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Sample records for activity concentrations obtained

  1. Antioxidant activities of protein hydrolysates obtained from the housefly larvae.

    PubMed

    Zhang, Huan; Wang, Pan; Zhang, Ai-Jun; Li, Xuan; Zhang, Ji-Hong; Qin, Qi-Lian; Wu, Yi-Jun

    2016-09-01

    The housefly is an important resource insect and the housefly larvae are ideal source of food additives. The housefly larvae protein hydrolysates were obtained by enzymatic hydrolysis by alcalase and neutral proteinase. Their antioxidant activities were investigated, including the superoxide and hydroxyl radicalscavenging activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, reducing power and metal chelating activity. The antioxidant activities of both hydrolysates increased with their increasing concentrations. The alcalase hydrolysate (AH) showed higher scavenging activities against hydroxyl radical and superoxide anion radical at low concentrations and higher metal-chelating activity than the neutral proteinase hydrolysate (NPH). The NPH exhibited higher scavenging activity against DPPH free radical and higher reducing power than the AH. Both hydrolysates showed more than 50% superoxide anion radical-scavenging activity at 10 μg/mL. These results indicate that both housefly larvae protein hydrolysates display high antioxidant activities and they could serve as potential natural antioxidant food additives. PMID:27630047

  2. Methods for obtaining active mutanase preparations from Paenibacillus curdlanolyticus.

    PubMed

    Pleszczyńska, Małgorzata; Wiater, Adrian; Szczodrak, Janusz

    2008-01-01

    The strain Paenibacillus curdlanolyticus MP-1 was used to obtain mutan-hydrolyzing enzymes. Different methods of precipitation and concentration of the post culture liquid were tested. All these methods produced satisfactory results in regard to the overall activity of mutanase and yielded active preparations of the enzyme. The best precipitation was obtained with propanol -98% of the initial enzyme activity was preserved with a purification of 2-fold. Salting out with ammonium sulfate at 50% saturation gave mutanase recovery of 77% and a purification of around 2-fold. Ultrafiltration yielded an about 10-fold concentrated preparation of the enzyme with a yield of 98%. Lyophilization and concentration of the culture broth (in the range from 5 to 20 times) in a vacuum evaporator yielded active crude preparations with mutanase recovery of 97%.

  3. Methods to obtain protein concentrates from jumbo squid (Dosidicus gigas) and evaluation of their functionality.

    PubMed

    Galvez-Rongel, A; Ezquerra-Brauer, J M; Ocano-Higuera, V M; Ramirez-Wong, B; Torres-Arreola, W; Rouzaud-Sandez, O; Marquez-Rios, E

    2014-03-01

    Jumbo squid is an important fishery resource in Mexico, and its muscle is lean and white and it has a very low price in the market. It is abundant, but with little or nothing added value, therefore is necessary to search alternatives of processing. Due to muscle characteristics, the aim of this study was to obtain protein concentrates using different methods. They were obtained by means of acidic (acid protein concentrates) and alkaline (alkaline protein concentrates) dissolution. Moreover, a protein concentrate was obtained by direct isoelectric precipitation and by the traditional method (neutral protein concentrates). The yield with better results was alkaline protein concentrates (63.58 ± 1.8%). The gel hardness was significantly different (p < 0.05), especially for the alkaline protein concentrates. The acid protein concentrates, isoelectric precipitation and alkaline protein concentrates were better with regard to the neutral protein concentrates, concerning the emulsifying and foaming properties. The protein concentrates by means of alkaline dissolution gave a better gelling property, but all the processes had the potential to obtain protein with emulsifying and foaming properties.

  4. Locating and quantifying gas emission sources using remotely obtained concentration data

    NASA Astrophysics Data System (ADS)

    Hirst, Bill; Jonathan, Philip; González del Cueto, Fernando; Randell, David; Kosut, Oliver

    2013-08-01

    We describe a method for detecting, locating and quantifying sources of gas emissions to the atmosphere using remotely obtained gas concentration data; the method is applicable to gases of environmental concern. We demonstrate its performance using methane data collected from aircraft. Atmospheric point concentration measurements are modelled as the sum of a spatially and temporally smooth atmospheric background concentration, augmented by concentrations due to local sources. We model source emission rates with a Gaussian mixture model and use a Markov random field to represent the atmospheric background concentration component of the measurements. A Gaussian plume atmospheric eddy dispersion model represents gas dispersion between sources and measurement locations. Initial point estimates of background concentrations and source emission rates are obtained using mixed ℓ2 - ℓ1 optimisation over a discretised grid of potential source locations. Subsequent reversible jump Markov chain Monte Carlo inference provides estimated values and uncertainties for the number, emission rates and locations of sources unconstrained by a grid. Source area, atmospheric background concentrations and other model parameters, including plume model spreading and Lagrangian turbulence time scale, are also estimated. We investigate the performance of the approach first using a synthetic problem, then apply the method to real airborne data from a 1600 km2 area containing two landfills, then a 225 km2 area containing a gas flare stack.

  5. Antioxidative activities of fractions obtained from brewed coffee.

    PubMed

    Yanagimoto, Kenichi; Ochi, Hirotomo; Lee, Kwang-Geun; Shibamoto, Takayuki

    2004-02-11

    The antioxidative activity of column chromatographic fractions obtained from brewed coffee was investigated to find antioxidants and to assess the benefit of coffee drinking. The dichloromethane extract inhibited hexanal oxidation by 100 and 50% for 15 days and 30 days, respectively, at the level of 5 microg/mL. A GC/MS analysis of fractions, which exhibited oxidative activity, revealed the presence of antioxidative heterocyclic compounds including furans, pyrroles, and maltol. The residual aqueous solution exhibited slight antioxidative activity. The inhibitory activity (%) of the seven fractions from an aqueous solution toward malonaldehde formation from lipid oxidation ranged from 10 to 90 at a level of 300 microg/mL. The results indicate that brewed coffee contains many antioxidants and consumption of antioxidant-rich brewed coffee may inhibit diseases caused by oxidative damages. PMID:14759154

  6. Antifungal activity of silver nanoparticles obtained by green synthesis.

    PubMed

    Mallmann, Eduardo José J; Cunha, Francisco Afrânio; Castro, Bruno N M F; Maciel, Auberson Martins; Menezes, Everardo Albuquerque; Fechine, Pierre Basílio Almeida

    2015-01-01

    Silver nanoparticles (AgNPs) are metal structures at the nanoscale. AgNPs have exhibited antimicrobial activities against fungi and bacteria; however synthesis of AgNPs can generate toxic waste during the reaction process. Accordingly, new routes using non-toxic compounds have been researched. The proposal of the present study was to synthesize AgNPs using ribose as a reducing agent and sodium dodecyl sulfate (SDS) as a stabilizer. The antifungal activity of these particles against C. albicans and C. tropicalis was also evaluated. Stable nanoparticles 12.5 ± 4.9 nm (mean ± SD) in size were obtained, which showed high activity against Candida spp. and could represent an alternative for fungal infection treatment. PMID:25923897

  7. ANTIFUNGAL ACTIVITY OF SILVER NANOPARTICLES OBTAINED BY GREEN SYNTHESIS

    PubMed Central

    MALLMANN, Eduardo José J.; CUNHA, Francisco Afrânio; CASTRO, Bruno N.M.F.; MACIEL, Auberson Martins; MENEZES, Everardo Albuquerque; FECHINE, Pierre Basílio Almeida

    2015-01-01

    Silver nanoparticles (AgNPs) are metal structures at the nanoscale. AgNPs have exhibited antimicrobial activities against fungi and bacteria; however synthesis of AgNPs can generate toxic waste during the reaction process. Accordingly, new routes using non-toxic compounds have been researched. The proposal of the present study was to synthesize AgNPs using ribose as a reducing agent and sodium dodecyl sulfate (SDS) as a stabilizer. The antifungal activity of these particles against C. albicans and C. tropicalis was also evaluated. Stable nanoparticles 12.5 ± 4.9 nm (mean ± SD) in size were obtained, which showed high activity against Candida spp. and could represent an alternative for fungal infection treatment. PMID:25923897

  8. Photocatalytic activity of titania fibers obtained by electrospinning

    SciTech Connect

    Alves, A.K. Berutti, F.A.; Clemens, F.J.; Graule, T.; Bergmann, C.P.

    2009-02-04

    Composite fibers of polyvinyl pyrrolidone and titanium isopropoxide were prepared in this study using the electrospinning technique. Titanium oxide fibers were obtained after subsequent heat treatment at high temperatures. The photocatalytic activity of these fibers is reported herein. The fibers were characterized using the BET model, thermogravimetry, X-ray diffraction, and scanning electron microscopy. The photocatalytic activity of the titania fibers was investigated using ultraviolet-visible absorbance by following the photooxidative decomposition of methylene blue in comparison to the reference TiO{sub 2} powder Degussa P25. The temperature of heat treatment, the crystalline structure, and the surface area affected the physical and chemical properties of the as-synthesized titania fibers. Increasing the temperature of heat treatment resulted in a decrease in both the fraction of anatase phase and the surface area, thereby leading to reduced photocatalytic activity.

  9. Concentration profiles near an activated enzyme.

    PubMed

    Park, Soohyung; Agmon, Noam

    2008-09-25

    When a resting enzyme is activated, substrate concentration profile evolves in its vicinity, ultimately tending to steady state. We use modern theories for many-body effects on diffusion-influenced reactions to derive approximate analytical expressions for the steady-state profile and the Laplace transform of the transient concentration profiles. These show excellent agreement with accurate many-particle Brownian-dynamics simulations for the Michaelis-Menten kinetics. The steady-state profile has a hyperbolic dependence on the distance of the substrate from the enzyme, albeit with a prefactor containing the complexity of the many-body effects. These are most conspicuous for the substrate concentration at the surface of the enzyme. It shows an interesting transition as a function of the enzyme turnover rate. When it is high, the contact concentration decays monotonically to steady state. However, for slow turnover it is nonmonotonic, showing a minimum due to reversible substrate binding, then a maximum due to diffusion of new substrate toward the enzyme, and finally decay to steady state. Under certain conditions one can obtain a good estimate for the critical value of the turnover rate constant at the transition.

  10. ANTIRADICAL AND ANTIMICROBIAL ACTIVITY OF PHENOLIC FRACTIONS OBTAINED FROM HONEYS.

    PubMed

    Mazol, Irena; Sroka, Zbigniew; Sowa, Alina; Ostrowska, Anna; Dryś, Andrzej; Gamian, Andrzej

    2016-01-01

    Honey is a natural product consisting of multiple components which determine its dietary and medicinal properties. In this work there were studied methanol fractions obtained from seven honeys from Lower Silesia (Poland) collected in different seasons of three successive years. Melissopalynologic studies revealed that two of them were polyfloral, and five were classified as monofloral (two buckwheat and three rapes). The amount of phenolic compounds in honeys varied from 0.09 to 0.38 mg per g of honey. Honeys harvested in 2010 were the richest in phenolic compounds and especially rich was buckwheat honey, comparing to 2011- 2012. Determination of antioxidant potential with the DPPH radical revealed that the strongest antiradical activity was exhibited by extracts obtained from polyfloral (1.22 TAU(515/mg)) and buckwheat (1.06 TAU(515lmg)) honeys, while the highest number of antiradical units was observed for rape honey (3.64 TAU(515/g)). Polyphenolic fractions exhibited various bactericidal activities against Klebsiella pneumoniae and Staphylococcus aureus and weak or no activity was observed against Pseudomonas aeruginosa. PMID:27180430

  11. Non-Newtonian flow between concentric cylinders calculated from thermophysical properties obtained from simulations

    SciTech Connect

    Narayan, A.P.; Rainwater, J.C.; Hanley, H.J.M. |

    1995-03-01

    A study of the Weissenberg effect (rod climbing in a stirred system) based on nonequilibrium molecular dynamics (NEMD) is reported. Simulation results from a soft-sphere fluid are used to obtain a self-consistent free-surface profile of the fluid of finite compressibility undergoing Couette flow between concentric cylinders. A numerical procedure is then applied to calculate the height profile for a hypothetical fluid with thermophysical properties of the soft-sphere liquid and of a dense colloidal suspension. The height profile calculated is identified with shear thickening and the forms of the viscometric functions. The maximum climb occurs between the cylinders rather than at the inner cylinder.

  12. Analysis of liquid-solids suspension velocities and concentrations obtained by NMR imaging

    SciTech Connect

    Ding, J.; Lyczkowski, R.W.; Sha, W.T. ); Altobelli, S.A.; Fukushima, E. )

    1992-09-01

    COMMIX-M, a three-dimensional transient and steady-state computer program written in Cartesian and cylindrical coordinates, has been developed by Argonne National Laboratory. This computer program is capable of analyzing multiphase flow and heat transfer and utilizes the separate phases model wherein each phase has its own mass, momentum, and energy equations. This computer program is in its early stages of development for application to test various interphase interaction models and to predict design and processing of dense fluid-solids suspension systems. COMMIX-M contains preliminary constitutive relationships for interfacial drag, solids viscosities and stresses to describe the solids rheology, and shear lift forces from the literature. Also included is a solids partial slip boundary condition to allow non-zero tangential velocity at the tube walls. Analyses of some of the steady-state, fully-developed isothermal carrier fluid velocity and solids concentration data of Altobelli et al. and Sinton and Chow are presented. These experimental data obtained using three-dimensional time-of-flight nuclear magnetic (NMR) imaging techniques were carefully performed and represent some of the best available open literature data of their kind. NMR imaging offers powerful techniques to non-intrusively determine three-dimensional time-dependent velocity and concentration fields to assist development and validation of the constitutive models and the computer programs describing concentrated suspensions. Analyses of these NMR data, together with comparisons of computed and measured concentration and velocity profiles provide some insights into the mechanisms governing the observed phenomena. Recommendations for future research are given. To the authors' knowledge, these are the first such comparisons of theory and experiment.

  13. Analysis of liquid-solids suspension velocities and concentrations obtained by NMR imaging

    SciTech Connect

    Ding, J.; Lyczkowski, R.W.; Sha, W.T.; Altobelli, S.A.; Fukushima, E.

    1992-09-01

    COMMIX-M, a three-dimensional transient and steady-state computer program written in Cartesian and cylindrical coordinates, has been developed by Argonne National Laboratory. This computer program is capable of analyzing multiphase flow and heat transfer and utilizes the separate phases model wherein each phase has its own mass, momentum, and energy equations. This computer program is in its early stages of development for application to test various interphase interaction models and to predict design and processing of dense fluid-solids suspension systems. COMMIX-M contains preliminary constitutive relationships for interfacial drag, solids viscosities and stresses to describe the solids rheology, and shear lift forces from the literature. Also included is a solids partial slip boundary condition to allow non-zero tangential velocity at the tube walls. Analyses of some of the steady-state, fully-developed isothermal carrier fluid velocity and solids concentration data of Altobelli et al. and Sinton and Chow are presented. These experimental data obtained using three-dimensional time-of-flight nuclear magnetic (NMR) imaging techniques were carefully performed and represent some of the best available open literature data of their kind. NMR imaging offers powerful techniques to non-intrusively determine three-dimensional time-dependent velocity and concentration fields to assist development and validation of the constitutive models and the computer programs describing concentrated suspensions. Analyses of these NMR data, together with comparisons of computed and measured concentration and velocity profiles provide some insights into the mechanisms governing the observed phenomena. Recommendations for future research are given. To the authors` knowledge, these are the first such comparisons of theory and experiment.

  14. In-line filtration of platelet concentrates obtained with the Omnix blood cell separator.

    PubMed

    Moog, R; Müller, N; Nieper, A

    1995-12-01

    The quality of platelet concentrates (PC) obtained with the blood cell separator Omnix was investigated before and after in-line filtration. PC were filtered 2h (protocol A) and 4 h (protocol B) after the termination of apheresis. Platelet (PLT) yield after filtration was similar in both protocols (median 3.7 vs. 3.4 x 10(11)). Median white blood cell (WBC) contamination after leucocyte depletion was 0.07 x 10(6) (range 0.02-3.27 x 10(6)) in protocol A and 0.06 x 10(6) (range 0.02-2.1 x 10(6)) in protocol B. Glucose, lactate, lactate dehydrogenase, morphology score and pH value were not statistically different before and after filtration in both protocols. We conclude that in-line filtration results in sufficient leucocyte depletion of the PC. The prefiltration storage time did not influence the studied parameters of product quality. PMID:8646295

  15. Structural and Morphological Features of Concentric Iron Oxide/Carbon Nanotubes Obtained from Phospholipids

    SciTech Connect

    Yu, Min; Howe, Jane Y; Jeong, Kyunghoon; Shim, Inbo; Kim, Woochul; Kim, Chulsung; Ahn, Jaepyoung; Lee, Jaegab; Urban, Mark W.

    2010-01-01

    Biologically active 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC{sub 8,9}PC) nanotube-forming phospholipids (PLs) have been utilized as templates to prepare ferromagnetic nanotubes (FMNTs). Combining X-ray diffraction (XRD), selected area electron diffraction (SAD), high-resolution transmission electron microscopy (HRTEM), Raman, and Moessbauer spectroscopy measurements, FMNTs morphological features and chemical composition were determined. These studies showed that FMNTs consist of iron oxide/carbon/iron oxide concentric nanotubes with the amorphous carbon phase sandwiched between two iron oxide layers. The iron oxide phase consists of nanocrystalline magnetite (Fe{sub 3}O{sub 4}) which coexist as tetrahedral Fe{sup 3+} and octahedral Fe{sup 2.5+} sites containing minute quantities of hematite ({alpha}-Fe{sub 2}O{sub 3}) phase. The carbon phase consists of amorphous carbon forming an amorphous carbon nanotube (ACNT). Magnetic measurements showed that saturation magnetization (M{sub s}) of FMNTs is 79 emu/g, but upon removal of the iron oxide outer and inner layers, ACNTs become paramagnetic. The electrical resistivity ({rho}) of single FMNT is 3.3 x 10{sup -2} {Omega} {center_dot} m, which decreases to 5.06 x 10{sup -4} {Omega} {center_dot} m for ACNT. These magneto-electric properties can be easily tailored, depending upon desired applications and needs.

  16. Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture.

    PubMed

    Barboza, Thiago José de Souza; Ferreira, Andréa Fonseca; Ignacio, Ana Claudia de Paula Rosa; Albarello, Norma

    2015-01-01

    Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time. PMID:26413061

  17. Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture.

    PubMed

    Barboza, Thiago José de Souza; Ferreira, Andréa Fonseca; Ignacio, Ana Claudia de Paula Rosa; Albarello, Norma

    2015-01-01

    Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.

  18. Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

    PubMed Central

    de Souza Barboza, Thiago José; Ferreira, Andréa Fonseca; de Paula Rosa Ignacio, Ana Claudia; Albarello, Norma

    2015-01-01

    Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time. PMID:26413061

  19. Antioxidant activity of extracts obtained from residues of different oilseeds.

    PubMed

    Matthäus, B

    2002-06-01

    Residues of the oil-extracting process of oilseeds contain bioactive substances such as phenolic compounds, which could be used as natural antioxidants for the protection of fats and oils against oxidative deterioration. Thus, the extraction of such constituents from residual material can be considered to contribute to the added value of these residues, which could justify their isolation. In the present work the fat-free residues of eight different oilseeds whose oils are usable for nutritional applications, and also as renewable resources, were extracted with 70% methanol, 70% acetone, water, and ethyl acetate/water, respectively. The resulting extracts were investigated regarding their content of total phenolic compounds by the Folin-Ciocalteau assay, sinapine, flavanoids, and the UV-absorption spectra. Further, the antioxidant activity of the extracts was characterized by the DPPH method, the beta-carotene-linoleic acid assay, and ESR investigations. The fat-free residues of the different oilseeds contained considerable amounts of extractable substances. The yields decreased with decreasing polarity of the solvent in the order water, 70% methanol, 70% acetone, and ethyl acetate. The ratio of total phenolic compounds to the extractable compounds ranged from 3 to 19%. There was no significant correlation between the amount of total extractable compounds and the total phenolic compounds (p < 0.001). All extracts showed remarkable antioxidant activities determined with the different methods. The effects depended strongly on the solvent used for the extraction as well as on the extracted residue. A correlation between the methods used for the characterization of the antioxidant activity and the composition of the residues could not be shown.

  20. Stratospheric HBr concentration profile obtained from far-infrared emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Nolt, I. G.; Ade, P. A. R.; Alboni, F.; Carli, B.; Carlotti, M.; Cortesi, U.; Epifani, M.; Griffin, M. J.; Hamilton, P. A.; Lee, C.; Lepri, G.; Mencaraglia, F.; Murray, A. G.; Park, J. H.; Park, K.; Raspollini, P.; Ridolfi, M.; Vanek, M. D.

    Hydrogen bromide (HBr) is the principal bromine sink species for the ozone loss chemistry induced by bromine-containing gases in the stratosphere. We report a 1994 balloon-based measurement of the daytime stratospheric HBr profile between 20 and 36.5 km altitude. The average concentration result of 1.31±0.39 parts per trillion in volume (pptv) and an analysis for the concentration versus altitude profile are consistent with previously reported measurements. These results strengthen the evidence for a significantly higher HBr concentration than that predicted by current photochemical models which, on the basis of recent kinetics results, do not include significant HBr production by the reaction branch, BrO + HO2 → HBr + O3.

  1. Therapeutic serum phenobarbital concentrations obtained using chronic transdermal administration of phenobarbital in healthy cats.

    PubMed

    Delamaide Gasper, Joy A; Barnes Heller, Heidi L; Robertson, Michelle; Trepanier, Lauren A

    2015-04-01

    Seizures are a common cause of neurologic disease, and phenobarbital (PB) is the most commonly used antiepileptic drug. Chronic oral dosing can be challenging for cat owners, leading to poor compliance. The purpose of this study was to determine if the transdermal administration of PB could achieve serum PB concentrations of between 15 and 45 μg/ml in healthy cats. Nineteen healthy cats were enrolled in three groups. Transdermal PB in pluronic lecithin organogel (PLO) was applied to the pinnae for 14 days at a dosage of 3 mg/kg q12h in group 1 (n = 6 cats) and 9 mg/kg q12h in group 2 (n = 7 cats). Transdermal PB in Lipoderm Activemax was similarly applied at 9 mg/kg q12h for 14 days in group 3 (n = 6 cats). Steady-state serum PB concentrations were measured at trough, and at 2, 4 and 6 h after the morning dose on day 15. In group 1, median concentrations ranged from 6.0-7.5 μg/ml throughout the day (observed range 0-11 μg/ml). Group 2 median concentrations were 26.0 μg/ml (observed range 18.0-37.0 μg/ml). For group 3, median concentrations ranged from 15.0-17.0 μg/ml throughout the day (range 5-29 μg/ml). Side effects were mild. One cat was withdrawn from group 2 owing to ataxia and sedation. These results show therapeutic serum PB concentrations can be achieved in cats following chronic transdermal administration of PB in PLO at a dosage of 9 mg/kg q12h. More individual variation was noted using Lipoderm Activemax. Transdermal administration may be an alternative for cats that are difficult to medicate orally.

  2. Photovoltaic concentrator assembly with optically active cover

    DOEpatents

    Plesniak, Adam P

    2014-01-21

    A photovoltaic concentrator assembly that includes a housing that defines an internal volume and includes a rim, wherein the rim defines an opening into the internal volume, a photovoltaic cell positioned in the internal volume, and an optical element that includes an optically active body and a flange extending outward from the body, wherein the flange is sealingly engaged with the rim of the housing to enclose the internal volume.

  3. Scale-up of the process to obtain functional ingredients based in plasma protein concentrates from porcine blood.

    PubMed

    Parés, Dolors; Toldrà, Mònica; Saguer, Elena; Carretero, Carmen

    2014-01-01

    The feasibility of a scaled-up process to obtain two protein concentrates from porcine blood plasma, i.e. serum and albumin, for use as functional food ingredients was assessed. The process consisted of fractionating plasma proteins by salting out, concentrating and purifying fractions by means of membrane technology, and subsequently dehydrating through spray-drying. The fractionation process allowed a good isolation of the desired proteins, which were then concentrated and desalted in a tangential flow filtration (TFF) process combining ultra and diafiltration. Purification, pre-concentration and dehydration were successfully achieved. The functional properties of dehydrated serum and albumin were determined. As compared to the same hemoderivatives obtained by a lab-scale production system, serum maintained the gelling properties; albumin exhibited similar foaming properties; and both serum and albumin concentrates showed slightly improved emulsifying properties. PMID:23927918

  4. Chemical and functional properties of fibre concentrates obtained from by-products of coconut kernel.

    PubMed

    Yalegama, L L W C; Nedra Karunaratne, D; Sivakanesan, Ramiah; Jayasekara, Chitrangani

    2013-11-01

    The coconut kernel residues obtained after extraction of coconut milk (MR) and virgin coconut oil (VOR) were analysed for their potential as dietary fibres. VOR was defatted and treated chemically using three solvent systems to isolate coconut cell wall polysaccharides (CCWP). Nutritional composition of VOR, MR and CCWPs indicated that crude fibre, neutral detergent fibre, acid detergent fibre and hemicelluloses contents were higher in CCWPs than in VOR and MR. MR contained a notably higher content of fat than VOR and CCWPs. The oil holding capacity, water holding capacity and swelling capacity were also higher in CCWPs than in VOR and MR. All the isolates and MR and VOR had high metal binding capacities. The CCWPs when compared with commercially available fibre isolates, indicated improved dietary fibre properties. These results show that chemical treatment of coconut kernel by-products can enhance the performance of dietary fibre to yield a better product.

  5. Chemical and functional properties of fibre concentrates obtained from by-products of coconut kernel.

    PubMed

    Yalegama, L L W C; Nedra Karunaratne, D; Sivakanesan, Ramiah; Jayasekara, Chitrangani

    2013-11-01

    The coconut kernel residues obtained after extraction of coconut milk (MR) and virgin coconut oil (VOR) were analysed for their potential as dietary fibres. VOR was defatted and treated chemically using three solvent systems to isolate coconut cell wall polysaccharides (CCWP). Nutritional composition of VOR, MR and CCWPs indicated that crude fibre, neutral detergent fibre, acid detergent fibre and hemicelluloses contents were higher in CCWPs than in VOR and MR. MR contained a notably higher content of fat than VOR and CCWPs. The oil holding capacity, water holding capacity and swelling capacity were also higher in CCWPs than in VOR and MR. All the isolates and MR and VOR had high metal binding capacities. The CCWPs when compared with commercially available fibre isolates, indicated improved dietary fibre properties. These results show that chemical treatment of coconut kernel by-products can enhance the performance of dietary fibre to yield a better product. PMID:23768337

  6. Concentration and temperature effects on ovostatin activity

    NASA Technical Reports Server (NTRS)

    Moriarity, Debra M.

    1994-01-01

    Light scattering experiments performed at Mississippi State University using MSFC ovostatin preparations indicated that at low ovostatin concentrations, below 0.2 mg/ml, the protein was dissociating from a tetramer into dimers. Since the proposed mechanism of action involved the tetrameric form of the protein, we hypothesized that perhaps under the conditions of our assays at various O/T ratios the ovostatin was becoming dissociated into an inactive dimer. To examine this possibility we assayed the ovostatin activity as a function of ovostatin concentration and of temperature of the assay. Data are presented that show the results of these assays at 23 C, 30 C, 37 C and 42 C respectively. The data are highly suggestive that there is a decrease in ovostatin activity as the concentration of the protein falls below 0.06 mg/ml. This may not be of any physiological importance, however, since the concentration of ovostatin in the egg is about 0.5 mg/ml. Curiously, the dissociation of the tetramer into dimers does not show a significant temperature dependence as would be expected for an equilibrium reaction. Whether this is in fact the case, or whether the differences are so small as to not be discerned from the current data remains to be seen. Another aspect to consider is that in the egg the primary role of the ovostatin may or may not be as a protease inhibitor. Although the inhibition of collagenase by ovostatin may be an important aspect of embryogenesis, it is also possible that it functions as a binding protein for some substance. In this regard, all ovostatin preparations from MSFC have shown an approximately 88,000 MW protein associated with the ovostatin. The identity of this protein is not currently known and may be the subject of future studies.

  7. Activated carbons obtained from sewage sludge by chemical activation: gas-phase environmental applications.

    PubMed

    Boualem, T; Debab, A; Martínez de Yuso, A; Izquierdo, M T

    2014-07-01

    The objective of this study was to evaluate the adsorption capacity for toluene and SO2 of low cost activated carbons prepared from sewage sludge by chemical activation at different impregnation ratios. Samples were characterized by proximate and ultimate analyses, thermogravimetry, infrared spectroscopy and N2 adsorption. Because of the low carbon content of the raw material, the development of porosity in the activated carbons was mainly of a mesoporous nature, with surface areas lower than 300 m(2)/g. The study of gas-phase applications for activated carbons from sewage sludge was carried out using both an organic and an inorganic compound in order to screen for possible applications. Toluene adsorption capacity at saturation was around 280 mg/g, which is a good level of performance given the high ash content of the activated carbons. However, dynamic experiments at low toluene concentration presented diffusion problems resulting from low porosity development. SO2 adsorption capacity is associated with average micropore size, which can be controlled by the impregnation ratio used to prepare the activated carbons.

  8. Interlaboratory comparison on 137Cs activity concentration in fume dust

    NASA Astrophysics Data System (ADS)

    Tzika, Faidra; Hult, Mikael; Burda, Oleksiy; Arnold, Dirk; Sibbens, Goedele; Caro Marroyo, Belén; Gómez-Mancebo, Maria Belén; Peyrés, Virginia; Moser, Hannah; Ferreux, Laurent; Šolc, Jaroslav; Dryák, Pavel; Fazio, Aldo; Luca, Aurelian; Vodenik, Branko; Reis, Mario; Tyminski, Zbigniew; Klemola, Seppo

    2015-11-01

    A comparison was conducted, between 11 European National Metrology Institutes and EC-JRC, on measurement of 137Cs activity concentration in fume dust. As test material an activity standard produced from real contaminated fume dust was used. The standard material consisted of 13 cylindrical samples of compressed fume dust. The material contained 137Cs and 60Co of reference activity concentrations of (9.72±0.10) Bq/g and (0.450±0.018) Bq/g, respectively, for the reference date of 1 June 2013, determined using the comparison results. The organization and results of the intercomparison, as well as the process of obtaining reliable reference values are presented.

  9. Antimicrobial activity of Brazilian copaiba oils obtained from different species of the Copaifera genus.

    PubMed

    Santos, Adriana Oliveira Dos; Ueda-Nakamura, Tânia; Dias Filho, Benedito Prado; Veiga Junior, Valdir F; Pinto, Angelo C; Nakamura, Celso Vataru

    2008-05-01

    The antimicrobial activity of copaiba oils was tested against Gram-positive and Gram-negative bacteria, yeast, and dermatophytes. Oils obtained from Copaifera martii, Copaifera officinalis, and Copaifera reticulata (collected in the state of Acre) were active against Gram-positive species (Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Bacillus subtilis, and Enterococcus faecalis) with minimum inhibitory concentrations ranging from 31.3-62.5 microg/ml. The oils showed bactericidal activity, decreasing the viability of these Gram-positive bacteria within 3 h. Moderate activity was observed against dermatophyte fungi (Trichophyton rubrum and Microsporum canis). The oils showed no activity against Gram-negative bacteria and yeast. Scannning electron microscopy of S. aureus treated with resin oil from C. martii revealed lysis of the bacteria, causing cellular agglomerates. Transmission electron microscopy revealed disruption and damage to the cell wall, resulting in the release of cytoplasmic compounds, alterations in morphology, and a decrease in cell volume, indicating that copaiba oil may affect the cell wall. PMID:18545856

  10. Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons.

    PubMed

    Cardoso, Bruna Muller; de Mello, Tatiane França Perles; Lopes, Sara Negrão; Demarchi, Izabel Galhardo; Lera, Daniele Stefani Lopes; Pedroso, Raíssa Bocchi; Cortez, Diogenes Aparício; Gazim, Zilda Cristiani; Aristides, Sandra Mara Alessi; Silveira, Thais Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana

    2015-12-01

    The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases.

  11. Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons.

    PubMed

    Cardoso, Bruna Muller; de Mello, Tatiane França Perles; Lopes, Sara Negrão; Demarchi, Izabel Galhardo; Lera, Daniele Stefani Lopes; Pedroso, Raíssa Bocchi; Cortez, Diogenes Aparício; Gazim, Zilda Cristiani; Aristides, Sandra Mara Alessi; Silveira, Thais Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana

    2015-12-01

    The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases. PMID:26602873

  12. Antileishmanial activity of the essential oil from Tetradenia riparia obtained in different seasons

    PubMed Central

    Cardoso, Bruna Muller; de Mello, Tatiane França Perles; Lopes, Sara Negrão; Demarchi, Izabel Galhardo; Lera, Daniele Stefani Lopes; Pedroso, Raíssa Bocchi; Cortez, Diogenes Aparício; Gazim, Zilda Cristiani; Aristides, Sandra Mara Alessi; Silveira, Thais Gomes Verzignassi; Lonardoni, Maria Valdrinez Campana

    2015-01-01

    The herbaceous shrub Tetradenia riparia has been traditionally used to treat inflammatory and infectious diseases. Recently, a study showed that T. riparia essential oil (TrEO) obtained in summer has antileishmanial effects, although these results could be influenced by seasonal variation. This study evaluated the activity of the TrEO obtained in different seasons against Leishmania (Leishmania) amazonensis, in vitro and in vivo. The compounds in the TrEO were analysed by gas chromatography-mass spectrometry; terpenoids were present and oxygenated sesquiterpenes were the majority compounds (55.28%). The cytotoxicity and nitric oxide (NO) production were also tested after TrEO treatment. The TrEO from all seasons showed a 50% growth inhibitory concentration for promastigotes of about 15 ng/mL; at 30 ng/mL and 3 ng/mL, the TrEO reduced intracellular amastigote infection, independently of season. The TrEO from plants harvested in summer had the highest 50% cytotoxic concentration, 1,476 ng/mL for J774.A1 macrophages, and in spring (90.94 ng/mL) for murine macrophages. NO production did not change in samples of the TrEO from different seasons. The antileishmanial effect in vivo consisted of a reduction of the parasite load in the spleen. These results suggest that the TrEO has potential effects on L. (L.) amazonensis, consonant with its traditional use to treat parasitic diseases. PMID:26602873

  13. Convulsant activity and neurochemical alterations induced by a fraction obtained from fruit Averrhoa carambola (Oxalidaceae: Geraniales).

    PubMed

    Carolino, Ruither O G; Beleboni, Renê O; Pizzo, Andrea B; Vecchio, Flavio Del; Garcia-Cairasco, Norberto; Moyses-Neto, Miguel; Santos, Wagner F Dos; Coutinho-Netto, Joaquim

    2005-06-01

    We obtained a neurotoxic fraction (AcTx) from star fruit (Averrhoa carambola) and studied its effects on GABAergic and glutamatergic transmission systems. AcTx had no effect on GABA/glutamate uptake or release, or on glutamate binding. However, it specifically inhibited GABA binding in a concentration-dependent manner (IC(50)=0.89muM). Video-electroencephalogram recordings demonstrated that following cortical administration of AcTx, animals showed behavioral changes, including tonic-clonic seizures, evolving into status epilepticus, accompanied by cortical epileptiform activity. Chemical characterization of AcTx showed that this compound is a nonproteic molecule with a molecular weight less than 500, differing from oxalic acid. This neurotoxic fraction of star fruit may be considered a new tool for neurochemical and neuroethological research.

  14. Method for obtaining silver nanoparticle concentrations within a porous medium via synchrotron X-ray computed microtomography.

    PubMed

    Molnar, Ian L; Willson, Clinton S; O'Carroll, Denis M; Rivers, Mark L; Gerhard, Jason I

    2014-01-21

    Attempts at understanding nanoparticle fate and transport in the subsurface environment are currently hindered by an inability to quantify nanoparticle behavior at the pore scale (within and between pores) within realistic pore networks. This paper is the first to present a method for high resolution quantification of silver nanoparticle (nAg) concentrations within porous media under controlled experimental conditions. This method makes it possible to extract silver nanoparticle concentrations within individual pores in static and quasi-dynamic (i.e., transport) systems. Quantification is achieved by employing absorption-edge synchrotron X-ray computed microtomography (SXCMT) and an extension of the Beer-Lambert law. Three-dimensional maps of X-ray mass linear attenuation are converted to SXCMT-determined nAg concentration and are found to closely match the concentrations determined by ICP analysis. In addition, factors affecting the quality of the SXCMT-determined results are investigated: 1) The acquisition of an additional above-edge data set reduced the standard deviation of SXCMT-determined concentrations; 2) X-ray refraction at the grain/water interface artificially depresses the SXCMT-determined concentrations within 18.1 μm of a grain surface; 3) By treating the approximately 20 × 10(6) voxels within each data set statistically (i.e., averaging), a high level of confidence in the SXCMT-determined mean concentrations can be obtained. This novel method provides the means to examine a wide range of properties related to nanoparticle transport in controlled laboratory porous medium experiments. PMID:24354304

  15. Effect of different K+ concentrations on Cryptococcus neoformans phenoloxidase activity.

    PubMed

    Vidotto, Valerio; Defina, Nicola; Pugliese, Agostino; Aoki, Shigeji; Nakamura, Kenjrou; Takeo, Kanjj

    2002-01-01

    Melanin synthesis in Cryptococcus neoformans, catalyzed by phenoloxidase activity, is one of the oldest virulence factors known. However, until now, the relationship between melanin production in C. neoformans and its virulence has been poorly understood. Among different chemical compounds only Fe3+ and Cu2+ cations enhance the phenoloxidase activity in C. neoformans. A few reports in the literature describe the influence of different cations on C. neoformans phenoloxidase activity, excluding iron. In this study, 13 C. neoformans strains isolated from AIDS patients and 7 from bird droppings (B.D.), were examined in order to clarify the effect of different K+ concentrations on phenoloxidase activity. A new solid and liquid caffeic acid minimal synthetic medium (MSM-CAF) containing only caffeic acid and ferric citrate with different potassium concentrations was used to evaluate C. neoformans phenoloxidase activity. In the MSM-CAF solid medium the degree of brown pigmentation on the agar plates was read on days 1, 2 and 3 of incubation, and the pigmentation of the C. neoformans strains was classed into 5 categories. The brown pigment of the liquid MSM-CAF test tubes were checked after 24 hours of incubation by measuring the optical density (O.D.) at 480 nm. Three C. neoformans AIDS and B.D. strains, randomly chosen, were tested for phenoloxidase activity, according to the modified protocols of Polacheck et al., Torres-Guerrero et al. and Rhodes. According to the results obtained, it has been observed that K+ does not activate the phenoloxidase activity in the C. neoformans AIDS and B.D. strains. In particular, with an increase in potassium concentrations in the MSM-CAF solid and liquid medium, there was a corresponding inhibition of the phenoloxidase activity on both the C. neoformans AIDS and B.D. strains. PMID:12749580

  16. How long should a system be observed to obtain reliable concentration estimates from the measurement of fluctuations?

    PubMed

    Pérez Ipiña, Emiliano; Ponce Dawson, Silvina

    2014-12-01

    The interior of cells is a highly fluctuating environment. Fluctuations set limits to the accuracy with which endogenous processes can occur. The physical principles that rule these limits also affect the experimental quantification of biophysical parameters in situ. The characterization of fluctuations, on the other hand, provides a way to quantify biophysical parameters. But as with any random process, enough data has to be collected to achieve a reliable quantitative description. In this article we study the accuracy with which intracellular concentrations can be estimated using fluorescence correlation spectroscopy. We show that, when the observed molecules interact with immobile species or experience other restrictions to their movement, the hypotheses commonly used to estimate concentrations are no longer valid. The interactions with immobile sites reduce the fluorescence variance by a finite amount. The time that is necessary to obtain an accurate concentration estimate, on the other hand, is hundreds of times larger than the slowest correlation time and is much larger when the sites move slowly than when they are immobile. Our analysis is applicable to other related techniques and it also sheds light on the way in which effector concentrations are read by target molecules in cells. PMID:25468346

  17. Hypertensive factor: calcium stimulatory activity obtained from different tissues and animal species.

    PubMed

    Wright, G L; Huang, B S; Johnson, P J; McCumbee, W D

    1988-10-01

    It was recently shown that a peptide (hypertensive factor, HF) isolated from erythrocyte hemolysates from spontaneously hypertensive rats induced a prolonged elevation of blood pressure in normotensive rats. In addition, the peptide produced a marked stimulation of the in vitro uptake of lanthanum-resistant calcium by the aortae and enhanced the contractile response of aortic rings to constrictor agents. The present report describes findings of calcium stimulatory activity, enhancement of contractile function, or pressor activity in extracts of homogenates from several tissues of the rat and from erythrocyte hemolysates of several mammalian species. Significant stimulation of calcium uptake in aortic rings was obtained with preparations from rat brain, liver, and kidney. The activity per weight of tissue was similar for brain and kidney (approximately 2 units/g), while liver exhibited somewhat higher concentrations (4 units/g). The diffusate of cardiac tissue did not significantly alter in vitro calcium uptake by aortae. The injection of the cardiac and liver diffusates into normotensive Wistar-Kyoto rats produced slight (10 Torr) (1 Torr = 133.3Pa) and moderate (25 Torr) elevations of blood pressure, respectively. Finally, a peptide purified from homogenates of rat brain by the protocol developed for the purification of HF from erythrocytes was shown to significantly enhance the contractile response of aortic rings to K+ and norepinephrine. Diffusates of erythrocytes from the rat, rabbit, dog, and guinea pig each caused a significant stimulation of calcium uptake and contained approximately the same level of activity (500 units/L of whole blood). Diffusates prepared from outdated human erythrocytes had no significant effect on calcium uptake, whereas those of freshly drawn samples exhibited high levels of activity.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. [Obtaining of bacterial bioluminescent strain Protobacterium phosphoreum B7071 (lux+) for the determination of zinc ion concentration].

    PubMed

    Gruzina, T G; Dybkova, S N; Chekhovskaia, T P; Vember, V V; Zadorozhniaia, A M; Ul'berg, Z R

    2006-01-01

    The transconjugate containing hybrid plasmid (Te(R)Zn(R)lux+) was obtained using the conjugation method on Pseudomonasfragi T2(5) (Te(R)ZnR) strain and bioluminescent strain Protobacterium phosphoreum B7071 (lux+). The expression regulation of lux-genes on the obtained plasmid is carried out by promotor-operational area conjointly with zinc resistance genes. The cells of the obtained genetically modified bacteria have the ability to specific induced luminescence, which is a respond to zinc ions' presence in the measuring medium. It was shown that the cells' bioluminescence intensity of trans-conjugate is linearly dependent on zinc ions' concentration within the range of 1-100 microM, that provides the opportunity of using biosensor as a strain for qualitative and quantitative detection of the metal. The low sensitivity limit of this method is 0.5 microM for the metal. Besides having high sensitivity, the developed lux-biosensor is highly specified. PMID:17147278

  19. Free-radical scavenging activity and antibacterial impact of Greek oregano isolates obtained by SFE.

    PubMed

    Stamenic, Marko; Vulic, Jelena; Djilas, Sonja; Misic, Dusan; Tadic, Vanja; Petrovic, Slobodan; Zizovic, Irena

    2014-12-15

    The antioxidant and antibacterial properties of Greek oregano extracts obtained by fractional supercritical fluid extraction (SFE) with carbon dioxide were investigated and compared with the properties of essential oil obtained by hydrodistillation. According to DPPH, hydroxyl radical and superoxide anion radical scavenging activity assays, the supercritical extracts expressed stronger antioxidant activity comparing to the essential oil. The most effective was the supercritical extract obtained by fractional extraction at 30 MPa and 100°C after the volatile fraction had been extracted at lower pressure. At the same time this extract showed strong antibacterial activity against staphylococci, including MRSA strain, but did not affect Escherichia coli of normal intestinal flora. The essential oil obtained by hydrodistillation showed stronger antibacterial activity against E. coli, Salmonella and Klebsiella pneumoniae, comparing to the supercritical extracts but at the same affected the normal gut flora.

  20. Using a Concentrate of Phenols Obtained from Olive Vegetation Water to Preserve Chilled Food: Two Case Studies

    PubMed Central

    Cardazzo, Barbara; Balzan, Stefania; Carraro, Lisa; Andreani, Andrea Nadia; Taticchi, Agnese; Novelli, Enrico

    2016-01-01

    Phenols are plant metabolites characterised by several interesting bioactive properties such as antioxidant and bactericidal activities. In this study the application of a phenols concentrate (PC) from olive vegetation water to two different fresh products – gilt-head seabream (Sparus aurata) and chicken breast – was described. Products were treated in a bath of PC (22 g/L; chicken breast) or sprayed with two different solutions (L1:0.75 and L2:1.5 mg/mL; seabream) and then stored under refrigeration conditions. The shelf life was monitored through microbiological analyses – quality index method for seabream and a specific sensory index for raw breast. The secondary products of lipid-peroxidation of the chicken breast were determined using the thiobarbituric acid reactive substances (TBARs) test on cooked samples. Multivariate statistical techniques were adopted to investigate the impact of phenols and microbiological data were fitted by DMfit software. In seabream, the levels of PC did not highlight any significant difference on microbiological and sensory features. DMfit models suggested an effect only on H2S producing bacteria with an increased lag phase compared to the control samples (C: 87 h vs L2: 136 h). The results on chicken breast showed that the PC bath clearly modified the growth of Pseudomonas and Enterobacteriaceae. The phenol dipping was effective in limiting lipid-peroxidation (TBARs) after cooking. Treated samples disclosed an increase of shelf life of 2 days. These could be considered as preliminary findings suggesting the use of this concentrate as preservative in some fresh products. PMID:27800444

  1. Development and calibration of a portable radon sampling system for groundwater 222Rn activity concentration measurements.

    PubMed

    Lucas, Fabio de Oliveira; de Oliveira, Igor José Chaves; Ribeiro, Fernando Brenha

    2009-10-01

    The assembling of a system for field sampling and activity concentration measurement of radon dissolved in groundwater is described. Special attention is given in presenting the calibration procedure to obtain the radon activity concentration in groundwater from the raw counting rate registered in a portable scintillation detector and in establishing the precision of the activity concentration measurements. A field procedure was established and the system tested during one year of monthly observations of (222)Rn activity concentration in groundwater drawn from two wells drilled on metamorphic rocks exposed at Eastern São Paulo State, Brazil. The observed mean (222)Rn activity concentrations are 374Bq/dm(3) in one well and about 1275Bq/dm(3) in the other one. In both wells the (222)Rn activity concentrations showed a seasonal variation similar to variations previously reported in the literature for the same region.

  2. Determination of concentration and activity of immobilized enzymes.

    PubMed

    Singh, Priyanka; Morris, Holly; Tivanski, Alexei V; Kohen, Amnon

    2015-09-01

    Methods that directly measure the concentration of surface-immobilized biomolecules are scarce. More commonly, the concentration of the soluble molecule is measured before and after immobilization, and the bound concentration is assessed by elimination, assuming that all bound molecules are active. An assay was developed for measuring the active site concentration, activity, and thereby the catalytic turnover rate (kcat) of an immobilized dihydrofolate reductase as a model system. The new method yielded a similar first-order rate constant, kcat, to that of the same enzyme in solution. The findings indicate that the activity of the immobilized enzyme, when separated from the surface by the DNA spacers, has not been altered. In addition, a new immobilization method that leads to solution-like activity of the enzyme on the surface is described. The approaches developed here for immobilization and for determining the concentration of an immobilized enzyme are general and can be extended to other enzymes, receptors, and antibodies.

  3. Errors in ozone risk assessment using standard conditions for converting ozone concentrations obtained by passive samplers in mountain regions.

    PubMed

    Gerosa, G; Finco, A; Marzuoli, R; Ferretti, M; Gottardini, E

    2012-05-01

    Passive samplers are often employed to measure ozone concentrations in remote areas such as mountain forests. The potential ozone risk for vegetation is then assessed by calculating the AOT40 exposure index (accumulated hourly ozone concentration exceedances above 40 ppb, i.e. AOT40 = Σ([O(3)] - 40)Δt for any hourly ozone concentration [O(3)] > 40 ppb). AOT40 is customary calculated on the basis of ozone concentrations expressed as a volumetric mixing ratio, while lab sheets normally report ozone concentrations from passive samplers in mass units per cubic metre. Concentrations are usually converted from mass units to ppb using a standard conversion factor taking SATP (Standard Ambient Temperature and Pressure) conditions into account. These conditions, however, can vary considerably with elevation. As a consequence, the blanket application of a standard conversion factor may lead to substantial errors in reporting and mapping ozone concentrations and therefore in assessing potential ozone risk in mountain regions. In this paper we carry out a sensitivity analysis of the effects of uncertainties in estimations of air temperature (T) and atmospheric pressure (P) on the concentration conversion factor, and present two examples from two monitoring and mapping exercises carried out in the Italian Alps. We derived P and T at each site from adiabatic lapse rates for temperature and pressure and analysed the magnitude of error in concentration estimations. Results show that the concentration conversion is much more sensitive to uncertainties in P gradient estimation than to air temperature errors. The concentration conversion factor (cf) deviates 5% from the standard transformation at an elevation of 500 m asl. As a consequence, the standard estimated AOT40 at this elevation is about 13% less than the actual value. AOT40 was found to be underestimated by an average between 25% and 34% at typical elevations of mountain forest stands in the Italian Alps when a correct

  4. Determination of antioxidant activity of bioactive peptide fractions obtained from yogurt.

    PubMed

    Aloğlu, H Sanlıdere; Oner, Z

    2011-11-01

    In this study, physicochemical and microbiological properties of traditional and commercial yogurt samples were determined during 4 wk of storage. Proteolytic activity, which occurs during the storage period of yogurt samples, was also determined. Peptide fractions obtained from yogurts were investigated and the effect of proteolysis on peptide release during storage was determined. The antioxidant activities of peptides released from yogurt water-soluble extracts (WSE) and from HPLC fractions were determined by 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. The antioxidant activity of WSE from traditional yogurt was greater than that of WSE from commercial yogurts. In analysis by the ABTS method, mean values increased from 7.697 to 8.739 mM Trolox/g in commercial yogurts, and from 10.115 to 13.182 mM Trolox/g in traditional yogurts during storage. Antioxidant activities of peptides released from HPLC fractions of selected yogurt samples increased 10 to 200 times. In all yogurt samples, the greatest antioxidant activity was shown in the F2 fraction. After further fractionation of yogurt samples, the fractions coded as F2.2, F2.3, F4.3, and F4.4 had the highest antioxidant activity values. Total antioxidant activity of yogurts was low but after purification of peptides by fractionation in HPLC, peptide fractions with high antioxidant activity were obtained.

  5. Fast Centrifugal Partition Chromatography Fractionation of Concentrated Agave (Agave salmiana) Sap to Obtain Saponins with Apoptotic Effect on Colon Cancer Cells.

    PubMed

    Santos-Zea, Liliana; Fajardo-Ramírez, Oscar R; Romo-López, Irasema; Gutiérrez-Uribe, Janet A

    2016-03-01

    Separation of potentially bioactive components from foods and plant extracts is one of the main challenges for their study. Centrifugal partition chromatography has been a successful technique for the screening and identification of molecules with bioactive potential, such as steroidal saponins. Agave is a source of steroidal saponins with anticancer potential, though the activity of these compounds in concentrated agave sap has not been yet explored. In this study, fast centrifugal partition chromatography (FCPC) was used coupled with in vitro tests on HT-29 cells as a screening procedure to identify apoptotic saponins from an acetonic extract of concentrated agave sap. The three most bioactive fractions obtained by FCPC at partition coefficients between 0.23 and 0.4 contained steroidal saponins, predominantly magueyoside b. Flow cytometry analysis determined that the fraction rich in kammogenin and manogenin glycosides induced apoptosis, but when gentrogenin and hecogenin glycosides were also found in the fraction, a necrotic effect was observed. In conclusion, this study provides the evidence that steroidal saponins in concentrated agave sap were potential inductors of apoptosis and that it was possible to separate them using fast centrifugal partition chromatography. PMID:26701355

  6. Fast Centrifugal Partition Chromatography Fractionation of Concentrated Agave (Agave salmiana) Sap to Obtain Saponins with Apoptotic Effect on Colon Cancer Cells.

    PubMed

    Santos-Zea, Liliana; Fajardo-Ramírez, Oscar R; Romo-López, Irasema; Gutiérrez-Uribe, Janet A

    2016-03-01

    Separation of potentially bioactive components from foods and plant extracts is one of the main challenges for their study. Centrifugal partition chromatography has been a successful technique for the screening and identification of molecules with bioactive potential, such as steroidal saponins. Agave is a source of steroidal saponins with anticancer potential, though the activity of these compounds in concentrated agave sap has not been yet explored. In this study, fast centrifugal partition chromatography (FCPC) was used coupled with in vitro tests on HT-29 cells as a screening procedure to identify apoptotic saponins from an acetonic extract of concentrated agave sap. The three most bioactive fractions obtained by FCPC at partition coefficients between 0.23 and 0.4 contained steroidal saponins, predominantly magueyoside b. Flow cytometry analysis determined that the fraction rich in kammogenin and manogenin glycosides induced apoptosis, but when gentrogenin and hecogenin glycosides were also found in the fraction, a necrotic effect was observed. In conclusion, this study provides the evidence that steroidal saponins in concentrated agave sap were potential inductors of apoptosis and that it was possible to separate them using fast centrifugal partition chromatography.

  7. Use of Different Proteases to Obtain Flaxseed Protein Hydrolysates with Antioxidant Activity.

    PubMed

    Karamać, Magdalena; Kosińska-Cagnazzo, Agnieszka; Kulczyk, Anna

    2016-01-01

    The antioxidant activity of flaxseed protein hydrolysates obtained using five different enzymes was evaluated. Proteins were isolated from flaxseed cake and were separately treated with papain, trypsin, pancreatin, Alcalase and Flavourzyme. The degree of hydrolysis (DH) was determined as the percentage of cleaved peptide bonds using a spectrophotometric method with o-phthaldialdehyde. The distribution of the molecular weights (MW) of the hydrolysis products was profiled using Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE) and size exclusion-high performance liquid chromatography (SE-HPLC) separations. The antioxidant activities of the protein isolate and hydrolysates were probed for their radical scavenging activity using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS(•+)) and photochemiluminescence (PCL-ACL) assays, and for their ferric reducing antioxidant power (FRAP) and ability to bind Fe(2+). The hydrolysates were more effective as antioxidants than the protein isolate in all systems. The PCL-ACL values of the hydrolysates ranged from 7.2 to 35.7 μmol Trolox/g. Both the FRAP and ABTS(•+) scavenging activity differed among the hydrolysates to a lower extent, with the ranges of 0.20-0.24 mmol Fe(2+)/g and 0.17-0.22 mmol Trolox/g, respectively. The highest chelating activity (71.5%) was noted for the pancreatin hydrolysate. In general, the hydrolysates obtained using Alcalase and pancreatin had the highest antioxidant activity, even though their DH (15.4% and 29.3%, respectively) and the MW profiles of the peptides varied substantially. The O₂(•-) scavenging activity and the ability to chelate Fe(2+) of the Flavourzyme hydrolysate were lower than those of the Alcalase and pancreatin hydrolysates. Papain was the least effective in releasing the peptides with antioxidant activity. The study showed that the type of enzyme used for flaxseed protein hydrolysis determines the antioxidant activity

  8. Use of Different Proteases to Obtain Flaxseed Protein Hydrolysates with Antioxidant Activity

    PubMed Central

    Karamać, Magdalena; Kosińska-Cagnazzo, Agnieszka; Kulczyk, Anna

    2016-01-01

    The antioxidant activity of flaxseed protein hydrolysates obtained using five different enzymes was evaluated. Proteins were isolated from flaxseed cake and were separately treated with papain, trypsin, pancreatin, Alcalase and Flavourzyme. The degree of hydrolysis (DH) was determined as the percentage of cleaved peptide bonds using a spectrophotometric method with o-phthaldialdehyde. The distribution of the molecular weights (MW) of the hydrolysis products was profiled using Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine-SDS-PAGE) and size exclusion-high performance liquid chromatography (SE-HPLC) separations. The antioxidant activities of the protein isolate and hydrolysates were probed for their radical scavenging activity using 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS•+) and photochemiluminescence (PCL-ACL) assays, and for their ferric reducing antioxidant power (FRAP) and ability to bind Fe2+. The hydrolysates were more effective as antioxidants than the protein isolate in all systems. The PCL-ACL values of the hydrolysates ranged from 7.2 to 35.7 μmol Trolox/g. Both the FRAP and ABTS•+ scavenging activity differed among the hydrolysates to a lower extent, with the ranges of 0.20–0.24 mmol Fe2+/g and 0.17–0.22 mmol Trolox/g, respectively. The highest chelating activity (71.5%) was noted for the pancreatin hydrolysate. In general, the hydrolysates obtained using Alcalase and pancreatin had the highest antioxidant activity, even though their DH (15.4% and 29.3%, respectively) and the MW profiles of the peptides varied substantially. The O2•− scavenging activity and the ability to chelate Fe2+ of the Flavourzyme hydrolysate were lower than those of the Alcalase and pancreatin hydrolysates. Papain was the least effective in releasing the peptides with antioxidant activity. The study showed that the type of enzyme used for flaxseed protein hydrolysis determines the antioxidant activity of

  9. Effects of storage time on total protein and globulin concentrations in bovine fresh frozen plasma obtained for transfusion.

    PubMed

    Proverbio, D; Spada, E; Baggiani, L; Bagnagatti De Giorgi, G; Roggero, N; Belloli, A; Pravettoni, D; Perego, R

    2015-01-01

    To evaluate the effects of storage conditions on total protein (TP) and globulin fractions in fresh frozen bovine plasma units prepared and stored for transfusion, TP and globulin fractions were evaluated in fresh plasma and at 1 month and 6 and 12 months after blood collection in plasma stored at -20°C. Significant differences in concentrations were found in the median concentration of total protein (P=0.0336), between 0 months and 1 month (P=0.0108), 0 and 6 months (P=0.0023), and 0 and 12 months (P=0.0027), in mean concentration (g/dL) of albumin (P=0.0394), between 0 months and 1 month (P=0.0131), 0 and 6 months (P=0.0035), and 0 and 12 months (P=0.0038), and beta-2 fraction (P=0.0401), between 0 and 6 months (P=0.0401) and 0 and 12 months (P=0.0230). This study suggests that total gamma globulin concentration in bovine frozen plasma is stable for 12 months at -20°C. Total protein, ALB, and beta-2 fraction have significantly different concentrations (g/dL) when compared to prestorage. This study has shown IgG protein fraction stability in bovine fresh frozen plasma collected for transfusion; therefore, bovine fresh frozen plasma seems to be suitable for the treatment of hypogammaglobulinemia (failure of passive transfer) in calves when stored for 12 months at -20°C.

  10. Antiproliferative Activity of Polyether Antibiotic--Cinchona Alkaloid Conjugates Obtained via Click Chemistry.

    PubMed

    Skiera, Iwona; Antoszczak, Michał; Trynda, Justyna; Wietrzyk, Joanna; Boratyński, Przemysław; Kacprzak, Karol; Huczyński, Adam

    2015-10-01

    A series of eight new conjugates of salinomycin or monensin and Cinchona alkaloids were obtained by the Cu(I)-catalysed 1,3-dipolar Huisgen cycloaddition (click chemistry) of respective N-propargyl amides of salinomycin or monensin with four different Cinchona alkaloid derived azides. In vitro antiproliferative activity of these conjugates evaluated against three cancer cell lines (LoVo, LoVo/DX, HepG2) showed that four of the compounds exhibited high antiproliferative activity (IC50 below 3.00 μm) and appeared to be less toxic and more selective against normal cells than two standard anticancer drugs.

  11. A CLOSURE STUDY OF AEROSOL MASS CONCENTRATION MEASUREMENTS: COMPARISON OF VALUES OBTAINED WITH FILTERS AND BY DIRECT MEASUREMENTS OF MASS DISTRIBUTIONS. (R826372)

    EPA Science Inventory

    We compare measurements of aerosol mass concentrations obtained gravimetrically using Teflon coated glass fiber filters and by integrating mass distributions measured with the differential mobility analyzer–aerosol particle mass analyzer (DMA–APM) technique (Aero...

  12. Potential data used for validation of concentration statistics obtained using analytical model for conservative transport in an estuary

    NASA Astrophysics Data System (ADS)

    Galesic, Morena; Andricevic, Roko; Divic, Vladimir; Mateus, Marcos; Pinto, Ligia

    2016-04-01

    Coastal areas worldwide are important and sensitive ecosystems. Rivers are considered to be one of the most influential hydrological pathways for the waterborne transport and therefore estuaries are critical areas for a pollution hazard. To describe that hazard, the risk of exceeding the allowed concentration values of the pollution substance in such environment is often used. The analytical model calculates concentration statistics directly from the fundamental advective-diffusion equation for the case of continuous, steady conservative transport with the dominant stream flow mean velocity such is the case of low tide estuaries. Similar analytical models were previously proposed in atmosphere (Sullivan, 2004) and in groundwater (Andricevic, 2008). Knowing the main velocity and initial mass coming from the river, this kind of approach enables one a direct prediction of one-point concentration probability density function (pdf) which is then used to define the risk of exceeding the allowed concentration for certain water body. In this work we investigate how different data can be used for validation of the developed analytical model for conservative transport in an estuary. Two different types of measurement are being conducted at the local river Zrnovnica near city of Split, one measuring velocity and the other measuring salinity and temperature. Velocity data are used as an input to a numerical random walk particle tracking model to calculate the concentration moments. The salinity data are used as inverse proxy substance, hence the concentration moments are calculated directly from the inverse measured values. The results are highly affected by the scale effect, as the analytical model is developed at the point, while both numerical and measured values are smoothed over the grid size and over the sampling volume, respectively. However, the measured salinity, as concentration proxy, proved more resemblance to the concentration moment's shape, while numerical model

  13. Assessment of antiproliferative activity of pectic substances obtained by different extraction methods from rapeseed cake on cancer cell lines.

    PubMed

    Cobs-Rosas, M; Concha-Olmos, J; Weinstein-Oppenheimer, C; Zúñiga-Hansen, M E

    2015-03-01

    In this work the antiproliferative activity of pectic substances obtained by different extraction methods from defatted rapeseed cake was assessed on cancer cell lines. The process consisted of sequential treatment with alkalized water (pH∼8), EDTA (0.01 M), alkaline protease (Alkalase 2.4L) and a commercial pectinase preparation (Viscozyme L or Pectinex Ultra SP-L). Pectic extracts identification was performed using spectroscopy and chromatography techniques. FT-IR and HPLC-IR results suggest that the neutral pectic extracts produced would be arabinogalactans and β-galactans. All the pectic substances extracted (acid and neutral) from RSC exhibited antiproliferative activity, being more effective on MCF-7 cells than Caco-2. The most effective pectic extract was obtained by Alkalase 2.4 L which killed over 80% of MCF-7 cells and 60% of Caco-2 cells. At less than 10 mg/mL pectic extracts enriched in neutral sugars also exhibited antiproliferative activity (50 and 40%, respectively), which was superior to the modified citric pectins activity at the same concentration for the breast cancer cell line (61.6% for MCF-7 and 49.9% for Caco-2 cells). These results show that the antiproliferative activity depends on both the type of pectin (acid or neutral) and the extraction procedure.

  14. Effects of Storage Time on Total Protein and Globulin Concentrations in Bovine Fresh Frozen Plasma Obtained for Transfusion

    PubMed Central

    Proverbio, D.; Spada, E.; Baggiani, L.; Bagnagatti De Giorgi, G.; Roggero, N.; Belloli, A.; Pravettoni, D.; Perego, R.

    2015-01-01

    To evaluate the effects of storage conditions on total protein (TP) and globulin fractions in fresh frozen bovine plasma units prepared and stored for transfusion, TP and globulin fractions were evaluated in fresh plasma and at 1 month and 6 and 12 months after blood collection in plasma stored at −20°C. Significant differences in concentrations were found in the median concentration of total protein (P = 0.0336), between 0 months and 1 month (P = 0.0108), 0 and 6 months (P = 0.0023), and 0 and 12 months (P = 0.0027), in mean concentration (g/dL) of albumin (P = 0.0394), between 0 months and 1 month (P = 0.0131), 0 and 6 months (P = 0.0035), and 0 and 12 months (P = 0.0038), and beta-2 fraction (P = 0.0401), between 0 and 6 months (P = 0.0401) and 0 and 12 months (P = 0.0230). This study suggests that total gamma globulin concentration in bovine frozen plasma is stable for 12 months at −20°C. Total protein, ALB, and beta-2 fraction have significantly different concentrations (g/dL) when compared to prestorage. This study has shown IgG protein fraction stability in bovine fresh frozen plasma collected for transfusion; therefore, bovine fresh frozen plasma seems to be suitable for the treatment of hypogammaglobulinemia (failure of passive transfer) in calves when stored for 12 months at −20°C. PMID:25767825

  15. Antioxidant and anti-inflammatory activity of extract obtained from Aspergillus candidus MTCC 2202 broth filtrate.

    PubMed

    Malpure, Pankaj P; Shah, Abhishek S; Juvekar, Archana R

    2006-06-01

    Antioxidant potential of Aspergillus candidus MTCC 2202 broth filtrate extract was studied using different antioxidant models, whereas anti-inflammatory potential was studied using carrageenan-induced rat paw oedema model. The ethyl acetate extract at 1000 microg/ml showed maximum scavenging activity of the stable radical 1,1-diphenyl,2-picryl hydrazyl upto 96.65% (IC50=430.36 microg/ml) and scavenging of the radical cation, 2,2-azinobis-(3-ethylbenzothiazoline-6-sulphonate) upto 92.25% (IC50=606.29 microg/ml) at the same concentration. The extract had good reducing power, however showed moderate inhibition for conjugated dienes and thiobarbituric acid reactive acid substances (59.56 and 51.45%). The total phenolic content of various extracts of A. candidus broth filtrate was measured and a correlation between radical scavenging activities of extracts with total phenolic content was observed. The ethyl acetate extract (125 mg/kg ip) showed significant anti-inflammatory activity in carrageenan-induced rat paw oedema model. The exhibited antioxidant activity of ethyl acetate extract of A. candidus broth filtrate was comparable with BHA and ascorbic acid, while anti-inflammatory activity was comparable with standard diclofenac sodium.

  16. Thermal Characterization of PZT Ceramics Obtained by Mechanically Activated Mixed Oxides Using Different Pb Sources

    NASA Astrophysics Data System (ADS)

    Rivera-Ruedas, G.; Ramírez-López, L. M.; Sánchez de Jesús, F.; Bolarín-Miró, A.; Muñoz-Saldaña, J.; Yáñez-Limón, J. M.

    2012-12-01

    In this study, three sets of PZT samples with compositions 57/43 and 55/45 (rhombohedral phase), 53/47 and 51/49 (tetragonal phase) prepared by mechanochemical activation of powder mixtures (during 4 h of milling) and thermal treatment (sintered at 1200 °C for 4 h) were thermally characterized. The three sets of compositions were prepared using different Pb sources (A-PbO, B-PbO2, and C-Pb3O4). The thermal characterization of sintered samples was carried out by photoacoustic spectroscopy and differential scanning calorimetry, to obtain the thermal diffusivity and specific heat ( c p ). The DSC thermograms also allowed the determination of the Curie temperature, and the thermal conductivity was calculated combining the results of the thermal diffusivity, specific heat, and density. The samples obtained with Pb3O4 showed a theoretical density higher than 95 %, whereas those obtained from PbO2 precursors showed a lower densification rate (around 89 %). The samples obtained with Pb3O4 with compositions 53/47 and 51/49 also showed the highest values of thermal diffusivity (7.3 ± 0.4) × 10-7m2· s-1 and (6.6 ± 0.3) × 10-7m2· s-1, respectively.

  17. Concentration of biologically active compounds extracted from Ilex paraguariensis St. Hil. by nanofiltration.

    PubMed

    Murakami, Aureanna Nairne Negrão; Amboni, Renata Dias de Mello Castanho; Prudêncio, Elane Schwinden; Amante, Edna Regina; Fritzen-Freire, Carlise Beddin; Boaventura, Brunna Cristina Bremer; Muñoz, Isabella de Bona; Branco, Catia Dos Santos; Salvador, Miriam; Maraschin, Marcelo

    2013-11-01

    The aim of this study was to characterise the bioactive compounds in mate (Ilex paraguariensis St. Hil) extract and in concentrated mate extract obtained by nanofiltration (NF). Also, the impact of NF on the antioxidant activity of both mate extracts was evaluated in vitro and using eukaryotic cells of Saccharomyces cerevisiae (yeast assay). The results showed a significant increase in the contents of total phenolics (338%), chlorogenic acid (483%), theobromine (323%), caffeine (251%), chlorophyll (321%), condensed tannins (278%) and saponins (211%) in the concentrated mate extract. The concentrated mate extract showed higher in vitro antioxidant activity than the mate extract. According to the results obtained, it can be stated that the use of nanofiltration membrane is a valid approach for the concentration of biologically active compounds in aqueous extract of mate.

  18. Effect of Boric Acid Concentration on Viscosity of Slag and Property of Weld Metal Obtained from Underwater Wet Welding

    NASA Astrophysics Data System (ADS)

    Guo, Ning; Guo, Wei; Xu, Changsheng; Du, Yongpeng; Feng, Jicai

    2015-06-01

    Underwater wet welding is a crucial repair and maintenance technology for nuclear plant. A boric acid environment raises a new challenge for the underwater welding maintenance of nuclear plant. This paper places emphasis on studying the influence of a boric acid environment in nuclear plant on the underwater welding process. Several groups of underwater wet welding experiments have been conducted in boric acid aqueous solution with different concentration (0-35000 ppm). The viscosity of the welding slag and the mechanical properties of welds, such as the hardness, strength, and elongation, have been studied. The results show that with increasing boric acid concentration, the viscosity of the slag decreases first and then increases at a lower temperature (less than 1441 °C). However, when the temperature is above 1480 °C, the differences between the viscosity measurements become less pronounced, and the viscosity tends to a constant value. The hardness and ductility of the joints can be enhanced significantly, and the maximum strength of the weld metal can be reached at 2300 ppm.

  19. Antioxidant activity of fractions from oregano essential oils obtained by molecular distillation.

    PubMed

    Olmedo, Ruben; Nepote, Valeria; Grosso, Nelson Ruben

    2014-08-01

    The objective of this study was to determine the antioxidant activity of fractions separated from oregano essential oil by short-path molecular distillation. Two residue (R1 and R2) and two distillate (D1 and D2) fractions were prepared by molecular distillation. The major components were: carvacrol, terpinen-4-ol and γ-terpinene in R1 and R2; and γ-terpinene, α-terpineol and sabinene in D1 and D2. Free-radical scavenging activity was observed in all fractions and was highest in R2 (77.2%). D1 and D2 showed a smaller amount of volatile oxidation compounds produced from sunflower oil stored at 60°C for 14days. The greatest antioxidant activity was observed in D1 and D2. The thermal stability of oregano essential oil and its fractions was also analysed. R1 and R2 presented an increased carvacrol concentration and thermal stability. The short-path molecular distillation fractions can be used to prepare fractions from oregano essential oil with a higher antioxidant activity.

  20. Antioxidant activity of fractions from oregano essential oils obtained by molecular distillation.

    PubMed

    Olmedo, Ruben; Nepote, Valeria; Grosso, Nelson Ruben

    2014-08-01

    The objective of this study was to determine the antioxidant activity of fractions separated from oregano essential oil by short-path molecular distillation. Two residue (R1 and R2) and two distillate (D1 and D2) fractions were prepared by molecular distillation. The major components were: carvacrol, terpinen-4-ol and γ-terpinene in R1 and R2; and γ-terpinene, α-terpineol and sabinene in D1 and D2. Free-radical scavenging activity was observed in all fractions and was highest in R2 (77.2%). D1 and D2 showed a smaller amount of volatile oxidation compounds produced from sunflower oil stored at 60°C for 14days. The greatest antioxidant activity was observed in D1 and D2. The thermal stability of oregano essential oil and its fractions was also analysed. R1 and R2 presented an increased carvacrol concentration and thermal stability. The short-path molecular distillation fractions can be used to prepare fractions from oregano essential oil with a higher antioxidant activity. PMID:24629960

  1. Using Spitzer Data To Obtain Dust Distribution Arounfd The Active Galactic Nucleus NGC 4051

    NASA Astrophysics Data System (ADS)

    Pereira, Vincent; Burrell, A.; Chavez, O.; Fawcett, E.; Elias, R.; Lugo, T.; Morillo, E.; Purpura, M.; Sorokin, S.; Gorjian, V.; Adkins, J.; Borders, K.; Kelly, S.; Martin, C.; Mendez, B.; Paradis, J.; Pittman, P.; Sepulveda, B.

    2010-01-01

    We have used the Rees'model of Seyfert I galaxies to make detailed calculations of dust distribution as a function of the slope of the spectral intensity versus frequency curve in the infra-red. From these results and our observations of the active galactic nucleus NGC 4051 with the Spitzer Space Telescope Infrared Array Camera (IRAC) we obtain the dust distribution function for this nucleus. We feel that this research project with its underlying physical concepts serves as a good introduction to the physics of Seyfert galaxies for high school students.

  2. Antiandrogenic activity of phthalate mixtures: Validity of concentration addition

    SciTech Connect

    Christen, Verena; Crettaz, Pierre; Oberli-Schrämmli, Aurelia; Fent, Karl

    2012-03-01

    Phthalates and bisphenol A have very widespread use leading to significant exposure of humans. They are suspected to interfere with the endocrine system, including the androgen, estrogen and the thyroid hormone system. Here we analyzed the antiandrogenic activity of six binary, and one ternary mixture of phthalates exhibiting complete antiandrogenic dose–response curves, and binary mixtures of phthalates and bisphenol A at equi-effective concentrations of EC{sub 10}, EC{sub 25} and EC{sub 50} in MDA-kb2 cells. Mixture activity followed the concentration addition (CA) model with a tendency to synergism at high and antagonism at low concentrations. Isoboles and the toxic unit approach (TUA) confirmed the additive to synergistic activity of the binary mixtures BBP + DBP, DBP + DEP and DEP + BPA at high concentrations. Both methods indicate a tendency to antagonism for the EC{sub 10} mixtures BBP + DBP, BBP + DEP and DBP + DEP, and the EC{sub 25} mixture of DBP + BPA. A ternary mixture revealed synergism at the EC{sub 50}, and weak antagonistic activity at the EC{sub 25} level by the TUA. A mixture of five phthalates representing a human urine composition and reflecting exposure to corresponding parent compounds showed no antiandrogenic activity. Our study demonstrates that CA is an appropriate concept to account for mixture effects of antiandrogenic phthalates and bisphenol A. The interaction indicates a departure from additivity to antagonism at low concentrations, probably due to interaction with the androgen receptor and/or cofactors. This study emphasizes that a risk assessment of phthalates should account for mixture effects by applying the CA concept. -- Highlights: ► Antiandrogenic activity of mixtures of 2 and 3 phthalates are assessed in MDA-kb2 cells. ► Mixture activities followed the concentration addition model. ► A tendency to synergism at high and antagonism at low levels occurred.

  3. Concentration-dependent activity of antibiotics in natural environments

    PubMed Central

    Bernier, Steve P.; Surette, Michael G.

    2013-01-01

    Bacterial responses to antibiotics are concentration-dependent. At high concentrations, antibiotics exhibit antimicrobial activities on susceptible cells, while subinhibitory concentrations induce diverse biological responses in bacteria. At non-lethal concentrations, bacteria may sense antibiotics as extracellular chemicals to trigger different cellular responses, which may include an altered antibiotic resistance/tolerance profile. In natural settings, microbes are typically in polymicrobial communities and antibiotic-mediated interactions between species may play a significant role in bacterial community structure and function. However, these aspects have not yet fully been explored at the community level. Here we discuss the different types of interactions mediated by antibiotics and non-antibiotic metabolites as a function of their concentrations and speculate on how these may amplify the overall antibiotic resistance/tolerance and the spread of antibiotic resistance determinants in a context of polymicrobial community. PMID:23422936

  4. Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet.

    PubMed

    Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

    2016-01-01

    To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring. PMID:26094571

  5. Natural and anthropogenic radionuclide activity concentrations in the New Zealand diet.

    PubMed

    Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

    2016-01-01

    To support New Zealand's food safety monitoring regime, a survey was undertaken to establish radionuclide activity concentrations across the New Zealand diet. This survey was undertaken to better understand the radioactivity content of the modern diet and also to assess the suitability of the current use of milk as a sentinel for dietary radionuclide trends. Thirteen radionuclides were analysed in 40 common food commodities, including animal products, fruits, vegetables, cereal grains and seafood. Activity was detected for (137)Caesium, (90)Strontium and (131)Iodine. No other anthropogenic radionuclides were detected. Activity concentrations of the three natural radionuclides of Uranium and the daughter radionuclide (210)Polonium were detected in the majority of food sampled, with a large variation in magnitude. The maximum activity concentrations were detected in shellfish for all these radionuclides. Based on the established activity concentrations and ranges, the New Zealand diet contains activity concentrations of anthropogenic radionuclides far below the Codex Alimentarius guideline levels. Activity concentrations obtained for milk support its continued use as a sentinel for monitoring fallout radionuclides in terrestrial agriculture. The significant levels of natural and anthropogenic radionuclide activity concentrations detected in finfish and molluscs support undertaking further research to identify a suitable sentinel for New Zealand seafood monitoring.

  6. ACE-I Inhibitory Activity from Phaseolus lunatus and Phaseolus vulgaris Peptide Fractions Obtained by Ultrafiltration.

    PubMed

    Betancur-Ancona, David; Dávila-Ortiz, Gloria; Chel-Guerrero, Luis Antonio; Torruco-Uco, Juan Gabriel

    2015-11-01

    The involvement of angiotensin-I-converting enzyme (ACE-I) as one of the mechanisms controlling blood pressure is being studied to find alternative means of control of hypertension on human beings. On the market there are synthetic drugs that can control it, but these can cause undesirable health side effects. In this work was assessed the fractionation by ultrafiltration of the Lima bean (Phaseolus lunatus) and Jamapa bean (Phaseolus vulgaris), protein hydrolysates obtained with Alcalase(®) and Flavourzyme(®) on ACE-I inhibitory activity. Four membranes of different molecular cutoffs (10, 5, 3, and 1 kDa) were used. Fractions that had a higher inhibitory activity in both legumes were denominated as E (<1 kDa) with IC50 of 30.3 and 51.8 μg/mL values for the P. lunatus with Alcalase and Flavourzyme, respectively, and for the Phaseolus vulgaris with Alcalase and Flavourzyme with about 63.8 and 65.8 μg/mL values, respectively. The amino acid composition of these fractions showed residues in essential amino acids, which make a good source of energy and amino acids. On the other hand, the presence of hydrophobic amino acids such as V and P is a determining factor in the ACE-I inhibitor effect. The results suggest the possibility of obtaining and utilizing these peptide fractions in the development and innovation of a functional product that helps with treatment and/or prevention of hypertension.

  7. Athletic Activity and Hormone Concentrations in High School Female Athletes

    PubMed Central

    Wojtys, Edward M.; Jannausch, Mary L.; Kreinbrink, Jennifer L.; Harlow, Siobán D.; Sowers, MaryFran R.

    2015-01-01

    Context: Physical activity may affect the concentrations of circulating endogenous hormones in female athletes. Understanding the relationship between athletic and physical activity and circulating female hormone concentrations is critical. Objective: To test the hypotheses that (1) the estradiol-progesterone profile of high school adolescent girls participating in training, conditioning, and competition would differ from that of physically inactive, age-matched adolescent girls throughout a 3-month period; and (2) athletic training and conditioning would alter body composition (muscle, bone), leading to an increasingly greater lean–body-mass to fat–body-mass ratio with accompanying hormonal changes. Design: Cohort study. Settings: Laboratory and participants' homes. Patients or Other Participants: A total of 106 adolescent girls, ages 14–18 years, who had experienced at least 3 menstrual cycles in their lifetime. Main Outcome Measure(s): Participants were prospectively monitored throughout a 13-week period, with weekly physical activity assessments and 15 urine samples for estrogen, luteinizing hormone, creatinine, and progesterone concentrations. Each girl underwent body-composition measurements before and after the study period. Results: Seventy-four of the 98 girls (76%) who completed the study classified themselves as athletes. Body mass index, body mass, and fat measures remained stable, and 17 teenagers had no complete menstrual cycle during the observation period. Mean concentrations of log(estrogen/creatinine) were slightly greater in nonathletes who had cycles of <24 or >35 days. Mean log(progesterone/creatinine) concentrations in nonathletes were less in the first half and greater in the second half of the cycle, but the differences were not statistically significant. Conclusions: A moderate level of athletic or physical activity did not influence urine concentrations of estrogen, progesterone, or luteinizing hormones. However, none of the

  8. Activity concentration of caesium-137 in agricultural soils.

    PubMed

    Aslani, Mahmoud A A; Aytas, Sule; Akyil, Sema; Yaprak, Gunseli; Yener, Gungor; Eral, Meral

    2003-01-01

    In this study, we measured 137Cs activity concentrations in the soil samples taken from agricultural lands in the Buyuk Menderes Basin in Turkey in 1997 and 1998. The soil samples were collected from 42 sites in this Basin. The activity concentration of 137Cs was found to range between 2.81+/-0.17 Bq.kg(-1) and 20.75+/-0.29 Bq.kg(-1). The effect of organic matter, clay, silt and sand contents and pH of the soil on the relative adsorption of the 137Cs on the soil surface were also studied.

  9. Phytochemical, antimicrobial, and antioxidant activities of different citrus juice concentrates.

    PubMed

    Oikeh, Ehigbai I; Omoregie, Ehimwenma S; Oviasogie, Faith E; Oriakhi, Kelly

    2016-01-01

    The search for new antimicrobial compounds is ongoing. Its importance cannot be overemphasized in an era of emerging resistant pathogenic organisms. This study therefore investigated the phytochemical composition and antioxidant and antimicrobial activities of different citrus juice concentrates. Fruit juices of Citrus tangerine (tangerine), Citrus paradisi (grape), Citrus limon (lemon), and Citrus aurantifolia (lime) were evaluated. Antimicrobial activities against five bacterial and three fungal strains were evaluated. The results revealed the presence of alkaloids, flavonoids, steroids, terpenoids, saponins, cardiac glycosides, and reducing sugars in all the juice concentrates. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging capacities varied with tangerine and grape juices having better scavenging capacities than lemon and lime juices. Grape juice was observed to have a significantly higher (P < 0.05) ferric-reducing antioxidant potential (FRAP) value (364.2 ± 10.25 μmol/L Fe(II)/g of the extract) than the reference antioxidant, ascorbic acid (312.88 ± 5.61 μmol/L). Antimicrobial studies revealed differential antimicrobial activities against different microbial strains. Zones of inhibition ranging from 4 to 26 mm were observed for the antibacterial tests with 0-24 mm for antifungal test. Minimum inhibitory concentrations (MIC) and minimum bacteriostatic concentrations (MBC) for concentrates against bacterial strains ranged from 12.5 to 200 μg/mL. Lemon and lime juice concentrates had lower MIC and MBC values with orange and tangerine having the highest values. Minimum fungicidal concentrations ranged from 50 to 200 μg/mL. The results of this study suggest that these juice concentrates may have beneficial antimicrobial roles that can be exploited in controlling unwanted microbial growth.

  10. Antioxidant activity, cytotoxic activity and metabolic profiling of juices obtained from saffron (Crocus sativus L.) floral by-products.

    PubMed

    Tuberoso, Carlo I G; Rosa, Antonella; Montoro, Paola; Fenu, Maurizio Antonio; Pizza, Cosimo

    2016-05-15

    Juices obtained from cold-pressed saffron (Crocus sativus L.) floral by-products were evaluated as a potential source of compounds with antioxidant and cytotoxic activities. Floral by-products were split in two batches for extraction 24 and 48h after flower harvesting, respectively. The in vitro anti-oxidant activity of these extracts was tested using the FRAP and DPPH assays, and two biological models of lipid oxidation (activity in preventing cholesterol degradation and protection against Cu(2+)-mediated degradation of the liposomal unsaturated fatty acids). The cytotoxic activity was evaluated using the MTT assay. The results show that extracts obtained 48h post-harvest contained higher levels of total polar phenols and had the highest antioxidant activity in all of the performed assays. The LC-DAD and LC-ESI-(HR)MS(n) metabolic profiles showed high levels of kaempferol derivatives and anthocyanins. This study suggests that juices from saffron floral by-products could potentially be used to develop new products for the food and health industry. PMID:26775939

  11. Antioxidant activity, cytotoxic activity and metabolic profiling of juices obtained from saffron (Crocus sativus L.) floral by-products.

    PubMed

    Tuberoso, Carlo I G; Rosa, Antonella; Montoro, Paola; Fenu, Maurizio Antonio; Pizza, Cosimo

    2016-05-15

    Juices obtained from cold-pressed saffron (Crocus sativus L.) floral by-products were evaluated as a potential source of compounds with antioxidant and cytotoxic activities. Floral by-products were split in two batches for extraction 24 and 48h after flower harvesting, respectively. The in vitro anti-oxidant activity of these extracts was tested using the FRAP and DPPH assays, and two biological models of lipid oxidation (activity in preventing cholesterol degradation and protection against Cu(2+)-mediated degradation of the liposomal unsaturated fatty acids). The cytotoxic activity was evaluated using the MTT assay. The results show that extracts obtained 48h post-harvest contained higher levels of total polar phenols and had the highest antioxidant activity in all of the performed assays. The LC-DAD and LC-ESI-(HR)MS(n) metabolic profiles showed high levels of kaempferol derivatives and anthocyanins. This study suggests that juices from saffron floral by-products could potentially be used to develop new products for the food and health industry.

  12. Fetal Functional Brain Age Assessed from Universal Developmental Indices Obtained from Neuro-Vegetative Activity Patterns

    PubMed Central

    Hoyer, Dirk; Tetschke, Florian; Jaekel, Susan; Nowack, Samuel; Witte, Otto W.; Schleußner, Ekkehard; Schneider, Uwe

    2013-01-01

    Fetal brain development involves the development of the neuro-vegetative (autonomic) control that is mediated by the autonomic nervous system (ANS). Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS) based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4–40.3 weeks of gestation) preclassified in quiet sleep (n = 113, 63 females) and active sleep (n = 286, 145 females) state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5). The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R2 of training and validation set) of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications). We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA dependent f

  13. Natural activity concentrations in bottled drinking water and consequent doses.

    PubMed

    Kabadayi, Önder; Gümüs, Hasan

    2012-07-01

    The radioactivity concentrations of nuclides (238)U, (232)Th and (40)K in bottled drinking water from six different manufacturers from Turkey were measured using high-resolution gamma-ray spectrometry. The measurement was done using a coaxial high-purity germanium detector system coupled to Ortec-Dspect jr digital MCA system. The average measured activity concentrations of the nuclides (238)U, (232)Th and (40)K are found to be 0.781, 1.05 and 2.19 Bq l(-1), respectively. The measured activity concentrations have been compared with similar studies from different locations. The annual effective doses for ingestion of radionuclides in the water are found to be 0.0246 mSv for (238)U and 0.169 mSv for (232)Th.

  14. Natural Radionuclide Activity Concentrations In Spas Of Argentina

    SciTech Connect

    Gnoni, G.; Czerniczyniec, M.; Canoba, A.; Palacios, M.

    2008-08-07

    Geothermal waters have been used on a large scale for bathing, drinking and medical purposes. These waters can contain natural radionuclides that may increase the exposure to people. In this work the most important natural radionuclide activity concentrations in different thermal spas of Argentina were measured to characterize waters and to evaluate the exposure of workers and members of the public.

  15. Natural Radionuclide Activity Concentrations In Spas Of Argentina

    NASA Astrophysics Data System (ADS)

    Gnoni, G.; Czerniczyniec, M.; Canoba, A.; Palacios, M.

    2008-08-01

    Geothermal waters have been used on a large scale for bathing, drinking and medical purposes. These waters can contain natural radionuclides that may increase the exposure to people. In this work the most important natural radionuclide activity concentrations in different thermal spas of Argentina were measured to characterize waters and to evaluate the exposure of workers and members of the public.

  16. Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding.

    PubMed

    Ortega-Toro, Rodrigo; Morey, Iris; Talens, Pau; Chiralt, Amparo

    2015-08-20

    Bilayer films consisting of one layer of PCL with either one of thermoplastic starch (S) or one of thermoplastic starch with 5% PCL (S95) were obtained by compression molding. Before compression, aqueous solutions of ascorbic acid or potassium sorbate were sprayed onto the S or S95 layers in order to plasticize them and favor layer adhesion. S95 films formed bilayers with PCL with very good adhesion and good mechanical performance, especially when potassium sorbate was added at the interface. All bilayers enhanced their barrier properties to water vapour (up to 96% compared to net starch films) and oxygen (up to 99% compared to PCL pure). Bilayers consisting of PCL and starch containing 5% PCL, with potassium sorbate at the interface, showed the best mechanical and barrier properties and interfacial adhesion while having active properties, associated with the antimicrobial action of potassium sorbate. PMID:25965485

  17. Active bilayer films of thermoplastic starch and polycaprolactone obtained by compression molding.

    PubMed

    Ortega-Toro, Rodrigo; Morey, Iris; Talens, Pau; Chiralt, Amparo

    2015-08-20

    Bilayer films consisting of one layer of PCL with either one of thermoplastic starch (S) or one of thermoplastic starch with 5% PCL (S95) were obtained by compression molding. Before compression, aqueous solutions of ascorbic acid or potassium sorbate were sprayed onto the S or S95 layers in order to plasticize them and favor layer adhesion. S95 films formed bilayers with PCL with very good adhesion and good mechanical performance, especially when potassium sorbate was added at the interface. All bilayers enhanced their barrier properties to water vapour (up to 96% compared to net starch films) and oxygen (up to 99% compared to PCL pure). Bilayers consisting of PCL and starch containing 5% PCL, with potassium sorbate at the interface, showed the best mechanical and barrier properties and interfacial adhesion while having active properties, associated with the antimicrobial action of potassium sorbate.

  18. Variability in Obtaining Institutional Review Board Approval for Quality Improvement Activities in Residency Programs

    PubMed Central

    Conforti, Lisa N.; Hess, Brian J.; Ross, Kathryn M.; Lynn, Lorna A.; Holmboe, Eric S.

    2012-01-01

    Introduction Quality improvement (QI) activities are an important part of residency training. National studies are needed to inform best practices in QI training and experience for residents. The impact of the Institutional Review Board (IRB) process on such studies is not well described. Methods This observational study looked at time, length, comfort level, and overall quality of experience for 42 residency training programs in obtaining approval or exemption for a nationally based educational QI study. Results For the 42 programs in the study, the time period to IRB approval/exemption was highly variable, ranging from less than 1 week to 56.5 weeks; mean and median time was approximately 18 weeks (SD, 10.8). Greater reported comfort with the IRB process was associated with less time to obtain approval (r  =  −.50; P < .01; 95% CI, −0.70 to −0.23). A more positive overall quality of experience with the IRB process was also associated with less time to obtain IRB approval (r  =  −.60; P < .01; 95% CI, −0.74 to −0.36). Discussion The IRB process for residency programs initiating QI studies shows considerable variance that is not explained by attributes of the projects. New strategies are needed to assist and expedite IRB processes for QI research in educational settings and reduce interinstitutional variability and increase comfort level among educators with the IRB process. PMID:23451318

  19. Antiandrogenic activity of phthalate mixtures: validity of concentration addition.

    PubMed

    Christen, Verena; Crettaz, Pierre; Oberli-Schrämmli, Aurelia; Fent, Karl

    2012-03-01

    Phthalates and bisphenol A have very widespread use leading to significant exposure of humans. They are suspected to interfere with the endocrine system, including the androgen, estrogen and the thyroid hormone system. Here we analyzed the antiandrogenic activity of six binary, and one ternary mixture of phthalates exhibiting complete antiandrogenic dose-response curves, and binary mixtures of phthalates and bisphenol A at equi-effective concentrations of EC(10), EC(25) and EC(50) in MDA-kb2 cells. Mixture activity followed the concentration addition (CA) model with a tendency to synergism at high and antagonism at low concentrations. Isoboles and the toxic unit approach (TUA) confirmed the additive to synergistic activity of the binary mixtures BBP+DBP, DBP+DEP and DEP+BPA at high concentrations. Both methods indicate a tendency to antagonism for the EC(10) mixtures BBP+DBP, BBP+DEP and DBP+DEP, and the EC(25) mixture of DBP+BPA. A ternary mixture revealed synergism at the EC(50), and weak antagonistic activity at the EC(25) level by the TUA. A mixture of five phthalates representing a human urine composition and reflecting exposure to corresponding parent compounds showed no antiandrogenic activity. Our study demonstrates that CA is an appropriate concept to account for mixture effects of antiandrogenic phthalates and bisphenol A. The interaction indicates a departure from additivity to antagonism at low concentrations, probably due to interaction with the androgen receptor and/or cofactors. This study emphasizes that a risk assessment of phthalates should account for mixture effects by applying the CA concept.

  20. The active titration method for measuring local hydroxyl radical concentration

    NASA Technical Reports Server (NTRS)

    Sprengnether, Michele; Prinn, Ronald G.

    1994-01-01

    We are developing a method for measuring ambient OH by monitoring its rate of reaction with a chemical species. Our technique involves the local, instantaneous release of a mixture of saturated cyclic hydrocarbons (titrants) and perfluorocarbons (dispersants). These species must not normally be present in ambient air above the part per trillion concentration. We then track the mixture downwind using a real-time portable ECD tracer instrument. We collect air samples in canisters every few minutes for roughly one hour. We then return to the laboratory and analyze our air samples to determine the ratios of the titrant to dispersant concentrations. The trends in these ratios give us the ambient OH concentration from the relation: dlnR/dt = -k(OH). A successful measurement of OH requires that the trends in these ratios be measureable. We must not perturb ambient OH concentrations. The titrant to dispersant ratio must be spatially invariant. Finally, heterogeneous reactions of our titrant and dispersant species must be negligible relative to the titrant reaction with OH. We have conducted laboratory studies of our ability to measure the titrant to dispersant ratios as a function of concentration down to the few part per trillion concentration. We have subsequently used these results in a gaussian puff model to estimate our expected uncertainty in a field measurement of OH. Our results indicate that under a range of atmospheric conditions we expect to be able to measure OH with a sensitivity of 3x10(exp 5) cm(exp -3). In our most optimistic scenarios, we obtain a sensitivity of 1x10(exp 5) cm(exp -3). These sensitivity values reflect our anticipated ability to measure the ratio trends. However, because we are also using a rate constant to obtain our (OH) from this ratio trend, our accuracy cannot be better than that of the rate constant, which we expect to be about 20 percent.

  1. Modeling the (212)Pb activity concentration in the lower atmosphere.

    PubMed

    Werzi, R

    2010-02-01

    A worldwide radionuclide network of 80 stations, part of the International Monitoring System, is being setup to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The radioactivity sampled at these stations is primarily (220)Rn progenies affecting the detection capability. A model linking the (220)Rn emanation with the sampled (212)Pb activity was developed and is presented here. The model and the performed measurements show that the variation of the sampled (212)Pb activity can be fully explained by the variation of the local (220)Rn activity concentration. PMID:19875214

  2. Some methods of obtaining quantitative structure-activity relationships for quantities of environmental interest

    SciTech Connect

    Charton, M.

    1985-09-01

    Methods are described for obtaining quantitative structure-activity relationships (QSAR) for the estimation of quantities of environmental interest. Toxicities of alkylamines and of alkyl alkanoates are well correlated by the alkyl bioactivity branching equation (ABB). Narcotic activities of 1,1-disubstituted ethylenes are correlated by the intermolecular forces bioactivity (IMF) equation. When the data set has a limited number of substituents in equivalent positions the group number (GN) equation, derivable from the IMF equation, can be used for correlation. It has been successfully applied to aqueous solubilities, 1-octanol-water partition coefficients, and bioaccumulation factors and ecological magnifications for organochlorine compounds. A combination of the omega method for combining data sets for different organisms with the GN equation has been used to correlate toxicities of organochlorine insecticides in two species of fish. Toxicities of carbamates have been correlated by a combination of the zeta method and the IMFB equation. The ABB and the GN equations are particularly useful in that they generally do not require parameter tables, and that the parameters they use are error-free. The methods presented here, as shown by the examples given, should make it possible to establish a collection of QSAR for toxicities, bioaccumulation factors, aqueous solubilities, partition coefficients, and other properties of sets of compounds of environmental interest. 29 references.

  3. Pharmacological mechanisms underlying gastroprotective activities of the fractions obtained from Polygonum minus in Sprague Dawley rats.

    PubMed

    Qader, Suhailah Wasman; Abdulla, Mahmood Ameen; Chua, Lee Suan; Sirat, Hasnah Mohd; Hamdan, Salehhuddin

    2012-01-01

    The leaves of Polygonum minus were fractionated using an eluting solvent to evaluate the pharmacological mechanisms underlying the anti-ulcerogenic activity of P. minus. Different P. minus fractions were obtained and evaluated for their ulcer preventing capabilities using the ethanol induction method. In this study, Sprague Dawley rats weighing 150-200 g were used. Different parameters were estimated to identify the active fraction underlying the mechanism of the gastroprotective action of P. minus: the gastric mucus barrier, as well as superoxide dismutase, total hexosamine, and prostaglandin synthesis. Amongst the five fractions from the ethanolic extract of P. minus, the ethyl acetate:methanol 1:1 v/v fraction (F2) significantly (p < 0.005) exhibited better inhibition of ulcer lesions in a dose-dependent manner. In addition, rats pre-treated with F2 showed a significant elevation in superoxide dismutase (SOD), hexosamine and PGE2 levels in the stomach wall mucosa in a dose-dependent matter. Based on these results, the ethyl acetate:methanol 1:1 v/v fraction was considered to be the best fraction for mucous protection in the ethanol induction model. The mechanisms underlying this protection were attributed to the synthesis of antioxidants and PGE2. PMID:22408403

  4. Improved detectability in medical microwave radio-thermometers as obtained by active antennas.

    PubMed

    Jacobsen, Svein; Klemetsen, Øystein

    2008-12-01

    Microwave radiometry is a spectral measurement technique for resolving blackbody radiation of heated matter above absolute zero. The emission levels vary with frequency and are at body temperatures maximized in the infrared spectral band. Medical radio-thermometers are mostly noninvasive short-range instruments that can provide temperature distributions in subcutaneous biological tissues when operated in the microwave region. However, a crucial limitation of the microwave radiometric observation principle is the extremely weak signal level of the thermal noise emitted by the lossy material (-174 dBm/Hz at normal body temperature). To improve the radiometer SNR, we propose to integrate a tiny, moderate gain, low-noise preamplifier (LNA) close to the antenna terminals as to obtain increased detectability of deep seated thermal gradients within the volume under investigation. The concept is verified experimentally in a lossy phantom medium by scanning an active antenna across a thermostatically controlled water phantom with a hot object embedded at 38 mm depth. Three different setups were investigated with decreasing temperature contrasts between the target and ambient medium. As a direct consequence of less ripple on the raw radiometric signal, statistical analysis shows a marked increase in signal-to-clutter ratio of the brightness temperature spatial scan profiles, when comparing active antenna operation with conventional passive setups.

  5. Sulfation modification and anticoagulant activity of the polysaccharides obtained from persimmon (Diospyros kaki L.) fruits.

    PubMed

    Lu, Xiaoyun; Mo, Xiaoyan; Guo, Hui; Zhang, Yali

    2012-12-01

    The optimal conditions for sulfation of polysaccharides from persimmon fruits (PFP) with chlorosulfonic acid-pyridine (CSA-Pyr) method were determined by response surface methodology. Box-Behnken design was applied to evaluate the effects of three independent variables (volume ratio of Pyr to CSA, volume ratio of PFP to SO(3)Pyr and reaction time) on the degree of substitution (DS), molecular weight (MW) and activated partial thromboplastin time (APTT) of sulfated polysaccharides (PFP-S). The APTT activity of PFP-S could be improved by application of various volume ratio of Pyr to CSA, volume ratio of PFP to SO(3)Pyr and reaction time, which was possible due to the degradation of polysaccharides to different extent and increasing of DS. The optimal conditions to obtain the strongest APTT of PFP-S were the volume ratio of CSA to Pyr of 1:8, the volume ratio of SO(3)Pyr to PFP of 1:3.6 and the reaction time of 3 h, respectively.

  6. Anti-Trichomonas vaginalis activity of Hypericum polyanthemum extract obtained by supercritical fluid extraction and isolated compounds.

    PubMed

    Cargnin, Simone Tasca; Vieira, Patrícia de Brum; Cibulski, Samuel; Cassel, Eduardo; Vargas, Rubem Mário Figueiró; Montanha, Jarbas; Roehe, Paulo; Tasca, Tiana; von Poser, Gilsane Lino

    2013-04-01

    The anti-Trichomonas vaginalis activity of Hypericum polyanthemum extract obtained by supercritical fluid extraction (50°C, 150bar) and the chemical compounds isolated and purified from this extract (benzopyrans HP1, HP2, HP3, and phloroglucinol derivative uliginosin B) were assessed. All samples had anti-T. vaginalis activity; however, HP1 demonstrated the best selectivity against this protozoan (metronidazole-resistant and susceptible isolates), with no cytotoxicity on mammalian cells (selectivity index of 73.97). Moreover, HP1 had activity against a metronidazole-resistant isolate (52% of viable trophozoites), and this effect was higher when tested with a low concentration of metronidazole (23% of viable trophozoites). Experiments demonstrated that all isolated compounds caused damage to the parasites' membrane (>90% of LDH release) and do not present a notable hemolytic effect, although HP2 and uliginosin B exhibited cytotoxicity against mammalian cells. Therefore, the analyzed molecules are promising prototypes for new antiprotozoal drugs, especially HP1, which seems to improve metronidazole's effect on a resistant T. vaginalis isolate.

  7. Antifungal, Phytotoxic, and Cytotoxic Activities of Metabolites from Epichloë bromicola, a Fungus Obtained from Elymus tangutorum Grass.

    PubMed

    Song, Qiu-Yan; Nan, Zhi-Biao; Gao, Kun; Song, Hui; Tian, Pei; Zhang, Xing-Xu; Li, Chun-Jie; Xu, Wen-Bo; Li, Xiu-Zhang

    2015-10-14

    The development of high-quality herbage is an important aspect of animal husbandry. Inoculating beneficial fungi onto inferior grass is a feasible strategy for producing new varieties of high-quality herbage. Epichloë bromicola is a candidate fungus that is isolated from Elymus tangutorum. A total of 17 metabolites, 1-17, were obtained from E. bromicola, and their biological activities were assayed. Metabolite 1 exhibited antifungal activities against Alternaria alternata, Fusarium avenaceum, Bipolaris sorokiniana, and Curvularia lunata. EC50 values ranged from 0.7 to 5.3 μM, which were better than the positive control, chlorothalonil. Metabolite 8 displayed obvious phytotoxic effects toward Lolium perenne and Poa crymophila seedlings, and it was as active as glyphosate. None of these isolated metabolites displayed cytotoxicity against Madin-Darby bovine kidney cells. The IC50 values were greater than 100 μM, and the metabolites increased the growth of the cells at a concentration of 12.5 μM. The bioassay indicated that E. bromicola may be a beneficial fungus for producing new varieties of herbage with various resistances. Additionally, metabolite 7, 3-(2'-(4″-hydroxyphenyl)acetoxy)-2S-methylpropanoic acid, is a new natural product, and its stereochemistry was determined by means of optical rotation computation and chemical reactions. PMID:26395226

  8. Antifungal, Phytotoxic, and Cytotoxic Activities of Metabolites from Epichloë bromicola, a Fungus Obtained from Elymus tangutorum Grass.

    PubMed

    Song, Qiu-Yan; Nan, Zhi-Biao; Gao, Kun; Song, Hui; Tian, Pei; Zhang, Xing-Xu; Li, Chun-Jie; Xu, Wen-Bo; Li, Xiu-Zhang

    2015-10-14

    The development of high-quality herbage is an important aspect of animal husbandry. Inoculating beneficial fungi onto inferior grass is a feasible strategy for producing new varieties of high-quality herbage. Epichloë bromicola is a candidate fungus that is isolated from Elymus tangutorum. A total of 17 metabolites, 1-17, were obtained from E. bromicola, and their biological activities were assayed. Metabolite 1 exhibited antifungal activities against Alternaria alternata, Fusarium avenaceum, Bipolaris sorokiniana, and Curvularia lunata. EC50 values ranged from 0.7 to 5.3 μM, which were better than the positive control, chlorothalonil. Metabolite 8 displayed obvious phytotoxic effects toward Lolium perenne and Poa crymophila seedlings, and it was as active as glyphosate. None of these isolated metabolites displayed cytotoxicity against Madin-Darby bovine kidney cells. The IC50 values were greater than 100 μM, and the metabolites increased the growth of the cells at a concentration of 12.5 μM. The bioassay indicated that E. bromicola may be a beneficial fungus for producing new varieties of herbage with various resistances. Additionally, metabolite 7, 3-(2'-(4″-hydroxyphenyl)acetoxy)-2S-methylpropanoic acid, is a new natural product, and its stereochemistry was determined by means of optical rotation computation and chemical reactions.

  9. Composition and potential anticancer activities of essential oils obtained from myrrh and frankincense.

    PubMed

    Chen, Yingli; Zhou, Chunlan; Ge, Zhendan; Liu, Yufa; Liu, Yuming; Feng, Weiyi; Li, Sen; Chen, Guoyou; Wei, Taiming

    2013-10-01

    The present study aimed to investigate the composition and potential anticancer activities of essential oils obtained from two species, myrrh and frankincense, by hydrodistillation. Using gas chromatography-mass spectrometry (GC-MS), 76 and 99 components were identified in the myrrh and frankincense essential oils, respectively, with the most abundant components, 2-Cyclohexen-1-one, 4-ethynyl-4-hydroxy-3,5,5-trimethyl- and n-Octylacetate, accounting for 12.01 and 34.66%, respectively. The effects of the two essential oils, independently and as a mixture, on five tumor cell lines, MCF-7, HS-1, HepG2, HeLa and A549, were investigated using the MTT assay. The results indicated that the MCF-7 and HS-1 cell lines showed increased sensitivity to the myrrh and frankincense essential oils compared with the remaining cell lines. In addition, the anticancer effects of myrrh were markedly increased compared with those of frankincense, however, no significant synergistic effects were identified. The flow cytometry results indicated that apoptosis may be a major contributor to the biological efficacy of MCF-7 cells. PMID:24137478

  10. Composition and potential anticancer activities of essential oils obtained from myrrh and frankincense

    PubMed Central

    CHEN, YINGLI; ZHOU, CHUNLAN; GE, ZHENDAN; LIU, YUFA; LIU, YUMING; FENG, WEIYI; LI, SEN; CHEN, GUOYOU; WEI, TAIMING

    2013-01-01

    The present study aimed to investigate the composition and potential anticancer activities of essential oils obtained from two species, myrrh and frankincense, by hydrodistillation. Using gas chromatography-mass spectrometry (GC-MS), 76 and 99 components were identified in the myrrh and frankincense essential oils, respectively, with the most abundant components, 2-Cyclohexen-1-one, 4-ethynyl-4-hydroxy-3,5,5-trimethyl- and n-Octylacetate, accounting for 12.01 and 34.66%, respectively. The effects of the two essential oils, independently and as a mixture, on five tumor cell lines, MCF-7, HS-1, HepG2, HeLa and A549, were investigated using the MTT assay. The results indicated that the MCF-7 and HS-1 cell lines showed increased sensitivity to the myrrh and frankincense essential oils compared with the remaining cell lines. In addition, the anticancer effects of myrrh were markedly increased compared with those of frankincense, however, no significant synergistic effects were identified. The flow cytometry results indicated that apoptosis may be a major contributor to the biological efficacy of MCF-7 cells. PMID:24137478

  11. Activity concentrations and dose rates from decorative granite countertops.

    PubMed

    Llope, W J

    2011-06-01

    The gamma radiation emitted from a variety of commercial decorative granites available for use in U.S. homes has been measured with portable survey meters as well as an NaI(Th) gamma spectrometer. The (40)K, U-nat, and (232)Th activity concentrations were determined using a full-spectrum analysis. The dose rates that would result from two different arrangements of decorative granite slabs as countertops were explored in simulations involving an adult anthropomorphic phantom.

  12. The influence of thoron on instruments measuring radon activity concentration.

    PubMed

    Michielsen, N; Bondiguel, S

    2015-11-01

    Thoron, the isotope 220 of radon, is a radionuclide whose concentration may influence the measurement of the activity concentration of (222)Rn in the air. If in the case of continuous and active sampling measuring instruments, using a pump for example, the influence of thoron on radon measurement is obvious and is taken into account in the apparatus, it is often assumed that in the case of a passive sampling, by diffusion through a filter for example, this thoron influence is negligible. This is due to the very short radioactive half-life of thoron, 55.6 s (3.82 d for (222)Rn), and the assumption that the diffusion time of thoron in the detection chamber is long enough beside that of the thoron half-life. The objective of this study is to check whether this assumption is true or not for different kinds of commercial electronic apparatus used to measure radon activity concentration from soil to dwellings. First of all, the devices were calibrated in activity concentration of radon, and then they were exposed to a controlled thoron atmosphere. The experiments concerning the thoron aimed to investigate the sensitivity to thoron in the radon measuring mode of the apparatus. Results of these experiments show that all devices have a very quick answer to thoron atmosphere, even though the sensitivities vary from one instrument to another. Results clearly show that this influence on radon measurement due to the thoron is observed also after the exposition because of the decay of (212)Pb and its progenies. In conclusion, the sensitivity to thoron in the radon measuring mode depends strongly on the type of instruments. The results of the present investigation show that for some apparatus, the influence of thoron cannot be disregarded especially when measuring radon in soil.

  13. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution.

    PubMed

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo; Muniz-Miranda, Maurizio

    2016-01-01

    Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by "activating" the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a restricted

  14. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution.

    PubMed

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo; Muniz-Miranda, Maurizio

    2016-01-01

    Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by "activating" the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a restricted

  15. Phytochemical concentrations and biological activities of Sorghum bicolor alcoholic extracts.

    PubMed

    Dia, Vermont P; Pangloli, Philipus; Jones, Lynsey; McClure, Angela; Patel, Anjali

    2016-08-10

    Sorghum is an important cereal with reported health benefits. The objectives of this study were to measure the biological activities of alcoholic extracts of ten sorghum varieties and to determine the association between the color of the extracts and their biological activities. Variation on concentrations of bioactives among sorghum varieties was observed with ethanolic extracts giving higher concentrations than methanolic extracts. The color of the extracts significantly correlated with the concentrations of bioactives and with nitric oxide scavenging activity. Freeze-dried ethanol extract is more potent than freeze-dried methanol extract and caused cytotoxicity to A27801AP and PTX-10 OVCA with ED50 values of 0.69 and 1.29 mg mL(-1), respectively. Pre-treatment of OVCA with ethanol extract led to chemosensitization to paclitaxel and the proliferation and colony formation of OVCA cells were reduced by 14.7 to 44.6% and 36.4 to 40.1%, respectively. Sorghum is a potential source of colorants with health promoting properties. This is the first report on the capability of sorghum alcoholic extracts to cause cytotoxicity and chemosensitize ovarian cancer cells in vitro. PMID:27406291

  16. Quantification of active pharmaceutical ingredient and impurities in sildenafil citrate obtained from the Internet

    PubMed Central

    Nutan, Mohammad T.; Dodla, Uday Krishna Reddy

    2014-01-01

    Background: The accessibility of prescription drugs produced outside of the United States, most notably sildenafil citrate (innovator product, Viagra®), has been made much easier by the Internet. Of greatest concern to clinicians and policymakers is product quality and patient safety. The US Food and Drug Administration (FDA) has issued warnings to potential buyers that the safety of drugs purchased from the Internet cannot be guaranteed, and may present a health risk to consumers from substandard products. Objective: The objective of this study was to determine whether generic sildenafil citrate tablets from international markets obtained via the Internet are equivalent to the US innovator product regarding major aspects of pharmaceutical quality: potency, accuracy of labeling, and presence and level of impurities. This will help identify aspects of drug quality that may impact public health risks. Methods: A total of 15 sildenafil citrate tablets were obtained for pharmaceutical analysis: 14 generic samples from international Internet pharmacy websites and the US innovator product. According to US Pharmacopeial guidelines, tablet samples were tested using high-performance liquid chromatography for potency of active pharmaceutical ingredient (API) and levels of impurities (impurities A, B, C, and D). Impurity levels were compared with International Conference on Harmonisation (ICH) limits. Results: Among the 15 samples, 4 samples possessed higher impurity B levels than the ICH qualification threshold, 8 samples possessed higher impurity C levels than the ICH qualification threshold, and 4 samples possessed more than 1% impurity quantity of maximum daily dose (MDD). For API, 6 of the samples failed to fall within the 5% assay limit. Conclusions: Quality assurance tests are often used to detect formulation defects of drug products during the manufacturing and/or storage process. Results suggest that manufacturing standards for sildenafil citrate generic drug

  17. Characterization of particulate matter concentrations during controlled indoor activities

    NASA Astrophysics Data System (ADS)

    Glytsos, T.; Ondráček, J.; Džumbová, L.; Kopanakis, I.; Lazaridis, M.

    2010-04-01

    Indoor sources have been identified as a major contributor to the increase of particle concentration in indoor environments. The work presented here is a study of the characteristics of particulate matter number size distribution and mass concentration under controlled indoor activities in a laboratory room. The objective is to characterize particulate matter concentrations indoors resulted under the influence of specific sources. Measurements were performed in an empty laboratory (period September-October 2006) using a GRIMM SMPS+C system (particle size range between 11.1 and 1083.3 nm), a DustTrak Aerosol Monitor (TSI) and a P-Trak Ultrafine Particle Counter (TSI). The studied indoor activities included candle burning, hot plate heating, water boiling, onion frying, vacuuming, hair drying, hair spraying, smoking and burning of incense stick. The AMANpsd computer algorithm was used to evaluate the modal structure of measured particle number size distribution data. Furthermore, the change of the particle number size distribution shape under the influence of different emission sources was studied versus time. Finally the particle emission rates were computed. High particle number concentrations were observed during smoking, onion frying, candle burning and incense stick burning. The highest particle mass concentrations were measured during smoking and hair spraying. The shift of the particle size distribution to larger diameters suggests the presence of strong coagulation effect during candle burning, incense stick burning, smoking and onion frying. The size distribution was mainly bimodal during onion frying and candle burning, whereas the size distribution remained unimodal during incense stick burning and smoking experiments.

  18. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution

    PubMed Central

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo

    2016-01-01

    Summary Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by “activating” the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a

  19. Murine cardiac images obtained with focusing pinhole SPECT are barely influenced by extra-cardiac activity

    NASA Astrophysics Data System (ADS)

    Branderhorst, Woutjan; van der Have, Frans; Vastenhouw, Brendan; Viergever, Max A.; Beekman, Freek J.

    2012-02-01

    Ultra-high-resolution SPECT images can be obtained with focused multipinhole collimators. Here we investigate the influence of unwanted high tracer uptake outside the scan volume on reconstructed tracer distributions inside the scan volume, for 99mTc-tetrofosmin myocardial perfusion scanning in mice. Simulated projections of a digital mouse phantom (MOBY) in a focusing multipinhole SPECT system (U-SPECT-II, MILabs, The Netherlands) were generated. With this system differently sized user-defined scan volumes can be selected, by translating the animal in 3D through the focusing collimators. Scan volume selections were set to (i) a minimal volume containing just the heart, acquired without translating the animal during scanning, (ii) a slightly larger scan volume as is typically applied for the heart, requiring only small XYZ translations during scanning, (iii) same as (ii), but extended further transaxially, and (iv) same as (ii), but extended transaxially to cover the full thorax width (gold standard). Despite an overall negative bias that is significant for the minimal scan volume, all selected volumes resulted in visually similar images. Quantitative differences in the reconstructed myocardium between gold standard and the results from the smaller scan volume selections were small; the 17 standardized myocardial segments of a bull's eye plot, normalized to the myocardial mean of the gold standard, deviated on average 6.0%, 2.5% and 1.9% for respectively the minimal, the typical and the extended scan volume, while maximum absolute deviations were respectively 18.6%, 9.0% and 5.2%. Averaged over ten low-count noisy simulations, the mean absolute deviations were respectively 7.9%, 3.2% and 1.9%. In low-count noisy simulations, the mean and maximum absolute deviations for the minimal scan volume could be reduced to respectively 4.2% and 12.5% by performing a short survey scan of the exterior activity and focusing the remaining scan time at the organ of interest. We

  20. Assessment of national systems for obtaining local acceptance of waste management siting and routing activities

    SciTech Connect

    Paige, H.W.; Lipman, D.S.; Owens, J.E.

    1980-07-01

    There is a rich mixture of formal and informal approaches being used in our sister nuclear democracies in their attempts to deal with the difficulties of obtaining local acceptance for siting of waste management facilities and activities. Some of these are meeting with a degree of success not yet achieved in the US. Although this survey documents and assesses many of these approaches, time did not permit addressing in any detail their relevance to common problems in the US. It would appear the US could benefit from a periodic review of the successes and failures of these efforts, including analysis of their applicability to the US system. Of those countries (Germany, Sweden, Switzerland, Japan, Belgium, and the US) who are working to a time table for the preparation of a high-level waste (HLW) repository, Germany is the only country to have gained local siting acceptance for theirs. With this (the most difficult of siting problems) behind them they appear to be in the best overall condition relative to waste management progress and plans. This has been achieved without a particularly favorable political structure, made up for by determination on the part of the political leadership. Of the remaining three countries studied (France, UK and Canada) France, with its AVM production facility, is clearly the world leader in the HLW immobilization aspect of waste management. France, Belgium and the UK appear to have the least favorable political structures and environments for arriving at waste management decisions. US, Switzerland and Canada appear to have the least favorable political structures and environments for arriving at waste management decisions.

  1. Effects of anesthesia with isoflurane on plasma concentrations of adrenocorticotropic hormone in samples obtained from the cavernous sinus and jugular vein of horses.

    PubMed

    Carmalt, James L; Duke-Novakovski, Tanya; Schott, Harold C; van der Kolk, Johannes H

    2016-07-01

    OBJECTIVE To determine effects of anesthesia on plasma concentrations and pulsatility of ACTH in samples obtained from the cavernous sinus and jugular vein of horses. ANIMALS 6 clinically normal adult horses. PROCEDURES Catheters were placed in a jugular vein and into the cavernous sinus via a superficial facial vein. The following morning (day 1), cavernous sinus blood samples were collected every 5 minutes for 1 hour (collection of first sample = time 0) and jugular venous blood samples were collected at 0, 30, and 60 minutes. On day 2, horses were sedated with xylazine hydrochloride and anesthesia was induced with propofol mixed with ketamine hydrochloride. Horses were positioned in dorsal recumbency. Anesthesia was maintained with isoflurane in oxygen and a continuous rate infusion of butorphanol tartrate. One hour after anesthesia was induced, the blood sample protocol was repeated. Plasma ACTH concentrations were quantified by use of a commercially available sandwich assay. Generalized estimating equations that controlled for horse and an expressly automated deconvolution algorithm were used to determine effects of anesthesia on plasma ACTH concentrations and pulsatility, respectively. RESULTS Anesthesia significantly reduced the plasma ACTH concentration in blood samples collected from the cavernous sinus. CONCLUSIONS AND CLINICAL RELEVANCE Mean plasma ACTH concentrations in samples collected from the cavernous sinus of anesthetized horses were reduced. Determining the success of partial ablation of the pituitary gland in situ for treatment of pituitary pars intermedia dysfunction may require that effects of anesthesia be included in interpretation of plasma ACTH concentrations in cavernous sinus blood. PMID:27347826

  2. User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part 2, Field tests

    USGS Publications Warehouse

    Vroblesky, Don A.

    2001-01-01

    Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

  3. Gastroprotective effect of alpha-pinene and its correlation with antiulcerogenic activity of essential oils obtained from Hyptis species

    PubMed Central

    Pinheiro, Marcelo de Almeida; Magalhães, Rafael Matos; Torres, Danielle Mesquita; Cavalcante, Rodrigo Cardoso; Mota, Francisca Sheila Xavier; Oliveira Coelho, Emanuela Maria Araújo; Moreira, Henrique Pires; Lima, Glauber Cruz; Araújo, Pamella Cristina da Costa; Cardoso, José Henrique Leal; de Souza, Andrelina Noronha Coelho; Diniz, Lúcio Ricardo Leite

    2015-01-01

    Background: Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances. Objective: The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice. Materials and Methods: Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis. Results: α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98). Conclusion: Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed. PMID:25709221

  4. Determination of thorium concentrations and activity ratios in silicate rocks by alpha spectrometry.

    PubMed

    dos Santos, R N; Marques, L S; Nicolai, S H A; Ribeiro, F B

    2004-01-01

    A detailed radiochemical procedure for alpha spectrometry measurements of thorium concentrations and of 230Th/232Th activity ratios in silicates is presented. The Th behaviour, during each step of the chemical process, was investigated by using a 234Th tracer, which is a gamma-ray emitter. The described chemical processing provides relatively high thorium yields, which varied between 56% and 88%, in the analysis of GB-1 (granite) and BB-1 (basalt) Brazilian geological standards. Also, the application of the established radiochemical method allowed a determination of both Th concentrations and activity ratios with high reproducibility, on the order of 2%. The estimation of the concentration result accuracy is also about 2%, which was calculated by using published data obtained from neutron activation analysis as reference values.

  5. Sedimentology models from activity concentration measurements: application to the "Bay of Cadiz" Natural Park (SW Spain).

    PubMed

    Ligero, R A; Vidal, J; Meléndez, M J; Hamani, M; Casas-Ruiz, M

    2009-03-01

    A previous study on seabed sediments of the Bay of Cadiz (SW of Spain) enabled us to identify several relations between sedimentological variables and activity concentrations of environmental radionuclides such as (137)Cs, (226)Ra, (232)Th and (40)K. In this paper the study has been extended to a large neighbouring inter-tidal area in order to establish if the above mentioned models can be generalized. As a result we have determined that the measured activity concentrations are closely to the values predicted by the theoretical models (correlation coefficient range=0.85-0.93). Furthermore, the proposal model for granulometric facies as a function of activity concentrations of the abovementioned radionuclides provides for the sediments distribution a representation which agrees with the values of the tidal energy distribution obtained using numeric models calibrated with experimental data from current meters and water level recorders. PMID:19136180

  6. [Identification of a novel lytic bacteriophage obtained from clinical MRSA isolates and evaluation of its antibacterial activity].

    PubMed

    Sahin, Fikret; Karasartova, Djursun; Ozsan, T Murat; Gerçeker, Devran; Kıyan, Mehmet

    2013-01-01

    Multidrug-resistant bacteria particularly MRSA is well known as a worldwide problem. Since the rate of development of novel antimicrobial agents has been slowed down during the last years, there have been a need for the exploration of alternative solutions for the treatment of resistant bacterial infections. Treatment of infections by bacteriophages (phages) that specifically kill the infecting pathogen, i.e. by the process known as phage therapy, is considered as a possible approach to treat multidrug resistant bacteria. Phage treatment has also been considered to treat Staphylococcus aureus infections. This study was aimed to evaluate the antibacterial and cytotoxic activities of a new lytic phage obtained from clinical MRSA strains. This lytic phage named as f LizAnk was obtained during the phage infectivity studies performed with 13 lysogenic phages against MRSA strains. The antibacterial activity of the f LizAnk phage was determined in vitro in BHI (Brain Heart Infusion) and LB (Leuria Bertani) broths and the in vivo antibacterial activity against MRSA strains and possible cytotoxic effect against mammalian cells were tested on fibroblastic cell cultures (3T3). This study was conducted using 20 MRSA strains isolated from hospitalized patients. Identification of the isolates was performed by conventional methods and methicillin resistance was detected with oxacillin disk diffusion test and mecA gene detection by PCR. The method described by Kaneko et al. [Biosci Biotechnol Biochem 1997; 61(11): 1960-2] was used with some modifications, for induction and isolation of the phages. In vitro studies indicated that this phage killed the six different MRSA strains (in 107 cfu/ml concentrations) in 8 hours, and this powerful lytic effect was similar in both of the liquid media. In vivo studies were performed by using cell cultures prepared in microplates, and the wells have been inoculated with only phage, phage + MRSA mixture, and only MRSA. The cells were then

  7. [Phospholipase, proteinase and hemolytic activities of Candida albicans isolates obtained from clinical specimens].

    PubMed

    Yenişehirli, Gülgün; Bulut, Yunus; Tunçoglu, Ebru

    2010-01-01

    This study was aimed to determine the phospholipase, proteinase and hemolytic activities of Candida albicans strains isolated from clinical specimens. A total of 147 C. albicans strains isolated from blood (n = 29), respiratory specimens (n = 44), urine (n = 52), pus (n = 17) and stool (n = 5) were included in the study. Proteinase and phospholipase activities were determined in 81% and 76% of C. albicans isolates, respectively. All C. albicans isolates revealed beta-hemolytic activity on Sabouraud dextrose agar supplemented with 7% fresh sheep blood and 3% glucose. Phospholipase and proteinase positivity were highest among the respiratory isolates. Proteinase activity of respiratory (93%) and blood (83%) isolates were statistically significantly higher than that of urine (77%; p = 0.032), pus (65%; p = 0.007) and stool isolates (60%; p = 0.026). While phospholipase activity showed statistically significant difference between respiratory (84%) and pus (53%) isolates (p = 0.014), no statistically significant difference was determined for blood (79%), urine (75%) and stool (80%) isolates (p > 0.05). Two blood isolates with 4+ proteinase activity and 3 urine isolates with 3+ proteinase activity were phospholipase negative. One urine isolate with 4+ phospholipase activity and 4 with 3+ phospholipase activity were proteinase negative. Phospholipase and proteinase negative 1 isolate from stool and 1 isolate from pus were found to have 4+ hemolytic activity. In conclusion, besides proteinase and phospholipase enzyme activities, hemolytic activity may play an important role for the C.albicans infections. The pathogenetic role of these virulence factors should be evaluated by further clinical studies.

  8. Antioxidant and antifungal activity of different extracts obtained from aerial parts of Inula crithmoides L.

    PubMed

    Bucchini, Anahi; Ricci, Donata; Messina, Federica; Marcotullio, Maria Carla; Curini, Massimo; Giamperi, Laura

    2015-01-01

    The total phenolic content, antioxidant and antifungal activities of three Inula crithmoides extracts (n-hexane, methylene chloride and MeOH) were investigated. The methanolic extract showed the highest total phenolic content. In the DPPH assay, the methanolic and hexane extracts exhibited the highest DPPH-radical scavenging activity; in the 5-lipoxygenase assay, the hexane extract showed greater inhibitory effect with an IC50 similar to that of Trolox and ascorbic acid. The antifungal activity of the methanolic extract revealed a higher activity against Phytophtora cryptogea and Alternaria solani. PMID:25426874

  9. Further studies of activation-inactivation coupling in Myxicola axons. Insensitivity to changes in calcium concentration.

    PubMed Central

    Schauf, C L; Davis, F A

    1975-01-01

    In Myxicola axons subjected to moderate depolarizations the sodium inactivation time constants obtained from the decay of sodium current during a maintained depolarizatin (TSh) are substantially smaller than inactivation time constants determined at the same potential from the effect of changes in the duration of conditioning prepulses (Tph). This report extends these observations to positive membrane potentials and demonstrates that for sufficiently large depolarizations TSh and Tph become comparable. The ratio of inactivation time constants, Tph/TSh, is unaffected by changes in [Ca++] provided total divalent cation concentration is maintained constant, while changes in total divalent ion concentrations produce simple voltage shifts comparable to those obtained from measurement of membrane sodium or potassium conductances. Sodium inactivation delay was quantitatively determined as a function of membrane potential, and found to be similarly unaffected by changes in [Ca++] at constant total divalent ion concentration. Inactivation delay is, however, directly proportional to the activation rate constant over a wide range of potentials. PMID:1201328

  10. Dimerization in Highly Concentrated Solutions of Phosphoimidazolide Activated Mononucleotides

    NASA Technical Reports Server (NTRS)

    Kanavarioti, Anastassia

    1997-01-01

    Phosphoimidazolide activated ribomononucleotides (*pN) are useful substrates for the non-enzymatic synthesis of polynucleotides. However, dilute neutral aqueous solutions of *pN typically yield small amounts of dimers and traces of polymers; most of *pN hydrolyzes to yield nucleoside 5'-monophosphate. Here we report the self-condensation of nucleoside 5'-phosphate 2- methylimidazolide (2-MeImpN with N = cytidine, uridine or guanosine) in the presence of Mg2(+) in concentrated solutions, such as might have been found in an evaporating lagoon on prebiotic Earth. The product distribution indicates that oligomerization is favored at the expense of hydrolysis. At 1.0 M, 2-MelmpU and 2-MelmpC produce about 65% of oligomers including 4% of the 3',5'-Iinked dimer. Examination of the product distribution of the three isomeric dimers in a self-condensation allows identification of reaction pathways that lead to dimer formation. Condensations in a concentrated mixture of all three nucleotides (U,C,G mixtures) is made possible by the enhanced solubility of 2-MeImpG in such mixtures. Although percent yield of intemucleotide linked dimers is enhanced as a function of initial monomer concentration, pyrophosphate dimer yields remain practically unchanged at about 20% for 2-MelmpU, 16% for 2-MeImpC and 25% of the total pyrophosphate in the U,C,G mixtures. The efficiency by which oligomers are produced in these concentrated solutions makes the evaporating lagoon scenario a potentially interesting medium for the prebiotic synthesis of dimers and short RNAs.

  11. Theta activity and meditative states: spectral changes during concentrative meditation.

    PubMed

    Baijal, Shruti; Srinivasan, Narayanan

    2010-02-01

    Brain oscillatory activity is associated with different cognitive processes and plays a critical role in meditation. In this study, we investigated the temporal dynamics of oscillatory changes during Sahaj Samadhi meditation (a concentrative form of meditation that is part of Sudarshan Kriya yoga). EEG was recorded during Sudarshan Kriya yoga meditation for meditators and relaxation for controls. Spectral and coherence analysis was performed for the whole duration as well as specific blocks extracted from the initial, middle, and end portions of Sahaj Samadhi meditation or relaxation. The generation of distinct meditative states of consciousness was marked by distinct changes in spectral powers especially enhanced theta band activity during deep meditation in the frontal areas. Meditators also exhibited increased theta coherence compared to controls. The emergence of the slow frequency waves in the attention-related frontal regions provides strong support to the existing claims of frontal theta in producing meditative states along with trait effects in attentional processing. Interestingly, increased frontal theta activity was accompanied reduced activity (deactivation) in parietal-occipital areas signifying reduction in processing associated with self, space and, time.

  12. Metal concentration and antioxidant activity of edible mushrooms from Turkey.

    PubMed

    Sarikurkcu, Cengiz; Tepe, Bektas; Kocak, Mehmet Sefa; Uren, Mehmet Cemil

    2015-05-15

    This study presents information on the antioxidant activity and heavy metal concentrations of Polyporus sulphureus, Macrolepiota procera, Lycoperdon perlatum and Gomphus clavatus mushrooms collected from the province of Mugla in the South-Aegean Region of Turkey. Antioxidant activities of mushroom samples were evaluated by four complementary tests. All tests showed L. perlatum and G. clavatus to possess extremely high antioxidant potential. Antioxidant activity of the samples was strongly correlated with total phenolic-flavonoid content. In terms of heavy metal content, L. perlatum exceeded the legal limits for daily intake of Pb, Fe, Mn, Cr, Ni and Co contents (0.461, 738.00, 14.52, 1.27, 1.65, 0.417 mg/day, respectively) by a 60-kg consumer. Co contents of M. procera (0.026 mg/day) and P. sulphureus (0.030 mg/day) and Cd contents of G. clavatus (0.071 mg/day) were also above the legal limits. According to these results, L. perlatum should not be consumed, despite the potentially beneficial antioxidant activity. Additionally, M. procera and G. clavatus should not be consumed daily due to their high levels of Cd and Co.

  13. Comparison of electron concentrations in the ionospheric E-layer maximum in spring conditions obtained by calculations and Moscow ionosonde measurements

    NASA Astrophysics Data System (ADS)

    Pavlov, A. V.; Pavlova, N. M.

    2015-03-01

    The electron concentrations in the ionospheric E-layer maximum NmE, as measured by the Moscow ionosonde, are compared with the results of theoretical calculations of NmE for geomagnetically quiet conditions at low solar activity on April 1, 1986, and April 6, 1996, moderate solar activity on April 9, 1978, and April 6, 1998, and high solar activity on April 20, 1980, and April 15, 1991. On the basis of this comparison, a correction of the model flux of solar X-ray radiation is proposed. The discovered variability of the correction factors manifests the influence of solar X-ray radiation flux variations on NmE variability. The dependence of the influence of the neutral constituents ionization by photoelectrons on NmE on the solar activity level is studied.

  14. Biological evaluation of synthesized allicin and its transformation products obtained by microwaves in methanol: antioxidant activity and effect on cell growth

    PubMed Central

    Ilić, Dušica P.; Stojanović, Sanja; Najman, Stevo; Nikolić, Vesna D.; Stanojević, Ljiljana P.; Tačić, Ana; Nikolić, Ljubiša B.

    2015-01-01

    Allicin is the most biologically active substance present in garlic. It can be synthesized or obtained by extraction of fresh garlic. Transformation products of allicin are also biologically active. The aim of this study was to examine the antioxidant activity of synthesized allicin and its transformation products obtained using microwaves in methanol at 55 °C as well as their effect on HeLa cells growth. The antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) test. The effect on HeLa cells growth was determined by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) test. For MTT test, allicin and its transformation products were dispersed in carmellose sodium solution and examined in concentrations ranging from 0.3 μg/mL to 3 mg/mL. Allicin showed stronger antioxidant activity than the transformation products. A maximum degree of neutralization of DPPH radicals, about 90%, was reached when the concentration of allicin was 2 mg/mL, with an EC50 (concentration of sample which is required for reduction of the initial concentration DPPH radicals to 50%) value of 0.37 mg/mL. In our study, allicin and its transformation products were not cytotoxic to HeLa cells under the examined conditions. The highest concentration of allicin and its transformation products had a slight antiproliferative effect, with a more pronounced effect of allicin, which reflected on the morphology of HeLa cells. The examined substances are safe to use on epithelial cells at concentrations up to 3 mg/mL when applied in carmellose sodium solution. Using carmellose sodium as a dispersing agent could be recommended as a good approach for testing liposoluble substances in liquid cell cultures. PMID:26019632

  15. The influence of particle size on radionuclide activity concentrations in Tejo River sediments.

    PubMed

    Madruga, M J; Silva, L; Gomes, A R; Libânio, A; Reis, M

    2014-06-01

    Sediment samples from Tejo River were analyzed for (228)Ra, (226)Ra, (137)Cs and (40)K by HPGe gamma spectrometry. The activity concentration data were statistically analyzed. The activity concentrations values were in the range of about two orders of magnitude for each radionuclide. The influence of the particle size on the radionuclide concentrations was observed. The different environmental origins of the radionuclides (228)Ra, (226)Ra, (137)Cs and (40)K, in the sediments were demonstrated through correlation analysis. Cluster analysis showed a close relationship between (228)Ra and (226)Ra and a different behavior for (40)K. The data obtained in this study provides useful information on the background radioactivity of the studied area and can be further used for radiological mapping of the Tejo River. PMID:24561724

  16. The influence of particle size on radionuclide activity concentrations in Tejo River sediments.

    PubMed

    Madruga, M J; Silva, L; Gomes, A R; Libânio, A; Reis, M

    2014-06-01

    Sediment samples from Tejo River were analyzed for (228)Ra, (226)Ra, (137)Cs and (40)K by HPGe gamma spectrometry. The activity concentration data were statistically analyzed. The activity concentrations values were in the range of about two orders of magnitude for each radionuclide. The influence of the particle size on the radionuclide concentrations was observed. The different environmental origins of the radionuclides (228)Ra, (226)Ra, (137)Cs and (40)K, in the sediments were demonstrated through correlation analysis. Cluster analysis showed a close relationship between (228)Ra and (226)Ra and a different behavior for (40)K. The data obtained in this study provides useful information on the background radioactivity of the studied area and can be further used for radiological mapping of the Tejo River.

  17. The anticancer activity of dichloromethane crude extract obtained from Calea pinnatifida

    PubMed Central

    Marchetti, Gabriela M; Silva, Karina A; Santos, Arianny N; Sousa, Ilza MO; Tinti, Sirlene V; Figueira, Glyn M; Foglio, Mary A; Carvalho, João E

    2012-01-01

    The genus Calea is reported for many biological activities such as antiinflammatory, antiplasmodial, antifungal, antimicrobial, and cytotoxic activities. Most of the pharmacological activities are credited to germacranolides, a sesquiterpene lactone common to this genus. Dried aerial parts of Calea pinnatifida Banks were extracted with dichloromethane, which generated the dichloromethane crude extract (DCE). The main purpose of this study was to evaluate the anticancer activity of DCE performed in sulforhodamine B cytotoxicity in vitro assay against human cancer cell lines and in vivo Ehrlich models. The DCE showed a high potency and selectivity for the melanoma and kidney cell line. Two in vivo assays were also conducted in the Ehrlich ascites tumor and Ehrlich solid tumor. In the Ehrlich ascites tumor assay, the treatment with DCE increased survival rates at the highest dose (200 mg/kg). Interestingly, in the Ehrlich solid tumor, by increasing the number of treatments from one to three times a week, the tumor growth was inhibited by a lower dose (100 mg/kg). These results encouraged follow-up studies with C. pinnatifida in order to identify the active principles and to determine the anticancer mechanism of action. PMID:27186128

  18. Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

    NASA Astrophysics Data System (ADS)

    Mikulska, Anna; Filipowska, Joanna; Osyczka, Anna; Nowakowska, Maria; Szczubiałka, Krzysztof

    2014-12-01

    Polymeric surfaces suitable for cell culture (DR/Pec) were constructed from diazoresin (DR) and pectin (Pec) in a form of ultrathin films using the layer-by-layer (LbL) technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs) to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins) was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP) activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2) to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2

  19. Quantification of the activity of biomolecules in microarrays obtained by direct laser transfer.

    PubMed

    Dinca, V; Ranella, A; Farsari, M; Kafetzopoulos, D; Dinescu, M; Popescu, A; Fotakis, C

    2008-10-01

    The direct-writing technique laser-induced forward transfer has been employed for the micro-array printing of liquid solutions of the enzyme horseradish peroxidase and the protein Titin on nitrocellulose solid surfaces. The effect of two UV laser pulse lengths, femtosecond and nanosecond has been studied in relation with maintaining the activity of the transferred biomolecules. The quantification of the active biomolecules after transfer has been carried out using Bradford assay, quantitative colorimetric enzymatic assay and fluorescence techniques. Spectrophotometric measurements of the HRP and the Titin activity as well as chromatogenic and fluorescence assay studies have revealed a connection between the properties of the deposited, biologically active biomolecules, the experimental conditions and the target composition. The bioassays have shown that up to 78% of the biomolecules remained active after femtosecond laser transfer, while this value reduced to 54% after nanosecond laser transfer. The addition of glycerol in a percentage up to 70% in the solution to be transferred has contributed to the stabilization of the micro-array patterns and the increase of their resolution.

  20. Human GV oocytes generated by mitotically active germ cells obtained from follicular aspirates

    PubMed Central

    Ding, Xinbao; Liu, Guishu; Xu, Bo; Wu, Changqing; Hui, Ning; Ni, Xin; Wang, Jian; Du, Meirong; Teng, Xiaoming; Wu, Ji

    2016-01-01

    Human female germline stem cells (FGSCs) have opened new opportunities for understanding human oogenesis, delaying menopause, treating infertility, and providing a new strategy for preserving fertility. However, the shortage of adult human ovaries tissues available impedes their future investigations and clinical applications. Here, we have established FGSC lines from scarce ovarian cortical tissues that exist in follicular aspirates (faFGSCs), which are produced and discarded in in vitro fertilization centers worldwide. The faFGSCs have characteristics of germline stem cells involved in the gene expression profile, growth characteristics, and a normal karyotype consistent with that of FGSCs obtained from ovarian cortexes surgically removed from patients (srFGSCs). Furthermore, faFGSCs have developmental potentials including spontaneous differentiation into oocytes under feeder-free conditions, communicating with granulosa cells by gap junctions and paracrine factors, entering meiosis after RA induction, as well as forming follicles after injection into human ovarian cortical tissues xenografted into adult immunodeficient female mice. Lastly, we developed a strategy guiding FGSCs differentiated into germinal vesicle (GV) stage oocytes in vitro and revealed their developmental mechanisms. Our study not only provides a new approach to obtain human FGSCs for medical treatment, but also opens several avenues to investigate human oogenesis in vitro. PMID:27357640

  1. Chemical compositions and antibacterial activity of extracts obtained from the inflorescences of Cirsium canum (L.) all.

    PubMed

    Kozyra, Małgorzata; Biernasiuk, Anna; Malm, Anna; Chowaniec, Marcin

    2015-01-01

    The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacilluscereus and Bacillus subtilis belonging to opportunistic microorganisms.

  2. Chemical compositions and antibacterial activity of extracts obtained from the inflorescences of Cirsium canum (L.) all.

    PubMed

    Kozyra, Małgorzata; Biernasiuk, Anna; Malm, Anna; Chowaniec, Marcin

    2015-01-01

    The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacilluscereus and Bacillus subtilis belonging to opportunistic microorganisms. PMID:25855328

  3. Evidence for Synchronicity of Lightning Activity in Spatially Remote Thunderstorms Obtained from Space Shuttle Observations

    NASA Astrophysics Data System (ADS)

    Yair, Y.; Aviv, R.; Ravid, G.; Yaniv, R.; Ziv, B.; Price, C.

    2005-12-01

    Visual observations by space shuttle astronauts detailed a phenomenon in which spatially distant thunderstorm cells seemed to reciprocally "ignite" lightning flashes in a semi-cyclic sequence. We report the quantitative analysis of lightning observations conducted within the framework of the MEIDEX-sprite campaign on board the space shuttle Columbia in January 2003 [Yair et al., 2003]. We analyzed video footage of 6 storm systems with varying flash rates, which occurred over Africa, South America, Australia and the Pacific Ocean. It is found that when the storm flash rate was high, lightning activity in horizontally remote electrically active cells became clustered, with bursts of nearly simultaneous activity separated by periods of quiet. The recurrence time was ~2.5 seconds, close to the time delay between consecutive signals in the SR range previously reported [Fallekrug, 1995]. We propose that this behavior is similar to the collective dynamics of a network of weakly coupled limit-cycle oscillators [Strogatz, 2000]. Thunderstorm cells embedded within a mesoscale convective system (MCS) constitute such a network, and their lightning frequency is best described in terms of phase-locking of a globally coupled array [Kourtchatov et al., 1995]. The dominant network hub in such an MCS is the thunderstorm cell with the highest flash rate, which affects the lightning activity of neighboring cells. Comparison of basic parameters of the lightning network with predictions of random graph models reveals that the network cannot be described by the classical random graph model [Erdos and Renyi, 1960], but is more compatible with generalized random graphs with prescribed degree distribution [Newman et al., 2001] that exhibit a high clustering coefficient and small average path lengths. Such networks are capable of supporting fast response, synchronization and coherent oscillations. Several physical mechanisms are suggested to explain this phenomenon.

  4. Biomass based activated carbon obtained from sludge and sugarcane bagasse for removing lead ion from wastewater.

    PubMed

    Tao, Hu-Chun; Zhang, He-Ran; Li, Jin-Bo; Ding, Wen-Yi

    2015-09-01

    Sewage sludge and bagasse were used as raw materials to produce cheap and efficient adsorbent with great adsorption capacity of Pb(2+). By pyrolysis at 800 °C for 0.5 h, the largest surface area (806.57 m(2)/g) of the adsorbent was obtained, enriched with organic functional groups. The optimal conditions for production of the adsorbent and adsorption of Pb(2+) were investigated. The results of adsorb-ability fitted the Langmuir isotherm and pseudo-second-order model well. The highest Pb(2+) (at pH = 4.0) adsorption capacity was achieved by treating with 60% (v/v) HNO3. This is a promising approach for metal removal from wastewater, as well as recycling sewage sludge and bagasse to ease their disposal pressure.

  5. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense)

    PubMed Central

    Chen, Yong-Feng; Jiang, Wen-wen; Zhang, Shi-qi; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→]n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2−∙ clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree. PMID:27446223

  6. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense).

    PubMed

    Chen, Yong-Feng; Jiang, Wen-Wen; Zhang, Shi-Qi; Kan, Jian-Quan; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→] n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2 (-∙) clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree.

  7. Antioxidant Activity and Characterization of One New Polysaccharide Obtained from Perigord Truffle (Tuber huidongense).

    PubMed

    Chen, Yong-Feng; Jiang, Wen-Wen; Zhang, Shi-Qi; Kan, Jian-Quan; Liang, Yong

    2016-01-01

    As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6)  α-D-Glcp (1→] n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2 (-∙) clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree. PMID:27446223

  8. Antithrombotic activity of fractions and components obtained from raspberry leaves (Rubus chingii).

    PubMed

    Han, Na; Gu, Yuhong; Ye, Chun; Cao, Yan; Liu, Zhihui; Yin, Jun

    2012-05-01

    The 70% ethanol fraction from an aqueous extract of raspberry leaves was shown to be the most antithrombotic fraction in in vitro and in vivo tests. The total flavonoids and phenolics in this fraction were 0.286g/g and 0.518g/g by colorimetry. Six compounds, including salicylic acid, kaempferol, quercetin, tiliroside, quercetin 3-O-β-d-glucopyranoside and kaempferol 3-O-β-d-glucopyranoside, were isolated from the active fraction. Among them, kaempferol, quercetin and tiliroside obviously delayed plasma recalcification time (PRT) in blood.

  9. INVESTIGATION OF FLY ASH AND ACTIVATED CARBON OBTAINED FROM PULVERIZED COAL BOILERS

    SciTech Connect

    Edward K. Levy; Christopher Kiely

    2005-11-01

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addresses the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addresses the possible connection between SCR reactors, fly ash properties and Hg capture. The project is determining the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed are also being determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control, are being analyzed to determine the effect of SCR on the ash.

  10. Investigation of Fly Ash and Activated Carbon Obtained from Pulverized Coal Boilers

    SciTech Connect

    Edward K. Levy; Christopher Kiely; Zheng Yao

    2006-08-31

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addressed the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addressed the possible connection between SCR reactors, fly ash properties and Hg capture. The project has determined the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed have also been determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control have been analyzed in an effort to determine the effects of SCR on the ash.

  11. INVESTIGATION OF FLY ASH AND ACTIVATED CARBON OBTAINED FROM PULVERIZED COAL BOILERS

    SciTech Connect

    Edward K. Levy; Christopher Kiely

    2004-11-01

    One of the techniques for Hg capture in coal-fired boilers involves injection of activated carbon (AC) into the boiler downstream of the air preheater. Hg is adsorbed onto the AC particles and fly ash, which are then both removed in an electrostatic precipitator or baghouse. This project addresses the issues of Hg on activated carbon and on fly ash from a materials re-use point of view. It also addresses the possible connection between SCR reactors, fly ash properties and Hg capture. The project is determining the feasibility of separating AC from fly ash in a fluidized bed and of regenerating the separated AC by heating the AC to elevated temperatures in a fluidized bed. The temperatures needed to drive off the Hg from the ash in a fluidized bed are also being determined. Finally, samples of fly ash from power plants with SCR reactors for NO{sub x} control, are being analyzed to determine the effect of SCR on the ash. These analyses will also determine the properties of ash which are important for Hg capture.

  12. In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates.

    PubMed

    Menezes, C B A; Silva, B P; Sousa, I M O; Ruiz, A L T G; Spindola, H M; Cabral, E; Eberlin, M N; Tinti, S V; Carvalho, J E; Foglio, M A; Fantinatti-Garboggini, F

    2013-01-01

    Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

  13. In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates

    PubMed Central

    Menezes, C.B.A.; Silva, B.P.; Sousa, I.M.O.; Ruiz, A.L.T.G.; Spindola, H.M.; Cabral, E.; Eberlin, M.N.; Tinti, S.V.; Carvalho, J.E.; Foglio, M.A.; Fantinatti-Garboggini, F.

    2012-01-01

    Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed. PMID:23090123

  14. Antioxidant activities of a polyglucuronic acid sodium salt obtained from TEMPO-mediated oxidation of xanthan.

    PubMed

    Delattre, C; Pierre, G; Gardarin, C; Traikia, M; Elboutachfaiti, R; Isogai, A; Michaud, P

    2015-02-13

    A xanthouronic acid sodium salt called xanthouronan was produced from xanthan by regioselective oxidation with NaOCl/NaBr using 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) as catalyst. The efficiency of the one pot TEMPO-mediated oxidation was confirmed by HPAEC-PAD, (13)C NMR, and FT-IR. The oxidation degree was close to 98% and the mass yield of this new polyglucuronic acid was higher than 90% (w/w). The macromolecular characterization of xanthouronan using SEC-MALLS showed a molecular size reduced by a third due to the oxidation treatment and the degree of polymerization (DP) of the xanthouronan form was about 665. The evaluation of the enzymatic degradation of this C-6 carboxylated xanthan by various polysaccharide hydrolases and one polysaccharide lyase showed its high resistant to biodegradation. The antioxidant activity of xanthouronan was also tested by using the 2,2'-diphenyl-1-picrylhydrazyle (DPPH) and hydroxyl radical procedures. At 1 g/L, xanthouronan presented 75% of the ascorbic acid antioxidant activity.

  15. Assessment of Parasitic Activity of Fusarium Strains Obtained from a Heterodera schachtii-Suppressive Soil

    PubMed Central

    Gao, Xuebiao; Yin, Bei; Borneman, James; Becker, J. Ole

    2008-01-01

    This study assessed the potential impact of various Fusarium strains on the population development of sugarbeet cyst nematodes. Fungi were isolated from cysts or eggs of Heterodera schachtii Schmidt that were obtained from a field suppressive to that nematode. Twenty-six strains of Fusarium spp. were subjected to a phylogenic analysis of their rRNA-ITS nucleotide sequences. Seven genetically distinct Fusarium strains were evaluated for their ability to influence population development of H. schachtii and crop performance in greenhouse trials. Swiss chard (Beta vulgaris) seedlings were transplanted into fumigated field soil amended with a single fungal strain at 1,000 propagules/g soil. One week later, the soil was infested with 250 H. schachtii J2/100 cm3 soil. Parasitized eggs were present in all seven Fusarium treatments at 1,180 degree-days after fungal infestation. The percentage of parasitism ranged from 17 to 34%. Although the most efficacious F. oxysporum strain 471 produced as many parasitized eggs as occurred in the original suppressive soil, none of the Fusarium strains reduced the population density of H. schachtii compared to the conducive check. This supports prior results that Fusarium spp. were not the primary cause of the population suppression of sugarbeet cyst nematodes at this location. PMID:19259511

  16. Photocatalytic Activity of TiO2 Thin Films Obtained by the Sputtering RF in Wastewater

    NASA Astrophysics Data System (ADS)

    Cardona Bedoya, Jairo Armando; Sanchez Velandia, Wilmer Asmed; Delgado Rosero, Miguel Iban; Florido Cuellar, Alex Enrique; Zelaya Angel, Orlando; Mendoza Alvarez, Julio G.

    2011-03-01

    The photocatalytic activity of Ti O2 thin films in wastewater, under an UV irradiation, is studied. The films were prepared on corning glass substrates by the sputtering RF technique. We present evidence on the photocatalytic degradation, carried out by advanced oxidation processes (AOPs) in domestic wastewater pretreated with UASB (upflow anaerobic sludge blanket) reactors. Ti O2 films were illuminated with ultraviolet light during a time of 4 hours (λ ≅ 264 nm). We could see the effect of degraded operation in the absorbance measurement using UV-VIS spectrophotometry. The results show an increased rate of degradation of the wastewater by 30% compared to the values reflected biologically treated wastewater by anaerobic reactors.

  17. Uncommon Trimethoxylated Flavonol Obtained from Rubus rosaefolius Leaves and Its Antiproliferative Activity.

    PubMed

    Petreanu, Marcel; Ferreira, Emili Kamila; Sagaz, Ana Paula M; Vendramini-Costa, Débora B; Ruiz, Ana Lúcia T G; De Carvalho, João Ernesto; Campos, Adriana; Cechinel Filho, Valdir; Delle Monache, Franco; Niero, Rivaldo

    2015-01-01

    This study shows the evaluation the antiproliferative effect of the extract, fractions, and uncommon compounds isolated from R. rosaefolius leaves. The compounds were identified by conventional spectroscopic methods such as NMR-H(1) and C(13) and identified as 5,7-dihydroxy-6,8,4'-trimethoxyflavonol (1), 5-hydroxy-3,6,7,8,4'-pentamethoxyflavone (2), and tormentic acid (3). Both hexane and dichloromethane fractions showed selectivity for multidrug-resistant ovary cancer cell line (NCI-ADR/RES) with total growth inhibition values of 11.1 and 12.6 μg/ml, respectively. Compound 1 also showed selective activity against the same cell line (18.8 μg/ml); however, it was especially effective against glioma cells (2.8 μg/ml), suggesting that this compound may be involved with the in vitro antiproliferative action. PMID:26788108

  18. Platelet activating factor raises intracellular calcium ion concentration in macrophages

    PubMed Central

    1986-01-01

    Peritoneal cells from thioglycollate-stimulated mice were allowed to adhere to coverglasses for 2 h to give a dense monolayer of adherent cells greater than 95% of which were macrophages. After incubation with the tetra-acetoxymethyl ester of quin2, coverglasses were rinsed with Ca2+-free saline, oriented at a 45 degree angle in square cuvettes containing a magnetically driven stir bar, and analyzed for changes in quin2 fluorescence in a spectrofluorimeter. Such fluorescence, taken as an indication of intracellular calcium ion concentration ([Ca2+]i), increased as exogenous calcium ion concentration ([Ca2+]o) was raised to 1 mM. At [Ca2+]o approximately equal to 10 microM, [Ca2+]i = 72 +/- 14 nM (n = 26); at [Ca2+]o = 1 mM, [Ca2+]i = 140-220 nM, levels not increased by N, N, N', N'-tetrakis (2-pyridylmethyl) ethylenediamine, a membrane-permeant chelator of heavy metals than can quench quin2. Addition of mouse alpha + beta fibroblast interferon, lipopolysaccharide, thrombin, collagen, vasopressin, ADP, compound 48/80, or U46619 did not change [Ca2+]i. However, addition of platelet activating factor (PAF) (2-20 ng/ml) raised [Ca2+]i by 480 nM within 1 min if [Ca2+]o = 1 mM. In the presence of 5 mM EGTA, PAF raised [Ca2+]i by 25 nM. This suggests that PAF causes influx of exogenous Ca2+, as well as releasing some Ca2+ from intracellular stores. Consistent with these results, when PAF was added to 1 mM Ca2+ in the presence of 100 microM Cd2+ or Mn2+ to block Ca2+ influx, [Ca2+]i increased by only intermediate amounts; at the times of such dampened peak response, [Ca2+]i could be raised within 1 min to normal PAF-stimulated levels by chelation of the exogenous heavy metals with diethylenetriaminepentaacetic acid. Normal PAF responses were observed in the presence of indomethacin. The lowest dose of PAF observed to raise [Ca2+]i was 0.1 ng/ml. Response of [Ca2+]i to 2-20 ng/ml PAF was transient, and second applications had no effect. The PAF response also was seen in

  19. Structures and biological activities of triterpenes and sesquiterpenes obtained from Russula lepida.

    PubMed

    Lee, Jong-Soo; Maarisit, Wilmar; Abdjul, Delfly B; Yamazaki, Hiroyuki; Takahashi, Ohgi; Kirikoshi, Ryota; Kanno, Syu-Ichi; Namikoshi, Michio

    2016-07-01

    A seco-cucurbitane triterpene and two aristolane sesquiterpenes, named (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid, (+)-1,2-didehydro-9-hydroxy-aristlone, and (+)-12-hydroxy-aristlone, were isolated from fruiting bodies of the medicinal mushroom Russula lepida, together with (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid and (+)-aristlone. The structures of the first three compounds, including their absolute configurations, were assigned on the basis of their NMR and ECD spectra. Two seco-cucurbitane triterpenes, (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid and (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid, inhibited the activity of protein tyrosine phosphatase 1B (PTP1B), with IC50 values of 20.3 and 0.4μM, respectively. All isolated compounds did not show cytotoxicity against human cancer cell lines, Huh-7 (hepatoma) and EJ-1 (bladder), at 50μM. PMID:27066716

  20. New electrochemical procedure for obtaining surface enhanced Raman scattering active polythiophene films on platinum

    NASA Astrophysics Data System (ADS)

    Bazzaoui, E. A.; Aeiyach, S.; Aubard, J.; Felidj, N.; Lévi, G.; Sakmeche, N.; Lacaze, P. C.

    1998-06-01

    A new electrochemical procedure for obtaining Surface Enhanced Raman Scattering (SERS) spectra of silver islands polybithiophene composite films is described. During the electropolymerization process which consists to use silver dodecylsulfate micellar aqueous solution mixed with bithiophene and LiClO4, silver cations are reduced, thus giving metallic silver particles embedded within the polybithiophene (PbT) film. Both doped and undoped PbT species display SERS spectra with exaltation factors varying between 40 and 200 with respect to the film prepared in sodium dodecylsulfate. Vibrational characterization of both doped and undoped species show that the amount of the polymer structural defects are more important in the oxidized species than in the reduced ones. This general method allows to synthesize various polymeric films displaying SERS effect and appears very promising for the structural study of these materials. Nous décrivons un procédé original pour synthétiser par voie électrochimique des films formés d'un composite de polybithiophène et d'îlots d'argent qui présentent des Spectres de Diffusion Raman Exaltée de Surface (DRES). Au cours de l'électropolymérisation d'une solution aqueuse micellaire de bithiophène en présence de dodécylsulfate d'argent (AgDS) et de LiClO4, les ions argent présents dans la solution se complexent avec le soufre du bithiophène et pénètrent dans le film polymère où ils sont réduits sous forme d'argent métallique. Les spectres Raman des deux formes réduite et oxydée du film ainsi obtenu présentent un effet DRES important avec un facteur d'exaltation variant entre 40 et 200 par rapport au même film électrosynthétisé en présence de dodécylsulfate de sodium (SDS). L'analyse vibrationnelle des deux formes redox montre que le taux de défauts est plus important dans la forme oxydée que dans la forme réduite. Cette méthode de polymérisation très générale, qui permet d'obtenir des polymères

  1. Nematicidal and antimicrobial activities of methanol extracts of 17 plants, of importance in ethnopharmacology, obtained from the Arabian Peninsula

    PubMed Central

    Al-Marby, Adel; Ejike, Chukwunonso ECC; Nasim, Muhammad Jawad; Awadh-Ali, Nasser A; Al-badani, Rwaida A; Alghamdi, Ghanem MA; Jacob, Claus

    2016-01-01

    Aim/Background: The development of resistance to synthetic drugs by target organisms is a major challenge facing medicine, yet locked within plants are phytochemicals used in herbal medicine (especially in the Arabian Peninsula) that may find application in this regard. In pursuit of unlocking these “hidden treasures,” the methanol extracts of leaves, aerial parts, fruits, and resins of 17 plants used in the Arabian Peninsula were screened for antimicrobial activities. Materials and Methods: The nematicidal, antibacterial, and antifungal activities were determined using appropriate assays. Steinernema feltiae, Staphylococcus carnosus, Escherichia coli, and Saccharomyces cerevisiae were used as test organisms. Concentrations of the extracts ranging from 0.5 to 20 mg/ml were tested and appropriate statistical tests performed on the data generated. Results: The results show that extracts from Solanum incanum, Chenopodium murale, Commiphora myrrha, Anthemis nobilis, and Achillea biebersteinii were the most active and had very high activities against two or more of the test organisms at low concentrations. Extracts of the leaves of S. incanum and resins of Ferula asafoetida were the most active nematicides, with significant activity at 0.5 mg/ml. Extracts of C. myrrha and C. murale had the most active antibacterial activity with inhibition zones of 12-15 mm and minimum inhibitory concentrations (MICs) of 2.5 mg/ml for both bacteria. Extracts of the leaves of A. biebersteinii were the most active fungicide, giving an MIC of 1.5 mg/ml. Conclusion: The results validate the use of these plants in ethnopharmacology, and open new vistas of opportunities for the development of cheap but effective agents that may be useful against infectious diseases. PMID:27104031

  2. Measuring internal energy deposition in collisional activation using hydrated ion nanocalorimetry to obtain peptide dissociation energies and entropies.

    PubMed

    Demireva, Maria; Williams, Evan R

    2010-07-01

    The internal energy deposited in both on- and off-resonance collisional activation in Fourier transform ion cyclotron resonance mass spectrometry is measured with ion nanocalorimetry and is used to obtain information about the dissociation energy and entropy of a protonated peptide. Activation of Na(+)(H(2)O)(30) results in sequential loss of water molecules, and the internal energy of the activated ion can be obtained from the abundances of the product ions. Information about internal energy deposition in on-resonance collisional activation of protonated peptides is inferred from dissociation data obtained under identical conditions for hydrated ions that have similar m/z and degrees-of-freedom. From experimental internal energy deposition curves and Rice-Ramsperger-Kassel-Marcus (RRKM) theory, dissociation data as a function of collision energy for protonated leucine enkephalin, which has a comparable m/z and degrees-of-freedom as Na(+)(H(2)O)(30), are modeled. The threshold dissociation energies and entropies are correlated for data acquired at a single time point, resulting in a relatively wide range of threshold dissociation energies (1.1 to 1.7 eV) that can fit these data. However, this range of values could be significantly reduced by fitting data acquired at different dissociation times. By measuring the internal energy of an activated ion, the number of fitting parameters necessary to obtain information about the dissociation parameters by modeling these data is reduced and could result in improved accuracy for such methods.

  3. Active tectonic deformation along rejuvenated faults in tropical Borneo: Inferences obtained from tectono-geomorphic evaluation

    NASA Astrophysics Data System (ADS)

    Mathew, Manoj Joseph; Menier, David; Siddiqui, Numair; Kumar, Shashi Gaurav; Authemayou, Christine

    2016-08-01

    active folding of the Rajang Group fold-thrust belt to present and these events reactivated old major faults and minor related dislocations. From geomorphic analysis associated with sedimentary record, we posit that the terrain could have undergone high uplift rates since 5 Ma or multi-phased uplift with periodic intermittent pulses of high and low uplift rates.

  4. Upgrading the rice husk char obtained by flash pyrolysis for the production of amorphous silica and high quality activated carbon.

    PubMed

    Alvarez, Jon; Lopez, Gartzen; Amutio, Maider; Bilbao, Javier; Olazar, Martin

    2014-10-01

    The overall valorization of rice husk char obtained by flash pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous flash pyrolysis in a conical spouted bed reactor at 500°C. Extraction with Na2CO3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800°C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365m(2)g(-1) at the end of 15min.

  5. Antimicrobial activity of clove oil dispersed in a concentrated sugar solution.

    PubMed

    Briozzo, J; Núñez, L; Chirife, J; Herszage, L; D'Aquino, M

    1989-01-01

    Essential oil of clove, dispersed (0.4% v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and Candida albicans. Staphylococcus aureus (five strains), Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens, and Escherichia coli inoculated at a level of 10(7) cfu/ml, and C. albicans (inoculum 4.0 x 10(5) cfu/ml) were killed (greater than 99.999%) after 2-7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4% (v/w) of essential oil of clove. Added organic matter (i.e. human or bovine serum) did not impair its antimicrobial activity. Sugar was not necessary for the antimicrobial activity of clove oil, but the concentrated sugar solution provided a good vehicle for obtaining an oil dispersion that is relatively stable for certain practical applications. PMID:2542213

  6. Active concentric ring electrode for non-invasive detection of intestinal myoelectric signals.

    PubMed

    Prats-Boluda, Gema; Garcia-Casado, Javier; Martinez-de-Juan, Jose L; Ye-Lin, Yiyao

    2011-05-01

    Although the surface electroenterogram (EEnG) is a weak signal contaminated by strong physiological interference, such as ECG and respiration, abdominal surface recordings of the EEnG could provide a non-invasive method of studying intestinal activity. The goal of this work was to develop a modular, active, low-cost and easy-to-use sensor to obtain a direct estimation of the Laplacian of the EEnG on the abdominal surface in order to enhance the quality of bipolar surface monitoring of intestinal activity. The sensor is made up of a set of 3 concentric dry Ag/AgCl ring electrodes and a battery-powered signal-conditioning circuit. Each section is etched on a different printed circuit board (PCB) and the sections are joined to each other by surface mount technology connectors. This means the sensing electrodes can be treated independently for purposes of maintenance and replacement and the signal conditioning circuit can be re-used. A total of ten recording sessions were carried out on humans. The results show that the surface recordings of the EEnG obtained by the active sensor present significantly less ECG and respiration interference than those obtained by bipolar recordings. In addition, bioelectrical sources whose frequency fitted with the slow wave component of the EEnG (SW) were identified by parametric spectral analysis in the surface signals picked up by the active sensors.

  7. In vitro activities of antimicrobial agents against clinical isolates of Flavimonas oryzihabitans obtained from patients with cancer.

    PubMed

    Rolston, K V; Ho, D H; LeBlanc, B; Bodey, G P

    1993-11-01

    We evaluated the in vitro activities of 21 different antimicrobial agents against nine clinical isolates of Flavimonas oryzihabitans obtained from patients with cancer. The organisms were susceptible to most agents commonly used for the empiric therapy (aminoglycosides, ureidopenicillins, extended-spectrum cephalosporins, monobactams, and carbapenems) and prevention of infections (quinolones and trimethoprim-sulfamethoxazole) in this patient population.

  8. In vitro activities of antimicrobial agents against clinical isolates of Flavimonas oryzihabitans obtained from patients with cancer.

    PubMed

    Rolston, K V; Ho, D H; LeBlanc, B; Bodey, G P

    1993-11-01

    We evaluated the in vitro activities of 21 different antimicrobial agents against nine clinical isolates of Flavimonas oryzihabitans obtained from patients with cancer. The organisms were susceptible to most agents commonly used for the empiric therapy (aminoglycosides, ureidopenicillins, extended-spectrum cephalosporins, monobactams, and carbapenems) and prevention of infections (quinolones and trimethoprim-sulfamethoxazole) in this patient population. PMID:8285645

  9. Post-glucose-load urinary C-peptide and glucose concentration obtained during OGTT do not affect oral minimal model-based plasma indices.

    PubMed

    Jainandunsing, Sjaam; Wattimena, J L Darcos; Rietveld, Trinet; van Miert, Joram N I; Sijbrands, Eric J G; de Rooij, Felix W M

    2016-05-01

    The purpose of this study was to investigate how renal loss of both C-peptide and glucose during oral glucose tolerance test (OGTT) relate to and affect plasma-derived oral minimal model (OMM) indices. All individuals were recruited during family screening between August 2007 and January 2011 and underwent a 3.5-h OGTT, collecting nine plasma samples and urine during OGTT. We obtained the following three subgroups: normoglycemic, at risk, and T2D. We recruited South Asian and Caucasian families, and we report separate analyses if differences occurred. Plasma glucose, insulin, and C-peptide concentrations were analyzed as AUCs during OGTT, OMM estimate of renal C-peptide secretion, and OMM beta-cell and insulin sensitivity indices were calculated to obtain disposition indices. Post-glucose load glucose and C-peptide in urine were measured and related to plasma-based indices. Urinary glucose corresponded well with plasma glucose AUC (Cau r = 0.64, P < 0.01; SA r = 0.69, P < 0.01), S I (Cau r = -0.51, P < 0.01; SA r = -0.41, P < 0.01), Φ dynamic (Cau r = -0.41, P < 0.01; SA r = -0.57, P < 0.01), and Φ oral (Cau r = -0.61, P < 0.01; SA r = -0.73, P < 0.01). Urinary C-peptide corresponded well to plasma C-peptide AUC (Cau r = 0.45, P < 0.01; SA r = 0.33, P < 0.05) and OMM estimate of renal C-peptide secretion (r = 0.42, P < 0.01). In general, glucose excretion plasma threshold for the presence of glucose in urine was ~10-10.5 mmol L(-1) in non-T2D individuals, but not measurable in T2D individuals. Renal glucose secretion during OGTT did not influence OMM indices in general nor in T2D patients (renal clearance range 0-2.1 %, with median 0.2 % of plasma glucose AUC). C-indices of urinary glucose to detect various stages of glucose intolerance were excellent (Cau 0.83-0.98; SA 0.75-0.89). The limited role of renal glucose secretion validates the neglecting of urinary glucose secretion in kinetic models of glucose homeostasis using plasma glucose concentrations. Both C

  10. Eplerenone mimics features of the alternative activation in macrophages obtained from patients with heart failure and healthy volunteers.

    PubMed

    Łabuzek, Krzysztof; Liber, Sebastian; Bułdak, Łukasz; Krupej-Kędzierska, Joanna; Machnik, Grzegorz; Bobrzyk, Magdalena; Okopień, Bogusław

    2014-03-01

    Alternative activation of macrophages plays protective role in cardiac remodelling in heart failure and the activity of mineralocorticoid receptor may determine the phenotype of these cells. We examined the influence of eplerenone, aldosterone, and IL-4 on descriptors of alternative activation in blood monocytes collected from 19 patients with heart-failure and 20 healthy volunteers. “Heart failure” macrophages in comparison with “healthy” macrophages had increased mineralocorticoid activity, NO and reactive oxygen species production, expression of iNOS mRNA and protein, but decreased expression of arginase I and mannose receptor proteins, and activity of MnSOD and CuZnSOD. Aldosterone increased mineralocorticoid activity, NO and reactive oxygen species production, iNOS mRNA and protein expression, MnSOD and CuZnSOD activity. Eplerenone attenuated the effects of aldosterone on all but MnSOD and CuZnSOD variables. Eplerenone alone increased the production of NO, MnSOD and CuZnSOD activity, arginase I gene and protein expression, and mannose receptor gene and protein expression, but decreased mineralocorticoid activity only in “heart failure” macrophages. The latter suggests altered function of mineralocorticoid receptor in heart failure. Increased mineralocorticoid activity accounts for increased NO production, iNOS gene and protein expression but does not explain the increased basal reactive oxygen species production and decreased markers of alternative activation in “heart failure” macrophages. In the lack of change in basal mineralocorticoid activity, eplerenone increases markers of alternative activation in a mineralocorticoid receptor-independent manner. Because of changes in iNOS and NO variable, eplerenone induced qualitatively different activation of macrophages from that obtained with IL-4.

  11. Active carbons obtained from bituminous coal for NO{sub 2} removal under dry and wet conditions at room temperature

    SciTech Connect

    Robert Pietrzak

    2009-07-15

    The adsorption of NO{sub 2} on active carbons obtained from Polish bituminous coal was studied. Carbonaceous adsorbents were obtained by pyrolysis of coal at 500, 600, and 700{sup o}C followed by activation with KOH at 700 {sup o}C. Adsorption of NO{sub 2} was carried out from dry and moist (70% humidity) air. The surface structure and chemistry of the initial and exhausted adsorbents were analyzed using adsorption of nitrogen, Boehm method, and elemental and thermal analyses. All adsorbents obtained were found to have acidic surfaces. The best NO{sub 2} sorption capacity in both dry and wet conditions was obtained for the active carbon pyrolyzed at 700{sup o}C, with respective values of 25.0 and 43.5 mg/g, respectively. For all materials a considerable amount of NO{sub 2} was reduced to NO. Differential thermogravimetry curves of samples after exposure to NO{sub 2} showed two new peaks, the first at 90-180{sup o}C, assigned to the removal of physically adsorbed NO{sub 2} and NO, and the second at 200-400{sup o}C, assigned to the decomposition of potassium nitrates and nitrites. 48 refs., 6 figs., 5 tabs.

  12. The relation of seismic activity and radon concentration

    SciTech Connect

    Kulali, Feride E-mail: iskender@fef.sdu.edu.tr; Akkurt, İskender E-mail: iskender@fef.sdu.edu.tr; Vogiannis, Efstratios

    2014-10-06

    Radon, which is the largest source of natural ionizing radiation, reaches to surface as gas or dissolved form in the ground water. Emanation of radon can has a profile is disposed to increasing or decreasing depending on the effects of meteorological events or crust movements. In this work, the radon concentration in soil gas, which is transported from soil to AlphaGUARD, is continuously measured in Mytilene (Greece). A graph of radon concentration is prepared for comparison with simultaneous earthquake data. As a consequence of comparison, we determined that the radon concentration indicates anomalies before the earthquakes.

  13. The relation of seismic activity and radon concentration

    NASA Astrophysics Data System (ADS)

    Kulali, Feride; Akkurt, Iskender; Vogiannis, Efstratios

    2014-10-01

    Radon, which is the largest source of natural ionizing radiation, reaches to surface as gas or dissolved form in the ground water. Emanation of radon can has a profile is disposed to increasing or decreasing depending on the effects of meteorological events or crust movements. In this work, the radon concentration in soil gas, which is transported from soil to AlphaGUARD, is continuously measured in Mytilene (Greece). A graph of radon concentration is prepared for comparison with simultaneous earthquake data. As a consequence of comparison, we determined that the radon concentration indicates anomalies before the earthquakes.

  14. Ex vivo digestion of carp muscle tissue--ACE inhibitory and antioxidant activities of the obtained hydrolysates.

    PubMed

    Borawska, J; Darewicz, M; Vegarud, G E; Iwaniak, A; Minkiewicz, P

    2015-01-01

    In the digestive tract of humans, bioactive peptides, i.e. protein fragments impacting the physiological activity of the body, may be released during the digestion of food proteins, including those of fish. The aim of the study was to establish the method of human ex vivo digestion of carp muscle tissue and evaluate the angiotensin I-converting enzyme inhibitory and antioxidant activities of hydrolysates obtained after digestion. It was found that the hydrolysates of carp muscle tissue obtained with the three-stage method of simulated ex vivo digestion showed ACE inhibitory as well as antioxidative activities. It was demonstrated that the degree of hydrolysis depended on the duration of individual stages and the degree of comminution of the examined material. Although the applied gastric juices initiated the process of hydrolysis of carp muscle tissue, the duodenal juices caused a rapid increase in the amount of hydrolysed polypeptide bonds. The antihypertensive and antioxidative activities of the hydrolysates of carp muscle tissue increased together with progressive protein degradation. However, the high degree of protein hydrolysis does not favour an increase in the activity of free radical scavenging. The presented results are an example of the first preliminary screening of the potential health-promoting biological activity of carp muscle tissue in an ex vivo study.

  15. Glutathione peroxidase activity, selenium, and lipid peroxide concentrations in blood from a healthy Polish population : I. Maternal and cord blood.

    PubMed

    Zachara, B A; Wąsowicz, W; Gromadzińska, J; Skłodowska, M; Krasomski, G

    1986-09-01

    Selenium (Se) concentrations in whole blood and plasma of 19 nonpregnant women. 14 mothers at delivery, 14 neonates, and 13 infants, aged 2-12 mo, were evaluated. The activity of glutathione peroxidase (GSH-Px) in erythrocytes and plasma and the level of lipid peroxides in plasma were also analyzed. Selenium concentrations in whole blood and plasma in mothers at delivery were significantly lower compared to nonpregnant women. Selenium concentrations in cord blood components were lower compared to mothers, but the differences were not significant. The concentration of the element decreased in the first few months of life. Glutathione peroxidase activity in erythrocytes differed only slightly in the examined groups. In plasma, however, the enzyme activity was significantly lower in pregnant compared to nonpregnant women and in neonates compared to their mothers. Lipid peroxide concentrations in plasma differed only slightly in the examined groups. The results obtained are discussed in terms of the observations of other investigators. PMID:24254392

  16. Toxic Metal Concentrations in Cigarettes Obtained from U.S. Smokers in 2009: Results from the International Tobacco Control (ITC) United States Survey Cohort

    PubMed Central

    Caruso, Rosalie V.; O’Connor, Richard J.; Stephens, W. Edryd; Cummings, K. Michael; Fong, Geoffrey T.

    2013-01-01

    Smoking-related diseases can be attributed to the inhalation of many different toxins, including heavy metals, which have a host of detrimental health effects. The current study reports the levels of arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb) in cigarettes obtained from adult smokers participating in the 2009 wave of the ITC United States Survey (N = 320). The mean As, Cd, Cr, Ni, and Pb levels were 0.17, 0.86, 2.35, 2.21, and 0.44 µg/g, respectively. There were some differences in metal concentrations of cigarette brands produced by different manufacturers, suggesting differences in the source of tobaccos used by different companies. For Ni, there were significant pairwise differences between Philip Morris U.S. (PMUSA) and R.J. Reynolds (RJR) brands (PMUSA higher; p < 0.001), PMUSA and other manufacturer (OM) brands (PMUSA higher; p < 0.001), and RJR and OM brands (RJR higher; p = 0.006). For Cr, RJR brands had higher levels than did OM brands (p = 0.02). Levels of As, Cd, and Pb did not differ significantly across manufacturer groups (p > 0.10). Because of the variety of toxic heavy metals in cigarette tobacco, and their numerous negative health effects, metal content in cigarette tobacco should be reduced. PMID:24452255

  17. Toxic metal concentrations in cigarettes obtained from U.S. smokers in 2009: results from the International Tobacco Control (ITC) United States survey cohort.

    PubMed

    Caruso, Rosalie V; O'Connor, Richard J; Stephens, W Edryd; Cummings, K Michael; Fong, Geoffrey T

    2013-12-20

    Smoking-related diseases can be attributed to the inhalation of many different toxins, including heavy metals, which have a host of detrimental health effects. The current study reports the levels of arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb) in cigarettes obtained from adult smokers participating in the 2009 wave of the ITC United States Survey (N = 320). The mean As, Cd, Cr, Ni, and Pb levels were 0.17, 0.86, 2.35, 2.21, and 0.44 µg/g, respectively. There were some differences in metal concentrations of cigarette brands produced by different manufacturers, suggesting differences in the source of tobaccos used by different companies. For Ni, there were significant pairwise differences between Philip Morris U.S. (PMUSA) and R.J. Reynolds (RJR) brands (PMUSA higher; p < 0.001), PMUSA and other manufacturer (OM) brands (PMUSA higher; p < 0.001), and RJR and OM brands (RJR higher; p = 0.006). For Cr, RJR brands had higher levels than did OM brands (p = 0.02). Levels of As, Cd, and Pb did not differ significantly across manufacturer groups (p > 0.10). Because of the variety of toxic heavy metals in cigarette tobacco, and their numerous negative health effects, metal content in cigarette tobacco should be reduced.

  18. Antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) by using different extraction methods.

    PubMed

    Karakaya, Sibel; El, Sedef Nehir; Karagözlü, Nural; Sahin, Serpil

    2011-06-01

    In this study, antioxidant and antimicrobial activities of essential oils obtained from oregano (Origanum vulgare ssp. hirtum) were determined by using solvent-free microwave extraction (SFME), supercritical fluid extraction, and conventional hydrodistillation (CH) methods. The inhibitory effects on the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical of essential oils obtained from oregano by using SFME and CH were similar. However, essential oil extracted by CH showed greater (2.69 μmol/μL of oil) Trolox equivalent antioxidant capacity (TEAC) than oregano oils obtained by SFME (P < .05). The difference between percentage inhibition and TEAC values most probably is due to the fact that undiluted and diluted samples are used in the percentage inhibition assay and the TEAC assay, respectively. TEAC values of oregano essential oils obtained by SFME at different microwave power levels were found to be similar and ranged from 0.72 to 0.84 μmol/μL of oil. Essential oils obtained by CH and SFME at different microwave powers inhibited the survival of Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7, whereas survival of Staphylococcus aureus was not influenced. In addition, oregano oil obtained by SFME at 40% power level did not show any inhibitory effect on E. coli O157:H7.

  19. Using Photon Activation Analysis To Determine Concentrations Of Unknown Components In Reference Materials

    SciTech Connect

    Green, Jaromy; Sun, Zaijing; Wells, Doug; Maschner, Herb

    2011-06-01

    Using certified multi-element reference materials for instrumental analyses one frequently is confronted with the embarrassing fact that the concentration of some desired elements are not given in the respective certificate, nonetheless are detectable, e.g. by photon activation analysis (PAA). However, these elements might be determinable with sufficient quality of the results using scaling parameters and the well-known quantities of a reference element within the reference material itself. Scaling parameters include: activation threshold energy, Giant Dipole Resonance (GDR) peak and endpoint energy of the bremsstrahlung continuum; integrated photo-nuclear cross sections for the isotopes of the reference element; bremsstrahlung continuum integral; target thickness; photon flux density. Photo-nuclear cross sections from the unreferenced elements must be known, too. With these quantities, the integral was obtained for both the known and unknown elements resulting in an inference of the concentration of the unreported element based upon the reported value, thus also the concentration of the unreferenced element in the reference material. A similar method to determine elements using the basic nuclear and experimental data has been developed for thermal neutron activation analysis some time ago (k{sub 0} Method).

  20. Antiproliferative activity of flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the MCF7, KB, and NIH/3T3 cell lines.

    PubMed

    Nedel, Fernanda; Begnini, Karine; Carvalho, Pedro Henrique de Azambuja; Lund, Rafael Guerra; Beira, Fátima T A; Del Pino, Francisco Augusto B

    2012-11-01

    This study assessed the antiproliferative effect in vitro of the flower hexane extract obtained from Mentha spicata associated with Mentha rotundifolia against the human breast adenocarcinoma (MCF-7), human mouth epidermal carcinoma (KB), and mouse embryonic fibroblast (NIH 3T3) cell lines, using sulforhodamine B (SRB) assay. A cell density of 2×10(4)/well was seeded in 96-well plates, and samples at different concentrations ranging from 10 to 500 mg/mL were tested. The optical density was determined in an ELISA multiplate reader (Thermo Plate TP-Reader). Results demonstrated that the hexane extract presented antiproliferative activity against both the tumor cell lines KB and MCF-7, presenting a GI(50) (MCF-7=13.09 mg/mL), TGI (KB=37.76 mg/mL), and IL(50) (KB=291.07 mg/mL). Also, the hexane extract presented antiproliferative activity toward NIH 3T3 cells GI(50) (183.65 mg/mL), TGI (280.54 mg/mL), and IL(50) (384.59 mg/mL). The results indicate that the flower hexane extract obtained from M. spicata associated with M. rotundifolia presents an antineoplastic activity against KB and MCF-7, although an antiproliferative effect at a high concentration of the extract was observed toward NIH 3T3.

  1. Effects of Manisa propolis on telomerase activity in leukemia cells obtained from the bone marrow of leukemia patients.

    PubMed

    Cogulu, O; Biray, C; Gunduz, C; Karaca, E; Aksoylar, S; Sorkun, K; Salih, B; Ozkinay, F

    2009-11-01

    Propolis is a resinous material collected by honeybees and obtained from beehives that has anticancer effects by inducing apoptosis. The aim of this study is to investigate the effect of propolis on human telomerase reverse transcriptase (hTERT) in the leukemia cells obtained from leukemia patients. Four different bone marrow cell cultures from each of four leukemia cases were prepared. The 60 ng/ml, 30 ng/ml and 15 ng/ml working concentrations of propolis were administered to three cultures of each patient, while one culture contained only culture medium. hTERT mRNA expression levels of cells were detected at 24 h, 48 h and 72 h using the LightCycler 2.0 instrument. A significant decrease in hTERT expression levels was observed in the 60 ng/ml concentration of propolis. In conclusion, Manisa propolis may also have a potential effect on the expression of hTERT in leukemia-particularly owing to its constituent chrysin.

  2. Chemical Composition and Biological Activity of Extracts Obtained by Supercritical Extraction and Ethanolic Extraction of Brown, Green and Red Propolis Derived from Different Geographic Regions in Brazil.

    PubMed

    Machado, Bruna Aparecida Souza; Silva, Rejane Pina Dantas; Barreto, Gabriele de Abreu; Costa, Samantha Serra; Silva, Danielle Figuerêdo da; Brandão, Hugo Neves; Rocha, José Luiz Carneiro da; Dellagostin, Odir Antônio; Henriques, João Antônio Pegas; Umsza-Guez, Marcelo Andres; Padilha, Francine Ferreira

    2016-01-01

    The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection.

  3. Chemical Composition and Biological Activity of Extracts Obtained by Supercritical Extraction and Ethanolic Extraction of Brown, Green and Red Propolis Derived from Different Geographic Regions in Brazil

    PubMed Central

    Machado, Bruna Aparecida Souza; Silva, Rejane Pina Dantas; Barreto, Gabriele de Abreu; Costa, Samantha Serra; da Silva, Danielle Figuerêdo; Brandão, Hugo Neves; da Rocha, José Luiz Carneiro; Dellagostin, Odir Antônio; Henriques, João Antônio Pegas; Umsza-Guez, Marcelo Andres; Padilha, Francine Ferreira

    2016-01-01

    The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection. PMID:26745799

  4. Concentration dependent differential activity of signalling molecules in Caenorhabditis elegans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Caenorhabditis elegans employs specific glycosides of the dideoxysugar ascarylose (the ‘ascarosides’) for monitoring population density/ dauer formation and finding mates. A synergistic blend of three ascarosides, called ascr#2, ascr#3 and ascr#4 acts as a dauer pheromone at a high concentration na...

  5. Three-Dimensional Concentration Measurements around Actively Tracking Blue Crabs

    NASA Astrophysics Data System (ADS)

    Dickman, B. D.; Jackson, J. L.; Weissburg, M. J.; Webster, D. R.

    2006-11-01

    Many aquatic arthropods locate food, suitable habitats, and mates solely through information extracted by chemical signals in their environment. Chemical plumes detected by larger animals are influenced by turbulence that creates an intermittent and unpredictable chemical stimulus environment. To link the stimulus pattern to behavior, we have developed a measurement system to quantify the instantaneous odor concentration surrounding a freely tracking blue crab through three-dimensional laser-induced fluorescence (3DLIF). A blue crab receives chemical stimulus at several locations, including the antennules near the mouth region and the distal tips of the legs and claws. Hence, three-dimensional measurements of the concentration field are required to link behavior to plume structure. During trials, crabs began their search 150 cm downstream of a source, and walking kinematics were recording simultaneously. The crabs were reversibly ``blindfolded'' during tracking to prevent aversive reactions to the intense laser light. Our experiments allow us to examine how hypothesized navigational cues, such as concentration bursts at the antennules and spatial asymmetry in concentration at the distributed chemosensory organs on the legs and claws, results in particular decisions during navigation.

  6. High antioxidant activity of coffee silverskin extracts obtained by the treatment of coffee silverskin with subcritical water.

    PubMed

    Narita, Yusaku; Inouye, Kuniyo

    2012-12-01

    Coffee silverskin (CS) is a thin tegument of the outer layer of green coffee beans and a major by-product of the roasting process to produce roasted coffee beans. CS extracts obtained by the treatment of CS with subcritical water at 25-270°C were investigated for their antioxidant activity using hydrophilic oxygen radical absorption capacity (H-ORAC) and DPPH radical scavenging capacity assays. The antioxidant activity increased with increasing the extraction temperature and the highest activity was observed with the extracts obtained at 270°C. The H-ORAC and DPPH values of the extracts were 2629±193 and 379±36μmol TE/g of CS extract, respectively. High correlation (R=0.999) was observed between H-ORAC and DPPH values for the CS extracts. High correlation of the antioxidant activity was also observed with protein and phenolic contents in the extracts. The CS extracts could be useful as a good source of antioxidative materials.

  7. In vitro antifungal activity of extracts obtained from Hypericum perforatum adventitious roots cultured in a mist bioreactor against planktonic cells and biofilm of Malassezia furfur.

    PubMed

    Simonetti, Giovanna; Tocci, Noemi; Valletta, Alessio; Brasili, Elisa; D'Auria, Felicia Diodata; Idoux, Alicia; Pasqua, Gabriella

    2016-01-01

    Xanthone-rich extracts from Hypericum perforatum root cultures grown in a Mist Bioreactor as antifungal agents against Malassezia furfur. Extracts of Hypericum perforatum roots grown in a bioreactor showed activity against planktonic cells and biofilm of Malassezia furfur. Dried biomass, obtained from roots grown under controlled conditions in a ROOTec mist bioreactor, has been extracted with solvents of increasing polarity (i.e. chloroform, ethyl acetate and methanol). The methanolic fraction was the richest in xanthones (2.86 ± 0.43 mg g(-1) DW) as revealed by HPLC. The minimal inhibitory concentration of the methanol extract against M. furfur planktonic cells was 16 μg mL(-1). The inhibition percentage of biofilm formation, at a concentration of 16 μg mL(-1), ranged from 14% to 39%. The results show that H. perforatum root extracts could be used as new antifungal agents in the treatment of Malassezia infections.

  8. Adsorption and structural properties of soft-templated mesoporous carbons obtained by carbonization at different temperatures and KOH activation

    NASA Astrophysics Data System (ADS)

    Górka, Joanna; Zawislak, Aleksandra; Choma, Jerzy; Jaroniec, Mietek

    2010-06-01

    Two series of phenolic resin-based mesoporous carbons were prepared by soft-templating strategy, which involves the formation of thermosetting carbon precursor by polymerization of phloroglucinol and formaldehyde in hydrophilic mesodomains of a thermally decomposable triblock copolymer used as a soft-template. It was shown that the volumes of mesopores and micropores in the resulting carbons can be tuned by varying carbonization temperature of phenolic resins in the range from 400 to 1000 °C followed by the post-synthesis KOH activation at 700 °C. The highly microporous carbons were obtained by KOH activation of phenolic resins pyrolyzed at lower temperature (˜500 °C), while high temperature KOH activation (˜800 °C) afforded microporous carbons with preserved mesoporosity.

  9. Variability in Saponin Content, Cancer Antiproliferative Activity and Physicochemical Properties of Concentrated Agave Sap.

    PubMed

    Santos-Zea, Liliana; Rosas-Pérez, Aratza Mireya; Leal-Díaz, Ana María; Gutiérrez-Uribe, Janet A

    2016-08-01

    Concentrated agave sap (CAS) has gained popularity as an unrefined sweetener. It is obtained by boiling "aguamiel" that contains phytochemicals with diverse bioactivities. Saponins have been the most widely studied agave phytochemicals due to their cancer antiproliferative effect but their concentration may vary due to maturity of the agave plant and collection site. In this study, 18 CAS samples produced in different states of Mexico were analyzed using multivariate methods to determine which physicochemical or phytochemical parameters were responsible for variation. Additionally, extracts with different saponin profiles were tested to determine possible correlations with antiproliferative activity. Total soluble solids, pH, and water activity were similar to those reported for other agave sweeteners. Antioxidant capacity of samples was correlated to browning index. Eleven steroidal saponins were found in CAS samples and they were the main source of variability. Magueyoside B, a kammogenin tetraglycoside, was the most abundant saponin in all samples. With respect to bioactivity, multivariate analysis indicated that magueyoside B and a gentrogenin tetraglycoside were compounds strongly related with bioactivity. CAS from Hidalgo, Puebla, and Veracruz had higher concentration of magueyoside B than from the other kamogenin tetraglycoside found in the samples from other Mexican states. These results could be used as a first approach to characterize and standardize CAS to validate the potential health benefits derived from its consumption. PMID:27376349

  10. Variability in Saponin Content, Cancer Antiproliferative Activity and Physicochemical Properties of Concentrated Agave Sap.

    PubMed

    Santos-Zea, Liliana; Rosas-Pérez, Aratza Mireya; Leal-Díaz, Ana María; Gutiérrez-Uribe, Janet A

    2016-08-01

    Concentrated agave sap (CAS) has gained popularity as an unrefined sweetener. It is obtained by boiling "aguamiel" that contains phytochemicals with diverse bioactivities. Saponins have been the most widely studied agave phytochemicals due to their cancer antiproliferative effect but their concentration may vary due to maturity of the agave plant and collection site. In this study, 18 CAS samples produced in different states of Mexico were analyzed using multivariate methods to determine which physicochemical or phytochemical parameters were responsible for variation. Additionally, extracts with different saponin profiles were tested to determine possible correlations with antiproliferative activity. Total soluble solids, pH, and water activity were similar to those reported for other agave sweeteners. Antioxidant capacity of samples was correlated to browning index. Eleven steroidal saponins were found in CAS samples and they were the main source of variability. Magueyoside B, a kammogenin tetraglycoside, was the most abundant saponin in all samples. With respect to bioactivity, multivariate analysis indicated that magueyoside B and a gentrogenin tetraglycoside were compounds strongly related with bioactivity. CAS from Hidalgo, Puebla, and Veracruz had higher concentration of magueyoside B than from the other kamogenin tetraglycoside found in the samples from other Mexican states. These results could be used as a first approach to characterize and standardize CAS to validate the potential health benefits derived from its consumption.

  11. The effects of cerium doping concentration on the properties and photocatalytic activity of bimetallic Mo/Ce catalyst

    NASA Astrophysics Data System (ADS)

    Allaedini, Ghazaleh; Tasirin, Siti Masrinda; Aminayi, Payam

    2016-10-01

    In this study, the characterization and photocatalytic activity of MoO3 nanoparticles doped with various doping concentrations of cerium have been investigated. The Fourier transform infrared (FT-IR) spectra of the prepared catalysts confirmed that MoO3 particles have been successfully doped by cerium. Field emission scanning electron microscopy (FESEM) was performed to visualize the surface morphology of the obtained catalysts. The XRD patterns suggested that the crystallinity of the sample with the lowest doping concentration of 15 mol % was higher in comparison with samples of higher doping concentrations. The volume-averaged crystal sizes of the obtained catalysts were calculated to be 25, 28, and 32 nm for 15, 35, and 60 mol % samples, respectively. The photocatalytic activity along with the reaction kinetics of Ce-doped MoO3 nanoparticles have also been investigated through the dye degradation of methyl orange. The synthesized Ce-doped MoO3 particles with the lowest dopant concentration of 15 mol % exhibited the highest photocatalytic activity for methyl orange dye degradation. It was observed that photo-degradation activity decreased with an increase in the doping concentration of cerium. The predicted rate constants for samples with 15, 35, and 60 mol % doping concentrations were found to be 0.0432, 0.035, and 0.029 min-1, respectively.

  12. Sulphated modification of a polysaccharide obtained from fresh persimmon (Diospyros kaki L.) fruit and antioxidant activities of the sulphated derivatives.

    PubMed

    Zhang, Yali; Lu, Xiaoyun; Fu, Zhongbin; Wang, Zibao; Zhang, Jianbao

    2011-08-01

    Free radicals and other reactive oxygen species (ROS) are believed to play significant roles in ageing as well as in a number of degenerative or pathological diseases. This paper reports the preparation, characterisation and potential antioxidant activity of a type of chemically sulphated polysaccharide isolated from fresh persimmon (Diospyros kaki L.) fruit. Three sulphated derivatives with variable degrees of substitution (0.8, 1.7 and 2.5) were obtained by the chlorosulphonic acid-pyridine method. The sulphated derivatives all showed dose-dependent reducing power and free radical scavenging effect of 1,1-dipheny-l-2-picrylhydrazyl, superoxide anion and hydroxyl. Our results showed that the sulphated modification of polysaccharides significantly increased their antioxidant activities and may be an effective way to prepare these valuable derivatives.

  13. Mutagenicity studies in a tyre plant: in vitro activity of workers' urinary concentrates and raw materials.

    PubMed

    Crebelli, R; Paoletti, A; Falcone, E; Aquilina, G; Fabri, G; Carere, A

    1985-07-01

    The possible contribution to urinary mutagenicity of occupational exposures in the rubber industry was studied by assaying the urine concentrates of 72 workmen (44 smokers) employed in a tyre plant. Twenty three clerks (16 smokers) engaged in the administrative department of the same factory served as presumptive unexposed controls. XAD-2 resin concentrates of urine samples were assayed in the plate incorporation test and in the microtitre fluctuation assay with Salmonella typhimurium strains TA1535, TA98, and TA100. Furthermore, the in vitro mutagenicity of the major raw materials in use at the plant was determined in the plate incorporation assay with S typhimurium strains TA1535, TA1537, TA98, and TA100. The results obtained from the urinary mutagenicity study show that smoking habits, but not occupation, were statistically significantly related to the appearance of a urinary mutagenicity that was detectable with strain TA98. A possible synergistic effect of occupation with smoking was observed among tyre builders who were also smokers. The study of the raw materials showed that three technical grade materials were weakly active as mutagens in strain TA98 in the absence (poly-p-dinitrosobenzene) or in the presence of metabolic activation (mixed diaryl-p-phenylendiamines and tetramethyltiuram disulphide). The latter chemical was also weakly active in strain TA100. PMID:4015996

  14. Russian Activities in Space Photovoltaic Power Modules with Concentrators

    NASA Technical Reports Server (NTRS)

    Andreev, Vyacheslav M.; Rumyantsev, Valeri D.

    2004-01-01

    Space concentrator modules with point-and line-focus Fresnel lenses and with reflective parabolic troughs have been developed recently at Ioffe Physico-Technical Institute. PV receivers for these modules are based: on the single junction LPE and MOCVD AlGaAs/GaAs solar cells characterized by AM0 efficiencies of 23.5 - 24% at 20 - 50 suns and 24 - 24.75 at 50 - 200 suns; on the mechanically stacked tandem AlGaAs/GaAs-GaSb cells with efficiency of 27 - 28 at 20 - 100 suns. MOCVD AlGaAs/GaAs cells with internal Bragg reflector have shown a higher radiation resistance as compared to a traditional structure. Monolithic two-terminal tandems AlGaAs (top)-GaAs (bottom) for space application and GaSb (top) - InGaAsSb (bottom) for TRV application are under development as well.

  15. Structure and antioxidant activity of soy protein isolate-dextran conjugates obtained by TiO2 photocatalysis.

    PubMed

    Jin, Bei; Zhou, Xiaosong; Li, Bing; Chen, Caiyan; Zhang, Xiaosa; Chen, Siqiao

    2015-01-01

    The aim of this study was to investigate the structural characteristics and antioxidant activities of soy protein isolate- (SPI-) dextran conjugates obtained by TiO2 photocatalysis treatment. Results revealed that the UV-vis absorption and the fluorescence intensity increased as the photocatalytic power increased (P < 0.05). Higher photocatalytic power could promote the extent of glycation and the formation of high molecular weight SPI-dextran conjugates, which were evidenced by free amino group content and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The Fourier transform infrared (FT-IR) spectra suggested that the amide I, II, and III bands of SPI were altered by the glycation induced by TiO2 photocatalysis. Moreover, significant changes of secondary structure occurred in SPI-dextran conjugates. The α-helix, β-sheet, β-turns, and random coil were changed from approximately 10.6%, 37.9%, 12.9%, and 38.6% to 3.8%, 10.4%, 17.7%, and 68.8%, respectively, after treatment at photocatalytic power of 1000 W. In addition, SPI-dextran conjugates obtained by TiO2 photocatalysis treatment exhibited high hydroxyl radical scavenging activity and possessed increased reducing power. All data indicated that TiO2 photocatalysis was an efficient method for promoting protein-polysaccharide copolymerisation.

  16. Structure and antioxidant activity of soy protein isolate-dextran conjugates obtained by TiO2 photocatalysis.

    PubMed

    Jin, Bei; Zhou, Xiaosong; Li, Bing; Chen, Caiyan; Zhang, Xiaosa; Chen, Siqiao

    2015-01-01

    The aim of this study was to investigate the structural characteristics and antioxidant activities of soy protein isolate- (SPI-) dextran conjugates obtained by TiO2 photocatalysis treatment. Results revealed that the UV-vis absorption and the fluorescence intensity increased as the photocatalytic power increased (P < 0.05). Higher photocatalytic power could promote the extent of glycation and the formation of high molecular weight SPI-dextran conjugates, which were evidenced by free amino group content and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The Fourier transform infrared (FT-IR) spectra suggested that the amide I, II, and III bands of SPI were altered by the glycation induced by TiO2 photocatalysis. Moreover, significant changes of secondary structure occurred in SPI-dextran conjugates. The α-helix, β-sheet, β-turns, and random coil were changed from approximately 10.6%, 37.9%, 12.9%, and 38.6% to 3.8%, 10.4%, 17.7%, and 68.8%, respectively, after treatment at photocatalytic power of 1000 W. In addition, SPI-dextran conjugates obtained by TiO2 photocatalysis treatment exhibited high hydroxyl radical scavenging activity and possessed increased reducing power. All data indicated that TiO2 photocatalysis was an efficient method for promoting protein-polysaccharide copolymerisation. PMID:26495283

  17. Structure and Antioxidant Activity of Soy Protein Isolate-Dextran Conjugates Obtained by TiO2 Photocatalysis

    PubMed Central

    Jin, Bei; Zhou, Xiaosong; Li, Bing; Chen, Caiyan; Zhang, Xiaosa; Chen, Siqiao

    2015-01-01

    The aim of this study was to investigate the structural characteristics and antioxidant activities of soy protein isolate- (SPI-) dextran conjugates obtained by TiO2 photocatalysis treatment. Results revealed that the UV-vis absorption and the fluorescence intensity increased as the photocatalytic power increased (P < 0.05). Higher photocatalytic power could promote the extent of glycation and the formation of high molecular weight SPI-dextran conjugates, which were evidenced by free amino group content and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The Fourier transform infrared (FT-IR) spectra suggested that the amide I, II, and III bands of SPI were altered by the glycation induced by TiO2 photocatalysis. Moreover, significant changes of secondary structure occurred in SPI-dextran conjugates. The α-helix, β-sheet, β-turns, and random coil were changed from approximately 10.6%, 37.9%, 12.9%, and 38.6% to 3.8%, 10.4%, 17.7%, and 68.8%, respectively, after treatment at photocatalytic power of 1000 W. In addition, SPI-dextran conjugates obtained by TiO2 photocatalysis treatment exhibited high hydroxyl radical scavenging activity and possessed increased reducing power. All data indicated that TiO2 photocatalysis was an efficient method for promoting protein-polysaccharide copolymerisation. PMID:26495283

  18. Structural Characterization and Antimicrobial Activity of a Biosurfactant Obtained From Bacillus pumilus DSVP18 Grown on Potato Peels

    PubMed Central

    Sharma, Deepak; Ansari, Mohammad Javed; Gupta, Sonam; Al Ghamdi, Ahmad; Pruthi, Parul; Pruthi, Vikas

    2015-01-01

    Background: Biosurfactants constitute a structurally diverse group of surface-active compounds derived from microorganisms. They are widely used industrially in various industrial applications such as pharmaceutical and environmental sectors. Major limiting factor in biosurfactant production is their production cost. Objectives: The aim of this study was to investigate biosurfactant production under laboratory conditions with potato peels as the sole source of carbon source. Materials and Methods: A biosurfactant-producing bacterial strain (Bacillus pumilus DSVP18, NCBI GenBank accession no. GQ865643) was isolated from motor oil contaminated soil samples. Biochemical characteristics of the purified biosurfactant were determined and its chemical structure was analyzed. Stability studies were performed and biological activity of the biosurfactant was also evaluated. Results: The strain, when grown on modified minimal salt media supplemented with 2% potato peels as the sole carbon source, showed the ability to reduce Surface Tension (ST) value of the medium from 72 to 28.7 mN/m. The isolated biosurfactant (3.2 ± 0.32 g/L) was stable over a wide range of temperatures (20 - 120 ºC), pH (2-12) and salt concentrations (2 - 12%). When characterized using high-performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy, it was found to be a lipopeptide in nature, which was further confirmed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (mass peak 1044.60) and nuclear magnetic resonance (NMR) studies. Data showed that the isolated biosurfactant at the concentration range of 30 - 35 µg/ml had strong antimicrobial activity when tested against standard strains of Bacillus cereus, Escherichia coli, Salmonella enteritidis, Staphylococcus aureus and Paenibacillus larvae. Conclusions: Potato peels were proved to be potentially useful substrates for biosurfactant production by B. pumilus DSVP18. The strain possessed a

  19. Composition, in vitro antioxidant and antimicrobial activities of essential oil and oleoresins obtained from black cumin seeds (Nigella sativa L.).

    PubMed

    Singh, Sunita; Das, S S; Singh, G; Schuff, Carola; de Lampasona, Marina P; Catalán, César A N

    2014-01-01

    Gas chromatography-mass spectrometry (GC-MS) analysis revealed the major components in black cumin essential oils which were thymoquinone (37.6%) followed by p-cymene (31.2%), α-thujene (5.6%), thymohydroquinone (3.4%), and longifolene (2.0%), whereas the oleoresins extracted in different solvents contain linoleic acid as a major component. The antioxidant activity of essential oil and oleoresins was evaluated against linseed oil system at 200 ppm concentration by peroxide value, thiobarbituric acid value, ferric thiocyanate, ferrous ion chelating activity, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging methods. The essential oil and ethyl acetate oleoresin were found to be better than synthetic antioxidants. The total phenol contents (gallic acid equivalents, mg GAE per g) in black cumin essential oil, ethyl acetate, ethanol, and n-hexane oleoresins were calculated as 11.47 ± 0.05, 10.88 ± 0.9, 9.68 ± 0.06, and 8.33 ± 0.01, respectively, by Folin-Ciocalteau method. The essential oil showed up to 90% zone inhibition against Fusarium moniliforme in inverted petri plate method. Using agar well diffusion method for evaluating antibacterial activity, the essential oil was found to be highly effective against Gram-positive bacteria.

  20. Composition, In Vitro Antioxidant and Antimicrobial Activities of Essential Oil and Oleoresins Obtained from Black Cumin Seeds (Nigella sativa L.)

    PubMed Central

    Singh, Sunita; Das, S. S.; Singh, G.; Schuff, Carola; de Lampasona, Marina P.; Catalán, César A. N.

    2014-01-01

    Gas chromatography-mass spectrometry (GC-MS) analysis revealed the major components in black cumin essential oils which were thymoquinone (37.6%) followed by p-cymene (31.2%), α-thujene (5.6%), thymohydroquinone (3.4%), and longifolene (2.0%), whereas the oleoresins extracted in different solvents contain linoleic acid as a major component. The antioxidant activity of essential oil and oleoresins was evaluated against linseed oil system at 200 ppm concentration by peroxide value, thiobarbituric acid value, ferric thiocyanate, ferrous ion chelating activity, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging methods. The essential oil and ethyl acetate oleoresin were found to be better than synthetic antioxidants. The total phenol contents (gallic acid equivalents, mg GAE per g) in black cumin essential oil, ethyl acetate, ethanol, and n-hexane oleoresins were calculated as 11.47 ± 0.05, 10.88 ± 0.9, 9.68 ± 0.06, and 8.33 ± 0.01, respectively, by Folin-Ciocalteau method. The essential oil showed up to 90% zone inhibition against Fusarium moniliforme in inverted petri plate method. Using agar well diffusion method for evaluating antibacterial activity, the essential oil was found to be highly effective against Gram-positive bacteria. PMID:24689064

  1. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV.

  2. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. PMID:26773821

  3. Determination of lead(II) sorption capacity of hazelnut shell and activated carbon obtained from hazelnut shell activated with ZnCl2.

    PubMed

    Şencan, Aziz; Karaboyacı, Mustafa; Kılıç, Mehmet

    2015-03-01

    This study aimed to determine the Pb(+2) adsorption capacities of hazelnut shell and activated carbon obtained from hazelnut shell. It also aimed to determine the effect of ZnCl2 in the activation process. The hazelnut was pyrolyzed at 250 and 700 °C. For determining the capture speed of the adsorbents, the pseudo-first- and second-order kinetic studies were performed. The Freundlich and Langmuir isotherm models were used to determine adsorption equilibrium. The surface characterization of hazelnut shell and activated carbon was determined by Brunauer-Emmett-Teller (BET) analysis and FTIR spectrum. Pb(+2) adsorption capacity of obtaining activated carbon was determined by ICP-OES analysis. The raw hazelnut shell's BET surface area is 5.92 m(2)/g and the surface area of activated carbons which is pyrolyzed at 250 and 700 °C were determined (270.2 and 686.7 m(2)/g, respectively. The surface area of hazelnut shell, which pyrolyzed at 700 °C after being activated with ZnCl2, was determined to be 736.49 m(2)/g. Results show that physical adsorption process is dominant for the activated carbon pyrolysis at 700 °C but the chemical adsorption is dominant for the activated carbon pyrolysis at lower degrees and for raw hazelnut shell. PMID:24801293

  4. Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements

    SciTech Connect

    Szrom, Fran; Falo, Gerald A.; Parkhurst, MaryAnn; Whicker, Jeffrey J.; Alberth, David P.

    2009-03-01

    Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the depleted uranium (DU) source term for the subsequent human health risk assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Correction factors for the disrupted equilibrium ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92.

  5. EMG activity and voluntary activation during knee-extensor concentric torque generation.

    PubMed

    Babault, Nicolas; Pousson, Michel; Michaut, Anne; Ballay, Yves; Hoecke, Jacques Van

    2002-04-01

    This study was designed to re-examine and compare the neural drive of the knee extensors during isokinetic concentric muscular actions by means of the twitch interpolation technique (activation level, AL) and surface electromyographic (EMG) recordings (root mean square, RMS). Torque, AL and RMS amplitudes of three knee extensors and one knee flexor were measured in nine subjects during maximal and sub-maximal voluntary contractions, performed under concentric (60 degrees.s(-1) and 120 degrees.s(-1); Con60 and Con120, respectively) and isometric (Iso) conditions. Mean (SD) maximal voluntary torque was significantly lower ( P<0.01) during concentric contractions [Con60: 208.6 (26.8) Nm and Con120: 184.7 (26.4) Nm] compared with isometric contractions [327.4 (52.0) Nm]. A significantly lower AL ( P<0.05) was recorded during Con60 [80.9 (8.8)%] compared with Iso [87.9 (5.1)%] and Con120 [88.2 (6.6)%] maximal contractions. Simultaneously, a lower knee extensor average RMS amplitudes (av.RMS) was measured during Con60 maximal contractions compared with Iso and Con120 maximal contractions. The antagonist biceps femoris RMS values were not different between maximal Iso, Con60 and Con120 contractions. During sub-maximal voluntary contractions, the RMS/torque relationships were similar whatever the muscle considered (vastus lateralis, vastus medialis or rectus femoris) and the AL/av.RMS relationships did not reveal any noticeable differences between each contractile condition. The results of the present study indicate that av.RMS and AL describe similarly the neural drive during maximal and sub-maximal efforts and indicate that during maximal voluntary efforts, neural drive is dependent upon concentric angular velocity (up to 120 degrees.s(-1)). Thus, our results suggest that when applying different contractile conditions, the torque output is regulated via complex interactions between intrinsic muscular properties and the neural drive.

  6. Arsenic Adsorption Equilibrium Concentration and Adsorption Rate of Activated Carbon Coated with Ferric-Aluminum Hydroxides

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Sugita, H.; Oguma, T.; Hara, J.; Takahashi, S.

    2015-12-01

    In some areas of developing countries, ground or well water contaminated with arsenic has been reluctantly used as drinking water. It is highly desirable that effective and inexpensive arsenic removal agents should be developed and provided to reduce the potential health risk. Previous studies demonstrated that activated carbon coated with ferric-aluminum hydroxides (Fe-Al-C) has high adsorptive potential for removal of arsenic. In this study, a series of experiments using Fe-Al-C were carried to discuss adsorption equilibrium time, adsorption equilibrium concentration and adsorption rate of arsenic for Fe-Al-C. Fe-Al-C used in this study was provided by Astec Co., Ltd. Powder reagent of disodium hydrogen arsenate heptahydrate was dissolved into ion-exchanged water. The solution was then further diluted with ion-exchanged water to be 1 and 10 mg/L as arsenic concentration. The pH of the solution was adjusted to be around 7 by adding HCl and/or NaOH. The solution was used as artificial arsenic contaminated water in two types of experiments (arsenic adsorption equilibrium and arsenic adsorption rate tests). The results of the arsenic equilibrium tests were showed that a time period of about 3 days to reach apparent adsorption equilibrium for arsenic. The apparent adsorption equilibrium concentration and adsorbed amount of arsenic on Fe-Al-C adsorbent could be estimated by application of various adsorption isotherms, but the distribution coefficient of arsenic between solid and liquid varies with experimental conditions such as initial concentration of arsenic and addition concentration of adsorbent. An adsorption rate equation that takes into account the reduction in the number of effective adsorption sites on the adsorbent caused by the arsenic adsorption reaction was derived based on the data obtained from the arsenic adsorption rate tests.

  7. Feasibility and analysis of bipolar concentric recording of electrohysterogram with flexible active electrode.

    PubMed

    Ye-Lin, Y; Alberola-Rubio, J; Prats-Boluda, G; Perales, A; Desantes, D; Garcia-Casado, Javier

    2015-04-01

    The conduction velocity and propagation patterns of the electrohysterogram (EHG) provide fundamental information on the electrophysiological condition of the uterus. However, the accuracy of these measurements can be impaired by both the poor spatial selectivity and sensitivity to the relative direction of the contraction propagation associated with conventional disc electrodes. Concentric ring electrodes could overcome these limitations. The aim of this study was to examine the feasibility of picking up surface EHG signals using a new flexible tripolar concentric ring electrode (TCRE), and to compare these signals with conventional bipolar recordings. Simultaneous recording of conventional bipolar signals and bipolar concentric EHG (BC-EHG) were carried out on 22 pregnant women. Signal bursts were characterized and compared. No significant differences were found between the channels in either duration or dominant frequency in the Fast Wave High frequency range. Nonetheless, the high pass filtering effect of the BC-EHG recordings gave lower frequency content between 0.1 and 0.2 Hz. Although the BC-EHG signal amplitude was about 5-7 times smaller than that of bipolar recordings, a similar signal-to-noise ratio was obtained. These results suggest that the flexible TCRE is able to pick up uterine electrical activity and could provide additional information for deducing the uterine electrophysiological condition.

  8. Feasibility and analysis of bipolar concentric recording of electrohysterogram with flexible active electrode.

    PubMed

    Ye-Lin, Y; Alberola-Rubio, J; Prats-Boluda, G; Perales, A; Desantes, D; Garcia-Casado, Javier

    2015-04-01

    The conduction velocity and propagation patterns of the electrohysterogram (EHG) provide fundamental information on the electrophysiological condition of the uterus. However, the accuracy of these measurements can be impaired by both the poor spatial selectivity and sensitivity to the relative direction of the contraction propagation associated with conventional disc electrodes. Concentric ring electrodes could overcome these limitations. The aim of this study was to examine the feasibility of picking up surface EHG signals using a new flexible tripolar concentric ring electrode (TCRE), and to compare these signals with conventional bipolar recordings. Simultaneous recording of conventional bipolar signals and bipolar concentric EHG (BC-EHG) were carried out on 22 pregnant women. Signal bursts were characterized and compared. No significant differences were found between the channels in either duration or dominant frequency in the Fast Wave High frequency range. Nonetheless, the high pass filtering effect of the BC-EHG recordings gave lower frequency content between 0.1 and 0.2 Hz. Although the BC-EHG signal amplitude was about 5-7 times smaller than that of bipolar recordings, a similar signal-to-noise ratio was obtained. These results suggest that the flexible TCRE is able to pick up uterine electrical activity and could provide additional information for deducing the uterine electrophysiological condition. PMID:25274161

  9. Concentrations and activity ratios of uranium isotopes in groundwater from Donana National Park, South of Spain

    SciTech Connect

    Bolivar, J. P.; Olias, M.; Gonzalez-Garcia, F.; Garcia-Tenorio, R.

    2008-08-07

    The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Donana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and {sup 210}Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that {sup 234}U/{sup 238}U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer.

  10. Structural Aspects of Antioxidant and Genotoxic Activities of Two Flavonoids Obtained from Ethanolic Extract of Combretum leprosum.

    PubMed

    Viau, Cassiana Macagnan; Moura, Dinara Jaqueline; Pflüger, Pricila; Facundo, Valdir Alves; Saffi, Jenifer

    2016-01-01

    Combretum leprosum Mart., a member of the Combretaceae family, is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates its antioxidant action and the safety of its use. We evaluated the antioxidant properties of the ethanolic extract (EE) from flowers of C. leprosum and its isolated products 5,3'-dihydroxy-3,7,4'-trimethoxyflavone (FCL2) and 5,3',4'-trihydroxy-3,7-dimethoxyflavone (FCL5) in Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. Their mutagenic activity was also assayed in S. cerevisiae, whereas cytotoxic and genotoxic properties were evaluated by MTT and Comet Assays, respectively, in V79 cells. We show that the EE, FCL2, and FCL5 have a significant protective effect against H2O2. FCL2 showed a better antioxidant action, which can be related to the activation of the 3'-OH in the presence of a methoxyl group at 4' position in the B-ring of the molecule, while flavonoids did not induce mutagenesis in yeast, and the EE was mutagenic at high concentrations. The toxicity of these compounds in V79 cells increases from FCL2 = FCL5 < EE; although not cytotoxic, FCL5 induced an increase in DNA damage. The antioxidant effect, along with the lower toxicity and the absence of genotoxicity, suggests that FCL2 could be suitable for pharmacological use. PMID:27478483

  11. Structural Aspects of Antioxidant and Genotoxic Activities of Two Flavonoids Obtained from Ethanolic Extract of Combretum leprosum

    PubMed Central

    Viau, Cassiana Macagnan; Moura, Dinara Jaqueline; Pflüger, Pricila; Facundo, Valdir Alves

    2016-01-01

    Combretum leprosum Mart., a member of the Combretaceae family, is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates its antioxidant action and the safety of its use. We evaluated the antioxidant properties of the ethanolic extract (EE) from flowers of C. leprosum and its isolated products 5,3′-dihydroxy-3,7,4′-trimethoxyflavone (FCL2) and 5,3′,4′-trihydroxy-3,7-dimethoxyflavone (FCL5) in Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. Their mutagenic activity was also assayed in S. cerevisiae, whereas cytotoxic and genotoxic properties were evaluated by MTT and Comet Assays, respectively, in V79 cells. We show that the EE, FCL2, and FCL5 have a significant protective effect against H2O2. FCL2 showed a better antioxidant action, which can be related to the activation of the 3′-OH in the presence of a methoxyl group at 4′ position in the B-ring of the molecule, while flavonoids did not induce mutagenesis in yeast, and the EE was mutagenic at high concentrations. The toxicity of these compounds in V79 cells increases from FCL2 = FCL5 < EE; although not cytotoxic, FCL5 induced an increase in DNA damage. The antioxidant effect, along with the lower toxicity and the absence of genotoxicity, suggests that FCL2 could be suitable for pharmacological use. PMID:27478483

  12. [The Xanthine Oxidase Inhibitory Activity and Hypouricemic Effects of Crude Drugs Obtained from the Silkworm in Mice].

    PubMed

    Tanaka, Ryuichirou; Miyata, Yuuma; Minakuchi, Naoki; Murakami, Ayako; Sakazaki, Fumitoshi

    2015-01-01

    This study evaluated the effects of crude drugs obtained from the silkworm in mice with oxonic acid-induced hyperuricemia using xanthine oxidase inhibitory activity and plasma uric acid levels. The plasma uric acid level was analyzed using an improved HPLC with UV detection (HPLC-UV) method, which enabled high-sensitivity analysis of a microliter of plasma. Using this method, we evaluated natural products administered orally to the hypouricemic mice. The plasma uric acid level of mice administered a water-soluble extract from silkworm larvae with botrytis (used in traditional Chinese medicine to reduce wind, lower blood pressure, and change platelet coagulation) was significantly lower than in the control group 1, 2, and 3 h after treatment. In addition, water soluble extracts from a fungus (NBRC 31161) metabolite and silkworm pupae and larvae reduced the plasma uric acid levels in mice compared with the control group.

  13. [The Xanthine Oxidase Inhibitory Activity and Hypouricemic Effects of Crude Drugs Obtained from the Silkworm in Mice].

    PubMed

    Tanaka, Ryuichirou; Miyata, Yuuma; Minakuchi, Naoki; Murakami, Ayako; Sakazaki, Fumitoshi

    2015-01-01

    This study evaluated the effects of crude drugs obtained from the silkworm in mice with oxonic acid-induced hyperuricemia using xanthine oxidase inhibitory activity and plasma uric acid levels. The plasma uric acid level was analyzed using an improved HPLC with UV detection (HPLC-UV) method, which enabled high-sensitivity analysis of a microliter of plasma. Using this method, we evaluated natural products administered orally to the hypouricemic mice. The plasma uric acid level of mice administered a water-soluble extract from silkworm larvae with botrytis (used in traditional Chinese medicine to reduce wind, lower blood pressure, and change platelet coagulation) was significantly lower than in the control group 1, 2, and 3 h after treatment. In addition, water soluble extracts from a fungus (NBRC 31161) metabolite and silkworm pupae and larvae reduced the plasma uric acid levels in mice compared with the control group. PMID:26423873

  14. Novel High-Speed High Pressure Torsion Technology for Obtaining Fe-Mn-Si-Cr Shape Memory Alloy Active Elements

    NASA Astrophysics Data System (ADS)

    Gurău, Gheorghe; Gurău, Carmela; Potecaşu, Octavian; Alexandru, Petrică; Bujoreanu, Leandru-Gheorghe

    2014-07-01

    This paper introduces an adapted high-speed high pressure torsion (HS-HPT) method of severe plastic deformation applied for obtaining shape memory alloy (SMA) active elements with revolution symmetry, able to develop axial displacement/force. Billets with circular crown forms were cut from Fe-28Mn-6Si-5Cr (mass%) SMA ingots and, by means of HS-HPT technology, were directly turned into modules, with truncated cone shell configurations. This process was performed, during time intervals of seconds, under the effect of high pressure (up to 1 GPa) cumulated with high rotation speed (hundreds of rotations per minute) applied on the active surfaces of sintered-carbide anvils, specially designed for this purpose. Due to pressure and friction, generated by rotation, the entire sample volume is heated and simultaneously deformed to final shape. During the process, microstructure fragmentation occurred enabling to obtain (ultra)fine grains and nanocrystalline areas, in spite of the heat developed by friction, which was removed by conduction at the contact surface between sample and anvils, before the occurrence of any recrystallization phenomena. When compressed between flat surfaces, the truncated cone modules developed a superelastic-like response, unique among Fe -Mn-Si base SMAs and, when heated in compressed state, they were able to develop either axial strokes or recovery forces by either free or constrained recovery shape memory effect (SME), respectively. By means of optical (OM) and scanning electron microscopy (SEM) marked structural changes caused by HT-HPT were revealed, along with fine and ultrafine crystalline grains. The presence of stress-induced ɛ-hexagonal close-packed ( hcp) martensite, together with nanocrystalline areas were confirmed by x-ray diffraction.

  15. Evaluation of anti-Candida activity of Vitis vinifera L. seed extracts obtained from wine and table cultivars.

    PubMed

    Simonetti, Giovanna; Santamaria, Anna Rita; D'Auria, Felicia Diodata; Mulinacci, Nadia; Innocenti, Marzia; Cecchini, Francesca; Pericolini, Eva; Gabrielli, Elena; Panella, Simona; Antonacci, Donato; Palamara, Anna Teresa; Vecchiarelli, Anna; Pasqua, Gabriella

    2014-01-01

    For the first time, grape seed extracts (GSEs), obtained from wine and table cultivars of Vitis vinifera L., cultured in experimental fields of Lazio and Puglia regions of Italy and grown in different agronomic conditions, have been tested on 43 Candida species strains. We demonstrated a significant correlation between the content of the flavan-3-ols in GSEs extracts, with a polymerization degree ≥ 4, and anti-Candida activity. Moreover, we demonstrated that GSEs, obtained from plants cultured with reduced irrigation, showed a content of polymeric flavan-3-ols >250 mg/g with geometric mean MIC values between 5.7 and 20.2 mg/L against Candida albicans reference strains. GSE, showing 573 mg/g of polymeric flavan-3-ols, has been tested in an experimental murine model of vaginal candidiasis by using noninvasive in vivo imaging technique. The results pointed out a significant inhibition of Candida albicans load 5 days after challenge. These findings indicate that GSEs with high content of polymeric flavan-3-ols can be used in mucosal infection as vaginal candidiasis.

  16. Classical Nuclear Hormone Receptor Activity as a Mediator of Complex Concentration Response Relationships for Endocrine Active Compounds

    PubMed Central

    Cookman, Clifford J.; Belcher, Scott M.

    2014-01-01

    Nonmonotonic concentration response relationships are frequently observed for endocrine active ligands that act via nuclear receptors. The curve of best fit for nonmonotonic concentration response relationships are often inverted U-shaped with effects at intermediate concentrations that are different from effects at higher or lower concentrations. Cytotoxicity is a major mode of action responsible for inverted U-shaped concentration response relationships. However, evidence suggests that ligand selectivity, activation of multiple molecular targets, concerted regulation of multiple opposing endpoints, and multiple ligand binding sites within nuclear receptors also contribute to nonmonotonic concentration response relationships of endocrine active ligands. This review reports the current understanding of mechanisms involved in classical nuclear receptor mediated nonmonotonic concentration response relationships with a focus on studies published between 2012 and 2014. PMID:25299165

  17. Melatonin concentrations in the two jugular veins, and relationship with the seasonal reproductive activity in goats.

    PubMed

    Zarazaga, L A; Celi, I; Guzmán, J L; Malpaux, B

    2010-07-15

    The authors investigated whether melatonin concentrations vary between the two jugular veins and whether absolute (nocturnal) or relative (nocturnal/diurnal ratio) plasma melatonin concentrations are associated with seasonal reproductive activity measured by oestrus or ovulatory activity in Payoya goats. Thirty-two adult Payoya goats were penned under natural photoperiod. Oestrus activity was tested daily using aproned males-twice a week plasma was sampled for progesterone. Melatonin plasma concentrations were studied at each equinox and solstice of the year in jugular samples taken simultaneously by venipuncture. Nocturnal and diurnal plasma melatonin concentrations from each jugular vein were assessed in 3 and 2 plasma samples per goat, respectively, taken at hourly intervals in each period. No differences in melatonin concentrations between the two veins were observed, but there was a significant interaction (P < 0.001) between jugular vein and animal in nocturnal melatonin concentrations. There was no effect of sampling period on melatonin concentrations and the coefficient of correlation between sampling periods was very high. The analyses performed indicated that neither absolute nor relative melatonin concentrations were related with the dates of onset or end of ovulatory/oestrus activity. Therefore, we concluded that in goats (1) melatonin concentrations are highly variable between jugular veins in the same individual but not in the general population, (2) melatonin concentrations are highly repeatable for each individual, and (3) absolute and relative amplitudes of melatonin concentrations are not linked to the seasonal breeding activity in Mediterranean goats. PMID:20451998

  18. Evolution in the concentration of activities in lithography

    NASA Astrophysics Data System (ADS)

    Levinson, Harry J.

    2016-03-01

    From a perusal of the proceedings of the SPIE Advanced Lithography Symposium, the progression of new concepts in lithographic technology can be seen. A new idea first appears in a few papers, and over time, there is an increase in the number of papers on the same topic. Eventually the method becomes commonplace, and the number of papers on the topic declines, as the idea becomes part of our industry's working knowledge. For example, one or two papers on resolution enhancement techniques (RETs) appeared in the proceedings of the Optical Microlithography Conference in 1989 and 1990. By 1994, the total number of papers had increased to 35. Early lithographers focused on practical issues, such as adhesion promotion and resist edge bead. The introduction of simulation software brought on the next era of lithography. This was followed by a period of time in which RETs were developed and brought to maturity. The introduction of optical proximity corrections (OPC) initiated the next major era of lithography. The traditional path for scaling by using shorter wavelengths, decreasing k1 and increasing numerical aperture has given way to the current era of optical multiple patterning and lithography-design co-optimization. There has been sufficient activity in EUV lithography R and D to justify a separate EUV Lithography Conference as part of the annual Advanced Lithography Symposium. Each era builds on the cumulative knowledge gained previously. Over time, there have been parallel developments in optics, exposure tools, resist, metrology and mask technology, many of which were associated with changes in the wavelength of light used for leading-edge lithography.

  19. Activities of chromium in molten copper at dilute concentrations by solid-state electrochemical cell

    NASA Astrophysics Data System (ADS)

    Inouye, T. K.; Fujiwara, H.; Iwase, M.

    1991-08-01

    In order to obtain the activities of chromium in molten copper at dilute concentrations (<0.008 chromium mole fractions), liquid copper was brought to equilibrium with molten CaCl2 + Cr2O3 slag saturated with Cr2O3 (s), at temperatures between 1423 and 1573 K, and the equilibrium oxygen partial pressures were measured by means of solid-oxide galvanic cells of the type Mo/Mo + MoO2/ZrO2(MgO)/(Cu + Cr))alloy + Cr2O3 + (CaCl2 + Cr2O3)slag/Mo. The free energy changes for the dissolution of solid chromium in molten copper at infinite dilution referred to 1 wt pct were determined as Cr (s) = Cr(1 wt pct, in Cu) and Δ G° = + 97,000 + 73.3 (T/K) ± 2,000 J mol-1.

  20. INSECTICIDAL ACTIVITY OF PROTEIN EXTRACTS OBTAINED FROM BULBS OF CHILEAN AMARYLLIDACEAE AGAINST TRIALEURODES VAPORARIORUM WESTWOOD AND PSEUDOCOCCUS VIBURNI SIGNORET.

    PubMed

    Zapata, N; Vargas, M; Coronado, A; Van Damme, E J M; Smagghe, G

    2015-01-01

    Entomotoxic proteins are produced by plants in defence against insect herbivory. Some carbohydrate-binding proteins exhibit strong insecticidal activity affecting the survival, growth, development and feeding behavior of phytophagous insects. The occurrence of entomotoxic lectins is well documented in the Amaryllidaceae, a plant family spread world-wide. In Chile, this family is represented by numerous species, many of which are also of high ornamental value. Protein extracts were obtained from bulbs of five different species of Chilean Amaryllidaceae. A dose-response assay was carried out with two important pests: the greenhouse whitefly Trialeurodes vaporariorum Westwood and the mealybug Pseudococcus viburni Signoret. The extracts were offered to insects in a liquid artificial diet for three days and the mortality was scored. The Phycella australis Ravenna extract caused the highest insecticidal activity (T. vaporariorum LC₅₀: 7200 µg/mL; P. viburni LC₅₀: 9500 µg/mL). Applied at 1000 µg/mL in the diet the P. australis extract did not repel feeding of these pests. A mannose-binding lectin isolated from the bulbs of P. australis proved to be moderately toxic for these pests (T. vaporariorum LC₅₀: 1127 µg/mL; P. viburni LC₅₀: 2320 µg/mL).

  1. Erythrocytes and cell line-based assays to evaluate the cytoprotective activity of antioxidant components obtained from natural sources.

    PubMed

    Botta, Albert; Martínez, Verónica; Mitjans, Montserrat; Balboa, Elena; Conde, Enma; Vinardell, M Pilar

    2014-02-01

    Oxidative stress can damage cellular components including DNA, proteins or lipids, and may cause several skin diseases. To protect from this damage and addressing consumer's appeal to natural products, antioxidants obtained from algal and vegetal extracts are being proposed as antioxidants to be incorporated into formulations. Thus, the development of reliable, quick and economic in vitro methods to study the cytoactivity of these products is a meaningful requirement. A combination of erythrocyte and cell line-based assays was performed on two extracts from Sargassum muticum, one from Ulva lactuca, and one from Castanea sativa. Antioxidant properties were assessed in erythrocytes by the TBARS and AAPH assays, and cytotoxicity and antioxidant cytoprotection were assessed in HaCaT and 3T3 cells by the MTT assay. The extracts showed no antioxidant activity on the TBARS assay, whereas their antioxidant capacity in the AAPH assay was demonstrated. On the cytotoxicity assays, extracts showed low toxicity, with IC50 values higher than 200μg/mL. C. sativa extract showed the most favourable antioxidant properties on the antioxidant cytoprotection assays; while S. muticum and U. lactuca extracts showed a slight antioxidant activity. This battery of methods was useful to characterise the biological antioxidant properties of these natural extracts.

  2. Effects of Temperature and Pore Structure on High Surface Area-Activated Carbon Obtained from Peanut Shells.

    PubMed

    Kalpana, D; Lee, Y S

    2016-03-01

    Activated carbon was synthesized from peanut shells by treating with H3PO4 with an intention to enhance the surface area and to find its electrochemical performance in EDLC as electrode material. The powdered peanut shells were pyrolyzed at three different temperatures namely 300 degrees C, 600 degrees C and 800 degrees C respectively. The structural and surface properties of the pyrolyzed carbon materials were studied using N2 adsorption/desorption, Raman, TEM and SEM analysis. There has been remarkable increase in the surface area of the carbon pyrolyzed at 600 degrees C due to the effect of pore generations. The surface area of the 600 degrees C pyrolyzed sample was found to be 1629 m2/g. The electrochemical properties of all the samples were evaluated by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge tests. The system showed excellent cycleability and a maximum specific capacitance of 291 Fg(-1) was obtained in a 0.1 M H2SO4 electrolyte solution. The effects of the various properties of the activated carbon on the EDLC performance are discussed. PMID:27455740

  3. Erythrocytes and cell line-based assays to evaluate the cytoprotective activity of antioxidant components obtained from natural sources.

    PubMed

    Botta, Albert; Martínez, Verónica; Mitjans, Montserrat; Balboa, Elena; Conde, Enma; Vinardell, M Pilar

    2014-02-01

    Oxidative stress can damage cellular components including DNA, proteins or lipids, and may cause several skin diseases. To protect from this damage and addressing consumer's appeal to natural products, antioxidants obtained from algal and vegetal extracts are being proposed as antioxidants to be incorporated into formulations. Thus, the development of reliable, quick and economic in vitro methods to study the cytoactivity of these products is a meaningful requirement. A combination of erythrocyte and cell line-based assays was performed on two extracts from Sargassum muticum, one from Ulva lactuca, and one from Castanea sativa. Antioxidant properties were assessed in erythrocytes by the TBARS and AAPH assays, and cytotoxicity and antioxidant cytoprotection were assessed in HaCaT and 3T3 cells by the MTT assay. The extracts showed no antioxidant activity on the TBARS assay, whereas their antioxidant capacity in the AAPH assay was demonstrated. On the cytotoxicity assays, extracts showed low toxicity, with IC50 values higher than 200μg/mL. C. sativa extract showed the most favourable antioxidant properties on the antioxidant cytoprotection assays; while S. muticum and U. lactuca extracts showed a slight antioxidant activity. This battery of methods was useful to characterise the biological antioxidant properties of these natural extracts. PMID:24134852

  4. Effects of Temperature and Pore Structure on High Surface Area-Activated Carbon Obtained from Peanut Shells.

    PubMed

    Kalpana, D; Lee, Y S

    2016-03-01

    Activated carbon was synthesized from peanut shells by treating with H3PO4 with an intention to enhance the surface area and to find its electrochemical performance in EDLC as electrode material. The powdered peanut shells were pyrolyzed at three different temperatures namely 300 degrees C, 600 degrees C and 800 degrees C respectively. The structural and surface properties of the pyrolyzed carbon materials were studied using N2 adsorption/desorption, Raman, TEM and SEM analysis. There has been remarkable increase in the surface area of the carbon pyrolyzed at 600 degrees C due to the effect of pore generations. The surface area of the 600 degrees C pyrolyzed sample was found to be 1629 m2/g. The electrochemical properties of all the samples were evaluated by cyclic voltammetry, impedance spectroscopy, and galvanostatic charge-discharge tests. The system showed excellent cycleability and a maximum specific capacitance of 291 Fg(-1) was obtained in a 0.1 M H2SO4 electrolyte solution. The effects of the various properties of the activated carbon on the EDLC performance are discussed.

  5. Characterization of anaerobic perchloroethylene dehalogenation activity at various substrate and perchloroethylene concentrations

    SciTech Connect

    Shah, M.M.; Gao, J.; Skeen, R.S.; Hooker, B.S.

    1995-12-31

    Research was undertaken to characterize anaerobic perchloroethylene (PCE) dehalogenation activity of microorganisms at various substrate and PCE concentrations. The concentrations of substrate, chlorinated ethylenes, and metabolic products such as methane, acetate, propionate, butyrate, hydrogen, and formate were monitored. The apparent relationship between major metabolic activities and dehalogenation was determined.

  6. Comparative studies on adsorptive removal of heavy metal ions by biosorbent, bio-char and activated carbon obtained from low cost agro-residue.

    PubMed

    Kırbıyık, Çisem; Pütün, Ayşe Eren; Pütün, Ersan

    2016-01-01

    In this study, Fe(III) and Cr(III) metal ion adsorption processes were carried out with three adsorbents in batch experiments and their adsorption performance was compared. These adsorbents were sesame stalk without pretreatment, bio-char derived from thermal decomposition of biomass, and activated carbon which was obtained from chemical activation of biomass. Scanning electron microscopy and Fourier transform-infrared techniques were used for characterization of adsorbents. The optimum conditions for the adsorption process were obtained by observing the influences of solution pH, adsorbent dosage, initial solution concentration, contact time and temperature. The optimum adsorption efficiencies were determined at pH 2.8 and pH 4.0 for Fe(III) and Cr(III) metal ion solutions, respectively. The experimental data were modelled by different isotherm models and the equilibriums were well described by the Langmuir adsorption isotherm model. The pseudo-first-order, pseudo-second-order kinetic, intra-particle diffusion and Elovich models were applied to analyze the kinetic data and to evaluate rate constants. The pseudo-second-order kinetic model gave a better fit than the others. The thermodynamic parameters, such as Gibbs free energy change ΔG°, standard enthalpy change ΔH° and standard entropy change ΔS° were evaluated. The thermodynamic study showed the adsorption was a spontaneous endothermic process. PMID:26819399

  7. Effects of increasing size and changing europium activator concentration in KCaI3 scintillator crystals

    NASA Astrophysics Data System (ADS)

    Lindsey, Adam C.; Zhuravleva, Mariya; Wu, Yuntao; Stand, Luis; Loyd, Matthew; Gokhale, Sasmit; Koschan, Merry; Melcher, Charles L.

    2016-09-01

    KCaI3:Eu crystals have been identified as very promising for use in spectroscopic detector applications related to nuclear nonproliferation and domestic security efforts. Initial studies have shown for small crystals a few mm3 in size with 3% europium dopant concentration, a high light yield of >70,000 ph/MeV and energy resolution of ≈3% at 662 keV is attainable which is comparable with the highest performance scintillators discovered. In this work, single crystals of KCaI3 with a range of Eu2+ doping between 0 and 5 at% substituting for Ca2+ were grown at 22 mm diameter and their performance for gamma-ray spectroscopy studied. Comparisons among crystals approximately Ø22 mm×22 mm (8.4 cm3 or ≈0.5 in3) provide a more accurate understanding of how scintillation performance changes with Eu doping and increased crystal size. KCaI3 in the undoped form is shown to be a highly efficient intrinsic scintillator with a defect-related emission at 404 nm which coexists with the Eu2+ 5d-4f emission in low dopant concentrations and is completely re-absorbed in more heavily doped crystals. For larger crystals, effects from self-absorption due to Eu activation become more evident by a near doubling of decay time for 0.5 in3 crystals as the activator is increased from 0.5 to 5.0 at% Eu. Comparisons of pulse-height spectra obtained for Ø22 mm×22 mm cylinders with varying Eu concentration suggests best performance is achieved using lower Eu additions closer to 0.5-1.0 at%. Using a modified crystal packaging featuring an offset reflector geometry, 0.5 in3 crystals of KCaI3:Eu can attain under 4% energy resolution at 662 keV.

  8. Estimating volatile organic compound concentrations in selected microenvironments using time-activity and personal exposure data.

    PubMed

    Sexton, Ken; Mongin, Steven J; Adgate, John L; Pratt, Gregory C; Ramachandran, Gurumurthy; Stock, Thomas H; Morandi, Maria T

    2007-03-01

    Repeated measures of personal exposure to 14 volatile organic compounds (VOC) were obtained over 3 seasons for 70 healthy, nonsmoking adults living in Minneapolis-St. Paul. Matched data were also available for participants' time-activity patterns, and measured VOC concentrations outdoors in the community and indoors in residences. A novel modeling approach employing hierarchical Bayesian techniques was used to estimate VOC concentrations (posterior mode) and variability (credible intervals) in five microenvironments: (1) indoors at home; (2) indoors at work/school; (3) indoors in other locations; (4) outdoors in any location; and (5) in transit. Estimated concentrations tended to be highest in "other" indoor microenvironments (e.g., grocery stores, restaurants, shopping malls), intermediate in the indoor work/school and residential microenvironments, and lowest in the outside and in-transit microenvironments. Model estimates for all 14 VOC were reasonable approximations of measured median concentrations in the indoor residential microenvironment. The largest predicted contributor to cumulative (2-day) personal exposure for all 14 VOC was the indoor residential environment. Model-based results suggest that indoors-at-work/school and indoors-at-other-location microenvironments were the second or third largest contributors for all VOC, while the outside-in-any-location and in-transit microenvironments appeared to contribute negligibly to cumulative personal exposure. Results from a mixed-effects model indicate that being in or near a garage increased personal exposure to o-xylene, m/p-xylene, benzene, ethylbenzene, and toluene, and leaving windows and doors at home open for 6 h or more decreased personal exposure to 13 of 14 VOC, all except trichloroethylene.

  9. Daily and seasonal variations in radon activity concentration in the soil air.

    PubMed

    Műllerová, Monika; Holý, Karol; Bulko, Martin

    2014-07-01

    Radon activity concentration in the soil air in the area of Faculty of Mathematics, Physics and Informatics (FMPI) in Bratislava, Slovak Republic, has been continuously monitored since 1994. Long-term measurements at a depth of 0.8 m and short-term measurements at a depth of 0.4 m show a high variability in radon activity concentrations in the soil. The analysis of the data confirms that regular daily changes in radon activity concentration in the soil air depend on the daily changes in atmospheric pressure. It was also found that the typical annual courses of the radon activity concentration in the soil air (with summer minima and winter maxima) were disturbed by mild winter and heavy summer precipitation. Influence of precipitation on the increase in the radon activity concentration in the soil air was observed at a depth of 0.4 m and subsequently at a depth of 0.8 m.

  10. The loading of coordination complex modified polyoxometalate nanobelts on activated carbon fiber: a feasible strategy to obtain visible light active and highly efficient polyoxometalate based photocatalysts.

    PubMed

    Lu, Tingting; Xu, Xinxin; Li, Huili; Li, Zhenyu; Zhang, Xia; Ou, Jinzhao; Mei, Mingliang

    2015-02-01

    To enhance the photocatalytic properties of coordination complex modified polyoxometalates (CC/POMs) in the visible light region, its nanobelts (CC/POMNBs) were loaded on activated carbon fiber (ACF) through a simple colloidal blending process. The resulting coordination complex modified polyoxometalate nanobelts loaded activated carbon fiber composite materials (CC/POMNBs/ACF) exhibited dramatic photocatalytic activity for the degradation of rhodamine B (RhB) under visible light irradiation. Optical and electrochemical methods illustrated the enhanced photocatalytic activity of CC/POMNBs/ACF, which originates from the high separation efficiency of the photogenerated electrons and holes on the interface of the CC/POMNBs and ACF, which results from the synergistic effects between them. In the composite material, the role of ACF could be described as a photosensitizer and a good electron transporter. Furthermore, the influence of the mass ratio between the CC/POMNBs and ACF on the photocatalytic performance of the resulting composite material was discussed, and an ideal value to obtain highly efficient photocatalysts was obtained. The results suggested that the loading of CC/POMNBs on the surface of ACF would be a feasible strategy to enhance their photocatalytic activity.

  11. Analysis of Bio-Obtainable Endocrine Disrupting Metals in River Water and Sediment, Sewage Influent/Effluent, Sludge, Leachate, and Concentrated Leachate, in the Irish Midlands Shannon Catchment

    PubMed Central

    Reid, Antoinette M.; Brougham, Concepta A.; Fogarty, Andrew M.; Roche, James J.

    2009-01-01

    The application of an acid digestion and subsequent solid-phase extraction (SPE) procedure were implemented as preliminary treatments prior to quantifying the levels of potentially endocrine disrupting metals (EDMs) in a variety of solid and liquid matrices. These included (solid) river sediment, leachate sediment and sewage sludge and also (liquid) river water, landfill leachate, concentrated leachate, sewage influent, and sewage effluent, sampled in the Irish Midlands. The total concentrations of cobalt (Co), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), zinc (Zn), and manganese (Mn), after extraction and preconcentration, were determined by atomic absorption spectroscopy (AAS). Mercury (Hg) in sediment and sludge was determined using cold-vapour atomic fluorescence spectroscopy (AFS). For sewage sludge maximum values (mg/kgdw) of 4700 Ni, 1642 Mn, 100.0 Cd, 3400 Zn, 36.70 Co, 750.0 Pb, 485.8 Cr, and 1003 Cu were determined whilst in leachate sediment, maximum values (mg/kgdw) of 32.10 Ni, 815.0 Mn, 32.78 Cd, 230.3 Zn, 26.73 Co, 3525 Pb, 124.9 Cr, and 50.13 Cu were found. Over several months, the data showed elevated levels in sewage influents, effluents, and sludges compared to a battery of adjacent river water samples and corresponding sediments. There was a definite trend for target values for sediments to be exceeded, while intervention values were only exceeded for cadmium. Overall the pattern in terms of concentration was sewage > leachate > river matrices. A nonparametric assessment of the effect of sewage treatment method on median metal levels in sludge revealed statistically significant differences at the 95% level of confidence for Co, Cr, and Hg and at the 90% level of confidence for Cd. PMID:20150974

  12. Soluble interleukin-2 receptor in Crohn's disease: relation of serum concentrations to disease activity.

    PubMed

    Crabtree, J E; Juby, L D; Heatley, R V; Lobo, A J; Bullimore, D W; Axon, A T

    1990-09-01

    Serum concentrations of soluble interleukin-2 receptor (sIL-2R) were measured as a marker of immune activation in a group of 30 patients with Crohn's disease. sIL-2R concentrations were determined by enzyme linked immunosorbent assay during periods of active and inactive disease and correlated with standard parameters of disease activity. Serum concentrations of sIL-2R were significantly raised in patients with active Crohn's disease compared with patients with inactive disease (p less than 0.001) and control subjects. There was a significant correlation between serum sIL-2R concentrations and disease activity as assessed by the Harvey-Bradshaw index (r = 0.42, p less than 0.01), platelet numbers (r = 0.49, p less than 0.01), and orosomucoid (r = 0.47, p less than 0.01), alpha 1 antitrypsin (r = 0.44, p less than 0.01), and C reactive protein concentrations (r = 0.48, p less than 0.001) but not with the erythrocyte sedimentation rate. Measurement of serum sIL-2R concentration is a simple and useful laboratory means of assessing disease activity. Raised concentrations in patients with active Crohn's disease is further evidence for in vivo immune activation occurring in this disease.

  13. Asymmetric synthesis of aromatic β-amino acids using ω-transaminase: Optimizing the lipase concentration to obtain thermodynamically unstable β-keto acids.

    PubMed

    Mathew, Sam; Jeong, Seong-Su; Chung, Taeowan; Lee, Sang-Hyeup; Yun, Hyungdon

    2016-01-01

    Synthesized aromatic β-amino acids have recently attracted considerable attention for their application as precursors in many pharmacologically relevant compounds. Previous studies on asymmetric synthesis of aromatic β-amino acids using ω-transaminases could not be done efficiently due to the instability of β-keto acids. In this study, a strategy to circumvent the instability problem of β-keto acids was utilized to generate β-amino acids efficiently via asymmetric synthesis. In this work, thermodynamically stable β-ketoesters were initially converted to β-keto acids using lipase, and the β-keto acids were subsequently aminated using ω-transaminase. By optimizing the lipase concentration, we successfully overcame the instability problem of β-keto acids and enhanced the production of β-amino acids. This strategy can be used as a general approach to efficiently generate β-amino acids from β-ketoesters.

  14. Cytotoxic proteins combined with prodigiosin obtained from Serratia marcescens have both broad and selective cytotoxic activity on tumor cells.

    PubMed

    Abrahantes-Pérez, M C; Reyes-González, J; Véliz Ríos, G; Bequet-Romero, M; Gómez Riera, R; Anais Gasmury, C; Huerta, V; González, L J; Canino, C; Garcia, J; Váldez, J; Reyes, B; Váldes, R; Martínez, E

    2006-04-01

    Cytotoxic proteins and prodigiosin obtained from Serratia marcescens strains are known to induce tumor cell death, nevertheless its combination has not been studied. In this paper we evaluate the combined effects of these molecules in a panel of tumor cell lines. The results showed a marked inhibitory effect on the growth of tumor cell lines derived from tumors (i.e., melanoma) which are highly resistant to conventional anticancer drugs, while normal cells were less sensitive than tumor cells. TUNEL (TdT-mediated dUTP nick end labeling) and electrophoresis of HEp-2 cell DNA treated with MG2327 preparation [containing the P50 protein belonging to the serralysins and prodigiosin, from S. marcescens CMIB4202] showed a pattern of DNA fragments typically associated with apoptosis. Interestingly, prodigiosin enhanced by 1.6-fold the cytotoxic effect of P50 when acting in combination on HEp-2 cells. The broad cytotoxic activity of the combination on tumor cells as well as its selectivity open new frontiers in cancer therapy.

  15. Influence of dietary intake and physical activity on annual rhythm of human blood cholesterol concentrations.

    PubMed

    Blüher, M; Hentschel, B; Rassoul, F; Richter, V

    2001-05-01

    Seasonal variation in the plasma total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) have been repeatedly reported, with contradictory results regarding the pattern of seasonal variation of these parameters. Furthermore, it is still not well established whether the variation is due to changes in the nutrition or changes in physical activity depending on the season. The aim of this study was therefore to determine plasma TC and HDL-C in different groups of healthy participants: 19 vegetarians with a constant diet independent of the season, 14 athletes with almost constant physical activity over the year, and 114 controls in the age groups 20-26 years (mean age 24 + 1.5 years) and 40-48 years (mean age 44.3 + 2.1 years). Over 2 years, blood samples were collected every 2-3 months and were analyzed for plasma TC and HDL-C. At all visits, body mass index (BMI) and waist-to-hip ratio (WHR) were calculated, and nutrition and physical activity profiles were obtained. The seasonal model was calculated using object-oriented software for the analysis of longitudinal data in S (OSWALD); multiple regression analysis was used to determine the influence of age, gender, diet, and physical activity on seasonal changes of the lipid parameters. In all groups, we found an annual rhythm of the plasma TC and HDL-C concentrations, which can be mathematically described by a sine curve with a maximum in winter and a minimum in summer. This rhythm was independent of the age, gender, BMI, diet, or physical activity. The observed seasonal differences between the maximum and the minimum were about 5%-10% for TC and about 5%-8% for HDL-C concentration. These differences were greater than the determined circadian (TC 3.5%, HDL-C 4%) and day-to-day changes for TC and HDL-C (coefficient of variation <5% for both). In conclusion, annual rhythm of TC and HDL-C is not primarily induced by seasonal differences in dietary intake or physical activity. Therefore, the annual rhythm in

  16. Effect of the active-ion concentration on the lasing dynamics of holmium fibre lasers

    SciTech Connect

    Kurkov, Andrei S; Sholokhov, E M; Marakulin, A V; Minashina, L A

    2010-12-09

    The lasing dynamics of fibre lasers with a core based on quartz glass doped with holmium ions to concentrations in the range of 10{sup 19}-10{sup 20} cm{sup -3} is investigated. It is shown that fibre lasers with a high concentration of active holmium ions generate pulses, but a decrease in the holmium concentration changes the lasing from pulsed to cw regime. At the same time, a decrease in the active-ion concentration and the corresponding increase in the fibre length in the cavity reduce the lasing efficiency. (lasers)

  17. Phase transformations during HLnTiO{sub 4} (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    SciTech Connect

    Silyukov, Oleg I. Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-15

    Layered HLnTiO{sub 4} (Ln=La, Nd) compounds belonging to Ruddlesden–Popper phases were found to form partially hydrated compounds Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O during thermal dehydration as well as defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7} as final products. Further heating of metastable defect Ln{sub 2}□Ti{sub 2}O{sub 7} substances leads to the formation of pyrochlore-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}activity in the order of HLnTiO{sub 4}obtained. • We examined the photocatalytic activity of all obtained compounds. The hydrogen evolution rate increased in the course of the structure changes during thermolysis.

  18. Variability of atmospheric krypton-85 activity concentrations observed close to the ITCZ in the southern hemisphere.

    PubMed

    Bollhöfer, A; Schlosser, C; Ross, J O; Sartorius, H; Schmid, S

    2014-01-01

    Krypton-85 activity concentrations in surface air have been measured at Darwin, which is located in northern Australia and is influenced by seasonal monsoonal activity. Measurements between August 2007 and May 2010 covered three wet seasons. The mean activity concentration of krypton-85 measured during this period was 1.31±0.02Bqm(-3). A linear model fitted to the average monthly data, using month and monsoon as predictors, shows that krypton-85 activity concentration measured during the sampling period has declined by 0.01Bqm(-3) per year. Although there is no statistically significant difference in mean activity concentration of krypton-85 between wet and dry season, the model implies that activity concentration is higher by about 0.015Bqm(-3) during months influenced by the monsoon when a north westerly flow prevails. Backward dispersion runs using the Lagrangian particle dispersion model Hysplit4 highlight possible source regions during an active monsoon located deep in the northern hemisphere, and include reprocessing facilities in Japan and India. However, the contribution of these facilities to krypton-85 activity concentrations in Darwin would be less than 0.003Bqm(-3).

  19. Effects of high dietary sulphur on enzyme activities, selenium concentrations and body weights of cattle.

    PubMed Central

    Khan, A A; Lovejoy, D; Sharma, A K; Sharma, R M; Prior, M G; Lillie, L E

    1987-01-01

    This study was designed to assess the effects of a moderate increase in dietary sulphur (S) in cattle. Twelve animals were initially fed a basal concentrate (S = 0.2%) and then divided into two groups; one fed basal and the other high S (S = 0.75%) concentrates. Health, body weight gains, and activities of erythrocyte enzymes-glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glucose-6-phosphate dehydrogenase (G6PD), acetylcholinesterase (AChE), plasma- asparate aminotransferase (AST), and whole blood concentrations of selenium (Se) were monitored at various stages of the study. Marked increases in the activities of GSH-Px, SOD and G6PD from the pretrial values were observed upon initial feeding of basal concentrate diet. Sex related differences were not evident in enzyme activities and Se concentrations of the blood. A high linear correlation (r = 0.92) between averages of GSH-Px activity and Se concentration of blood was observed in both sexes. Increasing the amount of S in the concentrate diet (from 0.2 to 0.75%) did not produce any statistically significant change in enzyme activities and Se concentrations, body weight gains, and health of the cattle during the 85 days feeding period. The results indicate that a moderate increase in the dietary S would not impair Se and copper status or cause related disorders in cattle. PMID:3607649

  20. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    NASA Astrophysics Data System (ADS)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-04-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

  1. Pharmaceutical gel analysis by NIR spectroscopy. Determination of the active principle and low concentration of preservatives.

    PubMed

    Blanco, M; Alcalá, M; Bautista, M

    2008-04-23

    Near infrared spectroscopy has proved highly suitable for the analysis of pharmaceutical formulations. However, its limited sensitivity can severely restrict its scope of application. In this work, we determine the active principle and two preservatives in a pharmaceutical preparation available as a hydrogel. The matrix of the pharmaceutical preparation exhibits strong absorption in the NIR spectral region; also, the two preservatives (parabens) are very similar in chemical and spectral terms, and present at low concentrations in the pharmaceutical. These complications make it rather difficult to accurately quantify the active principle and the preservatives, which can only be accomplished by using an effective design in order to prepare the samples to be included in the calibration set and select the optimum spectral range for measuring each analyte. The evaporation of solvents during the measurement process produces increasing errors related with sample's air exposition; the introductions of new samples with a wider range of the volatile components correct this effect. An ANOVA of the predictions obtained with the new models shows that correct the error due to evaporation. The proposed method was validated for the analytical control of the studied preparation.

  2. Effect of oxygen concentration on nitrification and denitrification in single activated sludge flocs.

    PubMed

    Satoh, Hisashi; Nakamura, Yoshiyuki; Ono, Hideki; Okabe, Satoshi

    2003-09-01

    Simultaneous nitrification and denitrification (SND) was investigated in the single aeration tank of a municipal wastewater treatment plant. Microelectrode measurements and batch experiments were performed to test for the presence of SND. Microelectrodes recorded the presence of O(2) concentration gradients in individual activated sludge flocs. When the O(2) concentration in the bulk liquid was <45 microM, anoxic zones were detected within flocs with a larger diameter (approximately 3000 microm). The O(2) penetration depth in the floc was found to be dependent on the O(2) concentration in the bulk liquid. Nitrification was restricted to the oxic zones, whereas denitrification occurred mainly in the anoxic zones. The nitrification rate of the activated sludge increased with increasing O(2) concentration in the bulk liquid, up to 40 microM, and remained constant thereafter. SND was observed in the aerated activated sludge when O(2) concentration was in the range of 10 to 35 microM.

  3. Effect of sodium fluoride ingestion on malondialdehyde concentration and the activity of antioxidant enzymes in rat erythrocytes.

    PubMed

    Morales-González, José A; Gutiérrez-Salinas, José; García-Ortiz, Liliana; Del Carmen Chima-Galán, María; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna Y

    2010-06-11

    Fluoride intoxication has been shown to produce diverse deleterious metabolic alterations within the cell. To determine the effects of sodium fluoride (NaF) treatment on malondialdehyde (MDA) levels and on the activity of antioxidant enzymes in rat erythrocytes, Male Wistar rats were treated with 50 ppm of NaF or were untreated as controls. Erythrocytes were obtained from rats sacrificed weekly for up to eight weeks and the concentration of MDA in erythrocyte membrane was determined. In addition, the activity of the enzymes superoxide, dismutase, catalase, and glutathione peroxidase were determined. Treatment with NaF produces an increase in the concentration of malondialdehyde in the erythrocyte membrane only after the eight weeks of treatment. On the other hand, antioxidant enzyme activity was observed to increase after the fourth week of NaF treatment. In conclusion, intake of NaF produces alterations in the erythrocyte of the male rat, which indicates induction of oxidative stress.

  4. Effect of Sodium Fluoride Ingestion on Malondialdehyde Concentration and the Activity of Antioxidant Enzymes in Rat Erythrocytes

    PubMed Central

    Morales-González, José A.; Gutiérrez-Salinas, José; García-Ortiz, Liliana; del Carmen Chima-Galán, María; Madrigal-Santillán, Eduardo; Esquivel-Soto, Jaime; Esquivel-Chirino, César; González-Rubio, Manuel García-Luna y

    2010-01-01

    Fluoride intoxication has been shown to produce diverse deleterious metabolic alterations within the cell. To determine the effects of sodium fluoride (NaF) treatment on malondialdehyde (MDA) levels and on the activity of antioxidant enzymes in rat erythrocytes, Male Wistar rats were treated with 50 ppm of NaF or were untreated as controls. Erythrocytes were obtained from rats sacrificed weekly for up to eight weeks and the concentration of MDA in erythrocyte membrane was determined. In addition, the activity of the enzymes superoxide, dismutase, catalase, and glutathione peroxidase were determined. Treatment with NaF produces an increase in the concentration of malondialdehyde in the erythrocyte membrane only after the eight weeks of treatment. On the other hand, antioxidant enzyme activity was observed to increase after the fourth week of NaF treatment. In conclusion, intake of NaF produces alterations in the erythrocyte of the male rat, which indicates induction of oxidative stress. PMID:20640162

  5. A neutron activation analysis of iridium concentration in Yamato carbonaceous chondrite

    NASA Astrophysics Data System (ADS)

    Yabushita, S.; Wada, K.; Moriyama, H.; Takeuchi, K.

    1988-09-01

    Iridium concentration in extra-terrestrial bodies is an important quantity in relation to Ir-rich geological layers. Ir concentration of a Yamato carbonaceous chondrite (Y-793321) has been measured by a neutron activation method. The measurement yields a value (0.57±0.06) μg per gramme for the chondrite.

  6. Effect of Radionuclide Activity Concentration on PET-CT Image Uniformity

    PubMed Central

    Hasford, Francis; Wyk, Bronwin Van; Mabhengu, Thulani; Vangu, Mboyo Di Tamba; Kyere, Augustine Kwame; Amuasi, John Humphrey

    2016-01-01

    Assessment of radionuclide activity concentration on positron emission tomography-computedr tomography (PET-CT) image uniformity has been carried out quantitatively. Tomographic PET-CT images of cylindrical phantom containing F-18 fluorodeoxyglucose (FDG) activity concentration was acquired and used for the assessment. Activity concentrations were varied and PET-CT images were acquired at the constant acquisition parameters of time, matrix size, and reconstruction algorithm, respectively. Using midtransaxial image slices, quantitative index of nonuniformity (NU), and coefficient of uniformity variation were estimated for the different activity concentrations. Maximum NUs of 17.6%, 26.3%, 32.7%, 36.2%, and 38.5% were estimated for activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL, respectively. The coefficient of uniformity variation established an inverse quadratic relationship with activity concentration. Activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL produced uniformity variations of 1.47%, 2.52%, 4.23%, 5.12%, and 4.98%, respectively. Increasing activity concentration resulted in decreasing coefficient of uniformity and hence, an increase in image uniformity. The uniformity estimates compared well with the standards set internationally. PMID:27134558

  7. On the calculation of activity concentrations and nuclide ratios from measurements of atmospheric radioactivity.

    PubMed

    Axelsson, A; Ringbom, A

    2014-09-01

    Motivated by the need for consistent use of concepts central to the reporting of results from measurements of atmospheric radioactivity, we discuss some properties of the methods commonly used. Different expressions for decay correction of the activity concentration for parent-daughter decay pairs are presented, and it is suggested that this correction should be performed assuming parent-daughter ingrowth in the sample during the entire measurement process. We note that, as has already been suggested by others, activities rather than activity concentrations should be used when nuclide ratios are calculated. In addition, expressions that can be used to transform activity concentrations to activity ratios are presented. Finally we note that statistical uncertainties for nuclide ratios can be properly calculated using the exact solution to the problem of confidence intervals for a ratio of two jointly normally distributed variables, the so-called Fieller׳s theorem.

  8. Equilibrium sampling of environmental pollutants in fish: comparison with lipid-normalized concentrations and homogenization effects on chemical activity.

    PubMed

    Jahnke, Annika; Mayer, Philipp; Adolfsson-Erici, Margaretha; McLachlan, Michael S

    2011-07-01

    Equilibrium sampling of organic pollutants into the silicone polydimethylsiloxane (PDMS) has recently been applied in biological tissues including fish. Pollutant concentrations in PDMS can then be multiplied with lipid/PDMS distribution coefficients (D(Lipid,PDMS) ) to obtain concentrations in fish lipids. In the present study, PDMS thin films were used for equilibrium sampling of polychlorinated biphenyls (PCBs) in intact tissue of two eels and one salmon. A classical exhaustive extraction technique to determine lipid-normalized PCB concentrations, which assigns the body burden of the chemical to the lipid fraction of the fish, was additionally applied. Lipid-based PCB concentrations obtained by equilibrium sampling were 85 to 106% (Norwegian Atlantic salmon), 108 to 128% (Baltic Sea eel), and 51 to 83% (Finnish lake eel) of those determined using total extraction. This supports the validity of the equilibrium sampling technique, while at the same time confirming that the fugacity capacity of these lipid-rich tissues for PCBs was dominated by the lipid fraction. Equilibrium sampling was also applied to homogenates of the same fish tissues. The PCB concentrations in the PDMS were 1.2 to 2.0 times higher in the homogenates (statistically significant in 18 of 21 cases, p < 0.05), indicating that homogenization increased the chemical activity of the PCBs and decreased the fugacity capacity of the tissue. This observation has implications for equilibrium sampling and partition coefficients determined using tissue homogenates.

  9. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    SciTech Connect

    Armynah, B. Tahir, D. Jaya, N.

    2014-09-25

    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  10. A novel method for concentration evaluation of reading behaviors with electrical activity recorded on the scalp.

    PubMed

    Lin, Chern-Sheng; Lai, Yu-Chen; Lin, Jung-Chih; Wu, Pin-Yi; Chang, Hsing-Cheng

    2014-04-01

    In this paper, a concentration evaluation of reading behaviors with electrical signal detection on the head is presented. The electrode signal is extracted by brain-computer-interface (BCI) to monitor the user's degree of concentration, where the user is reminded by sound to concentrate, or teaching staffs are reminded to help users improve reading habits, in order to facilitate the user's ability to concentrate. The digital signal processing methods, such as the Kalman Filter, Fast Fourier Transform, the Hamming window, the average value of the total energy of a frame, correlation coefficient, and novel judgment algorithm are used to obtain the corresponding parameters of concentration evaluation. Users can correct their manner of reading with reminders. The repeated test results may be expected to lie with a probability of 95%. Such model training results in better learning effect. PMID:24631218

  11. A novel method for concentration evaluation of reading behaviors with electrical activity recorded on the scalp.

    PubMed

    Lin, Chern-Sheng; Lai, Yu-Chen; Lin, Jung-Chih; Wu, Pin-Yi; Chang, Hsing-Cheng

    2014-04-01

    In this paper, a concentration evaluation of reading behaviors with electrical signal detection on the head is presented. The electrode signal is extracted by brain-computer-interface (BCI) to monitor the user's degree of concentration, where the user is reminded by sound to concentrate, or teaching staffs are reminded to help users improve reading habits, in order to facilitate the user's ability to concentrate. The digital signal processing methods, such as the Kalman Filter, Fast Fourier Transform, the Hamming window, the average value of the total energy of a frame, correlation coefficient, and novel judgment algorithm are used to obtain the corresponding parameters of concentration evaluation. Users can correct their manner of reading with reminders. The repeated test results may be expected to lie with a probability of 95%. Such model training results in better learning effect.

  12. Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part III: leucocyte activation: a new feature for platelet concentrates?

    PubMed

    Dohan, David M; Choukroun, Joseph; Diss, Antoine; Dohan, Steve L; Dohan, Anthony J J; Mouhyi, Jaafar; Gogly, Bruno

    2006-03-01

    Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. In this third article, we investigate the immune features of this biomaterial. During PRF processing, leucocytes could also secrete cytokines in reaction to the hemostatic and inflammatory phenomena artificially induced in the centrifuged tube. We therefore undertook to quantify 5 significant cell mediators within platelet poor plasma supernatant and PRF clot exudate serum: 3 proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha), an antiinflammatory cytokine (IL-4), and a key growth promoter of angiogenesis (VEGF). Our data are correlated with that obtained in plasma (nonactivated blood) and in sera (activated blood). These initial analyses revealed that PRF could be an immune regulation node with inflammation retrocontrol abilities. This concept could explain the reduction of postoperative infections when PRF is used as surgical additive.

  13. Alteration of natural (37)Ar activity concentration in the subsurface by gas transport and water infiltration.

    PubMed

    Guillon, Sophie; Sun, Yunwei; Purtschert, Roland; Raghoo, Lauren; Pili, Eric; Carrigan, Charles R

    2016-05-01

    High (37)Ar activity concentration in soil gas is proposed as a key evidence for the detection of underground nuclear explosion by the Comprehensive Nuclear Test-Ban Treaty. However, such a detection is challenged by the natural background of (37)Ar in the subsurface, mainly due to Ca activation by cosmic rays. A better understanding and improved capability to predict (37)Ar activity concentration in the subsurface and its spatial and temporal variability is thus required. A numerical model integrating (37)Ar production and transport in the subsurface is developed, including variable soil water content and water infiltration at the surface. A parameterized equation for (37)Ar production in the first 15 m below the surface is studied, taking into account the major production reactions and the moderation effect of soil water content. Using sensitivity analysis and uncertainty quantification, a realistic and comprehensive probability distribution of natural (37)Ar activity concentrations in soil gas is proposed, including the effects of water infiltration. Site location and soil composition are identified as the parameters allowing for a most effective reduction of the possible range of (37)Ar activity concentrations. The influence of soil water content on (37)Ar production is shown to be negligible to first order, while (37)Ar activity concentration in soil gas and its temporal variability appear to be strongly influenced by transient water infiltration events. These results will be used as a basis for practical CTBTO concepts of operation during an OSI.

  14. Concentration evolution of pharmaceutically active compounds in raw urban and industrial wastewater.

    PubMed

    Camacho-Muñoz, Dolores; Martín, Julia; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

    2014-09-01

    The distribution of pharmaceutically active compounds in the environment has been reported in several works in which wastewater treatment plants have been identified as the main source of these compounds to the environment. The concentrations of these compounds in influent wastewater can vary widely not only during the day but also along the year, because of the seasonal-consumption patterns of some pharmaceuticals. However, only few studies have attempted to assess the hourly variability of the concentrations of pharmaceutically active compounds in wastewater. In this work, the distribution and seasonal and hourly variability of twenty-one pharmaceuticals, belonging to seven therapeutic groups, have been investigated in urban and industrial wastewater. The highest concentrations of pharmaceutically active compounds, except salicylic acid, were found in urban wastewater, especially in the case of anti-inflammatory drugs and caffeine. The highest concentrations of salicylic acid were measured in industrial wastewater, reaching concentration levels up to 3295μgL(-)(1). The studied pharmaceutically active compounds showed different distribution patterns during winter and summer periods. Temporal variability of pharmaceutically active compounds during a 24-h period showed a distribution in concordance with their consumption and excretion patterns, in the case of urban wastewater, and with the schedule of industrial activities, in the case of industrial wastewater.

  15. Alteration of natural (37)Ar activity concentration in the subsurface by gas transport and water infiltration.

    PubMed

    Guillon, Sophie; Sun, Yunwei; Purtschert, Roland; Raghoo, Lauren; Pili, Eric; Carrigan, Charles R

    2016-05-01

    High (37)Ar activity concentration in soil gas is proposed as a key evidence for the detection of underground nuclear explosion by the Comprehensive Nuclear Test-Ban Treaty. However, such a detection is challenged by the natural background of (37)Ar in the subsurface, mainly due to Ca activation by cosmic rays. A better understanding and improved capability to predict (37)Ar activity concentration in the subsurface and its spatial and temporal variability is thus required. A numerical model integrating (37)Ar production and transport in the subsurface is developed, including variable soil water content and water infiltration at the surface. A parameterized equation for (37)Ar production in the first 15 m below the surface is studied, taking into account the major production reactions and the moderation effect of soil water content. Using sensitivity analysis and uncertainty quantification, a realistic and comprehensive probability distribution of natural (37)Ar activity concentrations in soil gas is proposed, including the effects of water infiltration. Site location and soil composition are identified as the parameters allowing for a most effective reduction of the possible range of (37)Ar activity concentrations. The influence of soil water content on (37)Ar production is shown to be negligible to first order, while (37)Ar activity concentration in soil gas and its temporal variability appear to be strongly influenced by transient water infiltration events. These results will be used as a basis for practical CTBTO concepts of operation during an OSI. PMID:26939033

  16. Animal-Assisted Activities for Students with Disabilities: Obtaining Stakeholders' Approval and Planning Strategies for Teachers

    ERIC Educational Resources Information Center

    Baumgartner, Erin; Cho, Jeong-il

    2014-01-01

    Animal-human interactions have been found to have positive influences on children across the world. In particular, research supports the benefits of animal-assisted activities in addressing students' social and behavioral problems within the classroom environment. The general information about animal-assisted activities provided in this…

  17. Let's Get Physical: K-12 Students Using Wearable Devices to Obtain and Learn about Data from Physical Activities

    ERIC Educational Resources Information Center

    Lee, Victor R.; Drake, Joel; Williamson, Kylie

    2015-01-01

    Accessibility to wearable technology has exploded in the last decade. As such, this technology has potential to be used in classrooms in uniquely interactive and personally meaningful ways. Seeing this as a possible future for schools, we have been exploring approaches for designing activities to incorporate wearable physical activity data…

  18. PVDF-HFP/ether-modified polysiloxane membranes obtained via airbrush spraying as active separators for application in lithium ion batteries.

    PubMed

    Seidel, S M; Jeschke, S; Vettikuzha, P; Wiemhöfer, H-D

    2015-08-01

    Improved hybrid polymer electrolyte membranes are introduced based on ether-modified polysiloxanes and poly(vinylidene fluoride-co-hexafluoropropylene) yielding a safe separator membrane, which is able to be sprayed directly onto lithium ion battery active materials, with an active role for enhanced ion transport.

  19. Comparison of the expression, activity, and fecal concentration of intestinal alkaline phosphatase between healthy dogs and dogs with chronic enteropathy.

    PubMed

    Ide, Kaori; Kato, Kazuki; Sawa, Yuki; Hayashi, Akiko; Takizawa, Rei; Nishifuji, Koji

    2016-07-01

    OBJECTIVE To compare expression, activity, and fecal concentration of intestinal alkaline phosphatase (IAP) between healthy dogs and dogs with chronic enteropathy (CE). ANIMALS 9 healthy university-owned Beagles and 109 healthy client-owned dogs (controls) and 28 dogs with CE (cases). PROCEDURES Cases were defined as dogs with persistent (> 3 weeks) gastrointestinal signs that failed to respond to antimicrobials and anti-inflammatory doses of prednisolone or dietary trials, did not have mechanical gastrointestinal abnormalities as determined by abdominal radiography and ultrasonography, and had a diagnosis of lymphoplasmacytic enteritis or eosinophilic gastroenteritis on histologic examination of biopsy specimens. Duodenal and colonic mucosa biopsy specimens were obtained from the 9 university-owned Beagles and all cases for histologic examination and determination of IAP expression (by real-time quantitative PCR assay) and activity (by enzyme histochemical analysis). Fecal samples were obtained from all dogs for determination of fecal IAP concentration by a quantitative enzyme reaction assay. RESULTS For dogs evaluated, IAP expression and activity were localized at the luminal side of epithelial cells in the mucosa and intestinal crypts, although both were greater in the duodenum than in the colon. Active IAP was detected in the feces of all dogs. Intestinal alkaline phosphatase expression and activity were lower for cases than for controls, and fecal IAP concentration for dogs with moderate and severe CE was lower than that for dogs with mild CE. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CE had impaired IAP expression and activity. Additional research is necessary to elucidate the role of IAP in the pathogenesis of CE. PMID:27347825

  20. The activity concentrations of 222Rn and corresponding health risk in groundwater samples from basement and sandstone aquifer; the correlation to physicochemical parameters

    NASA Astrophysics Data System (ADS)

    Abdurabu, Wedad Ali; Ramli, Ahmad Termizi; Saleh, Muneer Aziz; Heryansyah, Arien

    2016-10-01

    This study aims to evaluate the activity concentrations of 222Rn and to assess the corresponding health risk in groundwater samples obtained in Juban District, Ad Dali' Governorate, Yemen. The measurements were performed by RAD 7 radon detector manufactured by DURRIDGE COMPANY Inc. The activity concentrations of 222Rn ranged from 1.0±0.2 Bq l-1 to 896.0±0.8 Bq l-1. 57% of the groundwater samples were above the US Environmental Protection Agency (USEPA) recommended value for Rn in water. Induced coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of uranium in groundwater samples. The measured concentration of U ranged from 0.33±0.01 μg l-1 to 24.6±0.6 μg l-1. The results were comparable to internationally recommended values. The highest concentration of U and 222Rn were found to be in the basement aquifer, while the lowest concentrations of both radionuclides were in the sandstone aquifer. High concentrations of Rn are found along fault zones. The relationship between the activity concentration of 222Rn, concentration of U and physicochemical parameters were investigated. The results showed a very strong relationship between activity concentrations of 222Rn with concentrations of U and the salinity of water.

  1. Sedentary behavior, physical activity, and concentrations of insulin among US adults.

    PubMed

    Ford, Earl S; Li, Chaoyang; Zhao, Guixiang; Pearson, William S; Tsai, James; Churilla, James R

    2010-09-01

    Time spent watching television has been linked to obesity, metabolic syndrome, and diabetes, all conditions characterized to some degree by hyperinsulinemia and insulin resistance. However, limited evidence relates screen time (watching television or using a computer) directly to concentrations of insulin. We examined the cross-sectional associations between time spent watching television or using a computer, physical activity, and serum concentrations of insulin using data from 2800 participants aged at least 20 years of the 2003-2006 National Health and Nutrition Examination Survey. The amount of time spent watching television and using a computer as well as physical activity was self-reported. The unadjusted geometric mean concentration of insulin increased from 6.2 microU/mL among participants who did not watch television to 10.0 microU/mL among those who watched television for 5 or more hours per day (P = .001). After adjustment for age, sex, race or ethnicity, educational status, concentration of cotinine, alcohol intake, physical activity, waist circumference, and body mass index using multiple linear regression analysis, the log-transformed concentrations of insulin were significantly and positively associated with time spent watching television (P = < .001). Reported time spent using a computer was significantly associated with log-transformed concentrations of insulin before but not after accounting for waist circumference and body mass index. Leisure-time physical activity but not transportation or household physical activity was significantly and inversely associated with log-transformed concentrations of insulin. Sedentary behavior, particularly the amount of time spent watching television, may be an important modifiable determinant of concentrations of insulin.

  2. Chemical composition and anti-Trypanosoma cruzi activity of essential oils obtained from leaves of Xylopia frutescens and X. laevigata (Annonaceae).

    PubMed

    da Silva, Thanany Brasil; Menezes, Leociley Rocha Alencar; Sampaio, Marília Fernanda Chaves; Meira, Cássio Santana; Guimarães, Elisalva Teixeira; Soares, Milena Botelho Pereira; Prata, Ana Paula do Nascimento; Nogueira, Paulo Cesar de Lima; Costa, Emmanoel Vilaça

    2013-03-01

    Essential oils from leaves of Xylopia frutescens (XFMJ) and two specimens of Xylopia laevigata (XLMC and XLSI) were obtained by hydrodistillation using a Clevenger-type apparatus, and analyzed by GC-MS and GC-FID. Sesquiterpenes dominated the essential oils. The main constituents of XFMJ were (E)-caryophyllene (24.8%), bicyclogermacrene (20.8%), germacrene D (17.0%), beta-elemene (7.9%), and (E)-beta-ocimene (6.8%). XLMC contained significant quantities of germacrene D (18.9%), bicyclogermacrene (18.4%), beta-elemene (9.5%), delta-selinene (9.2%), (E)-caryophyllene (8.5%), germacrene B (5.7%) and gamma-muurolene (5.7%), while germacrene D (27.0%), bicyclogermacrene (12.8%), (E)-caryophyllene (8.6%), gamma-muurolene (8.6%), delta-cadinene (6.8%), and germacrene B (6.0%) were the main components of XLSI. The essential oils had trypanocidal activity against the Y strain of Trypanosoma cruzi, with IC50 values lower than 30 microg x mL(-1) and 15 microg x mL(-1) against epimastigote and trypomastigote forms of T. cruzi, respectively, and were also able to reduce the percentage in vitro of T. cruzi-infected macrophages and the intracellular number of amastigotes at concentrations that were non-cytotoxic to macrophages.

  3. Transformation of organic-inorganic hybrid films obtained by molecular layer deposition to photocatalytic layers with enhanced activity.

    PubMed

    Ishchuk, Sergey; Taffa, Dereje Hailu; Hazut, Ori; Kaynan, Niv; Yerushalmi, Roie

    2012-08-28

    We present the transformation of organic-inorganic hybrid titanicone films formed by TiCl(4) as metal precursor and ethylene glycol (EG) using solvent-free MLD to highly active photocatalytic films. The photocatalytic activities of the films were investigated using hydroxyl-functionalized porphyrin as a spectroscopic marker. TEM imaging and electron diffraction, XPS, UV-vis spectroscopy, and spectroscsopic ellipsometry were employed for structural and composition analyses of the films. The photocatalytic activity of Ti-EG films was investigated for different anneal temperatures and compared to TiO(2) films prepared by ALD using TiCl(4) as metal precursor and H(2)O (TiO(2) films). Overall, our results indicate that the photocatalytic activity of the thermally annealed Ti-EG film is about 5-fold increased compared to that of the TiO(2) film prepared by ALD for optimal process conditions. The combined results indicate that the structural and photocatalytic properties can be assigned to three states: (I) amorphous state, intermediate dye loading, low photocatalytic activity, (II) intermediate film state with both crystalline and amorphous regions, high dye loading, high catalytic activity, and (III) highly crystalline film with low dye loading and low photocatalytic activity. The formation of photocatalytic nanotubes (NTs) is demonstrated using sacrificial Ge nanowires (NWs) scaffolds to yield Ti-EG NT structures with controllable wall thickness structures and enhanced dye loading capacity. Our results demonstrate the feasibility and high potential of MLD to form metal oxides with high photocatalytic activity. PMID:22768917

  4. Relationship between Salivary Alkaline Phosphatase Enzyme Activity and The Concentrations of Salivary Calcium and Phosphate Ions

    PubMed Central

    Jazaeri, Mina; Malekzadeh, Hosein; Abdolsamadi, Hamidreza; Rezaei-Soufi, Loghman; Samami, Mohammad

    2015-01-01

    Although salivary alkaline phosphatase (ALP) can balance deand remineralization processes of enamel, there is no evidence regarding its effects on the concentrations of calcium and phosphate in saliva. The present study aims to determine the relationship between salivary ALP activity and the concentrations of calcium and phosphate in saliva. In this cross-sectional study, we evaluated salivary markers in 120 males, ages 19 to 44 years. All participants provided 5 mL of unstimulated whole saliva and the level of enzyme activity as well as calcium and phosphate concentrations were measured using a colorimetric method. Data were gathered and analyzed by statistical package for social sciences (SPSS) 13.00 using Pearson correlation test. A p value of <0.05 was considered statistically significant. The mean age of participants in the present study was 32.95 ± 8.09 years. The mean pH of saliva was 6.65 ± 0.62. Salivary parameters included average ALP activity (5.04 ± 1.866 U/dL), calcium (4.77 ± 0.877 mg/dL) and phosphate (10.38 ± 2.301 mg/dL). Pearson correlation test showed no significant relationship between ALP activity and calcium and phosphate concentrations in saliva (p>0.05). According to the results of the present study, there was no significant relation between salivary ALP activity and calcium and phosphate concentrations in saliva. However, further research is highly recommended. PMID:25870846

  5. Brain activation in response to randomized visual stimulation as obtained from conjunction and differential analysis: an fMRI study

    NASA Astrophysics Data System (ADS)

    Nasaruddin, N. H.; Yusoff, A. N.; Kaur, S.

    2014-11-01

    The objective of this multiple-subjects functional magnetic resonance imaging (fMRI) study was to identify the common brain areas that are activated when viewing black-and-white checkerboard pattern stimuli of various shapes, pattern and size and to investigate specific brain areas that are involved in processing static and moving visual stimuli. Sixteen participants viewed the moving (expanding ring, rotating wedge, flipping hour glass and bowtie and arc quadrant) and static (full checkerboard) stimuli during an fMRI scan. All stimuli have black-and-white checkerboard pattern. Statistical parametric mapping (SPM) was used in generating brain activation. Differential analyses were implemented to separately search for areas involved in processing static and moving stimuli. In general, the stimuli of various shapes, pattern and size activated multiple brain areas mostly in the left hemisphere. The activation in the right middle temporal gyrus (MTG) was found to be significantly higher in processing moving visual stimuli as compared to static stimulus. In contrast, the activation in the left calcarine sulcus and left lingual gyrus were significantly higher for static stimulus as compared to moving stimuli. Visual stimulation of various shapes, pattern and size used in this study indicated left lateralization of activation. The involvement of the right MTG in processing moving visual information was evident from differential analysis, while the left calcarine sulcus and left lingual gyrus are the areas that are involved in the processing of static visual stimulus.

  6. Telomerase activity concentrates in the mitotically active segments of human hair follicles.

    PubMed

    Ramirez, R D; Wright, W E; Shay, J W; Taylor, R S

    1997-01-01

    Telomerase is a ribonucleoprotein enzyme capable of adding hexanucleotide repeats onto the ends of linear chromosomal DNA. Whereas normal somatic cells with a limited replicative capacity fail to express telomerase activity, most immortal eukaryotic cells do. Cells of renewal tissues (e.g., skin, intestine, blood) require an extensive proliferative capacity. Some cells in such renewal tissues also express telomerase activity, most likely to prevent rapid erosion of their telomeres during cell proliferation. In this study, we measured the levels of telomerase activity in dissected compartments of the human hair follicle: hair shaft, gland-containing fragment, upper intermediate fragment (where it is thought undifferentiated stem cells reside), lower intermediate fragment, and in the bulb-containing fragment (an area with high mitotic activity containing a more differentiated pool of keratinocytes). In anagen follicles, high levels of telomerase activity were found almost exclusively in the bulb-containing fragment of the follicles, with low levels of telomerase in the bulge area (intermediate fragments) and gland-containing fragment. In comparison, catagen follicles had low levels of telomerase activity in the bulb-containing fragments as well as in other compartments. Such observations indicate that, in anagen hair follicles, the fragments containing cells actively dividing (e.g., transient amplifying cells) express telomerase activity, whereas fragments containing cells with low mitotic activity, for example, quiescent stem cells, express low levels of telomerase activity. PMID:8980299

  7. Metabolic pathways and activity-dependent modulation of glutamate concentration in the human brain.

    PubMed

    Mangia, Silvia; Giove, Federico; Dinuzzo, Mauro

    2012-11-01

    Glutamate is one of the most versatile molecules present in the human brain, involved in protein synthesis, energy production, ammonia detoxification, and transport of reducing equivalents. Aside from these critical metabolic roles, glutamate plays a major part in brain function, being not only the most abundant excitatory neurotransmitter, but also the precursor for γ-aminobutyric acid, the predominant inhibitory neurotransmitter. Regulation of glutamate levels is pivotal for normal brain function, as abnormal extracellular concentration of glutamate can lead to impaired neurotransmission, neurodegeneration and even neuronal death. Understanding how the neuron-astrocyte functional and metabolic interactions modulate glutamate concentration during different activation status and under physiological and pathological conditions is a challenging task, and can only be tentatively estimated from current literature. In this paper, we focus on describing the various metabolic pathways which potentially affect glutamate concentration in the brain, and emphasize which ones are likely to produce the variations in glutamate concentration observed during enhanced neuronal activity in human studies.

  8. Fusion of satellite active and passive microwave data for sea ice type concentration estimates

    SciTech Connect

    Beaven, S.G.; Gogineni, S.; Carsey, F.D.

    1996-09-01

    Young first-year sea ice is nearly as important as open water in modulating heat flux between the ocean and atmosphere in the Arctic. Just after the onset of freeze-up, first-year ice is in the early stages of growth and will consist of young first-year and thin ice. The distribution of sea ice in this thickness range impacts heat transfer in the Arctic. Therefore, improving the estimates of ice concentrations in this thickness range is significant. NASA Team Algorithm (NTA) for passive microwave data inaccurately classifies sea ice during the melt and freeze-up seasons because it misclassifies multiyear ice as first-year ice. The authors developed a hybrid fusion technique for incorporating multiyear ice information derived form synthetic aperture radar (SAR) images into a passive microwave algorithm to improve ice type concentration estimates. First, they classified SAR images using a dynamic thresholding technique and estimated the multiyear ice concentration. Then they used the SAR-derived multiyear ice concentration constrain the NTA and obtained an improved first-year ice concentration estimate. They computed multiyear and first-year ice concentration estimates over a region in the eastern-central Arctic in which field observations of ice and in situ radar backscatter measurements were performed. With the NTA alone, the first-year ice concentration in the study area varied between 0.11 and 0.40, while the multiyear ice concentration varied form 0.63 to 0.39. With the hybrid fusion technique, the first-year ice concentration varied between 0.08 and 0.23 and the multiyear ice concentration was between 0.62 and 0.66. The fused estimates of first-year and multiyear ice concentration appear to be more accurate than NTA, based on ice observations that were logged aboard the US Coast Guard icebreaker Polar Star in the study area during 1991.

  9. Selenium status, lipid peroxides concentration, and glutathione peroxidase activity in the blood of power station and rubber factory workers.

    PubMed

    Zachara, B A; Wasowicz, W; Sklodowska, M; Gromadzinska, J

    1987-01-01

    Concentration of selenium in whole blood and plasma, lipid peroxides in plasma, and glutathione peroxidase activities in red blood cell hemolysates and plasma were determined in 49 coal power plant workers and in 50 rubber factory workers. The results were compared with those obtained for 58 nonindustrial controls. Whole blood selenium was significantly lower and plasma lipid peroxides were significantly higher in power plant workers when compared to the nonindustrial group. In the rubber factory workers, whole blood selenium and red blood cells and plasma glutathione peroxidase activities were significantly lower than in the control group. Urinary output of selenium was also significantly decreased in rubber factory workers. Slightly elevated lipid peroxides were also observed in that group. It seems reasonable to conclude that the lower blood selenium and decreased urinary output of this element may result from increased loss of selenium with perspiration. No correlation has been observed between selenium concentration and glutathione peroxidase activity and between enzyme activity and lipid peroxides concentration in the industrial group.

  10. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    USGS Publications Warehouse

    Franson, J.C.; Hoffman, D.J.; Schmutz, J.A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathera??molting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  11. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    USGS Publications Warehouse

    Franson, J.C.; Hoffman, D.J.; Schmutz, J.A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathermolting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  12. Evaluation of antioxidant activities of bioactive compounds and various extracts obtained from saffron (Crocus sativus L.): a review.

    PubMed

    Rahaiee, Somayeh; Moini, Sohrab; Hashemi, Maryam; Shojaosadati, Seyed Abbas

    2015-04-01

    Saffron (Crocus sativus L. stigma), the most valuable medicinal food product, belongs to the Iridaceae family which has been widely used as a coloring and flavoring agent. These properties are basically related to its crocins, picrocrocin and safranal contents which have all demonstrated health promoting properties. The present review article highlights the phytochemical constituents (phenolic and flavonoid compounds, degraded carotenoid compounds crocins and crocetin) that are important in antioxidant activity of saffron extracts. However, the synergistic effect of all the bioactive components presence in saffron gave a significant antioxidant activity similar to vegetables rich in carotenoids. Our study provides an updated overview focused on the antioxidant activity of saffron related to its bioactive compounds to design the different functional products in food, medicine and cosmetic industries.

  13. Angiotensin I-Converting Enzyme (ACE) Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar) Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    PubMed Central

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E.; Minkiewicz, Piotr; Iwaniak, Anna

    2014-01-01

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes. PMID:25123137

  14. Angiotensin I-converting enzyme (ACE) inhibitory activity and ACE inhibitory peptides of salmon (Salmo salar) protein hydrolysates obtained by human and porcine gastrointestinal enzymes.

    PubMed

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E; Minkiewicz, Piotr; Iwaniak, Anna

    2014-08-13

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  15. Intramuscular pressure and torque during isometric, concentric and eccentric muscular activity

    NASA Technical Reports Server (NTRS)

    Styf, J.; Ballard, R.; Aratow, M.; Crenshaw, A.; Watenpaugh, D.; Hargens, A. R.

    1995-01-01

    Intramuscular pressures, electromyography (EMG) and torque generation during isometric, concentric and eccentric maximal isokinetic muscle activity were recorded in 10 healthy volunteers. Pressure and EMG activity were continuously and simultaneously measured side by side in the tibialis anterior and soleus muscles. Ankle joint torque and position were monitored continuously by an isokinetic dynamometer during plantar flexion and dorsiflexion of the foot. The increased force generation during eccentric muscular activity, compared with other muscular activity, was not accompanied by higher intramuscular pressure. Thus, this study demonstrated that eccentric muscular activity generated higher torque values for each increment of intramuscular pressure. Intramuscular pressures during antagonistic co-activation were significantly higher in the tibilis anterior muscle (42-46% of maximal agonistic activity) compared with the soleus muscle (12-29% of maximal agonistic activity) and was largely due to active recruitment of muscle fibers. In summary, eccentric muscular activity creates higher torque values with no additional increase of the intramuscular pressure compared with concentric and isometric muscular activity.

  16. Antifungal, anti-inflammatory and cytotoxicity activities of three varieties of labisia pumila benth: from microwave obtained extracts

    PubMed Central

    2013-01-01

    Background Labisia pumila, locally known as Kacip Fatimah, is a forest-floor plant that has tremendous potential in the herbal industry. It is one of the five herbal plants identified by the government as one of the national key economic areas to be developed for commercial purposes. There are three varieties of L. pumila namely, L. pumila var. pumila, L. pumila var. alata and L. pumila var. lanceolata and each has its own use. Methods The leaves and roots of the three varieties of L. pumila Benth. were extracted using microwave assisted extraction (MAE). Antifungal activity of all plant extracts were characterized against Fusarium sp., Candida sp. and Mucor using the agar diffusion disc. Anti-inflammatory assays were performed using NO production by macrophage RAW 264.7 cell lines induced by LPS/IFN-g and cytotoxic activity was determined using several cancer cell lines and one normal cell line. Results The overall result demonstrated that leaf and root extracts of all three varieties of L. pumila exhibited moderate to appreciable antifungal activity against Fusarium sp., Candida sp. and Mucor compared to streptomycin used as positive control. Leaf and root extracts of all varieties significantly decreased NO release. However, the root extracts showed higher activity compared to the leaf extracts. Cytotoxic activity against MCF-7, MDA-MB-231 and Chang cell lines were observed with all extracts. Conclusions These findings suggest the potential use of L. pumila Benth. as a natural medicine and indicated the possible application of this medicinal plant such anti inflammatory activity and cytotoxic agents. PMID:23347830

  17. Magnetic Tilts in Sunspot Groups and Active regions in the Cycle 23 obtained from the Solar Feature Catalogues

    NASA Astrophysics Data System (ADS)

    Zharkov, S. I.; Zharkova, V. V.; Bianda, M.; Cartesi, S.

    We compare a few methods for calculation of magnetic tilts in active regions using using the automated sunspot group classification from the Solar Feature Catalogues http solar inf brad ac uk for 1996-2005 The best performing methods were applied to investigate the statistical variations of magnetic field tilt in sunspot groups and their relation to the total magnetic field contained in sunspots during different phases of the solar cycle 23 The classification results are compared with the similar research for the cycle 22 and the specifics on the cycle 23 is discussed The results are also tested against the existing solar dynamo models and their applicability for the solar activity forecast

  18. Activated sludge pilot plant: comparison between experimental and predicted concentration profiles using three different modelling approaches.

    PubMed

    Le Moullec, Y; Potier, O; Gentric, C; Leclerc, J P

    2011-05-01

    This paper presents an experimental and numerical study of an activated sludge channel pilot plant. Concentration profiles of oxygen, COD, NO(3) and NH(4) have been measured for several operating conditions. These profiles have been compared to the simulated ones with three different modelling approaches, namely a systemic approach, CFD and compartmental modelling. For these three approaches, the kinetics model was the ASM-1 model (Henze et al., 2001). The three approaches allowed a reasonable simulation of all the concentration profiles except for ammonium for which the simulations results were far from the experimental ones. The analysis of the results showed that the role of the kinetics model is of primary importance for the prediction of activated sludge reactors performance. The fact that existing kinetics parameters in the literature have been determined by parametric optimisation using a systemic model limits the reliability of the prediction of local concentrations and of the local design of activated sludge reactors. PMID:21489593

  19. Polychlorinated biphenyl concentrations and activity of sea lamprey Petromyzon marinus vary by sex.

    PubMed

    Madenjian, C P; Johnson, N S; Binder, T R; Rediske, R R; O'Keefe, J P

    2013-11-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native. PMID:23864162

  20. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Binder, Thomas R.; Rediske, Richard R.; O'Keefe, James P.

    2013-01-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native.

  1. Indoor radon activity concentration measurements in the great historical museums of University of Naples, Italy.

    PubMed

    Quarto, Maria; Pugliese, Mariagabriella; Loffredo, Filomena; La Verde, Giuseppe; Roca, Vincenzo

    2016-01-01

    Indoor radon activity concentrations were measured in seven Museums of University of Naples, very old buildings of great historical value. The measurements were performed using a time-integrated technique based on LR-115 solid-state nuclear track detectors. The annual average concentrations were found to range from 40 up to 1935 Bq m(-3) and in 26 % of measurement sites, the values were higher than 500 Bq m(-3) which is the limit value of Italian legislation for workplace. Moreover, we analysed the seasonal variations of radon concentrations observing the highest average in cold weather than in warm.

  2. The effect of concentration- and temperature-dependent dielectric constant on the activity coefficient of NaCl electrolyte solutions

    SciTech Connect

    Valiskó, Mónika; Boda, Dezső

    2014-06-21

    Our implicit-solvent model for the estimation of the excess chemical potential (or, equivalently, the activity coefficient) of electrolytes is based on using a dielectric constant that depends on the thermodynamic state, namely, the temperature and concentration of the electrolyte, ε(c, T). As a consequence, the excess chemical potential is split into two terms corresponding to ion-ion (II) and ion-water (IW) interactions. The II term is obtained from computer simulation using the Primitive Model of electrolytes, while the IW term is estimated from the Born treatment. In our previous work [J. Vincze, M. Valiskó, and D. Boda, “The nonmonotonic concentration dependence of the mean activity coefficient of electrolytes is a result of a balance between solvation and ion-ion correlations,” J. Chem. Phys. 133, 154507 (2010)], we showed that the nonmonotonic concentration dependence of the activity coefficient can be reproduced qualitatively with this II+IW model without using any adjustable parameter. The Pauling radii were used in the calculation of the II term, while experimental solvation free energies were used in the calculation of the IW term. In this work, we analyze the effect of the parameters (dielectric constant, ionic radii, solvation free energy) on the concentration and temperature dependence of the mean activity coefficient of NaCl. We conclude that the II+IW model can explain the experimental behavior using a concentration-dependent dielectric constant and that we do not need the artificial concept of “solvated ionic radius” assumed by earlier studies.

  3. The effect of concentration- and temperature-dependent dielectric constant on the activity coefficient of NaCl electrolyte solutions.

    PubMed

    Valiskó, Mónika; Boda, Dezső

    2014-06-21

    Our implicit-solvent model for the estimation of the excess chemical potential (or, equivalently, the activity coefficient) of electrolytes is based on using a dielectric constant that depends on the thermodynamic state, namely, the temperature and concentration of the electrolyte, ε(c, T). As a consequence, the excess chemical potential is split into two terms corresponding to ion-ion (II) and ion-water (IW) interactions. The II term is obtained from computer simulation using the Primitive Model of electrolytes, while the IW term is estimated from the Born treatment. In our previous work [J. Vincze, M. Valiskó, and D. Boda, "The nonmonotonic concentration dependence of the mean activity coefficient of electrolytes is a result of a balance between solvation and ion-ion correlations," J. Chem. Phys. 133, 154507 (2010)], we showed that the nonmonotonic concentration dependence of the activity coefficient can be reproduced qualitatively with this II+IW model without using any adjustable parameter. The Pauling radii were used in the calculation of the II term, while experimental solvation free energies were used in the calculation of the IW term. In this work, we analyze the effect of the parameters (dielectric constant, ionic radii, solvation free energy) on the concentration and temperature dependence of the mean activity coefficient of NaCl. We conclude that the II+IW model can explain the experimental behavior using a concentration-dependent dielectric constant and that we do not need the artificial concept of "solvated ionic radius" assumed by earlier studies.

  4. Influence of microwave irradiation on boron concentrate activation with an emphasis on surface properties

    NASA Astrophysics Data System (ADS)

    Jiang, Tao; Zhang, Qiaoyi; Liu, Yajing; Xue, Xiangxin; Duan, Peining

    2016-11-01

    In this study, we employed microwave irradiation for activating boron concentrate, an abundant but low-grade boron mineral resource in China. The boron concentrate was pretreated by microwave irradiation based on TG-DTG-DSC analysis, and the influence of each parameter on processing efficiency was characterized using chemical analysis, XRD, SEM, FTIR and particle distribution analysis. Subsequently, the surface properties of boron concentrate and the mechanism of microwave irradiation was analyzed. Our results indicate that microwave irradiation decreased the processing temperature and shortened the roasting time by accelerating dehydroxylation and oxidation reactions in the boron concentrate, reducing the particle diameter and damaging the microstructure of the minerals, and it increased the B2O3 activity of boron from 64.68% to 86.73%, greater than the optimal conventional treatment. Compared with the simple thermal field, microwave roasting obviously increased ability of the boron concentrate to absorb OH- in the leachant and promoted boron leaching by expanding the contact area of the mineral exposed to leachant, boosting the amount of Mg2+ and Fe3+ on mineral surfaces, and increasing the hydrophilicity of the boron concentrate respectively. It enhanced the γSVLW and γSV- of boron concentrate from 29.15 mJ/m2 and 5.07 mJ/m2 to 37.07 mJ/m2 and 12.41 mJ/m2.

  5. User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part I, Deployment, recovery, data interpretation, and quality control and assurance

    USGS Publications Warehouse

    Vroblesky, Don A.

    2001-01-01

    Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

  6. Receptor Binding Sites for Substance P, but not Substance K or Neuromedin K, are Expressed in High Concentrations by Arterioles, Venules, and Lymph Nodules in Surgical Specimens Obtained from Patients with Ulcerative Colitis and Crohn Disease

    NASA Astrophysics Data System (ADS)

    Mantyh, Christopher R.; Gates, Troy S.; Zimmerman, Robert P.; Welton, Mark L.; Passaro, Edward P.; Vigna, Steven R.; Maggio, John E.; Kruger, Lawrence; Mantyh, Patrick W.

    1988-05-01

    Several lines of evidence indicate that tachykinin neuropeptides [substance P (SP), substance K (SK), and neuromedin K (NK)] play a role in regulating the inflammatory and immune responses. To test this hypothesis in a human inflammatory disease, quantitative receptor autoradiography was used to examine possible abnormalities in tachykinin binding sites in surgical specimens from patients with inflammatory bowel disease. Surgical specimens of colon were obtained from patients with ulcerative colitis (n = 4) and Crohn disease (n = 4). Normal tissue was obtained from uninvolved areas of extensive resections for carcinoma (n = 6). In all cases, specimens were obtained <5 min after removal to minimize influences associated with degradation artifacts and were processed for quantitative receptor autoradiography by using 125I-labeled Bolton--Hunter conjugates of NK, SK, and SP. In the normal colon a low concentration of SP receptor binding sites is expressed by submucosal arterioles and venules and a moderate concentration is expressed by the external circular muscle, whereas SK receptor binding sites are expressed in low concentrations by the external circular and longitudinal muscle. In contrast, specific NK binding sites were not observed in any area of the human colon. In colon tissue obtained from ulcerative colitis and Crohn disease patients, however, very high concentrations of SP receptor binding sites are expressed by arterioles and venules located in the submucosa, muscularis mucosa, external circular muscle, external longitudinal muscle, and serosa. In addition, very high concentrations of SP receptor binding sites are expressed within the germinal center of lymph nodules, whereas the concentrations of SP and SK binding sites expressed by the external muscle layers are not altered significantly. These results demonstrate that receptor binding sites for SP, but not SK or NK, are ectopically expressed in high concentrations (1000-2000 times normal) by cells

  7. Antioxidant activity measured in different solvent fractions obtained from Mentha spicata Linn.: an analysis by ABTS*+ decolorization assay.

    PubMed

    Arumugam, Ponnan; Ramamurthy, Perumal; Santhiya, Sathiyavedu Thyagarajan; Ramesh, Arabandi

    2006-01-01

    Antioxidant compounds are abundantly available in plants and play an important role in scavenging free radicals, thus providing protection to humans against oxidative DNA damage. Mentha spicata Linn., commonly called spearmint, belongs to the family lamiaceae. It was selected in the present study because Mentha extracts have antioxidant properties due to the presence of eugenol, caffeic acid, rosmarinic acid and alpha-tocopherol. Four solvent fractions (hexane, chloroform, ethyl acetate and water) of ethanolic extract of dried leaves powder of M. spicata were analyzed for total antioxidant activity (TAA) and relative antioxidant activity (RAA) and compared with standard antioxidants such as Quercetin, beta-carotene, L-ascorbic acid and glutathione using ABTS*+ decolorization assay (ABTS/Potassium persulphate). The antioxidant activity was assumed to be from the total phenolic content of the ethanolic extract. Total phenolics are found to be highest in ethyl acetate fraction (54 mg/g) and least in hexane fraction (13 mg/g) and more or less similar in water and chloroform fractions (30-32 mg/g). TAA is found to be less in hexane and chloroform fractions (<53% at 50 microg/ml) and highest in ethyl acetate (95% at 20 microg/ml) and water (84% at 30 microg/ml) fractions. The RAA of ethyl acetate fraction is 1.1 compared to quercetin (at 5 microM/ml), but greater when compared to beta-carotene (15 microM/ml), L-ascorbic acid (15 microM/ml) and glutathione (15 microM/ml). The RAAs with these antioxidants are in the range of 1.31 -1.6. The values of RAAs for water fraction also show similar trend and are in the range of 1.0-1.4. The antioxidant activities of the solvent factions are closely related to the content of total phenolics present in them.

  8. Preliminary results, obtained by using a proton beam, for an active scanning system to installed on the KHIMA

    NASA Astrophysics Data System (ADS)

    Kim, Chang Hyeuk; Lee, Hwa-Ryun; Jang, Sea Duk; Kim, Hyunyong; Hahn, Garam; Kim, Jeong Hwan; Jang, Hong Suk; Park, Dong Wook; Hwang, Won Taek; Yang, Tae-Keun

    2015-08-01

    The active scanning technique is a pencil beam delivery method in particle therapy. The active scanning beam delivery system consists of a beam scanner, beam monitor, energy modulator, and related programs, such as the irradiation control and planning programs. A proposed prototype active scanning system was designed and installed on MC-50 at the Korea Institute of Radiological and Medical Science (KIRAMS) with a 45-MeV proton beam. The laminated magnetic yoke of the scanning magnet supported fast ramping. The beam intensity and the beam profile monitors were designed for measuring the beam's properties. Both the range shifter and the ridge filter modulate the incoming beam energy. The LabVIEW®-based beam-irradiation-control program operates the system in a sequential operation manner for use with the MC-50 cyclotron. In addition, an in-housecoded irradiation-planning program generates an optimal irradiation path. A scanning experiment was successfully completed to print the logo of the Korea Heavy Ion Medical Accelerator (KHIMA) on GaF film. Moreover, the beam's position accuracy was measured as 0.62 mm in the x-direction and as 0.83 mm in the y-direction.

  9. Antioxidant activity and total phenolic compounds of Dezful sesame cake extracts obtained by classical and ultrasound-assisted extraction methods

    PubMed Central

    Esmaeilzadeh Kenari, Reza; Mohsenzadeh, Fatereh; Amiri, Zeinab Raftani

    2014-01-01

    Sesame cake is a by-product of sesame oil industry. In this study, the effect of extraction methods (maceration and sonication) and solvents (ethanol, methanol, ethanol/water (50:50), methanol/water (50:50), and water) on the antioxidant properties of sesame cake extracts are evaluated to determine the most suitable extraction method for optimal use of this product. Total phenolic content is measured according to the Folin–Ciocalteu method and antioxidant activities of each extract are evaluated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching, and ferric reducing/antioxidant power (FRAP) methods. The highest amount of total phenolic compounds is observed in ethanol-ultrasonic extract with the amount of 88.89 mg/g gallic acid equivalent. Methanol-ultrasonic extract with the amount of 88.475% indicates the highest activity in scavenging DPPH free radicals. In β-carotene-linoleic acid system, ethanol-ultrasonic extract indicates the highest inhibition percent of 45.64. In FRAP assay, ethanol/water (50:50)-maceration and ethanol/water (50:50)-ultrasonic extracts with the absorption of 1.132 and 1.0745 nm indicate the highest antioxidant activity. PMID:25473500

  10. Preparation of factor VII concentrate using CNBr-activated Sepharose 4B immunoaffinity chromatography

    PubMed Central

    Mousavi Hosseini, Kamran; Nasiri, Saleh

    2015-01-01

    Background: Factor VII concentrates are used in patients with congenital or acquired factor VII deficiency or treatment of hemophilia patients with inhibitors. In this research, immunoaffinity chromatography was used to purify factor VII from prothrombin complex (Prothrombin- Proconvertin-Stuart Factor-Antihemophilic Factor B or PPSB) which contains coagulation factors II, VII, IX and X. The aim of this study was to improve purity, safety and tolerability as a highly purified factor VII concentrate. Methods: PPSB was prepared using DEAE-Sephadex and was used as the starting material for purification of coagulation factor VII. Prothrombin complex was treated by solvent/detergent at 24°C for 6 h with constant stirring. The mixture of PPSB in the PBS buffer was filtered and then chromatographed using CNBr-activated Sepharose 4B coupled with specific antibody. Factors II, IX, VII, X and VIIa were assayed on the fractions. Fractions of 48-50 were pooled and lyophilized as a factor VII concentrate. Agarose gel electrophoresis was performed and Tween 80 was measured in the factor VII concentrate. Results: Specific activity of factor VII concentrate increased from 0.16 to 55.6 with a purificationfold of 347.5 and the amount of activated factor VII (FVIIa) was found higher than PPSB (4.4-fold). Results of electrophoresis on agarose gel indicated higher purity of Factor VII compared to PPSB; these finding revealed that factor VII migrated as alpha-2 proteins. In order to improve viral safety, solvent-detergent treatment was applied prior to further purification and nearly complete elimination of tween 80 (2 μg/ml). Conclusion: It was concluded that immuonoaffinity chromatography using CNBr-activated Sepharose 4B can be a suitable choice for large-scale production of factor VII concentrate with higher purity, safety and activated factor VII. PMID:26034723

  11. Concentrated dispersions of equilibrium protein nanoclusters that reversibly dissociate into active monomers

    NASA Astrophysics Data System (ADS)

    Truskett, Thomas M.; Johnston, Keith; Maynard, Jennifer; Borwankar, Ameya; Miller, Maria; Wilson, Brian; Dinin, Aileen; Khan, Tarik; Kaczorowski, Kevin

    2012-02-01

    Stabilizing concentrated protein solutions is of wide interest in drug delivery. However, a major challenge is how to reliably formulate concentrated, low viscosity (i.e., syringeable) solutions of biologically active proteins. Unfortunately, proteins typically undergo irreversible aggregation at intermediate concentrations of 100-200 mg/ml. In this talk, I describe how they can effectively avoid these intermediate concentrations by reversibly assembling into nanoclusters. Nanocluster assembly is achieved by balancing short-ranged, cosolute-induced attractions with weak, longer-ranger electrostatic repulsions near the isoelectric point. Theory predicts that native proteins are stabilized by a self-crowding mechanism within the concentrated environment of the nanoclusters, while weak cluster-cluster interactions can result in colloidally-stable dispersions with moderate viscosities. I present experimental results where this strategy is used to create concentrated antibody dispersions (up to 260 mg/ml) comprising nanoclusters of proteins [monoclonal antibody 1B7, polyclonal sheep Immunoglobin G and bovine serum albumin], which upon dilution in vitro or administration in vivo, are conformationally stable and retain activity.

  12. Relationship between Physical Activity and Plasma Fibrinogen Concentrations in Adults without Chronic Diseases

    PubMed Central

    Gomez-Marcos, Manuel A.; Recio-Rodríguez, José I.; Patino-Alonso, Maria C.; Martinez-Vizcaino, Vicente; Martin-Borras, Carme; de-la-Cal-dela-Fuente, Aventina; Sauras-Llera, Ines; Sanchez-Perez, Alvaro; Agudo-Conde, Cristina; García-Ortiz, Luis

    2014-01-01

    Objective To analyze the relationship between regular physical activity, as assessed by accelerometer and 7-day physical activity recall (PAR), and plasma fibrinogen concentrations. Methods A cross-sectional study in a previously established cohort of healthy subjects was performed. This study analyzed 1284 subjects who were included in the EVIDENT study (mean age 55.0±13.6 years; 60.90% women). Fibrinogen concentrations were measured in blood plasma. Physical activity was assessed with a 7-day PAR (metabolic equivalents (METs)/hour/week) and GT3X ActiGraph accelerometer (counts/minute) for 7 days. Results Physical exercise, which was evaluated with both an accelerometer (Median: 237.28 counts/minute) and 7-day PAR (Median: 8 METs/hour/week). Physical activity was negatively correlated with plasma fibrinogen concentrations, which was evaluated by counts/min (r = −0.100; p<0.001) and METs/hour/week (r = −0.162; p<0.001). In a multiple linear regression analysis, fibrinogen concentrations of the subjects who performed more physical activity (third tertile of count/minute and METs/hour/week) respect to subjects who performed less (first tertile), maintained statistical significance after adjustments for age and others confounders (β = −0.03; p = 0.046 and β = −0.06; p<0.001, respectively). Conclusions Physical activity, as assessed by accelerometer and 7-day PAR, was negatively associated with plasma fibrinogen concentrations. This relation is maintained in subjects who performed more exercise even after adjusting for age and other confounders. PMID:24498413

  13. Antioxidant activities and xanthine oxidase inhibitory effects of extracts and main polyphenolic compounds obtained from Geranium sibiricum L.

    PubMed

    Wu, Nan; Zu, Yuangang; Fu, Yujie; Kong, Yu; Zhao, Jintong; Li, Xiaojuan; Li, Ji; Wink, Michael; Efferth, Thomas

    2010-04-28

    The antioxidant capacity and xanthine oxidase inhibitory effects of extracts and main polyphenolic compounds of Geranium sibiricum were studied in the present work. The antioxidant capacity was evaluated by ferric reducing antioxidant power, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, superoxide radical scavenging, nitric oxide scavenging, beta-carotene-linoleic acid bleaching, and reducing power assays. Among the extracts and four fractions, the ethyl acetate fraction showed the highest phenolic content (425.36 +/- 9.70 mg of gallic acid equivalent/g extracts) and the best antioxidant activity. The IC(50) values of the ethyl acetate fraction were 0.93, 3.32, 2.06, 2.66, and 1.64 microg/mL in the DPPH radical scavenging, superoxide radical scavenging, nitric oxide scavenging, beta-carotene-linoleic acid bleaching, and reducing power assays, respectively. Of the polyphenolic compounds separated from the ethyl acetate fraction, geraniin showed a higher activity than corilagin and gallic acid. The IC(50) values ranged from 0.87 to 2.53 microM, which were even lower than the positive control (except for allopurinol). All test samples except for the petroleum ether fraction showed xanthine oxidase inhibitory effects. We conclude that G. sibiricum represents a valuable natural antioxidant source and is potentially applicable in the healthy food industry.

  14. Antifungal activity of chitinase obtained from Paenibacillus ehimensis MA2012 against conidial of Collectotrichum gloeosporioides in vitro.

    PubMed

    Seo, Dong-Jun; Lee, Yong-Sung; Kim, Kil-Yong; Jung, Woo-Jin

    2016-07-01

    To investigate the expression patterns of chitinase on SDS-PAGE gel, Paenibacillus ehimensis MA2012 was incubated in gelatin-chitin medium (GCM) at 30 °C for 7 days. Six major bands (Ch3, Ch4, Ch5, Ch6, Ch7, and Ch8) of chitinase isozymes in GC medium appeared on SDS-PAGE gel during the incubation period. Chitinase activity staining of P. ehimensis MA2012 was detected on 2-DE with different pI values (4-11). After DEAE-Sephadex chromatography, eight bands (Ch1 to Ch8) of chitinase isozymes were stained strongly with Calcofluor white M2R at fraction 45. After Sephadex G-75 gel filtration, six bands (Ch3 to Ch8) of chitinase isozymes were stained with Calcofluor white M2R at fractions of 11-12. The specific activity of the purified chitinase was 3.8 units mg(-1) protein with a purification factor of 0.27. Inhibition rate of the conidial germination of Colletotrichum gloeosporioides was 87% in partial purified chitinase treatment compared with control. PMID:27133265

  15. The relationship between infliximab concentrations, antibodies to infliximab and disease activity in Crohn's disease

    PubMed Central

    Vande Casteele, Niels; Khanna, Reena; Levesque, Barrett G; Stitt, Larry; Zou, G Y; Singh, Sharat; Lockton, Steve; Hauenstein, Scott; Ohrmund, Linda; Greenberg, Gordon R; Rutgeerts, Paul J; Gils, Ann; Sandborn, William J; Vermeire, Séverine; Feagan, Brian G

    2015-01-01

    Objective Although low infliximab trough concentrations and antibodies to infliximab (ATI) are associated with poor outcomes in patients with Crohn's disease (CD), the clinical relevance of ATI in patients with adequate infliximab concentrations is uncertain. We evaluated this question using an assay sensitive for identification of ATI in the presence of infliximab. Design In an observational study, 1487 trough serum samples from 483 patients with CD who participated in four clinical studies of maintenance infliximab therapy were analysed using a fluid phase mobility shift assay. Infliximab and ATI concentrations most discriminant for remission, defined as a C-reactive protein concentration of ≤5 mg/L, were determined by receiver operating characteristic curves. A multivariable regression model evaluated these factors as independent predictors of remission. Results Based upon analysis of 1487 samples, 77.1% of patients had detectable and 22.9% had undetectable infliximab concentrations, of which 9.5% and 71.8%, respectively, were positive for ATI. An infliximab concentration of >2.79 μg/mL (area under the curve (AUC)=0.681; 95% CI 0.632 to 0.731) and ATI concentration of <3.15 U/mL (AUC=0.632; 95% CI 0.589 to 0.676) were associated with remission. Multivariable analysis showed that concentrations of both infliximab trough (OR 1.8; 95% CI 1.3 to 2.5; p<0.001) and ATI (OR 0.57; 95% CI 0.39 to 0.81; p=0.002) were independent predictors of remission. Conclusions The development of ATI increases the probability of active disease even at low concentrations and in the presence of a therapeutic concentration of drug during infliximab maintenance therapy. Evaluation of strategies to prevent ATI formation, including therapeutic drug monitoring with selective infliximab dose intensification, is needed. PMID:25336114

  16. Determination of phytochemicals and antioxidant activity of methanol extracts obtained from the fruit and leaves of Tunisian Lycium intricatum Boiss.

    PubMed

    Abdennacer, Boulila; Karim, Mattoussi; Yassine, M'rabet; Nesrine, Rokbeni; Mouna, Dhouioui; Mohamed, Boussaid

    2015-05-01

    A comparative analysis of methanol extracts from fruit and leaves of Lycium intricatum Boiss., a Solanaceous shrubbery with the potential to become a high-value crop, was performed by means of liquid chromatography with photodiode array and electrospray ionisation mass spectrometric detection (LC/PDA/ESI-MS). The total phenolic (TPC), anthocyanin (TAC) and flavonoid (TFC) contents as well as the antioxidant capacity measured by four complementary methods were performed for each sample. The results showed the tested extracts to be rich sources of phenolics; in leaves polyphenols and flavonoids dominate, while in fruit anthocyanins dominate. Nineteen phenolic compounds were detected and fifteen were identified or tentatively characterised based on Photodiode-array ultraviolet visible (PDA) UV-Vis spectra, ESI-MS spectrometric data and spiking experiments with authentic standards. Rutin and chlorogenic acid are the major constituents of the leaves and fruit, respectively. Results obtained in this study have revealed that leaves exhibit better performance in all antioxidant assays. From these results it has been shown that extracts of L. intricatum have great potential as a source of phenolics for natural health products.

  17. Time Evolution of Activity Concentration of Natural Emitters in a Scenario Affected By Previous Phosphogypsum Contamination

    NASA Astrophysics Data System (ADS)

    Villa, M.; Mantero, J.; Mosqueda, F.; Hurtado, S.; Manjón, G.; Vaca, F.; García-Tenorio, R.

    2008-08-01

    The estuary formed by the confluence of Tinto and Odiel river-mouths is located in the South of Spain, close to Huelva town. This estuary has been deeply studied through the years because it has a double particularity. On one hand, since the beginning of the 1960s, the estuary has been affected by direct and indirect phosphogypsum (pg.) releases from two phosphoric acid and fertilizers factories that are working in the area. On the other hand, the pyrite mining operations upstream the Odiel and Tinto rivers has caused historically the formation of H2SO4, through oxidation of the natural sulphur deposits, the acidification of the waters and the consequent mobilisation of heavy metals from the mining area to the Huelva estuary. As a consequence, enhancement contamination levels in natural emitters from the 238U series were found in the surroundings of the factories in the previous years to 1998. However, in 1998 the management policy of waste releases drastically changed in the area, and direct discharges to Tinto and Odiel River had to be ceased. A thorough study of the affected zone is being carried out. Riverbed sediments and water samples have been analyzed from four different sampling campaigns in the estuary during the years 1999, 2001, 2002 and 2005. Different radioanalytical techniques have been employed to obtain the activity concentrations of U-isotopes, Th-isotopes, 226Ra, 210Pb and 210Po. Furthermore, the results for the rates of de-contamination of the area are presented. This data will be discussed in order to establish the present status of the contamination in the area, and moreover, to predict the time-evolution of the self-cleaning

  18. Time Evolution of Activity Concentration of Natural Emitters in a Scenario Affected By Previous Phosphogypsum Contamination

    SciTech Connect

    Villa, M.; Hurtado, S.; Mantero, J.; Manjon, G.; Garcia-Tenorio, R.; Mosqueda, F.; Vaca, F.

    2008-08-07

    The estuary formed by the confluence of Tinto and Odiel river-mouths is located in the South of Spain, close to Huelva town. This estuary has been deeply studied through the years because it has a double particularity. On one hand, since the beginning of the 1960s, the estuary has been affected by direct and indirect phosphogypsum (pg.) releases from two phosphoric acid and fertilizers factories that are working in the area. On the other hand, the pyrite mining operations upstream the Odiel and Tinto rivers has caused historically the formation of H{sub 2}SO{sub 4}, through oxidation of the natural sulphur deposits, the acidification of the waters and the consequent mobilisation of heavy metals from the mining area to the Huelva estuary. As a consequence, enhancement contamination levels in natural emitters from the {sup 238}U series were found in the surroundings of the factories in the previous years to 1998. However, in 1998 the management policy of waste releases drastically changed in the area, and direct discharges to Tinto and Odiel River had to be ceased.A thorough study of the affected zone is being carried out. Riverbed sediments and water samples have been analyzed from four different sampling campaigns in the estuary during the years 1999, 2001, 2002 and 2005. Different radioanalytical techniques have been employed to obtain the activity concentrations of U-isotopes, Th-isotopes, {sup 226}Ra, {sup 210}Pb and {sup 210}Po. Furthermore, the results for the rates of de-contamination of the area are presented. This data will be discussed in order to establish the present status of the contamination in the area, and moreover, to predict the time-evolution of the self-cleaning.

  19. Spatial variability of dissolved phosphorous concentrations and alkaline phosphatase activity in the East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, H.; Chang, J.; Ho, T.; Gong, G.

    2010-12-01

    The concentrations of dissolved inorganic phosphorus (DIP) and alkaline phosphatase activity (APA) have been determined at about 25 sampling stations in the East China Sea since 2003. The stations are mainly distributed from the Changjiang river mouth to northern Taiwan and east to the shelf break. In addition to the Changjiang discharge, we have found a specific nutrient source around a coastal site (122° 2’30’’ E, 28° 40’ N). Elevated DIP and nitrate concentrations have been constantly observed around the sampling station for 8 years, where the surface DIP concentrations are generally around 0.3 µM. The nutrient source may either originate from ground water discharge or coastal upwelling, where lower temperature has been observed in the water column around the station. In general, APA has been negatively correlated with DIP concentrations in the studies sites, with lowest APA around the high DIP station and the Changjiang river mouth.

  20. Association between serum trace element concentrations and the disease activity of systemic lupus erythematosus.

    PubMed

    Sahebari, M; Abrishami-Moghaddam, M; Moezzi, A; Ghayour-Mobarhan, M; Mirfeizi, Z; Esmaily, H; Ferns, G

    2014-07-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease with a complex, incompletely understood, etiology. Several genetic and environmental factors are suspected to be involved in its aetiology. Oxidative stress may be implicated in the pathogenesis of SLE and may be affected by trace element status. Zinc (Zn), copper (Cu) and selenium (Se) are essential components of several anti-oxidative enzymes and are also involved in several immune functions. The current study aimed to assess the relationship between serum concentrations of these trace elements and the clinical disease activity of SLE assessed using the SLE disease activity index (SLEDAI). Serum concentrations of albumin (Alb) (p = 0.001), Se (p = 0.001), Zn (p = 0.001) and the Zn to Cu ratio (Zn/Cu R) (p = 0.001) were lower in patients with SLE than the age- and sex-matched healthy controls. However, only Alb (p = 0.001) and Cu (p = 0.03) were negatively correlated with disease activity, which was supported by regression analysis. In summary, lower serum values of Alb, Zn, Se and Zn/Cu R were found in SLE patients compared with healthy controls; however, in addition to serum Alb concentrations, serum Cu concentrations were also negatively correlated with lupus disease activity.

  1. Post-Chernobyl investigations of radiocaesium activity concentrations in Adriatic Sea pilchards.

    PubMed

    Franić, Zdenko; Petrinec, Branko; Branica, Gina; Marović, Gordana; Kubelka, Dragan; Franić, Zrinka

    2012-08-01

    Investigations in the post-Chernobyl period (1986-2009) of radiocaesium activity concentrations in Adriatic pilchards are presented. Compared with pre-Chernobyl period, the Chernobyl nuclear accident caused increase of (137)Cs activity concentrations in pilchards. By fitting the measured (137)Cs activity concentrations to the theoretical curve was estimated to be 1.5±0.4 y for 1986-90 and 5.8±0.4 y for 1991-2009 and the bimodal behaviour for the ecological half-life of (137)Cs in pilchards has been observed. Estimated annual effective doses received by (134)Cs and (137)Cs intake due to consumption for an adult member of Croatian population are small. Collective dose for the 1986-2009 period was 4.9+0.3 person-Sv. The observed (134)Cs/(137)Cs activity ratio in pilchards was similar to the ratio that has been found in other environmental samples. The concentration factor for pilchards was roughly estimated to be 93.7±39.2 l kg(-1), which is consistent with the values observed elsewhere.

  2. Differential effects of mental concentration and acute psychosocial stress on cervical muscle activity and posture.

    PubMed

    Shahidi, Bahar; Haight, Ashley; Maluf, Katrina

    2013-10-01

    Physical and psychosocial stressors in the workplace have been independently associated with the development of neck pain, yet interactions among these risk factors remain unclear. The purpose of this study was to compare the effects of mentally challenging computer work performed with and without exposure to a psychosocial stressor on cervical muscle activity and posture. Changes in cervical posture and electromyography of upper trapezius, cervical extensor, and sternocleidomastoid muscles were compared between a resting seated posture at baseline, a low stress condition with mental concentration, and a high stress condition with mental concentration and psychosocial stress in sixty healthy office workers. Forward head posture significantly increased with mental concentration compared to baseline, but did not change with further introduction of the stressor. Muscle activity significantly increased from the low stress to high stress condition for both the dominant and non-dominant upper trapezius, with no corresponding change in activity of the cervical extensors or flexors between stress conditions. These findings suggest that upper trapezius muscles are selectively activated by psychosocial stress independent of changes in concentration or posture, which may have implications for the prevention of stress-related trapezius myalgia in the workplace.

  3. 76 FR 48882 - Agency Information Collections Activities; Comment Request for Uranium Concentrations in Private...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-09

    ... U.S. Geological Survey Agency Information Collections Activities; Comment Request for Uranium... Collection 1028-NEW, Uranium concentrations in private wells in south-east New Hampshire, in the subject line... telephone (970) 226-9165; or schusterr@usgs.gov (e-mail). SUPPLEMENTARY INFORMATION: I. Abstract...

  4. Combined effects of water temperature and copper ion concentration on catalase activity in Crassostrea ariakensis

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Yang, Hongshuai; Liu, Jiahui; Li, Yanhong; Liu, Zhigang

    2015-07-01

    A central composite experimental design and response surface method were used to investigate the combined effects of water temperature (18-34°C) and copper ion concentration (0.1-1.5 mg/L) on the catalase (CAT) activity in the digestive gland of Crassostrea ariakensis. The results showed that the linear effects of temperature were significant ( P<0.01), the quadratic effects of temperature were significant ( P<0.05), the linear effects of copper ion concentration were not significant ( P>0.05), and the quadratic effects of copper ion concentration were significant ( P<0.05). Additionally, the synergistic effects of temperature and copper ion concentration were not significant ( P>0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution.

  5. Metal Concentrations in Two Commercial Tuna Species from an Active Volcanic Region in the Mid-Atlantic Ocean.

    PubMed

    Torres, Paulo; Rodrigues, Armindo; Soares, Lília; Garcia, Patrícia

    2016-02-01

    Concentrations of cadmium (Cd), mercury (Hg), and lead [Pb (µg g(-1) wet weight)] were determined in liver and muscle samples of 15 bigeye (Thunnus obesus) and 15 skipjack tunas (Katsuwonus pelamis) caught over an active volcanic region in the Mid-Atlantic Ocean (Azores, Portugal) and evaluated regarding consumption safety. None of the muscle samples (edible part) exceeded the European Union (EU) maximum limits (MLs) for Hg and Pb. Cd concentrations in muscle were much greater than EU MLs with 53 and 26 % of the bigeye tuna and skipjack tuna, respectively, in exceedance of the limits. Results obtained in this work, together with other studies in the same region, support the existence of an important volcanic source of Cd in waters of the Mid-Atlantic region, which should be carefully monitored given the importance of many commercial marine species for human consumption, mainly in Europe. PMID:26681184

  6. Metal Concentrations in Two Commercial Tuna Species from an Active Volcanic Region in the Mid-Atlantic Ocean.

    PubMed

    Torres, Paulo; Rodrigues, Armindo; Soares, Lília; Garcia, Patrícia

    2016-02-01

    Concentrations of cadmium (Cd), mercury (Hg), and lead [Pb (µg g(-1) wet weight)] were determined in liver and muscle samples of 15 bigeye (Thunnus obesus) and 15 skipjack tunas (Katsuwonus pelamis) caught over an active volcanic region in the Mid-Atlantic Ocean (Azores, Portugal) and evaluated regarding consumption safety. None of the muscle samples (edible part) exceeded the European Union (EU) maximum limits (MLs) for Hg and Pb. Cd concentrations in muscle were much greater than EU MLs with 53 and 26 % of the bigeye tuna and skipjack tuna, respectively, in exceedance of the limits. Results obtained in this work, together with other studies in the same region, support the existence of an important volcanic source of Cd in waters of the Mid-Atlantic region, which should be carefully monitored given the importance of many commercial marine species for human consumption, mainly in Europe.

  7. Ovicidal activity of different concentrations of Pochonia chlamydosporia chlamydospores on Taenia taeniaeformis eggs.

    PubMed

    Braga, F R; Silva, A R; Carvalho, R O; Araújo, J V; Pinto, P S A

    2011-03-01

    Three concentrations of chlamydospores of the nematophagous fungus Pochonia chlamydosporia (1000, 10,000 and 20,000 per Petri dish) were evaluated in vitro on Taenia taeniaeformis eggs. Chlamydospores at each concentration were cultured in two different media: 2% water-agar (2%WA) and 2% corn-meal-agar (2%CMA). Taenia taeniaeformis eggs were plated in each chlamydospore concentration in 2%WA and 2%CMA (treated groups) and without fungus (control group). Eggs were removed from each Petri dish at intervals of 7, 14 and 21 days and classified according to ovicidal activity (type 1, type 2 and type 3 effects). Plates containing 2%CMA showed the highest percentages for type 3 effect (81.3%) on the 21st day of observation. A difference (P < 0.01) between the media 2%WA and 2%CMA for type 1 effect was observed only at a concentration of 1000 chlamydospores on the 7th day. There were differences (P < 0.01) between 2%WA and 2%CMA on the 14th and 21st days, at the concentration of 20,000 chlamydospores, for type 1 and type 3 effects. Regression curves for type 3 effect in 2%WA and 2%CMA at the tested concentrations showed higher ovicidal activity with increasing chlamydospore concentrations. Results indicate that, at concentrations of 1000, 10,000 and 20,000 per Petri dish, chlamydospores of P. chlamydosporia effectively destroyed T. taeniaeformis eggs and can be considered a potential biological control agent for this cestode. PMID:20338078

  8. Low Concentrations of Hydrogen Peroxide Activate the Antioxidant Defense System in Human Sperm Cells.

    PubMed

    Evdokimov, V V; Barinova, K V; Turovetskii, V B; Muronetz, V I; Schmalhausen, E V

    2015-09-01

    The effect of low concentrations of hydrogen peroxide (10-100 µM) on sperm motility and on the activity of the sperm enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDS) was investigated. Incubation of semen samples with 10 and 100 µM hydrogen peroxide increased the content of spermatozoa with progressive motility by 20 and 18%, respectively, and enhanced the activity of GAPDS in the sperm cells by 27 and 20% compared to a semen sample incubated without additions. It was also found that incubation with 10 µM hydrogen peroxide increased the content of reduced glutathione (GSH) in sperm cells by 50% on average compared to that in the control samples. It is supposed that low concentrations of hydrogen peroxide activate the pentose phosphate pathway, resulting in NADPH synthesis and the reduction of the oxidized glutathione by glutathione reductase yielding GSH. The formed GSH reduces the oxidized cysteine residues of the GAPDS active site, increasing the activity of the enzyme, which in turn enhances the content of sperm cells with progressive motility. Thus, the increase in motile spermatozoa in the presence of low concentrations of hydrogen peroxide can serve as an indicator of normal functioning of the antioxidant defense system in sperm cells.

  9. Influence of physical activity on concentration among junior high-school students.

    PubMed

    Raviv, S; Low, M

    1990-02-01

    The level and quality of concentration were tested before and after each lesson in one class session. Two of the four classes participated in physical education activities, and the other two studied science. Each subject matter was studied the beginning and at the end of the school day. The research design was 2 x 2 x 2 factorial (two subject matters, two times of the school day, and as a repeated measure two times of test for each group at the beginning and end of each lesson). The level and the quality of concentration found at the end of each lesson were significantly higher than at the beginning. The subject matters did not influence concentration. It may be concluded that the time of day was the main influence on concentration, so teachers' claims against physical education activity lessons can be rejected. The increase in concentration toward the end of the lesson implies the need for careful lesson planning or even the consideration of increasing duration of lessons.

  10. PON-1 Activity and Plasma 8-Isoprostane Concentration in Patients with Angiographically Proven Coronary Artery Disease

    PubMed Central

    Kuchta, Agnieszka; Strzelecki, Adrian; Ćwiklińska, Agnieszka; Totoń, Magdalena; Gruchała, Marcin; Zdrojewski, Zbigniew; Kortas-Stempak, Barbara; Gliwińska, Anna; Dąbkowski, Kamil; Jankowski, Maciej

    2016-01-01

    The aim of the study was to estimate association of the extent of angiographically proven coronary artery disease (CAD) with plasma 8-isoprostane F2 (8-iso-PGF2α) levels as a reliable marker of lipid peroxidation and serum activity of paraoxonase-1, which demonstrates the ability to protect against lipid oxidation. The study included 105 patients with angiographically documented CAD (CAD+) and 45 patients with negative results of coronary angiography (CAD−). Compared to the control group CAD+ patients were characterized by increased 8-iso-PGF2α levels (P = 0.007) and reduced activity of PON-1 towards paraoxon (PONase, P = 0.002) and phenyl acetate (AREase, P = 0.037). Univariate correlation analysis indicated that 8-iso-PGF2α concentrations were positively associated with the severity of CAD as evaluated by the Gensini score (R = 0.41, P < 0.001) while PONase activity (R = −0.26, P < 0.05) and AREase activity (R = −0.23, P < 0.05) were inversely correlated with CAD severity. PONase activity and 8-iso-PGF2α concentration remained independent determinant of atherosclerosis severity in multiple linear regression after adjusting for age, gender, smoking habits, hypertension, type 2 diabetes, statin therapy, and HDL-C and TAG concentration (β coefficients −0.267; P < 0.05 and 0.368; P < 0.001, resp.). The results suggest that PON-1 activity and 8-iso-PGF2α concentration are associated with the presence and extent of coronary stenosis and may be considered additional markers of coronary artery disease. PMID:26697134

  11. Validation of the concentration profiles obtained from the near infrared/multivariate curve resolution monitoring of reactions of epoxy resins using high performance liquid chromatography as a reference method.

    PubMed

    Garrido, M; Larrechi, M S; Rius, F X

    2007-03-01

    This paper reports the validation of the results obtained by combining near infrared spectroscopy and multivariate curve resolution-alternating least squares (MCR-ALS) and using high performance liquid chromatography as a reference method, for the model reaction of phenylglycidylether (PGE) and aniline. The results are obtained as concentration profiles over the reaction time. The trueness of the proposed method has been evaluated in terms of lack of bias. The joint test for the intercept and the slope showed that there were no significant differences between the profiles calculated spectroscopically and the ones obtained experimentally by means of the chromatographic reference method at an overall level of confidence of 5%. The uncertainty of the results was estimated by using information derived from the process of assessment of trueness. Such operational aspects as the cost and availability of instrumentation and the length and cost of the analysis were evaluated. The method proposed is a good way of monitoring the reactions of epoxy resins, and it adequately shows how the species concentration varies over time.

  12. Determination of uranium, thorium and potassium activity concentrations in soil cores in Araba valley, Jordan.

    PubMed

    Abusini, M; Al-Ayasreh, K; Al-Jundi, J

    2008-01-01

    Soil samples were collected from six different locations in Araba valley, situated between Aqaba port and Dead sea. The samples have been analysed by using gamma-ray spectrometry. From the measured gamma-ray spectra, activity concentrations are determined for (238)U, (232)Th and (40)K. The mean activity concentration for (238)U, (232)Th and (40)K was found to be in the range 19 +/- 1.4 to 38.7 +/- 3, 14.3 +/- 0.8 to 35 +/- 3.2 and 94 +/- 18.9 to 762 +/- 47.4 Bq kg(-1), respectively. These results indicate that the mean concentrations of (238)U, (232)Th and (40)K in the populated Araba valley are lower than those in other populated areas. On the other hand, the concentrations of the major oxides (Al(2)O(3), SiO(2), K(2)O, CaO and Fe(2)O(3)) in the samples were determined using wavelength dispersive X-ray fluorescence. High potassium and iron content in some samples might be attributed to the active faults, which refer to the Dead sea transform fault.

  13. Effects of chlordecone on 20-hydroxyecdysone concentration and chitobiase activity in a decapod crustacean, Macrobrachium rosenbergii.

    PubMed

    Lafontaine, Anne; Gismondi, Eric; Boulangé-Lecomte, Céline; Geraudie, Perrine; Dodet, Nathalie; Caupos, Fanny; Lemoine, Soazig; Lagadic, Laurent; Thomé, Jean-Pierre; Forget-Leray, Joëlle

    2016-07-01

    Chlordecone (CLD) is an organochlorine insecticide abundant in aquatic environment of the French West Indies. However, few studies have investigated its impact on freshwater invertebrates. Whereas CLD is suspected of inducing endocrine disruption, this work aimed to study the effects of environmentally relevant concentrations of CLD on the 20-hydroxyecdysone (20-HE) hormone concentration and on the chitobiase activity, both having key roles in the molting process of crustaceans. In addition, the bioaccumulation of CLD was measured in the muscle tissue of Macrobrachium rosenbergii to underline potential dose-response relationship. The results have shown that CLD was bioaccumulated in exposed organisms according to a trend to a dose-response relationship. Moreover, it was observed that CLD decreased the 20-HE concentration in exposed prawns when compared to control, whatever the duration of exposure, as well as it inhibited the chitobiase activity after 30days of exposure. The present study indicates that CLD could interfere with molting process of M. rosenbergii by disturbing the 20-HE concentration and the activity of chitobiase, suggesting consequences at the long term on the shrimp development. This study also confirmed that CLD could be an endocrine disruptor in decapod crustaceans, as it was already observed in vertebrates.

  14. Variation of PM2.5 concentrations in relation to street washing activities

    NASA Astrophysics Data System (ADS)

    Karanasiou, Angeliki; Moreno, Teresa; Amato, Fulvio; Tobías, Aurelio; Boldo, Elena; Linares, Cristina; Lumbreras, Julio; Borge, Rafael; Alastuey, Andrés; Querol, Xavier

    2012-07-01

    Several studies conducted in urban areas have pointed out that road dust resuspension contributes significantly to PM concentration levels. Street washing is one of the methods proposed to reduce resuspended road dust contributions to ambient PM concentrations. As resuspended particles are mainly found in the coarse mode, published studies investigating the effects of street washing have focused on PM10 size fraction. As the PM2.5 mass fraction of particles originating from mechanical abrasion processes may still be significant we conducted a study in order to evaluate the effects of street washing on the mitigation of resuspension of fine particles. The PM2.5 mass concentration data were examined and integrated with the occurrence of street washing activities. In addition, the effect of the meteorological variability, traffic flow and street washing activities, on ambient PM2.5 levels was evaluated by means of a multivariate regression model. The results revealed that traffic flow is the most important factor that controls PM2.5 hourly concentrations while street washing activities did not influence fine particle mass levels.

  15. Effects of chlordecone on 20-hydroxyecdysone concentration and chitobiase activity in a decapod crustacean, Macrobrachium rosenbergii.

    PubMed

    Lafontaine, Anne; Gismondi, Eric; Boulangé-Lecomte, Céline; Geraudie, Perrine; Dodet, Nathalie; Caupos, Fanny; Lemoine, Soazig; Lagadic, Laurent; Thomé, Jean-Pierre; Forget-Leray, Joëlle

    2016-07-01

    Chlordecone (CLD) is an organochlorine insecticide abundant in aquatic environment of the French West Indies. However, few studies have investigated its impact on freshwater invertebrates. Whereas CLD is suspected of inducing endocrine disruption, this work aimed to study the effects of environmentally relevant concentrations of CLD on the 20-hydroxyecdysone (20-HE) hormone concentration and on the chitobiase activity, both having key roles in the molting process of crustaceans. In addition, the bioaccumulation of CLD was measured in the muscle tissue of Macrobrachium rosenbergii to underline potential dose-response relationship. The results have shown that CLD was bioaccumulated in exposed organisms according to a trend to a dose-response relationship. Moreover, it was observed that CLD decreased the 20-HE concentration in exposed prawns when compared to control, whatever the duration of exposure, as well as it inhibited the chitobiase activity after 30days of exposure. The present study indicates that CLD could interfere with molting process of M. rosenbergii by disturbing the 20-HE concentration and the activity of chitobiase, suggesting consequences at the long term on the shrimp development. This study also confirmed that CLD could be an endocrine disruptor in decapod crustaceans, as it was already observed in vertebrates. PMID:27108204

  16. Limiting concentrations of activated mononucleotides necessary for poly(C)-directed elongation of oligoguanylates

    NASA Technical Reports Server (NTRS)

    Kanavarioti, A.; Chang, S.; Alberas, D. J.

    1990-01-01

    Selected imidazolide-activated nucleotides have been subjected to hydrolysis under conditions similar to those that favor their template-directed oligomerization. Rate constants of hydrolysis of the P-N bond in guanosine 5'-monophosphate 2-methylimidazolide (2-MeImpG) and in guanosine 5'-monophosphate imidazolide (ImpG), kh, have been determined in the presence/absence of magnesium ion as a function of temperature and polycytidylate [poly(C)] concentration. Using the rate constant of hydrolysis of 2-MeImpG and the rate constant of elongation, i.e., the reaction of an oligoguanylate with 2-MeImpG in the presence of poly(C) acting as template, the limiting concentration of 2-MeImpG necessary for oligonucleotide elongation to compete with hydrolysis can be calculated. The limiting concentration is defined as the initial concentration of monomer that results in its equal consumption by hydrolysis and by elongation. These limiting concentrations of 2-MeImpG are found to be 1.7 mM at 37 degrees C and 0.36 mM at 1 degrees C. Boundary conditions in the form of limiting concentration of activated nucleotide may be used to evaluate a prebiotic model for chemical synthesis of biopolymers. For instance, the limiting concentration of monomer can be used as a basis of comparison among catalytic, but nonenzymatic, RNA-type systems. We also determined the rate constant of dimerization of 2-MeImpG, k2 = 0.45 +/- 0.06 M-1 h-1 in the absence of poly(C), and 0.45 +/- 0.06 less than or equal to k2 less than or equal to 0.97 +/- 0.13 M-1 h-1 in its presence at 37 degrees C and pH 7.95.(ABSTRACT TRUNCATED AT 250 WORDS).

  17. Effect of active-ion concentration on holmium fibre laser efficiency

    SciTech Connect

    Kurkov, Andrei S; Sholokhov, E M; Marakulin, A V; Minashina, L A

    2010-08-03

    We have measured the fraction of holmium ions that relax nonradiatively to the ground level as a result of interaction at a metastable level in optical fibres with a silica-based core doped with holmium ions to 2 x 10{sup 19} - 2 x 10{sup 20} cm{sup -3}. The percentage of such ions has been shown to depend on the absolute active-ion concentration. The fibres have been used to make a number of 2.05-{mu}m lasers, and their slope efficiency has been measured. The laser efficiency decreases with increasing holmium concentration in the fibres (lasers)

  18. Effect of elevated serum prolactin concentrations on cytokine production and natural killer cell activity.

    PubMed

    Clodi, M; Svoboda, T; Kotzmann, H; Deyssig, R; Woloszczuk, W; Zielinski, C C; Luger, A

    1992-12-01

    In vitro and in vivo studies in rodents and human suggested an immunostimulatory effect of prolactin. The aim of the present study was to determine the impact of chronically elevated serum prolactin concentrations on the immune system in patients with prolactinomas. For this purpose parameters of the humoral and cellular immune system were studied in seven patients with prolactinomas on two occasions (1) when their serum prolactin concentration had been normalized through treatment with dopamine agonists and (2) when their serum prolactin concentration was high. Serum concentrations of immunoglobulines, interleukin 1, 3 and 6, TNF-alpha, interferon-gamma and the soluble interleukin 2 receptor, leukocyte subsets and the natural killer cell activity were found to be within the normal range on both occasions, i.e. at normal and at high serum prolactin concentrations. The assumption could be made that long-lasting elevation of serum prolactin concentration induces adaptive changes when the acute stimulatory effects of prolactin on several parameters of the immune system have subsided.

  19. Influence of Traffic Activity on Heavy Metal Concentrations of Roadside Farmland Soil in Mountainous Areas

    PubMed Central

    Zhang, Fan; Yan, Xuedong; Zeng, Chen; Zhang, Man; Shrestha, Suraj; Devkota, Lochan Prasad; Yao, Tandong

    2012-01-01

    Emission of heavy metals from traffic activities is an important pollution source to roadside farmland ecosystems. However, little previous research has been conducted to investigate heavy metal concentrations of roadside farmland soil in mountainous areas. Owing to more complex roadside environments and more intense driving conditions on mountainous highways, heavy metal accumulation and distribution patterns in farmland soil due to traffic activity could be different from those on plain highways. In this study, design factors including altitude, roadside distance, terrain, and tree protection were considered to analyze their influences on Cu, Zn, Cd, and Pb concentrations in farmland soils along a mountain highway around Kathmandu, Nepal. On average, the concentrations of Cu, Zn, Cd, and Pb at the sampling sites are lower than the tolerable levels. Correspondingly, pollution index analysis does not show serious roadside pollution owing to traffic emissions either. However, some maximum Zn, Cd, and Pb concentrations are close to or higher than the tolerable level, indicating that although average accumulations of heavy metals pose no hazard in the region, some spots with peak concentrations may be severely polluted. The correlation analysis indicates that either Cu or Cd content is found to be significantly correlated with Zn and Pb content while there is no significant correlation between Cu and Cd. The pattern can be reasonably explained by the vehicular heavy metal emission mechanisms, which proves the heavy metals’ homology of the traffic pollution source. Furthermore, the independent factors show complex interaction effects on heavy metal concentrations in the mountainous roadside soil, which indicate quite a different distribution pattern from previous studies focusing on urban roadside environments. It is found that the Pb concentration in the downgrade roadside soil is significantly lower than that in the upgrade soil while the Zn concentration in the

  20. Positron emission mammography (PEM): Effect of activity concentration, object size, and object contrast on phantom lesion detection

    SciTech Connect

    MacDonald, Lawrence R.; Wang, Carolyn L.; Eissa, Marna; Haseley, David; Kelly, Mary M.; Liu, Franklin; Parikh, Jay R.; Beatty, J. David; Rogers, James V.

    2012-10-15

    Purpose: To characterize the relationship between lesion detection sensitivity and injected activity as a function of lesion size and contrast on the PEM (positron emission mammography) Flex Solo II scanner using phantom experiments. Methods: Phantom lesions (spheres 4, 8, 12, 16, and 20 mm diameter) were randomly located in uniform background. Sphere activity concentrations were 3 to 21 times the background activity concentration (BGc). BGc was a surrogate for injected activity; BGc ranged from 0.44-4.1 kBq/mL, corresponding to 46-400 MBq injections. Seven radiologists read 108 images containing zero, one, or two spheres. Readers used a 5-point confidence scale to score the presence of spheres. Results: Sensitivity was 100% for lesions {>=}12 mm under all conditions except for one 12 mm sphere with the lowest contrast and lowest BGc (60% sensitivity). Sensitivity was 100% for 8 mm spheres when either contrast or BGc was high, and 100% for 4 mm spheres only when both contrast and BGc were highest. Sphere contrast recovery coefficients (CRC) were 49%, 34%, 26%, 14%, and 2.8% for the largest to smallest spheres. Cumulative specificity was 98%. Conclusions: Phantom lesion detection sensitivity depends more on sphere size and contrast than on BGc. Detection sensitivity remained {>=}90% for injected activities as low as 100 MBq, for lesions {>=}8 mm. Low CRC in 4 mm objects results in moderate detection sensitivity even for 400 MBq injected activity, making it impractical to optimize injected activity for such lesions. Low CRC indicates that when lesions <8 mm are observed on PEM images they are highly tracer avid with greater potential of clinical significance. High specificity (98%) suggests that image statistical noise does not lead to false positive findings. These results apply to the 85 mm thick object used to obtain them; lesion detectability should be better (worse) for thinner (thicker) objects based on the reduced (increased) influence of photon attenuation.

  1. Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration

    SciTech Connect

    Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.; Burgos, Patricia V.; Villanueva, Carolina I.; Figueroa, Carlos D.; González, Carlos B.

    2013-11-29

    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. The 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.

  2. High concentrations of single-walled carbon nanotubes lower soil enzyme activity and microbial biomass.

    PubMed

    Jin, Lixia; Son, Yowhan; Yoon, Tae Kyung; Kang, Yu Jin; Kim, Woong; Chung, Haegeun

    2013-02-01

    Nanomaterials such as single-walled carbon nanotubes (SWCNTs) may enter the soil environment with unknown consequences resulting from the development of nanotechnology for a variety of applications. We determined the effects of SWCNTs on soil enzyme activity and microbial biomass through a 3-week incubation of urban soils treated with different concentrations of SWCNTs ranging from 0 to 1000 μg g(-1) soil. The activities of cellobiohydrolase, β-1,4-glucosidase, β-1,4-xylosidase, β-1,4-N-acetylglucosaminidase, L-leucine aminopeptidase, and acid phosphatase and microbial biomass were measured in soils treated with powder and suspended forms of SWCNTs. SWCNTs of concentrations at 300-1000 μg g(-1) soil significantly lowered activities of most enzymes and microbial biomass. It is noteworthy that the SWCNTs showed similar effects to that of multi-walled carbon nanotubes (MWCNTs), but at a concentration approximately 5 times lower; we suggest that this is mainly due to the higher surface area of SWCNTs than that of MWCNTs. Indeed, our results show that surface area of CNTs has significant negative relationship with relative enzyme activity and biomass, which suggests that greater microorganism-CNT interactions could increase the negative effect of CNTs on microorganisms. Current work may contribute to the preparation of a regulatory guideline for the release of CNTs to the soil environment.

  3. Elevated blood plasma concentrations of active ghrelin and obestatin in benign ovarian neoplasms and ovarian cancers.

    PubMed

    Markowska, A; Ziółkowska, A; Jaszczyńska-Nowinka, K; Madry, R; Malendowicz, L K

    2009-01-01

    Both ghrelin and obestatin are derived from preproghrelin by post-translational processing. The two peptides are secreted into the blood but circulating levels of these peptides have not been assessed in women with ovarian tumours. Therefore, the purpose of this study was to evaluate peripheral blood concentrations of active and total ghrelin and obestatin in patients with benign ovarian tumours and those with ovarian cancer. The studies were conducted on 22 patients operated due to benign ovarian tumours, and 31 patients operated due to ovarian cancer. A control group consisted of 32 women, 24 to 65 years of age. Both in women with benign ovarian tumours and those with ovarian cancer blood concentrations of active ghrelin and obestatin were higher than in the control group (active ghrelin: 90 +/- 4, 84 +/- 4 and 56 +/- 9 pg/ml, respectively, obestatin: 660 +/- 36; 630 +/- 30 and 538 +/- 31 ng/ml (x +/- SE), respectively). In contrast, total ghrelin concentrations in blood were similar in the studied groups. The alterations resulted in increased values of active to total ghrelin concentration ratio in the peripheral blood of patients with benign ovarian tumours or with ovarian cancer (0.79 +/- 0.02 and 0.93 +/- 0.05, respectively vs 0.58 +/- 0.02 in the control group). Due to the absence of any convincing proof for the presence of a functional GHS-R-1a receptor for ghrelin in human ovaries it did not seem probable that the observed elevated levels of active ghrelin and obestatin were directly linked to development of ovarian tumours.

  4. Platelet Activation by Low Concentrations of Intact Oxidized LDL Particles Involves the PAF Receptor

    PubMed Central

    Chen, Rui; Chen, Xi; Salomon, Robert G.; McIntyre, Thomas M.

    2008-01-01

    Objective Mitochondrial depolarization aids platelet activation. Oxidized LDL (oxLDL) contains the medium length oxidatively truncated phospholipid hexadecyl azelaoyl-lysoPAF (HAz-LPAF) that disrupts mitochondrial function in nucleated cells, so oxLDL may augment platelet activation. Methods and Results Flow cytometry showed intact oxLDL particles synergized with sub-threshold amounts of soluble agonists to increase intracellular Ca++, and initiate platelet aggregation and surface expression of activated gpIIb/IIIa and P-selectin. oxLDL also induced aggregation and increased intracellular Ca++ in FURA2-labeled cells by itself at low, although not higher, concentrations. HAz-LPAF, alone and in combination with sub-stimulatory amounts of thrombin, rapidly increased cytoplasmic Ca++ and initiated aggregation. HAz-LPAF depolarized mitochondria in intact platelets, but this required concentrations beyond those that directly activated platelets. An unexpectedly large series of chemically pure truncated phospholipids generated by oxidative fragmentation of arachidonoyl-, docosahexaneoyl-, or linoleoyl alkyl phospholipids were platelet agonists. The PAF receptor, thought to effectively recognize only phospholipids with very short sn-2 residues, was essential for platelet activation because PAF receptor agonists blocked signaling by all these medium length phospholipids and oxLDL. Conclusions Intact oxLDL particles activate platelets through the PAF receptor, and the PAF receptor responds to a far wider range of oxidized phospholipids in oxLDL than anticipated. PMID:19112165

  5. Ultrastructural characteristics of fibrin clots from canine and feline platelet concentrates activated with calcium gluconate or calcium gluconate plus batroxobin

    PubMed Central

    2013-01-01

    Background The aim of this study was to use transmission electron microscopy to describe the ultrastructural characteristics of clots obtained from canine and feline platelet concentrates (PC) that had been activated with calcium gluconate (CG) or CG plus batroxobin (CGB). Platelets from fibrin clots were classified according their morphological changes. The area of the intercellular space (μm2), the area of the fibrin fibers (μm2), and the width of the fibrin fibers (μm) were determined for the dog clots. The platelet area (μm2), the area of fibrin fibers (μm2), the ratio of the minor and major axes of platelets, the ratio of the major and minor axes of platelets, and the number of α-granules found within platelets were measured for the cat clots. Results Cat platelets displayed full activation. Dog platelets displayed lysis with loss of normal architecture. In both species, a statistically significant difference was found (P < 0.01) between the fibrin fiber measurements in the PC clots activated with CG and CGB. Conclusions The findings suggest that activation with CG caused platelet alpha granules to release their contents. In cats, fibrin production was greater when the PC was activated with CG. In dogs, activation with CG produced thick fibrin fibers. PMID:23587176

  6. Evaluation of activated carbon respirator filter effectiveness by concentration mapping of dimethyl methylphosphonate.

    PubMed

    Mitchell, Brendan L; Billingsley, Brit G; Logue, Brian A

    2014-01-01

    Activated carbon (AC) has been used extensively in personal protective equipment (PPE) to adsorb toxic substances for the purpose of protecting the user from exposure. The ability to evaluate localized carbon utilization in multiple PPE designs would help engineers develop more effective PPE. Therefore, a method to map dimethyl methylphosphonate (DMMP), a common PPE testing agent, concentrations throughout AC filters was developed and tested on DMMP-exposed filters, some purposefully occluded to simulate defective filters. DMMP concentrations were highest at the point of entry and dispersed outward in a radial pattern from that site, decreasing with distance from the point of exposure. Occluded filters were detected by observing DMMP adsorption inconsistent with unblocked filters and showed high concentrations of DMMP localized in unblocked areas of the filter. The DMMP mapping technique detailed in this study provides a tool for testing AC utilization inside DMMP-exposed PPE. PMID:24517267

  7. Primary centers and secondary concentrations of tectonic activity through time in the western hemisphere of Mars

    USGS Publications Warehouse

    Anderson, R.C.; Dohm, J.M.; Golombek, M.P.; Haldemann, A.F.C.; Franklin, B.J.; Tanaka, K.L.; Lias, J.; Peer, B.

    2001-01-01

    Five main stages of radial and concentric structures formed around Tharsis from the Noachian through the Amazonian as determined by geologic mapping of 24,452 structures within the stratigraphic framework of Mars and by testing their radial and concentric orientations. Tectonic activity peaked in the Noachian (stage 1) around the largest center, Claritas, an elongate center extending more than 20?? in latitude and defined by about half of the total grabens which are concentrated in the Syria Planum, Thaumasia, and Tempe Terra regions. During the Late Noachian and Early Hesperian (stage 2), extensional structures formed along the length of present-day Valles Marineris and in Thaumasia (with a secondary concentration near Warrego Vallis) radial to a region just to the south of the central margin of Valles Marineris. Early Hesperian (stage 3) radial grabens in Pavonis, Syria, Ulysses, and Tempe Terra and somewhat concentric wrinkle ridges in Lunae and Solis Plana and in Thaumasia, Sirenum, Memnonia, and Amazonis are centered northwest of Syria with secondary centers at Thaumasia, Tempe Terra, Ulysses Fossae, and western Valles Marineris. Late Hesperian/Early Amazonian (stage 4) structures around Alba Patera, the northeast trending alignment of Tharsis Montes, and Olympus Mons appears centered on Alba Patera. Stage 5 structures (Middle-Late Amazonian) represent the last pulse of Tharsis-related activity and are found around the large shield volcanoes and are centered near Pavonis Mons. Tectonic activity around Tharsis began in the Noachian and generally decreased through geologic time to the Amazonian. Statistically significant radial distributions of structures formed during each stage, centered at different locations within the higher elevations of Tharsis. Secondary centers of radial structures during many of the stages appear related to previously identified local magmatic centers that formed at different times and locations throughout Tharsis. Copyright 2001 by

  8. Mercury Inhibits Soil Enzyme Activity in a Lower Concentration than the Guideline Value.

    PubMed

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Megharaj, Mallavarapu; Naidu, Ravi

    2016-01-01

    Three soil types - neutral, alkaline and acidic were experimentally contaminated with nine different concentrations of inorganic mercury (0, 5, 10, 50, 100, 150, 200, 250, 300 mg/kg) to derive effective concentrations of mercury that exert toxicity on soil quality. Bioavailability of mercury in terms of water solubility was lower in acidic soil with higher organic carbon. Dehydrogenase enzyme activity and nitrification rate were chosen as indicators to assess soil quality. Inorganic mercury significantly inhibited (p < 0.001) microbial activities in the soils. The critical mercury contents (EC10) were found to be less than the available safe limits for inorganic mercury which demonstrated inadequacy of existing guideline values.

  9. Effect of Fe doping concentration on photocatalytic activity of ZnO nanosheets under natural sunlight

    SciTech Connect

    Khokhra, Richa; Kumar, Rajesh

    2015-05-15

    A facile room temperature, aqueous solution-based chemical method has been adopted for large-scale synthesis of Fe doped ZnO nanosheets. The XRD and SEM results reveal the as-synthesized products well crystalline and accumulated by large amount of interweave nanosheets, respectively. Energy dispersive spectroscopy data confirmed Fe doping of the ZnO nanosheets with a varying Fe concentration. The photoluminescence spectrum reveals a continuous suppression of defect related emissions intensity by increasing the concentration of the Fe ion. A photocatalytic activity using these samples under sunlight irradiation in the mineralization of methylene blue dye was investigated. The photocatalytic activity of Fe doped ZnO nanosheets depends upon the presence of surface oxygen vacancies.

  10. Concentration dependent effects of commonly used pesticides on activation versus inhibition of the quince (Cydonia Oblonga) polyphenol oxidase.

    PubMed

    Fattouch, Sami; Raboudi-Fattouch, Faten; Ponce, José Vicente Gil; Forment, Josep Vicent; Lukovic, Dunja; Marzouki, Nejib; Vidal, Daniel Ramón

    2010-03-01

    Polyphenol oxidase (PPO) catalyzes the oxidation of o-diphenols to their respective quinones which undergo autopolymerization and form dark pigments. The interaction of PPO with various substrates and effectors remains the focus of intensive investigations due to the enzyme's key role in pigments biosynthesis including animal melanogenesis and fruit/fungi enzymatic browning. In this study, the effect of a range of commonly used pesticides on the enzyme activity has been evaluated using the purified quince (Cydonia oblonga Miller) PPO. The biochemical analysis showed that, in the presence of high pesticide concentrations, the enzyme was competitively inhibited, particularly with benomyl, carbaryl, deltamethrine and parathion methyl for which inhibition constants (K(i)) were 8.3, 5.7, 12 and 4 microM, respectively. At lower pesticide concentrations (2-10 microM), however, the catecholase activity was significantly activated (p<0.01), suggesting a homotropic behavior of these chemical compounds. Furthermore, the use of in silico structure-based analyses, known as computational docking, highlighted the nature of the PPO-pesticides interactions and confirmed the in vitro observations. Catechol substrate and parathion methyl inhibitor showed lower total energy scores of -120.06 and -117.4 3 kcal mol(-1), indicating that these ligands had higher PPO-binding affinities. The obtained data bring to light new pesticide functional features of great interest in the medicinal, agro-chemical and environmental circles.

  11. A survey of gross alpha and beta activity concentrations in groundwater from Katsina area of Northern Nigeria.

    PubMed

    Muhammad, B G; Jaafar, M S; Akpa, T C

    2010-09-01

    Stratified sampling procedure was employed to collect a total of 40 samples; 2 from each stratum, measuring an approximate dimension of 3.25 km(2) of the actual sample site. Appropriate volumes were then evaporated and transferred into clean stainless steel planchets (ISO 9696 and ISO 9697). An eight channel gas-flow proportional counting system connected to a microprocessor loaded with a spreadsheet programme (Quarttro-Pro) and graphic programme (Multiplan) initially calibrated for efficiency was employed to count the background and the prepared samples. A mean efficiency of 33.44 and 41.24 % for the respective alpha and beta sources was obtained. A low background activity was also observed with a mean of 0.165 Bq for alpha and 1.119 Bq for beta. The gross alpha and beta activity concentrations in the water were found to range from 80 +/- 0.05 to 2300 +/- 0.41 Bq m(-3) and 120 +/- 0.08 to 4970 +/- 0.78 Bq m(-3), respectively. This clearly indicate areas of elevated alpha and beta activity concentrations of 37.5 and 47.5 %, respectively when compared with the International Commission for Radiological Protection (1991) maximum acceptable values of 500 Bq m(-3) for alpha and 1000 Bq m(-3) for beta.

  12. ZnO nanoparticles obtained by pulsed laser ablation and their composite with cotton fabric: Preparation and study of antibacterial activity

    NASA Astrophysics Data System (ADS)

    Svetlichnyi, Valery; Shabalina, Anastasiia; Lapin, Ivan; Goncharova, Daria; Nemoykina, Anna

    2016-05-01

    A simple deposition method was used to prepare a ZnO/cotton fabric composite from water and ethanol dispersions of ZnO nanoparticles obtained by the pulsed laser ablation method. The structure and composition of the nanoparticles from dispersions and as-prepared composites were studied using electron microscopy, X-ray diffraction, and spectroscopy. The nanoparticles and composite obtained exhibited antibacterial activity to three different pathogenic microorganisms-Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. An attempt to understand a mechanism of bactericidal effect of ZnO nanoparticles was made. It was shown that zinc ions and hydrogen peroxide were not responsible for antibacterial activity of the particles and the composite, and surface properties of nanoparticles played an important role in antibacterial activity of zinc oxide. The proposed composite is a promising material for use as an antibacterial bandage.

  13. Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity

    SciTech Connect

    Qin Xujun; Hudson, Laurie G.; Liu Wenlan; Timmins, Graham S.; Liu Kejian

    2008-10-01

    Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we tested the hypothesis that low concentrations of arsenic could inhibit PAPR-1 activity and so exacerbate levels of ultraviolet radiation (UVR)-induced DNA strand breaks. HaCat cells were treated with arsenite and/or UVR, and then DNA strand breaks were assessed by comet assay. Low concentrations of arsenite ({<=} 2 {mu}M) alone did not induce significant DNA strand breaks, but greatly enhanced the DNA strand breaks induced by UVR. Further studies showed that 2 {mu}M arsenite effectively inhibited PARP-1 activity. Zinc supplementation of arsenite-treated cells restored PARP-1 activity and significantly diminished the exacerbating effect of arsenite on UVR-induced DNA strand breaks. Importantly, neither arsenite treatment, nor zinc supplementation changed UVR-triggered reactive oxygen species (ROS) formation, suggesting that their effects upon UVR-induced DNA strand breaks are not through a direct free radical mechanism. Combination treatments of arsenite with PARP-1 inhibitor 3-aminobenzamide or PARP-1 siRNA demonstrate that PARP-1 is the target of arsenite. Together, these findings show that arsenite at low concentration exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity, which may represent an important mechanism underlying the co-carcinogenicity of arsenic.

  14. Response of oxidative enzyme activities to nitrogen deposition affects soil concentrations of dissolved organic carbon

    USGS Publications Warehouse

    Waldrop, M.P.; Zak, D.R.

    2006-01-01

    Recent evidence suggests that atmospheric nitrate (NO3- ) deposition can alter soil carbon (C) storage by directly affecting the activity of lignin-degrading soil fungi. In a laboratory experiment, we studied the direct influence of increasing soil NO 3- concentration on microbial C cycling in three different ecosystems: black oak-white oak (BOWO), sugar maple-red oak (SMRO), and sugar maple-basswood (SMBW). These ecosystems span a broad range of litter biochemistry and recalcitrance; the BOWO ecosystem contains the highest litter lignin content, SMRO had intermediate lignin content, and SMBW leaf litter has the lowest lignin content. We hypothesized that increasing soil solution NO 3- would reduce lignolytic activity in the BOWO ecosystem, due to a high abundance of white-rot fungi and lignin-rich leaf litter. Due to the low lignin content of litter in the SMBW, we further reasoned that the NO3- repression of lignolytic activity would be less dramatic due to a lower relative abundance of white-rot basidiomycetes; the response in the SMRO ecosystem should be intermediate. We increased soil solution NO3- concentrations in a 73-day laboratory incubation and measured microbial respiration and soil solution dissolved organic carbon (DOC) and phenolics concentrations. At the end of the incubation, we measured the activity of ??-glucosidase, N-acetyl-glucosaminidase, phenol oxidase, and peroxidase, which are extracellular enzymes involved with cellulose and lignin degradation. We quantified the fungal biomass, and we also used fungal ribosomal intergenic spacer analysis (RISA) to gain insight into fungal community composition. In the BOWO ecosystem, increasing NO 3- significantly decreased oxidative enzyme activities (-30% to -54%) and increased DOC (+32% upper limit) and phenolic (+77% upper limit) concentrations. In the SMRO ecosystem, we observed a significant decrease in phenol oxidase activity (-73% lower limit) and an increase in soluble phenolic concentrations

  15. The application of constant recycle solids concentration in activated sludge process.

    PubMed

    Bonotan-Dura, F M; Yang, P Y

    1976-02-01

    The applicability of the model derived by Ramanathan and Gaudy (Biotechnol. Bioeng., 11, 207, (1969)) for completely mixed activated sludge treatment holding the recycle solids concentration as a system constant was investigated using an actual industrial organic wastewater. Short-term experiments were conducted at various dilution rates (1/8, 1/6, 1/4, 1/2, 1/1.5 hr-1) for two recycle solids concentration values (5000 and 7000 mg/liter). The influent substrate concentration was maintained at 1000 mg/liter COD and the hydraulic recycle ratio- alpha, was kept at 0.3. It was found that for bottling plant (Pepsi Cola) wastewaters, a steady state with respect to reactor biological solids and effluent COD, at different dilution rates, could be attained, lending experimental evidence to the assumption that a steady state could be reached in developing the model and also affecting the applicability of the model in industrial organic wastewater. The reactor biological solids and effluent COD calculated from the model closely agreed with the observed values at dilution rates lower than 0.5 hr-1. Operation at dilution rates higher than 0.5 hr-1 will washout the biological solids from the reactor and the recycle substrate concentration will be apparent if the concentration of XR were not increased.

  16. Comparison of digoxin concentration in plastic serum tubes with clot activator and heparinized plasma tubes

    PubMed Central

    Dukić, Lora; Šimundić, Ana-Maria; Malogorski, Davorin

    2014-01-01

    Introduction: Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration. Materials and methods: Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot. Results: Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = −0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error. Conclusion: Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration. PMID:24627723

  17. Quantifying the 3D Odorant Concentration Field Used by Actively Tracking Blue Crabs

    NASA Astrophysics Data System (ADS)

    Webster, D. R.; Dickman, B. D.; Jackson, J. L.; Weissburg, M. J.

    2007-11-01

    Blue crabs and other aquatic organisms locate food and mates by tracking turbulent odorant plumes. The odorant concentration fluctuates unpredictably due to turbulent transport, and many characteristics of the fluctuation pattern have been hypothesized as useful cues for orienting to the odorant source. To make a direct linkage between tracking behavior and the odorant concentration signal, we developed a measurement system based the laser induced fluorescence technique to quantify the instantaneous 3D concentration field surrounding actively tracking blue crabs. The data suggest a correlation between upstream walking speed and the concentration of the odorant signal arriving at the antennule chemosensors, which are located near the mouth region. More specifically, we note an increase in upstream walking speed when high concentration bursts arrive at the antennules location. We also test hypotheses regarding the ability of blue crabs to steer relative to the plume centerline based on the signal contrast between the chemosensors located on their leg appendages. These chemosensors are located much closer to the substrate compared to the antennules and are separated by the width of the blue crab. In this case, it appears that blue crabs use the bilateral signal comparison to track along the edge of the plume.

  18. The application of constant recycle solids concentration in activated sludge process.

    PubMed

    Bonotan-Dura, F M; Yang, P Y

    1976-02-01

    The applicability of the model derived by Ramanathan and Gaudy (Biotechnol. Bioeng., 11, 207, (1969)) for completely mixed activated sludge treatment holding the recycle solids concentration as a system constant was investigated using an actual industrial organic wastewater. Short-term experiments were conducted at various dilution rates (1/8, 1/6, 1/4, 1/2, 1/1.5 hr-1) for two recycle solids concentration values (5000 and 7000 mg/liter). The influent substrate concentration was maintained at 1000 mg/liter COD and the hydraulic recycle ratio- alpha, was kept at 0.3. It was found that for bottling plant (Pepsi Cola) wastewaters, a steady state with respect to reactor biological solids and effluent COD, at different dilution rates, could be attained, lending experimental evidence to the assumption that a steady state could be reached in developing the model and also affecting the applicability of the model in industrial organic wastewater. The reactor biological solids and effluent COD calculated from the model closely agreed with the observed values at dilution rates lower than 0.5 hr-1. Operation at dilution rates higher than 0.5 hr-1 will washout the biological solids from the reactor and the recycle substrate concentration will be apparent if the concentration of XR were not increased. PMID:1252608

  19. Interplay of solvent additive concentration and active layer thickness on the performance of small molecule solar cells.

    PubMed

    Love, John A; Collins, Samuel D; Nagao, Ikuhiro; Mukherjee, Subhrangsu; Ade, Harald; Bazan, Guillermo C; Nguyen, Thuc-Quyen

    2014-11-19

    A relationship between solvent additive concentration and active layer thickness in small-molecule solar cells is investigated. Specifically, the additive concentration must scale with the amount of semiconductor material and not as absolute concentration in solution. Devices with a wide range of active layers with thickness up to 200 nm can readily achieve efficiencies close to 6% when the right concentration of additive is used.

  20. Hepatitis C virus NS3 protease is activated by low concentrations of protease inhibitors.

    PubMed

    Dahl, Göran; Arenas, Omar Gutiérrez; Danielson, U Helena

    2009-12-01

    The nonstructural protein 3 (NS3) of hepatitis C virus (HCV) is a bifunctional enzyme with a protease and a helicase functionality located in each of the two domains of the single peptide chain. There is little experimental evidence for a functional role of this unexpected arrangement since artificial single domain forms of both enzymes are catalytically competent. We have observed that low concentrations of certain protease inhibitors activate the protease of full-length NS3 from HCV genotype 1a with up to 100%, depending on the preincubation time and the inhibitor used. The activation was reduced, but not eliminated, by increased ionic strength, lowered glycerol concentration, or lowered pH. In all cases, it was at the expense of a significant loss of activity. Activation was not seen with the artificial protease domain of genotype 1b NS3 fused with a fragment of the NS4A cofactor. This truncated and covalently modified enzyme form was much less active and exhibited fundamentally different catalytic properties to the full-length NS3 protease without the fused cofactor. The most plausible explanation for the activation was found to involve a slow transition between two enzyme conformations, which differed in their catalytic ability and affinity for inhibitors. Equations derived based on this assumption resulted in better fits to the experimental data than the equation for simple competitive inhibition. The mechanism may involve an inhibitor-induced stabilization of the helicase domain in a conformation that enhances the protease activity, or an improved alignment of the catalytic triad in the protease. The proposed mnemonic mechanism and derived equations are viable for both these explanations and can serve as a basic framework for future studies of enzymes activated by inhibitors or other ligands.

  1. Bayesian Estimation of the Active Concentration and Affinity Constants Using Surface Plasmon Resonance Technology.

    PubMed

    Feng, Feng; Kepler, Thomas B

    2015-01-01

    Surface plasmon resonance (SPR) has previously been employed to measure the active concentration of analyte in addition to the kinetic rate constants in molecular binding reactions. Those approaches, however, have a few restrictions. In this work, a Bayesian approach is developed to determine both active concentration and affinity constants using SPR technology. With the appropriate prior probabilities on the parameters and a derived likelihood function, a Markov Chain Monte Carlo (MCMC) algorithm is applied to compute the posterior probability densities of both the active concentration and kinetic rate constants based on the collected SPR data. Compared with previous approaches, ours exploits information from the duration of the process in its entirety, including both association and dissociation phases, under partial mass transport conditions; do not depend on calibration data; multiple injections of analyte at varying flow rates are not necessary. Finally the method is validated by analyzing both simulated and experimental datasets. A software package implementing our approach is developed with a user-friendly interface and made freely available. PMID:26098764

  2. Effect of petrochemical sludge concentrations of changes in mutagenic activity during soil bioremediation process.

    PubMed

    Morelli, I S; Vecchioli, G I; Del Panno, M T; Painceira, M T

    2001-10-01

    The present study was performed to assess the effect of the petrochemical sludge application rate on the mutagenic activity (Ames test) of soil and the persistence of mutagenic activity during laboratory soil bioremediation process. Sludge-soil systems were prepared at four different sludge application rates (1.25, 2.5, 5, and 10% w/w). Unamended soil was used as a control. Immediately following sludge application, in the absence or presence of S9, a linear correlation between sludge application rates and mutagenicity was found but differed significantly (p < 0.05) from the control system only at higher application rates (5 and 10% w/w). The direct mutagenicity of all systems decreases during the bioremediation process, and after a year of treatment only the 10% system induced a mutagenic response that was significantly different from the control system. On the other hand, an initial increase of the indirect mutagenicity was observed at all application rates. The time required for observing this increase was inversely proportional to the initial sludge concentration. After a year of treatment, the indirect mutagenicity of all sludge-amended soils was not significantly different but was significantly different from the unamended soils. The persistence of the direct mutagenic activity of the sludge-amended soils was related to the sludge concentration, whereas the indirect mutagenic persistence was related to the relationship between easily degradable hydrocarbons and polynuclear aromatic hydrocarbons concentration and independent from the initial application rate. PMID:11596747

  3. Effect of petrochemical sludge concentrations of changes in mutagenic activity during soil bioremediation process.

    PubMed

    Morelli, I S; Vecchioli, G I; Del Panno, M T; Painceira, M T

    2001-10-01

    The present study was performed to assess the effect of the petrochemical sludge application rate on the mutagenic activity (Ames test) of soil and the persistence of mutagenic activity during laboratory soil bioremediation process. Sludge-soil systems were prepared at four different sludge application rates (1.25, 2.5, 5, and 10% w/w). Unamended soil was used as a control. Immediately following sludge application, in the absence or presence of S9, a linear correlation between sludge application rates and mutagenicity was found but differed significantly (p < 0.05) from the control system only at higher application rates (5 and 10% w/w). The direct mutagenicity of all systems decreases during the bioremediation process, and after a year of treatment only the 10% system induced a mutagenic response that was significantly different from the control system. On the other hand, an initial increase of the indirect mutagenicity was observed at all application rates. The time required for observing this increase was inversely proportional to the initial sludge concentration. After a year of treatment, the indirect mutagenicity of all sludge-amended soils was not significantly different but was significantly different from the unamended soils. The persistence of the direct mutagenic activity of the sludge-amended soils was related to the sludge concentration, whereas the indirect mutagenic persistence was related to the relationship between easily degradable hydrocarbons and polynuclear aromatic hydrocarbons concentration and independent from the initial application rate.

  4. Concentration of enteric virus indicator from seawater using granular activated carbon.

    PubMed

    Cormier, Jiemin; Gutierrez, Miguel; Goodridge, Lawrence; Janes, Marlene

    2014-02-01

    Fecal contamination of shellfish growing seawater with enteric viruses is often associated with human outbreaks of gastroenteritis. Male specific bacteriophage MS2 is correlated with those of enteric viruses in a wide range of water environments and has been used widely as a surrogate for pathogenic waterborne viruses. Since viruses in contaminated water are usually at low levels, the development of methods to concentrate viruses from water is crucial for detection purposes. In the present study, granular activated carbon was evaluated for concentration of MS2 from artificial seawater, and different parameters of the seawater were also compared. Recovery of MS2 from warm seawater (37°C) was found to be significantly greater than from cold seawater (4 and 20°C), and even greater than from fresh water (4, 20 and 37°C); the difference between seawater and fresh water became less profound when the temperatures of both were below 37°C. Although not of statistical significance, recovery of MS2 from low salinity seawater (10 and 20 parts per thousand, ppt) was greater than from high salinity seawater (30 and 40ppt). One gram of granular activated carbon was able to extract 6-log plaque forming units (PFU) of MS2 from 500ml seawater at 37°C. This study demonstrated that granular activated carbon can concentrate an enteric virus indicator from shellfish growing seawater effectively.

  5. Bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.

    PubMed

    Cebrián, G; Arroyo, C; Mañas, P; Condón, S

    2014-10-01

    The NaCl MNICs (maximum non-inhibitory concentrations) and MICs (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. The influence of prior growth conditions on the MNICs and MICs was also evaluated. No significant changes on the MNICs and MICs were found among the strains studied within each species. Among all factors investigated, only growth phase -for Gram-negatives- and growth at high NaCl concentrations led to a change in the NaCl MNICs. Species could be classified depending on its NaCl MNICs and MICs (in decreasing order) as follows: Staphylococcus aureus, Listeria monocytogenes, Cronobacter sakazakii, Enterococcus faecium, Escherichia coli and Salmonella Typhimurium. Similar results were obtained for KCl, LiCl, and sodium acetate, but not for the remaining solutes investigated (sucrose, glycerol, MgCl2 and CaCl2). Results obtained indicate that, in general, Gram-negatives showed lower MNICs and MICs than Gram-positives for all the solutes, S. aureus being the most solute tolerant microorganism. When compared on a molar basis, glycerol showed the highest MNICs and MICs for all the microorganisms -except for S. aureus- and LiCl the lowest ones. NaCl MNICs and MICs were not significantly different from those of KCl when compared on a molar basis. Therefore, the inhibitory action of NaCl could not be linked to the specific action of Na(+). Results also showed that the Na(+) tolerance of some species was Cl(-) dependent whereas for others it was not, and that factors others than aw-decrease contribute to the inhibitory action of LiCl, CaCl2 and MgCl2.

  6. Studies on Thorium Adsorption Characteristics upon Activated Titanium Hydroxide Prepared from Rosetta Ilmenite Concentrate

    SciTech Connect

    Gado, M Zaki, S

    2016-01-01

    The titanium hydroxide prepared from Rosetta ilmenite concentrate has been applied for Th (IV) adsorption from its acid aqueous solutions. The prepared hydroxide is first characterized by both Fourier transform infrared (FT-IR) spectrum and thermogravimetric analysis. The relevant factors affecting the adsorption process have been studied. The obtained equilibrium data fits well with the Langmuir isotherm rather than Freundlich isotherm, while the adsorption kinetic data follow the pseudo-second order model. The different thermodynamic parameters have also been calculated and indicate that the adsorption process is spontaneous.

  7. Study of the adsorption of Cd and Zn onto an activated carbon: Influence of pH, cation concentration, and adsorbent concentration

    SciTech Connect

    Seco, A.; Marzal, P.; Gabaldon, C.; Ferrer, J.

    1999-06-01

    The single adsorption of Cd and Zn from aqueous solutions has been investigated on Scharlau Ca 346 granular activated carbon in a wide range of experimental conditions: pH, metal concentration, and carbon concentration. The results showed the efficiency of the activated carbon as sorbent for both metals. Metal removals increase on raising the pH and carbon concentration, and decrease on raising the initial metal concentration. The adsorption processes have been modeled using the surface complex formation (SCF) Triple Layer Model (TLM). The adsorbent TLM parameters were determined. Modeling has been performed assuming a single surface bidentate species or an overall surface species with fractional stoichiometry. The bidentate stoichiometry successfully predicted cadmium and zinc removals in all the experimental conditions. The Freundlich isotherm has been also checked.

  8. Coat Protein Activation of Alfalfa Mosaic Virus Replication Is Concentration Dependent

    PubMed Central

    Guogas, Laura M.; Laforest, Siana M.; Gehrke, Lee

    2005-01-01

    Alfalfa mosaic virus (AMV) and ilarvirus RNAs are infectious only in the presence of the viral coat protein; therefore, an understanding of coat protein's function is important for defining viral replication mechanisms. Based on in vitro replication experiments, the conformational switch model states that AMV coat protein blocks minus-strand RNA synthesis (R. C. Olsthoorn, S. Mertens, F. T. Brederode, and J. F. Bol, EMBO J. 18:4856-4864, 1999), while another report states that coat protein present in an inoculum is required to permit minus-strand synthesis (L. Neeleman and J. F. Bol, Virology 254:324-333, 1999). Here, we report on experiments that address these contrasting results with a goal of defining coat protein′s function in the earliest stages of AMV replication. To detect coat-protein-activated AMV RNA replication, we designed and characterized a subgenomic luciferase reporter construct. We demonstrate that activation of viral RNA replication by coat protein is concentration dependent; that is, replication was strongly stimulated at low coat protein concentrations but decreased progressively at higher concentrations. Genomic RNA3 mutations preventing coat protein mRNA translation or disrupting coat protein's RNA binding domain diminished replication. The data indicate that RNA binding and an ongoing supply of coat protein are required to initiate replication on progeny genomic RNA transcripts. The data do not support the conformational switch model's claim that coat protein inhibits the initial stages of viral RNA replication. Replication activation may correlate with low local coat protein concentrations and low coat protein occupancy on the multiple binding sites present in the 3′ untranslated regions of the viral RNAs. PMID:15827190

  9. Effects of CO/sub 2/ concentration on rubisco amount, activity, and photosynthesis in soybean leaves

    SciTech Connect

    Campbell, W.J.; Allen, L.H. Jr.; Bowes, G.

    1987-04-01

    Soybeans were grown at CO/sub 2/ concentrations ranging from 160 to 990 ..mu..l L/sup -1/ in outdoor chambers receiving natural sunlight. Leaf soluble protein and total rubisco activity decreased with increasing growth CO/sub 2/, when expressed on a dry weight basis, but no decrease occurred on an area basis. On an area basis, leaf photosynthetic rates of plants grown at 330 and 660 ..mu..l CO/sub 2/ L/sup -1/, and measured over a range of intercellular CO/sub 2/ of 50 to 680 ..mu..l CO/sub 2/ L/sup -1/, were always greater in the high CO/sub 2/ grown plants. Rubisco content (percent of soluble protein) and total activity (soluble protein basis), remained unchanged over the range of growth CO/sub 2/. Since rubisco content and total activity per m/sup 2/ were independent of growth CO/sub 2/ concentration, the enhanced rate of photosynthesis of leaves grown at high CO/sub 2/ was apparently not due to an increase in rubisco amount or activity. Soybean grown at high CO/sub 2/ has an extra palisade cell layer per unit leaf area. Thus, the greater photosynthetic rates of high CO/sub 2/ grown leaves may result from an enhanced ability of CO/sub 2/ to gain access to rubisco via increased total mesophyll cell surface area.

  10. Effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration on canine plasma samples

    PubMed Central

    Casella, Stefania; Giannetto, Claudia; Giudice, Elisabetta

    2010-01-01

    The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog. PMID:20458152

  11. Tracking Dissolved Methane Concentrations near Active Seeps and Gas Hydrates: Sea of Japan.

    NASA Astrophysics Data System (ADS)

    Snyder, G. T.; Aoki, S.; Matsumoto, R.; Tomaru, H.; Owari, S.; Nakajima, R.; Doolittle, D. F.; Brant, B.

    2015-12-01

    A number of regions in the Sea of Japan are known for active gas venting and for gas hydrate exposures on the sea floor. In this investigation we employed several gas sensors mounted on a ROV in order to determine the concentrations of dissolved methane in the water near these sites. Methane concentrations were determined during two-second intervals throughout each ROV deployment during the cruise. The methane sensor deployments were coupled with seawater sampling using Niskin bottles. Dissolved gas concentrations were later measured using gas chromatography in order to compare with the sensor results taken at the same time. The observed maximum dissolved methane concentrations were much lower than saturation values, even when the ROV manipulators were in contact with gas hydrate. Nonetheless, dissolved concentrations did reach several thousands of nmol/L near gas hydrate exposures and gas bubbles, more than two orders of magnitude over the instrumental detection limits. Most of the sensors tested were able to detect dissolved methane concentrations as low as 10 nmol/L which permitted detection when the ROV approached methane plume sites, even from several tens of meters above the sea floor. Despite the low detection limits, the methane sensors showed variable response times when returning to low-background seawater (~5nM). For some of the sensors, the response time necessary to return to background values occurred in a matter of minutes, while for others it took several hours. Response time, as well as detection limit, should be an important consideration when selecting methane sensors for ROV or AUV investigations. This research was made possible, in part, through funding provided by the Japanese Ministry of Economy, Trade and Industry (METI).

  12. Activity patterns, blood lactate concentrations and ratings of perceived exertion during a professional singles tennis tournament

    PubMed Central

    Mendez‐Villanueva, Alberto; Fernandez‐Fernandez, Jaime; Bishop, David; Fernandez‐Garcia, Benjamin; Terrados, Nicolas

    2007-01-01

    Objective To examine the game characteristics and physiological (ie, blood lactate concentration) and perceptual (ie, rating of perceived exertion, RPE) responses during actual tennis competition in professional performers. Methods Eight trained and internationally ranked (Association of Tennis Professionals rankings) male tennis players were studied during singles matches (best of three sets) played on an outdoor clay court surface during a professional, invitational tournament. Blood lactate concentrations (n = 53) and RPE (n = 113) were determined at selected changeovers during the game. The variables describing the characteristics of the matches, (a) duration of rallies (DRs); (b) rest time (RT); (c) effective playing time (EPT); and (d) shots per rally (SR), were determined from video recordings. Results The mean (SD) values for the match‐play activity variables were DR 7.5 (7.3) s, RT 16.2 (5.2) s, EPT 21.5 (4.9%), SR 2.7 (2.2) shots. Average blood lactate concentration and RPE values were 3.8 (2.0) mmol/l and 13 (2). Blood lactate concentrations and RPE values were significantly higher (p<0.01) in service games than in receiving games. Both blood lactate concentration and RPE values were significantly correlated with SR and DR (r = 0.80 to 0.28; p<0.001). Conclusions Blood lactate concentrations and RPE were found to be influenced by the characteristics of the match and the playing situation (ie, serving or returning). These specific situations might be used to alter the overload training stimulus during tennis on‐court practice. PMID:17237121

  13. Ascitic fluid gamma interferon concentrations and adenosine deaminase activity in tuberculous peritonitis.

    PubMed Central

    Sathar, M A; Simjee, A E; Coovadia, Y M; Soni, P N; Moola, S A; Insam, B; Makumbi, F

    1995-01-01

    The gamma interferon (gamma-IFN) concentration and the adenosine deaminase (ADA) activity were evaluated in 30 patients with tuberculous peritonitis, 21 patients with ascites due to a malignant disorder, and 41 patients with cirrhosis. The gamma-IFN concentrations were significantly higher (p < 0.0001) in tuberculous peritonitis patients (mean: 6.70 U/ml) than in the malignant (mean: 3.10 U/ml) and cirrhotic (mean: 3.08 U/ml) groups. Use of a cut off value of > or = 3.2 U/ml gave the assay a sensitivity of 93% (25 of 27), a specificity of 98% (54 of 55), positive (P+) and negative (P-) predictive values of 96% and a test accuracy of 96%. The ADA activity was significantly (p < 0.0001) higher in the tuberculous peritonitis group (mean: 101.84 U/l) than in the control groups (cirrhosis (mean: 13.49 U/l) and malignancy (mean: 19.35 U/l)). A cut off value of > 30 U/l gave the ADA test a sensitivity of 93% (26 of 28) a specificity of 96% (51 of 53), a (P+) value of 93%, a (P-) value of 96%, and a test accuracy of 95%. There was a significant (p < 0.0001) correlation (r = 0.72) between ADA activity and gamma-IFN values in patients with tuberculous peritonitis. These results show that a high concentration of gamma-IFN in ascitic fluid is as valuable as the ADA activity in the diagnosis of tuberculous peritonitis. Both are rapid non-invasive diagnostic tests for tuberculous peritonitis. PMID:7698702

  14. Radiocaesium activity concentrations in potatoes in Croatia after the Chernobyl accident and dose assessment.

    PubMed

    Franić, Zdenko; Petrinec, Branko; Marović, Gordana; Franić, Zrinka

    2007-02-01

    Systematic investigations of (137)Cs and (134)Cs activity concentrations in potatoes (Solanum tuberosum) for the post-Chernobyl period (1986-2005) in the Republic of Croatia are summarized. The correlation between (137)Cs activity concentrations in fallout and potatoes, has been found to be very good, the correlation coefficient being r = 0.88 with P(t) < 0.001 for 18 degrees of freedom. As the radiocaesium levels in potatoes decreased exponentially, the mean residence time of (137)Cs in potatoes was estimated by fitting the measured activity concentrations to the exponential curve. The mean residence time was found to be 6.8 +/- 1.1 years, the standard deviation being estimated by the Monte Carlo simulations. The initial observed (134)Cs:(137)Cs activity ratio in potatoes has been found to be quite variable, but slightly lesser than the theoretically predicted value of 0.5, calculated by applying the known inventory of these radionuclides in the Chernobyl reactor to the equation for the differential radioactive decay. This can be explained by presence of the pre-Chernobyl (137)Cs in soil that originated from nuclear fallout. The annual effective doses received by (134)Cs and (137)Cs intake due to consumption of potatoes estimated for an adult member of the Croatian population were found to be very small, as the per caput Dose for the entire 1986-2005 period was calculated to be about 2.9 microSv, (134)Cs accounting approximately for 1/3 of the entire dose. Therefore, after the Chernobyl accident consumption of potatoes was not the critical pathway for human intake of radiocaesium from the environment in Croatia.

  15. Measurements of 222Rn activity concentration in domestic water sources in Penang, northern peninsular Malaysia.

    PubMed

    Muhammad, B G; Jaafar, M S; Azhar, A R; Akpa, T C

    2012-04-01

    Measurements of (222)Rn activity concentration were carried out in 39 samples collected from the domestic and drinking water sources used in the island and mainland of Penang, northern peninsular, Malaysia. The measured activity concentrations ranged from 7.49 to 26.25 Bq l(-1), 0.49 to 9.72 Bq l(-1) and 0.58 to 2.54 Bq l(-1) in the raw, treated and bottled water samples collected, respectively. This indicated relatively high radon concentrations compared with that from other parts of the world, which still falls below the WHO recommended treatment level of 100 Bq l(-1). From this data, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn resulting from 1 y's consumption of these water were estimated to range from 0.003 to 0.048, 0.001 to 0.018 and 0.002 to 0.023 mSv y(-1), for age groups 0-1, 2-16 and >16 y, respectively. PMID:21642647

  16. Activity concentration of natural radioactive nuclides in nonmetallic industrial raw materials in Japan.

    PubMed

    Iwaoka, Kazuki; Tabe, Hiroyuki; Yonehara, Hidenori

    2014-11-01

    Natural materials such as rock, ore, and clay, containing natural radioactive nuclides are widely used as industrial raw materials in Japan. If these are high concentrations, the workers who handle the material can be unknowingly exposed to radiation at a high level. In this study, about 80 nonmetallic natural materials frequently used as industrial raw materials in Japan were comprehensively collected from several industrial companies, and the activity concentrations of (238)U series, (232)Th series and (40)K in the materials was determined by ICP-MS (inductively-coupled plasma mass spectrometer) and gamma ray spectrum analyses. Effective doses to workers handling them were estimated by using methods for dose estimation given in the RP 122. We found the activity concentrations to be lower than the critical values defined by regulatory requirements as described in the IAEA Safety Guide. The maximum estimated effective dose to workers handling these materials was 0.16 mSv y(-1), which was lower than the reference level (1-20 mSv y(-1)) for existing situation given in the ICRP Publ.103.

  17. Single-molecule imaging at high fluorophore concentrations by local activation of dye

    DOE PAGES

    Geertsema, Hylkje J.; Mangel, Walter F.; Schulte, Aartje C.; Spenkelink, Lisanne M.; McGrath, William J.; Morrone, Seamus R.; Sohn, Jungsan; Robinson, Andrew; van Oijen, Antoine M.

    2015-02-17

    Single-molecule fluorescence microscopy is a powerful approach to observe biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual, labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Then, making use ofmore » short-distance energy-transfer mechanisms, the fluorescence from only those proteins bound to their substrate are selectively activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 (IFI16) with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease (pVIc-AVP) on DNA in the presence of a background of hundreds of nM Cy5 fluorophore.« less

  18. Single-molecule imaging at high fluorophore concentrations by local activation of dye

    SciTech Connect

    Geertsema, Hylkje J.; Mangel, Walter F.; Schulte, Aartje C.; Spenkelink, Lisanne M.; McGrath, William J.; Morrone, Seamus R.; Sohn, Jungsan; Robinson, Andrew; van Oijen, Antoine M.

    2015-02-17

    Single-molecule fluorescence microscopy is a powerful approach to observe biomolecular interactions with high spatial and temporal resolution. Detecting fluorescent signals from individual, labeled proteins above high levels of background fluorescence remains challenging, however. For this reason, the concentrations of labeled proteins in in vitro assays are often kept low compared to their in vivo concentrations. Here, we present a new fluorescence imaging technique by which single fluorescent molecules can be observed in real time at high, physiologically relevant concentrations. The technique requires a protein and its macromolecular substrate to be labeled each with a different fluorophore. Then, making use of short-distance energy-transfer mechanisms, the fluorescence from only those proteins bound to their substrate are selectively activated. This approach is demonstrated by labeling a DNA substrate with an intercalating stain, exciting the stain, and using energy transfer from the stain to activate the fluorescence of only those labeled DNA-binding proteins bound to the DNA. Such an experimental design allowed us to observe the sequence-independent interaction of Cy5-labeled interferon-inducible protein 16 (IFI16) with DNA and the sliding via one-dimensional diffusion of Cy5-labeled adenovirus protease (pVIc-AVP) on DNA in the presence of a background of hundreds of nM Cy5 fluorophore.

  19. Measurements of 222Rn activity concentration in domestic water sources in Penang, northern peninsular Malaysia.

    PubMed

    Muhammad, B G; Jaafar, M S; Azhar, A R; Akpa, T C

    2012-04-01

    Measurements of (222)Rn activity concentration were carried out in 39 samples collected from the domestic and drinking water sources used in the island and mainland of Penang, northern peninsular, Malaysia. The measured activity concentrations ranged from 7.49 to 26.25 Bq l(-1), 0.49 to 9.72 Bq l(-1) and 0.58 to 2.54 Bq l(-1) in the raw, treated and bottled water samples collected, respectively. This indicated relatively high radon concentrations compared with that from other parts of the world, which still falls below the WHO recommended treatment level of 100 Bq l(-1). From this data, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn resulting from 1 y's consumption of these water were estimated to range from 0.003 to 0.048, 0.001 to 0.018 and 0.002 to 0.023 mSv y(-1), for age groups 0-1, 2-16 and >16 y, respectively.

  20. Concentrations of some antibiotics in synovial fluid after oral administration, with special reference to antistaphylococcal activity.

    PubMed

    Sattar, M A; Barrett, S P; Cawley, M I

    1983-02-01

    One of 4 antibiotics with antistaphylococcal activity was given in a conventional oral dose for one day to each of 20 hospitalised patients with synovial effusion of a knee joint requiring aspiration. Serial synchronous samples of serum and synovial fluid (SF) were taken over 36 hours through indwelling cannulae. No morbidity was experienced either during or after this procedure. Satisfactory antistaphylococcal concentrations in SF were achieved with sodium fusidate (500 mg 8 hourly) and amoxycillin (250 mg 8 hourly). Cephradine (500 mg 6 hourly) frequently failed to reach the minimum inhibitory concentration for Staphylococcus aureus in the SF, and flucloxacillin (250 mg 6 hourly) was unpredictable in its penetration of the synovial space. Wide interpatient variation of both serum and SF concentrations was found. Our results indicate that sodium fusidate is an appropriate early treatment for a nonresistant staphylococcal joint infection. Amoxycillin is a suitable alternative or second antistaphylococcal drug and would also be appropriate initial therapy when the infecting organism is unknown. We strongly recommend that SF antibiotic concentrations be measured, to ensure adequate penetration of the synovial cavity, in the treatment of septic arthritis.

  1. Breast Milk Concentration of Rubidium in Lactating Mothers by Instrumental Neutron Activation Analysis Method

    PubMed Central

    Khatami, Seyedeh-Fatemeh; Parvaresh, Pouya; Parvaresh, Parviz; Madani Kouchak, Sara Sadat; Khorsandi, Jamshid

    2014-01-01

    Objective: Relatively little is known about the trace elements content of human milk from different countries. This has not been fully investigated especially among Iranian women. This study aimed to assess the concentration of Rubidium (Rb) as a poisonous trace element in transitional breast milk of lactating mothers living in Mashhad. Methods: Forty nursing mothers in early lactation 3 days to 15 days postpartum, free from any medical disorder and/or medication were randomly selected. We have applied Instrumental Neutron Activation Analysis (INAA) to assess the long-lived isotope trace element Rb in transitional milk of these economically moderate 18–39 year old Iranian women. Findings: The average concentration level of Rb was 32.176 ppm dry weight (min 8.660, max 107.210 ppm). No significant correlation was observed between Rb concentration and maternal weight and age (P=0.06, P=0.05 respectively) and newborns’ weight, age and sex (P=0.07, P=0.2, P=0.2 respectively). Conclusion: Although the Rubidium concentration found in this study is among the highest reported in the literature, it could not be compared to other studies because of differences in analytical performance, state of lactation, and unavailable reference ranges, so this finding needs further investigations. PMID:26019773

  2. Effect of zinc concentration on the activity of angiotensin converting enzyme in human plasma and serum

    SciTech Connect

    Reeves, P.G.; Carl, G.F.; Smith, D.K.; O'Dell, B.L.

    1986-03-05

    The activity of angiotensin converting enzyme is measured clinically to assist in the diagnosis of sarcoidosis and to monitor therapy with steroids, and with antihypertensive drugs that inhibit the enzyme. Even though it has been known for some time that ACE is a zinc dependent enzyme, it was discovered only recently that zinc, in addition to endogenous levels in the assay mixture, is required for maximal activity of rat serum ACE. The present experiment was designed to determine if additional zinc is required for maximal activation of ACE in plasma and serum of human subjects. Plasma or serum samples were incubated at 37/sup 0/ in a zinc-free medium, pH 7.4, containing hippurylglyclglycine as the substrate. The addition of 20 ..mu..M zinc significantly increased ACE activity in plasma (95.4 +/- 11.9 vs 192.8 +/- 24.3 U/L) and in serum (89.9 +/- 5.6 vs 195.7 +/- 9.3 U/L) compared to samples without added zinc. Enzyme activity was increased 2.4-fold when zinc was added to plasma from a patient with low plasma zinc. These data suggest that the endogenous level of zinc in the assay mixture resulting from the addition of an aliquot of plasma or serum is insufficient to obtain maximal activity of ACE. The addition of zinc to zinc deficient plasma increased ACE activity even more.

  3. Comparative mutant prevention concentration and antibacterial activity of fluoroquinolones against Escherichia coli in diarrheic buffalo calves.

    PubMed

    Beri, Supriya; Sidhu, Pritam K; Kaur, Gurpreet; Chandra, Mudit; Rampal, Satyavan

    2015-10-01

    Owing to emerging threat of antimicrobial resistance, mutant prevention concentration (MPC) is considered as an important parameter to evaluate the antimicrobials for their capacity to restrict/allow the emergence of resistant mutants. Therefore, MPCs of ciprofloxacin, enrofloxacin, levofloxacin, moxifloxacin, and norfloxacin were determined against Escherichia coli isolates of diarrheic buffalo calves. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were also established. The MICs of ciprofloxacin, enrofloxacin, levofloxacin, moxifloxacin and norfloxacin were 0·009, 0·022, 0·024, 0·028, and 0·036 μg/ml, respectively. The MBCs obtained were very close to the MICs of respective drugs that suggested a bactericidal mode of action of antimicrobials. The MPCs (μg/ml) of ciprofloxacin (4·2×MIC), moxifloxacin (4·8×MIC), and norfloxacin (5·1×MIC) were approximately equal but slightly lower than enrofloxacin (7·6×MIC) and levofloxacin (8·5×MIC) against clinical isolates of E. coli. The MPC data suggested that enrofloxacin has the potential for restricting the selection of E. coli mutants during treatment at appropriate dosing.

  4. Biokinetic models for representing the complete inhibition of microbial activity at high substrate concentrations.

    PubMed

    Alagappan, G; Cowan, R M

    2001-11-20

    This paper reintroduces the Wayman and Tseng model for representing substrate inhibition effects on specific growth rate by further documenting its potential predictive capabilities. It also introduces a modification to this model in which an Andrews inhibition function is used in place of the Monod noninhibitory substrate function. This modification better represents the relationship between specific growth rate and substrate concentration for those substrates that show Andrews type inhibition at lower substrate concentrations, rather than the Monod type noninhibitory behavior described in the model of Wayman and Tseng. Results from nonlinear, least squares regression analysis are used to evaluate the ability of these models to empirically represent experimental data (both new and from the literature). The statistical goodness of fit is evaluated by comparing the regression results against those obtained using other empirical models. Finally, possible mechanisms of toxicity responsible for the observed inhibition trends are used to further justify use of these empirical models. The dominant mechanism considered to be relevant for conceptually explaining complete inhibition at high concentrations of solvents is the deterioration of cell membrane integrity. Literature citations are used to support this argument. This work should lead to improvements in the mathematical modeling of contaminant fate and transport in the environment and in the simulation of microbial growth and organic compound biodegradation in engineered systems. PMID:11668439

  5. High Fetal Estrogen Concentrations: Correlation with Increased Adult Sexual Activity and Decreased Aggression in Male Mice

    NASA Astrophysics Data System (ADS)

    Vom Saal, Frederick S.; Grant, William M.; McMullen, Carol W.; Laves, Kurt S.

    1983-06-01

    In the house mouse (Mus musculus), fetuses may develop in utero next to siblings of the same or opposite sex. The amniotic fluid of the female fetuses contains higher concentrations of estradiol than that of male fetuses. Male fetuses that developed in utero between female fetuses had higher concentrations of estradiol in their amniotic fluid than males that were located between other male fetusesw during intrauterine development. They were also more sexually active as adults, less aggressive, and had smaller seminal vesicles than males that had developed between other male fetuses in utero. These findings raise the possibility that during fetal life circulating estrogens may interact with circulating androgens both in regulating the development of sex differences between males and females and in producing variation in phenotype among males and among females.

  6. Blood pressure, plasma renin activity and aldosterone concentrations in vegans and omnivore controls.

    PubMed

    Sanders, T A; Key, T J

    1987-06-01

    Blood pressure, plasma renin activity and the concentrations of aldosterone and cholesterol in plasma and sodium and potassium in urine (48-h collections) and nutrient intakes were determined in 22 vegans (11 male and 11 female) and omnivore controls matched for age, sex and body build. The vegan diets contained less protein, sodium, calcium and sulphur but more carbohydrate, potassium and fibre than the diets of their controls. The mean urinary potassium sodium ratio was 1.13 in the vegans compared with 0.64 in the omnivores. Plasma renin and cholesterol concentrations were lower in the male but not female vegans compared with their respective controls. Blood pressures of the vegan subjects were inside the normal range but they tended to have higher mean diastolic blood pressures than their controls.

  7. Erythrocyte L-aspartyl-L-phenylalanine hydrolase activity and plasma phenylalanine and aspartate concentrations in children consuming diets high in aspartame.

    PubMed

    Stegink, L D; Lindgren, S D; Brummel, M C; Stumbo, P J; Wolraich, M L

    1995-12-01

    A deficit of alpha-aspartyl-phenylalanine (alpha-Asp-Phe) hydrolase activity has been suggested as a cause of possible adverse effects of aspartame ingestion. Twenty-five normal preschool children and 23 school-age children described by their parents as sensitive to sugar were fed diets high in sucrose, aspartame, or saccharin for three successive 3-wk periods. Blood samples were obtained at baseline (fasting) and within the last 3 d of each dietary period (postprandial). alpha-Asp-Phe concentrations were below detection limits (0.5 mumol/L) in all plasma samples and Phe and Asp concentrations remained within normal limits, alpha-Asp-Phe hydrolase activities in baseline hemolysate samples did not differ between groups. One subject had a plasma alpha-Asp-Phe hydrolase activity > 2 SD below the mean. Despite this low activity, this subject did not show consistent cognitive or behavioral anomalies that could be linked to low hydrolase activity.

  8. Serum Malondialdehyde Concentration and Glutathione Peroxidase Activity in a Longitudinal Study of Gestational Diabetes

    PubMed Central

    Miranda, María; Muriach, María; Romero, Francisco J.; Villar, Vincent M.

    2016-01-01

    Aims The main goal of this study was to evaluate the presence of oxidative damage and to quantify its level in gestational diabetes. Methods Thirty-six healthy women and thirty-six women with gestational diabetes were studied in the three trimesters of pregnancy regarding their levels of oxidative stress markers. These women were diagnosed with diabetes in the second trimester of pregnancy. Blood glucose levels after 100g glucose tolerance test were higher than 190, 165 or 145 mg/dl, 1, 2 or 3 hours after glucose intake. Results The group of women with gestational diabetes had higher serum malondialdehyde levels, with significant differences between groups in the first and second trimester. The mean values of serum glutathione peroxidase activity in the diabetic women were significantly lower in the first trimester. In the group of women with gestational diabetes there was a negative linear correlation between serum malondialdehyde concentration and glutathione peroxidase activity in the second and third trimester. Conclusions In this observational and longitudinal study in pregnant women, the alterations attributable to oxidative stress were present before the biochemical detection of the HbA1c increase. Usual recommendations once GD is detected (adequate metabolic control, as well as any other normally proposed to these patients) lowered the concentration of malondialdehyde at the end of pregnancy to the same levels of the healthy controls. Serum glutathione peroxidase activity in women with gestational diabetes increased during the gestational period. PMID:27228087

  9. Lithium ions in nanomolar concentration modulate glycine-activated chloride current in rat hippocampal neurons.

    PubMed

    Solntseva, E I; Bukanova, J V; Kondratenko, R V; Skrebitsky, V G

    2016-03-01

    Lithium salts are successfully used to treat bipolar disorder. At the same time, according to recent data lithium may be considered as a candidate medication for the treatment of neurodegenerative disorders. The mechanisms of therapeutic action of lithium have not been fully elucidated. In particular, in the literature there are no data on the effect of lithium on the glycine receptors. In the present study we investigated the effect of Li(+) on glycine-activated chloride current (IGly) in rat isolated pyramidal hippocampal neurons using patch-clamp technique. The effects of Li(+) were studied with two glycine concentrations: 100 μM (EC50) and 500 μM (nearly saturating). Li(+) was applied to the cell in two ways: first, by 600 ms co-application with glycine through micropipette (short application), and, second, by addition to an extracellular perfusate for 10 min (longer application). Li(+) was used in the range of concentrations of 1 nM-1 mM. Short application of Li(+) caused two effects: (1) an acceleration of desensitization (a decrease in the time of half-decay, or "τ") of IGly induced by both 100 μM and 500 μM glycine, and (2) a reduction of the peak amplitude of the IGly, induced by 100 μM, but not by 500 μM glycine. Both effects were not voltage-dependent. Dose-response curves for both effects were N-shaped with two maximums at 100 nM and 1 mM of Li(+) and a minimum at 1 μM of Li(+). This complex form of dose-response may indicate that the process activated by high concentrations of lithium inhibits the process that is sensitive to low concentrations of lithium. Longer application of Li(+)caused similar effects, but in this case 1 μM lithium was effective and the dose-effect curves were not N-shaped. The inhibitory effect of lithium ions on glycine-activated current suggests that lithium in low concentrations is able to modulate tonic inhibition in the hippocampus. This important property of lithium should be considered when using this drug as a

  10. Activities of titanium in molten copper at dilute concentrations measured by solid- state electrochemical cells at 1373 K

    NASA Astrophysics Data System (ADS)

    Hoshino, H.; Shimada, T.; Yamamoto, M.; Iwase, M.

    1992-03-01

    In order to obtain the activities of titanium in molten copper at dilute concentrations, i.e., between 5 x 10-6 and 3.4 x 10-3 titanium mole fractions, liquid copper was brought into equilibrium with molten {CaCl2 + Ti2O3} slag saturated with Ti2O3 (s) at 1373 K and the equilibrium oxygen partial pressures were measured by means of a solid-oxide galvanic cell of the type Mo/Mo + MoO2/ZrO2(MgO)/(Cu + Ti)alloy + Ti2O3 + CaCl2 + Ti2O3 slag/Mo The free energy change for the dissolution of solid titanium in molten copper at infinite dilution referred to 1 wt pet was determined as Ti (s) = Ti(1 wt pet in Cu) ΔG°/J = -86,100 ± 8900 at 1373 K

  11. Effect of Direct-Current Electric Field on Enzymatic Activity and the Concentration of Laccase.

    PubMed

    Wang, Chunxing; Zhang, Huiling; Ren, Dajun; Li, Qian; Zhang, Shuqin; Feng, Tao

    2015-09-01

    This work investigates the effect of direct-current electric field on the extracellular enzymatic activity, concentration and other experimental parameters of laccase from Trametes versicolor. The results showed that laccase could significantly contribute to the change of pH at the end of graphite electrode. In addition, it increased the electrical conductivity of the water. In the experiment, the optimum pH and catalytic pH range for laccase activity were 3.0 and pH 2.5-4.0. The application of 6 V direct current showed significant effects on the laccase enzyme activity. The activity of laccase was enhanced in the anodic region, but at the same time was strongly inhibited at the cathode. The electric charge characteristics of laccase were changed when exposed to electric field, and some laccases molecules moved to the anode, which produced a slight migration phenomenon. This study is the basis of combination of laccase and electrical technology, at the same time, providing a new direction of enhancing laccase activity. Compared to immobilization, using electric field is simple, no chemical additives, and great potential.

  12. Concentric zones of active RhoA and Cdc42 around single cell wounds

    PubMed Central

    Benink, Hélène A.; Bement, William M.

    2005-01-01

    Rho GTPases control many cytoskeleton-dependent processes, but how they regulate spatially distinct features of cytoskeletal function within a single cell is poorly understood. Here, we studied active RhoA and Cdc42 in wounded Xenopus oocytes, which assemble and close a dynamic ring of actin filaments (F-actin) and myosin-2 around wound sites. RhoA and Cdc42 are rapidly activated around wound sites in a calcium-dependent manner and segregate into distinct, concentric zones around the wound, with active Cdc42 in the approximate middle of the F-actin array and active RhoA on the interior of the array. These zones form before F-actin accumulation, and then move in concert with the closing array. Microtubules and F-actin are required for normal zone organization and dynamics, as is crosstalk between RhoA and Cdc42. Each of the zones makes distinct contributions to the organization and function of the actomyosin wound array. We propose that similar rho activity zones control related processes such as cytokinesis. PMID:15684032

  13. Melanin-concentrating hormone is necessary for olanzapine-inhibited locomotor activity in male mice.

    PubMed

    Chee, Melissa J S; Douris, Nicholas; Forrow, Avery B; Monnard, Arnaud; Lu, Shuangyu; Flaherty, Stephen E; Adams, Andrew C; Maratos-Flier, Eleftheria

    2015-10-01

    Olanzapine (OLZ), an atypical antipsychotic, can be effective in treating patients with restricting type anorexia nervosa who exercise excessively. Clinical improvements include weight gain and reduced pathological hyperactivity. However the neuronal populations and mechanisms underlying OLZ actions are not known. We studied the effects of OLZ on hyperactivity using male mice lacking the hypothalamic neuropeptide melanin-concentrating hormone (MCHKO) that are lean and hyperactive. We compared the in vivo effects of systemic or intra-accumbens nucleus (Acb) OLZ administration on locomotor activity in WT and MCHKO littermates. Acute systemic OLZ treatment in WT mice significantly reduced locomotor activity, an effect that is substantially attenuated in MCHKO mice. Furthermore, OLZ infusion directly into the Acb of WT mice reduced locomotor activity, but not in MCHKO mice. To identify contributing neuronal mechanisms, we assessed the effect of OLZ treatment on Acb synaptic transmission ex vivo and in vitro. Intraperitoneal OLZ treatment reduced Acb GABAergic activity in WT but not MCHKO neurons. This effect was also seen in vitro by applying OLZ to acute brain slices. OLZ reduced the frequency and amplitude of GABAergic activity that was more robust in WT than MCHKO Acb. These findings indicate that OLZ reduced Acb GABAergic transmission and that MCH is necessary for the hypolocomotor effects of OLZ.

  14. Effect of Yeast Probiotic on Growth, Antioxidant Enzyme Activities and Malondialdehyde Concentration of Broiler Chickens.

    PubMed

    Aluwong, Tagang; Kawu, Mohammed; Raji, Moshood; Dzenda, Tavershima; Govwang, Felix; Sinkalu, Victor; Ayo, Joseph

    2013-11-06

    The aim of the study was to determine the effect of yeast probiotic on body weight, and the activities of anti-oxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and malondialdehyde (MDA) concentration of broiler chickens. The experiment was carried out on hybrid Hubbard broiler chickens (n = 200). Two-hundred day-old chicks were randomly selected and distributed into four groups of 50 day-old chicks each: Control, C, and treatment groups comprising T₁, T₂ and T₃ administered with 0.25 mL, 0.5 mL and 1.0 mL yeast probiotic, respectively. Chicks were fed a commercial starter diet for the first 28 days of age, followed by pelleted finisher diet from 29 to 42 days. Chickens in T₁ had a significantly (p < 0.01) higher body weight at 4th week of age when compared with the control. SOD activity in all treatment groups was not significantly (p > 0.05) different when compared with the control. GPx activity was significantly (p < 0.01) higher in T₁, when compared with the control. GPx activity in T₂ was higher (p < 0.01) when compared with the control. There was no significant (p > 0.05) difference in MDA level in all the treatment groups. In conclusion, administering yeast probiotic supplement increased body weight and enhanced serum anti-oxidant enzyme activities of broiler chickens.

  15. Activated charcoal filter counting for radioiodine effluent concentration determination in protein iodinations.

    PubMed

    Button, T M; Hamilton, R G

    1982-12-01

    Regulatory agencies have recently placed emphasis upon quantification of 125I released to the environment during protein iodinations at radioiodination facilities. This necessitates air sampling in order to determine the concentration of 125I in the effluent. Air sample trapping mechanisms generally employed are activated charcoal filters. Difficulty arises in quantifying the activity of 125I trapped because of the attenuation of the 125I decay photons by the charcoal. Evaluation of the activity incident upon commercially available filters using a scintillation detector and large detector source separation is considered here. It is demonstrated that the activity in the filter may be treated as an exponential distribution within an attentuating matrix. This treatment essentially adds a constant correction factor to the counting efficiency of a given geometry for a filter-affluent flow rate combination. Finally, it is shown that an approximation assuming a uniform distribution of activity produces a large error in correction factor to the counting efficiency for the filters examined. PMID:7152949

  16. Bactericidal activity of electrolyzed acid water from solution containing sodium chloride at low concentration, in comparison with that at high concentration.

    PubMed

    Kiura, Hiromasa; Sano, Kouichi; Morimatsu, Shinichi; Nakano, Takashi; Morita, Chizuko; Yamaguchi, Masaki; Maeda, Toyoyuki; Katsuoka, Yoji

    2002-05-01

    Electrolyzed strong acid water (ESW) containing free chlorine at various concentrations is becoming to be available in clinical settings as a disinfectant. ESW is prepared by electrolysis of a NaCl solution, and has a corrosive activity against medical instruments. Although lower concentrations of NaCl and free chlorine are desired to eliminate corrosion, the germicidal effect of ESW with low NaCl and free-chlorine concentrations (ESW-L) has not been fully clarified. In this study, we demonstrated that ESW-L possesses bactericidal activity against Mycobacteria and spores of Bacillus subtilis. The effect was slightly weaker than that of ESW containing higher NaCl and free-chlorine concentrations (ESW-H), but acceptable as a disinfectant. To clarify the mechanism of the bactericidal activity, we investigated ESW-L-treated Pseudomonas aeruginosa by transmission electron microscopy, a bacterial enzyme assay and restriction fragment length polymorphism pattern (RFLP) assay. Since the bacterium, whose growth was completely inhibited by ESW-L, revealed the inactivation of cytoplasmic enzyme, blebs and breaks in its outer membrane and remained complete RFLP of DNA, damage of the outer membrane and inactivation of cytoplasmic enzyme are the important determinants of the bactericidal activity.

  17. Preparation and Characterization of Nanocomposites from Whey Protein Concentrate Activated with Lycopene.

    PubMed

    Pereira, Rafaela Corrêa; de Deus Souza Carneiro, João; Borges, Soraia Vilela; Assis, Odílio Benedito Garrido; Alvarenga, Gabriela Lara

    2016-03-01

    The production and characterization of nanocomposites based on whey protein concentrate (WPC) and montmorilonite (MMT) incorporated with lycopene as a functional substance is presented and discussed as an alternative biomaterial for potential uses in foodstuff applications. A full factorial design with varying levels of MMT (0% and 2% in w/w) and lycopene (0%, 6%, and 12% in w/w) was used. Color, light transmission, film transparency, moisture, density, solubility, water vapor permeability, and antioxidant activity of the resulting materials were evaluated. Results indicated that lycopene and MMT nanoparticles were successfully included in WPC films using the casting/evaporation method. Inclusion of 2% w/w of MMT in the polymeric matrix significantly improved barrier property against water vapor. Lycopene, besides its good red coloring ability, provided to the films antioxidant activity and UV-vis light protection. These findings open a new perspective for the use of materials for bioactive packaging applications. PMID:26814439

  18. Mutagenicity studies in a tyre plant: in-vitro activity of urine concentrates and rubber chemicals.

    PubMed

    Crebelli, R; Falcone, E; Aquilina, G; Carere, A; Paoletti, A; Fabri, G

    1984-01-01

    A possible occupational contribution to urinary mutagenicity was studied in a tyre plant, by assaying concentrates of urine from 72 workmen and 23 controls for their activity in the Ames test and microtitre fluctuation test. The results show that smoking habits but not occupation are related to the appearance of a detectable urinary mutagenicity in strain TA98. A possible synergistic effect of occupation was, however, observed among tyre builders who were smokers. Mutagenicity screening of 25 rubber chemicals, of major technological relevance and used in high volume in the workplace investigated, showed that three of them are weakly active in TA98 and TA100 (tetramethylthiuram disulfide) or TA98 alone (poly-p-dinitrosobenzene and mixed diaryl-p-phenylendiamines). PMID:6400096

  19. Barley chloroplast glutamine synthetase activity is not affected by CO sub 2 -concentration

    SciTech Connect

    Avila, C.; Forde, B.; Wallsgrove, R. )

    1990-05-01

    It has been reported that when photorespiration is suppressed by raising the concentration of CO{sub 2}, the expression of the chloroplast glutamine synthetase (GS2) gene in pea leaves is reduced (Plant Cell, 1, 241). We have examined this effect in barley (Hordeum vulgare), and confirm that plants grown continuously in 0.8% CO{sub 2}, or transferred to such conditions after growth in air, appear to have a reduced GS2 mRNA abundance. However, we were unable to detect any significant difference in the extractable GS2 activity, or any change in amount of GS2 protein (judged by Western blots). Whatever controls are operating on gS2 mRNA expression in response to changes is external CO{sub 2}, they do not affect the activity or amount of the enzyme in barley.

  20. Preparation and Characterization of Nanocomposites from Whey Protein Concentrate Activated with Lycopene.

    PubMed

    Pereira, Rafaela Corrêa; de Deus Souza Carneiro, João; Borges, Soraia Vilela; Assis, Odílio Benedito Garrido; Alvarenga, Gabriela Lara

    2016-03-01

    The production and characterization of nanocomposites based on whey protein concentrate (WPC) and montmorilonite (MMT) incorporated with lycopene as a functional substance is presented and discussed as an alternative biomaterial for potential uses in foodstuff applications. A full factorial design with varying levels of MMT (0% and 2% in w/w) and lycopene (0%, 6%, and 12% in w/w) was used. Color, light transmission, film transparency, moisture, density, solubility, water vapor permeability, and antioxidant activity of the resulting materials were evaluated. Results indicated that lycopene and MMT nanoparticles were successfully included in WPC films using the casting/evaporation method. Inclusion of 2% w/w of MMT in the polymeric matrix significantly improved barrier property against water vapor. Lycopene, besides its good red coloring ability, provided to the films antioxidant activity and UV-vis light protection. These findings open a new perspective for the use of materials for bioactive packaging applications.

  1. Measurement of activity concentrations of natural radionuclides in the topsoil of IITA Ibadan by gamma-ray spectrometry.

    PubMed

    Okeyode, I C; Farai, I P

    2007-09-01

    The activity concentrations of the natural radionuclides in the soils at the International Institute of Tropical Agriculture, (IITA), Idi-Ose, Moniya, Ibadan, Nigeria were investigated using a NaI (Tl) scintillation detector coupled with a Canberra series 10 plus multichannel analyser as the detecting device for gamma scintillation spectroscopy. The whole area was divided into grids and soil samples were collected from the points of intersection of the grids. The average activity concentrations obtained for the three radionuclides (40K, 238U and 232Th) were 180.08 +/- 90.54 Bq kg(-1) for 40K, 8.901 +/- 5.063 Bq kg(-1) for 238U and 11.01 +/- 7.686 Bq kg(-1) for 232Th. The average values of the absorbed dose rate for each radionuclide were found to be 7.33 nGy h(-1) for 232Th, 7.55 nGy h(-1) for 40K and 3.82 nGy h(-1) for 238U. The average (baseline) of the total absorbed dose rate was found to be 18.72 +/- 8.11 nGy h(-1). The baseline average outdoor annual effective dose equivalent at IITA due to the concentrations of the radionuclides was found to be 22.95 +/- 9.94 microSv y(-1). This value is low compared to the world average of 70 microSv y(-1) specified by UNSCEAR for an outdoor effective dose. Hence the probability of occurrence of any of the health effects of radiation is low.

  2. How far does phospholipase C activity depend on the cell calcium concentration? A study in intact cells.

    PubMed Central

    Renard, D; Poggioli, J; Berthon, B; Claret, M

    1987-01-01

    The dependence of phospholipase C activity on the cytosolic Ca2+ concentration ([Ca2+]i) was studied in intact liver cells treated with the Ca2+-mobilizing hormone vasopressin, or not so treated. Phospholipase C (PLC) activity was estimated from the formation of [3H]inositol trisphosphate (InsP3) and the degradation of [3H]phosphatidylinositol 4,5-bisphosphate (PtdInsP2). The [Ca2+]i of the cells was clamped from 29 to 1130 nM by quin2 loading. This wide concentration range was obtained by loading the hepatocytes with a high concentration of the Ca2+ indicator in low-Ca2+ medium or by using the Ca2+ ionophore ionomycin in medium containing Ca2+. In resting cells, in which [Ca2+]i was 193 nM, treatment with 0.1 microM-vasopressin which stimulates liver PLC maximally, tripled InsP3 content and raised [Ca2+]i to 2 microM within 15 s. Lowering [Ca2+]i partially decreased cell InsP3 content as well as the ability of vasopressin to stimulate InsP3 formation maximally. At 29 nM, the lowest Ca2+ concentration obtained in isolated liver cells, basal InsP3 content was 64% of that measured in control cells. Addition of vasopressin no longer affected [Ca2+]i, but significantly increased InsP3 by 200%, although less than in the controls (300%). The maintenance of the greater part of the PLC response at constant [Ca2+]i indicated that, in the liver, InsP3 formation does not result from an increase in [Ca2+]i. The effects of lowering [Ca2+]i were reversible. When low cell [Ca2+]i was restored to a normal value, resting InsP3 content and the ability of vasopressin to stimulate InsP3 formation maximally by 300% were also restored. Raising [Ca2+]i from 193 to 1130 nM had little effect on the InsP3 content or the vasopressin-mediated increase in InsP3. In agreement with the stimulation of PLC activity by vasopressin, cell [3H]PtdInsP2 and total PtdInsP2 were degraded by application of this hormone for 15 s. In contrast, when [Ca2+]i was lowered to 29 nM, basal [3H]PtdInsP2 and total

  3. Activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K in brands of fertilisers used in Nigeria.

    PubMed

    Jibiri, N N; Fasae, K P

    2012-01-01

    The activity concentration of naturally occurring radionuclides ⁴⁰K, ²²⁶Ra and ²³²Th have been measured in different brands of fertiliser samples sold to farmers in retail markets in six commercial cities in southwestern Nigeria. Gamma ray spectroscopy was employed in the measurements of these radionuclides. The results of measurements showed that the average activity concentration of ⁴⁰K in the nitrogen, phosphorus and potassium fertilisers across the cities varied from 3972.0 ± 416.9 to 5089.3 ± 111.3 Bq kg⁻¹, 9.9 ± 7.3 to 450.6 ± 14.3 Bq kg⁻¹ for ²²⁶Ra, while for ²³²Th it varied from less than lower limit of detection to 15.1 ± 2.8 Bq kg⁻¹. The activity concentrations of ⁴⁰K, ²²⁶Ra and ²³²Th in single super phosphate (SSP) fertilisers and phosphate rocks were also determined. However, high activity concentrations of ²²⁶Ra were obtained in the SSP fertiliser and phosphate rocks and in particular, two brands of fertilisers from ITL/TAK and F & C companies. The values of the activity concentration of the radionuclides in the brands of fertilisers used in Nigeria are within the range of values reported in several other countries except ⁴⁰K. PMID:21355005

  4. Impact of microbial growth inhibition and proteolytic activity on the stability of a new formulation containing a phytate-degrading enzyme obtained from mushroom.

    PubMed

    Spier, Michele R; Siepmann, Francieli B; Staack, Larissa; Souza, Priscila Z; Kumar, Vikas; Medeiros, Adriane B P; Soccol, Carlos R

    2016-10-01

    The development of stable enzymes is a key issue in both the food and feed industries. Consequently, the aim of the current study is to evaluate the impact of various additives (sodium chloride, sodium citrate, mannitol, methylparaben, polyethylene glycol 3350, ethylenediaminetetraacetic acid disodium salt, and a serine protease inhibitor) on the stability of a mushroom phytase produced by solid-state cultivation and recovery. Also observed was the effect of the additives on microbial growth inhibition by monitoring both the change in optical density over 30 days of storage and proteolytic activity. Initially, eight experimental formulations were prepared along with a control. After screening, a 3(2) factorial design was applied to define suitable concentrations of the selected additives. Among the eight formulations tested, the formulation containing NaCl, PEG 3350, and methylparaben retained all of the initial phytase activity after 50 days of storage, with no detected interference from protease activity. Sodium citrate, a metal chelation agent, presented the unusual effect of reducing protease activity in the formulations. Although all formulations presented better phytase stability when compared to the control, NaCl and PEG were both able to prolong the stability of the enzyme activity and also to inhibit microbial growth during storage, making them favorable for application as food and feed additives.

  5. Optimisation of concentrating solar cell systems with passive and active cooling

    NASA Astrophysics Data System (ADS)

    Blumenberg, J.

    1983-10-01

    Design considerations for concentrator solar cell arrays for space applications are reviewed, noting the restrictions on total mass that govern system selections. Consideration is given to systems with parabolic mirrors and Si and GaAs solar cells. Passive and active cooling systems for the arrays are discussed, as is the addition of a heat engine with a turbogenerator to utilize part of the waste heat of the cooling cycle. Attention is given to systems orbiting at 0.5, 1, and 3.5 AU from the sun. Flat panels are found to be more suitable for missions near the sun for Si solar cells, while GaAs cells with concentration are preferred to flat panel systems at all distances from the sun. Nuclear turboelectric systems are better than concentrator Si arrays at large distances from the sun, in terms of specific masses of the systems. The addition of a system to use waste heat is judged unfavorable from specific mass factors.

  6. Sugar compositions, α-glucosidase inhibitory and amylase inhibitory activities of polysaccharides from leaves and flowers of Camellia sinensis obtained by different extraction methods.

    PubMed

    Wang, Yuanfeng; Yang, Zhiwei; Wei, Xinlin

    2010-11-01

    The sugar compositions, α-glucosidase inhibitory and α-amylase inhibitory activities of polysaccharides from leaves and flowers of green tea (Camellia sinensis) obtained by hot water extraction (HWE), boiled water extraction (BWE) and enzymatic extraction (EE) were investigated. The yields, sugar contents and monosaccharide compositions of tea leaves polysaccharides (TLPS) and tea flower polysaccharides (TFPS) were all significantly affected by extraction methods. The contents of acidic polysaccharides (APS) extracted by BWE and EE were both much more than those by HWE. The yields of TLPS and TFPS were determined as EE>BWE>HWE. Enzyme and higher temperature could improve the contents of APS and yields of TLPS and TFPS. TLPS and TFPS were all mainly composed of Rha, Ara, Gal, Glu and GalA, very little molar contents of GluA, Xyl and Man. It seemed that enzyme extraction could be more conducive to increase the content of Ara, Gal and GaLA. The molecular weights of TFPS were larger than those of TLPS. The molecular weights of polysaccharides obtained by EE decreased. Proteins in tea leaves and tea flowers might be decomposed by EE by observing UV peaks and IR absorption. peaks. The α-glucosidase inhibitory and amylase inhibitory activities of TLPS and TFPS obtained by EE were lower than those by water extracted method. The inhibitory percentages of TLPS and TFPS against α-amylase were all lower than α-glucosidase for different extractions.

  7. In vitro and in vivo evaluation of the antioxidant and prooxidant activity of phenolic compounds obtained from grape (Vitis vinifera) pomace.

    PubMed

    Cotoras, Milena; Vivanco, Herman; Melo, Ricardo; Aguirre, María; Silva, Evelyn; Mendoza, Leonora

    2014-01-01

    The antioxidant and/or prooxidant ability of extracts obtained from wine waste were analyzed using in vitro and in vivo assays. Cyclic voltammetry was used as the in vitro assay to determine the antioxidant and/or prooxidant properties and, the in vivo effect on mycelial growth of the fungus Botrytis cinerea was evaluated. In addition, the prooxidant activity was evaluated by intracellular oxidation of compound 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) in B. cinerea. The extracts used in this study were obtained from grape pomace of Cabernet Sauvignon, Carménère and Syrah varieties from the Misiones de Rengo Vineyard by simple extraction, using methanol/HCl 1% (v/v), ethanol 70% (v/v), or Soxhlet extraction. According to the results obtained, gallic acid was the most represented phenolic compound independent of grape variety and extraction method. In addition, vanillic acid; protocatechuic acid, syringic acid, quercetin and kaempferol were found in the extracts. From this study it was possible concluded that, depending of the method of extraction of the grape residues and the grape variety (Cabernet Sauvignon, Carménère and Syrah), the extracts showed antioxidant and/or prooxidant activity. However, no correlation can be established between the anodic oxidation potentials of the extracts and their effect on the fungus B. cinerea. PMID:25521116

  8. In vitro and in vivo evaluation of the antioxidant and prooxidant activity of phenolic compounds obtained from grape (Vitis vinifera) pomace.

    PubMed

    Cotoras, Milena; Vivanco, Herman; Melo, Ricardo; Aguirre, María; Silva, Evelyn; Mendoza, Leonora

    2014-12-16

    The antioxidant and/or prooxidant ability of extracts obtained from wine waste were analyzed using in vitro and in vivo assays. Cyclic voltammetry was used as the in vitro assay to determine the antioxidant and/or prooxidant properties and, the in vivo effect on mycelial growth of the fungus Botrytis cinerea was evaluated. In addition, the prooxidant activity was evaluated by intracellular oxidation of compound 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) in B. cinerea. The extracts used in this study were obtained from grape pomace of Cabernet Sauvignon, Carménère and Syrah varieties from the Misiones de Rengo Vineyard by simple extraction, using methanol/HCl 1% (v/v), ethanol 70% (v/v), or Soxhlet extraction. According to the results obtained, gallic acid was the most represented phenolic compound independent of grape variety and extraction method. In addition, vanillic acid; protocatechuic acid, syringic acid, quercetin and kaempferol were found in the extracts. From this study it was possible concluded that, depending of the method of extraction of the grape residues and the grape variety (Cabernet Sauvignon, Carménère and Syrah), the extracts showed antioxidant and/or prooxidant activity. However, no correlation can be established between the anodic oxidation potentials of the extracts and their effect on the fungus B. cinerea.

  9. The effects of perioperatively administered crystalloids and colloids on concentrations of molecular markers of activated coagulation and fibrinolysis.

    PubMed

    Fries, Dietmar; Streif, Werner; Margreiter, Josef; Klingler, Anton; Kühbacher, Gabriele; Schobersberger, Wolfgang; Wirleitner, Barbara; Innerhofer, Petra

    2004-04-01

    To explore whether intravenous administration of routinely used crystalloid or colloid solutions differently affects the coagulation system, we investigated orthopaedic patients. Since crystalloid solutions might cause hypercoagulability, we here present our results on molecular markers of coagulation and fibrinolysis. Patients undergoing knee replacement surgery randomly received isovolemic amounts of lactated Ringer's solution, 6% hydroxyethyl starch 200/0.5 or 4% modified gelatine. Arterial blood samples for determination of specific molecular markers of activated coagulation (thrombin/antithrombin complex, D-dimer, prothrombin fragment F1 + 2), fibrinolysis (plasmin/alpha 2-antiplasmin complex, tissue plasminogen activator, plasminogen activator inhibitor-1), and concentrations of coagulation factor XIII were obtained at baseline, before tourniquet release, at the end of surgery and 2 h after operation. During the observation period, thrombin/antithrombin complex increased from 4.8 to 54.7 microg/l, D-dimer increased from 0.3 to 6.0 mg/ml, prothrombin fragment F1 + 2 increased from 1.7 to 5.9 nmol/l, tissue plasminogen activator decreased from 7.3 to 6.7 ng/ml, plasminogen activator inhibitor-1 increased from 68.4 to 71.0 ng/ml, plasmin/alpha 2-antiplasmin complex increased from 281.5 to 884 microg/l and factor XIII decreased from 89.0 to 58.5%. All parameters changed significantly but without any detectable difference in the response profile between the groups receiving different intravenous fluids. During knee replacement surgery a pronounced activation of the coagulation/fibrinolytic system was observed, regardless of whether patients received crystalloid or colloid fluids. Thus, these results cannot confirm the hypothesis that crystalloid fluids per se cause hypercoagulability in vivo.

  10. Detection of enteric viruses in activated sludge by feasible concentration methods

    PubMed Central

    Prado, Tatiana; Gaspar, Ana Maria Coimbra; Miagostovich, Marize Pereira

    2014-01-01

    Human enteric viruses are responsible to cause several diseases, including gastroenteritis and hepatitis, and can be present in high amounts in sewage sludge. This study compared virus recovery efficiency of two feasible concentration methods used for detecting human adenovirus (HAdV), rotavirus species A (RV-A), norovirus genogroup II (NoV GII) and hepatitis A virus (HAV) in sewage sludge from an activated sludge process. Twelve sewage sludge samples were collected bi-monthly from January to July, 2011. Ultracentrifugation was compared with a simplified protocol based on beef extract elution for recovering enteric viruses. Viruses were quantified by quantitative real-time PCR assays and virus recovery efficiency and limits of detection were determined. Methods showed mean recovery rates lower than 7.5%, presenting critical limits of detection (higher than 102 – 103 genome copies - GC L−1 for all viruses analyzed). Nevertheless, HAdV were detected in 90% of the analyzed sewage sludge samples (range: 1.8 × 104 to 1.1 × 105 GC L−1), followed by RV-A and NoV (both in 50%) and HAV (8%). Results suggesting that activated sludge is contaminated with high viral loads and HAdV are widely disseminated in these samples. The low virus recovery rates achieved, especially for HAV, indicate that other feasible concentration methods could be developed to improve virus recovery efficiency in these environmental matrices. PMID:24948954

  11. RNA Remodeling Activity of DEAD Box Proteins Tuned by Protein Concentration, RNA Length, and ATP.

    PubMed

    Kim, Younghoon; Myong, Sua

    2016-09-01

    DEAD box RNA helicases play central roles in RNP biogenesis. We reported earlier that LAF-1, a DEAD box RNA helicase in C. elegans, dynamically interacts with RNA and that the interaction likely contributes to the fluidity of RNP droplets. Here we investigate the molecular basis of the interaction of RNA with LAF-1 and its human homolog, DDX3X. We show that both LAF-1 and DDX3X, at low concentrations, are monomers that induce tight compaction of single-stranded RNA. At high concentrations, the proteins are multimeric and dynamically interact with RNA in an RNA length-dependent manner. The dynamic LAF-1-RNA interaction stimulates RNA annealing activity. ATP adversely affects the RNA remodeling ability of LAF-1 by suppressing the affinity, dynamics, and annealing activity of LAF-1, suggesting that ATP may promote disassembly of the RNP complex. Based on our results, we postulate a plausible molecular mechanism underlying the dynamic equilibrium of the LAF-1 RNP complex. PMID:27546789

  12. High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

    PubMed

    Nøst, Therese H; Halse, Anne K; Randall, Scott; Borgen, Anders R; Schlabach, Martin; Paul, Alak; Rahman, Atiqur; Breivik, Knut

    2015-10-01

    The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites. PMID:26351879

  13. High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

    PubMed

    Nøst, Therese H; Halse, Anne K; Randall, Scott; Borgen, Anders R; Schlabach, Martin; Paul, Alak; Rahman, Atiqur; Breivik, Knut

    2015-10-01

    The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites.

  14. Radiological hazards of Narghile (hookah, shisha, goza) smoking: activity concentrations and dose assessment.

    PubMed

    Khater, Ashraf E M; Abd El-Aziz, Nawal S; Al-Sewaidan, Hamed A; Chaouachi, Kamal

    2008-12-01

    Narghile (hookah, shisha, goza, "water-pipe") smoking has become fashionable worldwide. Its tobacco pastes, known as moassel and jurak, are not standardized and generally contain about 30-50% (sometimes more) tobacco, molasses/juice of sugarcane, various spices and dried fruits (particularly in jurak) and, in the case of moassel, glycerol and flavoring essences. Tobacco contains minute amounts of radiotoxic elements such as (210)Pb, (210)Po and uranium, which are inhaled via smoking. Only very few data have been published on the concentrations of natural radionuclides in narghile tobacco mixtures. Consequently, the aim of this study was to draw first conclusions on the potential hazards of radioactivity in moassel tobacco in relation to narghile smoking. The results indicate the existence of a wide range in the radioactivity contents where the average (range) activity concentrations of (238)U, (234)Th (226)Ra, (210)Pb, (210)Po, (232)Th and (40)K, in Bq/kg dry weight were 55 (19-93), 11 (3-23), 3 (1.2-8), 14 (3-29), 13 (7-32), 7 (4-10) and 719 (437-1044)Bq/kg dry weight, respectively. The average concentrations of natural radionuclides in moassel tobacco pastes are comparable to their concentration in Greek cigarettes and tobacco leaves, and lower than that of Brazilian tobacco leaves. The distribution pattern of these radionuclides after smoking, between smoke, ash and filter, is unknown, except for (210)Po during cigarette smoking and from one existing study during moassel smoking. Radiological dose assessment due to intake of natural radionuclides was calculated and the possible radio-toxicity of the measured radionuclides is briefly discussed. PMID:18768240

  15. Comparative hepatic cytochrome P450 activities and contaminant concentrations in caged carp and juvenile ducks

    SciTech Connect

    O`Keefe, P.; Gierthy, J.; Connor, S.; Bush, B.; Hong, C.S.; Wood, L.; Clayton, W.; Storm, R.

    1995-12-31

    Juvenile carp (Cyprinius carpio) weighing approx. 60 g were placed in cages located on the surface of sediments near an aluminum plant and an automobile parts plant in the Massena area of the St. Lawrence River. Fish were removed at weekly intervals over a 35 day exposure period and composited samples of liver tissue, cranial lipid, and fillet tissue were prepared for analysis of polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs). Liver tissue was also stored at {minus}80 C for determination of microsomal Cytochrome P450 activity using the aryl hydrocarbon hydroxylase (AHH) assay. A control exposure was carried out upstream at an uncontaminated site. Juvenile pre-flight ducks (mallards, gadwalls, wood ducks and common mergansers) were collected in the contaminated areas on the St. Lawrence and on the Hudson River two to three months after hatching. Control pre-flight mallards, wood ducks and common mergansers were collected from remote lakes in the Addirondack State Park. Samples of subcutaneous fat and liver tissue were removed for analysis as described above for the carp. There was a three fold increase in AHH activity in the carp liver tissue at the end of the 35 day exposure period and there was a similar increase it activity for the mallards, common mergansers and wood ducks compared to controls. For each species the enzyme activity increases will be compared to the contaminant concentrations.

  16. Monitoring the concentrations of nonsteroidal anti-inflammatory drugs and cyclooxygenase-inhibiting activities in the surface waters of the Tone Canal and Edo River Basin.

    PubMed

    Nishi, Iwaki; Kawakami, Tsuyoshi; Onodera, Sukeo

    2015-01-01

    Environmental pollution by pharmaceuticals has become a major problem in many countries worldwide. However, little is known about the concentrations of pharmaceuticals in water sources in Japan. The objective of this study was to clarify variations in the concentrations of seven nonsteroidal anti-inflammatory drugs (NSAIDs) and in cyclooxygenase(COX)-inhibiting activities in river water and domestic wastewater collected from the Tone Canal and the Edo River Basin in Japan. Total NSAID concentrations were higher in the Tone Canal than in the Edo River, and the highest concentration was observed at the domestic wastewater inflow point located in the Tone Canal (concentration averages of salicylic acid, ibuprofen, felbinac, naproxen, mefenamic acid, diclofenac, and ketoprofen in wastewater samples were 55.3, 162.9, 39.7, 11.8, 30.8, 259.7, and 48.3 ng L(-1), respectively). Gas chromatography-tandem mass spectrometry showed that wastewater samples collected during cooler seasons contained higher levels of COX-inhibiting activity. COX-inhibiting activities were highly correlated with NSAID concentrations (particularly for ketoprofen and diclofenac); however, other COX inhibitors, such as NSAIDs that were not examined in this study and/or other chemicals with COX-inhibiting activity, could exist in the water samples because the concentrations of NSAIDs obtained from the water samples did not account for the total COX-inhibiting activities observed. Therefore, COX inhibition assays may be helpful for evaluating the aquatic toxicity of COX inhibitors. In this study, we demonstrated that COX inhibitors in surface water may influence aquatic organisms more than was expected based on NSAID concentrations. Thus, further studies examining other COX inhibitors in the aquatic environment are necessary. PMID:26191985

  17. CuO/ZnO coupled oxide films obtained by the electrodeposition technique and their photocatalytic activity in phenol degradation under solar irradiation.

    PubMed

    Paz, Diego S; Foletto, Edson L; Bertuol, Daniel A; Jahn, Sérgio L; Collazzo, Gabriela C; da Silva, Syllos S; Chiavone-Filho, Osvaldo; do Nascimento, Claudio A O

    2013-01-01

    CuO/ZnO coupled oxide films were electrodeposited onto an aluminum substrate and tested as photocatalysts in degradation of phenol molecules in aqueous solution under sunlight. The obtained films were characterized by X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results showed that the photocatalytic activity of films was significant, especially to coupled oxide film with a CuO/ZnO ratio equal to 0.697, which presented about 70% degradation of the aromatic molecules and 42% of total organic carbon (TOC) removal at 300 min under solar irradiation. Therefore, this work highlights the potential application of CuO/ZnO coupled oxide films obtained by electrodeposition onto aluminum substrate in the field of photocatalysis.

  18. Meditation-related activations are modulated by the practices needed to obtain it and by the expertise: an ALE meta-analysis study.

    PubMed

    Tomasino, Barbara; Fregona, Sara; Skrap, Miran; Fabbro, Franco

    2012-01-01

    The brain network governing meditation has been studied using a variety of meditation practices and techniques practices eliciting different cognitive processes (e.g., silence, attention to own body, sense of joy, mantras, etc.). It is very possible that different practices of meditation are subserved by largely, if not entirely, disparate brain networks. This assumption was tested by conducting an activation likelihood estimation (ALE) meta-analysis of meditation neuroimaging studies, which assessed 150 activation foci from 24 experiments. Different ALE meta-analyses were carried out. One involved the subsets of studies involving meditation induced through exercising focused attention (FA). The network included clusters bilaterally in the medial gyrus, the left superior parietal lobe, the left insula and the right supramarginal gyrus (SMG). A second analysis addressed the studies involving meditation states induced by chanting or by repetition of words or phrases, known as "mantra." This type of practice elicited a cluster of activity in the right SMG, the SMA bilaterally and the left postcentral gyrus. Furthermore, the last analyses addressed the effect of meditation experience (i.e., short- vs. long-term meditators). We found that frontal activation was present for short-term, as compared with long-term experience meditators, confirming that experts are better enabled to sustain attentional focus, rather recruiting the right SMG and concentrating on aspects involving disembodiment. PMID:23316154

  19. Meditation-related activations are modulated by the practices needed to obtain it and by the expertise: an ALE meta-analysis study

    PubMed Central

    Tomasino, Barbara; Fregona, Sara; Skrap, Miran; Fabbro, Franco

    2013-01-01

    The brain network governing meditation has been studied using a variety of meditation practices and techniques practices eliciting different cognitive processes (e.g., silence, attention to own body, sense of joy, mantras, etc.). It is very possible that different practices of meditation are subserved by largely, if not entirely, disparate brain networks. This assumption was tested by conducting an activation likelihood estimation (ALE) meta-analysis of meditation neuroimaging studies, which assessed 150 activation foci from 24 experiments. Different ALE meta-analyses were carried out. One involved the subsets of studies involving meditation induced through exercising focused attention (FA). The network included clusters bilaterally in the medial gyrus, the left superior parietal lobe, the left insula and the right supramarginal gyrus (SMG). A second analysis addressed the studies involving meditation states induced by chanting or by repetition of words or phrases, known as “mantra.” This type of practice elicited a cluster of activity in the right SMG, the SMA bilaterally and the left postcentral gyrus. Furthermore, the last analyses addressed the effect of meditation experience (i.e., short- vs. long-term meditators). We found that frontal activation was present for short-term, as compared with long-term experience meditators, confirming that experts are better enabled to sustain attentional focus, rather recruiting the right SMG and concentrating on aspects involving disembodiment. PMID:23316154

  20. Meditation-related activations are modulated by the practices needed to obtain it and by the expertise: an ALE meta-analysis study.

    PubMed

    Tomasino, Barbara; Fregona, Sara; Skrap, Miran; Fabbro, Franco

    2012-01-01

    The brain network governing meditation has been studied using a variety of meditation practices and techniques practices eliciting different cognitive processes (e.g., silence, attention to own body, sense of joy, mantras, etc.). It is very possible that different practices of meditation are subserved by largely, if not entirely, disparate brain networks. This assumption was tested by conducting an activation likelihood estimation (ALE) meta-analysis of meditation neuroimaging studies, which assessed 150 activation foci from 24 experiments. Different ALE meta-analyses were carried out. One involved the subsets of studies involving meditation induced through exercising focused attention (FA). The network included clusters bilaterally in the medial gyrus, the left superior parietal lobe, the left insula and the right supramarginal gyrus (SMG). A second analysis addressed the studies involving meditation states induced by chanting or by repetition of words or phrases, known as "mantra." This type of practice elicited a cluster of activity in the right SMG, the SMA bilaterally and the left postcentral gyrus. Furthermore, the last analyses addressed the effect of meditation experience (i.e., short- vs. long-term meditators). We found that frontal activation was present for short-term, as compared with long-term experience meditators, confirming that experts are better enabled to sustain attentional focus, rather recruiting the right SMG and concentrating on aspects involving disembodiment.

  1. Concentrations of haptoglobin in bovine plasma determined by ELISA or a colorimetric method based on peroxidase activity.

    PubMed

    Cooke, R F; Arthington, J D

    2013-06-01

    The objective was to compare different procedures for determination of haptoglobin in bovine plasma. Nine Angus steers were vaccinated against Mannheimia haemolytica to stimulate an acute-phase response. Blood samples were collected immediately prior to vaccination (day 0), and on days 1, 3, 5, 7 and 10. Plasma samples were frozen in duplicates at -80 °C. One set of the duplicates was analysed for haptoglobin concentrations using a commercial ELISA kit. A day effect was detected (p < 0.01) because haptoglobin peaked on day 3 and returned to baseline on day 7 relative to vaccination. The second duplicate was analysed using a procedure that measures haptoglobin-haemoglobin complexing by estimating differences in peroxidase activity (CPPA) with results expressed as optical density. Further, based on the ELISA results, the plasma sample with the greatest haptoglobin concentration was also serially diluted into a plasma sample with negligible haptoglobin concentration from the same steer (1:1 through 1:1024 dilution). These dilutions were used within the CPPA method to generate a standard curve and estimate plasma haptoglobin concentrations (CPPA + STD). A linear standard curve was generated (r(2)  = 0.99). A day effect similar to the ELISA method was detected for the CPPA and CPPA + STD methods (p < 0.01). Results obtained from CPPA and ELISA methods were positively correlated (r = 0.97; p < 0.01). The values generated by the CPPA + STD procedure were similar (p = 0.38) compared to the values generated by the ELISA method. In conclusion, assessing concentrations of haptoglobin in bovine plasma using the CPPA and CPPA + STD methods generate highly correlated or similar results, respectively, compared to ELISA. Therefore, the CPPA + STD and CPPA methods can be used as a less expensive alternative to ELISA to determine concentrations or monitor changes in plasma haptoglobin in bovine samples.

  2. Ceratonia siliqua L. hydroethanolic extract obtained by ultrasonication: antioxidant activity, phenolic compounds profile and effects in yogurts functionalized with their free and microencapsulated forms.

    PubMed

    Rached, Irada; Barros, Lillian; Fernandes, Isabel P; Santos-Buelga, Celestino; Rodrigues, Alírio E; Ferchichi, Ali; Barreiro, Maria Filomena; Ferreira, Isabel C F R

    2016-03-01

    Bioactive extracts were obtained from powdered carob pulp through an ultrasound extraction process and then evaluated in terms of antioxidant activity. Ten minutes of ultrasonication at 375 Hz were the optimal conditions leading to an extract with the highest antioxidant effects. After its chemical characterization, which revealed the preponderance of gallotannins, the extract (free and microencapsulated) was incorporated in yogurts. The microspheres were prepared using an extract/sodium alginate ratio of 100/400 (mg mg(-1)) selected after testing different ratios. The yogurts with the free extract exhibited higher antioxidant activity than the samples added with the encapsulated extracts, showing the preserving role of alginate as a coating material. None of the forms significantly altered the yogurt's nutritional value. This study confirmed the efficiency of microencapsulation to stabilize functional ingredients in food matrices maintaining almost the structural integrity of polyphenols extracted from carob pulp and furthermore improving the antioxidant potency of the final product. PMID:26887343

  3. Response of soil microbial activity and biodiversity in soils polluted with different concentrations of cypermethrin insecticide.

    PubMed

    Tejada, Manuel; García, Carlos; Hernández, Teresa; Gómez, Isidoro

    2015-07-01

    We performed a laboratory study into the effect of cypermethrin insecticide applied to different concentrations on biological properties in two soils [Typic Xerofluvent (soil A) and Xerollic Calciorthid (soil B)]. Two kg of each soil were polluted with cypermethrin at a rate of 60, 300, 600, and 1,200 g ha(-1) (C1, C2, C3, and C4 treatments). A nonpolluted soil was used as a control (C0 treatment). For all treatments and each experimental soil, soil dehydrogenase, urease, β-glucosidase, phosphatase, and arylsulphatase activities and soil microbial community were analysed by phospholipid fatty acids, which were measured at six incubation times (3, 7, 15, 30, 60, and 90 days). The behavior of the enzymatic activities and microbial population were dependent on the dose of insecticide applied to the soil. Compared with the C0 treatment, in soil A, the maximum inhibition of the enzymatic activities was at 15, 30, 45, and 90 days for the C1, C2, C3, and C4 treatments, respectively. However, in soil B, the maximum inhibition occurred at 7, 15, 30, and 45 days for the C1, C2, C3, and C4 treatments, respectively. These results suggest that the cypermethrin insecticide caused a negative effect on soil enzymatic activities and microbial diversity. This negative impact was greater when a greater dose of insecticide was used; this impact was also greater in soil with lower organic matter content. For both soils, and from these respective days onward, the enzymatic activities and microbial populations progressively increased by the end of the experimental period. This is possibly due to the fact that the insecticide or its breakdown products and killed microbial cells, subsequently killed by the insecticide, are being used as a source of energy or as a carbon source for the surviving microorganisms for cell proliferation.

  4. Antioxidative enzymes activity and malondialdehyde concentration during mitoxantrone therapy in multiple sclerosis patients.

    PubMed

    Adamczyk-Sowa, M; Sowa, P; Pierzchala, K; Polaniak, R; Labuz-Roszak, B

    2012-12-01

    Mitoxantrone (MX) is approved for the treatment of aggressive relapsing-remitting, secondary-progressive and progressive-relapsing form of multiple sclerosis (MS). The mechanism of its action is multiaxial, however, it is not free from side effects. The causes of the side effects are still unknown and require further investigation. The aim of this study was to investigate the influence of MX therapy on enzymatic parameters of endogenous antioxidative status: manganese and copper/zinc superoxide dismutase (MnSOD, Cu/ZnSOD), catalase (CAT), glutathione peroxidase (GSH-Px) and lipid peroxidation marker--malondialdehyde (MDA) in blood serum and cerebrospinal fluid (CSF) in patients suffering from MS. After the MX therapy serum and the CSF MDA concentrations increased significantly. We reported that MnSOD activities decrease in serum and the CSF, while, surprisingly, the serum Cu/ZnSOD activity increases after the MX therapy. We also noted a marked decrease in CSF CAT and GSH-Px activity after the MX treatment. Our results strongly suggest the influence of MX therapy on oxidation/antioxidation status of serum and the CSF. These findings open up new opportunities for a better understanding of underlying physiopathological events in MS and provide a new insight into MX's mechanisms of action, especially its potent side effects.

  5. Impact of enzyme concentration and residence time on apparent activity recovery in jump dilution analysis.

    PubMed

    Copeland, Robert A; Basavapathruni, Aravind; Moyer, Mikel; Scott, Margaret Porter

    2011-09-15

    Jump dilution analysis is commonly used to evaluate the reversibility of inhibition and to quantify the residence time of the inhibitor-enzyme complex. During hit and lead characterization, one sometimes observes apparently linear progress curves after jump dilution that display activity recoveries that are intermediate between those expected for fully reversible and irreversible inhibition. Computer simulations of progress curves after jump dilution indicate that seemingly linear progress curves can result when dealing with tight-binding inhibitors if substoichiometric concentrations of inhibitor are preincubated with enzyme. In this situation, the activity recovered is comparable to that expected for instantaneously reversible inhibitors. In addition, simulations demonstrate that intermediate values of activity recovery may be observed for compounds with modestly slow dissociation rates (i.e., residence times >0min but ≤20min) when the attending curvature of the data is not accounted for. The observation of intermediate values of recovery can, thus, serve as an indication of either modest residence time or a contaminating inactivator within an inhibitor sample, in either case prompting greater scrutiny of the test compound.

  6. Metabolic activity of sperm cells: correlation with sperm cell concentration, viability and motility in the rabbit.

    PubMed

    Sabés-Alsina, Maria; Planell, Núria; Gil, Sílvia; Tallo-Parra, Oriol; Maya-Soriano, Maria José; Taberner, Ester; Piles, Miriam; Sabés, Manel; Lopez-Bejar, Manel

    2016-10-01

    The resazurin reduction test (RRT) is a useful technique to assess the metabolic rate of sperm cells. RRT depends on the ability of metabolically active cells to reduce the non-fluorescent dye resazurin to the fluorescent resorufin. The aim of this study was to develop a vital fluorometric method to evaluate metabolic activity of rabbit sperm cells. Twenty-five rabbit males were included in the study. Viability and morphology, motility and metabolic activity were evaluated using an eosin-nigrosin staining, a computer-assisted semen analysis (CASA) and the RRT, respectively. Spearman rank correlation analysis was used to determine the correlation between RRT and semen parameters. After evaluation, a concentration of 10 × 106 sperm cells/ml was selected for further experiments with RRT. No significant correlation was found between the RRT results and the motility parameters. However, after RRT a significant positive correlation between relative fluorescence units and the percentage of alive spermatozoa (r = 0.62; P = 0.001) and a negative one with the percentage of sperm cells with acrosomic abnormalities (r = -0.45; P < 0.05) were detected. The vital assessment of metabolic rate of sperm cells by RRT could provide more information about semen quality than other routine semen analysis, correlating with sperm viability and acrosome status information.

  7. Activity concentrations of environmental samples collected in Fukushima Prefecture immediately after the Fukushima nuclear accident

    PubMed Central

    Hosoda, Masahiro; Tokonami, Shinji; Tazoe, Hirofumi; Sorimachi, Atsuyuki; Monzen, Satoru; Osanai, Minoru; Akata, Naofumi; Kakiuchi, Hideki; Omori, Yasutaka; Ishikawa, Tetsuo; Sahoo, Sarata K.; Kovács, Tibor; Yamada, Masatoshi; Nakata, Akifumi; Yoshida, Mitsuaki; Yoshino, Hironori; Mariya, Yasushi; Kashiwakura, Ikuo

    2013-01-01

    Radionuclide concentrations in environmental samples such as surface soils, plants and water were evaluated by high purity germanium detector measurements. The contribution rate of short half-life radionuclides such as 132I to the exposure dose to residents was discussed from the measured values. The highest values of the 131I/137Cs activity ratio ranged from 49 to 70 in the environmental samples collected at Iwaki City which is located to the south of the F1-NPS. On the other hand, the 132I/131I activity ratio in the same environmental samples had the lowest values, ranging from 0.01 to 0.02. By assuming that the 132I/131I activity ratio in the atmosphere was equal to the ratio in the environmental samples, the percent contribution to the thyroid equivalent dose by 132I was estimated to be less than 2%. Moreover, the contribution to the thyroid exposure by 132I might be negligible if 132I contamination was restricted to Iwaki City. PMID:23887080

  8. Effect of Supplementation with Wheat Bran Aqueous Extracts Obtained by Ultrasound-Assisted Technologies on the Sensory Properties and the Antioxidant Activity of Dry Pasta.

    PubMed

    Pasqualone, Antonella; Delvecchio, Laura Nunzia; Gambacorta, Giuseppe; Laddomada, Barbara; Urso, Valeria; Mazzaglia, Agata; Ruisi, Paolo; Di Miceli, Giuseppe

    2015-10-01

    Phenolic compounds have antioxidant properties and activate endogenous detoxification defense systems able to scavenge the reactive species of oxygen. The external layers of wheat caryopsis, largely constituting by-products of the milling industry such as bran and various middlings, contain relevant amounts of phenolic compounds. The aim of the research has been to evaluate the effect of supplementation with wheat bran aqueous extracts, obtained by ultrasound-assisted technologies, on the sensory properties and antioxidant activity of dry pasta. The HPLC-DAD characterization of the extract evidenced the presence of ferulic and p-coumaric acids. The supplemented pasta showed significantly higher antioxidant activity and phenolic content than the control, coupled to good overall sensory judgment. In addition, two different pasta drying diagrams were adopted, and the comparison of the corresponding end-products allowed it to be pointed out that the processing technology has to be carefully set up to prevent possible detrimental effects on the antioxidant activity. The proposed utilization of bran might add value to a milling by-product that, otherwise, is mostly employed in animal feeding.

  9. Effect of Supplementation with Wheat Bran Aqueous Extracts Obtained by Ultrasound-Assisted Technologies on the Sensory Properties and the Antioxidant Activity of Dry Pasta.

    PubMed

    Pasqualone, Antonella; Delvecchio, Laura Nunzia; Gambacorta, Giuseppe; Laddomada, Barbara; Urso, Valeria; Mazzaglia, Agata; Ruisi, Paolo; Di Miceli, Giuseppe

    2015-10-01

    Phenolic compounds have antioxidant properties and activate endogenous detoxification defense systems able to scavenge the reactive species of oxygen. The external layers of wheat caryopsis, largely constituting by-products of the milling industry such as bran and various middlings, contain relevant amounts of phenolic compounds. The aim of the research has been to evaluate the effect of supplementation with wheat bran aqueous extracts, obtained by ultrasound-assisted technologies, on the sensory properties and antioxidant activity of dry pasta. The HPLC-DAD characterization of the extract evidenced the presence of ferulic and p-coumaric acids. The supplemented pasta showed significantly higher antioxidant activity and phenolic content than the control, coupled to good overall sensory judgment. In addition, two different pasta drying diagrams were adopted, and the comparison of the corresponding end-products allowed it to be pointed out that the processing technology has to be carefully set up to prevent possible detrimental effects on the antioxidant activity. The proposed utilization of bran might add value to a milling by-product that, otherwise, is mostly employed in animal feeding. PMID:26669115

  10. Triglyceride concentration and waist circumference influence alcohol-related plasminogen activator inhibitor-1 activity increase in black South Africans.

    PubMed

    Pieters, Marlien; de Lange, Zelda; Hoekstra, Tiny; Ellis, Suria M; Kruger, Annamarie

    2010-12-01

    We investigated the association between alcohol consumption and plasminogen activator inhibitor-1 activity (PAI-1act) and fibrinogen concentration in a black South African population presenting with lower PAI-1act and higher fibrinogen than what is typically observed in white populations. We, furthermore, wanted to investigate the effect of urbanization, sex, central obesity, increased triglycerides, 4G/5G polymorphism (PAI-1 only) and BMI on the association of alcohol with PAI-1act and fibrinogen. Data from 2010 apparently healthy, randomly collected black South African volunteers from the Prospective Urban and Rural Epidemiological (PURE) study were cross-sectionally analyzed. Alcohol consumption was recorded using quantitative food frequency questionnaires and fasting blood samples were collected for biochemical analysis including PAI-1act and fibrinogen. Heavy alcohol consumption is associated with significantly increased PAI-1act, in the total population as well as in the women separately, and tended to be so in men. This alcohol-related PAI-1act increase was observed in volunteers with increased triglycerides and central obesity but not in volunteers with normal levels and waist circumference. Urbanization, the 4G/5G polymorphism and BMI did not affect the association of alcohol with PAI-1act. Moderate alcohol consumption is associated with decreased fibrinogen concentration. Sex and level of urbanization did not affect the association of alcohol with fibrinogen. Fibrinogen decreased in normal and overweight volunteers but not in obese and centrally obese volunteers following moderate alcohol consumption. Triglyceride levels and waist circumference influence alcohol-related PAI-1act increase potentially through modulating adipocyte and triglyceride-induced PAI-1 production. Obesity prevented alcohol-related fibrinogen decrease possibly by counteracting the anti-inflammatory effect of moderate alcohol consumption.

  11. Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain.

    PubMed

    Takahashi, Hideyuki; Terada, Kazunori; Morita, Tomoyo; Suzuki, Shinsuke; Haji, Tomoki; Kozima, Hideki; Yoshikawa, Masahiro; Matsumoto, Yoshio; Omori, Takashi; Asada, Minoru; Naito, Eiichi

    2014-09-01

    Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior. We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires. We found that the participants perceived opponents in two mental dimensions: one represented "mind-holderness" in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented "mind-readerness" in which participants characterized opponents as intelligent. Interestingly, this "mind-readerness" dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole. These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain

  12. Methanogenic activity inhibition by increasing the linear alkylbenzene sulfonate (LAS) concentration.

    PubMed

    Souza, Luiza F C; Florencio, Lourdinha; Gavazza, Savia; Kato, Mario T

    2016-07-01

    The effect of the initial concentration of linear alkylbenzene sulfonate (LAS) on specific methanogenic activity (SMA) was investigated in this work. Six anaerobic flasks reactors with 1 L of total volume were inoculated with anaerobic sludge (2 g VSS L(-1)). The reactors were assayed for 42 days, and fed with volatile fatty acids, nutrients, and LAS. The initial LAS concentrations were 0, 10, 30, 50, 75, and 100 mg L(-1) for the treatment flasks T1 (control), T2, T3, T4, T5, and T6, respectively. When compared with T1, T2 exhibited a 30% reduction in maximum SMA and total methane production (TMP). In treatment T3 through T6, the reductions were 44-97% (T3-T6) for SMA, and 30-90% (T3-T6) for TMP. Total LAS removal increased following the increase in the initial LAS concentration (from 36% at T1 to 76% at T6), primarily due to the high degree of sludge adsorption. LAS biodegradation also occurred (32% in all treatments), although this was most likely associated with the formation of non-methane intermediates. Greater removal by adsorption was observed in long-chain homologues, when compared to short-chain homologues (C13 > C10), whereas the opposite occurred for biodegradation (C10 > C13). The C13 homologue was adsorbed to a great extent (in mass) in T4, T5 and T6, and may also have inhibited methane formation in these treatments. PMID:27088975

  13. Layered Double Hydroxide Nanoclusters: Aqueous, Concentrated, Stable, and Catalytically Active Colloids toward Green Chemistry.

    PubMed

    Tokudome, Yasuaki; Morimoto, Tsuyoshi; Tarutani, Naoki; Vaz, Pedro D; Nunes, Carla D; Prevot, Vanessa; Stenning, Gavin B G; Takahashi, Masahide

    2016-05-24

    Increasing attention has been dedicated to the development of nanomaterials rendering green and sustainable processes, which occur in benign aqueous reaction media. Herein, we demonstrate the synthesis of another family of green nanomaterials, layered double hydroxide (LDH) nanoclusters, which are concentrated (98.7 g/L in aqueous solvent), stably dispersed (transparent sol for >2 weeks), and catalytically active colloids of nano LDHs (isotropic shape with the size of 7.8 nm as determined by small-angle X-ray scattering). LDH nanoclusters are available as colloidal building blocks to give access to meso- and macroporous LDH materials. Proof-of-concept applications revealed that the LDH nanocluster works as a solid basic catalyst and is separable from solvents of catalytic reactions, confirming the nature of nanocatalysts. The present work closely investigates the unique physical and chemical features of this colloid, the formation mechanism, and the ability to act as basic nanocatalysts in benign aqueous reaction systems. PMID:27124717

  14. Concentration Effects of Polymer Electrolyte Membrane Degradation Products on Oxygen Reduction Activity for Three Platinum Catalysts

    DOE PAGES

    Christ, J. M.; Neyerlin, K. C.; Richards, R.; Dinh, H. N.

    2014-10-04

    A rotating disk electrode (RDE) along with cyclic voltammetry (CV) and linear sweep voltammetry (LSV), were used to investigate the impact of two model compounds representing degradation products of Nafion and 3M perfluorinated sulfonic acid membranes on the electrochemical surface area (ECA) and oxygen reduction reaction (ORR) activity of polycrystalline Pt, nano-structured thin film (NSTF) Pt (3M), and Pt/Vulcan carbon (Pt/Vu) (TKK) electrodes. ORR kinetic currents (measured at 0.9 V and transport corrected) were found to decrease linearly with the log of concentration for both model compounds on all Pt surfaces studied. Ultimately, model compound adsorption effects on ECA weremore » more abstruse due to competitive organic anion adsorption on Pt surfaces superimposing with the hydrogen underpotential deposition (HUPD) region.« less

  15. Strontium-90 and caesium-137 activity concentrations in bats in the Chernobyl exclusion zone.

    PubMed

    Gashchak, Sergey; Beresford, Nicholas Anthony; Maksimenko, Andrey; Vlaschenko, Anton S

    2010-11-01

    Bats are a protected species and as such may be an object of protection in radiological assessments of the environment. However, there have previously been only few radioecological studies of species of bats. In this paper, results for >140 measurements of (90)Sr and (137)Cs in 10 species of bats collected within the Chernobyl zone are presented. There was some indication of a decreasing transfer of (90)Sr with increasing deposition, although this was inconsistent across species and explained little of the observed variability. There was no difference between male and female bats in the transfer (expressed as the ratio of whole-body activity concentrations to those in soil) of either radionuclide. There was considerable variability in transfer across all species groups. At two sites where there were sufficient data, Eptesicus serotinus was found to have higher transfer than other species.

  16. Tuning the surface oxygen concentration of {111} surrounded ceria nanocrystals for enhanced photocatalytic activities

    NASA Astrophysics Data System (ADS)

    Younis, Adnan; Chu, Dewei; Kaneti, Yusuf Valentino; Li, Sean

    2015-12-01

    For oxide semiconductors, the morphology, particle size and oxygen vacancies are usually considered as key influential parameters for photocatalytic degradation of organic pollutants/dyes. It is widely accepted that cation doping not only modifies their phase and microstructures but also introduces variations in oxygen vacancy concentration. Herein, we report the fabrication of sub-10 nm sized pure and indium doped CeO2 nanocrystals (NCs) via a facile, green hydrothermal method for the investigation of photocatalytic activities. X-ray diffraction and transmission electron microscopy were employed to examine the crystal phase and morphology of the as-prepared nanocrystals. Raman and X-ray photoelectron spectroscopy techniques were implemented to investigate the presence and variations in oxygen vacancy concentration in un-doped and indium doped CeO2 nanocrystals. The photocatalytic activity results revealed that 10 at% doping is the optimal indium doping level to demonstrate superior dye removal efficiency (~40%) over un-doped and doped CeO2 NCs. Moreover, the 10% In-doped CeO2 nanocrystals expressed excellent cycling stability and superior photocatalytic performance toward other dye pollutants. Finally, on the basis of our findings, a possible photocatalytic mechanism in which indium doping can generate more surface oxygen vacancies in the ceria lattice which delay the electron-hole recombination rates, thus increasing the lifetime of electron-hole separation for enhanced photocatalytic performances was proposed.For oxide semiconductors, the morphology, particle size and oxygen vacancies are usually considered as key influential parameters for photocatalytic degradation of organic pollutants/dyes. It is widely accepted that cation doping not only modifies their phase and microstructures but also introduces variations in oxygen vacancy concentration. Herein, we report the fabrication of sub-10 nm sized pure and indium doped CeO2 nanocrystals (NCs) via a facile

  17. Management practices that concentrate visitor activities: Camping impact management at Isle Royale National Park, USA

    USGS Publications Warehouse

    Marion, J.L.; Farrell, T.A.

    2002-01-01

    This study assessed campsite conditions and the effectiveness of campsite impact management strategies at Isle Royale National Park, USA. Protocols for assessing indicators of vegetation and soil conditions were developed and applied to 156 campsites and 88 shelters within 36 backcountry campgrounds. The average site was 68 m2 and 83% of sites lost vegetation over areas less than 47 m2. Results reveal that management actions to spatially concentrate camping activities and reduce camping disturbance have been highly successful. Comparisons of disturbed area/overnight stay among other protected areas reinforces this assertion. These reductions in area of camping disturbance are attributed to a designated site camping policy, limitation on site numbers, construction of sites in sloping terrain, use of facilities, and an ongoing program of campsite maintenance. Such actions are most appropriate in higher use backcountry and wilderness settings.

  18. Activity concentrations and population dose from radium-226 in food and drinking water in Taiwan.

    PubMed

    Kuo, Y C; Lai, S Y; Huang, C C; Lin, Y M

    1997-09-01

    The purpose of this study was to determine the radioactivity of 226Ra in environmental samples in Taiwan. Fish, pork, rice, flour, chicken, vegetable, milk, fruit, egg and water samples were collected and pretreated by radiochemical procedure to extract the 226Ra, and the activity concentrations of 226Ra were determined using a liquid scintillation counter. The 226Ra content of groundwater was 12.0 mBq l-1. The 226Ra contents of the food ranged from 0.02 Bq kg-1 fresh to 0.17 Bq kg-1 fresh. The annual internal dose from ingestion of 226Ra from food and drinking water per caput was evaluated to be 7.5 microSv.

  19. Layered Double Hydroxide Nanoclusters: Aqueous, Concentrated, Stable, and Catalytically Active Colloids toward Green Chemistry.

    PubMed

    Tokudome, Yasuaki; Morimoto, Tsuyoshi; Tarutani, Naoki; Vaz, Pedro D; Nunes, Carla D; Prevot, Vanessa; Stenning, Gavin B G; Takahashi, Masahide

    2016-05-24

    Increasing attention has been dedicated to the development of nanomaterials rendering green and sustainable processes, which occur in benign aqueous reaction media. Herein, we demonstrate the synthesis of another family of green nanomaterials, layered double hydroxide (LDH) nanoclusters, which are concentrated (98.7 g/L in aqueous solvent), stably dispersed (transparent sol for >2 weeks), and catalytically active colloids of nano LDHs (isotropic shape with the size of 7.8 nm as determined by small-angle X-ray scattering). LDH nanoclusters are available as colloidal building blocks to give access to meso- and macroporous LDH materials. Proof-of-concept applications revealed that the LDH nanocluster works as a solid basic catalyst and is separable from solvents of catalytic reactions, confirming the nature of nanocatalysts. The present work closely investigates the unique physical and chemical features of this colloid, the formation mechanism, and the ability to act as basic nanocatalysts in benign aqueous reaction systems.

  20. Concentration Effects of Polymer Electrolyte Membrane Degradation Products on Oxygen Reduction Activity for Three Platinum Catalysts

    SciTech Connect

    Christ, J. M.; Neyerlin, K. C.; Richards, R.; Dinh, H. N.

    2014-10-04

    A rotating disk electrode (RDE) along with cyclic voltammetry (CV) and linear sweep voltammetry (LSV), were used to investigate the impact of two model compounds representing degradation products of Nafion and 3M perfluorinated sulfonic acid membranes on the electrochemical surface area (ECA) and oxygen reduction reaction (ORR) activity of polycrystalline Pt, nano-structured thin film (NSTF) Pt (3M), and Pt/Vulcan carbon (Pt/Vu) (TKK) electrodes. ORR kinetic currents (measured at 0.9 V and transport corrected) were found to decrease linearly with the log of concentration for both model compounds on all Pt surfaces studied. Ultimately, model compound adsorption effects on ECA were more abstruse due to competitive organic anion adsorption on Pt surfaces superimposing with the hydrogen underpotential deposition (HUPD) region.

  1. 137Cs activity concentration in wild boar meat may still exceed the permitted levels

    NASA Astrophysics Data System (ADS)

    Rachubik, J.

    2012-04-01

    The radiocaesium activity concentration may still remain high in natural products such as game meat, wild mushrooms, and forest berries even more than two decades after the Chernobyl accident. The results of regular control studies of game meat conducted in Poland showed wild boars as the most contaminated game animals. It is well documented that some mushrooms, readily consumed by animals, show high ability to accumulate caesium radioisotopes. Bay bolete, one of the most wide-spread mushroom species in Poland, reveals a unique radiocaesium accumulation feature. Moreover, deer truffle, containing also particularly high levels of radiocaesium, could be another radionu-clide source for wild boars. Furthermore, animals consuming deer truffles could digest contaminated soil components. Among 94 wild boar meat samples analysed in 2008-2009, two exceeded the permitted level. Hence, some precautions should be taken in the population with an elevated intake of wild boar meat. Moreover, since each hunted wild boar is examined for the presence of Trichinella larvae, regular measurements of radiocaesium concentrations in these animals may be advisable for enhancing consumer safety.

  2. [In vitro antifungal susceptibility, in vivo antifungal activity and security from a natural product obtained from sunrise oil (AMO3) against dermatophytes].

    PubMed

    Thomson M, Pamela; Anticevic C, Sonia; Rodríguez B, Héctor; Silva V, Víctor

    2011-12-01

    This work studied safety and antifungal activity of ozonized sunflower oil (AMO3) against dermatophytes. AMO3 was prepared through a new original process that modifies the oil before ozonation by alcoholic catalytic esterification. Susceptibility was studied in 41 dermatophytes by agar diffusion and broth microdilution tests. The experimental model to assess the topical safety of the oil included 60 CF1 mice divided in three groups that were treated with vaseline (control), 1% AMO3 and 50% AMO3 (overdose), respectively. Then, experimental dermatophytosis was induced in CF1 mice. Seventy-five individuals were selected and divided in 5 groups that were treated once a day with placebo, cream with 1%, 2% and 3% AMO3 plus an untreated control group. This new natural product showed antifungal activity against all strains studied. The MIC ranged between was 0,125 and 1%, while minimum fungicidal concentration (MFC) was 2%. The application of vaseline and AMO3 1% and 50% did not produce clinical or histopathological lesions. The mice with dermatophytosis that were treated with 1%, 2% and 3% AMO3 showed 100% clinical cure and 94% average mycological cure, exceeding placebo and control groups (p < 0,05). This product exhibits high antifungal activity and could be a safe alternative for ringworm topical treatment. PMID:22286673

  3. Concentration-dependent activation of dopamine receptors differentially modulates GABA release onto orexin neurons.

    PubMed

    Linehan, Victoria; Trask, Robert B; Briggs, Chantalle; Rowe, Todd M; Hirasawa, Michiru

    2015-08-01

    Dopamine (DA) and orexin neurons play important roles in reward and food intake. There are anatomical and functional connections between these two cell groups: orexin peptides stimulate DA neurons in the ventral tegmental area and DA inhibits orexin neurons in the hypothalamus. However, the cellular mechanisms underlying the action of DA on orexin neurons remain incompletely understood. Therefore, the effect of DA on inhibitory transmission to orexin neurons was investigated in rat brain slices using the whole-cell patch-clamp technique. We found that DA modulated the frequency of spontaneous and miniature IPSCs (mIPSCs) in a concentration-dependent bidirectional manner. Low (1 μM) and high (100 μM) concentrations of DA decreased and increased IPSC frequency, respectively. These effects did not accompany a change in mIPSC amplitude and persisted in the presence of G-protein signaling inhibitor GDPβS in the pipette, suggesting that DA acts presynaptically. The decrease in mIPSC frequency was mediated by D2 receptors whereas the increase required co-activation of D1 and D2 receptors and subsequent activation of phospholipase C. In summary, our results suggest that DA has complex effects on GABAergic transmission to orexin neurons, involving cooperation of multiple receptor subtypes. The direction of dopaminergic influence on orexin neurons is dependent on the level of DA in the hypothalamus. At low levels DA disinhibits orexin neurons whereas at high levels it facilitates GABA release, which may act as negative feedback to curb the excitatory orexinergic output to DA neurons. These mechanisms may have implications for consummatory and motivated behaviours.

  4. Enhanced antibacterial activity of bimetallic gold-silver core-shell nanoparticles at low silver concentration

    NASA Astrophysics Data System (ADS)

    Banerjee, Madhuchanda; Sharma, Shilpa; Chattopadhyay, Arun; Ghosh, Siddhartha Sankar

    2011-12-01

    Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was possibly due to the more active silver atoms in the shell surrounding gold core due to high surface free energy of the surface Ag atoms owing to shell thinness in the bimetallic NP structure.Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was

  5. Effect of Phosphoric Acid Concentration on the Characteristics of Sugarcane Bagasse Activated Carbon

    NASA Astrophysics Data System (ADS)

    Adib, M. R. M.; Suraya, W. M. S. W.; Rafidah, H.; Amirza, A. R. M.; Attahirah, M. H. M. N.; Hani, M. S. N. Q.; Adnan, M. S.

    2016-07-01

    Impregnation method is one of the crucial steps involved in producing activated carbon using chemical activation process. Chemicals employed in this step is effective at decomposing the structure of material and forming micropores that helps in adsorption of contaminants. This paper explains thorough procedures that have been involved in producing sugarcane bagasse activated carbon (SBAC) by using 5%, 10%, 20%, 30% phosphoric acid (H3PO4) during the impregnation step. Concentration of H3PO4 used in the process of producing SBAC was optimized through several tests including bulk density, ash content, iodine adsorption and pore size diameter and the charactesristic of optimum SBAC produced has been compared with commercial activated carbon (CAC). Batch study has been carried out by using the SBAC produced from optimum condition to investigate the performance of SBAC in removal of turbidity and chemical oxygen demand (COD) from textile wastewater. From characteristic study, SBAC with 30% H3PO4 has shown the optimum value of bulk density, ash content, iodine adsorption and pore size diameter of 0.3023 g cm-3, 4.35%, 974.96 mg/g and 0.21-0.41 µm, respectively. These values are comparable to the characteristics of CAC. Experimental result from the batch study has been concluded that the SBAC has a promising potential in removing turbidity and COD of 75.5% and 66.3%, respectively which was a slightly lower than CAC which were able to remove 82.8% of turbidity and 70% of COD. As a conclusion, the SBAC is comparable with CAC in terms of their characteristics and the capability of removing contaminants from textile wastewater. Therefore, it has a commercial value to be used as an alternative of low-cost material in producing CAC.

  6. Effect of biomass concentration on methane oxidation activity using mature compost and graphite granules as substrata.

    PubMed

    Xie, S; O'Dwyer, T; Freguia, S; Pikaar, I; Clarke, W P

    2016-10-01

    Reported methane oxidation activity (MOA) varies widely for common landfill cover materials. Variation is expected due to differences in surface area, the composition of the substratum and culturing conditions. MOA per methanotrophic cell has been calculated in the study of natural systems such as lake sediments to examine the inherent conditions for methanotrophic activity. In this study, biomass normalised MOA (i.e., MOA per methanotophic cell) was measured on stabilised compost, a commonly used cover in landfills, and on graphite granules, an inert substratum widely used in microbial electrosynthesis studies. After initially enriching methanotrophs on both substrata, biomass normalised MOA was quantified under excess oxygen and limiting methane conditions in 160ml serum vials on both substrata and blends of the substrata. Biomass concentration was measured using the bicinchoninic acid assay for microbial protein. The biomass normalised MOA was consistent across all compost-to-graphite granules blends, but varied with time, reflecting the growth phase of the microorganisms. The biomass normalised MOA ranged from 0.069±0.006μmol CH4/mg dry biomass/h during active growth, to 0.024±0.001μmol CH4/mg dry biomass/h for established biofilms regardless of the substrata employed, indicating the substrata were equally effective in terms of inherent composition. The correlation of MOA with biomass is consistent with studies on methanotrophic activity in natural systems, but biomass normalised MOA varies by over 5 orders of magnitude between studies. This is partially due to different methods being used to quantify biomass, such as pmoA gene quantification and the culture dependent Most Probable Number method, but also indicates that long term exposure of materials to a supply of methane in an aerobic environment, as can occur in natural systems, leads to the enrichment and adaptation of types suitable for those conditions. PMID:27515185

  7. HTO and OBT activity concentrations in soil at the historical atmospheric HT release site (Chalk River Laboratories).

    PubMed

    Kim, S B; Bredlaw, M; Korolevych, V Y

    2012-01-01

    Tritium is routinely released by the Chalk River Laboratories (CRL) nuclear facilities. Three International HT release experiments have been conducted at the CRL site in the past. The site has not been disturbed since the last historical atmospheric testing in 1994 and presents an opportunity to assess the retention of tritium in soil. This study is devoted to the measurement of HTO and OBT activity concentration profiles in the subsurface 25 cm of soil. In terms of soil HTO, there is no evidence from the past HT release experiments that HTO was retained. The HTO activity concentration in the soil pore water appears similar to concentrations found in background areas in Ontario. In contrast, OBT activity concentrations in soil at the same site were significantly higher than HTO activity concentrations in soil. Elevated OBT appears to reside in the top layer of the soil (0-5 cm). In addition, OBT activity concentrations in the top soil layer did not fluctuate much with season, again, quite in contrast with soil HTO. This result suggests that OBT activity concentrations retained the signature of the historical tritium releases.

  8. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation

    PubMed Central

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M.; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R.; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  9. Activity concentrations of (137)Caesium and (210)Polonium in seafood from fishing regions of New Zealand and the dose assessment for seafood consumers.

    PubMed

    Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

    2016-01-01

    A study was undertaken to determine activity concentrations for (134)Caesium, (137)Caesium and (210)Polonium in New Zealand seafood, and establish if activity concentrations varied with respect to species/ecological niche and coastal region. Thirty seafood samples were obtained from six fishing regions of New Zealand along with a further six samples of two commercially important species (hoki and arrow squid) with well-defined fisheries. (134)Caesium was not detected in any sample. (137)Caesium was detected in 47% of samples, predominantly in pelagic fish species, with most activities at a trace level. Detections of (137)Caesium were evenly distributed across all regions. Activity concentrations were consistent with those expected from the oceanic inventory representing residual fallout from global nuclear testing. (210)Polonium was detected above the minimum detectable concentration in 33 (92%) of the analysed samples. Molluscs displayed significantly elevated activity concentrations relative to all other species groups. No significant regional variation in activity concentrations were determined. Two dose assessment models for high seafood consumers were undertaken. Dose contribution from (137)Caesium was minimal and far below the dose exemption limit of 1 mSv/year. Exposure to (210)Polonium was significant in high seafood consumers at 0.44-0.77 mSv/year (5th-95th percentile). (137)Caesium is concluded to be a valuable sentinel radionuclide for monitoring anthropogenic releases, such as global fallout and reactor releases, in the marine environment. (210)Polonium is of importance as a natural radionuclide sentinel due to its high contribution to dietary committed dose in seafood consumers.

  10. Activity concentrations of (137)Caesium and (210)Polonium in seafood from fishing regions of New Zealand and the dose assessment for seafood consumers.

    PubMed

    Pearson, Andrew J; Gaw, Sally; Hermanspahn, Nikolaus; Glover, Chris N

    2016-01-01

    A study was undertaken to determine activity concentrations for (134)Caesium, (137)Caesium and (210)Polonium in New Zealand seafood, and establish if activity concentrations varied with respect to species/ecological niche and coastal region. Thirty seafood samples were obtained from six fishing regions of New Zealand along with a further six samples of two commercially important species (hoki and arrow squid) with well-defined fisheries. (134)Caesium was not detected in any sample. (137)Caesium was detected in 47% of samples, predominantly in pelagic fish species, with most activities at a trace level. Detections of (137)Caesium were evenly distributed across all regions. Activity concentrations were consistent with those expected from the oceanic inventory representing residual fallout from global nuclear testing. (210)Polonium was detected above the minimum detectable concentration in 33 (92%) of the analysed samples. Molluscs displayed significantly elevated activity concentrations relative to all other species groups. No significant regional variation in activity concentrations were determined. Two dose assessment models for high seafood consumers were undertaken. Dose contribution from (137)Caesium was minimal and far below the dose exemption limit of 1 mSv/year. Exposure to (210)Polonium was significant in high seafood consumers at 0.44-0.77 mSv/year (5th-95th percentile). (137)Caesium is concluded to be a valuable sentinel radionuclide for monitoring anthropogenic releases, such as global fallout and reactor releases, in the marine environment. (210)Polonium is of importance as a natural radionuclide sentinel due to its high contribution to dietary committed dose in seafood consumers. PMID:26272653

  11. Effect of recombinant human follicle-stimulating hormone and luteinizing hormone on in vitro maturation of porcine oocytes evaluated by the subsequent in vitro development of embryos obtained by in vitro fertilization, intracytoplasmic sperm injection, or parthenogenetic activation.

    PubMed

    Silvestre, M A; Alfonso, J; García-Mengual, E; Salvador, I; Duque, C C; Molina, I

    2007-05-01

    The aim of this work was to study the effect of recombinant human (rh) FSH and LH on in vitro maturation of pig oocytes compared with a conventional hormonal supplement based on equine (PMSG) and human chorionic gonadotropins (hCG), as evaluated by the developmental ability of 3 types of pig embryos obtained by in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or artificial activation (ATA). In Exp. 1, one cumulus-oocyte complex group (A group) was supplemented with rh-FSH and rh-LH (0.1 IU/mL each), and the other group (B group) was supplemented with PMSG and hCG (10 IU/mL each). No differences in nuclear maturation between the A and B groups were observed (68.5 vs. 71.4%, respectively). No differences were detected between hormonal treatments in the rates of cleavage or blastocyst formation of ATA, IVF, and ICSI embryos. Total cell number of the embryos was not significantly different in any experimental group (A: 31.1, 28.5, and 19.8 vs. B: 25.2, 25.5, and 20.6 for ATA, IVF, and ICSI embryos, respectively). In Exp. 2, the effects of different concentrations of rh-FSH and rh-LH (0.5, 0.1, or 0.05 IU/mL) in maturation medium on nuclear maturation and in vitro development of embryos obtained by IVF were studied. No effect of different hormonal concentrations on blastocyst formation rates was observed (8.5, 13.0, and 5.7%, respectively). Blastocyst cell number was not different in any experimental group. In conclusion, the results obtained here permit us to substitute PMSG and hCG with rh-FSH and rh-LH and to produce pig embryos obtained by IVF, ICSI, or ATA.

  12. Enhanced photocatalytic activity of TiO2-impregnated with MgZnAl mixed oxides obtained from layered double hydroxides for phenol degradation

    NASA Astrophysics Data System (ADS)

    de Almeida, Marciano Fabiano; Bellato, Carlos Roberto; Mounteer, Ann Honor; Ferreira, Sukarno Olavo; Milagres, Jaderson Lopes; Miranda, Liany Divina Lima

    2015-12-01

    A series of TiO2/MgZnAl photocatalysts were successfully synthesized from ternary (Mg, Zn and Al) layered double hydroxides impregnated with TiO2 nanoparticles by the co-precipitation method at variable pH with different Zn2+/Mg2+ molar ratios. The composite photocatalysts were calcined at 500 °C resulting in the incorporation of oxide zinc, in the calcined MgZnAl LDH structure. Synergistic effect between ZnO and TiO2 lead to significant enhancement of TiO2/MgZnAl photocatalytic activity. Composite photocatalysts were characterized by ICP-MS, N2 adsorption-desorption, XRD, SEM, EDS, IR and UV-vis DRS. Phenol in aqueous solution (50 mg/L) was used as a model compound for evaluation of UV-vis (filter cut-off for λ > 300 nm) photocatalytic activity. The most efficient photocatalyst composite was obtained at a 5% Zn2+/Mg2+ molar ratio, in the catalyst identified as TiO2/MgZnAl-5. This composite catalyst had high photocatalytic activity, completely destroying phenol and removing 80% of total organic carbon in solution after 360 min. The TiO2/MgZnAl-5 catalyst remained relatively stable, presenting a 15% decrease in phenol degradation efficiency after five consecutive photocatalytic cycles.

  13. Prototype of a primary calibration system for measurement of radon activity concentration.

    PubMed

    Mostafa, M Y A; Vasyanovich, M; Zhukovsky, M

    2016-01-01

    To calibrate measurement devices for monitoring the activity concentration of (222)Rn in air, a prototype of a calibration facility is tested using a solid (226)Ra source and a high-purity germanium (HPGe) detector. An emanation box was mounted on the detector for online gamma measurements. Inside this box, a 32.8 kBq ±3% (226)Ra standard source was placed. An AlphaGUARD control radon monitor was connected to the emanation box with a pumping air system in an open flow mode as a reference monitor. The emanation coefficient of the source was controlled online by comparing the gamma activity of (214)Bi (Eγ=609.3 keV), progeny of (226)Ra, to that of the calibration source. A standard (137)Cs source, installed within the emanation box, was used as a reference for gamma spectroscopy using the HPGe detector, with a total systematic error of 4% and a random error less than 2%. The ratio between gamma measurements and AlphaGUARD was 0.94±0.4; which is within the 9% uncertainties of AlphaGUARD calibration. PMID:26490512

  14. Predicting the activity coefficients of free-solvent for concentrated globular protein solutions using independently determined physical parameters.

    PubMed

    McBride, Devin W; Rodgers, Victor G J

    2013-01-01

    The activity coefficient is largely considered an empirical parameter that was traditionally introduced to correct the non-ideality observed in thermodynamic systems such as osmotic pressure. Here, the activity coefficient of free-solvent is related to physically realistic parameters and a mathematical expression is developed to directly predict the activity coefficients of free-solvent, for aqueous protein solutions up to near-saturation concentrations. The model is based on the free-solvent model, which has previously been shown to provide excellent prediction of the osmotic pressure of concentrated and crowded globular proteins in aqueous solutions up to near-saturation concentrations. Thus, this model uses only the independently determined, physically realizable quantities: mole fraction, solvent accessible surface area, and ion binding, in its prediction. Predictions are presented for the activity coefficients of free-solvent for near-saturated protein solutions containing either bovine serum albumin or hemoglobin. As a verification step, the predictability of the model for the activity coefficient of sucrose solutions was evaluated. The predicted activity coefficients of free-solvent are compared to the calculated activity coefficients of free-solvent based on osmotic pressure data. It is observed that the predicted activity coefficients are increasingly dependent on the solute-solvent parameters as the protein concentration increases to near-saturation concentrations.

  15. Effect of two dietary concentrate levels on tenderness, calpain and calpastatin activities, and carcass merit in Waguli and Brahman steers.

    PubMed

    Ibrahim, R M; Goll, D E; Marchello, J A; Duff, G C; Thompson, V F; Mares, S W; Ahmad, H A

    2008-06-01

    The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values

  16. Effect of two dietary concentrate levels on tenderness, calpain and calpastatin activities, and carcass merit in Waguli and Brahman steers.

    PubMed

    Ibrahim, R M; Goll, D E; Marchello, J A; Duff, G C; Thompson, V F; Mares, S W; Ahmad, H A

    2008-06-01

    The objective of this study was to compare carcass characteristics of a newly introduced breed, the Waguli (Wagyu x Tuli), with the carcass characteristics of the Brahman breed. Brahman cattle are used extensively in the Southwest of the United States because of their tolerance to adverse environmental conditions. However, Brahman carcasses are discounted according to the height of their humps because of meat tenderness issues. The Waguli was developed in an attempt to obtain a breed that retained the heat tolerance of the Brahman but had meat quality attributes similar to the Wagyu. Twenty-four animals were used. Six steers from each breed were fed a 94% concentrate diet and 6 steers from each breed were fed an 86% concentrate diet. Eight steers, 2 from each group, were harvested after 128 d, after 142 d, and after 156 d on feed. Waguli steers had larger LM, greater backfat thickness, greater marbling scores, and greater quality grades than the Brahman steers (P < 0.05). The Japanese Wagyu breed is well known for its highly marbled and tender meat, and these traits are also present in the Waguli. The Waguli had significantly lower Warner-Bratzler shear force values than the Brahman steers after 7 and 10 d of postmortem aging (P < 0.05); this difference decreased after 14 d postmortem (P = 0.2), when tenderness of the slower aging Brahman had increased to acceptable levels. Toughness of the Brahman has been associated with high levels of calpastatin in Brahman muscle, and the Waguli LM had significantly less calpastatin activity (P = 0.02) at 0 h postmortem than the Brahman LM. At 0-h postmortem, the total LM calpain activity did not differ between the Brahman and Waguli (P = 0.57). Neither diet nor days on feed had any significant effect on the 0-h postmortem calpain or at 0-h postmortem calpastatin activity, nor an effect on Warner-Bratzler shear-force values. In conclusion, LM muscle from the Waguli steers had a high degree of marbling, lower shear force values

  17. Growth inhibitory activities of crude extracts obtained from herbal plants in the Ryukyu Islands on several human colon carcinoma cell lines.

    PubMed

    Kaneshiro, Tatsuya; Suzui, Masumi; Takamatsu, Reika; Murakami, Akira; Ohigashi, Hajime; Fujino, Tetsuya; Yoshimi, Naoki

    2005-01-01

    There is increasing interest in the use of herbs for the treatment of human diseases including cancer. Therefore, the purpose of this study was to determine whether crude extracts obtained from 44 herbal plants in the Ryukyu Islands might contain components capable of inhibiting the growth of a variety of human colon carcinoma cell lines. Leaves, roots and other parts of the plants were extracted with chloroform, and the crude extracts were dissolved in dimethylsulfoxide and used for the experiments. Extracts of Hemerocallis fulva, Ipomoea batatas, Curcuma longa, and Nasturium officinale caused marked dose-dependent growth inhibition, with IC(50) values in the range of 10-80 mug/ml. With the HCT116 cell line, the extracts of Hemerocallis fulva and Ipomoea batatas induced G1 cell cycle arrest after 48 h of treatment. In addition, we found that extracts of Curcuma longa, and Nasturium officinale induced apoptosis in these cells after 48 h of treatment. The present studies are the first systematic examination of the growth inhibitory effects of crude extracts obtained from herbal plants in the Ryukyu Islands. The findings provide evidence that several plants in the Ryukyu Islands contain components that may have anticancer activity. PMID:16235999

  18. Association of circulating active and total ghrelin concentrations with dry matter intake, growth, and carcass characteristics of finishing beef cattle.

    PubMed

    Foote, A P; Hales, K E; Lents, C A; Freetly, H C

    2014-12-01

    Ghrelin is a gut peptide that when acylated is thought to stimulate appetite. Circulating ghrelin concentrations could potentially be used as a predictor of DMI in cattle. The objective of this experiment was to determine the association of circulating ghrelin concentrations with DMI and other production traits. Steers and heifers were fed a finishing diet, and individual intake was recorded for 84 d. Blood samples were collected via jugular venipuncture following the DMI and ADG measurement period. Plasma active ghrelin and total ghrelin were quantified using commercial RIA. Active ghrelin was not correlated to DMI (P=0.36), but when DMI was modeled using a multivariate analysis including plasma metabolites and sex, active ghrelin was shown to be positively associated with DMI (P<0.01) and accounted for 6.2% of the variation accounted for by the regression model (R2=0.33). Total ghrelin was negatively correlated to DMI (P<0.01), but was not significant in a multivariate regression analysis (P=0.13). The ratio of active:total ghrelin was positively associated with DMI (P<0.01) and accounted for 10.2% of the variation in the model (R2=0.35). Active ghrelin was positively associated with ADG (P<0.05), while total ghrelin was negatively associated with ADG (P<0.01), and the ratio of active:total ghrelin was positively associated with ADG (P<0.01). Active ghrelin was not associated with G:F (P=0.88), but total ghrelin concentrations were negatively associated with G:F (P<0.01) and accounted for 10.24% of the variation (R2=0.25). Heifers consumed less feed than steers (P<0.01), tended to have greater active ghrelin concentrations (P=0.06), and had greater total ghrelin concentrations than steers (P=0.04). Total ghrelin concentrations were not different between sire breeds (P=0.80), but active ghrelin concentrations and the ratio of active:total ghrelin differed between breeds (P<0.01), indicating that genetics have an effect on the amount and form of circulating ghrelin

  19. Radioactivity and metal concentrations in marine sediments associated with mining activities in Ierissos Gulf, North Aegean Sea, Greece.

    PubMed

    Pappa, F K; Tsabaris, C; Ioannidou, A; Patiris, D L; Kaberi, H; Pashalidis, I; Eleftheriou, G; Androulakaki, E G; Vlastou, R

    2016-10-01

    Marine sediment samples were collected from Ierissos Gulf, N Aegean Sea, close to the coastal mining facilities. Measurements of radionuclide and metal concentrations, mineral composition and grain size distribution were performed. The concentrations of (226)Ra, (235)U and trace metals showed enhanced values in the port of Stratoni compared with those obtained near to Ierissos port. The dose rates received by marine biota were also calculated by the ERICA Assessment Tool and the results indicated no significant radiological risk. PMID:27474903

  20. Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

    SciTech Connect

    Rawl, Richard R; Scofield, Patricia A; Leggett, Richard Wayne; Eckerman, Keith F

    2010-04-01

    The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low-level NORM

  1. Selenium concentrations and enzyme activities of glutathione metabolism in wild long-tailed ducks and common eiders

    USGS Publications Warehouse

    Franson, J. Christian; Hoffman, David J.; Flint, Paul L.

    2011-01-01

    The relationships of selenium (Se) concentrations in whole blood with plasma activities of total glutathione peroxidase, Se-dependent glutathione peroxidase, and glutathione reductase were studied in long-tailed ducks (Clangula hyemalis) and common eiders (Somateria mollissima) sampled along the Beaufort Sea coast of Alaska, USA. Blood Se concentrations were >8 μg/g wet weight in both species. Linear regression revealed that the activities of total and Se-dependent glutathione peroxidase were significantly related to Se concentrations only in long-tailed ducks, raising the possibility that these birds were experiencing early oxidative stress.

  2. Fine organic particle, formaldehyde, acetaldehyde concentrations under and after the influence of fire activity in the atmosphere of Riverside, California.

    PubMed

    Na, Kwangsam; Cocker, David R

    2008-09-01

    Concentrations of gas-phase organic carbons (formaldehyde (HCHO) and acetaldehyde (CH(3)CHO)) and fine particle-phase carbons (organic carbon (OC) and elemental carbon (EC)) were measured under and after the influence of fire activity in southern California. The measurement was conducted after the start of the wildfire activities from October 27 through November 6, 2003 at a site in Riverside, southern California. Under the influence of the fire activities, HCHO, CH(3)CHO and EC concentrations were found to be over two times as high as those after the fire activities ended. The total lifetime cancer risk estimated by HCHO and CH(3)CHO concentrations measured was significantly higher under the influence of the wildfire activities than that after the activities ended. OC showed a larger difference in concentrations between the two event periods as compared with gas-phase organic carbons and EC. OC/EC ratios ranged from 3.7 to 12.5 during the study period with the highest OC/EC ratio observed when the study area was under the influence of the fire activities. Correlation analysis and multiple linear regressions between OC/EC concentrations and visibility were performed. It was found that the visibility was even worse under the influence of fire activity as compared to the period after fire activity ended. EC was a stronger contributor to the visibility reduction compared to OC. The influence of air mass pathways on HCHO, CH(3)CHO, OC, and EC concentrations during the wildfire activities was addressed using a backward trajectory model developed by NOAA.

  3. Busulphan is active against neuroblastoma and medulloblastoma xenografts in athymic mice at clinically achievable plasma drug concentrations

    PubMed Central

    Boland, I; Vassal, G; Morizet, J; Terrier-Lacombe, M-J; Valteau-Couanet, D; Kalifa, C; Hartmann, O; Gouyette, A

    1999-01-01

    High-dose busulphan-containing chemotherapy regimens have shown high response rates in children with relapsed or refractory neuroblastoma, Ewing's sarcoma and medulloblastoma. However, the anti-tumour activity of busulfan as a single agent remains to be defined, and this was evaluated in athymic mice bearing advanced stage subcutaneous paediatric solid tumour xenografts. Because busulphan is highly insoluble in water, the use of several vehicles for enteral and parenteral administration was first investigated in terms of pharmacokinetics and toxicity. The highest bioavailability was obtained with busulphan in DMSO administered i.p. When busulphan was suspended in carboxymethylcellulose and given orally or i.p., the bioavailability was poor. Then, in the therapeutic experiments, busulphan in DMSO was administered i.p. on days 0 and 4. At the maximum tolerated total dose (50 mg kg−1), busulphan induced a significant tumour growth delay, ranging from 12 to 34 days in the three neuroblastomas evaluated and in one out of three medulloblastomas. At a dose level above the maximum tolerated dose, busulphan induced complete and partial tumour regressions. Busulphan was inactive in a peripheral primitive neuroectodermal tumour (PNET) xenograft. When busulphan pharmacokinetics in mice and humans were considered, the estimated systemic exposure at the therapeutically active dose in mice (113 μg h ml−1) was close to the mean total systemic exposure in children receiving high-dose busulphan (102.4 μg h ml−1). In conclusion, busulphan displayed a significant anti-tumour activity in neuroblastoma and medulloblastoma xenografts at plasma drug concentrations which can be achieved clinically in children receiving high-dose busulphan-containing regimens. 1999 Cancer Research Campaign PMID:10070870

  4. The Comparative Analysis of Antioxidant and Biological Activity for the Dendropanax morbifera LEV. Leaves Extracted by Different Ethanol Concentrations.

    PubMed

    Nakamura, Masaya; Ra, Jong-Hwan; Kim, Ju-Sung

    2016-01-01

    The different concentrations of ethanol (20-100%) and distilled water extract for Dendropanax morbifera LEV. leaves were evaluated to induce antioxidant and biological activity employed by variety of assays. The 20%, 80%, and 100% ethanol extract demonstrated the relatively higher activity, whereas distilled water, 40%, and 60% ethanol extracts exhibited the lower antioxidant and biological activity. Especially, 80% ethanol extract showed the remarkably higher radical scavenging activity, reducing power, total phenol and flavonoid content, α-glucosidase, and tyrosinase inhibitory activity, and alcohol dehydrogenases (ADH) and aldehyde dehydrogenase (ALDH) activity. Also, 100% ethanol extract exhibited relatively greater activity, but there did not show significant radical scavenging activity. Furthermore, there were 50% and 30% promotion effect for ADH activity assay and 80% and 40% promotion effect for ALDH activity assay in 80% and 100% ethanol extract, respectively. In addition, in the minimum inhibitory concentration (MIC), all extracts except for distilled water extract inhibited Bacillus cereus, Staphylococcus aureus subsp. aureus, Escherichia coli. For Pichia jadinii, whole extracts effectively inhibited yeast multiplication at concentration of 125 μg/mL for 100% ethanol extract and 250 μg/mL for the rest of extract. These result indicated that D. morbifera LEV. leaves extracted by 80% ethanol would be the ideal extracting solution to maximize inherent antioxidant and biological activity agent. PMID:27592831

  5. Effects of Hemerocallis flava on motor activity and the concentration of central monoamines and its metabolites in rats.

    PubMed

    Hsieh, M T; Ho, Y F; Peng, W H; Wu, C R; Chen, C F

    1996-06-01

    In this study, we used behavioral and biochemical methods to investigate the effects of Hemerocallis flava (Liliaceae) (abbreviated as HF) on motor activity and the concentration of monoamines in rats. The water fraction of the resuspended HF extract was most active in reducing the motility in rats. The water fraction of the HF extract enhanced the reduction of locomotor activity produced by alpha-methyl-p-tyrosine and 5-hydroxytryptophan, but it reduced the increase of locomotor activity produced by L-dopa plus benserazide and p-chlorophenylalanine. Furthermore, the water fraction of the HF extract significantly decreased the concentration of norepinepherine in the cortex and the concentration of dopamine and serotonin in the brain stem. It also increased the concentration of vanilylmandelic acid in the cortex, homovanillic acid and 5-hydroxyindole-acetic acid in the brain stem. These results suggest that the reduction of locomotor activity produced by the water fraction of HF extract may be related to the decrease in the concentration of norepinepherine in the cortex and the concentration of dopamine and serotonin in brain stem. PMID:8735450

  6. Activation of ENaC by AVP contributes to the urinary concentrating mechanism and dilution of plasma.

    PubMed

    Mironova, Elena; Chen, Yu; Pao, Alan C; Roos, Karl P; Kohan, Donald E; Bugaj, Vladislav; Stockand, James D

    2015-02-01

    Arginine vasopressin (AVP) activates the epithelial Na(+) channel (ENaC). The physiological significance of this activation is unknown. The present study tested if activation of ENaC contributes to AVP-sensitive urinary concentration. Consumption of a 3% NaCl solution induced hypernatremia and plasma hypertonicity in mice. Plasma AVP concentration and urine osmolality increased in hypernatremic mice in an attempt to compensate for increases in plasma tonicity. ENaC activity was elevated in mice that consumed 3% NaCl solution compared with mice that consumed a diet enriched in Na(+) with ad libitum tap water; the latter diet does not cause hypernatremia. To determine whether the increase in ENaC activity in mice that consumed 3% NaCl solution served to compensate for hypernatremia, mice were treated with the ENaC inhibitor benzamil. Coadministration of benzamil with 3% NaCl solution decreased urinary osmolality and increased urine flow so that urinary Na(+) excretion increased with no effect on urinary Na(+) concentration. This decrease in urinary concentration further increased plasma Na(+) concentration, osmolality, and AVP concentration in these already hypernatremic mice. Benzamil similarly compromised urinary concentration in water-deprived mice and in mice treated with desmopressin. These results demonstrate that stimulation of ENaC by AVP plays a critical role in water homeostasis by facilitating urinary concentration, which can compensate for hypernatremia or exacerbate hyponatremia. The present findings are consistent with ENaC in addition to serving as a final effector of the renin-angiotensin-aldosterone system and blood pressure homeostasis, also playing a key role in water homeostasis by regulating urine concentration and dilution of plasma. PMID:25391898

  7. Effect of various concentration of sulfuric acid for Nafion membrane activation on the performance of fuel cell

    NASA Astrophysics Data System (ADS)

    Pujiastuti, Sri; Onggo, Holia

    2016-02-01

    This work proposes an activation treatment to Nafion 117 membrane with sulfuric acid in various concentrations. The main goal of this study is to increase the Nafion 117 membrane performance, which is determined by proton number in the membrane and membrane performance in Polymer Electrolyte Membrane Fuel Cell (PEMFC). This work was developed using sulfuric acids in four different concentrations: 1, 2, 3, and 4 M. The surface morphology and functional groups of activated membranes were studied using Scanning Electron Microscope and Fourier Transform Infrared, respectively. The proton number absorbed in membranes was observed by gravimetric measurements. The performances of activated membranes in PEMFC were studied by single cell measurements with H2/O2 operation. The experimental results showed that activation of Nafion membrane did not change its surface morphology and functional groups. The proton number increased when the concentration of sulfuric acid is increased from 1 to 3 M and from 1 to 4 M. On the other hand, there is no significant increase when the concentration of sulfuric acid was increased from 1 to 2 M. Similar trends were observed when testing activated membrane performance in PEMFC, especially for current density at 0.6 V and maximum power. It is assumed that there is a correlation between the increase of sulfuric acid concentration in activation process with the increase of proton number in the membrane that are available for facilitating of transfer protons from the anode to the cathode.

  8. Sulforhodamine 101, a widely used astrocyte marker, can induce cortical seizure-like activity at concentrations commonly used

    PubMed Central

    Rasmussen, Rune; Nedergaard, Maiken; Petersen, Nicolas Caesar

    2016-01-01

    Sulforhodamine 101 (SR101) is a preferential astrocyte marker widely used in 2-photon microscopy experiments. Here we show, that topical loading of two commonly used SR101 concentrations, 100 μM and 250 μM when incubated for 10 min, can induce seizure-like local field potential (LFP) activity in both anaesthetized and awake mouse sensori-motor cortex. This cortical seizure-like activity develops in less than ten minutes following topical loading, and when applied longer, these neuronal discharges reliably evoke contra-lateral hindlimb muscle contractions. Short duration (<1 min) incubation of 100 μM and 250 μM SR101 or application of lower concentrations 25 μM and 50 μM of SR101, incubated for 30 and 20 min, respectively, did not induce abnormal LFP activity in sensori-motor cortex, but did label astrocytes, and may thus be considered more appropriate concentrations for in vivo astrocyte labeling. In addition to label astrocytes SR101 may, at 100 μM and 250 μM, induce abnormal neuronal activity and interfere with cortical circuit activity. SR101 concentration of 50 μM or lower did not induce abnormal neuronal activity. We advocate that, to label astrocytes with SR101, concentrations no higher than 50 μM should be used for in vivo experiments. PMID:27457281

  9. Anaemia, Serum Iron Concentrations and δ-Aminolevulinate Dehydratase Activity in Laying Hens Infected Naturally by Salmonella Gallinarum.

    PubMed

    Machado, A C; Boiago, M M; do Carmo, G M; Bottari, N B; Araujo, D N; Giuriatti, J; Morsch, V M; Schetinger, M R C; Casagrande, R A; Wisser, C S; Stefani, L M; Alves, M S; Da Silva, A S

    2016-07-01

    The aim of this study was to evaluate anaemia, serum iron concentrations and δ-aminolevulinate dehydratase (ALA-D) activity in laying hens infected naturally by Salmonella Gallinarum and having severe hepatic lesions. Liver and serum samples were collected from 27 laying hens (20 infected and seven uninfected). The δ-ALA-D activity, haematocrit and serum iron concentrations were evaluated. There were significant decreases in δ-ALA-D activity, haematocrit and serum iron concentrations (P <0.01) in birds infected by S. Gallinarum when compared with uninfected birds. There was a positive correlation (P <0.001) between serum iron concentration, haematocrit (r(2) = 0.82) and δ-ALA-D activity (r(2) = 0.75). A positive correlation was also observed between δ-ALA-D activity and haematocrit (r(2) = 0.78; P <0.01). Liver samples showed moderate focal coagulative necrosis associated with infiltration of lymphoplasmacytic cells, macrophages and heterophils. The anaemia in the infected hens may be related to reduction in δ-ALA-D activity and serum iron concentrations, since both are important for haemopoiesis.

  10. Responses of methanotrophic activity, community and EPS production to CH4 and O2 concentrations in waste biocover soils.

    PubMed

    Wei, Xiao-Meng; Su, Yao; Zhang, Hong-Tao; Chen, Min; He, Ruo

    2015-08-01

    Biocover soils are known to be a good alternative material to mitigate CH4 emissions from landfills to the atmosphere. In this study, 16 treatments with four O2 concentrations (∼0%, 5%, 10% and 21%) and four CH4 concentrations (i.e. 1%, 10%, 20% and 50%) were conducted to estimate extracellular polymeric substances (EPS) production, methanotrophic activity and community in response to CH4 and O2 concentrations in waste biocover soil (WBS). When the CH4 concentration was saturated for CH4 oxidation in the WBS, the continuous exposure of CH4 above the saturated concentrations could not obviously enhance CH4 oxidation activity. In the WBS, extracellular protein (ECP) production was negatively related with the tested CH4 concentrations, while both ECP and extracellular polysaccharides (ECPS) productions were positively related with the tested O2 concentrations. Cloning and terminal restriction fragment length polymorphism analyses showed that type I methanotrophs (Methylocaldum, Methylococcaceae, Methylomicrobium and Methylobacter) and type II methanotrophs (Methylosinus) dominated in the WBS. Among them, Methylocaldum and/or Methylococcaceae were sensitive to low O2 concentrations of ∼0%. Methylobacter had propensity to grow at low O2 concentrations of ∼0% and 5%, while Methylosinus preferred environments with high concentrations of CH4 (⩾10%) and O2 (21%). In the tested five environmental variables of ECPS, O2, EPS, CH4 and ECP, only ECPS and O2 concentrations had significant effect on the methanotrophic communities. These results suggested that O2 concentration in landfill covers should be paid more attention to optimize and sustain CH4 oxidation for mitigating CH4 emission from landfills.

  11. [Effect of continual application of two kinds sludge on enzyme activities and heavy metal concentrations in alluvial soil].

    PubMed

    Tan, Qiling; Hu, Chengxiao; Zhao, Bin; Mclaren, R G; Cheng, Li; Wu, Lishu

    2004-03-01

    Pot culture experiments were conducted to study the effect of industrial and sewage sludge on some enzyme activities and heavy metal concentrations in alluvial soil. The results showed that the heavy metals in both industrial and sewage sludge were mainly non-exchangeable, and those in sewage sludge had a lower concentration but a higher bio-availability than in industrial sludge. The application of sludge could increase the activities of soil urease, polyphenol oxidase and neutral phosphatase, and the polyphenol oxidase and neutral phosphatase activities showed a reverse relationship with the concentrations of soil exchangeable Zn and Cu. Soil polyphenol oxidase and catalase activities could be used to indicate the Zn pollution in soil.

  12. Regional Influences of Marcellus Shale Natural Gas Activity: Back-trajectory Analysis of Baltimore/Washington Ethane Concentrations

    NASA Astrophysics Data System (ADS)

    Vinciguerra, T.; Chittams, A.; Dadzie, J.; Deskins, T.; Goncalves, V.; M'Bagui Matsanga, C.; Zakaria, R.; Ehrman, S.; Dickerson, R. R.

    2015-12-01

    Over the past several years, the combined utilization of hydraulic fracturing and horizontal drilling has led to a rapid increase in natural gas production, especially from the Marcellus Shale. To explore the impact of this activity downwind on regions with no natural gas production, the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) Model was used to generate 48-hour back-trajectories for summer, daytime hours from the years 2007-2014 in the Baltimore, MD and Washington, D.C. areas where hourly ethane measurements are available from Photochemical Assessment Monitoring Stations (PAMS). For each of the years investigated, unconventional well counts were obtained for counties in the surrounding states of Pennsylvania, Ohio, West Virginia, and Virginia, and counties exceeding a threshold of 0.05 wells/km2 were designated as counties with a high density of wells. The back-trajectories for each year were separated into two groups: those which passed through counties containing a high density of wells, and those which did not. Back-trajectories passing through high-density counties were further screened by applying a height criterion where trajectories beyond 10% above the mixing layer were excluded. Preliminary results indicate that air parcels with back-trajectories passing within the boundary layer of counties with a high density of unconventional natural gas wells correspond to significantly greater concentrations of observed ethane at these downwind monitors.

  13. Ethanol-Induced ADH Activity in Zebrafish: Differential Concentration-Dependent Effects on High- Versus Low-Affinity ADH Enzymes.

    PubMed

    Tran, Steven; Nowicki, Magda; Facciol, Amanda; Chatterjee, Diptendu; Gerlai, Robert

    2016-04-01

    Zebrafish express enzymes that metabolize ethanol in a manner comparable to that of mammals, including humans. We previously demonstrated that acute ethanol exposure increases alcohol dehydrogenase (ADH) activity in an inverted U-shaped dose-dependent manner. It was hypothesized that the biphasic dose-response was due to the increased activity of a high-affinity ADH isoform following exposure to low concentrations of ethanol and increased activity of a low-affinity ADH isoform following exposure to higher concentrations of ethanol. To test this hypothesis, we exposed zebrafish to different concentrations of ethanol (0%, 0.25%, 0.5%, and 1.0% v/v) for 30 min and measured the total ADH activity in the zebrafish liver. However, we also repeated this enzyme activity assay using a low concentration of the substrate (ethanol) to determine the activity of high-affinity ADH isoforms. We found that total ADH activity in response to ethanol induces an inverted U-shaped dose-response similar to our previous study. Using a lower substrate level in our enzyme assay targeting high-affinity isozymes, we found a similar dose-response. However, the difference in activity between the high and low substrate assays (high substrate activity - low substrate activity), which provide an index of activity for low-affinity ADH isoforms, revealed no significant effect of ethanol exposure. Our results suggest that the inverted U-shaped dose-response for total ADH activity in response to ethanol is driven primarily by high-affinity isoforms of ADH.

  14. Anti-inflammatory and antioxidant activities, functional properties and mutagenicity studies of protein and protein hydrolysate obtained from Prosopis alba seed flour.

    PubMed

    Cattaneo, Florencia; Sayago, Jorge Esteban; Alberto, María Rosa; Zampini, Iris Catiana; Ordoñez, Roxana Mabel; Chamorro, Verónica; Pazos, Adriana; Isla, María Inés

    2014-10-15

    Prosopis species are considered multipurpose trees and shrubs by FAO and their fruit constitute a food source for humans and animals. According to the "Código Alimentario Argentino", "algarrobo flour" is produced by grinding the whole mature pod, but in the traditional process most of the seeds are discarded. In this paper, the flour from seed was obtained. Then, the proteins were extracted and enzymatic hydrolysis was carried out. According to their amino acid profile and chemical score (>100%), the Prosopis alba proteins, are not deficient in essential amino acids considering the amount of amino acid necessary by adults. The protein isolate showed a good solubility (pH 7.4-9), emulsificant capacity, oil binding capacity and water adsorption capacity. The antioxidant ability of proteins was significantly increased with hydrolysis (SC50 values: 50-5μg/mL, respectively). Inhibitory activity of pro-inflammatory enzymes (lipoxygenase and phospholipase) was described. The mutagenicity/antimutagenicity of proteins and protein hydrolysates from seed flour were also analysed. The results suggest that P. alba cotyledon flour could be a new alternative in the formulation of functional foods not only for its high protein content but also by the biological and functional properties of its proteins and protein hydrolysates.

  15. Characterization of concentration gradients of a morphogenetically active retinoid in the chick limb bud

    PubMed Central

    1987-01-01

    It has long been suggested that the generation of biological patterns depends in part on gradients of diffusible substances. In an attempt to bridge the gap between this largely theoretical concept and experimental embryology, we have examined the physiology of diffusion gradients in an actual embryonic field. In particular, we have generated in the chick wing bud concentration gradients of the morphogenetically active retinoid TTNPB, (E)-4-[2-(5,6,7,8-tetrahydro- 5,5,8,8-tetramethyl-2-naphthalenyl)-1-prope nyl] benzoic acid, a synthetic vitamin A compound. Upon local application of TTNPB the normal 234 digit pattern is duplicated in a way that correlates with the geometry of the underlying TTNPB gradient; low doses of TTNPB lead to a shallow gradient and an additional digit 2, whereas higher doses result in a steep, far-reaching gradient and patterns with additional digits 3 and 4. The experimentally measured TTNPB distribution along the anteroposterior axis, can be modeled by a local source and a dispersed sink. This model correctly predicts the site of specification of digit 2, and provides an empirical estimate of the diffusion coefficient (D) of retinoids in embryonic limb tissue. The numerical value of approximately 10(-7) cm2s-1 for D suggests that retinoids are not freely diffusible in the limb rudiment, but interact with the previously identified cellular retinoic acid binding protein. In addition, D affords an estimate of the time required to establish a diffusion gradient as 3 to 4 h. This time span is in a range compatible with the time scale of pattern specification in developing vertebrate limbs. Our studies support the view that diffusion of morphogenetic substances is a plausible mechanism of pattern formation in secondary embryonic fields. PMID:3667700

  16. Chemopreventive activity of grape juice concentrate (G8000TM) on rat colon carcinogenesis induced by azoxymethane.

    PubMed

    Silva, Roseane Mendes; Campanholo, Vanessa Maria de Lima Pazine; Paiotti, Ana Paula Ribeiro; Artigiani Neto, Ricardo; Oshima, Celina Tizuko Fujiyama; Ribeiro, Daniel Araki; Forones, Nora Manoukian

    2015-11-01

    Colorectal cancer is the third most common cancer worldwide in both sexes, with similar geographic patterns between genders. This neoplasm has good prognosis if the disease is diagnosed at early stages. The aim of this study was to evaluate the effect of red grape juice on the expression of COX-2 and Ki-67 expression following colon carcinogenesis induced by azoxymethane (AOM). Thirty-five rats were randomly distributed into seven groups (n=5 per group): G1: SHAM or negative control received only saline; G2 (positive control): animals received 15 mg/kg AOM; G3: animals received 1% red grape juice 2 weeks before the administration of AOM; G4: animals received 2% red grape juice 2 weeks before the administration of AOM; G5: animals received 1% red grape juice 4 weeks after the last administration of AOM; G6: animals received 2% red grape juice 4 weeks after the last administration of AOM; G7: animals received only 2% red grape juice. COX-2 mRNA expression was reduced in animals treated with 1% red grape juice before AOM induction or 2% red grape juice after AOM induction. COX-2 immunoexpression was also reduced to groups treated with red grape juice at 1% before and after AOM induction or 2% red grape juice after AOM induction. Decreased immunoexpression of Ki-67 positive cells was observed in animals treated with 1% grape juice before AOM-treated animals. Taken together, grape juice concentrate is able to exert some chemopreventive activity on rat colon carcinogenesis.

  17. Biological effects of short-term, high-concentration exposure to methyl isocyanate. VI. In vitro and in vivo complement activation studies

    SciTech Connect

    Kolb, W.P.; Savary, J.R.; Troup, C.M.; Dodd, D.E.; Tamerius, J.D.

    1987-06-01

    The ability of MIC to induce complement activation in vitro and in vivo was investigated. For the in vitro studies, both human and guinea pig serum or EDTA-plasma samples were exposed to 1167 to 1260 ppm MIC vapor for 15 min at room temperature. The human serum samples exposed to MIC showed significant reduction in Factor B, C2, C4, C3, C5, and total hemolytic complement CH/sub 50/ activity levels. The C3, C5, and CH/sub 50/ functional activities in guinea pig serum were more sensitive to MIC-mediated reduction than the corresponding activity reductions observed in the human serum samples. The human and single guinea pig EDTA-plasma samples exposed to MIC vapor showed no evidence of C3 consumption but did show significant reductions in CH/sub 50/ levels. Thus, MIC vapor was able to active, and thereby reduce serum complement C3 activity in vitro by a complement-dependent process. For the in vivo studies, five pairs of guinea pigs were exposed to 644 to 702 ppm MIC vapor until one of the pair died (11-15 min). MIC exposure was then discontinued, the surviving guinea pig was sacrificed, and EDTA-plasma was obtained from both animals and analyzed for complement consumption. Clear evidence was obtained to indicate that complement activation had occurred in these animals exposed to MIC for 11 to 15 min. In addition, the complement activation profile observed in these guinea pigs was qualitatively similar to that seen in the guinea pig serum samples exposed to MIC vapor in vitro. The total protein concentration present in plasma samples obtained from guinea pigs that had died from MIC exposure was elevated significantly. The possible contribution of complement activation to the fatal reaction(s) observed in these MIC-treated animals is discussed.

  18. Low Concentration of Silver Nanoparticles Not Only Enhances the Activity of Horseradish Peroxidase but Alter the Structure Also

    PubMed Central

    Karim, Zoheb; Adnan, Rohana; Ansari, Mohd Saquib

    2012-01-01

    Chemical synthesis of Ag-NPs was carried out using reduction method. The reduction mechanistic approach of silver ions was found to be a basic clue for the formation of the Ag-NPs. The nanoparticles were characterized by UV-vis, FT-IR and TEM analysis. We had designed some experiments in support of our hypothesis, “low concentrations of novel nanoparticles (silver and gold) increases the activity of plant peroxidases and alter their structure also”, we had used Ag-NPs and HRP as models. The immobilization/interaction experiment had demonstrated the specific concentration range of the Ag-NPs and within this range, an increase in HRP activity was reported. At 0.08 mM concentration of Ag-NPs, 50% increase in the activity yield was found. The U.V-vis spectra had demonstrated the increase in the absorbance of HRP within the reported concentration range (0.06–0.12 mM). Above and below this concentration range there was a decrease in the activity of HRP. The results that we had found from the fluorescence spectra were also in favor of our hypothesis. There was a maximum increase in ellipticity and α-helix contents in the presence of 0.08 mM concentration of Ag-NPs, demonstrated by circular dichroism (CD) spectra. Finally, incubation of a plant peroxidase, HRP with Ag-NPs, within the reported concentration range not only enhances the activity but also alter the structure. PMID:22848490

  19. Effect of periplasmic expression of recombinant mouse interleukin-4 on hydrogen peroxide concentration and catalase activity in Escherichia coli.

    PubMed

    Mehdizadeh Aghdam, Elnaz; Mahmoudi Azar, Lena; Barzegari, Abolfazl; Karimi, Farrokh; Mesbahfar, Majid; Samadi, Naser; Hejazi, Mohammad Saeid

    2012-12-15

    Oxidative stress occurs as a result of imbalance between generation and detoxification of reactive oxygen species (ROS). This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Relation between cytoplasmic recombinant protein expression with H(2)O(2) concentration and catalase activity variation was already reported. The periplasmic space of E. coli has different oxidative environment in relative to cytoplasm and there are some benefits in periplasmic expression of recombinant proteins. In this study, hydrogen peroxide concentration and catalase activity following periplasmic expression of mouse IL-4 were measured in E. coli. After construction of pET2mIL4 plasmid, the expression of recombinant mouse interleukin-4 (mIL-4) was confirmed. Then, the H(2)O(2) concentration and catalase activity variation in the cells were studied in exponential and stationary phases at various ODs and were compared to those of wild type cells and empty vector transformed cells. It was revealed that empty vector introduction and periplasmic recombinant protein expression increased significantly the H(2)O(2) concentration of the cells. However, the H(2)O(2) concentration in mIL-4 expressing cells was significantly higher than its concentration in empty vector transformed cells, demonstrating more effects of recombinant mIL-4 expression on H(2)O(2) elevation. Likewise, although catalase activity was reduced in foreign DNA introduced cells, it was more lowered following expression of recombinant proteins. Correlation between H(2)O(2) concentration elevation and catalase activity reduction with cell growth depletion is also demonstrated. It was also found that recombinant protein expression results in cell size increase.

  20. Short-term 222Rn activity concentration changes in underground spaces with limited air exchange with the atmosphere

    NASA Astrophysics Data System (ADS)

    Fijałkowska-Lichwa, L.; Przylibski, T. A.

    2011-04-01

    The authors investigated short-time changes in 222Rn activity concentration occurring yearly in two underground tourist facilities with limited air exchange with the atmosphere. One of them is Niedźwiedzia (Bear) Cave in Kletno, Poland - a natural space equipped with locks ensuring isolation from the atmosphere. The other site is Fluorite Adit in Kletno, a section of a disused uranium mine. This adit is equipped with a mechanical ventilation system, operated periodically outside the opening times (at night). Both sites are situated within the same metamorphic rock complex, at similar altitudes, about 2 km apart. The measurements conducted revealed spring and autumn occurrence of convective air movements. In Bear Cave, this process causes a reduction in 222Rn activity concentration in the daytime, i.e. when tourists, guides and other staff are present in the cave. From the point of view of radiation protection, this is the best situation. For the rest of the year, daily concentrations of 222Rn activity in the cave are very stable. In Fluorite Adit, on the other hand, significant variations in daily 222Rn activity concentrations are recorded almost all year round. These changes are determined by the periods of activity and inactivity of mechanical ventilation. Unfortunately this is inactive in the daytime, which results in the highest values of 222Rn activity concentration at the times when tourists and staff are present in the adit. Slightly lower concentrations of radon in Fluorite Adit are recorded in the winter season, when convective air movements carry a substantial amount of radon out into the atmosphere. The incorrect usage of mechanical ventilation in Fluorite Adit results in the most unfavourable conditions in terms of radiation protection. The staff working in that facility are exposed practically throughout the year to the highest 222Rn activity concentrations, both at work (in the adit) and at home (outside their working hours). Therefore, not very well

  1. Comparison of peak characteristics of the F2 ionospheric layer obtained from the Cyprus Digisonde and IRI-2012 model during low and high solar activity period

    NASA Astrophysics Data System (ADS)

    Haralambous, Haris; Oikonomou, Christina

    2015-11-01

    We investigate first the climatology expressed by diurnal and seasonal variations of the critical frequency (foF2) and the peak height (hmF2) of the F2-layer derived from digital ionosonde measurements at the low-middle latitude European station in Nicosia, Cyprus (geographical coordinates: 35°N, 33°E, geomagnetic lat. 29.38°N, I = 51.7°). Monthly median hourly values of the F2-layer peak characteristics are obtained using manually scaled data during the 5-year period 2009-2013. The observational results are then compared with the International Reference Ionospheric Model (IRI-2012) predictions using both URSI and CCIR coefficients. It is shown that the semi-annual pattern of daytime foF2 characterized by higher values at equinoxes than either solstices as well as the winter anomaly phenomenon demonstrate strong solar activity dependence. An annual pattern of night-time foF2 is also detected with lower values in winter and higher in summer. The seasonal variation of daytime hmF2 is evident and peaks of hmF2 at pre-sunrise and post-sunset hours are identified during December. The IRI-2012 model is capable to capture the main diurnal and seasonal patterns of foF2 and hmF2. The highest overestimation of daytime foF2 is noted at equinoxes and solstices except from March, October, December of 2011, and June of 2013. Significant foF2 underestimation is observed at evening and after midnight during February and March of 2009. Large positive discrepancies between the modeled and observed hmF2 values are noticed during the deep solar minimum year 2009. Overall, IRI-model estimates are more accurate for hmF2 than foF2 over Cyprus and for the examined period.

  2. Pharmacokinetics of human activated protein C. 1st communication: plasma concentration and excretion of a lyophilized purified human activated protein C after intravenous administration in the mouse and the rabbit.

    PubMed

    Ishii, S; Mochizuki, T; Nagao, T; Sugiki, S; Kudo, S; Harakawa, N; Taniguchi, K; Igarashi, Y; Kondo, S; Kiyoki, M

    1995-05-01

    Pharmacokinetic studies of human activated protein C (CAS 42617-41-4, APC) were investigated in mice and rabbits with 125I-labeled compound. Plasma levels of APC were determined by three different assays: total radioactivity, APC antigenicity determined by sandwich enzyme-linked immunosorbent assay (ELISA), and the amidolytic activity which was performed by immunologically captured APC. APC concentration obtained from these assays were shown to be correlated well at early times post-dose. After intravenous administration, total radioactivity in the plasma declined tri-exponentially, but antigenicity and amidolytic activity in the plasma declined biexponentially. Plasma AUC increased proportionally with the dose, and the total body clearance and t1/2 did not change significantly. In addition, no significant difference was observed between the pharmacokinetics in male and female mice. In rabbit study, the profiles of times vs APC concentration in the plasma was similar to those in mice after single bolus injection. The plasma concentrations of APC during and after infusion in rabbits were also determined. APC concentration increased during infusion and reached almost steady state at the end of infusion. The profiles of the APC concentration in benzamidine citrate plasma corresponded to the simulated curves which were characterized by the parameters obtained from the single bolus experiment. Plasma disposition profiles of the protein were studied with high performance gel chromatography method. The radioactivity in the unchanged APC was observed at 15 min after administration. At 1 h, most of the radioactivity was observed in larger molecule fraction than the intact APC. These results corresponded to the decrease of amidolytic activity in the plasma.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7612068

  3. Application of acid-activated Bauxsol for wastewater treatment with high phosphate concentration: Characterization, adsorption optimization, and desorption behaviors.

    PubMed

    Ye, Jie; Cong, Xiangna; Zhang, Panyue; Zeng, Guangming; Hoffmann, Erhard; Liu, Yang; Wu, Yan; Zhang, Haibo; Fang, Wei; Hahn, Hermann H

    2016-02-01

    Acid-activated Bauxsol was applied to treat wastewater with high phosphate concentration in a batch adsorption system in this paper. The effect of acid activation on the change of Bauxsol structure was systematically investigated. The mineralogical inhomogeneity and intensity of Bauxsol decreased after acid activation, and FeCl3·2H2O and Al(OH)3 became the dominant phases of acid-activated Bauxsol adsorption. Moreover, the BET surface area and total pore volume of Bauxsol increased after acid activation. Interaction of initial solution pH and adsorption temperature on phosphate adsorption onto acid-activated Bauxsol was investigated by using response surface methodology with central composite design. The maximum phosphate adsorption capacity of 192.94 mg g(-1) was achieved with an initial solution pH of 4.19 and an adsorption temperature of 52.18 °C, which increased by 7.61 times compared with that of Bauxsol (22.40 mg g(-1)), and was higher than other adsorbents. Furthermore, the desorption studies demonstrated that the acid-activated Bauxsol was successfully regenerated with 0.5 mol L(-1) HCl solution. The adsorption capacity and desorption efficiency of acid-activated Bauxsol maintained at 80.48% and 93.02% in the fifth adsorption-desorption cycle, respectively, suggesting that the acid-activated Bauxsol could be repeatedly used in wastewater treatment with high phosphate concentration. PMID:26606195

  4. Application of acid-activated Bauxsol for wastewater treatment with high phosphate concentration: Characterization, adsorption optimization, and desorption behaviors.

    PubMed

    Ye, Jie; Cong, Xiangna; Zhang, Panyue; Zeng, Guangming; Hoffmann, Erhard; Liu, Yang; Wu, Yan; Zhang, Haibo; Fang, Wei; Hahn, Hermann H

    2016-02-01

    Acid-activated Bauxsol was applied to treat wastewater with high phosphate concentration in a batch adsorption system in this paper. The effect of acid activation on the change of Bauxsol structure was systematically investigated. The mineralogical inhomogeneity and intensity of Bauxsol decreased after acid activation, and FeCl3·2H2O and Al(OH)3 became the dominant phases of acid-activated Bauxsol adsorption. Moreover, the BET surface area and total pore volume of Bauxsol increased after acid activation. Interaction of initial solution pH and adsorption temperature on phosphate adsorption onto acid-activated Bauxsol was investigated by using response surface methodology with central composite design. The maximum phosphate adsorption capacity of 192.94 mg g(-1) was achieved with an initial solution pH of 4.19 and an adsorption temperature of 52.18 °C, which increased by 7.61 times compared with that of Bauxsol (22.40 mg g(-1)), and was higher than other adsorbents. Furthermore, the desorption studies demonstrated that the acid-activated Bauxsol was successfully regenerated with 0.5 mol L(-1) HCl solution. The adsorption capacity and desorption efficiency of acid-activated Bauxsol maintained at 80.48% and 93.02% in the fifth adsorption-desorption cycle, respectively, suggesting that the acid-activated Bauxsol could be repeatedly used in wastewater treatment with high phosphate concentration.

  5. Dynamics of lingual antimicrobial peptide, lactoferrin concentrations and lactoperoxidase activity in the milk of cows treated for clinical mastitis.

    PubMed

    Kawai, Kazuhiro; Korematsu, Kiyoshi; Akiyama, Kiyoshi; Okita, Miki; Yoshimura, Yukinori; Isobe, Naoki

    2015-02-01

    The aim of the present study was to examine changes in innate immune factors in the milk of mastitic dairy cows treated with antibiotics. Cows in the antibiotics group (n = 13) were infused into the mammary gland with cefazolin on the sixth day after mastitis was diagnosed (the day of the mastitis diagnosis = day -6). The control group (n = 12) was not treated. Milk samples were collected once every 2 days from days -6 to 12 and somatic cell count (SCC), lingual antimicrobial peptide (LAP), and lactoferrin (LF) concentrations and lactoperoxidase (LPO) activity were measured. SCC and LF concentrations in the antibiotics group markedly decreased after the antibiotic treatment. When cows in the antibiotics group were divided according to SCC on day 0, LAP concentrations and LPO activity in cows with a lower SCC on day 0 (<5 × 10(6) cell/mL) were significantly higher and lower than those in cows with a higher SCC, respectively. These results suggest that LF concentration decreased with decrease in SCC after treatment and that LAP concentration and LPO activity differed depending on the severity of mastitis. This is the first report to reveal the dynamics of innate immune factor in milk of cows treated for clinical mastitis.

  6. Nanoscale Concentration Quantification of Pharmaceutical Actives in Amorphous Polymer Matrices by Electron Energy-Loss Spectroscopy.

    PubMed

    Ricarte, Ralm G; Lodge, Timothy P; Hillmyer, Marc A

    2016-07-26

    We demonstrated the use of electron energy-loss spectroscopy (EELS) to evaluate the composition of phenytoin:hydroxypropyl methylcellulose acetate succinate (HPMCAS) spin-coated solid dispersions (SDs). To overcome the inability of bright-field and high-angle annular dark-field TEM imaging to distinguish between glassy drug and polymer, we used the π-π* transition peak in the EELS spectrum to detect phenytoin within the HPMCAS matrix of the SD. The concentration of phenytoin within SDs of 10, 25, and 50 wt % drug loading was quantified by a multiple least-squares analysis. Evaluating the concentration of 50 different regions in each SD, we determined that phenytoin and HPMCAS are intimately mixed at a length scale of 200 nm, even for drug loadings up to 50 wt %. At length scales below 100 nm, the variance of the measured phenytoin concentration increases; we speculate that this increase is due to statistical fluctuations in local concentration and chemical changes induced by electron irradiation. We also performed EELS analysis of an annealed 25 wt % phenytoin SD and showed that the technique can resolve concentration differences between regions that are less than 50 nm apart. Our findings indicate that EELS is a useful tool for quantifying, with high accuracy and sub-100 nm spatial resolution, the composition of many pharmaceutical and soft matter systems. PMID:27419264

  7. Antibacterial activities of persimmon extracts relate with their hydrogen peroxide concentration.

    PubMed

    Arakawa, Hidetoshi; Takasaki, Makiko; Tajima, Noriko; Fukamachi, Haruka; Igarashi, Takeshi

    2014-01-01

    Persimmon, a deciduous tree of the family Ebenaceae, is found throughout East Asia and contains high levels of tannins. This class of natural compounds exhibit favorable toxicity profiles along with bactericidal activity without the emergence of resistant bacteria, suggesting potential medical applications. Consistent with these observations, persimmon leaves show antibacterial activity. However, the mechanism of persimmon antibacterial activity remains unknown. In the present work, we demonstrate that the antibacterial activity of persimmon reflects the generation of reactive oxygen from tannins. The identification and quantification of reactive oxygen generated from persimmon and the level of antibacterial activity were determined.

  8. Effect of nano-zinc oxide on nitrogenase activity in legumes: an interplay of concentration and exposure time

    NASA Astrophysics Data System (ADS)

    Kumar, Praveen; Burman, Uday; Santra, P.

    2015-07-01

    Experiments were carried out to study the effect of zinc oxide nanoparticles (nano-ZnO) on nitrogenase activity in legumes. In the first experiment, nodulated roots of cluster bean, moth bean, green gram and cowpea were dipped in Hoagland solution containing 1.5 and 10 μg mL-1 of nano-ZnO for 24 h. Nitrogenase activity in cluster bean, green gram and cowpea roots increased after dipping in solution containing 1.5 μg mL-1 nano-ZnO, but decreased in roots dipped in solution containing 10 μg mL-1 nano-ZnO. However, in moth bean roots, nitrogenase activity decreased after dipping in solution containing either concentration of nano-ZnO. In the second experiment, nodulated roots of green gram were dipped in Hoagland solution containing 1, 4, 6, 8 and 10 μg mL-1 nano-ZnO for 6-30 h before estimating nitrogenase activity. Results showed that an interactive effect of nano-ZnO concentration and exposure time influenced nitrogenase activity. The possible reasons behind this effect have been discussed. A model [ A = 3.44 + 0.46 t - 0.01 t 2 - 0.002 tc 2 ( R 2 = 0.81)] involving linear and power components was developed to simulate the response of nitrogenase activity in green gram roots to the concentration and exposure time of nano-ZnO.

  9. Effect of chloroethene concentrations and granular activated carbon on reductive dechlorination rates and growth of Dehalococcoides spp.

    PubMed

    Aktaş, Özgür; Schmidt, Kathrin R; Mungenast, Sarah; Stoll, Claudia; Tiehm, Andreas

    2012-01-01

    This study focused on the investigation of (i) the tetrachloroethene (PCE) toxicity threshold of a reductively dechlorinating mixed culture containing Dehalococcoides spp., (ii) the adsorption of PCE on different types of granular activated carbon (GAC), and (iii) the bioavailability and reductive dechlorination in the presence of GAC. The abundance of Dehalococcoides spp. detected by quantitative real-time polymerase chain reaction (qPCR) was found to increase by 2-4 orders of magnitude during degradation of PCE. No degradation occurred at dissolved concentrations beyond 420 μM (70 mg/L). Different adsorption isotherms were determined for thermally and chemically activated carbons. The addition of GAC to biological assays reduced the dissolved PCE concentration below the toxicity threshold. The combination of microbial reductive dechlorination with GAC adsorption proved to be a promising method for remediation of groundwater contaminated by high concentrations of chloroethenes.

  10. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant

    PubMed Central

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-01-01

    The radioactive fission product 90Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing 90Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure 90Sr activity concentration using liquid scintillation counting. 137Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with 90Sr. The 90Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg−1 while the 137Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg−1. The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of 134Cs. However, 90Sr contamination was not confirmed in all samples although detectable amounts of 90Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between 90Sr and 137Cs activity concentrations provides a potentially powerful tool to discriminate background 90Sr level from its Fukushima contribution. PMID:27048779

  11. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant

    NASA Astrophysics Data System (ADS)

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-04-01

    The radioactive fission product 90Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing 90Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure 90Sr activity concentration using liquid scintillation counting. 137Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with 90Sr. The 90Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg‑1 while the 137Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg‑1. The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of 134Cs. However, 90Sr contamination was not confirmed in all samples although detectable amounts of 90Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between 90Sr and 137Cs activity concentrations provides a potentially powerful tool to discriminate background 90Sr level from its Fukushima contribution.

  12. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant.

    PubMed

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-01-01

    The radioactive fission product (90)Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing (90)Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure (90)Sr activity concentration using liquid scintillation counting. (137)Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with (90)Sr. The (90)Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg(-1) while the (137)Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg(-1). The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of (134)Cs. However, (90)Sr contamination was not confirmed in all samples although detectable amounts of (90)Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between (90)Sr and (137)Cs activity concentrations provides a potentially powerful tool to discriminate background (90)Sr level from its Fukushima contribution. PMID:27048779

  13. Strontium-90 activity concentration in soil samples from the exclusion zone of the Fukushima daiichi nuclear power plant.

    PubMed

    Sahoo, Sarata Kumar; Kavasi, Norbert; Sorimachi, Atsuyuki; Arae, Hideki; Tokonami, Shinji; Mietelski, Jerzy Wojciech; Łokas, Edyta; Yoshida, Satoshi

    2016-04-06

    The radioactive fission product (90)Sr has a long biological half-life (˜18 y) in the human body. Due to its chemical similarity to calcium it accumulates in bones and irradiates the bone marrow, causing its high radio-toxicity. Assessing (90)Sr is therefore extremely important in case of a nuclear disaster. In this work 16 soil samples were collected from the exclusion zone (<30 km) of the earthquake-damaged Fukushima Daiichi nuclear power plant, to measure (90)Sr activity concentration using liquid scintillation counting. (137)Cs activity concentration was also measured with gamma-spectroscopy in order to investigate correlation with (90)Sr. The (90)Sr activity concentrations ranged from 3.0 ± 0.3 to 23.3 ± 1.5 Bq kg(-1) while the (137)Cs from 0.7 ± 0.1 to 110.8 ± 0.3 kBq kg(-1). The fact that radioactive contamination originated from the Fukushima nuclear accident was obvious due to the presence of (134)Cs. However, (90)Sr contamination was not confirmed in all samples although detectable amounts of (90)Sr can be expected in Japanese soils, as a background, stemming from global fallout due to the atmospheric nuclear weapon tests. Correlation analysis between (90)Sr and (137)Cs activity concentrations provides a potentially powerful tool to discriminate background (90)Sr level from its Fukushima contribution.

  14. Enhancing The USDA Global Crop Assessment Decision Support System Using Satellite-Based Soil Moisture Estimates Obtained From The Soil Moisture Active Passive Mission

    NASA Astrophysics Data System (ADS)

    Mladenova, I. E.; Bolten, J. D.; Crow, W. T.; Reynolds, C. A.

    2015-12-01

    The primary goal of the U.S. Department of Agriculture Foreign Agricultural Service (FAS) is to provide timely information on current and expected crop supply and demand estimates. Inter-annual variability in crop condition and crop productivity is largely controlled by the amount of available water to the plants. Thus, knowledge of the root-zone soil moisture is critical for the USDA's crop analysts. This information is currently provided by the modified Palmer model (PM). The PM is a two-layer, water balance-based hydrologic model that is driven by daily precipitation and daily minimum and maximum temperature observations based on ground meteorological station measurements from the World Meteorological Organization (WMO) and gridded weather data from the U.S. Air Force 557th Weather Wing (former U.S. Air Force Agency, AFWA). A data assimilation (DA) unit was added to the model to allow the integration of satellite-based soil moisture observations. The DA system was initially developed using retrievals from the Advanced Microwave Scanning Radiometer (AMSR-E), where the AMSR-E soil moisture estimates were ingested into the PM using a 1-D Ensemble Kalman Filter Approach. After the failure of AMSR-E the system was updated and it is currently set to ingest Soil Moisture Ocean Salinity (SMOS)-based retrievals. Operational delivery of the SMOS-based soil moisture product for USDA FAS began in spring, 2014. This talk will demonstrate the added value of assimilating satellite-based data and focus on work that is being done in preparation for updating the system by ingesting soil moisture observations from the Soil Moisture Active Passive (SMAP) mission. Soil moisture estimates derived using data obtained from SMOS and the Advanced Scatterometer (ASCAT) instrument on MetOp have been used as a proxy for the SMAP radiometer and radar products, respectively. The performance of this dual assimilation system would be assessed by examining the lagged rank cross correlation

  15. Relative reactivity of ribosyl 2'-OH vs. 3'-OH in concentrated aqueous solutions of phosphoimidazolide activated nucleotides

    NASA Technical Reports Server (NTRS)

    Kanavarioti, A.; Lee, L. F.; Gangopadhyay, S.

    1999-01-01

    Phosphoimidazolide activated ribomononucleotides (*pN, see structure) are useful substrates for the non-enzymatic synthesis of oligonucleotides. In the presence of metal ions, aqueous solutions of *pN yield primarily the two internucleotide-linked (pN2' pN and pN3' pN) and the pyrophosphate-linked (N5' ppN) dimers. Small amounts of cyclic dimers and higher oligomers are also produced. In this study the relative reactivity of 2'-OH vs. 3'-OH was determined from the ratio of the yields of pN2' pN vs. pN3' pN. Experiments were performed at 23 degrees C in the range 7.2 < or = pH < or = 8.4 with substrates that differ in nucleobase (guanosine (G), cytidine (C), uridine (U), and adenosine (A)) and leaving group (imidazole (Im), 2-methylimidazole (2-MeIm) and 2,4-dimethylimidazole (2,4-diMeIm)). Two metal ions (Mg2+ or Mn2+) were employed as catalysts. The conditions used here, i.e. a substrate concentration in the range 0.1 M to 1.0 M and metal ion concentration in the range 0.05 M to 0.2 M, favor base-stacking interactions. The ratio pN2' pN: pN3' pN = 2'-5': 3'-5' was found independent of nucleobase and typically varied between 2 to 3 indicating that the 2'-OH is about 2 to 3 times more reactive than the 3'-OH. *pN with Im, compared to 2-MeIm and 2,4-diMeIm leaving group, produce lower yields of internucleotide linked dimers, and a higher pN2' pN: pN3' pN ratio. Trends in the data, observed with all three leaving groups, suggest an increase in pN2' pN: pN3' pN ratio with decreasing substrate concentration (up to 5.47 with 0.051 M ImpG). The observations are in accord with earlier studies reporting a relative reactivity 2'-5': 3'-5' = 6 to 9 obtained with Im as the leaving group, in dilute nucleotide solutions and under conditions that disfavor stacking. It is speculated that the concentration induced change in the relative reactivity is the result of self-association via base-stacking that enhances selectively the proximity of the 3'-OH of one molecule to the reactive

  16. Plasma sex steroid concentrations and gonadal aromatase activities in African clawed frogs (Xenopus laevis) from South Africa.

    PubMed

    Hecker, Markus; Giesy, John P; Jones, Paul D; Jooste, Alarik M; Carr, James A; Solomon, Keith R; Smith, Ernest E; Van der Kraak, Glen; Kendall, Ronald J; Du Preez, Louis

    2004-08-01

    Adult African clawed frogs (Xenopus laevis) were collected from a corn-growing region (CGR) and a non-corn-growing region (NCGR) with different exposure profiles for atrazine and related triazines. Physical, chemical, and biological parameters from the catchment areas were also measured. Frogs were surveyed for possible effects of exposure to triazine herbicides on plasma testosterone (T) and estradiol (E2) titers, gonadal aromatase activity, and gonad growth (GSI). Concentrations of both T and E2 varied among locations and were correlated to some accessory factors, such as pH, several ions, and metals. Greatest median plasma T concentrations (males: 19 ng/ml; females: 16 ng/ml) occurred in frogs inhabiting NCGR as compared to those from the CGR (males: 4 ng/ml; females: 1 ng/ml). Median E2 concentrations were also greater in frogs collected from the NCGR (males: 3 ng/ml; females: 28 ng/ml) than those in frogs from the CGR (males: 2 ng/ml; females: 5 ng/ml). Because some exposure to agricultural chemicals at both regions occurred, as did simultaneous exposures to multiple chemicals, a regression analysis was employed. Negative correlations were observed between plasma T concentrations and concentrations of atrazine, deisopropylatrazine, deethylatrazine, and tertbuthylazine in females and between T and diaminochlorotriazine in males. Estradiol in females exhibited a significant negative correlation with atrazine and deethylatrazine. No correlations were observed between gonadal aromatase activity or GSI and any of the agricultural chemicals measured. Median aromatase activities in ovaries varied among sampling sites ranging from 7 to >3000 times greater than those in males when measurable. Testicular aromatase activity was below the detection limit of the assay in male frogs at most of the sites. Although exposure to agricultural inputs did not affect aromatase activities, effects of atrazine or coapplied pesticides on sex steroid homeostasis cannot be excluded at

  17. Tritium activity concentrations and residence times of groundwater collected in Rokkasho, Japan.

    PubMed

    Hasegawa, Hidenao; Ueda, Shinji; Akata, Naofumi; Kakiuchi, Hideki; Hisamatsu, Shun'ichi

    2015-11-01

    Tritium ((3)H) concentrations were measured in groundwater samples from four surface wells (4-10 m deep), four shallow wells (24-26.5 m deep) and a 150-m-deep well in the Futamata River catchment area, which is adjacent to the large-scale commercial spent nuclear fuel reprocessing plant in Rokkasho, Japan. The (3)H concentrations in most of the surface- and shallow-well samples (<0.03-0.57 Bq l(-1)) were similar to those in precipitation (annual mean: 0.31-0.79 Bq l(-1)), suggesting that the residence time of the water in those wells was 0-15 y. The (3)H concentrations in the samples from a 26-m-deep well and the 150-m-deep well were lower than those in the other wells, indicating that groundwater with a long residence time exists in deep aquifers and the estuary area of the catchment. It is not clear whether (3)H released during test operation of the plant with actual spent nuclear fuel affected the (3)H concentrations observed in this study.

  18. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during two consecutive fiscal years. (b) A CDC's 504 loan portfolio must be diversified by business sector....

  19. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during two consecutive fiscal years. (b) A CDC's 504 loan portfolio must be diversified by business sector....

  20. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during two consecutive fiscal years. (b) A CDC's 504 loan portfolio must be diversified by business sector....

  1. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during two consecutive fiscal years. (b) A CDC's 504 loan portfolio must be diversified by business sector....

  2. 13 CFR 120.828 - Minimum level of 504 loan activity and restrictions on portfolio concentrations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Requirements for Cdc... concentrations. (a) A CDC is required to receive SBA approval of at least four 504 loan approvals during two consecutive fiscal years. (b) A CDC's 504 loan portfolio must be diversified by business sector....

  3. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration.

    PubMed

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO(2) concentration is currently (2012) 393.1 μmol mol(-1), an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO(2) concentrations, an experiment was conducted using the Free Air CO(2) Enrichment (FACE )system. Two conventional japonica rice varieties (Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO(2) on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO(2) levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO(2) concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO(2) concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO(2) concentration increased enzyme activity expression and starch synthesis, affecting the

  4. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration

    NASA Astrophysics Data System (ADS)

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO2 concentration is currently (2012) 393.1 μmol mol-1, an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO2 concentrations, an experiment was conducted using the Free Air CO2 Enrichment (FACE )system. Two conventional japonica rice varieties ( Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO2 on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO2 levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO2 concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO2 concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO2 concentration increased enzyme activity expression and starch synthesis, affecting the final contents

  5. Effect of diet of varying protein concentrations on the activity of erythrocyte membrane Ca2+Mg2+ ATPase in dogs.

    PubMed

    Adewoye, E O; Ige, A O; Adeyanju, O; Bekibele, E B

    2010-11-25

    Alterations in protein diet have been reported to result in alterations in calcium homeostasis in the body. Ca2+Mg2+ATPase is an ubiquitous enzyme important in calcium homeostasis in the body. The effect of varying protein diet on the activities of Ca2+ pump across cell membranes is however yet to be fully elucidated. In this study, the activity of erythrocyte membrane calcium pump in response to varying protein concentration in diet was therefore studied in the dog. The study was carried out in 24 dogs, randomly divided into 4 groups. The groups were fed with diets containing 30%, 26%, 16% and 0% proteins (high, medium, low and zero) for six weeks respectively. Blood samples were collected from each animal to determine packed cell volumes, hematocrit, blood urea, electrolyte studies and erythrocyte ghost membrane studies. The effects of Ca2+ and ATP on the activity of Ca2+Mg2+ ATPase were determined in the isolated ghost membrane. The result of the study shows that there was a protein diet dependent increase in the activity of Ca2+Mg2+ ATPase in the presence and absence of ATP in all the groups with the highest activity recorded in the high protein diet group and the lowest activity observed in the zero protein group. There was also a protein diet dependent increase in the protein concentration of the membranes in all groups observed with the highest protein concentration recorded in the high protein diet group and the lowest activity observed in the zero protein group. There was a significant decrease in K+ concentration (P <0.05) and a significant increase in urea concentration of animals fed with high protein diet (P <0.05). There was also a significant increase (P <0.05) in HCO3- concentration in the animals fed with medium protein diet and no significant difference in the PCV and heamatocrit values in all groups. This study has shown that high protein diets increase the activity of the Ca2+Mg2+ ATPase in the presence and absence of ATP.

  6. More efficient reversal of dabigatran inhibition of coagulation by activated prothrombin complex concentrate or recombinant factor VIIa than by four-factor prothrombin complex concentrate.

    PubMed

    Lindahl, Tomas L; Wallstedt, Maria; Gustafsson, Kerstin M; Persson, Egon; Hillarp, Andreas

    2015-03-01

    The number of patients on antithrombotic treatment due to atrial fibrillation and venous thromboembolism is increasing fast due to an aging population. A growing proportion will be treated with novel oral anticoagulants, the first in clinical use was the direct oral thrombin inhibitor dabigatran (Pradaxa®). A small percentage of the patients on dabigatran will experience serious bleeding or be in need of urgent surgery. The aim of this study was to test the effects of different hemostatic agents in potentially reversing the anticoagulant effects in vitro in blood or platelet-rich plasma (PRP) spiked with dabigatran. Whole blood or PRP was spiked with the active substance dabigatran, 200 μg/L. We measured clotting time being induced by 1.4 pmol/L tissue factor using the instrument ReoRox2™ and initial clot growth velocity from a tissue factor covered surface using the instrument Thrombodynamics Analyzer T-2™. Dabigatran prolonged clotting time 5-fold but reduced clot growth velocity only slightly. The reversing effects of prothrombin complex concentrates (PCC), activated PCC (APCC) and recombinant activated factor VII (rFVIIa) were then tested. APCC (1.8 U/mL) reduced the prolonged clotting time by 1/3, rFVIIa (2 μg/L) only slightly (n = 10-20). The reduction was not significant using Mann-Whitney test but significant using t-test with Bonferronis' correction for multiple comparisons, whereas PCC (0.56 U/mL) had no effect on clotting time. APCC doubled initial clot growth velocity, although even more in the absence of dabigatran. In conclusion, APCC and rFVIIa, but not PCC, seem to reverse, at least partially, some effects of dabigatran on coagulation parameters. Systematic evaluation of case reports, registries and, ultimately, randomized clinical trials are needed to elucidate potential benefit for patients.

  7. Relation between dabigatran concentration, as assessed using the direct thrombin inhibitor assay, and activated clotting time/activated partial thromboplastin time in patients with atrial fibrillation.

    PubMed

    Okubo, Kenji; Kuwahara, Taishi; Takagi, Katsumasa; Takigawa, Masateru; Nakajima, Jun; Watari, Yuji; Nakashima, Emiko; Yamao, Kazuya; Fujino, Tadashi; Tsutsui, Hiroyuki; Takahashi, Atsushi

    2015-06-15

    Dabigatran is a direct thrombin inhibitor that has been approved for preventing stroke in patients with atrial fibrillation. In this study, we aimed to assess the associations between the dabigatran concentration (calculated through plasma-diluted thrombin time, as assessed using the Hemoclot assay) and the activated partial thromboplastin time (aPTT) and activated clotting time (ACT). We recruited 137 patients with atrial fibrillation who were receiving a normal dose of dabigatran (300 mg/d) or a reduced dose of dabigatran (220 mg/d, usually administered to patients who were elderly, had moderate renal dysfunction, or who were also receiving verapamil). We then assessed the aPTT, ACT, and Hemoclot results of the patients and calculated the plasma dabigatran concentration. The mean plasma concentration of dabigatran was 127 ± 88 ng/ml, although no significant differences in dabigatran concentration, ACT, or aPTT were observed when we compared the 2 doses of dabigatran (300 or 220 mg/d). The dabigatran concentration was within the therapeutic levels in most patients, although a high value (>300 ng/ml) was observed in several patients, which indicated a high risk of bleeding. The dabigatran concentration was strongly and positively correlated with ACT and aPTT (r = 0.87, p <0.001; and r = 0.76, p <0.001; respectively). Multivariate analysis revealed that verapamil use was independently associated with elevated dabigatran concentrations (p <0.001). Therefore, ACT and aPTT may be useful for bedside assessment of the anticoagulant activity of dabigatran, and verapamil use may be a risk factor for elevated dabigatran concentrations.

  8. EROD activity and genotoxicity in the seabob shrimp Xiphopenaeus kroyeri exposed to benzo[a]pyrene (BaP) concentrations.

    PubMed

    da Silva Rocha, Arthur José; Gomes, Vicente; Rocha Passos, Maria José de Arruda Campos; Hasue, Fabio Matsu; Alves Santos, Thaís Cruz; Bícego, Márcia Caruso; Taniguchi, Satie; Van Ngan, Phan

    2012-11-01

    Seabob shrimp Xiphopenaeus kroyeri is a marine species that lives in shallow waters of coastal environments, often impacted by polycyclic aromatic hydrocarbons (PAH) pollution. In the present study, seabob shrimp were exposed for 96 h to benzo[a]pyrene (BaP) at the nominal concentrations of 100, 200, 400 and 800 microg-L(-1). Animals of the control groups were exposed either to clean water or to the BaP-carrier (DMSO). At the end of the exposures, muscle tissues were sampled for BaP uptake assessment and hepatopancreas and hemolymph for EROD enzyme activity and hemocytes DNA damage, respectively. EROD activity and DNA damage increased significantly as a function of BaP exposure concentrations. Significant correlations between BaP uptake and both EROD activity and DNA damage suggest that they can be used as suitable tools for integrated levels of study on the biomarkers of PAH exposure.

  9. Effective photodegradation of methomyl pesticide in concentrated solutions by novel enhancement of the photocatalytic activity of TiO2 using CdSO4 nanoparticles.

    PubMed

    Barakat, N A M; Nassar, M M; Farrag, T E; Mahmoud, M S

    2014-01-01

    Annihilation of electrons-holes recombination process is the main remedy to enhance the photocatalytic activity of the semiconductors photocatalysts. Doping of this class of photocatalysts by foreign nanoparticles is usually utilized to create high Schottky barrier that facilitates electron capture. In the literature, because nonpolar nanoparticles (usually pristine metals, e.g., Ag, Pt, Au, etc.) were utilized in the doping process, the corresponding improvement was relatively low. In this study, CdSO4-doped TiO2 nanoparticles are introduced as a powerful and reusable photocatalyst for the photocatalytic degradation of methomyl pesticide in concentrated aqueous solutions. The utilized CdSO4 nanoparticles form polar grains in the TiO2 matrix due to the electrons leaving characteristic of the sulfate anion. The introduced nanoparticles could successfully eliminate the harmful pesticide under the sunlight radiation within a very short time (less than 1 h), with a removal capacity reaching 1,000 mg pesticide per gram of the introduced photocatalyst. Moreover, increase in the initial concentration of the methomyl did not affect the photocatalytic performance; typically 300, 500, 1,000, and 2,000 mg/l solutions were completely treated within 30, 30, 40, and 60 min, respectively, using 100 mg catalyst. Interestingly, the photocatalytic efficiency was not affected upon multiple use of the photocatalyst. Moreover, negative activation energy was obtained which reveals super activity of the introduced photocatalyst. The distinct photocatalytic activity indicates the complete annihilation of the electrons-holes recombination process and abundant existence of electrons on the catalyst surfaces due to strong electrons capturing the operation of the utilized polar CdSO4 nanoparticles. The introduced photocatalyst has been prepared using the sol-gel technique. Overall, the simplicity of the synthesizing procedure and the obtained featured photocatalytic activity strongly

  10. Coupling of total hemoglobin concentration, oxygenation, and neural activity in rat somatosensory cortex.

    PubMed

    Devor, Anna; Dunn, Andrew K; Andermann, Mark L; Ulbert, Istvan; Boas, David A; Dale, Anders M

    2003-07-17

    Recent advances in brain imaging techniques, including functional magnetic resonance imaging (fMRI), offer great promise for noninvasive mapping of brain function. However, th