLC mutant flies and Ca2+ modulations revealed that a critical level of PLC activity is required to induce bump production. The required minimal level of PLC activity, selectively suppressed random production of single Gqα-activated dark bumps despite a high rate of spontaneous Gqα activation. This minimal PLC activity level is reliably obtained by photon induced synchronized activation of several neighboring Gqα molecules activating several PLC molecules, but not by random activation of single Gqα molecules. We thus demonstrate how a G-protein-mediated transduction system, with PLC as its target, selectively suppresses its intrinsic noise while preserving reliable signaling. PMID:22357856
Highly Stable and Active Catalyst for Sabatier Reactions
NASA Technical Reports Server (NTRS)
Hu, Jianli; Brooks, Kriston P.
2012-01-01
Highly active Ru/TiO2 catalysts for Sabatier reaction have been developed. The catalysts have shown to be stable under repeated shutting down/startup conditions. When the Ru/TiO2 catalyst is coated on the engineered substrate Fe-CrAlY felt, activity enhancement is more than doubled when compared with an identically prepared engineered catalyst made from commercial Degussa catalyst. Also, bimetallic Ru-Rh/TiO2 catalysts show high activity at high throughput.
Activation of lipoprotein lipase by lipoprotein fractions of human serum.
Bier, D M; Havel, R J
1970-11-01
Triglycerides in fat emulsions are hydrolyzed by lipoprotein lipase only when they are "activated" by serum lipoproteins. The contribution of different lipoprotein fractions to hydrolysis of triglycerides in soybean oil emulsion was assessed by determining the quantity of lipoprotein fraction required to give half-maximal hydrolysis. Most of the activator property of whole serum from normolipidemic, postabsorptive subjects was in high density lipoproteins. Low density lipoproteins and serum from which all lipoprotein classes were removed had little or no activity. Also, little activator was present in guinea pig serum or in very low density poor serum from an individual with lecithin:cholesterol acyltransferase deficiency, both of which are deficient in high density lipoproteins. Human very low density lipoproteins are potent activators and are much more active than predicted from their content of high density lipoprotein-protein. Per unit weight of protein, very low density lipoproteins had 13 times the activity of high density lipoproteins. These observations suggest that one or more of the major apoproteins of very low density lipoproteins, present as a minor constituent of high density lipoproteins, may be required for the activation process.
High salt reduces the activation of IL-4- and IL-13-stimulated macrophages.
Binger, Katrina J; Gebhardt, Matthias; Heinig, Matthias; Rintisch, Carola; Schroeder, Agnes; Neuhofer, Wolfgang; Hilgers, Karl; Manzel, Arndt; Schwartz, Christian; Kleinewietfeld, Markus; Voelkl, Jakob; Schatz, Valentin; Linker, Ralf A; Lang, Florian; Voehringer, David; Wright, Mark D; Hubner, Norbert; Dechend, Ralf; Jantsch, Jonathan; Titze, Jens; Müller, Dominik N
2015-11-02
A high intake of dietary salt (NaCl) has been implicated in the development of hypertension, chronic inflammation, and autoimmune diseases. We have recently shown that salt has a proinflammatory effect and boosts the activation of Th17 cells and the activation of classical, LPS-induced macrophages (M1). Here, we examined how the activation of alternative (M2) macrophages is affected by salt. In stark contrast to Th17 cells and M1 macrophages, high salt blunted the alternative activation of BM-derived mouse macrophages stimulated with IL-4 and IL-13, M(IL-4+IL-13) macrophages. Salt-induced reduction of M(IL-4+IL-13) activation was not associated with increased polarization toward a proinflammatory M1 phenotype. In vitro, high salt decreased the ability of M(IL-4+IL-13) macrophages to suppress effector T cell proliferation. Moreover, mice fed a high salt diet exhibited reduced M2 activation following chitin injection and delayed wound healing compared with control animals. We further identified a high salt-induced reduction in glycolysis and mitochondrial metabolic output, coupled with blunted AKT and mTOR signaling, which indicates a mechanism by which NaCl inhibits full M2 macrophage activation. Collectively, this study provides evidence that high salt reduces noninflammatory innate immune cell activation and may thus lead to an overall imbalance in immune homeostasis.
Multi-frequency localization of aberrant brain activity in autism spectrum disorder.
Xiang, Jing; Korostenskaja, Milena; Molloy, Cynthia; deGrauw, Xinyao; Leiken, Kimberly; Gilman, Carley; Meinzen-Derr, Jareen; Fujiwara, Hisako; Rose, Douglas F; Mitchell, Terry; Murray, Donna S
2016-01-01
The abnormality of intrinsic brain activity in autism spectrum disorders (ASDs) is still inconclusive. Contradictory results have been found pointing towards hyper-activity or hypo-activity in various brain regions. The present research aims to investigate the spatial and spectral signatures of aberrant brain activity in an unprecedented frequency range of 1-2884 Hz at source levels in ASD using newly developed methods. Seven ASD subjects and age- and gender-matched controls were studied using a high-sampling rate magnetoencephalography (MEG) system. Brain activity in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low gamma (30-55 Hz), high gamma (65-90 Hz), ripples (90-200 Hz), high-frequency oscillations (HFOs, 200-1000 Hz), and very high-frequency oscillations (VHFOs, 1000-2884 Hz) was volumetrically localized and measured using wavelet and beamforming. In comparison to controls, ASD subjects had significantly higher odds of alpha activity (8-12 Hz) in the sensorimotor cortex (mu rhythm), and generally high-frequency activity (90-2884 Hz) in the frontal cortex. The source power of HFOs (200-1000 Hz) in the frontal cortex in ASD was significantly elevated as compared with controls. The results suggest that ASD has significantly altered intrinsic brain activity in both low- and high-frequency ranges. Increased intrinsic high-frequency activity in the frontal cortex may play a key role in ASD. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Liu, Tao; Li, Xianfeng; Xu, Chi; Zhang, Huamin
2017-02-08
Vanadium flow batteries (VFBs) have received high attention for large-scale energy storage due to their advantages of flexibility design, long cycle life, high efficiency, and high safety. However, commercial progress of VFBs has so far been limited by its high cost induced by its low power density. Ultrathin carbon paper is believed to be a very promising electrode for VFB because it illustrates super-low ohmic polarization, however, is limited by its low electrocatalytic activity. In this paper, a kind of carbon paper (CP) with super-high electrocatalytic activity was fabricated via a universal and simple CO 2 activation method. The porosity and oxygen functional groups can be easily tuned via this method. The charge transfer resistance (denoting the electrochemical polarization) of a VFB with CP electrode after CO 2 activation decreased dramatically from 970 to 120 mΩcm 2 . Accordingly, the energy efficiency of a VFB with activated carbon paper as the electrode increased by 13% as compared to one without activation and reaches nearly 80% when the current density is 140 mAcm -2 . This paper provides an effective way to prepare high-performance porous carbon electrodes for VFBs and even for other battery systems.
Chu, Anne H Y; Moy, F M
2014-03-01
Metabolic syndrome is a highly prevalent health problem within the adult population in developing countries. We aimed to study the association of physical activity levels and metabolic risk factors among Malay adults in Malaysia. Cross-sectional. Body mass index, waist circumference, and systolic/diastolic blood pressure, fasting blood glucose, fasting triglyceride and high-density lipoprotein cholesterol levels were measured in 686 Malay participants (aged 35-74 years). Self-reported physical activity was obtained with the validated International Physical Activity Questionnaire (Malay version) and categorized into low, moderate or high activity levels. Individuals who were classified as overweight and obese predominated (65.6%). On the basis of the modified NCEP ATP III criteria, metabolic syndrome was diagnosed in 31.9% of all participants, of whom 46.1% were men and 53.9% were women. The prevalence of metabolic syndrome among participants with low, moderate or high activity levels was 13.3%, 11.7% and 7.0%, respectively (p<0.001). Statistically significant negative associations were found between a number of metabolic risk factors and activity categories (p<0.05). The odds ratios for metabolic syndrome in the moderate and high activity categories were 0.42 (95% CI: 0.27-0.65) and 0.52 (95% CI: 0.35-0.76), respectively, adjusted for gender. Moderate and high activity levels were each associated with reduced odds for metabolic syndrome independent of gender. Although a slightly lower prevalence of metabolic syndrome was associated with high activity than with moderate activity, potential health benefits were observed when moderate activity was performed. Copyright © 2013 Sports Medicine Australia. All rights reserved.
NASA Astrophysics Data System (ADS)
Wu, Jianping; Lu, Fei; Zou, Kai; Yan, Hong; Wan, Min; Kuang, Yan; Zhou, Yanqing
2018-03-01
An ultra-high angular velocity and minor-caliber high-precision stably control technology application for active-optics image-motion compensation, is put forward innovatively in this paper. The image blur problem due to several 100°/s high-velocity relative motion between imaging system and target is theoretically analyzed. The velocity match model of detection system and active optics compensation system is built, and active optics image motion compensation platform experiment parameters are designed. Several 100°/s high-velocity high-precision control optics compensation technology is studied and implemented. The relative motion velocity is up to 250°/s, and image motion amplitude is more than 20 pixel. After the active optics compensation, motion blur is less than one pixel. The bottleneck technology of ultra-high angular velocity and long exposure time in searching and infrared detection system is successfully broke through.
Pedersen-Bjergaard, Ulrik; Thomsen, Carsten E; Høgenhaven, Hans; Smed, Annelise; Kjaer, Troels W; Holst, Jens J; Dela, Flemming; Hilsted, Linda; Frandsen, Erik; Pramming, Stig; Thorsteinsson, Birger
2008-03-01
In type 1 diabetes increased risk of severe hypoglycaemia is associated with high angiotensin-converting enzyme (ACE) activity. We tested in healthy humans the hypothesis that this association is explained by the reduced ability of subjects with high ACE activity to maintain normal cognitive function during hypoglycaemia. Sixteen healthy volunteers selected by either particularly high or low serum ACE activity were subjected to hypoglycaemia (plasma glucose 2.7 mmol/L). Cognitive function was assessed by choice reaction tests. Despite a similar hypoglycaemic stimulus in the two groups, only the group with high ACE activity showed significant deterioration in cognitive performance during hypoglycaemia. In the high ACE group mean reaction time (MRT) in the most complex choice reaction task was prolonged and error rate (ER) was increased in contrast to the low ACE group. The total hypoglycaemic symptom response was greater in the high ACE group than in the low ACE group (p=0.031). There were no differences in responses of counterregulatory hormones or in concentrations of substrates between the groups. Healthy humans with high ACE activity are more susceptible to cognitive dysfunction and report higher symptom scores during mild hypoglycaemia than subjects with low ACE activity.
Non-invasive detection of language-related prefrontal high gamma band activity with beamforming MEG.
Hashimoto, Hiroaki; Hasegawa, Yuka; Araki, Toshihiko; Sugata, Hisato; Yanagisawa, Takufumi; Yorifuji, Shiro; Hirata, Masayuki
2017-10-27
High gamma band (>50 Hz) activity is a key oscillatory phenomenon of brain activation. However, there has not been a non-invasive method established to detect language-related high gamma band activity. We used a 160-channel whole-head magnetoencephalography (MEG) system equipped with superconducting quantum interference device (SQUID) gradiometers to non-invasively investigate neuromagnetic activities during silent reading and verb generation tasks in 15 healthy participants. Individual data were divided into alpha (8-13 Hz), beta (13-25 Hz), low gamma (25-50 Hz), and high gamma (50-100 Hz) bands and analysed with the beamformer method. The time window was consecutively moved. Group analysis was performed to delineate common areas of brain activation. In the verb generation task, transient power increases in the high gamma band appeared in the left middle frontal gyrus (MFG) at the 550-750 ms post-stimulus window. We set a virtual sensor on the left MFG for time-frequency analysis, and high gamma event-related synchronization (ERS) induced by a verb generation task was demonstrated at 650 ms. In contrast, ERS in the high gamma band was not detected in the silent reading task. Thus, our study successfully non-invasively measured language-related prefrontal high gamma band activity.
ERIC Educational Resources Information Center
Mueller, Ashley L.; Knobloch, Neil A.; Orvis, Kathryn S.
2015-01-01
Active learning can engage high school students to learn science, yet there is limited understanding if active learning can help students learn challenging science concepts such as genetics and biotechnology. This quasi-experimental study explored the effects of active learning compared to passive learning regarding high school students'…
NASA Astrophysics Data System (ADS)
Gao, Zhiyong; Liu, Xiao; Chang, Jiuli; Wu, Dapeng; Xu, Fang; Zhang, Lingcui; Du, Weimin; Jiang, Kai
2017-01-01
Graphene incorporated, N doped activated carbons (GNACs) are synthesized by alkali activation of graphene-polypyrrole composite (G-PPy) at different temperatures for application as electrode materials of supercapacitors. Under optimal activation temperature of 700 °C, the resultant samples, labeled as GNAC700, owns hierarchically porous texture with high specific surface area and efficient ions diffusion channels, N, O functionalized surface with apparent pseudocapacitance contribution and high wettability, thus can deliver a moderate capacitance, a high rate capability and a good cycleability when used as supercapacitor electrode. Additionally, the GNAC700 electrode demonstrates high catalytic activity for the redox reaction of pyrocatechol/o-quinone pair in H2SO4 electrolyte, thus enables a high pseudocapacitance from electrolyte. Under optimal pyrocatechol concentration in H2SO4 electrolyte, the electrode capacitance of GNAC700 increases by over 4 folds to 512 F g-1 at 1 A g-1, an excellent cycleability is also achieved simultaneously. Pyridinic- N is deemed to be responsible for the high catalytic activity. This work provides a promising strategy to ameliorate the capacitive performances of supercapacitors via the synergistic interaction between redox-active electrolyte and catalytic electrodes.
Chiu, Chen-Yuan; Chan, Im-Lam; Yang, Tsung-Han; Liu, Shing-Hwa; Chiang, Meng-Tsan
2015-03-25
This study investigated the role of chitosan in lipogenesis in high-fat diet-induced obese rats. The lipogenesis-associated genes and their upstream regulatory proteins were explored. Diet supplementation of chitosan efficiently decreased the increased weights in body, livers, and adipose tissues in high-fat diet-fed rats. Chitosan supplementation significantly raised the lipolysis rate; attenuated the adipocyte hypertrophy, triglyceride accumulation, and lipoprotein lipase activity in epididymal adipose tissues; and decreased hepatic enzyme activities of lipid biosynthesis. Chitosan supplementation significantly activated adenosine monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation and attenuated high-fat diet-induced protein expressions of lipogenic transcription factors (PPAR-γ and SREBP1c) in livers and adipose tissues. Moreover, chitosan supplementation significantly inhibited the expressions of downstream lipogenic genes (FAS, HMGCR, FATP1, and FABP4) in livers and adipose tissues of high-fat diet-fed rats. These results demonstrate for the first time that chitosan supplementation alleviates high-fat diet-enhanced lipogenesis in rats via AMPK activation and lipogenesis-associated gene inhibition.
Social capital and physical activity among Croatian high school students.
Novak, D; Doubova, S V; Kawachi, I
2016-06-01
To examine factors associated with regular physical activity in Croatian adolescents. A cross-sectional survey among high school students was carried out in the 2013/14 school year. A survey was conducted among 33 high schools in Zagreb City, Croatia. Participants were students aged 17-18 years. The dependent variables were regular moderate to vigorous physical activity (MVPA) and overall physical activity measured by the short version of International Physical Activity Questionnaire and defined as 60 min or more of daily physical activity. The independent variables included family, neighborhood, and high school social capital. Other study covariates included: socio-economic status, self-rated health, psychological distress and nutritional status. The associations between physical activity and social capital variables were assessed separately for boys and girls through multiple logistic regression and inverse probability weighting in order to correct for missing data bias. A total of 1689 boys and 1739 girls responded to the survey. A higher percentage of boys reported performing regular vigorous and moderate physical activity (59.4%) and overall physical activity (83.4%), comparing with the girls (35.4% and 70%, respectively). For boys, high family social capital and high informal social control were associated with increased odds of regular MVPA (1.49, 95%CI: 1.18 - 1.90 and 1.26, 95%CI: 1.02 - 1.56, respectively), compared to those with low social capital. For girls, high informal social control was associated with regular overall physical activity (OR 1.38, 95% CI: 1.09 - 1.76). High social capital is associated with regular MVPA in boys and regular overall activity in girls. Intervention and policies that leverage community social capital might serve as an avenue for promotion of physical activity in youth. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Yamada, Tsuyoshi; Kanda, Yutaka; Takayama, Makoto; Hashimoto, Akitoshi; Sugihara, Tsutomu; Satoh-Kubota, Ai; Suzuki-Takanami, Eri; Yano, Keiichi; Iida, Shigeru; Satoh, Mitsuo
2016-01-01
The structure of the N-linked oligosaccharides attached to antithrombin (AT) has been shown to affect its anticoagulant activity and pharmacokinetics. Human AT has biantennary complex-type oligosaccharides with the unique feature of lacking a core fucose, which affects its biological activities by changing its heparin-binding affinity. In human plasma, AT circulates as a mixture of the α-form bearing four oligosaccharides and the β-form lacking an oligosaccharide at Asn135. However, it remains unclear how the immature high-mannose-type oligosaccharides produced by mammalian cells affect biological activities of AT. Here, we succeeded in directly comparing the activities between the high-mannose and complex types. Interestingly, although there were no substantial differences in thrombin inhibitory activity, the high-mannose type showed higher heparin-binding affinity. The anticoagulant activities were increased by heparin and correlated with the heparin-binding affinity, resulting in the strongest anticoagulant activity being displayed in the β-form with the high-mannose type. In pharmacokinetic profiling, the high-mannose type showed a much shorter plasma half-life than the complex type. The β-form was found to have a prolonged plasma half-life compared with the α-form for the high-mannose type; conversely, the α-form showed a longer half-life than the β-form for the complex-type. The present study highlights that AT physiological activities are strictly controlled not only by a core fucose at the reducing end but also by the high-mannose-type structures at the nonreducing end. The β-form with the immature high-mannose type appears to function as a more potent anticoagulant than the AT typically found in human plasma, once it emerges in the blood. PMID:26747427
Yamada, Tsuyoshi; Kanda, Yutaka; Takayama, Makoto; Hashimoto, Akitoshi; Sugihara, Tsutomu; Satoh-Kubota, Ai; Suzuki-Takanami, Eri; Yano, Keiichi; Iida, Shigeru; Satoh, Mitsuo
2016-05-01
The structure of the N-linked oligosaccharides attached to antithrombin (AT) has been shown to affect its anticoagulant activity and pharmacokinetics. Human AT has biantennary complex-type oligosaccharides with the unique feature of lacking a core fucose, which affects its biological activities by changing its heparin-binding affinity. In human plasma, AT circulates as a mixture of the α-form bearing four oligosaccharides and the β-form lacking an oligosaccharide at Asn135. However, it remains unclear how the immature high-mannose-type oligosaccharides produced by mammalian cells affect biological activities of AT. Here, we succeeded in directly comparing the activities between the high-mannose and complex types. Interestingly, although there were no substantial differences in thrombin inhibitory activity, the high-mannose type showed higher heparin-binding affinity. The anticoagulant activities were increased by heparin and correlated with the heparin-binding affinity, resulting in the strongest anticoagulant activity being displayed in the β-form with the high-mannose type. In pharmacokinetic profiling, the high-mannose type showed a much shorter plasma half-life than the complex type. The β-form was found to have a prolonged plasma half-life compared with the α-form for the high-mannose type; conversely, the α-form showed a longer half-life than the β-form for the complex-type. The present study highlights that AT physiological activities are strictly controlled not only by a core fucose at the reducing end but also by the high-mannose-type structures at the nonreducing end. The β-form with the immature high-mannose type appears to function as a more potent anticoagulant than the AT typically found in human plasma, once it emerges in the blood. © The Author 2016. Published by Oxford University Press.
Dosch, Alessandra; Rochat, Lucien; Ghisletta, Paolo; Favez, Nicolas; Van der Linden, Martial
2016-11-01
This study explored the role of psychological trait factors in sexual desire and sexual activity. In particular, it investigated how these factors may contribute to maintaining a balance between motivational aspects and self-control abilities, as both have been considered important in relation to adaptive sexuality. Moreover, the study explored the relationship between sexual desire, activity, and satisfaction. Participants completed questionnaires assessing sexual desire (dyadic, solitary), sexual activity (with a partner, alone), sexual satisfaction, approach and avoidance motivation, attachment, self-control, sensation seeking, and mindfulness. Cluster analyses, based on participants' level of sexual desire and sexual activity, highlighted three distinct profiles for each gender related to different types of psychological functioning: (a) participants with high dyadic sexual desire and activity were the most sexually satisfied, showed optimal psychological functioning, and were characterized by a balance between motivational tendencies to seek positive rewards and self-control abilities (high approach motivation, secure attachment, high self-control, high mindfulness); (b) participants with high dyadic and solitary sexual desire and activity were moderately satisfied and showed a type of psychological functioning predominantly characterized by impulsivity (an overly high motivation to obtain rewards in women, and low self-control in men); (c) participants with low dyadic sexual desire and activity were the least sexually satisfied and were characterized by high motivation to avoid negative consequences and low self-control (high avoidance motivation, insecure attachment, and poor mindfulness). These results shed further light on how fundamental psychological factors contribute to explain the individual variability in sexual desire, activity, and satisfaction.
Oxidative stress plays a role in high glucose-induced activation of pancreatic stellate cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ryu, Gyeong Ryul; Lee, Esder; Chun, Hyun-Ji
Highlights: •High glucose increased production of reactive oxygen species in cultured pancreatic stellate cells. •High glucose facilitated the activation of these cells. •Antioxidant treatment attenuated high glucose-induced activation of these cells. -- Abstract: The activation of pancreatic stellate cells (PSCs) is thought to be a potential mechanism underlying islet fibrosis, which may contribute to progressive β-cell failure in type 2 diabetes. Recently, we demonstrated that antioxidants reduced islet fibrosis in an animal model of type 2 diabetes. However, there is no in vitro study demonstrating that high glucose itself can induce oxidative stress in PSCs. Thus, PSCs were isolated andmore » cultured from Sprague Dawley rats, and treated with high glucose for 72 h. High glucose increased the production of reactive oxygen species. When treated with high glucose, freshly isolated PSCs exhibited myofibroblastic transformation. During early culture (passage 1), PSCs treated with high glucose contained an increased number of α-smooth muscle actin-positive cells. During late culture (passages 2–5), PSCs treated with high glucose exhibited increases in cell proliferation, the expression of fibronectin and connective tissue growth factor, release of interleukin-6, transforming growth factor-β and collagen, and cell migration. Finally, the treatment of PSCs with high glucose and antioxidants attenuated these changes. In conclusion, we demonstrated that high glucose increased oxidative stress in primary rat PSCs, thereby facilitating the activation of these cells, while antioxidant treatment attenuated high glucose-induced PSC activation.« less
Cates, Benjamin; Sim, Taeyong; Heo, Hyun Mu; Kim, Bori; Kim, Hyunggun; Mun, Joung Hwan
2018-01-01
In order to overcome the current limitations in current threshold-based and machine learning-based fall detectors, an insole system and novel fall classification model were created. Because high-acceleration activities have a high risk for falls, and because of the potential damage that is associated with falls during high-acceleration activities, four low-acceleration activities, four high-acceleration activities, and eight types of high-acceleration falls were performed by twenty young male subjects. Encompassing a total of 800 falls and 320 min of activities of daily life (ADLs), the created Support Vector Machine model’s Leave-One-Out cross-validation provides a fall detection sensitivity (0.996), specificity (1.000), and accuracy (0.999). These classification results are similar or superior to other fall detection models in the literature, while also including high-acceleration ADLs to challenge the classification model, and simultaneously reducing the burden that is associated with wearable sensors and increasing user comfort by inserting the insole system into the shoe. PMID:29673165
Kirac, Deniz; Ozden, Inci; Yildirim, Alper; Genç, Ece
2009-04-01
The aim of the present study was to investigate whether high fat consumption changes the effects of stress on both motor activity performance, striatal and cortical dopamine and serotonin metabolites in rats. The animals were fed either with high fat or standard diet for 4 weeks. Restraint stress lasting for 15 min at +4 degrees C was applied daily to stress-exposed groups. Motor activity performance was measured weekly by using motor activity monitoring systems. At the end of the study, homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) levels of the striatum and cerebral cortex were measured by HPLCEC. It was observed that restraint stress increased locomotor activity and high-fat diet prevented this effect. Stress and high-fat intake had an additive decreasing effect on striatal HVA levels. 5-HIAA levels, on the other hand, were lower in both high fat and high fat + stress groups compared to the stress group. These results suggest that high-fat intake differentially affected the stress response on striatal dopaminergic and serotonergic neurons in rat brain regions studied and this may be related to the effects observed in motor activity performance.
Highly dispersed buckybowls as model carbocatalysts for C–H bond activation
Soykal, I. Ilgaz; Wang, Hui; Park, Jewook; ...
2015-03-19
Buckybowl fractions dispersed on mesoporous silica constitute an ideal model for studying the catalysis of graphitic forms of carbon since the dispersed carbon nanostructures contain a high ratio of edge defects and curvature induced by non-six-membered rings. Dispersion of the active centers on an easily accessible high surface area material allowed for high density of surface active sites associated with oxygenated structures. This report illustrates a facile method of creating model polycyclic aromatic nano-structures that are not only active for alkane C-H bond activation and oxidative dehydrogenation but also can be practical catalysts to be eventually used in industry.
Dishman, Rod K; Saunders, Ruth P; Motl, Robert W; Dowda, Marsha; Pate, Russell R
2009-05-01
To test whether self-efficacy for overcoming barriers to physical activity has direct, indirect (i.e., mediated), or moderating relations with naturally occurring change in perceived social support and declines in physical activity during high school. Latent growth modeling was used with measures completed in the 8th, 9th, and 12th grades by a cohort of 195 Black and White girls. Self-efficacy was stable and moderated the relation between changes in physical activity and perceived social support. Girls who maintained a perception of strong social support had less of a decline in physical activity if they also had high self-efficacy. However, girls having high self-efficacy had a greater decline in physical activity if they perceived declines in social support. Randomized controlled trials of physical activity interventions based on social cognitive theory should consider that the influence of girls' perceptions of social support on their physical activity may differ according to their efficacy beliefs about barriers to physical activity.
Calamari, L; Gobbi, L; Russo, F; Cappelli, F Piccioli
2015-08-01
The main objective of this experiment was to study the γ-glutamyl transferase (GGT) activity in milk during lactation and its relationship with metabolic status of dairy cows, milk yield, milk composition, and cheesemaking properties. The study was performed in a tied stall barn and involved 20 lactations from 12 healthy multiparous Italian Friesian dairy cows. During lactation starting at d 10, milk samples were collected weekly and analyzed for composition, somatic cells count, titratable acidity, and milk coagulation properties. The GGT activity was measured in defatted samples. Blood samples were collected weekly to assess biochemical indicators related to energy, protein, and mineral metabolism, markers of inflammation and some enzyme activities. The lactations of each cow were retrospectively categorized into 2 groups according to their milk GGT activity value through lactation. A median value of GGT activity in the milk of all lactations was calculated (3,045 U/L), and 10 lactations with lower GGT activity were classified as low while 10 lactations with greater GGT activity were classified as high. The average value of milk GGT activity during lactation was 3,863 and 3,024 U/L for high and low, respectively. The GGT activity decreased in early lactation and reached minimum values in the second month (3,289 and 2,355 U/L for high and low, respectively). Thereafter GGT activity increased progressively, reaching values in late lactation of 4,511 and 3,540 U/L in high and low, respectively. On average, milk yield was 40.81 and 42.76 kg/d in high and low, respectively, and a negative partial correlation with milk GGT activity was observed. A greater milk protein concentration was observed in high (3.39%) compared with low (3.18%), and a positive partial correlation with milk GGT activity was observed. Greater titratable acidity in high than that in low (3.75 vs. 3.45 degrees Soxhlet-Henkel/50 mL, respectively) was also observed. Plasma glucose was greater in cows of high than in low group, while plasma urea was lower in the high than in the low group. No relationship between plasma GGT and milk GGT activity was observed. Our results show an important effect of lactation stage on milk GGT activity. The individual effect observed from consecutive lactations and the relationship between milk GGT activity and milk protein concentration in healthy cows could open prospects for GGT as a future tool in improving milk protein content.
Wheel-running activity modulates circadian organization and the daily rhythm of eating behavior
Pendergast, Julie S.; Branecky, Katrina L.; Huang, Roya; Niswender, Kevin D.; Yamazaki, Shin
2014-01-01
Consumption of high-fat diet acutely alters the daily rhythm of eating behavior and circadian organization (the phase relationship between oscillators in central and peripheral tissues) in mice. Voluntary wheel-running activity counteracts the obesogenic effects of high-fat diet and also modulates circadian rhythms in mice. In this study, we sought to determine whether voluntary wheel-running activity could prevent the proximate effects of high-fat diet consumption on circadian organization and behavioral rhythms in mice. Mice were housed with locked or freely rotating running wheels and fed chow or high-fat diet for 1 week and rhythms of locomotor activity, eating behavior, and molecular timekeeping (PERIOD2::LUCIFERASE luminescence rhythms) in ex vivo tissues were measured. Wheel-running activity delayed the phase of the liver rhythm by 4 h in both chow- and high-fat diet-fed mice. The delayed liver phase was specific to wheel-running activity since an enriched environment without the running wheel did not alter the phase of the liver rhythm. In addition, wheel-running activity modulated the effect of high-fat diet consumption on the daily rhythm of eating behavior. While high-fat diet consumption caused eating events to be more evenly dispersed across the 24 h-day in both locked-wheel and wheel-running mice, the effect of high-fat diet was much less pronounced in wheel-running mice. Together these data demonstrate that wheel-running activity is a salient factor that modulates liver phase and eating behavior rhythms in both chow- and high-fat-diet fed mice. Wheel-running activity in mice is both a source of exercise and a self-motivating, rewarding behavior. Understanding the putative reward-related mechanisms whereby wheel-running activity alters circadian rhythms could have implications for human obesity since palatable food and exercise may modulate similar reward circuits. PMID:24624109
NF-kappa B activation correlates with disease phenotype in Crohn’s disease
Han, Yoo Min; Koh, Jaemoon; Lee, Changhyun; Koh, Seong-Joon; Kim, ByeongGwan; Lee, Kook Lae; Im, Jong Pil; Kim, Joo Sung
2017-01-01
Background/Aims Unregulated activation of nuclear factor-κB (NF-κB) plays a critical role in the pathogenesis of Crohn’s disease. In this study, we investigated the clinical characteristics and disease outcome of Crohn’s disease patients with varying levels of the NF-κB activation. Methods Crohn’s disease patients who underwent surgical bowel resection were divided into two groups, based on the activation status of NF-κB. NF-κB activation was assessed by the immunoreactivity of nuclear NF-κB during immunohistochemical staining of bowel resection specimens. We compared the demographic, clinical and histologic characteristics between groups. Furthermore, the occurrence of reoperation, readmission, and medication change due to disease flare-up were investigated according to NF-κB activation status. Results Among 83 Crohn’s disease patients, 47 (56%) showed high NF-κB activity and 36 (44%) showed low NF-κB activity. Patients with high NF-κB activity had higher frequency of ileocolonic involvement (P = 0.028) and lower frequency of perianal involvement (P = 0.042) relative to those with low NF-κB activity. Total histologic scores were significantly higher in patients with high NF-κB activity than those with low NF-κB activity (P = 0.044). There was no significant difference in the frequency of reoperation, readmission, and medication change in relation to NF-κB activation status. Conclusions Crohn’s disease patients with high NF-κB activation showed specific clinical manifestations of higher frequency of ileocolonic involvement and lower frequency of perianal involvement relative to those with low NF-κB activation. High NF-κB activity was associated with higher histologic scores. However, the NF-κB activity did not affect the outcome and disease course after surgery. PMID:28753650
High carrier activation of Mg ion-implanted GaN by conventional rapid thermal annealing
NASA Astrophysics Data System (ADS)
Niwa, Takaki; Fujii, Takahiro; Oka, Tohru
2017-09-01
A high activation ratio of Mg ion implantation by conventional rapid thermal annealing (RTA) was demonstrated. To obtain the high activation ratio of Mg ion implantation, the dependence of hole concentration on Mg dose was investigated. A maximum hole concentration and a high activation ratio of 2.3% were obtained at a Mg dose of 2.3 × 1014 cm-2 between 9.2 × 1013 and 2.3 × 1015 cm-2. The ratio is, to the best of our knowledge, the highest ever obtained by conventional RTA.
Measurement of actinides and strontium-90 in high activity waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maxwell, S.L. III; Nelson, M.R.
1994-08-01
The reliable measurement of trace radionuclides in high activity waste is important to support waste processing activities at SRS (F and H Area Waste Tanks, Extended Sludge Processing (ESP) and In-Tank precipitation (ITP) processing). Separation techniques are needed to remove high levels of gamma activity and alpha/beta interferences prior to analytical measurement. Using new extraction chromatographic resins from EiChrom Industries, Inc., the SRS Central Laboratory has developed new high speed separation methods that enable measurement of neptunium, thorium, uranium, plutonium, americium and strontium-90 in high activity waste solutions. Small particle size resin and applied vacuum are used to reduce analysismore » times and enhance column performance. Extraction chromatographic resins are easy to use and eliminate the generation of contaminated liquid organic waste.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Won Seok; Chang, Jai Won; Han, Nam Jeong
The role of spleen tyrosine kinase (Syk) in high glucose-induced intracellular signal transduction has yet to be elucidated. We investigated whether Syk is implicated in high glucose-induced transforming growth factor-{beta}1 (TGF-{beta}1) up-regulation in cultured human proximal tubular epithelial cells (HK-2 cell). High glucose increased TGF-{beta}1 gene expression through Syk, extracellular signal-regulated kinase (ERK), AP-1 and NF-{kappa}B. High glucose-induced AP-1 DNA binding activity was decreased by Syk inhibitors and U0126 (an ERK inhibitor). Syk inhibitors suppressed high glucose-induced ERK activation, whereas U0126 had no effect on Syk activation. High glucose-induced NF-{kappa}B DNA binding activity was also decreased by Syk inhibitors. Highmore » glucose increased nuclear translocation of p65 without serine phosphorylation of I{kappa}B{alpha} and without degradation of I{kappa}B{alpha}, but with an increase in tyrosine phosphorylation of I{kappa}B{alpha} that may account for the activation of NF-{kappa}B. Both Syk inhibitors and Syk-siRNA attenuated high glucose-induced I{kappa}B{alpha} tyrosine phosphorylation and p65 nuclear translocation. Depletion of p21-activated kinase 2 (Pak2) by transfection of Pak2-siRNA abolished high glucose-induced Syk activation. In summary, high glucose-induced TGF-{beta}1 gene transcription occurred through Pak2, Syk and subsequent ERK/AP-1 and NF-{kappa}B pathways. This suggests that Syk might be implicated in the diabetic kidney disease.« less
Coombes, R. Hunter; Meek, Edward C.; Dail, Mary Beth; Chambers, Howard W.; Chambers, Janice E.
2016-01-01
The organophosphorus insecticide chlorpyrifos has been widely used. Its active metabolite chlorpyrifos-oxon (CPO) is a potent anticholinesterase and is detoxified by paraoxonase-1 (PON1). PON1 activity is influenced by numerous factors including a Q192R polymorphism. Using forty human blood samples bearing homozygous genotypes and either high or low activity phenotypes (as determined by high concentration assays of paraoxon and diazoxon hydrolysis) the serum PON1 hydrolysis of high (320 μM) and low (178 nM) CPO concentrations was assessed using direct or indirect spectrophotometric methods, respectively. PON1 activity at high CPO concentration reflected the phenotype and genotype differences; subjects with the high activity phenotype and homozygous for the PON1R192 alloform hydrolyzed significantly more CPO than subjects with the low activity phenotype and/or PON1Q192 alloform (High RR=11023±722, Low RR=9467±798, High QQ=8809±672, Low QQ=6030±1015 μmoles CPO hydrolyzed/min/L serum). However, PON1 hydrolysis of CPO at the lower, more environmentally relevant concentration showed no significant differences between the PON1192 genotypes and/or between high and low activity phenotypes (High RR=231±27, Low RR=219±52, High QQ=193±59, Low QQ=185±43 nmoles CPO/min/L serum). Low CPO concentrations were probably not saturating, so PON1 did not display maximal velocity and the PON1 genotype/phenotype might not influence the extent of metabolism at environmental exposures. PMID:25093614
Carbonic anhydrase activity in the red blood cells of sea level and high altitude natives.
Gamboa, J; Caceda, R; Gamboa, A; Monge-C, C
2000-01-01
Red blood cell carbonic anhydrase (CA) activity has not been studied in high altitude natives. Because CA is an intraerythocytic enzyme and high altitude natives are polycythemic, it is important to know if the activity of CA per red cell volume is different from that of their sea level counterparts. Blood was collected from healthy subjects living in Lima (150m) and from twelve subjects from Cerro de Pasco (4330m), and hematocrit and carbonic anhydrase activity were measured. As expected, the high altitude natives had significantly higher hematocrits than the sea level controls (p = 0.0002). No difference in the CA activity per milliliter of red cells was found between the two populations. There was no correlation between the hematocrit and CA activity.
Battery designs with high capacity anode materials and cathode materials
Masarapu, Charan; Anguchamy, Yogesh Kumar; Han, Yongbong; Deng, Haixia; Kumar, Sujeet; Lopez, Herman A.
2017-10-03
Improved high energy capacity designs for lithium ion batteries are described that take advantage of the properties of high specific capacity anode active compositions and high specific capacity cathode active compositions. In particular, specific electrode designs provide for achieving very high energy densities. Furthermore, the complex behavior of the active materials is used advantageously in a radical electrode balancing design that significantly reduced wasted electrode capacity in either electrode when cycling under realistic conditions of moderate to high discharge rates and/or over a reduced depth of discharge.
Jarvie, Jennifer L; Whooley, Mary A; Regan, Mathilda C; Sin, Nancy L; Cohen, Beth E
2014-10-15
Higher levels of physical activity are associated with lower rates of coronary heart disease (CHD). Previous studies have suggested that this is due partly to lower levels of inflammation and insulin resistance. The aim of this study was to determine whether physical activity level was associated with inflammation or insulin resistance during a 5-year period in outpatients with known CHD. A total of 656 participants from the Heart and Soul Study, a prospective cohort study of outpatients with documented CHD, were evaluated. Self-reported physical activity frequency was assessed at baseline and after 5 years of follow-up. Participants were classified as low versus high activity at each visit, yielding 4 physical activity groups: stable low activity, decreasing activity (high at baseline to low at year 5), increasing activity (low at baseline to high at year 5), and stable high activity. Year 5 markers of inflammation (C-reactive protein [CRP], interleukin-6, and fibrinogen) and insulin resistance (insulin, glucose, and glycated hemoglobin) were compared across the 4 activity groups. After 5 years of follow-up, higher activity was associated with lower mean levels of all biomarkers. In the fully adjusted regression models, CRP, interleukin-6, and glucose remained independently associated with physical activity frequency (log CRP, p for trend across activity groups = 0.03; log interleukin-6, p for trend = 0.01; log glucose, p for trend = 0.003). Subjects with stable high activity typically had the lowest levels of biomarkers. In conclusion, in this novel population of outpatients with known CHD followed for 5 years, higher physical activity frequency was independently associated with lower levels of CRP, interleukin-6, and glucose. Copyright © 2014 Elsevier Inc. All rights reserved.
Self-Controlled Feedback Facilitates Motor Learning in Both High and Low Activity Individuals
Fairbrother, Jeffrey T.; Laughlin, David D.; Nguyen, Timothy V.
2012-01-01
The purpose of this study was to determine if high and low activity individuals differed in terms of the effects of self-controlled feedback on the performance and learning of a movement skill. The task consisted of a blindfolded beanbag toss using the non-preferred arm. Participants were pre-screened according to their physical activity level using the International Physical Activity Questionnaire. An equal number of high activity (HA) and low activity (LA) participants were assigned to self-control (SC) and yoked (YK) feedback conditions, creating four groups: Self-Control-High Activity; Self-Control-Low Activity; Yoked-High Activity; and Yoked-Low Activity. SC condition participants were provided feedback whenever they requested it, while YK condition participants received feedback according to a schedule created by their SC counterpart. Results indicated that the SC condition was more accurate than the YK condition during acquisition and transfer phases, and the HA condition was more accurate than the LA condition during all phases of the experiment. A post-training questionnaire indicated that participants in the SC condition asked for feedback mostly after what they perceived to be “good” trials; those in the YK condition indicated that they would have preferred to receive feedback after “good” trials. This study provided further support for the advantages of self-controlled feedback when learning motor skills, additionally showing benefits for both active and less active individuals. The results suggested that the provision of self-controlled feedback to less active learners may be a potential avenue to teaching motor skills necessary to engage in greater amounts of physical activity. PMID:22969745
Wang, Zhen-mei; Li, Hai-xia; Liu, Xiong-feng; He, Ying; Zeng, Han-lai
2015-04-01
Global warming affects both rice (Oryza sativa) yields and grain quality. Rice chalkiness due to high temperature during grain filling would lower the grain quality. The biochemical and molecular mechanisms responsible for the increased occurrence of chalkiness under high temperature are not fully understood. Previous research suggested that cytosolic pyruvate orthophosphate dikinase (cyPPDK, EC 2.7.9.1) in rice modulates carbon metabolism. The objective of this study was to determine the relationship between cyPPDK and high temperature-induced chalkiness. High temperature treatments were applied during the grain filling of two rice cultivars (9311 and TXZ-25) which had different sensitivity of chalkiness to high temperature. Chalkiness was increased significantly under high temperature treatment, especially for TXZ-25. A shortened grain filling duration and a decreased grain weight in both cultivars were caused by high temperature treatment. A reduction in PPDK activities due to high temperature was observed during the middle and late grain filling periods, accompanied by down regulated cyPPDK mRNA and protein levels. The temperature effects on the developmental regulation of PPDK activity were confirmed at transcription, translation and post-translational levels. PPDK activities were insensitive to variation in PPDK levels, suggesting the rapid phosphorylation mechanism of this protein. The two varieties showed similar responses to the high temperature treatment in both PPDK activities and chalkiness. We concluded that high temperature-induced chalkiness was associated with the reduction of PPDK activity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Bláfoss, Rúni; Micheletti, Jéssica K; Sundstrup, Emil; Jakobsen, Markus D; Bay, Hans; Andersen, Lars L
2018-04-01
In spite of the many health-related benefits of regular physical activity, fatiguing work may be a barrier to performing leisure-time physical activity. This study investigates the association between work-related fatigue and the duration of low- and high-intensity leisure-time physical activity in workers with sedentary and physically demanding jobs. From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners from the general working population ( N=10,427) replied to questions about work-related fatigue (predictor) and duration of low- and high-intensity leisure-time physical activity (outcome). Associations were modelled using general linear models controlling for various confounders. Among workers with physically demanding jobs, higher levels of work-related fatigue were associated with gradually lower levels of leisure-time physical activity - for low, moderate and high levels of work-related fatigue the duration of high-intensity leisure-time physical activity was 133 (95% confidence interval (CI) 127-178), 134 (95% CI 109-160) and 113 (95% CI 86-140) min per week, respectively (trend test p<0.001). The duration of high-intensity leisure-time physical activity was lower among older workers (≥50 years) compared to younger workers (<50 years) (132 ± 126 vs 168 ± 150 min per week) ( p<0.0001). The duration of high-intensity leisure-time physical activity gradually decreases with increased work-related fatigue in workers with physically demanding jobs. Older workers perform less high-intensity physical activity than younger workers. Workplaces should consider initiatives to allow workers with physically demanding jobs and older workers to perform physical exercise during working hours and thereby increase physical capacity to meet the job demands.
Vuković, Rosemary; Blažetić, Senka; Oršolić, Ivana; Heffer, Marija; Vari, Sandor G; Gajdoš, Martin; Krivošíková, Zora; Kramárová, Patrícia; Kebis, Anton; Has-Schön, Elizabeta
2014-06-01
To estimate the impact of high fat diet and estrogen deficiency on the oxidative and antioxidative status in the liver of the ovariectomized rats, as well as the ameliorating effect of physical activity or consumption of functional food containing bioactive compounds with antioxidative properties on oxidative damage in the rat liver. The study was conducted from November 2012 to April 2013. Liver oxidative damage was determined by lipid peroxidation levels expressed in terms of thiobarbituric acid reactive substances (TBARS), while liver antioxidative status was determined by catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) activities, and glutathione (GSH) content. Sixty-four female Wistar rats were divided into eight groups: sham operated and ovariectomized rats that received either standard diet, high fat diet, or high fat diet supplemented with cereal selenized onion biscuits or high fat diet together with introduction of physical exercise of animals. High fat diet significantly increased TBARS content in the liver compared to standard diet (P=0.032, P=0.030). Furthermore, high fat diet decreased the activities of CAT, GR, and GST, as well as the content of GSH (P<0.050). GPx activity remained unchanged in all groups. Physical activity and consumption of cereal selenized onion biscuits showed protective effect through increased GR activity in sham operated rats (P=0.026, P=0.009), while in ovariectomized group CAT activity was increased (P=0.018) in rats that received cereal selenized onion biscuits. Feeding rats with high fat diet was accompanied by decreased antioxidative enzyme activities and increased lipid peroxidation. Bioactive compounds of cereal selenized onion biscuits showed potential to attenuate the adverse impact of high fat diet on antioxidative status.
Facilitation of epileptic activity during sleep is mediated by high amplitude slow waves
von Ellenrieder, Nicolás; Ferrari-Marinho, Taissa; Avoli, Massimo; Dubeau, François; Gotman, Jean
2015-01-01
Epileptic discharges in focal epilepsy are frequently activated during non-rapid eye movement sleep. Sleep slow waves are present during this stage and have been shown to include a deactivated (‘down’, hyperpolarized) and an activated state (‘up’, depolarized). The ‘up’ state enhances physiological rhythms, and we hypothesize that sleep slow waves and particularly the ‘up’ state are the specific components of non-rapid eye movement sleep that mediate the activation of epileptic activity. We investigated eight patients with pharmaco-resistant focal epilepsies who underwent combined scalp-intracerebral electroencephalography for diagnostic evaluation. We analysed 259 frontal electroencephalographic channels, and manually marked 442 epileptic spikes and 8487 high frequency oscillations during high amplitude widespread slow waves, and during matched control segments with low amplitude widespread slow waves, non-widespread slow waves or no slow waves selected during the same sleep stages (total duration of slow wave and control segments: 49 min each). During the slow waves, spikes and high frequency oscillations were more frequent than during control segments (79% of spikes during slow waves and 65% of high frequency oscillations, both P ∼ 0). The spike and high frequency oscillation density also increased for higher amplitude slow waves. We compared the density of spikes and high frequency oscillations between the ‘up’ and ‘down’ states. Spike and high frequency oscillation density was highest during the transition from the ‘up’ to the ‘down’ state. Interestingly, high frequency oscillations in channels with normal activity expressed a different peak at the transition from the ‘down’ to the ‘up’ state. These results show that the apparent activation of epileptic discharges by non-rapid eye movement sleep is not a state-dependent phenomenon but is predominantly associated with specific events, the high amplitude widespread slow waves that are frequent, but not continuous, during this state of sleep. Both epileptic spikes and high frequency oscillations do not predominate, like physiological activity, during the ‘up’ state but during the transition from the ‘up’ to the ‘down’ state of the slow wave, a period of high synchronization. Epileptic discharges appear therefore more associated with synchronization than with excitability. Furthermore, high frequency oscillations in channels devoid of epileptic activity peak differently during the slow wave cycle from those in channels with epileptic activity. This property may allow differentiating physiological from pathological high frequency oscillations, a problem that is unresolved until now. PMID:25792528
Sung, Aaron; Garcia, Nathan S.; Gracey, Andrew Y.; German, Donovan P.
2016-01-01
ABSTRACT The intertidal mussel Mytilus californianus is a critical foundation species that is exposed to fluctuations in the environment along tidal- and wave-exposure gradients. We investigated feeding and digestion in mussels under laboratory conditions and across environmental gradients in the field. We assessed whether mussels adopt a rate-maximization (higher ingestion and lower assimilation) or a yield-maximization acquisition (lower ingestion and higher assimilation) strategy under laboratory conditions by measuring feeding physiology and digestive enzyme activities. We used digestive enzyme activity to define resource acquisition strategies in laboratory studies, then measured digestive enzyme activities in three microhabitats at the extreme ends of the tidal- and wave-exposure gradients within a stretch of shore (<20 m) projected sea-ward. Our laboratory results indicated that mussels benefit from a high assimilation efficiency when food concentration is low and have a low assimilation efficiency when food concentration is high. Additionally, enzyme activities of carbohydrases amylase, laminarinase and cellulase were elevated when food concentration was high. The protease trypsin, however, did not increase with increasing food concentration. In field conditions, low-shore mussels surprisingly did not have high enzyme activities. Rather, high-shore mussels exhibited higher cellulase activities than low-shore mussels. Similarly, trypsin activity in the high-shore-wave-sheltered microhabitat was higher than that in high-shore-wave-exposed. As expected, mussels experienced increasing thermal stress as a function of reduced submergence from low to high shore and shelter from wave-splash. Our findings suggest that mussels compensate for limited feeding opportunities and thermal stress by modulating digestive enzyme activities. PMID:27402963
Jiang, Wei; Wang, Ya-Li; Fang, Bai-Shan
2018-05-09
As phenylalanine dehydrogenase (PheDH) plays an important role in the synthesis of chiral drug intermediates and detection of phenylketonuria, it is significant to obtain a PheDH with specific and high activity. Here, a PheDH gene, pdh, encoding a novel BhPheDH with 61.0% similarity to the known PheDH from Microbacterium sp., was obtained. The BhPheDH showed optimal activity at 60 °C and pH 7.0, and it showed better stability in hot environment (40-70 °C) than the PheDH from Nocardia sp. And its activity and thermostability could be significantly increased by sodium salt. After incubation for 2 h in 3 M NaCl at 60 °C, the residual activity of the BhPheDH was found to be 1.8-fold higher than that of the control group (without NaCl). The BhPheDH could tolerate high concentration of ammonium chloride and its activity could be also enhanced by the high concentration of ammonium salts. These characteristics indicate that the BhPheDH possesses better thermostability, ammonium chloride tolerance, halophilic mechanism, and high salt activation. The mechanism of thermostability and high salt tolerance of the BhPheDH was analyzed by molecular dynamics simulation. These results provide useful information about the enzyme with high-temperature activity, thermostability, halophilic mechanism, tolerance to high concentration of ammonium chloride, higher salt activation and enantio-selectivity, and the application of molecular dynamics simulation in analyzing the mechanism of these distinctive characteristics.
Social Cognitive Theory and Physical Activity Among Korean Male High-School Students.
Lee, Chung Gun; Park, Seiyeong; Lee, Seung Hwan; Kim, Hyunwoo; Park, Ji-Won
2018-02-01
The most critical step in developing and implementing effective physical activity interventions is to understand the determinants and correlates of physical activity, and it is strongly suggested that such effort should be based on theories. The purpose of this study is to test the direct, indirect, and total effect of social cognitive theory constructs on physical activity among Korean male high-school students. Three-hundred and forty-one 10th-grade male students were recruited from a private single-sex high school located in Seoul, South Korea. Structural equation modeling was used to test the expected relationships among the latent variables. The proposed model accounted for 42% of the variance in physical activity. Self-efficacy had the strongest total effect on physical activity. Self-efficacy for being physically active was positively associated with physical activity ( p < .01). Self-efficacy also had positive indirect effects on physical activity through perceived benefits ( p < .05) and goal setting ( p < .01). The results of this study indicated that the social cognitive theory is a useful framework to understand physical activity among Korean male adolescents. Physical activity interventions targeting Korean male high-school students should focus on the major sources of efficacy.
Kamarck, T W; Shiffman, S M; Smithline, L; Goodie, J L; Paty, J A; Gnys, M; Jong, J Y
1998-01-01
Ambulatory blood pressure (ABP) may be an independent predictor of cardiovascular endpoints, but little is known about its psychosocial determinants. The acute effects of psychosocial processes on cardiovascular activity during daily life were examined by random-effects regression. Healthy adults (N = 120) were monitored over a 6-day period with ABP monitors and computer-assisted self-report assessments. Task strain, social conflict, and emotional activation were rated following each ABP measurement, as were activity, posture, and other covariates. Results show that blood pressure (BP) and heart rate (HR) were elevated during periods of emotional activation (high negative affect or high arousal). Diastolic BP was lower during periods involving high decisional control, and HR was lower during high-control, low-demand activities. There were substantial individual differences in the effects of psychosocial influences on ambulatory cardiovascular activity. Psychological factors are reliable determinants of ABP, which may account in part for the unique predictive value of ABP.
High School Teaching and College Performance: Looking for Connections
NASA Astrophysics Data System (ADS)
Tai, Robert H.
2006-12-01
How much impact does high school have on college? Are decisions about classroom activities and student work in high school physics associated with student performance in college physics? In our paper, we look at several aspects of high school physics including laboratory experiences, homework activities, and classroom activities and their association with college physics grades. Our results revisit in greater depth and earlier analysis carried out a decade earlier.
Šantl-Temkiv, Tina; Amato, Pierre; Gosewinkel, Ulrich; Thyrhaug, Runar; Charton, Anaïs; Chicot, Benjamin; Finster, Kai; Bratbak, Gunnar; Löndahl, Jakob
2017-10-03
The study of airborne bacteria relies on a sampling strategy that preserves their integrity and in situ physiological state, e.g. viability, cultivability, metabolic activity, and ice-nucleation activity. Because ambient air harbors low concentrations of bacteria, an effective bioaerosol sampler should have a high sampling efficiency and a high airflow. We characterize a high-flow-rate impinger with respect to particle collection and retention efficiencies in the range 0.5-3.0 μm, and we investigated its ability to preserve the physiological state of selected bacterial species and seawater bacterial community in comparison with four commercial bioaerosol samplers. The collection efficiency increased with particle size and the cutoff diameter was between 0.5 and 1 μm. During sampling periods of 120-300 min, the impinger retained the cultivability, metabolic activity, viability, and ice-nucleation activity of investigated bacteria. Field studies in semiurban, high-altitude, and polar environments included periods of low bacterial air concentrations, thus demonstrating the benefits of the impinger's high flow rate. In conclusion, the impinger described here has many advantages compared with other bioaerosol samplers currently on the market: a potential for long sampling time, a high flow rate, a high sampling and retention efficiency, low costs, and applicability for diverse downstream microbiological and molecular analyses.
Madrid, Hector P; Patterson, Malcolm G; Leiva, Pedro I
2015-11-01
Employees can help to improve organizational performance by sharing ideas, suggestions, or concerns about practices, but sometimes they keep silent because of the experience of negative affect. Drawing and expanding on this stream of research, this article builds a theoretical rationale based on core affect and cognitive appraisal theories to describe how differences in affect activation and boundary conditions associated with cognitive rumination and cognitive problem-solving demands can explain employee silence. Results of a diary study conducted with professionals from diverse organizations indicated that within-person low-activated negative core affect increased employee silence when, as an invariant factor, cognitive rumination was high. Furthermore, within-person high-activated negative core affect decreased employee silence when, as an invariant factor, cognitive problem-solving demand was high. Thus, organizations should manage conditions to reduce experiences of low-activated negative core affect because these feelings increase silence in individuals high in rumination. In turn, effective management of experiences of high-activated negative core affect can reduce silence for individuals working under high problem-solving demand situations. (c) 2015 APA, all rights reserved).
How Active Are Teens during Their Out-of-School Time? The View from Chicago. Chapin Hall Issue Brief
ERIC Educational Resources Information Center
Goerge, Robert M.; Cusick, Gretchen Ruth; Guiltinan, Shannon
2009-01-01
This issue brief explores levels of physical activity among high school students in Chicago Public Schools, including participation in sports, informal exercise, and other activities. Latent class analysis was used to classify students' levels of physical activity, revealing low levels of activity among most high school students. Multilevel…
High-intensity erotic visual stimuli de-activate the primary visual cortex in women.
Huynh, Hieu K; Beers, Caroline; Willemsen, Antoon; Lont, Erna; Laan, Ellen; Dierckx, Rudi; Jansen, Monique; Sand, Michael; Weijmar Schultz, Willibrord; Holstege, Gert
2012-06-01
The primary visual cortex, Brodmann's area (BA 17), plays a vital role in basic survival mechanisms in humans. In most neuro-imaging studies in which the volunteers have to watch pictures or movies, the primary visual cortex is similarly activated independent of the content of the pictures or movies. However, in case the volunteers perform demanding non-visual tasks, the primary visual cortex becomes de-activated, although the amount of incoming visual sensory information is the same. Do low- and high-intensity erotic movies, compared to neutral movies, produce similar de-activation of the primary visual cortex? Brain activation/de-activation was studied by Positron Emission Tomography scanning of the brains of 12 healthy heterosexual premenopausal women, aged 18-47, who watched neutral, low- and high-intensity erotic film segments. We measured differences in regional cerebral blood flow (rCBF) in the primary visual cortex during watching neutral, low-intensity erotic, and high-intensity erotic film segments. Watching high-intensity erotic, but not low-intensity erotic movies, compared to neutral movies resulted in strong de-activation of the primary (BA 17) and adjoining parts of the secondary visual cortex. The strong de-activation during watching high-intensity erotic film might represent compensation for the increased blood supply in the brain regions involved in sexual arousal, also because high-intensity erotic movies do not require precise scanning of the visual field, because the impact is clear to the observer. © 2012 International Society for Sexual Medicine.
Association between active commuting and elevated blood pressure in adolescents.
Santana, Fábio da Silva; Palmeira, Aline Cabral; Santos, Marcos André Moura Dos; Farah, Breno Quintella; Souza, Bruna Cadengue Coêlho de; Ritti-Dias, Raphael Mendes
2017-01-01
To analyze the association between active commuting and blood pressure in adolescents. This is a cross-sectional study with high school students from public education network in the state of Pernambuco, Brazil. Data from 6039 students (14 to 19 years) were collected using a questionnaire. "Physically inactive" were considered those who reported not to walk or ride a bicycle to and from school on any day of the past week, and/or those who, regardless of the weekly frequency of practice this type of activity, reported the duration of commuting to school was less than 20 minutes (round trip). The high blood pressure was obtained by Omron HEM 742 equipment. Adolescents with high blood pressure were defined as those with higher blood pressure or equal to the 95th percentile for age, sex and height. Regression logistic analyses were used to assess the association between active commuting and high blood pressure, considering adjustments for the following confounders: sex, age, overweight, total physical activity, socioeconomic level, place of residence. The prevalence of high blood pressure was 7.3%, and 79.3% were considered insufficiently active in commuting. There was an association between high blood pressure and active commuting only among those living in rural areas (OR = 6.498; 95% CI = 1.513-27.900), and the same was not observed among those living in urban areas (OR = 1.113; 95% CI = 0.812-1.526). Active commuting can be considered a protective factor for high blood pressure in adolescents living in rural areas.
Sakuta, Hidenari; Suzuki, Takashi
2006-01-01
We cross-sectionally analyzed the association between duration of physical activity and the presence of selected cardiovascular risk factors in the middle-aged male personnel of the Self-Defense Forces who underwent retirement check-up (n = 974). In a univariate regression analysis, duration of high intensity physical activity but not that of moderate or low intensity physical activity inversely correlated with body mass index (BMI), triglyceride, fasting plasma glucose, white blood cell (WBC) count and systolic blood pressure. No intensity categories of physical activity correlated with total cholesterol. In a multivariate logistic regression analysis adjusted for lifestyle factors and the rank, the odds ratio per 1 h/wk increase in high intensity physical activity was .88 (95% confidence interval (CI) .80-.97; P=.007) for the presence of obesity (BMI 25.0 kg/m2), .88 (95% CI .81-.95; P = .002) for hypertrigly ceridemia, .87 (95% CI .76-.99; P=.034) for type 2 diabetes, and .90 (95% CI .82-.99; P=.037) for hypertension. Neither hypercholesterolemia nor high WBC count (> or = 6,900/microl) was associated with high intensity physical activity. High intensity physical activity inversely correlated with traditional cardiovascular risk factors in the middle-aged men.
Gajewski, Patrick D; Falkenstein, Michael
2015-08-01
Aging is associated with compromised executive control functions. Several lines of evidence point to beneficial effects of physical activity on cognition which indicate that regular physical activity may counteract the age-related decline of some executive functions. Here, we investigate the effects of lifelong physical activity (about 50 years) on interference processing in two matched groups of 20 physically high active and 20 low active healthy older men using event-related potentials (ERPs). In a low interference block of the Stroop task, participants had to indicate the meaning of color-words, while color was either compatible or incompatible with the meaning. In the high interference block, participants were asked to respond according to the ink color of the word and to ignore its meaning. Physically active seniors showed faster reaction times, lower individual variability in reaction times, and higher accuracy compared to low active seniors, particularly in the high interference block. This result was confirmed in the classic paper-and-pencil version of the Stroop task showing higher interference score in the low active than high active individuals. ERPs revealed a shorter latency of the P2 and generally more negative amplitudes of the fronto-central N2 and N450 components in the high active group compared to the low active group. The amount of interference was negatively correlated with objectively measured fitness and self-reported physical activity. The positive effect of physical fitness on interference processing in the behavioral data was related to N2 and N450 amplitudes. Taken together, this suggests that seniors reporting long-term physical activity may exhibit generally enhanced activity in the frontal cortex which enables more efficient interference resolution in the Stroop task. Copyright © 2015 Elsevier Inc. All rights reserved.
Engelen, Lina; Gale, Joanne; Chau, Josephine Y; Hardy, Louise L; Mackey, Martin; Johnson, Nathan; Shirley, Debra; Bauman, Adrian
2017-04-01
To examine the associations of physical activity (PA) and sitting time (sit) with cardio-metabolic diseases. Cross-sectional data from the Australian National Nutrition and Physical Activity Survey 2011-2012 (n=9,435) were used to classify adults into low and high risk groups based on their physical activity and sitting behaviour profiles. Logistic regression models examined associations between low and high risk classifications (high PA-low sit; high PA-high sit; low PA-low sit; low PA-high sit;) and socio-demographic factors, and associations between low and high risk classifications and the prevalence of cardiovascular disease, Type 2 diabetes and metabolic syndrome. These results characterise chronic disease risk based on both physical activity and sitting behaviour. Adults with the highest risk lifestyle behaviour pattern (low PA-high sit) tended to be middle aged, male, at greater social disadvantage, smoke, report fair health, be abdominally obese and employed in administrative and driver occupations. These individuals had a substantially greater risk of cardiovascular disease and metabolic syndrome (OR=1.41, 95% CI 1.13, 1.75; OR= 2.37, 95% CI 1.63, 3.45, respectively). The findings highlight the importance of both sufficient physical activity and low sitting time for cardio-metabolic health. Implications for public health: Primary prevention focus should consider physical activity and reduced sitting time as well as provision of relevant advice for cardio-metabolic health. © 2017 The Authors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, C.; Phillips, M.; Miller, C.
1986-11-05
Charybdotoxim is a high-affinity specific inhibitor of the high-conductance Ca/sup 2 +/-activated K/sup +/ channel found in the plasma membranes of many vertebrate cell types. Using Ca/sup 2 +/-activated K/sup +/ channels reconstituted into planar lipid bilayer membranes as an assay, the authors have purified the toxin from the venom of the scorpion Leiurus quinquestriatus by a two-step procedure involving chromatofocusing on SP-Sephadex, followed by reversed-phase high-performance liquid chromatography. Charybdotoxin is shown to be a highly basic protein with a mass of 10 kDa. Under the standard assay conditions, the purified toxin inhibits the Ca/sup 2 +/-activated K/sup +/ channelmore » with an apparent dissociation constant of 3.5 nM. The protein is unusually stable, with inhibitory potency being insensitive to boiling or exposure to organic solvents. The toxin's activity is sensitive to chymotrypsin treatment and to acylation of lysine groups. The protein may be radioiodinated without loss of activity.« less
Pharr, J R; Coughenour, C A; Bungum, T J
2018-03-01
Obesity and physical inactivity are associated with increased rates of chronic diseases and conditions. However, the 'fit but fat' theory posits that cardiopulmonary fitness (or physical activity) can mitigate risks to health associated with obesity. The purpose of this study was to compare chronic diseases and conditions of highly active/obese women with inactive/normal weight women. This was a cross-sectional study of the 2015 Behavioral Risk Factor Surveillance System data. Weighted descriptive statistics were performed to describe the demographic characteristics of the two groups. We calculated odds ratios and adjusted odds ratios for chronic diseases and conditions comparing highly active/obese women with inactive/normal weight women. Highly active/obese women were more likely to report risk factors (hypertension, high cholesterol, and diabetes) for coronary heart disease (CHD) and cardiovascular disease (CVD) than inactive/normal weight women; however, they did not have increased rates of CVD, CHD, or heart attack and had decreased risk for stroke. Highly active/obese women had increased risk for asthma, arthritis, and depression, but not for cancer, kidney disease, or chronic obstructive pulmonary disease. Highly active/obese women appear to be staving off the actual development of CHD and CVD; however, further research is needed to understand the long-term health benefits of physical activity among obese women. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Hepatitis C virus core protein potentiates proangiogenic activity of hepatocellular carcinoma cells.
Shao, Yu-Yun; Hsieh, Min-Shu; Wang, Han-Yu; Li, Yong-Shi; Lin, Hang; Hsu, Hung-Wei; Huang, Chung-Yi; Hsu, Chih-Hung; Cheng, Ann-Lii
2017-10-17
Increased angiogenic activity has been demonstrated in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC), but the mechanism was unclear. To study the role of HCV core protein, we used tube formation and Matrigel plug assays to assess the proangiogenic activity of an HCC cell line, HuH7, and 2 of its stable clones-HuH7-core-high and HuH7-core-low, with high and low HCV core protein expression, respectively. In both assays, HuH7-core-high and HuH7-core-low cells dose-dependently induced stronger angiogenesis than control cells. HuH7 cells with HCV core protein expression showed increased mRNA and protein expression of vascular endothelial growth factor (VEGF). VEGF inhibition by bevacizumab reduced the proangiogenic activity of HuH7-core-high cells. The promotor region of VEGF contains the binding site of activator protein-1 (AP-1). Compared with controls, HuH7-core-high cells had an increased AP-1 activity and nuclear localization of phospho-c-jun. AP-1 inhibition using either RNA knockdown or AP-1 inhibitors reduced the VEGF mRNA expression and the proangiogenic activity of HuH7-core-high cells. Among 131 tissue samples from HCC patients, HCV-related HCC revealed stronger VEGF expression than did hepatitis B virus-related HCC. In conclusion, increased VEGF expression through AP-1 activation is a crucial mechanism underlying the proangiogenic activity of the HCV core protein in HCC cells.
Hepatitis C virus core protein potentiates proangiogenic activity of hepatocellular carcinoma cells
Shao, Yu-Yun; Hsieh, Min-Shu; Wang, Han-Yu; Li, Yong-Shi; Lin, Hang; Hsu, Hung-Wei; Huang, Chung-Yi; Hsu, Chih-Hung; Cheng, Ann-Lii
2017-01-01
Increased angiogenic activity has been demonstrated in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC), but the mechanism was unclear. To study the role of HCV core protein, we used tube formation and Matrigel plug assays to assess the proangiogenic activity of an HCC cell line, HuH7, and 2 of its stable clones—HuH7-core-high and HuH7-core-low, with high and low HCV core protein expression, respectively. In both assays, HuH7-core-high and HuH7-core-low cells dose-dependently induced stronger angiogenesis than control cells. HuH7 cells with HCV core protein expression showed increased mRNA and protein expression of vascular endothelial growth factor (VEGF). VEGF inhibition by bevacizumab reduced the proangiogenic activity of HuH7-core-high cells. The promotor region of VEGF contains the binding site of activator protein-1 (AP-1). Compared with controls, HuH7-core-high cells had an increased AP-1 activity and nuclear localization of phospho-c-jun. AP-1 inhibition using either RNA knockdown or AP-1 inhibitors reduced the VEGF mRNA expression and the proangiogenic activity of HuH7-core-high cells. Among 131 tissue samples from HCC patients, HCV-related HCC revealed stronger VEGF expression than did hepatitis B virus-related HCC. In conclusion, increased VEGF expression through AP-1 activation is a crucial mechanism underlying the proangiogenic activity of the HCV core protein in HCC cells. PMID:29156827
Is park visitation associated with leisure-time and transportation physical activity?
Veitch, Jenny; Ball, Kylie; Crawford, David; Abbott, Gavin; Salmon, Jo
2013-11-01
The aim of this study was to examine whether frequency of park visitation was associated with time spent in various domains of physical activity among adults living in a disadvantaged neighbourhood of Victoria, Australia. In 2009, participants (n=319) self-reported park visitation and physical activity including: walking and cycling for transport, leisure-time walking, leisure-time moderate- to vigorous-intensity physical activity, and total physical activity. The mean number of park visits per week was 3.3 (SD=3.8). Park visitation was associated with greater odds of engaging in high (as compared to low) amounts of transportation physical activity, leisure-time walking, leisure-time moderate- to vigorous-intensity physical activity (MVPA) and total physical activity. Each additional park visit per week was associated with 23% greater odds of being in the high category for transportation physical activity, 26% greater odds of engaging in high amounts of leisure-time walking, 11% greater odds of engaging in MVPA, and 40% greater odds of high total physical activity. Acknowledging the cross-sectional study design, the findings suggest that park visitation may be an important predictor and/or destination for transportation and leisure-time walking and physical activity. Findings highlight the potentially important role of parks for physical activity. © 2013.
NASA Astrophysics Data System (ADS)
Andas, Jeyashelly; Midon, Muhammad Dzulfiqar
2017-08-01
Highly porous activated carbon was successfully fabricated from the stalk of Nymphaea odorata via single step chemical activation. ZnCl2 was used as the chemical activating agent in the activation process. The raw material was preliminary characterized using Fourier Transform Infrared (FTIR), ultimate analysis (CHNS/O Analyzer) and Scanning Electron Microscope (SEM). The percentage yield, iodine number (IN) and the textural properties of the activated carbon were optimized under the influence of several synthesizing parameters such as impregnation ratio, activation temperature and activation time using ZnCl2. High IN (750.11 mg/g - 967.16 mg/g) was obtained from Sodium thiosulphate volumetric method and represents the porosity of the synthesized materials. Reduction in several functional groups was observed in the FTIR spectrum of the synthesized activated carbon. SEM analysis of the activated carbon verified the formation of highly porous surface compared to the raw Nymphaea odorata. This study provides a facile synthesis of activated carbon from waste natural resources at benign condition.
Outdoor Activity and High Altitude Exposure During Pregnancy: A Survey of 459 Pregnancies.
Keyes, Linda E; Hackett, Peter H; Luks, Andrew M
2016-06-01
To evaluate whether women engage in outdoor activities and high altitude travel during pregnancy; the health care advice received regarding high altitude during pregnancy; and the association between high altitude exposure and self-reported pregnancy complications. An online survey of women with at least 1 pregnancy distributed on websites and e-mail lists targeting mothers and/or mountain activities. Outcome measures were outdoor activities during pregnancy, high altitude (>2440 m) exposure during pregnancy, and pregnancy and perinatal complications. Hiking, running, and swimming were the most common activities performed during pregnancy. Women traveled to high altitude in over half of the pregnancies (244/459), and most did not receive counseling regarding altitude (355, 77%), although a small proportion (14, 3%) were told not to go above 2440 m. Rates of miscarriage and most other complications were similar between pregnancies with and without travel above 2440 m. Pregnancies with high altitude exposure were more likely to have preterm labor (odds ratio [OR] 2.3; 95% CI 0.97-5.4; P = .05). Babies born to women who went to high altitude during pregnancy were more likely to need oxygen at birth (OR 2.34; 95% CI 1.04-5.26; P < .05) but had similar rates of neonatal intensive care unit admission (P = not significant). Our results suggest pregnant women who are active in outdoor sports and travel to high altitude have a low rate of complications. Given the limitations of our data, further research is necessary on the risks associated with high altitude travel and physical activity and how these apply to the general population. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Ultrahigh-sensitive sensing platform based on p-type dumbbell-like Co3O4 network
NASA Astrophysics Data System (ADS)
Zhou, Tingting; Zhang, Tong; Zhang, Rui; Lou, Zheng; Deng, Jianan; Wang, Lili
2017-12-01
Development of high performance room temperature sensors remains a grand challenge for high demand of practical application. Metal oxide semiconductors (MOSs) have many advantages over others due to their easy functionalization, high surface area, and low cost. However, they typically need a high work temperature during sensing process. Here, p-type sensing layer is reported, consisting of pore-rich dumbbell-like Co3O4 particles (DP-Co3O4) with intrinsic high catalytic activity. The gas sensor (GS) based DP-Co3O4 catalyst exhibits ultrahigh NH3 sensing activity along with excellent stability over other structure based NH3 GSs in room temperature work environment. In addition, the unique structure of DP-Co3O4 with pore-rich and high catalytic activity endows fast gas diffusion rate and high sensitivity at room temperature. Taken together, the findings in this work highlight the merit of integrating highly active materials in p-type materials, offering a framework to develop high-sensitivity room temperature sensing platforms.
Fox, Claudia K; Barr-Anderson, Daheia; Neumark-Sztainer, Dianne; Wall, Melanie
2010-01-01
Previous studies have found that higher physical activity levels are associated with greater academic achievement among students. However, it remains unclear whether associations are due to the physical activity itself or sports team participation, which may involve requirements for maintaining certain grades, for example. The purpose of this study is to examine the associations between sports team participation, physical activity, and academic outcomes in middle and high school students. Data were drawn from Project EAT (Eating Among Teens), a survey of middle and high school students (n = 4746). Students self-reported their weekly hours of physical activity, sports team participation, and academic letter grades. Two statistical models were considered: first, 2 separate regression analyses with grade point average (GPA) as the outcome and either sports team participation or physical activity as the predictor; second, a single regression with GPA as the outcome and both sports team participation and physical activity as the simultaneous predictors. For high school girls, both physical activity and sports team participation were each independently associated with a higher GPA. For high school boys, only sports team participation was independently associated with a higher GPA. For middle school students, the positive association between physical activity and GPA could not be separated from the relationship between sports team participation and a higher GPA. Regardless of whether academic success was related to the physical activity itself or to participation on sports teams, findings indicated positive associations between physical activity involvement and academic achievement among students.
[Physical activity, dietary habits and plasma lipoproteins in young men and women].
Malara, Marzena; Lutosławska, Grazyna
2010-01-01
There are studies suggesting that in young women strenuous physical activity and inadequate daily energy intake cause unfavorable changes in lipoprotein profile. However until know data concerning this issue are contradictory, possibly due to small number of participants. This study aimed at evaluation of lipoprotein profile in young men and women with different weekly physical activity together with their dietary habits. A total of 202 subjects volunteered to participate of the study--54 female and 56 male students of physical education and 46 female and 49 male students representing other specialization. Daily energy and macronutrient intakes were assessed using FOOD 2 computer program. Plasma TG, TC and HDL-C were assayed colorimetically using Randox commercial kits (Great Britain). It has been demonstrated that high physical activity adversely affects lipoprotein profile in young women characterized by higher TC and LDL-C in comparison with women with low physical activity and with men with high physical activity. The effect of high physical activity on plasma lipoproteins is equivocal. Active men are characterized by higher HDL, but also by higher frequency of unfavorable plasma TC and similar frequency of unfavorable plasma LDL-C C as compared with their less active counterparts. The mean daily energy intake in highly active men and women covered 82% and 72.2% recommended intake, respectively. It seems feasible that in both sexes high physical activity and inadequate energy intake brings about unfavorable changes in plasma lipoproteins.
pulmonary parameters, BALF biomarkers, body composition, motor activity data collected from rats exposed to ozone after high fructose or high fat diets.This dataset is associated with the following publication:Gordon , C., P. Phillips , A. Johnstone , T. Beasley , A. Ledbetter , M. Schladweiler , S. Snow, and U. Kodavanti. Effect of High Fructose and High Fat Diets on Pulmonary Sensitivity, Motor Activity, and Body Composition of Brown Norway Rats Exposed to Ozone. INHALATION TOXICOLOGY. Taylor & Francis, Inc., Philadelphia, PA, USA, 28(5): 203-15, (2016).
The Costs and Risks of Social Activism: A Study of Sanctuary Movement Activism.
ERIC Educational Resources Information Center
Wiltfang, Gregory L.; McAdam, Doug
1991-01-01
Among 141 activists with varying levels of participation in the sanctuary movement, biographical availability factors--younger age and greater discretionary time--best predict high-cost activism (more hours devoted to the movement), whereas ideological socialization factors best predict high-risk activism (direct contact with refugees). Contains…
Reap around the State: "Best of Reap" Activities.
ERIC Educational Resources Information Center
Indiana State Dept. of Education, Indianapolis. Learning Resources Unit.
This booklet presents selected activities from elementary, middle, junior high, and senior high schools In Indiana, intended to encourage students to read. It offers ideas for 11 community activities (including guest readers, nursing home reading, and a young author celebration), 14 continuous activities (such as the great book graffiti wall and…
Garten, Rebecca; Blanton, Lenee; Elal, Anwar Isa Abd; Alabi, Noreen; Barnes, John; Biggerstaff, Matthew; Brammer, Lynnette; Budd, Alicia P; Burns, Erin; Cummings, Charisse N; Davis, Todd; Garg, Shikha; Gubareva, Larisa; Jang, Yunho; Kniss, Krista; Kramer, Natalie; Lindstrom, Stephen; Mustaquim, Desiree; O'Halloran, Alissa; Sessions, Wendy; Taylor, Calli; Xu, Xiyan; Dugan, Vivien G; Fry, Alicia M; Wentworth, David E; Katz, Jacqueline; Jernigan, Daniel
2018-06-08
The United States 2017-18 influenza season (October 1, 2017-May 19, 2018) was a high severity season with high levels of outpatient clinic and emergency department visits for influenza-like illness (ILI), high influenza-related hospitalization rates, and elevated and geographically widespread influenza activity across the country for an extended period. Nationally, ILI activity began increasing in November, reaching an extended period of high activity during January-February, and remaining elevated through March. Influenza A(H3N2) viruses predominated through February and were predominant overall for the season; influenza B viruses predominated from March onward. This report summarizes U.S. influenza activity* during October 1, 2017-May 19, 2018. † .
The effect of high pressure on the intracellular trehalose synthase activity of Thermus aquaticus.
Dong, Yongsheng; Ma, Lei; Duan, Yuanliang
2016-01-01
To understand the effect of high pressure on the intracellular trehalose synthase activity, Thermus aquaticus (T. aquaticus) in the logarithmic growth phase was treated with high-pressure air, and its intracellular trehalose synthase (TSase) activity was determined. Our results indicated that pressure is a factor strongly affecting the cell growth. High pressure significantly attenuated the growth rate of T. aquaticus and shortened the duration of stationary phase. However, after 2 h of culture under 1.0 MPa pressure, the activity of intracellular TSase in T. aquaticus reached its maximum value, indicating that pressure can significantly increase the activity of intracellular TSase in T. aquaticus. Thus the present study provides an important guide for the enzymatic production of trehalose.
Recent Developments in High Voltage Research in the United Kingdom
NASA Astrophysics Data System (ADS)
Haddad, A. Manu
This paper gives an overview of research activities in the area of high voltage engineering in UK universities. It summarises the main activities of all active high voltage research groups. Furthermore, current research drivers and funding sources for research in the area are described, and the main initiatives to safeguard the health of the discipline are presented.
The physical activity climate in Minnesota middle and high schools.
Samuelson, Anne; Lytle, Leslie; Pasch, Keryn; Farbakhsh, Kian; Moe, Stacey; Sirard, John Ronald
2010-11-01
This article describes policies, practices, and facilities that form the physical activity climate in Minneapolis/St. Paul, Minnesota metro area middle and high schools and examines how the physical activity climate varies by school characteristics, including public/private, school location and grade level. Surveys examining school physical activity practices, policies and environment were administered to principals and physical education department heads from 115 middle and high schools participating in the Transdisciplinary Research on Energetics and Cancer-Identifying Determinants of Eating and Activity (TREC-IDEA) study. While some supportive practices were highly prevalent in the schools studied (such as prohibiting substitution of other classes for physical education); other practices were less common (such as providing opportunity for intramural (noncompetitive) sports). Public schools vs. private schools and schools with a larger school enrollment were more likely to have a school climate supportive of physical activity. Although schools reported elements of positive physical activity climates, discrepancies exist by school characteristics. Of note, public schools were more than twice as likely as private schools to have supportive physical activity environments. Establishing more consistent physical activity expectations and funding at the state and national level is necessary to increase regular school physical activity.
Chiu, Chen-Yuan; Feng, Shih-An; Liu, Shing-Hwa; Chiang, Meng-Tsan
2017-07-24
The present study investigated and compared the regulatory effects on the lipid-related metabolism and intestinal disaccharidase/fecal bacterial enzyme activities between low molecular weight chitosan and chitosan oligosaccharide in high-fat-diet-fed rats. Diet supplementation of low molecular weight chitosan showed greater efficiency than chitosan oligosaccharide in suppressing the increased weights in body and in liver and adipose tissues of high-fat-diet-fed rats. Supplementation of low molecular weight chitosan also showed a greater improvement than chitosan oligosaccharide in imbalance of plasma, hepatic, and fecal lipid profiles, and intestinal disaccharidase activities in high-fat-diet-fed rats. Moreover, both low molecular weight chitosan and chitosan oligosaccharide significantly decreased the fecal microflora mucinase and β-glucuronidase activities in high-fat-diet-fed rats. These results suggest that low molecular weight chitosan exerts a greater positive improvement than chitosan oligosaccharide in lipid metabolism and intestinal disaccharidase activity in high-fat-diet-induced obese rats.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dollan, Ralph; Haeusler, Uwe; Czarwinski, Renate
2013-07-01
Effective regulatory control is essential to ensure the safe and secure use of radioactive material and the appropriate management of radioactive waste. To ensure a sustainable control of high radioactive sources, the European Commission published the Council Directive 2003/122/EURATOM on the control of high-activity sealed radioactive sources and orphan sources, which had to be transferred into national legislation by all member states of the European Union. Major requirement of the Directive is a system to ensure traceability of high-activity sealed sources from 'cradle to grave' as well as the provision to take back disused sources by the supplier or manufacturer.more » With the Act on high-activity sealed radioactive sources Germany implemented the requirements of the Directive 2003/122/EURATOM and established a national registry of high-activity sealed sources in 2006. Currently, about 27.000 high-activity sealed sources are recorded in this national registry. (authors)« less
Tribology of alternative bearings.
Fisher, John; Jin, Zhongmin; Tipper, Joanne; Stone, Martin; Ingham, Eileen
2006-12-01
The tribological performance and biological activity of the wear debris produced has been compared for highly cross-linked polyethylene, ceramic-on-ceramic, metal-on-metal, and modified metal bearings in a series of in vitro studies from a single laboratory. The functional lifetime demand of young and active patients is 10-fold greater than the estimated functional lifetime of traditional polyethylene. There is considerable interest in using larger diameter heads in these high demand patients. Highly cross-linked polyethylene show a four-fold reduction in functional biological activity. Ceramic-on-ceramic bearings have the lowest wear rates and least reactive wear debris. The functional biological activity is 20-fold lower than with highly cross-linked polyethylene. Hence, ceramic-on-ceramic bearings address the tribological lifetime demand of highly active patients. Metal-on-metal bearings have substantially lower wear rates than highly cross-linked polyethylene and wear decreases with head diameter. Bedding in wear is also lower with reduced radial clearance. Differential hardness ceramic-on-metal bearings and the application of ceramic-like coatings reduce metal wear and ion levels.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Yue; Li, Hongbo; Hao, Jun
Podocytes are highly specialized and terminally differentiated glomerular cells that play a vital role in the development and progression of diabetic nephropathy (DN). Cyclin-dependent kinase 5 (Cdk5), who is an atypical but essential member of the Cdk family of proline-directed serine/threonine kinases, has been shown as a key regulator of podocyte differentiation, proliferation and morphology. Our previous studies demonstrated that the expression of Cdk5 was significantly increased in podocytes of diabetic rats, and was closely related with podocyte injury of DN. However, the mechanisms of how expression and activity of Cdk5 are regulated under the high glucose environment have notmore » yet been fully elucidated. In this study, we showed that high glucose up-regulated the expression of Cdk5 and its co-activator p35 with a concomitant increase in Cdk5 kinase activity in conditionally immortalized mouse podocytes in vitro. When exposed to 30 mM glucose, transforming growth factor-β1 (TGF-β1) was activated. Most importantly, we found that SB431542, the Tgfbr1 inhibitor, significantly decreased the expression of Cdk5 and p35 and Cdk5 kinase activity in high glucose-treated podocytes. Moreover, high glucose increased the expression of early growth response-1 (Egr-1) via TGF-β1-ERK1/2 pathway in podocytes and inhibition of Egr-1 by siRNA decreased p35 expression and Cdk5 kinase activity. Furthermore, inhibition of Cdk5 kinase activity effectively alleviated podocyte apoptosis induced by high glucose or TGF-β1. Thus, the TGF-β1-ERK1/2-Egr-1 signaling pathway may regulate the p35 expression and Cdk5 kinase activity in high glucose-treated podocytes, which contributes to podocyte injury of DN. - Highlights: • HG up-regulated the expression of Cdk5 and p35, and Cdk5 activity in podocytes. • HG activated TGF-β1 pathway and SB431542 inhibited Cdk5 expression and activity. • HG increased the expression of Egr-1 via TGF-β1-ERK1/2 pathway. • Inhibition of Egr-1 decreased p35 expression in HG-cultured podocytes. • Inhibition of Cdk5 activity alleviated podocyte apoptosis induced by HG or TGF-β1.« less
Guo, Chunxian; Zheng, Yao; Ran, Jingrun; Xie, Fangxi; Jaroniec, Mietek; Qiao, Shi-Zhang
2017-07-10
Engineering high-energy interfacial structures for high-performance electrocatalysis is achieved by chemical coupling of active CoO nanoclusters and high-index facet Mn 3 O 4 nano-octahedrons (hi-Mn 3 O 4 ). A thorough characterization, including synchrotron-based near edge X-ray absorption fine structure, reveals that strong interactions between both components promote the formation of high-energy interfacial Mn-O-Co species and high oxidation state CoO, from which electrons are drawn by Mn III -O present in hi-Mn 3 O 4 . The CoO/hi-Mn 3 O 4 demonstrates an excellent catalytic performance over the conventional metal oxide-based electrocatalysts, which is reflected by 1.2 times higher oxygen evolution reaction (OER) activity than that of Ru/C and a comparable oxygen reduction reaction (ORR) activity to that of Pt/C as well as a better stability than that of Ru/C (95 % vs. 81 % retained OER activity) and Pt/C (92 % vs. 78 % retained ORR activity after 10 h running) in alkaline electrolyte. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Lo, Hui-Wen; Cao, Xinyu; Zhu, Hu; Ali-Osman, Francis
2009-01-01
Purpose The goals of this study are to elucidate the relationship of the oncogenic transcription factor signal transducer and activator of transcription 3(STAT3) with glioma aggressiveness and to understand the role of high STAT3 activity in the resistance of malignant gliomas and medulloblastomas to chemotherapy. Experimental Design Immunohistochemical staining and biochemical methods were used to examine the extent of STAT3 activation and EGFR expression in primary specimens and cell lines, respectively. Cellular response to drug treatments was determined using cell cytotoxicity and clonogenic growth assays. Results We found STAT3 to be constitutively activated in 60% of primary high-grade/malignant gliomas and the extent of activation correlated positively with glioma grade. High levels of activated/phosphorylated STAT3 were also present in cultured human malignant glioma and medulloblastoma cells. Three STAT3-activating kinases, Janus-activated kinase 2 (JAK2), EGFR, and EGFRvIII, contributed to STAT3 activation. An inhibitor toJAK2/STAT3, JSI-124, significantly reduced expression of STAT3 target genes, suppressed cancer cell growth, and induced apoptosis. Furthermore, we found that STAT3 constitutive activation coexisted with EGFR expression in 27.2% of primary high-grade/malignant gliomas and such coexpression correlated positively with glioma grade. Combination of an anti-EGFR agent Iressa and a JAK2/STAT3 inhibitor synergistically suppressed STAT3 activation and potently killed glioblastoma cell lines that expressed EGFR or EGFRvIII. JSI-124 also sensitized malignant glioma and medulloblastoma cells to temozolomide, 1,3-bis(2-chloroethyl)-1-nitrosourea, and cisplatin in which a synergism existed between JSI-124 and cisplatin. Conclusion STAT3 constitutive activation, alone and in concurrence with EGFR expression, plays an important role in high-grade/malignant gliomas and targeting STAT3/JAK2 sensitizes these tumors to anti-EGFR and alkylating agents. PMID:18829483
Simmonds, B A J; Hannam, K J; Fox, K R; Tobias, J H
2016-03-01
This qualitative study explored the acceptability of high-impact physical activity for increasing bone strength in later life. Thematic analysis established the barriers and facilitators to this physical activity. They prioritised joint over skeletal health, of which they had little concept. Interventions need to clearly communicate the rationale and benefits. The aim of this study was to explore the acceptability of doing high-impact physical activity in later life. This qualitative study was embedded within a large-scale observational study and was designed to address specific objectives and feed into a subsequent intervention. Five focus groups with physically active men and women (over 50 years) were used to develop an interview topic guide to explore the acceptability of high-impact physical activity in older men and women (over 65 years) in South West England. A total of 28 semi-structured interviews with 31 participants were then conducted and transcripts analysed thematically. Three main barriers emerged: conceptualising bone, damage to joints and falling/safety concerns. Two main facilitators were also identified: the need to understand clear tangible benefits and incorporation of activity into everyday habits. Older adults were interested how high-impact physical activity would help to maintain their mobility, independence or social relationships. Some participants wanted tangible feedback from accelerometers, health care professionals and/or bone scans in order to develop a more intimate knowledge of their bone health. Interventions incorporating high-impact physical activity for older adults need to communicate how this activity can impact more broadly on health and lives; that physical activity will be safe, beneficial and not damaging to their joints will need to be clearly conveyed. Ways in which high-impact physical activity can be habitualised into everyday activities, be fun and interactive may help facilitate longer term adoption.
Marcos-Zambrano, Laura Judith; Escribano, Pilar; Bouza, Emilio; Guinea, Jesús
2016-02-01
Micafungin is more active against biofilms with high metabolic activity; however, it is unknown whether this observation applies to caspofungin and anidulafungin and whether it is also dependent on the biomass production. We compare the antifungal activity of anidulafungin, caspofungin, and micafungin against preformed Candida albicans biofilms with different degrees of metabolic activity and biomass production from 301 isolates causing fungemia in patients admitted to Gregorio Marañon Hospital (January 2007 to September 2014). Biofilms were classified as having low, moderate, or high metabolic activity according XTT reduction assay or having low, moderate, or high biomass according to crystal violet assay. Echinocandin MICs for planktonic and sessile cells were measured using the EUCAST E.Def 7.2 procedure and XTT reduction assay, respectively. Micafungin showed the highest activity against biofilms classified according to the metabolic activity and biomass production (P < .001). The activity of caspofungin and anidulafungin was not dependent on the metabolic activity of the biofilm or the biomass production. These observations were confirmed by scanning electron microscopy. None of the echinocandins produced major changes in the structure of biofilms with low metabolic activity and biomass production when compared with the untreated biofilms. However, biofilm with high metabolic activity or high biomass production was considerably more susceptible to micafungin; this effect was not shown by caspofungin or anidulafungin. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Leisure-time physical activity and psychological well-being in university students.
Molina-García, J; Castillo, I; Queralt, A
2011-10-01
An analysis of psychological well-being (self-esteem and subjective vitality) of 639 Spanish university students was performed, while accounting for the amount of leisure-time physical activity. The Spanish versions of the Rosenberg Self-Esteem Scale and Subjective Vitality Scale were employed. Participants were divided into four groups (Low, Moderate, High, and Very high) depending on estimation of energy expenditure in leisure-time physical activity. Men and women having higher physical activity rated higher mean subjective vitality; however, differences in self-esteem were observed only in men, specifically between Very high and the other physical activity groups.
Jiang, Chunfang; Zheng, Hai; Liu, Sunan; Fang, Kaifeng
2008-02-01
The relationship between intracellular trypsinogen activation and NF-kappa B activation in rat pancreatic acinar cells induced by M3 cholinergic receptor agonist (carbachol) hyperstimulation was studied. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc) and NF-kappa B inhibitor (PDTC) in vitro. Intracellular trypsin activity was measured by using a fluorogenic substrate. The activity of NF-kappa B was monitored by using electrophoretic mobility shift assay. The results showed that after pretreatment with 2 mmol/L pefabloc, the activities of trypsin and NF-kappa B in pancreatic acinar cells treated with high concentrations of carbachol (10(-3) mol/L) in vitro was significantly decreased as compared with control group (P<0.01). The addition of 10(-2) mol/L PDTC resulted in a significant decrease of NF-kappa B activities in pancreatic acinar cells after treated with high concentrations of carbachol (10(-3) mol/L) in vitro, but the intracellular trypsinogen activity was not obviously inhibited (P>0.05). It was concluded that intracellular trypsinogen activation is likely involved in the regulation of high concentrations of carbachol-induced NF-kappa B activation in pancreatic acinar cells in vitro. NF-kappa B activation is likely not necessary for high concentrations of carbachol-induced trypsinogen activation in pancreatic acinar cells in vitro.
Older Adults' Opinions on Fall Prevention in Relation to Physical Activity Level.
Tuvemo Johnson, Susanna; Martin, Cathrin; Anens, Elisabeth; Johansson, Ann-Christin; Hellström, Karin
2018-01-01
The purpose of this study was to explore and describe older adults' opinions regarding actions to prevent falls and to analyze differences in the opinions of highly versus less physically active older adults. An open-ended question was answered by 262 individuals aged 75 to 98 years living in the community. The answers were analyzed using qualitative content analysis, and differences in the categories were compared between highly and less physically active persons. Physical activity was measured according to a five-level scale. The content analysis resulted in eight categories: assistive devices, avoiding hazards, behavioral adaptive strategies, being physically active, healthy lifestyle, indoor modifications, outdoor modifications, and seeking assistance. Behavioral adaptive strategies were mentioned to a greater extent by highly active people, and indoor modifications were more often mentioned by less active older adults. Support for active self-directed behavioral strategies might be important for fall prevention among less physically active older adults.
Association between active commuting and elevated blood pressure in adolescents
Santana, Fábio da Silva; Palmeira, Aline Cabral; dos Santos, Marcos André Moura; Farah, Breno Quintella; de Souza, Bruna Cadengue Coêlho; Ritti-Dias, Raphael Mendes
2017-01-01
ABSTRACT Objective To analyze the association between active commuting and blood pressure in adolescents. Methods This is a cross-sectional study with high school students from public education network in the state of Pernambuco, Brazil. Data from 6039 students (14 to 19 years) were collected using a questionnaire. “Physically inactive” were considered those who reported not to walk or ride a bicycle to and from school on any day of the past week, and/or those who, regardless of the weekly frequency of practice this type of activity, reported the duration of commuting to school was less than 20 minutes (round trip). The high blood pressure was obtained by Omron HEM 742 equipment. Adolescents with high blood pressure were defined as those with higher blood pressure or equal to the 95th percentile for age, sex and height. Regression logistic analyses were used to assess the association between active commuting and high blood pressure, considering adjustments for the following confounders: sex, age, overweight, total physical activity, socioeconomic level, place of residence. Results The prevalence of high blood pressure was 7.3%, and 79.3% were considered insufficiently active in commuting. There was an association between high blood pressure and active commuting only among those living in rural areas (OR = 6.498; 95% CI = 1.513-27.900), and the same was not observed among those living in urban areas (OR = 1.113; 95% CI = 0.812-1.526). Conclusion Active commuting can be considered a protective factor for high blood pressure in adolescents living in rural areas. PMID:29364363
Kunin, Margarita; Dmitrieva, Natalia I; Gallazzini, Morgan; Shen, Rong-Fong; Wang, Guanghui; Burg, Maurice B; Ferraris, Joan D
2010-08-11
Hypertonicity, such as induced by high NaCl, increases the activity of the transcription factor TonEBP/OREBP whose target genes increase osmoprotective organic osmolytes and heat shock proteins. We used mass spectrometry to analyze proteins that coimmunoprecipitate with TonEBP/OREBP in order to identify ones that might contribute to its high NaCl-induced activation. We identified 20 unique peptides from Mediator of DNA Damage Checkpoint 1 (MDC1) with high probability. The identification was confirmed by Western analysis. We used small interfering RNA knockdown of MDC1 to characterize its osmotic function. Knocking down MDC1 reduces high NaCl-induced increases in TonEBP/OREBP transcriptional and transactivating activity, but has no significant effect on its nuclear localization. We confirm six previously known phosphorylation sites in MDC1, but do not find evidence that high NaCl increases phosphorylation of MDC1. It is suggestive that MDC1 acts as a DNA damage response protein since hypertonicity reversibly increases DNA breaks, and other DNA damage response proteins, like ATM, also associate with TonEBP/OREBP and contribute to its activation by hypertonicity. MDC1 associates with TonEBP/OREBP and contributes to high NaCl-induced increase of that factor's transcriptional activity.
Barengo, Noël C; Hu, Gang; Lakka, Timo A; Pekkarinen, Heikki; Nissinen, Aulikki; Tuomilehto, Jaakko
2004-12-01
To investigate separately for men and women whether moderate or high leisure time physical activity, occupational physical activity, and commuting activity are associated with a reduced cardiovascular disease (CVD) and all-cause mortality, independent of CVD risk factors and other forms of physical activity. Prospective follow-up of 15,853 men and 16,824 women aged 30-59 years living in eastern and south-western Finland (median follow-up time 20 years). CVD and all-cause mortality were lower (9-21%) in men and women (2-17%) who were moderately or highly physically active during leisure time. Moderate and high levels of occupational physical activity decreased CVD and all-cause mortality by 21-27% in both sexes. Women spending daily 15 min or more in walking or cycling to and from work had a reduced CVD and all-cause mortality before adjustment for occupational and leisure time physical activity. Commuting activity was not associated with CVD or all-cause mortality in men. Moderate and high levels of leisure time and occupational physical activity are associated with a reduced CVD and all-cause mortality among both sexes. Promoting already moderate levels of leisure time and occupational physical activity are essential to prevent premature CVD and all-cause mortality.
Fundamental movement skills and motivational factors influencing engagement in physical activity.
Kalaja, Sami; Jaakkola, Timo; Liukkonen, Jarmo; Watt, Anthony
2010-08-01
To assess whether subgroups based on children's fundamental movement skills, perceived competence, and self-determined motivation toward physical education vary with current self-reported physical activity, a sample of 316 Finnish Grade 7 students completed fundamental movement skills measures and self-report questionnaires assessing perceived competence, self-determined motivation toward physical education, and current physical activity. Cluster analysis indicated a three-cluster structure: "Low motivation/low skills profile," "High skills/low motivation profile," and "High skills/high motivation profile." Analysis of variance indicated that students in the third cluster engaged in significantly more physical activity than students of clusters one and two. These results provide support for previous claims regarding the importance of the relationship of fundamental movement skills with continuing engagement in physical activity. High fundamental movement skills, however, may represent only one element in maintaining adolescents' engagement in physical activity.
NASA Astrophysics Data System (ADS)
Acar Sesen, Burcin; Tarhan, Leman
2013-02-01
This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental ( N = 30) and control groups ( N = 32). The experimental group was taught using inquiry-based laboratory activities developed by the researchers and the control group was instructed using traditional laboratory activities. The results of the study indicated that instruction based on inquiry-based laboratory activities caused a significantly better acquisition of scientific concepts related to electrochemistry, and produced significantly higher positive attitudes towards chemistry and laboratory. In the light of the findings, it is suggested that inquiry-based laboratory activities should be developed and applied to promote students' understanding in chemistry subjects and to improve their positive attitudes.
Cytoprotective effect of seaweeds with high antioxidant activity from the Peniche coast (Portugal).
Pinteus, Susete; Silva, Joana; Alves, Celso; Horta, André; Fino, Nádia; Rodrigues, Ana Inês; Mendes, Susana; Pedrosa, Rui
2017-03-01
Screening of antioxidant potential of dichloromethane and methanolic extracts of twenty-seven seaweeds from the Peniche coast was performed by: total phenolic contents (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC). Seaweeds revealing the highest antioxidant activity were screened for cytoprotective potential in MCF-7 cells, including the mitochondrial membrane potential analysis and the caspase-9 activity. High correlation was found between TPC of seaweed extracts and their scavenging capacity on DPPH and peroxyl radicals. The highest antioxidant activity was displayed by the methanolic fraction of brown seaweeds belonging to Fucales, however Ulva compressa presented the highest cytoprotective effect by blunting the apoptosis process. These results suggest that high antioxidant activity may not be directly related with high cytoprotective potential. Thus, seaweeds reveal to be a promising source of compounds with potential against oxidative stress. Copyright © 2016 Elsevier Ltd. All rights reserved.
Relationship between diet and physical activity level in adolescents from post-grammar schools.
Dmitruk, Agnieszka; Kunicka, Izabela; Popławska, Helena; Hołub, Wojciech
2016-01-01
Appropriate diet and physical activity are vital determinants of psychophysical development in children and adolescents. The aim of the study was to analyse an association between dietary habits and physical activity levels of adolescents from post-grammar schools. The study included 110 girls and 65 boys between 16 and 19 years of age from two post-grammar schools in Biała Podlaska in Poland. They were subjected to a diagnostic survey providing information on their diet (number of meals a day, their regularity, frequency of bread, dairy, meat, fish, sweet, fruit, vegetable and fast food consumption, preferred ways of food processing). Physical activity levels were determined with the International Physical Activity Questionnaire--Short Form (IPAQ-SF). Based on these data, the respondents were stratified to high, moderate and low physical activity groups. Due to small number of participants presenting with low physical activity levels, we did not include this group in further analyses. The significance of differences in the dietary habits of adolescents presenting with high and moderate physical activity levels was verified with the χ2 test. Most girls and boys presented with high levels of physical activity. However, we did not find an evident relationship between dietary habits and physical activity levels. Girls from high and moderate physical activity groups differed solely in terms of the number of daily meals, frequency of meat and sweet consumption, and significant intergroup differences observed among boys pertained to the frequencies of whole-wheat bread, meat and fast food consumption. The abovementioned food products were consumed more often by girls and boys presenting with high physical activity levels. The dietary mistakes observed in physically active adolescents from post-secondary schools justify intensification of their dietary education programs.
ERIC Educational Resources Information Center
Abakay, Ugur
2013-01-01
This study was carried out to detect the differences in submissive behaviors and communication skills of high school students in terms of sports activities and relationship between communication skills and properties of submissive behavior of high school students who are actively involved in sports activities. In this respect at the study, 728…
ERIC Educational Resources Information Center
Forneris, Tanya; Camiré, Martin; Williamson, Robert
2015-01-01
In order to prepare students for adulthood and responsible citizenship, most high schools offer extracurricular activities designed to facilitate the learning of a wide range of competencies. The purpose of this study was to examine how participation in a single or a combination of extracurricular school activities for high school students may…
Preparation of Labeled Aflatoxins with High Specific Activities
Hsieh, D. P. H.; Mateles, R. I.
1971-01-01
Resting cells of Aspergillus parasiticus ATCC 15517 were used to prepare highly labeled aflatoxins from labeled acetate. High synthetic activity in growing cells was evidenced only during 40 to 70 hr of incubation. Glucose was required for high incorporation efficiency, whereas the concentration of the labeled acetate determined the specific activity of the product. When labeled acetate was continuously added to maintain a concentration near but not exceeding 10 mm, in a culture containing 30 g of glucose per liter, 2% of its labels could be recovered in the purified aflatoxins which have a specific activity more than three times that of the labeled acetate. PMID:4329435
Trends in emerging and high risk activities
Robert C. White; Richard Schreyer; Kent Downing
1980-01-01
Newly emerging and high risk activities have increased markedly in the last generation, yet little is known about trends in participation. Factors such as technological innovation and creative experimentation with traditional activities appear to play a major role in the development of new activities. Christy's criteria for mass demand in recreation are used to...
Apaoblaza, A; Galaz, A; Strobel, P; Ramírez-Reveco, A; Jeréz-Timaure, N; Gallo, C
2015-03-01
Muscle glycogen concentration (MGC) and lactate (LA), activity of glycogen debranching enzyme (GDE), glycogen phosphorylase (GP) and adenosine monophosphate kinase (AMPK) were determined at 0.5h (T0) and 24h (T24) post-mortem in Longissimus dorsi samples from 38 steers that produced high pH (>5.9) and normal pH (<5.8) carcasses at 24h postmortem. MGC, LA and glycolytic potential were higher (P<0.05) in normal pH carcasses. GDE activity was similar (P>0.05) in both pH categories. GP activity increased between T0 and T24 only in normal pH carcasses. AMPK activity was four times higher in normal pH v/s high pH carcasses, without changing its activity over time. Results reinforce the idea that differences in postmortem glycogenolytic/glycolytic flow in L. dorsi of steers showing normal v/s high muscle pH at 24h, could be explained not only by the higher initial MGC in normal pH carcasses, but also by a high and sustained activity of AMPK and an increased GP activity at 24h postmortem. Copyright © 2014 Elsevier Ltd. All rights reserved.
Wrosch, Carsten; Sabiston, Catherine M
2013-03-01
This longitudinal study examined whether goal adjustment capacities (i.e., goal disengagement and goal reengagement) would predict breast cancer survivors' emotional well-being and physical health by facilitating high levels of physical activity and low levels of sedentary activity. Self-reports of goal adjustment capacities were measured among 176 female breast cancer survivors at baseline. Self-reports of physical activity, sedentary activity, daily affect, and daily physical health symptoms (e.g., nausea or pain) were measured at baseline and 3-month follow-up. Goal reengagement predicted high levels of positive affect and low levels of physical symptoms at baseline and increases in positive affect over 3 months. The combination of high goal disengagement and high goal reengagement was associated with particularly large 3-month increases in positive affect. The effects of goal reengagement on baseline affect and physical health were mediated by high baseline levels of physical activity, and the interaction effect on 3-month changes in positive affect was mediated by low baseline levels of sedentary activity. Goal adjustment capacities can exert beneficial effects on breast cancer survivors' well-being and physical health by facilitating adaptive levels of physical and sedentary activity. Integrating goal adjustment processes into clinical practice may be warranted. Copyright © 2012 John Wiley & Sons, Ltd.
Peng, Yong; Shao, Hui; Ke, Yan; Zhang, Ping; Han, Gencheng; Kaplan, Henry J.; Sun, Deming
2008-01-01
Purpose Results in previous reports have demonstrated that immunization of the EAU-prone B6 mouse activates both CD4 and CD8 IRBP-specific T cells. The purpose of this study was to investigate structural and functional differences between CD4 and CD8 autoreactive T cells activated by the uveitogenic peptide. Methods Purified CD4 and CD8 isolated from B6 mice immunized with an uveitogenic peptide, interphotoreceptor retin-oid-binding protein (IRBP)1-20, were stimulated in vitro with various doses of immunizing peptide. The activated T cells were determined for cytokine production, expression of Foxp3, and suppressor activity. Results CD4 autoreactive T cells underwent full activation when stimulated with high or medium concentrations of immunizing peptide, whereas a high dose of antigenic peptide resulted in only modest activation of CD8 autoreactive T cells. When stimulated by a low dose (<0.1 μg/mL) of antigen or by of a high dose of antigen and a small amount of TGF-β1, the minimally activated CD8 T cells expressed a high level of Foxp3 and gained suppressor function. Conclusions Minimally activated CD8 autoreactive T cells can be functionally suppressive and may neutralize the tissue-damaging effect of the CD4 autoreactive T cells. PMID:17460277
NASA Astrophysics Data System (ADS)
Javed, Muhammad Sufyan; Dai, Shuge; Wang, Mingjun; Xi, Yi; Lang, Qiang; Guo, Donglin; Hu, Chenguo
2015-08-01
The exploration of high Faradic redox active materials with the advantages of low cost and low toxicity has been attracting great attention for producing high energy storage supercapacitors. Here, the high Faradic redox active material of Cu7S4-NWs coated on a carbon fiber fabric (CFF) is directly used as a binder-free electrode for a high performance flexible solid state supercapacitor. The Cu7S4-NW-CFF supercapacitor exhibits excellent electrochemical performance such as a high specific capacitance of 400 F g-1 at the scan rate of 10 mV s-1 and a high energy density of 35 Wh kg-1 at a power density of 200 W kg-1, with the advantages of a light weight, high flexibility and long term cycling stability by retaining 95% after 5000 charge-discharge cycles at a constant current of 10 mA. The high Faradic redox activity and high conductance behavior of the Cu7S4-NWs result in a high pseudocapacitive performance with a relatively high specific energy and specific power. Such a new type of pseudocapacitive material of Cu7S4-NWs with its low cost is very promising for actual application in supercapacitors.The exploration of high Faradic redox active materials with the advantages of low cost and low toxicity has been attracting great attention for producing high energy storage supercapacitors. Here, the high Faradic redox active material of Cu7S4-NWs coated on a carbon fiber fabric (CFF) is directly used as a binder-free electrode for a high performance flexible solid state supercapacitor. The Cu7S4-NW-CFF supercapacitor exhibits excellent electrochemical performance such as a high specific capacitance of 400 F g-1 at the scan rate of 10 mV s-1 and a high energy density of 35 Wh kg-1 at a power density of 200 W kg-1, with the advantages of a light weight, high flexibility and long term cycling stability by retaining 95% after 5000 charge-discharge cycles at a constant current of 10 mA. The high Faradic redox activity and high conductance behavior of the Cu7S4-NWs result in a high pseudocapacitive performance with a relatively high specific energy and specific power. Such a new type of pseudocapacitive material of Cu7S4-NWs with its low cost is very promising for actual application in supercapacitors. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03363b
Physical activity, diet, and risk of Alzheimer disease.
Scarmeas, Nikolaos; Luchsinger, Jose A; Schupf, Nicole; Brickman, Adam M; Cosentino, Stephanie; Tang, Ming X; Stern, Yaakov
2009-08-12
Both higher adherence to a Mediterranean-type diet and more physical activity have been independently associated with lower Alzheimer disease (AD) risk but their combined association has not been investigated. To investigate the combined association of diet and physical activity with AD risk. Prospective cohort study of 2 cohorts comprising 1880 community-dwelling elders without dementia living in New York, New York, with both diet and physical activity information available. Standardized neurological and neuropsychological measures were administered approximately every 1.5 years from 1992 through 2006. Adherence to a Mediterranean-type diet (scale of 0-9; trichotomized into low, middle, or high; and dichotomized into low or high) and physical activity (sum of weekly participation in various physical activities, weighted by the type of physical activity [light, moderate, vigorous]; trichotomized into no physical activity, some, or much; and dichotomized into low or high), separately and combined, were the main predictors in Cox models. Models were adjusted for cohort, age, sex, ethnicity, education, apolipoprotein E genotype, caloric intake, body mass index, smoking status, depression, leisure activities, a comorbidity index, and baseline Clinical Dementia Rating score. Time to incident AD. A total of 282 incident AD cases occurred during a mean (SD) of 5.4 (3.3) years of follow-up. When considered simultaneously, both Mediterranean-type diet adherence (compared with low diet score, hazard ratio [HR] for middle diet score was 0.98 [95% confidence interval {CI}, 0.72-1.33]; the HR for high diet score was 0.60 [95% CI, 0.42-0.87]; P = .008 for trend) and physical activity (compared with no physical activity, the HR for some physical activity was 0.75 [95% CI, 0.54-1.04]; the HR for much physical activity was 0.67 [95% CI, 0.47-0.95]; P = .03 for trend) were associated with lower AD risk. Compared with individuals neither adhering to the diet nor participating in physical activity (low diet score and no physical activity; absolute AD risk of 19%), those both adhering to the diet and participating in physical activity (high diet score and high physical activity) had a lower risk of AD (absolute risk, 12%; HR, 0.65 [95% CI, 0.44-0.96]; P = .03 for trend). In this study, both higher Mediterranean-type diet adherence and higher physical activity were independently associated with reduced risk for AD.
NASA Astrophysics Data System (ADS)
Kuwata, M.; Shao, W.; Lebouteiller, R.; Martin, S. T.
2012-12-01
The governing highly soluble, slightly soluble, or insoluble activation regime of organic compounds as cloud condensation nuclei (CCN) was examined as a function of oxygen-to-carbon elemental ratio (O : C). New data were collected for adipic, pimelic, suberic, azelaic and pinonic acids. Secondary organic materials (SOMs) produced by α-pinene ozonolysis and isoprene photo-oxidation were also included in the analysis. The saturation concentrations C of the organic compounds in aqueous solutions served as the key parameter for delineating regimes of CCN activation, and the values of C were tightly correlated to the O : C ratios. The highly soluble, slightly soluble, and insoluble regimes of CCN activation were found to correspond to ranges of [O : C] > 0.6, 0.2 < [O : C] < 0.6, and [O : C] < 0.2, respectively. These classifications were evaluated against CCN activation data of isoprene-derived SOM (O : C = 0.69-0.72) and α-pinene-derived SOM (O : C = 0.38-0.48). Isoprene-derived SOM had highly soluble activation behavior, consistent with its high O : C ratio. For α-pinene-derived SOM, although CCN activation can be modeled as a highly soluble mechanism, this behavior was not predicted by the O : C ratio, for which a slightly soluble mechanism was anticipated. Complexity in chemical composition, resulting in continuous water uptake and the absence of a deliquescence transition that can thermodynamically limit CCN activation, might explain the differences of α-pinene-derived SOM compared to the behavior of pure organic compounds. The present results suggest that atmospheric particles dominated by hydrocarbon-like organic components do not activate (i.e. insoluble regime) whereas those dominated by oxygenated organic components activate (i.e. highly soluble regime).
NASA Astrophysics Data System (ADS)
Kuwata, M.; Shao, W.; Lebouteiller, R.; Martin, S. T.
2013-05-01
The governing highly soluble, slightly soluble, or insoluble activation regime of organic compounds as cloud condensation nuclei (CCN) was examined as a function of oxygen-to-carbon elemental ratio (O : C). New data were collected for adipic, pimelic, suberic, azelaic, and pinonic acids. Secondary organic materials (SOMs) produced by α-pinene ozonolysis and isoprene photo-oxidation were also included in the analysis. The saturation concentrations C of the organic compounds in aqueous solutions served as the key parameter for delineating regimes of CCN activation, and the values of C were tightly correlated to the O : C ratios. The highly soluble, slightly soluble, and insoluble regimes of CCN activation were found to correspond to ranges of [O : C] > 0.6, 0.2 < [O : C] < 0.6, and [O : C] < 0.2, respectively. These classifications were evaluated against CCN activation data of isoprene-derived SOM (O : C = 0.69-0.72) and α-pinene-derived SOM (O : C = 0.38-0.48). Isoprene-derived SOM had highly soluble activation behavior, consistent with its high O : C ratio. For α-pinene-derived SOM, although CCN activation can be modeled as a highly soluble mechanism, this behavior was not predicted by the O : C ratio, for which a slightly soluble mechanism was anticipated. Complexity in chemical composition, resulting in continuous water uptake and the absence of a deliquescence transition that can thermodynamically limit CCN activation, might explain the difference in the behavior of α-pinene-derived SOM compared to that of pure organic compounds. The present results suggest that atmospheric particles dominated by hydrocarbon-like organic components do not activate (i.e., insoluble regime) whereas those dominated by oxygenated organic components activate (i.e., highly soluble regime) for typical atmospheric cloud life cycles.
Super-SERS-active and highly effective antimicrobial Ag nanodendrites
NASA Astrophysics Data System (ADS)
Li, H. B.; Liu, P.; Liang, Y.; Xiao, J.; Yang, G. W.
2012-07-01
We have developed simple and green electrochemistry to synthesize Ag nanostructures with high purity, good crystallinity and smooth surface for applications as super-SERS (surface-enhanced Raman scattering), SERS-active substrates and with highly effective antimicrobial activities. This synthesis takes place in a clean and slow reaction environment without any chemical additives, which ensures an ultrahigh active surface of the as-synthesized Ag nanostructures owing to their purity, good crystallinity and smooth morphology. Using this method, we synthesized nearly perfect Ag nanodendrites (NDs), which exhibit super-SERS sensitivity when they are used to detect the SERS spectra of rhodamine 6G at concentrations as low as 5 × 10-16 M, and have an ultrahigh electromagnetic (EM) enhancement factor of the order of 1013, breaking through the theoretical limit of EM enhancement. Meanwhile, the as-synthesized Ag NDs possess highly effective antimicrobial activities for Escherichia coli, Candida albicans and Staphylococcus aureus, which are over 10 times that of silver nanoparticles. Additionally, the basic physics and chemistry involved in the fabrication of Ag nanostructures are pursued. These investigations show that silver nanostructures with highly active surfaces can make the most of Ag nanostructures functioning as super-SERS-active substrates and multiple antibiotics.
Effect of Increasing the Choice of Active Options on Children’s Physical Activity
Feda, Denise M.; Lambiase, Maya J.; McCarthy, Thomas F.; Barkley, Jacob E.; Roemmich, James. N.
2012-01-01
Objectives To determine whether increasing the choice of physical activity options increases the duration and intensity of children’s physically active play. Design This cross-sectional laboratory study included gender (male, female) and choice group [single toy (no choice), three toys (low choice), five toys (high choice)] as between participant factors. Methods Boys and girls (n = 36, 8–12 y) were stratified, randomly assigned to a choice group that always provided access to each participant’s most liked active toy(s), and allowed 60 min of free time. The same sedentary alternatives were freely available to all participants. Physical activity outcomes were measured by accelerometry, heart rate, and direct observation. Results The number of active toys the children played with increased (p < 0.001) across each choice group. Minutes spent in MPA were greater in the low choice (p < 0.05) and high choice (p < 0.02) groups than the no choice group. Active play time was greater (p < 0.01) in the low choice (79%) and high choice (95%) groups compared to the no choice group. Girls in the low and high choice groups had greater (p < 0.05) percent heart rate reserve when compared to girls in the no choice group. There was no difference in the boys’ percent heart rate reserve between the no choice, low choice and high choice groups. Conclusions Increasing the choice of active toys increases both the duration and intensity of physically active play, especially in girls. PMID:22342111
Potiaumpai, Melanie; Martins, Maria Carolina Massoni; Wong, Claudia; Desai, Trusha; Rodriguez, Roberto; Mooney, Kiersten; Signorile, Joseph F
2017-02-01
To compare the difference in muscle activation between high-speed yoga and standard-speed yoga and to compare muscle activation of the transitions between poses and the held phases of a yoga pose. Randomized sequence crossover trial SETTING: A laboratory of neuromuscular research and active aging Interventions: Eight minutes of continuous Sun Salutation B was performed, at a high speed versus a standard-speed, separately. Electromyography was used to quantify normalized muscle activation patterns of eight upper and lower body muscles (pectoralis major, medial deltoids, lateral head of the triceps, middle fibers of the trapezius, vastus medialis, medial gastrocnemius, thoracic extensor spinae, and external obliques) during the high-speed and standard-speed yoga protocols. Difference in normalized muscle activation between high-speed yoga and standard-speed yoga. Normalized muscle activity signals were significantly higher in all eight muscles during the transition phases of poses compared to the held phases (p<0.01). There was no significant interaction between speed×phase; however, greater normalized muscle activity was seen for highspeed yoga across the entire session. Our results show that transitions from one held phase of a pose to another produces higher normalized muscle activity than the held phases of the poses and that overall activity is greater during highspeed yoga than standard-speed yoga. Therefore, the transition speed and associated number of poses should be considered when targeting specific improvements in performance. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wei, Haoran; Deng, Shubo; Hu, Bingyin; Chen, Zhenhe; Wang, Bin; Huang, Jun; Yu, Gang
2012-12-01
Cost-effective biomass-derived activated carbons with a high CO(2) adsorption capacity are attractive for carbon capture. Bamboo was found to be a suitable precursor for activated carbon preparation through KOH activation. The bamboo size in the range of 10-200 mesh had little effect on CO(2) adsorption, whereas the KOH/C mass ratio and activation temperature had a significant impact on CO(2) adsorption. The bamboo-derived activated carbon had a high adsorption capacity and excellent selectivity for CO(2) , and also the adsorption process was highly reversible. The adsorbed amount of CO(2) on the granular activated carbon was up to 7.0 mmol g(-1) at 273 K and 1 bar, which was higher than almost all carbon materials. The pore characteristics of activated carbons responsible for high CO(2) adsorption were fully investigated. Based on the analysis of narrow micropore size distribution of several activated carbons prepared under different conditions, a more accurate micropore range contributing to CO(2) adsorption was proposed. The volume of micropores in the range of 0.33-0.82 nm had a good linear relationship with CO(2) adsorption at 273 K and 1 bar, and the narrow micropores of about 0.55 nm produced the major contribution, which could be used to evaluate CO(2) adsorption on activated carbons. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Topanurak, Supachai; Ferraris, Joan D; Li, Jinxi; Izumi, Yuichiro; Williams, Chester K; Gucek, Marjan; Wang, Guanghui; Zhou, Xiaoming; Burg, Maurice B
2013-04-30
Glycerophosphocholine (GPC) is high in cells of the renal inner medulla where high interstitial NaCl and urea power concentration of the urine. GPC protects inner medullary cells against the perturbing effects of high NaCl and urea by stabilizing intracellular macromolecules. Degradation of GPC is catalyzed by the glycerophosphocholine phosphodiesterase activity of glycerophosphodiester phosphodiesterase domain containing 5 (GDPD5). We previously found that inhibitory posttranslational modification (PTM) of GDPD5 contributes to high NaCl- and urea-induced increase of GPC. The purpose of the present studies was to identify the PTM(s). We find at least three such PTMs in HEK293 cells: (i) Formation of a disulfide bond between C25 and C571. High NaCl and high urea increase reactive oxygen species (ROS). The ROS increase disulfide bonding between GDPD5-C25 and -C571, which inhibits GDPD5 activity, as supported by the findings that the antioxidant N-acetylcysteine prevents high NaCl- and urea-induced inhibition of GDPD5; GDPD5-C25S/C571S mutation or over expression of peroxiredoxin increases GDPD5 activity; H2O2 inhibits activity of wild type GDPD5, but not of GDPD5-C25S/C571S; and peroxiredoxin is relatively low in the renal inner medulla where GPC is high. (ii) Dephosphorylation of GDPD5-T587. GDPD5 threonine 587 is constitutively phosphorylated. High NaCl and high urea dephosphorylate GDPD5-T587. Mutation of GDPD5-T587 to alanine, which cannot be phosphorylated, decreases GPC-PDE activity of GDPD5. (iii) Alteration at an unknown site mediated by CDK1. Inhibition of CDK1 protein kinase reduces GDE-PDE activity of GDPD5 without altering phosphorylation at T587, and CDK1/5 inhibitor reduces activity of GDPD5- C25S/C571S-T587A.
Topanurak, Supachai; Ferraris, Joan D.; Li, Jinxi; Izumi, Yuichiro; Williams, Chester K.; Gucek, Marjan; Wang, Guanghui; Zhou, Xiaoming; Burg, Maurice B.
2013-01-01
Glycerophosphocholine (GPC) is high in cells of the renal inner medulla where high interstitial NaCl and urea power concentration of the urine. GPC protects inner medullary cells against the perturbing effects of high NaCl and urea by stabilizing intracellular macromolecules. Degradation of GPC is catalyzed by the glycerophosphocholine phosphodiesterase activity of glycerophosphodiester phosphodiesterase domain containing 5 (GDPD5). We previously found that inhibitory posttranslational modification (PTM) of GDPD5 contributes to high NaCl- and urea-induced increase of GPC. The purpose of the present studies was to identify the PTM(s). We find at least three such PTMs in HEK293 cells: (i) Formation of a disulfide bond between C25 and C571. High NaCl and high urea increase reactive oxygen species (ROS). The ROS increase disulfide bonding between GDPD5-C25 and -C571, which inhibits GDPD5 activity, as supported by the findings that the antioxidant N-acetylcysteine prevents high NaCl- and urea-induced inhibition of GDPD5; GDPD5-C25S/C571S mutation or over expression of peroxiredoxin increases GDPD5 activity; H2O2 inhibits activity of wild type GDPD5, but not of GDPD5-C25S/C571S; and peroxiredoxin is relatively low in the renal inner medulla where GPC is high. (ii) Dephosphorylation of GDPD5-T587. GDPD5 threonine 587 is constitutively phosphorylated. High NaCl and high urea dephosphorylate GDPD5-T587. Mutation of GDPD5-T587 to alanine, which cannot be phosphorylated, decreases GPC-PDE activity of GDPD5. (iii) Alteration at an unknown site mediated by CDK1. Inhibition of CDK1 protein kinase reduces GDE-PDE activity of GDPD5 without altering phosphorylation at T587, and CDK1/5 inhibitor reduces activity of GDPD5- C25S/C571S-T587A. PMID:23589856
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-20
...-frequency or high frequency active sonar (MFAS/HFAS) or to underwater detonations at levels that NMFS... exposing them to sound from mid-frequency or high frequency active sonar (MFAS/HFAS) or underwater...
Tachibanaki, Shuji; Arinobu, Daisuke; Shimauchi-Matsukawa, Yoshie; Tsushima, Sawae; Kawamura, Satoru
2005-06-28
Cone photoreceptors show briefer photoresponses than rod photoreceptors. Our previous study showed that visual pigment phosphorylation, a quenching mechanism of light-activated visual pigment, is much more rapid in cones than in rods. Here, we measured the early time course of this rapid phosphorylation with good time resolution and directly compared it with the photoresponse time course in cones. At the time of photoresponse recovery, almost two phosphates were incorporated into a bleached cone pigment molecule, which indicated that the visual pigment phosphorylation coincides with the photoresponse recovery. The rapid phosphorylation in cones is attributed to very high activity of visual pigment kinase [G protein-coupled receptor kinase (GRK) 7] in cones. Because of this high activity, cone pigment is readily phosphorylated at very high bleach levels, which probably explains why cone photoresponses recover quickly even after a very bright light and do not saturate under intense background light. The high GRK7 activity is brought about by high content of a highly potent enzyme. The expression level of GRK7 was 10 times higher than that of rod kinase (GRK1), and the specific activity of a single GRK7 molecule was approximately 10 times higher than that of GRK1. The specific activity of GRK7 is the highest among the GRKs so far known. Our result seems to explain the response characteristics of cone photoreceptors in many aspects, including the nonsaturation of the cone responses during daylight vision.
Pope, Lizzy; Garnett, Bernice; Dibble, Marguerite
2018-04-01
To encourage high school students to meet physical activity goals using a newly developed game, and to document the feasibility, benefits, and challenges of using an electronic gaming application to promote physical activity in high school students. Working with youth and game designers an electronic game, Camp Conquer, was developed to motivate high school students to meet physical activity goals. One-hundred-five high school students were recruited to participate in a 12-week pilot test of the game and randomly assigned to a Game Condition or Control Condition. Students in both conditions received a FitBit to track their activity, and participants in the Game Condition received access to Camp Conquer. Number of steps and active minutes each day were tracked for all participants. FitBit use, game logins, and qualitative feedback from researchers, school personnel, and participants were used to determine intervention engagement. The majority of study participants did not consistently wear their FitBit or engage with the gaming intervention. Numerous design challenges and barriers to successful implementation such as the randomized design, absence of a true school-based champion, ease of use, and game glitches were identified. Developing games is an exciting technique for motivating the completion of a variety of health behaviors. Although the present intervention was not successful in increasing physical activity in high school students, important lessons were learned regarding how to best structure a gaming intervention for the high school population.
An alkaline active xylanase: insights into mechanisms of high pH catalytic adaptation.
Mamo, Gashaw; Thunnissen, Marjolein; Hatti-Kaul, Rajni; Mattiasson, Bo
2009-09-01
The alkaliphilic bacterium, Bacillus halodurans S7, produces an alkaline active xylanase (EC 3.2.1.8), which differs from many other xylanases in being operationally stable under alkaline conditions as well as at elevated temperature. Compared to non-alkaline active xylanases, this enzyme has a high percent composition of acidic amino acids which results in high ratio of negatively to positively charged residues. A positive correlation was observed between the charge ratio and the pH optima of xylanases. The recombinant xylanase was crystallized using a hanging drop diffusion method. The crystals belong to the space group P2(1)2(1)2(1) and the structure was determined at a resolution of 2.1 A. The enzyme has the common eight-fold TIM-barrel structure of family 10 xylanases; however, unlike non-alkaline active xylanases, it has a highly negatively charged surface and a deeper active site cleft. Mutational analysis of non-conserved amino acids which are close to the acid/base residue has shown that Val169, Ile170 and Asp171 are important to hydrolyze xylan at high pH. Unlike the wild type xylanase which has optimum pH at 9-9.5, the triple mutant xylanase (V169A, I170F and D171N), which was constructed using sequence information of alkaline sensitive xylanses was optimally active around pH 7. Compared to non-alkaline active xylanases, the alkaline active xylanases have highly acidic surfaces and fewer solvent exposed alkali labile residues. Based on these results obtained from sequence, structural and mutational analysis, the possible mechanisms of high pH stability and catalysis are discussed. This will provide useful information to understand the mechanism of high pH adaptation and engineering of enzymes that can be operationally stable at high pH.
Kobza, Richard; Duru, Firat; Erne, Paul
2008-07-01
Physicians who are caring for patients with implantable cardioverter-defibrillators (ICDs) are regularly confronted with questions concerning daily activities. This study evaluates the habits of ICD patients with respect to sports activities, stays at high-altitude, and driving patterns. A survey was performed in 387 patients with ICDs who were followed at two hospitals in Switzerland. The special-designed questionnaire addressed lifestyle practices concerning sports activity, high-altitude visits, and driving motor vehicles. Fifty-nine percent of ICD patients participated in some kind of sports activity; an ICD shock was experienced in 14% of these patients. Fifty-six percent of the patients reported a stay at high altitudes at least 2,000 m above the sea level; 11% of them stayed regularly above 2,500 m; 4% of these patients experienced an ICD shock during high altitude stay. Seventy-nine percent of the patients drove a motor vehicle; 2% of them experienced an ICD shock during driving, but none of them reported loss of consciousness or a traffic accident. It is accepted that ICD patients disqualify for competitive sports. However, the patients may be encouraged to continue leisure-time physical activities at low-to-moderate intensity. Staying at high altitudes and driving motor vehicles are very rarely associated with ICD shocks. Therefore, these activities that are likely to contribute to a better quality of life should not be discouraged in most ICD recipients in the absence of other medical reasons.
Ufarté, Lisa; Bozonnet, Sophie; Laville, Elisabeth; Cecchini, Davide A; Pizzut-Serin, Sandra; Jacquiod, Samuel; Demanèche, Sandrine; Simonet, Pascal; Franqueville, Laure; Veronese, Gabrielle Potocki
2016-01-01
Activity-based metagenomics is one of the most efficient approaches to boost the discovery of novel biocatalysts from the huge reservoir of uncultivated bacteria. In this chapter, we describe a highly generic procedure of metagenomic library construction and high-throughput screening for carbohydrate-active enzymes. Applicable to any bacterial ecosystem, it enables the swift identification of functional enzymes that are highly efficient, alone or acting in synergy, to break down polysaccharides and oligosaccharides.
Active tuning of high-Q dielectric metasurfaces
Parry, Matthew; Komar, Andrei; Hopkins, Ben; ...
2017-08-02
Here, we demonstrate the active tuning of all-dielectric metasurfaces exhibiting high-quality factor (high-Q) resonances. The active control is provided by embedding the asymmetric silicon meta-atoms with liquid crystals, which allows the relative index of refraction to be controlled through heating. It is found that high quality factor resonances (Q = 270 ± 30) can be tuned over more than three resonance widths. Our results demonstrate the feasibility of using all-dielectric metasurfaces to construct tunable narrow-band filters.
Cheng, Hong Sheng; Yaw, Hui Ping; Ton, So Ha; Choy, Siew Mei; Kong, Joana Magdelene Xiao Fang; Abdul Kadir, Khalid
2016-09-01
To investigate the effects of glycyrrhizic acid supplementation on glucose and lipid metabolism in rodents consuming a high-fat, high-sucrose diet. Twenty-four male, 8-week old Sprague Dawley rats with an initial weight of 160 to 200 g were randomised into three groups (n = 6 for each group): groups A (standard rat chow), B (high-fat, high-sucrose diet), and C (high-fat, high-sucrose diet + 100 mg/kg/d of glycyrrhizic acid via oral administration). The rats were treated accordingly for 4 wk. Glycaemic parameters, lipid profile, stress hormones, and adiponectin levels were measured after the treatment. Relative gene expressions of peroxisome proliferator-activated receptor α and γ, lipoprotein lipase as well as gluconeogenic enzymatic activities in different tissues were also determined. Consumption of high-fat, high-sucrose diet triggered hyperglycaemia, insulin resistance, and dyslipidemia, which were effectively attenuated by supplementation with glycyrrhizic acid. Glycyrrhizic acid supplementation also effectively reduced circulating adrenaline, alleviated gluconeogenic enzymes overactivity, and promoted the upregulation of lipoprotein lipase expression in the cardiomyocytes and skeletal muscles. A high calorie diet also triggered hypoadiponectinaemia and suppression of peroxisome proliferator-activated receptor γ expression, which did not improve with glycyrrhizic acid treatment. Supplementation with glycyrrhizic acid could alleviate high calorie diet-induced glucose and lipid metabolic dysregulations by reducing circulatory stress hormones, normalizing gluconeogenic enzyme activities, and elevating muscular lipid uptake. The beneficial effects of these bioactivities outweighed the adverse effects caused by diet-induced repression of peroxisome proliferator-activated receptor γ expression, resulting in the maintenance of lipid and glucose homeostasis. Copyright © 2016 Elsevier Inc. All rights reserved.
Active Gaming Among High School Students--United States, 2010.
Song, MinKyoung; Carroll, Dianna D; Lee, Sarah M; Fulton, Janet E
2015-08-01
Our study is the first to describe the prevalence and correlates (demographics, body mass index [BMI], sedentary behaviors, and physical activity) of high school youth who report active videogame playing (active gaming) in a U.S. representative sample. The National Youth Physical Activity and Nutrition Study of 2010 provided data for this study. Active gaming was assessed as the number of days in the 7 days prior to the survey that students in grades 9-12 (14-18 years of age) reported participating in active videogames (e.g., "Wii™ Fit" [Nintendo, Kyoto, Japan], "Dance Dance Revolution" [Konami, Osaka, Japan]). Students reporting ≥1 days were classified as active gamers. Logistic regression was used to examine the association among active gaming and demographic characteristics, BMI, sedentary behaviors, and physical activity. Among 9125 U.S. high school students in grades 9-12 surveyed, 39.9 percent (95 percent confidence interval=37.9 percent, 42.0 percent) reported active gaming. Adjusting for covariates, the following characteristics were positively associated (P<0.05) with active gaming: being in 9th and 10th grades compared with being in 12th grade; being of black, non-Hispanic race/ethnicity; being overweight or obese; watching DVDs >0 hours/day; watching TV >0 hours/day; and meeting guidelines for aerobic and muscle-strengthening physical activity. Four out of 10 U.S. high school students report participating in active gaming. Active gamers tend to spend more time watching DVDs or TV, meet guidelines for physical activity, and/or be overweight or obese compared with nonactive gamers. These findings may serve to provide a baseline to track active gaming in U.S. youth and inform interventions that target sedentary behaviors and/or physical activity.
Bade, Michael; Struessel, Tamara; Paxton, Roger; Winters, Joshua; Baym, Carol; Stevens-Lapsley, Jennifer
2018-01-01
To determine the relation between performance on a clinical quadriceps activation battery with (1) activation measured by doublet interpolation and (2) recovery of quadriceps strength and functional performance after total knee arthroplasty (TKA). Planned secondary analysis of a randomized controlled trial. University research laboratory. Patients (N=162; mean age, 63±7y; 89 women) undergoing TKA. Patients were classified as high (quadriceps activation battery ≥4/6) or low (quadriceps activation battery ≤3/6) based on performance on the quadriceps activation battery measured 4 days after TKA. Differences between groups in activation and recovery at 1, 2, 3, 6, and 12 months after TKA were compared using a repeated-measures maximum likelihood model. The low quadriceps activation battery group demonstrated poorer quadriceps activation via doublet interpolation (P=.01), greater quadriceps strength loss (P=.01), and greater functional performance decline (all P<.001) at 1 month after TKA compared with the high quadriceps activation battery group. Differences between low and high quadriceps activation battery groups on all measures did not persist at 3 and 12 months (all P>.05). Poor performance on the quadriceps activation battery early after TKA is related to poor quadriceps activation and poor recovery in the early postoperative period. Patients in the low quadriceps activation battery group took 3 months to recover to the same level as the high quadriceps activation battery group. The quadriceps activation battery may be useful in identifying individuals who need specific interventions to target activation deficits or different care pathways in the early postoperative period to speed recovery after TKA. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
2017-01-01
General locomotor activity (GLA) in poultry has attracted attention, as it negatively influences production costs (energy expenditure and feed consumption) and welfare parameters (bone strength, litter quality, feather pecking and cannibalism). Laying hen lines diverging in the average level of spontaneous locomotor activity in the home pen were developed by genetic selection using the founder New Hampshire line. Activity was recorded using RFID technology at around five weeks of age during four to five days in the home pen. After initial phenotyping, the least active birds were selected for the low activity line and the most active for the high activity line, with no gene transfer between lines. In each of six generations, approximately ten sires were mated to twenty dams producing 158 to 334 offspring per line per generation. The response to selection was rapid and of a considerable magnitude. In sixth generation, the level of GLA was approximately halved in the low and doubled in the high line compared to the control (7.2, 14.9 and 28.7 recordings/h). Estimated heritability of locomotor activity in the low and high line was 0.38 and 0.33, respectively. Males, in general, were more active than females. High line birds were significantly heavier than low line birds. In fourth, fifth, and sixth generation, low as well as high line birds were lighter than control line birds. This selection experiment demonstrates variation in heritability for GLA and, as a result, genetically diverged lines have been developed. These lines can be used as models for further studies of underlying physiological, neural and molecular genetic mechanisms of spontaneous locomotor activity. PMID:28796792
Kjaer, Joergen B
2017-01-01
General locomotor activity (GLA) in poultry has attracted attention, as it negatively influences production costs (energy expenditure and feed consumption) and welfare parameters (bone strength, litter quality, feather pecking and cannibalism). Laying hen lines diverging in the average level of spontaneous locomotor activity in the home pen were developed by genetic selection using the founder New Hampshire line. Activity was recorded using RFID technology at around five weeks of age during four to five days in the home pen. After initial phenotyping, the least active birds were selected for the low activity line and the most active for the high activity line, with no gene transfer between lines. In each of six generations, approximately ten sires were mated to twenty dams producing 158 to 334 offspring per line per generation. The response to selection was rapid and of a considerable magnitude. In sixth generation, the level of GLA was approximately halved in the low and doubled in the high line compared to the control (7.2, 14.9 and 28.7 recordings/h). Estimated heritability of locomotor activity in the low and high line was 0.38 and 0.33, respectively. Males, in general, were more active than females. High line birds were significantly heavier than low line birds. In fourth, fifth, and sixth generation, low as well as high line birds were lighter than control line birds. This selection experiment demonstrates variation in heritability for GLA and, as a result, genetically diverged lines have been developed. These lines can be used as models for further studies of underlying physiological, neural and molecular genetic mechanisms of spontaneous locomotor activity.
Cyst fluid telomerase activity predicts the histologic grade of cystic neoplasms of the pancreas
Hata, Tatsuo; Molin, Marco Dal; Suenaga, Masaya; Yu, Jun; Pittman, Meredith; Weiss, Matthew; Canto, Marcia I.; Wolfgang, Christopher; Lennon, Anne Marie; Hruban, Ralph H; Goggins, Michael
2016-01-01
Purpose Pancreatic cysts frequently pose clinical dilemmas. On one hand, cysts with high-grade dysplasia offer opportunities for cure, on the other hand, those with low-grade dysplasia are easily over treated. Cyst fluid markers have the potential to improve the evaluation of these cysts. Since telomerase activity is commonly activated in malignant cells, we evaluated the diagnostic performance of cyst fluid telomerase activity measurements for predicting histologic grade. Experimental design Telomerase activity was measured using telomerase repeat amplification with digital-droplet PCR in surgically-aspirated cyst fluid samples from 219 patients who underwent pancreatic resection for a cystic lesion (184, discovery, 35 validation) and 36 patients who underwent endoscopic ultrasound fine needle aspiration. Methodological and clinical factors associated with telomerase activity were examined. Results Telomerase activity was reduced in samples that had undergone prior thawing. Among 119 samples not previously thawed, surgical cyst fluids from cystic neoplasms with high-grade dysplasia +/− associated invasive cancer had higher telomerase activity (median [interquartile range], 1158 [295.9–13033] copies/μL of cyst fluid than those without (19.74 [2.58–233.6] copies/μL) (P < 0.001). Elevated cyst fluid telomerase activity had a diagnostic accuracy for invasive cancer/high-grade dysplasia of 88.1% (discovery), 88.6% (validation), and 88.2% (merged). Among cysts classified preoperatively as having “worrisome features”, cyst fluid telomerase activity had high diagnostic performance (sensitivity 73.7%, specificity 90.6%, accuracy, 86.1%). In multivariate analysis, telomerase activity independently predicted the presence of invasive cancer/high-grade dysplasia. Conclusion Cyst fluid telomerase activity can be a useful predictor of the neoplastic grade of pancreatic cysts. PMID:27230749
Chen, Zigui; Buckley, Niall; Lo, Yungtai; Ratner, Adam J.
2014-01-01
Objective Female genital tract secretions inhibit E. coli ex vivo and the activity may prevent colonization and provide a biomarker of a healthy microbiome. We hypothesized that high E. coli inhibitory activity would be associated with a Lactobacillus crispatus and/or jensenii dominant microbiome and differ from that of women with low inhibitory activity. Study Design Vaginal swab cell pellets from 20 samples previously obtained in a cross-sectional study of near-term pregnant and non-pregnant healthy women were selected based on having high (>90% inhibition) or low (<20% inhibition) anti-E. coli activity. The V6 region of the 16S ribosomal RNA gene was amplified and sequenced using the Illumina HiSeq 2000 platform. Filtered culture supernatants from Lactobacillus crispatus, Lactobacillus iners, and Gardnerella vaginalis were also assayed for E. coli inhibitory activity. Results Sixteen samples (10 with high and 6 with low activity) yielded evaluable microbiome data. There was no difference in the predominant microbiome species in pregnant compared to non-pregnant women (n = 8 each). However, there were significant differences between women with high compared to low E. coli inhibitory activity. High activity was associated with a predominance of L. crispatus (p<0.007) and culture supernatants from L. crispatus exhibited greater E. coli inhibitory activity compared to supernatants obtained from L. iners or G. vaginalis. Notably, the E. coli inhibitory activity varied among different strains of L. crispatus. Conclusion Microbiome communities with abundant L. crispatus likely contribute to the E. coli inhibitory activity of vaginal secretions and efforts to promote this environment may prevent E. coli colonization and related sequelae including preterm birth. PMID:24805362
ERIC Educational Resources Information Center
Bobbett, Gordon C.; And Others
This paper presents a study attempting to identify and evaluate high school activities that impact instrumental student outcome. High school music activities and their impact on student instrumental outcome from a variety of perspectives were examined. There is a subtle difference between musical independence and musical achievement. Musical…
Heat Stable Enzymes from Thermophiles
1998-02-01
final product and is somewhat messy to work with. Therefore, alternatives were tested. However, no combination of corn syrup , alternative sugars and...INTRODUCTION 9 CLONING OF ALKALINE PHOSPHATASE GENE AND PRODUCTION OF HIGH SPECIFIC ACTIVITY ENZYME 9 Cloning into E. coil and expression of high activity...JKR209, into an alternative, better producing organism. CLONING OF ALKALINE PHOSPHATASE GENE AND PRODUCTION OF HIGH SPECIFIC ACTIVITY ENZYME Cloning into
Perez-Leighton, Claudio E.; Boland, Kelsey; Billington, Charles; Kotz, Catherine M.
2012-01-01
Humans and rodents show large variability in their individual sensitivity to diet-induced obesity, which has been associated with differences in intrinsic spontaneous physical activity (SPA). Evidence from genetic and out-bred rat obesity models shows that higher activity of the orexin peptides results in higher intrinsic SPA and protection against diet-induced obesity. Based on this, we hypothesized that naturally occurring variation in SPA and orexin signaling activity is sufficient to drive differences in sensitivity to diet-induced obesity. We analyzed orexin activity and sensitivity to diet-induced obesity in non-manipulated male Sprague Dawley rats selected for high and low intrinsic SPA. Our results defined a new model of differential DIO sensitivity, the high-activity and low activity-rats, and suggest that naturally occurring variations in intrinsic SPA cause differences in energy expenditure that are mediated by orexin signaling and alter DIO sensitivity. PMID:23404834
Cos, P; Hermans, N; De Bruyne, T; Apers, S; Sindambiwe, J B; Vanden Berghe, D; Pieters, L; Vlietinck, A J
2002-02-01
A total of 45 Rwandan plant extracts, belonging to 37 different plant species out of 21 families, were investigated for their antibacterial, antifungal, and antiviral properties. The plants were selected on the base of their ethnomedicinal use against infections and autoimmune diseases. From all the plant extracts tested, only Clematis hirsuta (leaves) showed a pronounced antifungal activity against Candida albicans and the dermatophytes Trichophyton rubrum, Epidermophyton floccosum, and Microsporum canis. Seven plant extracts showed a high antiviral activity against the DNA-virus Herpes simplex type 1, while five and three plant extracts were highly active against the RNA-viruses Coxsackie and Polio, respectively. Only Macaranga kilimandscharica (leaves) showed an interesting anti-measles activity, whereas Eriosema montanum (leaves) and Entada abyssinica (leaves) were highly active against Semliki forest virus. Some plant extracts showed an antibacterial activity against Gram-positive bacteria and Mycobacterium fortuitum, but none of them were active against the Gram-negative bacteria tested.
Influence of High School Physical Education on University Student's Physical Activity
ERIC Educational Resources Information Center
Kimball, Jessica; Jenkins, Jayne; Wallhead, Tristan
2009-01-01
The purpose of this study was to use the Lifelong Physical Activity (LLPA) framework to examine the influence of high school physical education (PE) on university students' level of physical activity (PA). Participants included 365 undergraduate students from the Rocky Mountain West of the USA enrolled in a university physical activity course.…
Eight Stars of Gold--The Story of Alaska's Flag. High School Activities (Grades 9-12).
ERIC Educational Resources Information Center
Alaska State Museum, Juneau.
This activities booklet focuses on the story of Alaska's flag. The booklet is intended for use in teaching high school students. Each activity contains: background information; a summary and time estimate, Alaska state standards, a step-by-step technique for classroom implementation of the activity, assessment tips, materials and resources needed,…
ERIC Educational Resources Information Center
Nahas, Markus V.; Goldfine, Bernie; Collins, Mitchell A.
2003-01-01
Reviews factors that influence high school and college students' physical activity adoption and/or maintenance based on recent behavioral research. Relevant determinants of physical activity include self-efficacy, intentions, perceived barriers, enjoyment, stages of change, and social support. Suggestions for behavior modifications to increase…
ERIC Educational Resources Information Center
Ebie, Brian D.
2005-01-01
The purpose of this study was to discover the self-reported reasons for involvement in after-school, extracurricular music and athletic activities of high school students. One hundred-sixty high school students participating in either extracurricular athletic or musical activities served as subjects. Extracurricular activities were defined as…
Changes in Women's Physical Activity during the Transition to College
ERIC Educational Resources Information Center
Han, Jennifer L.; Dinger, Mary K.; Hull, Holly R.; Randall, Nichole B.; Heesch, Kristiann C.; Fields, David A.
2008-01-01
Background: Few studies have examined physical activity during the transition from high school to college. Purpose: To examine changes in physical activity and physical activity patterns among females during the transition from high school to college. Methods: Sixty-nine females (age 18.2 [plus or minus] 0.4 years; body mass index 21.8 [plus or…
Ding, Liang-Xin; Wang, An-Liang; Ou, Yan-Nan; Li, Qi; Guo, Rui; Zhao, Wen-Xia; Tong, Ye-Xiang; Li, Gao-Ren
2013-01-01
Hierarchical alloy nanosheet dendrites (ANSDs) are highly favorable for superior catalytic performance and efficient utilization of catalyst because of the special characteristics of alloys, nanosheets, and dendritic nanostructures. In this paper, we demonstrate for the first time a facile and efficient electrodeposition approach for the controllable synthesis of Pd-Sn ANSDs with high surface area. These synthesized Pd-Sn ANSDs exhibit high electrocatalytic activity and superior long-term cycle stability toward ethanol oxidation in alkaline media. The enhanced electrocataytic activity of Pd-Sn ANSDs may be attributed to Pd-Sn alloys, nanosheet dendrite induced promotional effect, large number of active sites on dendrite surface, large surface area, and good electrical contact with the base electrode. Because of the simple implement and high flexibility, the proposed approach can be considered as a general and powerful strategy to synthesize the alloy electrocatalysts with high surface areas and open dendritic nanostructures.
Ding, Liang-Xin; Wang, An-Liang; Ou, Yan-Nan; Li, Qi; Guo, Rui; Zhao, Wen-Xia; Tong, Ye-Xiang; Li, Gao-Ren
2013-01-01
Hierarchical alloy nanosheet dendrites (ANSDs) are highly favorable for superior catalytic performance and efficient utilization of catalyst because of the special characteristics of alloys, nanosheets, and dendritic nanostructures. In this paper, we demonstrate for the first time a facile and efficient electrodeposition approach for the controllable synthesis of Pd-Sn ANSDs with high surface area. These synthesized Pd-Sn ANSDs exhibit high electrocatalytic activity and superior long-term cycle stability toward ethanol oxidation in alkaline media. The enhanced electrocataytic activity of Pd-Sn ANSDs may be attributed to Pd-Sn alloys, nanosheet dendrite induced promotional effect, large number of active sites on dendrite surface, large surface area, and good electrical contact with the base electrode. Because of the simple implement and high flexibility, the proposed approach can be considered as a general and powerful strategy to synthesize the alloy electrocatalysts with high surface areas and open dendritic nanostructures. PMID:23383368
Strategic and Operational Plan for Integrating Transcriptomics ...
Plans for incorporating high throughput transcriptomics into the current high throughput screening activities at NCCT; the details are in the attached slide presentation presentation on plans for incorporating high throughput transcriptomics into the current high throughput screening activities at NCCT, given at the OECD meeting on June 23, 2016
Sid, Victoria; Wu, Nan; Sarna, Lindsei K.; Siow, Yaw L.; House, James D.
2015-01-01
AMPK is an endogenous energy sensor that regulates lipid and carbohydrate metabolism. Nonalcoholic fatty liver disease (NAFLD) is regarded as a hepatic manifestation of metabolic syndrome with impaired lipid and glucose metabolism and increased oxidative stress. Our recent study showed that folic acid supplementation attenuated hepatic oxidative stress and lipid accumulation in high-fat diet-fed mice. The aim of the present study was to investigate the effect of folic acid on hepatic AMPK during high-fat diet feeding and the mechanisms involved. Male C57BL/6J mice were fed a control diet (10% kcal fat), a high-fat diet (60% kcal fat), or a high-fat diet supplemented with folic acid (26 mg/kg diet) for 5 wk. Mice fed a high-fat diet exhibited hyperglycemia, hepatic cholesterol accumulation, and reduced hepatic AMPK phosphorylation. Folic acid supplementation restored AMPK phosphorylation (activation) and reduced blood glucose and hepatic cholesterol levels. Activation of AMPK by folic acid was mediated through an elevation of its allosteric activator AMP and activation of its upstream kinase, namely, liver kinase B1 (LKB1) in the liver. Consistent with in vivo findings, 5-methyltetrahydrofolate (bioactive form of folate) restored phosphorylation (activation) of both AMPK and LKB1 in palmitic acid-treated HepG2 cells. Activation of AMPK by folic acid might be responsible for AMPK-dependent phosphorylation of HMG-CoA reductase, leading to reduced hepatic cholesterol synthesis during high-fat diet feeding. These results suggest that folic acid supplementation may improve cholesterol and glucose metabolism by restoration of AMPK activation in the liver. PMID:26400185
Thogersen-Ntoumani, Cecilie; Black, Julie; Lindwall, Magnus; Whittaker, Anna; Balanos, George M
2017-12-01
This study used a person-centred approach to explore typologies of older manual workers based on presenteeism, stress resilience, and physical activity. Older manual workers ( n = 217; 69.1% male; age range 50-77; M age = 57.11 years; SD = 5.62) from a range of UK-based organisations, representing different manual job roles, took part in the study. A cross-sectional survey design was used. Based on the three input variables: presenteeism, stress resilience and physical activity, four distinct profiles were identified on using Latent Profile Analysis. One group ('High sport/exercise and well-functioning'; 5.50%) engaged in high levels of sport/exercise and exhibited low levels of stress resilience and all types of presenteeism. Another profile ('Physically burdened'; 9.70%) reported high levels of work and leisure-time physical activity, low stress resilience, as well as high levels of presenteeism due to physical and time demands. A 'Moderately active and functioning' group (46.50%) exhibited moderate levels on all variables. Finally, the fourth profile ('Moderately active with high presenteeism'; 38.20%) reported engaging in moderate levels of physical activity and had relatively high levels of stress resilience, yet also high levels of presenteeism. The profiles differed on work affect and health perceptions largely in the expected directions. There were no differences between the profiles in socio-demographics. These results highlight complex within-person interactions between presenteeism, stress resilience, and physical activity in older manual workers. The identification of profiles of older manual workers who are at risk of poor health and functioning may inform targeted interventions to help retain them in the workforce for longer.
Liu, Yao-Wu; Cheng, Ya-Qin; Liu, Xiao-Li; Hao, Yun-Chao; Li, Yu; Zhu, Xia; Zhang, Fan; Yin, Xiao-Xing
2017-08-01
Mangiferin, a natural C-glucoside xanthone, has anti-inflammatory, anti-oxidative, neuroprotective actions. Our previous study showed that mangiferin could attenuate diabetes-associated cognitive impairment of rats by enhancing the function of glyoxalase 1 (Glo-1) in brain. The aim of this study was to investigate whether Glo-1 upregulation by mangiferin in central neurons exposed to chronic high glucose may be related to activation of Nrf2/ARE pathway. Compared with normal glucose (25 mmol/L) culture, Glo-1 protein, mRNA, and activity levels were markedly decreased in primary hippocampal and cerebral cortical neurons cultured with high glucose (50 mmol/L) for 72 h, accompanied by the declined Nrf2 nuclear translocation and protein expression of Nrf2 in cell nucleus, as well as protein expression and mRNA level of γ-glutamylcysteine synthetase (γ-GCS) and superoxide dismutase activity, target genes of Nrf2/ARE signaling. Nonetheless, high glucose cotreating with mangiferin or sulforaphane, a typical inducer of Nrf2 activation, attenuated the above changes in both central neurons. In addition, mangiferin and sulforaphane significantly prevented the formation of advanced glycation end-products (AGEs) reflecting Glo-1 activity, while elevated the level of glutathione, a cofactor of Glo-1 activity and production of γ-GCS, in high glucose cultured central neurons. These findings demonstrated that Glo-1 was greatly downregulated in central neurons exposed to chronic high glucose, which is expected to lead the formation of AGEs and oxidative stress damages. We also proved that mangiferin enhanced the function of Glo-1 under high glucose condition by inducing activation of Nrf2/ARE signaling pathway.
High surface area carbon and process for its production
Romanos, Jimmy; Burress, Jacob; Pfeifer, Peter; Rash, Tyler; Shah, Parag; Suppes, Galen
2016-12-13
Activated carbon materials and methods of producing and using activated carbon materials are provided. In particular, biomass-derived activated carbon materials and processes of producing the activated carbon materials with prespecified surface areas and pore size distributions are provided. Activated carbon materials with preselected high specific surface areas, porosities, sub-nm (<1 nm) pore volumes, and supra-nm (1-5 nm) pore volumes may be achieved by controlling the degree of carbon consumption and metallic potassium intercalation into the carbon lattice during the activation process.
Physical activity barriers and motivators among high-risk employees.
Paguntalan, John C; Gregoski, Mathew
2016-11-22
Worksite wellness programs offer an ideal setting to target high-risk sedentary workers to improve health status. Lack of physical activity is associated with increased risk for coronary heart disease and mortality. Despite the risks, the number of sedentary workers is increasing. This study examined the perceived barriers and motivators for physical activity among employees at high-risk for coronary heart disease. A purposive sample of 24 high-risk workers participating in a wellness program in rural South Carolina were enrolled in the study. Qualitative data was obtained through semi-structured face-to-face interviews. Grounded theory was used to analyze qualitative data, and identify overarching themes. Physical limitations due to pain and weakness, lack of motivation, and lack of time emerged as the main barriers to physical activity. Family relationships were reported as the strongest motivator along with social support and potential health benefits. Findings highlight the unique experience of high-risk workers with physical activity. The findingsunderscore the need to design and implement effective interventions specifically designed to meet the needs of high-risk employees.
Jensen, Chad D; Duraccio, Kara M; Carbine, Kaylie A; Barnett, Kimberly A; Kirwan, C Brock
2017-06-01
To examine associations between motivational impact of palatable foods and neural activity in brain regions involved in inhibitory control among adolescents. Thirty-four adolescents aged 14-20 years underwent functional magnetic resonance imaging while viewing images of high- and low-energy foods. Participants completed the Power of Food Scale (PFS). Whole-brain analyses of variance tested for neural activation differences and correlations between brain activation and PFS scores were tested. We found an interaction between food type (high energy vs. low energy) and PFS scores in the right dorsolateral prefrontal cortex and right inferior parietal lobule. We also found that PFS scores correlated negatively with activation to high-energy foods in prefrontal cortical and parietal regions. These findings suggest that individuals with high motivation for high-energy foods also demonstrate lower neural activation in inhibition-related brain regions when viewing images of high-energy foods, indicating that they may have difficulty inhibiting consumption impulses. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
McCoy, G D
1980-03-01
The aniline hydroxylase activity of microsomes isolated from hamster liver can be differentiated kinetically into high affinity (low K(m), form I) and low affinity (high K(m), form II) forms. Microsomes isolated from uninduced animals contain slightly more form I activity. The activity of the low affinity form (form II) is preferentially enhanced by Aroclor or 3-methylcholanthrene treatment, while phenobarbital treatment increases the activity of both forms. Chronic ethanol consumption results in enhancement of only the high affinity form (form I).
Jung, Yoon Suk; Park, Jung Ho; Park, Dong Il; Sohn, Chong Il; Lee, Jae Myun; Kim, Tae Il
2018-06-01
Several studies have reported relationships among physical activity, healthy metabolic status, and increased natural killer (NK) cell activity. However, large-scale data thereon are lacking. Thus, the present study aimed to assess NK cell activity according to physical activity and metabolic status. A cross-sectional study was performed on 12014 asymptomatic examinees. Using a patented stimulatory cytokine, NK cell activity was quantitated by the amount of interferon-γ secreted into the plasma by NK cells. Physical activity levels were assessed using the validated Korean version of the International Physical Activity Questionnaire Short Form. The physically inactive group showed lower NK cell activity than the minimally active group (median, 1461 vs. 1592 pg/mL, p<0.001) and health-enhancing physically active group (median, 1461 vs. 1712 pg/mL, p=0.001). Compared to women with a body mass index (BMI) of 18.5-27.5 kg/m², those with a BMI <18.5 kg/m² had significantly lower NK cell activity (1356 vs. 1024 g/mL, p<0.001), and those with a BMI ≥27.5 kg/m² tended to have lower NK cell activity (1356 vs. 1119 g/mL, p=0.070). Subjects with high hemoglobin A1c levels and low high-density lipoprotein cholesterol levels, as well as men with high blood pressure and women with high triglyceride levels, exhibited lower NK cell activity. Moreover, physical inactivity and metabolic abnormalities were independently associated with low NK cell activity, even after adjusting for confounders. Physical inactivity and metabolic abnormalities are associated with reduced NK cell activity. Immune systems may become altered depending on physical activity and metabolic status. © Copyright: Yonsei University College of Medicine 2018.
NASA Astrophysics Data System (ADS)
Christensen, Rhonda; Knezek, Gerald; Tyler-Wood, Tandra
2015-12-01
This study examines positive dispositions reported by middle school and high school students participating in programs that feature STEM-related activities. Middle school students participating in school-to-home hands-on energy monitoring activities are compared to middle school and high school students in a different project taking part in activities such as an after-school robotics program. Both groups are compared and contrasted with a third group of high school students admitted at the eleventh grade to an academy of mathematics and science. All students were assessed using the same science, technology, engineering and mathematics (STEM) dispositions instrument. Findings indicate that the after-school group whose participants self-selected STEM engagement activities, and the self-selected academy of mathematics and science group, each had highly positive STEM dispositions comparable to those of STEM professionals, while a subset of the middle school whole-classroom energy monitoring group that reported high interest in STEM as a career, also possessed highly positive STEM dispositions comparable to the STEM Professionals group. The authors conclude that several different kinds of hands-on STEM engagement activities are likely to foster or maintain positive STEM dispositions at the middle school and high school levels, and that these highly positive levels of dispositions can be viewed as a target toward which projects seeking to interest mainstream secondary students in STEM majors in college and STEM careers, can hope to aspire. Gender findings regarding STEM dispositions are also reported for these groups.
NASA Astrophysics Data System (ADS)
2011-05-01
Quantum physics: German Physical Society spring meeting Journal access: American Physical Society's online journals will be available for free in all US high schools Award: High-school physics teacher receives American award for excellence Teacher training: Fobinet offers coordination of teacher-training activities Astronomy: Astronomy fans see stars at Astrofest Conference: Delegates enjoy the workshops and activities at CPD conference Forthcoming events
NASA Astrophysics Data System (ADS)
Sharma, Gopal; Champati ray, P. K.; Mohanty, S.
2018-01-01
Alaknanda basin in the Garhwal Himalaya, India, is a tectonically active region owing to ongoing crustal deformation, erosion, and depositional processes active in the region. Active tectonics in this region have greatly affected the drainage system and geomorphic expression of topography and provide an ideal natural set up to investigate the influence of tectonic activity resulting from the India-Eurasia collision. We evaluated active tectonics by using high resolution digital elevation model (DEM) based on eight geomorphic indices (stream length gradient index, valley floor width-to-height ratio, hypsometric integral, drainage basin asymmetry, transverse topography symmetry factor, mountain front sinousity index, bifurcation ratio, and basin shape index) and seismicity in eight subbasins of Alaknanda basin. The integrated product, relative tectonic activity index (TAI) map, was classified into three classes such as: 'highly active' with values ranging up to 2.0; 'moderately active' with values ranging from 2.0 to 2.25; and 'less active' with values > 2.25. Further, the results were compared with relatively high crustal movement rate of 41.10 mm/y computed through high precession Global Navigation Satellite System (GNSS) based continuous operating reference station (CORS) data. Thus, we concluded that this new quantitative approach can be used for better characterization and assessment of active seismotectonic regions of the Himalaya and elsewhere.
NASA Astrophysics Data System (ADS)
Manocha, S.; Manocha, L. M.; Joshi, Parth; Patel, Bhavesh; Dangi, Gaurav; Verma, Narendra
2013-06-01
Activated carbon are unique and versatile adsorbents having extended surface area, micro porous structure, universal adsorption effect, high adsorption capacity and high degree of surface reactivity. Activated carbons are synthesized from variety of materials. Most commonly used on a commercial scale are cellulosic based precursors such as peat, coal, lignite wood and coconut shell. Variation occurs in precursors in terms of structure and carbon content. Coir having very low bulk density and porous structure is found to be one of the valuable raw materials for the production of highly porous activated carbon and other important factor is its high carbon content. Exploration of good low cost and non conventional adsorbent may contribute to the sustainability of the environment and offer promising benefits for the commercial purpose in future. Carbonization of biomass was carried out in a horizontal muffle furnace. Both carbonization and activation were performed in inert nitrogen atmosphere in one step to enhance the surface area and to develop interconnecting porosity. The types of biomass as well as the activation conditions determine the properties and the yield of activated carbon. Activated carbon produced from biomass is cost effective as it is easily available as a waste biomass. Activated carbon produced by combination of chemical and physical activation has higher surface area of 2442 m2/gm compared to that produced by physical activation (1365 m2/gm).
Li, Xi; Higashida, Kazuhiko; Kawamura, Takuji; Higuchi, Mitsuru
2016-04-06
Long-term high-fat diet increases muscle mitochondrial enzyme activity and endurance performance. However, excessive calorie intake causes intra-abdominal fat accumulation and metabolic syndrome. The purpose of this study was to investigate the effect of an alternating day high-fat diet on muscle mitochondrial enzyme activities, protein content, and intra-abdominal fat mass in rats. Male Wistar rats were given a standard chow diet (CON), high-fat diet (HFD), or alternate-day high-fat diet (ALT) for 4 weeks. Rats in the ALT group were fed a high-fat diet and standard chow every other day for 4 weeks. After the dietary intervention, mitochondrial enzyme activities and protein content in skeletal muscle were measured. Although body weight did not differ among groups, the epididymal fat mass in the HFD group was higher than those of the CON and ALT groups. Citrate synthase and beta-hydroxyacyl CoA dehydrogenase activities in the plantaris muscle of rats in HFD and ALT were significantly higher than that in CON rats, whereas there was no difference between HFD and ALT groups. No significant difference was observed in muscle glycogen concentration or glucose transporter-4 protein content among the three groups. These results suggest that an alternate-day high-fat diet induces increases in mitochondrial enzyme activities and protein content in rat skeletal muscle without intra-abdominal fat accumulation.
Gaitán-Cepeda, Luis Alberto; Sánchez-Vargas, Octavio; Castillo, Nydia
2015-08-01
SummaryHighly active antiretroviral therapy has decreased the morbidity and mortality related to HIV infection, including oral opportunistic infections. This paper offers an analysis of the scientific literature on the epidemiological aspects of oral candidiasis in HIV-positive children in the combination antiretroviral therapy era. An electronic databases search was made covering the highly active antiretroviral therapy era (1998 onwards). The terms used were oral lesions, oral candidiasis and their combination with highly active antiretroviral therapy and HIV/AIDS children. The following data were collected from each paper: year and country in which the investigation was conducted, antiretroviral treatment, oral candidiasis prevalence and diagnostic parameters (clinical or microbiological). Prevalence of oral candidiasis varied from 2.9% in American HIV-positive children undergoing highly active antiretroviral therapy to 88% in Chilean HIV-positive children without antiretroviral therapy. With respect to geographical location and antiretroviral treatment, higher oral candidiasis prevalence in HIV-positive children on combination antiretroviral therapy/antiretroviral therapy was reported in African children (79.1%) followed by 45.9% reported in Hindu children. In HIV-positive Chilean children on no antiretroviral therapy, high oral candidiasis prevalence was reported (88%) followed by Nigerian children (80%). Oral candidiasis is still frequent in HIV-positive children in the highly active antiretroviral therapy era irrespective of geographical location, race and use of antiretroviral therapy. © The Author(s) 2014.
Price, J A
1998-08-01
An occasional but difficult problem arises in drug discovery during a chromatographic analysis in which high background activity is associated with the presence of most eluting molecular species. This makes the isolation of material of high relative activity difficult. A computational method is shown that clarifies the identification of regions of the chromatogram of interest. The data for bioactivity and absorbance are normalized to percent of maximal response, filtered to raise very small or zero values to a minimal level, and the activity/absorbance ratio is plotted per fraction. The fractions with relatively high activity become evident. This technique is a helpful adjunct to existing graphical methods and provides an objective relationship between the data sets. It is simple to implement with Visual Basic and spreadsheet data, making it widely accessible.
NASA Astrophysics Data System (ADS)
Wang, Shan; Gao, Shasha; Tang, Yakun; Wang, Lei; Jia, Dianzeng; Liu, Lang
2018-04-01
Coal-based activated carbons (AC) were acted as the support, Cu/AC catalysts were synthesized by a facile solid-state reaction combined with subsequent heat treatment. In Cu/AC composites, highly dispersed Cu nanospheres were anchored on AC. The catalytic activity for 4-nitrophenol (4-NP) was investigated, the effects of activation temperature and copper loading on the catalytic performance were studied. The catalysts exhibited very high catalytic activity and moderate chemical stability due to the unique characteristics of the particle-assembled nanostructures, the high surface area and the porous structure of coal-based AC and the good dispersion of metal particles. Design and preparation of non-noble metal composite catalysts provide a new direction for improving the added value of coal.
Systemic lupus erythematosus patients in the low-latitude plateau of China: altitudinal influences.
Qian, G; Ran, X; Zhou, C X; Deng, D Q; Zhang, P L; Guo, Y; Luo, J H; Zhou, X H; Xie, H; Cai, M
2014-12-01
The current study was to investigate the features of hospitalized patients with systemic lupus erythematosus (SLE) at different altitudes. The correlation between SLE activity and altitudinal variations was also explored. Medical records of 1029 patients were retrospectively reviewed. Activity of SLE in each organ system was recorded using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). There was no significant correlation between SLE activity and altitudes (r = 0.003, p = 0.159). Age at onset for SLE patients at high altitudes was significantly younger than that at low and moderate altitudes (p = 0.022 and p = 0.004, respectively). Age at SLE admission at low altitudes was significant older than those at moderate and high altitudes (p = 0.011 and p < 0.001, respectively). Patients at high altitudes had shorter duration from disease onset to admission than those at moderate altitudes (p = 0.009). Incidence of Sm antibodies-positive for resident patients at high altitudes was 36.4%, which were higher than that at moderate altitudes (p = 0.003). We found increasing trends of CNS activity in active patients; immunological and renal activities in inactive patients were correlated with elevated altitudes (p = 0.024, p = 0.004, p = 0.005), while arthritis scores in active patients showed the tendency of decreasing with the rise of elevation (p = 0.002). Hemoglobin level, red blood cell and platelet counts at high altitudes were significantly lower than those at low altitudes (p < 0.05, respectively). There was no significant difference in hemoglobin level between moderate- and low-altitude groups (p > 0.05). No significant difference in platelet counts between moderate- and high-altitude groups was observed (p > 0.05). Our findings suggest that some clinical features, laboratory tests and activity of main organs in SLE are influenced by altitudes. Furthermore, organ activities of active and inactive SLE patients have different patterns of altitudinal variations. These distinctive variations likely reveal that peculiar environmental factors at high altitudes can affect the development of SLE. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Hyndman, Kelly A; Mironova, Elena V; Giani, Jorge F; Dugas, Courtney; Collins, Jessika; McDonough, Alicia A; Stockand, James D; Pollock, Jennifer S
2017-10-24
During high sodium intake, the renin-angiotensin-aldosterone system is downregulated and nitric oxide signaling is upregulated in order to remain in sodium balance. Recently, we showed that collecting duct nitric oxide synthase 1β is critical for fluid-electrolyte balance and subsequently blood pressure regulation during high sodium feeding. The current study tested the hypothesis that high sodium activation of the collecting duct nitric oxide synthase 1β pathway is critical for maintaining sodium homeostasis and for the downregulation of the renin-angiotensin-aldosterone system-epithelial sodium channel axis. Male control and collecting duct nitric oxide synthase 1β knockout (CDNOS1KO) mice were placed on low, normal, and high sodium diets for 1 week. In response to the high sodium diet, plasma sodium was significantly increased in control mice and to a significantly greater level in CDNOS1KO mice. CDNOS1KO mice did not suppress plasma aldosterone in response to the high sodium diet, which may be partially explained by increased adrenal AT1R expression. Plasma renin concentration was appropriately suppressed in both genotypes. Furthermore, CDNOS1KO mice had significantly higher intrarenal angiotensin II with high sodium diet, although intrarenal angiotensinogen levels and angiotensin-converting enzyme activity were similar between knockout mice and controls. In agreement with inappropriate renin-angiotensin-aldosterone system activation in the CDNOS1KO mice on a high sodium diet, epithelial sodium channel activity and sodium transporter abundance were significantly higher compared with controls. These data demonstrate that high sodium activation of collecting duct nitric oxide synthase 1β signaling induces suppression of systemic and intrarenal renin-angiotensin-aldosterone system, thereby modulating epithelial sodium channel and other sodium transporter abundance and activity to maintain sodium homeostasis. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Liu, Hong; Zhang, Yujin; Wu, Hongyu; D'Alessandro, Angelo; Yegutkin, Gennady G; Song, Anren; Sun, Kaiqi; Li, Jessica; Cheng, Ning-Yuan; Huang, Aji; Edward Wen, Yuan; Weng, Ting Ting; Luo, Fayong; Nemkov, Travis; Sun, Hong; Kellems, Rodney E; Karmouty-Quintana, Harry; Hansen, Kirk C; Zhao, Bihong; Subudhi, Andrew W; Jameson-Van Houten, Sonja; Julian, Colleen G; Lovering, Andrew T; Eltzschig, Holger K; Blackburn, Michael R; Roach, Robert C; Xia, Yang
2016-08-02
High altitude is a challenging condition caused by insufficient oxygen supply. Inability to adjust to hypoxia may lead to pulmonary edema, stroke, cardiovascular dysfunction, and even death. Thus, understanding the molecular basis of adaptation to high altitude may reveal novel therapeutics to counteract the detrimental consequences of hypoxia. Using high-throughput, unbiased metabolomic profiling, we report that the metabolic pathway responsible for production of erythrocyte 2,3-bisphosphoglycerate (2,3-BPG), a negative allosteric regulator of hemoglobin-O2 binding affinity, was significantly induced in 21 healthy humans within 2 hours of arrival at 5260 m and further increased after 16 days at 5260 m. This finding led us to discover that plasma adenosine concentrations and soluble CD73 activity rapidly increased at high altitude and were associated with elevated erythrocyte 2,3-BPG levels and O2 releasing capacity. Mouse genetic studies demonstrated that elevated CD73 contributed to hypoxia-induced adenosine accumulation and that elevated adenosine-mediated erythrocyte A2B adenosine receptor activation was beneficial by inducing 2,3-BPG production and triggering O2 release to prevent multiple tissue hypoxia, inflammation, and pulmonary vascular leakage. Mechanistically, we demonstrated that erythrocyte AMP-activated protein kinase was activated in humans at high altitude and that AMP-activated protein kinase is a key protein functioning downstream of the A2B adenosine receptor, phosphorylating and activating BPG mutase and thus inducing 2,3-BPG production and O2 release from erythrocytes. Significantly, preclinical studies demonstrated that activation of AMP-activated protein kinase enhanced BPG mutase activation, 2,3-BPG production, and O2 release capacity in CD73-deficient mice, in erythrocyte-specific A2B adenosine receptor knockouts, and in wild-type mice and in turn reduced tissue hypoxia and inflammation. Together, human and mouse studies reveal novel mechanisms of hypoxia adaptation and potential therapeutic approaches for counteracting hypoxia-induced tissue damage. © 2016 American Heart Association, Inc.
Aeromechanical Evaluation of Smart-Twisting Active Rotor
NASA Technical Reports Server (NTRS)
Lim, Joon W.; Boyd, D. Douglas, Jr.; Hoffman, Frauke; van der Wall, Berend G.; Kim, Do-Hyung; Jung, Sung N.; You, Young H.; Tanabe, Yasutada; Bailly, Joelle; Lienard, Caroline;
2014-01-01
An investigation of Smart-Twisting Active Rotor (STAR) was made to assess potential benefits of the current active twist rotor concept for performance improvement, vibration reduction, and noise alleviation. The STAR rotor is a 40% Mach-scaled, Bo105 rotor with an articulated flap-lag hinge at 3.5%R and no pre-cone. The 0-5 per rev active twist harmonic inputs were applied for various flight conditions including hover, descent, moderate to high speed level flights, and slowed rotor high advance ratio. For the analysis, the STAR partners used multiple codes including CAMRAD II, S4, HOST, rFlow3D, elsA, and their associated software. At the high thrust level in hover, the 0 per rev active twist with 80% amplitude increased figure of merit (FM) by 0.01-0.02 relative to the baseline. In descent, the largest BVI noise reduction was on the order of 2 to 5 dB at the 3 per rev active twist. In the high speed case (mu = 0.35), the 2 per rev actuation was found to be the most effective in achieving a power reduction as well as a vibration reduction. At the 2 per rev active twist, total power was reduced by 0.65% at the 60 deg active twist phase, and vibration was reduced by 47.6% at the 45 deg active twist phase. The use of the 2 per rev active twist appears effective for vibration reduction. In the high advance ratio case (mu = 0.70), the 0 per rev actuation appeared to have negligible impact on performance improvement. In summary, computational simulations successfully demonstrated that the current active twist concept provided a significant reduction of the maximum BVI noise in descent, a significant reduction of the vibration in the high speed case, a small improvement on rotor performance in hover, and a negligible impact on rotor performance in forward flight.
Lyu, Shurong; Su, Jian; Xiang, Quanyong; Wu, Ming
2014-08-01
Our study aims to explore the association between dietary patterns and physical activity levels (PAL) with a triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio, and to examine whether the association is sex dependent among Chinese adults. In this cross-sectional study, data were collected through questionnaires, anthropometric measurement, and biochemical tests. Four food patterns ("meat," "healthy," "high-energy," and "traditional Chinese") were established through factor analysis. Physical activity level was categorized as "active," "moderate," and "inactive." Logistic regression models were used to determine the associations between food patterns and PAL with TG/HDL-C ratio. Compared with quartile 1, quartiles 2 and 3 of meat pattern among men were found to be associated with lower risk of high TG/HDL-C ratio (the highest quartile of TG/HDL-C ratio). Similar decreased risk of high TG/HDL-C ratio was also observed in the highest quartile 4 of healthy pattern among women. Active PAL was protective against high TG/HDL-C ratio among both men (odds ratio [OR], 0.69; 95% confidence interval [CI], 0.55-0.86) and women (OR, 0.77; 95% CI, 0.62-0.96). Although no statistically significant interaction was observed, we found that individuals with active PAL and low healthy diet had a similar OR with those with inactive PAL and high healthy diet (0.62 vs 0.68). In conclusion, dietary patterns were associated with TG/HDL-C ratio in a sex-specific way, and active PAL was consistently related to decreased risk of high TG/HDL-C ratio across genders. Copyright © 2014 Elsevier Inc. All rights reserved.
Watanabe, Mika; Kato, Jun; Inoue, Izumi; Yoshimura, Noriko; Yoshida, Takeichi; Mukoubayashi, Chizu; Deguchi, Hisanobu; Enomoto, Shotaro; Ueda, Kazuki; Maekita, Takao; Iguchi, Mikitaka; Tamai, Hideyuki; Utsunomiya, Hirotoshi; Yamamichi, Nobutake; Fujishiro, Mitsuhiro; Iwane, Masataka; Tekeshita, Tatsuya; Mohara, Osamu; Ushijima, Toshikazu; Ichinose, Masao
2012-12-01
This study aimed to elucidate groups at high risk of developing cancer among patients with serologically identified Helicobacter pylori infection and nonatrophic stomach. Annual endoscopy was performed for a mean of 5.4 years in 496 asymptomatic middle-aged men who were H. pylori antibody-positive and pepsinogen (PG) test-negative. Subjects were stratified according to the activity of H. pylori-associated gastritis measured by serum levels of PG and H. pylori antibody, and/or by endoscopic findings of rugal hyperplastic gastritis (RHG), and cancer development was investigated. During the study period, seven cases of cancer developed in the cohort (incidence rate, 261/100,000 person-years), with 85.7% developing in the group showing a PGI/II ratio ≤ 3.0, reflecting active inflammation-based high PGII levels. Cancer incidence was significantly higher in this group (750/100,000 person-years) than in groups with less active gastritis. Furthermore, cancer incidence for this group was significantly higher in the subgroup with high H. pylori antibody titers than in the low-titer subgroup. Meanwhile, endoscopic findings revealed that 11.7% of subjects showed RHG reflecting localized highly active inflammation, and cancer risk was significantly higher in patients with RHG than in patients without. Combining the two serum tests and endoscopic examination for RHG allowed identification of subjects with more active gastritis and higher cancer risk. No cancer development was observed in these high-risk subjects after H. pylori eradication. Subjects with highly active gastritis identified by the two serological tests and endoscopic RHG constitute a group at high risk of cancer development with H. pylori-infected nonatrophic stomach. Copyright © 2012 UICC.
Nitric oxide contributes to high-salt perception in a blood-sucking insect model.
Cano, Agustina; Pontes, Gina; Sfara, Valeria; Anfossi, Diego; Barrozo, Romina B
2017-11-14
In all organisms, salts produce either appetitive or aversive responses depending on the concentration. While low-salt concentration in food elicits positive responses to ingest, high-salt triggers aversion. Still the mechanisms involved in this dual behavior have just started to be uncovered in some organisms. In Rhodnius prolixus, using pharmacological and behavioral assays, we demonstrated that upon high-salt detection in food a nitric oxide (NO) dependent cascade is activated. This activation involves a soluble guanylate cyclase (sGC) and the production of cyclic guanosine monophosphate (cGMP). Thus, appetitive responses to low-salt diets turn to aversion whenever this cascade is activated. Conversely, insects feed over aversive high-salt solutions when it is blocked by reducing NO levels or by affecting the sGC activity. The activation of NO/sGC/cGMP cascade commands the avoidance feeding behavior in R. prolixus. Investigations in other insect species should examine the possibility that high-salt aversion is mediated by NO/sSG/cGMP signaling.
Influences of lifestyle factors on cardiac autonomic nervous system activity over time.
Hu, Mandy Xian; Lamers, Femke; de Geus, Eco J C; Penninx, Brenda W J H
2017-01-01
Physical activity, alcohol use and smoking might affect cardiovascular disease through modifying autonomic nervous system (ANS) activity. We investigated: 1) whether there are consistent relationships between lifestyle factors and cardiac ANS activity over time, and 2) whether 2-year changes in lifestyle factors relate to 2-year changes in cardiac activity. Baseline (n=2618) and 2-year follow-up (n=2010) data of the Netherlands Study of Depression and Anxiety was combined. Baseline data was collected in the Netherlands from 2004-2007. Lifestyle factors were habitual physical activity, frequency of sport activities, alcohol use, and smoking. Indicators of cardiac activity were heart rate (HR), respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP) (100min of registration). The results showed that high physical activity (-1.8beats/min compared to low activity), high frequency of sport activities ('couple of times/week': -2.5beats/min compared to 'almost never') and mild/moderate alcohol use (-1.2beats/min compared to non-drinking) were related to low HR. Heavy smoking was related to high HR (>30cigarettes/day: +5.1beats/min compared to non-smoking). High frequency of sport activities was associated with high RSA ('couple of times/week':+1.7ms compared to 'almost never') and moderate smoking with longer PEP (11-20cigarettes/day: +2.8ms compared to non-smoking). Associations were consistent across waves. Furthermore, 2-year change in frequency of sport activities and number of smoked cigarettes/day was accompanied by 2-year change in HR (β=-0.076 and β=0.101, respectively) and RSA (β=0.046 and β=-0.040, respectively). Our findings support consistent effects of lifestyle on HR and parasympathetic activity in the expected direction. Cardiac autonomic dysregulation may be partly mediating the relationship between lifestyle and subsequent cardiovascular health. Copyright © 2016 Elsevier Inc. All rights reserved.
Gubelmann, Cédric; Vollenweider, Peter; Marques-Vidal, Pedro
2017-12-01
Determinants of the interplay between physical activity (PA) and sedentary (SE) status are poorly known. We assessed the socio-economic determinants of PA and SE behaviours and patterns in a population-based study (The CoLaus study, Lausanne, Switzerland, 2014-2017). 2229 adults (51.8% women, age range 45-86 years) had PA and SE levels measured for 14 days using a wrist-worn accelerometer. Four activity behaviours: (1) 'Couch potato': low PA & high SE; (2) 'Light mover': low PA & low SE; (3) 'Sedentary exerciser': high PA & high SE, and (4) 'Busy bee': high PA & low SE; and three activity patterns: (1) 'Inactive', (2) 'Weekend warrior', and (3) 'Regularly active' were defined. Employment, household income and educational level were collected by questionnaire. For activity behaviours, relative to 'Couch potatoes', multivariate analysis showed that being employed and having a low educational level were positively associated with 'Light movers': relative risk ratios and (95% confidence interval): 1.54 (1.00-2.37) and 1.73 (1.11-2.69), respectively, and also with 'Busy bees': 1.49 (1.09-2.04) and 1.71 (1.26-2.32), respectively. High household income was negatively associated with 'Light movers': 0.58 (0.34-0.97) and positively with 'Sedentary exercisers': 1.85 (1.10-3.10). For activity patterns, relative to 'Inactives', being employed and having a high household income were positively associated with 'Weekend warriors': 1.78 (1.26-2.50) and 1.59 (1.07-2.36), respectively, while having a low educational level was positively associated with 'Regularly actives': 1.76 (1.32-2.34). Employment, educational level and household income are significantly but differently associated with activity behaviours and patterns. Copyright © 2017 Elsevier Inc. All rights reserved.
2009-09-01
capable of surviving the high-temperature, high- vibration environment of a jet engine. Active control spans active surge/stall control and three...other closely related areas, viz., active combustion control (references 21-22), active noise control, and active vibration control. All of these are...self-powered sensors that harvest energy from engine heat or vibrations replace sensors that require power. The long-term vision is one of a
Pieters, Marlien; Oosthuizen, Welma; Jerling, Johann C; Loots, Du Toit; Mukuddem-Petersen, Janine; Hanekom, Susanna M
2005-09-01
We investigated the effect of a high walnut and cashew diet on haemostatic variables in people with the metabolic syndrome. Factor analysis was used to determine how the haemostatic variables cluster with other components of the metabolic syndrome and multiple regression to determine possible predictors. This randomized, control, parallel, controlled-feeding trial included 68 subjects who complied with the Third National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol criteria. After a 3-week run-in following the control diet, subjects were divided into three groups receiving either walnuts or cashews (20 energy%) or a control diet for 8 weeks. The nut intervention had no significant effect on von Willebrand factor antigen, fibrinogen, factor VII coagulant activity, plasminogen activator inhibitor 1 activity, tissue plasminogen activator activity or thrombin activatable fibrinolysis inhibitor. Statistically, fibrinogen clustered with the body-mass-correlates and acute phase response factors, and factor VII coagulant activity clustered with high-density lipoprotein cholesterol (HDL-C). Tissue plasminogen activator activity, plasminogen activator inhibitor 1 activity and von Willebrand factor antigen clustered into a separate endothelial function factor. HDL-C and markers of obesity were the strongest predictors of the haemostatic variables. We conclude that high walnut and cashew diets did not influence haemostatic factors in this group of metabolic syndrome subjects. The HDL-C increase and weight loss may be the main focus of dietary intervention for the metabolic syndrome. Furthermore, diet composition may have only limited effects if weight loss is not achieved.
Relationships between solar activity and climate change
NASA Technical Reports Server (NTRS)
Roberts, W. O.
1975-01-01
The relationship between recurrent droughts in the High Plains of the United States and the double sunspot cycle is discussed in detail. It is suggested that high solar activity is generally related to an increase in meridional circulation and blocking patterns at high and intermediate latitudes, especially in winter, and the effect is related to the sudden formation of cirrus clouds during strong geomagnetic activity that originates in the solar corpuscular emission.
Environmental Education Activities Manual, Book 5: Junior High Activities.
ERIC Educational Resources Information Center
Stapp, William B., Ed.; Cox, Dorothy A., Ed.
This activities book for the junior high level is the fifth book of a series of six books designed to provide developmental K-12 experiences designed to support the basic environmental philosophy of spaceship earth presented in Book 1. The aims of the four activity sections of this book are to aid in developing students to make them more sensitive…
Environmental Education Activities Manual, Book 6: Senior High Activities.
ERIC Educational Resources Information Center
Stapp, William B., Ed.; Cox, Dorothy A., Ed.
This activities book for the senior high school level is the sixth book of a series of six books designed to provide developmental K-12 experiences designed to support the basic environmental philosophy of spaceship earth presented in Book 1. The aims of the four activity sections of this book are to aid in developing students to make them more…
Self-optimizing, highly surface-active layered metal dichalcogenide catalysts for hydrogen evolution
NASA Astrophysics Data System (ADS)
Liu, Yuanyue; Wu, Jingjie; Hackenberg, Ken P.; Zhang, Jing; Wang, Y. Morris; Yang, Yingchao; Keyshar, Kunttal; Gu, Jing; Ogitsu, Tadashi; Vajtai, Robert; Lou, Jun; Ajayan, Pulickel M.; Wood, Brandon C.; Yakobson, Boris I.
2017-09-01
Low-cost, layered transition-metal dichalcogenides (MX2) based on molybdenum and tungsten have attracted substantial interest as alternative catalysts for the hydrogen evolution reaction (HER). These materials have high intrinsic per-site HER activity; however, a significant challenge is the limited density of active sites, which are concentrated at the layer edges. Here we unravel electronic factors underlying catalytic activity on MX2 surfaces, and leverage the understanding to report group-5 MX2 (H-TaS2 and H-NbS2) electrocatalysts whose performance instead mainly derives from highly active basal-plane sites, as suggested by our first-principles calculations and performance comparisons with edge-active counterparts. Beyond high catalytic activity, they are found to exhibit an unusual ability to optimize their morphology for enhanced charge transfer and accessibility of active sites as the HER proceeds, offering a practical advantage for scalable processing. The catalysts reach 10 mA cm-2 current density at an overpotential of ˜50-60 mV with a loading of 10-55 μg cm-2, surpassing other reported MX2 candidates without any performance-enhancing additives.
Effects of active recovery during interval training on plasma catecholamines and insulin.
Nalbandian, Harutiun M; Radak, Zsolt; Takeda, Masaki
2018-06-01
BACKGROUNDː Active recovery has been used as a method to accelerate the recovery during intense exercise. It also has been shown to improve performance in subsequent exercises, but little is known about its acute effects on the hormonal and metabolic profile. The aim of this research was to study the effects of active recovery on plasma catecholamines and plasma insulin during a high-intensity interval exercise. METHODSː Seven subjects performed two high-intensity interval training protocols which consisted of three 30-second high-intensity bouts (constant intensity), separated by a recovery of 4 minutes. The recovery was either active recovery or passive recovery. During the main test blood samples were collected and plasma insulin, plasma catecholamines and blood lactate were determined. Furthermore, respiratory gasses were also measured. RESULTSː Plasma insulin and blood lactate were significantly higher in the passive recovery trial, while plasma adrenaline was higher in the active recovery. Additionally, VO2 and VCO2 were significantly more increased during the active recovery trials. CONCLUSIONSː These results suggest that active recovery affects the hormonal and metabolic responses to high-intensity interval exercise. Active recovery produces a hormonal environment which may favor lipolysis and oxidative metabolism, while passive recovery may be favoring glycolysis.
Adenylyl cyclase G is activated by an intramolecular osmosensor.
Saran, Shweta; Schaap, Pauline
2004-03-01
Adenylyl cyclase G (ACG) is activated by high osmolality and mediates inhibition of spore germination by this stress factor. The catalytic domains of all eukaryote cyclases are active as dimers and dimerization often mediates activation. To investigate the role of dimerization in ACG activation, we coexpressed ACG with an ACG construct that lacked the catalytic domain (ACGDeltacat) and was driven by a UV-inducible promoter. After UV induction of ACGDeltacat, cAMP production by ACG was strongly inhibited, but osmostimulation was not reduced. Size fractionation of native ACG showed that dimers were formed between ACG molecules and between ACG and ACGDeltacat. However, high osmolality did not alter the dimer/monomer ratio. This indicates that ACG activity requires dimerization via a region outside the catalytic domain but that dimer formation does not mediate activation by high osmolality. To establish whether ACG required auxiliary sensors for osmostimulation, we expressed ACG cDNA in a yeast adenylyl cyclase null mutant. In yeast, cAMP production by ACG was similarly activated by high osmolality as in Dictyostelium. This strongly suggests that the ACG osmosensor is intramolecular, which would define ACG as the first characterized primary osmosensor in eukaryotes.
Spatial patterns of high Aedes aegypti oviposition activity in northwestern Argentina.
Estallo, Elizabet Lilia; Más, Guillermo; Vergara-Cid, Carolina; Lanfri, Mario Alberto; Ludueña-Almeida, Francisco; Scavuzzo, Carlos Marcelo; Introini, María Virginia; Zaidenberg, Mario; Almirón, Walter Ricardo
2013-01-01
In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. Oviposition activity was detected in Orán City (Salta province) using ovitraps, weekly replaced (October 2005-2007). Spatial autocorrelation was measured with Moran's Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR) sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC=0.77), obtaining 99% of sensitivity and 75.29% of specificity. Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist National Health Ministry to focus resources more effectively.
Bermúdez, Valmore; Aparicio, Daniel; Rojas, Edward; Peñaranda, Lianny; Finol, Freddy; Acosta, Luis; Mengual, Edgardo; Rojas, Joselyn; Arráiz, Nailet; Toledo, Alexandra; Colmenares, Carlos; Urribarí, Jesica; Sanchez, Wireynis; Pineda, Carlos; Rodriguez, Dalia; Faria, Judith; Añez, Roberto; Cano, Raquel; Cano, Clímaco; Sorell, Luis; Velasco, Manuel
2010-01-01
Coronary artery disease is the main cause of death worldwide. Lipoprotein(a) [Lp(a)], is an independent risk factor for coronary artery disease in which concentrations are genetically regulated. Contradictory results have been published about physical activity influence on Lp(a) concentration. This research aimed to determine associations between different physical activity levels and Lp(a) concentration. A descriptive and cross-sectional study was made in 1340 randomly selected subjects (males = 598; females = 712) to whom a complete clinical history, the International Physical Activity Questionnaire, and Lp(a) level determination were made. Statistical analysis was carried out to assess qualitative variables relationship by chi2 and differences between means by one-way analysis of variance considering a P value <0.05 as statistically significant. Results are shown as absolute frequencies, percentages, and mean +/- standard deviation according to case. Physical activity levels were ordinal classified as follows: low activity with 24.3% (n = 318), moderate activity with 35.0% (n = 458), and high physical activity with 40.8% (n = 534). Lp(a) concentration in the studied sample was 26.28 +/- 12.64 (IC: 25.59-26.96) mg/dL. Lp(a) concentration according to low, moderate, and high physical activity levels were 29.22 +/- 13.74, 26.27 +/- 12.91, and 24.53 +/- 11.35 mg/dL, respectively, observing statistically significant differences between low and moderate level (P = 0.004) and low and high level (P < 0.001). A strong association (chi2 = 9.771; P = 0.002) was observed among a high physical activity level and a normal concentration of Lp(a) (less than 30 mg/dL). A lifestyle characterized by high physical activity is associated with normal Lp(a) levels.
Van Ettinger-Veenstra, Helene; McAllister, Anita; Lundberg, Peter; Karlsson, Thomas; Engström, Maria
2016-01-01
This study investigates the relation between individual language ability and neural semantic processing abilities. Our aim was to explore whether high-level language ability would correlate to decreased activation in language-specific regions or rather increased activation in supporting language regions during processing of sentences. Moreover, we were interested if observed neural activation patterns are modulated by semantic incongruency similarly to previously observed changes upon syntactic congruency modulation. We investigated 27 healthy adults with a sentence reading task-which tapped language comprehension and inference, and modulated sentence congruency-employing functional magnetic resonance imaging (fMRI). We assessed the relation between neural activation, congruency modulation, and test performance on a high-level language ability assessment with multiple regression analysis. Our results showed increased activation in the left-hemispheric angular gyrus extending to the temporal lobe related to high language ability. This effect was independent of semantic congruency, and no significant relation between language ability and incongruency modulation was observed. Furthermore, there was a significant increase of activation in the inferior frontal gyrus (IFG) bilaterally when the sentences were incongruent, indicating that processing incongruent sentences was more demanding than processing congruent sentences and required increased activation in language regions. The correlation of high-level language ability with increased rather than decreased activation in the left angular gyrus, a region specific for language processing, is opposed to what the neural efficiency hypothesis would predict. We can conclude that no evidence is found for an interaction between semantic congruency related brain activation and high-level language performance, even though the semantic incongruent condition shows to be more demanding and evoking more neural activation.
Van Ettinger-Veenstra, Helene; McAllister, Anita; Lundberg, Peter; Karlsson, Thomas; Engström, Maria
2016-01-01
This study investigates the relation between individual language ability and neural semantic processing abilities. Our aim was to explore whether high-level language ability would correlate to decreased activation in language-specific regions or rather increased activation in supporting language regions during processing of sentences. Moreover, we were interested if observed neural activation patterns are modulated by semantic incongruency similarly to previously observed changes upon syntactic congruency modulation. We investigated 27 healthy adults with a sentence reading task—which tapped language comprehension and inference, and modulated sentence congruency—employing functional magnetic resonance imaging (fMRI). We assessed the relation between neural activation, congruency modulation, and test performance on a high-level language ability assessment with multiple regression analysis. Our results showed increased activation in the left-hemispheric angular gyrus extending to the temporal lobe related to high language ability. This effect was independent of semantic congruency, and no significant relation between language ability and incongruency modulation was observed. Furthermore, there was a significant increase of activation in the inferior frontal gyrus (IFG) bilaterally when the sentences were incongruent, indicating that processing incongruent sentences was more demanding than processing congruent sentences and required increased activation in language regions. The correlation of high-level language ability with increased rather than decreased activation in the left angular gyrus, a region specific for language processing, is opposed to what the neural efficiency hypothesis would predict. We can conclude that no evidence is found for an interaction between semantic congruency related brain activation and high-level language performance, even though the semantic incongruent condition shows to be more demanding and evoking more neural activation. PMID:27014040
Seasonal distribution of bird populations at the Patuxent Research Refuge
Hoffman, D.J.; Henny, C.J.; Hill, E.F.; Keith, J.A.; Grove, R.A.
2000-01-01
High concentrations of mercury from past mining activities have accumulated in the food chain of fish-eating birds nesting along the mid to lower Carson River. Activities of nine plasma and tissue enzymes, and concentrations of other plasma and tissue constituents were measured for black-crowned night-heron, Nycticorax nycticorax, (BCNH) and snowy egret, Egretta thula, (SE) nestlings from two high mercury sites and one low mercury site. Geometric mean blood Hg concentrations for BCNHs at the high mercury sites were 2.6 and 2.8 ppm (ww) and 0.6 ppm at the low mercury site. Blood concentrations for SEs were 3.6 and 1.9 ppm at the high mercury sites and 0.7 ppm at the low mercury site. In BCNHs plasma glutathione peroxidase (GSH peroxidase) activity was lower in both high mercury sites relative to the low mercury site. Butyryl cholinesterase (BuChe), ALT, glutathione reductase (GSSG-reductase) and LDH-L activities were lower in one high mercury site. In SEs significant differences were lower BuChe and LDH-L, but elevated GGT activities. Evidence of renal stress in both species at high mercury sites included increased plasma uric acid, blood urea nitrogen, and creatinine concentrations as well as oxidative stress in the kidney tissue itself where oxidized glutathione increased. A number of the mercury site-related effects, including decreased plasma GSH-peroxidase and hepatic G-6-PDH activities, higher GSSG-reductase activity, and lower hepatic concentrations of reduced thiols have been reported in methylmercury feeding studies with great egrets and mallards. These findings suggest the utility of herons and egrets for monitoring mercury sites.
Altered prefrontal brain activity in persons at risk for Alzheimer's disease: an fMRI study.
Elgh, Eva; Larsson, Anne; Eriksson, Sture; Nyberg, Lars
2003-06-01
Early diagnosis of Alzheimer's disease (AD) is critical for adequate treatment and care. Recently it has been shown that functional magnetic resonance imaging (fMRI) can be important in preclinical detection of AD. The purpose of this study was to examine possible differences in memory-related brain activation between persons with high versus low risk for AD. This was achieved by combining a validated neurocognitive screening battery (the 7-minutes test) with memory assessment and fMRI. One hundred two healthy community-living persons with subjective memory complaints were recruited through advertisement and tested with the 7-minutes test. Based on their test performance they were classified as having either high (n = 8) or low risk (n = 94) for AD. Six high-risk individuals and six age-, sex-, and education-matched low-risk individuals were investigated with fMRI while engaged in episodic memory tasks. The high-risk individuals performed worse than low-risk individuals on tests of episodic memory. Patterns of brain activity during episodic encoding and retrieval showed significant group differences (p < .05 corrected). During both encoding and retrieval, the low-risk persons showed increased activity relative to a baseline condition in prefrontal brain regions that previously have been implicated in episodic memory. By contrast, the high-risk persons did not significantly activate any prefrontal regions, but instead showed increased activity in visual occipito-temporal regions. Patterns of prefrontal brain activity related to episodic memory differ between persons with high versus low risk for AD, and lowered prefrontal activity may predict subsequent disease.
Integrated Nutrition Education: Senior High.
ERIC Educational Resources Information Center
Illinois State Board of Education, Springfield.
Designed for implementation across the school year in existing curriculum areas, 18 nutrition activity units for high school students are provided. Each activity unit consists of a list of coordinated curriculum areas, a statement of objectives, guidelines for teachers, a list of learning activities, and bibliographic citations. Various…
Rueggeberg, Rebecca; Wrosch, Carsten; Miller, Gregory E.
2011-01-01
This 4-yr longitudinal study examined the different roles of perceived stress in the association between older adults’ physical activities and physical health. We hypothesized that physical activities would exert beneficial effects on physical health by preventing chronically high levels of perceived stress. Design and Measures We assessed baseline levels of physical activities and repeated measures of perceived stress and physical symptoms in three waves of data from a sample of 157 older adults. Results Among participants with high (but not low) baseline levels of perceived stress, physical activity predicted a 2-yr reduction of perceived stress and a 4-yr prevention of physical health symptoms. Moreover, the interaction effect on 4-yr changes in physical symptoms was mediated by 2-yr changes in perceived stress. Conclusions Physical health benefits of physical activity are particularly pronounced among older adults who perceive high levels of stress, and this effect is mediated by a prevention of chronically high perceptions of stress. PMID:21875206
The prospects for life on Mars - A pre-Viking assessment
NASA Technical Reports Server (NTRS)
Sagan, C.; Lederberg, J.
1976-01-01
The paper considers implications of the Mariner 9 findings for the investigation of Martian biology in the next decade, beginning with the Viking mission. Previous claims for observations of Martian biological activity are reviewed and refuted or reinterpreted. The question is raised of whether there are combinations of environmental temperature and water activity on Mars that are suitable for a conceivable Martian biology. Four possible classes of Martian organisms associated with temperature/water ecological niches in the external environment are proposed: organisms requiring high temperatures and high water activity, those inhabiting niches with low temperatures and high water activity, those inhabiting niches of high temperature and low water activity, and those which can survive under conditions of low temperature and low water activity. It is noted that organisms of the last two classes may extract water from minerals or from ice and may be of large dimensions. The possible surface distribution of Martian organisms is discussed along with future search strategies for life on Mars.
Effect of high surface area activated carbon on thermal degradation of jet fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gergova, K.; Eser, S.; Arumugam, R.
1995-05-01
Different solid carbons added to jet fuel during thermal stressing cause substantial changes in pyrolytic degradation reactions. Activated carbons, especially high surface area activated carbons were found to be very effective in suppressing solid deposition on metal reactor walls during stressing at high temperatures (425 and 450{degrees}C). The high surface area activated carbon PX-21 prevented solid deposition on reactor walls even after 5h at 450{degrees}C. The differences seen in the liquid product composition when activated carbon is added indicated that the carbon surfaces affect the degradation reactions. Thermal stressing experiments were carried out on commercial petroleum-derived JPTS jet fuel. Wemore » also used n-octane and n-dodecane as model compounds in order to simplify the study of the chemical changes which take place upon activated carbon addition. In separate experiments, the presence of a hydrogen donor, decalin, together with PX-21 was also studied.« less
Mace, Jonathan L.; Seitz, Gerald J.; Bronisz, Lawrence E.
2016-10-25
Detonation control modules and detonation control circuits are provided herein. A trigger input signal can cause a detonation control module to trigger a detonator. A detonation control module can include a timing circuit, a light-producing diode such as a laser diode, an optically triggered diode, and a high-voltage capacitor. The trigger input signal can activate the timing circuit. The timing circuit can control activation of the light-producing diode. Activation of the light-producing diode illuminates and activates the optically triggered diode. The optically triggered diode can be coupled between the high-voltage capacitor and the detonator. Activation of the optically triggered diode causes a power pulse to be released from the high-voltage capacitor that triggers the detonator.
ERIC Educational Resources Information Center
Dawson, Jeffrey R.; And Others
This monograph was designed for the high school biology curriculum. The first section reviews the major areas of importance in immunology. Section three contains six instructional activities for the high school classroom and the second section contains teacher's materials for those activities. The activities address for students some of the major…
Guerrero, Cecilia; Vera, Carlos; Conejeros, Raúl; Illanes, Andrés
2015-03-01
β-Galactosidases exhibit both hydrolytic and transgalactosylation activities; the former has been used traditionally for the production of delactosed milk and dairies, while the latter is being increasingly used for the synthesis of lactose-derived oligosaccharides: balance between both activities was highly dependent on the enzyme origin: β-galactosidases from Aspegillus oryzae and Bacillus circulans exhibited high transgalactosylation activity, while those from one from Kluyveromyces exhibited high hydrolytic activity but quite low transgalactosylation activity. Also the affinity for the donors (lactose or lactulose) and the acceptors (lactose, lactulose or fructose) of transgalactosylated galactose was dependent on the enzyme origin, as reflected by the Michaelis constants obtained in the synthesis of galacto-oligosaccharides, fructosyl-galacto-oligosaccharides and lactulose. Finally, the balance between transgalactosylation and hydrolytic activities of β-galactosidases could be tuned by changing the concentration of galactose donor. Copyright © 2014 Elsevier Inc. All rights reserved.
Antioxidant activity and antibacterial activity of peach gum derived oligosaccharides.
Yao, Xing-Cun; Cao, Yan; Wu, Sheng-Jun
2013-11-01
In this study, peach gum derived oligosaccharides (PGDO) were prepared from peach gum polysaccharides by hydrolysis using hydrogen peroxide (H2O2) under following conditions: time, 8h; temperature, 55 °C; H2O2 concentration, 4% (v/v); and NaOH concentration, 2.0 M. The antioxidant activity and antibacterial activity of PGDO were estimated. There were no significant chemical changes in the backbones of the peach gum polysaccharides treated with H2O2. The PGDO showed high hydroxyl radical scavenging activity (86.12%) and 2, 2-diphenyl-β-picrylhydrazyl radical scavenging activity (91.70%) at the concentration of 100 μg/mL as well as high reducing capacity at the concentration of 50 μg/mL. In addition the PGDO had high antibacterial activity against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli at the concentration of 100 μg/mL. Copyright © 2013 Elsevier B.V. All rights reserved.
High expression of osteoglycin decreases gelatinase activity of murine hepatocarcinoma Hca-F cells
Cui, Xiao-Nan; Tang, Jian-Wu; Song, Bo; Wang, Bo; Chen, Shan-Yan; Hou, Li
2009-01-01
AIM: To investigate the possible correlation between osteoglycin expression and gelatinase activity of mouse hepatocarcinoma Hca-F cells. METHODS: A eukaryotic expression plasmid pIRESpuro3 osteoglycin(+) was constructed and transfected into Hca-F cells to investigate the possible correlation between osteoglycin expression and gelatinase activity of Hca-F cells cultured with extract of lymph node, liver, spleen or in DMEM medium. The activity of gelatinases was examined through zymographic analysis. RESULTS: High expression of osteoglycin attenuated the gelatinase activity of Hca-F cells cultured with extract of lymph node, and at the same time, decreased the metastatic potential of Hca-F cells to peripheral lymph nodes in vivo. CONCLUSION: High expression of osteoglycin decreases the gelatinase activity of Hca-F cells cultured with extract of lymph node; regulation of gelatinase activity might be one of mechanisms that osteoglycin contributes to lymphatic metastasis suppression. PMID:20027687
Attenuating the mortality risk of high serum uric acid: the role of physical activity underused.
Chen, Jiunn-Horng; Wen, Chi Pang; Wu, Shiuan Bei; Lan, Joung-Liang; Tsai, Min Kuang; Tai, Ya-Ping; Lee, June Han; Hsu, Chih Cheng; Tsao, Chwen Keng; Wai, Jackson Pui Man; Chiang, Po Huang; Pan, Wen Han; Hsiung, Chao Agnes
2015-11-01
High serum uric acid (sUA) has been associated with increased mortality risks, but its clinical treatment varied with potential side effects. The role of physical activity has received limited attention. A cohort, consisting of 467 976 adults, who went through a standard health screening programme, with questionnaire and fasting blood samples, was successively recruited between 1996 and 2008. High sUA is defined as uric acid above 7.0 mg/dL. Leisure time physical activity level was self-reported, with fully active defined as those with 30 min per day for at least 5 days a week. National death file identified 12 228 deaths with a median follow-up of 8.5 years. Cox proportional model was used to analyse HRs, and 12 variables were controlled, including medical history, life style and risk factors. High sUA constituted one quarter of the cohort (25.6%). Their all-cause mortality was significantly increased [HR: 1.22 (1.15-1.29)], with much of the increase contributed to by the inactive (HR: 1.27 (1.17-1.37)), relative to the reference group with sUA level of 5-6 mg/dL. When they were fully active, mortality risks did not increase, but decreased by 11% (HR: 0.89 (0.82-0.97)), reflecting the benefits of being active was able to overcome the adverse effects of high sUA. Given the same high sUA, a 4-6 years difference in life expectancy was found between the active and the inactive. Physical activity is a valuable alternative to pharmacotherapy in its ability to reduce the increases in mortality risks from high sUA. By being fully active, exercise can extend life span by 4-6 years, a level greater than the 1-4 years of life-shortening effect from high sUA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Ou, Guanyong; Wang, Hong; Si, Ranran; Guan, Wanchun
2017-09-01
Due to global climate change, marine phytoplankton will likely experience low pH (ocean acidification), high temperatures and high irradiance in the future. Here, this work report the results of a batch culture experiment conducted to study the interactive effects of elevated CO 2 , increased temperature and high irradiance on the harmful dinoflagellate Akashiwo sanguinea, isolated at Dongtou Island, Eastern China Sea. The A. sanguinea cells were acclimated in high CO 2 condition for about three months before testing the responses of cells to a full factorial matrix experimentation during a 7-day period. This study measured the variation in physiological parameters and hemolytic activity in 8 treatments, representing full factorial combinations of 2 levels each of exposure to CO 2 (400 and 1000μatm), temperature (20 and 28°C) and irradiance (50 and 200μmol photons m -2 s -1 ). Sustained growth of A. sanguinea occurred in all treatments, but high CO 2 (HC) stimulated faster growth than low CO 2 (LC). The pigments (chlorophyll a and carotenoid) decreased in all HC treatments. The quantum yield (F v /F m ) declined slightly in all high-temperature (HT) treatments. High irradiance (HL) induced the accumulation of ultraviolet-absorbing compounds (UV abc ) irrespective of temperature and CO 2 . The hemolytic activity in the LC treatments, however, declined when exposed to HT and HL, but HC alleviated the adverse effects of HT and HL on hemolytic activity. All HC and HL conditions and the combinations of high temperature*high light (HTHL) and high CO 2 *high temperature*high light (HCHTHL) positively affected the growth in comparison to the low CO 2 *low temperature*low light (LCLTLL) treatment. High temperature (HT), high light (HL) and a combination of HT*HL, however, negatively impacted hemolytic activity. CO 2 was the main factor that affected the growth and hemolytic activity. There were no significant interactive effects of CO 2 *temperature*irradiance on growth, pigment, F v /F m or hemolytic activity, but there were effects on P m , α, and E k . If these results are extrapolated to the natural environment, it can be hypothesized that A. sanguinea cells will benefit from the combination of ocean acidification, warming, and high irradiance that are likely to occur under future climate change. It is assumed that faster growth and higher hemolytic activity and UV abc of this species will occur under future conditions compared with those the current CO 2 (400μatm) and temperature (20°C) conditions. Copyright © 2017 Elsevier B.V. All rights reserved.
Development of a New De Novo Design Algorithm for Exploring Chemical Space.
Mishima, Kazuaki; Kaneko, Hiromasa; Funatsu, Kimito
2014-12-01
In the first stage of development of new drugs, various lead compounds with high activity are required. To design such compounds, we focus on chemical space defined by structural descriptors. New compounds close to areas where highly active compounds exist will show the same degree of activity. We have developed a new de novo design system to search a target area in chemical space. First, highly active compounds are manually selected as initial seeds. Then, the seeds are entered into our system, and structures slightly different from the seeds are generated and pooled. Next, seeds are selected from the new structure pool based on the distance from target coordinates on the map. To test the algorithm, we used two datasets of ligand binding affinity and showed that the proposed generator could produce diverse virtual compounds that had high activity in docking simulations. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Kobayashi, Naoki; Maeda, Eriko; Saito, Shioko; Furukawa, Ichiro; Ohnishi, Takahiro; Watanabe, Maiko; Terajima, Jun; Hara-Kudo, Yukiko
2016-01-01
The characteristics of 11 strains of Stx1-producing and Stx2-non-producing STEC O103:H2 were analyzed to investigate the differences in virulence in a single serotype of Shiga toxin (Stx) -producing Escherichia coli (STEC). Differences in the cell-adhesion activity to Caco-2 cells were observed among the strains. The activity of the one strain, isolated from a patient with hemolytic uremic syndrome was 4-20-fold higher than those of the other strains. Although the strains with high cell-adhesion activity showed high expressions of eae, espB, espD, and tir in the locus of enterocyte effacement related with cell-adhesion, those were not specific for this strain. In addition, the Stx1 production level of the strain was not particularly high. It was indicated that the high adhesion activity might be a potential factor to associate serious symptom.
Compassionate love buffers stress-reactive mothers from fight-or-flight parenting.
Miller, Jonas G; Kahle, Sarah; Lopez, Monica; Hastings, Paul D
2015-01-01
The links among mothers' compassionate love for their child, autonomic nervous system activity, and parenting behavior during less and more challenging mother-child interactions were examined. Mothers expressed and reported less negative affect when they exhibited autonomic patterns of increased parasympathetic dominance (high parasympathetic and low sympathetic activation) or autonomic coactivation (high parasympathetic and high sympathetic activation) during the less challenging interaction and autonomic coactivation during the more challenging interaction. Compassionate love predicted less reported and observed negativity in mothers who showed increased sympathetic nervous system dominance (high sympathetic and low parasympathetic activation). Compassionate love appeared to help mothers, and particularly those who experienced strong physiological arousal during difficult parenting situations, establish positive socialization contexts for their children and avoid stress-induced adverse parenting.
High capacity anode materials for lithium ion batteries
Lopez, Herman A.; Anguchamy, Yogesh Kumar; Deng, Haixia; Han, Yongbon; Masarapu, Charan; Venkatachalam, Subramanian; Kumar, Suject
2015-11-19
High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.
Calorimetric method for determination of {sup 51}Cr neutrino source activity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Veretenkin, E. P., E-mail: veretenk@inr.ru; Gavrin, V. N.; Danshin, S. N.
Experimental study of nonstandard neutrino properties using high-intensity artificial neutrino sources requires the activity of the sources to be determined with high accuracy. In the BEST project, a calorimetric system for measurement of the activity of high-intensity (a few MCi) neutrino sources based on {sup 51}Cr with an accuracy of 0.5–1% is created. In the paper, the main factors affecting the accuracy of determining the neutrino source activity are discussed. The calorimetric system design and the calibration results using a thermal simulator of the source are presented.
Utilizing waste activated sludge for animal feeding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beszedits, S.
1981-01-01
Activated sludge has a high protein content and is a good source of B-group vitamins and generally also of minerals (Ca, Mg, Fe and K). Propionibacterium freudenreichii can be readily incorporated into the activated sludge to synthesize vitamin B12, particularly high vitamin yields being obtained with sewage mixed with dairy waste. Numerous examples of successful use of activated sludge in animal feeding are given.
NASA Astrophysics Data System (ADS)
Zhang, J.
2016-12-01
There is a high temperature hydrothermal activity area in the western plateau of Sichuan. More than 200 hot springs points have been found in the region, including 11 hot spring water temperature above local boiling point. Most of these distribute along Jinshajjiang fracture, Dege-Xiangcheng fracture, Ganzi-Litang fracture as well as Xianshuihe fracture, and form three high-temperature hydrothermal activity strips in the NW-SE direction. Using gravity, magnetic, seismic and helium isotope data, this paper analyzed the crust-mantle heat flow structure, crustal heat source distribution and water heating system. The results show that the geothermal activity mainly controlled by the "hot" crust. The ratio of crustal heat flow and surface heat flow is higher than 60%. In the high temperature hydrothermal activities area, there is lower S wave velocity zone with Vs<3.2 km/s in 15 30 km depth in middle and lower crust. Basing on the S wave velocity inversion temperature of crust-mantle, it has been found that there is a high temperature layer with 850 1000 ° in 20 40 km depth. It is the main heat source of high temperature hydrothermal activity area of western Sichuan. Our argument is that atmospheric precipitation, surface water infiltrated along the fault fracture into the crustal deep, heating by crustal hot source, and circulation to surface become high temperature hot water. Geothermal water mainly reserve in the Triassic strata of the containing water good carbonate rocks, and in the intrusive granite which is along the fault zone. The thermal energy of Surface heat thermal activities mainly comes from the high-temperature hot source which is located in the middle and lower crust. Being in the deep crustal fracture, the groundwater infiltrated to the deep crust and absorbed heat, then, quickly got back to the surface and formed high hot springs.
Das, Falguni; Ghosh-Choudhury, Nandini; Dey, Nirmalya; Bera, Amit; Mariappan, Meenalakshmi M.; Kasinath, Balakuntalam S.; Ghosh Choudhury, Goutam
2014-01-01
High glucose-induced Akt acts as a signaling hub for mesangial cell hypertrophy and matrix expansion, which are recognized as cardinal signatures for the development of diabetic nephropathy. How mesangial cells sustain the activated state of Akt is not clearly understood. Here we show Akt-dependent phosphorylation of the transcription factor FoxO1 by high glucose. Phosphorylation-deficient, constitutively active FoxO1 inhibited the high glucose-induced phosphorylation of Akt to suppress the phosphorylation/inactivation of PRAS40 and mTORC1 activity. In contrast, dominant negative FoxO1 increased the phosphorylation of Akt, resulting in increased mTORC1 activity similar to high glucose treatment. Notably, FoxO1 regulates high glucose-induced protein synthesis, hypertrophy, and expression of fibronectin and PAI-1. High glucose paves the way for complications of diabetic nephropathy through the production of reactive oxygen species (ROS). We considered whether the FoxO1 target antioxidant enzyme catalase contributes to sustained activation of Akt. High glucose-inactivated FoxO1 decreases the expression of catalase to increase the production of ROS. Moreover, we show that catalase blocks high glucose-stimulated Akt phosphorylation to attenuate the inactivation of FoxO1 and PRAS40, resulting in the inhibition of mTORC1 and mesangial cell hypertrophy and fibronectin and PAI-1 expression. Finally, using kidney cortices from type 1 diabetic OVE26 mice, we show that increased FoxO1 phosphorylation is associated with decreased catalase expression and increased fibronectin and PAI-1 expression. Together, our results provide the first evidence for the presence of a positive feedback loop for the sustained activation of Akt involving inactivated FoxO1 and a decrease in catalase expression, leading to increased ROS and mesangial cell hypertrophy and matrix protein expression. PMID:25288788
DOE Office of Scientific and Technical Information (OSTI.GOV)
Desjardins, Y.; Beeson, R.; Gosselin, A.
1989-04-01
Standard growing conditions in vitro (low light and CO{sub 2}) are not conducive to autotrophy. An experiment was conducted to improve photosynthesis in vitro in the hope of increasing survival in acclimatization. A factorial experiment was elaborated where CO{sub 2} and PPFD were supplied to in vitro cultured strawberry plants in the rooting stage. Activities of carboxylating enzymes were determined after 4 weeks of culture. The activities of non-activated and activated rubisco and PEP-Case were measured after extraction of the enzymes and a reaction with NaH{sup 14}CO{sub 3} followed by scintillation counting spectroscopy. High CO{sub 2} concentration significantly increased netmore » assimilation rates (NAR) by 165% over the control for both 1650 and 3000 ppm CO{sub 2}. High PPFD only increased NAR by 12 and 35% for 150 and 250 {mu}mol{center dot}m{sup {minus}2}{center dot}s{sup {minus}1} respectively over the control. Plants grown at 3000 ppm CO{sub 2} had the highest level of chlorophyll/g FW with 97% more than the control. The activity of PEP-Case was the highest at high light levels and high CO{sub 2} with rates of 1.65 for 1650 ppm versus 1.22 mmol CO{sub 2} mg{sup {minus}1} chl. h{sup {minus}1} at 250 {mu}mol{center dot}m{sup {minus}2}{center dot}s{sup {minus}1}. There was no difference in PEP activity at low light levels. The rubisco activity was lower at 1650 and 3000 ppm CO{sub 2}. Increases in NAR correlate more closely to the PEP-Case than to Rubisco activity. Physiological significance of high activity of PEP-Case over rubisco will be discussed.« less
George, Thampi; Watts, Bruns A.
2011-01-01
A high sodium intake increases the capacity of the medullary thick ascending limb (MTAL) to absorb HCO3−. Here, we examined the role of the apical NHE3 and basolateral NHE1 Na+/H+ exchangers in this adaptation. MTALs from rats drinking H2O or 0.28 M NaCl for 5–7 days were perfused in vitro. High sodium intake increased HCO3− absorption rate by 60%. The increased HCO3− absorptive capacity was mediated by an increase in apical NHE3 activity. Inhibiting basolateral NHE1 with bath amiloride eliminated 60% of the adaptive increase in HCO3− absorption. Thus the majority of the increase in NHE3 activity was dependent on NHE1. A high sodium intake increased basolateral Na+/H+ exchange activity by 89% in association with an increase in NHE1 expression. High sodium intake increased apical Na+/H+ exchange activity by 30% under conditions in which basolateral Na+/H+ exchange was inhibited but did not change NHE3 abundance. These results suggest that high sodium intake increases HCO3− absorptive capacity in the MTAL through 1) an adaptive increase in basolateral NHE1 activity that results secondarily in an increase in apical NHE3 activity; and 2) an adaptive increase in NHE3 activity, independent of NHE1 activity. These studies support a role for NHE1 in the long-term regulation of renal tubule function and suggest that the regulatory interaction whereby NHE1 enhances the activity of NHE3 in the MTAL plays a role in the chronic regulation of HCO3− absorption. The adaptive increases in Na+/H+ exchange activity and HCO3− absorption in the MTAL may play a role in enabling the kidneys to regulate acid-base balance during changes in sodium and volume balance. PMID:21613418
Legget, Kristina T; Cornier, Marc-Andre; Rojas, Donald C; Lawful, Benjamin; Tregellas, Jason R
2015-08-01
In our increasingly obesogenic environment, in which high-calorie convenience foods are readily available, food choices can drastically affect weight and overall health. Learned food preferences, which are developed through repeated pairings with positively and negatively valenced stimuli, can contribute to obesity susceptibility if positive attitudes toward high-calorie foods are developed. Thus, the modification of automatic associations with food may be a viable strategy to promote healthier eating behaviors. In this study, we investigated the ability of an implicit priming (IP) intervention to alter responses to visual food cues by using an evaluative conditioning approach. The main objective was to implicitly (i.e., below conscious perception) associate disgust with high-calorie foods with the aim of reducing liking of these foods. Participants were randomly assigned to active or control IP. In active IP (n = 22), high-calorie food images were implicitly primed with negatively valenced images, and low-calorie food images were implicitly primed with positively valenced images. In control IP (n = 20), all food images were primed with neutral images of fixation crosses. Food images were rated on the desire to eat immediately before and after IP. A significant main effect of calorie (high compared with low; P < 0.001) and a significant calorie-by-group (active compared with control) interaction (P = 0.025) were observed. Post hoc tests identified a significantly greater high-calorie rating decline after active IP than after control IP (P = 0.036). Furthermore, there was significantly greater change in high-calorie ratings than in low-calorie ratings in the active group (P = 0.001). Active IP effects extended to high-calorie foods not specifically included in the intervention, which suggested an effect generalization. Moreover, a greater change in high-calorie ratings than in low-calorie ratings persisted 3-5 d after active IP (P < 0.007), which suggested lasting effects. This study provides initial evidence that IP can be used to alter high-calorie food preferences, which could promote healthier eating habits. © 2015 American Society for Nutrition.
Duiverman, Marieke L; Huberts, Anouk S; van Eykern, Leo A; Bladder, Gerrie; Wijkstra, Peter J
2017-01-01
Introduction High-intensity noninvasive ventilation (NIV) has been shown to improve outcomes in stable chronic obstructive pulmonary disease patients. However, there is insufficient knowledge about whether with this more controlled ventilatory mode optimal respiratory muscle unloading is provided without an increase in patient–ventilator asynchrony (PVA). Patients and methods Ten chronic obstructive pulmonary disease patients on home mechanical ventilation were included. Four different ventilatory settings were investigated in each patient in random order, each for 15 min, varying the inspiratory positive airway pressure and backup breathing frequency. With surface electromyography (EMG), activities of the intercostal muscles, diaphragm, and scalene muscles were determined. Furthermore, pressure tracings were derived simultaneously in order to assess PVA. Results Compared to spontaneous breathing, the most pronounced decrease in EMG activity was achieved with the high-pressure settings. Adding a high breathing frequency did reduce EMG activity per breath, while the decrease in EMG activity over 1 min was comparable with the high-pressure, low-frequency setting. With high backup breathing frequencies less breaths were pressure supported (25% vs 97%). PVAs occurred more frequently with the low-frequency settings (P=0.017). Conclusion High-intensity NIV might provide optimal unloading of respiratory muscles, without undue increases in PVA. PMID:28138234
Duiverman, Marieke L; Huberts, Anouk S; van Eykern, Leo A; Bladder, Gerrie; Wijkstra, Peter J
2017-01-01
High-intensity noninvasive ventilation (NIV) has been shown to improve outcomes in stable chronic obstructive pulmonary disease patients. However, there is insufficient knowledge about whether with this more controlled ventilatory mode optimal respiratory muscle unloading is provided without an increase in patient-ventilator asynchrony (PVA). Ten chronic obstructive pulmonary disease patients on home mechanical ventilation were included. Four different ventilatory settings were investigated in each patient in random order, each for 15 min, varying the inspiratory positive airway pressure and backup breathing frequency. With surface electromyography (EMG), activities of the intercostal muscles, diaphragm, and scalene muscles were determined. Furthermore, pressure tracings were derived simultaneously in order to assess PVA. Compared to spontaneous breathing, the most pronounced decrease in EMG activity was achieved with the high-pressure settings. Adding a high breathing frequency did reduce EMG activity per breath, while the decrease in EMG activity over 1 min was comparable with the high-pressure, low-frequency setting. With high backup breathing frequencies less breaths were pressure supported (25% vs 97%). PVAs occurred more frequently with the low-frequency settings ( P =0.017). High-intensity NIV might provide optimal unloading of respiratory muscles, without undue increases in PVA.
ERIC Educational Resources Information Center
Sesen, Burcin Acar; Tarhan, Leman
2013-01-01
This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental (N =…
ERIC Educational Resources Information Center
Zavacky, Francesca; Michael, Shannon L.
2017-01-01
Recess is an important part of a comprehensive school physical activity program by providing physical activity to students during the school day, in addition to physical education and classroom physical activity. Unfortunately, recess in the United States is not an expected part of the school day, especially in middle and high schools. High-stakes…
Outdoor Recreation Activities at Cispus.
ERIC Educational Resources Information Center
Cispus Environmental Center, Randle, WA.
Most of the activities in this booklet have been developed around skills related to the outdoors and, in particular, to the logging industry and forest fire fighting. The activities attempt to develop muscles, coordination skills, and teamwork. They also give the students (junior high school or high school) and staff the opportunity to do…
Project Water Science. General Science High School Level.
ERIC Educational Resources Information Center
Water Education Foundation, Sacramento, CA.
This teacher's guide presents 12 hands-on laboratory activities for high school science classes that cover the environmental issue of water resources in California. The activities are separated into three sections. Five activities in the section on water quality address the topics of groundwater, water hardness, bottled water, water purity, and…
Purpose and Meaning in Highly Active Seniors
ERIC Educational Resources Information Center
Penick, Jeffrey M.; Fallshore, Marte
2005-01-01
The authors investigated the sources of meaning for active seniors. Results indicated that seniors who were most active were relatively high in a wide range of sources of meaning as well as in life satisfaction in general. The importance of meaning and purpose in relation to counseling with older adults is discussed.
Alternative High School Students' Physical Activity: Role of Self-Efficacy
ERIC Educational Resources Information Center
Kenyon, Denyelle Baete; Kubik, Martha Y.; Davey, Cynthia; Sirard, John; Fulkerson, Jayne A.
2012-01-01
Objective: To examine physical activity self-efficacy as a mediator of the association between perceived barriers to PA and moderate-to-vigorous physical activity (MVPA) among alternative high school (AHS) students. Methods: Students (N = 145) from 6 AHS completed self-report questionnaires. Results: Mediation analyses revealed partial mediation…
An Evaluation of a Wide Range of Job-Generating Activities for Rural Counties.
ERIC Educational Resources Information Center
Finsterbusch, Kurt; And Others
1992-01-01
Examines the job-generating activities in 15 rural counties in Maryland through 175 interviews and field work. Those ranking high included industrial park development, economic development activities, and tourism. Special financial arrangements for relocating and new businesses also received high marks. Includes 48 references. (JOW)
Social power and approach-related neural activity
Smolders, Ruud; Cremer, David De
2012-01-01
It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power. PMID:19304842
Social power and approach-related neural activity.
Boksem, Maarten A S; Smolders, Ruud; De Cremer, David
2012-06-01
It has been argued that power activates a general tendency to approach whereas powerlessness activates a tendency to inhibit. The assumption is that elevated power involves reward-rich environments, freedom and, as a consequence, triggers an approach-related motivational orientation and attention to rewards. In contrast, reduced power is associated with increased threat, punishment and social constraint and thereby activates inhibition-related motivation. Moreover, approach motivation has been found to be associated with increased relative left-sided frontal brain activity, while withdrawal motivation has been associated with increased right sided activations. We measured EEG activity while subjects engaged in a task priming either high or low social power. Results show that high social power is indeed associated with greater left-frontal brain activity compared to low social power, providing the first neural evidence for the theory that high power is associated with approach-related motivation. We propose a framework accounting for differences in both approach motivation and goal-directed behaviour associated with different levels of power.
Yasuda, Ryohei; Harvey, Christopher D; Zhong, Haining; Sobczyk, Aleksander; van Aelst, Linda; Svoboda, Karel
2006-02-01
To understand the biochemical signals regulated by neural activity, it is necessary to measure protein-protein interactions and enzymatic activity in neuronal microcompartments such as axons, dendrites and their spines. We combined two-photon excitation laser scanning with fluorescence lifetime imaging to measure fluorescence resonance energy transfer at high resolutions in brain slices. We also developed sensitive fluorescent protein-based sensors for the activation of the small GTPase protein Ras with slow (FRas) and fast (FRas-F) kinetics. Using FRas-F, we found in CA1 hippocampal neurons that trains of back-propagating action potentials rapidly and reversibly activated Ras in dendrites and spines. The relationship between firing rate and Ras activation was highly nonlinear (Hill coefficient approximately 5). This steep dependence was caused by a highly cooperative interaction between calcium ions (Ca(2+)) and Ras activators. The Ras pathway therefore functions as a supersensitive threshold detector for neural activity and Ca(2+) concentration.
Li, Xiaoxia; Song, Yimeng; Han, Yingying; Wang, Dawei; Zhu, Yi
2012-08-01
Liver X receptors (LXRs) are key regulators of cholesterol homeostasis. Synthetic LXR agonists are anti-atherogenic and anti-inflammatory. However, the effect of LXR agonists on endothelial progenitor cell (EPC) function is largely unknown. Here, we explored the effect of the LXR agonist TO901317 (TO) on EPC biology and the underlying mechanisms. Endothelial progenitor cells were cultured in mannitol or 30 mm glucose (high glucose) for 24 hours. For TO treatments, cells were pretreated with TO (10 μm) for 12 hours, then mannitol or high glucose was added for an additional 24 hours. EPCs function, reactive oxygen species (ROS) release, and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) were analyzed. TO could restore the high glucose-impaired adhesion and migration capacity of EPCs. High glucose impaired EPC-mediated angiogenesis, and TO reversed the impairment. TO also alleviated ROS release induced by high glucose. Western blot analysis revealed that high glucose downregulated the phosphorylation of AMPK and endothelial nitric oxide synthase, which could be reversed with TO treatment. Furthermore, inhibiting AMPK activation by compound C could abolish the protective effects of TO on EPCs. TO had a protective effect on EPCs under high glucose by inhibiting ROS release and activating AMPK. © 2012 John Wiley & Sons Ltd.
Fleck, Jessica I.; Green, Deborah L.; Stevenson, Jennifer L.; Payne, Lisa; Bowden, Edward M.; Jung-Beeman, Mark; Kounios, John
2008-01-01
Transliminality reflects individual differences in the threshold at which unconscious processes or external stimuli enter into consciousness. Individuals high in transliminality possess characteristics such as magical ideation, belief in the paranormal, and creative personality traits, and also report the occurrence of manic/mystic experiences. The goal of the present research was to determine if resting brain activity differs for individuals high versus low in transliminality. We compared baseline EEG recordings (eyes-closed) between individuals high versus low in transliminality, assessed using The Revised Transliminality Scale of Lange et al. (2000). Identifying reliable differences at rest between high- and low-transliminality individuals would support a predisposition for transliminality-related traits. Individuals high in transliminality exhibited lower alpha, beta, and gamma power than individuals low in transliminality over left posterior association cortex and lower high alpha, low beta, and gamma power over the right superior temporal region. In contrast, when compared to individuals low in transliminality, individuals high in transliminality exhibited greater gamma power over the frontal-midline region. These results are consistent with prior research reporting reductions in left temporal/parietal activity, as well as the desynchronization of right temporal activity in schizotypy and related schizophrenia spectrum disorders. Further, differences between high- and low-transliminality groups extend existing theories linking altered hemispheric asymmetries in brain activity to a predisposition toward schizophrenia, paranormal beliefs, and unusual experiences. PMID:18814870
Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.
Highlights: •AVP induces mTOR phosphorylation in A-10 cells cultured in high glucose concentration. •The mTOR phosphorylation is mediated by the PI3K/Akt pathway activation. •The AVP-induced mTOR phosphorylation inhibited autophagy and stimulated cell proliferation. -- Abstract: Mammalian target of rapamycin (mTOR) complex is a key regulator of autophagy, cell growth and proliferation. Here, we studied the effects of arginine vasopressin (AVP) on mTOR activation in vascular smooth muscle cells cultured in high glucose concentration. AVP induced the mTOR phosphorylation in A-10 cells grown in high glucose, in contrast to cells cultured in normal glucose; wherein, only basal phosphorylation was observed. Themore » AVP-induced mTOR phosphorylation was inhibited by a PI3K inhibitor. Moreover, the AVP-induced mTOR activation inhibited autophagy and increased thymidine incorporation in cells grown in high glucose. This increase was abolished by rapamycin which inhibits the mTORC1 complex formation. Our results suggest that AVP stimulates mTOR phosphorylation by activating the PI3K/Akt signaling pathway and, subsequently, inhibits autophagy and raises cell proliferation in A-10 cells maintained in high glucose concentration.« less
de Kock, A; Malan, L; Potgieter, J C; Steenekamp, W; van der Merwe, M T
2012-05-01
Psychosocial stress relating to an urban environment or acculturation increases the prevalence of metabolic syndrome (MetS). The objectives of this study were firstly to indicate and compare differences regarding appraisal of stress or active coping responses in urban African (n=88) and Caucasian (n=101) male teachers of South Africa, in accord with the prevalence of MetS indicators. And secondly to investigate the extent to which utilisation of active coping responses, together with MetS indicators, predict target organ damage, in these men. The Coping Strategy Indicator determined high and low active coping responses in male teachers from the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study. SABPA inclusion and exclusion criteria were used. Additionally, diabetic medication users (n=8), and participants with renal impairment (n=2) or HIV positive (n=13), were excluded. MetS indicators included glucose, triglyceride, high-density lipoprotein cholesterol, blood pressure, and waist circumference, independent of confounders (age, physical activity, gamma glutamyl transferase). Microalbuminuria and carotid intima-media thickness indicated target organ damage. More MetS indicators exceeded the IDF cut-off points in high active coping African men (14.71%) than in their Caucasian counterparts (3.33%), as determined from χ² analyses. Furthermore, stepwise regressions indicated that more MetS indicators predicted endothelial dysfunction, especially in the high active coping African men. High active coping African men showed more manifestation of MetS, compared to their Caucasian counterparts, and revealed progress towards endothelial dysfunction. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.
Physical activity level and associated factors among civil servants in Xi'an, China.
Sun, Lijun; Jiang, Xun; Zhao, Xin; Zhang, Yuhai; Xu, Yongyong; Shang, Lei
2016-08-01
This study investigated physical activity levels and associated factors among civil servants in Xi'an, China, to provide reference data for the implementation of health improvement strategies among civil servants. A cross-section study. A random sample of 1000 civil servants aged 18-60 years and employed by the Xi'an civic government was assessed by using the Chinese version of the International Physical Activity Questionnaire. Associations between physical activity and sociodemographic characteristics, family history of chronic disease, and existing disease were evaluated by the Mann-Whitney U-test, Kruskal-Wallis H-test, and binary logistic regression. The response rate was 92.4%. The median physical activity score was 2227 metabolic equivalents of task (MET) minutes per week (interquartile range [IQR]: 1308-3802METmin/week). Among the 924 participants, 7.4% did not meet minimum recommendations for physical activity, 57.3% had moderate activity levels, and 35.4% had high activity levels. Participants spent most of their time on occupational activities (median: 869METmin/week, IQR: 228-1953METmin/week). Female sex (odds ratio [OR]:0.40, 95% confidence interval [CI]:0.29-0.55), age≥51 years (OR: 0.45, 95%CI: 0.27-0.75), and family history of chronic disease (OR: 0.67, 95%CI: 0.48-0.94) were associated with significantly lower odds of a high activity level. Most civil servants in Xi'an, China, have moderate activity levels. Some have high activity levels, but few engage in vigorous-intensity physical activity. Interventions to encourage a high level of physical activity are needed, especially for women, older civil servants, and those with family histories of chronic disease. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Lewinsohn, E; Ziv-Raz, I; Dudai, N; Tadmor, Y; Lastochkin, E; Larkov, O; Chaimovitsh, D; Ravid, U; Putievsky, E; Pichersky, E; Shoham, Y
2000-12-07
Sweet basil (Ocimum basilicum L., Lamiaceae) is a common herb, used for culinary and medicinal purposes. The essential oils of different sweet basil chemotypes contain various proportions of the allyl phenol derivatives estragole (methyl chavicol), eugenol, and methyl eugenol, as well as the monoterpene alcohol linalool. To monitor the developmental regulation of estragole biosynthesis in sweet basil, an enzymatic assay for S-adenosyl-L-methionine (SAM):chavicol O-methyltransferase activity was developed. Young leaves display high levels of chavicol O-methyltransferase activity, but the activity was negligible in older leaves, indicating that the O-methylation of chavicol primarily occurs early during leaf development. The O-methyltransferase activities detected in different sweet basil genotypes differed in their substrate specificities towards the methyl acceptor substrate. In the high-estragole-containing chemotype R3, the O-methyltransferase activity was highly specific for chavicol, while eugenol was virtually not O-methylated. In contrast, chemotype 147/97, that contains equal levels of estragole and methyl eugenol, displayed O-methyltransferase activities that accepted both chavicol and eugenol as substrates, generating estragole and methyl eugenol, respectively. Chemotype SW that contains high levels of eugenol, but lacks both estragole and methyl eugenol, had apparently no allylphenol dependent O-methyltransferase activities. These results indicate the presence of at least two types of allylphenol-specific O-methyltransferase activities in sweet basil chemotypes, one highly specific for chavicol; and a different one that can accept eugenol as a substrate. The relative availability and substrate specificities of these O-methyltransferase activities biochemically rationalizes the variation in the composition of the essential oils of these chemotypes.
NASA Astrophysics Data System (ADS)
Ahn, Sul-Ah; Jung, Youngim
2016-10-01
The research activities of the computational physicists utilizing high performance computing are analyzed by bibliometirc approaches. This study aims at providing the computational physicists utilizing high-performance computing and policy planners with useful bibliometric results for an assessment of research activities. In order to achieve this purpose, we carried out a co-authorship network analysis of journal articles to assess the research activities of researchers for high-performance computational physics as a case study. For this study, we used journal articles of the Scopus database from Elsevier covering the time period of 2004-2013. We extracted the author rank in the physics field utilizing high-performance computing by the number of papers published during ten years from 2004. Finally, we drew the co-authorship network for 45 top-authors and their coauthors, and described some features of the co-authorship network in relation to the author rank. Suggestions for further studies are discussed.
Delta-configurations - Flare activity and magnetic-field structure
NASA Technical Reports Server (NTRS)
Patty, S. R.; Hagyard, M. J.
1986-01-01
Complex sunspots in four active regions of April and May 1980, all exhibiting regions of magnetic classification delta, were studied using data from the NASA Marshall Space Flight Center vector magnetograph. The vector magnetic field structure in the vicinity of each delta was determined, and the location of the deltas in each active region was correlated with the locations and types of flare activity for the regions. Two types of delta-configuration were found to exist, active and inactive, as defined by the relationships between magnetic field structure and activity. The active delta exhibited high flare activity, strong horizontal gradients of the longitudinal (line-of-sight) magnetic field component, a strong transverse (perpendicular to line-of-sight) component, and a highly nonpotential orientation of the photospheric magnetic field, all indications of a highly sheared magnetic field. The inactive delta, on the other hand, exhibited little or no flare production, weaker horizontal gradients of the longitudinal component, weaker transverse components, and a nearly potential, nonsheared orientation of the magnetic field. It is concluded that the presence of such sheared fields is the primary signature by which the active delta may be distinguished, and that it is this shear which produces the flare activity of the active delta.
Lu, Yi; Wu, Qing; Liu, Long-Zhu; Yu, Xiao-Jiang; Liu, Jin-Jun; Li, Man-Xiang; Zang, Wei-Jin
2018-04-01
Obesity, a major contributor to the development of cardiovascular diseases, is associated with an autonomic imbalance characterized by sympathetic hyperactivity and diminished vagal activity. Vagal activation plays important roles in weight loss and improvement of cardiac function. Pyridostigmine is a reversible acetylcholinesterase inhibitor, but whether it ameliorates cardiac lipid accumulation and cardiac remodeling in rats fed a high-fat diet has not been determined. This study investigated the effects of pyridostigmine on high-fat diet-induced cardiac dysfunction and explored the potential mechanisms. Rats were fed a normal or high-fat diet and treated with pyridostigmine. Vagal discharge was evaluated using the BL-420S system, and cardiac function by echocardiograms. Lipid deposition and cardiac remodeling were determined histologically. Lipid utility was assessed by qPCR. A high-fat diet led to a significant reduction in vagal discharge and lipid utility and a marked increase in lipid accumulation, cardiac remodeling, and cardiac dysfunction. Pyridostigmine improved vagal activity and lipid metabolism disorder and cardiac remodeling, accompanied by an improvement of cardiac function in high-fat diet-fed rats. An increase in the browning of white adipose tissue in pyridostigmine-treated rats was also observed and linked to the expression of UCP-1 and CIDEA. Additionally, pyridostigmine facilitated activation of brown adipose tissue via activation of the SIRT-1/AMPK/PGC-1α pathway. In conclusion, a high-fat diet resulted in cardiac lipid accumulation, cardiac remodeling, and a significant decrease in vagal discharge. Pyridostigmine ameliorated cardiomyopathy, an effect related to reduced cardiac lipid accumulation, and facilitated the browning of white adipose tissue while activating brown adipose tissue. Copyright © 2018 Elsevier B.V. All rights reserved.
Suzuki, Hidenobu; Gen, Keishi
2012-03-01
Blonanserin is a second-generation antipsychotic that was developed in Japan. We investigated the relationships between plasma concentration, the plasma anti-5-HT(2A) activity/anti-D₂ activity (S/D) ratio and extrapyramidal symptoms (EPS) in blonanserin dosing. The subjects were 29 outpatients with schizophrenia. We assessed EPS using the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). The plasma concentrations were measured by high performance liquid chromatography, and the plasma anti-D₂ and anti-5-HT(2A) activities were measured by [³H]-spiperone and [³H]-ketanserin radioreceptor assays. The results revealed that there were significant correlations between both the plasma concentration and the DIEPSS total score (P<0.05). A negative correlative tendency was found between the S/D ratio and the DIEPSS total score. Furthermore, the plasma concentrations were divided into a low plasma concentration group and a high plasma concentration group, and the S/D ratios were divided into a low S/D ratio group and a high S/D ratio group. We then compared each group based on the DIEPSS total scores. The score in the high plasma concentration-low S/D ratio group was significantly higher than in the high plasma concentration-high S/D ratio, low plasma concentration-high S/D ratio and low plasma concentration-low S/D ratio groups (P<0.05 for all). These findings indicate that the incidence of EPS during treatment with blonanserin is mainly determined by plasma concentration, but the incidence of EPS may be inhibited when anti-5HT(2A) activity is predominant over anti-D₂ activity. © 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology.
Huang, Yan; Zhu, Zengyan; Xie, Meilin; Xue, Jie
2015-09-01
A high-fat diet may result in changes in hepatic clock gene expression, but potential mechanisms are not yet elucidated. Adenosine monophosphate-activated protein kinase (AMPK) is a serine/threonine protein kinase that is recognized as a key regulator of energy metabolism and certain clock genes. Therefore, we hypothesized that AMPK may be involved in the alteration of hepatic clock gene expression under a high-fat environment. This study aimed to examine the effects of timed high-fat evening diet on the activity of hepatic AMPK, clock genes, and lipogenic genes. Mice with hyperlipidemic fatty livers were induced by orally administering high-fat milk via gavage every evening (19:00-20:00) for 6 weeks. Results showed that timed high-fat diet in the evening not only decreased the hepatic AMPK protein expression and activity but also disturbed its circadian rhythm. Accordingly, the hepatic clock genes, including clock, brain-muscle-Arnt-like 1, cryptochrome 2, and period 2, exhibited prominent changes in their expression rhythms and/or amplitudes. The diurnal rhythms of the messenger RNA expression of peroxisome proliferator-activated receptorα, acetyl-CoA carboxylase 1α, and carnitine palmitoyltransferase 1 were also disrupted; the amplitude of peroxisome proliferator-activated receptorγcoactivator 1α was significantly decreased at 3 time points, and fatty liver was observed. These findings demonstrate that timed high-fat diet at night can change hepatic AMPK protein levels, activity, and circadian rhythm, which may subsequently alter the circadian expression of several hepatic clock genes and finally result in the disorder of hepatic lipogenic gene expression and the formation of fatty liver. Copyright © 2015 Elsevier Inc. All rights reserved.
High-pressure tolerance of earthworm fibrinolytic and digestive enzymes.
Akazawa, Shin-Ichi; Tokuyama, Haruka; Sato, Shunsuke; Watanabe, Toshinori; Shida, Yosuke; Ogasawara, Wataru
2018-02-01
Earthworms contain several digestive and therapeutic enzymes that are beneficial to our health and useful for biomass utilization. Specifically, earthworms contain potent fibrinolytic enzymes called lumbrokinases, which are highly stable even at room temperature and remain active in dried earthworm powder. However, the high-temperature sterilization method leads to the inactivation of enzymes. Therefore, we investigated the effect of high-pressure treatment (HPT) (from 0.1 MPa to 500 MPa at 25°C and 50°C) on the enzymatic activity of lumbrokinase (LK), α-amylase (AMY), endoglucanase (EG), β-glucosidase (BGL), and lipase (LP) of the earthworm Eisenia fetida, Waki strain, and its sterilization ability in producing dietary supplement. LK showed thermo- and high-pressure tolerance. In addition, HPT may have resulted in pressure-induced stabilization and activation of LK. Although AMY activity was maintained up to 400 MPa at 25°C, the apparent activity decreased slightly at 50°C with HPT. EG showed almost the same pattern as AMY. However, it is possible that the effects of temperature and pressure compensated each other under 100 MPa at 50°C. BGL was shown to be a pressure- and temperature-sensitive enzyme, and LP showed a thermo- and high-pressure tolerance. The slight decrease in apparent activity occurred under 200 MPa at both temperatures. Furthermore, the low-temperature and pressure treatment completely sterilized the samples. These results provide a basis for the development of a novel earthworm dietary supplement with fibrinolytic and digestive activity and of high-pressure-tolerant enzymes to be used for biomass pretreatment. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Vermeij, Anouk; van Beek, Arenda H E A; Reijs, Babette L R; Claassen, Jurgen A H R; Kessels, Roy P C
2014-01-01
Older adults show more bilateral prefrontal activation during cognitive performance than younger adults, who typically show unilateral activation. This over-recruitment has been interpreted as compensation for declining structure and function of the brain. Here we examined how the relationship between behavioral performance and prefrontal activation is modulated by different levels of working-memory load. Eighteen healthy older adults (70.8 ± 5.0 years; MMSE 29.3 ± 0.9) performed a spatial working-memory task (n-back). Oxygenated ([O2Hb]) and deoxygenated ([HHb]) hemoglobin concentration changes were registered by two functional Near-Infrared Spectroscopy (fNIRS) channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition. [O2Hb] increased with rising working-memory load in both fNIRS channels. Based on the performance in the high working-memory load condition, the group was divided into low and high performers. A significant interaction effect of performance level and hemisphere on [O2Hb] increase was found, indicating that high performers were better able to keep the right prefrontal cortex engaged under high cognitive demand. Furthermore, in the low performers group, individuals with a larger decline in task performance from the control to the high working-memory load condition had a larger bilateral increase of [O2Hb]. The high performers did not show a correlation between performance decline and working-memory load related prefrontal activation changes. Thus, additional bilateral prefrontal activation in low performers did not necessarily result in better cognitive performance. Our study showed that bilateral prefrontal activation may not always be successfully compensatory. Individual behavioral performance should be taken into account to be able to distinguish successful and unsuccessful compensation or declined neural efficiency.
Tsai, Hsiao-Ya; Lin, Chih-Pei; Huang, Po-Hsun; Li, Szu-Yuan; Chen, Jia-Shiong; Lin, Feng-Yen; Chen, Jaw-Wen; Lin, Shing-Jong
2016-01-01
Coenzyme Q10 (CoQ10), an antiapoptosis enzyme, is stored in the mitochondria of cells. We investigated whether CoQ10 can attenuate high glucose-induced endothelial progenitor cell (EPC) apoptosis and clarified its mechanism. EPCs were incubated with normal glucose (5 mM) or high glucose (25 mM) enviroment for 3 days, followed by treatment with CoQ10 (10 μM) for 24 hr. Cell proliferation, nitric oxide (NO) production, and JC-1 assay were examined. The specific signal pathways of AMP-activated protein kinase (AMPK), eNOS/Akt, and heme oxygenase-1 (HO-1) were also assessed. High glucose reduced EPC functional activities, including proliferation and migration. Additionally, Akt/eNOS activity and NO production were downregulated in high glucose-stimulated EPCs. Administration of CoQ10 ameliorated high glucose-induced EPC apoptosis, including downregulation of caspase 3, upregulation of Bcl-2, and increase in mitochondrial membrane potential. Furthermore, treatment with CoQ10 reduced reactive oxygen species, enhanced eNOS/Akt activity, and increased HO-1 expression in high glucose-treated EPCs. These effects were negated by administration of AMPK inhibitor. Transplantation of CoQ10-treated EPCs under high glucose conditions into ischemic hindlimbs improved blood flow recovery. CoQ10 reduced high glucose-induced EPC apoptosis and dysfunction through upregulation of eNOS, HO-1 through the AMPK pathway. Our findings provide a potential treatment strategy targeting dysfunctional EPC in diabetic patients. PMID:26682233
Dai, Jiezhi; Zhang, Xiaotian; Li, Li; Chen, Hua; Chai, Yimin
2017-01-01
Type 2 diabetes is a persistent inflammatory response that impairs the healing process. We hypothesized that stimulation with high glucose following a pro-inflammatory signal would lead to autophagy inhibition, reactive oxygen species (ROS) production and eventually to the activation of the Nod-like receptor protein (NLRP) -3. Macrophages were isolated from human diabetic wound. We measured the expression of NLRP3, caspase1 and interleukin-1 beta (IL-1β) by western blot and real-time PCR, and the surface markers on cells by flow cytometry. THP-1-derived macrophages exposed to high glucose were applied to study the link between autophagy, ROS and NLRP3 activation. LC3-II, P62, NLRP3 inflammation and IL-1β expression were measured by western blot and real-time PCR. ROS production was measured with a Cellular Reactive Oxygen Species Detection Assay Kit. Macrophages isolated from diabetic wounds exhibited a pro-inflammatory phenotype, including sustained NLRP3 inflammasome activity associated with IL-1β secretion. Our data showed that high glucose inhibited autophagy, induced ROS production, and activated NLRP3 inflammasome and cytokine secretion in THP-1-derived macrophages. To study high glucose-induced NLRP3 inflammasome signalling, we performed studies using an autophagy inducer, a ROS inhibitor and a NLRP3 inhibitor and found that all reduced the NLRP3 inflammasome activation and cytokine secretion. Sustained NLRP3 inflammasome activity in wound-derived macrophages contributes to the hyper-inflammation in human diabetic wounds. Autophagy inhibition and ROS generation play an essential role in high glucose-induced NLRP3 inflammasome activation and cytokine secretion in macrophages. © 2017 The Author(s). Published by S. Karger AG, Basel.
Nutrition Assessment of B-Vitamins in Highly Active and Sedentary Women.
Woolf, Kathleen; Hahn, Nicole L; Christensen, Megan M; Carlson-Phillips, Amanda; Hansen, Christine M
2017-03-26
Female athletes and active women require adequate nutrition for optimal health and performance. Nutrition assessments are needed to identify potential nutrients of concern. Folate, vitamin B6, and vitamin B12 function in important pathways used during physical activity and female athletes may be at risk for poor status of these micronutrients. This cross-sectional study described a comprehensive nutrition assessment of the B-vitamins (folate, vitamin B6, and vitamin B12) using both dietary (food and dietary supplements) and biochemical assessments among highly active and sedentary women. Highly active ( n = 29; age 20 ± 2 years; body mass index (BMI) 23.8 ± 3.5 kg/m²) and sedentary ( n = 29; age 24 ± 3 years; BMI 22.6 ± 3.0 kg/m²) women were recruited for this study. Participants completed 7-day weighed food records and a fasting blood draw. Although the highly active women reported higher intakes of energy ( p < 0.01), folate ( p < 0.01), vitamin B6 ( p < 0.01), and vitamin B12 ( p < 0.01), no significant differences were found between the groups for biomarkers of folate, vitamin B6, and vitamin B12. All of the highly active women had biomarkers within the desired reference ranges, suggesting good status. In general, most participants were able to meet the 1998 Recommended Daily Allowance (RDA) from food alone. For the women that reported using dietary supplements, micronutrient intakes met the 1998 RDA and in some cases, exceeded the Tolerable Upper Intake Level. This nutrition assessment documented good status for folate, vitamin B6, and vitamin B12 in the highly active women. Similar assessment approaches (food, dietary supplements, and biomarkers) should to completed with other nutrients of concern for the female athlete.
Alricsson, Marie; Domalewski, Debra; Romild, Ulla; Asplund, Ragnar
2008-01-01
Adolescents in the industrial world are becoming less physically active and are increasingly adopting a sedentary life-style in front of computers and television screens. to determine self-related health, physical activity, sleeping habits, prevalence of overweight, and body complaints in Australian senior high school students. Participants were 466 high school students aged 15-17 years enrolled in academic and vocational programs. A questionnaire was completed at two senior high schools with questions about weight and height, health, physical activity, type of physical activity/sport, intensity, sleeping habits, and possible injuries or complaints during the last three months. Seventy seven percent of the high school students participated in sports on a regular basis. Compared with vocational programs, more males and females in academic programs participated in sports (71% and 80% respectively) (p = .036). Males reported significantly better health than females (p < .0001). 65% of the study group reported body complaints during the last 3 months. A higher number of females than males reported complaints about the back (p = .007) and the hip (p = .05). Good sleep was reported in 82.1% of males and in 76.6% of females. In males, 44.3% were often sleepy in the daytime (females 56.6%, p < .01). Underweight, physical activity and good sleep are factors with significant positive effect on good health, whereas overweight is a negative factor. Proper sleep habits and higher physical activity levels should be promoted among high school students, and TV viewing time and video game use restricted. Additionally, schools should provide opportunities for young people to participate in a wider range of physical activities that address their individual needs while promoting the health benefits of engaging in regular exercise.
Nutrition Assessment of B-Vitamins in Highly Active and Sedentary Women
Woolf, Kathleen; Hahn, Nicole L.; Christensen, Megan M.; Carlson-Phillips, Amanda; Hansen, Christine M.
2017-01-01
Background: Female athletes and active women require adequate nutrition for optimal health and performance. Nutrition assessments are needed to identify potential nutrients of concern. Folate, vitamin B6, and vitamin B12 function in important pathways used during physical activity and female athletes may be at risk for poor status of these micronutrients. This cross-sectional study described a comprehensive nutrition assessment of the B-vitamins (folate, vitamin B6, and vitamin B12) using both dietary (food and dietary supplements) and biochemical assessments among highly active and sedentary women. Methods: Highly active (n = 29; age 20 ± 2 years; body mass index (BMI) 23.8 ± 3.5 kg/m2) and sedentary (n = 29; age 24 ± 3 years; BMI 22.6 ± 3.0 kg/m2) women were recruited for this study. Participants completed 7-day weighed food records and a fasting blood draw. Results: Although the highly active women reported higher intakes of energy (p < 0.01), folate (p < 0.01), vitamin B6 (p < 0.01), and vitamin B12 (p < 0.01), no significant differences were found between the groups for biomarkers of folate, vitamin B6, and vitamin B12. All of the highly active women had biomarkers within the desired reference ranges, suggesting good status. In general, most participants were able to meet the 1998 Recommended Daily Allowance (RDA) from food alone. For the women that reported using dietary supplements, micronutrient intakes met the 1998 RDA and in some cases, exceeded the Tolerable Upper Intake Level. Conclusion: This nutrition assessment documented good status for folate, vitamin B6, and vitamin B12 in the highly active women. Similar assessment approaches (food, dietary supplements, and biomarkers) should to completed with other nutrients of concern for the female athlete. PMID:28346362
Kur'yanova, E V; Teplyi, D L; Zhukova, Yu D; Zhukovina, N V
2015-12-01
The basic behavioral activity of nonlinear rats was evaluated from the sum of crossed peripheral and central squares and peripheral and central rearing postures in the open fi eld test. This index was low (<20 episodes), intermediate (20-29 episodes), or high (>30 episodes). Male rats with high score of orientation and exploratory activity were characterized by higher indexes of total heart rate variability than rats with low or intermediate activity. Specimens with a greater contribution of VLF waves into the total power spectrum of heart rate variability were shown to dominate among the rats with high behavioral activity. Our results are consistent with the notions of a suprasegmental nature of VLF waves.
Geologic fracturing method and resulting fractured geologic structure
Mace, Jonathan L.; Bradley, Christopher R.; Greening, Doran R.; Steedman, David W.
2016-11-08
Detonation control modules and detonation control circuits are provided herein. A trigger input signal can cause a detonation control module to trigger a detonator. A detonation control module can include a timing circuit, a light-producing diode such as a laser diode, an optically triggered diode, and a high-voltage capacitor. The trigger input signal can activate the timing circuit. The timing circuit can control activation of the light-producing diode. Activation of the light-producing diode illuminates and activates the optically triggered diode. The optically triggered diode can be coupled between the high-voltage capacitor and the detonator. Activation of the optically triggered diode causes a power pulse to be released from the high-voltage capacitor that triggers the detonator.
The effects of diet and physical activity on plasma homovanillic acid in normal human subjects.
Kendler, K S; Mohs, R C; Davis, K L
1983-03-01
This study examines the effect of diet and moderate physical activity on plasma levels of the dopamine metabolite homovanillic acid (HVA) in healthy young males. At weekly intervals, subjects were fed four isocaloric meals: polycose (pure carbohydrate), sustecal, low monoamine, and high monoamine. Moderate physical activity consisted of 30 minutes of exercise on a bicycle ergometer. The effect of diet on plasma HVA (pHVA) was highly significant. Compared to the polycose meal, the high monoamine meal significantly increased pHVA. Moderate physical activity also significantly increased pHVA. Future clinical studies using pHVA in man as an index of brain dopamine function should control for the effects of both diet and physical activity.
Lövström, Ludvig; Emtner, Margareta; Alving, Kjell; Nordvall, Lennart; Borres, Magnus P; Janson, Christer; Malinovschi, Andrei
2016-01-01
Earlier studies on the levels of physical activity in asthma patients compared with controls have yielded varying results. We have previously reported that high versus moderate levels of physical activity were associated with higher prevalence of wheezing, especially in females. Here we studied the levels of physical activity in young patients with asthma and healthy subjects and their effect on asthma control. Four hundred eight physician-diagnosed patients with asthma and 118 controls (10-34 years) answered questions concerning frequency and/or duration of physical activity and undertook the Asthma Control Test (ACT), spirometry, methacholine challenges and exhaled nitric oxide measurements. Asthma patients were more frequently physically active (P = 0.01) and for longer durations (P = 0.002) than controls. Highly versus moderately physically active patients with asthma had a higher prevalence of not well-controlled asthma (ACT < 20) when physical activity was assessed by frequency (40.6% vs 24.1%, P = 0.001) or duration (39.0% vs 21.7%, P < 0.001). This was only seen in females who had reduced ACT items (P < 0.05). Frequently versus moderately active females had an odds ratio of 4.81 (2.43, 9.51) to have ACT < 20, while no such effect was found in males (OR 1.18 (0.61, 2.30)) and this interaction was statistically significantly associated with gender (P = 0.003). No differences in fraction of exhaled nitric oxide or methacholine reactivity were found between moderately and highly physically active females with asthma. Young asthma patients were more active than controls. High levels of physical activity were associated with poor asthma control as judged by the ACT in females, but not in males, and this appears unrelated to airway inflammation or responsiveness. © 2015 Asian Pacific Society of Respirology.
2014-01-01
From a virtual screening starting point, inhibitors of the serum and glucocorticoid regulated kinase 1 were developed through a combination of classical medicinal chemistry and library approaches. This resulted in highly active small molecules with nanomolar activity and a good overall in vitro and ADME profile. Furthermore, the compounds exhibited unusually high kinase and off-target selectivity due to their rigid structure. PMID:25589934
Halland, Nis; Schmidt, Friedemann; Weiss, Tilo; Saas, Joachim; Li, Ziyu; Czech, Jörg; Dreyer, Matthias; Hofmeister, Armin; Mertsch, Katharina; Dietz, Uwe; Strübing, Carsten; Nazare, Marc
2015-01-08
From a virtual screening starting point, inhibitors of the serum and glucocorticoid regulated kinase 1 were developed through a combination of classical medicinal chemistry and library approaches. This resulted in highly active small molecules with nanomolar activity and a good overall in vitro and ADME profile. Furthermore, the compounds exhibited unusually high kinase and off-target selectivity due to their rigid structure.
Anti-collagenase, anti-elastase and anti-oxidant activities of extracts from 21 plants
Thring, Tamsyn SA; Hili, Pauline; Naughton, Declan P
2009-01-01
Background Owing to their roles in tissue remodelling in health and disease, several studies have reported investigations on plant extracts as inhibitors of proteinases and as anti-oxidants. Methods The anti-ageing and anti-oxidant properties of 23 plant extracts (from 21 plant species) were assessed as anti-elastase and anti-collagenase activities and in selected anti-oxidant assays along with phenolic content. Results Anti-elastase activities were observed for nine of the extracts with inhibitory activity in the following order: white tea (~89%), cleavers (~58%), burdock root (~51%), bladderwrack (~50%), anise and angelica (~32%). Anti-collagenase activities were exhibited by sixteen plants of which the highest activity was seen in white tea (~87%), green tea (~47%), rose tincture (~41%), and lavender (~31%). Nine plant extracts had activities against both elastase (E) and collagenase (C) and were ranked in the order of white tea (E:89%, C:87%) > bladderwrack (E:50%, C:25%) > cleavers (E:58%, C:7%) > rose tincture (E:22%, C:41%) > green tea (E:10%: C:47%) > rose aqueous (E: 24%, C:26%) > angelica (E:32%, C:17%) > anise (E:32%, C:6%) > pomegranate (E:15%, C:11%). Total phenolic content varied between 0.05 and 0.26 mg gallic acid equivalents (GAE)/mL with the exception of white tea (0.77 mg GAE/mL). For anti-oxidant assessment, the Trolox equivalent anti-oxidant capacity (TEAC) assay revealed activity for all extracts. White tea had the highest activity equivalent to ~21 μM Trolox for a 6.25 μg aliquot. In addition, seven extracts exhibited activities = 10 μM Trolox with witch hazel (6.25 μg = 13 μM Trolox) and rose aqueous (6.25 μg = 10 μM Trolox) showing very high activities at low concentrations. A high activity for white tea was also found in the superoxide dismutase (SOD) assay in which it exhibited ~88% inhibition of reduction of nitroblue tetrazolium. High activities were also observed for green tea (86.41%), rose tincture (82.77%), witch hazel (82.05%) and rose aqueous (73.86%). Conclusion From a panel of twenty three plant extracts, some one dozen exhibit high or satisfactory anti-collagenase or anti-elastase activities, with nine having inhibitory activity against both enzymes. These included white tea which was found to have very high phenolic content, along with high TEAC and SOD activities. PMID:19653897
Study of pharmacological activities of methanol extract of Jatropha gossypifolia fruits.
Apu, Apurba Sarker; Hossain, Faruq; Rizwan, Farhana; Bhuyan, Shakhawat Hossan; Matin, Maima; Jamaluddin, A T M
2012-12-01
The present study was carried out to investigate the possible in vivo analgesic, neuropharmacological and anti-diarrheal activities of the methanol extract of Jatropha gossypifolia fruits. The analgesic activity was measured by acetic acid induced writhing inhibition test. The neuropharmacological activities were evaluated by hole cross, hole-board, and elevated plus-maze (EPM) tests and the anti-diarrheal activity was assessed by castor oil induced diarrhea inhibition method. The extract showed highly significant (P < 0.001) analgesic activity with % inhibitions of writhing response at doses 200 and 400 mg/kg body weight were 77.86% and 71.25%, respectively. The extract at both doses showed significant (P < 0.05) sedative effect in-hole cross test. In-hole board test, the extract showed highly significant (P < 0.001) anxiolytic activity at lower dose whereas this activity was observed at higher dose in EPM test. The extract also showed highly significant (P < 0.001) anti-diarrheal activity. The findings of the study clearly indicate the presence of significant analgesic, neuropharmacological and anti-diarrheal properties of the plant, which demands further investigation including, compound isolation.
NASA Astrophysics Data System (ADS)
Li, Shuo; Zhang, Guangshan; Zheng, Heshan; Zheng, Yongjie; Wang, Peng
2018-05-01
In this study, BiFeO3 (BFO) powders decorated on nickel foam (NF) with a high catalytic activity are prepared via a one-step microwave-assisted hydrothermal method. The factors that influence the degradation of bisphenol A (BPA) with BFO/NFs as catalysts are optimized to improve the catalytic activity in a microwave-enhanced Fenton-like process. BFO/NF exhibit a superior catalytic activity with a high BPA removal ratio (98.4%) and TOC removal ratio (69.5%) within 5 min. Results indicate that NF significantly affect the improvement of the catalytic activity of BFO because it served as a source of hydroxyl radicals (•OH) during degradation. The amount of •OH generated by BFO/NF is approximately 1.65-fold higher than that by pure BFO. After six reaction cycles, the stability and reusability of •OH remain high. These findings provide new insights into the synthesis of composites on heterogeneous catalysts with high efficiency and easy recyclability for water treatment applications.
Oresic Bender, Kristina; Ofori, Leslie; van der Linden, Wouter A; Mock, Elliot D; Datta, Gopal K; Chowdhury, Somenath; Li, Hao; Segal, Ehud; Sanchez Lopez, Mateo; Ellman, Jonathan A; Figdor, Carl G; Bogyo, Matthew; Verdoes, Martijn
2015-04-15
The cysteine cathepsins are a group of 11 proteases whose function was originally believed to be the degradation of endocytosed material with a high degree of redundancy. However, it has become clear that these enzymes are also important regulators of both health and disease. Thus, selective tools that can discriminate between members of this highly related class of enzymes will be critical to further delineate the unique biological functions of individual cathepsins. Here we present the design and synthesis of a near-infrared quenched activity-based probe (qABP) that selectively targets cathepsin S which is highly expressed in immune cells. Importantly, this high degree of selectivity is retained both in vitro and in vivo. In combination with a new green-fluorescent pan-reactive cysteine cathepsin qABP we performed dual color labeling studies in bone marrow-derived immune cells and identified vesicles containing exclusively cathepsin S activity. This observation demonstrates the value of our complementary cathepsin probes and provides evidence for the existence of specific localization of cathepsin S activity in dendritic cells.
Bismuth Oxysulfide and Its Polymer Nanocomposites for Efficient Purification
Luo, Yidong; Qiao, Lina; Wang, Huanchun; Lan, Shun; Shen, Yang; Lin, Yuanhua; Nan, Cewen
2018-01-01
The danger of toxic organic pollutants in both aquatic and air environments calls for high-efficiency purification material. Herein, layered bismuth copper oxychalcogenides, BiCuSO, nanosheets of high photocatalytic activity were introduced to the PVDF (Polyvinylidene Fluoride). The fibrous membranes provide an easy, efficient, and recyclable way to purify organic pollutant. The physical and photophysical properties of the BiCuSO and its polymer composite were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible diffuse reflection spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), electron spin resonance (EPR). Photocatalysis of Congo Red reveals that the BiCuSO/PVDF shows a superior photocatalytic activity of a 55% degradation rate in 70 min at visible light. The high photocatalytic activity is attributed to the exposed active {101} facets and the triple vacant associates VBi‴VO••VBi‴. By engineering the intrinsic defects on the surface of bismuth oxysulfide, high solar-driven photocatalytic activity can be approached. The successful fabrication of the bismuth oxysulfide and its polymer nanocomposites provides an easy and general approach for high-performance purification materials for various applications. PMID:29562701
Effects of aging on value-directed modulation of semantic network activity during verbal learning
Cohen, Michael S.; Rissman, Jesse; Suthana, Nanthia A.; Castel, Alan D.; Knowlton, Barbara J.
2015-01-01
While impairments in memory recall are apparent in aging, older adults show a remarkably preserved ability to selectively remember information deemed valuable. Here, we use fMRI to compare brain activation in healthy older and younger adults during encoding of high and low value words to determine whether there are differences in how older adults achieve value-directed memory selectivity. We find that memory selectivity in older adults is associated with value-related changes in activation during word presentation in left hemisphere regions that are involved in semantic processing, similar to young adults. However, highly selective young adults show a relatively greater increase in semantic network activity during encoding of high-value items, whereas highly selective older adults show relatively diminished activity during encoding of low-value items. Additionally, only younger adults showed value-related increases in activity in semantic and reward processing regions during presentation of the value cue preceding each to-be-remembered word. Young adults therefore respond to cue value more proactively than do older adults, yet the magnitude of value-related differences in cue period brain activity did not predict individual differences in memory selectivity. Thus, our data also show that age-related reductions in prestimulus activity do not always lead to inefficient performance. PMID:26244278
THE PREPARATION AND PROPERTIES OF HIGHLY PURIFIED ASCORBIC ACID OXIDASE
Powers, Wendell H.; Lewis, Stanley; Dawson, Charles R.
1944-01-01
1. A method is described for the preparation of a highly purified ascorbic acid oxidase containing 0.24 per cent copper. 2. Using comparable activity measurements, this oxidase is about one and a half times as active on a dry weight basis as the hitherto most highly purified preparation described by Lovett-Janison and Nelson. The latter contained 0.15 per cent copper. 3. The oxidase activity is proportional to the copper content and the proportionality factor is the same as that reported by Lovett-Janison and Nelson. 4. When dialyzed free of salt, the blue concentrated oxidase solutions precipitate a dark green-blue protein which carries the activity. This may be prevented by keeping the concentrated solutions about 0.1 M in Na2HPO4. 5. When highly diluted for activity measurements the oxidase rapidly loses activity (irreversibly) previous to the measurement, unless the dilution is made with a dilute inert protein (gelatin) solution. Therefore activity values obtained using such gelatin-stabilized dilute solutions of the oxidase run considerably higher than values obtained by the Lovett-Janison and Nelson technique. 6. The effect of pH and substrate concentration on the activity of the purified oxidase in the presence and absence of inert protein was studied. PMID:19873382
Academic stress and active learning of nursing students: A cross-sectional study.
Magnavita, Nicola; Chiorri, Carlo
2018-06-08
The active role of nursing students is particularly important in the delivery of health care, since playing an active role at the bedside and the use of active and collaborative engagement of students in the nursing activities has been associated with improved student learning. This is consistent with Karasek's learning hypothesis, but it has never been tested on nursing students. This study aimed at investigating whether nursing students in high control conditions reported lower levels of work impairment than students in the conditions with low control, compared them with a group of healthcare workers (HCWs), and tested the moderating role of social support at work. 633 nursing students and 160 HCWs completed the Nursing Work Functioning Questionnaire (NWFQ), and the Demand-Control-Support questionnaire (DCS). Results showed that nursing students reported higher levels of work impairment and were less likely to be classified as active (high demand/high control) or low strain (low demand/high control) than HCWs, and that social support at work moderated the association between being in active or low strain condition and work impairment. Programs to enhance the learning of nursing students must not only fight strain and isolation but must also promote active learning, by increasing the control over the job, team work, and support from teachers. Copyright © 2018. Published by Elsevier Ltd.
Shieh, Kun-Ruey; Yang, Shu-Chuan
2018-03-27
The native Formosan wood mouse (Apodemus semotus) is the dominant rodent in Taiwan. In their natural environment, Formosan wood mice exhibit high locomotor activity, including searching and exploratory behaviours, which is observed similarly in the laboratory environment. How the behavioural responses of Formosan wood mice exhibit in elevated plus maze and marble burying tests remains unclear. How corticosterone levels and central dopaminergic activities are related to the behaviours in these tests is also unclear. This study compared the behaviours of Formosan wood mice with that of C57BL/6J mice using the elevated plus maze and marble burying tests, and measured the corticosterone levels and central dopaminergic activities. Formosan wood mice showed greater locomotor and exploratory activity than the C57BL/6J mice. Similarly, the marble burying and rearing numbers were higher for Formosan wood mice. High locomotor and exploratory behaviours were strongly correlated with corticosterone levels after acute mild restraint stress in Formosan wood mice. The anxiolytic, diazepam, reduced the high exploratory activity, corticosterone levels and central dopaminergic activities. The high locomotor and exploratory behaviours of Formosan wood mice are related to the corticosterone levels and central dopaminergic activities. These data may explain Formosan wood mice dominance in the intermediate altitude of Taiwan.
Seasonal Variation of High-latitude Geomagnetic Activity Revisited
NASA Astrophysics Data System (ADS)
Tanskanen, E.; Hynönen, R.; Mursula, K.
2017-12-01
The coupling of the solar wind and auroral region has been examined by using westward electrojet indices since 1966 - 2014. We have studied the seasonal variation of high-latitude geomagnetic activity in individual years for solar cycles 20 - 24. The classical two-equinox activity pattern in geomagnetic activity was seen in multi-year averages but it was found in less than one third of the years examined. We found that the seasonal variation of high-latitude geomagnetic activity closely follows the solar wind speed. While the mechanisms leading to the two-equinox maxima pattern are in operation, the long-term change of solar wind speed tends to mask the effect of these mechanisms for individual years. We identified the most active and the second most active season based on westward electrojet indices AL (1966 - 2014) and IL (1995 - 2014). The annual maximum is found at either equinox in 2/3 and at either solstice in 1/3 of the years examined. Large cycle-to-cycle variation is found in the seasonal pattern: equinox maxima are more common during cycles 21 and 22 than in cycles 23 or 24. An exceptionally long winter dominance in high-latitude activity and solar wind speed is seen in the declining phase of cycle 23, after the appearance of the long-lasting low-latitude coronal hole.
Upper Limb Muscle and Brain Activity in Light Assembly Task on Different Load Levels
NASA Astrophysics Data System (ADS)
Zadry, Hilma Raimona; Dawal, Siti Zawiah Md.; Taha, Zahari
2010-10-01
A study was conducted to investigate the effect of load on upper limb muscles and brain activities in light assembly task. The task was conducted at two levels of load (Low and high). Surface electromyography (EMG) was used to measure upper limb muscle activities of twenty subjects. Electroencephalography (EEG) was simultaneously recorded with EMG to record brain activities from Fz, Pz, O1 and O2 channels. The EMG Mean Power Frequency (MPF) of the right brachioradialis and the left upper trapezius activities were higher on the high-load task compared to low-load task. The EMG MPF values also decrease as time increases, that reflects muscle fatigue. Mean power of the EEG alpha bands for the Fz-Pz channels were found to be higher on the high-load task compared to low-load task, while for the O1-O2 channels, they were higher on the low-load task than on the high-load task. These results indicated that the load levels effect the upper limb muscle and brain activities. The high-load task will increase muscle activities on the right brachioradialis and the left upper tapezius muscles, and will increase the awareness and motivation of the subjects. Whilst the low-load task can generate drowsiness earlier. It signified that the longer the time and the more heavy of the task, the subjects will be more fatigue physically and mentally.
Leisure-time physical activity in relation to occupational physical activity among women.
Ekenga, Christine C; Parks, Christine G; Wilson, Lauren E; Sandler, Dale P
2015-05-01
The objective of this study is to examine the association between occupational physical activity and leisure-time physical activity among US women in the Sister Study. We conducted a cross-sectional study of 26,334 women who had been employed in their current job for at least 1 year at baseline (2004-2009). Occupational physical activity was self-reported and leisure-time physical activity was estimated in metabolic equivalent hours per week. Log multinomial regression was used to evaluate associations between occupational (sitting, standing, manually active) and leisure-time (insufficient, moderate, high) activity. Models were adjusted for age, race/ethnicity, education, income, geographic region, and body mass index. Only 54% of women met or exceeded minimum recommended levels of leisure-time physical activity (moderate 32% and high 22%). Women who reported sitting (prevalence ratio (PR)=0.82, 95% confidence interval (CI): 0.74-0.92) or standing (PR=0.84, 95% CI: 0.75-0.94) most of the time at work were less likely to meet the requirements for high leisure-time physical activity than manually active workers. Associations were strongest among women living in the Northeast and the South. In this nationwide study, low occupational activity was associated with lower leisure-time physical activity. Women who are not active in the workplace may benefit from strategies to promote leisure-time physical activity. Published by Elsevier Inc.
Leisure-time physical activity in relation to occupational physical activity among women
Ekenga, Christine C.; Parks, Christine G.; Wilson, Lauren E.; Sandler, Dale P.
2017-01-01
Objective To examine the association between occupational physical activity and leisure-time physical activity among US women in the Sister Study. Methods We conducted a cross-sectional study of 26,334 women who had been employed in their current job for at least 1 year at baseline (2004–2009). Occupational physical activity was self-reported and leisure-time physical activity was estimated in metabolic equivalent hours per week. Log multinomial regression was used to evaluate associations between occupational (sitting, standing, manually active) and leisure-time (insufficient, moderate, high) activity. Models were adjusted for age, race/ethnicity, education, income, geographic region, and body mass index. Results Only 54% of women met or exceeded minimum recommended levels of leisure-time physical activity (moderate 32% and high 22%). Women who reported sitting (PR = 0.82, 95% CI: 0.74–0.92) or standing (PR = 0.84, 95% CI: 0.75–0.94) most of the time at work were less likely to meet the requirements for high leisure-time physical activity than manually active workers. Associations were strongest among women living in the Northeast and the South. Conclusion In this nationwide study, low occupational activity was associated with lower leisure-time physical activity. Women who are not active in the workplace may benefit from strategies to promote leisure-time physical activity. PMID:25773471
Bimodal activated carbons derived from resorcinol-formaldehyde cryogels
Szczurek, Andrzej; Amaral-Labat, Gisele; Fierro, Vanessa; Pizzi, Antonio; Celzard, Alain
2011-01-01
Resorcinol-formaldehyde cryogels prepared at different dilution ratios have been activated with phosphoric acid at 450 °C and compared with their carbonaceous counterparts obtained by pyrolysis at 900 °C. Whereas the latter were, as expected, highly mesoporous carbons, the former cryogels had very different pore textures. Highly diluted cryogels allowed preparation of microporous materials with high surface areas, but activation of initially dense cryogels led to almost non-porous carbons, with much lower surface areas than those obtained by pyrolysis. The optimal acid concentration for activation, corresponding to stoichiometry between molecules of acid and hydroxyl groups, was 2 M l−1, and the acid–cryogel contact time also had an optimal value. Such optimization allowed us to achieve surface areas and micropore volumes among the highest ever obtained by activation with H3PO4, close to 2200 m2 g−1 and 0.7 cm3 g−1, respectively. Activation of diluted cryogels with a lower acid concentration of 1.2 M l−1 led to authentic bimodal activated carbons, having a surface area as high as 1780 m2 g−1 and 0.6 cm3 g−1 of microporous volume easily accessible through a widely developed macroporosity. PMID:27877405
NASA Astrophysics Data System (ADS)
Ooi, M. D. Johan; Aziz, A. Abdul
2017-05-01
Surfactant removal from the surface of platinum nanoparticles prepared by solution based method is a prerequisite process to accomplish a high catalytic activity for electrochemical reactions. Here, we report a possible approach of combining acid acetic with thermal treatment for improving catalytic performance of formic acid oxidation. This strategy involves conversion of amine to amide in acetic acid followed by surfactant removal via subsequent thermal treatment at 85 °C. This combined activation technique produced monodisperse nanoparticle with the size of 3 to 5 nm with enhanced formic acid oxidation activity, particularly in perchloric acid solution. Pt treated in 1 h of acetic acid and heat treatment of 9 h shows high electrochemical surface area value (27.6 m2/g) compares to Pt without activation (16.6 m2/g). The treated samples also exhibit high current stability of 0.3 mA/cm2 compares to the as-prepared mA/cm2). Shorter duration of acid wash and longer duration of heating process result in high electrocatalytic activity. This work demonstrates a possible technique in improving catalytic activity of platinum nanoparticles synthesized using methylamine as surfactant.
Terefe, Netsanet Shiferaw; Delon, Antoine; Buckow, Roman; Versteeg, Cornelis
2015-12-01
Partially purified blueberry polyphenol oxidase (PPO) in Mcllvaine buffer (pH=3.6, typical pH of blueberry juice) was subjected to processing at isothermal-isobaric conditions at temperatures from 30 to 80 °C and pressure from 0.1 to 700 MPa. High pressure processing at 30-50 °C at all pressures studied caused irreversible PPO activity increase with a maximum of 6.1 fold increase at 500 MPa and 30 °C. Treatments at mild pressure-mild temperature conditions (0.1-400 MPa, 60 °C) also caused up to 3 fold PPO activity increase. Initial activity increase followed by a decrease occurred at relatively high pressure-mild temperature (400-600 MPa, 60 °C) and mild pressure-high temperature (0.1-400 MPa, 70-80 °C) combinations. At temperatures higher than 76 °C, monotonic decrease in PPO activity occurred at 0.1 MPa and pressures higher than 500 MPa. The activation/inactivation kinetics of the enzyme was successfully modelled assuming consecutive reactions in series with activation followed by inactivation. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
Bajunirwe, Francis; Bangsberg, David R; Sethi, Ajay K
2013-05-03
Antiretroviral treatment restores the physical and immunological function for patients with HIV/AIDS and the return of sexual desire. The frequency and correlates of sexual activity among patients receiving ART have not been widely studied. There is concern that widespread availability of ART may result in sexual disinhibition including practice of high-risk sexual behavior. We determined the correlates of sexual activity and high-risk sexual behavior in an ART-treated population in rural and urban Uganda. We conducted a cross-sectional study among 329 ART-treated adult patients at two hospitals, one located in rural and another in urban western Uganda. We collected data on sexual activity, frequency of condom use, pregnancy, viral load (VL) and CD4. Patients were considered sexually active if they had had sexual intercourse in the last 6 months. Any unprotected sex was considered high-risk sex. A two-stage logistic regression was performed to determine factors associated with sexual activity and high-risk sex among those sexually active. Overall, 222 (67%) patients were women, 138 (41.2%) had been on ART for at least one year, and 168 (51.4%) were sexually active of whom 127 (75.6%) used condoms at the last intercourse. Younger age (<=30 years) (Odds ratio; OR=2.3, 95% CI 1.2, 4.2), higher monthly income (OR=4.1, 95% CI 2.4, 7.4), and being married (OR=22.7, 95% CI 8.2, 62.9) were associated with being sexually active. Undetectable VL, CD4 count and treatment duration were not significantly associated with sexual activity. Among the sexually active, alcohol consumption (OR=3.3, 95% CI 1.2, 9.1) and unknown serostatus of partner (OR=5.8, 95% CI 1.5, 21.4) were significant predictors of high-risk sexual behavior. The frequency of unprotected sex at the last intercourse was 25.9% and 22.1% among the men and women respectively and was not significantly different (p value for chi square test =0.59). Younger persons receiving ART are more likely to be sexually active. ART clients are more likely to engage in unprotected sex when sero-status of partner is unknown or report use of alcohol. Counseling on alcohol use and disclosure of sero-status may be useful in reducing high risk sexual behavior.
Anderson, Sarah E; Economos, Christina D; Must, Aviva
2008-10-22
The high prevalence of childhood obesity underscores the importance of monitoring population trends in children's activity and screen time, and describing associations with child age, gender, race/ethnicity, and weight status. Our objective was to estimate the proportion of young children in the US who have low levels of active play or high levels of screen time, or who have both these behaviors, and to describe associations with age, gender, race/ethnicity, and weight status. We analyzed data collected during the National Health and Nutrition Examination Surveys 2001-2004, a US nationally representative cross-sectional study. We studied 2964 children aged 4.00 to 11.99 years. Our main outcomes were reported weekly times that the child played or exercised hard enough to sweat or breathe hard (active play), daily hours the child watched television/videos, used computers, or played computer games (screen time), and the combination of low active play and high screen time. Low active play was defined as active play 6 times or less per week. High screen time was defined as more than 2 hours per day. We accounted for the complex survey design in analyses and report proportions and 95% confidence intervals. We used Wald Chi-square to test for differences between proportions. To identify factors associated with low active play and high screen time, we used multivariate logistic regression. Of US children aged 4 to 11 years, 37.3% (95% confidence interval, 34.1% to 40.4%) had low levels of active play, 65.0% (95% CI, 61.4% to 68.5%) had high screen time, and 26.3% (95% CI, 23.8% to 28.9%) had both these behaviors. Characteristics associated with a higher probability of simultaneously having low active play and high screen time were older age, female gender, non-Hispanic black race/ethnicity, and having a BMI-for-age > or =95th percentile of the CDC growth reference. Many young children in the US are reported to have physical activity and screen time behaviors that are inconsistent with recommendations for healthy pediatric development. Children who are overweight, approaching adolescence, girls, and non-Hispanic blacks may benefit most from public health policies and programs aimed at these behaviors.
The Association between Leisure-Time Physical Activity and Risk of Undetected Prediabetes
Wang, Jia; Wu, Yili; Ning, Feng; Zhang, Chaoying
2017-01-01
Aims. The purpose of the study was to assess the effects of leisure-time physical activity on undetected prediabetes. Methods. Data from the National Health and Nutrition Examination Survey 2007–2012 were used in our analyses. Logistic regression was conducted to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) of prediabetes associated with leisure-time physical activity. Results. A total of 8204 subjects were eligible for our analyses. For all subjects, high level of total leisure-time physical activity (OR = 0.78, 95% CI: 0.66, 0.94) and low level of vigorous leisure-time physical activity (OR = 0.72, 95% CI: 0.58, 0.90) were inversely associated with the risk of prediabetes in multivariate-adjusted model. For subjects under 45 years of age, high level of total leisure-time physical activity (OR = 0.78, 95% CI: 0.61, 0.99) and low (OR = 0.61, 95% CI: 0.45, 0.83) and high (OR = 0.72, 95% CI: 0.53, 1.00) level of vigorous leisure-time physical activity were associated with a decreased risk of prediabetes. In the 45 to 65 age group, only high level of total leisure-time physical activity (OR = 0.73, 95% CI: 0.57, 0.95) had protective effect on prediabetes. Conclusions. Leisure-time physical activity may be associated with a decreased risk of prediabetes. PMID:28367452
Yan, Guiyun; Chen, Fuquan; Wu, Yingxiong
2016-01-01
Different from previous researches which mostly focused on linear response control of seismically excited high-rise buildings, this study aims to control nonlinear seismic response of high-rise buildings. To this end, a semi-active control strategy, in which H∞ control algorithm is used and magneto-rheological dampers are employed for an actuator, is presented to suppress the nonlinear vibration. In this strategy, a modified Kalman-Bucy observer which is suitable for the proposed semi-active strategy is developed to obtain the state vector from the measured semi-active control force and acceleration feedback, taking into account of the effects of nonlinearity, disturbance and uncertainty of controlled system parameters by the observed nonlinear accelerations. Then, the proposed semi-active H∞ control strategy is applied to the ASCE 20-story benchmark building when subjected to earthquake excitation and compared with the other control approaches by some control criteria. It is indicated that the proposed semi-active H∞ control strategy provides much better control performances by comparison with the semi-active MPC and Clipped-LQG control approaches, and can reduce nonlinear seismic response and minimize the damage in the buildings. Besides, it enhances the reliability of the control performance when compared with the active control strategy. Thus, the proposed semi-active H∞ control strategy is suitable for suppressing the nonlinear vibration of high-rise buildings.
Hypersexuality and high sexual desire: exploring the structure of problematic sexuality.
Carvalho, Joana; Štulhofer, Aleksandar; Vieira, Armando L; Jurin, Tanja
2015-06-01
The concept of hypersexuality has been accompanied by fierce debates and conflicting conclusions about its nature. One of the central questions under the discussion is a potential overlap between hypersexuality and high sexual desire. With the relevant research in its early phase, the structure of hypersexuality remains largely unknown. The aim of the present study was to systematically explore the overlap between problematic sexuality and high sexual desire. A community online survey was carried out in Croatia in 2014. The data were first cluster analyzed (by gender) based on sexual desire, sexual activity, perceived lack of control over one's sexuality, and negative behavioral consequences. Participants in the meaningful clusters were then compared for psychosocial characteristics. To complement cluster analysis (CA), multigroup confirmatory factor analysis (CFA) of the same four constructs was carried out. Indicators representing the proposed structure of hypersexuality were included: sexual desire, frequency of sexual activity, lack of control over one's sexuality, and negative behavioral outcomes. Psychosocial characteristics such as religiosity, attitudes toward pornography, and general psychopathology were also evaluated. CA pointed to the existence of two meaningful clusters, one representing problematic sexuality, that is, lack of control over one's sexuality and negative outcomes (control/consequences cluster), and the other reflecting high sexual desire and frequent sexual activity (desire/activity cluster). Compared with the desire/activity cluster, individuals from the control/consequences cluster reported more psychopathology and were characterized by more traditional attitudes. Complementing the CA findings, CFA pointed to two distinct latent dimensions-problematic sexuality and high sexual desire/activity. Our study supports the distinctiveness of hypersexuality and high sexual desire/activity, suggesting that problematic sexuality might be more associated with the perceived lack of personal control over sexuality and moralistic attitudes than with high levels of sexual desire and activity. © 2015 International Society for Sexual Medicine.
Compassionate Love Buffers Stress-Reactive Mothers From Fight-or-Flight Parenting
Miller, Jonas G.; Kahle, Sarah; Lopez, Monica; Hastings, Paul D.
2015-01-01
The links among mothers’ compassionate love for their child, autonomic nervous system activity, and parenting behavior during less and more challenging mother–child interactions were examined. Mothers expressed and reported less negative affect when they exhibited autonomic patterns of increased parasympathetic dominance (high parasympathetic and low sympathetic activation) or autonomic coactivation (high parasympathetic and high sympathetic activation) during the less challenging interaction and autonomic coactivation during the more challenging interaction. Compassionate love predicted less reported and observed negativity in mothers who showed increased sympathetic nervous system dominance (high sympathetic and low parasympathetic activation). Compassionate love appeared to help mothers, and particularly those who experienced strong physiological arousal during difficult parenting situations, establish positive socialization contexts for their children and avoid stress-induced adverse parenting. PMID:25329554
Cardiovascular autonomic modulation and activity of carotid baroreceptors at altitude.
Bernardi, L; Passino, C; Spadacini, G; Calciati, A; Robergs, R; Greene, R; Martignoni, E; Anand, I; Appenzeller, O
1998-11-01
1. To assess the effects of acute exposure to high altitude on baroreceptor function in man we evaluated the effects of baroreceptor activation on R-R interval and blood pressure control at high altitude. We measured the low-frequency (LF) and high-frequency (HF) components in R-R, non-invasive blood pressure and skin blood flow, and the effect of baroreceptor modulation by 0. 1-Hz sinusoidal neck suction. Ten healthy sea-level natives and three high-altitude native, long-term sea-level residents were evaluated at sea level, upon arrival at 4970 m and 1 week later.2. Compared with sea level, acute high altitude decreased R-R and increased blood pressure in all subjects [sea-level natives: R-R from 1002+/-45 to 775+/-57 ms, systolic blood pressure from 130+/-3 to 150+/-8 mmHg; high-altitude natives: R-R from 809+/-116 to 749+/-47 ms, systolic blood pressure from 110+/-12 to 125+/-11 mmHg (P<0.05 for all)]. One week later systolic blood pressure was similar to values at sea level in all subjects, whereas R-R remained elevated in sea-level natives. The low-frequency power in R-R and systolic blood pressure increased in sea-level natives [R-R-LF from 47+/-8 to 65+/-10% (P<0.05), systolic blood pressure-LF from 1.7+/-0. 3 to 2.6+/-0.4 ln-mmHg2 (P<0.05)], but not in high-altitude natives (R-R-LF from 32+/-13 to 38+/-19%, systolic blood pressure-LF from 1. 9+/-0.5 to 1.7+/-0.8 ln-mmHg2). The R-R-HF decreased in sea-level natives but not in high-altitude natives, and no changes occurred in systolic blood pressure-HF. These changes remained evident 1 week later. Skin blood flow variability and its spectral components decreased markedly at high altitude in sea-level natives but showed no changes in high-altitude natives. Neck suction significantly increased the R-R- and systolic blood pressure-LF in all subjects at both sea level and high altitude.3. High altitude induces sympathetic activation in sea-level natives which is partially counteracted by active baroreflex. Despite long-term acclimatization at sea level, high-altitude natives also maintain active baroreflex at high altitude but with lower sympathetic activation, indicating a persisting high-altitude adaptation which may be genetic or due to baroreflex activity not completely lost by at least 1 year's sea-level residence.
Regional brain responses in nulliparous women to emotional infant stimuli.
Montoya, Jessica L; Landi, Nicole; Kober, Hedy; Worhunsky, Patrick D; Rutherford, Helena J V; Mencl, W Einar; Mayes, Linda C; Potenza, Marc N
2012-01-01
Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infant cries of two distress levels (low and high) and unknown infant faces of varying affect (happy, sad, and neutral) in a randomized, counter-balanced order. Brain activation was subsequently correlated with scores on the Behavioral Inhibition System/Behavioral Activation System scale. Infant cries activated bilateral superior and middle temporal gyri (STG and MTG) and precentral and postcentral gyri. Activation was greater in bilateral temporal cortices for low- relative to high-distress cries. Happy relative to neutral faces activated the ventral striatum, caudate, ventromedial prefrontal, and orbitofrontal cortices. Sad versus neutral faces activated the precuneus, cuneus, and posterior cingulate cortex, and behavioral activation drive correlated with occipital cortical activations in this contrast. Behavioral inhibition correlated with activation in the right STG for high- and low-distress cries relative to pink noise. Behavioral drive correlated inversely with putamen, caudate, and thalamic activations for the comparison of high-distress cries to pink noise. Reward-responsiveness correlated with activation in the left precentral gyrus during the perception of low-distress cries relative to pink noise. Our findings indicate that infant cry stimuli elicit activations in areas implicated in auditory processing and social cognition. Happy infant faces may be encoded as rewarding, whereas sad faces activate regions associated with empathic processing. Differences in motivational tendencies may modulate neural responses to infant cues.
The Educational Soundscape: Participation and Perception in Japanese High School English Lessons
ERIC Educational Resources Information Center
Meacham, Sarah S.
2007-01-01
In this article I discuss the emergence of practices of "hearing" in the midst of English language learning activities. I focus on listening activities during oral English lessons at two public high schools in Tokyo, Japan. One setting is a liberal arts high school. The other is a technical high school where students are trained in…
Active Learning of Geometrical Optics in High School: The ALOP Approach
ERIC Educational Resources Information Center
Alborch, Alejandra; Pandiella, Susana; Benegas, Julio
2017-01-01
A group comparison experiment of two high school classes with pre and post instruction testing has been carried out to study the suitability and advantages of using the active learning of optics and photonics (ALOP) curricula in high schools of developing countries. Two parallel, mixed gender, 12th grade classes of a high school run by the local…
Guo, Yinfeng; Song, Zhixia; Zhou, Min; Yang, Ying; Zhao, Yu; Liu, Bicheng; Zhang, Xiaoliang
2017-01-01
Macrophage infiltration has been linked to the pathogenesis of diabetic nephropathy (DN). However, how infiltrating macrophages affect the progression of DN is unknown. Although infiltrating macrophages produce pro-inflammatory mediators and induce apoptosis in a variety of target cells, there are no studies in podocytes. Therefore, we tested the contribution of macrophages to podocytes apoptosis in DN. in vivo experiments showed that apoptosis in podocytes was increased in streptozocin (STZ)-induced diabetic rats compared with control rats and that this apoptosis was accompanied by increased macrophages infiltration in the kidney. Then, we established a co-culture system to study the interaction between macrophages and podocytes in the absence or presence of high glucose. Macrophages did not trigger podocytes apoptosis when they were co-cultured in the absence of high glucose in a transwell co-culture system. Additionally, although podocyte apoptosis was increased after high glucose stimulation, there was a further enhancement of podocyte apoptosis when podocytes were co-cultured with macrophages in the presence of high glucose compared with podocytes cultured alone in high glucose. Mechanistically, we found that macrophages were activated when they were exposed to high glucose, displaying pro-inflammatory M1 polarization. Furthermore, conditioned media (CM) from such high glucose-activated M1 macrophages (HG-CM) trigged podocytes apoptosis in a reactive oxygen species (ROS)-p38mitogen-activated protein kinases (p38MAPK) dependent manner, which was abolished by either a ROS inhibitor (Tempo) or a p38MAPK inhibitor (SB203580). Finally, we identified tumor necrosis factor (TNF-α) as a key mediator of high glucose-activated macrophages to induce podocytes apoptosis because an anti-TNF-α neutralizing antibody blunted the apoptotic response, excess ROS generation and p38MPAK activation in podocytes induced by HG-CM. Moreover, addition of recombinant TNF-α similarly resulted in podocytes apoptosis. In summary, the TNF-α that was released by high glucose-activated macrophages promoted podocytes apoptosis via ROS-p38MAPK pathway. Blockade of TNF-α secretion from high glucose activated macrophages and ROS-p38MAPK pathway might be effective therapeutic options to limit podocytes apoptosis and delay the progression of diabetic nephropathy. PMID:28881810
A Belief-Behavior Gap? Exploring Religiosity and Sexual Activity among High School Seniors
ERIC Educational Resources Information Center
Leonard, Kathleen Cobb; Scott-Jones, Diane
2010-01-01
Religiosity, sexual activity, and contraception were examined via questionnaires and interviews in a diverse sample of 118 high school seniors. The majority reported religion to be important; importance and frequency ratings declined from private (e.g., prayer) to public (e.g., group activities) components of religion. Most were sexually active…
Human Spaceflight: Activities for the Intermediate and Junior High Student.
ERIC Educational Resources Information Center
Hartsfield, John W.; Hartsfield, Kendra J.
Since its beginning, space science has created high interest and continues to prod the imagination of students. This activity packet, which has been designed to enhance the curriculum and challenge gifted students, contains background information on spaceflight as well as 24 interdisciplinary classroom activities, 3 crossword puzzles, and 3 word…
Teaching/Learning Geometric Transformations in High-School with DGS
ERIC Educational Resources Information Center
Ferrarello, Daniela; Mammana, Maria Flavia; Pennisi, Mario
2014-01-01
In this paper, we present the results of an experimental sequence of classroom activities on geometric transformations, proposed to high-school students. The activity is based on the use of a dynamic geometry system. Planned by a group of four people, two university professors and two research teachers, the activity has been elaborated together…
Earth-Space Science Activity Syllabus for Elementary and Junior High School Teachers of Science.
ERIC Educational Resources Information Center
Maier, Jack; And Others
This syllabus is a collection of earth-space science laboratory activities and demonstrations intended for use at the elementary and junior high school levels. The activities are grouped into eight subject sections: Astronomy, Light, Magnetism, Electricity, Geology, Weather, Sound, and Space. Each section begins with brief background information,…
ERIC Educational Resources Information Center
Hillman, Charles H.; Belopolsky, Artem V.; Snook, Erin M.; Kramer, Arthur F.; McAuley, Edward
2004-01-01
Electrocortical and behavioral responses of low, moderate, and high physically active older adults where compared with a younger control group on neutral and incompatible conditions of a flankers task. Compared to younger adults, high and moderate active older adults exhibited increased event-related potentials component P3 amplitude for the…
High School Students' Affective Reaction to English Speaking Activities
ERIC Educational Resources Information Center
Jorquera Torres, Oliver Camilo; Mendoza Zapata, Jhon Eliot; Díaz Larenas, Claudio Heraldo
2017-01-01
This study aims to measure fifty-two high school students' affective reactions after doing individual and pair-based speaking activities then completing a semantic differential scale of nine bipolar adjectives. Results do not show significant statistical differences between the two types of activities or the schools involved in this study, but…
Physical Activity and Cervical Cancer Testing among American Indian Women
ERIC Educational Resources Information Center
Muus, Kyle J.; Baker-Demaray, Twyla B.; Bogart, T. Andy; Duncan, Glen E.; Jacobsen, Clemma; Buchwald, Dedra S.; Henderson, Jeffrey A.
2012-01-01
Purpose: Studies have shown that women who engage in high levels of physical activity have higher rates of cancer screening, including Papanicalaou (Pap) tests. Because American Indian (AI) women are at high risk for cervical cancer morbidity and mortality, we examined Pap screening prevalence and assessed whether physical activity was associated…
The Effects of Physical Education Requirements on Physical Activity of Young Adults
ERIC Educational Resources Information Center
Mears, Derrick
2008-01-01
The purpose of this study was to determine if requiring multiple credits of high school physical education for graduation has an impact on promoting physical activity in young adults. Participants in this study (N=361) were surveyed concerning their high school physical education experiences and current performance of physical activity. Results…
High School Girls' Perceptions of Selected Fitness Activities
ERIC Educational Resources Information Center
Wilkinson, Carol; Bretzing, Robyn
2011-01-01
High school students, and particularly girls, are not very active (Centers for Disease Control and Prevention, 2006). To help girls develop the abilities to enjoy lifetime, healthy physical activity, physical educators need to provide curricula that will achieve this goal. In the process, they need to make sure they are aligned with the current…
ERIC Educational Resources Information Center
Granger, Christopher John
2014-01-01
This study was designed to investigate the influence of student participation in extracurricular activities, as perceived by rural high school principals, with successful extracurricular programs. Participating principals were asked about their perceptions on the influence of student participation in extracurricular activities on student…
Marsden, J. R.; Dawson, I. M. P.
1974-01-01
Histochemical enzymatic studies were performed on 30 freshly resected large bowel carcinomas, 30 samples of normal colonic epithelium, and six samples of the histologically normal epithelium (so-called transitional epithelium) immediately adjacent to a carcinoma. Five enzymes were studied: nicotine adenine dinucleotide tetrazolium reductase (NADH-TR), glucose-6-phosphate dehydrogenase, succinate dehydrogenase, monoamine oxidase, and acid phosphatase. Quantitative and qualitative differences in enzyme activity were observed between normal, transitional, and carcinomatous mucosa as follows: monoamine oxidase activity was moderate in normal mucosa, high in transitional mucosa, and low in carcinoma. Succinate dehydrogenase activity was high in transitional mucosa and low or moderate in normal and carcinomatous mucosa. Glucose-6-phosphate dehydrogenase activity showed a gradation from low in normal mucosa to high in carcinoma while acid phosphatase showed the reverse of this pattern. The tetrazolium reductase activity was low or moderate in normal and transitional mucosa and high in carcinoma. These differences in enzyme activity and their possible clinical and metabolic significance are discussed. ImagesFig 2Fig 3 PMID:4154840
Mao, Yanhui; Roberts, Scott; Pagliaro, Stefano; Csikszentmihalyi, Mihaly; Bonaiuto, Marino
2016-01-01
Eudaimonistic identity theory posits a link between activity and identity, where a self-defining activity promotes the strength of a person's identity. An activity engaged in with high enjoyment, full involvement, and high concentration can facilitate the subjective experience of flow. In the present paper, we hypothesized in accordance with the theory of psychological selection that beyond the promotion of individual development and complexity at the personal level, the relationship between flow and identity at the social level is also positive through participation in self-defining activities. Three different samples (i.e., American, Chinese, and Spanish) filled in measures for flow and social identity, with reference to four previously self-reported activities, characterized by four different combinations of skills (low vs. high) and challenges (low vs. high). Findings indicated that flow was positively associated with social identity across each of the above samples, regardless of participants' gender and age. The results have implications for increasing social identity via participation in self-defining group activities that could facilitate flow.
Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony T.; ...
2016-02-09
To begin this abstract, amorphous metal-oxide semiconductors offer the high carrier mobilities and excellent large-area uniformity required for high performance, transparent, flexible electronic devices; however, a critical bottleneck to their widespread implementation is the need to activate these materials at high temperatures which are not compatible with flexible polymer substrates. The highly controllable activation of amorphous indium gallium zinc oxide semiconductor channels using ionic liquid gating at room temperature is reported. Activation is controlled by electric field-induced oxygen migration across the ionic liquid-semiconductor interface. In addition to activation of unannealed devices, it is shown that threshold voltages of a transistormore » can be linearly tuned between the enhancement and depletion modes. Finally, the first ever example of transparent flexible thin film metal oxide transistor on a polyamide substrate created using this simple technique is demonstrated. Finally, this study demonstrates the potential of field-induced activation as a promising alternative to traditional postdeposition thermal annealing which opens the door to wide scale implementation into flexible electronic applications.« less
Mao, Yanhui; Roberts, Scott; Pagliaro, Stefano; Csikszentmihalyi, Mihaly; Bonaiuto, Marino
2016-01-01
Eudaimonistic identity theory posits a link between activity and identity, where a self-defining activity promotes the strength of a person’s identity. An activity engaged in with high enjoyment, full involvement, and high concentration can facilitate the subjective experience of flow. In the present paper, we hypothesized in accordance with the theory of psychological selection that beyond the promotion of individual development and complexity at the personal level, the relationship between flow and identity at the social level is also positive through participation in self-defining activities. Three different samples (i.e., American, Chinese, and Spanish) filled in measures for flow and social identity, with reference to four previously self-reported activities, characterized by four different combinations of skills (low vs. high) and challenges (low vs. high). Findings indicated that flow was positively associated with social identity across each of the above samples, regardless of participants’ gender and age. The results have implications for increasing social identity via participation in self-defining group activities that could facilitate flow. PMID:26924995
Seasonal Variation of High-Latitude Geomagnetic Activity in Individual Years
NASA Astrophysics Data System (ADS)
Tanskanen, E. I.; Hynönen, R.; Mursula, K.
2017-10-01
We study the seasonal variation of high-latitude geomagnetic activity in individual years in 1966-2014 (solar cycles 20-24) by identifying the most active and the second most active season based on westward electrojet indices AL (1966-2014) and IL (1995-2014). The annual maximum is found at either equinox in two thirds and at either solstice in one third of the years examined. The traditional two-equinox maximum pattern is found in roughly one fourth of the years. We found that the seasonal variation of high-latitude geomagnetic activity closely follows the solar wind speed. While the mechanisms leading to the two-equinox maxima pattern are in operation, the long-term change of solar wind speed tends to mask the effect of these mechanisms for individual years. Large cycle-to-cycle variation is found in the seasonal pattern: equinox maxima are more common during cycles 21 and 22 than in cycles 23 or 24. Exceptionally long winter dominance in high-latitude activity and solar wind speed is seen in the declining phase of cycle 23, after the appearance of the long-lasting low-latitude coronal hole.
Su, Yu; Wang, Weidong; Wu, Di; Huang, Wei; Wang, Mengzi; Zhu, Guibing
2018-05-15
An integrated approach to document high ammonium oxidation rate in Guanjinggang constructed wetland (GJG-CW) was performed and the results showed that the substantial ammonium oxidation rate could be obtained by enhancing Ammonia Oxidizing Bacteria (AOB) activity rather than Ammonia Oxidizing Archaea (AOA) activity. In the plant-bed/ditch system, ditch center and plant-bed fringe were two active zones for NH 4 + -N removal with ammonium oxidation rate peaking at 2.98±0.04 and 2.15±0.02mgNkg -1 d -1 , respectively. The enhanced AOB activity were achieved by increasing water level fluctuations, extending hydraulic retention time (HRT) and stimulating substrate availability, which subsequently enhanced NH 4 + -N removal by 34.06% in GJG-CW. However, the high AOB activity was not correlated with high AOB abundance, but was instead mostly determined by specific AOB taxa, particularly Nitrosomonas, which dominated in the active AOB. The increased cell-specific AOA activity and high AOA diversity were also achieved using those engineering measures. Although the AOA activity decreased overall with extended HRT and increased NH 4 + -N contents in GJG-CW, AOA still played a major role on ammonium oxidation in plant-bed soil. The study illustrated that artificially enhancing AOB activity and certain species in anthropogenically polluted water ecosystems would be an effective strategy to improve NH 4 + -N removal. Copyright © 2017 Elsevier B.V. All rights reserved.
Effect of sodium intake on sympathetic and hemodynamic response to thermal receptor stimulation.
DiBona, Gerald F; Jones, Susan Y
2003-02-01
Low dietary sodium intake increases central nervous system angiotensin activity, which increases basal renal sympathetic nerve activity and shifts its arterial baroreflex control to a higher level of arterial pressure. This results in a higher level of renal sympathetic nerve activity for a given level of arterial pressure during low dietary sodium intake than during either normal or high dietary sodium intake, in which there is less central angiotensin activity. Peripheral thermal receptor stimulation overrides arterial baroreflex control and produces a pressor response, tachycardia, increased renal sympathetic nerve activity, and renal vasoconstriction. To test the hypothesis that increased central angiotensin activity would enhance the responses to peripheral thermal receptor stimulation, anesthetized normal rats in balance on low, normal, and high dietary sodium intake were subjected to acute peripheral thermal receptor stimulation. Low sodium rats had greater increases in renal sympathetic nerve activity, greater decreases in RBF, and greater increases in renal vascular resistance than high sodium rats. Responses of normal sodium rats were between those of low and high sodium rats. Arterial pressure and heart rate responses were not different among dietary groups. Spontaneously hypertensive rats, known to have increased central nervous system angiotensin activity, also had greater renal sympathoexcitatory and vasoconstrictor responses than normotensive Wistar-Kyoto rats. These results support the view that increased central nervous system angiotensin activity alters arterial baroreflex control of renal sympathetic nerve activity such that the renal sympathoexcitatory and vasoconstrictor responses to peripheral thermoreceptor stimulation are enhanced.
NASA Astrophysics Data System (ADS)
Tsao, Sinchai; Adam, Tanja C.; Goran, Michael I.; Singh, Manbir
2012-03-01
The factors behind the neural mechanisms that motivate food choice and obesity are not well known. Furthermore, it is not known when these neural mechanisms develop and how they are influenced by both genetic and environmental factors. This study uses fMRI together with clinical data to shed light on the aforementioned questions by investigating how appetite-related activation in the brain changes with low versus high caloric foods in pre-pubescent girls. Previous studies have shown that obese adults have less striatal D2 receptors and thus reduced Dopamine (DA) signaling leading to the reward-deficit theory of obesity. However, overeating in itself reduces D2 receptor density, D2 sensitivity and thus reward sensitivity. The results of this study will show how early these neural mechanisms develop and what effect the drastic endocrinological changes during puberty has on these mechanisms. Our preliminary results showed increased activations in the Putamen, Insula, Thalamus and Hippocampus when looking at activations where High Calorie > Low Calorie. When comparing High Calorie > Control and Low Calorie > Control, the High > Control test showed increased significant activation in the frontal lobe. The Low > Control also yielded significant activation in the Left and Right Fusiform Gyrus, which did not appear in the High > Control test. These results indicate that the reward pathway activations previously shown in post-puberty and adults are present in pre-pubescent teens. These results may suggest that some of the preferential neural mechanisms of reward are already present pre-puberty.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yifan; Zhang, Shangrong; Li, Shu Jie, E-mail: shujieli@nankai.edu.cn
Highlights: •Hv1 is expressed in highly metastatic glioma cell. •Zn{sup 2+} ions induces apoptosis in highly metastatic glioma cells. •Zn{sup 2+} ions markedly inhibit proton secretion. •Zn{sup 2+} ions reduce the gelatinase activity. •Inhibition of Hv1 activity via Zn{sup 2+} ions can effectively retard the cancer growth. -- Abstract: In contrast to the voltage-gated K{sup +} channels, the voltage-gated proton channel Hv1 contains a voltage-sensor domain but lacks a pore domain. Here, we showed that Hv1 is expressed in the highly metastatic glioma cell SHG-44, but lowly in the poorly metastatic glioma cell U-251. Inhibition of Hv1 activity by 140more » μM zinc chloride induces apoptosis in the human highly metastatic glioma cells. Zn{sup 2+} ions markedly inhibit proton secretion, and reduce the gelatinase activity in the highly metastatic glioma cells. In vivo, the glioma tumor sizes of the implantation of the SHG-44 xenografts in nude mice that were injected zinc chloride solution, were dramatically smaller than that in the controlled groups. The results demonstrated that the inhibition of Hv1 activity via Zn{sup 2+} ions can effectively retard the cancer growth and suppress the cancer metastasis by the decrease of proton extrusion and the down-regulation of gelatinase activity. Our results suggest that Zn{sup 2+} ions may be used as a potential anti-glioma drug for glioma therapy.« less
Individual, Social, and Environmental Correlates of Active Transportation Patterns in French Women.
Perchoux, Camille; Enaux, Christophe; Oppert, Jean-Michel; Menai, Mehdi; Charreire, Hélène; Salze, Paul; Weber, Christiane; Hercberg, Serge; Feuillet, Thierry; Hess, Franck; Roda, Célina; Simon, Chantal; Nazare, Julie-Anne
2017-01-01
The objectives were (1) to define physical activity (PA) and sedentary behaviors (SB) patterns in daily life contexts (work, leisure, and transportation) in French working women from NutriNet-Santé web-cohort and (2) to identify pattern(s) of active transportation and their individual, social, and environmental correlates. 23,432 participants completed two questionnaires to evaluate PA and SB in daily life contexts and individual representations of residential neighborhood and transportation modes. Hierarchical cluster analysis was performed which identified 6 distinct movement behavior patterns: (i) active occupation, high sedentary leisure, (ii) sedentary occupation, low leisure, (iii) sedentary transportation, (iv) sedentary occupation and leisure, (v) active transportation, and (vi) active leisure. Multinomial logistic regressions were performed to identify correlates of the "active transportation" cluster. The perceived environmental characteristics positively associated with "active transportation" included "high availability of destinations around home," "presence of bicycle paths," and "low traffic." A "positive image of walking/cycling," the "individual feeling of being physically active," and a "high use of active transport modes by relatives/friends" were positively related to "active transportation," identified as a unique pattern regarding individual and environmental correlates. Identification of PA and SB context-specific patterns will help to understand movement behaviors' complexity and to design interventions to promote active transportation in specific subgroups.
ERIC Educational Resources Information Center
Small, Meg L.; Waterman, Emily; Lender, Taylor
2017-01-01
To increase student engagement, many universities are adopting high-impact educational practices that include study abroad opportunities, faculty mentoring, internships, service learning, challenging coursework, and research experiences; these institutions are also intentionally promoting high-impact cocurricular activities such as community…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-26
... Activities: Requests for Comments; Clearance of Renewed Approval of Information Collection: High Density... records of slot transfers at High Density Traffic Airports. The information is provided by air carriers and commuter operators, or other persons holding a slot at High Density Airports. DATES: Written...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-27
... Activities: Requests for Comments; Clearance of Renewed Approval of Information Collection: High Density... maintain accurate records of slot transfers at High Density Traffic Airports. The information is provided by air carriers and commuter operators, or other persons holding a slot at High Density Airports...
Sino-Austrian High-Tech Acupuncture Network—Annual Report 2016
Litscher, Gerhard
2017-01-01
The Sino-Austrian High-Tech Acupuncture Research Network was founded in 2005 and has been growing ever since. The network comprises many partners from China and is highly involved in research and education activities. This report introduces the network’s activities in the year 2016. PMID:28930227
Sino-Austrian High-Tech Acupuncture Network: Annual Report 2017
2018-01-01
The Sino-Austrian High-Tech Acupuncture Research Network was founded in 2005 and has been growing ever since. The network comprises many partners from China and is highly involved in research and education activities. This report introduces the network’s activities in the year 2017. PMID:29329241
Biological evaluation of certain substituted hydantoins and benzalhydantoins against microbes
NASA Astrophysics Data System (ADS)
Hidayat, Ika-Wiani; Thu, Yee Yee; Black, David St. C.; Read, Roger W.
2016-02-01
Twenty-three synthetic (thio)hydantoins and benzalhydantoins were evaluated for antimicrobial activity against Candida albicans, Malassezia furfur, Escherichia coli and Staphylococcus aureus, by the paper disc diffusion method. 3-n-butyl-4'-nitrobenzalhydantoin showed very high activity against E. coli and high selectivity with respect to the other microorganisms, while 3-n-butyl-2'-bromo-4',5'-dimethoxybenzal hydantoin demonstrated very high selectivity in its activity against M. furfur and S. aureus. These compounds show the most promise as drug lead compounds.
High Energy Astrophysics Program
NASA Technical Reports Server (NTRS)
1996-01-01
This report reviews activities performed-by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, visiting the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA); X-ray Timing Experiment (XTE); X-ray Spectrometer (XRS); Astro-E; High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Research and Programmatic Support
NASA Technical Reports Server (NTRS)
Angelini, Lorella
1998-01-01
This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Program (HEAP)
NASA Technical Reports Server (NTRS)
Angelini, Lorella; Corcoran, Michael; Drake, Stephen; McGlynn, Thomas A.; Snowden, Stephen; Mukai, Koji; Cannizzo, John; Lochner, James; Rots, Arnold; Christian, Eric;
1998-01-01
This report reviews activities performed by the members of the USRA contract team during the 6 months of the reporting period and projected activities during the coming 6 months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in astrophysics. Supported missions include advanced Satellite for Cosmology and Astrophysics (ASCA), X-Ray Timing Experiment (XTE), X-Ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC) and others.
High Energy Astrophysics Program (HEAP)
NASA Technical Reports Server (NTRS)
Angelini, L.
1998-01-01
This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Research and Programmatic Support
NASA Technical Reports Server (NTRS)
Angelini, L. (Editor)
1997-01-01
This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
Pain Catastrophising Affects Cortical Responses to Viewing Pain in Others
Fallon, Nicholas
2015-01-01
Pain catastrophising is an exaggerated cognitive attitude implemented during pain or when thinking about pain. Catastrophising was previously associated with increased pain severity, emotional distress and disability in chronic pain patients, and is also a contributing factor in the development of neuropathic pain. To investigate the neural basis of how pain catastrophising affects pain observed in others, we acquired EEG data in groups of participants with high (High-Cat) or low (Low-Cat) pain catastrophising scores during viewing of pain scenes and graphically matched pictures not depicting imminent pain. The High-Cat group attributed greater pain to both pain and non-pain pictures. Source dipole analysis of event-related potentials during picture viewing revealed activations in the left (PHGL) and right (PHGR) paraphippocampal gyri, rostral anterior (rACC) and posterior cingulate (PCC) cortices. The late source activity (600–1100 ms) in PHGL and PCC was augmented in High-Cat, relative to Low-Cat, participants. Conversely, greater source activity was observed in the Low-Cat group during the mid-latency window (280–450 ms) in the rACC and PCC. Low-Cat subjects demonstrated a significantly stronger correlation between source activity in PCC and pain and arousal ratings in the long latency window, relative to high pain catastrophisers. Results suggest augmented activation of limbic cortex and higher order pain processing cortical regions during the late processing period in high pain catastrophisers viewing both types of pictures. This pattern of cortical activations is consistent with the distorted and magnified cognitive appraisal of pain threats in high pain catastrophisers. In contrast, high pain catastrophising individuals exhibit a diminished response during the mid-latency period when attentional and top-down resources are ascribed to observed pain. PMID:26186545
Swannell, Ellen R; Brown, Christopher A; Jones, Anthony K P; Brown, Richard J
2016-03-01
Theory suggests that as activation of pain concepts in memory increases, so too does subsequent pain perception. Previously, researchers have found that activating pain concepts in memory increases pain perception of subsequent painful stimuli, relative to neutral information. However, they have not attempted to quantify the nature of the association between information studied and ensuing pain perception. We subliminally presented words that had either a low or high degree of association to the word 'pain,' although this was only partially successful and some words were consciously perceived. Participants then received randomized laser heat stimuli, delivered at 1 of 3 intensity levels (low, moderate, high), and we measured the effect of this on behavioral and electrophysiological measures of pain. Participants (N = 27) rated moderate- and high-intensity laser stimuli as more painful after viewing high relative to low associates of pain; these effects remained present when we controlled for measures of mood, anxiety, and physical symptom reporting. Similar effects were observed physiologically, with higher stimulus negativity preceding after high relative to low associates and greater amplitudes for the N2 component of the laser-evoked potential after presentation of high associates in the moderate and high laser intensity conditions. These data support activation-based models of the effects of memory on pain perception. Consistent with current theories of memory and pain, we found that high, relative to low activation of pain concepts in memory increased psychological and physiological responses to laser-induced pain. The effect remained regardless of whether participants showed conscious awareness of activation. Theoretical and clinical implications are discussed. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
Theodorakis, Christopher W; Adams, S Marshall; Smith, Chandra; Rotter, Jamie; Hay, Ashley; Eslick, Joy
2017-12-01
Department of Defense lands are essential for providing important habitat for threatened, endangered, and at-risk species (TER-S). However, there is little information on the effects of military-related contaminants on TER-S on these lands in field situations. Thus, this study examined genotoxicity and oxidative stress in gopher tortoises (Gopherus polyphemus) on Camp Shelby, MS-the largest known population of this species, which is listed as an "endangered species" in Mississippi and a "threatened species" by the U.S. government. Blood was collected from tortoises at 19 different sites on the base with different levels of habitat quality (high-quality and low-quality habitat) and military activity (high, low, and no military activity). Oxidative stress was quantified as lipid peroxidation and GSSG/GSH ratios, while DNA damage was determined using flow cytometry. Our results suggest that: (1) for tortoises residing in low-quality habitats, oxidative stress and DNA damage increased with increasing military activity, while in high-quality habitats, oxidative stress and DNA damage decreased with increasing military activity; (2) in the absence of military activity, tortoises in high-quality habitat had higher levels of oxidative stress and DNA damage than those in low-quality habitat, and (3) there were interactions between military activity, habitat quality, and landuse in terms of the amount of observable DNA damage and oxidative stress. In particular, on high-quality habitat, tortoises from areas with high levels of military activity had lower levels of oxidative stress and DNA damage biomarkers than on reference sites. This may represent a compensatory or hormetic response. Conversely, on low-quality habitats, the level of oxidative stress and DNA damage was lower on the reference sites. Thus, tortoises on higher-quality habitats may have a greater capacity for compensatory responses. In terms of management implications, it is suggested that low quality habitats should be a higher priority for remediation, and lower priority for conducting military activities.
Does disease activity at start of biologic therapy influence work-loss in RA patients?
Olofsson, Tor; Johansson, Kari; Eriksson, Jonas K; van Vollenhoven, Ronald; Miller, Heather; Petersson, Ingemar F; Askling, Johan; Neovius, Martin
2016-04-01
To compare work-loss in RA patients starting their first biologic with high vs moderate disease activity. We identified all RA patients aged 20-63 years in the Swedish Biologics Register who started their first biologic 2007-09 with high disease activity (DAS28 >5.1; n = 868) or moderate disease activity (DAS28 3.2-5.1; n = 854). Work days lost, defined as sick leave and disability pension days from the Swedish Social Insurance Agency, were assessed over 5 years after first bio-start. We estimated between-group mean differences adjusted for age, sex, calendar year, education level, disease duration, comorbidities and work-loss the month before bio-start. During 5 years after anti-TNF start, mean monthly work days lost declined from 16.0 to 9.2 (42%; P < 0.001) in patients with high disease activity at baseline and from 12.0 to 7.2 (40%; P < 0.001) in patients with moderate disease activity, with no between-group difference (adjusted mean difference 0.81; 95% CI - 0.44, 2.05). Accumulated 5-year work-loss was, however, higher in the high activity group (724 vs 548 days; adjusted mean difference 70; 95% CI 20, 120), but after stratification on baseline disability pension status, no differences in accumulated work-loss were detected. Substantial work-loss was seen in both patients with high and patients with moderate disease activity at anti-TNF start, with a 5-year decline in mean monthly work days lost by ∼40% in both groups and no between-group difference. Accumulated work-loss over 5 years was higher in the high-activity group, which may be explained by differences in baseline disability pension status. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Hyper-parenting is negatively associated with physical activity among 7-12year olds.
Janssen, Ian
2015-04-01
To explore associations between helicopter, little emperor, tiger mom, and concerted cultivation hyper-parenting styles with child physical activity. 724 North American parents of 7-12 year olds completed a survey (May, 2014) that assessed their engagement in the hyper-parenting styles and the frequency that their child played outdoors, walked/bicycled, and played organized sports. Z-scores were generated for each hyper-parenting style and four groups were created: low (<-1 SD), below average (-1 to -0.49 SD), average (-0.50 to 0.50 SD), above average (0.51 to 0.1.0 SD), and high (>1 SD). Outdoor play, active transportation, and organized sport did not differ across helicopter parenting groups. Children in the low little emperor group had higher (P<0.005) outdoor play and active transportation scores than children in the average, above average, and high groups (exception: high group for outdoor play). Children in the low tiger mom and concerted cultivation groups had higher (P<0.005) outdoor play, active transportation, and organized sport scores than children in the average, above average, and high groups (exceptions: average and high tiger mom groups for organized sport). Little emperor, tiger mom, and concerted cultivation parenting styles were associated with lower physical activity among 7-12 year olds. Copyright © 2015. Published by Elsevier Inc.
Active Learning Strategies for Phenotypic Profiling of High-Content Screens.
Smith, Kevin; Horvath, Peter
2014-06-01
High-content screening is a powerful method to discover new drugs and carry out basic biological research. Increasingly, high-content screens have come to rely on supervised machine learning (SML) to perform automatic phenotypic classification as an essential step of the analysis. However, this comes at a cost, namely, the labeled examples required to train the predictive model. Classification performance increases with the number of labeled examples, and because labeling examples demands time from an expert, the training process represents a significant time investment. Active learning strategies attempt to overcome this bottleneck by presenting the most relevant examples to the annotator, thereby achieving high accuracy while minimizing the cost of obtaining labeled data. In this article, we investigate the impact of active learning on single-cell-based phenotype recognition, using data from three large-scale RNA interference high-content screens representing diverse phenotypic profiling problems. We consider several combinations of active learning strategies and popular SML methods. Our results show that active learning significantly reduces the time cost and can be used to reveal the same phenotypic targets identified using SML. We also identify combinations of active learning strategies and SML methods which perform better than others on the phenotypic profiling problems we studied. © 2014 Society for Laboratory Automation and Screening.
Predictors of participation in sports after hip and knee arthroplasty.
Williams, Daniel H; Greidanus, Nelson V; Masri, Bassam A; Duncan, Clive P; Garbuz, Donald S
2012-02-01
While the primary objective of joint arthroplasty is to improve patient quality of life, pain, and function, younger active patients often demand a return to higher function that includes sporting activity. Knowledge of rates and predictors of return to sports will help inform expectations in patients anticipating return to sports after joint arthroplasty. We measured the rate of sports participation at 1 year using the UCLA activity score and explored 11 variables, including choice of procedure/prosthesis, that might predict return to a high level of sporting activity, when controlling for potential confounding variables. We retrospectively evaluated 736 patients who underwent primary metal-on-polyethylene THA, metal-on-metal THA, hip resurfacing arthroplasty, revision THA, primary TKA, unicompartmental knee arthroplasty, and revision TKA between May 2005 and June 2007. We obtained UCLA activity scores on all patients; we defined high activity as a UCLA score of 7 or more. We evaluated patient demographics (age, sex, BMI, comorbidity), quality of life (WOMAC score, Oxford Hip Score, SF-12 score), and surgeon- and procedural/implant-specific variables to identify factors associated with postoperative activity score. Minimum followup was 11 months (mean, 12.1 months; range, 11-13 months). Preoperative UCLA activity score, age, male sex, and BMI predicted high activity scores. The type of operation and implant characteristics did not predict return to high activity sports. Our data suggest patient-specific factors predict postoperative activity rather than factors specific to type of surgery, implant, or surgeon factors. Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.
Tan, Songwen; Cui, Chunzhi; Hou, Yang; Chen, Xuncai; Xu, Aiqin; Li, Weiguo; You, Hong
2017-01-30
A technique is proposed to treat saline hazardous wastewater by using marine activated sludge, cultivated with sea mud as seed. Since the developed marine activated sludge had phenol-tolerant microorganisms (MAS-1, MAS-2 and MAS-3) which originated from the ocean, it was envisaged that these bacteria could survive and breakdown phenol in saline environments. In this work, typical phenol-tolerant microorganisms were isolated from the marine activated sludge and identified. After a hierarchical acclimation process, the marine activated sludge was used to treat the industrial phenolic wastewater with high salinity. The marine activated sludge was able to break down phenol and other organic components effectively and efficiently in treating the wastewater with salinity of 5.7% w/v. The results showed a high removal of phenol (99%), COD (80%) and NH 3 -N (68%). Copyright © 2016 Elsevier Ltd. All rights reserved.
Dynamic pesticide removal with activated carbon fibers.
Martín-Gullón, I; Font, R
2001-02-01
Rapid small-scale minicolumn tests were carried out to simulate the atrazine adsorption in water phase with three pelletized pitch-based activated carbon fibers (ACF) and one commercial granular activated carbon (GAC). Initial atrazine solutions were prepared with pretreated ground water. Minicolumn tests showed that the performance of highly activated carbon fibers (surface area of 1700 m2/g) is around 7 times better than the commercial GAC (with surface area at around 1100 m2/g), whereas carbon fibers with medium activation degree (surface area of 1500 m2/g) had a removal efficiency worse than the commercial carbon. The high removal efficiency of the highly activated ACF is due to the wide-opened microstructure of the material, with an appreciable contribution of the low size mesopores, maintaining at these conditions a fast kinetic adsorption rate rather than a selective adsorbent for micropollutants vs. natural organic matter.
Reifegerste, Doreen; Rossmann, Constanze
2017-02-01
Past research in social and health psychology has shown that affiliation motivation is associated with health behavior, especially for high-risk populations, suggesting that targeting this motivation could be a promising strategy to promote physical activity. However, the effects that affiliation appeals (e.g., pictures depicting companionship during physical activities) and accompanying slogans have on motivating physical activity have been largely unexplored. Hence, our two studies experimentally tested the effects of exposure to affiliation-based pictures for overweight or less active people, as well as the moderating effect of affiliation motivation. The results of these two studies give some indication that group pictures (with or without an accompanying slogan) can be an effective strategy to improve high-risk populations' attitudes, self-efficacy, and intentions to engage in physical activity. Affiliation motivation as a personality trait did not interact with these effects, but was positively associated with attitudes, independent of the group picture effect.
Spatial Patterns of High Aedes aegypti Oviposition Activity in Northwestern Argentina
Estallo, Elizabet Lilia; Más, Guillermo; Vergara-Cid, Carolina; Lanfri, Mario Alberto; Ludueña-Almeida, Francisco; Scavuzzo, Carlos Marcelo; Introini, María Virginia; Zaidenberg, Mario; Almirón, Walter Ricardo
2013-01-01
Background In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. Methodology Oviposition activity was detected in Orán City (Salta province) using ovitraps, weekly replaced (October 2005–2007). Spatial autocorrelation was measured with Moran’s Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR) sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. Principal Findings Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC = 0.77), obtaining 99% of sensitivity and 75.29% of specificity. Conclusions Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist National Health Ministry to focus resources more effectively. PMID:23349813
The Respiratory System and Diazotrophic Activity of Acetobacter diazotrophicus PAL5
Flores-Encarnación, M.; Contreras-Zentella, M.; Soto-Urzua, L.; Aguilar, G. R.; Baca, B. E.; Escamilla, J. E.
1999-01-01
The characteristics of the respiratory system of Acetobacter diazotrophicus PAL5 were investigated. Increasing aeration (from 0.5 to 4.0 liters of air min−1 liter of medium−1) had a strong positive effect on growth and on the diazotrophic activity of cultures. Cells obtained from well-aerated and diazotrophically active cultures possessed a highly active, membrane-bound electron transport system with dehydrogenases for NADH, glucose, and acetaldehyde as the main electron donors. Ethanol, succinate, and gluconate were also oxidized but to only a minor extent. Terminal cytochrome c oxidase-type activity was poor as measured by reduced N,N,N,N′-tetramethyl-p-phenylenediamine, but quinol oxidase-type activity, as measured by 2,3,5,6-tetrachloro-1,4-benzenediol, was high. Spectral and high-pressure liquid chromatography analysis of membranes revealed the presence of cytochrome ba as a putative oxidase in cells obtained from diazotrophically active cultures. Cells were also rich in c-type cytochromes; four bands of high molecular mass (i.e., 67, 56, 52, and 45 kDa) were revealed by a peroxidase activity stain in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. KCN inhibition curves of respiratory oxidase activities were biphasic, with a highly resistant component. Treatment of membranes with 0.2% Triton X-100 solubilized c-type cytochromes and resulted in a preparation that was significantly more sensitive to cyanide. Repression of diazotrophic activity in well-aerated cultures by 40 mM (NH4)2SO4 caused a significant decrease of the respiratory activities. It is noteworthy that the levels of glucose dehydrogenase and putative oxidase ba decreased 6.8- and 10-fold, respectively. In these cells, a bd-type cytochrome seems to be the major terminal oxidase. Thus, it would seem that glucose dehydrogenase and cytochrome ba are key components of the respiratory system of A. diazotrophicus during aerobic diazotrophy. PMID:10559164
Koolhaas, Chantal M; Dhana, Klodian; Schoufour, Josje D; Ikram, M Arfan; Kavousi, Maryam; Franco, Oscar H
2017-06-01
Background Being overweight or obese is associated with an increased risk of cardiovascular disease (CVD). Physical activity might reduce the risk associated with overweight and obesity. We examined the association between overweight and obesity and CVD risk as a function of physical activity levels in a middle-aged and elderly population. Design The study was a prospective cohort study. Methods The study included 5344 participants aged 55 years or older from the population-based Rotterdam Study. Participants were classified as having high or low physical activity based on the median of the population. Normal weight (18.5-24.9 kg/m 2 ), overweight (25.0-29.9 kg/m 2 ) and obese participants (≥30 kg/m 2 ) were categorized as having high or low physical activity to form six categories. We assessed the association of the six categories with CVD risk using Cox proportional hazard models adjusted for confounders. High physical activity and normal weight was used as the reference group. Results During 15 years of follow-up (median 10.3 years, interquartile range 8.2-11.7 years), 866 (16.2%) participants experienced a CVD event. Overweight and obese participants with low physical activity had a higher CVD risk than normal weight participants with high physical activity. The HRs and 95% confidence intervals (CIs) were 1.33 (1.07-1.66) and 1.35 (1.04-1.75), respectively. Overweight and obese participants with high physical activity did not show a higher CVD risk (HRs (95%CIs) 1.03 (0.82-1.29) and 1.12 (0.83-1.52), respectively). Conclusions Our findings suggest that the beneficial impact of physical activity on CVD might outweigh the negative impact of body mass index among middle-aged and elderly people. This emphasizes the importance of physical activity for everyone across all body mass index strata, while highlighting the risk associated with inactivity even among normal weight people.
Frau, Lucia; Simola, Nicola; Porceddu, Pier Francesca; Morelli, Micaela
2016-09-01
3,4-methylenedyoxymethamphetamine (MDMA or "ecstasy"), a recreational drug of abuse, can induce glia activation and dopaminergic neurotoxicity. Since MDMA is often consumed in crowded environments featuring high temperatures, we studied how these factors influenced glia activation and dopaminergic neurotoxicity induced by MDMA. C57BL/6J adolescent (4 weeks old) and adult (12 weeks old) mice received MDMA (4×20mg/kg) in different conditions: 1) while kept 1, 5, or 10×cage at room temperature (21°C); 2) while kept 5×cage at either room (21°C) or high (27°C) temperature. After the last MDMA administration, immunohistochemistry was performed in the caudate-putamen for CD11b and GFAP, to mark microglia and astroglia, and in the substantia nigra pars compacta for tyrosine hydroxylase, to mark dopaminergic neurons. MDMA induced glia activation and dopaminergic neurotoxicity, compared with vehicle administration. Crowding (5 or 10 mice×cage) amplified MDMA-induced glia activation (in adult and adolescent mice) and dopaminergic neurotoxicity (in adolescent mice). Conversely, exposure to a high environmental temperature (27°C) potentiated MDMA-induced glia activation in adult and adolescent mice kept 5×cage, but not dopaminergic neurotoxicity. Crowding and exposure to a high environmental temperature amplified MDMA-induced hyperthermia, and a positive correlation between body temperature and activation of either microglia or astroglia was found in adult and adolescent mice. These results provide further evidence that the administration setting influences the noxious effects of MDMA in the mouse brain. However, while crowding amplifies both glia activation and dopaminergic neurotoxicity, a high environmental temperature exacerbates glia activation only. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Lee, Ki Bang
2006-11-01
Two-step activation of paper batteries has been successfully demonstrated to provide quick activation and to supply high power to credit card-sized biosystems on a plastic chip. A stack of a magnesium layer (an anode), a fluid guide (absorbent paper), a highly doped filter paper with copper chloride (a cathode) and a copper layer as a current collector is laminated between two transparent plastic films into a high power biofluid- and water-activated battery. The battery is activated by two-step activation: (1) after placing a drop of biofluid/water-based solution on the fluid inlet, the surface tension first drives the fluid to soak the fluid guide; (2) the fluid in the fluid guide then penetrates into the heavily doped filter paper with copper chloride to start the battery reaction. The fabricated half credit card-sized battery was activated by saliva, urine and tap water and delivered a maximum voltage of 1.56 V within 10 s after activation and a maximum power of 15.6 mW. When 10 kΩ and 1 KΩ loads are used, the service time with water, urine and saliva is measured as more than 2 h. An in-series battery of 3 V has been successfully tested to power two LEDs (light emitting diodes) and an electric driving circuit. As such, this high power paper battery could be integrated with on-demand credit card-sized biosystems such as healthcare test kits, biochips, lab-on-a-chip, DNA chips, protein chips or even test chips for water quality checking or chemical checking.
Jonefjäll, Börje; Simrén, Magnus; Lasson, Anders; Öhman, Lena; Strid, Hans
2017-01-01
Background Patients with ulcerative colitis often report fatigue. Objectives To investigate prevalence of and risk factors for fatigue in patients with ulcerative colitis with active disease and during deep remission. Methods In this cross-sectional study, disease activity was evaluated with endoscopy and calprotectin, and patients were classified as having active disease (n = 133) or being in deep remission (n = 155). Blood samples were analysed to assess anaemia, iron deficiency and systemic immune activity. Patients completed questionnaires to assess fatigue, psychological distress, gastrointestinal symptoms and quality of life. Results The prevalence of high fatigue (general fatigue ≥ 13, Multidimensional Fatigue Inventory) was 40% in the full study population. Among patients with high fatigue, female gender and iron deficiency were more prevalent, and these patients had more severe disease activity and reported higher levels of anxiety, depression and decreased quality of life compared with patients with no/mild fatigue. A logistic regression analysis identified probable psychiatric disorder (odds ratio (OR) (confidence interval) 6.1 (3.1–12.2)), iron deficiency (OR 2.5 (1.2–5.1)), active disease (OR 2.2 (1.2–3.9)) and female gender (OR 2.1 (1.1–3.7)) as independent risk factors for high fatigue. Similar results were found concerning psychological distress, gender and quality of life, but immune markers did not differ in patients in deep remission with high vs. no/mild fatigue. Conclusions Probable psychiatric disorder, iron deficiency, active disease and female gender are independent risk factors for high fatigue in patients with ulcerative colitis. Low-grade immune activity does not seem to be the cause of fatigue among patients in deep remission. PMID:29435325
Theory-based physical activity beliefs by race and activity levels among older adults.
Kosma, Maria; Cardinal, Bradley J
2016-01-01
Given the benefits of physical activity and the high proportion of inactivity among older adults, the purpose was to elicit theory-based behavioral, normative, and control physical activity beliefs among 140 educationally and economically diverse older adults and compare their beliefs by race (Blacks vs. Whites) and physical activity levels (inactive/underactive vs. highly active individuals). This was an elicitation study that took place in eight, mostly rural community settings in a Southeastern US state, such as Council of Aging Offices, retirement centers, and churches. Participants' behavioral, normative, and control beliefs were elicited via in person interviews. A valid and reliable questionnaire was also used to assess their physical activity levels. According to the content analysis, inactive/underactive participants reported fewer physical activity advantages than highly active participants. Common physical activity advantages between the two groups were overall health, emotional functioning, and physical functioning. Similar physical activity advantages were reported among Blacks and Whites with overall health being the most important advantage. The most common physical activity disadvantages and barriers for all four groups were falls, injuries, pain, and health issues. Inactive/underactive individuals and Blacks tended to report more disadvantages and barriers than their peers. Common physical activity supporters were family members, friends and peers, and health-care professionals. In their physical activity motivational programs, health promoters should reinforce physical activity benefits, social support, access to activity programs, and safety when intervening among older adults.
Extreme Pregnancy: Maternal Physical Activity at Everest Base Camp.
Davenport, Margie H; Steinback, Craig D; Borle, Kennedy J; Matenchuk, Brittany A; Vanden Berg, Emily R; de Freitas, Emily M; Linares, Andrea M; O'Halloran, Ken D; Sherpa, Mingma T; Day, Trevor A
2018-05-10
High altitude natives employ numerous physiological strategies to survive and reproduce. However, the concomitant influence of altitude and physical activity during pregnancy has not been studied above 3,700m. We report a case of physical activity, sleep behavior and physiological measurements on a 28-year-old third-trimester pregnant native highlander (Sherpa) during ascent from 3440m to Everest base camp (~5,300m) over eight days in the Nepal Himalaya, and again ~10-months postpartum during a similar ascent profile. The participant engaged in 250-300 minutes of moderate-to-vigorous physical activity (MVPA) per day during ascent to altitude while pregnant, with similar volumes of MVPA while postpartum. There were no apparent maternal, fetal or neonatal complications related to the superimposition of the large volumes of physical activity at altitude. This report demonstrates a rare description of physical activity and ascent to high altitude during pregnancy and points to novel questions regarding the superimposition of pregnancy, altitude and physical activity in high altitude natives.
NASA Astrophysics Data System (ADS)
Wang, Haoren; Wang, Hui; Li, Xiuyi; Li, Chunyi
2017-06-01
Different with Wang et. al.'s study, we found that polymeric Si-O-Sn2+ rather than Ni-Sn alloy and metallic Sn are active species in silica-supported tin oxide catalysts for dehydrogenation of propane. The results showed that high surface area of mesoporous silica brought about high dispersion of tin oxide species, as a result, catalytic activity and stability were both improved. DRUV-vis, XPS, TPR and XRD studies of fresh and reduced catalysts indicated that the deactivation was related to the reduction of active species rather than the coke formation since active tin species cannot maintain its oxidation state at reaction conditions (high temperature and reducing atmosphere). The formed Ni3Sn2 alloy after reduction just functioned as promoter which accelerated the desorption of H2 and regeneration of active site. A synergy effect between active tin species and Ni3Sn2 alloy were observed.
High-Fat Diets Alter the Modulatory Effects of Xenobiotics on Cytochrome P450 Activities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sadler, Natalie C.; Webb-Robertson, Bobbie-Jo M.; Clauss, Therese R.
Cytochrome P450 monooxygenases (P450) are key to the metabolism of myriad endogenous chemicals and xenobiotics, including the majority of therapeutic drugs. Dysregulated P450 activities can lead to altered drug metabolism and toxicity, oxidative stress, and inflammation; all physiological states frequently charged as the impetus for various chronic pathologies. We characterized the impact of common xenobiotic exposures, specifically high-fat diet and active or passive cigarette smoke, on the functional capacity of hepatic and pulmonary P450s. We employed an activity-based protein profiling approach to characterize the identity and activity level of measured individual P450 isoforms. Our results confirm expectations of significant alterationsmore » in pulmonary P450s due to cigarette smoke, but now reveal the repressive impact of high-fat diet-induced obesity on many hepatic P450s activities, and the dynamic alterations due to concomitant diet and smoke exposures on liver and lung P450 activities impacting drug metabolism and pathways of inflammation.« less
Beynen, A C; Weinans, G J; Katan, M B
1984-01-01
Arylesterase activities were measured with beta-naphthylpropionate and/or alpha-naphthylacetate as substrate in the plasma of rats, rabbits and humans on low- and high-cholesterol diets. The plasma esterase activities measured with alpha-naphthylacetate were similar in rats, rabbits and humans. With beta-naphthylpropionate as a substrate, rabbits were found to have a markedly higher esterase activity than rats and humans. Basal plasma esterase activity was significantly higher in an inbred rat strain which is hyporesponsive to dietary cholesterol than in a hyperresponsive strain. In rats, but not in humans and rabbits, plasma esterase activity was significantly increased by a high-cholesterol diet. In individual humans and random-bred rabbits and rats there was no association between initial plasma total esterase activity and the subsequent plasma cholesterol response to cholesterol feeding. We suggest that arylesterases are associated with cholesterol metabolism and with the response to dietary cholesterol in rats; evidence for such a role in rabbits and humans is, however, inconclusive.
On the asynchronization of hemispheric high-latitude solar activity
NASA Astrophysics Data System (ADS)
Li, K. J.; Gao, P. X.; Zhan, L. S.; Shi, X. J.; Zhu, W. W.
2008-11-01
The monthly mean numbers of polar faculae in the time interval of 1951 August to 1998 December, from observations of the National Astronomical Observatory of Japan are used to investigate the reasons which mathematically result in the asynchronization of high-latitude solar activity between the northern and southern hemispheres. It is found that the monthly mean numbers of polar faculae in the northern hemisphere three months lead those in the southern one, which should mathematically lead to phase asynchrony of the hemispheric polar-facula activity but with a slight effect. The Schwabe period length for the polar-facula activity in one hemisphere obviously differs from that in the other, which should also lead to phase asynchrony of the hemispheric polar-facula activity. It is the low-frequency components of the hemispheric polar-facula activity in period scales around the Schwabe cycle that are responsible for its strong phase synchronization. In the high-frequency components, there is a strong phase mixing, which should also lead to phase asynchrony of the hemispheric polar-facula activity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Jie; Zeng, Zhi; Wu, Teng
The activation of nuclear factor-κB (NF-κB) and the subsequent overexpression of its downstream targets transforming growth factor-β1 (TGF-β1) and fibronectin (FN) are among the hallmarks for the progressive diabetic nephropathy. Our previous studies demonstrated that emodin ameliorated renal injury and inhibited extracellular matrix accumulation in kidney and mesangial cells under diabetic condition. However, the molecular mechanism has not been fully elucidated. Here, we showed that emodin significantly attenuated high glucose-induced NF-κB nuclear translocation in mesangial cells. Interestingly, emodin also inhibited the DNA-binding activity and transcriptional activity of NF-κB. Furthermore, NF-κB-mediated TGF-β1 and FN expression was significantly decreased by emodin. Thesemore » results demonstrated that emodin suppressed TGF-β1 and FN overexpression through inhibition of NF-κB activation, suggesting that emodin-mediated inhibition of the NF-κB pathway could protect against diabetic nephropathy. - Highlights: • Emodin decreased high glucose-induced p65 phosphorylation in MCs. • Emodin decreased high glucose-induced IκB-α degradation in MCs. • Emodin decreased high glucose-induced p65 translocation in MCs. • Emodin blocked high glucose-induced NF-κB activity. • Emodin blocked high glucose-induced the expression of TGF-β1 and FN.« less
NASA Astrophysics Data System (ADS)
Muller, Leah; Rolston, John D.; Fox, Neal P.; Knowlton, Robert; Rao, Vikram R.; Chang, Edward F.
2018-04-01
Objective. Direct electrical stimulation (DES) is a clinical gold standard for human brain mapping and readily evokes conscious percepts, yet the neurophysiological changes underlying these percepts are not well understood. Approach. To determine the neural correlates of DES, we stimulated the somatosensory cortex of ten human participants at frequency-amplitude combinations that both elicited and failed to elicit conscious percepts, meanwhile recording neural activity directly surrounding the stimulation site. We then compared the neural activity of perceived trials to that of non-perceived trials. Main results. We found that stimulation evokes distributed high gamma activity, which correlates with conscious perception better than stimulation parameters themselves. Significance. Our findings suggest that high gamma activity is a reliable biomarker for perception evoked by both natural and electrical stimuli.
Yoshida, Eriko; Terada, Shin-Ichiro; Tanaka, Yasuyo H; Kobayashi, Kenta; Ohkura, Masamichi; Nakai, Junichi; Matsuzaki, Masanori
2018-05-29
In vivo wide-field imaging of neural activity with a high spatio-temporal resolution is a challenge in modern neuroscience. Although two-photon imaging is very powerful, high-speed imaging of the activity of individual synapses is mostly limited to a field of approximately 200 µm on a side. Wide-field one-photon epifluorescence imaging can reveal neuronal activity over a field of ≥1 mm 2 at a high speed, but is not able to resolve a single synapse. Here, to achieve a high spatio-temporal resolution, we combine an 8 K ultra-high-definition camera with spinning-disk one-photon confocal microscopy. This combination allowed us to image a 1 mm 2 field with a pixel resolution of 0.21 µm at 60 fps. When we imaged motor cortical layer 1 in a behaving head-restrained mouse, calcium transients were detected in presynaptic boutons of thalamocortical axons sparsely labeled with GCaMP6s, although their density was lower than when two-photon imaging was used. The effects of out-of-focus fluorescence changes on calcium transients in individual boutons appeared minimal. Axonal boutons with highly correlated activity were detected over the 1 mm 2 field, and were probably distributed on multiple axonal arbors originating from the same thalamic neuron. This new microscopy with an 8 K ultra-high-definition camera should serve to clarify the activity and plasticity of widely distributed cortical synapses.
Kefala, Maria; Kottaridi, Christine; Spathis, Aris; Gouloumi, Alina-Roxani; Pouliakis, Abraham; Pappas, Asimakis; Sioulas, Vasileios; Chrelias, Charalambos; Karakitsos, Petros; Panayiotides, Ioannis
2017-01-01
Background γH2AX is a protein biomarker for double-stranded DNA breakage; its expression was studied in cervical squamous intraepithelial lesions and carcinomas. Methods Immunostaining for phospho-γH2AX was performed in sections from histologically confirmed cervical SIL and carcinomas, as well as from normal cervices used as controls. In total, 275 cases were included in the study: 112 low grade SIL (LGSIL), 99 high grade SIL (HGSIL), 24 squamous cell carcinoma (SCC), 12 adenocarcinoma and 28 cervical specimens with no essential lesions. Correlation of histological grading, high risk vs. low risk HPV virus presence, activated vs. non-activated status (by high risk HPV mRNA expression) and γH2AX expression in both basal and surface segments of the squamous epithelium was performed. Results Gradual increase of both basal and surface γH2AX expression was noted up from normal cervices to LGSIL harboring a low risk HPV type, to LGSIL harboring a high risk virus at a non-activated state (p<0.05). Thereafter, both basal and surface γH2AX expression dropped in LGSIL harboring a high risk virus at an activated state and in HGSIL. Conclusions γH2AX could serve as a potential biomarker discriminating between LGSIL and HGSIL, as well as between LGSIL harboring high risk HPV at an activated state. PMID:28118377
Batukhtina, E I; Nevidimova, T I; Vetlugina, T P; Kokorina, N P; Bokhan, N A
2014-03-01
The correlation between search and creative behavior with parameters of bioelectric brain activity was observed in patients with addictive disorders. The prevalence of α- and θ-activities in the parietal-temporal-occipital areas of the cortex and increased θ-activity in the right hemisphere in addiction patients with high search and creative activities were associated with enhanced high-frequency activity in these brain areas. These changes can reflect the formation of a focus of pathologically increased excitation related to the pathogenic mechanisms of addictive disorders.
Fructose, Glucocorticoids and Adipose Tissue: Implications for the Metabolic Syndrome.
Legeza, Balázs; Marcolongo, Paola; Gamberucci, Alessandra; Varga, Viola; Bánhegyi, Gábor; Benedetti, Angiolo; Odermatt, Alex
2017-04-26
The modern Western society lifestyle is characterized by a hyperenergetic, high sugar containing food intake. Sugar intake increased dramatically during the last few decades, due to the excessive consumption of high-sugar drinks and high-fructose corn syrup. Current evidence suggests that high fructose intake when combined with overeating and adiposity promotes adverse metabolic health effects including dyslipidemia, insulin resistance, type II diabetes, and inflammation. Similarly, elevated glucocorticoid levels, especially the enhanced generation of active glucocorticoids in the adipose tissue due to increased 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activity, have been associated with metabolic diseases. Moreover, recent evidence suggests that fructose stimulates the 11β-HSD1-mediated glucocorticoid activation by enhancing the availability of its cofactor NADPH. In adipocytes, fructose was found to stimulate 11β-HSD1 expression and activity, thereby promoting the adipogenic effects of glucocorticoids. This article aims to highlight the interconnections between overwhelmed fructose metabolism, intracellular glucocorticoid activation in adipose tissue, and their metabolic effects on the progression of the metabolic syndrome.
Shima, S; Hérault, D A; Berkessel, A; Thauer, R K
1998-11-01
Enzymes involved in methane formation from carbon dioxide and dihydrogen in Methanopyrus kandleri require high concentrations (> 1 M) of lyotropic salts such as K2HPO4/KH2PO4 or (NH4)2SO4 for activity and for thermostability. The requirement correlates with high intracellular concentrations of cyclic 2,3-diphosphoglycerate (cDPG; approximately 1 M) in this hyperthermophilic organism. We report here on the effects of potassium cDPG on the activity and thermostability of the two methanogenic enzymes cyclohydrolase and formyltransferase and show that at cDPG concentrations prevailing in the cells the investigated enzymes are highly active and completely thermostable. At molar concentrations also the potassium salts of phosphate and of 2,3-bisphosphoglycerate, the biosynthetic precursor of cDPG, were found to confer activity and thermostability to the enzymes. Thermodynamic arguments are discussed as to why cDPG, rather than these salts, is present in high concentrations in the cells of Mp. kandleri.
Fructose, Glucocorticoids and Adipose Tissue: Implications for the Metabolic Syndrome
Legeza, Balázs; Marcolongo, Paola; Gamberucci, Alessandra; Varga, Viola; Bánhegyi, Gábor; Benedetti, Angiolo; Odermatt, Alex
2017-01-01
The modern Western society lifestyle is characterized by a hyperenergetic, high sugar containing food intake. Sugar intake increased dramatically during the last few decades, due to the excessive consumption of high-sugar drinks and high-fructose corn syrup. Current evidence suggests that high fructose intake when combined with overeating and adiposity promotes adverse metabolic health effects including dyslipidemia, insulin resistance, type II diabetes, and inflammation. Similarly, elevated glucocorticoid levels, especially the enhanced generation of active glucocorticoids in the adipose tissue due to increased 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activity, have been associated with metabolic diseases. Moreover, recent evidence suggests that fructose stimulates the 11β-HSD1-mediated glucocorticoid activation by enhancing the availability of its cofactor NADPH. In adipocytes, fructose was found to stimulate 11β-HSD1 expression and activity, thereby promoting the adipogenic effects of glucocorticoids. This article aims to highlight the interconnections between overwhelmed fructose metabolism, intracellular glucocorticoid activation in adipose tissue, and their metabolic effects on the progression of the metabolic syndrome. PMID:28445389
High-throughput screening of filamentous fungi using nanoliter-range droplet-based microfluidics
NASA Astrophysics Data System (ADS)
Beneyton, Thomas; Wijaya, I. Putu Mahendra; Postros, Prexilia; Najah, Majdi; Leblond, Pascal; Couvent, Angélique; Mayot, Estelle; Griffiths, Andrew D.; Drevelle, Antoine
2016-06-01
Filamentous fungi are an extremely important source of industrial enzymes because of their capacity to secrete large quantities of proteins. Currently, functional screening of fungi is associated with low throughput and high costs, which severely limits the discovery of novel enzymatic activities and better production strains. Here, we describe a nanoliter-range droplet-based microfluidic system specially adapted for the high-throughput sceening (HTS) of large filamentous fungi libraries for secreted enzyme activities. The platform allowed (i) compartmentalization of single spores in ~10 nl droplets, (ii) germination and mycelium growth and (iii) high-throughput sorting of fungi based on enzymatic activity. A 104 clone UV-mutated library of Aspergillus niger was screened based on α-amylase activity in just 90 minutes. Active clones were enriched 196-fold after a single round of microfluidic HTS. The platform is a powerful tool for the development of new production strains with low cost, space and time footprint and should bring enormous benefit for improving the viability of biotechnological processes.
BILAG-2004 index captures systemic lupus erythematosus disease activity better than SLEDAI-2000.
Yee, C-S; Isenberg, D A; Prabu, A; Sokoll, K; Teh, L-S; Rahman, A; Bruce, I N; Griffiths, B; Akil, M; McHugh, N; D'Cruz, D; Khamashta, M A; Maddison, P; Zoma, A; Gordon, C
2008-06-01
To assess the reliability of Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)-2000 index in routine practice and its ability to capture disease activity as compared with the British Isles Lupus Assessment Group (BILAG)-2004 index. Patients with systemic lupus erythematosus from 11 centres were assessed separately by two raters in routine practice. Disease activity was assessed using the BILAG-2004 and SLEDAI-2000 indices. The level of agreement for items was used to assess the reliability of SLEDAI-2000. The ability to detect disease activity was assessed by determining the number of patients with a high activity on BILAG-2004 (overall score A or B) but low SLEDAI-2000 score (<6) and number of patients with low activity on BILAG-2004 (overall score C, D or E) but high SLEDAI-2000 score (>or=6). Treatment of these patients was analysed, and the increase in treatment was used as the gold standard for active disease. 93 patients (90.3% women, 69.9% Caucasian) were studied: mean age was 43.8 years, mean disease duration 10 years. There were 43 patients (46.2%) with a difference in SLEDAI-2000 score between the two raters and this difference was >or=4 in 19 patients (20.4%). Agreement for each of the items in SLEDAI-2000 was between 81.7 and 100%. 35 patients (37.6%) had high activity on BILAG-2004 but a low SLEDAI-2000 score, of which 48.6% had treatment increased. There were only five patients (5.4%) with low activity on BILAG-2004 but a high SLEDAI-2000 score. SLEDAI-2000 is a reliable index to assess systemic lupus erythematosus disease activity but it is less able than the BILAG-2004 index to detect active disease requiring increased treatment.
Goals and intentions mediate efficacy beliefs and declining physical activity in high school girls.
Dishman, Rod K; Saunders, Ruth P; Felton, Gwen; Ward, Dianne S; Dowda, Marsha; Pate, Russ R
2006-12-01
According to theory, girls who set goals about increasing their physical activity and who are dissatisfied with their current activity level are likely to form intentions to be active and to carry out those intentions, especially if they have high efficacy and control beliefs about being physically active. We tested those ideas while observing naturally occurring change during high school. A cohort of 431 black and white girls was tested at the end of their 9th- and 12th-grade academic years. Confirmatory factor analysis established the structural invariance of the measures across the 3-year study period. Structural equation modeling and panel analysis were used to determine whether changes in goal setting and satisfaction would mediate relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. Testing occurred between February and May in 1999 and 2004. Data were analyzed in 2006. Goal setting and intention mediated the indirect relation between self-efficacy and change in physical activity. Perceived behavioral control and physical activity change were related directly and also indirectly by a path mediated through satisfaction and intention. Black girls had lower self-efficacy, but changes in other variables were unrelated to race. These observations of longitudinal relations elaborate application of self-efficacy theory and the theory of planned behavior to physical activity by showing that goal setting and satisfaction mediate the relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. The results encourage additional research to identify the sources and development of physical activity goals, and their attainment, among girls, and whether experimental manipulation of goals and intentions can mitigate the decline in girls' physical activity during high school.
Sherwood, Nancy E; Story, Mary; Neumark-Sztainer, Dianne; Adkins, Sarah; Davis, Marsha
2003-11-01
Card-sorting tasks for assessing food and activity preferences and patterns among African American girls were developed. Associations among food preference and intake frequency, activity preference and frequency, and body mass index were examined. Participants completed newly developed card-sorting tasks assessing food and activity preferences and patterns. Height and weight were measured. Ninety-six 8- to 10-year-old African American girls from schools and community centers in Minneapolis-St. Paul. Preference and frequency data for 64 foods/beverages and 34 activities. Frequencies for food and activity preference and frequency categories were computed. Pearson correlations among food and activity preference, frequency, and body mass index were computed. High-sugar (eg, fruit drinks, soda) and/or high-fat (eg, ice cream, cookies) foods were among the most popular and frequently consumed. Ninety-six percent of girls liked fruit drinks, with 35% consuming them "almost every day." Less-structured activities such as biking, games, jump rope, and dance were most popular. Biking was preferred by 85% of girls, with 48% biking "almost every day." Food preference and frequency categories were moderately correlated (r=0.30 to 0.58), as were activity preference and frequency (r=0.37 to 0.49). The card-sorting tasks are useful tools for assessing food and activity preferences and patterns in girls. Obesity prevention programs for African American girls should include preferred activities such as dance, jump rope, and active play. Programs may also benefit from a focus on replacing high fat/high sugar snacks and sweetened beverages with low-fat, lower-calorie snacks and beverages (eg, fruit, vegetables, water).
Berkowitz, Judy M; Huhman, Marian; Nolin, Mary Jo
2008-06-01
Although VERB was designed as a national media campaign, funding and donated media time enabled more-intensive advertising and marketing in certain communities. To investigate the effect of increased advertising on physical activity outcomes, six "high-dose" communities were selected to receive more hours of advertising and additional promotional activities. Longitudinal quasi-experimental design comparing outcomes in six communities that received additional VERB marketing activities with outcomes in a comparison group that received only the national dose of advertising. Two cohorts of dyads of youth aged 9-13 years (tweens) and one parent at baseline (2002), followed for 2 years. During the first year of the VERB campaign, each of the six high-dose communities received 50% more advertising and conducted special campaign activities. During the second year, only four of the six communities received the larger dose of advertising and additional promotional activities because of reduced funding. Awareness and understanding of VERB messages; attitudes about physical activity (self-efficacy, social influences, and outcome expectations); and physical activity behaviors. After 1 year, tweens in the high-dose communities reported higher levels of awareness and understanding of VERB and scored higher on the social influences scale than did tweens in a comparison group in areas that received only the national dose of advertising. After 2 years, tweens in the high-dose communities reported higher awareness and understanding of VERB, greater self-efficacy, more sessions of free-time physical activity per week, and were more active on the day before being surveyed than tweens in the comparison group who received the average national dose. Providing communities with a higher dose of marketing activities and sustaining those activities over time yields more positive outcomes.
Erickson, Darin J.; Rutledge, Patricia C.; Lenk, Kathleen M.; Nelson, Toben F.; Jones-Webb, Rhonda; Toomey, Traci L.
2015-01-01
Aims We assessed levels and patterns of alcohol policy enforcement activities among U.S. local law enforcement agencies. Design/Setting/Participants We conducted a cross-sectional survey of a representative sample of 1,631 local law enforcement agencies across the 50 states. Measures/Methods We assessed 29 alcohol policy enforcement activities within each of five enforcement domains—underage alcohol possession/consumption, underage alcohol provision, underage alcohol sales, impaired driving, and overservice of alcohol—and conducted a series of latent class analyses to identify unique classes or patterns of enforcement activity for each domain. Findings We identified three to four unique enforcement activity classes for each of the enforcement domains. In four of the domains, we identified a Uniformly Low class (i.e., little or no enforcement) and a Uniformly High enforcement activity class (i.e., relatively high levels of enforcement), with one or two middle classes where some but not all activities were conducted. The underage provision domain had a Uniformly Low class but not a Uniformly High class. The Uniformly Low class was the most prevalent class in three domains: underage provision (58%), underage sales (61%), and overservice (79%). In contrast, less than a quarter of agencies were in Uniformly High classes. Conclusions We identified qualitatively distinct patterns of enforcement activity, with a large proportion of agencies in classes characterized by little or no enforcement and fewer agencies in high enforcement classes. An important next step is to determine if these patterns are associated with rates of alcohol use and alcohol-related injury and mortality. PMID:26877822
Wetzels, Sandra A J; Kester, Liesbeth; van Merriënboer, Jeroen J G; Broers, Nick J
2011-06-01
Prior knowledge activation facilitates learning. Note taking during prior knowledge activation (i.e., note taking directed at retrieving information from memory) might facilitate the activation process by enabling learners to build an external representation of their prior knowledge. However, taking notes might be less effective in supporting prior knowledge activation if available prior knowledge is limited. This study investigates the effects of the retrieval-directed function of note taking depending on learners' level of prior knowledge. It is hypothesized that the effectiveness of note taking is influenced by the amount of prior knowledge learners already possess. Sixty-one high school students participated in this study. A prior knowledge test was used to ascertain differences in level of prior knowledge and assign participants to a low or a high prior knowledge group. A 2×2 factorial design was used to investigate the effects of note taking during prior knowledge activation (yes, no) depending on learners' level of prior knowledge (low, high) on mental effort, performance, and mental efficiency. Note taking during prior knowledge activation lowered mental effort and increased mental efficiency for high prior knowledge learners. For low prior knowledge learners, note taking had the opposite effect on mental effort and mental efficiency. The effects of the retrieval-directed function of note taking are influenced by learners' level of prior knowledge. Learners with high prior knowledge benefit from taking notes while activating prior knowledge, whereas note taking has no beneficial effects for learners with limited prior knowledge. ©2010 The British Psychological Society.
Cowley, Benjamin R.; Kaufman, Matthew T.; Butler, Zachary S.; Churchland, Mark M.; Ryu, Stephen I.; Shenoy, Krishna V.; Yu, Byron M.
2014-01-01
Objective Analyzing and interpreting the activity of a heterogeneous population of neurons can be challenging, especially as the number of neurons, experimental trials, and experimental conditions increases. One approach is to extract a set of latent variables that succinctly captures the prominent co-fluctuation patterns across the neural population. A key problem is that the number of latent variables needed to adequately describe the population activity is often greater than three, thereby preventing direct visualization of the latent space. By visualizing a small number of 2-d projections of the latent space or each latent variable individually, it is easy to miss salient features of the population activity. Approach To address this limitation, we developed a Matlab graphical user interface (called DataHigh) that allows the user to quickly and smoothly navigate through a continuum of different 2-d projections of the latent space. We also implemented a suite of additional visualization tools (including playing out population activity timecourses as a movie and displaying summary statistics, such as covariance ellipses and average timecourses) and an optional tool for performing dimensionality reduction. Main results To demonstrate the utility and versatility of DataHigh, we used it to analyze single-trial spike count and single-trial timecourse population activity recorded using a multi-electrode array, as well as trial-averaged population activity recorded using single electrodes. Significance DataHigh was developed to fulfill a need for visualization in exploratory neural data analysis, which can provide intuition that is critical for building scientific hypotheses and models of population activity. PMID:24216250
NASA Astrophysics Data System (ADS)
Cowley, Benjamin R.; Kaufman, Matthew T.; Butler, Zachary S.; Churchland, Mark M.; Ryu, Stephen I.; Shenoy, Krishna V.; Yu, Byron M.
2013-12-01
Objective. Analyzing and interpreting the activity of a heterogeneous population of neurons can be challenging, especially as the number of neurons, experimental trials, and experimental conditions increases. One approach is to extract a set of latent variables that succinctly captures the prominent co-fluctuation patterns across the neural population. A key problem is that the number of latent variables needed to adequately describe the population activity is often greater than 3, thereby preventing direct visualization of the latent space. By visualizing a small number of 2-d projections of the latent space or each latent variable individually, it is easy to miss salient features of the population activity. Approach. To address this limitation, we developed a Matlab graphical user interface (called DataHigh) that allows the user to quickly and smoothly navigate through a continuum of different 2-d projections of the latent space. We also implemented a suite of additional visualization tools (including playing out population activity timecourses as a movie and displaying summary statistics, such as covariance ellipses and average timecourses) and an optional tool for performing dimensionality reduction. Main results. To demonstrate the utility and versatility of DataHigh, we used it to analyze single-trial spike count and single-trial timecourse population activity recorded using a multi-electrode array, as well as trial-averaged population activity recorded using single electrodes. Significance. DataHigh was developed to fulfil a need for visualization in exploratory neural data analysis, which can provide intuition that is critical for building scientific hypotheses and models of population activity.
Akazawa, Kazuki; Sugihara, Fuminori; Nakamura, Tatsuya; Mizukami, Shin; Kikuchi, Kazuya
2018-05-16
Highly sensitive imaging of enzymatic activities in the deep tissues of living mammals provides useful information about their biological functions and for developing new drugs; however, such imaging is challenging. 19 F magnetic resonance imaging (MRI) is suitable for noninvasive visualization of enzymatic activities without endogenous background signals. Although various enzyme-responsive 19 F MRI probes have been developed, most cannot be used for in vivo imaging because of their low sensitivity. Recently, we developed unique nanoparticles, called FLAMEs, that are composed of a liquid perfluorocarbon core and a robust silica shell, and demonstrated their outstanding sensitivity in vivo. Here, we report a highly functionalized nanoprobe, FLAME-DEVD 2, with an OFF/ON 19 F MRI switch for detecting caspase-3/7 activity based on the paramagnetic relaxation enhancement effect. To improve the cleavage efficiency of peptides by caspase-3, we designed a novel Gd 3+ complex-conjugated peptide, DEVD X ( X = 1, 2), which is a substrate peptide sequence tandemly repeated X times, and demonstrated that DEVD 2 showed faster cleavage kinetics than DEVD 1. By incorporating this novel concept into a signal activation strategy, FLAME-DEVD 2 showed a high 19 F MRI signal enhancement rate in response to caspase-3 activity. After intravenous injection of FLAME-DEVD 2 and an apoptosis-inducing reagent, caspase-3/7 activity in the spleen of a living mouse was successfully imaged by 19 F MRI. This imaging platform shows great potential for highly sensitive detection of enzymatic activities in vivo.
Cowley, Benjamin R; Kaufman, Matthew T; Butler, Zachary S; Churchland, Mark M; Ryu, Stephen I; Shenoy, Krishna V; Yu, Byron M
2013-12-01
Analyzing and interpreting the activity of a heterogeneous population of neurons can be challenging, especially as the number of neurons, experimental trials, and experimental conditions increases. One approach is to extract a set of latent variables that succinctly captures the prominent co-fluctuation patterns across the neural population. A key problem is that the number of latent variables needed to adequately describe the population activity is often greater than 3, thereby preventing direct visualization of the latent space. By visualizing a small number of 2-d projections of the latent space or each latent variable individually, it is easy to miss salient features of the population activity. To address this limitation, we developed a Matlab graphical user interface (called DataHigh) that allows the user to quickly and smoothly navigate through a continuum of different 2-d projections of the latent space. We also implemented a suite of additional visualization tools (including playing out population activity timecourses as a movie and displaying summary statistics, such as covariance ellipses and average timecourses) and an optional tool for performing dimensionality reduction. To demonstrate the utility and versatility of DataHigh, we used it to analyze single-trial spike count and single-trial timecourse population activity recorded using a multi-electrode array, as well as trial-averaged population activity recorded using single electrodes. DataHigh was developed to fulfil a need for visualization in exploratory neural data analysis, which can provide intuition that is critical for building scientific hypotheses and models of population activity.
Ahmed, Humeda S.; Khalid, Mohammed E. M.; Osman, Osama M.; Ballal, Mansour A.; Al-Hashem, Fahaid H.
2016-01-01
Objective: To assess the relationship between overweight and obesity and physical activity in Saudi children born and permanently domiciled at high and low altitudes in Southwestern Saudi Arabia. Subjects and Methods: A cross-sectional study of 145 healthy Saudi children aged 10–15 years who were born and lived permanently at high altitude (3000–3100 m) and 154 healthy Saudi children of comparable age who were born and lived permanently at a relatively low altitude (500 m) was conducted. For each subject selected, body weight and body height were measured using an Avery beam weighing scale and a stadiometer, respectively. Body mass index (BMI) was calculated using the equation BMI = (weight [kg]/height [m2]). Physical activity scores were determined using International Physical Activity Questionnaire-Short Form-A. Resting radial pulse rate (beat/minutes) was determined clinically. Results: Physical activity was significantly and inversely associated with overweight and obesity in boys at both high (χ2 = 15.8, P< 0.001) and low (χ2 = 14.7, P< 0.001) altitudes, but there was no clear trend for girls at either altitude. The lack of association between physical activity and overweight and obesity in girls was attributed to the low and homogeneous level of physical activity. Conclusion: Physical activity should be encouraged as a strategy for weight reduction in the overweight and the obese and the prevention of overweight and obesity in Saudi children at high and low altitudes. PMID:27186153
High repetition rate, high energy, actively Q-switched all-in-fiber laser
NASA Astrophysics Data System (ADS)
Lecourt, J. B.; Bertrand, A.; Guillemet, S.; Hernandez, Y.; Giannone, D.
2010-05-01
We report an actively Q-switched Ytterbium-doped all-in-fibre laser delivering 10ns pulses with high repetition rate (from 100kHz to 1MHz). The laser operation has been validated at three different wavelengths (1040, 1050 and 1064nm). The laser can deliver up to 20Watts average power with an high beam quality (M2 = 1).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Biaohua; He, Xiaobo; Yin, Fengxiang
A highly efficient bifunctional oxygen catalyst is required for practical applications of fuel cells and metal-air batteries, as oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are their core electrode reactions. Here, the MO-Co@ N-doped carbon (NC, M = Zn or Co) is developed as a highly active ORR/OER bifunctional catalyst via pyrolysis of a bimetal metal-organic framework containing Zn and Co, i.e., precursor (CoZn). The vital roles of inactive Zn in developing highly active bifunctional oxygen catalysts are unraveled. When the precursors include Zn, the surface contents of pyridinic N for ORR and the surface contents of Co-N-xmore » and Co3+/Co2+ ratios for OER are enhanced, while the high specific surface areas, high porosity, and high electrochemical active surface areas are also achieved. Furthermore, the synergistic effects between Zn-based and Co-based species can promote the well growth of multiwalled carbon nanotubes (MWCNTs) at high pyrolysis temperatures (>= 700 degrees C), which is favorable for charge transfer. The optimized CoZn-NC-700 shows the highly bifunctional ORR/OER activity and the excellent durability during the ORR/OER processes, even better than 20 wt% Pt/C (for ORR) and IrO2 (for OER). CoZn-NC-700 also exhibits the prominent Zn-air battery performance and even outperforms the mixture of 20 wt% Pt/C and IrO2.« less
Ma, Yanxia; Yin, Lisi; Cao, Guojian; Huang, Qingli; He, Maoshuai; Wei, Wenxian; Zhao, Hong; Zhang, Dongen; Wang, Mingyan; Yang, Tao
2018-04-01
Exploration of highly efficient electrocatalysts is significantly urgent for the extensive adoption of the fuel cells. Because of their high activity and super stability, Pt-Pd bimetal nanocrystals have been widely recognized as one class of promising electrocatalysts for oxygen reduction. This article presents the synthesis of popcorn-shaped Pt-Pd bimetal nanoparticles with a wide composition range through a facile hydrothermal strategy. The hollow-centered nanoparticles are surrounded by several petals and concave surfaces. By exploring the oxygen reduction reaction on the carbon supported Pt-Pd popcorns in perchloric acid solution, it is found that compared with the commercial Pt/C catalyst the present catalysts display superior catalytic performances in aspects of catalytic activity and stability. More importantly, the Pt-Pd popcorns display minor performance degradations through prolonged potential cycling. The enhanced performances can be mainly attributed to the unique popcorn structure of the Pt-Pd components, which allows the appearance and long existence of the high active sites with more accessibility. The present work highlights the key roles of accessible high active sites in the oxygen reduction reaction, which will ultimately guide the design of highly durable Pt-Pd catalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Suanarunsawat, Thamolwan; Devakul Na Ayutthaya, Watcharaporn; Songsak, Thanapat; Thirawarapan, Suwan; Poungshompoo, Somlak
2011-01-01
The present study was conducted to investigate the lipid-lowering and antioxidative activities of Ocimum sanctum L. (OS) leaf extracts in liver and heart of rats fed with high-cholesterol (HC) diet for seven weeks. The results shows that OS suppressed the high levels of serum lipid profile and hepatic lipid content without significant effects on fecal lipid excretion. Fecal bile acids excretion was increased in HC rats treated with OS. The high serum levels of TBARS as well as AST, ALT, AP, LDH, CK-MB significantly decreased in HC rats treated with OS. OS suppressed the high level of TABARS and raised the low activities of GPx and CAT without any impact on SOD in the liver. As for the cardiac tissues, OS lowered the high level of TABARS, and raised the activities of GPx, CAT, and SOD. Histopathological results show that OS preserved the liver and myocardial tissues. It can be concluded that OS leaf extracts decreased hepatic and serum lipid profile, and provided the liver and cardiac tissues with protection from hypercholesterolemia. The lipid-lowering effect is probably due to the rise of bile acids synthesis using cholesterol as precursor, and antioxidative activity to protect liver from hypercholesterolemia. PMID:21949899
Insights into the dominant factors of porous gold for CO oxidation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kameoka, Satoshi, E-mail: kameoka@tagen.tohoku.ac.jp; Miyamoto, Kanji; Tanabe, Toyokazu
2016-01-21
Three different porous Au catalysts that exhibit high catalytic activity for CO oxidation were prepared by the leaching of Al from an intermetallic compound, Al{sub 2}Au, with 10 wt. %-NaOH, HNO{sub 3}, or HCl aqueous solutions. The catalysts were investigated using Brunauer-Emmett-Teller measurements, synchrotron X-ray powder diffraction, hard X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy (TEM). Broad diffraction peaks generated during the leaching process correlated with high activity for all the porous Au catalysts. CO oxidation catalyzed by porous Au leached with NaOH and HNO{sub 3} is considered to be dominated by different mechanisms atmore » low (< 320 K) and high (> 370 K) temperatures. Activity in the low-temperature region is mainly attributed to the perimeter interface between residual Al species (AlO{sub x}) and porous Au, whereas activity in the high-temperature region results from a high density of lattice defects such as twins and dislocations, which were evident from diffraction peak broadening and were observed with high-resolution TEM in the porous Au leached with NaOH. It is proposed that atoms located at lattice defects on the surfaces of porous Au are the active sites for catalytic reactions.« less
USDA-ARS?s Scientific Manuscript database
Maltose, the primary product of starch degradation during mashing, has the potential as a compatible solute to affect the activity of and increase the thermostability of barley malt alpha-amylase activity at high temperatures used in mashing and temperatures above those normally used in mashing. To ...
It's Our School Too: Youth Activism as Educational Reform, 1951-1979
ERIC Educational Resources Information Center
Ajunwa, Kelechi
2011-01-01
Activism has the potential for reform (Howard, 1976). Unlike previous studies on high school activism this study places a primary focus on underground newspapers and argues that underground newspapers allowed high school students to function as activists as well as educational reformers. In order to make this argument, this study examined over 150…
Activities Selected from the High School Geography Project.
ERIC Educational Resources Information Center
Natoli, Salvatore J., Ed.; And Others
Out of approximately 50 activities which were, for a variety of reasons, not included in the final version of the High School Geography Project course, Geography in an Urban Age, the HSGP staff selected eight which would be useful in many secondary school classrooms. The activities included here are: 1) Operation Bigger Beef (on themes of cultural…
Influence of Activity Mode on Feeling States of High School Physical Education Students
ERIC Educational Resources Information Center
Hannon, James C.; Pellet, Tracey L.
2005-01-01
The purpose of this study was to determine if changes in positive well-being, psychological distress, fatigue, and enjoyment vary as a function of physical activity mode. Fifty-five senior high school students participated in one of four fitness activities including two defined as traditional (running and step-aerobics) and two defined as…
ERIC Educational Resources Information Center
Christensen, Rhonda; Knezek, Gerald; Tyler-Wood, Tandra
2015-01-01
This study examines positive dispositions reported by middle school and high school students participating in programs that feature STEM-related activities. Middle school students participating in school-to-home hands-on energy monitoring activities are compared to middle school and high school students in a different project taking part in…
Relationships between solar activity and climate change. [sunspot cycle effects on lower atmosphere
NASA Technical Reports Server (NTRS)
Roberts, W. O.
1974-01-01
Recurrent droughts are related to the double sunspot cycle. It is suggested that high solar activity generally increases meridional circulations and blocking patterns at high and intermediate latitudes, especially in winter. This effect is related to the sudden formation of cirrus clouds during strong geomagnetic activity that originates in the solar corpuscular emission.
Participation in Daily Activities of Young Adults with High Functioning Autism Spectrum Disorder
ERIC Educational Resources Information Center
McCollum, Mary; LaVesser, Patti; Berg, Christine
2016-01-01
Young adults with an autism spectrum disorder (ASD) struggle to assume adult roles. This research assessed the feasibility of using the Adolescent and Young Adult Activity Card Sort (AYA-ACS) with emerging adults with high functioning ASD. Two phases were utilized during this research: (1) comparing the activity participation reported by emerging…
ERIC Educational Resources Information Center
Fransen, Shelly Lynette
2013-01-01
High quality student engagement activities are essential if students are to be successful learners. Over the years, many instructional strategies and models have been devised to encourage teachers to develop student engagement activities that result in high achievement. The Reading First Model initiative was introduced as a part of the No Child…
Enzymes in Commercial Cellulase Preparations Bind Differently to Dioxane Extracted Lignins
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yarbrough, John M.; Mittal, Ashutosh; Katahira, Rui
Commercial fungal cellulases used in biomass-to-biofuels processes can be grouped into three general classes: native, augmented, and engineered. To evaluate lignin binding affinities of different enzyme activities in various commercial cellulase formulations in order to determine if enzyme losses due to lignin binding can be modulated by using different enzymes of the same activity We used water:dioxane (1:9) to extract lignin from pretreated corn stover. Commercial cellulases were incubated with lignin and the unbound supernatants were evaluated for individual enzyme loss by SDS=PAGE and these were correlated with activity loss using various pNP-sugar substrates. Colorimetric assays for general glycosyl hydrolasemore » activities showed distinct differences in enzyme binding to lignin for each enzyme activity. Native systems demonstrated low binding of endo- and exo-cellulases, high binding of xylanase, and moderate ..beta..-glucosidase binding. Engineered cellulase mixtures exhibited low binding of exo-cellulases, very strong binding of endocellulases and ..beta..- glucosidase, and mixed binding of xylanase activity. The augmented cellulase had low binding of exocellulase, high binding of endocellulase and xylanase, and moderate binding of ..beta..-glucosidase activities. Bound and unbound activities were correlated with general molecular weight ranges of proteins as measured by loss of proteins bands in bound fractions on SDS-PAGE gels. Lignin-bound high molecular weight bands correlated with binding of ..beta..-glucosidase activity. While ..beta..-glucosidases demonstrated high binding in many cases, they have been shown to remain active. Bound low molecular weight bands correlated with xylanase activity binding. Contrary to other literature, exocellulase activity did not show strong lignin binding. The variation in enzyme activity binding between the three classes of cellulases preparations indicate that it is certainly possible to alter the binding of specific glycosyl hydrolase activities. It remains unclear whether loss of endocellulase activity to lignin binding is problematic for biomass conversion.« less
NASA's Hall Thruster Program 2002
NASA Technical Reports Server (NTRS)
Jankovsky, Robert S.; Jacobson, David T.; Pinero, Luis R.; Manzella, David H.; Hofer, Richard R.; Peterson, Peter Y.
2002-01-01
The NASA Hall thruster program currently supports a number of tasks related to high power thruster development for a number of customers including the Energetics Program (formerly called the Space-based Program), the Space Solar Power Program, and the In-space Propulsion Program. In program year 2002, two tasks were central to the NASA Hall thruster program: 1) the development of a laboratory Hall thruster capable of providing high thrust at high power-, and 2) investigations into operation of Hall thrusters at high specific impulse. In addition to these two primary thruster development activities, there are a number of other on-going activities supported by the NASA Hall thruster program. These additional activities are related to issues such as high-power power processor architecture, thruster lifetime, and spacecraft integration.
Flow Control Research at NASA Langley in Support of High-Lift Augmentation
NASA Technical Reports Server (NTRS)
Sellers, William L., III; Jones, Gregory S.; Moore, Mark D.
2002-01-01
The paper describes the efforts at NASA Langley to apply active and passive flow control techniques for improved high-lift systems, and advanced vehicle concepts utilizing powered high-lift techniques. The development of simplified high-lift systems utilizing active flow control is shown to provide significant weight and drag reduction benefits based on system studies. Active flow control that focuses on separation, and the development of advanced circulation control wings (CCW) utilizing unsteady excitation techniques will be discussed. The advanced CCW airfoils can provide multifunctional controls throughout the flight envelope. Computational and experimental data are shown to illustrate the benefits and issues with implementation of the technology.
Serum diamine oxidase activity as a diagnostic test for histamine intolerance.
Mušič, Ema; Korošec, Peter; Šilar, Mira; Adamič, Katja; Košnik, Mitja; Rijavec, Matija
2013-05-01
Histamine intolerance (HIT) is characterized by an imbalance between histamine intake and the capacity for histamine degradation. The main enzyme for metabolizing ingested histamine is diamine oxidase (DAO). Determining DAO activity in serum may be useful in diagnosing HIT. Over a period of 3.5 years we recruited 316 subjects with clinically suspected HIT and 55 healthy controls. Serum DAO activity was measured with a quantitative enzyme immunoassay. Twenty patients with highly reduced DAO activity went on a histamine-free diet for 6-12 months. Afterwards, their DAO activity was determined again. We found that DAO activity was significantly lower in patients than in healthy control subjects (P < 0.0001). Furthermore, 54 patients had highly reduced serum DAO activity (< 40 HDU/ml). Their main symptoms involved the skin, gastrointestinal tract, respiratory system, and eyes. In all the 20 patients with highly reduced DAO activity, the main clinical symptoms typical of histamine intolerance disappeared after they adopted a histamine-free diet. Furthermore, the serum DAO activity values measured increased significantly (P < 0.0001). Our results suggest that determining DAO activity in serum is a useful tool in diagnosing HIT. Furthermore, our results showed the benefit of a histamine-free diet because after the diet the majority of symptoms disappeared and the serum DAO activity significantly increased.
Comparing high and low acculturated mothers and physical activity in Hispanic children.
Olvera, Norma; Smith, Dennis W; Lee, Chanam; Liu, Jian; Lee, Jay; Kim, Jun-Hyun; Kellam, Stephanie F
2011-09-01
Parents represent a key ecological component in influencing their child's physical activity. The aim of this exploratory study was to assess the relationship between maternal acculturation and physical activity in Hispanic children. 102 Hispanic mothers (mean age 36.2 yrs; +SD 7.3 yrs) and their children (mean age 10.0 yrs, +SD 0.8 yrs) participated. Most of the mothers (74%) were foreign-born, with 62% classified as low acculturated and 38% high acculturated. Demographic, acculturation, and anthropometric measures were completed by mothers and children. Physical activity was measured using accelerometers. Relationships between maternal acculturation and demographic variables and children's physical activity were examined using chi-square, Analysis of Variance, and simple regression. Children had higher physical activity levels than their mothers (t(49) = -7.87, P < .0001). Significant correlations between maternal and child's physical activity levels were observed in moderate (r2 = 0.13, P = .001), vigorous (r2 = 0.08, P = .05), and moderate-to-vigorous physical activity (r2 = 0.17, P = .002). Low acculturated mothers were more likely to have active children compared with high acculturated mothers. Maternal BMI and other demographic characteristics were not significantly associated with child's physical activity. Findings from this study revealed an association among maternal acculturation, role modeling, and child's physical activity.
Compound Structure-Independent Activity Prediction in High-Dimensional Target Space.
Balfer, Jenny; Hu, Ye; Bajorath, Jürgen
2014-08-01
Profiling of compound libraries against arrays of targets has become an important approach in pharmaceutical research. The prediction of multi-target compound activities also represents an attractive task for machine learning with potential for drug discovery applications. Herein, we have explored activity prediction in high-dimensional target space. Different types of models were derived to predict multi-target activities. The models included naïve Bayesian (NB) and support vector machine (SVM) classifiers based upon compound structure information and NB models derived on the basis of activity profiles, without considering compound structure. Because the latter approach can be applied to incomplete training data and principally depends on the feature independence assumption, SVM modeling was not applicable in this case. Furthermore, iterative hybrid NB models making use of both activity profiles and compound structure information were built. In high-dimensional target space, NB models utilizing activity profile data were found to yield more accurate activity predictions than structure-based NB and SVM models or hybrid models. An in-depth analysis of activity profile-based models revealed the presence of correlation effects across different targets and rationalized prediction accuracy. Taken together, the results indicate that activity profile information can be effectively used to predict the activity of test compounds against novel targets. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Van Holle, Veerle; Van Cauwenberg, Jelle; Gheysen, Freja; Van Dyck, Delfien; Deforche, Benedicte; Van de Weghe, Nico; De Bourdeaudhuij, Ilse
2016-01-01
Better physical functioning in the elderly may be associated with higher physical activity levels. Since older adults spend a substantial part of the day in their residential neighborhood, the neighborhood physical environment may moderate associations between functioning and older adults' physical activity. The present study investigated the moderating role of the objective and perceived physical environment on associations between Belgian older adults' physical functioning and transport walking, recreational walking, and moderate-to-vigorous physical activity. Data from 438 older adults were included. Objective physical functioning was assessed using the Short Physical Performance Battery. Potential moderators included objective neighborhood walkability and perceptions of land use mix diversity, access to recreational facilities, access to services, street connectivity, physical barriers for walking, aesthetics, crime-related safety, traffic speeding-related safety, and walking infrastructure. Transport and recreational walking were self-reported, moderate-to-vigorous physical activity was assessed through accelerometers. Multi-level regression analyses were conducted using MLwiN to examine two-way interactions between functioning and the environment on both walking outcomes. Based on a previous study where environment x neighborhood income associations were found for Belgian older adults' moderate-to-vigorous physical activity, three-way functioning x environment x income interactions were examined for moderate-to-vigorous physical activity. Objectively-measured walkability moderated the association between functioning and transport walking; this positive association was only present in high-walkable neighborhoods. Moreover, a three-way interaction was observed for moderate-to-vigorous physical activity. Only in high-income, high-walkable neighborhoods, there was a positive association between functioning and moderate-to-vigorous physical activity. No functioning x walkability interactions were observed for recreational walking, and none of the perceived environmental variables moderated the positive association between physical functioning and the physical activity outcomes. For older adults with better physical functioning, living in a high-walkable neighborhood could be beneficial to engage in more transport walking. Living in high-income, high-walkable neighborhoods and having better functioning might also be beneficial for more engagement in moderate-to-vigorous physical activity. This might suggest a protective role of neighborhood walkability for preventing declining physical functioning and consequently decreasing physical activity levels in older adults. However, given the cross-sectional design of the present study, this suggestion needs to be confirmed through longitudinal assessment investigating over-time changes in the observed associations.
Enabling High Energy Density Li-Ion Batteries through Li{sub 2}O Activation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abouimrane, Ali; Cui, Yanjie; Chen, Zonghai
2016-09-01
Lithium oxide (Li2O) is activated in the presence of a layered composite cathode material (HEM) significantly increasing the energy density of lithium-ion batteries. The degree of activation depends on the current rate, electrolyte salt, and anode type. In full-cell tests, the Li2O was used as a lithium source to counter the first-cycle irreversibility of high-capacity composite alloy anodes. When Li2O is mixed with HEM to serve as a cathode, the electrochemical performance was improved in a full cell having an SiO-SnCoC composite as an anode. The mechanism behind the Li2O activation could also explain the first charge plateau and themore » abnormal high capacity associated with these high energy cathode materials.« less
NASA Technical Reports Server (NTRS)
Spencer, Michael; Dunbar, Scott; Chen, Curtis
2013-01-01
The Soil Moisture Active/Passive (SMAP) mission is scheduled for a late 2014 launch date. The mission will use both active radar and passive radiometer instruments at L-Band. In order to achieve a wide swath at sufficiently high resolution for both active and passive channels, an instrument architecture that uses a large rotating reflector is employed. In this paper, a focus will be places on the radar design and associated data products at high latitudes. The radar will employ synthetic-aperture processing to achieve a "moderate" resolution dual-pol product over a 1000 km swath. Because the radar is operating continuously, very frequent temporal coverage will be achieved at high latitudes. This data will be used, among other things, to produce a surface freeze/thaw state data product.
Activation of the E1 Ultra High Pressure Propulsion Test Facility at Stennis Space Center
NASA Technical Reports Server (NTRS)
Messer, Bradley; Messer, Elisabeth; Sewell, Dale; Sass, Jared; Lott, Jeff; Dutreix, Lionel, III
2001-01-01
After a decade of construction and a year of activation the El Ultra High Pressure Propulsion Test Facility at NASA's Stennis Space Center is fully operational. The El UHP Propulsion Test Facility is a multi-cell, multi-purpose component and engine test facility . The facility is capable of delivering cryogenic propellants at low, high, and ultra high pressures with flow rates ranging from a few pounds per second up to two thousand pounds per second. Facility activation is defined as a series of tasks required to transition between completion of construction and facility operational readiness. Activating the El UHP Propulsion Test Facility involved independent system checkouts, propellant system leak checks, fluid and gas sampling, gaseous system blow downs, pressurization and vent system checkouts, valve stability testing, valve tuning cryogenic cold flows, and functional readiness tests.
A neuroimaging study of conflict during word recognition.
Riba, Jordi; Heldmann, Marcus; Carreiras, Manuel; Münte, Thomas F
2010-08-04
Using functional magnetic resonance imaging the neural activity associated with error commission and conflict monitoring in a lexical decision task was assessed. In a cohort of 20 native speakers of Spanish conflict was introduced by presenting words with high and low lexical frequency and pseudo-words with high and low syllabic frequency for the first syllable. Erroneous versus correct responses showed activation in the frontomedial and left inferior frontal cortex. A similar pattern was found for correctly classified words of low versus high lexical frequency and for correctly classified pseudo-words of high versus low syllabic frequency. Conflict-related activations for language materials largely overlapped with error-induced activations. The effect of syllabic frequency underscores the role of sublexical processing in visual word recognition and supports the view that the initial syllable mediates between the letter and word level.
NASA Astrophysics Data System (ADS)
Xiao, Jian-Hua; Huang, Wei-Qing; Hu, Yong-sheng; Zeng, Fan; Huang, Qin-Yi; Zhou, Bing-Xin; Pan, Anlian; Li, Kai; Huang, Gui-Fang
2018-02-01
High photocatalytic activity and photostability are the pursuit of the goal for designing promising photocatalysts. Herein, using ZnO to encapsulate ZnS nanoparticles is proposed as an effective strategy to enhance photocatalytic activity and anti-photocorrosion. The ZnS/ZnO core/shell heterostructures are obtained via an annealing treatment of ZnS nanoparticles produced by a facile wet chemical approach. Due to its small size, the nascent cubic sphalerite ZnS (s-ZnS) converts into a hexagonal wurtzite ZnS (w-ZnS)/ZnO core/shell structure after annealing treatment. In situ oxidation leads to increasing ZnO, simultaneously decreasing the w-ZnS content in the resultant w-ZnS/ZnO with thermal annealing time. The w-ZnS/ZnO core/shell heterostructures show high photocatalytic activity, demonstrated by the photodegradation rate of methylene blue being up to ten-fold and seven-fold higher than that of s-ZnS under UV and visible light irradiation, respectively, and the high capability of degrading rhodamine B. The enhanced photocatalytic activity may be attributed to the large specific surface and improved charge carrier separation at the core/shell interface. Moreover, it displays high photostability owing to the protection of the ZnO shell, greatly inhibiting the photocorrosion of ZnS. This facile in situ oxidation is effective and easily scalable, providing opportunities for developing novel core/shell structure photocatalysts with high activity and photostability.
Matsushita, Makoto; Harajiri, Sanae; Tabata, Shiori; Yukimasa, Nobuyasu; Muramoto, Yoshimi; Komoda, Tsugikazu
2013-04-01
We previously reported that two intestinal alkaline phosphatase (IAP) isoforms, high molecular mass IAP (HIAP) and normal molecular mass IAP (NIAP), appear in healthy serum with our Triton-PAGE method for determination of ALP isozymes. In addition, HIAP is chiefly present in blood group B or O secretors, and a large amount of NIAP is secreted into the circulation after high-fat meal in blood group B or O secretors. In the present paper, we investigated the relationship between alkaline phosphatase (ALP) activity in early morning with the patient in a fasted state and the dinner intake of previous night. Two types of dinner were prepared; a low-fat meal (520 kcal), and a high-fat meal (1,040 kcal). Subjects ate the 2 types of dinner on different days. The mean ALP activities at 14 h after high-fat meal ingestion in blood group B or O secretors (n=14) from JSCC and IFCC methods were 8.8% and 5.2% higher than those at 14 h after low-fat meal ingestion in blood group B or O secretors, respectively. The increases in ALP activity between after high-fat meal and low-fat meal were nearly identical to the increases in NIAP activity. These results suggest that a high-fat meal is more likely to affect ALP activity at the early morning with the patient in a fasted state in blood group B or O secretors.
High Sulfation and a High Molecular Weight Are Important for Anti-hepcidin Activity of Heparin
Asperti, Michela; Naggi, Annamaria; Esposito, Emiliano; Ruzzenenti, Paola; Di Somma, Margherita; Gryzik, Magdalena; Arosio, Paolo; Poli, Maura
2016-01-01
Heparins are efficient inhibitors of hepcidin expression even in vivo, where they induce an increase of systemic iron availability. Heparins seem to act by interfering with BMP6 signaling pathways that control the expression of liver hepcidin, causing the suppression of SMAD1/5/8 phosphorylation. The anti-hepcidin activity persists also when the heparin anticoagulant property is abolished or reduced by chemical reactions of oxidation/reduction (glycol-split, Gs-Heparins) or by high sulfation (SS-Heparins), but the structural characteristics needed to optimize this inhibitory activity have not been studied in detail. To this aim we analyzed three different heparins (Mucosal Heparin, the Glycol split RO-82, the partially desulfated glycol-split RO-68 and the oversulfated SSLMWH) and separated them in fractions of molecular weight in the range 4–16 kD. Since the distribution of the negative charges in heparins contributes to the activity, we produced 2-O- and 6-O-desulfated heparins. These derivatives were analyzed for the capacity to inhibit hepcidin expression in hepatic HepG2 cells and in mice. The two approaches produced consistent results and showed that the anti-hepcidin activity strongly decreases with molecular weight below 7 kD, with high N-acetylation and after 2-O and 6-O desulfation. The high sulfation and high molecular weight properties for efficient anti-hepcidin activity suggest that heparin is involved in multiple binding sites. PMID:26955355
Lim, Soohwan; Park, Jeongmoo; Lee, Nayoung; Jeong, Jinkil; Toh, Shigeo; Watanabe, Asuka; Kim, Junghyun; Kang, Hyojin; Kim, Dong Hwan; Kawakami, Naoto; Choi, Giltsu
2013-12-01
Seeds monitor the environment to germinate at the proper time, but different species respond differently to environmental conditions, particularly light and temperature. In Arabidopsis thaliana, light promotes germination but high temperature suppresses germination. We previously reported that light promotes germination by repressing SOMNUS (SOM). Here, we examined whether high temperature also regulates germination through SOM and found that high temperature activates SOM expression. Consistent with this, som mutants germinated more frequently than the wild type at high temperature. The induction of SOM mRNA at high temperature required abscisic acid (ABA) and gibberellic acid biosynthesis, and ABA-insensitive3 (ABI3), ABI5, and DELLAs positively regulated SOM expression. Chromatin immunoprecipitation assays indicated that ABI3, ABI5, and DELLAs all target the SOM promoter. At the protein level, ABI3, ABI5, and DELLAs all interact with each other, suggesting that they form a complex on the SOM promoter to activate SOM expression at high temperature. We found that high-temperature-inducible genes frequently have RY motifs and ABA-responsive elements in their promoters, some of which are targeted by ABI3, ABI5, and DELLAs in vivo. Taken together, our data indicate that ABI3, ABI5, and DELLAs mediate high-temperature signaling to activate the expression of SOM and other high-temperature-inducible genes, thereby inhibiting seed germination.
Effects of Shiitake Intake on Serum Lipids in Rats Fed Different High-Oil or High-Fat Diets.
Asada, Norihiko; Kairiku, Rumi; Tobo, Mika; Ono, Akifumi
2018-04-27
Shiitake (Lentinula edodes) extract, eritadenine, has been shown to reduce cholesterol levels, and its hypocholesterolemic actions are involved in the metabolism of methionine. However, the mechanisms by which eritadenine affects cholesterol metabolism in animals fed a high-fat diet containing different sources of lipids have not yet been elucidated in detail. This study was conducted to investigate the effects of shiitake supplementation on serum lipid concentrations in rats fed a diet including a high amount of a plant oil (HO [high oil] and HOS [high oil with shiitake] groups), animal fat (HF [high fat] and HFS [high fat with shiitake] groups), or MCT- (medium-chain triglyceride-) rich plant oil (HM [high MCT] and HMS [high MCT with shiitake] groups). Rats in the HOS, HFS, and HMS groups were fed shiitake. When rats were fed a diet containing shiitake, serum triglyceride, cholesterol levels, and LCAT (lecithin-cholesterol acyltransferase) activities were lower in rats given MCT-rich plant oil than in those that consumed lard. The lipid type in the diet with shiitake also affected serum cholesterol levels and LCAT activities. The diet containing MCT-rich plant oil showed the greatest rates of decrease in all serum lipid profiles and LCAT activities. These results suggest that shiitake and MCT-rich plant oil work together to reduce lipid profiles and LCAT activity in serum.
Clark, Uraina S; Sweet, Lawrence H; Morgello, Susan; Philip, Noah S; Cohen, Ronald A
2017-06-01
Relative to HIV-negative adults, HIV+ adults report elevated levels of early life stress (ELS). In non-HIV samples, high ELS has been linked to abnormalities in brain structure and function, as well as increased risk of neuropsychiatric symptoms. Yet, little is known about the neural effects of high ELS, and their relation to elevated neuropsychiatric symptoms, in HIV+ adults. Recent studies have revealed combined effects of HIV and high ELS on amygdala morphometry. Aberrant amygdala activity is prominently implicated in studies of neuropsychiatric symptomology in non-HIV samples. Hence, this preliminary study examined: 1) the combined effects of HIV and high ELS on amygdala activity, and 2) the relation between amygdala activity and neuropsychiatric symptoms in HIV+ adults. We included 28 HIV+ adults and 25 demographically-matched HIV-negative control (HC) adults. ELS exposure was quantified using a retrospective ELS questionnaire, which defined four groups: HIV+ Low-ELS (N = 15); HIV+ High-ELS (N = 13); HC Low-ELS (N = 16); and HC High-ELS (N = 9). Participants completed a battery of neuropsychiatric measures. BOLD fMRI assessed amygdala reactivity during explicit observation of fearful/angry faces. High-ELS participants demonstrated reduced levels of amygdala reactivity relative to Low-ELS participants. HIV+ High-ELS participants reported higher levels of neuropsychiatric symptoms than all other groups. In the HIV+ group, lower amygdala responses were associated with higher neuropsychiatric symptoms, particularly depression, anxiety, and alexithymia. Collectively, these results suggest that high ELS exposure is a significant risk factor for neuropsychiatric symptoms in HIV+ adults. Furthermore, our results implicate ELS-related abnormalities in amygdala activity in the etiology of neuropsychiatric symptoms in HIV+ adults.
High glucose impaired estrogen receptor alpha signaling via β-catenin in osteoblastic MC3T3-E1.
Wang, Rui; Gao, Dong; Zhou, Yin; Chen, Lu; Luo, Bin; Yu, Yanrong; Li, Hao; Hu, Jiawei; Huang, Qiren; He, Ming; Peng, Weijie; Luo, Dan
2017-11-01
Diabetic Mellitus is a risk factor for osteoporosis. It has been suggested that altered estrogen or estrogen receptor α/β (ERα/β) signaling may be involved in diabetic osteoporosis. The present study is to investigate the effects of high glucose on ERα/β signaling in osteoblastic MC3T3-E1 and how the altered signaling of ERα/β affect osteoblastic bone formation. ERα/β signaling was demonstrated as ERα/β protein expression (Western Blotting) and ER transcription activity (Luciferase Reporter assays). Proliferation (WSK-1 assaying), differentiation (ALP staining) and mineralization (Alizalard Red staining) of MC3T3-E1 were examined to evaluate bone formation function. It has been found that high glucose increased ERα/β expression dose-dependently and time-dependently, but high glucose (33mM) decreased ERα transcription activity. 17β-estradiol increased the ERα/β expression dose-dependently in normal medium, but decreased the ERα/β expression dose-dependently in medium with high glucose (33mM). High glucose decreased bone formation and also decreased the osteogenic effects of 17β-estradiol (10 -8 M). High glucose decreased β-catenin expression dose-dependently and time-dependently. LiCl, an inhibitor of β-catenin degradation, decreased ERα expression but increased ERα transcription activity. When compared with high glucose treatment, LiCl (5mM) increased ALP activity and calcified nodes. Besides, high glucose also decreased the protein expression PI-3K, pAKT/AKT, GSK-3β. In conclusion, the present study suggested that high glucose may impair ERα transcription activity by inhibiting β-catenin signaling in osteoblastic MC3T3-E1, leading decreased bone formation ligand-dependently or ligand-independently. Copyright © 2017 Elsevier Ltd. All rights reserved.
Physical Activity Levels in Portuguese High School Physical Education
ERIC Educational Resources Information Center
Marmeleira, Jose Francisco Filipe; Aldeias, Nuno Micael Carrasqueira; da Graca, Pedro Miguel dos Santos Medeira
2012-01-01
The main aim of this study was to evaluate the physical activity (PA) levels of high school Portuguese students during physical education (PE) and investigate the association of PA levels with students' goal orientation and intrinsic motivation. Forty-six students from three high schools participated. Heart rate telemetry and pedometry were used…
Biocatalytic material comprising multilayer enzyme coated fiber
Kim, Jungbae [Richland, WA; Kwak, Ja Hun [Richland, WA; Grate, Jay W [West Richland, WA
2009-11-03
The present invention relates generally to high stability, high activity biocatalytic materials and processes for using the same. The materials comprise enzyme aggregate coatings having high biocatalytic activity and stability useful in heterogeneous environment. These new materials provide a new biocatalytic immobilized enzyme system with applications in bioconversion, bioremediation, biosensors, and biofuel cells.
ERIC Educational Resources Information Center
Bohnert, Amy M.; Aikins, Julie Wargo; Arola, Nicole T.
2013-01-01
Although organized activities (OAs) have been established as important contexts of development, limited work has examined the role of OAs across the high school transition in buffering adolescents' social adjustment by providing opportunities for visibility and peer affiliation. The transition to high school is characterized by numerous changes…
Introduction to Vocations. High Tech Focus. Final Report 1984-85.
ERIC Educational Resources Information Center
Wayne Township Schools, NJ.
This report contains the materials that were developed during a project to make middle-grade students more aware of high tech careers through the following activities: (1) teacher and student visitations of community sites to explore high tech careers in 15 occupational clusters; (2) exploratory activities to facilitate linkages and articulation…
Jhong, Huei-Ru Molly; Tornow, Claire E; Kim, Chaerin; Verma, Sumit; Oberst, Justin L; Anderson, Paul S; Gewirth, Andrew A; Fujigaya, Tsuyohiko; Nakashima, Naotoshi; Kenis, Paul J A
2017-11-17
Multiple approaches will be needed to reduce the atmospheric CO 2 levels, which have been linked to the undesirable effects of global climate change. The electroreduction of CO 2 driven by renewable energy is one approach to reduce CO 2 emissions while producing chemical building blocks, but current electrocatalysts exhibit low activity and selectivity. Here, we report the structural and electrochemical characterization of a promising catalyst for the electroreduction of CO 2 to CO: Au nanoparticles supported on polymer-wrapped multiwall carbon nanotubes. This catalyst exhibits high selectivity for CO over H 2 : 80-92 % CO, as well as high activity: partial current density for CO as high as 160 mA cm -2 . The observed high activity, originating from a high electrochemically active surface area (23 m 2 g -1 Au), in combination with the low loading (0.17 mg cm -2 ) of the highly dispersed Au nanoparticles underscores the promise of this catalyst for efficient electroreduction of CO 2 . © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Feng, Liang-Liang; Yu, Guangtao; Wu, Yuanyuan; Li, Guo-Dong; Li, Hui; Sun, Yuanhui; Asefa, Tewodros; Chen, Wei; Zou, Xiaoxin
2015-11-11
Elaborate design of highly active and stable catalysts from Earth-abundant elements has great potential to produce materials that can replace the noble-metal-based catalysts commonly used in a range of useful (electro)chemical processes. Here we report, for the first time, a synthetic method that leads to in situ growth of {2̅10} high-index faceted Ni3S2 nanosheet arrays on nickel foam (NF). We show that the resulting material, denoted Ni3S2/NF, can serve as a highly active, binder-free, bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Ni3S2/NF is found to give ∼100% Faradaic yield toward both HER and OER and to show remarkable catalytic stability (for >200 h). Experimental results and theoretical calculations indicate that Ni3S2/NF's excellent catalytic activity is mainly due to the synergistic catalytic effects produced in it by its nanosheet arrays and exposed {2̅10} high-index facets.
Chen, Jyu-Lin; Weiss, Sandra; Heyman, Melvin B; Lustig, Robert
2011-04-01
The objective of this study is to explore risk factors associated with overweight and high blood pressure in Chinese American children. Students and their parents were recruited from Chinese language schools in the San Francisco Bay Area. Data were collected on 67 children and their mothers, and included children's weight, height, waist and hip circumferences, blood pressure, level of physical activity, dietary intake, usual food choice, knowledge about nutrition and physical activity, and self-efficacy regarding diet and physical activity. Mothers completed questionnaires on demographic data and acculturation. About 46% of children had a body mass index exceeding the 85th percentile. Lower level of maternal acculturation is a risk factor for overweight and higher waist to hip ratio. Children's unhealthy food choices were predictive of high body mass index and high systolic blood pressure, whereas older age and less physical activity in children were predictors of high diastolic blood pressure. Developing culturally sensitive and developmentally appropriate interventions to reduce overweight and high blood pressure is critical to reduce health disparities among minority children.
Keane, N M; Price, P; Lee, S; Stone, S F; French, M A
2001-01-01
This study evaluates serum CD26 (dipeptidyl peptidase IV, DPPIV) enzyme activity and serum levels of soluble CD30 as markers of T1 and T2 cytokine environments in HIV patients who achieved immune reconstitution after highly active antiretroviral therapy (HAART). Patients who had experienced inflammatory disease associated with pre-existent opportunistic infections after HAART (immune restoration diseases, IRD) were considered separately. Serum sCD30 levels and CD26 (DPPIV) enzyme activity were compared with IFN-γ production by PBMC cultured with cytomegalovirus (CMV) antigen in controls and patient groups. High sCD30 levels were associated with low IFN-γ production after antigenic stimulation in control subjects and, to a lesser extent, in immune reconstituted HIV patients. There was no association between serum CD26 (DPPIV) enzyme activity and IFN-γ production or sCD30 levels. Serum sCD30 levels and CD26 (DPPIV) enzyme activity were significantly increased in immune reconstituted patients with high HIV viral loads. Patients who had experienced CMV retinitis as an IRD had significantly higher sCD30 levels than all other patient groups. Hence, high sCD30 levels may be a marker of a T2 cytokine environment in HIV patients with immune reconstitution and are associated with higher HIV viral loads and a history of CMV associated IRD. PMID:11678906