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Sample records for acid enhanced electrodialytic

  1. Organic acid enhanced electrodialytic extraction of lead from contaminated soil fines in suspension

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ahring, Birgitte Kiær; Ottosen, Lisbeth M.

    2007-01-01

    The implementation of soil washing technology for the treatment of heavy metal contaminated soils is limited by the toxicity and unwieldiness of the remaining heavy metal contaminated sludge. In this work, the feasibility of combining electrodialytic remediation with heterotrophic leaching...... for decontamination of the sludge was investigated. The ability of 11 organic acids to extract Pb from the fine fraction of contaminated soil (grains ... was tested. Five of the acids showed the ability to extract Ph from the soil fines in excess of the effect caused solely by pH changes. Addition of the acids, however, severely impeded EDR, hence promotion of EDR by combination with heterotrophic leaching was rejected. In contrast, enhancement of EDR...

  2. ELECTRODIALYTIC PRODUCTION OF HYPOPHOSPHOROUS ACID

    Institute of Scientific and Technical Information of China (English)

    CHENG Jianzhong; ZHANG Yingzhe; ZHANG Baogui; ZHANG Zhengpu

    2001-01-01

    Disclosed is a method of preparing hypophosphorous acid comprising contacting an insoluble anode with an aqueous solution of hypophosphite anions and applying a direct current through the insoluble anode to a cathode in electrical contact with the aqueous solution to generate H+ ions in the aqueous solution thereby forming a hypophosphorous acid solution. The process is simple,low cost and high efficient, which can be tied into an existing process for producing sodium hypophosphite wherein the product of sodium hypophosphite process is used as a starting material in the hypophosphorous acid process.

  3. Pulse current enhanced electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Sun, Tian R.; Ottosen, Lisbeth M.; Jensen, Pernille E.

    2012-01-01

    Energy consumption is an important factor influencing the cost of electrodialytic soil remediation (EDR). It has been indicated that the pulse current (in low frequency range) could decrease the energy consumption during EDR. This work is focused on the comparison of energy saving effect...... at different pulse frequencies. Based on the restoration of equilibrium, the relaxation process of the soil-water system was investigated by chronopotentiometric analysis to find the optimal relaxation time for energy saving. Results showed that the pulse current decreased the energy consumption with different...... extent depending on the pulse frequency. The experiment with the frequency of 16 cycles per day showed the best restoration of equilibrium and lowest energy consumption. The energy consumption per removed heavy metals was lower in pulse current experiments than constant current and increased...

  4. Oxalic acid as an assisting agent for the electrodialytic remediation of chromated copper arsenate treated timber waste

    DEFF Research Database (Denmark)

    Ribeiro, Alexandra B.; Mateus, Eduardo P.; Ottosen, Lisbeth M.

    1999-01-01

    The electrodialytic process is proposed as a technique for the remediation of chromated copper arsenate treated timber waste, using oxalic acid as assisting agent. The method prowed succesfull 93% Cu, 95% Cr and 99% As was removed from the timber.......The electrodialytic process is proposed as a technique for the remediation of chromated copper arsenate treated timber waste, using oxalic acid as assisting agent. The method prowed succesfull 93% Cu, 95% Cr and 99% As was removed from the timber....

  5. Electrodialytic soil remediation enhanced by low frequency pulse current

    DEFF Research Database (Denmark)

    Mortensen, John; Sun, Tian Ran; Ottosen, Lisbeth M.

    2013-01-01

    The effect of low frequency pulse current on decreasing the polarization and energy consumption during the process of electrodialytic soil remediation was investigated in the present work. The results indicated that the transportation of cations through the cation exchange membrane was the rate...... current experiment compared to the constant current experiment. At the cation exchange membrane, only the resistance caused by concentration polarization decreased. In the soil compartment, an average of +60 mV overpotential caused by the polarization of the electric double layer of the clay particles...... controlling step both in constant and pulse current experiments, thus responsible for the major energy consumption. After 180 h, a decrease in both the initial ohmic resistance in each pulse cycle and the resistance caused by concentration polarization of the anion exchange membrane were seen in the pulse...

  6. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process

    DEFF Research Database (Denmark)

    Dias-Ferreira, Celia; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0...... to remediate metal polluted soils at neutral to alkaline pH by choosing a good enhancement solution.......Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0.......25, 0.5 and 1.0 M) and remediation times (21, 42 and 117 d) for the removal of Cu and Cr from a calcareous soil. To gain insight on metal behavior, soil solution was periodically collected using suction cups. It was seen that current densities higher than 1.0 mA cm−2 did not increase removal and thus...

  7. Ammonium citrate as enhancement for electrodialytic soil remediation and investigation of soil solution during the process

    DEFF Research Database (Denmark)

    Dias-Ferreira, Celia; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2015-01-01

    Seven electrodialytic experiments were conducted using ammonium citrate as enhancing agent to remediate copper and chromium-contaminated soil from a wood-preservation site. The purpose was to investigate the effect of current density (0.2, 1.0 and 1.5 mA cm−2), concentration of enhancing agent (0...... using too high current densities can be a waste of energy. Desorption rate is important and both remediation time and ammonium citrate concentration are relevant parameters. It was possible to collect soil solution samples following an adaptation of the experimental set-up to ensure continuous supply...... of ammonium citrate to the soil in order to keep it saturated during the remediation. Monitoring soil solution gives valuable information on the evolution of remediation and helps deciding when the soil is remediated. Final concentrations in the soil ranged from 220 to 360 mg Cu kg−1 (removals: 78...

  8. Electrodialytic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, A.; Ottpsen, Lisbeth M.

    2005-01-01

    electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper from watery tailing if the potential gradient was higher than 2V/cm during 21 days. With addition of sulphuric acid, the process was enhanced because the pH decreased to around 4......, and the copper by this reason was released in the solution. Furthermore, with acidic tailing the potential gradient was less than 2V/cm.The maximum copper removal reached in the anode side was 53% with addition of sulphuric acid in 21 days experiment at 20V using approximately 1.8kg mine tailing on dry basis....... In addition, experiments with acidic tailing show that the copper removal is proportional with time....

  9. Electrodialytic versus acid extraction of heavy metals from soil washing residue

    DEFF Research Database (Denmark)

    Jensen, Pernille E.; Ottosen, Lisbeth M.; Allard, Bert

    2012-01-01

    The feasibility of electrodialytic remediation (EDR) for treatment of suspended sludge after soil washing is in focus in the present paper. Five industrially contaminated soils were treated in laboratory scale remediation experiments, and the toxic elements of the investigation were: As, Cd, Cu, Cr......, Ni, Zn and Pb. The results showed that all investigated elements could be removed from all soils to some extent by EDR. For all anthropogenic contaminants, higher extraction can be obtained under the influence of the direct current during EDR than by washing. During EDR most elements were transferred...... explained well by the hydrolytic chemistry of the elements, with a difference between the soils. The only element transported primarily towards the anode, was arsenic suggesting that As(V) is the dominating species, and showing that As(III) is oxidized during the remediation process. In contrast the kinetic...

  10. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie;

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...... of the treated products for reuse in construction or farming sectors should be explored further, as should the possibility of recycling of valuable, extracted elements in the metallurgical industry....

  11. Electrodialytic remediation of solid waste

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Karlsmose, Bodil;

    1996-01-01

    Electrodialytic remediation of heavy metal polluted solid waste is a method that combines the technique of electrodialysis with the electromigration of ions in the solid waste. Results of laboratory scale remediation experiments of soil are presented and considerations are given on how to secure...... fly ash waste deposits from polluting the ground water....

  12. Elemental analysis of ash residue from combustion of CCA treated wood waste before and after electrodialytic extraction

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.

    2006-01-01

    Element distribution in a combined fly ash and bottom ash from combustion of copper chromate arsenate (CCA) treated wood waste was investigated by scanning electron microscopy (SEM/EDX) before and after electrodialytic extraction. The untreated ash contained various particles, including pieces...... treatment. Instead particles rich in Ca and S were now found, indicating precipitation of Ca-sulphates due to addition of sulphuric acid in connection with the electrodialytic treatment. Cu and Cr were still found associated with incompletely combusted wood particles and incorporated in matrix particles....... Chemical analyses of untreated and treated ash confirmed that most As, but only smaller amounts of Cu and Cr was removed due to the electrodialytic extraction. Overall metal contents in the original ash residue were: 1.4 g As, 2.76 g Cu and 2.48 g Cr, after electrodialytic extraction these amounts were...

  13. Electrodialytic removal of nitrate from pineapple juice: effect on selected physicochemical properties, amino acids, and aroma components of the juice.

    Science.gov (United States)

    Ackarabanpojoue, Yuwadee; Chindapan, Nathamol; Yoovidhya, Tipaporn; Devahastin, Sakamon

    2015-05-01

    This study aimed at investigating the effect of nitrate removal from pineapple juice by electrodialysis (ED) on selected properties of the ED-treated juice. Single-strength pineapple juice with reduced pulp content was treated by ED to reduce the nitrate concentration to 15, 10, or 5 ppm. After ED, the removed pulp was added to the ED-treated juice and its properties, including electrical conductivity, acidity, pH, total soluble solids (TSS), color, amino acids, and selected aroma compounds, were determined and compared with those of the untreated juice. ED could reduce the nitrate content of 1 L of pineapple juice from an initial value of 50 ppm to less than 5 ppm within 30 min. A significant decrease in the electrical conductivity, acidity, pH, TSS, and yellowness, but a significant increase in the lightness, of the juice was observed upon ED. Concentrations of almost all amino acids of the ED-treated juice significantly decreased. The concentrations of 8 major compound contributors to the pineapple aroma also significantly decreased. Adding the pulp back to the ED-treated juice increased the amino acids concentrations; however, it led to a significant decrease in the concentrations of the aroma compounds.

  14. Suspended electrodialytic extraction of toxic elements for detoxification of three different mine tailings

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Hansen, H.K.;

    2016-01-01

    investigated including pre-treatment of the tailings with acid; insertion of bipolar electrodes; and implementation of pulsed or sinusoidal electric fields. In line with these efforts, we investigated the efficiency when extracting toxic elements from a suspension of tailings, rather than from a solid matrix......, which could well be implemented as a final treatment step prior to deposition of tailings. Six electrodialytic experiments in laboratory scale with three different mine tailings (Codelco, Zinkgruvan, and Nalunaq) show that it is possible to extract residual Cu from the all the three suspended mine...... have shown that electrokinetic treatment can remove Cd, Cu, Pb, and Zn from tailings soils; As from tailings; and Cu from tailings. Still, however, a major concern is the long treatment-time required for the element-transport through the tailings matrix. Therefore several enhancement methods have been...

  15. Electrodialytic Remediation of Copper Mine Tailings

    DEFF Research Database (Denmark)

    Hansen, H.K.; Rojo, A.; Ottosen, L.M.

    2012-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields.......This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields....

  16. Electrodialytic removal of cadmium from wastewater sludge

    DEFF Research Database (Denmark)

    Jakobsen, M. R.; Fritt-Rasmussen, Janne; Nielsen, S.;

    2004-01-01

    This paper presents for the first time laboratory results demonstrating electrodialytic removal of Cd from wastewater sludge, which is a method originally developed for soil remediation. During the remediation a stirred suspension of wastewater sludge was exposed to an electric dc field. The liquid...... in contact with atmospheric air. A combination of aerobic decomposition and electrodialytic treatment could be a promising method for Cd removal from wastewater sludge, and thus Cd could be removed without the addition of chemicals to the sludge....

  17. Electrodialytic Removal of Cadmium from Straw Ash

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne;

    1999-01-01

    A problem with flyash from straw and wood combustion is the high level of heavy metals, especially cadmium. Two electrodialytic remediation experiments were carried out on cadmium polluted flyash from straw combustion. The flyash could be cleaned to 1/3 of its initial level after 24 days...

  18. Electrodialytic decontamination of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Karlsmose, Bodil

    1996-01-01

    Electrodialytic remediation of heavy metal polluted soil is a newly developed method, which combines the electrokinetic mevement of ions in soil with the principle of electrodialytis. The method has been proven to work in laboratory scale and at present two types of pilot plant tests are made....

  19. Metal speciation of historic and new copper mine tailings from Repparfjorden, Northern Norway, before and after acid, base and electrodialytic extraction

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    2016-01-01

    the new mine tailings. Electrodialysis, based on applying an electric field of low intensity to extract metals from polluted soils/sediments, was designed for acidic and alkaline extraction, and in both cases more Cu was extracted than in the pure acid/base extractions, while maintaining low mobilisation...

  20. Electrodialytic remediation of suspended mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrian; Pino, Denisse;

    2008-01-01

    This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. A newly designed remediation cell, where the solids were kept in suspension by airflow, was tested. The results show that electric current could remove copper from suspended tailings...... experiment at 40 mA, with approximately 137.5 g mine tailings on dry basis. The removal for a static (baseline) experiment only amounted 15% when passing approximately the same amount of charge through 130 g of mine tailings. The use of air bubbling to keep the tailings suspended increased the removal...

  1. Electrodialytic remediation of soil polluted with heavy metals

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Hansen, Lene;

    1999-01-01

    In this paper, the importance of some parameters for the efficiency of electrodialytic soil remediation are evaluated. The parameters investigated are pH, the limiting current density and the addition of desorbing agents to the soil. These three parameters are found to be of the greatest importance....... results show that electrodialytic soil remediation can be optimized by understanding and adjusting these parameters. For scaling up the remediation method, these parameters are of crucial importance....

  2. Electrodialytic separation of Cu(II) and As(V) in acidic electrolytes; Separacion electrodialitica de Cu(II) y As(V) en electrolitos acidos

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, J. P.; Ipinza, J.; Cifuentes, L.

    2007-07-01

    The separation of copper and arsenic from acidic electrolytes by electrodialysis was investigated at room temperature. the effect of current density and pH was studied in a batch cell during 3 hours. The kinetic parameters showed that Cu(II) transport rate was 0.75 mol/m''2/h and the As(V) transport rate was 0.002 mol/m''2/h. An efficient separation between Cu(II) and As(V) was achieved; Generating a concentrated solution of copper with no arsenic, which was obtained independently of the electrolyte acidity and current density used. The effect of the arsenic speciation with pH is discussed as well. (Author) 23 refs.

  3. Electrodialytic remediation of copper mine tailings using bipolar electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Rojo, Adrian, E-mail: adrian.rojo@usm.cl [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Cubillos, Luis [Departamento de Ingenieria Quimica y Ambiental, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile)

    2009-09-15

    In this work an electrodialytic remediation (EDR) cell for copper mine tailings with bipolar stainless steel plates was analyzed. The bipolar plates were inserted inside the tailings, dividing it into independent electrochemical cells or sections, in order to increase the copper removal efficiency from mine tailings. The bipolar plates design was tested on acidic copper mine tailings with a fixed: applied electric field, liquid content, initial pH, and remediation time. The laboratory results showed that inserting bipolar plates in EDR cells improves the remediation action, even though the applied electric field is reduced by the electrochemical reactions on the plates. Basically three aspects favor the process: reduction of the ionic migration pathways, increase of the electrode surface, and in-situ generation of protons (H{sup +}) and hydroxyls (OH{sup -}). Furthermore, the laboratory results with citric acid addition significantly improve the remediation actions, reaching copper removal of up to nine times better, compared to conventional EDR experiments without any plates or citric acid addition.

  4. Electrodialytic remediation of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie;

    2012-01-01

    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses...... without a short distance between the membranes. The acidification of the suspended soil was fastest and following the mobilization of heavy metals. This may indicate that water splitting at the anion exchange membrane is used more efficiently in the stirred setup........ The first as in-situ or on-site treatment when there is no requirement for fast remediation, as the removal rate of the heavy metals are dependent on the distance between the electrodes (everything else equal) and in such application the electrode spacing must have a certain distance (often meters...

  5. Electrodialytic remediation of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2012-01-01

    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses......). In the stirred setup it is possible to shorten the transport route to few mm and to have a faster and continuous process. The present paper for the first time reports a direct comparison of the two options. The remediation of the stirred suspension showed faster than remediation of the water saturated soil even...... without a short distance between the membranes. The acidification of the suspended soil was fastest and following the mobilization of heavy metals. This may indicate that water splitting at the anion exchange membrane is used more efficiently in the stirred setup....

  6. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

    The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration.......The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration....

  7. Electrodialytic remediation of CCA treated waste wood in pilot scale

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Christensen, Iben Vernegren; Ottosen, Lisbeth M.;

    2005-01-01

    When CCA (Chromated Copper Arsenate) treated wood is removed from service and turns into waste, the contents of Cu, Cr and As is still high due to the strong fixation of CCA in the wood. This high content of toxic compounds presents a disposal challenge. Incineration of CCA treated waste wood...... study the utility of the method Electrodialytic Remediation was demonstrated for handling of CCA treated waste wood in pilot scale. The electrodialytic remediation method, which uses a low level DC current as the cleaning agent, combines elektrokinetic movement of ions in the wood matrix with the princi...

  8. Effect of different extracting solutions on the electrodialytic remediation of CCA-treated wood waste Part I. - Behaviour of Cu and Cr

    DEFF Research Database (Denmark)

    Velizarova, E.; Ribeiro, A. B.; Mateus, E.

    2004-01-01

    Removal of Cu and Cr from chromated copper arsenate (CCA)-treated wood waste under batch electrodialytic conditions was studied. The effect of different types of extracting solutions, such as deionised water or aqueous solutions of NaCl, formic acid, oxalic acid, and EDTA, on the magnitude...... and direction of the fluxes of Cu- and Cr-containing species in the electrodialytic cell was investigated. Oxalic acid was found to have the best performance if simultaneous removal of the two elements is required (removal efficiencies of 80.5% for Cu and 87.4% for Cr, respectively). A mixture of oxalic acid....... The latter were not present if EDTA was the extracting solution resulting in directing the Cu and Cr fluxes to the anode compartment. Contrary, these fluxes were exclusively to the cathode compartment if deionised water or an aqueous solution of NaCl were used. These extracting solutions proved suitable...

  9. Ultrathin Sicopion Composite Cation-Exchange Membranes: Characteristics and Electrodialytic Performance following a Conditioning Procedure

    Directory of Open Access Journals (Sweden)

    Erik Ayala-Bribiesca

    2012-01-01

    Full Text Available The aim of this work was to investigate the properties of Sicopion membranes: an ultrathin (≈20 μm composite cation-exchange membrane (CEM made from sulphonated poly(ether-ether-ketone (SPEEK containing different levels of sulphonic-functionalized silica particles (SFSPs. Sicopion membranes were conditioned according to the French Normalization Association procedure, consisting in a series of acid and alkaline washes, and their electrodialytic characteristics were compared to an existent commercial food-grade membrane (CMX-SB. Electrical conductivity of Sicopion membranes was higher than that of CMX-SB membranes (9.92 versus 6.98 mS/cm, as well as their water content (34.0 versus 27.6%. As the SFSP level was reduced, the ion-exchange capacity (IEC of Sicopion membranes increased. Concerning their electrodialytic performances, Sicopion membranes presented a lower demineralization rate than CMX-SB membranes (35.9 versus 45.5%, due to an OH− leakage through the pores created by dislodging the SFSP particles during the conditioning procedure.

  10. Phosphorus recovery from sewage sludge ash through an electrodialytic process

    DEFF Research Database (Denmark)

    Guedes, Paula; Couto, Nazare; Ottosen, Lisbeth M.

    2014-01-01

    The electrodialytic separation process (ED) was applied to sewage sludge ash (SSA) aiming at phosphorus (P) recovery. As the SSA may have high heavy metals contents, their removal was also assessed. Two SSA were sampled, one immediately after incineration (SA) and the other from an open deposit (SB...

  11. Electrodialytic remediation of copper mine tailings: Comparing different operational conditions

    DEFF Research Database (Denmark)

    Rojo, Adrian; Hansen, Henrik K.; Ottosen, Lisbeth M.

    2006-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analyzed, such as remediation time, voltage drop, addition of desorbing agents, and the use of pulsed electrical fields. The results show that electric cu...

  12. Electrodialytic recovery of phosphorus from chemically precipitated sewage sludge ashes

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    Phosphorus scarcity requires improved recover and reuse of urban sources; the recycling of this nutrient from sewage sludge has become increasingly important in the last years. Using an innovative electrodialytic process, the present study shows the potential for P separation from Fe and Al...

  13. Electrodialytic Remediation of Heavy Metal Polluted Soil. An Innovative Technique

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik; Karlsmose, Bodil

    1997-01-01

    Electrodialytic remediationof heavy metal polluted soil is a newly developed method which combines the electrokinetic movement of ions in soil with the principle of electrodialysis. The method has prowen to work in laboratorscale and at presnet two types of pilot plants are build....

  14. Electrodialytic remediation of soil polluted with heavy metals

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Hansen, Lene;

    1999-01-01

    In this paper, the importance of some parameters for the efficiency of electrodialytic soil remediation are evaluated. The parameters investigated are pH, the limiting current density and the adding of desorbing agents to the soil. Three parameters are found to be of greatest importance. Results ...

  15. Predicting scale formation during electrodialytic nutrient recovery.

    Science.gov (United States)

    Thompson Brewster, Emma; Ward, Andrew J; Mehta, Chirag M; Radjenovic, Jelena; Batstone, Damien J

    2017-03-01

    Electro-concentration of nutrients from waste streams is a promising technology to enable resource recovery, but has several operational concerns. One key concern is the formation of inorganic scale on the concentrate side of cation exchange membranes when recovering nutrients from wastewaters containing calcium, magnesium, phosphorous and carbonate, commonly present in anaerobic digester rejection water. Electrodialytic nutrient recovery was trialed on anaerobic digester rejection water in a laboratory scale electro-concentration unit without treatment (A), following struvite recovery (B), and following struvite recovery as well as concentrate controlled at pH 5 for scaling control (C). Treatment A resulted in large amount of scale, while treatment B significantly reduced the amount of scale formation with reduction in magnesium phosphates, and treatment C reduced the amount of scale further by limiting the formation of calcium carbonates. Treatment C resulted in an 87 ± 7% by weight reduction in scale compared to treatment A. A mechanistic model for the inorganic processes was validated using a previously published general precipitation model based on saturation index. The model attributed the reduction in struvite scale to the removal of phosphate during the struvite pre-treatment, and the reduction in calcium carbonate scale to pH control resulting in the stripping of carbonate as carbon dioxide gas. This indicates that multiple strategies may be required to control precipitation, and that mechanistic models can assist in developing a combined approach.

  16. The effect of soil type on the electrodialytic remediation of lead-contaminated soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Harmon, Thomas C.

    2007-01-01

    experiments with ten representative industrially Pb-contaminated surface soils. Results indicate that Pb-speciation is of primary importance. Specifically, organic matter and stable compounds like PbCrO4 can impede and possibly even preclude soil remediation. In soils rich in carbonate, where the acidic front......This work investigates the influence of soil type on electrodialytic remediation (EDR) of lead (Pb). It is well-known in electrokinetic soil remediation that pH is a key factor, and carbonate influences remediation efficiency negatively. This work provides results from laboratory scale EDR...... is impeded, part of the Pb can be transferred from the soil to the anolyte as negatively charged complexes during the EDR process. The dominant complex is in this case likely to be Pb(CO3)22-. Efficient remediation is however not obtained until all carbonate has dissolved and Pb2+ is transported...

  17. Electrodialytic removal of Cd from biomass combustion fly ash suspensions

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor M.; Ottosen, Lisbeth M.; Damoe, Anne J.

    2013-01-01

    Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes was invest......Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes...... the final Cd concentration was below 2.0. mg Cd/kg DM in at least one experiment done with each ash. This was obtained within 2 weeks of remediation and at liquid to solid (L/S) ratios of L/S 16 for the pre-washed straw ash and L/S 8 for the straw, co-firing and wood ash. © 2013 Elsevier B.V....

  18. Electrodialytic Removal of Heavy Metals from Different Solid Waste Products

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Christensen, Iben Vernegren; Pedersen, Anne Juul;

    2003-01-01

    that the method could be used for removal of different heavy metals from impregnated wood waste, fly ash from straw combustion, and fly ash from municipal solid waste incineration. The best result was obtained with the wood waste where more than 80% of each of the polluting elements Cu, Cr and As was removed......A variety of heavy metal polluted waste products must be handled today. Electrochemical methods have been developed for remediation of polluted soil. One of the methods is the electrodialytic remediation method that is based on electromigration of heavy metal ions and ionic species within the soil...... could be used when removing Cu and Cr from a soil with 25% carbonates. The final concentrations of the elements were below the target values after the remediation. A question of whether the electrodialytic remediation method can be used for other waste products arose. Preliminary experiments showed...

  19. Electrodialytic recovery of phosphorus from chemically precipitated sewage sludge ashes

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    Phosphorus scarcity requires improved recover and reuse of urban sources; the recycling of this nutrient from sewage sludge has become increasingly important in the last years. Using an innovative electrodialytic process, the present study shows the potential for P separation from Fe and Al preci...... precipitated sewage sludge ash using this technique, with a recovery rate of around 70%. Furthermore, heavy metals were removed from the phosphorous fraction, producing a pure and safe phosphorus source in the end....

  20. Electrodialytic recovery of phosphorus from chemically precipitated sewage sludge ashes

    DEFF Research Database (Denmark)

    Viader, Raimon Parés; Erland Jensen, Pernille; Ottosen, Lisbeth M.;

    Phosphorus scarcity requires improved recover and reuse of urban sources; the recycling of this nutrient from sewage sludge has become increasingly important in the last years. Using an innovative electrodialytic process, the present study shows the potential for P separation from Fe and Al preci...... precipitated sewage sludge ash using this technique, with a recovery rate of around 70%. Furthermore, heavy metals were removed from the phosphorous fraction, producing a pure and safe phosphorus source in the end...

  1. Enhancement of colposcopic image by sulphosalicylic acid.

    Directory of Open Access Journals (Sweden)

    Khilnani P

    1993-01-01

    Full Text Available Acetic acid is used conventionally for enhancement of the colposcopic image. We used sulphosalicylic acid instead of acetic acid in 50 normal cases. The normal appearance was enhanced in all cases. The image was also enhanced in 70% cases of cervical intraepithelial neoplasia and 90% cases of cervical condyloma accuminata. The image was not inferior to that with acetic acid in any of the cases.

  2. Electrodialytic removal of cadmium from straw combustion fly ash

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Villumsen, Arne

    2004-01-01

    Fly ash from straw combustion contains valuable nutrients when returned to agricultural soils. In many instances, however, this fly ash may contain heavy metals, such as cadmium, at levels which often exceed the limits given by the Danish legislation. Thus before utilizing the nutrients, cadmium...... must be removed from these ashes. The use of an electrodialytic remediation method to remove cadmium from fly ash arising from straw combustion and containing 11.2 mg Cd kg$+-1$/ DM (dry matter) was accessed. After 36 days of remediation at a constant current density of 5.6 mA cm$+-2$/ more than 97...

  3. Electrodialytic removal of Cd from biomass combustion fly ash

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Simonsen, Peter

    2004-01-01

    Due to a high concentration of Cd, biomass combustion fly ash often fails to meet the Danish legislative requirements for recycling on agricultural fields. In this work the potential of using the method Electrodialytic Remediation to reduce the concentration of Cd in different biomass combustion...... four ashes. Final Cd concentrations below 2.0 mg Cd/kg were reached in all ashes within 14 days of remediation and legislative requirements were met. After further optimization of the remediation process on the pre-washed straw ash, limiting concentrations were reached after only 48 hours...

  4. Electrodialytic extraction of Cd and Cu from sediment from Sisimiut Harbour, Greenland

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Nystrøm, Gunvor Marie; Jensen, Pernille Erland;

    2007-01-01

    concentration with 80%). Thus a large reduction in concentrations can be obtained relatively fast. During the process of electrodialytic treatment the sediment suspension is acidified and reaches pH 2 after about 3 days (with 0.5 mA cm2), where it stabilizes. A comparison with chemical extraction in HNO3...... at about the same pH showed that 50-70% more Cu and 11% more Cd was removed during the electrodialytic treatment....

  5. Electrodialytic extraction of heavy metals from Greenlandic MSWI fly ash as a function of remediation time and L/S ratio

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2013-01-01

    was characterized before and after the electrodialytic remediation experiments for heavy metals content, amount of soluble heavy metals and pH. Before the electrodialytic experiments the water solubility of Ba, Cr and Pb was high from the alkaline fly ash. Six electrodialytic remediation experiments were made...... lasting 14 days with L/S 10, up to 60 % Cd, 45 % Zn, 20 % Ni and Ba was removed. Regardless of the remediation time and L/S ratio, the fraction of soluble Ba, Cr and Pb decreased due to the electrodialytic remediation. The electrodialytic remediation method showed potential as a treatment method...

  6. Electrodialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Electrodialytic remediation, an electrochemically assisted separation method, has previ-ously shown potential for removal of heavy metals from municipal solid waste incineration (MSWI) fly ashes. In this work electrodialytic remediation of MSWI fly ash using ammonium citrate as assisting agent...

  7. Electrodialytic removal of heavy metals from different fly ashes. Influence of heavy metal speciation in the ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2003-01-01

    Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied...

  8. Electrodialytic soil remediation in a small pilot plant (Part II)

    DEFF Research Database (Denmark)

    Karlsmose, Bodil; Hansen, Lene

    1999-01-01

    (XRD), transmission electron microscope (TEM) and observations with scanning electron microscope (SEM), the last two combined with an EDX analysis unit. The three soil fractions were extracted with am-monia for observa-tion of the copper removal when copper forms copper-tetra-ammine complexes with am......-monia. Ammonia was chosen because it forms strong complexes with copper and to keep the soil basic, so that the carbonates were not dissolved. The bulk soil was treated by electrodialytic reme-dia-tion, and soil treated for seven months was investigated with XRD, TEM and SEM.Malachite was found by use of XRD...... measurements in one of the untreated soil samples. These measurements were supported by EDX measurements (combined with either SEM or TEM), where almost pure copper particles were found. The EDX measurements do not include hydrogen, carbon and oxygen, which make the figures of all other elements higher than...

  9. Electrical Resistance and Transport Numbers of Ion-Exchange Membranes Used in Electrodialytic Soil Remediation

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne

    1999-01-01

    causes damage to the membrane. This work presents the result from transport number and electrical resistance measurements done on four sets of ion-exchange membranes (Ionics, Inc. CR67 HMR412 cation-exchange membranes and Ionics, Inc. AR204 SXZR anion-exchange membranes), which have been used in four......Electrodialytic soil remediation is a recently developed method to decontaminate heavy metal polluted soil using ion-exchange membranes. In this method one side of the ion-exchange membrane is in direct contact with the polluted soil. It is of great importance to know if this contact with the soil...... different electrodialytic soil remediation experiments. The experiments showed that after the use in electrodialytic soil remediation, the ion-exchange membranes had transport numbers in the same magnitude as new membranes. The electrical resistance for six membranes did not differ from that of new...

  10. Acidification of Harbour sediment and removal of heavy metals induced by water splitting in electrodialytic remediation

    DEFF Research Database (Denmark)

    Nystrøm, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Harbor sediments are often contaminated with heavy metals, which can be removed by electrodialytic remediation. Water splitting at the anion exchange membrane in contact with the contaminated material in electrodialytic remediation is highly important for the removal of heavy metals. Here...... it was investigated how acidification caused by water splitting at the anion exchange membrane during electrodialytic remediation of contaminated harbor sediment and hence the metal removal, was influenced by different experimental conditions. Two different experimental cells were tested, where the number...... the sediment was acidified, the voltage decreased and electrical conductivity increased. After 5 days of remediation the sediment was acidified at the chosen current density (1 mA/cm(2)) and the main metal removal was observed shortly after. Thus it was crucial for the metal removal that the sediment was fully...

  11. Removal of selected heavy metals from MSW fly ash by the electrodialytic process

    DEFF Research Database (Denmark)

    Ferreira, Célia Maria Dias; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    2005-01-01

    This paper aims to assess the applicability of the electrodialytic remediation technique for the removal of zinc, lead, copper and cadmium from municipal solid waste (MSW) incinerator fly ash. A broad range of experimental conditions were studied including current densities, remediation times, use...... of assisting agents and cell design. Several operational problems were identified during the electrodialytic experiments, among which are formation of precipitates, dryness of sample and partial dissolution of sample creating preferential pathways for the electric current. These problems may explain the low...

  12. Test of electrodialytic upgrading of MSWI APC residue in pilot scale: focus on reduced metal and salt leaching

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Jensen, Pernille Erland; Villumsen, Arne

    2010-01-01

    In this study a pilot plant for electrodialytic treatment of municipal solid waste incineration (MSWI) air pollution control (APC) residue was tested and proposed as a treatment method which can lead to reuse of this otherwise hazardous waste. The pilot plant was developed based on a design...... that is adapted from conventional electrodialysis, e.g. used in desalination of solutions. The APC residue was treated in a suspension (8 kg APC residue and 80 L tap water) and circulated through an electrodialytic (ED) stack consisting of 50 cell pairs separated by ion exchange membranes. A direct current...... and could not stand as a treatment method alone. Leaching of both heavy metals and salts were significantly reduced by the electrodialytic treatment for both the raw and carbonated APC residue. In the electrodialytically treated carbonated APC residue only Cr exceeded the Category 3 levels while...

  13. Electrodialytic remediation of municipal solid waste incineration residues using different membranes

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2017-01-01

    In the present work, three different commercial membrane brands were used in an identical electrodialytic cell setup and operating conditions, in order to reduce the leaching of metals and salt anions of two types of municipal solid waste incineration residues: air pollution control residues...... as a technology to upgrade municipal solid waste incineration residues....

  14. Characterization of municipal solid waste incineration fly ash before and after electrodialytic treatment

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Gardner, Kevin H.

    2003-01-01

    Municipal solid waste incineration (MSWI) fly ash, which has been treated electrodialytically for the removal of heavy metals, may have changed characteristics compared to untreated fly ash. In this study, MSWI fly ash was characterized with respect to leaching properties (pH static leaching...

  15. Electrodialytic upgrading of MSWI APC residue from hazardous waste to secondary resource

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Kirkelund, Gunvor Marie; Parés Viader, Raimon

    The aim of this project was to contribute to the development of electrodialytic treatment technology of air pollution control residues (APC) from municipal solid waste incineration (MSWI) to obtain maximal leaching reduction by optimization of treatment time and current density for different types...

  16. Sequential electrodialytic recovery of phosphorus from low-temperature gasification ashes of chemically precipitated sewage sludge

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2017-01-01

    availability and the presence of heavy metals. Previously, more than 80% of P was recovered from incineration sewage sludge ashes using a two-compartment electrodialytic cell. In contrast, the recovery was below 30% for ashes from low-temperature gasification using the same setup. The low recovery was due...

  17. Effects of pulse current on energy consumption and removal of heavy metals during electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Sun, Tian R.; Ottosen, Lisbeth M.

    2012-01-01

    The aims of this paper were to investigate the possibility for energy saving when using a pulsed electric field during electrodialytic soil remediation (EDR) and the effect of the pulsed current on removal of heavy metals. Eight experiments with constant and pulse current in the different industr...

  18. Electrodialytic Remediation of Soil Fines (<63μm) in Suspension

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Ferreira, Célia

    2007-01-01

    Current treatment of the remaining soil fines from soil wash is onerous and expensive, and therefore, in this work, we investigated the feasibility of electrodialytic remediation (EDR) as an alternative treatment. The study focuses on EDR efficiency as a function of current strength, liquid-to-so...

  19. An optimised method for electrodialytic removal of heavy metals from harbour sediments

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    2015-01-01

    A 2-compartment electrodialytic cell set-up for treatment of solid materials has in many respects proven superior to other types of cells in removing heavy metals from sediments. Most notably, remediation times were shorter, energy consumption was lower and higher removal efficiencies were observed...

  20. Electrodialytic membrane suppressors for ion chromatography make programmable buffer generators.

    Science.gov (United States)

    Chen, Yongjing; Srinivasan, Kannan; Dasgupta, Purnendu K

    2012-01-01

    The use of buffer solutions is immensely important in a great variety of disciplines. The generation of continuous pH gradients in flow systems plays an important role in the chromatographic separation of proteins, high-throughput pK(a) determinations, etc. We demonstrate here that electrodialytic membrane suppressors used in ion chromatography can be used to generate buffers. The generated pH, computed from first principles, agrees well with measured values. We demonstrate the generation of phosphate and citrate buffers using a cation-exchange membrane (CEM) -based anion suppressor and Tris and ethylenediamine buffers using an anion-exchange membrane (AEM) -based cation suppressor. Using a mixture of phosphate, citrate, and borate as the buffering ions and using a CEM suppressor, we demonstrate the generation of a highly reproducible (avg RSD 0.20%, n = 3), temporally linear (pH 3.0-11.9, r(2) > 0.9996), electrically controlled pH gradient. With butylamine and a large concentration (0.5 M) of added NaCl, we demonstrate a similar linear pH gradient of large range with a near-constant ionic strength. We believe that this approach will be of value for the generation of eluents in the separation of proteins and other biomolecules and in online process titrations.

  1. Enhanced acid tolerance of Rhizopus oryzae during fumaric acid production.

    Science.gov (United States)

    Liu, Ying; Lv, Chunwei; Xu, Qing; Li, Shuang; Huang, He; Ouyang, Pingkai

    2015-02-01

    Ensuring a suitable pH in the culture broth is a major problem in microorganism-assisted industrial fermentation of organic acids. To address this issue, we investigated the physiological changes in Rhizopus oryzae at different extracellular pH levels and attempted to solve the issue of cell shortage under low pH conditions. We compared various parameters, such as membrane fatty acids' composition, intracellular pH, and adenosine triphosphate (ATP) concentration. It was found that the shortage of intracellular ATP might be the main reason for the low rate of fumaric acid production by R. oryzae under low pH conditions. When 1 g/l citrate was added to the culture medium at pH 3.0, the intracellular ATP concentration increased from 0.4 to 0.7 µmol/mg, and the fumaric acid titer was enhanced by 63% compared with the control (pH 3.0 without citrate addition). The final fumaric acid concentration at pH 3.0 reached 21.9 g/l after 96 h of fermentation. This strategy is simple and feasible for industrial fumaric acid production under low pH conditions.

  2. Electrodialytic Remediation of Pb Contaminated Soil - Effects of Soil Properties and Pb Distribution

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Jensen, Pernille Erland

    1999-01-01

    The aim of this work was to investigate the effects of soil properties and Pb distribution on the electrodialytic remediation of Pb contaminated soil. Two naturally Pb contaminated soils were compared with respect to total Pb content, Pb distribution, pH, carbonate content, clay content and organic...... matter, and an electrodialytic remediation experiment was made on each soil.It was concluded that soil pH was the most important factor limiting the mobilisation of Pb. In one of the remediation experiments it was possible to mobilise and reduce the amount of Pb significantly, whereas in the other only...... a small amount of the initial Pb was mobilised at similar experimental conditions. A high buffering capacity of one of the soils, which was partly due to a high carbonate content, led to a bad remediation result....

  3. Comparison of electrodialytic removal of Cu from spiked kaolinite, spiked soil and industrially polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Lepkova, Katarina; Kubal, Martin

    2006-01-01

    Electrokinetic remediation methods for removal of heavy metals from polluted soils have been subjected for quite intense research during the past years since these methods are well suitable for fine-grained soils where other remediation methods fail. Electrodialytic remediation is an electrokinetic...... remediation method which is based on applying an electric DC field and the use of ion exchange membranes that ensures the main transport of heavy metals to be out of the pollutes soil. An experimental investigation was made with electrodialytic removal of Cu from spiked kaolinite, spiked soil and industrially...... polluted soil under the same operational conditions (constant current density 0.2 mA/cm2 and duration 28 days). The results of the present paper show that caution must be taken when generalising results obtained in spiked kaolinite to remediation of industrially polluted soils, as it was shown...

  4. Method for enhancing amidohydrolase activity of fatty acid amide hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    John, George; Nagarajan, Subbiah; Chapman, Kent; Faure, Lionel; Koulen, Peter

    2016-10-25

    A method for enhancing amidohydrolase activity of Fatty Acid Amide Hydrolase (FAAH) is disclosed. The method comprising administering a phenoxyacylethanolamide that causes the enhanced activity. The enhanced activity can have numerous effects on biological organisms including, for example, enhancing the growth of certain seedlings. The subject matter disclosed herein relates to enhancers of amidohydrolase activity.

  5. Mercury Levels In Fly Ash And Apc Residue From Municipal Solid Waste Incineration Before And After Electrodialytic Remediation

    DEFF Research Database (Denmark)

    Dias-Ferreira, Celia; Kirkelund, Gunvor Marie; Jensen, Pernille Erland

    2016-01-01

    Fly ash (FA) and Air Pollution Control (APC) residues collected from three municipal solid waste incinerators (MSWI) in Denmark and Greenland were treated by electrodialytic remediation at pilot scale for 8 to 10 h. The original residues and the treated material were analysed for mercury (Hg...

  6. Evaluation of assisting agents for electrodialytic removal of Cd, Pb, Zn, Cu and Cr from MSWI fly ash

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2002-01-01

    Different assisting agents (0.25 M ammonium citrate/1.25 % NH3, 0.25 M Na-citrate, 2.5 % NH3, DI water) have been used as assisting agents for the removal of heavy met-als during electrodialytic treatment of municipal solid waste incineration (MSWI) fly ash. In this study, the effectiveness...

  7. Comparison of 2-compartment, 3-compartment and stack designs for electrodialytic removal of heavy metals from harbour sediments

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Ottosen, Lisbeth M.; Jensen, Pernille Erland;

    2015-01-01

    Comparisons of cell and stack designs for the electrodialytic removal of heavy metals from two harbour sediments, were made. Multivariate modelling showed that sediment properties and experimental set-ups had the highest influence on the heavy metal removal indicating that they should be modelled...

  8. Kinetics of electrodialytic extraction of Pb and soil cations from a slurry of contaminated soil fines

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Ferreira, Célia;

    2006-01-01

    The objective of this work was to investigate the kinetics of Pb removal from soil-fines during electrodialytic remediation in suspension, and study the simultaneous dissolution of common soil cations (Al, Ca, Fe, Mg, Mn, Na and K). This was done to evaluate the possibilities within control......-removal was obtained. During the first phase dissolution of carbonates was the prevailing process, resulting in a corresponding loss of soil-mass. During this phase, the investigated ions accounted for the major current transfer, while, as remediation proceeded hydrogen-ions increasingly dominated the transfer. During...

  9. Regressional modeling of electrodialytic removal of Cu, Cr and As from CCA treated timber waste

    DEFF Research Database (Denmark)

    Moreira, E.E.; Ribeiro, Alexandra B.; Mateus, Eduardo;

    2005-01-01

    Waste of wood treated with chromated copper arsenate (CCA) is expected to increase in volume over the next decades. Alternative disposal options to landfilling are becoming more attractive to study, especially those that promote re-use. The authors have studied and modeled the electrodialytic (ED......) removal of Cu, Cr and As from CCA treated timber waste. The method uses a low-level direct current as the cleaning agent, combining the electrokinetic movement of ions in the matrix with the principle of electrodialysis. The technique was tested in eight experiments using a laboratory cell on sawdust...

  10. Multivariate methods for evaluating the efficiency of electrodialytic removal of heavy metals from polluted harbour sediments

    DEFF Research Database (Denmark)

    Pedersen, Kristine Bondo; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2015-01-01

    Chemometrics was used to develop a multivariate model based on 46 previously reported electrodialytic remediation experiments (EDR) of five different harbour sediments. The model predicted final concentrations of Cd, Cu, Pb and Zn as a function of current density, remediation time, stirring rate......-up levels were met in four out of five experiments. The clean-up levels were better than predicted by the model, which could hence be used for predicting an approximate remediation strategy; the modelling power will however improve with more data included. (C) 2014 Elsevier B.V. All rights reserved....

  11. Preliminary treatment of MSW fly ash as a way of improving electrodialytic remediation

    DEFF Research Database (Denmark)

    Ferreira, Célia Maria Dias; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2008-01-01

    In the current work electrodialytic remediation (EDR) was applied to remove heavy metals from municipal solid waste (MSW) fly ash, a hazardous waste collected during flue gas treatment. Tests were conducted to evaluate if EDR could be improved by introducing a preliminary treatment in which very ...... to the fly ash. It was seen that at the end metals are mainly found in the strongly bonded and residual phases. This indicates that the combined treatment (washing + EDR) is successful in reducing the environmental risk posed by fly ash....

  12. Electrodialytic remediation of suspended soil – Comparison of two different soil fractions

    DEFF Research Database (Denmark)

    Sun, Tian Ran; Ottosen, Lisbeth M.; Jensen, Pernille Erland;

    2012-01-01

    Electrodialytic remediation (EDR) can be used for removal of heavy metals from suspended soil, which allows for the soil remediation to be a continuous process. The present paper focused on the processing parameters for remediation of a soil polluted with Cu and As from wood preservation. Six...... electrodialytic treatments lasting from 5 to 22 days with different liquid to solid ratio (L/S) and current intensity were conducted. Among treatments, the highest removal was obtained from the soil fines with 5mA current at L/S 3.5 after 22 days where 96% of Cu and 64% of As were removed. Comparing the removal...... from the original soil and the soil fines in experiments with identical charge transportation, higher removal efficiency was observed from the soil fines. Constant current with 5mA could be maintained at L/S 3.5 for the soil fines while not for the original soil. Doubling current to 10mA could...

  13. Enhanced Eryptosis Following Exposure to Carnosic Acid

    Directory of Open Access Journals (Sweden)

    Katja Stockinger

    2015-11-01

    Full Text Available Background/Aims: The phenolic abietane diterpene component of rosemary and sage, carnosic acid, may either induce or inhibit apoptosis of nucleated cells. The mechanisms involved in the effects of carnosic acid include altered mitochondrial function and gene expression. Human erythrocytes lack mitochondria and nuclei but are nevertheless able to enter suicidal death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Cellular mechanisms involved in the stimulation of eryptosis include oxidative stress, increase of cytosolic Ca2+ activity ([Ca2+]i, and ceramide formation. The present study explored, whether and how carnosic acid induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence and ceramide abundance utilizing specific antibodies. Results: A 48 hours exposure of human erythrocytes to carnosic acid significantly increased the percentage of annexin-V-binding cells (2.5 µg/ml, significantly decreased forward scatter (10 µg/ml, significantly increased Fluo3 fluorescence (10 µg/ml, significantly increased ceramide abundance (10 µg/ml, significantly increased hemolysis (10 µg/ml, but significantly decreased DCFDA fluorescence (10 µg/ml. The effect of carnosic acid on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusion: Carnosic acid triggers cell shrinkage and phospholipid scrambling of the human erythrocyte cell membrane, an effect paralleled by and/or in part due to Ca2+ entry and increased ceramide abundance.

  14. Enhanced Acid/Base Catalysis in High Temperature Liquid Water

    Institute of Scientific and Technical Information of China (English)

    Xiu Yang LU; Qi JING; Zhun LI; Lei YUAN; Fei GAO; Xin LIU

    2006-01-01

    Two novel and environmentally benign solvent systems, organic acids-enriched high temperature liquid water (HTLW) and NH3-enriched HTLW, were developed, which can enhance the reaction rate of acid/base-catalyzed organic reactions in HTLW. We investigated the decomposition of fructose in organic acids-enriched HTLW, hydrolysis of cinnamaldehyde and aldol condensation of phenylaldehyde with acetaldehyde in NH3-enriched HTLW. The experimental results demonstrated that organic acids-enriched or NH3-enriched HTLW can greatly accelerate acid/base-catalyzed organic reactions in HTLW.

  15. Trehalose accumulation enhances tolerance of Saccharomyces cerevisiae to acetic acid.

    Science.gov (United States)

    Yoshiyama, Yoko; Tanaka, Koichi; Yoshiyama, Kohei; Hibi, Makoto; Ogawa, Jun; Shima, Jun

    2015-02-01

    Trehalose confers protection against various environmental stresses on yeast cells. In this study, trehalase gene deletion mutants that accumulate trehalose at high levels showed significant stress tolerance to acetic acid. The enhancement of trehalose accumulation can thus be considered a target in the breeding of acetic acid-tolerant yeast strains.

  16. Enhancing charge storage of conjugated polymer electrodes with phenolic acids

    Science.gov (United States)

    Wagner, Michal; Rębiś, Tomasz; Inganäs, Olle

    2016-01-01

    We here present studies of electrochemical doping of poly(1-aminoanthraquinone) (PAAQ) films with three structurally different phenolic acids. The examined phenolic acids (sinapic, ferulic and syringic acid) were selected due to their resemblance to redox active groups, which can be found in lignin. The outstanding electrochemical stability of PAAQ films synthesized for this work enabled extensive cycling of phenolic acid-doped PAAQ films. Potentiodynamic and charge-discharge studies revealed that phenolic acid-doped PAAQ films exhibited enhanced capacitance in comparison to undoped PAAQ films, together with appearance of redox activity characteristics specific for each dopant. Electrochemical kinetic studies performed on microelectrodes affirmed the fast electron transfer for hydroquinone-to-quinone reactions with these phenolic compounds. These results imply the potential application of phenolic acids in cheap and degradable energy storage devices.

  17. Metabolic engineering as a tool for enhanced lactic acid production.

    Science.gov (United States)

    Upadhyaya, Bikram P; DeVeaux, Linda C; Christopher, Lew P

    2014-12-01

    Metabolic engineering is a powerful biotechnological tool that finds, among others, increased use in constructing microbial strains for higher lactic acid productivity, lower costs and reduced pollution. Engineering the metabolic pathways has concentrated on improving the lactic acid fermentation parameters, enhancing the acid tolerance of production organisms and their abilities to utilize a broad range of substrates, including fermentable biomass-derived sugars. Recent efforts have focused on metabolic engineering of lactic acid bacteria as they produce high yields and have a small genome size that facilitates their genetic manipulation. We summarize here the current trends in metabolic engineering techniques and strategies for manipulating lactic acid producing organisms developed to address and overcome major challenges in the lactic acid production process.

  18. Fabrication and evaluation of an electrodialytic carbonate eluent generator for ion chromatography.

    Science.gov (United States)

    Shen, Guobin; Lu, Yifei; Chen, Feifei; Zhang, Feifang; Yang, Bingcheng

    2016-10-01

    An electrodialytic potassium carbonate eluent generator and its associated potassium bicarbonate eluent generator have been fabricated for ion chromatography (IC). The device can withstand high backpressure up to ∼32MPa and no observable leakage under such pressure is found during 2h. In the range of 0-13.7mM, potassium carbonate concentration can be generated linearly with the applied current with a slope that is essentially Faradaic. At least 10mM potassium carbonate can be online changed into 10mM potassium bicarbonate via a potassium bicarbonate eluent generator, which offers an easy way to manipulate the separation selectivity. When coupled with IC system, the device demonstrated good reproducibility indicated by less than 0.52% of the relative standard deviation of the retention times.

  19. Improvements in ion reflux: An electrodialytic eluent generation and suppression device for ion chromatography.

    Science.gov (United States)

    Elkin, Kyle; Riviello, John; Small, Hamish

    2015-07-17

    This work describes a membrane based electrodialytic ion reflux device (IRD), which uses water as the pumped phase and integrates isocratic and gradient eluent generation and suppression. The current design incorporates several ion exchange membranes to create discrete chambers for suppression and eluent generation, while isolating the electrodes from the analytical stream. A small volume of recycled water can be used as the pumped phase while continuously refluxing the eluent ions. This current design permits electronically controlled eluent generation of at least 16.4μeq KOHmin(-1), while maintaining low suppressed background conductivity (<0.5μS/cm). The device was operated in gradient or isocratic mode continuously for up to 6 weeks. During this period, over 500 gradient and isocratic injections were performed, showing peak retention time precision below 1.5% RSD.

  20. Electrodialytic remediation of fly ash from co-combustion of wood and straw

    DEFF Research Database (Denmark)

    Chen, Wan; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2015-01-01

    The heavy metal content in fly ash from biomass combustion, such as straw, wood and sludge, often needs reducing before the ash can be used as fertilizer for agricultural land or as a component in the production of construction materials. In this study, fly ash from a boiler fueled with wood chips...... and straw was treated either by electrodialytic remediation (EDR) directly or by a combination of EDR and pre-wash with distilled water to investigate the possibilities of reducing the heavy metal content and reusing nutrients as fertilizer and bulk material in construction materials. Different experimental...... set-ups were tested for EDR treatment primarily of Cd and Pb as well as of Cu and Zn. Elemental contents such as K, P and Ni were compared in ash samples before and after treatment. The results showed that pre-washing caused an increase in total concentrations of most heavy metals because the highly...

  1. Electrodialytic remediation of CCA-treated waste wood in a 2 m3 pilot plant

    DEFF Research Database (Denmark)

    Christensen, Iben Vernegren; Pedersen, Anne Juul; Ottosen, Lisbeth M.;

    2006-01-01

    Waste wood that has been treated with chromated-copper-arsenate (CCA) poses a potential environmental problem due to the content of copper, chromium and arsenic. A pilot plant for electrodialytic remediation of up to 2 m3 wood has been designed and tested and the results are presented here. Several...... fractions. The best remediation efficiency was obtained in an experiment with an electrode distance of 60 cm, and 100 kg wood chips. In this experiment 87% copper, 81% chromium and > 95% arsenic were removed. One other experiment was also analysed for arsenic. In this experiment the distance between...... the working electrodes was 1.5 m and here 95% As was removed. The results showed that arsenic may be the easiest removable of the copper, chromium and arsenic investigated here. This is very encouraging since arsenic is the CCA components of most environmental concern....

  2. Characterization and electrodialytic treatment of wood combustion fly ash for removal of cadmium

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul

    2003-01-01

    Due to a high content of macronutrients and a potential liming capacity, recycling of ashes from biomass combustion to agricultural fields as fertilisers and/or for soil improvement is considered in Denmark and other countries utilising biomass as an energy source. However, the fly ash fractions......-for the aim of recycling-was described. Initial characterisation of the experimental ash showed that the Cd content exceeded the limiting values for agricultural use and therefore needed treatment before being recycled. The pH in the ash was very high (13.3), and the Cd was not soluble at these alkaline...... conditions. However, significant amounts of Cd could be extracted at neutral to alkaline conditions using an ammonium citrate solution as a desorption agent.Electrodialytic remediation experiments showed that, under optimised remediation conditions using a mixture of ammonium citrate (0.25M) and NH"3 (1...

  3. Electrodialytic removal of Cd from straw ash in a pilot plant

    DEFF Research Database (Denmark)

    Lima, Ana Teresa; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2008-01-01

    Ashes from biomass combustion contain many macro and micro nutrients and its reuse in agricultural fields could be beneficial. In the case of straw ash, however, the content of Cd is often too high for the ash to be utilized this way. In Denmark the limiting concentration for spreading the ash...... in agricultural land is 5.0 mg Cd/kg and in order to utilize the nutrients in the straw ash it is necessary to decrease the Cd content to meet this limiting concentration. It has been previously shown, at a laboratory scale, that the Cd concentration can successfully be decreased by an electrodialytic method...... this concentration still exceeds the limiting concentration, valuable experience concerning the practical operation through scale-up was obtained. In addition, the experiments are a good basis for further scale-up and optimization of the process for improved Cd removal to meet the requirements. A very important...

  4. Electrodialytic Remediation of Different Heavy Metal-Polluted Soils in Suspension

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2013-01-01

    Electrokinetic remediation of heavy metal-polluted soil faces different challenges in relation to implementation. One challenge is to cope with the nonlinear and transient geochemical changes in the soil and another is to increase the remediation rate. Both these challenges are met when treating...... is necessary to meet the goal. The good results were obtained even without optimization of processing parameters, but the investigation underlined that the optimal parameters are highly soil and pollution specific....... the soil in a suspension in an electrodialytic cell. The soil suspension is stirred and uniform during treatment. Previously, it has been shown that a faster remediation can be obtained when remediating a stirred soil suspension compared to a stationary water saturated soil (all other parameters the same...

  5. Electrodialytic remediation of air pollution control residues in bench scale

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ferreira, Celia; Hansen, Henrik K.

    2008-01-01

    Air pollution control (APC) residue from municipal solid waste incineration (MSWI) is considered a hazardous waste due to its alkalinity and high content of salts and mobile heavy metals. Various solutions for the handling of APC-residue exist in different regions; however, most commercial....... A system resembling conventional electrodialysis was designed and adjusted to fit the high solids content feed solution (10% APC residue, 90% water). Experiments were made in bench scale with raw residue (natural pH > 12), water pre-residue (natural pH > 12), acid pre-washed residue (pH 10), and acid......). Between 57 and 83% of the APC residue was dissolved during treatment. The highest dissolution was seen for acid treated residue and the lowest for water pre-washed residue....

  6. The influence of electrodialytic remediation on dioxin (PCDD/PCDF) levels in fly ash and air pollution control residues.

    Science.gov (United States)

    Dias-Ferreira, Celia; Kirkelund, Gunvor M; Jensen, Pernille E

    2016-04-01

    Fly ash and Air Pollution Control (APC) residues collected from three municipal solid waste incinerators in Denmark and Greenland were treated by electrodialytic remediation at pilot scale for 8-10 h. This work presents for the first time the effect of electrodialytic treatment on polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF), and how these levels impact on the valorization options for fly ash and APC residue. PCDD/PCDF levels in the original residues ranged between 4.85 and 197 ng g(-1), being higher for the electrostatic precipitator fly ash. The toxic equivalent (TEQ) varied ten fold, ranging 0.18-2.0 ng g(-1) I-TEQ, with penta and hexa-homologs being most significant for toxicity. After the electrodialytic treatment PCDD/PCDF levels increased in the residues (between 1.4 and 2.0 times). This does not mean PCDD/PCDF were synthesized, but else that soluble materials dissolve, leaving behind the non-water soluble compounds, such as PCDD/PCDF. According to the Basel Convention, PCDD/PCDF levels in these materials is low (ash and APC residue could eventually be valorized, for instance as construction material, provided end-of-waste criteria are set and that a risk assessment of individual options is carried out, including the end-of-life stage when the materials become waste again.

  7. Acid tolerance response (ATR) of microbial communities during the enhanced biohydrogen process via cascade acid stress.

    Science.gov (United States)

    Lin, Xiaoqin; Xia, Yan; Yan, Qun; Shen, Wei; Zhao, Mingxing

    2014-03-01

    Enhanced biohydrogen production via cascade acid stress on microbial communities, structure patterns of the microbial communities revealed by PLFAs, and the succession of biohydrogen related species against cascade acid stress were all investigated. It was found that hydrogen production could be improved from 48.7 to 79.4mL/gVS after cascade acid stress. In addition, the Gram negative (G(-)) bacteria were found to be more tolerant to organic acids than those of the Gram positive (G(+)) bacteria, regardless of the dominance of G(+) bacteria within the microbial communities. Moreover, Clostridium butyricum, Clostridium aciditolerans and Azospira oryzae, were proved to be enriched, and then might play indispensable roles for the enhanced biohydrogen production after cascade acid stress, as which were responsible for the biohydrogen accumulation, acid tolerance and nitrogen removal, respectively.

  8. An Effective Acid Combination for Enhanced Properties and Corrosion Control of Acidizing Sandstone Formation

    Science.gov (United States)

    Umer Shafiq, Mian; Khaled Ben Mahmud, Hisham

    2016-03-01

    To fulfill the demand of the world energy, more technologies to enhance the recovery of oil production are being developed. Sandstone acidizing has been introduced and it acts as one of the important means to increase oil and gas production. Sandstone acidizing operation generally uses acids, which create or enlarge the flow channels of formation around the wellbore. In sandstone matrix acidizing, acids are injected into the formation at a pressure below the formation fracturing pressure, in which the injected acids react with mineral particles that may restrict the flow of hydrocarbons. Most common combination is Hydrofluoric Acid - Hydrochloric with concentration (3% HF - 12% HCl) known as mud acid. But there are some problems associated with the use of mud acid i.e., corrosion, precipitation. In this paper several new combinations of acids were experimentally screened to identify the most effective combination. The combinations used consist of fluoboric, phosphoric, formic and hydrofluoric acids. Cores were allowed to react with these combinations and results are compared with the mud acid. The parameters, which are analyzed, are Improved Permeability Ratio, strength and mineralogy. The analysis showed that the new acid combination has the potential to be used in sandstone acidizing.

  9. Polypeptides having cellulolytic enhancing activity and nucleic acids encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kimberly; Harris, Paul; Zaretsky, Elizabeth; Re, Edward; Vlasenko, Elena; McFarland, Keith; Lopez de Leon, Alfredo

    2016-08-09

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

  10. Polypeptides having cellulolytic enhancing activity and nucleic acids encoding same

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kimberly; Harris, Paul; Zaretsky, Elizabeth; Re, Edward; Vlasenko, Elena; McFarland, Keith; Lopez de Leon, Alfredo

    2014-09-30

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

  11. Electrodialytic remediation of harbour sediment in suspension - Evaluation of effects induced by changes in stirring velocity and current density on heavy metal removal and pH

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2009-01-01

    Electrodialytic remediation was used to remove heavy metals from a suspension of dredged harbour sediment. The studied metals Cu, Pb, Zn and Cd are normally strongly bound in anoxic sediment. Six electrodialytic laboratory remediation experiments were made, lasting 14 days and under oxic conditions....... The influence on the metal removal was investigated by changing current densities and stirring velocity of the sediment suspension. Using a current density of 1.0 mA/cm2 gave the highest metal removal. The sediment suspension was partly oxidised when mixed into a suspension for the electrodialytic remediation...... experiments and was further oxidised during the experiments. Even at low stirring velocities, oxic conditions were obtained. The metal removal was dependent on the achieved pH in the sediment and the highest metal removal and corresponding low pH was obtained by using a current density of 1.0 mA/cm2...

  12. Electroporation-enhanced delivery of nucleic acid vaccines.

    Science.gov (United States)

    Broderick, Kate E; Humeau, Laurent M

    2015-02-01

    The naked delivery of nucleic acid vaccines is notoriously inefficient, and an enabling delivery technology is required to direct efficiently these constructs intracellularly. A delivery technology capable of enhancing nucleic acid uptake in both cells in tissues and in culture is electroporation (EP). EP is a physical delivery mechanism that increases the permeability of mammalian cell membranes and allows the trafficking of large macromolecules into the cell. EP has now been used extensively in the clinic and been shown to be an effective method to increase both the uptake of the construct and the breadth and magnitude of the resulting immune responses. Excitingly, 2014 saw the announcement of the first EP-enhanced DNA vaccine Phase II trial demonstrating clinical efficacy. This review seeks to introduce the reader to EP as a technology to enhance the delivery of DNA and RNA vaccines and highlight several published clinical trials using this delivery modality.

  13. Enhanced formic acid oxidation on Cu-Pd nanoparticles

    Science.gov (United States)

    Dai, Lin; Zou, Shouzhong

    Developing catalysts with high activity and high resistance to surface poisoning remains a challenge in direct formic acid fuel cell research. In this work, copper-palladium nanoparticles were formed through a galvanic replacement process. After electrochemically selective dissolution of surface Cu, Pd-enriched Cu-Pd nanoparticles were formed. These particles exhibit much higher formic acid oxidation activities than that on pure Pd nanoparticles, and they are much more resistant to the surface poisoning. Possible mechanisms of catalytic activity enhancement are briefly discussed.

  14. Nucleic acid molecules conferring enhanced ethanol tolerance and microorganisms having enhanced tolerance to ethanol

    Science.gov (United States)

    Brown, Steven; Guss, Adam; Yang, Shihui; Karpinets, Tatiana; Lynd, Lee; Shao, Xiongjun

    2014-01-14

    The present invention provides isolated nucleic acid molecules which encode a mutant acetaldehyde-CoA/alcohol dehydrogenase or mutant alcohol dehydrogenase and confer enhanced tolerance to ethanol. The invention also provides related expression vectors, genetically engineered microorganisms having enhanced tolerance to ethanol, as well as methods of making and using such genetically modified microorganisms for production of biofuels based on fermentation of biomass materials.

  15. Lewis acidity enhancement of triarylborane by appended phosphine oxide groups.

    Science.gov (United States)

    Kwak, Jaewoo; Nghia, Nguyen Van; Lee, Junseong; Kim, Hyoseok; Park, Myung Hwan; Lee, Min Hyung

    2015-03-14

    A series of mono-, di-, and tri-phosphine oxide substituted triarylboranes, Mes2BAr (1), MesBAr2 (2), and BAr3 (3) (Ar = 4-(Ph2PO)-2,6-Me2-C6H2) were prepared to investigate the effect of a phosphine oxide group (Ph2PO) on Lewis acidity enhancement of triarylboranes. The X-ray crystal structure of 3 revealed peripheral decoration of Ph2PO groups with a C3-axis perpendicular to the trigonal boron center. UV/Vis absorption and PL spectra indicated a significant contribution of π(Mes or phenylene) → pπ(B) charge transfer in the lower-energy electronic transition. The reduction potential measured by cyclic voltammetry showed apparent LUMO stabilization by introduction of phosphine oxide groups, the extent of which gradually increased with the increasing number of phosphine oxide groups. Lewis acidity enhancement was also supported by the gradual increase in fluoride ion affinity in the order 3 > 2 > 1. Theoretical calculations suggest that introduction of a Ph2PO group into a triarylborane significantly enhances the Lewis acidity of the boron center via an inductive electron-withdrawing effect and this effect is additive for multiple phosphine oxide groups.

  16. Enhance decarboxylation reaction of carboxylic acids in clay minerals

    Energy Technology Data Exchange (ETDEWEB)

    Negron-Mendoza, A.; Ramos, S.; Albarran, G. [Instituto de Ciencias y Artes, Chiapas (Mexico). Escuela de Biologia

    1995-10-01

    Clay minerals are important constituents of the Earth`s crust. These minerals catalyze reactions in several ways: by energy transfer processes, redox reactions, stabilization of intermediates and by Broensted or Lewis acidity behavior. Important set of organic reactions can be improved in the precedence of clay minerals. Besides the properties of clays to catalyze chemical reactions, it is possible to enhance some of its reactions by using ionizing radiation. The phenomenon of radiation-induced catalysis may be connected with ionizing process in the solid and with the trapped non-equilibrium charge carriers. In this paper we are reporting the decarboxylation reaction of carboxylic acids catalyzed by clay and by irradiation of the system acid-clay. We studied the behaviour of several carboxylic acids and analyzed them by gas chromatography, X-ray and infrared spectroscopy. The results showed that decarboxylation of the target compound is the dominating pathway. The reaction is enhanced by gamma radiation in several orders of magnitude. (author).

  17. Exploring unsaturated fatty acid cholesteryl esters as transdermal permeation enhancers.

    Science.gov (United States)

    Rambharose, Sanjeev; Kalhapure, Rahul S; Jadhav, Mahantesh; Govender, Thirumala

    2017-04-01

    The intrinsic protective barrier property of skin, one of the major challenges in the design of transdermal drug delivery systems, can be overcome through the use of chemical permeation enhancers (CPEs). Herein, we explore the potential of unsaturated fatty acid (UFA) esters of cholesterol (Chol) viz., oleate, linoleate and linolenate, as transdermal CPEs using tenofovir (TNF) as a model drug. All Chol UFA esters at 1% w/w were found to be more effective enhancers when compared to their respective parent fatty acids (FAs) and saturated FA counterparts. Cholesteryl linolenate (Chol-LLA) showed the most superior performance (enhancement ratio (ER) = 3.71). The greatest ER for Chol-LLA (5.93) was achieved at a concentration of 2% w/w. The histomorphological and transepithelial electrical resistance (TEER) evaluations supported the results of the permeability studies. These findings showed no significant loss in the integrity of the epidermis, with drug and enhancer treatment having temporary effects on the barrier property of the epidermis. Chol UFA esters can therefore be considered as new CPEs for exploitation in topical formulations for various classes of drugs.

  18. Replacement of 5% of OPC by fly ash and APC residues from MSWI with electrodialytic pre-treatment

    DEFF Research Database (Denmark)

    Magro, Cátia; Kirkelund, Gunvor Marie; Guedes, Paula

    2016-01-01

    Fly ash (FA) and air pollution control (APC) residues are waste products from Municipal Solid Waste Incineration (MSWI). They are classified as hazardous waste due to the content of leachable heavy metals (HM), salts and/or dioxins. An electrodialytic (ED) process was applied to FA and APC residues...... leaching of HM and the Cl content. The compressive tests presented comparable values to the reference mortars. This study suggests that the characteristics of FA and APC residues from MSWI after pre-treatment allows them to be reused in building materials, giving a new edge to waste management....

  19. Experimental and modeling of the electrodialytic and dialytic treatment of a fly ash containing Cd, Cu and Pb

    DEFF Research Database (Denmark)

    Lima, A.T.; Ribeiro, A.B.; Rodriguez-Maroto, J.M.

    2010-01-01

    A one-dimensional model is developed for simulating the electrodialytic and dialytic treatment of a fly ash containing cadmium, copper and lead. Two experimental systems have been used, a column of ash and a stirred ash suspension. The movement of Cd, Cu and Pb has been modeled taking into account...... ionic species in the system, H+ and OH-, proceeding of the electrolysis at the electrodes, Ca2+, CO3 (=), SO4 (=), etc. proceeding from the ash and Na+ and NO3 (-), or citrate and ammonium ions incorporated as electrolyte solutions and/or as agent solution during the ash treatment. The simulation also...

  20. Electrodialytic removal of Cu, Zn, Pb, and Cd from harbor sediment: Influence of changing experimental conditions

    DEFF Research Database (Denmark)

    Nystrøm, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Electrodialytic remediation (EDR) was used to remove Cu, Zn, Pb, and Cd from contaminated harbor sediment. Extraction experiments were made prior to EDR, and the metal desorption was pH dependent but not liquid-to-solid ratio (L/S) dependent. The desorption order was Cd $GRT Zn $GRT Pb $GRT Cu...... for the removal of Cu, Zn, and Pb, probably due to oxidation of the sediments during stirring. Contrary, Cd removal was lower in the wet sediment as compared to the air-dried. The heavy metal removal was influenced by higher current strengths and varying L/S ratios. The highest removal obtained...... was in an experiment with dry sediment (L/S 8) and a 70 mA applied current that lasted 14 days. These experimental conditions were thereafter used to remediate more strongly contaminated sediments. Regardless of the initial heavy metal concentrations in the sediments, 67-87% Cu, 79-98% Cd, 90-97% Zn, and 91-96% Pb...

  1. Multivariate methods for evaluating the efficiency of electrodialytic removal of heavy metals from polluted harbour sediments.

    Science.gov (United States)

    Pedersen, Kristine Bondo; Kirkelund, Gunvor M; Ottosen, Lisbeth M; Jensen, Pernille E; Lejon, Tore

    2015-01-01

    Chemometrics was used to develop a multivariate model based on 46 previously reported electrodialytic remediation experiments (EDR) of five different harbour sediments. The model predicted final concentrations of Cd, Cu, Pb and Zn as a function of current density, remediation time, stirring rate, dry/wet sediment, cell set-up as well as sediment properties. Evaluation of the model showed that remediation time and current density had the highest comparative influence on the clean-up levels. Individual models for each heavy metal showed variance in the variable importance, indicating that the targeted heavy metals were bound to different sediment fractions. Based on the results, a PLS model was used to design five new EDR experiments of a sixth sediment to achieve specified clean-up levels of Cu and Pb. The removal efficiencies were up to 82% for Cu and 87% for Pb and the targeted clean-up levels were met in four out of five experiments. The clean-up levels were better than predicted by the model, which could hence be used for predicting an approximate remediation strategy; the modelling power will however improve with more data included.

  2. Effects from different types of construction refuse in the soil on electrodialytic remediation

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Eriksson, Thomas; Hansen, Henrik K.

    2002-01-01

    at the surface of the screw causing pH changes in the soil. Two types of refuse with ionic conducting properties were placed within the test cell, a piece of brick and concrete. The brick did not influence the Cu removal from the soil to a high extent, but it was seen that during the remediation the Cu...... of different sorts of construction refuse on electrodialytic soil remediation was investigated in laboratory cells. An insulator, a stone, resulted in an uneven Cu removal in the close vicinity of the stone itself. An electric conductive screw disturbed the Cu removal due to the redox reactions occurring...... concentration in the brick itself increased. In the case of concrete the Cu mobilized from the soil was simply found to adsorb very strongly to the concrete and thus the Cu could not be removed from the soil and the concrete as a whole. Furthermore, the removal of Cu in the soil next to the concrete was quite...

  3. Study of Valproic Acid-Enhanced Hepatocyte Steatosis

    Directory of Open Access Journals (Sweden)

    Renin Chang

    2016-01-01

    Full Text Available Valproic acid (VPA is one of the most widely used antiepilepsy drugs. However, several side effects, including weight gain and fatty liver, have been reported in patients following VPA treatment. In this study, we explored the molecular mechanisms of VPA-induced hepatic steatosis using FL83B cell line-based in vitro model. Using fluorescent lipid staining technique, we found that VPA enhanced oleic acid- (OLA- induced lipid accumulation in a dose-dependent manner in hepatocytes; this may be due to upregulated lipid uptake, triacylglycerol (TAG synthesis, and lipid droplet formation. Real-time PCR results showed that, following VPA treatment, the expression levels of genes encoding cluster of differentiation 36 (Cd36, low-density lipoprotein receptor-related protein 1 (Lrp1, diacylglycerol acyltransferase 2 (Dgat2, and perilipin 2 (Plin2 were increased, that of carnitine palmitoyltransferase I a (Cpt1a was not affected, and those of acetyl-Co A carboxylase α (Acca and fatty acid synthase (Fasn were decreased. Furthermore, using immunofluorescence staining and flow cytometry analyses, we found that VPA also induced peroxisome proliferator-activated receptor γ (PPARγ nuclear translocation and increased levels of cell-surface CD36. Based on these results, we propose that VPA may enhance OLA-induced hepatocyte steatosis through the upregulation of PPARγ- and CD36-dependent lipid uptake, TAG synthesis, and lipid droplet formation.

  4. Effect of Enhancing Urea-Humic Acid Mixture with Refined Acid Sulphate Soil

    Directory of Open Access Journals (Sweden)

    Mohd T.M. Yusuff

    2009-01-01

    Full Text Available Problem statement: Acid Sulphate Soil (ASS is a problem soil partly because of its high acidity. This low pH could be exploited to reduce ammonia loss from urea by reducing soil microsite pH. The use Humic Acid (HA to control ammonia loss from urea has been reported but the cost of this material is high. This laboratory study compared the effect of enhancing urea-humic acid mixtures with acid sulphate soil on NH3 loss, pH, exchangeable ammonium and available nitrate contents. Approach: Humic acid, acid sulfate soil and soil used in the incubation study were analyzed for selected soil physical-chemical properties using standard procedures. Urea-HA-ASS mixtures were prepared and ammonia volatilization of the mixtures was evaluated by the closed-dynamic air flow system. The treatments were evaluated in a randomized complete block design with 3 replications. Standard procedures were used to determine ammonia loss, soil pH, exchangeable ammonium and available nitrate at 22 days of incubation. Data obtained were analyzed using analysis of variance and Duncan's test using Statistical Analysis System (SAS version 9.2. Results: Urea amended with 0.75 g ASS significantly reduced ammonia volatilization. Although the use of appropriate amount of acid sulphate soil to control ammonia loss is possible, excessive use of this material is not recommended because of Fe in it. Conclusion: Urea amended with 0.75 g ASS reduced ammonia.

  5. Enhancing and targeting nucleic acid delivery by magnetic force.

    Science.gov (United States)

    Plank, Christian; Anton, Martina; Rudolph, Carsten; Rosenecker, Joseph; Krötz, Florian

    2003-08-01

    Insufficient contact of inherently highly active nucleic acid delivery systems with target cells is a primary reason for their often observed limited efficacy. Physical methods of targeting can overcome this limitation and reduce the risk of undesired side effects due to non-target site delivery. The authors and others have developed a novel means of physical targeting, exploiting magnetic force acting on nucleic acid vectors associated with magnetic particles in order to mediate the rapid contact of vectors with target cells. Here, the principles of magnetic drug and nucleic acid delivery are reviewed, and the facts and potentials of the technique for research and therapeutic applications are discussed. Magnetically enhanced nucleic acid delivery - magnetofection - is universally applicable to viral and non-viral vectors, is extraordinarily rapid, simple and yields saturation level transfection at low dose in vitro. The method is useful for site-specific vector targeting in vivo. Exploiting the full potential of the technique requires an interdisciplinary research effort in magnetic field physics, magnetic particle chemistry, pharmaceutical formulation and medical application.

  6. Fatty acid conjugation enhances the activities of antimicrobial peptides.

    Science.gov (United States)

    Li, Zhining; Yuan, Penghui; Xing, Meng; He, Zhumei; Dong, Chuanfu; Cao, Yongchang; Liu, Qiuyun

    2013-04-01

    Antimicrobial peptides are small molecules that play a crucial role in innate immunity in multi-cellular organisms, and usually expressed and secreted constantly at basal levels to prevent infection, but local production can be augmented upon an infection. The clock is ticking as rising antibiotic abuse has led to the emergence of many drug resistance bacteria. Due to their broad spectrum antibiotic and antifungal activities as well as anti-viral and anti-tumor activities, efforts are being made to develop antimicrobial peptides into future microbial agents. This article describes some of the recent patents on antimicrobial peptides with fatty acid conjugation. Potency and selectivity of antimicrobial peptide can be modulated with fatty acid tails of variable length. Interaction between membranes and antimicrobial peptides was affected by fatty acid conjugation. At concentrations above the critical miscelle concentration (CMC), propensity of solution selfassembly hampered binding of the peptide to cell membranes. Overall, fatty acid conjugation has enhanced the activities of antimicrobial peptides, and occasionally it rendered inactive antimicrobial peptides to be bioactive. Antimicrobial peptides can not only be used as medicine but also as food additives.

  7. Transcutaneous delivery of levodopa: enhancement by fatty acid synthesis inhibition.

    Science.gov (United States)

    Babita, Kumar; Tiwary, Ashok K

    2005-01-01

    The present investigation aimed at evaluating the role of fatty acid synthesis inhibition in enhancing transcutaneous delivery of levodopa (LD). Rat epidermis was treated with ethanol and various doses of cerulenin (an inhibitor of fatty acid synthase enzyme system) for reducing the normal level of fatty acids. Calcium chloride (0.1 mM) and/or verapamil (1 microM) were coapplied to cerulenin treated skin in order to modulate duration of epidermal perturbation. These treated skin portions were used for estimation of altered triglyceride content (an indicator of fatty acid synthesis), differential scanning calorimetry (DSC) analysis, and in vitro permeation of LD. Plasma concentration of LD was monitored in rats following topical application of various transdermal formulations. Application of cerulenin (0.1 or 0.15 mM/7 cm(2)) to viable rat skin inhibited approximately 60% triglyceride synthesis with respect to control at 2 h. Coapplication of calcium chloride (0.1 mM) significantly increased this inhibition, whereas verapamil application reduced this effect. The decrease in triglyceride content reduced the enthalpy of the lipid endothermic transition. The in vitro permeation of LD was enhanced 3-fold across skin excised after treatment with cerulenin. LD did not permeate across normal skin. The effective plasma concentration (C(eff)) of LD was achieved within 3 h and maintained till 10 h by a single topical application of a carbidopa-levodopa combination (1:4) to ethanol-perturbed cerulenin-treated skin. Coapplication of calcium chloride reduced the time lag to achieve C(eff) to 2 h and maintained it till 24 h. A single transdermal LD (64 mg) patch formulated with calcium chloride (0.1 mM) and cerulenin (0.1 mM) dissolved in a propylene glycol:ethanol (7:3) mixture seems to offer a noninvasive approach for transcutaneous delivery of levodopa.

  8. Pipecolic acid enhances resistance to bacterial infection and primes salicylic acid and nicotine accumulation in tobacco.

    Science.gov (United States)

    Vogel-Adghough, Drissia; Stahl, Elia; Návarová, Hana; Zeier, Juergen

    2013-11-01

    Distinct amino acid metabolic pathways constitute integral parts of the plant immune system. We have recently identified pipecolic acid (Pip), a lysine-derived non-protein amino acid, as a critical regulator of systemic acquired resistance (SAR) and basal immunity to bacterial infection in Arabidopsis thaliana. In Arabidopsis, Pip acts as an endogenous mediator of defense amplification and priming. For instance, Pip conditions plants for effective biosynthesis of the phenolic defense signal salicylic acid (SA), accumulation of the phytoalexin camalexin, and expression of defense-related genes. Here, we show that tobacco plants respond to leaf infection by the compatible bacterial pathogen Pseudomonas syringae pv tabaci (Pstb) with a significant accumulation of several amino acids, including Lys, branched-chain, aromatic, and amide group amino acids. Moreover, Pstb strongly triggers, alongside the biosynthesis of SA and increases in the defensive alkaloid nicotine, the production of the Lys catabolites Pip and α-aminoadipic acid. Exogenous application of Pip to tobacco plants provides significant protection to infection by adapted Pstb or by non-adapted, hypersensitive cell death-inducing P. syringae pv maculicola. Pip thereby primes tobacco for rapid and strong accumulation of SA and nicotine following bacterial infection. Thus, our study indicates that the role of Pip as an amplifier of immune responses is conserved between members of the rosid and asterid groups of eudicot plants and suggests a broad practical applicability for Pip as a natural enhancer of plant disease resistance.

  9. Folic acid induces salicylic acid-dependent immunity in Arabidopsis and enhances susceptibility to Alternaria brassicicola.

    Science.gov (United States)

    Wittek, Finni; Kanawati, Basem; Wenig, Marion; Hoffmann, Thomas; Franz-Oberdorf, Katrin; Schwab, Wilfried; Schmitt-Kopplin, Philippe; Vlot, A Corina

    2015-08-01

    Folates are essential for one-carbon transfer reactions in all organisms and contribute, for example, to de novo DNA synthesis. Here, we detected the folate precursors 7,8-dihydropteroate (DHP) and 4-amino-4-deoxychorismate (ADC) in extracts from Arabidopsis thaliana plants by Fourier transform ion cyclotron resonance-mass spectrometry. The accumulation of DHP, but not ADC, was induced after infection of plants with Pseudomonas syringae delivering the effector protein AvrRpm1. Application of folic acid or the DHP precursor 7,8-dihydroneopterin (DHN) enhanced resistance in Arabidopsis to P. syringae and elevated the transcript accumulation of the salicylic acid (SA) marker gene pathogenesis-related1 in both the treated and systemic untreated leaves. DHN- and folic acid-induced systemic resistance was dependent on SA biosynthesis and signalling. Similar to SA, folic acid application locally enhanced Arabidopsis susceptibility to the necrotrophic fungus Alternaria brassicicola. Together, the data associate the folic acid pathway with innate immunity in Arabidopsis, simultaneously activating local and systemic SA-dependent resistance to P. syringae and suppressing local resistance to A. brassicicola.

  10. Degradation of oil products in a soil from a Russian Barents hot-spot during electrodialytic remediation.

    Science.gov (United States)

    Pedersen, Kristine B; Lejon, Tore; Jensen, Pernille E; Ottosen, Lisbeth M

    2016-01-01

    A highly oil-polluted soil from Krasnoe in North-West Russia was used to investigate the degradation of organic pollutants during electrodialytic remediation. Removal efficiencies were up to 70 % for total hydrocarbons (THC) and up to 65 % for polyaromatic hydrocarbons (PAH). Relatively more of the lighter PAH compounds and THC fractions were degraded. A principal component analysis (PCA) revealed a difference in the distribution of PAH compounds after the remediation. The observed clustering of experiments in the PCA scores plot was assessed to be related to the stirring rate. Multivariate analysis of the experimental settings and final concentrations in the 12 experiments revealed that the stirring rate of the soil suspension was by far the most important parameter for the remediation for both THC and PAH. Light was the second most important variable for PAH and seems to influence degradation. The experimental variables current density and remediation time did not significantly influence the degradation of the organic pollutants. Despite current density not influencing the remediation, there is potential for degrading organic pollutants during electrodialytic removal of heavy metals, as long as a stirred set-up is applied. Depending on remediation objectives, further optimisation may be needed in order to develop efficient remediation strategies.

  11. Investigation of the interaction of polyamidoamine dendrimers with nicotinic acid as solubility enhancer

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective Polyamidoamine(PAMAM) dendrimers enhance the solubility of nicotinic acid. Methods PAMAM dendrimers of generation 1 to 6 were prepared and the effect of pH and concentration of the dendrimers on the solubility enhancement of nicotinic acid was investigated. Results The pH and concentration of the dendrimers influence the solubility enhancement of nicotinic acid. Conclusions Electrostatic interaction between the carboxyl group of the nicotinic acid and the amine groups of the dendrimers is involved.

  12. Salicylic acid enhances Staphylococcus aureus extracellular adhesin protein expression.

    Science.gov (United States)

    Alvarez, Lucía P; Barbagelata, María S; Cheung, Ambrose L; Sordelli, Daniel O; Buzzola, Fernanda R

    2011-11-01

    One of the virulence factors required by Staphylococcus aureus at the early stages of infection is Eap, a secreted adhesin that binds many host proteins and is upregulated by the two-component regulatory system saeRS. The S. aureus Newman strain harbors a mutation in saeS that is thought to be responsible for the high level of Eap expression in this strain. This study was designed to ascertain whether salicylic acid (SAL) affects the expression of Eap and the internalization of S. aureus into epithelial cells. The strain Newman treated with SAL exhibited increased levels of eap transcription and protein expression. Furthermore, SAL treatment increased the eap promoter activity. SAL treatment enhanced Eap expression in the Newman and in other S. aureus strains that do not carry the mutation in saeS. Internalization of S. aureus eap and sae mutants into the MAC-T epithelial cells was significantly decreased compared with the wild-type counterparts. In conclusion, we demonstrated that a low concentration of SAL increased S. aureus Eap expression possibly due to enhancement of sae. SAL may create the conditions for S. aureus persistence in the host, not only by decreasing the capsular polysaccharide expression as shown before, but also by enhancing Eap expression.

  13. Abscisic acid enhances resistance to Alternaria solani in tomato seedlings.

    Science.gov (United States)

    Song, Weiwei; Ma, Xinrong; Tan, Hong; Zhou, Jinyan

    2011-07-01

    The plant hormone abscisic acid (ABA) is an important regulator in many aspects of plant growth and development, as well as stress resistance. Here, we investigated the effects of exogenous ABA application on the interaction between tomato (Solanum lycopersicon L.) and Alternaria solani (early blight). Foliar spraying of 7.58 μM ABA was effective in reducing disease severity in tomato plants. Previously, increased activities of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD) were observed in exogenous ABA-treated tomato leaves. Moreover, these enzyme activities were maintained at higher levels in ABA-pretreated and A. solani challenged tomato plants. Tomato defense genes, such as PR1, β-1, 3-glucanase (GLU), PPO, POD, and superoxide dismutase (SOD), were rapidly and significantly up-regulated by exogenous ABA treatment. Furthermore, a subsequent challenge of ABA-pretreated plants with the pathogen A. solani resulted in higher expression of defense genes, compared to water-treated or A. solani inoculated plants. Therefore, our results suggest that exogenous ABA could enhance disease resistance against A. solani infection in tomato through the activation of defense genes and via the enhancement of defense-related enzymatic activities.

  14. Oleic Acid: Natural variation and potential enhancement in oilseed crops.

    Science.gov (United States)

    Oleic acid is a monounsaturated omega 9 fatty acid (MUFA, C18:1) which can be found in various plant lipids and animal fats. Unlike omega 3 (a-linolenic acid, C18:3) and omega 6 (linoleic acid, C18:2) fatty acids which are essential because they cannot be synthesized by humans and must be obtained f...

  15. Enhancement of neutrophil-mediated killing of Plasmodium falciparum asexual blood forms by fatty acids: importance of fatty acid structure.

    Science.gov (United States)

    Kumaratilake, L M; Ferrante, A; Robinson, B S; Jaeger, T; Poulos, A

    1997-10-01

    Effects of fatty acids on human neutrophil-mediated killing of Plasmodium falciparum asexual blood forms were investigated by using a quantitative radiometric assay. The results showed that the antiparasitic activity of neutrophils can be greatly increased (>threefold) by short-term treatment with fatty acids with 20 to 24 carbon atoms and at least three double bonds. In particular, the n-3 polyenoic fatty acids, eicosapentaenoic and docosahexaenoic acids, and the n-6 fatty acid, arachidonic acid, significantly enhanced neutrophil antiparasitic activity. This effect was >1.5-fold higher than that induced by an optical concentration of the known agonist cytokine tumor necrosis factor alpha (TNF-alpha). At suboptimal concentrations, the combination of arachidonic acid and TNF-alpha caused a synergistic increase in neutrophil-mediated parasite killing. The fatty acid-induced effect was independent of the availability of serum opsonins but dependent on the structure of the fatty acids. The length of the carbon chain, degree of unsaturation, and availability of a free carboxyl group were important determinants of fatty acid activity. The fatty acids which increased neutrophil-mediated killing primed the enhanced superoxide radical generation of neutrophils in response to P. falciparum as detected by chemiluminescence. Scavengers of oxygen radicals significantly reduced the fatty acid-enhanced parasite killing, but cyclooxygenase and lipoxygenase inhibitors had no effect. These findings have identified a new class of immunoenhancers that could be exploited to increase resistance against Plasmodium species.

  16. Lewis acid enhanced switching of the 1,1-dicyanodihydroazulene/vinylheptafulvene photo/thermoswitch

    DEFF Research Database (Denmark)

    Parker, Christian Richard; Tortzen, Christian Gregers; Broman, Søren Lindbæk;

    2011-01-01

    Mild Lewis acids enhance the rate of the thermal conversion of vinylheptafulvene (VHF) to dihydroazulene (DHA). In the absence of light, stronger Lewis acids promote the otherwise photoinduced DHA to VHF conversion.......Mild Lewis acids enhance the rate of the thermal conversion of vinylheptafulvene (VHF) to dihydroazulene (DHA). In the absence of light, stronger Lewis acids promote the otherwise photoinduced DHA to VHF conversion....

  17. Degradation of oil products in a soil from a Russian Barents hot-spot during electrodialytic remediation

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Jensen, Pernille Erland;

    2016-01-01

    A highly oil-polluted soil from Krasnoe in North-West Russia was used to investigate the degradation of organic pollutants during electrodialytic remediation. Removal efficiencies were up to 70 % for total hydrocarbons (THC) and up to 65 % for polyaromatic hydrocarbons (PAH). Relatively more...... of the lighter PAH compounds and THC fractions were degraded. A principal component analysis (PCA) revealed a difference in the distribution of PAH compounds after the remediation. The observed clustering of experiments in the PCA scores plot was assessed to be related to the stirring rate. Multivariate analysis...... of the experimental settings and final concentrations in the 12 experiments revealed that the stirring rate of the soil suspension was by far the most important parameter for the remediation for both THC and PAH. Light was the second most important variable for PAH and seems to influence degradation. The experimental...

  18. Fenton-enhanced {gamma}-radiolysis of cyanuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Varghese, Rani [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India); Aravind, Usha K. [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India); Aravindakumar, Charuvila T. [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India)]. E-mail: CT-Aravindakumar@rocketmail.com

    2007-04-02

    Degradation of cyanuric acid (OOOT), a stable end product of oxidative decomposition of atrazine, is investigated in a combined field of gamma radiolysis and fenton reaction. The reaction of hydroxyl radical ({center_dot}OH) at pH 6 was carried out by irradiating N{sub 2}O saturated aqueous solutions containing OOOT (1 x 10{sup -3} mol dm{sup -3}), and this resulted only a marginal degradation (20%). However, when the same reaction was carried out in the presence of varying concentrations of ferrous sulfate ((5-10) x 10{sup -5} mol dm{sup -3}), the decay of OOOT has been enhanced to more than 80%. This decay followed a first order kinetics. Nearly similar effects were observed with another triazine derivative, 2,4-dioxohexahydro-1,3,5-triazine (DHT). Two major reaction mechanisms are proposed for the enhanced decay of OOOT. The formation of unstable hydroxyl radical adducts from the reaction of {center_dot}OH which is the result of gamma radiolysis and the Fenton reaction (resulting from the reaction of the added Fe(II) and of the H{sub 2}O{sub 2} from the radiolysis of water), is proposed as the first mechanism. The second mechanism, which is likely the major contributor to degradation, is proposed as the reaction of a nucleophilic adduct, Fe(II)OOH, which could directly react with the electron deficient triazine ring. It is highlighted that such degradation reactions must be explored for the complete degradation of the byproducts of the oxidative decomposition of atrazine.

  19. Gibberellic Acid enhancement of DNA turnover in barley aleurone cells.

    Science.gov (United States)

    Taiz, L; Starks, J E

    1977-08-01

    When imbibed, deembryonated halfseeds from barley (Hordeum vulgare L., var. Himalaya) are incubated in buffer, the DNA content of the aleurone layer increases 25 to 40% over a 24-hour period. In contrast, the DNA of isolated aleurone layers declines by 20% over the same time period. Gibberellic acid (GA) causes a reduction in DNA levels in both halfseed aleurone layers and isolated aleurone layers. GA also increases the specific radioactivity of [(3)H]thymidine-labeled halfseed aleurone layer DNA during the first 12 hours of treatment. Pulse-chase studies demonstrated that the newly synthesized DNA is metabolically labile.The buoyant density on CsCl density gradients of hormone-treated aleurone DNA is identical with that of DNA extracted from whole seedlings. After density-labeling halfseed DNA with 5-bromodeoxyuridine, a bimodal absorption profile is obtained in neutral CsCl. The light band (1.70 g/ml) corresponds to unsubstituted DNA, while the heavy band (1.725-1.74 g/ml) corresponds to a hybrid density-labeled species. GA increases the relative amount of the heavy (hybrid) peak in halfseed aleurone layer DNA, further suggesting that the hormone enhances semiconservative replication in halfseeds.DNA methylation was also demonstrated. Over 60% of the radioactivity from [(3)H-Me]methionine is incorporated into 5-methylcytosine. GA has no effect on the percentage distribution of label among the bases.It was concluded that GA enhances the rate of DNA degradation and DNA synthesis (turnover) in halfseeds, but primarily DNA degradation in isolated aleurone layers. Incorporation by isolated aleurone layers is due to DNA repair. Semiconservative replication apparently plays no physiological role in the hormone response, since both isolated aleurone layers and gamma-irradiated halfseeds respond normally. The hypothesis was advanced that endoreduplication and DNA degradation are means by which the seed stores and mobilizes deoxyribonucleotides for the embryo during

  20. Mechanism involved in enhancement of osteoblast differentiation by hyaluronic acid

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Michinao [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Ariyoshi, Wataru [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Iwanaga, Kenjiro [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Okinaga, Toshinori [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Habu, Manabu [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Yoshioka, Izumi [Division of Oral and Maxillofacial Surgery, Department of Medicine of Sensory and Motor Organs, University of Miyazaki, Kiyotake, Miyazaki 889-1692 (Japan); Tominaga, Kazuhiro [Division of Maxillofacial Diagnostic and Surgical Science, Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Oral Bioresearch Center, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Nishihara, Tatsuji, E-mail: tatsujin@kyu-dent.ac.jp [Division of Infections and Molecular Biology, Department of Health Promotion, Kyushu Dental College, Kitakyushu 803-8580 (Japan); Oral Bioresearch Center, Kyushu Dental College, Kitakyushu 803-8580 (Japan)

    2011-02-25

    Research highlights: {yields} In this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. {yields} MG63 cells were incubated with BMP-2 and HA for various time periods. {yields} Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. {yields} HA enhanced BMP-2 induces osteoblastic differentiation in MG63 cells via down-regulation of BMP-2 antagonists and ERK phosphorylation. -- Abstract: Objectives: Bone morphogenetic protein-2 (BMP-2) is expected to be utilized to fill bone defects and promote healing of fractures. However, it is unable to generate an adequate clinical response for use in bone regeneration. Recently, it was reported that glycosaminoglycans, including heparin, heparan sulfate, keratan sulfate, dermatan sulfate, chondroitin-4-sulfate, chondroitin-6-sulfate, and hyaluronic acid (HA), regulate BMP-2 activity, though the mechanism by which HA regulates osteogenic activities has not been fully elucidated. The aim of this study was to investigate the effects of HA on osteoblast differentiation induced by BMP-2. Materials and methods: Monolayer cultures of osteoblastic lineage MG63 cells were incubated with BMP-2 and HA for various time periods. To determine osteoblastic differentiation, alkaline phosphatase (ALP) activity in the cell lysates was quantified. Phosphorylation of Smad 1/5/8, p38, and ERK proteins was determined by Western blot analysis. To elucidate the nuclear translocation of phosphorylated Smad 1/5/8, stimulated cells were subjected to immunofluorescence microscopy. To further elucidate the role of HA in enhancement of BMP-2-induced Smad signaling, mRNA expressions of the BMP-2 receptor antagonists noggin and follistatin were detected using real-time RT-PCR. Results: BMP-2-induced ALP activation, Smad 1/5/8 phosphorylation, and

  1. Enantioseparation of Amino Acids by Micelle-Enhanced Ultrafiltration : Experimental and Theoretical Studies of Copper(II) Amino Acid Interactions

    NARCIS (Netherlands)

    Bruin, de T.J.M.

    2000-01-01

    A micelle-enhanced ultrafiltration system, which can potentially be used for large scale separations, has been used to investigate the resolution of amino acid enantiomers. For this purpose amino acid derivatives were synthesized, which in combination with copper(II) ions were used as chiral selecto

  2. Accumulation of eicosapolyenoic acids enhances sensitivity to abscisic acid and mitigates the effects of drought in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Yuan, Xiaowei; Li, Yaxiao; Liu, Shiyang; Xia, Fei; Li, Xinzheng; Qi, Baoxiu

    2014-04-01

    IgASE1, a C₁₈ Δ(9)-specific polyunsaturated fatty acid elongase from the marine microalga Isochrysis galbana, is able to convert linoleic acid and α-linolenic acid to eicosadienoic acid and eicosatrienoic acid in Arabidopsis. Eicosadienoic acid and eicosatrienoic acid are precursors of arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid, which are synthesized via the Δ(8) desaturation biosynthetic pathways. This study shows that the IgASE1-expressing transgenic Arabidopsis exhibited altered morphology (decreased leaf area and biomass) and enhanced drought resistance compared to wild-type plants. The transgenic Arabidopsis were hypersensitive to abscisic acid (ABA) during seed germination, post-germination growth, and seedling development. They had elevated leaf ABA levels under well-watered and dehydrated conditions and their stomata were more sensitive to ABA. Exogenous application of eicosadienoic acid and eicosatrienoic acid can mimic ABA and drought responses in the wild type plants, similar to that found in the transgenic ones. The transcript levels of genes involved in the biosynthesis of ABA (NCED3, ABA1, AAO3) as well as other stress-related genes were upregulated in this transgenic line upon osmotic stress (300 mM mannitol). Taken together, these results indicate that these two eicosapolyenoic acids or their derived metabolites can mitigate the effects of drought in transgenic Arabidopsis, at least in part, through the action of ABA.

  3. Electroremediation of straw and co-combustion ash under acidic conditions

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2009-01-01

    Biomass, such as wood and straw, is currently used in EU as a renewable energy source for energy production and this application is expected to rise in coming years. Combined heat and power installations produce fly ash, which is considered hazardous waste. The fly ash management issue should...... be addressed before biomass combustion is considered a truly sustainable technology. The electrodialytic process is a remediation technique able to assist the management of fly ash. For this work, straw and co-combustion of wood ash are briefly characterized and their electrodialytic treatment is carried out...... under acidic conditions.Straw ashes presented high removal rates for Ca, Cu, Cr and particularly for Cd, which has been reduced to a level bellow the established by Danish regulations. Acidification also induced a high dissolution and a lower pH of the ash. Fly ash from co-combustion of wood presents...

  4. Enhancing tolerance of rice (Oryza sativa) to simulated acid rain by exogenous abscisic acid.

    Science.gov (United States)

    Wu, Xi; Liang, Chanjuan

    2016-12-16

    Abscisic acid (ABA) regulates much important plant physiological and biochemical processes and induces tolerance to different stresses. Here, we studied the regulation of exogenous ABA on adaptation of rice seedlings to simulated acid rain (SAR) stress by measuring biomass dry weight, stomatal conductance, net photosynthesis rate, nutrient elements, and endogenous hormones. The application of 10 μM ABA alleviated the SAR-induced inhibition on growth, stomatal conductance, net photosynthesis rate, and decreases in contents of nutrient (K, Mg, N, and P) and hormone (auxin, gibberellins, and zeatin). Moreover, 10 μM ABA could stimulate the Ca content as signaling molecules under SAR stress. Contrarily, the application of 100 μM ABA aggravated the SAR-induced inhibition on growth, stomatal conductance, net photosynthesis rate, and contents of nutrient and hormone. The results got after a 5-day recovery (without SAR) show that exogenous 10 μM ABA can promote self-restoration process in rice whereas 100 μM ABA hindered the restoration by increasing deficiency of nutrients and disturbing the balance of hormones. These results confirmed that exogenous ABA at proper concentration could enhance the tolerance of rice to SAR stress.

  5. Lowering of phytic acid content by enhancement of phytase and acid phosphatase activities during sunflower germination

    Directory of Open Access Journals (Sweden)

    Juliana da Silva Agostini

    2010-08-01

    Full Text Available The objective of this work was to investigate the germination of hybrid sunflowers BRS191 and C11 as a means of lowering phytic acid (PA content by enhancing the activity of endogenous phytase and acid phosphatase. The concentration of PA in hybrid sunflower achenes varied from 2.16 to 2.83g/100g of sample (p O objetivo deste trabalho foi investigar a germinação de girassóis híbridos BRS 191 e C11 com finalidade de reduzir o teor de AF e aumentar as atividades de phytases e fosfatases endógenas. A concentração do AF nos aquênios de girassóis híbridos variou de 2,16 a 2,83 g /100g de amostra (p< 0,005. As atividades de fitases e fosfatases de girassóis BRS191 e C11 foram elevadas no 4º e 5º dia de germinação, respectivamente, com liberação do fósforo necessário para o desenvolvimento da semente. Estes resultados indicam que o AF do girassol hibrido reduz e a atividade de phytase aumenta em períodos distintos da germinação, possibilitando assim a aplicação desta enzima no controle do teor de AF em cereais, melhorando o seu valor nutricional.

  6. An optimized probucol microencapsulated formulation integrating a secondary bile acid (deoxycholic acid as a permeation enhancer

    Directory of Open Access Journals (Sweden)

    Mooranian A

    2014-09-01

    Full Text Available Armin Mooranian,1 Rebecca Negrulj,1 Nigel Chen-Tan,2 Gerald F Watts,3 Frank Arfuso,4 Hani Al-Salami11Biotechnology and Drug Development Research Laboratory, School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, 2Faculty of Science and Engineering, Curtin University, 3School of Medicine and Pharmacology, Royal Perth Hospital, University of Western Australia, 4School of Biomedical Science, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, AustraliaAbstract: The authors have previously designed, developed, and characterized a novel microencapsulated formulation as a platform for the targeted delivery of therapeutics in an animal model of type 2 diabetes, using the drug probucol (PB. The aim of this study was to optimize PB microcapsules by incorporating the bile acid deoxycholic acid (DCA, which has good permeation-enhancing properties, and to examine its effect on microcapsules’ morphology, rheology, structural and surface characteristics, and excipients’ chemical and thermal compatibilities. Microencapsulation was carried out using a BÜCHI-based microencapsulating system established in the authors’ laboratory. Using the polymer sodium alginate (SA, two microencapsulated formulations were prepared: PB-SA (control and PB-DCA-SA (test at a constant ratio (1:30 and 1:3:30, respectively. Complete characterization of the microcapsules was carried out. The incorporation of DCA resulted in better structural and surface characteristics, uniform morphology, and stable chemical and thermal profiles, while size and rheological parameters remained similar to control. In addition, PB-DCA-SA microcapsules showed good excipients’ compatibilities, which were supported by data from differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray studies, suggesting

  7. Enhanced functional properties of tannic acid after thermal hydrolysis

    Science.gov (United States)

    Thermal hydrolysis processing of fresh tannic acid was carried out in a closed reactor at four different temperatures (65, 100, 150 and 200°C). Pressures reached in the system were 1.3 and 4.8 MPa at 150 and 200°C, respectively. Hydrolysis products (gallic acid and pyrogallol) were separated and qua...

  8. Genetic Engineering of Rhizopus for Enhancing Lactic Acid Production

    Science.gov (United States)

    The fungus Rhizopus is frequently used to convert, or ferment sugars obtained from agricultural crops to lactic acid. This natural product has long been utilized by the food industry as an additive for preservation, flavor, and acidity. Additionally, it is used for the manufacture of environmental...

  9. Enhanced Production of Carboxylic Acids by Engineering of Rhizopus

    Science.gov (United States)

    The fungus Rhizopus is frequently used to convert, or ferment sugars obtained from agricultural crops to lactic acid. This natural product has long been utilized by the food industry as an additive for preservation, flavor, and acidity. Additionally, it is used for the manufacture of environmental...

  10. Increased Production of Fatty Acids and Triglycerides in Aspergillus oryzae by Enhancing Expressions of Fatty Acid Synthesis-Related Genes

    Energy Technology Data Exchange (ETDEWEB)

    Tamano, Koichi; Bruno, Kenneth S.; Karagiosis, Sue A.; Culley, David E.; Deng, Shuang; Collett, James R.; Umemura, Myco; Koike, Hideaki; Baker, Scott E.; Machida, Masa

    2013-01-01

    Microbial production of fats and oils is being developedas a means of converting biomass to biofuels. Here we investigate enhancing expression of enzymes involved in the production of fatty acids and triglycerides as a means to increase production of these compounds in Aspergillusoryzae. Examination of the A.oryzaegenome demonstrates that it contains twofatty acid synthases and several other genes that are predicted to be part of this biosynthetic pathway. We enhancedthe expressionof fatty acid synthesis-related genes by replacing their promoters with thepromoter fromthe constitutively highly expressedgene tef1. We demonstrate that by simply increasing the expression of the fatty acid synthasegenes we successfullyincreasedtheproduction of fatty acids and triglyceridesby more than two fold. Enhancement of expression of the fatty acid pathway genes ATP-citrate lyase and palmitoyl-ACP thioesteraseincreasedproductivity to a lesser extent.Increasing expression ofacetyl-CoA carboxylase caused no detectable change in fatty acid levels. Increases in message level for each gene were monitored usingquantitative real-time RT-PCR. Our data demonstrates that a simple increase in the abundance of fatty acid synthase genes can increase the detectable amount of fatty acids.

  11. Enhancing the crystalline degree of carbon nanotubes by acid treatment, air oxidization and heat treatment

    Institute of Scientific and Technical Information of China (English)

    Chensha Li; Baoyou Zhang; Xingjuan Chen; Xiaoqing Hu; Ji Liang

    2005-01-01

    Three approaches of treating carbon nanotubes (CNTs) including acid treatment, air oxidization and heat treatment at high temperature were studied to enhance the crystalline degree of carbon nanotubes. High temperature heat-treatment elevates the crystalline degree of carbon nanotubes. Acid treatment removes parts of amorphous carbonaceous matter through its oxidization effect.Air oxidization disperses carbon nanotubes and amorphous carbonaceous matter. The treatment of combining acid treatment with heat-treatment further elevates the crystalline degree of carbon nanotubes comparing with acid treatment or heat-treatment. The combination of the three treatments creates the thorough effects of enhancing the crystalline degree of carbon nanotubes.

  12. The memory-enhancing effect of erucic acid on scopolamine-induced cognitive impairment in mice.

    Science.gov (United States)

    Kim, Eunji; Ko, Hae Ju; Jeon, Se Jin; Lee, Sunhee; Lee, Hyung Eun; Kim, Ha Neul; Woo, Eun-Rhan; Ryu, Jong Hoon

    2016-03-01

    Erucic acid is a monounsaturated omega-9 fatty acid isolated from the seed of Raphanus sativus L. that is known to normalize the accumulation of very long chain fatty acids in the brains of patients suffering from X-linked adrenoleukodystrophy. Here, we investigated whether erucic acid enhanced cognitive function or ameliorated scopolamine-induced memory impairment using the passive avoidance, Y-maze and Morris water maze tasks. Erucic acid (3mg/kg, p.o.) enhanced memory performance in normal naïve mice. In addition, erucic acid (3mg/kg, p.o.) ameliorated scopolamine-induced memory impairment, as assessed via the behavioral tasks. We then investigated the underlying mechanism of the memory-enhancing effect of erucic acid. The administration of erucic acid increased the phosphorylation levels of phosphatidylinositide 3-kinase (PI3K), protein kinase C zeta (PKCζ), extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB) and additional protein kinase B (Akt) in the hippocampus. These results suggest that erucic acid has an ameliorative effect in mice with scopolamine-induced memory deficits and that the effect of erucic acid is partially due to the activation of PI3K-PKCζ-ERK-CREB signaling as well as an increase in phosphorylated Akt in the hippocampus. Therefore, erucic acid may be a novel therapeutic agent for diseases associated with cognitive deficits, such as Alzheimer's disease.

  13. Enhanced expression of aconitase raises acetic acid resistance in Acetobacter aceti.

    Science.gov (United States)

    Nakano, Shigeru; Fukaya, Masahiro; Horinouchi, Sueharu

    2004-06-15

    Acetobacter spp. are used for industrial vinegar production because of their high ability to oxidize ethanol to acetic acid and high resistance to acetic acid. Two-dimensional gel electrophoretic analysis of a soluble fraction of Acetobacter aceti revealed the presence of several proteins whose production was enhanced, to various extents, in response to acetic acid in the medium. A protein with an apparent molecular mass of 100 kDa was significantly enhanced in amount by acetic acid and identified to be aconitase by NH2-terminal amino acid sequencing and subsequent gene cloning. Amplification of the aconitase gene by use of a multicopy plasmid in A. aceti enhanced the enzymatic activity and acetic acid resistance. These results showed that aconitase is concerned with acetic acid resistance. Enhancement of the aconitase activity turned out to be practically useful for acetic acid fermentation, because the A. aceti transformant harboring multiple copies of the aconitase gene produced a higher concentration of acetic acid with a reduced growth lag-time.

  14. Systematic Procedure for Integrated Process Operation: Reverse Electro-Enhanced Dialysis (REED) during Lactic Acid Fermentation

    DEFF Research Database (Denmark)

    Prado Rubio, Oscar Andres; Jørgensen, Sten Bay; Jonsson, Gunnar Eigil

    2011-01-01

    The integration of lactic acid fermentation and Reverse Electro-Enhanced Dialysis (REED) is investigated based upon previously developed mathematical models. A goal driven process and operation design procedure is proposed and partially investigated. The conceptual analysis of the processes...

  15. Fe-nitrilotriacetic acid coordination polymer nanowires: an effective sensing platform for fluorescence-enhanced nucleic acid detection

    Science.gov (United States)

    Zhou, Yunchun; Liu, Qian; Sun, Xuping; Kong, Rongmei

    2017-02-01

    The determination of specific nucleic acid sequences is key in identifying disease-causing pathogens and genetic diseases. In this paper we report the utilization of Fe-nitrilotriacetic acid coordination polymer nanowires as an effective nanoquencher for fluorescence-enhanced nucleic acid detection. The detection is fast and the whole process can be completed within 15 min. This nanosensor shows a low detection limit of 0.2 nM with selectivity down to single-base mismatch. This work provides us with an attractive sensing platform for applications.

  16. CO2-enhanced extraction of acetic acid from fermented wastewater

    NARCIS (Netherlands)

    Reyhanitash, E.; Zaalberg, B.; IJmker, H.M.; Kersten, S.R.A.; Schuur, B.

    2015-01-01

    The industrial process of recovering fermentation-based volatile fatty acids (VFAs) utilizes H2SO4 to acidify the fermentation broth containing VFA-salts [e.g. Ca(CH3COO)2] to enable formation of molecular VFAs. Molecular VFAs are then recovered by liquid–liquid extraction. However, acidification wi

  17. Peptide Nucleic Acids Having Enhanced Binding Affinity and Sequence Specificity

    DEFF Research Database (Denmark)

    1998-01-01

    A novel class of compounds, known as peptide nucleic acids, bind complementary DNA and RNA strands more strongly than a corresponding DNA strand, and exhibit increased sequence specificity and binding affinity. Methods of increasing binding affinity and sequence specificity of peptide nucleic aci...

  18. Enhancement of the ferromagnetic order of graphite after sulphuric acid treatment

    OpenAIRE

    Barzola-Quiquia, J.; W. Böhlmann; Esquinazi, P.; Schadewitz, A.; Ballestar, A.; Dusari, S.; Schultze-Nobre, L.; Kersting, B.

    2011-01-01

    We have studied the changes in the ferromagnetic behavior of graphite powder and graphite flakes after treatment with diluted sulphuric acid. We show that this kind of acid treatment enhances substantially the ferromagnetic magnetization of virgin graphite micrometer size powder as well as in graphite flakes. The anisotropic magnetoresistance (AMR) amplitude at 300 K measured in a micrometer size thin graphite flake after acid treatment reaches values comparable to polycrystalline cobalt.

  19. Lactic Acid Recovery in Electro-Enhanced Dialysis: Modelling and Validation

    DEFF Research Database (Denmark)

    Prado Rubio, Oscar Andres; Jørgensen, Sten Bay; Jonsson, Gunnar Eigil

    2009-01-01

    and migration across the boundary layers and membranes. The model is validated for Donnan dialysis recovery of different monoprotic carboxylic acids. Simulations are used to evaluate the potential enhancement of lactate fluxes under current load conditions, referred as Electro-Enhanced Dialysis operation...

  20. Enhanced silicate weathering is not limited by silicic acid saturation

    NARCIS (Netherlands)

    Schuiling, R.D.; Wilson, S.A.; Power, I.M.

    2011-01-01

    Enhanced weathering of olivine as a means of sequestering carbon is investigated by Köhler et al. (1). Specifically, the study discusses the potential distribution of fine olivine powder, obtained from dunite mines, in the humid tropic regions of the Amazon and Congo River catchments. Olivine (forst

  1. Degradation of Fructans and Production of Propionic Acid by Bacteroides thetaiotaomicron are Enhanced by the Shortage of Amino Acids.

    Science.gov (United States)

    Adamberg, Signe; Tomson, Katrin; Vija, Heiki; Puurand, Marju; Kabanova, Natalja; Visnapuu, Triinu; Jõgi, Eerik; Alamäe, Tiina; Adamberg, Kaarel

    2014-01-01

    Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory) and levan (synthesized using levansucrase from Pseudomonas syringae), two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (degree of polymerization > 3). Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h), followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of d-lactate (82 ± 33 mmol/gDW) occurred in parallel with extensive consumption (up to 17 mmol/gDW) of amino acids, especially Ser, Thr, and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will

  2. Degradation of fructans and production of propionic acid by Bacteroides thetaiotaomicron are enhanced by shortage of amino acids

    Directory of Open Access Journals (Sweden)

    Signe eAdamberg

    2014-12-01

    Full Text Available Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by the catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory and levan (synthesized using levansucrase from Pseudomonas syringae, two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (DP > 3. Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h, followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of D-lactate (82 ± 33 mmol/gDW occurred in parallel with extensive consumption (up to 17 mmol/gDW of amino acids, especially Ser, Thr and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will be studied in

  3. Afferent signalling from the acid-challenged rat stomach is inhibited and gastric acid elimination is enhanced by lafutidine

    Directory of Open Access Journals (Sweden)

    Holzer Peter

    2009-06-01

    Full Text Available Abstract Background Lafutidine is a histamine H2 receptor antagonist, the gastroprotective effect of which is related to its antisecretory activity and its ability to activate a sensory neuron-dependent mechanism of defence. The present study investigated whether intragastric administration of lafutidine (10 and 30 mg/kg modifies vagal afferent signalling, mucosal injury, intragastric acidity and gastric emptying after gastric acid challenge. Methods Adult rats were treated with vehicle, lafutidine (10 – 30 mg/kg or cimetidine (10 mg/kg, and 30 min later their stomachs were exposed to exogenous HCl (0.25 M. During the period of 2 h post-HCl, intragastric pH, gastric volume, gastric acidity and extent of macroscopic gastric mucosal injury were determined and the activation of neurons in the brainstem was visualized by c-Fos immunocytochemistry. Results Gastric acid challenge enhanced the expression of c-Fos in the nucleus tractus solitarii but caused only minimal damage to the gastric mucosa. Lafutidine reduced the HCl-evoked expression of c-Fos in the NTS and elevated the intragastric pH following intragastric administration of excess HCl. Further analysis showed that the gastroprotective effect of lafutidine against excess acid was delayed and went in parallel with facilitation of gastric emptying, measured indirectly via gastric volume changes, and a reduction of gastric acidity. The H2 receptor antagonist cimetidine had similar but weaker effects. Conclusion These observations indicate that lafutidine inhibits the vagal afferent signalling of a gastric acid insult, which may reflect an inhibitory action on acid-induced gastric pain. The ability of lafutidine to decrease intragastric acidity following exposure to excess HCl cannot be explained by its antisecretory activity but appears to reflect dilution and/or emptying of the acid load into the duodenum. This profile of actions emphasizes the notion that H2 receptor antagonists can protect

  4. Enhanced fatty acid flux triggered by adiponectin overexpression.

    Science.gov (United States)

    Shetty, Shoba; Ramos-Roman, Maria A; Cho, You-Ree; Brown, Jonathan; Plutzky, Jorge; Muise, Eric S; Horton, Jay D; Scherer, Philipp E; Parks, Elizabeth J

    2012-01-01

    Adiponectin overexpression in mice increases insulin sensitivity independent of adiposity. Here, we combined stable isotope infusion and in vivo measurements of lipid flux with transcriptomic analysis to characterize fatty acid metabolism in transgenic mice that overexpress adiponectin via the aP2-promoter (ADNTg). Compared with controls, fasted ADNTg mice demonstrated a 31% reduction in plasma free fatty acid concentrations (P = 0.008), a doubling of ketones (P = 0.028), and a 68% increase in free fatty acid turnover in plasma (15.1 ± 1.5 vs. 25.3 ± 6.8 mg/kg · min, P = 0.011). ADNTg mice had 2-fold more brown adipose tissue mass, and triglyceride synthesis and turnover were 5-fold greater in this organ (P = 0.046). Epididymal white adipose tissue was slightly reduced, possibly due to the approximately 1.5-fold increase in the expression of genes involved in oxidation (peroxisome proliferator-activated receptor α, peroxisome proliferator-activated receptor-γ coactivator 1α, and uncoupling protein 3). In ADNTg liver, lipogenic gene expression was reduced, but there was an unexpected increase in the expression of retinoid pathway genes (hepatic retinol binding protein 1 and retinoic acid receptor beta and adipose Cyp26A1) and liver retinyl ester content (64% higher, P < 0.02). Combined, these data support a physiological link between adiponectin signaling and increased efficiency of triglyceride synthesis and hydrolysis, a process that can be controlled by retinoids. Interactions between adiponectin and retinoids may underlie adiponectin's effects on intermediary metabolism.

  5. Performance enhancement of phosphoric acid fuel cell using phosphosilicate gel based electrolyte

    Institute of Scientific and Technical Information of China (English)

    Kajari Kargupta; Swati Saha; Dipali Banerjee; Mrinal Seal; Saibal Ganguly

    2012-01-01

    Replacement of phosphoric acid electrolyte by phosphosilicate gel based electrolytes is proposed for performance enhancement of phosphoric acid fuel cell (PAFG).Phosphosilicate gel in paste form and in powder form is synthesized from tetraethoxysilane and orthophosphoric acid using sol-gel method for two different P/Si ratio of 5 and 1.5 respectively.Replacement of phosphoric acid electrolyte by phosphosilicate gel paste enhances the peak power generation of the fuel cell by 133% at 120 ℃ cell temperature; increases the voltage generation in the ohmic regime and extends the maximum possible load current.Polyinyl alcohol (PVA) is used to bind the phosphosilicate gel powder and to form the hybrid crosslinked gel polymer electrolyte membrane.Soaking the membrane with phosphoric acid solution,instead of that with water improves the proton conductivity of the membrane,enhances the voltage and power generation by the fuel cell and extends the maximum possible operating temperature.At lower operating temperature of 70 ℃,peak power produced by phosphosilicate gel polymer electrolyte membrane fuel cell ( PGMFC ) is increased by 40% compared to that generated by phosphoric acid fuel cell ( PAFC ).However,the performance of composite membrane diminishes as the cell temperature increases.Thus phosphosilicate gel in paste form is found to be a good alternative of phosphoric acid electrolyte at medium operating temperature range while phosphosilicate gel-PVA composite offers performance enhancement at low operating temperatures.

  6. Gallic Acid Is an Antagonist of Semen Amyloid Fibrils That Enhance HIV-1 Infection.

    Science.gov (United States)

    LoRicco, Josephine G; Xu, Changmingzi Sherry; Neidleman, Jason; Bergkvist, Magnus; Greene, Warner C; Roan, Nadia R; Makhatadze, George I

    2016-07-01

    Recent in vitro studies have demonstrated that amyloid fibrils found in semen from healthy and HIV-infected men, as well as semen itself, can markedly enhance HIV infection rates. Semen fibrils are made up of multiple naturally occurring peptide fragments derived from semen. The best characterized of these fibrils are SEVI (semen-derived enhancer of viral infection), made up of residues 248-286 of prostatic acidic phosphatase, and the SEM1 fibrils, made up of residues 86-107 of semenogelin 1. A small molecule screen for antagonists of semen fibrils identified four compounds that lowered semen-mediated enhancement of HIV-1 infectivity. One of the four, gallic acid, was previously reported to antagonize other amyloids and to exert anti-inflammatory effects. To better understand the mechanism by which gallic acid modifies the properties of semen amyloids, we performed biophysical measurements (atomic force microscopy, electron microscopy, confocal microscopy, thioflavin T and Congo Red fluorescence assays, zeta potential measurements) and quantitative assays on the effects of gallic acid on semen-mediated enhancement of HIV infection and inflammation. Our results demonstrate that gallic acid binds to both SEVI and SEM1 fibrils and modifies their surface electrostatics to render them less cationic. In addition, gallic acid decreased semen-mediated enhancement of HIV infection but did not decrease the inflammatory response induced by semen. Together, these observations identify gallic acid as a non-polyanionic compound that inhibits semen-mediated enhancement of HIV infection and suggest the potential utility of incorporating gallic acid into a multicomponent microbicide targeting both the HIV virus and host components that promote viral infection.

  7. PPAR{delta} is a fatty acid sensor, which enhances mitochondrial oxidation in insulin

    DEFF Research Database (Denmark)

    Ravnskjaer, Kim; Frigerio, Francesca; Boergesen, Michael;

    2010-01-01

    against adverse effects on GSIS associated with prolonged fatty acid exposure. The presented results indicate that the nuclear receptor PPARdelta is a fatty acid sensor that adapts beta-cell mitochondrial function to long-term changes in unsaturated fatty acid levels. As maintenance of mitochondrial...... is the PPAR subtype expressed at the highest level in insulinoma cells and rat pancreatic islets. Furthermore, PPARdelta displays high transcriptional activity and acts in pronounced synergy with RXR. Interestingly, unsaturated fatty acids mimic the effects of synthetic PPARdelta agonists. Using sh......RNA-mediated knockdown we demonstrate that the ability of unsaturated fatty acids to stimulate fatty acid metabolism is dependent on PPARdelta. Activation of PPARdelta increases the fatty acid oxidation potential in INS-1E beta-cells, enhances glucose-stimulated insulin secretion (GSIS) from islets, and protects GSIS...

  8. Plasmon resonance enhancement of nonlinear properties of amino acids

    Science.gov (United States)

    de Araujo, Renato E.; Rativa, Diego; Gomes, Anderson S. L.

    2007-02-01

    Here we analyze the influence of 9 nm (mean diameter) silver particles on the nonlinear properties of intrinsic cell molecules. A novel high sensitivity thermal managed eclipse Z-scan technique with a femtosecond laser system was used to analyze the nonlinear susceptibility of water solution of fluorescent and non-fluorescent amino acids (Tryptophan, Tyrosine, Phenylalanine, Proline and Histidine) with different concentration of silver nanoparticles. The generalized Maxwell Garnett model is used to explain the behavior of the measured nonlinear refractive index with the change of the nanoparticles concentration in the sample.

  9. Clavulanic acid increases dopamine release in neuronal cells through a mechanism involving enhanced vesicle trafficking

    Science.gov (United States)

    Kost, Gina Chun; Selvaraj, Senthil; Lee, Young Bok; Kim, Deog Joong; Ahn, Chang-Ho; Singh, Brij B

    2011-01-01

    Clavulanic acid is a CNS-modulating compound with exceptional blood-brain barrier permeability and safety profile. Clavulanic acid has been proposed to have anti-depressant activity and is currently entering Phase IIb clinical trials for the treatment of Major Depressive Disorder (MDD). Studies have also shown that clavulanic acid suppresses anxiety and enhances sexual functions in rodent and primate models by a mechanism involving central nervous system (CNS) modulation, although its detailed mechanism of action has yet to be elucidated. To further examine its potential as a CNS modulating agent as well as its mechanism of action, we investigated the effects of clavulanic acid in neuronal cells. Our results indicate that clavulanic acid enhances dopamine release in PC12 and SH-SY5Y cells without affecting dopamine synthesis. Furthermore, using affinity chromatography we were able to identify two proteins, Munc18-1 and Rab4 that potentially bind to clavulanic acid and play a critical role in neurosecretion and the vesicle trafficking process. Consistent with this result, an increase in the translocation of Munc18-1 and Rab4 from the cytoplasm to the plasma membrane was observed in clavulanic acid treated cells. Overall, these data suggest that clavulanic acid enhances dopamine release in a mechanism involving Munc18-1 and Rab4 modulation and warrants further investigation of its therapeutic use in CNS disorders, such as depression. PMID:21964384

  10. Clavulanic acid increases dopamine release in neuronal cells through a mechanism involving enhanced vesicle trafficking.

    Science.gov (United States)

    Kost, Gina Chun; Selvaraj, Senthil; Lee, Young Bok; Kim, Deog Joong; Ahn, Chang-Ho; Singh, Brij B

    2011-10-24

    Clavulanic acid is a CNS-modulating compound with exceptional blood-brain barrier permeability and safety profile. Clavulanic acid has been proposed to have anti-depressant activity and is currently entering Phase IIb clinical trials for the treatment of Major Depressive Disorder (MDD). Studies have also shown that clavulanic acid suppresses anxiety and enhances sexual functions in rodent and primate models by a mechanism involving central nervous system (CNS) modulation, although its detailed mechanism of action has yet to be elucidated. To further examine its potential as a CNS modulating agent as well as its mechanism of action, we investigated the effects of clavulanic acid in neuronal cells. Our results indicate that clavulanic acid enhances dopamine release in PC12 and SH-SY5Y cells without affecting dopamine synthesis. Furthermore, using affinity chromatography we were able to identify two proteins, Munc18-1 and Rab4 that potentially bind to clavulanic acid and play a critical role in neurosecretion and the vesicle trafficking process. Consistent with this result, an increase in the translocation of Munc18-1 and Rab4 from the cytoplasm to the plasma membrane was observed in clavulanic acid treated cells. Overall, these data suggest that clavulanic acid enhances dopamine release in a mechanism involving Munc18-1 and Rab4 modulation and warrants further investigation of its therapeutic use in CNS disorders, such as depression.

  11. Combined gadoxetic acid and gadofosveset enhanced liver MRI for detection and characterization of liver metastases

    Energy Technology Data Exchange (ETDEWEB)

    Bannas, Peter [University of Wisconsin-Madison, Department of Radiology, Madison, WI (United States); University Medical Center Hamburg-Eppendorf, Department of Radiology, University Hospital, Hamburg (Germany); Bookwalter, Candice A.; Ziemlewicz, Tim; Munoz del Rio, Alejandro; Potretzke, Theodora A. [University of Wisconsin-Madison, Department of Radiology, Madison, WI (United States); Motosugi, Utaroh [University of Wisconsin-Madison, Department of Radiology, Madison, WI (United States); University of Yamanashi, Department of Radiology, Yamanashi (Japan); Nagle, Scott K. [University of Wisconsin-Madison, Department of Radiology, Madison, WI (United States); University of Wisconsin-Madison, Department of Medical Physics, Madison, WI (United States); University of Wisconsin-Madison, Department of Pediatrics, Madison, WI (United States); Reeder, Scott B. [University of Wisconsin-Madison, Department of Radiology, Madison, WI (United States); University of Wisconsin-Madison, Department of Medical Physics, Madison, WI (United States); University of Wisconsin-Madison, Department of Biomedical Engineering, Madison, WI (United States); University of Wisconsin-Madison, Department of Medicine, Madison, WI (United States); University of Wisconsin-Madison, Department of Emergency Medicine, Madison, WI (United States)

    2017-01-15

    To compare gadoxetic acid alone and combined gadoxetic acid/gadofosveset trisodium-enhanced liver MRI for detection of metastases and differentiation of metastases from haemangiomas. Ninety-one patients underwent gadoxetic acid-enhanced liver MRI before and after additional injection of gadofosveset. First, two readers retrospectively identified metastases on gadoxetic acid alone enhanced delayed hepatobiliary phase T1-weighted images together with all other MR images (dynamic images, T2-weighted images, diffusion-weighted images). Second, readers assessed additional T1-weighted images obtained after administration of gadofosveset trisodium. For both interpretations, readers rated lesion conspicuity and confidence in differentiating metastases from haemangiomas. Results were compared using alternative free-response receiver-operating characteristic (AFROC) and conventional ROC methods. Histology and follow-up served as reference standard. There were 145 metastases and 16 haemangiomas. Both readers detected more metastases using combined gadoxetic acid/gadofosveset (reader 1 = 130; reader 2 = 124) compared to gadoxetic acid alone (reader 1 = 104; reader 2 = 103). Sensitivity of combined gadoxetic acid/gadofosveset (reader 1 = 90 %; reader 2 = 86 %) was higher than that of gadoxetic acid alone (reader 1 = 72 %; reader 2 = 71 %, both P < 0.01). AFROC-AUC was higher for the combined technique (0.92 vs. 0.86, P < 0.001). Sensitivity for correct differentiation of metastases from haemangiomas was higher for the combined technique (reader 1 = 98 %; reader 2 = 99 % vs. reader 1 = 86 %; reader 2 = 91 %, both P < 0.01). ROC-AUC was significantly higher for the combined technique (reader 1 = 1.00; reader 2 = 1.00 vs. reader 1 = 0.87; reader 2 = 0.92, both P < 0.01). Combined gadoxetic acid/gadofosveset-enhanced MRI improves detection and characterization of liver metastases compared to gadoxetic acid alone. (orig.)

  12. Water-dispersible ascorbic-acid-coated magnetite nanoparticles for contrast enhancement in MRI

    Science.gov (United States)

    Sreeja, V.; Jayaprabha, K. N.; Joy, P. A.

    2015-04-01

    Superparamagnetic iron oxide nanoparticles of size ~5 nm surface functionalized with ascorbic acid (vitamin C) form a stable dispersion in water with a hydrodynamic size of ~30 nm. The anti-oxidant property of ascorbic acid is retained after capping, as evidenced from the capability of converting methylene blue to its reduced leuco form. NMR relaxivity studies show that the ascorbic-acid-coated superparamagnetic iron oxide aqueous nanofluid is suitable as a contrast enhancement agent for MRI applications, coupled with the excellent biocompatibility and medicinal values of ascorbic acid.

  13. Hydroxycinnamic acid derivatives in an aquatic liverwort as possible bioindicators of enhanced UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Arroniz-Crespo, M.; Nunez-Olivera, E. [Universidad de La Rioja, Complejo Cientifico-Tecnologico, Avda. Madre de Dios 51, 26006 Logrono (La Rioja) (Spain); Martinez-Abaigar, J. [Universidad de La Rioja, Complejo Cientifico-Tecnologico, Avda. Madre de Dios 51, 26006 Logrono (La Rioja) (Spain)], E-mail: javier.martinez@unirioja.es

    2008-01-15

    We examined, under laboratory conditions, the physiological responses of the aquatic liverwort Jungermannia exsertifolia subsp. cordifolia to artificially enhanced ultraviolet (UV) radiation for 82 days, especially considering the responses of five hydroxycinnamic acid derivatives. This species lives in mountain streams, where it is exposed to low temperatures and high UV levels, and this combination is believed to increase the adverse effects of UV. Enhanced UV radiation hardly caused any change in several physiological variables indicative of vitality, such as F{sub v}/F{sub m} and chlorophylls/phaeopigments ratio (OD430/OD410). Thus, this liverwort seemed to be tolerant to UV radiation, probably due to the accumulation of three UV-absorbing hydroxycinnamic acid derivatives: p-coumaroylmalic acid, 5''-(7'',8''-dihydroxycoumaroyl)-2-caffeoylmalic acid, and 5''-(7'',8''-dihydroxy-7-O-{beta}-glucosyl-coumaroyl)-2-caffeoylmalic acid. These compounds might serve as bioindicators of enhanced UV radiation. - Several hydroxycinnamic acid derivatives of an aquatic liverwort are induced by enhanced UV radiation and might serve as bioindicators of changes in UV levels.

  14. Reduced Burst Release and Enhanced Oral Bioavailability in Shikimic Acid-Loaded Polylactic Acid Submicron Particles by Coaxial Electrospray.

    Science.gov (United States)

    Wang, Miaomiao; Wang, Yuanwen; Omari-Siaw, Emmanuel; Wang, Shengli; Zhu, Yuan; Xu, Ximing

    2016-08-01

    In this study, using the coaxial electrospray method, we prepared submicron particles of the water-soluble drug shikimic acid (SA) with polylactic acid (PLA) as a polymer, to reduce the burst release and enhance the oral bioavailability. In vitro release study performed in HCl solution (pH 1.2) showed that the coaxial electrospray submicron particles could reduce burst release effect and presented a sustained release profile, compared with free SA and the particles prepared by electrospray method. The absorption of SA in the intestinal tract, studied using an in situ perfusion method in rats, also revealed jejunum as the main absorptive segment followed by duodenum and ileum. Moreover, the SA-loaded particles greatly enhanced the absorption of SA in the tested intestinal segments. The intestinal absorption rate was not enhanced with increasing drug concentration (5-15 μg/mL) which suggested that active transport or facilitated diffusion could play vital role in SA absorption. In addition, the SA-loaded PLA coaxial electrospray particle exhibited a prolonged plasma circulation with enhanced bioavailability after oral administration. In all, the coaxial electrospray technique could provide notable advantages for the oral delivery of SA, thereby enhancing its clinical application.

  15. Fish oil prevents essential fatty acid deficiency and enhances growth: clinical and biochemical implications.

    Science.gov (United States)

    Strijbosch, Robert A M; Lee, Sang; Arsenault, Danielle A; Andersson, Charlotte; Gura, Kathleen M; Bistrian, Bruce R; Puder, Mark

    2008-05-01

    Fish oil, a rich source of omega-3 fatty acids, has never been used as the sole source of lipid in clinical practice for fear of development of essential fatty acid deficiency, as it lacks the believed requisite levels of linoleic acid, an omega-6 fatty acid. The objectives of this study were to establish biochemical standards for fish oil as the sole fat and to test the hypothesis that fish oil contains adequate amounts of omega-6 fatty acids to prevent essential fatty acid deficiency. Forty mice were divided into 2 groups that were either pair fed or allowed to eat ad libitum. In each group, 4 subgroups of 5 mice were fed 1%, 5%, and 10% fish oil diets by weight or a control soybean diet for 9 weeks. Blood was collected at 4 time points, and fatty acid analysis was performed. Food intake and weight status were monitored. All groups but the pair-fed 1% fish oil group gained weight, and the 5% fish oil group showed the highest caloric efficiency in both pair-fed and ad libitum groups. Fatty acid profiles for the 1% fish oil group displayed clear essential fatty acid deficiency, 5% fish oil appeared marginal, and 10% and soybean oil diets were found to prevent essential fatty acid deficiency. Fish oil enhances growth through higher caloric efficiency. We established a total omega-6 fatty acid requirement of between 0.30% and 0.56% of dietary energy, approximately half of the conventionally believed 1% as linoleic acid. This can presumably be attributed to the fact that fish oil contains not only a small amount of linoleic acid, but also arachidonic acid, which has greater efficiency to meet omega-6 fatty acid requirements.

  16. Enhanced uptake of water by oxidatively processed oleic acid

    Directory of Open Access Journals (Sweden)

    A. Asad

    2004-07-01

    Full Text Available A quartz crystal microbalance apparatus has been used to measure the room temperature uptake of water vapour by thin films of oleic acid as a function of relative humidity, both before and following exposure of the films to various partial pressures of gas phase ozone. A rapid increase in the water-sorbing ability of the film is observed as its exposure to ozone is increased, followed by a plateau region in which no additional water is taken up. In this fully-processed region the mass of water taken up by the film is about 4 times that of the unprocessed film. Infrared spectra of the films, measured after variable exposures to ozone, show dramatic increases in both the "free" and hydrogen-bonded O-H stretching regions, and a decrease in the intensity of olefinic features. These results are consistent with the formation of an oxygenated polymeric product or products, as well as the gas phase products previously identified.

  17. Enhanced crystallization of poly (lactic acid) through reactive aliphatic bisamide

    Science.gov (United States)

    Nanthananon, P.; Seadan, M.; Pivsa-Art, S.; Suttiruengwong, S.

    2015-07-01

    The poor crystallization rate of poly (lactic acid) (PLA) is a major drawback in terms of controlling the properties of final products. To overcome this, a nucleating agent is normally applied. In this work, the aliphatic bisamide, N, N'-(1,3-propylene) bis(10-undecenamide) (PBU), having reactive functional groups is used as a crystallization promoter for PLA by adding PBU in various concentration (0.1-0.7 wt%) into PLA together with peroxide via reactive melt blending. The conventional ethylene bis-stearamide(EBS) is used for a comparison. The extruded samples are characterized for gel content and FT-IR spectroscopy. The crystallization behaviour and rate, and spherulites morphology are investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM), respectively. It is found that the addition of PBU into PLA results in the dramatic increase in crystallinity and crystallization rate of PLA compared with neat PLA and PLA added EBS. The crystallinity increases to 24.9-28.3% higher than neat PLA under even cooling rate of 7°C/min. The addition of 0.7 wt% PBU shows the fastest crystallization rate with t1/2 value isothermally crystallized at 130°C of only 6 min. POM images indicate the increase in the nucleation density and very fine spherulitesof PLA added PBU, promoting the fast crystallization.

  18. Enhanced uptake of water by oxidatively processed oleic acid

    Directory of Open Access Journals (Sweden)

    A. Asad

    2004-01-01

    Full Text Available A quartz crystal microbalance apparatus has been used to measure the room temperature uptake of water vapour by thin films of oleic acid as a function of relative humidity, both before and following exposure of the films to various partial pressures of gas phase ozone. A rapid increase in the water-sorbing ability of the film is observed as its exposure to ozone is increased, followed by a plateau region in which additional water is taken up more gradually. In this fully-processed region the mass of water taken up by the film is about 4 times that of the unprocessed film. Infrared spectra of the films, measured after variable exposures to ozone, show dramatic increases in both the 'free' and hydrogen-bonded O-H stretching regions, and a decrease in the intensity of olefinic features. These results are consistent with the formation of an oxygenated polymeric product or products, as well as the gas phase products previously identified.

  19. Ferulic Acid Enhances Peripheral Nerve Regeneration across Long Gaps

    Directory of Open Access Journals (Sweden)

    Sheng-Chi Lee

    2013-01-01

    Full Text Available This study investigated the effect of ferulic acid (FA on peripheral nerve injury. In the in vitro test, the effect of FA on viability of Schwann cells was studied. In the in vivo test, right sciatic nerves of the rats were transected, and a 15 mm nerve defect was created. A nerve conduit made of silicone rubber tube filled with FA (5 and 25 μg/mL, or saline (control, was implanted into the nerve defect. Results show that the number of proliferating Schwann cells increased significantly in the FA-treated group at 25 μg/mL compared to that in the control group. After 8 weeks, the FA-treated group at 25 μg/mL had a higher rate of successful regeneration across the wide gap, a significantly calcitonin gene-related peptide (CGRP staining of the lamina I-II regions in the dorsal horn ipsilateral to the injury, a significantly diminished number of macrophages recruited, and a significantly shortening of the latency and an acceleration of the nerve conductive velocity (NCV of the evoked muscle action potentials (MAPs compared with the controls. In summary, the FA may be useful in the development of future strategies for the treatment of peripheral nerve injury.

  20. Capacity of lactic acid bacteria in immunity enhancement and cancer prevention.

    Science.gov (United States)

    Riaz Rajoka, Muhammad Shahid; Shi, Junling; Zhu, Jing; Shao, Dongyan; Huang, Qingsheng; Yang, Hui; Jin, Mingliang

    2017-01-01

    Lactic acid bacteria are associated with the human gastrointestinal tract. They are important for maintaining the balance of microflora in the human gut. An increasing number of published research reports in recent years have denoted the importance of producing interferon-gamma and IgA for treatment of disease. These agents can enhance the specific and nonspecific immune systems that are dependent on specific bacterial strains. The mechanisms of these effects were revealed in this investigation, where the cell walls of these bacteria were modulated by the cytokine pathways, while the whole bacterial cell mediated the host cell immune system and regulated the production of tumor necrosis factors and interleukins. A supplement of highly active lactic acid bacteria strains provided significant potential to enhance host's immunity, offering prevention from many diseases including some cancers. This review summarizes the current understanding of the function of lactic acid bacteria immunity enhancement and cancer prevention.

  1. Enhanced high temperature thermoelectric response of sulphuric acid treated conducting polymer thin films

    KAUST Repository

    Sarath Kumar, S. R.

    2015-11-24

    We report the high temperature thermoelectric properties of solution processed pristine and sulphuric acid treated poly(3, 4-ethylenedioxythiophene):poly(4-styrenesulfonate) (or PEDOT:PSS) films. The acid treatment is shown to simultaneously enhance the electrical conductivity and Seebeck coefficient of the metal-like films, resulting in a five-fold increase in thermoelectric power factor (0.052 W/m. K ) at 460 K, compared to the pristine film. By using atomic force micrographs, Raman and impedance spectra and using a series heterogeneous model for electrical conductivity, we demonstrate that acid treatment results in the removal of PSS from the films, leading to the quenching of accumulated charge-induced energy barriers that prevent hopping conduction. The continuous removal of PSS with duration of acid treatment also alters the local band structure of PEDOT:PSS, resulting in simultaneous enhancement in Seebeck coefficient.

  2. Lauric acid dependent enhancement in hepatic SCPx protein requires an insulin deficient environment.

    Science.gov (United States)

    Lopez, Dayami; Niesen, Melissa; Bedi, Mohini; McLean, Mark P

    2008-02-01

    Sterol carrier protein X (SCPx) is a peroxisomal protein with both lipid transfer and thiolase activity. Treating with the fatty acid, lauric acid, induced SCPx mRNA levels in rat liver and in rat hepatoma H4IIE cells but enhanced protein levels of SCPx and the thiolase produced as a post-translational modification of SCPx were only seen in H4IIE cells. Further investigation revealed that the presence of insulin can mask lauric acid effects on the SCPx gene especially at the protein level. These data are in agreement with the findings that diabetes, a medical condition characterized by high levels of fatty acids in an insulin deficient environment, enhances the hepatic expression of SCPx.

  3. Elucidating the role of ferrous ion cocatalyst in enhancing dilute acid pretreatment of lignocellulosic biomass

    Directory of Open Access Journals (Sweden)

    Wei Hui

    2011-11-01

    Full Text Available Abstract Background Recently developed iron cocatalyst enhancement of dilute acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. In the current study, our aim was to identify several essential factors that contribute to ferrous ion-enhanced efficiency during dilute acid pretreatment of biomass and to initiate the investigation of the mechanisms that result in this enhancement. Results During dilute acid and ferrous ion cocatalyst pretreatments, we observed concomitant increases in solubilized sugars in the hydrolysate and reducing sugars in the (insoluble biomass residues. We also observed enhancements in sugar release during subsequent enzymatic saccharification of iron cocatalyst-pretreated biomass. Fourier transform Raman spectroscopy showed that major peaks representing the C-O-C and C-H bonds in cellulose are significantly attenuated by iron cocatalyst pretreatment. Imaging using Prussian blue staining indicated that Fe2+ ions associate with both cellulose/xylan and lignin in untreated as well as dilute acid/Fe2+ ion-pretreated corn stover samples. Analyses by scanning electron microscopy and transmission electron microscopy revealed structural details of biomass after dilute acid/Fe2+ ion pretreatment, in which delamination and fibrillation of the cell wall were observed. Conclusions By using this multimodal approach, we have revealed that (1 acid-ferrous ion-assisted pretreatment increases solubilization and enzymatic digestion of both cellulose and xylan to monomers and (2 this pretreatment likely targets multiple chemistries in plant cell wall polymer networks, including those represented by the C-O-C and C-H bonds in cellulose.

  4. Peptide Nucleic Acids Having Enhanced Binding Affinity, Sequence Specificity and Solubility

    DEFF Research Database (Denmark)

    1998-01-01

    A novel class of compounds, known as peptide nucleic acids, bind complementary DNA and RNA strands more strongly than a corresponding DNA strand, and exhibit increased sequence specificity and solubility. The peptide nucleic acids comprise ligands selected from a group consisting of naturally......-occurring nucleobases and non-naturally-occurring nucleobases attached to a polyamide backbone, and contain C1-C8 alkylamine side chains. Methods of enhancing the solubility, binding affinity and sequence specificity of PNAs are provided....

  5. Unsaturated fatty acids lactose esters: cytotoxicity, permeability enhancement and antimicrobial activity.

    Science.gov (United States)

    Lucarini, Simone; Fagioli, Laura; Campana, Raffaella; Cole, Hannah; Duranti, Andrea; Baffone, Wally; Vllasaliu, Driton; Casettari, Luca

    2016-10-01

    Sugar based surfactants conjugated with fatty acid chains are an emerging broad group of highly biocompatible and biodegradable compounds with established and potential future applications in the pharmaceutical, cosmetic and food industries. In this work, we investigated absorption enhancing and antimicrobial properties of disaccharide lactose, monoesterified with unsaturated fatty acids through an enzymatic synthetic approach. After chemical and cytotoxicity characterizations, their permeability enhancing activity was demonstrated using intestinal Caco-2 monolayers through transepithelial electrical resistance (TEER) and permeability studies. The synthesized compounds, namely lactose palmitoleate (URB1076) and lactose nervonate (URB1077), were shown to exhibit antimicrobial activity versus eight pathogenic species belonging to Gram-positive, Gram-negative microorganisms and fungi.

  6. Gadoxetic acid enhanced MRI for differentiation of FNH and HCA: a single centre experience

    Energy Technology Data Exchange (ETDEWEB)

    Grieser, Christian; Steffen, Ingo G.; Perez Fernandez, Carmen Maria; Hamm, Bernd; Denecke, Timm [Klinik fuer Radiologie, Campus Virchow-Klinikum, Charite - Universitaetsmedizin Berlin, Berlin (Germany); Kramme, Incken-Birthe; Blaeker, Hendrik; Kilic, Ergin [Institut fuer Pathologie, Campus Virchow-Klinikum, Charite - Universitaetsmedizin Berlin, Berlin (Germany); Seehofer, Daniel [Klinik fuer Allgemein, Viszeral- und Transplantationschirurgie, Campus Virchow-Klinikum, Charite - Universitaetsmedizin Berlin, Berlin (Germany); Schott, Eckart [Medizinische Klinik m.S. Hepatologie und Gastroenterologie, Campus Virchow-Klinikum, Charite - Universitaetsmedizin Berlin, Berlin (Germany)

    2014-06-15

    Evaluation of enhancement characteristics of histopathologically confirmed focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HCAs) with gadoxetic acid-enhanced MRI. Sixty-eight patients with 115 histopathologically proven lesions (FNHs, n = 44; HCAs, n = 71) examined with gadoxetic acid-enhanced MRI were retrospectively enrolled (standard of reference: surgical resection, n = 53 patients (lesions: FNHs, n = 37; HCAs, n = 53); biopsy, n = 15 (lesions: FNHs, n = 7; HCAs, n = 18)). Two radiologists evaluated all MR images regarding morphological features as well as the vascular and hepatocyte-specific enhancement in consensus. For the hepatobiliary phase, relative enhancement of the lesions and lesion to liver enhancement were significantly lower for HCAs (mean, 48.7 (±48.4) % and 49.4 (±33.9) %) compared to FNHs (159.3 (±92.5) %; and 151.7 (±79) %; accuracy of 89 % and 90 %, respectively; P < 0.001). Visual strong uptake of FNHs vs. hypointensity of HCAs in the hepatobiliary phase resulted in an accuracy of 92 %. This parameter was superior to all other morphological and dynamic vascular criteria alone and in combination (accuracy, 54-85 %). For differentiation of FNHs and HCAs by means of MRI, gadoxetic acid uptake in the hepatobiliary phase was found to be superior to all other criteria alone and in combination. (orig.)

  7. Betaine and beet molasses enhance L-lactic acid production by Bacillus coagulans.

    Directory of Open Access Journals (Sweden)

    Ke Xu

    Full Text Available Lactic acid is an important chemical with various industrial applications, and it can be efficiently produced by fermentation, in which Bacillus coagulans strains present excellent performance. Betaine can promote lactic acid fermentation as an effective osmoprotectant. Here, positive effect of betaine on fermentation by B. coagulans is revealed. Betaine could enhance lactic acid production by protecting l-LDH activity and cell growth from osmotic inhibition, especially under high glucose concentrations and with poor organic nitrogen nutrients. The fermentation with 0.05 g/L betaine could produce 17.9% more lactic acid compared to the fermentation without betaine. Beet molasses, which is rich in sucrose and betaine, was utilized in a co-feeding fermentation and raised the productivity by 22%. The efficient lactic acid fermentation by B. coagulans is thus developed by using betaine and beet molasses.

  8. Betaine and beet molasses enhance L-lactic acid production by Bacillus coagulans.

    Science.gov (United States)

    Xu, Ke; Xu, Ping

    2014-01-01

    Lactic acid is an important chemical with various industrial applications, and it can be efficiently produced by fermentation, in which Bacillus coagulans strains present excellent performance. Betaine can promote lactic acid fermentation as an effective osmoprotectant. Here, positive effect of betaine on fermentation by B. coagulans is revealed. Betaine could enhance lactic acid production by protecting l-LDH activity and cell growth from osmotic inhibition, especially under high glucose concentrations and with poor organic nitrogen nutrients. The fermentation with 0.05 g/L betaine could produce 17.9% more lactic acid compared to the fermentation without betaine. Beet molasses, which is rich in sucrose and betaine, was utilized in a co-feeding fermentation and raised the productivity by 22%. The efficient lactic acid fermentation by B. coagulans is thus developed by using betaine and beet molasses.

  9. Selection of Anodic Material Used in Electrolytic Process for Producing Hypophosphorous Acid

    Institute of Scientific and Technical Information of China (English)

    Fu Sheng WANG; Bing Kui SONG; Xiao Li HAN; Bao Gui ZHANG

    2004-01-01

    Black lead, Ti-Ru and Ti-PbO2 were used as anode and stainless steel was used as cathode.The electrolytic process of producing hypophosphorous acid with four-compartment electrodialytic cell was studied. The comparison of some factors, such as anodic voltage, product concentration and current efficiency, of black lead, Ti-Ru, and Ti-PbO2 electrodes was conducted. As a result, the Ti-PbO2 electrode is the optimal anode material used, it can be in electrolytic process for producing hypophosphorous acid.

  10. Enhanced butyric acid tolerance and bioproduction by Clostridium tyrobutyricum immobilized in a fibrous bed bioreactor.

    Science.gov (United States)

    Jiang, Ling; Wang, Jufang; Liang, Shizhong; Cai, Jin; Xu, Zhinan; Cen, Peilin; Yang, Shangtian; Li, Shuang

    2011-01-01

    Repeated fed-batch fermentation of glucose by Clostridium tyrobutyricum immobilized in a fibrous bed bioreactor (FBB) was successfully employed to produce butyric acid at a high final concentration as well as to adapt a butyric-acid-tolerant strain. At the end of the eighth fed-batch fermentation, the butyric acid concentration reached 86.9 ± 2.17 g/L, which to our knowledge is the highest butyric acid concentration ever produced in the traditional fermentation process. To understand the mechanism and factors contributing to the improved butyric acid production and enhanced acid tolerance, adapted strains were harvested from the FBB and characterized for their physiological properties, including specific growth rate, acid-forming enzymes, intracellular pH, membrane-bound ATPase and cell morphology. Compared with the original culture used to seed the bioreactor, the adapted culture showed significantly reduced inhibition effects of butyric acid on specific growth rate, cellular activities of butyric-acid-forming enzyme phosphotransbutyrylase (PTB) and ATPase, together with elevated intracellular pH, and elongated rod morphology.

  11. Recombinant host cells and nucleic acid constructs encoding polypeptides having cellulolytic enhancing activity

    Energy Technology Data Exchange (ETDEWEB)

    Schnorr, Kirk; Kramer, Randall

    2017-03-28

    The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

  12. The Histone Deacetylase Inhibitor Valproic Acid Enhances Acquisition, Extinction, and Reconsolidation of Conditioned Fear

    Science.gov (United States)

    Bredy, Timothy W.; Barad, Mark

    2008-01-01

    Histone modifications contribute to the epigenetic regulation of gene expression, a process now recognized to be important for the consolidation of long-term memory. Valproic acid (VPA), used for many years as an anticonvulsant and a mood stabilizer, has effects on learning and memory and enhances the extinction of conditioned fear through its…

  13. ENHANCED DISEASE SUSCEPTIBILITY 1 and SALICYLIC ACID act redundantly to regulate resistance gene-mediated signaling

    Science.gov (United States)

    Resistance (R) protein–associated pathways are well known to participate in defense against a variety of microbial pathogens. Salicylic acid (SA) and its associated proteinaceous signaling components, including enhanced disease susceptibility 1 (EDS1), non–race-specific disease resistance 1 (NDR1), ...

  14. Gallic Acid, the Active Ingredient of Terminalia bellirica, Enhances Adipocyte Differentiation and Adiponectin Secretion.

    Science.gov (United States)

    Makihara, Hiroko; Koike, Yuka; Ohta, Masatomi; Horiguchi-Babamoto, Emi; Tsubata, Masahito; Kinoshita, Kaoru; Akase, Tomoko; Goshima, Yoshio; Aburada, Masaki; Shimada, Tsutomu

    2016-01-01

    Visceral obesity induces the onset of metabolic disorders such as insulin resistance and diabetes mellitus. Adipose tissue is considered as a potential pharmacological target for treating metabolic disorders. The fruit of Terminalia bellirica is extensively used in Ayurvedic medicine to treat patients with diseases such as diabetes mellitus. We previously investigated the effects of a hot water extract of T. bellirica fruit (TB) on obesity and insulin resistance in spontaneously obese type 2 diabetic mice. To determine the active ingredients of TB and their molecular mechanisms, we focused on adipocyte differentiation using mouse 3T3-L1 cells, which are widely used to study adipocyte physiology. We show here that TB enhanced the differentiation of 3T3-L1 cells to mature adipocytes and that one of the active main components was identified as gallic acid. Gallic acid (10-30 µM) enhanced the expression and secretion of adiponectin via adipocyte differentiation and also that of fatty acid binding protein-4, which is the target of peroxisome proliferator-activated receptor gamma (PPARγ), although it does not alter the expression of the upstream genes PPARγ and CCAAT enhancer binding protein alpha. In the PPARγ ligand assay, the binding of gallic acid to PPARγ was undetectable. These findings indicate that gallic acid mediates the therapeutic effects of TB on metabolic disorders by regulating adipocyte differentiation. Therefore, TB shows promise as a candidate for preventing and treating patients with metabolic syndrome.

  15. Gadoxetic Acid (Gd-EOB-DTPA)-Enhanced MRI versus Gadobenate Dimeglumine (Gd-BOPTA)-Enhanced MRI for Preoperatively Detecting Hepatocellular Carcinoma: an Initial Experience

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yu Lri; Kim, Seong Hyun; Kim, Seung Hoon; Choi, Dong Il; Lee, Won Jae; Kim, Hee Jung; Koo, Ji Hyun; Lim, Hyo Keun [Samsung Medical Center, Seoul (Korea, Republic of); Jeon, Yong Hwan [Kangwon National University Hospital, Chuncheon (Korea, Republic of); Lee, Jong Mee; Kim, Min Ju [Korea University College of Medicine, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2010-08-15

    This study was designed to compare the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging (MRI) with gadobenate dimeglumine-enhanced MRI for preoperatively detecting hepatocellular carcinoma (HCC). Eighteen consecutive patients (17 men and one woman, age range: 31-73 years) with 22 HCCs underwent examinations with gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI on a 3.0-Tesla unit. The diagnosis of HCC was established after surgical resection and pathological conformation. Three observers independently reviewed each MR image in a random order on a tumor-by-tumor basis. The diagnostic accuracy of these techniques for the detection of HCC was assessed by performing an alternative free-response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive values were evaluated. The average value of the area under the ROC curve (Az) for gadoxetic acid enhanced MRI (0.887) was not significantly different from the Az (0.899) for gadobenate dimeglumine-enhanced MRI (p > 0.05). The overall sensitivities of gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI were 80% and 83%, respectively, with no significant difference (p > 0.05). The differences of the positive predictive values for the two contrast agents for each observer were not statistically significant (p > 0.05). The diagnostic performance of gadoxetic acid-enhanced MRI and gadobenate dimeglumine-enhanced MRI for preoperatively detecting HCC is quite similar

  16. Enhanced lignin monomer production caused by cinnamic Acid and its hydroxylated derivatives inhibits soybean root growth.

    Directory of Open Access Journals (Sweden)

    Rogério Barbosa Lima

    Full Text Available Cinnamic acid and its hydroxylated derivatives (p-coumaric, caffeic, ferulic and sinapic acids are known allelochemicals that affect the seed germination and root growth of many plant species. Recent studies have indicated that the reduction of root growth by these allelochemicals is associated with premature cell wall lignification. We hypothesized that an influx of these compounds into the phenylpropanoid pathway increases the lignin monomer content and reduces the root growth. To confirm this hypothesis, we evaluated the effects of cinnamic, p-coumaric, caffeic, ferulic and sinapic acids on soybean root growth, lignin and the composition of p-hydroxyphenyl (H, guaiacyl (G and syringyl (S monomers. To this end, three-day-old seedlings were cultivated in nutrient solution with or without allelochemical (or selective enzymatic inhibitors of the phenylpropanoid pathway in a growth chamber for 24 h. In general, the results showed that 1 cinnamic, p-coumaric, caffeic and ferulic acids reduced root growth and increased lignin content; 2 cinnamic and p-coumaric acids increased p-hydroxyphenyl (H monomer content, whereas p-coumaric, caffeic and ferulic acids increased guaiacyl (G content, and sinapic acid increased sinapyl (S content; 3 when applied in conjunction with piperonylic acid (PIP, an inhibitor of the cinnamate 4-hydroxylase, C4H, cinnamic acid reduced H, G and S contents; and 4 when applied in conjunction with 3,4-(methylenedioxycinnamic acid (MDCA, an inhibitor of the 4-coumarate:CoA ligase, 4CL, p-coumaric acid reduced H, G and S contents, whereas caffeic, ferulic and sinapic acids reduced G and S contents. These results confirm our hypothesis that exogenously applied allelochemicals are channeled into the phenylpropanoid pathway causing excessive production of lignin and its main monomers. By consequence, an enhanced stiffening of the cell wall restricts soybean root growth.

  17. Enhancement of the Electrical Properties of CVD-Grown Graphene with Ascorbic Acid Treatment

    Science.gov (United States)

    Tang, Chunmiao; Chen, Zhiying; Zhang, Haoran; Zhang, Yaqian; Zhang, Yanhui; Sui, Yanping; Yu, Guanghui; Cao, Yijiang

    2016-02-01

    Ascorbic acid was used to modify to chemical vapor deposition (CVD)-grown graphene films transferred onto SiO2 substrate. Residual polymer (polymethyl methacrylate), Fe3+, Cl-, H2O, and O2 affected the electrical and thermal properties on graphene during the transfer or device fabrication processes. Exposure of transferred graphene to ascorbic acid resulted in significantly enhanced electrical properties with increased charge carrier mobility. All devices exhibited more than 30% improvement in room temperature carrier mobility in air. The carrier mobility of the treated graphene did not significantly decrease in 21 days. This result can be attributed to electron donation to graphene through the -OH functional group in ascorbic acid that is absorbed in graphene. This work provides a method to enhance the electrical properties of CVD-grown graphene.

  18. The Hip Functional Retrieval after Elective Surgery May Be Enhanced by Supplemented Essential Amino Acids

    Directory of Open Access Journals (Sweden)

    Eleonora Baldissarro

    2016-01-01

    Full Text Available It is not known whether postsurgery systemic inflammation and plasma amino acid abnormalities are still present during rehabilitation of individuals after elective hip arthroplasty (EHA. Sixty subjects (36 females; age 66.58±8.37 years were randomized to receive 14-day oral EAAs (8 g/day or a placebo (maltodextrin. At admission to and discharge from the rehabilitation center, serum C-reactive protein (CRP and venous plasma amino acid concentrations were determined. Post-EHA hip function was evaluated by Harris hip score (HHS test. Ten matched healthy subjects served as controls. At baseline, all patients had high CRP levels, considerable reduction in several amino acids, and severely reduced hip function (HHS 40.78±2.70 scores. After treatment, inflammation decreased both in the EAA group and in the placebo group. Only EAA patients significantly improved their levels of glycine, alanine, tyrosine, and total amino acids. In addition, they enhanced the rate of hip function recovery (HHS (from baseline 41.8±1.15 to 76.37±6.6 versus baseline 39.78±4.89 to 70.0±7.1 in placebo one; p=0.006. The study documents the persistence of inflammation and plasma amino acid abnormalities in post-EHA rehabilitation phase. EAAs enhance hip function retrieval and improve plasma amino acid abnormalities.

  19. The Hip Functional Retrieval after Elective Surgery May Be Enhanced by Supplemented Essential Amino Acids

    Science.gov (United States)

    Baldissarro, Eleonora; Aquilani, Roberto; Boschi, Federica; Baiardi, Paola; Iadarola, Paolo; Fumagalli, Marco; Pasini, Evasio; Verri, Manuela; Dossena, Maurizia; Gambino, Arianna; Cammisuli, Sharon; Viglio, Simona

    2016-01-01

    It is not known whether postsurgery systemic inflammation and plasma amino acid abnormalities are still present during rehabilitation of individuals after elective hip arthroplasty (EHA). Sixty subjects (36 females; age 66.58 ± 8.37 years) were randomized to receive 14-day oral EAAs (8 g/day) or a placebo (maltodextrin). At admission to and discharge from the rehabilitation center, serum C-reactive protein (CRP) and venous plasma amino acid concentrations were determined. Post-EHA hip function was evaluated by Harris hip score (HHS) test. Ten matched healthy subjects served as controls. At baseline, all patients had high CRP levels, considerable reduction in several amino acids, and severely reduced hip function (HHS 40.78 ± 2.70 scores). After treatment, inflammation decreased both in the EAA group and in the placebo group. Only EAA patients significantly improved their levels of glycine, alanine, tyrosine, and total amino acids. In addition, they enhanced the rate of hip function recovery (HHS) (from baseline 41.8 ± 1.15 to 76.37 ± 6.6 versus baseline 39.78 ± 4.89 to 70.0 ± 7.1 in placebo one; p = 0.006). The study documents the persistence of inflammation and plasma amino acid abnormalities in post-EHA rehabilitation phase. EAAs enhance hip function retrieval and improve plasma amino acid abnormalities. PMID:27110573

  20. Remediation of TCE-contaminated groundwater using acid/BOF slag enhanced chemical oxidation.

    Science.gov (United States)

    Tsai, T T; Kao, C M; Wang, J Y

    2011-04-01

    The objective of this study was to evaluate the potential of applying acid/H(2)O(2)/basic oxygen furnace slag (BOF slag) and acid/S(2)O(8)(2-)/BOF slag systems to enhance the chemical oxidation of trichloroethylene (TCE)-contaminated groundwater. Results from the bench-scale study indicate that TCE oxidation via the Fenton-like oxidation process can be enhanced with the addition of BOF slag at low pH (pH=2-5.2) and neutral (pH=7.1) conditions. Because the BOF slag has iron abundant properties (14% of FeO and 6% of Fe(2)O(3)), it can be sustainably reused for the supplement of iron minerals during the Fenton-like or persulfate oxidation processes. Results indicate that higher TCE removal efficiency (84%) was obtained with the addition of inorganic acid for the activation of Fenton-like reaction compared with the experiments with organic acids addition (with efficiency of 10-15% lower) (BOF slag=10gL(-1); initial pH=5.2). This could be due to the fact that organic acids would compete with TCE for available oxidants. Results also indicate that the pH value had a linear correlation with the observed first-order decay constant of TCE, and thus, lower pH caused a higher TCE oxidation rate.

  1. Optimization of culture media for enhancing gamma-linolenic acid production by Mucor hiemalis

    Directory of Open Access Journals (Sweden)

    Mina Mohammadi Nasr

    2016-03-01

    Full Text Available Introduction: g-linolenic acid is an essential fatty acid in human nutrition. In the present study, production of g-linolenic acid by Mucor hiemalis PTCC 5292 was evaluated in submerged fermentation. Materials and methods: The fermentation variables were chosen according to the fractional factorial design and further optimized via full factorial method. Four significant variables, glucose, peptone, ammonium nitrate and pH were selected for the optimization studies. The design consisted of total 16 runs consisting of runs at two levels for each factor with three replications of the center points. Results: The analysis of variance and three-dimensional response surface plot of effects indicated that variables were regarded to be significant for production of g-linolenic acid by Mucor hiemalis. Results indicated that fermentation at the optimum conditions (100 g/l glucose concentration; 1 g/l peptone; 1 g/l ammonium nitrate, and pH of 4.5 enhanced the g-linolenic acid production up to 709 mg/l. Discussion and conclusion: The results of this study indicated that higher g-linolenic acid yield can be achieved in a simple medium at high glucose and ammonium nitrate, low peptone concentrations and acidic pH by Mucor hiemalis PTCC 5292. This simple and low cost optimization condition of culture media can be applied for g-linolenic acid production at higher scale for pharmaceutical and nutritional industries. 

  2. Enhanced succinic acid production in Aspergillus saccharolyticus by heterologous expression of fumarate reductase from Trypanosoma brucei.

    Science.gov (United States)

    Yang, Lei; Lübeck, Mette; Ahring, Birgitte K; Lübeck, Peter S

    2016-02-01

    Aspergillus saccharolyticus exhibits great potential as a cell factory for industrial production of dicarboxylic acids. In the analysis of the organic acid profile, A. saccharolyticus was cultivated in an acid production medium using two different pH conditions. The specific activities of the enzymes, pyruvate carboxylase (PYC), malate dehydrogenase (MDH), and fumarase (FUM), involved in the reductive tricarboxylic acid (rTCA) branch, were examined and compared in cells harvested from the acid production medium and a complete medium. The results showed that ambient pH had a significant impact on the pattern and the amount of organic acids produced by A. saccharolyticus. The wild-type strain produced higher amount of malic acid and succinic acid in the pH buffered condition (pH 6.5) compared with the pH non-buffered condition. The enzyme assays showed that the rTCA branch was active in the acid production medium as well as the complete medium, but the measured enzyme activities were different depending on the media. Furthermore, a soluble NADH-dependent fumarate reductase gene (frd) from Trypanosoma brucei was inserted and expressed in A. saccharolyticus. The expression of the frd gene led to an enhanced production of succinic acid in frd transformants compared with the wild-type in both pH buffered and pH non-buffered conditions with highest amount produced in the pH buffered condition (16.2 ± 0.5 g/L). This study demonstrates the feasibility of increasing succinic acid production through the cytosolic reductive pathway by genetic engineering in A. saccharolyticus.

  3. Study on the Enhancement of Proton Affinity by N-Diisopropyloxy Phosphorylation of Amino Acid in Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    With introduction of a diisopropyloxy phosphoryl group into the N terminal of amino acids, it was found that proton affinity (PA) of amino acid was enhanced in mass spectrometry. Density functional theory calculations showed that the energy for protonation of DIPP-amino acid is lower than that of amino acid, which means PA of DIPP-AA is higher than that of corresponding amino acid. These results, coincident with our empirical results, offer a useful interpretation of experimental observations.

  4. Enhanced rosmarinic acid production in cultured plants of two species of Mentha.

    Science.gov (United States)

    Roy, Debleena; Mukhopadhyay, Sandip

    2012-11-01

    In the present investigation an attempt has been made to enhance rosmarinic acid level in plants, grown in vitro, of 2 species of Mentha in presence of 2 precursors in the nutrient media during culture. For in vitro culture establishment and shoot bud multiplication, MS basal media were used supplemented with different concentrations and combinations of different growth regulator like NAA (alpha-napthaleneacetic acid), BAP (6-benzylaminopurine). The medium containing NAA (0.25 mg/L) and BAP (2.5 mg/L) gave the highest potentiality of shoot formation (average 58.0 numbers of shoots) per explant for Mentha piperita L. and the medium containing BAP (2.0 mg/L) gave the highest potentiality of shoot (average 19.2 numbers of shoots) formation per explant for Mentha arvensis L. The complete plants were regenerated in above mentioned media after 8 weeks of subculture. For in vitro enhancement of rosmarinic acid production, the 2 precursors tyrosine (Tyr) and phenylalanine (Phe) were added in the nutrient media at different levels (0.5 mg/L to 15.0 mg/L). Tyrosine was found to be very effective for augmenting rosmarinic acid content in Mentha piperita L. It nearly increased the production up to 1.77 times. In case of Mentha arvensis L., phenylalanine significantly affected the production of rosmarinic acid and the production was nearly 2.03 times more than the control. No significant increase in biomass was observed after addition of these precursors indicating that the added amino acids acting as precursors for rosmarinic acid synthesis were readily utilized in producing rosmarinic acid without promoting growth. Total protein profile also revealed the presence of a specific band in polyacrylamide gel electrophoresis.

  5. Nanoparticle-enhanced fluorescence emission for non-separation assays of carbohydrates using a boronic acid-alizarin complex.

    Science.gov (United States)

    Li, Qianjin; Kamra, Tripta; Ye, Lei

    2016-03-01

    Addition of crosslinked polymer nanoparticles into a solution of a 3-nitrophenylboronic acid-alizarin complex leads to significant enhancement of fluorescence emission. Using the nanoparticle-enhanced boronic acid-alizarin system has improved greatly the sensitivity and extended the dynamic range of separation-free fluorescence assays for carbohydrates.

  6. Genetic analysis of pathway regulation for enhancing branched-chain amino acid biosynthesis in plants

    KAUST Repository

    Chen, Hao

    2010-08-01

    The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that play critical roles in animal growth and development. Animals cannot synthesize these amino acids and must obtain them from their diet. Plants are the ultimate source of these essential nutrients, and they synthesize BCAAs through a conserved pathway that is inhibited by its end products. This feedback inhibition has prevented scientists from engineering plants that accumulate high levels of BCAAs by simply over-expressing the respective biosynthetic genes. To identify components critical for this feedback regulation, we performed a genetic screen for Arabidopsis mutants that exhibit enhanced resistance to BCAAs. Multiple dominant allelic mutations in the VALINE-TOLERANT 1 (VAT1) gene were identified that conferred plant resistance to valine inhibition. Map-based cloning revealed that VAT1 encodes a regulatory subunit of acetohydroxy acid synthase (AHAS), the first committed enzyme in the BCAA biosynthesis pathway. The VAT1 gene is highly expressed in young, rapidly growing tissues. When reconstituted with the catalytic subunit in vitro, the vat1 mutant-containing AHAS holoenzyme exhibits increased resistance to valine. Importantly, transgenic plants expressing the mutated vat1 gene exhibit valine tolerance and accumulate higher levels of BCAAs. Our studies not only uncovered regulatory characteristics of plant AHAS, but also identified a method to enhance BCAA accumulation in crop plants that will significantly enhance the nutritional value of food and feed. © 2010 Blackwell Publishing Ltd.

  7. A new self-emulsifying formulation of mefenamic acid with enhanced drug dissolution

    Directory of Open Access Journals (Sweden)

    Pornsak Sriamornsak

    2015-04-01

    Full Text Available To enhance the dissolution of poorly soluble mefenamic acid, self-emulsifying formulation (SEF, composing of oil, surfactant and co-surfactant, was formulated. Among the oils and surfactants studied, Imwitor® 742, Tween® 60, Cremophore® EL and Transcutol® HP were selected as they showed maximal solubility to mefenamic acid. The ternary phase diagram was constructed to find optimal concentration that provided the highest drug loading. The droplet size after dispersion and drug dissolution of selected formulations were investigated. The results showed that the formulation containing Imwitor® 742, Tween® 60 and Transcutol® HP (10:30:60 can encapsulate high amount of mefenamic acid. The dissolution study demonstrated that, in the medium containing surfactant, nearly 100% of mefenamic acid were dissolved from SEF within 5 min while 80% of drugs were dissolved from the commercial product in 45 min. In phosphate buffer (without surfactant, 80% of drug were dissolved from the developed SEF within 5 min while only about 13% of drug were dissolved in 45 min, from the commercial product. The results suggested that the SEF can enhance the dissolution of poorly soluble drug and has a potential to enhance drug absorption and improve bioavailability of drug.

  8. The enhancement of pipemidic acid permeation into the pig urinary bladder wall.

    Science.gov (United States)

    Kerec, M; Svigelj, V; Bogataj, M; Mrhar, A

    2002-06-20

    The influence of interactions between polycarbophil and calcium on a model drug permeation into the pig urinary bladder wall was investigated. Pipemidic acid was used as a model drug. One percent w/v polycarbophil dispersion significantly increases the permeation of pipemidic acid into the urinary bladder wall. The enhanced absorption of pipemidic acid caused by polycarbophil is significantly less pronounced in polycarbophil dispersions containing calcium. The enhancement of pipemidic acid permeation into the urinary bladder wall could be due to the opening of tight junctions, which causes higher paracellular permeability. In the case of polycarbophil dispersion with calcium some carboxylic groups of polymer are already occupied with calcium, present in the dispersions. As a consequence extracellular calcium binds to polycarbophil in lower extent if compared with polycarbophil dispersion without calcium and transport is increased to a lesser degree. We concluded that the mechanism of drug absorption enhancement caused by polycarbophil could be similar for urinary bladder as described in the literature for intestinal mucosa.

  9. Intrahepatic mass-forming cholangiocarcinoma: prognostic value of preoperative gadoxetic acid-enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Jieun; Chung, Yong Eun; Kim, Myeong-Jin; Choi, Jin-Young [Yonsei University, College of Medicine, Department of Radiology, Research Institute of Radiological Science, Seoul (Korea, Republic of); Nahm, Ji Hae; Park, Young Nyun [Yonsei University, College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Kim, Ha Yan [Yonsei University, College of Medicine, Biostatistics Collaboration Unit, Severance Hospital, Seoul (Korea, Republic of); Kim, Kyung-Sik [Yonsei University, College of Medicine, Department of General Surgery, Seoul (Korea, Republic of)

    2016-02-15

    To assess whether gadoxetic acid-enhanced MRI could be used as a prognostic factor for intrahepatic mass-forming cholangiocarcinomas (IMCCs). Forty-one patients with pathologically proven IMCCs who underwent preoperative gadoxetic acid-enhanced MRI were included. The signal intensity of the IMCCs on hepatobiliary phase (HBP) MRI was qualitatively analyzed by two radiologists, and categorized into intermediate or hypointense groups. Analysis of clinicopathological prognostic factors and correlations of imaging and histology were also performed. Survival time and time to recurrence (TTR) were analyzed. Of the 41 IMCCs, 23 were in the intermediate group and 18 were in the hypointense group on HBP MRI. IMCCs in the intermediate group were associated with shorter survival time (P = 0.048) and TTR (P = 0.002) than the IMCCs of the hypointense group. Only the intermediate group on HBP MRI had a significantly shorter TTR on multivariate analysis (P = 0.012). The IMCCs of the intermediate group showed a tendency for more abundant tumour fibrous stroma than those of the hypointense group (P = 0.027). The enhancement of IMCCs on HBP gadoxetic acid-enhanced MRI appears to correlate with tumour aggressiveness and outcomes due to the tumour fibrous stromal component. Thus, HBP images could be a useful prognostic factor for IMCCs after surgery. (orig.)

  10. Electrochemical analysis of ion-exchange membranes with respect to a possible use in electrodialytic decontamination of soil polluted with heavy metals

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Laursen, Søren;

    1997-01-01

    Transport numbers in different metal chloride solutions were estimated using the emf method for two ion-exchange membranes: Ionics CR67 HMR412 (cation-exchange membrane) and Ionics AR204 SXRA 7639 (anion-exchange membrane). The cation-exchange membrane was found to work nearly ideally for Na......Cl and CaCl2 solutions even at high concentrations, whereas deviation from ideality was seen for ZnCl2 and CuCl2 solutions. The anion-exchange membrane showed transport numbers for the anion around 0.95 for NaCl, CaCl2 and ZnCl2 solutions for the concentration range investigated. Electrodialytic desalting...

  11. Screening the possibility for removing cadmium and other heavy metals from wastewater sludge and bio-ashes by an electrodialytic method

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Pedersen, Anne Juul; Hansen, Henrik K.

    2007-01-01

    in wastewater sludge and bio-ashes (straw and wood) using an electrodialytic method. The waste products were treated as stirred suspensions. During the remediation the suspension was acidified from water splitting at the anion exchange membrane and the acidification mobilized Cd that was removed......Both wastewater sludge and fly ash from combustion of biomass (bio-ash) have traditionally been applied to agricultural land in Denmark. However, Cd concentrations often exceed limiting values. The present study is a preliminary investigation of the possibility for reducing the Cd concentration...... to the electrode compartments. Even though the matrices were very different the remediation was successful in all cases. After treatment the Cd concentration in the ashes allowed for spreading at agricultural land and the limiting concentration of 0.8mgCd/kg for the wastewater sludge was almost reached (0.84 and 0...

  12. Enhanced Synthesis of Alkyl Amino Acids in Miller's 1958 H2S Experiment

    Science.gov (United States)

    Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, James P.; Glavin, Daniel P.; Lazcano, Antonio; Bada, Jeffrey L.

    2011-01-01

    Stanley Miller's 1958 H2S-containing experiment, which included a simulated prebiotic atmosphere of methane (CH4), ammonia (NH3), carbon dioxide (CO2), and hydrogen sulfide (H2S) produced several alkyl amino acids, including the alpha-, beta-, and gamma-isomers of aminobutyric acid (ABA) in greater relative yields than had previously been reported from his spark discharge experiments. In the presence of H2S, aspariic and glutamic acids could yield alkyl amino acids via the formation of thioimide intermediates. Radical chemistry initiated by passing H2S through a spark discharge could have also enhanced alkyl amino acid synthesis by generating alkyl radicals that can help form the aldehyde and ketone precursors to these amino acids. We propose mechanisms that may have influenced the synthesis of certain amino acids in localized environments rich in H2S and lightning discharges, similar to conditions near volcanic systems on the early Earth, thus contributing to the prebiotic chemical inventory of the primordial Earth.

  13. Enhancing the functionality of biobased polyester coating resins through modification with citric acid.

    Science.gov (United States)

    Noordover, Bart A J; Duchateau, Robbert; van Benthem, Rolf A T M; Ming, Weihua; Koning, Cor E

    2007-12-01

    Citric acid (CA) was evaluated as a functionality-enhancing monomer in biobased polyesters suitable for coating applications. Model reactions of CA with several primary and secondary alcohols and diols, including the 1,4:3,6-dianhydrohexitols, revealed that titanium(IV) n-butoxide catalyzed esterification reactions involving these compounds proceed at relatively low temperatures, often via anhydride intermediates. Interestingly, the facile anhydride formation from CA at temperatures around CA's melting temperature ( T m = 153 degrees C) proved to be crucial in modifying sterically hindered secondary hydroxyl end groups. OH-functional polyesters were reacted with CA in the melt between 150 and 165 degrees C, yielding slightly branched carboxylic acid functional materials with strongly enhanced functionality. The acid/epoxy curing reaction of the acid-functional polymers was simulated with a monofunctional glycidyl ether. Finally, the CA-modified polyesters were applied as coatings, using conventional cross-linking agents. The formulations showed rapid curing, resulting in chemically and mechanically stable coatings. These results demonstrate that citric acid can be applied in a new way, making use of its anhydride formation to functionalize OH-functional polyesters, which is an important new step toward fully biobased coating systems.

  14. Arabidopsis ENHANCED DISEASE SUSCEPTIBILITY1 promotes systemic acquired resistance via azelaic acid and its precursor 9-oxo nonanoic acid.

    Science.gov (United States)

    Wittek, Finni; Hoffmann, Thomas; Kanawati, Basem; Bichlmeier, Marlies; Knappe, Claudia; Wenig, Marion; Schmitt-Kopplin, Philippe; Parker, Jane E; Schwab, Wilfried; Vlot, A Corina

    2014-11-01

    Systemic acquired resistance (SAR) is a form of inducible disease resistance that depends on salicylic acid and its upstream regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). Although local Arabidopsis thaliana defence responses activated by the Pseudomonas syringae effector protein AvrRpm1 are intact in eds1 mutant plants, SAR signal generation is abolished. Here, the SAR-specific phenotype of the eds1 mutant is utilized to identify metabolites that contribute to SAR. To this end, SAR bioassay-assisted fractionation of extracts from the wild type compared with eds1 mutant plants that conditionally express AvrRpm1 was performed. Using high-performance liquid chromatography followed by mass spectrometry, systemic immunity was associated with the accumulation of 60 metabolites, including the putative SAR signal azelaic acid (AzA) and its precursors 9-hydroperoxy octadecadienoic acid (9-HPOD) and 9-oxo nonanoic acid (ONA). Exogenous ONA induced SAR in systemic untreated leaves when applied at a 4-fold lower concentration than AzA. The data suggest that in planta oxidation of ONA to AzA might be partially responsible for this response and provide further evidence that AzA mobilizes Arabidopsis immunity in a concentration-dependent manner. The AzA fragmentation product pimelic acid did not induce SAR. The results link the C9 lipid peroxidation products ONA and AzA with systemic rather than local resistance and suggest that EDS1 directly or indirectly promotes the accumulation of ONA, AzA, or one or more of their common precursors possibly by activating one or more pathways that either result in the release of these compounds from galactolipids or promote lipid peroxidation.

  15. Amino-Functional Polybenzimidazole Blends with Enhanced Phosphoric Acid Mediated Proton Conductivity as Fuel Cell Electrolytes

    DEFF Research Database (Denmark)

    Aili, David; Javakhishvili, Irakli; Han, Junyoung;

    2016-01-01

    A new amino-functional polybenzimidazole copolymer is synthesized by homogeneous solution condensation polymerization from a novel monomer, N,N′-bis (2,4-diaminophenyl)-1,3-diaminopropane. The copolymer readily dissolves in organic solvents and shows good film forming characteristics. To balance...... the phosphoric acid uptake and to obtain mechanically robust membranes, the amino-functional polybenzimidazole derivative is blended with high molecular weight poly [2,2′-(m-phenylene)-5,5′-bisbenzimidazole] at different ratios. Due to the high acid uptake, the homogenous blend membranes show enhanced proton...

  16. Morphology-dependent Electrochemical Enhancements of Porous Carbon as Sensitive Determination Platform for Ascorbic Acid, Dopamine and Uric Acid

    Science.gov (United States)

    Cheng, Qin; Ji, Liudi; Wu, Kangbing; Zhang, Weikang

    2016-02-01

    Using starch as the carbon precursor and different-sized ZnO naoparticles as the hard template, a series of porous carbon materials for electrochemical sensing were prepared. Experiments of scanning electron microscopy, transmission electron microscopy and Nitrogen adsorption-desorption isotherms reveal that the particle size of ZnO has big impacts on the porous morphology and surface area of the resulting carbon materials. Through ultrasonic dispersion of porous carbon and subsequent solvent evaporation, different sensing interfaces were constructed on the surface of glassy carbon electrode (GCE). The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) were studied. On the surface of porous carbon materials, the accumulation efficiency and electron transfer ability of AA, DA and UA are improved, and consequently their oxidation signals enhance greatly. Moreover, the interface enhancement effects of porous carbon are also controlled by the particle size of hard template. The constructed porous carbon interface displays strong signal amplification ability and holds great promise in constructing a sensitive platform for the simultaneous determination of AA, DA and UA.

  17. Fatty Acid Incubation of Myotubues from Humans with Type 2 Diabetes Leads to Enhanced Release of Beta Oxidation Products Due to Impaired Fatty Acid Oxidation

    DEFF Research Database (Denmark)

    Wensaas, Andreas J; Rustan, Arild C; Just, Marlene;

    2008-01-01

    these processes. Research Design and Methods: We examined fatty acid and glucose metabolism, and gene expression in cultured human skeletal muscle cells from control and T2D individuals after four days preincubation with EPA or TTA. Results: T2D myotubes exhibited reduced formation of CO(2) from palmitic acid (PA......Objective: Increased availability of fatty acids is important for accumulation of intracellular lipids and development of insulin resistance in human myotubes. It is unknown whether different types of fatty acids like eicosapentaenoic acid (EPA) or tetradecylthioacetic acid (TTA) influence....... EPA markedly enhanced TAG accumulation in myotubes, more pronounced in T2D cells. TAG accumulation and fatty acid oxidation were inversely correlated only after EPA preincubation, and total level of acyl-CoA was reduced. Glucose oxidation (CO(2) formation) was enhanced and lactate production decreased...

  18. Electrodialytic remediation of polychlorinated biphenyls contaminated soil with iron nanoparticles and two different surfactants

    DEFF Research Database (Denmark)

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.

    2014-01-01

    nanoparticles (nZVI) could be a competitive alternative to the commonly adapted solutions of incineration or landfilling. Surfactants can enhance the PCB desorption, dechlorination, and the contaminated soil cleanup. In this work, two different surfactants (saponin and Tween 80) were tested to enhance PCB...... desorption and removal from a soil sampled at a polluted site, in a two-compartment cell where the soil was stirred in a slurry with 1% surfactant, 10mL of nZVI commercial suspension, and a voltage gradient of 1Vcm(-1). The highest PCB removal was obtained with saponin. Higher chlorinated PCB congeners...... (penta, hexa, hepta and octachlorobiphenyl) showed removal percentages between 9% and 96%, and the congeners with highest removal were PCB138, PCB153 and PCB180. The use of low level direct current enhanced PCB removal, especially with saponin. Electrodechlorination of PCB with surfactants and n...

  19. Intraluminal duodenal diverticulum: CT and gadoxetic acid-enhanced MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Myeong; Lee, Nam Kyung; Kim, Suk; Kim, Dong Uk; Kim, Tae Un [Dept. of Radiology, Pusan National University Hospital, Pusan National University School of Medicine, Busan (Korea, Republic of)

    2015-03-15

    Intraluminal duodenal diverticulum (IDD) is a rare congenital anomaly. IDD can become symptomatic in 20% to 25% of cases when complicated by intestinal obstruction, pancreatitis, or hemorrhage. We report the case of a 21-year-old female presenting with IDD mimicking duodenoduodenal intussusception. We describe the imaging features of IDD on the gadoxetic acid-enhanced magnetic resonance image as well as computed tomography.

  20. Enhanced succinic acid production from corncob hydrolysate by microbial electrolysis cells.

    Science.gov (United States)

    Zhao, Yan; Cao, Weijia; Wang, Zhen; Zhang, Bowen; Chen, Kequan; Ouyang, Pingkai

    2016-02-01

    In this study, Actinobacillus succinogenes NJ113 microbial electrolysis cells (MECs) were used to enhance the reducing power responsible for succinic acid production from corncob hydrolysate. During corncob hydrolysate fermentation, electric MECs resulted in a 1.31-fold increase in succinic acid production and a 1.33-fold increase in the reducing power compared with those in non-electric MECs. When the hydrolysate was detoxified by combining Ca(OH)2, NaOH, and activated carbon, succinic acid production increased from 3.47 to 6.95 g/l. Using a constant potential of -1.8 V further increased succinic acid production to 7.18 g/l. A total of 18.09 g/l of succinic acid and a yield of 0.60 g/g total sugar were obtained after a 60-h fermentation when NaOH was used as a pH regulator. The improved succinic acid yield from corncob hydrolysate fermentation using A. succinogenes NJ113 in electric MECs demonstrates the great potential of using biomass as a feedstock to cost-effectively produce succinate.

  1. Enhancement of taxol-induced apoptosis by inhibition of NF-κB with ursorlic acid

    Science.gov (United States)

    Li, Yunlong; Xing, Da

    2007-05-01

    Taxol is known to inhibit cell growth and triggers significant apoptosis in various cancer cells, and activation of proliferation factor NF-κB during Taxol-induced apoptosis is regarded as a main reason resulting in tumor cells resistance to Taxol. It has been found that ursorlic acid can inhibit the activation of NF-κB. In order to study whether ursorlic acid can enhance the Taxol-induced apoptosis, we use fluorescence resonance energy transfer (FRET) technique and probe SCAT3 to compare the difference of caspase-3 activation between Taxol alone and Taxol combined ursorlic acid. With laser scanning confocal microscopy, we find that ursorlic acid, a nontoxic food component, sensitizes ASTC-a-1 cells more efficiently to Taxol-induced apoptosis by advanced activation of caspase 3. The result also suggests that there would be a synergistic effect between Taxol and ursorlic acid, and the more detailed mechanism of synergistic effect needs to be clarified further, such as the correlations among NF-κB, Akt, caspase 8, which leads to the advanced activation of caspase 3 during combined treatment of Taxol and ursorlic acid. Moreover, this may be a new way to improve Taxol-dependent tumor therapy.

  2. Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids

    Science.gov (United States)

    Li, Yingchao; Jia, Ru; Al-Mahamedh, Hussain H.; Xu, Dake; Gu, Tingyue

    2016-01-01

    Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. D-Amino acids are naturally occurring. Our previous work demonstrated that some D-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm D-tyrosine and 100 ppm D-methionine used separately successfully mitigated the Desulfovibrio vulgaris biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of D-methionine, D-tyrosine, D-leucine, and D-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual D-amino acids were inadequate for the biofilm consortia. PMID:27379039

  3. Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids.

    Science.gov (United States)

    Li, Yingchao; Jia, Ru; Al-Mahamedh, Hussain H; Xu, Dake; Gu, Tingyue

    2016-01-01

    Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. D-Amino acids are naturally occurring. Our previous work demonstrated that some D-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm D-tyrosine and 100 ppm D-methionine used separately successfully mitigated the Desulfovibrio vulgaris biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of D-methionine, D-tyrosine, D-leucine, and D-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual D-amino acids were inadequate for the biofilm consortia.

  4. Surface modification of activated carbon for enhanced adsorption of perfluoroalkyl acids from aqueous solutions.

    Science.gov (United States)

    Zhi, Yue; Liu, Jinxia

    2016-02-01

    The objective of the research was to examine the effect of increasing carbon surface basicity on uptake of perfluorooctane sulfonic (PFOS) and carboxylic acids (PFOA) by activated carbon. Granular activated carbons made from coal, coconut shell, wood, and phenolic-polymer-based activated carbon fibers were modified through high-temperature and ammonia gas treatments to facilitate systematical evaluation of the impact of basicity of different origins. Comparison of adsorption isotherms and adsorption distribution coefficients showed that the ammonia gas treatment was more effective than the high-temperature treatment in enhancing surface basicity. The resultant higher point of zero charges and total basicity (measured by total HCl uptake) correlated with improved adsorption affinity for PFOS and PFOA. The effectiveness of surface modification to enhance adsorption varied with carbon raw material. Wood-based carbons and activated carbon fibers showed enhancement by one to three orders of magnitudes while other materials could experience reduction in adsorption towards either PFOS or PFOA.

  5. Electrodialytic extraction of phosphorus from ash of low-temperature gasification of sewage sludge

    DEFF Research Database (Denmark)

    Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2015-01-01

    was from gasification of sewage sludge where P was precipitated with Fe and Al salts, from which it was possible to extract up to 26% of the P. The other ash was from co-gasification of a mixture of biologically precipitated sewage sludge and wheat straw pellets. More promising results were obtained...... with this ash, as up to 90% of the P was extracted from the ashes. For both ashes, P was extracted by ED in acidic aqueous solutions with ratios of Fe, Al and each heavy metal to P considerably below the values found in the initial ashes. Therefore, the 2-compartment ED cell technology was proved as possible...

  6. Enhancement of Esterification of Propionic Acid with Isopropyl Alcohol by Pervaporation Reactor

    Directory of Open Access Journals (Sweden)

    Ajit P. Rathod

    2014-01-01

    Full Text Available With increasing cost of raw materials and energy, there is an increasing inclination of chemical process industries toward new processes that result in lesser waste generation, greater efficiency, and substantial yield of the desired products. Esterification is a chemical reaction in which two reactants carboxylic acid and alcohol react to form an ester and water. This reaction is a reversible reaction and the equilibrium conversion can be altered by varying the process parameters. Pervaporation reactor can enhance the conversion by shifting the equilibrium of reversible esterification reactions. Polyvinyl alcohol-polyether sulfone composite hydrophilic membrane was used for pervaporation-assisted esterification of propionic acid with isopropyl alcohol. The experiments were carried out in the presence of sulphuric acid as a catalyst at 50°C to 80°C with various reactants ratios. The esterification was carried out for catalyst loadings of 0.089 kmol/m3 to 0.447 kmol/m3. The molar ratios of isopropyl to propionic acid used for the experiment were 1 to 1.5. Maximum conversion was obtained for the ratio of 1.4. Also effect of other parameters such as process temperature and catalyst concentration was discussed. It was found that the use of pervaporation reactor increased the conversion of the propionic acid considerably.

  7. Combined humic acid adsorption and enhanced Fenton processes for the treatment of naphthalene dye intermediate wastewater.

    Science.gov (United States)

    Gu, Lin; Zhu, Nanwen; Wang, Liang; Bing, Xiaoxiao; Chen, Xiaoliang

    2011-12-30

    In this work, an humic acid adsorption with an enhanced Fenton oxidation was employed to treat the real effluent originating from the 1-diazo-2-naphthol-4-sulfonic acid (1,2,4-Acid) production plant. In a first step, humic acid with MgSO(4) was selected as adsorbent and precipitant for physicochemical pretreatment, the synergetic effect had led to 39% of COD removal and 89% of colour removal. A multi-staged Fenton oxidation process with inner circulation was introduced subsequently. The TOC, COD, 1,2,4-Acid, NH(4)(+)-N, SS and colour were reduced from 3024 mg/L, 12,780 mg/L, 9103 mg/L, 110 mg/L, 240 mg/L and 25,600 (multiple) to 46 mg/L, 210 mg/L, 21 mg/L, 16 mg/L, 3 mg/L and 25 through the combined process, respectively. Hydrogen peroxide consumed per kg COD had saved up to 36% when two-staged Fenton process with inner circulation (flow-back to influent ratio: 3) was applied. Influence of H(2)O(2) concentration, flow-back to influent ratio and staged Fenton mode were investigated in detail in order to find out the optimal operating parameters. The kinetics of 1,2,4-Acid degradation by two-staged Fenton process was investigated. The evolution of the main intermediates during the degradation process was conducted using the LC-(ESI)-TOF-MS technique, and the results showed a staged degradation pathway from the ring opening of naphthalene compounds to the formation of benzene compounds and carboxyl acids. The combined process had been proved effective in both technical and economic aspects.

  8. Application of Microbial Products to Promote Electrodialytic Remediation of Heavy Metal Contaminated Soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland

    2006-01-01

    influences the remediation-time negatively. EDR remediation of fine grained, inorganic soils was documented to be feasible when the Pb is not associated with extremely stable compounds. The potential of treating other fine-grained materials in a suspended version of EDR had at this time been demonstrated...... of the lack of relevance to treatment of Pb-contaminated soil. Autotrophic leaching, which is leaching by acidophilic, autotrophic microorganisms obtaining energy by oxidation of elemental sulfur, was shown to induce acidification of soil-fines in suspension, but removal of Pb from the treated soil...... is optimal with distilled water as solvent. Consequently addition of nitric acid is recommended in cases where the removal rate is considered important, while suspension in pure water is recommended in situations where the energy expenditure and the chemical costs are limiting factors. Considering...

  9. β-cyclocitral upregulates salicylic acid signalling to enhance excess light acclimation in Arabidopsis.

    Science.gov (United States)

    Lv, Feifei; Zhou, Jun; Zeng, Lizhang; Xing, Da

    2015-08-01

    β-cyclocitral (β-CC), a volatile oxidized derivative of β-carotene, can upregulate the expression of defence genes to enhance excess light (EL) acclimation. However, the signalling cascades underlying this process remain unclear. In this study, salicylic acid (SA) is involved in alleviating damage to promote β-CC-enhanced EL acclimation. In early stages of EL illumination, β-CC pretreatment induced SA accumulation and impeded reactive oxygen species (ROS) production in the chloroplast. A comparative analysis of two SA synthesis pathways in Arabidopsis revealed that SA concentration mainly increased via the isochorismate synthase 1 (ICS1)-mediated isochorismate pathway, which depended on essential regulative function of enhanced disease susceptibility 1 (EDS1). Further results showed that, in the process of β-CC-enhanced EL acclimation, nuclear localization of nonexpressor of pathogenesis-related genes 1 (NPR1) was regulated by SA accumulation and NPR1 induced subsequent transcriptional reprogramming of gluthathione-S-transferase 5 (GST5) and GST13 implicated in detoxification. In summary, β-CC-induced SA synthesis contributes to EL acclimation response by decreasing ROS production in the chloroplast, promoting nuclear localization of NPR1, and upregulating GST transcriptional expression. This process is a possible molecular regulative mechanism of β-CC-enhanced EL acclimation.

  10. Self-assembling micelle-like nanoparticles with detachable envelopes for enhanced delivery of nucleic acid therapeutics.

    Science.gov (United States)

    Battogtokh, Gantumur; Ko, Young Tag

    2014-03-01

    In spite of the great potential of nucleic acids as therapeutic agents, the clinical application of nucleic acid therapeutics requires the development of effective systemic delivery strategies. In an effort to develop effective nucleic acid delivery systems suitable for clinical application, we previously reported a self-assembling micelle-like nanoparticle that was based on phospholipid-polyethylenimine conjugates, i.e., "micelle-like nanoparticles" (MNPs). In this study, we aimed to improve the system by enhancing the efficiency of intracellular delivery of the payload via pH-responsive detachment of the monolayer envelope and release of the nucleic acid therapeutics upon reaching the target tissues with an acidic pH, e.g., tumors. The acid-cleavable phospholipid-polyethylenimine conjugate was synthesized via hydrazone bond, and acid-cleavable MNPs were then prepared and characterized as before. We evaluated the acid-cleavable MNP construct for in vitro and in vivo nucleic acid delivery efficiency using cultured tumor cells and tumor-bearing mice. The acid-cleavable nanocarrier showed an enhanced cellular delivery at pH 6.5 as compared to pH 7.4, whereas the noncleavable nanocarrier did not show any differences. Tail vein injections also led to enhanced intracellular uptake of the acid-cleavable nanocarrier compared to the noncleavable nanocarrier into tumor cells of tumor-bearing mice although no significant difference was observed in total tumor accumulation.

  11. Biochar enhances Aspergillus niger rock phosphate solubilization by increasing organic acid production and alleviating fluoride toxicity.

    Science.gov (United States)

    Mendes, Gilberto de Oliveira; Zafra, David Lopez; Vassilev, Nikolay Bojkov; Silva, Ivo Ribeiro; Ribeiro, José Ivo; Costa, Maurício Dutra

    2014-05-01

    During fungal rock phosphate (RP) solubilization, a significant quantity of fluoride (F(-)) is released together with phosphorus (P), strongly inhibiting the process. In the present study, the effect of two F(-) adsorbents [activated alumina (Al2O3) and biochar] on RP solubilization by Aspergillus niger was examined. Al2O3 adsorbed part of the F(-) released but also adsorbed soluble P, which makes it inappropriate for microbial RP solubilization systems. In contrast, biochar adsorbed only F(-) while enhancing phosphate solubilization 3-fold, leading to the accumulation of up to 160 mg of P per liter. By comparing the values of F(-) measured in solution at the end of incubation and those from a predictive model, it was estimated that up to 19 mg of F(-) per liter can be removed from solution by biochar when added at 3 g liter(-1) to the culture medium. Thus, biochar acted as an F(-) sink during RP solubilization and led to an F(-) concentration in solution that was less inhibitory to the process. In the presence of biochar, A. niger produced larger amounts of citric, gluconic, and oxalic acids, whether RP was present or not. Our results show that biochar enhances RP solubilization through two interrelated processes: partial removal of the released F(-) and increased organic acid production. Given the importance of organic acids for P solubilization and that most of the RPs contain high concentrations of F(-), the proposed solubilization system offers an important technological improvement for the microbial production of soluble P fertilizers from RP.

  12. Enhancement of solubility and mass transfer coefficient of salicylic acid through hydrotropy

    Institute of Scientific and Technical Information of China (English)

    S.THENESHKUMAR; D.GNANAPRAKASH; N.NAGENDRA GANDHI

    2009-01-01

    This study deals with the effect of hydrotropes on the solubility and mass transfer coefficient of salicylic acid.The solubility and mass transfer studies were performed using the hydrotropes,i.e.,sodium acetate,sodium salicylate,citric acid,and urea at concentrations of 0~3.0 mol/L and system temperatures of 303-333 K.It was found that the solubility and mass transfer coefficient of salicylic acid increases with increase in hydrotrope concentration and also with system temperature.All hydrotropes used in this work showed an enhancement in solubility and mass transfer coefficient to difierent degrees.The maximum enhancement factor values were determined for all hydrotropes used in this study.The highest value was 28.08 for solubility studies and 10.42 for mass trailsfer studies.The performance of hydrotropes Was measured in terms of the Setschenow constant(Ks).The highest value observed was 0.696.

  13. Okadaic acid and trifluoperazine enhance Agrobacterium-mediated transformation in eastern white pine.

    Science.gov (United States)

    Tang, Wei; Lin, Jinxing; Newton, Ronald J

    2007-05-01

    Mature zygotic embryos of recalcitrant Christmas tree species eastern white pine (Pinus strobus L.) were used as explants for Agrobacterium tumefaciens strain GV3101-mediated transformation using the uidA (beta-Glucuronidase) gene as a reporter. Influence of the time of sonication and the concentrations of protein phosphatase inhibitor (okadaic acid) and kinase inhibitor (trifluoperazine) on Agrobacterium-mediated transformation have been evaluated. A high transformation frequency was obtained after embryos were sonicated for 45-50 s, or treated with 1.5-2.0 microM okadaic acid or treated with 100-200 microM trifluoperazine, respectively. Protein phosphatase and kinase inhibitors enhance Agrobacterium-mediated transformation in eastern white pine. A 2-3.5-fold higher rate of hygromycin-resistant callus was obtained with an addition of 2 microM okadaic acid or 150 microM trifluoperazine or sonicated embryos for 45 s. Stable integration of the uidA gene in the plant genome of eastern white pine was confirmed by polymerase chain reaction (PCR), Southern and northern blot analyses. These results demonstrated that a stable and enhanced transformation system has been established in eastern white pine and this system would provide an opportunity to transfer economically important genes into this Christmas tree species.

  14. Synergistic permeability enhancing effect of lysophospholipids and fatty acids on lipid membranes

    DEFF Research Database (Denmark)

    Davidsen, Jesper; Mouritsen, O.G.; Jørgensen, K.

    2002-01-01

    The permeability-enhancing effects of the two surfactants, 1-paltnitoyl-2-lyso-sn-gycero-3-pllosplloclloline (lysoPPC) and palmitic acid (PA), on lipid membranes that at physiological temperatures are in the gel, fluid, and liquid-ordered phases were determined using the concentration-dependent s......The permeability-enhancing effects of the two surfactants, 1-paltnitoyl-2-lyso-sn-gycero-3-pllosplloclloline (lysoPPC) and palmitic acid (PA), on lipid membranes that at physiological temperatures are in the gel, fluid, and liquid-ordered phases were determined using the concentration......-dependent self-quenching properties of the hydrophilic marker, calcein. Adding lysoPPC to lipid membranes in the gel-phase induced a time-dependent calcein release curve that can be described by the sum of two exponentials, whereas RA induces a considerably more complex release curve. However, when lyso......PPC and PA were added simultaneously in equimolar concentrations, a dramatic synergistic permeability-enhancing effect was observed. In contrast, when both lysoPPC and PA are added to liposomal membranes that are in the fluid or liquid-ordered phases, no effect on the transmembrane permeation of calcein...

  15. Abscisic Acid Regulation of Root Hydraulic Conductivity and Aquaporin Gene Expression Is Crucial to the Plant Shoot Growth Enhancement Caused by Rhizosphere Humic Acids.

    Science.gov (United States)

    Olaetxea, Maite; Mora, Verónica; Bacaicoa, Eva; Garnica, María; Fuentes, Marta; Casanova, Esther; Zamarreño, Angel M; Iriarte, Juan C; Etayo, David; Ederra, Iñigo; Gonzalo, Ramón; Baigorri, Roberto; García-Mina, Jose M

    2015-12-01

    The physiological and metabolic mechanisms behind the humic acid-mediated plant growth enhancement are discussed in detail. Experiments using cucumber (Cucumis sativus) plants show that the shoot growth enhancement caused by a structurally well-characterized humic acid with sedimentary origin is functionally associated with significant increases in abscisic acid (ABA) root concentration and root hydraulic conductivity. Complementary experiments involving a blocking agent of cell wall pores and water root transport (polyethylenglycol) show that increases in root hydraulic conductivity are essential in the shoot growth-promoting action of the model humic acid. Further experiments involving an inhibitor of ABA biosynthesis in root and shoot (fluridone) show that the humic acid-mediated enhancement of both root hydraulic conductivity and shoot growth depended on ABA signaling pathways. These experiments also show that a significant increase in the gene expression of the main root plasma membrane aquaporins is associated with the increase of root hydraulic conductivity caused by the model humic acid. Finally, experimental data suggest that all of these actions of model humic acid on root functionality, which are linked to its beneficial action on plant shoot growth, are likely related to the conformational structure of humic acid in solution and its interaction with the cell wall at the root surface.

  16. Enhancement and modeling of microparticle-added Rhizopus oryzae lactic acid production.

    Science.gov (United States)

    Coban, Hasan Bugra; Demirci, Ali

    2016-02-01

    Lactic acid has a wide industrial application area and can be produced by fungal strains. However, excessive bulk growth form of fungi during the fermentations is a major problem, which limits the fermentation performance. Microparticles are excellent tools to prevent bulk fungal growth and provide homogenized fermentation broth to increase uniformity and the prediction performance of the models. Therefore, in this study, addition of aluminum oxide and talcum microparticles into fermentations was evaluated to enhance the production of lactic acid by Rhizopus oryzae. The results showed that the bulk fungal growth was prevented and the lactic acid concentration increased from 6.02 to 13.88 and 24.01 g/L, when 15 g/L of aluminum oxide or 10 g/L of talcum was used, respectively, in the shake-flask fermentations. Additionally, substrate concentration, pH, and agitation were optimized in the bioreactors using response surface methodology, and optimum values were determined as 126 g/L of glucose, 6.22 pH, and 387 rpm, respectively. Under these conditions, lactic acid production further increased to 75.1 ± 1.5 g/L with 10 g/L of talcum addition. Also, lactic acid production and glucose consumption in the batch fermentation were successfully modeled with modified Gompertz model and modified logistic model. RMSE and MAE values for lactic acid production were calculated as 2.279 and 1.498 for the modified Gompertz model; 3.6 and 4.056 for the modified logistic model. Additionally, modified logistic model predicted glucose consumption with -2.088 MAE and 2.868 RMSE, whereas these values were calculated as 2.035 and 3.946 for the modified Gompertz model.

  17. Organic acids enhance bioavailability of tetracycline in water to Escherichia coli for uptake and expression of antibiotic resistance.

    Science.gov (United States)

    Zhang, Yingjie; Boyd, Stephen A; Teppen, Brian J; Tiedje, James M; Li, Hui

    2014-11-15

    Tetracyclines are a large class of antimicrobials used most extensively in livestock feeding operations. A large portion of tetracyclines administered to livestock is excreted in manure and urine which is collected in waste lagoons. Subsequent land application of these wastes introduces tetracyclines into the soil environment, where they could exert selective pressure for the development of antibiotic resistance genes in bacteria. Tetracyclines form metal-complexes in natural waters, which could reduce their bioavailability for bacterial uptake. We hypothesized that many naturally-occurring organic acids could effectively compete with tetracyclines as ligands for metal cations, hence altering the bioavailability of tetracyclines to bacteria in a manner that could enhance the selective pressure. In this study, we investigated the influence of acetic acid, succinic acid, malonic acid, oxalic acid and citric acid on tetracycline uptake from water by Escherichia coli bioreporter construct containing a tetracycline resistance gene which induces the emission of green fluorescence when activated. The presence of the added organic acid ligands altered tetracycline speciation in a manner that enhanced tetracycline uptake by E. coli. Increased bacterial uptake of tetracycline and concomitant enhanced antibiotic resistance response were quantified, and shown to be positively related to the degree of organic acid ligand complexation of metal cations in the order of citric acid > oxalic acid > malonic acid > succinic acid > acetic acid. The magnitude of the bioresponse increased with increasing aqueous organic acid concentration. Apparent positive relation between intracellular tetracycline concentration and zwitterionic tetracycline species in aqueous solution indicates that (net) neutral tetracycline is the species which most readily enters E. coli cells. Understanding how naturally-occurring organic acid ligands affect tetracycline speciation in solution, and how speciation

  18. The uptake transporter OATP8 expression decreases during multistep hepatocarcinogenesis: correlation with gadoxetic acid enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kitao, Azusa; Matsui, Osamu; Yoneda, Norihide; Kozaka, Kazuto; Shinmura, Rieko; Koda, Wataru; Kobayashi, Satoshi; Gabata, Toshifumi [Kanazawa University Graduate School of Medical Science, Department of Radiology, Kanazawa (Japan); Zen, Yoh [Kanazawa University Graduate School of Medical Science, Human Pathology, Kanazawa (Japan); King' s College Hospital, Institute of Liver Studies, London (United Kingdom); Yamashita, Tatsuya; Kaneko, Shuichi [Kanazawa University Graduate School of Medical Science, Gastroenterology, Kanazawa (Japan); Nakanuma, Yasuni [Kanazawa University Graduate School of Medical Science, Human Pathology, Kanazawa (Japan)

    2011-10-15

    To clarify the changes in organic anion-transporting polypeptide 8 (OATP8) expression and enhancement ratio on gadoxetic acid-enhanced MR imaging in hepatocellular nodules during multistep hepatocarcinogenesis. In imaging analysis, we focused on 71 surgically resected hepatocellular carcinomas (well, moderately and poorly differentiated HCCs) and 1 dysplastic nodule (DN). We examined the enhancement ratio in the hepatobiliary phase of gadoxetic acid enhanced MR imaging [(1/postcontrast T1 value-1/precontrast T1 value)/(1/precontrast T1 value)], then analysed the correlation among the enhancement ratio, tumour differentiation grade and intensity of immunohistochemical OATP8 expression. In pathological analysis, we focused on surgically resected 190 hepatocellular nodules: low-grade DNs, high-grade DNs, early HCCs, well-differentiated, moderately differentiated and poorly differentiated HCCs, including cases without gadoxetic acid-enhanced MR imaging. We evaluated the correlation between the immunohistochemical OATP8 expression and the tumour differentiation grade. The enhancement ratio of HCCs decreased in accordance with the decline in tumour differentiation (P < 0.0001, R = 0.28) and with the decline of OATP8 expression (P < 0.0001, R = 0.81). The immunohistochemical OATP8 expression decreased from low-grade DNs to poorly differentiated HCCs (P < 0.0001, R = 0.15). The immunohistochemical expression of OATP8 significantly decreases during multistep hepatocarcinogenesis, which may explain the decrease in enhancement ratio on gadoxetic acid-enhanced MR imaging. (orig.)

  19. Gold Nanoparticles Enhance the Anticancer Activity of Gallic Acid against Cholangiocarcinoma Cell Lines.

    Science.gov (United States)

    Rattanata, Narintorn; Daduang, Sakda; Wongwattanakul, Molin; Leelayuwat, Chanvit; Limpaiboon, Temduang; Lekphrom, Ratsami; Sandee, Alisa; Boonsiri, Patcharee; Chio-Srichan, Sirinart; Daduang, Jureerut

    2015-01-01

    Gold nanoparticles (GNPs) were conjugated with gallic acid (GA) at various concentrations between 30 and 150 μM and characterized using transmission electron microscopy (TEM) and UV-Vis spectroscopy (UV-VIS). The anticancer activities of the gallic acid-stabilized gold nanoparticles against well-differentiated (M213) and moderately differentiated (M214) adenocarcinomas were then determined using a neutral red assay. The GA mechanism of action was evaluated using Fourier transform infrared (FTIR) microspectroscopy. Distinctive features of the FTIR spectra between the control and GA-treated cells were confirmed by principal component analysis (PCA). The surface plasmon resonance spectra of the GNPs had a maximum absorption at 520 nm, whereas GNPs-GA shifted the maximum absorption values. In an in vitro study, the complexed GNPs-GA had an increased ability to inhibit the proliferation of cancer cells that was statistically significant (Pacids, which may enhance the efficacy of this anticancer activity regarding apoptosis pathways.

  20. Enhanced biodegradation of anthracene in acidic soil by inoculated Burkholderia sp. VUN10013.

    Science.gov (United States)

    Somtrakoon, Khanitta; Suanjit, Sudarat; Pokethitiyook, Prayad; Kruatrachue, Maleeya; Lee, Hung; Upatham, Suchart

    2008-08-01

    The ability of Burkholderia sp. VUN10013 to degrade anthracene in microcosms of two acidic Thai soils was studied. The addition of Burkholderia sp. VUN10013 (initial concentration of 10(5) cells g(-1) dry soil) to autoclaved soil collected from the Plew District, Chanthaburi Province, Thailand, supplemented with anthracene (50 mg kg(-1) dry soil) resulted in complete degradation of the added anthracene within 20 days. In contrast, under the same test conditions but using autoclaved soil collected from the Kitchagude District, Chanthaburi Province, Thailand, only approximately 46.3% of the added anthracene was degraded after 60 days of incubation. In nonautoclaved soils, without adding the VUN10013 inocula, 22.8 and 19.1% of the anthracene in Plew and Kitchagude soils, respectively, were degraded by indigenous bacteria after 60 days. In nonautoclaved soil inoculated with Burkholderia sp. VUN10013, the rate and extent of anthracene degradation were considerably better than those seen in autoclaved soils or in uninoculated nonautoclaved soils in that only 8.2 and 9.1% of anthracene remained in nonautoclaved Plew and Kitchagude soils, respectively, after 10 days of incubation. The results showed that the indigenous microorganisms in the pristine acidic soils have limited ability to degrade anthracene. Inoculation with the anthracene-degrading Burkholderia sp. VUN10013 significantly enhanced anthracene degradation in such acidic soils. The indigenous microorganisms greatly assisted the VUN10013 inoculum in anthracene degradation, especially in the more acidic Kitchagude soil.

  1. Evaluation of hyper thermal acid hydrolysis of Kappaphycus alvarezii for enhanced bioethanol production.

    Science.gov (United States)

    Ra, Chae Hun; Nguyen, Trung Hau; Jeong, Gwi-Taek; Kim, Sung-Koo

    2016-06-01

    Hyper thermal (HT) acid hydrolysis of Kappaphycus alvarezii, a red seaweed, was optimized to 12% (w/v) seaweed slurry content, 180mM H2SO4 at 140°C for 5min. The maximum monosaccharide concentration of 38.3g/L and 66.7% conversion from total fermentable monosaccharides of 57.6g/L with 120gdw/L K. alvarezii slurry were obtained from HT acid hydrolysis and enzymatic saccharification. HT acid hydrolysis at a severity factor of 0.78 efficiently converted the carbohydrates of seaweed to monosaccharides and produced a low concentration of inhibitory compounds. The levels of ethanol production by separate hydrolysis and fermentation with non-adapted and adapted Kluyveromyces marxianus to high concentration of galactose were 6.1g/L with ethanol yield (YEtOH) of 0.19 at 84h and 16.0g/L with YEtOH of 0.42 at 72h, respectively. Development of the HT acid hydrolysis process and adapted yeast could enhance the overall ethanol fermentation yields of K. alvarezii seaweed.

  2. Peracetic acid-ionic liquid pretreatment to enhance enzymatic saccharification of lignocellulosic biomass.

    Science.gov (United States)

    Uju; Abe, Kojiro; Uemura, Nobuyuki; Oshima, Toyoji; Goto, Masahiro; Kamiya, Noriho

    2013-06-01

    To enhance enzymatic saccharification of pine biomass, the pretreatment reagents peracetic acid (PAA) and ionic liquid (IL) were validated in single reagent pretreatments or combination pretreatments with different sequences. In a 1h saccharification, 5-25% cellulose conversion was obtained from the single pretreatment of PAA or IL. In contrast, a marked enhancement in conversion rates was achieved by PAA-IL combination pretreatments (45-70%). The PAA followed by IL (PAA+IL) pretreatment sequence was the most effective for preparing an enzymatic digestible regenerated biomass with 250-fold higher glucose formation rates than untreated biomass and 2- to 12-fold higher than single pretreatments with PAA or IL alone. Structural analysis confirmed that this pretreatment resulted in biomass with highly porous structural fibers associated with the reduction of lignin content and acetyl groups. Using the PAA+IL sequence, biomass loading in the pretreatment step can be increased from 5% to 15% without significant decrease in cellulose conversion.

  3. Enhanced cellular uptake of protoporphyrine IX/linolenic acid-conjugated spherical nanohybrids for photodynamic therapy.

    Science.gov (United States)

    Lee, Hye-In; Kim, Young-Jin

    2016-06-01

    Protoporphyrin IX (PpIX) has wide applications in photodynamic diagnosis and photodynamic therapy (PDT) in many human diseases. However, poor water solubility and cancer cell localization limit its direct application for PDT. We improved the water-solubility and cellular internalization of PpIX to enhance PDT efficacy by developing biocompatible PpIX/linolenic acid-conjugated polyhedral oligomeric silsesquioxane (PPLA) nanohybrids. The resulting PPLA nanohybrids exhibited a quasi-spherical shape with a size of gastric cancer cells. These results imply that the PPLA nanohybrid system may be applicable in PDT.

  4. Optical clearing of skin enhanced with hyaluronic acid for increased contrast of optoacoustic imaging

    Science.gov (United States)

    Liopo, Anton; Su, Richard; Tsyboulski, Dmitri A.; Oraevsky, Alexander A.

    2016-08-01

    Enhanced delivery of optical clearing agents (OCA) through skin may improve sensitivity of optical and optoacoustic (OA) methods of imaging, sensing, and monitoring. This report describes a two-step method for enhancement of light penetration through skin. Here, we demonstrate that topical application of hyaluronic acid (HA) improves skin penetration of hydrophilic and lipophilic OCA and thus enhances their performance. We examined the OC effect of 100% polyethylene and polypropylene glycols (PPGs) and their mixture after pretreatment by HA, and demonstrated significant increase in efficiency of light penetration through skin. Increased light transmission resulted in a significant increase of OA image contrast in vitro. Topical pretreatment of skin for about 30 min with 0.5% HA in aqueous solution offers effective delivery of low molecular weight OCA such as a mixture of PPG-425 and polyethylene glycol (PEG)-400. The developed approach of pretreatment by HA prior to application of clearing agents (PEG and PPG) resulted in a ˜47-fold increase in transmission of red and near-infrared light and significantly enhanced contrast of OA images.

  5. Comparative proteomic analysis of differentially expressed proteins in β-aminobutyric acid enhanced Arabidopsis thaliana tolerance to simulated acid rain.

    Science.gov (United States)

    Liu, Tingwu; Jiang, Xinwu; Shi, Wuliang; Chen, Juan; Pei, Zhenming; Zheng, Hailei

    2011-05-01

    Acid rain is a worldwide environmental issue that has seriously destroyed forest ecosystems. As a highly effective and broad-spectrum plant resistance-inducing agent, β-aminobutyric acid could elevate the tolerance of Arabidopsis when subjected to simulated acid rain. Using comparative proteomic strategies, we analyzed 203 significantly varied proteins of which 175 proteins were identified responding to β-aminobutyric acid in the absence and presence of simulated acid rain. They could be divided into ten groups according to their biological functions. Among them, the majority was cell rescue, development and defense-related proteins, followed by transcription, protein synthesis, folding, modification and destination-associated proteins. Our conclusion is β-aminobutyric acid can lead to a large-scale primary metabolism change and simultaneously activate antioxidant system and salicylic acid, jasmonic acid, abscisic acid signaling pathways. In addition, β-aminobutyric acid can reinforce physical barriers to defend simulated acid rain stress.

  6. Metabolic engineering of Clostridium acetobutylicum for enhanced production of butyric acid.

    Science.gov (United States)

    Jang, Yu-Sin; Woo, Hee Moon; Im, Jung Ae; Kim, In Ho; Lee, Sang Yup

    2013-11-01

    Clostridium acetobutylicum has been considered as an attractive platform host for biorefinery due to its metabolic diversity. Considering its capability to overproduce butanol through butyrate, it was thought that butyric acid can also be efficiently produced by this bacterium through metabolic engineering. The pta-ctfB-deficient C. acetobutylicum CEKW, in which genes encoding phosphotransacetylase and CoA-transferase were knocked out, was assessed for its potential as a butyric acid producer in fermentations with four controlled pH values at 5.0, 5.5, 6.0, and 6.4. Butyric acid could be best produced by fermentation of the CEKW at pH 6.0, resulting in the highest titer of 26.6 g/l, which is 6.4 times higher than that obtained with the wild type. However, due to the remaining solventogenic ability of the CEKW, 3.6 g/l solvents were also produced. Thus, the CEKW was further engineered by knocking out the adhE1-encoding aldehyde/alcohol dehydrogenase to prevent solvent production. Batch fermentation of the resulting C. acetobutylicum HCEKW at pH 6.0 showed increased butyric acid production to 30.8 g/l with a ratio of butyric-to-acetic acid (BA/AA) of 6.6 g/g and a productivity of 0.72 g/l/h from 86.9 g/l glucose, while negligible solvent (0.8 g/l ethanol only) was produced. The butyric acid titer, BA/AA ratio, and productivity obtained in this study were the highest values reported for C. acetobutylicum, and the BA/AA ratio and productivity were also comparable to those of native butyric acid producer Clostridium tyrobutyricum. These results suggested that the simultaneous deletion of the pta-ctfB-adhE1 in C. acetobutylicum resulted in metabolic switch from biphasic to acidogenic fermentation, which enhanced butyric acid production.

  7. Using Laboratory Activities Enhanced with Concept Cartoons to Support Progression in Students' Understanding of Acid-Base Concepts

    Science.gov (United States)

    Ozmen, Haluk; Demircioglu, Gokhan; Burhan, Yasemin; Naseriazar, Akbar; Demircioglu, Hulya

    2012-01-01

    The aim of this study is to examine the effectiveness of an intervention based on a series of laboratory activities enhanced with concept cartoons. The purpose of the intervention was to enhance students' understanding of acid-base chemistry for eight grade students' from two classes in a Turkish primary school. A pretest-posttest non-equivalent…

  8. Label-free direct surface-enhanced Raman scattering (SERS) of nucleic acids (Conference Presentation)

    Science.gov (United States)

    Guerrini, Luca; Morla-Folch, Judit; Gisbert-Quilis, Patricia; Xie, Hainan; Alvarez-Puebla, Ramon

    2016-03-01

    Recently, plasmonic-based biosensing has experienced an unprecedented level of attention, with a particular focus on the nucleic acid detection, offering efficient solutions to engineer simple, fast, highly sensitive sensing platforms while overcoming important limitations of PCR and microarray techniques. In the broad field of plasmonics, surface-enhanced Raman scattering (SERS) spectroscopy has arisen as a powerful analytical tool for detection and structural characterization of biomolecules. Today applications of SERS to nucleic acid analysis largely rely on indirect strategies, which have been demonstrated very effective for pure sensing purposes but completely dismiss the exquisite structural information provided by the direct acquisition of the biomolecular vibrational fingerprint. Contrarily, direct label-free SERS of nucleic acid shows an outstanding potential in terms of chemical-specific information which, however, remained largely unexpressed mainly because of the inherent poor spectral reproducibility and/or limited sensitivity. To address these limitations, we developed a fast and affordable high-throughput screening direct SERS method for gaining detailed genomic information on nucleic acids (DNA and RNA) and for the characterization and quantitative recognition of DNA interactions with exogenous agents. The simple strategy relies on the electrostatic adhesion of DNA/RNA onto positively-charged silver colloids that promotes the nanoparticle aggregation into stable clusters yielding intense and reproducible SERS spectra at picogram level (i.e. the analysis can be performed without the necessity of amplification steps thus providing realistic direct information of the nucleic acid in its native state). We anticipate this method to gain a vast impact and set of applications in different fields, including medical diagnostics, genomic screening, drug discovery, forensic science and even molecular electronics.

  9. Detection of amino acid neurotransmitters by surface enhanced Raman scattering and hollow core photonic crystal fiber

    Science.gov (United States)

    Tiwari, Vidhu S.; Khetani, Altaf; Monfared, Ali Momenpour T.; Smith, Brett; Anis, Hanan; Trudeau, Vance L.

    2012-03-01

    The present work explores the feasibility of using surface enhanced Raman scattering (SERS) for detecting the neurotransmitters such as glutamate (GLU) and gamma-amino butyric acid (GABA). These amino acid neurotransmitters that respectively mediate fast excitatory and inhibitory neurotransmission in the brain, are important for neuroendocrine control, and upsets in their synthesis are also linked to epilepsy. Our SERS-based detection scheme enabled the detection of low amounts of GLU (10-7 M) and GABA (10-4 M). It may complement existing techniques for characterizing such kinds of neurotransmitters that include high-performance liquid chromatography (HPLC) or mass spectrography (MS). This is mainly because SERS has other advantages such as ease of sample preparation, molecular specificity and sensitivity, thus making it potentially applicable to characterization of experimental brain extracts or clinical diagnostic samples of cerebrospinal fluid and saliva. Using hollow core photonic crystal fiber (HC-PCF) further enhanced the Raman signal relative to that in a standard cuvette providing sensitive detection of GLU and GABA in micro-litre volume of aqueous solutions.

  10. Enhanced esterification of oleic acid and methanol by deep eutectic solvent assisted Amberlyst heterogeneous catalyst.

    Science.gov (United States)

    Pan, Ying; Alam, Md Asraful; Wang, Zhongming; Wu, Jingcheng; Zhang, Yi; Yuan, Zhenhong

    2016-11-01

    In present study, esterification of oleic acid with methanol using deep eutectic solvent (DES) assisted Amberlyst heterogeneous catalyst was investigated to produce biodiesel. Results showed that esterification efficiency was enhanced by the DES. The combined effect of DES on Amberlyst BD20 (BD20) is better than Amberlyst 15 (A-15) due to different structure. The optimal reaction conditions were 12:1M ratio of methanol to oleic acid, 20%(wt/wt) catalyst (BD20-DES (2:8) and A-15-DES (8:2)) at 85°C for 100min with agitating at 200rpm. The mechanism involved in catalysis and their capacity to reuse were studied. We proposed, Choline chloride-glycerol (Chcl-gly) DES could enhance the Amberlyst function due to the hydrogen bond effect on both DES and water. BD20 has fewer pores than A-15, have desirable performance in decreasing the inhibition the water during esterification of high FFA content and provide better performance in reuse.

  11. Docosahexaenoic acid dietary supplementation enhances the effects of exercise on synaptic plasticity and cognition.

    Science.gov (United States)

    Wu, A; Ying, Z; Gomez-Pinilla, F

    2008-08-26

    Omega-3 fatty acids (i.e. docosahexaenoic acid; DHA), similar to exercise, improve cognitive function, promote neuroplasticity, and protect against neurological lesion. In this study, we investigated a possible synergistic action between DHA dietary supplementation and voluntary exercise on modulating synaptic plasticity and cognition. Rats received DHA dietary supplementation (1.25% DHA) with or without voluntary exercise for 12 days. We found that the DHA-enriched diet significantly increased spatial learning ability, and these effects were enhanced by exercise. The DHA-enriched diet increased levels of pro-brain-derived neurotrophic factor (BDNF) and mature BDNF, whereas the additional application of exercise boosted the levels of both. Furthermore, the levels of the activated forms of CREB and synapsin I were incremented by the DHA-enriched diet with greater elevation by the concurrent application of exercise. While the DHA diet reduced hippocampal oxidized protein levels, a combination of a DHA diet and exercise resulted in a greater reduction rate. The levels of activated forms of hippocampal Akt and CaMKII were increased by the DHA-enriched diet, and with even greater elevation by a combination of diet and exercise. Akt and CaMKII signaling are crucial step by which BDNF exerts its action on synaptic plasticity and learning and memory. These results indicate that the DHA diet enhanced the effects of exercise on cognition and BDNF-related synaptic plasticity, a capacity that may be used to promote mental health and reduce risk of neurological disorders.

  12. Transcriptome analysis of acetic-acid-treated yeast cells identifies a large set of genes whose overexpression or deletion enhances acetic acid tolerance.

    Science.gov (United States)

    Lee, Yeji; Nasution, Olviyani; Choi, Eunyong; Choi, In-Geol; Kim, Wankee; Choi, Wonja

    2015-08-01

    Acetic acid inhibits the metabolic activities of Saccharomyces cerevisiae. Therefore, a better understanding of how S. cerevisiae cells acquire the tolerance to acetic acid is of importance to develop robust yeast strains to be used in industry. To do this, we examined the transcriptional changes that occur at 12 h post-exposure to acetic acid, revealing that 56 and 58 genes were upregulated and downregulated, respectively. Functional categorization of them revealed that 22 protein synthesis genes and 14 stress response genes constituted the largest portion of the upregulated and downregulated genes, respectively. To evaluate the association of the regulated genes with acetic acid tolerance, 3 upregulated genes (DBP2, ASC1, and GND1) were selected among 34 non-protein synthesis genes, and 54 viable mutants individually deleted for the downregulated genes were retrieved from the non-essential haploid deletion library. Strains overexpressing ASC1 and GND1 displayed enhanced tolerance to acetic acid, whereas a strain overexpressing DBP2 was sensitive. Fifty of 54 deletion mutants displayed enhanced acetic acid tolerance. Three chosen deletion mutants (hsps82Δ, ato2Δ, and ssa3Δ) were also tolerant to benzoic acid but not propionic and sorbic acids. Moreover, all those five (two overexpressing and three deleted) strains were more efficient in proton efflux and lower in membrane permeability and internal hydrogen peroxide content than controls. Individually or in combination, those physiological changes are likely to contribute at least in part to enhanced acetic acid tolerance. Overall, information of our transcriptional profile was very useful to identify molecular factors associated with acetic acid tolerance.

  13. Gadoxetate Acid-Enhanced MR Imaging for HCC: A Review for Clinicians

    Directory of Open Access Journals (Sweden)

    Jendana Chanyaputhipong

    2011-01-01

    Full Text Available Hepatocellular carcinoma (HCC is increasingly being detected at an earlier stage, owing to the screening programs and regular imaging follow-up in high-risk populations. Small HCCs still pose diagnostic challenges on imaging due to decreased sensitivity and increased frequency of atypical features. Differentiating early HCC from premalignant or benign nodules is important as management differs and has implications on both the quality of life and the overall survival for the patients. Gadoxetate acid (Gd-EOB-DTPA, Primovist®, Bayer Schering Pharma is a relatively new, safe and well-tolerated liver-specific contrast agent for magnetic resonance (MR imaging of the liver that has combined perfusion- and hepatocyte-specific properties, allowing for the acquisition of both dynamic and hepatobiliary phase images. Its high biliary uptake and excretion improves lesion detection and characterization by increasing liver-to-lesion conspicuity in the added hepatobiliary phase imaging. To date, gadoxetate acid-enhanced MRI has been mostly shown to be superior to unenhanced MRI, computed tomography, and other types of contrast agents in the detection and characterization of liver lesions. This review article focuses on the evolving role of gadoxetate acid in the characterization of HCC, differentiating it from other mimickers of HCC.

  14. Enhanced Blood Compatibility of Metallocene Polyethylene Subjected to Hydrochloric Acid Treatment for Cardiovascular Implants

    Directory of Open Access Journals (Sweden)

    Saravana Kumar Jaganathan

    2014-01-01

    Full Text Available Blood compatibility of metallocene polyethylene (mPE was investigated after modifying the surface using hydrochloric acid. Contact angle of the mPE exposed to HCl poses a decrease in its value which indicates increasing wettability and better blood compatibility. Surface of mPE analyzed by using FTIR revealed no significant changes in its functional groups after treatment. Furthermore, scanning electron microscope images supported the increasing wettability through the modifications like pit formations and etching on the acid rendered surface. To evaluate the effect of acid treatment on the coagulation cascade, prothrombin time (PT and activated partial thromboplastin time (APTT were measured. Both PT and APTT were delayed significantly (P<0.05 after 60 min exposure implying improved blood compatibility of the surfaces. Hemolysis assay of the treated surface showed a remarkable decrease in the percentage of lysis of red blood cells when compared with untreated surface. Moreover, platelet adhesion assay demonstrated that HCl exposed surfaces deter the attachment of platelets and thereby reduce the chances of activation of blood coagulation cascade. These results confirmed the enhanced blood compatibility of mPE after HCl exposure which can be utilized for cardiovascular implants like artificial vascular prostheses, implants, and various blood contacting devices.

  15. Acid-etched microtexture for enhancement of bone growth into porous-coated implants.

    Science.gov (United States)

    Hacking, S A; Harvey, E J; Tanzer, M; Krygier, J J; Bobyn, J D

    2003-11-01

    We designed an in vivo study to determine if the superimposition of a microtexture on the surface of sintered titanium beads affected the extent of bone ingrowth. Cylindrical titanium intramedullary implants were coated with titanium beads to form a porous finish using commercial sintering techniques. A control group of implants was left in the as-sintered condition. The test group was etched in a boiling acidic solution to create an irregular surface over the entire porous coating. Six experimental dogs underwent simultaneous bilateral femoral intramedullary implantation of a control implant and an acid etched implant. At 12 weeks, the implants were harvested in situ and the femora processed for undecalcified, histological examination. Eight transverse serial sections for each implant were analysed by backscattered electron microscopy and the extent of bone ingrowth was quantified by computer-aided image analysis. The extent of bone ingrowth into the control implants was 15.8% while the extent of bone ingrowth into the etched implants was 25.3%, a difference of 60% that was statistically significant. These results are consistent with other research that documents the positive effect of microtextured surfaces on bone formation at an implant surface. The acid etching process developed for this study represents a simple method for enhancing the potential of commonly available porous coatings for biological fixation.

  16. Freezing-Enhanced Dissolution of Iron Oxides: Effects of Inorganic Acid Anions.

    Science.gov (United States)

    Jeong, Daun; Kim, Kitae; Min, Dae Wi; Choi, Wonyong

    2015-11-03

    Dissolution of iron from mineral dust particles greatly depends upon the type and amount of copresent inorganic anions. In this study, we investigated the roles of sulfate, chloride, nitrate, and perchlorate on the dissolution of maghemite and lepidocrocite in ice under both dark and UV irradiation and compared the results with those of their aqueous counterparts. After 96 h of reaction, the total dissolved iron in ice (pH 3 before freezing) was higher than that in the aqueous phase (pH 3) by 6-28 times and 10-20 times under dark and UV irradiation, respectively. Sulfuric acid was the most efficient in producing labile iron under dark condition, whereas hydrochloric acid induced the most dissolution of the total and ferrous iron in the presence of light. This ice-induced dissolution result was also confirmed with Arizona Test Dust (AZTD). In the freeze-thaw cycling test, the iron oxide samples containing chloride, nitrate, or perchlorate showed a similar extent of total dissolved iron after each cycling while the sulfate-containing sample rapidly lost its dissolution activity with repeating the cycle. This unique phenomenon observed in ice might be related to the freeze concentration of protons, iron oxides, and inorganic anions in the liquid-like ice grain boundary region. These results suggest that the ice-enhanced dissolution of iron oxides can be a potential source of bioavailable iron, and the acid anions critically influence this process.

  17. Facile plasma-enhanced deposition of ultrathin crosslinked amino acid films for conformal biometallization.

    Science.gov (United States)

    Anderson, Kyle D; Slocik, Joseph M; McConney, Michael E; Enlow, Jesse O; Jakubiak, Rachel; Bunning, Timothy J; Naik, Rajesh R; Tsukruk, Vladimir V

    2009-03-01

    A novel method for the facile fabrication of conformal, ultrathin, and uniform synthetic amino acid coatings on a variety of practical surfaces by plasma-enhanced chemical vapor deposition is introduced. Tyrosine, which is utilized as an agent to reduce gold nanoparticles from solution, is sublimed into the plasma field and directly deposited on a variety of substrates to form a homogeneous, conformal, and robust polyamino acid coating in a one-step, solvent-free process. This approach is applicable to many practical surfaces and allows surface-induced biometallization while avoiding multiple wet-chemistry treatments that can damage many soft materials. Moreover, by placing a mask over the substrate during deposition, the tyrosine coating can be micropatterned. Upon its exposure to a solution of gold chloride, a network of gold nanoparticles forms on the surface, replicating the initial micropattern. This method of templated biometallization is adaptable to a variety of practical inorganic and organic substrates, such as silicon, glass, nitrocellulose, polystyrene, polydimethylsiloxane, polytetrafluoroethylene, polyethylene, and woven silk fibers. No special pretreatment is necessary, and the technique results in a rapid, conformal amino acid coating that can be utilized for further biometallization.

  18. Aliphatic carboxylic acids and alcohols as efficiency and elution strength enhancers in micellar liquid chromatography.

    Science.gov (United States)

    Boichenko, Alexander P; Berthod, Alain

    2010-09-03

    Micellar liquid chromatography (MLC) uses surfactant solutions as mobile phases with added organic additives to enhance both the elution strength and the chromatographic efficiency. Two aliphatic carboxylic acids (1-butanoic and 1-pentanoic) were used as MLC additives and compared with the two corresponding alcohols (1-butanol, 1-pentanol) in terms of elution strength, efficiency and selectivity. A set of 11 phenol derivatives was used as probe compounds. All micellar mobile phases were prepared with sodium dodecylsulfate (SDS) with concentration ranging from 0.05 to 0.15M and the modifier content within 1.0 and 5.0% (v/v). The elution strength of different mobile phases containing a constant amount of SDS and different amounts of modifiers; and mobile phases containing a constant amount of modifier and different SDS concentration were determined and discussed. The effect of the acid modifiers on efficiency was studied constructing van Deemter plots that showed no minimum within the 0.01-0.7mL/min flow rate range studied. Temperature effects were also studied constructing the classical van't Hoff plots. The slight curvature of the plots in the 25-70 degrees C range may indicate some modification of the surfactant-bonded moiety layer on the stationary phase surface. Since no definitive advantage of the use of aliphatic acids were established compared to their alcohol counterpart, their terrible smell will probably preclude their use as MLC organic modifiers.

  19. Acid and alkaline treatments for enhancing the growth of rhizobia in sludge

    Energy Technology Data Exchange (ETDEWEB)

    Rebah, F. B.; Tyagi, R. D. [Quebec Univ., Institut national de la recherche scientifique, Sainte Foy, PQ (Canada); Prevost, D. [Agriculture and Agri-Food Canada, Centre de recherche et de developpement sur les sols et les grandes cultures, Sainte Foy, PQ (Canada)

    2001-06-01

    Wastewater treatment processes produce large amounts of sludge. The application of sludge to agricultural soils improves the soil's physical and biological properties because it contains organic matter and plant nutrients. Wastewater sludge has been used for producing certain bacteria. It has also been proposed as an effective method for the production of rhizobia. Although the amount of sludge required for the production of bacterial inoculum is low, this new application constitutes an additional and suitable alternative for wastewater sludge recycling. The purpose of this study was to determine the potential of using acid or alkaline pre-treatments in sludges having different solid concentrations, to increase the biodegradability of organic material, thereby to enhance the growth of rhizobia, while using sludge as a culture medium. Results of the experiment show that both acid and alkaline treatments improved the rhizobial cell count and reduced mean generation time in primary and secondary sludges, but the efficiency of the treatment was also dependent on the total suspended solids (TSS) concentration. The highest cell count was obtained with primary sludge at 0.65 per cent TSS under alkaline treatment. For secondary sludge, the highest cell count was reached under acid hydrolysis. The mean generation time was reduced by both pre-treatments, with best values obtained for alkaline treatment in primary sludge. 31 refs., 6 tabs.

  20. [Enhanced phytoextraction of heavy metal contaminated soil by chelating agents and auxin indole-3-acetic acid].

    Science.gov (United States)

    Zhou, Jian-min; Dang, Zhi; Chen, Neng-chang; Xu, Sheng-guang; Xie, Zhi-yi

    2007-09-01

    The environmental risk of chelating agents such as EDTA application to the heavy metals polluted soils and the stress on plant roots due to the abrupt increase metals concentration limit the wide commercial use of chelate-induced phytoextraction. Chelating agent ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) and auxin indole-3-acetic acid (IAA) were used for enhancing heavy metals uptake from soils by Zea mays L. (corn) in pot experiments. The metals content in plant tissues was quantified using an inductively coupled plasma mass spectrometer (ICP-MS). The results showed that the combination of IAA and EDTA increased the biomass by about 40.0% and the contents of Cu, Zn, Cd and Pb in corn shoots by 27.0%, 26.8%, 27.5% and 32.8% respectively, as compared to those in EDTA treatment. While NTA&IAA treatment increased the biomass by about 29.9% and the contents of Cu, Zn, Cd and Pb in corn shoots by 31.8%, 27.6%, 17.0% and 26.9% respectively, as compared to those in NTA treatment. These results indicated that corn growth was promoted, and the biomass and the accumulation of heavy metals in plant shoots were increased significantly with the addition of IAA, which probably helps to change the cell membrane properties and the biomass distribution, resulting in the alleviation of the phytotoxicity of metals and the chelating agents.

  1. Studying Pellet Formation of a Filamentous Fungus Rhizopus oryzae to Enhance Organic Acid Production

    Science.gov (United States)

    Liao, Wei; Liu, Yan; Chen, Shulin

    Using pelletized fungal biomass can effectively improve the fermentation performance for most of fugal strains. This article studied the effects of inoculum and medium compositions such as potato dextrose broth (PDB) as carbon source, soybean peptone, calcium carbonate, and metal ions on pellet formation of Rhizopus oryzae. It has been found that metal ions had significantly negative effects on pellet formation whereas soybean peptone had positive effects. In addition PDB and calcium carbonate were beneficial to R. oryzae for growing small smooth pellets during the culture. The study also demonstrated that an inoculum size of less than 1.5×109 spores/L had no significant influence on pellet formation. Thus, a new approach to form pellets has been developed using only PDB, soybean peptone, and calcium carbonate. Meanwhile, palletized fungal fermentation significantly enhanced organic acid production. Lactic acid concentration reached 65.0 g/L in 30 h using pelletized R. oryzae NRRL 395, and fumeric acid concentration reached 31.0 g/L in 96 h using pelletized R. oryzae ATCC 20344.

  2. Flow-injection chemiluminescence determination of acetylsalicylic acid based on its enhancing effect on the lucigenin–hydrogen peroxide system.

    Science.gov (United States)

    Wabaidur, S M; Alam, S M; Alothmana, Z A; Eldesokya, Gaber

    2014-09-01

    A sensitive flow-injection chemiluminescence method for the determination of acetylsalicylic acid is described. It is based on the enhanced chemiluminescent emission of the alkaline lucigenin–H2O2 system by acetylsalicylic acid. The difference in chemiluminescent intensity of alkaline lucigenin–H2O2 in the presence of acetylsalicylic acid from that in the absence of acetylsalicylic acid was linear at acetylsalicylic acid concentrations in the range of 0.0029–47.37 μg/mL, with detection and quantification limits of 0.0011 and 0.0029 μg/mL, respectively. The correlation coefficient of the working curve was 0.9983. The relative standard deviation (n = 10) for 25 μg/mL acetylsalicylic acid is 1.95%. All experimental parameters were optimized. The method was successfully applied to the determination of acetylsalicylic acid in pharmaceutical preparations. The recovery results obtained by the method were satisfactory.

  3. Chromate enhanced visible light driven TiO₂ photocatalytic mechanism on Acid Orange 7 photodegradation.

    Science.gov (United States)

    Wang, Yeoung-Sheng; Shen, Jyun-Hong; Horng, Jao-Jia

    2014-06-15

    When hexavalent chromium (Cr(VI)) is added to a TiO2 photocatalytic reaction, the decolorization and mineralization efficiencies of azo dyes Acid Orange 7 (AO7) are enhanced even though the mechanism is unclear. This study used 5,5-dimethyl-l-pyrroline-N-oxide (DMPO) as the scavenger and the analysis of Electron Spin Resonance (ESR) to investigate this enhancement effect by observing the hydroxyl radical (OH) generation of the Cr(VI)/TiO2 system under UV and visible light (Vis) irradiation. With Cr(VI), the decolorization efficiencies were approximately 95% and 62% under UV and Vis, and those efficiencies were 25% less in the absence of Cr(VI). The phenomena of the DMPO-OH signals during the ESR analysis under Vis 405 and 550 nm irradiation were obviously the enhancement effects of Cr(VI) in aerobic conditions. In anoxic conditions, the catalytic effects of Cr(VI) could not be achieved due to the lack of a redox reaction between Cr(VI) and the adsorbed oxygen at the oxygen vacancy sites on the TiO2 surfaces. The results suggest that by introducing the agents of redox reactions such as chromate ions, we could lower the photoenergy of TiO2 needed and allow Vis irradiation to activate photocatalysis.

  4. Production of Polyamines Is Enhanced by Endogenous Abscisic Acid in Maize Seedlings Subjected to Salt Stress

    Institute of Scientific and Technical Information of China (English)

    Jun LIU; Ming-Yi JIANG; Yi-Feng ZHOU; You-Liang LIU

    2005-01-01

    It is known that salt stress and exogenously applied abscisic acid (ABA) can enhance the polyamine content in plants and that salt stress itself can lead to an increase in endogenous ABA production.In the present study, the relationships between salt-induced ABA and polyamine accumulation were investigated using ABA-deficient mutant (vp5/vp5) maize (Zea mays L.) seedlings and ABA and polyamine :biosynthesis inhibitors. The results show that reduced endogenous ABA levels, as a result of either the mutation or by using a chemical inhibitor (sodium tungstate), also reduced the accumulation of polyamines in salt-stressed leaves of maize seedlings. The polyamine synthesis inhibitors D-arginine and αdifluoromethylornithine also reduced the polyamine content of the leaves of maize seedling under salt stress. Both ABA and polyamine enhanced the dry weight accumulation of salt-stressed seedlings and also increased the activities of the two dominant tonoplast membrane enzymes, H+-ATPase and H+-PPase, when plants were under salt stress. The results suggest that salt stress induces an increase in endogenous ABA levels, which then enhances polyamine synthesis. Such responses may increase a plant's tolerance to salt.

  5. Enhancement of carvedilol solubility by solid dispersion technique using cyclodextrins, water soluble polymers and hydroxyl acid.

    Science.gov (United States)

    Yuvaraja, K; Khanam, Jasmina

    2014-08-01

    Aim of the present work is to enhance aqueous solubility of carvedilol (CV) by solid dispersion technique using wide variety of carriers such as: β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD), tartaric acid (TA), polyvinyl pyrrolidone K-30 (PVP K-30) and poloxamer-407 (PLX-407). Various products of 'CV-solid dispersion' had been studied extensively in various pH conditions to check enhancement of solubility and dissolution characteristics of carvedilol. Any physical change upon interaction between CV and carriers was confirmed by instrumental analysis: XRD, DSC, FTIR and SEM. Negative change of Gibb's free energy and complexation constants (Kc, 75-240M(-1), for cyclodextrins and 1111-20,365M(-1), for PVP K-30 and PLX-407) were the evidence of stable nature of the binding between CV and carriers. 'Solubility enhancement factor' of ionized-CV was found high enough (340 times) with HPβCD in presence of TA. TA increases the binding efficiency of cyclodextrin and changing the pH of microenvironment in dissolution medium. In addition, ionization process was used to increase the apparent intrinsic solubility of drug. In vitro, dissolution time of CV was remarkably reduced in the solid dispersion system compared to that of pure drug. This may be attributed to increased wettability, dispersing ability and transformation of crystalline state of drug to amorphous one.

  6. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis.

    Science.gov (United States)

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-04-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 (-) were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis.

  7. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis

    Science.gov (United States)

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-01-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 − were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis. PMID:27162276

  8. Enhancing post anaerobic digestion of full-scale anaerobically digested sludge using free nitrous acid treatment.

    Science.gov (United States)

    Zhang, Tingting; Wang, Qilin; Ye, Liu; Yuan, Zhiguo

    2016-05-01

    In some wastewater treatment plants (WWTPs), the ever increasing production of sludge with the expanding population overloaded the anaerobic digestion which compromises the sludge reduction efficiency. Post anaerobic digestion of anaerobically digested sludge (ADS) has been applied to enhance sludge reduction, however, to a very limited extent. This study verified the effectiveness of free nitrous acid (FNA i.e. HNO2) pre-treatment on enhancing full-scale ADS degradation in post anaerobic digestion. The ADS collected from a full-scale WWTP was subject to FNA treatment at concentrations of 0.77, 1.54, 2.31, 3.08, and 3.85 mg N/L for 24 h followed by biochemical methane potential tests. The FNA treatment at all concentrations resulted in an increase (from 1.5-3.1 % compared to the control) in sludge reduction with the highest improvement achieved at 0.77 mg HNO2-N/L. The FNA treatment at this concentration also resulted in the highest increase in methane production (40 %) compared to the control. The economic analysis indicates that FNA treatment is economically attractive for enhancing post anaerobic digestion of full-scale ADS.

  9. Improved focal liver lesion detection by increasing flip angle during gadoxetic acid-enhancement in MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Se Jy [Dept. of Medical science Graduate school, Chonnam National University, Kwangju (Korea, Republic of); Kim, Young Keun [Dept. of Radiotechnology, Gwang-ju Health university, Gwangju (Korea, Republic of)

    2015-06-15

    To study the differences of focal liver lesion image detection at 3 minute, 10 minute and 15 minute time points on gadoxetic acid (GA)’s enhanced MR imaging with a flip angle (FA) of 30° compared with a 11°. The subjects were 69 patients evaluated with GA enhanced MR imaging with 3.0T MR scanner. The patients are total 35(23 men and 7 women at the mean age of 60.4 years), hepatocellular carcinoma(23) and metastsis(12) except for normal, cyst and hemangioma. After GA was injected, FA 11° and 30° images were obtained at 3 minute, 10 minute and 15 minute time points respectively. After quantitative and qualitative assessment of each image was done, statistical analysis was performed by using the independent sample T-test. From both quantitative and qualitative assessment of 3 minute and 10 minute MR images after the injection of GA, FA 30° images was found to be superior than FA 11°, but there were no statistical significance. However, at 15 minute time point, Statistically significant FA 30° image(p<0.05) was better than FA 11° therefore, the FA 30° improves the focal liver lesion detection. FA 30° of MR image can detect liver lesion more sensitively than the existing FA11° image after GA contrast enhancement at 15 minute time point.

  10. Screening the possibility for removing cadmium and other heavy metals from wastewater sludge and bio-ashes by an electrodialytic method

    Energy Technology Data Exchange (ETDEWEB)

    Ottosen, Lisbeth M. [Department of Civil Engineering, Techncial University of Denmark, Building 204, 2800 Lyngby (Denmark)]. E-mail: lo@byg.dtu.dk; Pedersen, Anne J. [Department of Civil Engineering, Techncial University of Denmark, Building 204, 2800 Lyngby (Denmark); Hansen, Henrik K. [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Ribeiro, Alexandra B. [Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Cadencies e Technologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2007-02-25

    Both wastewater sludge and fly ash from combustion of biomass (bio-ash) have traditionally been applied to agricultural land in Denmark. However, Cd concentrations often exceed limiting values. The present study is a preliminary investigation of the possibility for reducing the Cd concentration in wastewater sludge and bio-ashes (straw and wood) using an electrodialytic method. The waste products were treated as stirred suspensions. During the remediation the suspension was acidified from water splitting at the anion exchange membrane and the acidification mobilized Cd that was removed to the electrode compartments. Even though the matrices were very different the remediation was successful in all cases. After treatment the Cd concentration in the ashes allowed for spreading at agricultural land and the limiting concentration of 0.8 mg Cd/kg for the wastewater sludge was almost reached (0.84 and 0.88 mg Cd/kg). The main differences of the waste products influencing the remediation process were: the sludges had a high content of organic particles that were mobilized by electrophoresis and fouled the anion exchange membrane; the straw-ash contained a lot of chloride, which formed anionic complexes with Cd, and the wood ash had a high initial pH (13.3). The mass of wastewater sludge and bio-ashes decreased during treatment but the concentration of other heavy metals (Pb, Ni, Cu and Zn) was not increased to exceed limiting values in remediated matrix.

  11. Electrodialytic remediation of sediments

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland

    , in many cases, prohibit this due to contamination by primarily heavy metals and TBT. Similarly, sediments of fresh waters could potentially be used as soil amendment material for poor agricultural soils utilizing their often high content of phosphate and nitrogen. However, again, heavy metal contamination...

  12. Electrodialytic Soil Remediation

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Lene; Hansen, Henrik K.

    1997-01-01

    It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective......It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective...

  13. Electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Karlsmose, Bodil; Ottosen, Lisbeth M.; Hansen, Lene

    1999-01-01

    prevents the protons and the hydroxides ions from the electrode processes to enter the soil. The heavy metals are collected in a concentration compartment, which is separated from the soil by ion-exchange membranes. Examples from remediation experiments are shown, and it is demonstrated that it is possible...

  14. Ion pair formation as a possible mechanism for the enhancement effect of lauric acid on the transdermal permeation of ondansetron.

    Science.gov (United States)

    Dimas, Dimitrios A; Dallas, Paraskevas P; Rekkas, Dimitrios M

    2004-08-01

    Transdermal application can be an alternative drug delivery route for ondansetron, an antiemetic drug. Previous studies found that fatty acids, namely oleic and lauric, were the most effective penetration enhancers. The aim of this study was to investigate the formation of an ion pair between ondansetron and lauric acid as a possible mechanism of its enhancing action. Several techniques were used to reveal the formation of an ion pair complex. Partitioning experiments, where the n-octanol/water coefficient was measured, showed an increase in the distribution coefficient in the presence of the acid, possibly as a result of the formation of more lipophilic ion pairs between the charged molecules of ondansetron and lauric acid. Further evidence of complex formation between ondansetron and lauric acid, was gained from the 13C-nuclear magnetic resonance (13C-NMR) spectra of ondansetron, lauric acid, and their mixture (molar ratio 1:1). The NMR spectra revealed alterations to the magnetic environment of the carbon atoms adjacent to the ionized group, which are the carbonyl group of the acid and the nitrogen of the imidazole ring of ondansetron. This evidence substantiates the theory of ion pair formation. Finally, thermal analysis of the binary mixtures of ondansetron and lauric acid revealed the formation of an additional compound, with different melting point from pure ondansetron and lauric acid, which is thermodynamically favored.

  15. Endoplasmic reticulum-located PDAT1-2 from castor bean enhances hydroxy fatty acid accumulation in transgenic plants.

    Science.gov (United States)

    Kim, Hyun Uk; Lee, Kyeong-Ryeol; Go, Young Sam; Jung, Jin Hee; Suh, Mi-Chung; Kim, Jong Bum

    2011-06-01

    Ricinoleic acid (12-hydroxy-octadeca-9-enoic acid) is a major unusual fatty acid in castor oil. This hydroxy fatty acid is useful in industrial materials. This unusual fatty acid accumulates in triacylglycerol (TAG) in the seeds of the castor bean (Ricinus communis L.), even though it is synthesized in phospholipids, which indicates that the castor plant has an editing enzyme, which functions as a phospholipid:diacylglycerol acyltransferase (PDAT) that is specific to ricinoleic acid. Transgenic plants containing fatty acid Δ12-hydroxylase encoded by the castor bean FAH12 gene produce a limited amount of hydroxy fatty acid, a maximum of around 17% of TAGs present in Arabidopsis seeds, and this unusual fatty acid remains in phospholipids of cell membranes in seeds. Identification of ricinoleate-specific PDAT from castor bean and manipulation of the phospholipid editing system in transgenic plants will enhance accumulation of the hydroxy fatty acid in transgenic seeds. The castor plant has three PDAT genes; PDAT1-1 and PDAT2 are homologs of PDAT, which are commonly found in plants; however, PDAT1-2 is newly grouped as a castor bean-specific gene. PDAT1-2 is expressed in developing seeds and localized in the endoplasmic reticulum, similar to FAH12, indicating its involvement in conversion of ricinoleic acid into TAG. PDAT1-2 significantly enhances accumulation of total hydroxy fatty acid up to 25%, with a significant increase in castor-like oil, 2-OH TAG, in seeds of transgenic Arabidopsis, which is an identification of the key gene for oilseed engineering in production of unusual fatty acids.

  16. Aqueous solutions of acidic ionic liquids for enhanced stability of polyoxometalate-carbon supercapacitor electrodes

    Science.gov (United States)

    Hu, Chenchen; Zhao, Enbo; Nitta, Naoki; Magasinski, Alexandre; Berdichevsky, Gene; Yushin, Gleb

    2016-09-01

    Nanocomposites based on polyoxometalates (POMs) nanoconfined in microporous carbons have been synthesized and used as electrodes for supercapacitors. The addition of the pseudocapacitance from highly reversible redox reaction of POMs to the electric double-layer capacitance of carbon lead to an increase in specific capacitance of ∼90% at 1 mV s-1. However, high solubility of POM in traditional aqueous electrolytes leads to rapid capacity fading. Here we demonstrate that the use of aqueous solutions of protic ionic liquids (P-IL) as electrolyte instead of aqueous sulfuric acid solutions offers an opportunity to significantly improve POM cycling stability. Virtually no degradation in capacitance was observed in POM-based positive electrode after 10,000 cycles in an asymmetric capacitor with P-IL aqueous electrolyte. As such, POM-based carbon composites may now present a viable solution for enhancing energy density of electrical double layer capacitors (EDLC) based on pure carbon electrodes.

  17. Copper catalysis for enhancement of cobalt leaching and acid utilization efficiency in microbial fuel cells.

    Science.gov (United States)

    Liu, Yaxuan; Shen, Jingya; Huang, Liping; Wu, Dan

    2013-11-15

    Enhancement of both cobalt leaching from LiCoO2 and acid utilization efficiency (AUE) in microbial fuel cells (MFCs) was successfully achieved by the addition of Cu(II). A dosage of 10mg/L Cu(II) improved both cobalt leaching up to 308% and AUE of 171% compared to the controls with no presence of Cu(II). The apparent activation energy of cobalt leaching catalyzed by Cu(II) in MFCs was only 11.8 kJ/mol. These results demonstrate cobalt leaching in MFCs using Cu(II) as a catalyst may be an effective strategy for cobalt recovery and recycle of spent Li-ion batteries, and the evidence of influence factors including solid/liquid ratio, temperature, and pH and solution conductivity can contribute to improving understanding of and optimizing cobalt leaching catalyzed by Cu(II) in MFCs.

  18. Enhanced removal of 8-quinolinecarboxylic acid in an activated carbon cloth by electroadsorption in aqueous solution.

    Science.gov (United States)

    López-Bernabeu, S; Ruiz-Rosas, R; Quijada, C; Montilla, F; Morallón, E

    2016-02-01

    The effect of the electrochemical treatment (potentiostatic treatment in a filter-press electrochemical cell) on the adsorption capacity of an activated carbon cloth (ACC) was analyzed in relation with the removal of 8-quinolinecarboxylic acid pollutant from water. The adsorption capacity of an ACC is quantitatively improved in the presence of an electric field (electroadsorption process) reaching values of 96% in comparison to 55% in absence of applied potential. In addition, the cathodic treatment results in higher removal efficiencies than the anodic treatment. The enhanced adsorption capacity has been proved to be irreversible, since the removed compound remains adsorbed after switching the applied potential. The kinetics of the adsorption processes is also improved by the presence of an applied potential.

  19. Enhancing effect of dimethylamine in sulfuric acid nucleation in the presence of water – a computational study

    Directory of Open Access Journals (Sweden)

    V. Loukonen

    2010-02-01

    Full Text Available We have studied the hydration of sulfuric acid – ammonia and sulfuric acid – dimethylamine clusters using quantum chemistry. We calculated the formation energies and thermodynamics for clusters of one ammonia or one dimethylamine molecule together with 1–2 sulfuric acid and 0–5 water molecules. The results indicate that dimethylamine enhances the addition of sulfuric acid to the clusters much more efficiently than ammonia when the number of water molecules in the cluster is either zero, or greater than two. Further hydrate distribution calculations reveal that practically all dimethylamine-containing two-acid clusters will remain unhydrated in tropospherically relevant circumstances, thus strongly suggesting that dimethylamine assists atmospheric sulfuric acid nucleation much more effectively than ammonia.

  20. High saturated fatty acids proportion in Escherichia coli enhances the activity of ice-nucleation protein from Pantoea ananatis.

    Science.gov (United States)

    Yu, Feifei; Liu, Xiping; Tao, Yong; Zhu, Kun

    2013-08-01

    The ice-nucleation protein (INP) from Pantoea ananatis was expressed in Escherichia coli. INP expression increased the freezing point of the E. coli culture by a few degrees. Deletion of FabH, an important enzyme in fatty acid biosynthesis, significantly inhibited the ice-nucleation activity. Increased unsaturated fatty acids in the fabH mutant cells decreased the ice-nucleation activity. Adding exogenous saturated fatty acids increased both E. coli fatty acid saturation and the ice-nucleation activity. In contrast, adding unsaturated fatty acids exhibited the opposite effects. Furthermore, an E. coli MG1655-fadR strain with high saturated fatty acids content was constructed, in which the INP activity was enhanced by about 17% compared with its activity in the wild-type MG1655 strain.

  1. Acidic phospholipids govern the enhanced activation of IgG-B cell receptor.

    Science.gov (United States)

    Chen, Xiangjun; Pan, Weiling; Sui, Yinqiang; Li, Hua; Shi, Xiaoshan; Guo, Xingdong; Qi, Hai; Xu, Chenqi; Liu, Wanli

    2015-10-06

    B cells that express the isotype-switched IgG-B cell receptor (IgG-BCR) are one of the driving forces for antibody memory. To allow for a rapid memory IgG antibody response, IgG-BCR evolved into a highly effective signalling machine. Here, we report that the positively charged cytoplasmic domain of mIgG (mIgG-tail) specifically interacts with negatively charged acidic phospholipids. The key immunoglobulin tail tyrosine (ITT) in mIgG-tail is thus sequestered in the membrane hydrophobic core in quiescent B cells. Pre-disruption of such interaction leads to excessive recruitment of BCRs and inflated BCR signalling upon antigen stimulation, resulting in hyperproliferation of primary B cells. Physiologically, membrane-sequestered mIgG-tail can be released by antigen engagement or Ca(2+) mobilization in the initiation of B cell activation. Our studies suggest a novel regulatory mechanism for how dynamic association of mIgG-tail with acidic phospholipids governs the enhanced activation of IgG-BCR.

  2. Enhanced disease susceptibility 1 and salicylic acid act redundantly to regulate resistance gene-mediated signaling.

    Directory of Open Access Journals (Sweden)

    Srivathsa C Venugopal

    2009-07-01

    Full Text Available Resistance (R protein-associated pathways are well known to participate in defense against a variety of microbial pathogens. Salicylic acid (SA and its associated proteinaceous signaling components, including enhanced disease susceptibility 1 (EDS1, non-race-specific disease resistance 1 (NDR1, phytoalexin deficient 4 (PAD4, senescence associated gene 101 (SAG101, and EDS5, have been identified as components of resistance derived from many R proteins. Here, we show that EDS1 and SA fulfill redundant functions in defense signaling mediated by R proteins, which were thought to function independent of EDS1 and/or SA. Simultaneous mutations in EDS1 and the SA-synthesizing enzyme SID2 compromised hypersensitive response and/or resistance mediated by R proteins that contain coiled coil domains at their N-terminal ends. Furthermore, the expression of R genes and the associated defense signaling induced in response to a reduction in the level of oleic acid were also suppressed by compromising SA biosynthesis in the eds1 mutant background. The functional redundancy with SA was specific to EDS1. Results presented here redefine our understanding of the roles of EDS1 and SA in plant defense.

  3. Enhanced disease susceptibility 1 and salicylic acid act redundantly to regulate resistance gene-mediated signaling.

    Science.gov (United States)

    Venugopal, Srivathsa C; Jeong, Rae-Dong; Mandal, Mihir K; Zhu, Shifeng; Chandra-Shekara, A C; Xia, Ye; Hersh, Matthew; Stromberg, Arnold J; Navarre, DuRoy; Kachroo, Aardra; Kachroo, Pradeep

    2009-07-01

    Resistance (R) protein-associated pathways are well known to participate in defense against a variety of microbial pathogens. Salicylic acid (SA) and its associated proteinaceous signaling components, including enhanced disease susceptibility 1 (EDS1), non-race-specific disease resistance 1 (NDR1), phytoalexin deficient 4 (PAD4), senescence associated gene 101 (SAG101), and EDS5, have been identified as components of resistance derived from many R proteins. Here, we show that EDS1 and SA fulfill redundant functions in defense signaling mediated by R proteins, which were thought to function independent of EDS1 and/or SA. Simultaneous mutations in EDS1 and the SA-synthesizing enzyme SID2 compromised hypersensitive response and/or resistance mediated by R proteins that contain coiled coil domains at their N-terminal ends. Furthermore, the expression of R genes and the associated defense signaling induced in response to a reduction in the level of oleic acid were also suppressed by compromising SA biosynthesis in the eds1 mutant background. The functional redundancy with SA was specific to EDS1. Results presented here redefine our understanding of the roles of EDS1 and SA in plant defense.

  4. Electrokinetic removal of chromium and copper from contaminated soils by lactic acid enhancement in the catholyte

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dong-mei; Alshawabkeh Akram N; DENG Chang-fen; CANG Long; SI You-bin

    2004-01-01

    The electrokinetic removal of chromium and copper from contaminated soils by adding lactic acid in cathode chamber as an enhancing reagent was evaluated. Two sets of duplicate experiments with chromium contaminated kaolinite and with a silty soil sampled from a superfund site in California of USA and polluted by Cr and Cu, were carried out in a constant current mode. Changes of soil water content and soil pH before and after the electrokinetic experiments, and variations of voltage drop and electroosmosis flow during the treatments were examined. The results indicated that Cr, spiked as Cr(Ⅵ) in the kaolinite, was accumulated mainly in the anode chamber, and some of Cr and metal hydroxides precipitated in the soil sections in contact with the cathode, which significantly increased electrical energy consumption. Treatment of the soil collected from the site showed accumulation of large amounts of Cr and Cu in the anode chamber while none was detected in the cathode one. The results suggested that the two metals either complexed with the injected lactic acid at the cathode or existed as negatively charged complex, and electromigrated toward the anode under a voltage gradient.

  5. Expression of rapeseed microsomal lysophosphatidic acid acyltransferase isozymes enhances seed oil content in Arabidopsis.

    Science.gov (United States)

    Maisonneuve, Sylvie; Bessoule, Jean-Jacques; Lessire, René; Delseny, Michel; Roscoe, Thomas J

    2010-02-01

    In higher plants, lysophosphatidic acid acyltransferase (LPAAT), located in the cytoplasmic endomembrane compartment, plays an essential role in the synthesis of phosphatidic acid, a key intermediate in the biosynthesis of membrane phospholipids in all tissues and storage lipids in developing seeds. In order to assess the contribution of LPAATs to the synthesis of storage lipids, we have characterized two microsomal LPAAT isozymes, the products of homoeologous genes that are expressed in rapeseed (Brassica napus). DNA sequence homologies, complementation of a bacterial LPAAT-deficient mutant, and enzymatic properties confirmed that each of two cDNAs isolated from a Brassica napus immature embryo library encoded a functional LPAAT possessing the properties of a eukaryotic pathway enzyme. Analyses in planta revealed differences in the expression of the two genes, one of which was detected in all rapeseed tissues and during silique and seed development, whereas the expression of the second gene was restricted predominantly to siliques and developing seeds. Expression of each rapeseed LPAAT isozyme in Arabidopsis (Arabidopsis thaliana) resulted in the production of seeds characterized by a greater lipid content and seed mass. These results support the hypothesis that increasing the expression of glycerolipid acyltransferases in seeds leads to a greater flux of intermediates through the Kennedy pathway and results in enhanced triacylglycerol accumulation.

  6. Cationic amino acid transporter 2 enhances innate immunity during Helicobacter pylori infection.

    Directory of Open Access Journals (Sweden)

    Daniel P Barry

    Full Text Available Once acquired, Helicobacter pylori infection is lifelong due to an inadequate innate and adaptive immune response. Our previous studies indicate that interactions among the various pathways of arginine metabolism in the host are critical determinants of outcomes following infection. Cationic amino acid transporter 2 (CAT2 is essential for transport of L-arginine (L-Arg into monocytic immune cells during H. pylori infection. Once within the cell, this amino acid is utilized by opposing pathways that lead to elaboration of either bactericidal nitric oxide (NO produced from inducible NO synthase (iNOS, or hydrogen peroxide, which causes macrophage apoptosis, via arginase and the polyamine pathway. Because of its central role in controlling L-Arg availability in macrophages, we investigated the importance of CAT2 in vivo during H. pylori infection. CAT2(-/- mice infected for 4 months exhibited decreased gastritis and increased levels of colonization compared to wild type mice. We observed suppression of gastric macrophage levels, macrophage expression of iNOS, dendritic cell activation, and expression of granulocyte-colony stimulating factor in CAT2(-/- mice suggesting that CAT2 is involved in enhancing the innate immune response. In addition, cytokine expression in CAT2(-/- mice was altered from an antimicrobial Th1 response to a Th2 response, indicating that the transporter has downstream effects on adaptive immunity as well. These findings demonstrate that CAT2 is an important regulator of the immune response during H. pylori infection.

  7. Enhanced enzymatic hydrolysis of kenaf core using irradiation and dilute acid

    Science.gov (United States)

    Lee, Byoung-Min; Jeun, Joon-Pyo; Kang, Phil-Hyun

    2017-01-01

    This study was performed to determine the effect of electron beam dose and enzymatic hydrolysis time for production of sugar such as glucose and xylose. After kenaf core was exposed to an irradiation dose that ranged from 0 to 500 kGy, the irradiated kenaf core was treated with a 3% (v/v) sulfuric acid solution using an autoclave for 5 h at 120 °C. The pretreated kenaf core was subsequently subjected to enzymatic hydrolysis at 50 °C in a shaking water bath at 150 rpm for 12, 24, 48, and 72 h. The determined enzyme activity rates were 70 FPU (Celluclast 1.5 L) and 40 CBU (Novozyme-188). The crystallinity index decreased from 50.6% in a non-pretreated kenaf core to 27.7% in kenaf core that was subjected to the two-stage pretreatment at dose of 500 kGy. The sugar yield of the two-stage pretreated kenaf core increased with an increase in irradiation dose. The sugar yield after 72 h of enzymatic hydrolysis was 73.6% at its highest with an irradiation dose of 500 kGy. The enhancement of enzymatic hydrolysis by two-stage pretreatment was more effective than non- and single pretreatment (36.9%, 40.6% and 44.0% in non-pretreatment, electron beam and dilute acid, respectively).

  8. Enhanced 5-aminolevulinic acid-gold nanoparticle conjugate-based photodynamic therapy using pulse laser

    Science.gov (United States)

    Xu, Hao; Yao, Cuiping; Wang, Jing; Chang, Zhennan; Zhang, Zhenxi

    2016-02-01

    The low bioavailability is a crucial limitation for the application of 5-aminolevulinic acid (ALA) in theranostics. In this research, 5-aminolevulinic acid and gold nanoparticle conjugates (ALA-GNPs) were synthesized to improve the bioavailability of ALA and to investigate the impact of ALA photodynamic therapy (ALA-PDT) in Hela cells. A 532 nm pulse laser and light-emitting diode (central wavelengths 502 nm) were jointly used as light sources in PDT research. The results show a 532 nm pulse laser can control ALA release from ALA-GNPs by adjusting the pulse laser dose. This laser control release may be attributed to the heat generation from GNPs under pulse laser irradiation, which indicates accurately adjusting the pulse laser dose to control the drug release in the cell interior can be considered as a new cellular surgery modality. Furthermore, the PDT results in Hela cells indicate the enhancement of ALA release by pulse laser before PDT can promote the efficacy of cell eradication in the light-emitting diode PDT (LED-PDT). This laser mediated drug release system can provide a new online therapy approach in PDT and it can be utilized in the optical monitor technologies based individual theranostics.

  9. Phenylboronic acid-decorated gelatin nanoparticles for enhanced tumor targeting and penetration

    Science.gov (United States)

    Wang, Xin; Wei, Bing; Cheng, Xu; Wang, Jun; Tang, Rupei

    2016-09-01

    Phenylboronic acid-decorated nanoparticles (NPs) were prepared for tumor-targeted drug delivery. 3-carboxyphenylboronic acid (3-CPBA) was modified on the surface of conventional gelatin NPs (designated as NP1) to give tumor-targeting NPs (designated as NP2). The morphology and stability of NP1 and NP2 were then investigated using transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. The results show that both NP1 and NP2 are spherical-like and kinetically stable under various conditions. Doxorubicin hydrochloride (DOX) was used as a model anticancer drug and was loaded into NP1 (NP1-DOX) and NP2 (NP2-DOX). The i n vitro cellular uptake and cytotoxicity of NP1-DOX and NP2-DOX were measured using SH-SY5Y cells, H22 cells, and HepG2 cells. Tumor penetration, accumulation, and antitumor activity were investigated using SH-SY5Y tumor-like spheroids and H22 tumor-bearing mice. All results demonstrated that the conjugation of 3-CPBA can efficiently enhance non-targeted NPs’ tumor-homing activity, thus improving their tumor accumulation and antitumor effect.

  10. Citric Acid Enhanced Copper Removal by a Novel Multi-amines Decorated Resin

    Science.gov (United States)

    Ling, Chen; Liu, Fuqiang; Pei, Zhiguo; Zhang, Xiaopeng; Wei, Mengmeng; Zhang, Yanhong; Zheng, Lirong; Zhang, Jing; Li, Aimin; Xing, Baoshan

    2015-05-01

    Cu removal by a novel multi-amines decorated resin (PAMD) from wastewater in the absence or presence of citric acid (CA) was examined. Adsorption capacity of Cu onto PAMD markedly increased by 186% to 5.07 mmol/g in the presence of CA, up to 7 times of that onto four commercial resins under the same conditions. Preloaded and kinetic studies demonstrated adsorption of [Cu-CA] complex instead of CA site-bridging and variations of adsorbate species were qualitatively illustrated. The interaction configuration was further studied with ESI-MS, FTIR, XPS and XANES characterizations. The large enhancement of Cu adsorption in Cu-CA bi-solutes systems was attributed to mechanism change from single-site to dual-sites interaction in which cationic or neutral Cu species (Cu2+ and CuHL0) coordinated with neutral amine sites and anionic complex species (CuL- and Cu2L22-) directly interacted with protonated amine sites via electrostatic attraction, and the ratio of the two interactions was approximately 0.5 for the equimolar bi-solutes system. Moreover, commonly coexisting ions in wastewaters had no obvious effect on the superior performance of PAMD. Also, Cu and CA could be recovered completely with HCl. Therefore, PAMD has a great potential to efficiently remove heavy metal ions from wastewaters in the presence of organic acids.

  11. Enhanced conformational sampling of nucleic acids by a new Hamiltonian replica exchange molecular dynamics approach.

    Science.gov (United States)

    Curuksu, Jeremy; Zacharias, Martin

    2009-03-14

    Although molecular dynamics (MD) simulations have been applied frequently to study flexible molecules, the sampling of conformational states separated by barriers is limited due to currently possible simulation time scales. Replica-exchange (Rex)MD simulations that allow for exchanges between simulations performed at different temperatures (T-RexMD) can achieve improved conformational sampling. However, in the case of T-RexMD the computational demand grows rapidly with system size. A Hamiltonian RexMD method that specifically enhances coupled dihedral angle transitions has been developed. The method employs added biasing potentials as replica parameters that destabilize available dihedral substates and was applied to study coupled dihedral transitions in nucleic acid molecules. The biasing potentials can be either fixed at the beginning of the simulation or optimized during an equilibration phase. The method was extensively tested and compared to conventional MD simulations and T-RexMD simulations on an adenine dinucleotide system and on a DNA abasic site. The biasing potential RexMD method showed improved sampling of conformational substates compared to conventional MD simulations similar to T-RexMD simulations but at a fraction of the computational demand. It is well suited to study systematically the fine structure and dynamics of large nucleic acids under realistic conditions including explicit solvent and ions and can be easily extended to other types of molecules.

  12. Enhanced propionic acid degradation (EPAD) system: proof of principle and feasibility.

    Science.gov (United States)

    Ma, Jingxing; Carballa, Marta; Van De Caveye, Pieter; Verstraete, Willy

    2009-07-01

    Full-scale anaerobic single-phase digesters can be confronted with process instabilities, which often result in the accumulation of propionic acid (HPr). As a solution, an enhanced propionic acid degradation (EPAD) system has been conceptually designed and experimentally tested at lab-scale. The system consisted of two components: a liquid/solid separator containing a microfiltration membrane and an up-flow anaerobic sludge bed (UASB) reactor specialized in HPr degradation. Two lab-scale continuous stirred tank reactors (CSTR) were used, i.e. the CSTR(control) and the CSTR(treatment). Firstly, the CSTRs were stressed by organic overloading to obtain high HPr levels. During the recovery period, besides stop feeding, no actions were taken to decrease the residual HPr concentration in the CSTR(control), while the CSTR(treatment) was connected to EPAD system in order to accelerate its recovery. By the end of the experiment, the CSTR(treatment) completely recovered from HPr accumulation, while no significant decrease of the HPr level in the CSTR(control) was observed. Based on the experimental results, the up-scaling of EPAD system was evaluated and it would only account for about 2% of the volume of the full-scale digester, thus suggesting that the implementation of a mobile EPAD system in full-scale practice should be feasible.

  13. Magnetic microparticles post-synthetically coated by hyaluronic acid as an enhanced carrier for microfluidic bioanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Holubova, Lucie [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Knotek, Petr [Joint Laboratory of Solid State Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Palarcik, Jiri [Institute of Environmental and Chemical Engineering, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Cadkova, Michaela [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Belina, Petr [Department of Inorganic Technology, Faculty of Chemical Technology, University of Pardubice, Doubravice 41, 53210 Pardubice (Czech Republic); Vlcek, Milan [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovskeho sq. 2, 16206 Prague (Czech Republic); Korecka, Lucie [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Bilkova, Zuzana, E-mail: Zuzana.Bilkova@upce.cz [Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic)

    2014-11-01

    Iron oxide based particles functionalized by bioactive molecules have been utilized extensively in biotechnology and biomedicine. Despite their already proven advantages, instability under changing reaction conditions, non-specific sorption of biomolecules on the particles' surfaces, and iron oxide leakage from the naked particles can greatly limit their application. As confirmed many times, surface treatment with an appropriate stabilizer helps to minimize these disadvantages. In this work, we describe enhanced post-synthetic surface modification of superparamagnetic microparticles varying in materials and size using hyaluronic acid (HA) in various chain lengths. Scanning electron microscopy, atomic force microscopy, phase analysis light scattering and laser diffraction are the methods used for characterization of HA-coated particles. The zeta potential and thickness of HA-layer of HA-coated Dynabeads M270 Amine were − 50 mV and 85 nm, respectively, and of HA-coated p(GMA-MOEAA)-NH{sub 2} were − 38 mV and 140 nm, respectively. The electrochemical analysis confirmed the zero leakage of magnetic material and no reactivity of particles with hydrogen peroxide. The rate of non-specific sorption of bovine serum albumin was reduced up to 50% of the naked ones. The coating efficiency and suitability of biopolymer-based microparticles for magnetically active microfluidic devices were confirmed. - Highlights: • Post-synthetic surface modification of magnetic microparticles by hyaluronic acid • Hyaluronic acid — polymer of unique physicochemical and biological characteristics • Panel of particle characterization methods was introduced. • HA-coated microparticles gain characteristics suited for microfluidic bioanalysis.

  14. Enhanced transdermal delivery of 5-aminolevulinic acid and a dipeptide by iontophoresis.

    Science.gov (United States)

    Krishnan, Gayathri; Roberts, Michael S; Grice, Jeffrey; Anissimov, Yuri G; Benson, Heather A E

    2011-01-01

    Poor skin permeability limits the application of peptides to the skin. Enhanced skin permeation could facilitate the development of new therapies for dermatologic and cosmeceutical applications. The aim of this study was to investigate the application of iontophoresis to the delivery of small peptide model compounds (5-aminolevulinic acid and L-alanine-L-tryptophan) across human skin. Under the conditions tested, iontophoresis increased the in vitro permeability coefficient of ALA.HCl across human epidermis from 7 X 10(-5) cm/h with passive diffusion to 110 x 10(-5) cm/h with iontophoresis. D-Glucose permeation elucidated the iontophoretic electrotransport of ALA.HCl to have contributions of both electrorepulsion and electroosmosis. The L-alanine-L-tryptophan permeability coefficient was increased from 1.5 x 10(-5) cm/h to 35 x 10(-5) cm/h with iontophoretic application. Iontophoretic delivery of the dipeptide increased markedly at lower pH because of an increase in electrorepulsive transport. The study demonstrates that iontophoresis can enhance epidermal permeation of a small peptide and peptide-like drug by up to 15- and 22-fold under the conditions tested.

  15. Enhanced ozonation of dichloroacetic acid in aqueous solution using nanometer ZnO powders

    Institute of Scientific and Technical Information of China (English)

    Xu Zhai; Zhonglin Chen; Shuqing Zhao; He Wang; Lei Yang

    2010-01-01

    Nanometer zinc oxide (ZnO) powders were used as a catalyst to enhance the ozonation for the degradation of dichloroacetic acid (DCAA) in aqueous solution.The batch experiments were carried out to investigate the effects of key factors such as catalyst dosage,ozone dosage,solution pH and ten-butyl alcohol (t-BuOH) on the degradation efficiency of DCAA.Density functional theory (DFT) and ozonation processes were not effective for DCAA removal,and the addition of ZnO catalyst improved the degradation efficiency of DCAA during ozonation,which caused an increase of 22.8% for DCAA decomposition compared to the case of ozonation alone after 25 min.Under the same experimental conditions,the DCAA decomposition was enhanced by increasing catalyst dosage from 100 to 500 mg/L and ozone dosage from 0.83 to 3.2 mg/L,The catalytic ozonation process is more pronounced than the ozonation process alone at pH 3.93,6.88,and 10.With increasing the concentration of t-BuOH from 10 to 200 mg/L,the degradation of DCAA was significantly molecule ozone followed by the interaction of adsorbed ozone with active sites of the catalyst surface.It is also concluded that ZnO of ozone.

  16. High orientation of long chain branched poly (lactic acid) with enhanced blood compatibility and bionic structure.

    Science.gov (United States)

    Li, Zhengqiu; Ye, Lin; Zhao, Xiaowen; Coates, Phil; Caton-Rose, Fin; Martyn, Michasel

    2016-05-01

    Highly oriented poly (lactic acid) (PLA) with bionic microgrooves was fabricated through solid hot drawing technology for further improving the mechanical properties and blood biocompatibility of PLA. In order to enhance the melt strength and thus obtain high orientation degree, long chain branched PLA was prepared at first through a two-step ring-opening reaction during processing. Linear viscoelasticity combined with branch-on-branch model was used to predict probable compositions and chain topologies of the products, and it was found that the molecular weight of PLA increased and topological structures with star like chain with three arms and tree-like chain with two generations formed during reactive processing, and consequently draw ratio as high as1200% can be achieved during the subsequent hot stretching. With the increase of draw ratio, the tensile strength and orientation degree of PLA increased dramatically. Long chain branching and orientation could significantly enhance the blood compatibility of PLA by prolonging clotting time and decreasing platelet activation. Microgrooves can be observed on the surface of the oriented PLA which were similar to the intimal layer of blood vessel, and such bionic structure resulted from the formation of the oriented shish kebab-like crystals along the draw direction.

  17. Enhancement of nisin, lysozyme, and monolaurin antimicrobial activities by ethylenediaminetetraacetic acid and lactoferrin.

    Science.gov (United States)

    Branen, Jill K; Davidson, P Michael

    2004-01-01

    A microtiter plate assay was employed to systematically assess the interaction between ethylenediaminetetraacetic acid (EDTA) or lactoferrin and nisin, lysozyme, or monolaurin against strains of Listeria monocytogenes, Escherichia coli, Salmonella enteritidis, and Pseudomonas fluorescens. Low levels of EDTA acted synergistically with nisin and lysozyme against L. monocytogenes but EDTA and monolaurin interacted additively against this microorganism. EDTA synergistically enhanced the activity of nisin, monolaurin, and lysozyme in tryptic soy broth (TSB) against two enterohemorrhagic E. coli strains. In addition, various combinations of nisin, lysozyme, and monolaurin with EDTA were bactericidal to some gram-negative bacteria whereas none of the antimicrobials alone were bactericidal. Lactoferrin alone (2000 microg ml(-1)) did not inhibit any of the bacterial strains, but did enhance nisin activity against both L. monocytogenes strains. Lactoferrin in combination with monolaurin inhibited growth of E. coli O157:H7 but not E. coli O104:H21. While lactoferrin combined with nisin or monolaurin did not completely inhibit growth of the gram-negative bacteria, there was some growth inhibition. All combinations of EDTA or lactoferrin with antimicrobials were less effective in 2% fat UHT milk than in TSB. S. enteritidis and P. fluorescens strains were consistently more resistant to antimicrobial combinations. Resistance may be due to differences in the outer membrane and/or LPS structure.

  18. Free nitrous acid (FNA)-based pretreatment enhances methane production from waste activated sludge.

    Science.gov (United States)

    Wang, Qilin; Ye, Liu; Jiang, Guangming; Jensen, Paul D; Batstone, Damien J; Yuan, Zhiguo

    2013-10-15

    Anaerobic digestion of waste activated sludge (WAS) is currently enjoying renewed interest due to the potential for methane production. However, methane production is often limited by the slow hydrolysis rate and/or poor methane potential of WAS. This study presents a novel pretreatment strategy based on free nitrous acid (FNA or HNO2) to enhance methane production from WAS. Pretreatment of WAS for 24 h at FNA concentrations up to 2.13 mg N/L substantially enhanced WAS solubilization, with the highest solubilization (0.16 mg chemical oxygen demand (COD)/mg volatile solids (VS), at 2.13 mg HNO2-N/L) being six times that without FNA pretreatment (0.025 mg COD/mg VS, at 0 mg HNO2-N/L). Biochemical methane potential tests demonstrated methane production increased with increased FNA concentration used in the pretreatment step. Model-based analysis indicated FNA pretreatment improved both hydrolysis rate and methane potential, with the highest improvement being approximately 50% (from 0.16 to 0.25 d(-1)) and 27% (from 201 to 255 L CH4/kg VS added), respectively, achieved at 1.78-2.13 mg HNO2-N/L. Further analysis indicated that increased hydrolysis rate and methane potential were related to an increase in rapidly biodegradable substrates, which increased with increased FNA dose, while the slowly biodegradable substrates remained relatively static.

  19. Selection of enhanced antimicrobial activity posing lactic acid bacteria characterised by (GTG)5-PCR fingerprinting.

    Science.gov (United States)

    Šalomskienė, Joana; Abraitienė, Asta; Jonkuvienė, Dovilė; Mačionienė, Irena; Repečkienė, Jūratė

    2015-07-01

    The aim of the study was a detail evaluation of genetic diversity among the lactic acid bacteria (LAB) strains having an advantage of a starter culture in order to select genotypically diverse strains with enhanced antimicrobial effect on some harmfull and pathogenic microorganisms. Antimicrobial activity of LAB was performed by the agar well diffusion method and was examined against the reference strains and foodborne isolates of Bacillus cereus, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella Typhimurium. Antifungal activity was tested against the foodborne isolates of Candida parapsilosis, Debaromyces hansenii, Kluyveromyces marxianus, Pichia guilliermondii, Yarowia lipolytica, Aspergillus brasiliensis, Aspergillus versicolor, Cladosporium herbarum, Penicillium chrysogenum and Scopulariopsis brevicaulis. A total 40 LAB strains representing Lactobacillus (23 strains), Lactococcus (13 strains) and Streptococcus spp. (4 strains) were characterised by repetitive sequence based polymerase chain reaction fingerprinting which generated highly discriminatory profiles, confirmed the identity and revealed high genotypic heterogeneity among the strains. Many of tested LAB demonstrated strong antimicrobial activity specialised against one or few indicator strains. Twelve LAB strains were superior in suppressing growth of the whole complex of pathogenic bacteria and fungi. These results demonstrated that separate taxonomic units offered different possibilities of selection for novel LAB strains could be used as starter cultures enhancing food preservation.

  20. Extrusion enhances metabolizable energy and ileal amino acids digestibility of canola meal for broiler chickens

    Directory of Open Access Journals (Sweden)

    Aljuobori Ahmed

    2014-01-01

    Full Text Available The aim of the current study was to determine the effect of extrusion process on apparent metabolizable energy (AME, crude protein (CP and amino acid (AA digestibility of canola meal (CM in broiler chickens. A total of 36, 42-day-old broilers were randomly assigned into adaptation diets (no CM or 30% CM with six replicates. After 4 days of adaptation period, on day 47, birds were allowed to consume the assay diets that contain CM or extruded canola meal (ECM as the sole source of energy and protein. Following 4 h after feeding, the birds were killed and ileal contents were collected. The results showed that ECM had greater (P<0.001 AME (10.87 vs 9.39 MJ/kg compared to CM. The extrusion also significantly enhanced apparent ileal digestibility of CP and some of AA such as Asp, Glu, Ser, Thr and Trp. In conclusion, the extrusion treatment appeared to be a practical and effective approach in enhancing the digestibility of AME, CP and some AA of CM in broiler chickens.

  1. Reduction of endogenous kynurenic acid formation enhances extracellular glutamate, hippocampal plasticity, and cognitive behavior.

    Science.gov (United States)

    Potter, Michelle C; Elmer, Greg I; Bergeron, Richard; Albuquerque, Edson X; Guidetti, Paolo; Wu, Hui-Qiu; Schwarcz, Robert

    2010-07-01

    At endogenous brain concentrations, the astrocyte-derived metabolite kynurenic acid (KYNA) antagonizes the alpha 7 nicotinic acetylcholine receptor and, possibly, the glycine co-agonist site of the NMDA receptor. The functions of these two receptors, which are intimately involved in synaptic plasticity and cognitive processes, may, therefore, be enhanced by reductions in brain KYNA levels. This concept was tested in mice with a targeted deletion of kynurenine aminotransferase II (KAT II), a major biosynthetic enzyme of brain KYNA. At 21 days of age, KAT II knock-out mice had reduced hippocampal KYNA levels (-71%) and showed significantly increased performance in three cognitive paradigms that rely in part on the integrity of hippocampal function, namely object exploration and recognition, passive avoidance, and spatial discrimination. Moreover, compared with wild-type controls, hippocampal slices from KAT II-deficient mice showed a significant increase in the amplitude of long-term potentiation in vitro. These functional changes were accompanied by reduced extracellular KYNA (-66%) and increased extracellular glutamate (+51%) concentrations, measured by hippocampal microdialysis in vivo. Taken together, a picture emerges in which a reduction in the astrocytic formation of KYNA increases glutamatergic tone in the hippocampus and enhances cognitive abilities and synaptic plasticity. Our studies raise the prospect that interventions aimed specifically at reducing KYNA formation in the brain may constitute a promising molecular strategy for cognitive improvement in health and disease.

  2. Fatty-acid binding proteins modulate sleep and enhance long-term memory consolidation in Drosophila.

    Directory of Open Access Journals (Sweden)

    Jason R Gerstner

    Full Text Available Sleep is thought to be important for memory consolidation, since sleep deprivation has been shown to interfere with memory processing. However, the effects of augmenting sleep on memory formation are not well known, and testing the role of sleep in memory enhancement has been limited to pharmacological and behavioral approaches. Here we test the effect of overexpressing the brain-type fatty acid binding protein (Fabp7 on sleep and long-term memory (LTM formation in Drosophila melanogaster. Transgenic flies carrying the murine Fabp7 or the Drosophila homologue dFabp had reduced baseline sleep but normal LTM, while Fabp induction produced increases in both net sleep and LTM. We also define a post-training consolidation "window" that is sufficient for the observed Fabp-mediated memory enhancement. Since Fabp overexpression increases consolidated daytime sleep bouts, these data support a role for longer naps in improving memory and provide a novel role for lipid-binding proteins in regulating memory consolidation concurrently with changes in behavioral state.

  3. Hypoxia enhances the antiglioma cytotoxicity of B10, a glycosylated derivative of betulinic acid.

    Directory of Open Access Journals (Sweden)

    Sebastian Fischer

    Full Text Available B10 is a glycosylated derivative of betulinic acid with promising activity against glioma cells. Lysosomal cell death pathways appear to be essential for its cytotoxicity. We investigated the influence of hypoxia, nutrient deprivation and current standard therapies on B10 cytotoxicity. The human glioma cell lines LN-308 and LNT-229 were exposed to B10 alone or together with irradiation, temozolomide, nutrient deprivation or hypoxia. Cell growth and viability were evaluated by crystal violet staining, clonogenicity assays, propidium iodide uptake and LDH release assays. Cell death was examined using an inhibitor of lysosomal acidification (bafilomycin A1, a cathepsin inhibitor (CA074-Me and a short-hairpin RNA targeting cathepsin B. Hypoxia substantially enhanced B10-induced cell death. This effect was sensitive to bafilomycin A1 and thus dependent on hypoxia-induced lysosomal acidification. Cathepsin B appeared to mediate cell death because either the inhibitor CA074-Me or cathepsin B gene silencing rescued glioma cells from B10 toxicity under hypoxia. B10 is a novel antitumor agent with substantially enhanced cytotoxicity under hypoxia conferred by increased lysosomal cell death pathway activation. Given the importance of hypoxia for therapy resistance, malignant progression, and as a result of antiangiogenic therapies, B10 might be a promising strategy for hypoxic tumors like malignant glioma.

  4. Synergistic interactions between grafted hyaluronic acid and lubricin provide enhanced wear protection and lubrication.

    Science.gov (United States)

    Das, Saurabh; Banquy, Xavier; Zappone, Bruno; Greene, George W; Jay, Gregory D; Israelachvili, Jacob N

    2013-05-13

    Normal (e.g., adhesion) and lateral (friction) forces were measured between physisorbed and chemically grafted layers of hyaluronic acid (HA), an anionic polyelectrolyte in the presence of lubricin (Lub), a mucinous glycoprotein, on mica surfaces using a surface forces apparatus (SFA). This work demonstrates that high friction coefficients between the surfaces do not necessarily correlate with surface damage and that chemically grafted HA acts synergistically with Lub to provide friction reduction and enhanced wear protection to the surfaces. Surface immobilization of HA by grafting is necessary for such wear protection. Increasing the concentration of Lub enhances the threshold load that a chemically grafted HA surface can be subjected to before the onset of wear. Addition of Lub does not have any beneficial effect if HA is physisorbed to the mica surfaces. Damage occurs at loads less than 1 mN regardless of the amount of Lub, indicating that the molecules in the bulk play little or no role in protecting the surfaces from damage. Lub penetrates into the chemically bound HA to form a visco-elastic gel that reduces the coefficient of friction as well as boosts the strength of the surface against abrasive wear (damage).

  5. Ursolic acid regulates aging process through enhancing of metabolic sensor proteins level.

    Science.gov (United States)

    Bahrami, Soroush Alaghehband; Bakhtiari, Nuredin

    2016-08-01

    We previously reported that Ursolic Acid (UA) ameliorates skeletal muscle performance through satellite cells proliferation and cellular energy status. In studying the potential role of the hypothalamus in aging, we developed a strategy to pursue UA effects on the hypothalamus anti-aging proteins such as; SIRT1, SIRT6, PGC-1β and α-Klotho. In this study, we used a model of aging animals (C57BL/6). UA dissolved in Corn oil (20mg/ml) and then administrated (200mg/Kg i.p injection) to mice, twice daily for 7days. After treatment times, the mice perfused and the hypothalamus isolated for preparing of tissue to Immunofluorescence microscopy. The data illustrated that UA significantly increased SIRT1 (∼3.5±0.3 folds) and SIRT-6 (∼1.5±0.2 folds) proteins overexpression (Presults showed that UA enhanced α-Klotho (∼3.3±0.3) and PGC-1β (∼2.6±0.2 folds) proteins levels (PUA through enhancing of anti-aging biomarkers (SIRT1 and SIRT6) and PGC-1β in hypothalamus regulates aging-process and attenuates mitochondrial-related diseases. In regard to the key role of α-Klotho in aging, our data indicate that UA may be on the horizon to forestall diseases of aging.

  6. Endohyphal bacterium enhances production of indole-3-acetic acid by a foliar fungal endophyte.

    Science.gov (United States)

    Hoffman, Michele T; Gunatilaka, Malkanthi K; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A Elizabeth

    2013-01-01

    Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions.

  7. Enhanced fatty acid oxidation in adipocytes and macrophages reduces lipid-induced triglyceride accumulation and inflammation.

    Science.gov (United States)

    Malandrino, Maria Ida; Fucho, Raquel; Weber, Minéia; Calderon-Dominguez, María; Mir, Joan Francesc; Valcarcel, Lorea; Escoté, Xavier; Gómez-Serrano, María; Peral, Belén; Salvadó, Laia; Fernández-Veledo, Sonia; Casals, Núria; Vázquez-Carrera, Manuel; Villarroya, Francesc; Vendrell, Joan J; Serra, Dolors; Herrero, Laura

    2015-05-01

    Lipid overload in obesity and type 2 diabetes is associated with adipocyte dysfunction, inflammation, macrophage infiltration, and decreased fatty acid oxidation (FAO). Here, we report that the expression of carnitine palmitoyltransferase 1A (CPT1A), the rate-limiting enzyme in mitochondrial FAO, is higher in human adipose tissue macrophages than in adipocytes and that it is differentially expressed in visceral vs. subcutaneous adipose tissue in both an obese and a type 2 diabetes cohort. These observations led us to further investigate the potential role of CPT1A in adipocytes and macrophages. We expressed CPT1AM, a permanently active mutant form of CPT1A, in 3T3-L1 CARΔ1 adipocytes and RAW 264.7 macrophages through adenoviral infection. Enhanced FAO in palmitate-incubated adipocytes and macrophages reduced triglyceride content and inflammation, improved insulin sensitivity in adipocytes, and reduced endoplasmic reticulum stress and ROS damage in macrophages. We conclude that increasing FAO in adipocytes and macrophages improves palmitate-induced derangements. This indicates that enhancing FAO in metabolically relevant cells such as adipocytes and macrophages may be a promising strategy for the treatment of chronic inflammatory pathologies such as obesity and type 2 diabetes.

  8. Valproic acid induces cutaneous wound healing in vivo and enhances keratinocyte motility.

    Directory of Open Access Journals (Sweden)

    Soung-Hoon Lee

    Full Text Available BACKGROUND: Cutaneous wound healing is a complex process involving several signaling pathways such as the Wnt and extracellular signal-regulated kinase (ERK signaling pathways. Valproic acid (VPA is a commonly used antiepileptic drug that acts on these signaling pathways; however, the effect of VPA on cutaneous wound healing is unknown. METHODS AND FINDINGS: We created full-thickness wounds on the backs of C3H mice and then applied VPA. After 7 d, we observed marked healing and reduced wound size in VPA-treated mice. In the neo-epidermis of the wounds, β-catenin and markers for keratinocyte terminal differentiation were increased after VPA treatment. In addition, α-smooth muscle actin (α-SMA, collagen I and collagen III in the wounds were significantly increased. VPA induced proliferation and suppressed apoptosis of cells in the wounds, as determined by Ki67 and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL staining analyses, respectively. In vitro, VPA enhanced the motility of HaCaT keratinocytes by activating Wnt/β-catenin, ERK and phosphatidylinositol 3-kinase (PI3-kinase/Akt signaling pathways. CONCLUSIONS: VPA enhances cutaneous wound healing in a murine model and induces migration of HaCaT keratinocytes.

  9. Gintonin enhances performance of mice in rotarod test: Involvement of lysophosphatidic acid receptors and catecholamine release.

    Science.gov (United States)

    Lee, Byung-Hwan; Kim, Jisu; Lee, Ra Mi; Choi, Sun-Hye; Kim, Hyeon-Joong; Hwang, Sung-Hee; Lee, Myung Koo; Bae, Chun-Sik; Kim, Hyoung-Chun; Rhim, Hyewon; Lim, Kiwon; Nah, Seung-Yeol

    2016-01-26

    Ginseng has a long history of use as a tonic for restoration of vigor. One example of ginseng-derived tonic effect is that it can improve physical stamina under conditions of stress. However, the active ingredient and the underlying molecular mechanism responsible for the ergogenic effect are unknown. Recent studies show that ginseng contains a novel ingredient, gintonin, which consists of a unique class of herbal-medicine lysophosphatidic acids (LPAs). Gintonin activates G protein-coupled LPA receptors to produce a transient [Ca(2+)]i signal, which is coupled to diverse intra- and inter-cellular signal transduction pathways that stimulate hormone or neurotransmitter release. However, relatively little is known about how gintonin-mediated cellular modulation is linked to physical endurance. In the present study, systemic administration of gintonin, but not ginsenosides, in fasted mice increased blood glucose concentrations in a dose-dependent manner. Gintonin treatment elevated blood glucose to a maximum level after 30min. This elevation in blood glucose level could be abrogated by the LPA1/3 receptor antagonist, Ki16425, or the β-adrenergic receptor antagonist, propranolol. Furthermore, gintonin-dependent enhanced performance of fasted mice in rotarod test was likewise abrogated by Ki16425. Gintonin also elevated plasma epinephrine and norepinephrine concentrations. The present study shows that gintonin mediates catecholamine release through activation of the LPA receptor and that activation of the β-adrenergic receptor is coupled to liver glycogenolysis, thereby increasing the supply of glucose and enhancing performance in the rotarod test. Thus, gintonin acts via the LPA-catecholamine-glycogenolysis axis, representing a candidate mechanism that can explain how ginseng treatment enhances physical stamina.

  10. Bacterial inoculants of forage grasses that enhance degradation of 2-chlorobenzoic acid in soil

    Energy Technology Data Exchange (ETDEWEB)

    Siciliano, S.D.; Germida, J.J. [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada)

    1997-06-01

    Biological remediation of contaminated soil is an effective method of reducing risk to human and ecosystem health. Bacteria and plants might be used to enhance remediation of soil pollutants in situ. This study assessed the potential of bacteria, plants, and plant-bacteria associations to remediate 2-chlorobenzoic acid (2CBA) contaminated soil. Initially, grass viability was assessed in 2CBA-contaminated soil. Soil was contaminated with 2CBA, forage grasses were grown under growth chamber conditions for 42 or 60 d, and the 2CBA concentration in soil was determined by gas chromatography. Only five of 16 forage grasses grew in 2CBA-treated soil. Growth of Bromus inermis had no effect on 2CBA concentration, whereas Agropyron intermedium, B. biebersteinii, A. riparum, and Elymus dauricus decreased 2CBA relative to nonplanted control soil by 32 to 42%. The 12 bacteria isolates were screened for their ability to promote the germination of the five grasses in 2CBA-contaminated soil. Inoculation of A. riparum with Pseudomonas aeruginosa strain R75, a proven plant growth-promoting rhizobacterium, increased seed germination by 80% and disappearance of 2CBA by 20% relative to noninoculated plants. Inoculation of E. dauricus with a mixture of P. savastanoi strain CB35, a 2CBA-degrading bacterium, and P. aeruginosa strain R75 increased disappearance of 2CBA by 112% relative to noninoculated plants. No clear relationship between enhanced 2CBA disappearance and increased plant biomass was found. These results suggest that specific plant-microbial systems can be developed to enhance remediation of pollutants in soil.

  11. Spray-On Polyaniline/Poly(acrylic acid) Electrodes with Enhanced Electrochemical Stability.

    Science.gov (United States)

    Jeon, Ju-Won; Kwon, Se Ra; Li, Fei; Lutkenhaus, Jodie L

    2015-11-04

    Polyaniline (PANI)-based electrodes are promising candidates for energy storage, but their cycle life remains poor. Recent work suggests that secondary interactions may enhance polyaniline's electrochemical stability and cycle life, but evidence to date is not conclusive. Here, we investigate spray-assisted layer-by-layer assemblies containing polyaniline nanofibers (PANI NFs) or conventional PANI and poly(acrylic acid) (PAA), which provides hydrogen bonding and electrostatic interactions. This spray-on approach may be suitable for the deposition of PANI onto a variety of surfaces. The effects of PANI type, PAA pH, and PAA molecular weight on the growth behavior, conductivity, and electrochemical performance are examined. It is shown that LbL films with PANI NFs, higher molecular weight PAA, and lower PAA pH yield the thickest films, whereas the thinnest films come from conventional PANI assembled under similar conditions. Electron microscopy imaging and density measurements show that LbL films containing PANI NFs are very porous, whereas those containing conventional PANI are very dense (0.28 vs 1.33 g/cm(3), respectively). The difference in density dramatically affects the electrochemical properties in terms of capacity and long-term cycling behavior. Upon extended cycling, PANI NFs alone rapidly lose their electrochemical activity. On the other hand, PANI NF-based LbL films exhibited somewhat enhanced stability, and PANI-based LbL films were exceptionally stable, maintaining 94.7% of their capacity after 1000 cycles when cycled up to 4.2 V vs Li/Li(+). These results show that secondary interactions from PAA enhance stability, as does the selection of PANI type and the electrode's density.

  12. Half-dose gadoxetic acid-enhanced liver magnetic resonance imaging in patients at risk for nephrogenic systemic fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kyoung Doo [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Kim, Seong Hyun, E-mail: kshyun@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Lee, Jisun; Kang, Kyung A. [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Kim, Joungyoun; Yoo, Heejin [Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of)

    2015-03-15

    Highlights: •Half dose of gadoxetic acid achieved more than 75% enhancement degree of a standard dose. •No significant difference was observed in enhancement quality between half-dose and standard-dose MRIs for all upper abdominal organs. •Liver MRI using half-dose gadoxetic acid at 3-T can be a feasible alternative for standard-dose MRI in patients at risk for NSF. -- Abstract: Purpose: To evaluate the feasibility of half-dose gadoxetic acid (0.0125 mmol/kg) for liver MRI at 3-T compared to standard-dose (0.025 mmol/kg) in patients at risk for nephrogenic systemic fibrosis (NSF). Materials and methods: Forty patients who underwent both half-dose and standard-dose gadoxetic acid-enhanced MRIs were included. Contrast enhancement index (CEI) was calculated for liver, aorta, pancreas and kidney. Two observers independently rated and performed a one-to-one direct comparison of enhancement quality for both groups. Results: Liver CEIs were not significantly different on arterial phase between the two groups but CEIs of standard-dose MRIs were greater than half-dose MRIs on other phases (P < 0.001). CEIs were not significantly different on arterial phase for the aorta or on any phases for the pancreas. Kidney CEIs of standard-dose MRIs were greater than half-dose MRIs on all phases (P < 0.05). Enhancement quality of both groups was diagnostic and did not significantly differ for any organs. In one-to-one direct comparisons of enhancement quality, equal ratings were given in 87.5% (35/40) of cases by observer 1 and 85.0% (34/40) by observer 2. Conclusion: Liver MRI using half-dose gadoxetic acid at 3-T can be a feasible alternative for standard-dose MRI in patients at risk for NSF.

  13. Optimization of date syrup for enhancement of the production of citric acid using immobilized cells of Aspergillus niger

    OpenAIRE

    Mostafa, Yasser S.; Alamri, Saad A.

    2012-01-01

    Date syrup as an economical source of carbohydrates and immobilized Aspergillus niger J4, which was entrapped in calcium alginate pellets, were employed for enhancing the production of citric acid. Maximum production was achieved by pre-treating date syrup with 1.5% tricalcium phosphate to remove heavy metals. The production of citric acid using a pretreated medium was 38.87% higher than an untreated one that consumed sugar. The appropriate presence of nitrogen, phosphate and magnesium appear...

  14. Study of metabolic profile of Rhizopus oryzae to enhance fumaric acid production under low pH condition.

    Science.gov (United States)

    Liu, Ying; Xu, Qing; Lv, Chunwei; Yan, Caixia; Li, Shuang; Jiang, Ling; Huang, He; Ouyang, Pingkai

    2015-12-01

    Ensuring a suitable pH is a major problem in industrial organic acid fermentation. To circumvent this problem, we used a metabolic profiling approach to analyze metabolite changes in Rhizopus oryzae under different pH conditions. A correlation between fumaric acid production and intracellular metabolic characteristics of R. oryzae was revealed by principal component analysis. The results showed that to help cell survival in the presence of low pH, R. oryzae altered amino acid and fatty acid metabolism and promoted sugar or sugar alcohol synthesis, corresponding with a suppressing of energy metabolism, phenylalanine, and tyrosine synthesis and finally resulting in the low performance of fumaric acid production. Based on this observation, 1 % linoleic acid was added to the culture medium in pH 3.0 to decrease the carbon demand for cell survival, and the fumaric acid titer was enhanced by 39.7 % compared with the control (pH 3.0 without linoleic acid addition), reaching 18.3 g/L after 84 h of fermentation. These findings provide new insights into the mechanism by which R. oryzae responds to acidic stress and would be helpful for the development of efficient strategies for fumaric acid production at low pH.

  15. Gadoxetic Acid-Enhanced MR Imaging Predicts Simeprevir-Induced Hyperbilirubinemia During Hepatitis C Virus Treatment: A Pilot Study.

    Science.gov (United States)

    Okubo, Hironao; Kitamura, Tsuneo; Ando, Hitoshi; Fukada, Hiroo; Igusa, Yuki; Kokubu, Shigehiro; Miyazaki, Akihisa; Fujimura, Akio; Shiina, Shuichiro; Watanabe, Sumio

    2017-03-01

    Simeprevir is a substrate for organic anion-transporting polypeptides (OATPs) that transport bilirubin. Hyperbilirubinemia is an adverse event reported during treatment of chronic hepatitis C patients with simeprevir plus pegylated interferon and ribavirin. Because gadoxetic acid is also a substrate of OATPs, pretreatment gadoxetic acid-enhanced magnetic resonance imaging (MRI) may predict hyperbilirubinemia during treatment. This prospective study therefore evaluated 11 consecutive patients with chronic hepatitis C who underwent gadoxetic acid-enhanced MRI prior to treatment with simeprevir plus pegylated interferon and ribavirin for 12 weeks, followed by pegylated interferon and ribavirin for an additional 12 weeks. Their contrast enhancement index (CEI), an index of liver parenchymal enhancement during the hepatobiliary phase, was assessed before treatment. Plasma trough concentrations (Ctrough ) of simeprevir were determined 7 days after its administration, and serum bilirubin concentrations were measured throughout the course of treatment. Six patients (55%) developed hyperbilirubinemia (≥1.6 mg/dL) during treatment. Ctrough was significantly higher in patients with than without hyperbilirubinemia (P = .009), with a strong inverse relationship between CEI and Ctrough (r = -0.911, P simeprevir. Gadoxetic acid-enhanced magnetic resonance imaging may predict the development of hyperbilirubinemia during treatment of hepatitis C patients with simeprevir plus pegylated interferon and ribavirin.

  16. DEPOSITION TANK CORROSION TESTING FOR ENHANCED CHEMICAL CLEANING POST OXALIC ACID DESTRUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Mickalonis, J.

    2011-08-29

    An Enhanced Chemical Cleaning (ECC) process is being developed to aid in the high level waste tank closure at the Savannah River Site. The ECC process uses an advanced oxidation process (AOP) to destroy the oxalic acid that is used to remove residual sludge from a waste tank prior to closure. The AOP process treats the dissolved sludge with ozone to decompose the oxalic acid through reactions with hydroxyl radicals. The effluent from this oxalic acid decomposition is to be sent to a Type III waste tank and may be corrosive to these tanks. As part of the hazardous simulant testing that was conducted at the ECC vendor location, corrosion testing was conducted to determine the general corrosion rate for the deposition tank and to assess the susceptibility to localized corrosion, especially pitting. Both of these factors impact the calculation of hydrogen gas generation and the structural integrity of the tanks, which are considered safety class functions. The testing consisted of immersion and electrochemical testing of A537 carbon steel, the material of construction of Type III tanks, and 304L stainless steel, the material of construction for transfer piping. Tests were conducted in solutions removed from the destruction loop of the prototype ECC set up. Hazardous simulants, which were manufactured at SRNL, were used as representative sludges for F-area and H-area waste tanks. Oxalic acid concentrations of 1 and 2.5% were used to dissolve the sludge as a feed to the ECC process. Test solutions included the uninhibited effluent, as well as the effluent treated for corrosion control. The corrosion control options included mixing with an inhibited supernate and the addition of hydroxide. Evaporation of the uninhibited effluent was also tested since it may have a positive impact on reducing corrosion. All corrosion testing was conducted at 50 C. The uninhibited effluent was found to increase the corrosion rate by an order of magnitude from less than 1 mil per year (mpy

  17. Zoledronic acid enhances Vδ2 T-lymphocyte antitumor response to human glioma cell lines.

    Science.gov (United States)

    Cimini, E; Piacentini, P; Sacchi, A; Gioia, C; Leone, S; Lauro, G M; Martini, F; Agrati, C

    2011-01-01

    Glioblastoma multiforme (GBM), the most frequent and aggressive primary brain tumor in humans, responds modestly to treatment: most patients survive less than one year after diagnosis, despite both classical and innovative treatment approaches. A recent paper focused on γδ T-cell response in GBM patients, suggesting the application of an immunomodulating strategy based on γδ T-cells which is already in clinical trials for other tumors. Human Vγ2 T-cells recognize changes in the mevalonate metabolic pathway of transformed cells by activating cytotoxic response, and by cytokine and chemokine release. Interestingly, this activation may also be induced in vivo by drugs, such as zoledronic acid, that induce the accumulation of Vγ2 T-cell ligand Isopentenyl-pyrophosphate by blocking the farnesyl pyrophosphate synthase enzyme. The aim of our work is to confirm whether bisphosphonate treatment would make glioma cell lines more susceptible to lysis by in vitro expanded γδ T-cells, improving their antitumor activity. We expanded in vitro human Vγ2 T-cells by phosphoantigen stimulation and tested their activity against glioma cell lines. Co-culture with glioma cells induced Vγ2 T-cell differentiation in effector/memory cells, killing glioma cells by the release of perforin. Interestingly, glioma cells were directly affected by zoledronic acid; moreover, treatment increased their activating ability on Vγ2 T-cells, inducing an effective antitumor cytotoxic response. Taken together, our results show that aminobisphosphonate drugs may play a dual role against GBM, by directly affecting tumor cells, and by enhancing the antitumor response of Vγ2 T-cells. Our results confirm the practicability of this approach as a new immunotherapeutic strategy for GBM treatment.

  18. Enhanced mucosal re-epithelialization induced by short chain fatty acids in experimental colitis

    Directory of Open Access Journals (Sweden)

    Aguilar-Nascimento J.E.

    1999-01-01

    Full Text Available The short chain fatty acids (SCFA are the best nutrients for the colonocytes. Glucose is poorly used as a fuel but may be transformed into SCFA by colonic bacteria. The aim of this study was to investigate the effect of SCFA or glucose on experimental colitis. Colitis was induced in 30 Wistar rats by colonic instillation of 4% acetic acid. Five days later they were randomized to receive twice a day colonic lavage containing saline (controls, N = 10, 10% hypertonic glucose (N = 10 or SCFA (N = 10 until day 8 when they were killed. At autopsy, the colon was removed and weighed and the mucosa was evaluated macro- and microscopically and stripped out for DNA assay. Data are reported as mean ± SD or median [range] as appropriate. All animals lost weight but there was no difference between groups. Colon weight was significantly lower in the SCFA group (3.8 ± 0.5 g than in the control (5.3 ± 2.1 g and glucose (5.2 ± 1.3 g groups (P<0.05. Macroscopically, the severity of inflammation was less in SCFA (grade 2 [1-5] than in control (grade 9 [4-10] and glucose-treated (grade 9 [2-10] animals (P<0.01. Microscopically, ulceration of the mucosa was more severe in the glucose and control groups than in the SCFA group. The DNA content of the mucosa of SCFA-treated animals (8.2 [5.0-20.2] mg/g of tissue was higher than in glucose-treated (5.1 [4.2-8.5] mg/g of tissue; P<0.01 and control (6.2 [4.5-8.9] mg/g of tissue; P<0.05 animals. We conclude that SCFA may enhance mucosal re-epithelialization in experimental colitis, whereas hypertonic glucose is of no benefit.

  19. Hydrocaffeic acid-chitosan nanoparticles with enhanced stability, mucoadhesion and permeation properties.

    Science.gov (United States)

    Soliman, Ghareb M; Zhang, Yu Ling; Merle, Geraldine; Cerruti, Marta; Barralet, Jake

    2014-11-01

    Catechol-containing molecules, such as hydrocaffeic acid (HCA) have been shown to increase the mucoadhesion of several polymers. We report here a simple and bioinspired approach to enhance chitosan (CS) mucoadhesion and stabilize it in nanoparticulate form by preparing HCA-CS conjugates. HCA-CS conjugates containing 6 and 15mol% HCA were synthesized and characterized by FT-IR, (1)H NMR and UV-vis spectrophotometry. HCA-CS nanoparticles prepared by ionic gelation with sodium tripolyphosphate (TPP) ranged in size between 100 and 250nm depending on the polymer and TPP/CS weight ratio. In contrast to CS nanoparticles, which aggregate at pH>6.5, HCA-CS nanoparticles did not show any sign of aggregation or precipitation over the 4-10 pH range and maintain their size. Unexpectedly, HCA-CS nanoparticles also maintained their size and polydispersity index at pH 7.4 and NaCl concentrations of up to 500mM. Partial oxidation of HCA resulted in nanoparticle cross-linking and improved stability at pHnanoparticles were able to induce reversible tight junction opening in Caco-2 cell monolayers. Tight junction opening facilitated the permeability of a model hydrophilic molecule, fluorescein isothiocyanate-labeled dextran (FD4) and was 3 times higher in the cells treated with HCA-CS 15% nanoparticles compared to control groups. HCA-CS conjugates were found to be excellent candidates for stable nanodelivery systems with enhanced oral absorption of hydrophilic molecules.

  20. Extracellular Ca(2+)-dependent enhancement of cytocidal potency of zoledronic acid in human oral cancer cells.

    Science.gov (United States)

    Inoue, Sayaka; Arai, Naoya; Tomihara, Kei; Takashina, Michinori; Hattori, Yuichi; Noguchi, Makoto

    2015-08-15

    Direct antitumor effects of bisphosphonates (BPs) have been demonstrated in various cancer cells in vitro. However, the effective concentrations of BPs are typically much higher than their clinically relevant concentrations. Oral cancers frequently invade jawbone and may lead to the release of Ca(2+) in primary lesions. We investigated the effects of the combined application of zoledronic acid (ZA) and Ca(2+) on proliferation and apoptosis of oral cancer cells. Human oral cancer cells, breast cancer cells, and colon cancer cells were treated with ZA at a wide range of concentrations in different Ca(2+) concentration environments. Under a standard Ca(2+) concentration (0.6mM), micromolar concentrations of ZA were required to inhibit oral cancer cell proliferation. Increasing extracellular Ca(2+) concentrations greatly enhanced the potency of the ZA cytocidal effect. The ability of Ca(2+) to enhance the cytocidal effects of ZA was negated by the Ca(2+)-selective chelator EGTA. In contrast, the cytocidal effect of ZA was less pronounced in breast and colon cancer cells regardless of whether extracellular Ca(2+) was elevated. In oral cancer cells incubated with 1.6mM Ca(2+), ZA up-regulated mitochondrial Bax expression and increased mitochondrial Ca(2+) uptake. This was associated with decreased mitochondrial membrane potential and increased release of cytochrome c. We suggest that ZA can specifically produce potent cytocidal activity in oral cancer cells in an extracellular Ca(2+)-dependent manner, implying that BPs may be useful for treatment of oral squamous cell carcinoma with jawbone invasion leading to the hypercalcemic state.

  1. Para-aminobenzoic acid (PABA synthase enhances thermotolerance of mushroom Agaricus bisporus.

    Directory of Open Access Journals (Sweden)

    Zhonglei Lu

    Full Text Available Most mushrooms are thermo-sensitive to temperatures over 23°C, which greatly restricts their agricultural cultivation. Understanding mushroom's innate heat-tolerance mechanisms may facilitate genetic improvements of their thermotolerance. Agaricus bisporus strain 02 is a relatively thermotolerant mushroom strain, while strain 8213 is quite thermo-sensitive. Here, we compared their responses at proteomic level to heat treatment at 33°C. We identified 73 proteins that are differentially expressed between 02 and 8213 or induced upon heat stress in strain 02 itself, 48 of which with a known identity. Among them, 4 proteins are constitutively more highly expressed in 02 than 8213; and they can be further upregulated in response to heat stress in 02, but not in 8213. One protein is encoded by the para-aminobenzoic acid (PABA synthase gene Pabs, which has been shown to scavenge the reactive oxygen species in vitro. Pabs mRNA and its chemical product PABA show similar heat stress induction pattern as PABA synthase protein and are more abundant in 02, indicating transcriptional level upregulation of Pabs upon heat stress. A specific inhibitor of PABA synthesis impaired thermotolerance of 02, while exogenous PABA or transgenic overexpression of 02 derived PABA synthase enhanced thermotolerance of 8213. Furthermore, compared to 8213, 02 accumulated less H2O2 but more defense-related proteins (e.g., HSPs and Chitinase under heat stress. Together, these results demonstrate a role of PABA in enhancing mushroom thermotolerance by removing H2O2 and elevating defense-related proteins.

  2. Para-aminobenzoic acid (PABA) synthase enhances thermotolerance of mushroom Agaricus bisporus.

    Science.gov (United States)

    Lu, Zhonglei; Kong, Xiangxiang; Lu, Zhaoming; Xiao, Meixiang; Chen, Meiyuan; Zhu, Liang; Shen, Yuemao; Hu, Xiangyang; Song, Siyang

    2014-01-01

    Most mushrooms are thermo-sensitive to temperatures over 23°C, which greatly restricts their agricultural cultivation. Understanding mushroom's innate heat-tolerance mechanisms may facilitate genetic improvements of their thermotolerance. Agaricus bisporus strain 02 is a relatively thermotolerant mushroom strain, while strain 8213 is quite thermo-sensitive. Here, we compared their responses at proteomic level to heat treatment at 33°C. We identified 73 proteins that are differentially expressed between 02 and 8213 or induced upon heat stress in strain 02 itself, 48 of which with a known identity. Among them, 4 proteins are constitutively more highly expressed in 02 than 8213; and they can be further upregulated in response to heat stress in 02, but not in 8213. One protein is encoded by the para-aminobenzoic acid (PABA) synthase gene Pabs, which has been shown to scavenge the reactive oxygen species in vitro. Pabs mRNA and its chemical product PABA show similar heat stress induction pattern as PABA synthase protein and are more abundant in 02, indicating transcriptional level upregulation of Pabs upon heat stress. A specific inhibitor of PABA synthesis impaired thermotolerance of 02, while exogenous PABA or transgenic overexpression of 02 derived PABA synthase enhanced thermotolerance of 8213. Furthermore, compared to 8213, 02 accumulated less H2O2 but more defense-related proteins (e.g., HSPs and Chitinase) under heat stress. Together, these results demonstrate a role of PABA in enhancing mushroom thermotolerance by removing H2O2 and elevating defense-related proteins.

  3. Enhancing neural stem cell response to SDF-1α gradients through hyaluronic acid-laminin hydrogels.

    Science.gov (United States)

    Addington, C P; Heffernan, J M; Millar-Haskell, C S; Tucker, E W; Sirianni, R W; Stabenfeldt, S E

    2015-12-01

    Traumatic brain injury (TBI) initiates an expansive biochemical insult that is largely responsible for the long-term dysfunction associated with TBI; however, current clinical treatments fall short of addressing these underlying sequelae. Pre-clinical investigations have used stem cell transplantation with moderate success, but are plagued by staggeringly low survival and engraftment rates (2-4%). As such, providing cell transplants with the means to better dynamically respond to injury-related signals within the transplant microenvironment may afford improved transplantation survival and engraftment rates. The chemokine stromal cell-derived factor-1α (SDF-1α) is a potent chemotactic signal that is readily present after TBI. In this study, we sought to develop a transplantation vehicle to ultimately enhance the responsiveness of neural transplants to injury-induced SDF-1α. Specifically, we hypothesize that a hyaluronic acid (HA) and laminin (Lm) hydrogel would promote 1. upregulated expression of the SDF-1α receptor CXCR4 in neural progenitor/stem cells (NPSCs) and 2. enhanced NPSC migration in response to SDF-1α gradients. We demonstrated successful development of a HA-Lm hydrogel and utilized standard protein and cellular assays to probe NPSC CXCR4 expression and NPSC chemotactic migration. The findings demonstrated that NPSCs significantly increased CXCR4 expression after 48 h of culture on the HA-Lm gel in a manner critically dependent on both HA and laminin. Moreover, the HA-Lm hydrogel significantly increased NPSC chemotactic migration in response to SDF-1α at 48 h, an effect that was critically dependent on HA, laminin and the SDF-1α gradient. Therefore, this hydrogel serves to 1. prime NPSCs for the injury microenvironment and 2. provide the appropriate infrastructure to support migration into the surrounding tissue, equipping cells with the tools to more effectively respond to the injury microenvironment.

  4. Salicylic acid confers enhanced resistance to Glomerella leaf spot in apple.

    Science.gov (United States)

    Zhang, Ying; Shi, Xiangpeng; Li, Baohua; Zhang, Qingming; Liang, Wenxing; Wang, Caixia

    2016-09-01

    Glomerella leaf spot (GLS) caused by Glomerella cingulata is a newly emergent disease that results in severe defoliation and fruit spots in apple. Currently, there are no effective means to control this disease except for the traditional fungicide sprays. Induced resistance by elicitors against pathogens infection is a widely accepted eco-friendly strategy. In the present study, we investigated whether exogenous application of salicylic acid (SA) could improve resistance to GLS in a highly susceptible apple cultivar (Malus domestica Borkh. cv. 'Gala') and the underlying mechanisms. The results showed that pretreatment with SA, at 0.1-1.0 mM, induced strong resistance against GLS in 'Gala' apple leaves, with SA treated leaves showing significant reduction in lesion numbers and disease index. Concurrent with the enhanced disease resistance, SA treatment markedly increased the total antioxidant capacity (T-AOC) and defence-related enzyme activities, including catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO). As expected, SA treatment also induced the expression levels of five pathogenesis-related (PR) genes including PR1, PR5, PR8, Chitinase and β-1,3-glucanase. Furthermore, the most pronounced and/or rapid increase was observed in leaves treated with SA and subsequently inoculated with G. cingulata compared to the treatment with SA or inoculation with the pathogen. Together, these results suggest that exogenous SA triggered increase in reactive oxygen species levels and the antioxidant system might be responsible for enhanced resistance against G. cingulata in 'Gala' apple leaves.

  5. Enhanced fatty acid oxidation and FATP4 protein expression after endurance exercise training in human skeletal muscle

    DEFF Research Database (Denmark)

    Jeppesen, Jacob; Jordy, Andreas B; Sjøberg, Kim A;

    2012-01-01

    FATP1 and FATP4 appear to be important for the cellular uptake and handling of long chain fatty acids (LCFA). These findings were obtained from loss- or gain of function models. However, reports on FATP1 and FATP4 in human skeletal muscle are limited. Aerobic training enhances lipid oxidation...

  6. Interface Modification of Dye-sensitized Solar Cells with Pivalic Acid to Enhance the Open-circuit Voltage

    KAUST Repository

    Li, Xin

    2009-01-01

    Pivalic acid (PVA) was used as a new coadsorbent to dye-sensitized solar cells (DSCs) to modify the interface between the TiO2 films and electrolyte. The addition of PVA improved the light-to-electricity conversion efficiency of devices by 8% by enhancing the open-circuit voltage. Copyright © 2009 The Chemical Society of Japan.

  7. Gadoxetic acid-enhanced MRI and diffusion-weighted imaging for the detection of colorectal liver metastases after neoadjuvant chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mi Hye [Konkuk University Medical Center, Department of Radiology, Seoul (Korea, Republic of); Lee, Jeong Min; Han, Joon Koo; Choi, Byung-Ihn [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Hur, Bo Yun [Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Kim, Tae-You [Seoul National University Hospital, Department of Internal Medicine, Seoul (Korea, Republic of); Jeong, Seung-Yong; Yi, Nam-Joon; Suh, Kyung-Suk [Seoul National University Hospital, Department of Surgery, Seoul (Korea, Republic of)

    2015-08-15

    To investigate the diagnostic performance of gadoxetic acid-enhanced MRI including diffusion-weighted imaging (DWI) for the detection of colorectal liver metastases (CRLMs) after neoadjuvant chemotherapy (NAC). Our study population comprised 77 patients with 140 CRLMs who underwent gadoxetic acid-enhanced MRI within 1 month prior to surgery: group A (without NAC, n = 38) and group B (with NAC, n = 39). Two radiologists independently assessed all MR images and graded their diagnostic confidence for CRLM on a 5-point scale. Diagnostic accuracy, sensitivity and positive predictive values (PPV) were calculated and compared between the two groups. Diagnostic accuracy of gadoxetic acid-enhanced MRI in group B was slightly lower than in group A, but a statistically significant difference was not observed (observer 1: A{sub z}, 0.926 in group A, 0.905 in group B; observer 2: A{sub z}, 0.944 in group A, 0.885 in group B; p > 0.05). Sensitivity and PPV of group B were comparable to those of group A (observer 1: sensitivity = 93.5 % vs. 93.6 %, PPV = 95.1 % vs. 86.9 %; observer 2: sensitivity = 96.8 % vs. 91.0 %; PPV = 90.0 % vs. 89.7 %; all p > 0.05). Gadoxetic acid-enhanced MRI including DWI provided good diagnostic performance with high sensitivity (>90 %) for the detection of CRLMs, regardless of the influence of NAC. (orig.)

  8. Electrophilic acid gas-reactive fluid, proppant, and process for enhanced fracturing and recovery of energy producing materials

    Science.gov (United States)

    Fernandez, Carlos A.; Heldebrant, David J.; Bonneville, Alain H. R.; Jung, Hun Bok; Carroll, Kenneth

    2016-09-20

    An electrophilic acid gas-reactive fracturing and recovery fluid, proppant, and process are detailed. The fluid expands in volume to provide rapid and controlled increases in pressure that enhances fracturing in subterranean bedrock for recovery of energy-producing materials. Proppants stabilize openings in fractures and fissures following fracturing.

  9. Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol

    Science.gov (United States)

    A mixture of acetic acid, furfural and phenol (AFP), three representative lignocellulose derived inhibitors, significantly inhibited the growth and bioethanol production of Saccharomyces cerevisiae. In order to uncover mechanisms behind the enhanced tolerance of an inhibitor-tolerant S.cerevisiae s...

  10. Acetic acid enhances endurance capacity of exercise-trained mice by increasing skeletal muscle oxidative properties.

    Science.gov (United States)

    Pan, Jeong Hoon; Kim, Jun Ho; Kim, Hyung Min; Lee, Eui Seop; Shin, Dong-Hoon; Kim, Seongpil; Shin, Minkyeong; Kim, Sang Ho; Lee, Jin Hyup; Kim, Young Jun

    2015-01-01

    Acetic acid has been shown to promote glycogen replenishment in skeletal muscle during exercise training. In this study, we investigated the effects of acetic acid on endurance capacity and muscle oxidative metabolism in the exercise training using in vivo mice model. In exercised mice, acetic acid induced a significant increase in endurance capacity accompanying a reduction in visceral adipose depots. Serum levels of non-esterified fatty acid and urea nitrogen were significantly lower in acetic acid-fed mice in the exercised mice. Importantly, in the mice, acetic acid significantly increased the muscle expression of key enzymes involved in fatty acid oxidation and glycolytic-to-oxidative fiber-type transformation. Taken together, these findings suggest that acetic acid improves endurance exercise capacity by promoting muscle oxidative properties, in part through the AMPK-mediated fatty acid oxidation and provide an important basis for the application of acetic acid as a major component of novel ergogenic aids.

  11. Differentiation of intrahepatic mass-forming cholangiocarcinoma from hepatocellular carcinoma on gadoxetic acid-enhanced liver MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Rihyeon; Shin, Cheong-Il; Yoon, Jeong Hee; Joo, Ijin; Kim, Seong Ho; Hwang, Inpyeong [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Lee, Jeong Min; Han, Joon Koo [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Hospital, Institute of Radiation Medicine, Seoul (Korea, Republic of); Lee, Eun Sun; Choi, Byung Ihn [Chung-Ang University Hospital, Department of Radiology, Seoul (Korea, Republic of)

    2016-06-15

    To determine the different imaging features of intrahepatic mass-forming cholangiocarcinoma (IMCC) from hepatocellular carcinoma (HCC) on gadoxetic acid-enhanced magnetic resonance imaging (MRI). This retrospective study was institutional review board approved and the requirement for informed consent was waived. Patients who underwent gadoxetic acid-enhanced MRI with histologically confirmed IMCCs (n = 46) or HCCs (n = 58) were included. Imaging features of IMCCs and HCCs on gadoxetic acid-enhanced MRI including T2- and T1-weighted, diffusion weighted images, dynamic study and hepatobiliary phase (HBP) images were analyzed. Univariate and multivariate logistic regression analyses were performed to identify relevant differentiating features between IMCCs and HCCs. Multivariate analysis revealed heterogeneous T2 signal intensity and a hypointense rim on the HBP as suggestive findings of IMCCs and the wash-in and ''portal wash-out'' enhancement pattern as well as focal T1 high signal intensity foci as indicative of HCCs (all, p < 0.05). When we combined any three of the above four imaging features, we were able to diagnose IMCCs with 94 % (43/46) sensitivity and 86 % (50/58) specificity. Combined interpretation of enhancement characteristics including HBP images, morphologic features, and strict application of the ''portal wash-out'' pattern helped more accurate discrimination of IMCCs from HCCs. (orig.)

  12. The AMP analog AICAR modulates the Treg/Th17 axis through enhancement of fatty acid oxidation.

    Science.gov (United States)

    Gualdoni, Guido A; Mayer, Katharina A; Göschl, Lisa; Boucheron, Nicole; Ellmeier, Wilfried; Zlabinger, Gerhard J

    2016-11-01

    T cells must tightly regulate their metabolic processes to cope with varying bioenergetic demands depending on their state of differentiation. The metabolic sensor AMPK is activated in states of low energy supply and modulates cellular metabolism toward a catabolic state. Although this enzyme is known to be particularly active in regulatory T (Treg) cells, its impact on T helper (Th)-cell differentiation is poorly understood. We investigated the impact of several AMPK activators on Treg-cell differentiation and found that the direct activator AICAR (5-aminoimidazole-4-carboxamide ribonucleotide), but not the indirect activators metformin and 2-deoxyglucose, strongly enhanced Treg-cell induction by specifically enhancing Treg-cell expansion. Conversely, Th17 generation was impaired by the agent. Further investigation of the metabolic background of our observations revealed that AICAR enhanced both cellular mitochondrogenesis and fatty acid uptake. Consistently, increased Treg induction was entirely reversible on inhibition of fatty acid oxidation, thus confirming the dependence of AICAR's effects on metabolic pathways alterations. Translating our findings to an in vivo model, we found that the substance enhanced Treg cell generation on IL-2 complex-induced immune stimulation. We provide a previously unrecognized insight into the delicate interplay between immune cell function and metabolism and delineate a potential novel strategy for metabolism-targeting immunotherapy.-Gualdoni, G. A., Mayer, K. A., Göschl, L., Boucheron, N., Ellmeier, W., Zlabinger, G. J. The AMP analog AICAR modulates the Treg/Th17 axis through enhancement of fatty acid oxidation.

  13. Alkyl hydroperoxide reductase enhances the growth of Leuconostoc mesenteroides lactic acid bacteria at low temperatures.

    Science.gov (United States)

    Goto, Seitaro; Kawamoto, Jun; Sato, Satoshi B; Iki, Takashi; Watanabe, Itaru; Kudo, Kazuyuki; Esaki, Nobuyoshi; Kurihara, Tatsuo

    2015-01-01

    Lactic acid bacteria (LAB) can cause deterioration of food quality even at low temperatures. In this study, we investigated the cold-adaptation mechanism of a novel food spoilage LAB, Leuconostoc mesenteroides NH04 (NH04). L. mesenteroides was isolated from several spoiled cooked meat products at a high frequency in our factories. NH04 grew rapidly at low temperatures within the shelf-life period and resulted in heavy financial losses. NH04 grew more rapidly than related strains such as Leuconostoc mesenteroides NBRC3832 (NBRC3832) at 10°C. Proteome analysis of NH04 demonstrated that this strain produces a homolog of alkyl hydroperoxide reductase--AhpC--the expression of which can be induced at low temperatures. The expression level of AhpC in NH04 was approximately 6-fold higher than that in NBRC3832, which was grown under the same conditions. Although AhpC is known to have an anti-oxidative role in various bacteria by catalyzing the reduction of alkyl hydroperoxide and hydrogen peroxide, the involvement of AhpC in cold adaptation of food spoilage bacteria was unclear. We introduced an expression plasmid containing ahpC into NBRC3832, which grows slower than NH04 at 10°C, and found that expression of AhpC enhanced growth. These results demonstrated that AhpC, which likely increases anti-oxidative capacity of LAB, plays an important role in their rapid growth at low temperatures.

  14. Microinjection of valproic acid into the ventrolateral orbital cortex enhances stress-related memory formation.

    Directory of Open Access Journals (Sweden)

    Yan Zhao

    Full Text Available There is collecting evidence suggesting that the process of chromatin remodeling such as changes in histone acetylation contribute to the formation of stress-related memory. Recently, the ventrolateral orbital cortex (VLO, a major subdivision of orbitofrontal cortex (OFC, was shown to be involved in antidepressant-like actions through epigenetic mechanisms. Here, we further investigated the effects of the histone deacetylase inhibitor (HDACi valproic acid (VPA on stress-related memory formation and the underlying molecular mechanisms by using the traditional two-day forced swimming test (FST. The results showed that VPA significantly increased the immobility time on day 2 when infused into the VLO before the initial forced swim stress on day 1. The learned immobility response to the stress was associated with increased phosphorylation of extracellular signal-regulated kinase (ERK in VLO and hippocampus on the first day. The levels of phosphorylated ERK (phospho-ERK in VLO and hippocampus were significantly decreased when retested 24 h later. The pretreatment with intra-VLO VPA infusion further reduced the activation of ERK on day 2 and day 7 compared with the saline controls. Moreover, the VPA infusion pretreatment also induced a significantly decreased BDNF level in the VLO on day 2, whereas no change was detected in the hippocampus. These findings suggest that VPA enhance the memories of emotionally stressful events and the ERK activity is implicated in stimulating adaptive and mnemonic processes in case the event would recur.

  15. Application of hot melt extrusion to enhance the dissolution and oral bioavailability of oleanolic acid

    Directory of Open Access Journals (Sweden)

    Nannan Gao

    2017-01-01

    Full Text Available The aim of this study was to improve the in vitro dissolution rate and oral bioavailability of oleanolic acid (OA, a water insoluble drug belonging to BCS class IV. Hot melt extrusion (HME was applied to develop OA amorphous solid dispersions. The characterizations of the optimal formulation were performed by differential scanning calorimetry, X-ray powder diffraction, Fourier transform infrared spectroscopy and in vitro dissolution test. The in vivo pharmacokinetic study was conducted in rats. As a result, OA solid dispersion based on PVP VA 64 (OA-PVP was successfully prepared. In the dissolution medium containing 0.3% SDS, OA-PVP dramatically increased the releasing rate of OA compared with the physical mixture (PM-PVP and commercial tablet. Furthermore, OA-PVP exhibited higher AUC (P < 0.05 and Cmax (P < 0.05 than PM-PVP and commercial tablet. The superior dissolution property and bioavailability of OA-PVP mainly attributed to the amorphous state of OA in PVP VA64 and the well dispersion caused by thermal melting and shearing. Overall, hot melt extrusion was an efficient strategy to enhance the dissolution rate and oral bioavailability of OA.

  16. Optimization of thermal-dilute sulfuric acid pretreatment for enhancement of methane production from cassava residues.

    Science.gov (United States)

    Zhang, Qinghua; Tang, Lei; Zhang, Jianhua; Mao, Zhonggui; Jiang, Li

    2011-02-01

    In this study, the pretreatment of cassava residues by thermal-dilute sulfuric acid (TDSA) hydrolysis was investigated by means of a statistically designed set of experiments. A three-factor central composite design (CCD) was employed to identify the optimum pretreatment condition of cassava residues for methane production. The individual and interactive effects of temperature, H(2)SO(4) concentration and reaction time on increase of methane yield (IMY) were evaluated by applying response surface methodology (RSM). After optimization, the resulting optimum pretreatment condition was 157.84°C, utilizing 2.99% (w/w TS) H(2)SO(4) for 20.15 min, where the maximum methane yield (248 mL/g VS) was 56.96% higher than the control (158 mL/g VS), which was very close to the predict value 56.53%. These results indicate the model obtained through RSM analysis is suit to predict the optimum pretreatment condition and there is great potential of using TDSA pretreatment of cassava residues to enhance methane yield.

  17. Enhancement of Radiation Effects by Ursolic Acid in BGC-823 Human Adenocarcinoma Gastric Cancer Cell Line.

    Directory of Open Access Journals (Sweden)

    Yang Yang

    Full Text Available Recent research has suggested that certain plant-derived polyphenols, i.e., ursolic acid (UA, which are reported to have antitumor activities, might be used to sensitize tumor cells to radiation therapy by inhibiting pathways leading to radiation therapy resistance. This experiment was designed to investigate the effects and possible mechanism of radiosensitization by UA in BGC-823 cell line from human adenocarcinoma gastric cancer in vitro. UA caused cytotoxicity in a dose-dependent manner, and we used a sub-cytotoxicity concentration of UA to test radioenhancement efficacy with UA in gastric cancer. Radiosensitivity was determined by clonogenic survival assay. Surviving fraction of the combined group with irradiation and sub-cytotoxicity UA significantly decreased compared with the irradiation group. The improved radiosensitization efficacy was associated with enhanced G2/M arrest, increased reactive oxygen species (ROS, down-regulated Ki-67 level and improved apoptosis. In conclusion, as UA demonstrated potent antiproliferation effect and synergistic effect, it could be used as a potential drug sensitizer for the application of radiotherapy.

  18. Lignan enhancement in hairy root cultures of Linum album using coniferaldehyde and methylenedioxycinnamic acid.

    Science.gov (United States)

    Ahmadian Chashmi, Najmeh; Sharifi, Mohsen; Behmanesh, Mehrdad

    2016-07-01

    Feeding experiments with hairy root cultures of Linum album have established that the extracellular coniferaldehyde is a good precursor for production of two lignans: lariciresinol (LARI) and pinoresinol (PINO). The accumulation of the LARI, PINO, and podophyllotoxin (PTOX) in hairy roots were enhanced about 14.8-, 8.7-, and 1.5-fold (107.61, 8.7 and 6.42 µg g(-1) Fresh Wight), respectively, by the addition of coniferaldehyde (2 mM) to the culture media (after 24 hr). This result was correlated with an increase pinoresinol/lariciresinol reductase (PLR) expression gene and cinnamyl alcohol dehydrogenase (CAD) activity in the fed hairy roots. Adding 3,4-(methylendioxy)cinnamic acid (MDCA) precursor did not influence on the lignans accumulation, but the lignin content of the hairy roots was increased. Moreover, the expression genes of phenylalanine ammonialyase (PAL), CAD, and cinnamoyl-CoA reductase (CCR) were influenced after feeding hairy roots with MDCA.

  19. Reducing cannabinoid abuse and preventing relapse by enhancing endogenous brain levels of kynurenic acid

    Science.gov (United States)

    Justinova, Zuzana; Mascia, Paola; Wu, Hui-Qiu; Secci, Maria E.; Redhi, Godfrey H.; Panlilio, Leigh V.; Scherma, Maria; Barnes, Chanel; Parashos, Alexandra; Zara, Tamara; Fratta, Walter; Solinas, Marcello; Pistis, Marco; Bergman, Jack; Kangas, Brian D.; Ferré, Sergi; Tanda, Gianluigi; Schwarcz, Robert; Goldberg, Steven R.

    2013-01-01

    In the reward circuitry of the brain, alpha-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of delta-9-tetrahydrocannabinol (THC), marijuana’s main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by re-exposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are currently no medications approved for treatment of marijuana dependence. Modulation of KYNA provides a novel pharmacological strategy for achieving abstinence from marijuana and preventing relapse. PMID:24121737

  20. Enhanced Biodegradability, Lubricity and Corrosiveness of Lubricating Oil by Oleic Acid Diethanolamide Phosphate

    Directory of Open Access Journals (Sweden)

    Fang Jianhua

    2012-09-01

    Full Text Available Impacts of oleic acid diethanolamide phosphate (abbreviated as ODAP as an additive on biodegradability, anti-wear capacity, friction-reducing ability and corrosiveness of an unreadily biodegradable HVI 350 mineral lubricating oil was studied. The biodegradabilities of neat lubricating oil and its formulations with ODAP were evaluated on a biodegradation tester. Furthermore, the anti-wear and friction-reducing abilities and the corrosiveness of neat oil and the formulated oils were determined on a four-ball tribotester and a copper strip corrosion tester, respectively. The results indicated that ODAP markedly enhanced biodegradability as well as anti-wear and friction-reducing abilities of the lubricating oil. On the other hand, excellent color ratings of copper strips for both neat oil and the ODAP-doped oil were obtained in the corrosion tests, demonstrating that the corrosiveness of neat oil and the doped oil was negligible, although the latter seemed to provide slightly better anti-corrosion ability.

  1. Effects of Articular Cartilage Constituents on Phosphotungstic Acid Enhanced Micro-Computed Tomography

    Science.gov (United States)

    Karhula, Sakari S.; Finnilä, Mikko A.; Lammi, Mikko J.; Ylärinne, Janne H.; Kauppinen, Sami; Rieppo, Lassi; Pritzker, Kenneth P. H.; Nieminen, Heikki J.; Saarakkala, Simo

    2017-01-01

    Contrast-enhanced micro-computed tomography (CEμCT) with phosphotungstic acid (PTA) has shown potential for detecting collagen distribution of articular cartilage. However, the selectivity of the PTA staining to articular cartilage constituents remains to be elucidated. The aim of this study was to investigate the dependence of PTA for the collagen content in bovine articular cartilage. Adjacent bovine articular cartilage samples were treated with chondroitinase ABC and collagenase to degrade the proteoglycan and the collagen constituents in articular cartilage, respectively. Enzymatically degraded samples were compared to the untreated samples using CEμCT and reference methods, such as Fourier-transform infrared imaging. Decrease in the X-ray attenuation of PTA in articular cartilage and collagen content was observed in cartilage depth of 0–13% and deeper in tissue after collagen degradation. Increase in the X-ray attenuation of PTA was observed in the cartilage depth of 13–39% after proteoglycan degradation. The X-ray attenuation of PTA-labelled articular cartilage in CEμCT is associated mainly with collagen content but the proteoglycans have a minor effect on the X-ray attenuation of the PTA-labelled articular cartilage. In conclusion, the PTA labeling provides a feasible CEμCT method for 3D characterization of articular cartilage. PMID:28135331

  2. Enhancement of Mechanical and Thermal Properties of Polylactic Acid/Polycaprolactone Blends by Hydrophilic Nanoclay

    Directory of Open Access Journals (Sweden)

    Chern Chiet Eng

    2013-01-01

    Full Text Available The effects of hydrophilic nanoclay, Nanomer PGV, on mechanical properties of Polylactic Acid (PLA/Polycaprolactone (PCL blends were investigated and compared with hydrophobic clay, Montmorillonite K10. The PLA/PCL/clay composites were prepared by melt intercalation technique and the composites were characterized by X-ray Diffraction (XRD, Fourier Transform Infrared Spectroscopy (FTIR, Thermogravimetric Analysis (TGA, Dynamic Mechanical Analysis (DMA, Scanning Electron Microscopy (SEM, and Transmission Electron Microscopy (TEM. FTIR spectra indicated that formation of hydrogen bond between hydrophilic clay with the matrix. XRD results show that shifting of basal spacing when clay incorporated into polymer matrix. TEM micrographs reveal the formation of agglomerate in the composites. Based on mechanical properties results, addition of clay Nanomer PGV significantly enhances the flexibility of PLA/PCL blends about 136.26%. TGA showed that the presence of clay improve thermal stability of blends. DMA show the addition of clay increase storage modulus and the presence of clay Nanomer PGV slightly shift two Tg of blends become closer suggest that the presence of clay slightly compatibilizer the PLA/PCL blends. SEM micrographs revealed that presence of Nanomer PGV in blends influence the miscibility of the blends. The PLA/PCL blends become more homogeneous and consist of single phase morphology.

  3. [Enhanced reductive decoloration of methylene blue by polyacrylic acid modified zero-valent iron nanoparticles].

    Science.gov (United States)

    He, Jing; Wang, Xiang-Yu; Wang, Pei; Liu, Kun-Qian

    2015-03-01

    Nano zerovalent iron ( NZVI) technology has attracted tremendous amount of interests for degrading a number of environmental contaminants found both in surface water and underground water. However, these nanoscale particles are prone to aggregate, which may result in the decrease of its reactivity in liquid phase. Iron nanoparticles (Fe NPs) modified with polyacrylic acid (PAA) has enhanced the dispersion of NZVI and reduced its agglomeration. For the first time, PAA modified NPs (PAA-Fe NPs) were used for degradation of methylene blue in water phase. The PAA-Fe NPs prepared were characterized in terms of TEM, SEM, XRD and specific surface area. The results indicated that, the surface area of PAA-Fe NPs was increased, compared with unmodified pristine zero-valent iron NPs, and PAA-Fe NPs were smoother with smaller particle size. With addition of 0.1 g x L(-1) of PAA, the decolorization efficiency of methylene blue by PAA-Fe NPs was 98.84% in 60 min, which was 27.32% higher than that of pristine Fe NPs. Decolorization efficiencies were also affected by initial pH value, initial concentration of methylene blue, dosage of PAA-Fe NPs, and degradation temperature. Kinetic analyses based on the experimental data illustrated that the decolorization reaction of methylene blue fitted well to the pseudo first-order kinetics model.

  4. Photoluminescence Enhancement and Structure Repairing of Monolayer MoSe 2 by Hydrohalic Acid Treatment

    KAUST Repository

    Han, Hau-Vei

    2015-12-30

    Atomically thin two-dimensional transition-metal dichalcogenides (TMDCs) have attracted much attention recently due to their unique electronic and optical properties for future optoelectronic devices. The chemical vapor deposition (CVD) method is able to generate TMDCs layers with a scalable size and a controllable thickness. However, the TMDC monolayers grown by CVD may incorporate structural defects, and it is fundamentally important to understand the relation between photoluminescence and structural defects. In this report, point defects (Se vacancies) and oxidized Se defects in CVD-grown MoSe2 monolayers are identified by transmission electron microscopy and X-ray photoelectron spectroscopy. These defects can significantly trap free charge carriers and localize excitons, leading to the smearing of free band-to-band exciton emission. Here, we report that the simple hydrohalic acid treatment (such as HBr) is able to efficiently suppress the trap-state emission and promote the neutral exciton and trion emission in defective MoSe2 monolayers through the p-doping process, where the overall photoluminescence intensity at room temperature can be enhanced by a factor of 30. We show that HBr treatment is able to activate distinctive trion and free exciton emissions even from highly defective MoSe2 layers. Our results suggest that the HBr treatment not only reduces the n-doping in MoSe2 but also reduces the structural defects. The results provide further insights of the control and tailoring the exciton emission from CVD-grown monolayer TMDCs.

  5. Doping Polypyrrole Films with 4-N-Pentylphenylboronic Acid to Enhance Affinity towards Bacteria and Dopamine.

    Science.gov (United States)

    Golabi, Mohsen; Padiolleau, Laurence; Chen, Xi; Jafari, Mohammad Javad; Sheikhzadeh, Elham; Turner, Anthony P F; Jager, Edwin W H; Beni, Valerio

    2016-01-01

    Here we demonstrate the use of a functional dopant as a fast and simple way to tune the chemical affinity and selectivity of polypyrrole films. More specifically, a boronic-functionalised dopant, 4-N-Pentylphenylboronic Acid (PBA), was used to provide to polypyrrole films with enhanced affinity towards diols. In order to prove the proposed concept, two model systems were explored: (i) the capture and the electrochemical detection of dopamine and (ii) the adhesion of bacteria onto surfaces. The chemisensor, based on overoxidised polypyrrole boronic doped film, was shown to have the ability to capture and retain dopamine, thus improving its detection; furthermore the chemisensor showed better sensitivity in comparison with overoxidised perchlorate doped films. The adhesion of bacteria, Deinococcus proteolyticus, Escherichia coli, Streptococcus pneumoniae and Klebsiella pneumoniae, onto the boric doped polypyrrole film was also tested. The presence of the boronic group in the polypyrrole film was shown to favour the adhesion of sugar-rich bacterial cells when compared with a control film (Dodecyl benzenesulfonate (DBS) doped film) with similar morphological and physical properties. The presented single step synthesis approach is simple and fast, does not require the development and synthesis of functional monomers, and can be easily expanded to the electrochemical, and possibly chemical, fabrication of novel functional surfaces and interfaces with inherent pre-defined sensing and chemical properties.

  6. Diacylglycerol acyltransferase-1 inhibition enhances intestinal fatty acid oxidation and reduces energy intake in rats.

    Science.gov (United States)

    Schober, Gudrun; Arnold, Myrtha; Birtles, Susan; Buckett, Linda K; Pacheco-López, Gustavo; Turnbull, Andrew V; Langhans, Wolfgang; Mansouri, Abdelhak

    2013-05-01

    Acyl CoA:diacylglycerol acyltransferase-1 (DGAT-1) catalyzes the final step in triacylglycerol (TAG) synthesis and is highly expressed in the small intestine. Because DGAT-1 knockout mice are resistant to diet-induced obesity, we investigated the acute effects of intragastric (IG) infusion of a small molecule diacylglycerol acyltransferase-1 inhibitor (DGAT-1i) on eating, circulating fat metabolites, indirect calorimetry, and hepatic and intestinal expression of key fat catabolism enzymes in male rats adapted to an 8 h feeding-16 h deprivation schedule. Also, the DGAT-1i effect on fatty acid oxidation (FAO) was investigated in enterocyte cell culture models. IG DGAT-1i infusions reduced energy intake compared with vehicle in high-fat diet (HFD)-fed rats, but scarcely in chow-fed rats. IG DGAT-1i also blunted the postprandial increase in serum TAG and increased β-hydroxybutyrate levels only in HFD-fed rats, in which it lowered the respiratory quotient and increased intestinal, but not hepatic, protein levels of Complex III of the mitochondrial respiratory chain and of mitochondrial hydroxymethylglutaryl-CoA synthase. Finally, the DGAT-1i enhanced FAO in CaCo2 (EC50 = 0.3494) and HuTu80 (EC50 = 0.00762) cells. Thus, pharmacological DGAT-1 inhibition leads to an increase in intestinal FAO and ketogenesis when dietary fat is available. This may contribute to the observed eating-inhibitory effect.

  7. Controlled release and enhanced antibacterial activity of salicylic acid by hydrogen bonding with chitosan☆

    Institute of Scientific and Technical Information of China (English)

    Zujin Yang; Yanxiong Fang; Hongbing Ji

    2016-01-01

    Microcapsules of salicylic acid (SA) with chitosan were prepared by spray drying method. Various analytical methods were used to characterize the nature of microcapsules. Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of intermolecular interactions between chitosan and SA. Particle size analysis showed that the average size of microcapsules ranged from 2 to 20μm. Scanning electron microscopy (SEM) studies indicated that the microspheres were spherical and had a relatively smooth surface. Microbiological assay of antibacterial activity for SA and its microcapsules was measured using different bacterial strains. It was found that the antibacterial activity of SA was improved after the formation of microcapsules. The in vitro release profile showed that the microcapsules could control SA release from 1 h to 4 h. Kinetic studies revealed that the release pattern follows Korsmeyer–Peppas mechanism. Enhanced antibacterial activity of the SA micro-capsules was attributed to the synergistic effects of intermolecular hydrogen-bonding interactions N–H⋯O and O–H⋯O_C between SA and chitosan. It was also confirmed by quantum chemical calculation.

  8. Activation of ethylenediaminetetraacetic acid by a 940 nm diode laser for enhanced removal of smear layer.

    Science.gov (United States)

    Lagemann, Manfred; George, Roy; Chai, Lei; Walsh, Laurence J

    2014-08-01

    Laser enhancement of ethylenediaminetetraacetic acid with cetrimide (EDTAC) has previously been shown to increase removal of smear layer, for middle-infrared erbium lasers. This study evaluated the efficiency of EDTAC activation using a near-infrared-pulsed 940 nm laser delivered by plain fibre tips into 15% EDTAC or 3% hydrogen peroxide. Root canals in 4 groups of 10 single roots were prepared using rotary files, with controls for the presence and absence of smear layer. After laser treatment (80 mJ pulse(-1) , 50 Hz, 6 cycles of 10 s), roots were split and the apical, middle and coronal thirds of the canal were examined using scanning electron microscopy, with the area of dentine tubules determined by a validated quantitative image analysis method. Lasing EDTAC considerably improved smear layer removal, while lasing into peroxide gave minimal smear layer removal. The laser protocol used was more effective for smear layer removal than the 'gold standard' protocol using EDTAC with sodium hypochlorite (NaOCl). In addition, lasers may also provide a benefit through photothermal disinfection. Further research is needed to optimise irrigant activation protocols using near-infrared diode lasers of other wavelengths.

  9. Starter cultures and cattle feed manipulation enhance conjugated linoleic acid concentrations in Cheddar cheese.

    Science.gov (United States)

    Mohan, M S; Anand, S; Kalscheur, K F; Hassan, A N; Hippen, A R

    2013-04-01

    Conjugated linoleic acid (CLA) is a fatty acid (FA) that provides several health benefits to humans. The feeding of fish oil-supplemented diets to dairy cows has been extensively studied as a means to improve the CLA content in milk. Several studies have also been conducted on the ability of many microorganisms to produce CLA by utilizing substrates containing linoleic acid. In the present study, the dietary manipulated milk was used in combination with the CLA-producing culture to manufacture Cheddar cheese. The two diets fed to cattle were control and treatment diets to obtain control and treatment milk, respectively. The treatment diet containing fish oil (0.75% of dry matter) was fed to 32 dairy cows grouped in a pen for 18 d to increase the total CLA content in milk. Treatment milk had a CLA content of 1.60 g/100g of FA compared with 0.58 g/100g of FA in control milk obtained by feeding the control diet. A 2 × 2 factorial design with 3 replicates was used to test the combined effect of the CLA-producing starter culture of Lactococcus lactis (CI4b) versus a commercial CLA nonproducing cheese starter as the control culture, and type of milk (control vs. treatment milk) on CLA content in Cheddar cheese. Chemical composition (moisture, salt, fat, and protein) was not affected by the type of culture used. However, the age of the cheese affected the sensory properties and microbiological counts in the different treatments. Ripening with the CI4b culture was found to be effective in further enhancing the CLA content. The CI4b cheeses made from control milk and treatment milk contained 1.09 and 2.41 (±0.18) g of total CLA/100g of FA after 1 mo of ripening, which increased to 1.44 and 2.61 (±0.18) g of total CLA/100g of FA after 6 mo of ripening, respectively. The use of treatment milk resulted in an increase in the CLA isomers (trans-7,cis-9+cis-9,trans-11, trans-9,cis-11+cis-10,trans-12, trans-10,cis-12, cis-9,cis-11, trans-11,cis-13, cis-11,cis-13, trans-11,trans

  10. Water-enhanced solubility of carboxylic acids in organic solvents and its applications to extraction processes

    Energy Technology Data Exchange (ETDEWEB)

    Starr, J.N.; King, C.J.

    1991-11-01

    The solubilities of carboxylic acids in certain organic solvents increase remarkably with an increasing amount of water in the organic phase. This phenomenon leads to a novel extract regeneration process in which the co-extracted water is selectively removed from an extract, and the carboxylic acid precipitates. This approach is potentially advantageous compared to other regeneration processes because it removes a minor component of the extract in order to achieve a large recovery of acid from the extract. Carboxylic acids of interest include adipic acid, fumaric acid, and succinic acid because of their low to moderate solubilities in organic solvents. Solvents were screened for an increase in acid solubility with increased water concentration in the organic phase. Most Lewis-base solvents were found to exhibit this increased solubility phenomena. Solvents that have a carbonyl functional group showed a very large increase in acid solubility. 71 refs., 52 figs., 38 tabs.

  11. Ethylene-enhanced catabolism of ( sup 14 C)indole-3-acetic acid to indole-3-carboxylic acid in citrus leaf tissues. [Citrus sinensis

    Energy Technology Data Exchange (ETDEWEB)

    Sagee, O.; Riov, J.; Goren, J. (Hebrew Univ. of Jerusalem, Rehovot (Israel))

    1990-01-01

    Exogenous ({sup 14}C)indole-3-acetic acid (IAA) is conjugated in citrus (Citrus sinensis) leaf tissues to one major substance which has been identified as indole-3-acetylaspartic acid (IAAsp). Ethylene pretreatment enhanced the catabolism of ({sup 14}C)IAA to indole-3-carboxylic acid (ICA), which accumulated as glucose esters (ICGlu). Increased formation of ICGlu by ethylene was accompanied by a concomitant decrease in IAAsp formation. IAAsp and ICGlu were identified by combined gas chromatography-mass spectrometry. Formation of ICGlu was dependent on the concentration of ethylene and the duration of the ethylene pretreatment. It is suggested that the catabolism of IAA to ICA may be one of the mechanisms by which ethylene endogenous IAA levels.

  12. Enhanced fatty acid accumulation in Isochrysis galbana by inhibition of the mitochondrial alternative oxidase pathway under nitrogen deprivation.

    Science.gov (United States)

    Zhang, Litao; Liu, Jianguo

    2016-07-01

    The purpose of this study was to clarify the interrelation between the mitochondrial alternative oxidase (AOX) pathway and fatty acid accumulation in marine microalga Isochrysis galbana. Under normal conditions, the activity of the AOX pathway was maintained at a low level in I. galbana. Compared with the normal condition, nitrogen deprivation significantly increased the AOX pathway activity and fatty acid accumulation. Under nitrogen deprivation, the inhibition of the AOX pathway by salicylhydroxamic acid caused the accumulation of reducing equivalents and the over-reduction of chloroplasts in I. galbana cells, leading to a decrease in the photosynthetic O2 evolution rate. The over-production of reducing equivalents due to the inhibition of the AOX pathway under nitrogen deprivation further enhanced the accumulation of fatty acids in I. galbana cells.

  13. Optimization of date syrup for enhancement of the production of citric acid using immobilized cells of Aspergillus niger.

    Science.gov (United States)

    Mostafa, Yasser S; Alamri, Saad A

    2012-04-01

    Date syrup as an economical source of carbohydrates and immobilized Aspergillus niger J4, which was entrapped in calcium alginate pellets, were employed for enhancing the production of citric acid. Maximum production was achieved by pre-treating date syrup with 1.5% tricalcium phosphate to remove heavy metals. The production of citric acid using a pretreated medium was 38.87% higher than an untreated one that consumed sugar. The appropriate presence of nitrogen, phosphate and magnesium appeared to be important in order for citric acid to accumulate. The production of citric acid and the consumed sugar was higher when using 0.1% ammonium nitrate as the best source of nitrogen. The production of citric acid increased significantly when 0.1 g/l of KH2PO4 was added to the medium of date syrup. The addition of magnesium sulfate at the rate of 0.20 g/l had a stimulating effect on the production of citric acid. Maximum production of citric acid was obtained when calcium chloride was absent. One of the most important benefits of immobilized cells is their ability and stability to produce citric acid under a repeated batch culture. Over four repeated batches, the production of citric acid production was maintained for 24 days when each cycle continued for 144 h. The results obtained in the repeated batch cultivation using date syrup confirmed that date syrup could be used as a medium for the industrial production of citric acid.

  14. Ascorbic acid enhanced activation of oxygen by ferrous iron: A case of aerobic degradation of rhodamine B.

    Science.gov (United States)

    Hou, Xiaojing; Shen, Wenjuan; Huang, Xiaopeng; Ai, Zhihui; Zhang, Lizhi

    2016-05-05

    Molecular oxygen activation by ferrous ions (Fe(II)) in aqueous solution could generate reactive oxygen species (ROS) with high oxidation potential via reaction between Fe(II) and oxygen molecules (Fe(II)/air), however, ROS yielded in the Fe(II)/air process is insufficient for removal of organic pollutants due to the irreversible ferric ions (Fe(III)) accumulation. In this study, we demonstrate that ascorbic acid (AA) could enhance ROS generation via oxygen activation by ferrous irons (AA/Fe(II)/air) and thus improve the degradation of rhodamine (RhB) significantly. It was found that the first-order aerobic degradation rate of RhB in the AA/Fe(II)/air process in the presence of ascorbic acid is more than 4 times that of the Fe(II)/Air system without adding ascorbic acid. The presence of ascorbic acid could relieve the accumulation of Fe(III) by reductive accelerating the Fe(III)/Fe(II) cycles, as well as lower the redox potential of Fe(III)/Fe(II) through chelating effect, leading to enhanced ROS generation for promoting RhB degradation. This study not only sheds light on the effect of ascorbic acid on aerobic Fe(II) oxidation, but also provides a green method for effective remediation of organic pollutants.

  15. Phytotoxicity of citric acid and Tween® 80 for potential use as soil amendments in enhanced phytoremediation.

    Science.gov (United States)

    Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

    2015-01-01

    Enhanced phytoremediation adding biodegradable amendments like low molecular weight organic acids and surfactants is an interesting area of current research to overcome the limitation that represents low bioavailability of pollutants in soils. However, prior to their use in assisted phytoremediation, it is necessary to test if amendments per se exert any toxic effect to plants and to optimize their application mode. In this context, the present study assessed the effects of citric acid and Tween® 80 (polyethylene glycol sorbitan monooleate) on the development of alfalfa (Medicago sativa) plants, as influenced by their concentration and frequency of application, in order to evaluate the feasibility for their future use in enhanced phytoremediation of multi-contaminated soils. The results showed that citric acid negatively affected plant germination, while it did not have any significant effect on biomass or chlorophyll content. In turn, Tween® 80 did not affect plant germination and showed a trend to increase biomass, as well as it did not have any significant effect on chlorophyll levels. M. sativa appeared to tolerate citric acid and Tween® 80 at the tested concentrations, applied weekly. Consequently, citric acid and Tween® 80 could potentially be utilized to assist phytoremediation of contaminated soils vegetated with M. sativa.

  16. Enhanced adsorption of acidic gases (CO2, NO2 and SO2) on light metal decorated graphene oxide.

    Science.gov (United States)

    Chen, Chi; Xu, Kui; Ji, Xiao; Miao, Ling; Jiang, Jianjun

    2014-06-14

    The adsorption of several acidic gases (CO2, NO2 and SO2) on light metal (Li, Al) decorated graphene oxide (GO) is theoretically studied, based on the first-principles calculations. Configuration relaxation, binding energy and charge transfer are carried out to discuss the acidic gas adsorption ability of light metal decorated GO. It is found out that Li, Al could be anchored stably by hydroxyl and epoxy groups on GO, and then a strong adsorption of CO2, NO2 and SO2 will occur above these light metals. In contrast to Ti, Li decorated GO exhibits a comparable adsorption ability of acidic gases, but a much smaller interaction with O2 about 2.85-3.98 eV lower in binding energy; and Al decorated GO displays much higher binding energy of all acidic gases with an enhancement of about 0.59-2.29 eV. The results of enhanced acidic gas adsorption ability and a reduced interference by O2 imply that Li, Al decorated GO may be useful and promising for collection and filtration of exhaust gases.

  17. Homologous Recombination Defective Arabidopsis Mutants Exhibit Enhanced Sensitivity to Abscisic Acid

    Science.gov (United States)

    Roy, Sujit; Das, Kali Pada

    2017-01-01

    Abscisic acid (ABA) acts as an important plant hormone in regulating various aspects of plant growth and developmental processes particularly under abiotic stress conditions. An increased ABA level in plant cells inhibits DNA replication and cell division, causing plant growth retardation. In this study, we have investigated the effects of ABA on the growth responses of some major loss-of-function mutants of DNA double-stand break (DSB) repair genes in Arabidopsis during seed germination and early stages of seedling growth for understanding the role of ABA in the induction of genome instability in plants. A comparative analysis of ABA sensitivity of wild-type Arabidopsis and the knockout mutant lines related to DSB sensors, including atatm, atatr, the non-homologous end joining (NHEJ) pathway genes, and mutants related to homologous recombination (HR) pathway genes showed relatively enhanced sensitivity of atatr and HR-related mutants to ABA treatment. The expression levels of HR-related genes were increased in wild-type Arabidopsis (Col-0) during seed germination and early stages of seedling growth. Immunoblotting experiments detected phosphorylation of histone H2AX in wild-type (Col-0) and DSB repair gene mutants after ABA treatment, indicating the activation of DNA damage response due to ABA treatment. Analyses of DSB repair kinetics using comet assay under neutral condition have revealed comparatively slower DSB repair activity in HR mutants. Overall, our results have provided comprehensive information on the possible effect of ABA on DNA repair machinery in plants and also indicated potential functional involvement of HR pathway in repairing ABA induced DNA damage in Arabidopsis. PMID:28046013

  18. Enhanced production of polysialic acid by metabolic engineering of Escherichia coli.

    Science.gov (United States)

    Chen, Fang; Tao, Yong; Jin, Cheng; Xu, Yang; Lin, Bai-Xue

    2015-03-01

    A number of reports have described the production of polysialic acid (PSA), focusing on the fermentation and purification of PSA. However, little work has been done to strengthen the synthetic pathway of PSA to improve PSA production. In this study, an efficient process for enhanced production of PSA using a recombinant Escherichia coli strain was developed. To improve the PSA production efficiency, the key enzymes of PSA synthetic pathway were overexpressed separately or in combination, including N-acetylneuraminate (Neu5Ac) 7-O(or 9-O)-acetyltransferase (NeuD), CMP-Neu5Ac synthetase (NeuA), and alpha-Neu5Ac alpha-2,8-sialyltransferase (NeuS). The PSA production was significantly improved by coexpression of NeuD and NeuA. In terms of the efficiency, NeuD was considered as the most important factor. Secondly, the competing pathway of intermediate Neu5Ac was blocked by nanA deletion. The efficient PSA-producing strain E. coli SA9ΔnanA/pDB1S-DA was constructed, and 16.15 ± 1.45 g/L PSA was obtained in the fed-batch culture. The production of PSA by engineered strain was increased by 85 % compared to the original strain. These results provide evidence for improvement of PSA production by regulation of the PSA biosynthetic pathway. The high productivity of our process should make it a promising cost-effective resource for PSA.

  19. Low humic acids promote in vitro lily bulblet enlargement by enhancing roots growth and carbohydrate metabolism * #

    Science.gov (United States)

    Wu, Yun; Xia, Yi-ping; Zhang, Jia-ping; Du, Fang; Zhang, Lin; Ma, Yi-di; Zhou, Hong

    2016-01-01

    Bulblet development is a problem in global lily bulb production and carbohydrate metabolism is a crucial factor. Micropropagation acts as an efficient substitute for faster propagation and can provide a controllable condition to explore bulb growth. The present study was conducted to investigate the effects of humic acid (HA) on bulblet swelling and the carbohydrate metabolic pathway in Lilium Oriental Hybrids ‘Sorbonne’ under in vitro conditions. HA greatly promoted bulblet growth at 0.2, 2.0, and 20.0 mg/L, and pronounced increases in bulblet sucrose, total soluble sugar, and starch content were observed for higher HA concentrations (≥2.0 mg/L) within 45 d after transplanting (DAT). The activities of three major starch synthetic enzymes (including adenosine 5'-diphosphate glucose pyrophosphorylase, granule-bound starch synthase, and soluble starch synthase) were enhanced dramatically after HA application especially low concentration HA (LHA), indicating a quick response of starch metabolism. However, higher doses of HA also caused excessive aboveground biomass accumulation and inhibited root growth. Accordingly, an earlier carbon starvation emerged by observing evident starch degradation. Relative bulblet weight gradually decreased with increased HA doses and thereby broke the balance between the source and sink. A low HA concentration at 0.2 mg/L performed best in both root and bulblet growth. The number of roots and root length peaked at 14.5 and 5.75 cm, respectively. The fresh bulblet weight and diameter reached 468 mg (2.9 times that under the control treatment) and 11.68 mm, respectively. Further, sucrose/starch utilization and conversion were accelerated and carbon famine was delayed as a result with an average relative bulblet weight of 80.09%. To our knowledge, this is the first HA application and mechanism research into starch metabolism in both in vitro and in vivo condition in bulbous crops. PMID:27819136

  20. Disinfection efficiency of peracetic acid, UV and ozone after enhanced primary treatment of municipal wastewater.

    Science.gov (United States)

    Gehr, Ronald; Wagner, Monika; Veerasubramanian, Priya; Payment, Pierre

    2003-11-01

    The City of Montreal Wastewater Treatment Plant uses enhanced physicochemical processes (ferric and/or alum coagulation) for suspended solids and phosphorus removal. The objective of this study was to assess the ability of peracetic acid (PAA), UV, or ozone to inactivate the indicator organisms fecal coliforms, Enterococci, MS-2 coliphage, or Clostridium perfringens in the effluent from this plant. PAA doses to reach the target fecal coliform level of 9000 CFU/100mL exceeded 6 mg/L; similar results were obtained for enterococci, and no inactivation of Clostridium perfringens was observed. However a 1-log reduction of MS-2 occurred at PAA doses of 1.5 mg/L and higher. It was expected that this effluent would have a high ozone demand, and would require relatively high UV fluences, because of relatively high effluent COD, iron and suspended solids concentrations, and low UV transmittance. This was confirmed herein. For UV, the inactivation curve for fecal coliforms showed the typical two-stage shape, with the target of 1000 CFU/100 mL (to account for photoreactivation) occurring in the asymptote zone at fluences >20 mJ/cm(2). In contrast, inactivation curves for MS-2 and Clostridium perfringens were linear. Clostridium perfringens was the most resistant organism. For ozone, inactivation was already observed before any residuals could be measured. The transferred ozone doses to reach target fecal coliform levels ( approximately 2-log reduction) were 30-50 mg/L. MS-2 was less resistant, but Clostridium perfringens was more resistant than fecal coliforms. The different behaviour of the four indicator organisms studied, depending on the disinfectant, suggests that a single indicator organism might not be appropriate. The required dose of any of the disinfectants is unlikely to be economically viable, and upstream changes to the plant will be needed.

  1. Salicylic acid and methyl jasmonate enhance drought tolerance in chamomile plants

    Directory of Open Access Journals (Sweden)

    Nazarli Hossein

    2014-04-01

    Full Text Available Introduction: The dried flowers of chamomile contain many terpenoids and flavonoids contributing to its medicinal properties. Salicylic acid (SA and methyl jasmonate (MeJA have antioxidant properties and function as direct radical scavengers. Two Matricaria chamomilla cultivars (Bodgold and Hungary breed seeds were used in this study to investigate the effects of exogenous application of SA and MeJA on protection against drought stress as well as on changes of malone dialdehyde (MDA and electrolyte leakage index (ELI, and the fluctuation of proline and soluble sugars content in the leaves under drought stress. Methods: The experiment was conducted in a factorial design based on randomized complete blocks with three replicates. Chamomile plants were treated by two levels of drought stress as well as two different levels of MeJA (i.e., 0.0 and 100 μM and SA (i.e., 0.0 and 0.5 mM solutions. Results: There was a dramatic drought induced increase in the MDA content (128% and ELI (49% in the leaves. Deleterious effect of drought stress was more severe in untreated plants than in treated ones. Treatments with SA and MeJA significantly improved drought tolerance in chamomile plants. These treatments effectively maintained membrane integrity, thereby retarding electrolyte leakage and membrane lipid peroxidation (MDA. Treatments with SA and MeJA were also effective in enhancing the antioxidant concentrations of proline and soluble sugars. Conclusion: The production of these antioxidants could have been part of a defence system against drought damage, reducing MDA and ELI and maintaining membrane stability.

  2. Characterization of the human MSX-1 promoter and an enhancer responsible for retinoic acid induction.

    Science.gov (United States)

    Shen, R; Chen, Y; Huang, L; Vitale, E; Solursh, M

    1994-01-01

    Previous studies have shown that the expression of some human HOX genes can be induced by retinoic acid (RA) in cultured embryonal carcinoma (EC) cells. However, the mechanisms for the regulation of HOX gene expression by RA are still unclear. We have examined the effects of RA on the human MSX-1 (formerly named HOX-7) gene expression in cultured EC cells (NT2/D1). Furthermore, we have cloned and characterized the human MSX-1 promoter and analyzed the activities of the promoter in response to RA. Our results demonstrate that transcription of human MSX-1 is activated by RA in cultured EC cells. This activation is dose and time responsive. The MSX-1 promoter was shown to be TATA-box independent and able to promote transcription in RA-treated EC cells. DNase-I footprinting studies revealed protection of several GAGA factor binding sites and an NF-kappa B site upstream to the transcription start site by nuclear extracts prepared from EC cells. A downstream sequence was differentially protected by the nuclear extract from RA treated cells. This differential binding of the sequence with the nuclear extract was further confirmed by gel shift assays. This sequence confers to a heterologous promoter with the ability to respond to RA induction. Point mutation within this DNA fragment abolished the binding of the fragment to the nuclear extract and the response of this element in a heterologous promoter to RA induction. Deletion of this enhancer element together with the adjacent NF-kappa B and GAGA sites abolished the ability of the promoter to direct transcription in RA-treated EC cells. However, removal of a downstream DNA fragment from the promoter endowed the promoter with the ability to direct transcription in RA-untreated cells. Taken together, both positive and negative regulatory cis-elements are involved in the regulation of the MSX-1 promoter and coordinate to control the gene expression.

  3. n-3 polyunsaturated fatty acids supplementation enhances hippocampal functionality in aged mice

    Directory of Open Access Journals (Sweden)

    Debora eCutuli

    2014-08-01

    Full Text Available As major components of neuronal membranes, omega-3 polyunsaturated acids (n-3 PUFA exhibit a wide range of regulatory functions, modulating from synaptic plasticity to neuroinflammation, from oxidative stress to neuroprotection. Recent human and animal studies indicated the n-3 PUFA neuroprotective properties in aging, with a clear negative correlation between n-3 PUFA levels and hippocampal deficits. The present multidimensional study was aimed at associating cognition, hippocampal neurogenesis, volume, neurodegeneration and metabolic correlates to verify n-3 PUFA neuroprotective effects in aging. To this aim 19 month-old mice were given n-3 PUFA mixture, or olive oil or no dietary supplement for 8 weeks during which hippocampal-dependent mnesic functions were tested. At the end of behavioral testing morphological and metabolic correlates were analyzed. n-3 PUFA supplemented aged mice exhibited better object recognition memory, spatial and localizatory memory, and aversive response retention, without modifications in anxiety levels in comparison to controls. These improved hippocampal cognitive functions occurred in the context of an enhanced cellular plasticity and a reduced neurodegeneration. In fact, n-3 PUFA supplementation increased hippocampal neurogenesis and dendritic arborization of newborn neurons, volume, neuronal density and microglial cell number, while it decreased apoptosis, astrocytosis and lipofuscin accumulation in the hippocampus. The increased levels of some metabolic correlates (blood Acetyl-L-Carnitine and brain n-3 PUFA concentrations found in n-3 PUFA supplemented mice also pointed towards an effective neuroprotection.On the basis of the present results n-3 PUFA supplementation appears to be a useful tool in health promotion and cognitive decline prevention during aging.

  4. Ultraviolet Excitation Photothermal Spectroscopy of Non-Labeled Amino Acids and Visible Light-Induced Signal Enhancement

    Science.gov (United States)

    Hirashima, Satoshi; Harata, Akira

    2008-05-01

    A measurement system for ultraviolet-laser excitation photothermal lens spectroscopy has been designed and constructed for measuring dilute amino acids in liquid solutions. An ultraviolet laser beam is generated as the fourth harmonic of a Ti:sapphire laser in the wavelength range of 212 to 220 nm. Photothermal lens spectra of alanine, phenylalanine, serine, and tryptophan are observed. Photothermal lens spectra of these samples are coincident with their absorption spectra. It is demonstrated that photothermal lens signals of the amino acids can be amplified by simultaneous excitation with a visible laser. This ultraviolet-excitation visible-enhancement system is applicable to photoacoustic detection.

  5. SAR studies of 3-arylpropionic acids as potent and selective agonists of sphingosine-1-phosphate receptor-1 (S1P1) with enhanced pharmacokinetic properties.

    Science.gov (United States)

    Yan, Lin; Huo, Pei; Hale, Jeffrey J; Mills, Sander G; Hajdu, Richard; Keohane, Carol A; Rosenbach, Mark J; Milligan, James A; Shei, Gan-Ju; Chrebet, Gary; Bergstrom, James; Card, Deborah; Mandala, Suzanne M

    2007-02-01

    Structure-activity relationship (SAR) studies of 3-arylpropionic acids-a class of novel S1P(1) selective agonists-by introducing substitution to the propionic acid chain and replacing the adjacent phenyl ring with pyridine led to a series of modified 3-arylpropionic acids with enhanced half-life in rat. These analogs (e.g., cyclopropanecarboxylic acids) exhibited longer half-life in rat than did unmodified 3-arylpropionic acids. This result suggests that metabolic oxidation at the propionic acid chain, particularly at the C3 benzylic position of 3-arylpropionic acids, is probably responsible for their short half-life in rodent.

  6. Pretreatment of corn stover with diluted acetic acid for enhancement of acidogenic fermentation.

    Science.gov (United States)

    Zhao, Xu; Wang, Lijuan; Lu, Xuebin; Zhang, Shuting

    2014-04-01

    A Box-Behnken design of response surface method was used to optimize acetic acid-catalyzed hydrothermal pretreatment of corn stover, in respect to acid concentration (0.05-0.25%), treatment time (5-15 min) and reaction temperature (180-210°C). Acidogenic fermentations with different initial pH and hydrolyzates were also measured to evaluate the optimal pretreatment conditions for maximizing acid production. The results showed that pretreatment with 0.25% acetic acid at 191°C for 7.74 min was found to be the most optimal condition for pretreatment of corn stover under which the production of acids can reach the highest level. Acidogenic fermentation with the hydrolyzate of pretreatment at the optimal condition at the initial pH=5 was shown to be butyric acid type fermentation, producing 21.84 g acetic acid, 7.246 g propionic acid, 9.170 butyric acid and 1.035 g isovaleric acid from 100g of corn stover in 900 g of water containing 2.25 g acetic acid.

  7. Dynamic characterization of hydrophobic and hydrophilic solutes in oleic-acid enhanced transdermal delivery using two-photon fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Te-Yu; Yang, Chiu-Sheng; Chen, Yang-Fang [Department of Physics, National Taiwan University, Taipei, Taiwan (China); Tsai, Tsung-Hua [Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City, Taiwan (China); Dong, Chen-Yuan, E-mail: cydong@phys.ntu.edu.tw [Department of Physics, National Taiwan University, Taipei, Taiwan (China); Center for Quantum Science and Engineering, National Taiwan University, Taipei, Taiwan (China); Center for Optoelectronic Biomedicine, National Taiwan University, Taipei, Taiwan (China)

    2014-10-20

    In this letter, we propose an efficient methodology of investigating dynamic properties of sulforhodamine B and rhodamine B hexyl ester molecules transporting across ex-vivo human stratum corneum with and without oleic acid enhancement. Three-dimensional, time-lapse fluorescence images of the stratum corneum can be obtained using two-photon fluorescence microscopy. Furthermore, temporal quantifications of transport enhancements in diffusion parameters can be achieved with the use of Fick's second law. Dynamic characterization of solutes transporting across the stratum corneum is an effective method for understanding transient phenomena in transdermal delivery of probe molecules, leading to improved delivery strategies of molecular species for therapeutic purposes.

  8. Unexpectedly Enhanced Solubility of Aromatic Amino Acids and Peptides in an Aqueous Solution of Divalent Transition-Metal Cations

    Science.gov (United States)

    Shi, Guosheng; Dang, Yaru; Pan, Tingting; Liu, Xing; Liu, Hui; Li, Shaoxian; Zhang, Lijuan; Zhao, Hongwei; Li, Shaoping; Han, Jiaguang; Tai, Renzhong; Zhu, Yiming; Li, Jichen; Ji, Qing; Mole, R. A.; Yu, Dehong; Fang, Haiping

    2016-12-01

    We experimentally observed considerable solubility of tryptophan (Trp) in a CuCl2 aqueous solution, which could reach 2-5 times the solubility of Trp in pure water. Theoretical studies show that the strong cation-π interaction between Cu2 + and the aromatic ring in Trp modifies the electronic distribution of the aromatic ring to enhance significantly the water affinity of Trp. Similar solubility enhancement has also been observed for other divalent transition-metal cations (e.g., Zn2 + and Ni2 + ), another aromatic amino acid (phenylalanine), and three aromatic peptides (Trp-Phe, Phe-Phe, and Trp-Ala-Phe).

  9. Value of gadoxetic acid-enhanced and diffusion-weighted MR imaging in evaluation of hepatocellular carcinomas with atypical enhancement pattern on contrast-enhanced multiphasic MDCT in patients with chronic liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Su [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul (Korea, Republic of); Kim, Seong Hyun, E-mail: kshyun@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul (Korea, Republic of); Kang, Tae Wook; Song, Kyoung Doo; Choi, Dongil [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul (Korea, Republic of); Park, Cheol Keun [Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul 135-710 (Korea, Republic of)

    2015-04-15

    Highlights: •We investigated imaging findings on gadoxetic acid-enhanced MRI of HCCs without the typical enhancement pattern on multiphasic MDCT. •Most HCCs showed ancillary MR findings of typical HCC. •Considerable number of HCCs showed MR enhancement pattern of typical HCC. -- Abstract: Objective: The purpose of this study was to investigate the value of enhancement kinetics and ancillary imaging findings on gadoxetic acid-enhanced and diffusion-weighted (DW) MR imaging for diagnosing hepatocellular carcinomas (HCCs) without the typical enhancement pattern on contrast-enhanced multiphasic MDCT in patients with chronic liver disease. Materials and methods: Eighty-two surgically confirmed HCCs without the typical enhancement pattern (hypervascular in the arterial phase, followed by washout on the portal or equilibrium phases) on triple-phase MDCT were enrolled in this study. The patients were classified into four categories based on the CT density pattern of arterial and equilibrium phases (isodense–isodense, hypodense–hypodense, isodense–hypodense, and hyperdense–isodense) compared to liver parenchyma. Signal intensity of HCCs on T2-weighted images (T2WI), arterial phase, 3 min late-phase, hepatobiliary phase (HBP) and DW images with a b value of 800 s/mm{sup 2} were qualitatively evaluated, and ADC values were measured. Fisher's exact test and Chi-square test were used to compare the frequency and trend of hyperintensity on T2WI, hypointensity on HBP images, hyperintensity on DW images, and histopathologic grades between groups with different CT density patterns. Kruskal–Wallis test was used to compare the ADC value between groups. Results: Thirty and 52 HCCs were categorized as hypervascular (hyperdense–isodense) and non-hypervascular HCCs (3, isodense–isodense; 37, hypodense–hypodense; 12, isodense–hypodense), respectively. Most HCCs showed hyperintensity on T2WI (77/82, 93.9%) and DW images (81/82, 98.8%) and hypointensity on HBP

  10. Nordihydroguaiaretic acid enhances the activities of aminoglycosides against methicillin- sensitive and resistant Staphylococcus aureus in vitro and in vivo

    OpenAIRE

    Edward eCunningham-Oakes; Odel eSoren; Caroline eMoussa; Getika eRathor; Yingjun eLiu; Anthony eCoates; Yanmin eHu

    2015-01-01

    Infections caused by methicillin-sensitive (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) are prevalent. MRSA infections are difficult to treat and there are no new classes of antibiotics produced to the market to treat infections caused by the resistant bacteria. Therefore, using antibiotic enhancers to rescue existing classes of antibiotics is an attractive strategy. Nordihydroguaiaretic acid (NDGA) is an antioxidant compound found in extracts from plant Larrea Tridentata. ...

  11. Nordihydroguaiaretic acid enhances the activities of aminoglycosides against methicillin- sensitive and resistant Staphylococcus aureus in vitro and in vivo

    OpenAIRE

    Cunningham-Oakes, Edward; Soren, Odel; Moussa, Caroline; Rathor, Getika; Liu, Yingjun; Coates, Anthony; Hu, Yanmin

    2015-01-01

    Infections caused by methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) are prevalent. MRSA infections are difficult to treat and there are no new classes of antibiotics produced to the market to treat infections caused by the resistant bacteria. Therefore, using antibiotic enhancers to rescue existing classes of antibiotics is an attractive strategy. Nordihydroguaiaretic acid (NDGA) is an antioxidant compound found in extracts from plant Larrea Trid...

  12. Significant enhancement of fatty acid composition in seeds of the allohexaploid, Camelina sativa, using CRISPR/Cas9 gene editing.

    Science.gov (United States)

    Jiang, Wen Zhi; Henry, Isabelle M; Lynagh, Peter G; Comai, Luca; Cahoon, Edgar B; Weeks, Donald P

    2016-11-11

    The CRISPR/Cas9 nuclease system is a powerful and flexible tool for genome editing, and novel applications of this system are being developed rapidly. Here, we used CRISPR/Cas9 to target the FAD2 gene in Arabidopsis thaliana and in the closely related emerging oil seed plant, Camelina sativa, with the goal of improving seed oil composition. We successfully obtained Camelina seeds in which oleic acid content was increased from 16% to over 50% of the fatty acid composition. These increases were associated with significant decreases in the less desirable polyunsaturated fatty acids, linoleic acid (i.e. a decrease from ~16% to <4%) and linolenic acid (a decrease from ~35% to <10%). These changes result in oils that are superior on multiple levels: they are healthier, more oxidatively stable and better suited for production of certain commercial chemicals, including biofuels. As expected, A. thaliana T2 and T3 generation seeds exhibiting these types of altered fatty acid profiles were homozygous for disrupted FAD2 alleles. In the allohexaploid, Camelina, guide RNAs were designed that simultaneously targeted all three homoeologous FAD2 genes. This strategy that significantly enhanced oil composition in T3 and T4 generation Camelina seeds was associated with a combination of germ-line mutations and somatic cell mutations in FAD2 genes in each of the three Camelina subgenomes.

  13. Enhanced phenylpyruvic acid production with Proteus vulgaris in fed-batch and continuous fermentation.

    Science.gov (United States)

    Coban, Hasan B; Demirci, Ali; Patterson, Paul H; Elias, Ryan J

    2016-01-01

    Phenylpyruvic acid is a deaminated form of phenylalanine and is used in various areas such as development of cheese and wine flavors, diagnosis of phenylketonuria, and to decrease excessive nitrogen accumulation in the manure of farm animals. However, reported phenylpyruvic acid fermentation studies in the literature have been usually performed at shake-flask scale with low production. In this study, phenylpyruvic acid production was evaluated in bench-top bioreactors by conducting fed-batch and continuous fermentation for the first time. As a result, maximum phenylpyruvic acid concentrations increased from 1350 mg/L (batch fermentation) to 2958 mg/L utilizing fed-batch fermentation. Furthermore, phenylpyruvic acid productivity was increased from 48 mg/L/hr (batch fermentation) to 104 and 259 mg/L/hr by conducting fed-batch and continuous fermentation, respectively. Overall, this study demonstrated that fed-batch and continuous fermentation significantly improved phenylpyruvic acid production in bench-scale bioreactor production.

  14. Surface plasmon resonance-enhanced fluorescence implementation of a single-step competition assay: demonstration of fatty acid measurement using an anti-fatty acid monoclonal antibody and a Cy5-labeled fatty acid.

    Science.gov (United States)

    Vareiro, Margarida M L M; Tranchant, Isabelle; Maplin, Sandra; Zak, Kris; Gani, M M; Slevin, Christopher J; Hailes, Helen C; Tabor, Alethea B; Cameron, Petra J; Jenkins, A Toby A; Williams, David E

    2008-06-15

    The development of a single-step, separation-free method for measurement of low concentrations of fatty acid using a surface plasmon resonance-enhanced fluorescence competition assay with a surface-bound antibody is described. The assay behavior was unexpectedly complex. A nonlinear coverage-dependent self-quenching of emission from surface-bound fluorescent label was deduced from the response kinetics and attributed to a surface plasmon-mediated energy transfer between adsorbed fluorophores, modified by the effects of plasmon interference. Principles of assay design to avoid complications from such effects are discussed. An anti-fatty acid mouse monoclonal antibody reacting to the alkyl chain was prepared and supported on a gold chip at a spacing appropriate for surface-plasmon field-enhanced fluorescence spectroscopy (SPEFS), by applying successively a self-assembled biotinylated monolayer, then streptavidin, then biotinylated protein A, and then the antibody, which was crosslinked to the protein A. Synthesis of a fluorescently (Cy5) tagged C-11 fatty acid is reported. SPEFS was used to follow the kinetics of the binding of the labeled fatty acid to the antibody, and to implement a competition assay with free fatty acid (undecanoic acid), sensitive at the 1 microM scale, a sensitivity limit caused by the low affinity of antibodies for free fatty acids, rather than the SPEFS technique itself. Free fatty acid concentration in human serum is in the range 0.1-1mM, suggesting that this measurement approach could be applied in a clinical diagnostic context. Finally, a predictive, theoretical model of fatty acid binding was developed that accounted for the observed "overshoot" kinetics.

  15. Inhibition of oxidative phosphorylation for enhancing citric acid production by Aspergillus niger

    OpenAIRE

    Wang, Lu; Zhang, Jianhua; Cao, Zhanglei; Wang, Yajun; Gao, Qiang; Zhang, Jian; Wang, Depei

    2015-01-01

    Background The spore germination rate and growth characteristics were compared between the citric acid high-yield strain Aspergillus niger CGMCC 5751 and A. niger ATCC 1015 in media containing antimycin A or DNP. We inferred that differences in citric acid yield might be due to differences in energy metabolism between these strains. To explore the impact of energy metabolism on citric acid production, the changes in intracellular ATP, NADH and NADH/NAD+ were measured at various fermentation s...

  16. Use of potassium-form cation-exchange resin as a conductimetric enhancer in ion-exclusion chromatography of aliphatic carboxylic acids.

    Science.gov (United States)

    Iwata, Tomotaka; Mori, Masanobu; Itabashi, Hideyuki; Tanaka, Kazuhiko

    2009-09-15

    In this study, a cation-exchange resin (CEX) of the K(+)-form, i.e., an enhancer resin, is used as a postcolumn conductimetric enhancer in the ion-exclusion chromatography of aliphatic carboxylic acids. The enhancer resin is filled in the switching valve of an ion chromatograph; this valve is usually used as a suppressor valve in ion-exchange chromatography. An aliphatic carboxylic acid (e.g., CH(3)COOH) separated by a weakly acidic CEX column of the H(+)-form converts into that of the K(+)-form (e.g., CH(3)COOK) by passing through the enhancer resin. In contrast, the background conductivity decreases because a strong acid (e.g., HNO(3)) with a higher conductimetric response in an eluent converts into a salt (e.g., KNO(3)) with a lower conductimetric response. Since the pH of the eluent containing the resin enhancer increases from 3.27 to 5.85, the enhancer accelerates the dissociations of analyte acids. Consequently, peak heights and peak areas of aliphatic carboxylic acids (e.g., acetic acid, propionic acid, butyric acid, and valeric acid) with the enhancer resin are 6.3-8.0 times higher and 7.2-9.2 times larger, respectively, than those without the enhancer resin. Calibrations of peak areas for injected analytes are linear in the concentration range of 0.01-1.0mM. The detection limits (signal-to-noise ratio=3) range from 0.10 microM to 0.39 microM in this system, as opposed to those in the range of 0.24-7.1 microM in the separation column alone. The developed system is successfully applied to the determination of aliphatic carboxylic acids in a chicken droppings sample.

  17. Liver-targeting self-assembled hyaluronic acid-glycyrrhetinic acid micelles enhance hepato-protective effect of silybin after oral administration.

    Science.gov (United States)

    Han, Xiaofeng; Wang, Zhe; Wang, Manyuan; Li, Jing; Xu, Yongsong; He, Rui; Guan, Hongyu; Yue, Zhujun; Gong, Muxin

    2016-06-01

    In order to enhance oral bioavailability and liver targeting delivery of silybin, two amphiphilic hyaluronic acid derivatives, hyaluronic acid-deoxycholic acid (HA-adh-DOCA) and hyaluronic acid-glycyrrhetinic acid (HA-adh-GA) conjugates, were designed and synthesized. Silybin was successfully loaded in HA-adh-DOCA and HA-adh-GA micelles with high drug-loading capacities (20.3% ± 0.5% and 20.6% ± 0.6%, respectively). The silybin-loaded micelles were spherical in shape with the average size around 130 nm. In vitro release study showed that two silybin-loaded micelles displayed similar steady continued-release pattern in simulated gastrointestinal fluids and PBS. Single-pass intestinal perfusion studies indicated that silybin-loaded micelles were absorbed in the whole intestine and transported via a passive diffusion mechanism. Compared with suspension formulation, silybin-loaded HA-adh-DOCA and HA-adh-GA micelles achieved significantly higher AUC and Cmax level. Moreover, liver targeting drug delivery of micelles was confirmed by in vivo imaging analysis. In comparison between the two micellar formulations, HA-adh-GA micelles possessed higher targeting capacity than HA-adh-DOCA micelles, owing to the active hepatic targeting properties of glycyrrhetinic acid. In the treatment of acute liver injury induced by CCl4, silybin-loaded HA-adh-GA micelles displayed better effects over suspension control and silybin-loaded HA-adh-DOCA micelles. Overall, pharmaceutical and pharmacological indicators suggested that the HA-adh-GA conjugates can be successfully utilized for liver targeting of orally administered therapeutics.

  18. Enhancing the capacitances of electric double layer capacitors based on carbon nanotube electrodes by carbon dioxide activation and acid oxidization

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polarizable electrodes of electric double layer capacitors(EDLCs) were made from carbon nanotubes(CNTs).Effect of carbon dioxide activation together with acid oxidation for the electrodes on the characteristics and performances of electrodes and EDLCs was studied.Carbon dioxide activation changed the microstructure of the electrodes,increased the effective surface area of CNTs and optimized the distribution of apertures of the electrodes.Acid oxidization modified the surface characteristics of CNTs.Based on the polarizable electrodes treated by carbon dioxide activation and acid oxidization,the performances of EDLCs were greatly enhanced.The specific capacitance of the electrodes with organic electrolyte was increased from 21.8 F/g to 60.4 F/g.

  19. Enhanced enzymatic hydrolysis of poplar bark by combined use of gamma ray and dilute acid for bioethanol production

    Science.gov (United States)

    Chung, Byung Yeoup; Lee, Jae Taek; Bai, Hyoung-Woo; Kim, Ung-Jin; Bae, Hyeun-Jong; Gon Wi, Seung; Cho, Jae-Young

    2012-08-01

    Pretreatment of poplar bark with a combination of sulfuric acid (3%, w/w, H2SO4) and gamma irradiation (0-1000 kGy) was performed in an attempt to enhance enzymatic hydrolysis for bioethanol production. The yields of reducing sugar were slightly increased with an increasing irradiation dose, ranging from 35.4% to 51.5%, with a 56.1% reducing sugar yield observed after dilute acid pretreatment. These results clearly showed that soluble sugars were released faster and to a greater extent in dilute acid-pretreated poplar bark than in gamma irradiation-pretreated bark. When combined pretreatment was carried out, a drastic increase in reducing sugar yield (83.1%) was found compared with individual pretreatment, indicating the possibility of increasing the convertibility of poplar bark following combined pretreatment. These findings are likely associated with cellulose crystallinity, lignin modification, and removal of hemicelluloses.

  20. Galbanic acid from Ferula szowitsiana enhanced the antibacterial activity of penicillin G and cephalexin against Staphylococcus aureus.

    Science.gov (United States)

    Shahverdi, Ahmad Reza; Fakhimi, Ali; Zarrini, Gholamreza; Dehghan, Gholamreza; Iranshahi, Mehrdad

    2007-09-01

    In this study the enhancement effect of Ferula szowitsiana roots' acetone extract on the antibacterial activity of penicillin G and cephalexin was evaluated against Staphylococcus aureus. Disk diffusion and broth dilution methods were used to determine the antibacterial activity of these antibiotics in the absence and presence of plant extract and its various fractions separated by TLC plate. The active component of plant extract involved in enhancement of penicillin G's and cephalexin's activities had Rf=0.336 on a TLC plate. The spectral data ((1)H-, (13)C-NMR) of this compound revealed that this compound was 7-[6-(beta-carboxyethyl)-5-isopropylidene-1,2-dimethylcyclo-hexylmethoxy]coumarin (galbanic acid), previously isolated from Ferula assa-foetida. In the presence of sub-inhibitory concentration of galbanic acid (100 microg/ml) the MIC of penicillin G for S. aureus decreased from 64 to 1 (a sixteen four-fold decrease) and for cephalexin from 128 to 1 microg/ml (a one hundred twenty eight-fold decrease). The highest fold decrease in MIC was observed for cephalexin in combination of galbanic acid against test strain. These results signify that the low concentration of galbanic acid (100 microg/ml) potentiates the antimicrobial action of penicillin G and cephalexin suggesting a possible utilization of these compounds in combination therapy against S. aureus.

  1. Enhanced sensing of dopamine in the present of ascorbic acid based on graphene/poly(p-aminobenzoic acid) composite film.

    Science.gov (United States)

    Huang, Ke-Jing; Jing, Qiang-Shan; Wu, Zhi-Wei; Wang, Lan; Wei, Cai-Yun

    2011-11-01

    Graphene/p-aminobenzoic acid composite film modified glassy carbon electrode (Gr/p-ABA/GCE) was first employed for the sensitive determination of dopamine (DA). The electrochemical behavior of DA at the modified electrode was investigated by cyclic voltametry (CV), differential pulse voltametry (DPV) and amperometric curve. The oxidation peak currents of DA increased dramatically at Gr/p-ABA/GCE. The modified electrode was used to electrochemically detect dopamine (DA) in the presence of ascorbic acid (AA). The Gr/p-ABA composite film showed excellent electrocatalytic activity for the oxidation of DA in phosphate buffer solution (pH 6.5). The peak separation between DA and AA was large up to 220 mV. Using DPV technique, the calibration curve for DA determination was obtained in the range of 0.05-10 μM. The detection limit for DA was 20 nM. AA did not interfere with the determination of DA because of the very distinct attractive interaction between DA cations and the negatively Gr/p-ABA composite film. The proposed method exhibited good stability and reproducibility.

  2. Inulin Derivatives Obtained Via Enhanced Microwave Synthesis for Nucleic Acid Based Drug Delivery.

    Science.gov (United States)

    Sardo, Carla; Craparo, Emanuela Fabiola; Fiorica, Calogero; Giammona, Gaetano; Cavallaro, Gennara

    2015-01-01

    A new class of therapeutic agents with a high potential for the treatment of different socially relevant human diseases is represented by Nucleic Acid Based Drugs (NABD), including small interfering RNAs (siRNA), decoy oligodeoxynucleotides (decoy ODN) and antisense oligonucleotides (ASOs). Although NABD can be engineered to be specifically directed against virtually any target, their susceptibility to nuclease degradation and the difficulty of delivery into target tissues severely limit their use in clinical practice and require the development of an appropriate nanostructured delivery system. For delivery of NABD, Inulin (Inu), a natural, water soluble and biocompatible polysaccharide, was derivatized by Spermine (Spm), a flexible molecule with four amine groups that, having pKa values in the range between 8-11, is mainly in the protonated form at pH 7.4. The synthesis of related copolymers (Inu-Spm) was performed by a two step reaction, using a method termed Enhanced Microwave Synthesis (EMS) which has the advantage, compared to conventional microwave reaction, that high amount of energy can be applied to the reaction system, by administering microwave irradiation and simultaneously controlling the temperature in the reaction vessel with cooled air. The synthesized inulin derivatives were characterized by FT-IR spectra and (1)H-NMR. INU-Spm derivatives with a degree of derivatization of about 14 % mol/mol were obtained. These polycations were tested to evaluate their ability to form non covalent complexes with genetic material (polyplexes). Agarose gel retardation assays showed that the obtained copolymers are able to electrostatically interact with DNA duplex to form polyplexes at different c/p weight ratios. Moreover, light scattering studies, performed to analyze size and z-potential of polyplexes, evidenced that copolymers are able to interact with genetic material leading to the formation of nanoscaled systems. In addition, biocompatibility of polyplexes

  3. Enhancement of skin wound healing with decellularized scaffolds loaded with hyaluronic acid and epidermal growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Su, Zhongchun; Ma, Huan; Wu, Zhengzheng [Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, Key Lab for Genetic Medicine of Guangdong Province, Jinan University, Guangzhou 510632 (China); Zeng, Huilan [Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou 510632 (China); Li, Zhizhong [Department of Bone, The First Affiliated Hospital, Jinan University, Guangzhou 510632 (China); Wang, Yuechun; Liu, Gexiu [Department of Physiology, School of Medicine, Jinan University, Guangzhou 510632 (China); Xu, Bin; Lin, Yongliang; Zhang, Peng [Grandhope Biotech Co., Ltd., Building D, #408, Guangzhou International Business Incubator, Guangzhou Science Park, Guangzhou 510663, Guangdong (China); Wei, Xing, E-mail: wei70@hotmail.com [Institute of Biomedicine, National Engineering Research Center of Genetic Medicine, Key Lab for Genetic Medicine of Guangdong Province, Jinan University, Guangzhou 510632 (China)

    2014-11-01

    Current therapy for skin wound healing still relies on skin transplantation. Many studies were done to try to find out ways to replace skin transplantation, but there is still no effective alternative therapy. In this study, decellularized scaffolds were prepared from pig peritoneum by a series of physical and chemical treatments, and scaffolds loaded with hyaluronic acid (HA) and epidermal growth factor (EGF) were tested for their effect on wound healing. MTT assay showed that EGF increased NIH3T3 cell viability and confirmed that EGF used in this study was biologically active in vitro. Scanning electron microscope (SEM) showed that HA stably attached to scaffolds even after soaking in PBS for 48 h. ELISA assay showed that HA increased the adsorption of EGF to scaffolds and sustained the release of EGF from scaffolds. Animal study showed that the wounds covered with scaffolds containing HA and EGF recovered best among all 4 groups and had wound healing rates of 49.86%, 70.94% and 87.41% respectively for days 10, 15 and 20 post-surgery compared to scaffolds alone with wound healing rates of 29.26%, 42.80% and 70.14%. In addition, the wounds covered with scaffolds containing EGF alone were smaller than no EGF scaffolds on days 10, 15 and 20 post-surgery. Hematoxylin–Eosin (HE) staining confirmed these results by showing that on days 10, 15 and 20 post-surgery, the thicker epidermis and dermis layers were observed in the wounds covered with scaffolds containing HA and EGF than scaffolds alone. In addition, the thicker epidermis and dermis layers were also observed in the wounds covered with scaffolds containing EGF than scaffolds alone. Skin appendages were observed on day 20 only in the wound covered with scaffolds containing HA and EGF. These results demonstrate that the scaffolds containing HA and EGF can enhance wound healing. - Highlights: • HA can increase the adsorption of EGF to decellularized scaffolds. • HA can sustain the release of EGF from

  4. Enhanced D-lactic acid production from renewable resources using engineered Lactobacillus plantarum.

    Science.gov (United States)

    Zhang, Yixing; Vadlani, Praveen V; Kumar, Amit; Hardwidge, Philip R; Govind, Revathi; Tanaka, Tsutomu; Kondo, Akihiko

    2016-01-01

    D-lactic acid is used as a monomer in the production of poly-D-lactic acid (PDLA), which is used to form heat-resistant stereocomplex poly-lactic acid. To produce cost-effective D-lactic acid by using all sugars derived from biomass efficiently, xylose-assimilating genes encoding xylose isomerase and xylulokinase were cloned into an L-lactate-deficient strain, Lactobacillus plantarum. The resulting recombinant strain, namely L. plantarum NCIMB 8826 ∆ldhL1-pLEM-xylAB, was able to produce D-lactic acid (at optical purity >99 %) from xylose at a yield of 0.53 g g(-1). Simultaneous utilization of glucose and xylose to produce D-lactic acid was also achieved by this strain, and 47.2 g L(-1) of D-lactic acid was produced from 37.5 g L(-1) glucose and 19.7 g L(-1) xylose. Corn stover and soybean meal extract (SBME) were evaluated as cost-effective medium components for D-lactic acid production. Optimization of medium composition using response surface methodology resulted in 30 % reduction in enzyme loading and 70 % reduction in peptone concentration. In addition, we successfully demonstrated D-lactic acid fermentation from corn stover and SBME in a fed-batch fermentation, which yielded 61.4 g L(-1) D-lactic acid with an overall yield of 0.77 g g(-1). All these approaches are geared to attaining high D-lactic acid production from biomass sugars to produce low-cost, highly thermostable biodegradable plastics.

  5. Enhanced Binding Affinity for an i-Motif DNA Substrate Exhibited by a Protein Containing Nucleobase Amino Acids.

    Science.gov (United States)

    Bai, Xiaoguang; Talukder, Poulami; Daskalova, Sasha M; Roy, Basab; Chen, Shengxi; Li, Zhongxian; Dedkova, Larisa M; Hecht, Sidney M

    2017-03-17

    Several variants of a nucleic acid binding motif (RRM1) of putative transcription factor hnRNP LL containing nucleobase amino acids at specific positions have been prepared and used to study binding affinity for the BCL2 i-motif DNA. Molecular modeling suggested a number of amino acids in RRM1 likely to be involved in interaction with the i-motif DNA, and His24 and Arg26 were chosen for modification based on their potential ability to interact with G14 of the i-motif DNA. Four nucleobase amino acids were introduced into RRM1 at one or both of positions 24 and 26. The introduction of cytosine nucleobase 2 into position 24 of RRM1 increased the affinity of the modified protein for the i-motif DNA, consistent with the possible Watson-Crick interaction of 2 and G14. In comparison, the introduction of uracil nucleobase 3 had a minimal effect on DNA affinity. Two structurally simplified nucleobase analogues (1 and 4) lacking both the N-1 and the 2-oxo substituents were also introduced in lieu of His24. Again, the RRM1 analogue containing 1 exhibited enhanced affinity for the i-motif DNA, while the protein analogue containing 4 bound less tightly to the DNA substrate. Finally, the modified protein containing 1 in lieu of Arg26 also bound to the i-motif DNA more strongly than the wild-type protein, but a protein containing 1 both at positions 24 and 26 bound to the DNA less strongly than wild type. The results support the idea of using nucleobase amino acids as protein constituents for controlling and enhancing DNA-protein interaction. Finally, modification of the i-motif DNA at G14 diminished RRM1-DNA interaction, as well as the ability of nucleobase amino acid 1 to stabilize RRM1-DNA interaction.

  6. All-trans retinoic acid enhances bystander effect of suicide gene therapy in the treatment of breast cancer.

    Science.gov (United States)

    Kong, Heng; Liu, Xia; Yang, Liucheng; Qi, Ke; Zhang, Haoyun; Zhang, Jingwen; Huang, Zonghai; Wang, Hongxian

    2016-03-01

    All-trans retinoic acid (ATRA) has been shown to enhance the expression of connexin 43 (Cx43) and the bystander effect (BSE) in suicide gene therapy. These in turn improve effects of suicide gene therapies for several tumor types. However, whether ATRA can improve BSE remains unclear in suicide gene therapy for breast cancer. In the present study, MCF-7, human breast cancer cells were treated with ATRA in combination with a VEGFP-TK/CD gene suicide system developed by our group. We found that this combination enhances the efficiency of cell killing and apoptosis of breast cancer by strengthening the BSE in vitro. ATRA also promotes gap junction intercellular communication (GJIC) in MCF-7 cells by upregulation of the connexin 43 mRNA and protein in MCF-7 cells. These results indicate that enhancement of GJIC by ATRA in suicide gene system might serve as an attractive and cost-effective strategy of therapy for breast cancer cells.

  7. Optimal Extraction of Gallic Acid from Suaeda glauca Bge. Leaves and Enhanced Efficiency by Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Xin-Hong Wang

    2016-01-01

    Full Text Available The ultrasound-assisted extraction (UAE was initially applied to extract gallic acid from Suaeda glauca Bge. using 70% ethanol as extraction solvent. Temperature, liquid-solid ratio, and extraction time were optimized by response surface methodology (RSM, obtaining maximum levels of gallic acid (6.30 mg·g−1 at 51°C, 19.52 mL·g−1, and 42.68 min, respectively. The obtained model was statistically significant (p<0.0001. The verification experiments at the optimum conditions yielded gallic acid for 6.21 mg·g−1. Subsequently, under optimal conditions, four ionic liquids were used to extract gallic acid from Suaeda glauca Bge. The results indicated that the presence of 1-hexyl-3-methylimidazolium chloride allowed increasing the EE of gallic acid up to 8.90 mg·g−1. This might be interpreted in terms of the molecular interaction between ionic liquid and gallic acid. The use of ionic liquids involves a stronger gallic acid extraction capacity than conventional organic volatile solvents. A promising alternative process is proposed for the extraction of gallic acid of Suaeda glauca Bge.

  8. Enhanced washing durability of hydrophobic coating on cellulose fabric using polycarboxylic acids

    Energy Technology Data Exchange (ETDEWEB)

    Huang Wenqi [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Xing Yanjun, E-mail: yjxing@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Key Laboratory of Science and Technology of Eco-Textile (Donghua University), Ministry of Education, Shanghai 201620 (China); Yu Yunyi [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Shang Songmin [Institute of Textiles and Clothing, The Hong Kong Polytechnic University (Hong Kong); Dai Jinjin [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China)

    2011-02-15

    Nine polycarboxylic acids were used to improve washing durability of hydrophobic cellulose fabric finished by sol-gel method. By simultaneous forming ester-bridge between cellulose and silica layer by ester bond, polycarboxylic acids could anchor silica coating onto cellulose fabric to strengthen the adhesion of organic-inorganic hybrid coating. The wettability of treated fabrics was characterized by water contact angle, spray test and hydrostatic pressure test. The results showed that all investigated polycarboxylic acids could improve the durability. The polycarboxylic acid with proper distance between terminal carboxylic acid groups and number of carboxylic acid groups showed the highest durability. 1,2,3,4-butanetetracarboxylic acid (BTCA) led to the best durability of hydrophobic cellulose fabric with water contact angle of 137.6{sup o} (recovery percentage of 94.2%) after 30 washing times. The effect of BTCA on durability was characterized by scanning electron microscopy. This study demonstrated that the surface treatment using polycarboxylic acids and mixed organosilanes is a promising alternative for achieving durable hydrophobic fabrics.

  9. Caffeic acid production enhancement by engineering a phenylalanine over-producing Escherichia coli strain.

    Science.gov (United States)

    Huang, Qin; Lin, Yuheng; Yan, Yajun

    2013-12-01

    Caffeic acid is a plant-specific phenylpropanoic acid with multiple health-improving effects reported, and its therapeutic derivatives have also been studied throughout the last decade. To meet its market need and achieve high-level production, microbial production of caffeic acid approaches have been developed in metabolically engineered Escherichia coli. In our previous work, we have established the first artificial pathway that realized de novo production of caffeic acid using E. coli endogenous 4-hydroxyphenylacetate 3-hydroxylase (4HP3H). In this work, we exploited the catalytic potential of 4HPA3H in the whole-cell bioconversion study and produced 3.82 g/L (461.12 mg/L/OD) caffeic acid from p-coumaric acid, a direct precursor. We further engineered a phenylalanine over-producer into a tyrosine over-producer and then introduced the artificial pathway. After adjusting the expression strategy and optimizing the inoculants timing, de novo production of caffeic acid reached 766.68 mg/L. Both results from the direct precursor and simple carbon sources represent the highest titers of caffeic acid from microbial production so far.

  10. Acetate accumulation enhances mixed culture fermentation of biomass to lactic acid.

    Science.gov (United States)

    Khor, Way Cern; Roume, Hugo; Coma, Marta; Vervaeren, Han; Rabaey, Korneel

    2016-10-01

    Lactic acid is a high-in-demand chemical, which can be produced through fermentation of lignocellulosic feedstock. However, fermentation of complex substrate produces a mixture of products at efficiencies too low to justify a production process. We hypothesized that the background acetic acid concentration plays a critical role in lactic acid yield; therefore, its retention via selective extraction of lactic acid or its addition would improve overall lactic acid production and eliminate net production of acetic acid. To test this hypothesis, we added 10 g/L of acetate to fermentation broth to investigate its effect on products composition and concentration and bacterial community evolution using several substrate-inoculum combinations. With rumen fluid inoculum, lactate concentrations increased by 80 ± 12 % (cornstarch, p 69 % lactic acid bacteria (LAB), predominantly Lactobacillaceae. Higher acetate concentration promoted a more diverse LAB population, especially on non-inoculated bottles. In subsequent tests, acetate was added in a semi-continuous percolation system with grass as substrate. These tests confirmed our findings producing lactate at concentrations 26 ± 5 % (p lactic acid production from waste biomass to levels more attractive for application.

  11. Enhanced L-(+)-lactic acid production by an adapted strain of Rhizopus oryzae using corncob hydrolysate

    DEFF Research Database (Denmark)

    Bai, Dongmei; Li, S.Z.; Liu, Z.L.

    2008-01-01

    -isomer and a simple nutrition requirement by the fungus. Production of-L-(+)-lactic acid by R. oryzae using xylose has been reported; however, its yield and conversion rate are poor compared with that of using glucose. In this study, we report an adapted R. oryzae strain HZS6 that significantly improved efficiency......Corncob is an economic feedstock and more than 20 million tons of corncobs are produced annually in China. Abundant xylose can be potentially converted from the large amount of hemicellulosic materials in corncobs, which makes the crop residue an attractive alternative substrate for a value......-added production of a variety of bioproducts. Lactic acid can be used as a precursor for poly-lactic acid production. Although current industrial lactic acid is produced by lactic acid bacteria using enriched medium, production by Rhizopus oryzae is preferred due to its exclusive formation of the...

  12. Thermochemical pretreatments for enhancing succinic acid production from industrial hemp (Cannabis sativa L.)

    DEFF Research Database (Denmark)

    Gunnarsson, Ingólfur Bragi; Kuglarz, Mariusz; Karakashev, Dimitar Borisov

    2015-01-01

    The aim of this study was to develop an efficient thermochemical method for treatment of industrial hemp biomass, in order to increase its bioconversion to succinic acid. Industrial hemp was subjected to various thermochemical pretreatments using 0-3% H2SO4, NaOH or H2O2 at 121-180°C prior...... to enzymatic hydrolysis. The influence of the different pretreatments on hydrolysis and succinic acid production by Actinobacillus succinogenes 130Z was investigated in batch mode, using anaerobic bottles and bioreactors. Enzymatic hydrolysis and fermentation of hemp material pretreated with 3% H2O2 resulted...... in the highest overall sugar yield (73.5%), maximum succinic acid titer (21.9gL-1), as well as the highest succinic acid yield (83%). Results obtained clearly demonstrated the impact of different pretreatments on the bioconversion efficiency of industrial hemp into succinic acid....

  13. Thermochemical pretreatments for enhancing succinic acid production from industrial hemp (Cannabis sativa L.).

    Science.gov (United States)

    Gunnarsson, Ingólfur B; Kuglarz, Mariusz; Karakashev, Dimitar; Angelidaki, Irini

    2015-04-01

    The aim of this study was to develop an efficient thermochemical method for treatment of industrial hemp biomass, in order to increase its bioconversion to succinic acid. Industrial hemp was subjected to various thermochemical pretreatments using 0-3% H2SO4, NaOH or H2O2 at 121-180°C prior to enzymatic hydrolysis. The influence of the different pretreatments on hydrolysis and succinic acid production by Actinobacillus succinogenes 130Z was investigated in batch mode, using anaerobic bottles and bioreactors. Enzymatic hydrolysis and fermentation of hemp material pretreated with 3% H2O2 resulted in the highest overall sugar yield (73.5%), maximum succinic acid titer (21.9 g L(-1)), as well as the highest succinic acid yield (83%). Results obtained clearly demonstrated the impact of different pretreatments on the bioconversion efficiency of industrial hemp into succinic acid.

  14. ENHANCED PRODUCTION OF GYMNEMIC ACID USING HR BIOELICITOR EXTRACTED FROM XANTHOMONAS SPP.

    Directory of Open Access Journals (Sweden)

    C.Subathra Devi

    2012-01-01

    Full Text Available Use of Gymnema sylvestre, commonly known as periploca of woods an Indian medicinal woody climber has increased recently due to the pharmaceutical potential of gymnemic acids, found in its leaves. Gymnemic acids have been reported to effect a natural treatment for diabetes. This study developed a novel cell culture system for in vitro growth and production of this species, suggesting a possible technology for large scale production of gymnemic acids. Leaf explants grown in Murashige and Skoog salts supplemented with IAA 1.5mg/l and BA 0.5mg/l gave maximum percentage of callus formation compared to other treatments evaluated. The growth rate and gymnemic acid accumulation in the callus suspension culture was determined. The HR protein from Xanthomonas spp. was used as an elicitor for the production of gymnemic acid. When compared to non-elicited cultures, two fold increase of gymnemic acids yield in elicited cultures was observed. The quantification of gymnemic acid was done using HPLC. The total gynemagenin after 21st day of incubation was 30.2389mg/100ml. This method can be used economically in pilot scale studies.

  15. A comparative study on Cu, Cr and As removal from CCA-treated wood waste by dialytic and electrodialytic processes

    DEFF Research Database (Denmark)

    Velizarova, Emiliya; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2002-01-01

    with the performance of a pure dialytic experiment (without an external power supply) in order to reveal transport of charged particles induced solely by internal electrochemical potential differences in the system. Oxalic acid proved to be a more suitable pre-treatment solution than deionised water for wood chips...

  16. Mechanism for enhanced degradation of clofibric acid in aqueous by catalytic ozonation over MnOx/SBA-15.

    Science.gov (United States)

    Sun, Qiangqiang; Wang, Yu; Li, Laisheng; Bing, Jishuai; Wang, Yingxin; Yan, Huihua

    2015-04-09

    Comparative experiments were conducted to investigate the catalytic ability of MnO(x)/SBA-15 for the ozonation of clofibric acid (CA) and its reaction mechanism. Compared with ozonation alone, the degradation of CA was barely enhanced, while the removal of TOC was significantly improved by catalytic ozonation (O3/MnO(x)/SBA-15). Adsorption of CA and its intermediates by MnO(x)/SBA-15 was proved unimportant in O3/MnO(x)/SBA-15 due to the insignificant adsorption of CA and little TOC variation after ceasing ozone in stopped-flow experiment. The more remarkably inhibition effect of sodium bisulfite (NaHSO3) on the removal of TOC in catalytic ozonation than in ozonation alone elucidated that MnO(x)/SBA-15 facilitated the generation of hydroxyl radicals (OH), which was further verified by electron spin-resonance spectroscopy (ESR). Highly dispersed MnO(x) on SBA-15 were believed to be the main active component in MnO(x)/SBA-15. Some intermediates were indentified and different degradation routes of CA were proposed in both ozonation alone and catalytic ozonation. The amounts of small molecular carboxylic acids (i.e., formic acid (FA), acetic acid (AA) and oxalic acid (OA)) generated in catalytic ozonation were lower than in ozonation alone, resulting from the generation of more OH.

  17. Structural and dynamic changes associated with beneficial engineered single-amino-acid deletion mutations in enhanced green fluorescent protein

    Energy Technology Data Exchange (ETDEWEB)

    Arpino, James A. J. [Cardiff University, Park Place, Cardiff CF10 3AT Wales (United Kingdom); Rizkallah, Pierre J., E-mail: rizkallahp@cardiff.ac.uk [Cardiff University, Heath Park, Cardiff CF14 4XN Wales (United Kingdom); Jones, D. Dafydd, E-mail: rizkallahp@cardiff.ac.uk [Cardiff University, Park Place, Cardiff CF10 3AT Wales (United Kingdom)

    2014-08-01

    The beneficial engineered single-amino-acid deletion variants EGFP{sup D190Δ} and EGFP{sup A227Δ} have been studied. Single-amino-acid deletions are a common part of the natural evolutionary landscape but are rarely sampled during protein engineering owing to limited and prejudiced molecular understanding of mutations that shorten the protein backbone. Single-amino-acid deletion variants of enhanced green fluorescent protein (EGFP) have been identified by directed evolution with the beneficial effect of imparting increased cellular fluorescence. Biophysical characterization revealed that increased functional protein production and not changes to the fluorescence parameters was the mechanism that was likely to be responsible. The structure EGFP{sup D190Δ} containing a deletion within a loop revealed propagated changes only after the deleted residue. The structure of EGFP{sup A227Δ} revealed that a ‘flipping’ mechanism was used to adjust for residue deletion at the end of a β-strand, with amino acids C-terminal to the deletion site repositioning to take the place of the deleted amino acid. In both variants new networks of short-range and long-range interactions are generated while maintaining the integrity of the hydrophobic core. Both deletion variants also displayed significant local and long-range changes in dynamics, as evident by changes in B factors compared with EGFP. Rather than being detrimental, deletion mutations can introduce beneficial structural effects through altering core protein properties, folding and dynamics, as well as function.

  18. Enhanced bio-decolorization of 1-amino-4-bromoanthraquinone-2-sulfonic acid by Sphingomonas xenophaga with nutrient amendment

    Institute of Scientific and Technical Information of China (English)

    Hong Lu; Xiaofan Guan; Jing Wang; Jiti Zhou; Haikun Zhang

    2015-01-01

    Bacterial decolorization of anthraquinone dye intermediates is a slow process under aerobic conditions.To speed up the process,in the present study,effects of various nutrients on 1-amino-4-bromoanthraquinone-2-sulfonic acid (ABAS) decolorization by Sphingomonas xenophaga QYY were investigated.The results showed that peptone,yeast extract and casamino acid amendments promoted ABAS bio-decolorization.In particular,the addition of peptone and casamino acids could improve the decolorization activity of strain QYY.Further experiments showed that L-proline had a more significant accelerating effect on ABAS decolorization compared with other amino acids.L-Proline not only supported cell growth,but also significantly increased the decolorization activity of strain QYY.Membrane proteins of strain QYY exhibited ABAS decolorization activities in the presence of L-proline or reduced nicotinamide adenine dinucleotide,while this behavior was not observed in the presence of other amino acids.Moreover,the positive correlation between L-proline concentration and the decolorization activity of membrane proteins was observed,indicating that L-proline plays an important role in ABAS decolorization.The above findings provide us not only a novel insight into bacterial ABAS decolorization,but also an L-proline-supplemented bioaugmentation strategy for enhancing ABAS bio-decolorization.

  19. Enhanced GLUT4-Dependent Glucose Transport Relieves Nutrient Stress in Obese Mice Through Changes in Lipid and Amino Acid Metabolism.

    Science.gov (United States)

    Gurley, Jami M; Ilkayeva, Olga; Jackson, Robert M; Griesel, Beth A; White, Phillip; Matsuzaki, Satochi; Qaisar, Rizwan; Van Remmen, Holly; Humphries, Kenneth M; Newgard, Christopher B; Olson, Ann Louise

    2016-12-01

    Impaired GLUT4-dependent glucose uptake is a contributing factor in the development of whole-body insulin resistance in obese patients and obese animal models. Previously, we demonstrated that transgenic mice engineered to express the human GLUT4 gene under the control of the human GLUT4 promoter (i.e., transgenic [TG] mice) are resistant to obesity-induced insulin resistance. A likely mechanism underlying increased insulin sensitivity is increased glucose uptake in skeletal muscle. The purpose of this study was to investigate the broader metabolic consequences of enhanced glucose uptake into muscle. We observed that the expression of several nuclear and mitochondrially encoded mitochondrial enzymes was decreased in TG mice but that mitochondrial number, size, and fatty acid respiration rates were unchanged. Interestingly, both pyruvate and glutamate respiration rates were decreased in TG mice. Metabolomics analyses of skeletal muscle samples revealed that increased GLUT4 transgene expression was associated with decreased levels of some tricarboxylic acid intermediates and amino acids, whereas the levels of several glucogenic amino acids were elevated. Furthermore, fasting acyl carnitines in obese TG mice were decreased, indicating that increased GLUT4-dependent glucose flux decreases nutrient stress by altering lipid and amino acid metabolism in skeletal muscle.

  20. Enhanced bioconversion of ethylene glycol to glycolic acid by a newly isolated Burkholderia sp. EG13.

    Science.gov (United States)

    Gao, Xiaoxin; Ma, Zhengfei; Yang, Limin; Ma, Jiangquan

    2014-10-01

    Burkholderia sp. EG13 with high ethylene glycol-oxidizing activity was isolated from soil, which could be used for the synthesis of glycolic acid from the oxidation of ethylene glycol. Using the resting cells of Burkholderia sp. EG13 as biocatalysts, the optimum reaction temperature and pH were 30 °C and 6.0, respectively. After 24 h of biotransformation, the yield of glycolic acid from 200 mM ethylene glycol was 98.8 %. Furthermore, an integrated bioprocess for the production of glycolic acid which involved in situ product removal (ISPR) was investigated. Using fed-batch method with ISPR, a total of 793 mM glycolic acid has been accumulated in the reaction mixture after the 4th feed.

  1. Amino acids assisted hydrothermal synthesis of hierarchically structured ZnO with enhanced photocatalytic activities

    Science.gov (United States)

    Guo, Yanxia; Lin, Siwen; Li, Xuan; Liu, Yuping

    2016-10-01

    Novel hierarchically structured ZnO, including rose-like, dandelion-like and flower-like, have been synthesized through a simple hydrothermal process using different amino acids (glutamine, histidine and glycine) as structure-directing agents and urea as deposition agent, followed by subsequent calcination. Amino acids played a crucial role in the formation of hierarchically structured ZnO, and different amino acids could induce different exquisite shapes and assembly ways, as well as more oxygen defects. The prepared hierarchically structured ZnO exhibited excellent photocatalytic activities for the photodegradation of Rhodamine B, which was associated with their special hierarchical structures, large BET surface area and the existence of more oxygen defects. Amino acid-assisted growth mechanism of hierarchically structured ZnO was also discussed.

  2. The enhancement of reproduction and biodegradation activity of eukaryiotic cells by humic acids.

    Science.gov (United States)

    Siglova, M; Cejkova, A; Masak, J; Jirku, V; Snajdr, J; Valina, O

    2003-01-01

    Fourteen samples of humic acids (HA) were screened for ability to influence reproduction and biodegradation activity of eukaryotic cells in the presence of chosen toxic pollutants. Microorganisms Candida maltosa and Rhodotorula mucilaginosa (soil isolates) were used for all tests. It was observed during our experiments that some samples of humic acids served as a protection against the high concentration of toxic pollutants (phenol, naphtalene etc). This effect can be widely used in many bioremediation technologies.

  3. Enhanced adsorption of humic acids on ordered mesoporous carbon compared with microporous activated carbon.

    Science.gov (United States)

    Liu, Fengling; Xu, Zhaoyi; Wan, Haiqin; Wan, Yuqiu; Zheng, Shourong; Zhu, Dongqiang

    2011-04-01

    Humic acids are ubiquitous in surface and underground waters and may pose potential risk to human health when present in drinking water sources. In this study, ordered mesoporous carbon was synthesized by means of a hard template method and further characterized by X-ray diffraction, N2 adsorption, transition electron microscopy, elemental analysis, and zeta-potential measurement. Batch experiments were conducted to evaluate adsorption of two humic acids from coal and soil, respectively, on the synthesized carbon. For comparison, a commercial microporous activated carbon and nonporous graphite were included as additional adsorbents; moreover, phenol was adopted as a small probe adsorbate. Pore size distribution characterization showed that the synthesized carbon had ordered mesoporous structure, whereas the activated carbon was composed mainly of micropores with a much broader pore size distribution. Accordingly, adsorption of the two humic acids was substantially lower on the activated carbon than on the synthesized carbon, because of the size-exclusion effect. In contrast, the synthesized carbon and activated carbon showed comparable adsorption for phenol when the size-exclusion effect was not in operation. Additionally, we verified by size-exclusion chromatography studies that the synthesized carbon exhibited greater adsorption for the large humic acid fraction than the activated carbon. The pH dependence of adsorption on the three carbonaceous adsorbents was also compared between the two test humic acids. The findings highlight the potential of using ordered mesoporous carbon as a superior adsorbent for the removal of humic acids.

  4. Enhancement of L(+)-Lactic Acid Production of Immobilized Rhizopus Oryzae Implanted by Ion Beams

    Institute of Scientific and Technical Information of China (English)

    FAN Yonghong; YANG Yingge; ZHENG Zhiming; LI Wen; WANG Peng; YAO Liming; YU Zengliang

    2008-01-01

    Immobilized Rhizopus oryzae culturing may be a solution to the inhibited production of L(+)-lactic acid in submerged fermentation, which is caused by aggregated mycelia floc. In the present study, a R. Oryzae mutant (RL6041) with a 90% conversion rate of glucose into L-lactic acid was obtained by N+ implantation under the optimized conditions of a beam energy of 15 keV and a dose of 2.6 × 1015 ions/cm2. Using polyurethane foam as the immobilization matrix, the optimal L-lactic acid production conditions were determined as 4 mm polyurethane foam, 150 r/min, 50 g/L ~ 80 g/L of initial glucose, 38~C and pH 6.0. 15-cycle repeated productions of L-lactic acid by immobilized RL6041 were performed under the optimized culturing conditions and over 80% of the glucose was converted into L-lactic acid in 30 hours on average. The results show that immobilized RL6041 is a promising candidate for continuous L-lactic acid production.

  5. Enhancement of L(+)-Lactic Acid Production of Immobilized Rhizopus Oryzae Implanted by Ion Beams

    Science.gov (United States)

    Fan, Yonghong; Yang, Yingge; Zheng, Zhiming; Li, Wen; Wang, Peng; Yao, Liming; Yu, Zengliang

    2008-02-01

    Immobilized Rhizopus oryzae culturing may be a solution to the inhibited production of L(+)-lactic acid in submerged fermentation, which is caused by aggregated mycelia floc. In the present study, a R. oryzae mutant (RL6041) with a 90% conversion rate of glucose into L-lactic acid was obtained by N+ implantation under the optimized conditions of a beam energy of 15 keV and a dose of 2.6 × 1015 ions/cm2. Using polyurethane foam as the immobilization matrix, the optimal L-lactic acid production conditions were determined as 4 mm polyurethane foam, 150 r/min, 50 g/L ~ 80 g/L of initial glucose, 38°C and pH 6.0. 15-cycle repeated productions of L-lactic acid by immobilized RL6041 were performed under the optimized culturing conditions and over 80% of the glucose was converted into L-lactic acid in 30 hours on average. The results show that immobilized RL6041 is a promising candidate for continuous L-lactic acid production.

  6. Enhanced Bio-hydrogen Production from Protein Wastewater by Altering Protein Structure and Amino Acids Acidification Type

    Science.gov (United States)

    Xiao, Naidong; Chen, Yinguang; Chen, Aihui; Feng, Leiyu

    2014-02-01

    Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control.

  7. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Science.gov (United States)

    Chorna, Nataliya E; Santos-Soto, Iván J; Carballeira, Nestor M; Morales, Joan L; de la Nuez, Janneliz; Cátala-Valentin, Alma; Chornyy, Anatoliy P; Vázquez-Montes, Adrinel; De Ortiz, Sandra Peña

    2013-01-01

    Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN), the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v.) microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  8. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Nataliya E Chorna

    Full Text Available Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN, the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ of the dentate gyrus (DG and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v. microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  9. Promoting extracellular matrix remodeling via ascorbic acid enhances the survival of primary ovarian follicles encapsulated in alginate hydrogels.

    Science.gov (United States)

    Tagler, David; Makanji, Yogeshwar; Tu, Tao; Bernabé, Beatriz Peñalver; Lee, Raymond; Zhu, Jie; Kniazeva, Ekaterina; Hornick, Jessica E; Woodruff, Teresa K; Shea, Lonnie D

    2014-07-01

    The in vitro growth of ovarian follicles is an emerging technology for fertility preservation. Various strategies support the culture of secondary and multilayer follicles from various species including mice, non-human primate, and human; however, the culture of early stage (primary and primordial) follicles, which are more abundant in the ovary and survive cryopreservation, has been limited. Hydrogel-encapsulating follicle culture systems that employed feeder cells, such as mouse embryonic fibroblasts (MEFs), stimulated the growth of primary follicles (70-80 µm); yet, survival was low and smaller follicles (ascorbic acid based on its role in extracellular matrix (ECM) deposition/remodeling for other applications. The selection of ascorbic acid was further supported by a microarray analysis that suggested a decrease in mRNA levels of enzymes within the ascorbate pathway between primordial, primary, and secondary follicles. The supplementation of ascorbic acid (50 µg/mL) significantly enhanced the survival of primary follicles (<80 µm) cultured in alginate hydrogels, which coincided with improved structural integrity. Follicles developed antral cavities and increased to diameters exceeding 250 µm. Consistent with improved structural integrity, the gene/protein expression of ECM and cell adhesion molecules was significantly changed. This research supports the notion that modifying the culture environment (medium components) can substantially enhance the survival and growth of early stage follicles.

  10. Comparison of hot hydroxylamine hydrochloride and oxalic acid leaching of stream sediment and coated rock samples as anomaly enhancement techniques

    Science.gov (United States)

    Filipek, L.H.; Chao, T.T.; Theobald, P.K.

    1982-01-01

    A hot hydroxylamine hydrochloride (H-Hxl) extraction in 25% acetic acid is compared with the commonly used oxalic acid extraction as a method of anomaly enhancement for Cu and Zn in samples from two very different metal deposits and climatic environments. Results obtained on minus-80-mesh stream sediments from an area near the Magruder massive sulfide deposit in Lincoln County, Georgia, where the climate is humid subtropical, indicate that H-Hxl enhances the anomaly for Cu by a factor of 2 and for Zn by a factor of 1.5, compared to the oxalic method. Analyses of Fe oxide-coated rock samples from outcrops overlying the North Silver Bell porphyry copper deposit near Tucson, Arizona, where the climate is semi-arid to arid, indicate that both techniques effectively outline the zones of hydrothermal alteration. The H-Hxl extraction can also perform well in high-carbonate or high-clay environments, where other workers have suggested that oxalic acid is not very effective. Therefore, the H-Hxl method is recommended for general exploration use. ?? 1982.

  11. Surface functionalization of titanium substrates with chitosan-lauric acid conjugate to enhance osteoblasts functions and inhibit bacteria adhesion.

    Science.gov (United States)

    Zhao, Lu; Hu, Yan; Xu, Dawei; Cai, Kaiyong

    2014-07-01

    Orthopedic implants failures are generally related to poor osseointegration and/or bacterial infection in clinical application. Surface functionalization of an implant is one promising alternative for enhancing osseointegration and/or reducing bacterial infection, thus ensuring the long term survival of the implant. In this study, titanium (Ti) substrates were surface functionalized with a polydopamine (PDOP) film as an intermediate layer for post-immobilization of chitosan-lauric acid (Chi-LA) conjugate. Chi-LA conjugate was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR) and hydrogen proton nuclear magnetic resonance (NMR) spectrometer, respectively. Lauric acid (LA), a natural saturated fatty acid, was used mainly due to its good antibacterial property. Scanning electron microscopy (SEM) and water contact angle measurements were employed to detect the morphology changes and surface wettability of Ti substrates. The results suggested that Chi-LA conjugate was successfully immobilized onto the surfaces of Ti substrates. In vitro tests confirmed that the cell adhesion, cell viability, intracellular alkaline phosphatase activity and mineralization capacity of osteoblasts were remarkably improved when cultured onto Chi-LA surface functionalized Ti substrates. Antibacterial assay against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) showed that the Chi-LA modified Ti substrates efficiently inhibited the adhesion and growth of bacteria. Overall, this study developed a promising approach to fabricate functional Ti-based orthopedic implants, which could enhance the biological functions of osteoblasts and concurrently reduce bacteria adhesion.

  12. Citric acid enhances the phytoextraction of manganese and plant growth by alleviating the ultrastructural damages in Juncus effusus L

    Energy Technology Data Exchange (ETDEWEB)

    Najeeb, U.; Xu, L.; Ali, Shafaqat [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Jilani, Ghulam, E-mail: jilani@uaar.edu.pk [Department of Soil Science, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Punjab 46300 (Pakistan); Gong, H.J. [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China); Shen, W.Q. [The University of Nottingham at Ningbo, Ningbo 315100 (China); Zhou, W.J., E-mail: wjzhou@zju.edu.cn [Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)

    2009-10-30

    Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 {mu}M) alone, Mn (500 {mu}M) + citric acid (5 mM), and Mn (500 {mu}M) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed

  13. Enhanced photoluminescence in transparent thin films of polyaniline–zinc oxide nanocomposite prepared from oleic acid modified zinc oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sajimol Augustine, M., E-mail: sajimollazar@gmail.com [Department of Physics, St. Teresa' s College, Kochi-11, Kerala (India); Jeeju, P.P.; Varma, S.J.; Francis Xavier, P.A. [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Kochi-22, Kerala (India); Jayalekshmi, S., E-mail: lakshminathcusat@gmail.com [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Kochi-22, Kerala (India)

    2014-07-01

    Oleic acid capped zinc oxide (ZnO) nanoparticles have been synthesized by a wet chemical route. The chemical oxidative method is employed to synthesize polyaniline (PANI) and PANI/ZnO nanocomposites doped with four different dopants such as orthophosphoric acid (H{sub 3}PO{sub 4}), hydrochloric acid (HCl), naphthalene-2-sulphonic acid and camphor sulphonic acid (CSA). The samples have been structurally characterized by X-ray diffraction (XRD), field emission scanning electron microscopy and Fourier transform infrared (FT-IR) spectroscopic techniques. A comparison of the photoluminescence (PL) emission intensity of PANI and PANI/ZnO nanocomposites is attempted. The enhanced PL intensity in PANI/ZnO nanocomposites is caused by the presence of nanostructured and highly fluorescent ZnO in the composites. It has been observed that, among the composites, the H{sub 3}PO{sub 4} doped PANI/ZnO nanocomposite is found to exhibit the highest PL intensity because of the higher extent of (pi) conjugation and the more orderly arrangement of the benzenoid and quinonoid units. In the present work, transparent thin films of PANI and PANI/ZnO nanocomposite for which PL intensity is found to be maximum, have been prepared after re-doping with CSA by the spin-coating technique. The XRD pattern of the PANI/ZnO film shows exceptionally good crystallanity compared to that of pure PANI, which suggests that the addition of ZnO nanocrystals helps in enhancing the crystallanity of the PANI/ZnO nanocomposite. There is a significant increase in the PL emission intensity of the PANI/ZnO nanocomposite film making it suitable for the fabrication of optoelectronic devices. - Highlights: • Oleic acid capped zinc oxide nanoparticles are synthesized by wet chemical method. • Polyaniline/zinc oxide nanocomposites are prepared by in-situ polymerization. • Polyaniline and polyaniline/zinc oxide thin films are deposited using spin-coating. • Enhanced photoluminescence is observed in polyaniline

  14. Synergistically enhanced selective intracellular uptake of anticancer drug carrier comprising folic acid-conjugated hydrogels containing magnetite nanoparticles

    Science.gov (United States)

    Kim, Haneul; Jo, Ara; Baek, Seulgi; Lim, Daeun; Park, Soon-Yong; Cho, Soo Kyung; Chung, Jin Woong; Yoon, Jinhwan

    2017-01-01

    Targeted drug delivery has long been extensively researched since drug delivery and release at the diseased site with minimum dosage realizes the effective therapy without adverse side effects. In this work, to achieve enhanced intracellular uptake of anticancer drug carriers for efficient chemo-therapy, we have designed targeted multifunctional anticancer drug carrier hydrogels. Temperature-responsive poly(N-isopropylacrylamide) (PNIPAm) hydrogel core containing superparamagnetic magnetite nanoparticles (MNP) were prepared using precipitation polymerization, and further polymerized with amine-functionalized copolymer shell to facilitate the conjugation of targeting ligand. Then, folic acid, specific targeting ligand for cervical cancer cell line (HeLa), was conjugated on the hydrogel surface, yielding the ligand conjugated hybrid hydrogels. We revealed that enhanced intracellular uptake by HeLa cells in vitro was enabled by both magnetic attraction and receptor-mediated endocytosis, which were contributed by MNP and folic acid, respectively. Furthermore, site-specific uptake of the developed carrier was confirmed by incubating with several other cell lines. Based on synergistically enhanced intracellular uptake, efficient cytotoxicity and apoptotic activity of HeLa cells incubated with anticancer drug loaded hybrid hydrogels were successfully achieved. The developed dual-targeted hybrid hydrogels are expected to provide a platform for the next generation intelligent drug delivery systems.

  15. Detoxification of biomass hydrolysates with nucleophilic amino acids enhances alcoholic fermentation.

    Science.gov (United States)

    Xie, Rui; Tu, Maobing; Carvin, Jamarius; Wu, Yonnie

    2015-06-01

    Carbonyl compounds generated in biomass pretreatment hinder the biochemical conversion of biomass hydrolysates to biofuels. A novel approach of detoxifying hydrolysates with amino acids for ethanol production was developed. Among the 20 amino acids assessed for their detoxification efficiency and nucleophilicity, cysteine was the most effective one. It increased both ethanol productivity and final yield of biomass hydrolysates from 0.18 (untreated) to 1.77 g/L/h and from 0.02 to 0.42 g/g, respectively. Detoxification efficiency was followed by histidine and it increased the final yield to 0.42 g/g, then by lysine, tryptophan and asparagine. It was observed all five effective amino acids contained reactive side-chain functional groups, which played important roles in the amino acid detoxification reaction. The study further showed cysteine and glycine detoxifications were temperature and pH dependent. The mechanistic study using mass spectrometry revealed thiazolidine carboxylic acid, a Schiff base, was formed by condensation of aldehyde and cysteine.

  16. Comparative proteomic analysis of engineered Saccharomyces cerevisiae with enhanced free fatty acid accumulation.

    Science.gov (United States)

    Chen, Liwei; Lee, Jaslyn Jie Lin; Zhang, Jianhua; Chen, Wei Ning

    2016-02-01

    The engineered Saccharomyces cerevisiae strain △faa1△faa4 [Acot5s] was demonstrated to accumulate more free fatty acids (FFA) previously. Here, comparative proteomic analysis was performed to get a global overview of metabolic regulation in the strain. Over 500 proteins were identified, and 82 of those proteins were found to change significantly in the engineered strains. Proteins involved in glycolysis, acetate metabolism, fatty acid synthesis, TCA cycle, glyoxylate cycle, the pentose phosphate pathway, respiration, transportation, and stress response were found to be upregulated in △faa1△faa4 [Acot5s] as compared to the wild type. On the other hand, proteins involved in glycerol, ethanol, ergosterol, and cell wall synthesis were downregulated. Taken together with our metabolite analysis, our results showed that the disruption of Faa1 and Faa4 and expression of Acot5s in the engineered strain △faa1△faa4 [Acot5s] not only relieved the feedback inhibition of fatty acyl-CoAs on fatty acid synthesis, but also caused a major metabolic rearrangement. The rearrangement redirected carbon flux toward the pathways which generate the essential substrates and cofactors for fatty acid synthesis, such as acetyl-CoA, ATP, and NADPH. Therefore, our results help shed light on the mechanism for the increased production of fatty acids in the engineered strains, which is useful in providing information for future studies in biofuel production.

  17. Crosslinked and Dyed Chitosan Fiber Presenting Enhanced Acid Resistance and Bioactivities

    Directory of Open Access Journals (Sweden)

    Xiao-Qiong Li

    2016-04-01

    Full Text Available The application of biodegradable chitosan fiber for healthy and hygienic textiles is limited due to its poor acid resistance in wet processing and poor antioxidant activity. In order to prepare chitosan fiber with good acid resistance and high antioxidant activity, chitosan fiber was first crosslinked by a water-soluble aziridine crosslinker, and then dyed with natural lac dye consisting of polyphenolic anthraquinone compounds. The main application conditions and crosslinking mechanism of the aziridine crosslinker, the adsorption mechanism and building-up property of lac dye on the crosslinked fiber, and the effects of crosslinking and dyeing on the antioxidant and antibacterial activities of chitosan fiber were studied. The crosslinked fiber exhibited greatly reduced weight loss in acidic solution, and possessed excellent acid resistance. Lac dye displayed a very high adsorption capability on the crosslinked fiber and a high utilization rate under weakly acidic medium. The Langmuir–Nernst isotherm was the best model to describe the adsorption behavior of lac dye, and Langmuir adsorption had great contribution to total adsorption. Lac dyeing imparted good antioxidant activity to chitosan fiber. Crosslinking and dyeing had no impact on the good inherent antibacterial activity of chitosan fiber.

  18. Fish oil at low dietary levels enhances physiological activity of sesamin to increase hepatic fatty acid oxidation in rats.

    Science.gov (United States)

    Ide, Takashi

    2012-11-01

    We previously demonstrated that a diet containing fish oil at a level of 80 g/kg strongly stimulated the physiological activity of a sesame sesamin preparation containing sesamin and episesamin at equal amounts to increase hepatic fatty acid oxidation. This study was conducted to clarify whether fish oil at lower dietary levels enhances the physiological activity of sesamin to increase hepatic fatty acid oxidation. Rats were fed experimental diets supplemented with 0 or 2 g sesamin/kg, and containing 0, 15 or 30 g fish oil/kg for 15 days. Among rats fed sesamin-free diets, diets containing 15 and 30 g fish oil/kg slightly increased the activity of enzymes involved in hepatic fatty acid oxidation. Sesamin increased these values irrespective of the presence or absence of fish oil in diets; however, the extent of the increase of many parameters was much greater in rats given fish oil-containing diets than in those fed a fish oil-free diet. Diets simultaneously containing sesamin and fish oil increased the gene expression of various peroxisomal fatty acid oxidation enzymes in a synergistic manner; but they were ineffective in causing a synergistic increase in mRNA levels of mitochondrial fatty acid oxidation enzymes. The extent of the synergistic increase in the activity of hepatic fatty acid oxidation enzymes and mRNA levels of the peroxisomal enzymes was indistinguishable between diets containing 15 and 30 g fish oil/kg and appeared comparable to that observed previously with a diet containing 80 g fish oil/kg.

  19. Novel hydrogels of chitosan and poly(vinyl alcohol)-g-glycolic acid copolymer with enhanced rheological properties.

    Science.gov (United States)

    Lejardi, A; Hernández, R; Criado, M; Santos, Jose I; Etxeberria, A; Sarasua, J R; Mijangos, C

    2014-03-15

    Poly(vinyl alcohol) (PVA) has been grafted with glycolic acid (GL), a biodegradable hydroxyl acid to yield modified poly(vinyl alcohol) (PVAGL). The formation of hydrogels at pH = 6.8 and physiological temperature through blending chitosan (CS) and PVAGL at different concentrations has been investigated. FTIR, DOSY NMR and oscillatory rheology measurements have been carried out on CS/PVAGL hydrogels and the results have been compared to those obtained for CS/PVA hydrogels prepared under the same conditions. The experimental results point to an increase in the number of interactions between chitosan and PVAGL in polymer hydrogels prepared with modified PVA. The resulting materials with enhanced elastic properties and thixotropic behavior are potential candidates to be employed as injectable materials for biomedical applications.

  20. High Fat Diet Exposure during Fetal Life Enhances Plasma and Hepatic Omega-6 Fatty Acid Profiles in Fetal Wistar Rats

    Directory of Open Access Journals (Sweden)

    Marlon E. Cerf

    2015-08-01

    Full Text Available Pregnant rats were fed a high fat diet (HFD for the first (HF1, second (HF2, third (HF3 or all three weeks (HFG of gestation. Maintenance on a HFD during specific periods of gestation was hypothesized to alter fetal glycemia, insulinemia, induce insulin resistance; and alter fetal plasma and hepatic fatty acid (FA profiles. At day 20 of gestation, fetal plasma and hepatic FA profiles were determined by gas chromatography; body weight, fasting glycemia, insulinemia and the Homeostasis Model Assessment (HOMA-insulin resistance were also determined. HF3 fetuses were heaviest concomitant with elevated glycemia and insulin resistance (p < 0.05. HFG fetuses had elevated plasma linoleic (18:2 n-6 and arachidonic (20:4 n-6 acid proportions (p < 0.05. In the liver, HF3 fetuses displayed elevated linoleic, eicosatrienoic (20:3 n-6 and arachidonic acid proportions (p < 0.05. HFG fetuses had reduced hepatic docosatrienoic acid (22:5 n-3 proportions (p < 0.05. High fat maintenance during the final week of fetal life enhances hepatic omega-6 FA profiles in fetuses concomitant with hyperglycemia and insulin resistance thereby presenting a metabolically compromised phenotype.

  1. Reduction of phytic acid and enhancement of bioavailable micronutrients in food grains.

    Science.gov (United States)

    Gupta, Raj Kishor; Gangoliya, Shivraj Singh; Singh, Nand Kumar

    2015-02-01

    More than half of the world populations are affected by micronutrient malnutrition and one third of world's population suffers from anemia and zinc deficiency, particularly in developing countries. Iron and zinc deficiencies are the major health problems worldwide. Phytic acid is the major storage form of phosphorous in cereals, legumes, oil seeds and nuts. Phytic acid is known as a food inhibitor which chelates micronutrient and prevents it to be bioavailabe for monogastric animals, including humans, because they lack enzyme phytase in their digestive tract. Several methods have been developed to reduce the phytic acid content in food and improve the nutritional value of cereal which becomes poor due to such antinutrient. These include genetic improvement as well as several pre-treatment methods such as fermentation, soaking, germination and enzymatic treatment of grains with phytase enzyme. Biofortification of staple crops using modern biotechnological techniques can potentially help in alleviating malnutrition in developing countries.

  2. Modeling of electrodialytic and dialytic removal of Cr, Cu and As from CCA-treated wood chips

    DEFF Research Database (Denmark)

    Ribeiro, Alexandra; Rodriguez-Maroto, J.M.; Mateus, Eduardo;

    2007-01-01

    neutralized by addition of nitric acid in the cathode compartment. The anion and cation-exchange membranes are simply represented as ionic filters that preclude the transport of co-ions (the cations and anions respectively) with the exception of H+, which is retarded but considered to pass through the anion...... the concentration gradients of their compounds and the electromigration of their ionic, simple and complex species during the operation. The model also includes the electromigration of the non-contaminant principal ionic species in the system, H+ and OH, proceeding from the electrolysis at the electrodes, Na......-exchange membrane....

  3. AMPKα is critical for enhancing skeletal muscle fatty acid utilization during in vivo exercise in mice

    DEFF Research Database (Denmark)

    Fentz, Joachim; Kjøbsted, Rasmus; Birk, Jesper B.;

    2015-01-01

    The importance of AMPK in regulation of fatty acid (FA) oxidation in skeletal muscle with contraction/exercise is unresolved. Using a mouse model lacking both AMPKα1 and -α2 in skeletal muscle specifically (mdKO), we hypothesized that FA utilization would be impaired in skeletal muscle. AMPKα md......) and FABPpm (plasma membrane fatty acid binding protein) (by ∼17-40%), together with fully abolished TBC1D1 (tre-2/USP6, BUB2, cdc16 domain family member 1) Ser(237) phosphorylation during contraction/exercise in AMPKα mdKO mice, may impair FA transport capacity and FA transport protein translocation...

  4. Multi-walled carbon nanotubes in aqueous phytic acid for enhancing biosensor

    Science.gov (United States)

    Guo, Xiaoyu; Miao, Yun; Ye, Pingping; Wen, Ying; Yang, Haifeng

    2014-04-01

    The poor dispersion of carbon based nanomaterials without strong acid pretreatment in aqueous solution is a fundamental problem, limiting its applications in biology-related fields. A good dispersion of multi-walled carbon nanotubes (MWCNTs) in water was realized by 50 wt.% phytic acid (PA) solution. As an application case, the PA-MWCNTs dispersion in aqueous solution was used for the immobilization of horseradish peroxidase (HRP) and its direct electrochemistry was realized. The constructed biosensor has a sound limit of detection, wide linear range, and high affinity for hydrogen peroxide (H2O2) as well as being free from interference of co-existing electro-active species.

  5. The molecular assembly of the ionic liquid/aliphatic carboxylic acid/aliphatic amine as effective and safety transdermal permeation enhancers.

    Science.gov (United States)

    Kubota, Koji; Shibata, Akira; Yamaguchi, Toshikazu

    2016-04-30

    In spite of numerous advantages, transdermal drug delivery systems are unfeasible for most drugs because of the barrier effect of the stratum corneum. Ionic liquids were recently used to enhance transdermal drug delivery by improving drug solubility. In the present study, safe and effective ionic liquids for transdermal absorption were obtained as salts generated by a neutralization reaction between highly biocompatible aliphatic carboxylic acids (octanoic acid or isostearic acid) and aliphatic amines (diisopropanolamine or triisopropanolamine) (Medrx Co., Ltd., 2009). The mechanism of skin permeability enhancement by ionic liquids was investigated by hydrophilic phenol red and hydrophobic tulobuterol. Further, the skin permeation enhancing effect was remarkably superior in the acid excess state rather than the neutralization state. Infrared absorption spectrum analysis confirmed that ionic liquids/aliphatic carboxylic acid/aliphatic amine are coexisting at all mixing states. In the acid excess state, ionic liquids interact with aliphatic carboxylic acids via hydrogen bonds. Thus, the skin permeation enhancing effect is not caused by the ionic liquid alone. The "liquid salt mixture," referred to as a complex of ingredients coexisting with ionic liquids, forms a molecular assembly incorporating hydrophilic drug. This molecular assembly was considered an effective and safety enhancer of transdermal drug permeation.

  6. Increasing palmitic acid intake enhances milk production and prevents glucose-stimulated fatty acid disappearance without modifying systemic glucose tolerance in mid-lactation dairy cows.

    Science.gov (United States)

    Mathews, A T; Rico, J E; Sprenkle, N T; Lock, A L; McFadden, J W

    2016-11-01

    Feeding saturated fatty acids may enhance milk yield in part by decreasing insulin sensitivity and shifting glucose utilization toward the mammary gland. Our objective was to evaluate the effects of palmitic acid (C16:0) on milk production and insulin sensitivity in cows. Twenty multiparous mid-lactation Holstein cows were enrolled in a study consisting of a 5-d covariate, 49-d treatment, and 14-d posttreatment period. All cows received a common sorghum silage-based diet and were randomly assigned to a diet containing no supplemental fat (control; n=10; 138±45d in milk) or C16:0 at 4% of ration DM (PALM; 98% C16:0; n=10; 136±44d in milk). Blood and milk were collected at routine intervals. Intravenous glucose tolerance tests (300mg/kg of body weight) were performed at d -1, 24, and 49 relative to start of treatment. Data were analyzed as repeated measures using a mixed model with fixed effects of treatment and time, and milk yield served as a covariate. The PALM treatment increased milk yield by wk 7. Furthermore, PALM increased milk fat yield and energy-corrected milk at wk 3 and 7. Changes in milk production occurred in parallel with enhanced energy intake. Increased milk fat yield during PALM treatment was due to increased C16:0 and C16:1 incorporation; PALM had no effect on concentration of milk components, BW, or body condition score. Two weeks posttreatment, energy-corrected milk and milk fat yield remained elevated in PALM-fed cows whereas yields of milk were similar between treatments. Increased milk fat yield after PALM treatment was due to increased de novo lipogenesis and uptake of preformed fatty acids. The basal concentration of nonesterified fatty acids (NEFA) in plasma increased by d 4, 6, and 8 of PALM treatment, a response not observed thereafter. Although PALM supplementation did not modify insulin, glucose, or triacylglycerol levels in plasma, total cholesterol in plasma was elevated by wk 3. Estimated insulin sensitivity was lower during the

  7. Ascorbic acid enhances the accumulation of polycyclic aromatic hydrocarbons (PAHs in roots of tall fescue (Festuca arundinacea Schreb..

    Directory of Open Access Journals (Sweden)

    Yanzheng Gao

    Full Text Available Plant contamination by polycyclic aromatic hydrocarbons (PAHs is crucial to food safety and human health. Enzyme inhibitors are commonly utilized in agriculture to control plant metabolism of organic components. This study revealed that the enzyme inhibitor ascorbic acid (AA significantly reduced the activities of peroxidase (POD and polyphenol oxidase (PPO, thus enhancing the potential risks of PAH contamination in tall fescue (Festuca arundinacea Schreb.. POD and PPO enzymes in vitro effectively decomposed naphthalene (NAP, phenanthrene (PHE and anthracene (ANT. The presence of AA reduced POD and PPO activities in plants, and thus was likely responsible for enhanced PAH accumulation in tall fescue. This conclusion is supported by the significantly enhanced uptake of PHE in plants in the presence of AA, and the positive correlation between enzyme inhibition efficiencies and the rates of metabolism of PHE in tall fescue roots. This study provides a new perspective, that the common application of enzyme inhibitors in agricultural production could increase the accumulation of organic contaminants in plants, hence enhancing risks to food safety and quality.

  8. Bacterial fatty acids enhance recovery from the dauer larva in Caenorhabditis elegans.

    Science.gov (United States)

    Kaul, Tiffany K; Reis Rodrigues, Pedro; Ogungbe, Ifedayo V; Kapahi, Pankaj; Gill, Matthew S

    2014-01-01

    The dauer larva is a specialized dispersal stage in the nematode Caenorhabditis elegans that allows the animal to survive starvation for an extended period of time. The dauer does not feed, but uses chemosensation to identify new food sources and to determine whether to resume reproductive growth. Bacteria produce food signals that promote recovery of the dauer larva, but the chemical identities of these signals remain poorly defined. We find that bacterial fatty acids in the environment augment recovery from the dauer stage under permissive conditions. The effect of increased fatty acids on different dauer constitutive mutants indicates a role for insulin peptide secretion in coordinating recovery from the dauer stage in response to fatty acids. These data suggest that worms can sense the presence of fatty acids in the environment and that elevated levels can promote recovery from dauer arrest. This may be important in the natural environment where the dauer larva needs to determine whether the environment is appropriate to support reproductive growth following dauer exit.

  9. Enhanced Production of Poly-γ-glutamic Acid by Bacillus licheniformis TISTR 1010 with Environmental Controls.

    Science.gov (United States)

    Kongklom, Nuttawut; Shi, Zhongping; Chisti, Yusuf; Sirisansaneeyakul, Sarote

    2016-12-24

    Bacillus licheniformis TISTR 1010 was used for glutamic acid-independent production of poly-γ-glutamic acid (γ-PGA). A fed-batch production strategy was developed involving feedings of glucose, citric acid, and ammonium chloride at specified stages of the fermentation. With the dissolved oxygen concentration controlled at ≥50% of air saturation and the pH controlled at ~7.4, the fed-batch operation at 37 °C afforded a peak γ-PGA concentration of 39.9 ± 0.3 g L(-1) with a productivity of 0.926 ± 0.006 g L(-1) h(-1). The observed productivity was nearly threefold greater than previously reported for glutamic acid-independent production using the strain TISTR 1010. The molecular weight of γ-PGA was in the approximate range of 60 to 135 kDa.

  10. Enhance nisin yield via improving acid-tolerant capability of Lactococcus lactis F44

    Science.gov (United States)

    Zhang, Jian; Caiyin, Qinggele; Feng, Wenjing; Zhao, Xiuli; Qiao, Bin; Zhao, Guangrong; Qiao, Jianjun

    2016-01-01

    Traditionally, nisin was produced industrially by using Lactococcus lactis in the neutral fermentation process. However, nisin showed higher activity in the acidic environment. How to balance the pH value for bacterial normal growth and nisin activity might be the key problem. In this study, 17 acid-tolerant genes and 6 lactic acid synthetic genes were introduced in L. lactis F44, respectively. Comparing to the 2810 IU/mL nisin yield of the original strain F44, the nisin titer of the engineered strains over-expressing hdeAB, ldh and murG, increased to 3850, 3979 and 4377 IU/mL, respectively. These engineered strains showed more stable intracellular pH value during the fermentation process. Improvement of lactate production could partly provide the extra energy for the expression of acid tolerance genes during growth. Co-overexpression of hdeAB, murG, and ldh(Z) in strain F44 resulted in the nisin titer of 4913 IU/mL. The engineered strain (ABGL) could grow on plates with pH 4.2, comparing to the surviving pH 4.6 of strain F44. The fed-batch fermentation showed nisin titer of the co-expression L. lactis strain could reach 5563 IU/mL with lower pH condition and longer cultivation time. This work provides a novel strategy of constructing robust strains for use in industry process. PMID:27306587

  11. Ferulic acid enhances IgE binding to peanut allergens in western blots.

    Science.gov (United States)

    Phenolic compounds at high concentrations are known to form insoluble complexes with proteins. We hypothesized that this complex formation could interfere with Western blot and ELISA assays for peanut allergens. To verify this, three simple phenolic compounds (ferulic, caffeic, and chlorogenic acids...

  12. Surfactant enhanced disinfection of the human norovirus surrogate, tulane virus with organic acids and surfactant

    Science.gov (United States)

    Human infection with foodborne viruses can occur following consumption of contaminated food, person-to-person body contact, or release of aerosols. Combinatorial treatments of surfactants and organic acids may have synergistic or additive mechanisms to inactivate foodborne viruses and prevent outbr...

  13. Feeding strategies for enhanced lactobionic acid production from whey by Pseudomonas taetrolens.

    Science.gov (United States)

    Alonso, Saúl; Rendueles, Manuel; Díaz, Mario

    2013-04-01

    High-level production of lactobionic acid from whey by Pseudomonas taetrolens under fed-batch fermentation was achieved in this study. Different feeding strategies were evaluated according to the physiological status and fermentation performance of P. taetrolens. A lactobionic acid titer of 164 g/L was obtained under co-feeding conditions affording specific and volumetric productivities of 1.4 g/g h and 2.05 g/L h, respectively. Flow cytometry assessment revealed that P. taetrolens cells exhibited a robust physiological status, which makes them particularly well-suited for employing concentrated nutrient solutions to further prolong the growth and production phases. Such detailed knowledge of the physiological status has been revealed to be a key issue to further support the development of high-yield lactobionic acid production processes under feeding strategies. The present study has demonstrated the feasibility of P. taetrolens to achieve high-level bio-production of lactobionic acid from whey through fed-batch cultivation, suggesting its major potential for industrial-scale implementation.

  14. Water Soluble Usnic Acid-Polyacrylamide Complexes with Enhanced Antimicrobial Activity against Staphylococcus epidermidis

    Directory of Open Access Journals (Sweden)

    Iolanda Francolini

    2013-04-01

    Full Text Available Usnic acid, a potent antimicrobial and anticancer agent, poorly soluble in water, was complexed to novel antimicrobial polyacrylamides by establishment of strong acidic-base interactions. Thermal and spectroscopic analysis evidenced a molecular dispersion of the drug in the polymers and a complete drug/polymer miscibility for all the tested compositions. The polymer/drug complexes promptly dissolved in water and possessed a greater antimicrobial activity against Staphylococcus epidermidis than both the free drug and the polymer alone. The best results were obtained with the complex based on the lowest molecular weight polymer and containing a low drug content. Such a complex showed a larger inhibition zone of bacterial growth and a lower minimum inhibitory concentration (MIC with respect to usnic acid alone. This improved killing effect is presumably due to the reduced size of the complexes that allows an efficient cellular uptake of the antimicrobial complexes. The killing effect extent seems to be not significantly dependent on usnic acid content in the samples.

  15. Nitric Acid-Treated Carbon Fibers with Enhanced Hydrophilicity for Candida tropicalis Immobilization in Xylitol Fermentation

    Directory of Open Access Journals (Sweden)

    Le Wang

    2016-03-01

    Full Text Available Nitric acid (HNO3-treated carbon fiber (CF rich in hydrophilic groups was applied as a cell-immobilized carrier for xylitol fermentation. Using scanning electron microscopy, we characterized the morphology of the HNO3-treated CF. Additionally, we evaluated the immobilized efficiency (IE of Candida tropicalis and xylitol fermentation yield by investigating the surface properties of nitric acid treated CF, specifically, the acidic group content, zero charge point, degree of moisture and contact angle. We found that adhesion is the major mechanism for cell immobilization and that it is greatly affected by the hydrophilic–hydrophilic surface properties. In our experiments, we found 3 hto be the optimal time for treating CF with nitric acid, resulting in an improved IE of Candida tropicalis of 0.98 g∙g−1 and the highest xylitol yield and volumetric productivity (70.13% and 1.22 g∙L−1∙h−1, respectively. The HNO3-treated CF represents a promising method for preparing biocompatible biocarriers for multi-batch fermentation.

  16. Omega-3 Polyunsaturated Fatty Acids Enhance Neuronal Differentiation in Cultured Rat Neural Stem Cells

    Directory of Open Access Journals (Sweden)

    Masanori Katakura

    2013-01-01

    Full Text Available Polyunsaturated fatty acids (PUFAs can induce neurogenesis and recovery from brain diseases. However, the exact mechanisms of the beneficial effects of PUFAs have not been conclusively described. We recently reported that docosahexaenoic acid (DHA induced neuronal differentiation by decreasing Hes1 expression and increasing p27kip1 expression, which causes cell cycle arrest in neural stem cells (NSCs. In the present study, we examined the effect of eicosapentaenoic acid (EPA and arachidonic acid (AA on differentiation, expression of basic helix-loop-helix transcription factors (Hes1, Hes6, and NeuroD, and the cell cycle of cultured NSCs. EPA also increased mRNA levels of Hes1, an inhibitor of neuronal differentiation, Hes6, an inhibitor of Hes1, NeuroD, and Map2 mRNA and Tuj-1-positive cells (a neuronal marker, indicating that EPA induced neuronal differentiation. EPA increased the mRNA levels of p21cip1 and p27kip1, a cyclin-dependent kinase inhibitor, which indicated that EPA induced cell cycle arrest. Treatment with AA decreased Hes1 mRNA but did not affect NeuroD and Map2 mRNA levels. Furthermore, AA did not affect the number of Tuj-1-positive cells or cell cycle progression. These results indicated that EPA could be involved in neuronal differentiation by mechanisms alternative to those of DHA, whereas AA did not affect neuronal differentiation in NSCs.

  17. Activation of peroxisome proliferator-activated receptor-{alpha} enhances fatty acid oxidation in human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kawada, Teruo, E-mail: fat@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2011-04-22

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. {yields} PPAR{alpha} activation also increased insulin-dependent glucose uptake in human adipocytes. {yields} PPAR{alpha} activation did not affect lipid accumulation in human adipocytes. {yields} PPAR{alpha} activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPAR{alpha} in adipocytes have been unclarified. We examined the functions of PPAR{alpha} using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPAR{alpha} by GW7647, a potent PPAR{alpha} agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPAR{gamma}, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPAR{alpha} activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPAR{gamma} is activated. On the other hand, PPAR{alpha} activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPAR{alpha}-dependent manner. Moreover, PPAR{alpha} activation increased the production of CO{sub 2} and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPAR{alpha} stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPAR{alpha} agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected

  18. Differential stimulation of luminol-enhanced chemiluminescence (CL) and arachidonic acid metabolism in rat peritoneal neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, R.J.; Adams, L.M.; Cullinan, C.A.; Berkenkopf, J.W.; Weichman, B.M.

    1986-03-05

    Phorbol 12-myristate, 13-acetate (PMA) induced the production of radical oxygen species (ROS) from rat peritoneal neutrophils as assessed by CL. ROS generation occurred in a time- (maximum at 13.5 min) and dose- (concentration range of 1.7-498 nM) related fashion. However, 166 nM PMA did not induce either cyclooxygenase (CO) or lipoxygenase (LPO) product formation by 20 min post-stimulation. Conversely, A23187, at concentrations between 0.1 and 10 ..mu..M, stimulated both pathways of arachidonic acid metabolism, but had little or no effect upon ROS production. When suboptimal concentrations of PMA (5.5 nM) and A23187 (0.1-1 ..mu..M) were coincubated with the neutrophils, a synergistic ROS response was elicited. However, arachidonic acid metabolism in the presence of PMA was unchanged relative to A12187 alone. Nordihydroguaiaretic acid (NDGA) inhibited both PMA-induced CL (IC/sub 50/ = 0.9 ..mu..M) and A23187-induced arachidonic acid metabolism (IC/sub 50/ = 1.7 ..mu..M and 6.0 ..mu..M for LPO and CO, respectively). The mixed LPO-CO inhibitor, BW755C, behaved in a qualitatively similar manner to NDGA, whereas the CO inhibitors, indomethacin, piroxicam and naproxen had no inhibitory effect on ROS generation at concentrations as high as 100 ..mu..M. These results suggest that NDGA and BW755C may inhibit CL and arachidonic acid metabolism by distinct mechanisms in rat neutrophils.

  19. Preoperative Estimation of Future Remnant Liver Function Following Portal Vein Embolization Using Relative Enhancement on Gadoxetic Acid Disodium-Enhanced Magnetic Resonance Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yozo [Department of Radiology, Aichi Medical University, Aichi 480-1195 (Japan); Department of Diagnostic and Interventional Radiology, Aichi Cancer Center Hospital, Nagoya 464-8681 (Japan); Matsushima, Shigeru; Inaba, Yoshitaka [Department of Diagnostic and Interventional Radiology, Aichi Cancer Center Hospital, Nagoya 464-8681 (Japan); Sano, Tsuyoshi [Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya 464-8681 (Japan); Yamaura, Hidekazu; Kato, Mina [Department of Diagnostic and Interventional Radiology, Aichi Cancer Center Hospital, Nagoya 464-8681 (Japan); Shimizu, Yasuhiro; Senda, Yoshiki [Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya 464-8681 (Japan); Ishiguchi, Tsuneo [Department of Radiology, Aichi Medical University, Aichi 480-1195 (Japan)

    2015-11-01

    To retrospectively evaluate relative enhancement (RE) in the hepatobiliary phase of gadoxetic acid disodium-enhanced magnetic resonance (MR) imaging as a preoperative estimation of future remnant liver (FRL) function in a patients who underwent portal vein embolization (PVE). In 53 patients, the correlation between the indocyanine green clearance (ICG-K) and RE imaging was analyzed before hepatectomy (first analysis). Twenty-three of the 53 patients underwent PVE followed by a repeat RE imaging and ICG test before an extended hepatectomy and their results were further analyzed (second analysis). Whole liver function and FRL function were calculated on the MR imaging as follows: RE x total liver volume (RE Index) and FRL-RE x FRL volume (Rem RE Index), respectively. Regarding clinical outcome, posthepatectomy liver failure (PHLF) was evaluated in patients undergoing PVE. Indocyanine green clearance correlated with the RE Index (r = 0.365, p = 0.007), and ICG-K of FRL (ICG-Krem) strongly correlated with the Rem RE Index (r = 0.738, p < 0.001) in the first analysis. Both the ICG-Krem and the Rem RE Index were significantly correlated after PVE (r = 0.508, p = 0.013) at the second analysis. The rate of improvement of the Rem RE Index from before PVE to after PVE was significantly higher than that of ICG-Krem (p = 0.014). Patients with PHLF had a significantly lower Rem RE Index than patients without PHLF (p = 0.023). Relative enhancement imaging can be used to estimate FRL function after PVE.

  20. Arbuscular mycorrhiza increase artemisinin accumulation in Artemisia annua by higher expression of key biosynthesis genes via enhanced jasmonic acid levels.

    Science.gov (United States)

    Mandal, Shantanu; Upadhyay, Shivangi; Wajid, Saima; Ram, Mauji; Jain, Dharam Chand; Singh, Ved Pal; Abdin, Malik Zainul; Kapoor, Rupam

    2015-07-01

    It is becoming increasingly evident that the formation of arbuscular mycorrhiza (AM) enhances secondary metabolite production in shoots. Despite mounting evidence, relatively little is known about the underlying mechanisms. This study suggests that increase in artemisinin concentration in Artemisia annua colonized by Rhizophagus intraradices is due to altered trichome density as well as transcriptional patterns that are mediated via enhanced jasmonic acid (JA) levels. Mycorrhizal (M) plants had higher JA levels in leaf tissue that may be due to induction of an allene oxidase synthase gene (AOS), encoding one of the key enzymes for JA production. Non-mycorrhizal (NM) plants were exogenously supplied with a range of methyl jasmonic acid concentrations. When leaves of NM and M plants with similar levels of endogenous JA were compared, these matched closely in terms of shoot trichome density, artemisinin concentration, and transcript profile of artemisinin biosynthesis genes. Mycorrhization increased artemisinin levels by increasing glandular trichome density and transcriptional activation of artemisinin biosynthesis genes. Transcriptional analysis of some rate-limiting enzymes of mevalonate and methyl erythritol phosphate (MEP) pathways revealed that AM increases isoprenoids by induction of the MEP pathway. A decline in artemisinin concentration in shoots of NM and M plants treated with ibuprofen (an inhibitor of JA biosynthesis) further confirmed the implication of JA in the mechanism of artemisinin production.

  1. Hepatocellular carcinoma: clinical significance of signal heterogeneity in the hepatobiliary phase of gadoxetic acid-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Nobuhiro; Nishie, Akihiro; Asayama, Yoshiki; Ushijima, Yasuhiro; Moirta, Koichiro; Honda, Hiroshi [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences, Fukuoka (Japan); Kubo, Yuichiro; Aishima, Shinichi [Kyushu University, Department of Anatomic Pathology, Graduate School of Medical Sciences, Fukuoka (Japan); Takayama, Yukihisa [Kyushu University, Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Fukuoka (Japan); Shirabe, Ken [Kyushu University, Department of Surgery and Science, Graduate School of Medical Sciences, Fukuoka (Japan)

    2015-01-15

    To clarify the relationship between the biological behaviour of hepatocellular carcinomas (HCCs) and their signal intensity in the hepatobiliary phase of gadoxetic acid-enhanced MR imaging with a special focus on the signal heterogeneity. A total of 68 patients with 70 pathologically proven HCCs were enrolled. On the basis of the signal intensity in the hepatobiliary phase, the lesions were classified into three groups: group 1, homogeneous hypointensity (n = 44); group 2, heterogeneous hyperintensity (n = 20); and group 3, homogeneous hyperintensity (n = 6). The clinicopathological findings were compared among the three groups. The tumour size and the serum level of protein induced by vitamin K absence or antagonist-II (PIVKA-II) were significantly higher in group 2 compared to group 1 (p = 0.0155, p = 0.0215, respectively) and compared to group 3 (p = 0.0330, p = 0.0220, respectively). The organic anion transporting polypeptide 8 (OATP8) expression in group 2 and group 3 was significantly higher than in group 1 (p < 0.0001, p < 0.0001, respectively). Group 2 showed a significantly lower disease-free survival rate compared to group 1 (p = 0.0125), and group 2 was an independent prognostic factor for disease-free survival (p = 0.0308). HCCs in the hepatobiliary phase that are heterogeneously hyperintense on gadoxetic acid-enhanced MR imaging have more malignant potential than other types of HCCs. (orig.)

  2. Transgenic tomato plants overexpressing tyramine N-hydroxycinnamoyltransferase exhibit elevated hydroxycinnamic acid amide levels and enhanced resistance to Pseudomonas syringae.

    Science.gov (United States)

    Campos, Laura; Lisón, Purificación; López-Gresa, María Pilar; Rodrigo, Ismael; Zacarés, Laura; Conejero, Vicente; Bellés, José María

    2014-10-01

    Hydroxycinnamic acid amides (HCAA) are secondary metabolites involved in plant development and defense that have been widely reported throughout the plant kingdom. These phenolics show antioxidant, antiviral, antibacterial, and antifungal activities. Hydroxycinnamoyl-CoA:tyramine N-hydroxycinnamoyl transferase (THT) is the key enzyme in HCAA synthesis and is induced in response to pathogen infection, wounding, or elicitor treatments, preceding HCAA accumulation. We have engineered transgenic tomato plants overexpressing tomato THT. These plants displayed an enhanced THT gene expression in leaves as compared with wild type (WT) plants. Consequently, leaves of THT-overexpressing plants showed a higher constitutive accumulation of the amide coumaroyltyramine (CT). Similar results were found in flowers and fruits. Moreover, feruloyltyramine (FT) also accumulated in these tissues, being present at higher levels in transgenic plants. Accumulation of CT, FT and octopamine, and noradrenaline HCAA in response to Pseudomonas syringae pv. tomato infection was higher in transgenic plants than in the WT plants. Transgenic plants showed an enhanced resistance to the bacterial infection. In addition, this HCAA accumulation was accompanied by an increase in salicylic acid levels and pathogenesis-related gene induction. Taken together, these results suggest that HCAA may play an important role in the defense of tomato plants against P. syringae infection.

  3. Selection of tropical lactic acid bacteria for enhancing the quality of maize silage.

    Science.gov (United States)

    Santos, A O; Ávila, C L S; Schwan, R F

    2013-01-01

    The objective of this study was to select lactic acid bacteria (LAB) strains isolated from silage and assess their effect on the quality of maize silage. The LAB strains were inoculated into aqueous extract obtained from maize to evaluate their production of metabolites and pH reduction. The ability to inhibit the pathogenic and silage-spoilage microorganisms' growth was evaluated. Nine LAB strains that showed the best results were assessed in polyvinyl chloride experimental silos. The inoculation of the LAB strains influenced the concentration of lactic and acetic acids and the diversity of Listeria. The inoculation of silages with Lactobacillus buchneri (UFLA SLM11 and UFLA SLM103 strains) resulted in silages with greater LAB populations and improvements after aerobic exposure. The UFLA SLM11 and SLM103 strains identified as L. buchneri showed to be promising in the treatment of maize silage.

  4. Enhanced removal of Hg(II) from acidic aqueous solution using thiol-functionalized biomass.

    Science.gov (United States)

    Chai, Liyuan; Wang, Qingwei; Li, Qingzhu; Yang, Zhihui; Wang, Yunyan

    2010-01-01

    Spent grain, the low-cost and abundant biomass produced in the brewing industry, was functionalized with thiol groups to be used as an adsorbent for Hg(II) removal from acidic aqueous solution. The adsorbents were characterized by the energy-dispersive X-ray analysis (EDAX) and Fourier transform infrared (FTIR) spectroscopy. Optimum pH for Hg(II) adsorption onto the thiol-functionalized spent grain (TFSG) was 2.0. The equilibrium and kinetics of the adsorption of Hg(II) onto TFSG from acidic aqueous solution were investigated. From the Langmuir isotherm model the maximum adsorption capacity of TFSG for Hg(II) was found to be 221.73 mg g(-1), which was higher than that of most various adsorbents reported in literature. Moreover, the adsorption of Hg(II) onto TFSG followed pseudo-second-order kinetic model.

  5. Crassulacean acid metabolism enhances underwater photosynthesis and diminishes photorespiration in the aquatic plant Isoetes australis

    DEFF Research Database (Denmark)

    Pedersen, Ole; Rich, S.M.; Pulido Pérez, Cristina

    2011-01-01

    Underwater photosynthesis by aquatic plants is often limited by low availability of CO2, and photorespiration can be high. Some aquatic plants utilize crassulacean acid metabolism (CAM) photosynthesis. The benefits of CAM for increased underwater photosynthesis and suppression of photorespiration...... were evaluated for Isoetes australis, a submerged plant that inhabits shallow temporary rock pools. • Leaves high or low in malate were evaluated for underwater net photosynthesis and apparent photorespiration at a range of CO2 and O2 concentrations. • CAM activity was indicated by 9.7-fold higher leaf...... malate at dawn, compared with at dusk, and also by changes in the titratable acidity (lmol H+ equivalents) of leaves. Leaves high in malate showed not only higher underwater net photosynthesis at low external CO2 concentrations but also lower apparent photorespiration. Suppression by CAM of apparent...

  6. Increasing cellular level of phosphatidic acid enhances FGF-1 production in long term-cultured rat astrocytes.

    Science.gov (United States)

    Nagayasu, Yuko; Morita, Shin-Ya; Hayashi, Hideki; Miura, Yutaka; Yokoyama, Kazuki; Michikawa, Makoto; Ito, Jin-Ichi

    2014-05-14

    We found in a previous study that both mRNA expression and release of fibroblast growth factor 1 (FGF-1) are greater in rat astrocytes that are long term-cultured for one month (W/M cells) than in the cells cultured for one week (W/W cells). However, FGF-1 does not enhance phosphorylation of Akt, MEK, and ERK in W/M cells, while it does in W/W cells. In this work we studied the mechanism to cause these differences between W/W and W/M cells in culture. As it is known that long term culture generates oxidative stress, we characterized the stresses which W/M cells undergo in comparison with W/W cells. The levels of superoxide dismutase 1 (SOD1) and mitochondrial Bax were higher in W/M cells than in W/W cells. W/M cells recovered their ability to respond to FGF-1 to enhance phosphorylation of Akt, MEK, and ERK in the presence of antioxidants. Oxidative stress induced by hydrogen peroxide (H2O2) had no effect on mRNA expression of FGF-1 in W/W cells, although H2O2 enhances release of FGF-1 from W/W cells without inducing apoptosis. The influence of cell density was studied on mRNA expression of FGF-1 and cellular response to FGF-1, as an increasing cell density is observed in W/M cells. The increasing cell density enhanced mRNA expression of FGF-1 in W/W cells without suppression of responses to FGF-1. The decrease in cell density lowered the FGF-1 mRNA expression in W/M cells without recovery of the response to FGF-1 to enhance phosphorylation of Akt, MEK, and ERK. These findings suggest that oxidative stress attenuate sensitivity to FGF-1 and higher cell density may enhance FGF-1 expression in W/M cells. In addition, we found that the cellular level of phosphatidic acid (PA) increased in H2O2-treated W/W and W/M cells and decreased by the treatment with antioxidants, and that PA enhances the mRNA expression of FGF-1 in the W/W cells. These findings suggest that the increasing PA production may enhance FGF-1 expression to protect astrocytes against oxidative stress

  7. Alkyl hydroperoxide reductase enhances the growth of Leuconostoc mesenteroides lactic acid bacteria at low temperatures

    OpenAIRE

    Goto, Seitaro; Kawamoto, Jun; Sato, Satoshi B; Iki, Takashi; WATANABE, Itaru; Kudo, Kazuyuki; Esaki, Nobuyoshi; Kurihara, Tatsuo

    2015-01-01

    Lactic acid bacteria (LAB) can cause deterioration of food quality even at low temperatures. In this study, we investigated the cold-adaptation mechanism of a novel food spoilage LAB, Leuconostoc mesenteroides NH04 (NH04). L. mesenteroides was isolated from several spoiled cooked meat products at a high frequency in our factories. NH04 grew rapidly at low temperatures within the shelf-life period and resulted in heavy financial losses. NH04 grew more rapidly than related strains such as Leuco...

  8. Enhanced cellular delivery of cell-penetrating peptide-peptide nucleic acid conjugates by photochemical internalization

    DEFF Research Database (Denmark)

    Shiraishi, Takehiko; Nielsen, Peter E

    2011-01-01

    )) or tetraphenylporphyrin tetrasulfonic acid (TPPS). Cellular uptake of the PNA conjugates were evaluated by using a sensitive cellular method with HeLa pLuc705 cells based on the splicing correction of luciferase gene by targeting antisense oligonucleotides to a cryptic splice site of the mutated luciferase gene....... The cellular efficacy of CPP conjugates were evaluated by measuring luciferase activity as a result of splicing correction and was also confirmed by RT-PCR analysis of luciferase pre-mRNA....

  9. Biliary peritonitis after radiofrequency ablation diagnosed by gadoxetic acid-enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Akihiro; Isoda, Hiroyoshi; Togashi, Kaori [Dept. of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto (Japan); Koyama, Takashi; Todo, Giro; Osaki, Yukio [Osaka Red Cross Hospital, Osaka (Japan)

    2013-12-15

    This study describes the first case of biliary peritonitis after radiofrequency ablation diagnosed by magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA), a hepatocyte-specific MR imaging contrast agent. The image acquired 300 minutes after the administration of Gd-EOB-DTPA was useful to make a definite diagnosis and to identify the pathway of bile leakage. It is important to decide on the acquisition timing with consideration of the predicted location of bile duct injury.

  10. Enhanced polyunsaturated fatty acids production in Mortierella alpina by SSF and the enrichment in chicken breasts

    Directory of Open Access Journals (Sweden)

    Shengli Yang

    2016-10-01

    Full Text Available Background: Distiller's dried grains with solubles (DDGS and soybean meal were used as the substrates for the production of polyunsaturated fatty acids (PUFA in solid-state fermentation (SSF by Mortierella alpine. These fermented products were fed to laying hens. PUFA enrichment from chicken breasts was studied. Methods: The maximum productivity of PUFA was achieved under optimized process condition, including 1% w/w yeast extract as additive, an incubation period of 5 days at 12°C, 10% v/w inoculum level, 75% moisture content, and pH 6.0. The hens were then fed with ration containing soybean DDGS, rapeseed oil, soybean oil, and peanut oil. The control group was fed with basal ration. Results: Under the optimal condition, M. alpine produced total fatty acids (TFA of 182.34 mg/g dry substrate. It has better mycelial growth when soybean meal was added to DDGS (SDDGS. PUFA in fermentation product increased with higher soybean meal content. The addition of 70% soybean meal to DDGS substrate yielded 175.16 mg of TFA, including 2.49 mg eicosapentaenoic acid (EPA and 5.26 mg docosahexaenoic acid (DHA. The ratios of ω-6/ω-3 found in chicken breasts fat were all lower than that found in control by 36.98, 31.51, 18.15, and 12.63% for SDDGS, rapeseed oil, soybean oil, and peanut oil, respectively. Conclusions: This study identified an optimized SSF process to maximize PUFA productivity by M. alpine as the strain. This PUFA-enriched feed increased the PUFA contents as well as the proportions of ω-6 and ω-3 in chicken breasts and liver.

  11. Biliary peritonitis after radiofrequency ablation diagnosed by gadoxetic acid-enhanced MR imaging.

    Science.gov (United States)

    Furuta, Akihiro; Isoda, Hiroyoshi; Koyama, Takashi; Todo, Giro; Osaki, Yukio; Togashi, Kaori

    2013-01-01

    This study describes the first case of biliary peritonitis after radiofrequency ablation diagnosed by magnetic resonance (MR) imaging with gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA), a hepatocyte-specific MR imaging contrast agent. The image acquired 300 minutes after the administration of Gd-EOB-DTPA was useful to make a definite diagnosis and to identify the pathway of bile leakage. It is important to decide on the acquisition timing with consideration of the predicted location of bile duct injury.

  12. Adaptation of Clostridium tyrobutyricum for enhanced tolerance to butyric acid in a fibrous-bed bioreactor.

    Science.gov (United States)

    Zhu, Ying; Yang, Shang-Tian

    2003-01-01

    By immobilization in a fibrous-bed bioreactor (FBB), we succeeded in adapting and selecting an acid-tolerant strain of Clostridium tyrobutyricum that can produce high concentrations of butyrate from glucose and xylose. This mutant grew well under high butyrate concentrations (>30 g/L) and had better fermentative ability as compared to the wild-type strain used to seed the bioreactor. Kinetic analysis of butyrate inhibition on cell growth, acid-forming enzymes, and ATPase activity showed that the adapted cells from the FBB are physiologically different from the original wild type. Compared to the wild type, the adapted culture's maximum specific growth rate increased by 2.3-fold and its growth tolerance to butyrate inhibition increased by 29-fold. The key enzymes in the butyrate-forming pathway, phosphotransbutyrylase (PTB) and butyrate kinase (BK), were also more active in the mutant, with 175% higher PTB and 146% higher BK activities. Also, the mutant's ATPase was less sensitive to inhibition by butyric acid, as indicated by a 4-fold increase in the inhibition rate constant, and was more resistant to the enzyme inhibitor N,N'-dicyclohexylcarbodiimide (DCCD). The lower ATPase sensitivity to butyrate inhibition might have contributed to the increased growth tolerance to butyrate inhibition, which also might be attributed to the higher percentage of saturated fatty acids in the membrane phospholipids (74% in the mutant vs 69% in the wild type). This study shows that cell immobilization in the FBB provides an effective means for in-process adaptation and selection of mutant with higher tolerance to inhibitory fermentation product.

  13. Endohyphal Bacterium Enhances Production of Indole-3-Acetic Acid by a Foliar Fungal Endophyte

    OpenAIRE

    Hoffman, Michele T.; Gunatilaka, Malkanthi K.; Kithsiri Wijeratne; Leslie Gunatilaka; A Elizabeth Arnold

    2013-01-01

    Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have ...

  14. SlMAPK3 enhances tolerance to tomato yellow leaf curl virus (TYLCV) by regulating salicylic acid and jasmonic acid signaling in tomato (Solanum lycopersicum)

    Science.gov (United States)

    Li, Yunzhou; Qin, Lei; Zhao, Jingjing; Muhammad, Tayeb; Cao, Hehe; Li, Hailiang; Zhang, Yan; Liang, Yan

    2017-01-01

    Several recent studies have reported on the role of mitogen-activated protein kinase (MAPK3) in plant immune responses. However, little is known about how MAPK3 functions in tomato (Solanum lycopersicum L.) infected with tomato yellow leaf curl virus (TYLCV). There is also uncertainty about the connection between plant MAPK3 and the salicylic acid (SA) and jasmonic acid (JA) defense-signaling pathways. The results of this study indicated that SlMAPK3 participates in the antiviral response against TYLCV. Tomato seedlings were inoculated with TYLCV to investigate the possible roles of SlMAPK1, SlMAPK2, and SlMAPK3 against this virus. Inoculation with TYLCV strongly induced the expression and the activity of all three genes. Silencing of SlMAPK1, SlMAPK2, and SlMAPK3 reduced tolerance to TYLCV, increased leaf H2O2 concentrations, and attenuated expression of defense-related genes after TYLCV infection, especially in SlMAPK3-silenced plants. Exogenous SA and methyl jasmonic acid (MeJA) both significantly induced SlMAPK3 expression in tomato leaves. Over-expression of SlMAPK3 increased the transcript levels of SA/JA-mediated defense-related genes (PR1, PR1b/SlLapA, SlPI-I, and SlPI-II) and enhanced tolerance to TYLCV. After TYLCV inoculation, the leaves of SlMAPK3 over-expressed plants compared with wild type plants showed less H2O2 accumulation and greater superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity. Overall, the results suggested that SlMAPK3 participates in the antiviral response of tomato to TYLCV, and that this process may be through either the SA or JA defense-signaling pathways. PMID:28222174

  15. Antisense-Mediated Depletion of Tomato Chloroplast Omega-3 Fatty Acid Desaturase Enhances Thermal Tolerance

    Institute of Scientific and Technical Information of China (English)

    Xun-Yan Liu; Jing-Hua Yang; Bin Li; Xiu-Mei Yang; Qing-Wei Meng

    2006-01-01

    A chloroplast-localized tomato (Lycopersicon esculentum Mill.) ω-3 fatty acid desaturase gene (LeFAD7) was isolated and characterized with regard to its sequence, response to various temperatures, and function in antisense transgenic tomato plants. The deduced amino acid sequence had four histidine-rich regions, of which three regions were highly conserved throughout the whole ω-3 fatty acid desaturase gene family.Southern blotting analysis showed that LeFAD7was encoded by a single copy gene and had two homologous genes in the tomato genome. Northern blot showed that LeFAD7was expressed in all organs and was especially abundant in leaf tissue. Meanwhile, expression of LeFAD7was induced by chilling stress (4 ℃),but was inhibited by high temperature (45 ℃), in leaves. Transgenic tomato plants were produced by integration of the antisense LeFAD7 DNA under the control of a CaMV35S promoter into the genome. Antisense transgenic plants with lower 18: 3 content could maintain a higher maximal photochemical efficiency (Fv/Fm)and O2 evolution rate than wild-type plants. These results suggested that silence of the LeFAD7 gene alleviated high-temperature stress. There was also a correlation between the low content of 18: 3 resulting from silence of the LeFAD7 gene and tolerance to high-temperature stress.

  16. Enhanced production of poly-γ-glutamic acid by a newly-isolated Bacillus subtilis.

    Science.gov (United States)

    Ju, Wan-Taek; Song, Yong-Su; Jung, Woo-Jin; Park, Ro-Dong

    2014-11-01

    Application of poly-gamma-glutamic acid (γ-PGA), an unusual macromolecular anionic polypeptide, is limited due to the high cost associated with its low productivity. Screening bacterial strains to find a more efficient producer is one approach to overcome this limitation. Strain MJ80 was isolated as a γ-PGA producer among 1,500 bacterial colonies obtained from soil samples. It was identified as Bacillus subtilis, based on the biochemical and morphological properties and 16S rDNA gene sequencing. It produced γ-PGA from both glutamic acid and soybean powder, identifying it as a facultative glutamic acid-metabolizing bacterium. After optimization of its culture conditions, B. subtilis MJ80 showed γ-PGA productivity of 75.5 and 68.7 g/l in 3 and 300 l jar fermenters for 3 days cultivation, respectively, the highest productivity reported to date, suggesting MJ80 to be a promising strain for γ-PGA production.

  17. Enhancement of lipid production and fatty acid profiling in Chlamydomonas reinhardtii, CC1010 for biodiesel production.

    Science.gov (United States)

    Karpagam, R; Preeti, R; Ashokkumar, B; Varalakshmi, P

    2015-11-01

    Lipid from microalgae is one of the putative oil resources to facilitate the biodiesel production during this era of energy dissipation and environmental pollution. In this study, the key parameters such as biomass productivity, lipid productivity and lipid content were evaluated at the early stationary phase of Chlamydomonas reinhardtii, CC1010 cultivated in nutrient starved (nitrogen, phosphorous), glucose (0.05%, 0.1%, 0.15% and 0.2%) and vitamin B12 supplementation (0.001%, 0.002% and 0.003%) in Tris-Acetate-Phosphate (TAP) medium. The lipid content in nitrogen starved media was 61% which is 2.34 folds higher than nutrient sufficient TAP medium. Glucose supplementation has lead to proportional increase in biomass productivity with the increasing concentration of glucose whereas vitamin B12 supplementations had not shown any influence in lipid and biomass production. Further, fatty acid methyl ester (FAME) profiling of C. reinhardtii, CC 1010 has revealed more than 80% of total SFA (saturated fatty acid) and MUFA (mono unsaturated fatty acid) content. Quality checking parameters of biodiesel like cetane number, saponification value, iodine number and degree of unsaturation were analyzed and the biodiesel fuel properties were found to be appropriate as per the international standards, EN 14214 and ASTM D6751. Conclusively, among all the treatments, nitrogen starvation with 0.1% glucose supplementation had yielded high lipid content in C. reinhardtii, CC 1010.

  18. The cell transmembrane pH gradient in tumors enhances cytotoxicity of specific weak acid chemotherapeutics.

    Science.gov (United States)

    Kozin, S V; Shkarin, P; Gerweck, L E

    2001-06-15

    The extracellular pH is lower in tumor than in normal tissue, whereas their intracellular pH is similar. In this study, we show that the tumor-specific pH gradient may be exploited for the treatment of cancer by weak acid chemotherapeutics. i.v.-injected glucose substantially decreased the electrode estimated extracellular pH in a xenografted human tumor while its intracellular pH, evaluated by (31)P magnetic resonance spectroscopy, remained virtually unchanged. The resulting increase in the average cell pH gradient caused a parallel increase in tumor growth delay by the weak acid chlorambucil (CHL). Regardless of glucose administration, the effect of CHL was significantly greater in tumors preirradiated with a large dose of ionizing radiation. This suggests that CHL was especially pronounced in radioresistant hypoxic cells possessing a larger transmembrane pH gradient. These results indicate that the naturally occurring cell pH gradient difference between tumor and normal tissue is a major and exploitable determinant of the uptake of weak acids in the complex tumor microenvironment. The use of such drugs may be especially effective in combination with radiation.

  19. Focal liver lesions detection and characterization: The advantages of gadoxetic acid-enhanced liver MRI

    Institute of Scientific and Technical Information of China (English)

    Stefano; Palmucci

    2014-01-01

    Since its clinical introduction, several studies in literature have investigated gadolinium ethoxybenzhyl diethylenetriaminepentaacetic acid or gadoxetic acid(Gd-EOB-DTPA) properties. Following contrast injection, it provides dynamic vascular phases(arterial, portal and equilibrium phases) and hepatobiliary phase, the latter due to its uptake by functional hepatocytes. The main advantages of Gd-EOB-DTPA of focal liver lesion detection and characterization are discussed in this paper. Namely, we focus on the possibility of distinguishing focal nodular hyperplasia(FNH) from hepatic adenoma(HA), the identification of early hepatocellular carcinoma(HCC) and the pre-operative assessment of metastasis in liver parenchyma. Regarding the differentiation between FNH and HA, adenoma typically appears hypointense in hepatobiliary phase, whereas FNH is isointense or hyperintense to the surrounding hepatic parenchyma. As for the identification of early HCCs, many papers recently published in literature have emphasized the contribution of hepatobiliary phase in the characterization of nodules without a typical hallmark of HCC. Atypical nodules(no hypervascularizaton observed on arterial phase and/or no hypovascular appearance on portal phase) with low signal intensity in the hepatobiliary phase, have a high probability of malignancy. Finally, regarding the evaluation of focal hepatic metastases, magnetic resonance pre-operative assessment using gadoxetic acid allows for more accurate diagnosis.

  20. Enhanced sidewall functionalization of single-wall carbon nanotubes using nitric acid.

    Science.gov (United States)

    Tobias, Gerard; Shao, Lidong; Ballesteros, Belin; Green, Malcolm L H

    2009-10-01

    When a sample of as-made single-walled carbon nanotubes (SWNTs) is treated with nitric acid, oxidation debris are formed due to the functionalization (mainly carboxylation) of the amorphous carbon present in the sample and a continuous coating along the carbon nanotube walls is created preventing the sidewall functionalization of the SWNTs. This oxidation debris can be easily removed by an aqueous base wash leaving behind a sample with a low degree of functionality. After removal of the amorphous carbon (by steam purification) from a sample of as-made SWNTs, the resulting purified SWNTs are readily carboxylated on the walls by nitric acid treatment. The use of steam for the purification of SWNTs samples allows the removal of the amorphous carbon and graphitic layers coating the metal particles present in the sample without altering the tubular structure of the SWNTs. The exposed metal particles can then be easily removed by an acid wash. Comparison between the steam treatment and molten sodium hydroxide treatment is made.

  1. Enhancing Cation Diffusion and Suppressing Anion Diffusion via Lewis-Acidic Polymer Electrolytes

    CERN Document Server

    Savoie, Brett M; Miller, Thomas F

    2016-01-01

    Solid polymer electrolytes (SPE) have the potential to increase both the energy density and stability of lithium-based batteries, but low Li-ion conductivity remains a barrier to technological viability. SPEs are designed to maximize Li-ion diffusivity relative to the anion, while maintaining sufficient salt solubility. It is thus remarkable that polyethylene oxide (PEO), the most widely used SPE, exhibits Li-ion diffusivity that is an order of magnitude smaller than that of typical counter-ions, such as TFSI, at moderate salt concentrations. Here, we show that Lewis-basic polymers like PEO intrinsically favor slow cation and rapid anion diffusion while this relationship can be reversed in Lewis-acidic polymers. Using molecular dynamics (MD) simulations, Lewis-acidic polyboranes are identified that achieve up to a ten-fold increase in Li-ion diffusivity and a significant decrease in anion diffusivity, relative to PEO. The results for this new class of Lewis-acidic SPEs illustrate a general principle for incre...

  2. Enhanced xylose recovery from oil palm empty fruit bunch by efficient acid hydrolysis.

    Science.gov (United States)

    Tan, Hooi Teng; Dykes, Gary A; Wu, Ta Yeong; Siow, Lee Fong

    2013-08-01

    Oil palm empty fruit bunch (EFB) is abundantly available in Malaysia and it is a potential source of xylose for the production of high-value added products. This study aimed to optimize the hydrolysis of EFB using dilute sulfuric acid (H2SO4) and phosphoric acid (H3PO4) via response surface methodology for maximum xylose recovery. Hydrolysis was carried out in an autoclave. An optimum xylose yield of 91.2 % was obtained at 116 °C using 2.0 % (v/v) H2SO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. A lower optimum xylose yield of 24.0 % was observed for dilute H3PO4 hydrolysis at 116 °C using 2.4 % (v/v) H3PO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. The optimized hydrolysis conditions suggested that EFB hydrolysis by H2SO4 resulted in a higher xylose yield at a lower acid concentration as compared to H3PO4.

  3. Branched-chain amino acids enhance cyst development in autosomal dominant polycystic kidney disease.

    Science.gov (United States)

    Yamamoto, Junya; Nishio, Saori; Hattanda, Fumihiko; Nakazawa, Daigo; Kimura, Toru; Sata, Michio; Makita, Minoru; Ishikawa, Yasunobu; Atsumi, Tatsuya

    2017-03-21

    Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the progressive development of kidney and liver cysts. The mammalian target of rapamycin (mTOR) cascade is one of the important pathways regulating cyst growth in ADPKD. Branched-chain amino acids (BCAAs), including leucine, play a crucial role to activate mTOR pathway. Therefore, we administered BCAA dissolved in the drinking water to Pkd1(flox/flox):Mx1-Cre (cystic) mice from four to 22 weeks of age after polyinosinic-polycytidylic acid-induced conditional Pkd1 knockout at two weeks of age. The BCAA group showed significantly greater kidney/body weight ratio and higher cystic index in both the kidney and liver compared to the placebo-treated mice. We found that the L-type amino acid transporter 1 that facilitates BCAA entry into cells is strongly expressed in cells lining the cysts. We also found increased cyst-lining cell proliferation and upregulation of mTOR and mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathways in the BCAA group. In vitro, we cultured renal epithelial cell lines from Pkd1 null mice with or without leucine. Leucine was found to stimulate cell proliferation, as well as activate mTOR and MAPK/ERK pathways in these cells. Thus, BCAA accelerated disease progression by mTOR and MAPK/ERK pathways. Hence, BCAA may be harmful to patients with ADPKD.

  4. Enhanced proton conductivity of Nafion composite membrane by incorporating phosphoric acid-loaded covalent organic framework

    Science.gov (United States)

    Yin, Yongheng; Li, Zhen; Yang, Xin; Cao, Li; Wang, Chongbin; Zhang, Bei; Wu, Hong; Jiang, Zhongyi

    2016-11-01

    Design and fabrication of efficient proton transport channels within solid electrolytes is crucial and challenging to new energy-relevant devices such as proton exchange membrane fuel cells (PEMFCs). In this study, the phosphoric acid (H3PO4) molecules are impregnated into SNW-1-type covalent organic frameworks (COFs) via vacuum assisted method. High loading of H3PO4 in SNW-1 and low guest leaching rate are achieved due to the similar diameter between H3PO4 and micropores in SNW-1. Then the COF-based composite membranes are fabricated for the first time with impregnated COFs (H3PO4@SNW-1) and Nafion matrix. For the composite membranes, the acid-base pairs formed between H3PO4@SNW-1 networks and Nafion optimize the interfacial interactions and hydrophilic domains. The acidic -PO3H2 groups in pores of H3PO4@SNW-1 provide abundant proton transfer sites. As a result, the continuous proton transfer channels with low energy barrier are created. At the filler content of 15 wt%, the composite membrane exhibits a superior proton conductivity of 0.0604 S cm-1 at 51% relative humidity and 80 °C. At the same time, the maximum power density of single fuel cell is 60.3% higher than that of the recast Nafion membrane.

  5. A pH dependent Raman and surface enhanced Raman spectroscopic studies of citrazinic acid aided by theoretical calculations

    Science.gov (United States)

    Sarkar, Sougata; Chowdhury, Joydeep; Dutta, Soumen; Pal, Tarasankar

    2016-12-01

    A pH dependent normal Raman scattering (NRS) and surface enhanced Raman scattering (SERS) spectral patterns of citrazinic acid (CZA), a biologically important molecule, have been investigated. The acid, with different pKa values (~ 4 and ~ 11) for the two different functional groups (-COOH and -OH groups), shows interesting range of color changes (yellow at pH ~ 14 and brown at pH ~ 2) with the variation in solution pH. Thus, depending upon the pH of the medium, CZA molecule can exist in various protonated and/or deprotonated forms. Here we have prescribed the existence different possible forms of CZA at different pH (Forms "C", "H" and "Dprot" at pH ~ 14 and Forms "A", "D", and "P" at pH ~ 2 respectively). The NRS spectra of these solutions and their respective SERS spectra over gold nanoparticles were recorded. The spectra clearly differ in their spectral profiles. For example the SERS spectra recorded with the CZA solution at pH ~ 2 shows blue shift for different bands compared to its NRS window e.g. 406 to 450 cm- 1, 616 to 632 cm- 1, 1332 to 1343 cm- 1 etc. Again, the most enhanced peak at ~ 1548 cm- 1 in NRS while in the SERS window this appears at ~ 1580 cm- 1. Similar observation was also made for CZA at pH ~ 14. For example, the 423 cm- 1 band in the NRS profile experience a blue shift and appears at ~ 447 cm- 1 in the SERS spectrum as well as other bands at ~ 850, ~ 1067 and ~ 1214 cm- 1 in the SERS window are markedly enhanced. It is also worth noting that the SERS spectra at the different pH also differ from each other. These spectral differences indicate the existence of various adsorptive forms of the CZA molecule depending upon the pH of the solution. Therefore based on the experimental findings we propose different possible molecular forms of CZA at different pH (acidic and alkaline) conditions. For example forms 'A', 'D' and 'P' existing in acidic pH (pH ~ 2) and three other deprotonated forms 'C', 'H' and 'Dprot' in alkaline pH (pH ~ 14). The DFT

  6. Enhanced suppression of tumor growth by concomitant treatment of human lung cancer cells with suberoylanilide hydroxamic acid and arsenic trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Chien, Chia-Wen [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan (China); Yao, Ju-Hsien [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China); Chang, Shih-Yu [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Lee, Pei-Chih [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China); Lee, Te-Chang, E-mail: bmtcl@ibms.sinica.edu.tw [Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan (China); Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China)

    2011-11-15

    The efficacy of arsenic trioxide (ATO) against acute promyelocytic leukemia (APL) and relapsed APL has been well documented. ATO may cause DNA damage by generating reactive oxygen intermediates. Suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, modulates gene and protein expression via histone-dependent or -independent pathways that may result in chromatin decondensation, cell cycle arrest, differentiation, and apoptosis. We investigated whether ATO and SAHA act synergistically to enhance the death of cancer cells. Our current findings showed that combined treatment with ATO and SAHA resulted in enhanced suppression of non-small-cell lung carcinoma in vitro in H1299 cells and in vivo in a xenograft mouse model. Flow cytometric analysis of annexin V+ cells showed that apoptotic cell death was significantly enhanced after combined treatment with ATO and SAHA. At the doses used, ATO did not interfere with cell cycle progression, but SAHA induced p21 expression and led to G1 arrest. A Comet assay demonstrated that ATO, but not SAHA, induced DNA strand breaks in H1299 cells; however, co-treatment with SAHA significantly increased ATO-induced DNA damage. Moreover, SAHA enhanced acetylation of histone H3 and sensitized genomic DNA to DNase I digestion. Our results suggest that SAHA may cause chromatin relaxation and increase cellular susceptibility to ATO-induced DNA damage. Combined administration of SAHA and ATO may be an effective approach to the treatment of lung cancer. -- Highlights: Black-Right-Pointing-Pointer ATO and SAHA are therapeutic agents with different action modes. Black-Right-Pointing-Pointer Combination of ATO and SAHA synergistically inhibits tumor cell growth. Black-Right-Pointing-Pointer SAHA loosens chromatin structure resulting in increased sensitivity to DNase I. Black-Right-Pointing-Pointer ATO-induced DNA damage and apoptosis are enhanced by co-treatment with SAHA.

  7. The utility of gadoteric acid in contrast-enhanced MRI: a review

    Directory of Open Access Journals (Sweden)

    Tartaro A

    2015-02-01

    Full Text Available Armando Tartaro, Marica Tina Maccarone Department of Neuroscience, Imaging and Clinical Sciences, and Institute for Advanced Biomedical Technologies (ITAB, “G d’Annunzio” University, Chieti-Pescara, Italy Abstract: Gadoteric acid (Dotarem® is a macrocyclic, paramagnetic, gadolinium-based contrast agent. It is used in the magnetic resonance imaging (MRI of the brain, spine, and associated tissues. Particularly, it is able to detect and visualize areas with disruption of the blood–brain barrier and/or abnormal vascularity. Gadoteric acid has been also approved for MR angiography of supraaortic vessels, cardiac MR (to detect myocardial infarctions, as well as whole-body MRI including abdominal, renal, pelvic, breast, and osteoarticular diseases. Cyclic chelates are more stable compared to linear chelates, and ionic chelates are more stable compared to nonionic chelates. Linear chelates have a greater likelihood of releasing free Gd3+ compared to cyclic chelates. Non-ionic chelates are more likely, compared to ionic chelates, to release Gd3+ from their chelates. Gadoteric acid is a cyclic ionic chelate and has the greatest kinetic stability among gadolinium-based contrast agents. In patients with chronic reduced kidney function, the use of gadolinium-based contrast agents leads to acute kidney injury and dialysis. The risk of acute kidney injury may increase with increasing dose of the contrast agents. Therefore, it is recommended to administer the lowest dose necessary for adequate imaging. The dose reduction allows protection the patients form potential risk of nephrogenic systemic fibrosis, a systemic reaction that is probably due to unbound Gd3+ ions deposited in body tissues. The dose of gadoteric acid should not exceed 0.1 mmol/kg body weight. More than one dose should not be used during a scan. Because of the lack of information on repeated administration, Dotarem® injections should not be repeated unless the interval between

  8. Enhancing separation of histidine from amino acids via free-flow affinity electrophoresis with gravity-induced uniform hydrodynamic flow.

    Science.gov (United States)

    Pang, Bo; Shao, Jing; Zhang, Jie; Geng, Jia-Zhen; Fan, Liu-Yin; Cao, Cheng-Xi; Hou, Jing-Li

    2012-03-01

    In this paper, a novel mode of free-flow affinity electrophoresis (FFAE) was developed to indirectly enhance the separation of free-flow electrophoresis (FFE). In the mode of FFAE, a Ni(II) with high electric charge density and histidine (His) is chosen as a model ligand and target solute, respectively. Through the controlling of experimental conditions (10 mM pH 6.0 Na(2)HPO(4)-NaH(2)PO(4) with 2.0 mM NiCl(2)·6H(2)O background buffer), Ni(II) can combine with His and the combination leads to the high electric charge density of affinity complex of His-Ni(II) in contrast to the low density of free His molecule. But the ligand has weak interaction with uninterested amino acids. Thus, the mobility of His existing as His-Ni(II) is greatly increased from 14.5×10(-8) m(2) V(-1) s(-1) to 30.2 × 10(-8) m(2) V(-1) s(-1), while those mobilities of uninterested amino acids are almost constant. By virtue of the mode, we developed the FFAE procedure and conducted the relevant experiments. The experiments demonstrated the following merits of the FFAE technique: (i) clear enhancement of separation between the target solute of His and uninterested amino acids; (ii) simplicity, and (iii) low cost. Furthermore, the technique was used for the continuous separation of His from its complex sample, and the purity of His was near to 100%. All of the results demonstrate the feasibility of affinity separation in FFE. The developed FFAE may be used in the separation and pretreatment of some biological molecules (e.g. peptides).

  9. Omega-3 Polyunsaturated Fatty Acids Enhance Cisplatin Efficacy in Gastric Cancer Cells by Inducing Apoptosis via ADORA1.

    Science.gov (United States)

    Sheng, Hong; Chen, Xuehua; Liu, Binya; Li, Pu; Cao, Weixin

    2016-01-01

    It has been suggested that administration of the omega-3 polyunsaturated fatty acids (ω-3 PUFAs), including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), can alter the toxicity and/or activity of several anticancer drugs in in vitro and in vivo studies. Here, we investigated the ability of ω-3 PUFAs to potentiate the antineoplastic activity of cisplatin (CDDP) in gastric cancer cells. The increase in CDDP-induced growth inhibition was measured by the IC50 values obtained when the cells were incubated with CDDP alone or with CDDP plus DHA or EPA. DHA and EPA enhanced the growth-inhibition activity of increasing concentrations of CDDP. The interactions between CDDP and DHA or EPA at the cellular level were assessed through the combination index (CI) method of Chou-Talalay. The results demonstrated synergism between CDDP and DHA or EPA in MKN45 cells. Cell cycle analysis showed that the combination treatment increased G0/G1 phase and S phase arrest, and significantly increased the number of apoptotic cells. According to our previous study, ω -3 PUFAs induce apoptosis of gastric cells via ADORA1, a subtype of adenosine receptor functionally related to cell death. The ADORA1 mRNA and protein expression was higher in the combination treatment than in the individual treatments. Notable, when GC cells were pretreated with DPCPX, a selective ADORA1 antagonist, the combination treatment effect on apoptosis was significantly reduced. Our results suggest that ω-3 PUFAs enhance the antineoplastic effects of CDDP in gastric cancer cells, and the synergistic effect between ω-3 PUFAs and CDDP is partly dependent on activating the ADORA1-mediated apoptosis pathway.

  10. Omega-3 free fatty acids suppress macrophage inflammasome activation by inhibiting NF-κB activation and enhancing autophagy.

    Directory of Open Access Journals (Sweden)

    Yolanda Williams-Bey

    Full Text Available The omega-3 (ω3 fatty acid docosahexaenoic acid (DHA can suppress inflammation, specifically IL-1β production through poorly understood molecular mechanisms. Here, we show that DHA reduces macrophage IL-1β production by limiting inflammasome activation. Exposure to DHA reduced IL-1β production by ligands that stimulate the NLRP3, AIM2, and NAIP5/NLRC4 inflammasomes. The inhibition required Free Fatty Acid Receptor (FFAR 4 (also known as GPR120, a G-protein coupled receptor (GPR known to bind DHA. The exposure of cells to DHA recruited the adapter protein β-arrestin1/2 to FFAR4, but not to a related lipid receptor. DHA treatment reduced the initial inflammasome priming step by suppressing the nuclear translocation of NF-κB. DHA also reduced IL-1β levels by enhancing autophagy in the cells. As a consequence macrophages derived from mice lacking the essential autophagy protein ATG7 were partially resistant to suppressive effects of DHA. Thus, DHA suppresses inflammasome activation by two distinct mechanisms, inhibiting the initial priming step and by augmenting autophagy, which limits inflammasome activity.

  11. Transcription activator-like effector nucleases mediated metabolic engineering for enhanced fatty acids production in Saccharomyces cerevisiae

    KAUST Repository

    Aouida, Mustapha

    2015-04-01

    Targeted engineering of microbial genomes holds much promise for diverse biotechnological applications. Transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats/Cas9 systems are capable of efficiently editing microbial genomes, including that of Saccharomyces cerevisiae. Here, we demonstrate the use of TALENs to edit the genome of S.cerevisiae with the aim of inducing the overproduction of fatty acids. Heterodimeric TALENs were designed to simultaneously edit the FAA1 and FAA4 genes encoding acyl-CoA synthetases in S.cerevisiae. Functional yeast double knockouts generated using these TALENs over-produce large amounts of free fatty acids into the cell. This study demonstrates the use of TALENs for targeted engineering of yeast and demonstrates that this technology can be used to stimulate the enhanced production of free fatty acids, which are potential substrates for biofuel production. This proof-of-principle study extends the utility of TALENs as excellent genome editing tools and highlights their potential use for metabolic engineering of yeast and other organisms, such as microalgae and plants, for biofuel production. © 2015 The Society for Biotechnology, Japan.

  12. The combination of vitamins and omega-3 fatty acids has an enhanced anti-inflammatory effect on microglia.

    Science.gov (United States)

    Kurtys, E; Eisel, U L M; Verkuyl, J M; Broersen, L M; Dierckx, R A J O; de Vries, E F J

    2016-10-01

    Neuroinflammation is a common phenomenon in the pathology of many brain diseases. In this paper we explore whether selected vitamins and fatty acids known to modulate inflammation exert an effect on microglia, the key cell type involved in neuroinflammation. Previously these nutrients have been shown to exert anti-inflammatory properties acting on specific inflammatory pathways. We hypothesized that combining nutrients acting on converging anti-inflammatory pathways may lead to enhanced anti-inflammatory properties as compared to the action of a single nutrient. In this study, we investigated the anti-inflammatory effect of combinations of nutrients based on the ability to inhibit the LPS-induced release of nitric oxide and interleukin-6 from BV-2 cells. Results show that omega-3 fatty acids, vitamins A and D can individually reduce the LPS-induced secretion of the pro-inflammatory cytokines by BV-2 cells. Moreover, we show that vitamins A, D and omega-3 fatty acids (docosahexaenoic and eicosapentaenoic) at concentrations where they individually had little effect, significantly reduced the secretion of the inflammatory mediator, nitric oxide, when they were combined. The conclusion of this study is that combining different nutrients acting on convergent anti-inflammatory pathways may result in an increased anti-inflammatory efficacy.

  13. Association with amino acids does not enhance efficacy of polymerized liposomes as a system for lung gene delivery

    Directory of Open Access Journals (Sweden)

    Elga eBernardo Bandeira De Melo

    2016-04-01

    Full Text Available Development of improved drug and gene delivery systems directly into the lungs is highly desirable given the important burden of respiratory diseases. We aimed to evaluate the safety and efficacy of liposomes composed of photopolymerized lipids (1,2-bis-(tricosa-10,12-diynoyl-sn-glycero-3-phosphocholine associated with amino acids as vectors for gene delivery into the lungs of healthy animals. Lipopolymer vesicles, in particular, are more stable than other types of liposomes. In this study, lipopolymers were associated with L-arginine, L-tryptophan, or L-cysteine. We hypothesized that the addition of these amino acids would enhance the efficacy of gene delivery to the lungs by the lipopolymers. L-Arginine showed the highest association efficiency due to its positive charge and better surface interactions. None of the formulations caused inflammation or altered lung mechanics, suggesting that these lipopolymers can be safely administered as aerosols. All formulations were able to induce eGFP mRNA expression in lung tissue, but the addition of amino acids reduced delivery efficacy when compared with the simple lipopolymer particle. These results indicate that this system could be further explored for gene or drug delivery targeting lung diseases.

  14. Transcription activator-like effector nucleases mediated metabolic engineering for enhanced fatty acids production in Saccharomyces cerevisiae.

    Science.gov (United States)

    Aouida, Mustapha; Li, Lixin; Mahjoub, Ali; Alshareef, Sahar; Ali, Zahir; Piatek, Agnieszka; Mahfouz, Magdy M

    2015-10-01

    Targeted engineering of microbial genomes holds much promise for diverse biotechnological applications. Transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats/Cas9 systems are capable of efficiently editing microbial genomes, including that of Saccharomyces cerevisiae. Here, we demonstrate the use of TALENs to edit the genome of S. cerevisiae with the aim of inducing the overproduction of fatty acids. Heterodimeric TALENs were designed to simultaneously edit the FAA1 and FAA4 genes encoding acyl-CoA synthetases in S. cerevisiae. Functional yeast double knockouts generated using these TALENs over-produce large amounts of free fatty acids into the cell. This study demonstrates the use of TALENs for targeted engineering of yeast and demonstrates that this technology can be used to stimulate the enhanced production of free fatty acids, which are potential substrates for biofuel production. This proof-of-principle study extends the utility of TALENs as excellent genome editing tools and highlights their potential use for metabolic engineering of yeast and other organisms, such as microalgae and plants, for biofuel production.

  15. Cell penetrating peptide-modified poly(lactic-co-glycolic acid) nanoparticles with enhanced cell internalization.

    Science.gov (United States)

    Steinbach, Jill M; Seo, Young-Eun; Saltzman, W Mark

    2016-01-01

    The surface modification of nanoparticles (NPs) can enhance the intracellular delivery of drugs, proteins, and genetic agents. Here we studied the effect of different surface ligands, including cell penetrating peptides (CPPs), on the cell binding and internalization of poly(lactic-co-glycolic) (PLGA) NPs. Relative to unmodified NPs, we observed that surface-modified NPs greatly enhanced cell internalization. Using one CPP, MPG (unabbreviated notation), that achieved the highest degree of internalization at both low and high surface modification densities, we evaluated the effect of two different NP surface chemistries on cell internalization. After 2h, avidin-MPG NPs enhanced cellular internalization by 5 to 26-fold relative to DSPE-MPG NP formulations. Yet, despite a 5-fold increase in MPG density on DSPE compared to Avidin NPs, both formulations resulted in similar internalization levels (48 and 64-fold, respectively) after 24h. Regardless of surface modification, all NPs were internalized through an energy-dependent, clathrin-mediated process, and became dispersed throughout the cell. Overall both Avidin- and DSPE-CPP modified NPs significantly increased internalization and offer promising delivery options for applications in which internalization presents challenges to efficacious delivery.

  16. Multiple heavy metals extraction and recovery from hazardous electroplating sludge waste via ultrasonically enhanced two-stage acid leaching.

    Science.gov (United States)

    Li, Chuncheng; Xie, Fengchun; Ma, Yang; Cai, Tingting; Li, Haiying; Huang, Zhiyuan; Yuan, Gaoqing

    2010-06-15

    An ultrasonically enhanced two-stage acid leaching process on extracting and recovering multiple heavy metals from actual electroplating sludge was studied in lab tests. It provided an effective technique for separation of valuable metals (Cu, Ni and Zn) from less valuable metals (Fe and Cr) in electroplating sludge. The efficiency of the process had been measured with the leaching efficiencies and recovery rates of the metals. Enhanced by ultrasonic power, the first-stage acid leaching demonstrated leaching rates of 96.72%, 97.77%, 98.00%, 53.03%, and 0.44% for Cu, Ni, Zn, Cr, and Fe respectively, effectively separated half of Cr and almost all of Fe from mixed metals. The subsequent second-stage leaching achieved leaching rates of 75.03%, 81.05%, 81.39%, 1.02%, and 0% for Cu, Ni, Zn, Cr, and Fe that further separated Cu, Ni, and Zn from mixed metals. With the stabilized two-stage ultrasonically enhanced leaching, the resulting over all recovery rates of Cu, Ni, Zn, Cr and Fe from electroplating sludge could be achieved at 97.42%, 98.46%, 98.63%, 98.32% and 100% respectively, with Cr and Fe in solids and the rest of the metals in an aqueous solution discharged from the leaching system. The process performance parameters studied were pH, ultrasonic power, and contact time. The results were also confirmed in an industrial pilot-scale test, and same high metal recoveries were performed.

  17. Clavulanic acid enhances glutamate transporter subtype I (GLT-1) expression and decreases reinforcing efficacy of cocaine in mice.

    Science.gov (United States)

    Kim, Jae; John, Joel; Langford, Dianne; Walker, Ellen; Ward, Sara; Rawls, Scott M

    2016-03-01

    The β-lactam antibiotic ceftriaxone (CTX) reduces cocaine reinforcement and relapse in preclinical assays through a mechanism involving activation of glutamate transporter subtype 1 (GLT-1). However, its poor brain penetrability and intravenous administration route may limit its therapeutic utility for indications related to CNS diseases. An alternative is clavulanic acid (CA), a structural analog of CTX that retains the β-lactam core required for GLT-1 activity but displays enhanced brain penetrability and oral activity relative to CTX. Here, we tested the hypothesis that CA (1, 10 mg/kg ip) would enhance GLT-1 expression and decrease cocaine self-administration (SA) in mice, but at lower doses than CTX. Experiments revealed that GLT-1 transporter expression in the nucleus accumbens of mice treated with repeated CA (1, 10 mg/kg) was enhanced relative to saline-treated mice. Repeated CA treatment (1 mg/kg) reduced the reinforcing efficacy of cocaine (0.56 mg/kg/inf) in mice maintained on a progressive-ratio (PR) schedule of reinforcement but did not affect acquisition of cocaine SA under fixed-ratio responding or acquisition or retention of learning. These findings suggest that the β-lactamase inhibitor CA can activate the cellular glutamate reuptake system in the brain reward circuit and reduce cocaine's reinforcing efficacy at 100-fold lower doses than CTX.

  18. Sucrose fed-batch strategy enhanced biomass, polysaccharide, and ganoderic acids production in fermentation of Ganoderma lucidum 5.26.

    Science.gov (United States)

    Wei, Zhen-hua; Liu, Lianliang; Guo, Xiao-feng; Li, Yan-jun; Hou, Bao-chao; Fan, Qiu-ling; Wang, Kai-xiang; Luo, Yingdi; Zhong, Jian-jiang

    2016-01-01

    Ganoderma, as a Chinese traditional medicine, has multiple bioactivities. However, industrial production was limited due to low yield during Ganoderma fermentation. In this work, sucrose was found to greatly enhance intracellular polysaccharide (IPS) content and specific extracellular polysaccharide (EPS) production rate. The mechanism was studied by analyzing the activities of enzymes related to polysaccharide biosynthesis. The results revealed that sucrose regulated the activities of phosphoglucomutase and phosphoglucose isomerase. When glucose and sucrose mixture was used as carbon source, biomass, polysaccharide and ganoderic acids (GAs) production was greatly enhanced. A sucrose fed-batch strategy was developed in 10-L bioreactor, and was scaled up to 300-L bioreactor. The biomass, EPS and IPS production was 25.5, 2.9 and 4.8 g/L, respectively, which was the highest biomass and IPS production in pilot scale. This study provides information for further understanding the regulation mechanism of Ganoderma polysaccharide biosynthesis. It demonstrates that sucrose fed-batch is a useful strategy for enhancing Ganoderma biomass, polysaccharide and GAs production.

  19. Colour stabilities of sour cherry juice concentrates enhanced with gallic acid and various plant extracts during storage.

    Science.gov (United States)

    Navruz, Ayşe; Türkyılmaz, Meltem; Özkan, Mehmet

    2016-04-15

    Gallic acid (GA) and pomegranate rind extract (PRE), cherry stem extract (CSE) and green tea extract (GTE) were added to sour cherry juice concentrates (SCJCs) to enhance the colour. Effects of these copigment sources on anthocyanins, colour and turbidity were investigated during storage at -20, 4 and 20°C for 110 days. Cyanidin-3-glucosylrutinoside (cyd-3-glu-rut, 75%) was the major anthocyanin, followed by cyanidin-3-rutinoside (cyd-3-rut, 23%) and cyanidin-3-sophoroside (cyd-3-soph, 2%). While GA (37-53%), PRE (27-77%) and GTE (44-119%) increased the stabilities of cyd-3-rut and cyd-3-glu-rut, CSE reduced (12-24%) the stabilities of all anthocyanins. Polymeric colour and turbidity values increased after the addition of all extracts and GA. The lowest turbidity value after 110 days of storage at 20°C was determined in the SCJC enhanced with PRE. We recommend the addition of PRE to SCJC for the enhancement of anthocyanin stability and colour intensity, and the reduction in turbidity.

  20. Enhanced photocatalytic activity of nanotube-like titania by sulfuric acid treatment

    Institute of Scientific and Technical Information of China (English)

    YANG Shao-gui; QUAN Xie; LI Xin-yong; FANG Ning; ZHANG Ning; ZHAO Hui-min

    2005-01-01

    The TiO2 nanotube sample was prepared via a NaOH solution in a Teflon vessel at 150℃. The as-prepared nanotubes were then treated with H2 SO4 solutions. The TiO2 nanotube has a crystalline structure with open-ended and multiwall morphologies. The TiO2 nanotubes before and after surface acid treatment were characterized by X-ray diffraction (XRD), scanning electron microscopy(SEM),transmission electron microscopy (TEM) and UV-VIS dispersive energy spectrophotometry (DRS). The photocatalytic activity of the samples was evaluated by photocatalytic degradation of acid orange Ⅱ in aqueous solutions. It was found that the order of photocatalytic activity was as follows: TiO2 nanotubes treated with 1.0 mol/L H2 SO4 solution (TiO2(1.0M H2SO4) nanotubes) > TiO2 nanotubes treated with 0.2 mol/L H2SO4 solution (TiO2(0.2MH2SO4) nanotubes) > TiO2 nanotubes > TiO2 powder. This was attributed to the fact that TiO2 nanotubes treated with H2 SO4 was composed of smaller particles and had higher specific surface areas. Furthermore, the smaller TiO2 particles were beneficial to the transfer and separation of photo-generated electrons and holes in the inner of and on the surface of TiO2 particles and reduced the recombination of photo-generated electrons and holes. Acid treatment was particularly effective for TiO2 nanotubes, this increase in activity was correlated with the concentration of H2 O4 solution.

  1. Clay ingestion enhances intestinal triacylglycerol hydrolysis and non-esterified fatty acid absorption.

    Science.gov (United States)

    Habold, Caroline; Reichardt, François; Le Maho, Yvon; Angel, Fabielle; Liewig, Nicole; Lignot, Jean-Hervé; Oudart, Hugues

    2009-07-01

    Consumption by animals and humans of earthy materials such as clay is often related to gut pathologies. Our aim was to determine the impact of kaolinite ingestion on glucose and NEFA transport through the intestinal mucosa. The expression of hexose transporters (Na/glucose co-transporter 1 (SGLT1), GLUT2, GLUT5) and of proteins involved in NEFA absorption (fatty acid transporter/cluster of differentiation 36 (FAT/CD36), fatty acid transport protein 4 (FATP4) and liver fatty acid binding protein (L-FABP)) was measured (1) in rats whose jejunum was perfused with a solution of kaolinite, and (2) in rats who ate spontaneously kaolinite pellets during 7 and 28 d. Also, we determined TAG and glucose absorption in the kaolinite-perfused group, and pancreatic lipase activity, gastric emptying and intestinal transit in rats orally administered with kaolinite. Glucose absorption was not affected by kaolinite perfusion or ingestion. However, kaolinite induced a significant increase in intestinal TAG hydrolysis and NEFA absorption. The cytoplasmic expression of L-FABP and FATP4 also increased due to kaolinite ingestion. NEFA may enter the enterocytes via endocytosis mainly since expression of NEFA transporters in the brush-border membrane was not affected by kaolinite. After uptake, rapid binding of NEFA by L-FABP and FATP4 could act as an intracellular NEFA buffer to prevent NEFA efflux. Increased TAG hydrolysis and NEFA absorption may be due to the adsorption properties of clay and also because kaolinite ingestion caused a slowing down of gastric emptying and intestinal transit.

  2. Enhanced anion electroadsorption into carbon molecular sieve electrodes in acidic media.

    Science.gov (United States)

    Eliad, Linoam; Salitra, Gregory; Pollak, Elad; Soffer, Abraham; Aurbach, Doron

    2005-11-08

    We previously showed that, for neutral electrolytes of small cations and relatively larger anions, it is possible to design certain pore sizes in active carbons that are large enough to electroadsorb cations but too small to allow anion electroadsorption. This situation leads to an electrical double-layer (EDL) capacitance that is significant only at potentials that are negative to the potential of zero charge (PZC); hence, much smaller capacitance is measured at potentials positive to the PZC. It was found that when the electrolyte is a strong acid (e.g., H(2)SO(4), HCl), a considerable capacitance is observed at positive potentials, even when the average pore size is too small to allow the insertion of large anions in neutral electrolyte solutions. This effect disappears when the pore size becomes considerably larger than the size of the ions. In this case, the EDL capacitance at positive potentials for both neutral and acidic solutions is comparable. The following four-step mechanism was found to comply best with the experimental data: (1) By acid catalysis, the protons form carbonium species within the conjugated carbon network. (2) The anions react with the carbonium ions, providing uncharged species in an activated state, which are chemibound as surface groups to the walls of the pores. (3) Because these surface groups are effectively much smaller in size than are the charged ions, they can migrate by chemical bond exchange within the carbon skeleton via constrictions (known to exist in microporous and molecular sieving carbons), which are too narrow to accommodate hydrated charged species. (4) Upon reaching wider spaces, the uncharged species are reionized and solvated by water molecules, which can fill small pores. The justification for the above mechanism is thoroughly discussed and demonstrated by the experimental results.

  3. Citric Acid Enhanced Copper Removal by a Novel Multi-amines Decorated Resin

    OpenAIRE

    Chen Ling; Fuqiang Liu; Zhiguo Pei; Xiaopeng Zhang; Mengmeng Wei; Yanhong Zhang; Lirong Zheng; Jing Zhang; Aimin Li; Baoshan Xing

    2015-01-01

    Cu removal by a novel multi-amines decorated resin (PAMD) from wastewater in the absence or presence of citric acid (CA) was examined. Adsorption capacity of Cu onto PAMD markedly increased by 186% to 5.07 mmol/g in the presence of CA, up to 7 times of that onto four commercial resins under the same conditions. Preloaded and kinetic studies demonstrated adsorption of [Cu-CA] complex instead of CA site-bridging and variations of adsorbate species were qualitatively illustrated. The interaction...

  4. Quality enhancement in the Japanese sea bass (Lateolabrax japonicas) fillets stored at 4°C by chitosan coating incorporated with citric acid or licorice extract.

    Science.gov (United States)

    Qiu, Xujian; Chen, Shengjun; Liu, Guangming; Yang, Qiuming

    2014-11-01

    The preserving effects of chitosan, chitosan and citric acid, chitosan and licorice extract on fresh Japanese sea bass fillets stored at 4 °C for 12 days were studied. Results showed that citric acid or licorice extract can enhance the preserving function of chitosan significantly by retarding lipid oxidation and inhibiting microbial growth as reflected in thiobarbituric acid reactive substances and total plate count, respectively. Both total volatile basic nitrogen values and sensory scores indicated chitosan and citric acid or licorice extract can significantly reduce the quality loss and extend the shelf life of Japanese sea bass fish fillets during refrigerated storage. Citric acid or licorice extract with chitosan could thus be applied in the seafood industry to enhance quality of fish fillets as natural preservatives.

  5. Molecular Characterization and Enhancement of Anticancer Activity of Caffeic Acid Phenethyl Ester by γ Cyclodextrin

    Science.gov (United States)

    Wadhwa, Renu; Nigam, Nupur; Bhargava, Priyanshu; Dhanjal, Jaspreet Kaur; Goyal, Sukriti; Grover, Abhinav; Sundar, Durai; Ishida, Yoshiyuki; Terao, Keiji; Kaul, Sunil C

    2016-01-01

    Caffeic Acid Phenethyl Ester (CAPE) is a key component in New Zealand propolis, known for a variety of health promoting and therapeutic potentials. We investigated the molecular mechanism of anticancer and anti-metastasis activities of CAPE. cDNA array performed on the control and CAPE-treated breast cancer cells revealed activation of DNA damage signaling involving upregulation of GADD45α and p53 tumor suppressor proteins. Molecular docking analysis revealed that CAPE is capable of disrupting mortalin-p53 complexes. We provide experimental evidence and demonstrate that CAPE induced disruption of mortalin-p53 complexes led to nuclear translocation and activation of p53 resulting in growth arrest in cancer cells. Furthermore, CAPE-treated cells exhibited downregulation of mortalin and several other key regulators of cell migration accountable for its anti-metastasis activity. Of note, we found that whereas CAPE was unstable in the culture medium (as it gets degraded into caffeic acid by secreted esterases), its complex with gamma cyclodextrin (γCD) showed high efficacy in anti-tumor and anti-metastasis assays in vitro and in vivo (when administered through either intraperitoneal or oral route). The data proposes that CAPE-γCD complex is a potent anti-cancer and anti-metastasis reagent. PMID:27698914

  6. Enhanced oral bioavailability and in vivo antioxidant activity of chlorogenic acid via liposomal formulation.

    Science.gov (United States)

    Feng, Yingshu; Sun, Congyong; Yuan, Yangyang; Zhu, Yuan; Wan, Jinyi; Firempong, Caleb Kesse; Omari-Siaw, Emmanuel; Xu, Yang; Pu, Zunqin; Yu, Jiangnan; Xu, Ximing

    2016-03-30

    In the present study, a formulation system consisting of cholesterol and phosphatidyl choline was used to prepare an effective chlorogenic acid-loaded liposome (CAL) with an improved oral bioavailability and an increased antioxidant activity. The developed liposomal formulation produced regular, spherical and multilamellar-shaped distribution nanoparticles. The pharmacokinetic analysis of CAL compared with chlorogenic acid (CA), showed a higher value of Cmax(6.42 ± 1.49 min versus 3.97 ± 0.39 min) and a delayed Tmax(15 min versus 10 min), with 1.29-fold increase in relative oral bioavailability. The tissue distribution in mice also demonstrated that CAL predominantly accumulated in the liver which indicated hepatic targeting potential of the drug. The increased activities of antioxidant enzymes (Total Superoxide Dismutase (T-SOD) and Glutathione Peroxidase (GSH-Px)) and total antioxidant capacity (T-AOC), in addition to decreased level of malondialdehyde (MDA) in CCl4-induced hepatotoxicity study further revealed that CAL exhibited significant hepatoprotective and antioxidant effects. Collectively, these findings present a liposomal formulation with significantly improved oral bioavailability and an increased in vivo antioxidant activity of CA.

  7. Synthesis of hierarchical SnO2 nanoflowers with enhanced acetic acid gas sensing properties

    Science.gov (United States)

    Jin, W. X.; Ma, S. Y.; Tie, Z. Z.; Li, W. Q.; Luo, J.; Cheng, L.; Xu, X. L.; Wang, T. T.; Jiang, X. H.; Mao, Y. Z.

    2015-10-01

    Different morphologies hierarchical flower-like tin dioxide (SnO2) nanostructures were fabricated by changing the volume ratio of glycol and de-ionized water (Vg:Vw = 0, 1:2, 1:1 and 2:1) under a template-free and low-cost hydrothermal method and subsequent calcinations. The architectures, morphologies and gas sensing performances of the products were characterized by X-ray diffraction patterns (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and gas-sensing measurement device. It can be observed that all the nanoflowers were composed of two-dimensional (2D) nanosheets, and the thickness of nanosheets is only about 9 nm when Vg:Vw = 1:1. The sensor based on the product of Vg:Vw = 1:1 exhibited excellent gas sensing performance toward 500 ppm acetic acid at 260 °C, and the response value of this sensor was about 153.6, which was above 7.5 times higher than that of ammonia (about 20.3). In addition, the 3D flower-like SnO2 nanostructures exhibited not only high response and selectivity to ppm level acetone, but also fast response and recovery time within 10 s, demonstrating it can be used as a potential candidate for detecting acetic acid. Finally, the possible formation mechanism was proposed, too.

  8. A Microfluidic Platform to design crosslinked Hyaluronic Acid Nanoparticles (cHANPs) for enhanced MRI

    Science.gov (United States)

    Russo, Maria; Bevilacqua, Paolo; Netti, Paolo Antonio; Torino, Enza

    2016-11-01

    Recent advancements in imaging diagnostics have focused on the use of nanostructures that entrap Magnetic Resonance Imaging (MRI) Contrast Agents (CAs), without the need to chemically modify the clinically approved compounds. Nevertheless, the exploitation of microfluidic platforms for their controlled and continuous production is still missing. Here, a microfluidic platform is used to synthesize crosslinked Hyaluronic Acid NanoParticles (cHANPs) in which a clinically relevant MRI-CAs, gadolinium diethylenetriamine penta-acetic acid (Gd-DTPA), is entrapped. This microfluidic process facilitates a high degree of control over particle synthesis, enabling the production of monodisperse particles as small as 35 nm. Furthermore, the interference of Gd-DTPA during polymer precipitation is overcome by finely tuning process parameters and leveraging the use of hydrophilic-lipophilic balance (HLB) of surfactants and pH conditions. For both production strategies proposed to design Gd-loaded cHANPs, a boosting of the relaxation rate T1 is observed since a T1 of 1562 is achieved with a 10 μM of Gd-loaded cHANPs while a similar value is reached with 100 μM of the relevant clinical Gd-DTPA in solution. The advanced microfluidic platform to synthesize intravascularly-injectable and completely biocompatible hydrogel nanoparticles entrapping clinically approved CAs enables the implementation of straightforward and scalable strategies in diagnostics and therapy applications.

  9. Enhanced nucleic acid amplification with blood in situ by wire-guided droplet manipulation (WDM).

    Science.gov (United States)

    Harshman, Dustin K; Reyes, Roberto; Park, Tu San; You, David J; Song, Jae-Young; Yoon, Jeong-Yeol

    2014-03-15

    There are many challenges facing the use of molecular biology to provide pertinent information in a timely, cost effective manner. Wire-guided droplet manipulation (WDM) is an emerging format for conducting molecular biology with unique characteristics to address these challenges. To demonstrate the use of WDM, an apparatus was designed and assembled to automate polymerase chain reaction (PCR) on a reprogrammable platform. WDM minimizes thermal resistance by convective heat transfer to a constantly moving droplet in direct contact with heated silicone oil. PCR amplification of the GAPDH gene was demonstrated at a speed of 8.67 s/cycle. Conventional PCR was shown to be inhibited by the presence of blood. WDM PCR utilizes molecular partitioning of nucleic acids and other PCR reagents from blood components, within the water-in-oil droplet, to increase PCR reaction efficiency with blood in situ. The ability to amplify nucleic acids in the presence of blood simplifies pre-treatment protocols towards true point-of-care diagnostic use. The 16s rRNA hypervariable regions V3 and V6 were amplified from Klebsiella pneumoniae genomic DNA with blood in situ. The detection limit of WDM PCR was 1 ng/μL or 10(5)genomes/μL with blood in situ. The application of WDM for rapid, automated detection of bacterial DNA from whole blood may have an enormous impact on the clinical diagnosis of infections in bloodstream or chronic wound/ulcer, and patient safety and morbidity.

  10. Crassulacean acid metabolism enhances underwater photosynthesis and diminishes photorespiration in the aquatic plant Isoetes australis.

    Science.gov (United States)

    Pedersen, Ole; Rich, Sarah Meghan; Pulido, Cristina; Cawthray, Gregory Robert; Colmer, Timothy David

    2011-04-01

    • Underwater photosynthesis by aquatic plants is often limited by low availability of CO(2), and photorespiration can be high. Some aquatic plants utilize crassulacean acid metabolism (CAM) photosynthesis. The benefits of CAM for increased underwater photosynthesis and suppression of photorespiration were evaluated for Isoetes australis, a submerged plant that inhabits shallow temporary rock pools. • Leaves high or low in malate were evaluated for underwater net photosynthesis and apparent photorespiration at a range of CO(2) and O(2) concentrations. • CAM activity was indicated by 9.7-fold higher leaf malate at dawn, compared with at dusk, and also by changes in the titratable acidity (μmol H(+) equivalents) of leaves. Leaves high in malate showed not only higher underwater net photosynthesis at low external CO(2) concentrations but also lower apparent photorespiration. Suppression by CAM of apparent photorespiration was evident at a range of O(2) concentrations, including values below air equilibrium. At a high O(2) concentration of 2.2-fold the atmospheric equilibrium concentration, net photosynthesis was reduced substantially and, although it remained positive in leaves containing high malate concentrations, it became negative in those low in malate. • CAM in aquatic plants enables higher rates of underwater net photosynthesis over large O(2) and CO(2) concentration ranges in floodwaters, via increased CO(2) fixation and suppression of photorespiration.

  11. Light Enhanced Hydrofluoric Acid Passivation: A Sensitive Technique for Detecting Bulk Silicon Defects.

    Science.gov (United States)

    Grant, Nicholas E

    2016-01-01

    A procedure to measure the bulk lifetime (>100 µsec) of silicon wafers by temporarily attaining a very high level of surface passivation when immersing the wafers in hydrofluoric acid (HF) is presented. By this procedure three critical steps are required to attain the bulk lifetime. Firstly, prior to immersing silicon wafers into HF, they are chemically cleaned and subsequently etched in 25% tetramethylammonium hydroxide. Secondly, the chemically treated wafers are then placed into a large plastic container filled with a mixture of HF and hydrochloric acid, and then centered over an inductive coil for photoconductance (PC) measurements. Thirdly, to inhibit surface recombination and measure the bulk lifetime, the wafers are illuminated at 0.2 suns for 1 min using a halogen lamp, the illumination is switched off, and a PC measurement is immediately taken. By this procedure, the characteristics of bulk silicon defects can be accurately determined. Furthermore, it is anticipated that a sensitive RT surface passivation technique will be imperative for examining bulk silicon defects when their concentration is low (<10(12) cm(-3)).

  12. Adaptive mutation of Acetobacter pasteurianus SKU1108 enhances acetic acid fermentation ability at high temperature.

    Science.gov (United States)

    Matsutani, Minenosuke; Nishikura, Mitsuteru; Saichana, Natsaran; Hatano, Tomoyuki; Masud-Tippayasak, Uraiwan; Theergool, Gunjana; Yakushi, Toshiharu; Matsushita, Kazunobu

    2013-05-20

    In vitro adaptation is one of the most challenging subjects in biology to understand adaptive evolution. Microbial adaptation to temperature is not only interesting in terms of understanding the adaptation mechanism, but also useful for industrial applications. In this study, we attempted the in vitro adaptation of Acetobacter pasteurianus SKU1108 by repeating its cultivation under high-temperature acetic acid fermentation conditions. As a result, thermo-adapted strains having the higher fermentation ability than the wild-type strain were obtained. Mutations and/or disruptions in several proteins of the adapted strains were detected with NGS sequencing technology. In particular, two different adapted strains had mutations or disruptions in three specific genes in common, suggesting that these genes are essential for thermotolerance or fermentation at higher temperature. In order to clarify their involvement in thermotolerance, two of the three genes were disrupted and their phenotype was examined. The results showed that mutations of the two proteins, MarR and an amino acid transporter, are partly responsible for higher fermentation ability and/or thermotolerance. Thus, it was suggested that these elevated abilities of the adapted strains are acquired by assembling several single gene mutations including the above two mutations.

  13. Enhancing the natural removal of As in a reactive fluvial confluence receiving acid drainage

    Science.gov (United States)

    Abarca, M. I.; Arce, G.; Montecinos, M.; Guerra, P. A.; Pasten, P.

    2014-12-01

    Fluvial confluences are natural reactors that can determine the fate of contaminants in watersheds receiving acid drainage. Hydrological, hydrodynamic and chemical factors determine distinct conditions for the formation of suspended particles of iron and aluminum oxyhydroxides. The chemical and physical properties of these particle assemblages (e.g. particle size, chemical composition) can vary according to inflow mixing ratios, hydrodynamic velocity profiles, and chemical composition of the flows mixing at the confluence. Due to their capacity to sorb metals, it is important to identify the optimal conditions for removing metals from the aqueous phase, particularly arsenic, a contaminant frequently found in acid drainage. We studied a river confluence in the Lluta watershed, located in the arid Chilean Altiplano. We performed field measurements and laboratory studies to find optimal mixing ratio for arsenic sorption onto oxyhydroxide particles at the confluence between the Azufre (pH=2, As=2 mg/L) and the Caracarani river (pH=8, Asplants could be used to engineer such intervention.Acknowledgements: Proyecto Fondecyt 1130936 and Proyecto CONICYT FONDAP 15110020

  14. Salicylic acid enhances antioxidant system in Brassica juncea grown under different levels of manganese.

    Science.gov (United States)

    Parashar, Akshaya; Yusuf, Mohammad; Fariduddin, Qazi; Ahmad, Aqil

    2014-09-01

    The aim was to explore the responses of varied doses of manganese in mustard plants and also to test the proposition that salicylic acid induced up-regulation of antioxidant system which protect photosynthetic apparatus. Seeds were sown in pots and allowed to germinate under natural environmental conditions. At 10 days stage, soils in the pots were enriched with different levels (0, 3, 6, or 9 mM) of Mn for three days and allowed to grow till 30 day stage. At 31st day, foliage of plants was sprayed with 10 μM of salicylic acid (SA) and then allowed to grow till 45 days. Then plants were harvested to assess various growth, leaf gas exchange traits and biochemical parameters. Mn-treated plants had diminished growth, water relations and photosynthetic attributes along with carbonic anhydrase activity whereas; the level of lipid peroxidation, electrolyte leakage, accumulation of H2O2 along with proline accumulation and antioxidant enzymes increased in a concentration dependent manner. Follow-up application of SA to the Mn-stressed plants improved growth, water relations and photosynthetic traits, accelerated the activity of antioxidant enzymes and also the accumulation of proline. SA mediated tolerance to Mn-stressed plants could have due to up-regulation of antioxidant enzymes and proline accumulation.

  15. Enhanced biocompatibility and antibacterial property of polyurethane materials modified with citric acid and chitosan.

    Science.gov (United States)

    Liu, Tian-Ming; Wu, Xing-Ze; Qiu, Yun-Ren

    2016-08-01

    Citric acid (CA) and chitosan (CS) were covalently immobilized on polyurethane (PU) materials to improve the biocompatibility and antibacterial property. The polyurethane pre-polymer with isocyanate group was synthesized by one pot method, and then grafted with citric acid, followed by blending with polyethersulfone (PES) to prepare the blend membrane by phase-inversion method so that chitosan can be grafted from the membrane via esterification and acylation reactions eventually. The native and modified membranes were characterized by attenuated total reflectance-Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy, scanning electron microscopy, water contact angle measurement, and tensile strength test. Protein adsorption, platelet adhesion, hemolysis assay, activated partial thromboplastin time, prothrombin time, thrombin time, and adsorption of Ca(2+) were executed to evaluate the blood compatibility of the membranes decorated by CA and CS. Particularly, the antibacterial activities on the modified membranes were evaluated based on a vitro antibacterial test. It could be concluded that the modified membrane had good anticoagulant property and antibacterial property.

  16. Usefulness of combining gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging and contrast-enhanced ultrasound for diagnosing the macroscopic classification of small hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tomoki; Aikata, Hiroshi; Hatooka, Masahiro; Morio, Kei; Morio, Reona; Kan, Hiromi; Fujino, Hatsue; Fukuhara, Takayuki; Masaki, Keiichi; Ohno, Atsushi; Naeshiro, Noriaki; Nakahara, Takashi; Honda, Yohji; Murakami, Eisuke; Kawaoka, Tomokazu; Tsuge, Masataka; Hiramatsu, Akira; Imamura, Michio; Kawakami, Yoshiiku; Hyogo, Hideyuki; Takahashi, Shoichi [Hiroshima University Hospital, Department of Gastroenterology and Metabolism, Hiroshima (Japan); Chayama, Kazuaki [Hiroshima University Hospital, Department of Gastroenterology and Metabolism, Hiroshima (Japan); Hiroshima University, Liver Research Project Center, Hiroshima (Japan)

    2015-11-15

    Non-simple nodules in hepatocellular carcinoma (HCC) correlate with poor prognosis. Therefore, we examined the diagnostic ability of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI) and contrast-enhanced ultrasound (CEUS) for diagnosing the macroscopic classification of small HCCs. A total of 85 surgically resected nodules (≤30 mm) were analyzed. HCCs were pathologically classified as simple nodular (SN) and non-SN. By evaluating hepatobiliary phase (HBP) of EOB-MRI and Kupffer phase of CEUS, the diagnostic abilities of both modalities to correctly distinguish between SN and non-SN were compared. Forty-six nodules were diagnosed as SN and the remaining 39 nodules as non-SN. The area under the ROC curve (AUROCs, 95 % confidence interval) for the diagnosis of non-SN were EOB-MRI, 0.786 (0.682-0.890): CEUS, 0.784 (0.679-0.889), in combination, 0.876 (0.792-0.959). The sensitivity, specificity, and accuracy were 64.1 %, 95.7 %, and 81.2 % in EOB-MRI, 56.4 %, 97.8 %, and 78.8 % in CEUS, and 84.6 %, 95.7 %, and 90.6 % in combination, respectively. High diagnostic ability was obtained when diagnosed in both modalities combined. The sensitivity was especially statistically significant compared to CEUS. Combined diagnosis by EOB-MRI and CEUS can provide high-quality imaging assessment for determining non-SN in small HCCs. (orig.)

  17. Mutagenesis of aspartic acid-116 enhances the ribonucleolytic activity and angiogenic potency of angiogenin.

    Science.gov (United States)

    Harper, J W; Vallee, B L

    1988-01-01

    Site-specific mutagenesis of the blood vessel-inducing protein angiogenin has been used to further explore both its homology to pancreatic ribonuclease and the functional roles of particular residues. Replacement of Asp-116 in angiogenin by either asparagine (D116N), alanine (D116A), or histidine (D116H) markedly enhances both its ribonucleolytic activity and angiogenic potency. Activity toward tRNA is 8-, 15-, and 18-fold greater than native angiogenin for D116N-, D116A-, and D116H-angiogenin, respectively. The enzymatic specificity of angiogenin, however, has been maintained. Thus, cleavage of 18S and 28S rRNA by the most active His-116 mutant yields the same pattern of polynucleotide products as from angiogenin, whereas there are only minor alterations in activity with cytidylyl(3',5')adenosine and uridylyl(3',5')-adenosine. Extensive biological assays on the chicken embryo chorioallantoic membrane demonstrate that D116H-angiogenin is one to two orders of magnitude more potent in inducing neovascularization than native angiogenin, which correlates well with enhanced enzymatic action. These results support the proposition that the enzymatic and angiogenic activities on angiogenin are interrelated. PMID:2459697

  18. Potential of wound dressing composed of hyaluronic acid containing epidermal growth factor to enhance cytokine production by fibroblasts.

    Science.gov (United States)

    Yamamoto, Akiko; Shimizu, Nahoko; Kuroyanagi, Yoshimitsu

    2013-12-01

    This study aimed to investigate the potential of a wound dressing composed of hyaluronic acid (HA) containing epidermal growth factor (EGF) to enhance cytokine production by fibroblasts. The present wound dressing has a two-layered spongy structure: an upper layer composed of crosslinked high-molecular-weight HA, and a lower layer composed of low-molecular-weight HA containing arginine (Arg) and vitamin C derivative (VC) with or without EGF. Human fibroblast-embedded collagen gel sheet (cultured dermal substitute: CDS) was elevated to the interface between the air and culture medium to create a wound surface model onto which each wound dressing was placed, which was followed by culture for 7 days. The EGF dressing (with EGF, Arg, VC) significantly enhanced the production of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) by CDS as compared to the EGF-free dressing (with Arg, VC). To evaluate if this enhanced production of VEGF and HGF achieved with the EGF dressing is sustained, a second experiment was conducted using a wound surface model. Each wound dressing was placed on the CDS in the wound surface model. Culture was then performed for 3 days (first period), after which each dressing was placed on another CDS for a further 3-day culture period (second period). The EGF dressing enhanced the production of VEGF and HGF by CDS during the first and second periods as compared to the corresponding production when using the EGF-free dressing. These results suggest that EGF can be maintained in the hydrated layer of a wound dressing composed of crosslinked high-molecular-weight HA.

  19. Facile formation of dendrimer-stabilized gold nanoparticles modified with diatrizoic acid for enhanced computed tomography imaging applications.

    Science.gov (United States)

    Peng, Chen; Li, Kangan; Cao, Xueyan; Xiao, Tingting; Hou, Wenxiu; Zheng, Linfeng; Guo, Rui; Shen, Mingwu; Zhang, Guixiang; Shi, Xiangyang

    2012-11-07

    We report a facile approach to forming dendrimer-stabilized gold nanoparticles (Au DSNPs) through the use of amine-terminated fifth-generation poly(amidoamine) (PAMAM) dendrimers modified by diatrizoic acid (G5.NH(2)-DTA) as stabilizers for enhanced computed tomography (CT) imaging applications. In this study, by simply mixing G5.NH(2)-DTA dendrimers with gold salt in aqueous solution at room temperature, dendrimer-entrapped gold nanoparticles (Au DENPs) with a mean core size of 2.5 nm were able to be spontaneously formed. Followed by an acetylation reaction to neutralize the dendrimer remaining terminal amines, Au DSNPs with a mean size of 6 nm were formed. The formed DTA-containing [(Au(0))(50)-G5.NHAc-DTA] DSNPs were characterized via different techniques. We show that the Au DSNPs are colloid stable in aqueous solution under different pH and temperature conditions. In vitro hemolytic assay, cytotoxicity assay, flow cytometry analysis, and cell morphology observation reveal that the formed Au DSNPs have good hemocompatibility and are non-cytotoxic at a concentration up to 3.0 μM. X-ray absorption coefficient measurements show that the DTA-containing Au DSNPs have enhanced attenuation intensity, much higher than that of [(Au(0))(50)-G5.NHAc] DENPs without DTA or Omnipaque at the same molar concentration of the active element (Au or iodine). The formed DTA-containing Au DSNPs can be used for CT imaging of cancer cells in vitro as well as for blood pool CT imaging of mice in vivo with significantly improved signal enhancement. With the two radiodense elements of Au and iodine incorporated within one particle, the formed DTA-containing Au DSNPs may be applicable for CT imaging of various biological systems with enhanced X-ray attenuation property and detection sensitivity.

  20. Enhanced lubrication on tissue and biomaterial surfaces through peptide-mediated binding of hyaluronic acid

    Science.gov (United States)

    Singh, Anirudha; Corvelli, Michael; Unterman, Shimon A.; Wepasnick, Kevin A.; McDonnell, Peter; Elisseeff, Jennifer H.

    2014-10-01

    Lubrication is key for the efficient function of devices and tissues with moving surfaces, such as articulating joints, ocular surfaces and the lungs. Indeed, lubrication dysfunction leads to increased friction and degeneration of these systems. Here, we present a polymer-peptide surface coating platform to non-covalently bind hyaluronic acid (HA), a natural lubricant in the body. Tissue surfaces treated with the HA-binding system exhibited higher lubricity values, and in vivo were able to retain HA in the articular joint and to bind ocular tissue surfaces. Biomaterials-mediated strategies that locally bind and concentrate HA could provide physical and biological benefits when used to treat tissue-lubricating dysfunction and to coat medical devices.

  1. Associations of Pseudomonas species and forage grasses enhance degradation of chlorinated benzoic acids in soil

    Energy Technology Data Exchange (ETDEWEB)

    Siciliano, S. D.

    1998-12-01

    Using chlorinated benzoic acid (CBA) as a model compound, this study attempted to show that microorganisms and plants can be used as bioremediation agents to clean up contaminated soil sites in a cost effective and environmentally friendly manner. CBA was used because it is present in soils contaminated with polychlorinated biphenyls (PCBs), or chlorinated pesticides. Sixteen forage grasses were screened in combination with 12 bacterial inoculants for their ability to promote the degradation of CBA in soil. Five associations of plants and bacteria were found to degrade CBA to a greater extent than plants without bacterial inoculants. Bacterial inoculants were shown to stimulate CBA degradation by altering the microbial community present on the root surface and thereby increasing the ability of this community to degrade CBA.

  2. Enhanced lubrication on tissue and biomaterial surfaces through peptide-mediated binding of hyaluronic acid.

    Science.gov (United States)

    Singh, Anirudha; Corvelli, Michael; Unterman, Shimon A; Wepasnick, Kevin A; McDonnell, Peter; Elisseeff, Jennifer H

    2014-10-01

    Lubrication is key for the efficient function of devices and tissues with moving surfaces, such as articulating joints, ocular surfaces and the lungs. Indeed, lubrication dysfunction leads to increased friction and degeneration of these systems. Here, we present a polymer-peptide surface coating platform to non-covalently bind hyaluronic acid (HA), a natural lubricant in the body. Tissue surfaces treated with the HA-binding system exhibited higher lubricity values, and in vivo were able to retain HA in the articular joint and to bind ocular tissue surfaces. Biomaterials-mediated strategies that locally bind and concentrate HA could provide physical and biological benefits when used to treat tissue-lubricating dysfunction and to coat medical devices.

  3. Enhanced diastereoselectivity via confinement: photoisomerization of 2,3-diphenylcyclopropane-1-carboxylic acid derivatives within zeolites.

    Science.gov (United States)

    Sivaguru, J; Sunoj, Raghavan B; Wada, Takehiko; Origane, Yumi; Inoue, Yoshihisa; Ramamurthy, Vaidhyanathan

    2004-10-01

    From the perspective of asymmetric induction, the photochemistry of 24 chiral esters and amides of cis-2,3-diphenylcyclopropane-1-carboxylic acid from excited singlet and triplet states has been investigated within zeolites. The chiral auxiliaries placed at a remote location from the isomerization site functioned far better within a zeolite than in solution. Generally, chiral auxiliaries with an aromatic or a carbonyl substituent performed better than the ones containing only alkyl substituents. A model based on cation-binding-dependent flexibility of the chiral auxiliary accounts for the observed variation in de between aryl (and carbonyl) and alkyl chiral auxiliaries within zeolites. Cation-dependent diastereomer switch was also observed in select examples.

  4. Structural characterization of an acidic Epimedium polysaccharide and its immune-enhancement activity.

    Science.gov (United States)

    Wu, Yi; Li, Youying; Liu, Chang; Li, Entao; Gao, Zhenzhen; Liu, Cui; Gu, Wei; Huang, Yee; Liu, Jiaguo; Wang, Deyun; Hu, Yuanliang

    2016-03-15

    One acidic polysaccharide named EPS-1 was isolated from the aqueous extract of the leaves of Epimedium acuminatum Franch. It may be composed of 1,4-linked α-d-GalpA, 1,3,4-linked α-d-GalpA, 1,6-linked β-d-Galp and terminal α-l-Rhap residues in a molar ratio of 11.0:1.0:1.0:1.0 by chemical and spectroscopic analysis. EPS-1 possessed immune modulation effects on peripheral T lymphocyte and immature chBM-DCs such as promoting the proliferation and cytokine secretion of these cells and increasing the phagocytosis ability of immature chBM-DCs.

  5. Two-stage dilute-acid and organic-solvent lignocellulosic pretreatment for enhanced bioprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Brodeur, G.; Telotte, J.; Stickel, J. J.; Ramakrishnan, S.

    2016-11-01

    A two stage pretreatment approach for biomass is developed in the current work in which dilute acid (DA) pretreatment is followed by a solvent based pretreatment (N-methyl morpholine N oxide -- NMMO). When the combined pretreatment (DAWNT) is applied to sugarcane bagasse and corn stover, the rates of hydrolysis and overall yields (>90%) are seen to dramatically improve and under certain conditions 48 h can be taken off the time of hydrolysis with the additional NMMO step to reach similar conversions. DAWNT shows a 2-fold increase in characteristic rates and also fractionates different components of biomass -- DA treatment removes the hemicellulose while the remaining cellulose is broken down by enzymatic hydrolysis after NMMO treatment to simple sugars. The remaining residual solid is high purity lignin. Future work will focus on developing a full scale economic analysis of DAWNT for use in biomass fractionation.

  6. Impact property enhancement of poly (lactic acid) with different flexible copolymers

    Science.gov (United States)

    Likittanaprasong, N.; Seadan, M.; Suttiruengwong, S.

    2015-07-01

    The objective of this work was to improve the impact property of Poly (lactic acid) (PLA) by blending with different copolymers. Six flexible copolymers, namely, acrylonitrile butadiene styrene (ABS) powder, Biomax, polybutyrate adipate co-terephthalate (PBAT), polyether block amide (PEBAX), ethylene-vinyl acetate (EVA) and ethylene acrylic elastomer (EAE), with loading less than 20wt% were used and compared. The rheological, mechanical and morphological properties of samples were investigated by melt flow index, tensile testing, impact testing and scanning electron microscope (SEM), respectively. It was found that PLA added 20wt% EAE showed the highest impact strength (59.5 kJ/m2), which was 22 times higher than neat PLA. The elongation at break was also increased by 12 folds compared to neat PLA. The SEM images showed good interface and distribution for PLA containing 20wt% EAE, 15 phr Biomax and 20 wt% PEBAX.

  7. SNBRFinder: A Sequence-Based Hybrid Algorithm for Enhanced Prediction of Nucleic Acid-Binding Residues.

    Directory of Open Access Journals (Sweden)

    Xiaoxia Yang

    Full Text Available Protein-nucleic acid interactions are central to various fundamental biological processes. Automated methods capable of reliably identifying DNA- and RNA-binding residues in protein sequence are assuming ever-increasing importance. The majority of current algorithms rely on feature-based prediction, but their accuracy remains to be further improved. Here we propose a sequence-based hybrid algorithm SNBRFinder (Sequence-based Nucleic acid-Binding Residue Finder by merging a feature predictor SNBRFinderF and a template predictor SNBRFinderT. SNBRFinderF was established using the support vector machine whose inputs include sequence profile and other complementary sequence descriptors, while SNBRFinderT was implemented with the sequence alignment algorithm based on profile hidden Markov models to capture the weakly homologous template of query sequence. Experimental results show that SNBRFinderF was clearly superior to the commonly used sequence profile-based predictor and SNBRFinderT can achieve comparable performance to the structure-based template methods. Leveraging the complementary relationship between these two predictors, SNBRFinder reasonably improved the performance of both DNA- and RNA-binding residue predictions. More importantly, the sequence-based hybrid prediction reached competitive performance relative to our previous structure-based counterpart. Our extensive and stringent comparisons show that SNBRFinder has obvious advantages over the existing sequence-based prediction algorithms. The value of our algorithm is highlighted by establishing an easy-to-use web server that is freely accessible at http://ibi.hzau.edu.cn/SNBRFinder.

  8. Retinoic acid treatment enhances lipid oxidation and inhibits lipid biosynthesis capacities in the liver of mice.

    Science.gov (United States)

    Amengual, Jaume; Ribot, Joan; Bonet, M Luisa; Palou, Andreu

    2010-01-01

    Vitamin A, mainly as retinoic acid (RA), is known to affect the development and function of adipose tissues. Treatment with RA reduces body weight and adiposity independent of changes in food intake in mice. Lipid metabolism in liver can have a major impact on whole body adiposity. The aim of this work was to investigate the effects of an in vivo treatment with RA on hepatic lipid metabolism in mice. Adult, standard diet-fed mice were treated with different doses of all-trans RA or vehicle (subcutaneous injection) for 4 days before sacrifice. Food intake and body weight changes during treatment were determined, as well as adiposity, liver composition, levels of circulating metabolites and lipoproteins and expression levels of key mRNA species in liver following sacrifice. RA treatment resulted in reduced body weight and adiposity, as expected. In the liver, RA treatment triggered an increase in the mRNA expression levels of peroxisome proliferator-activated receptor alpha, retinoid X receptor alpha, uncoupling protein 2, liver-type carnitine palmitoyltransferase 1, and carnitine/acylcarnitine carrier, and a reduction in the mRNA expression levels of sterol regulatory element binding protein 1c and fatty acid synthase. Consistent with the changes in gene expression, hepatic triacylglycerol content and circulating VLDL fraction were reduced and levels of circulating ketone bodies increased after RA treatment. These results point to a capacity of active vitamin A forms to shift liver lipid metabolism in vivo towards increased catabolism and reduced lipogenesis. These effects might contribute to the reduction of adiposity brought about by RA treatment.

  9. Amino acid substitutions in the FXYD motif enhance phospholemman-induced modulation of cardiac L-type calcium channels.

    Science.gov (United States)

    Guo, Kai; Wang, Xianming; Gao, Guofeng; Huang, Congxin; Elmslie, Keith S; Peterson, Blaise Z

    2010-11-01

    We have found that phospholemman (PLM) associates with and modulates the gating of cardiac L-type calcium channels (Wang et al., Biophys J 98: 1149-1159, 2010). The short 17 amino acid extracellular NH(2)-terminal domain of PLM contains a highly conserved PFTYD sequence that defines it as a member of the FXYD family of ion transport regulators. Although we have learned a great deal about PLM-dependent changes in calcium channel gating, little is known regarding the molecular mechanisms underlying the observed changes. Therefore, we investigated the role of the PFTYD segment in the modulation of cardiac calcium channels by individually replacing Pro-8, Phe-9, Thr-10, Tyr-11, and Asp-12 with alanine (P8A, F9A, T10A, Y11A, D12A). In addition, Asp-12 was changed to lysine (D12K) and cysteine (D12C). As expected, wild-type PLM significantly slows channel activation and deactivation and enhances voltage-dependent inactivation (VDI). We were surprised to find that amino acid substitutions at Thr-10 and Asp-12 significantly enhanced the ability of PLM to modulate Ca(V)1.2 gating. T10A exhibited a twofold enhancement of PLM-induced slowing of activation, whereas D12K and D12C dramatically enhanced PLM-induced increase of VDI. The PLM-induced slowing of channel closing was abrogated by D12A and D12C, whereas D12K and T10A failed to impact this effect. These studies demonstrate that the PFXYD motif is not necessary for the association of PLM with Ca(V)1.2. Instead, since altering the chemical and/or physical properties of the PFXYD segment alters the relative magnitudes of opposing PLM-induced effects on Ca(V)1.2 channel gating, PLM appears to play an important role in fine tuning the gating kinetics of cardiac calcium channels and likely plays an important role in shaping the cardiac action potential and regulating Ca(2+) dynamics in the heart.

  10. Preoperative evaluation of colorectal liver metastases: comparison between gadoxetic acid-enhanced 3.0-T MRI and contrast-enhanced MDCT with histopathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Scharitzer, M.; Ba-Ssalamah, A.; Ringl, H.; Koelblinger, C.; Weber, M. [Medical University of Vienna, Department of Radiology, Vienna (Austria); Gruenberger, T. [Medical University of Vienna, Department of Surgery, Vienna (Austria); Schima, W. [Department of Radiology, KH Goettlicher Heiland, KH der Barmherzigen Schwestern and St Josef-Krankenhaus, Vienna (Austria)

    2013-08-15

    The aim of this prospective study was to compare the diagnostic performance of 64-row MDCT and gadoxetic-acid-enhanced MRI at 3.0 T in patients with colorectal liver metastases in correlation with histopathological findings. Lesions detected at MDCT and MRI were interpreted by three blinded readers and compared with histopathological workup as the term of reference. Two subgroups of lesions were additionally evaluated: (1) metastases smaller than 10 mm and (2) lesions in patients with and without steatosis of the liver, assessed histopathologically. Surgery and histopathological workup revealed 81 colorectal liver metastases in 35 patients and diffuse metastatic involvement in 3 patients. In a lesion-by-lesion analysis, significant sensitivity differences could only be found for reader 1 (P = 0.035) and reader 3 (P = 0.003). For segment-based evaluation, MRI was more sensitive only for reader 3 (P = 0.012). The number of false-positive results ranged from 3 to 12 for MDCT and 8 to 11 for MRI evaluation. In the group of small lesions, the sensitivity differed significantly between both methods (P = 0.003). In patients with hepatic steatosis, MRI showed a trend toward better performance than MDCT, but without statistical performance. The 3.0-T MRI with liver-specific contrast agents is the preferred investigation in the preoperative setting, especially for the assessment of small colorectal liver metastases. (orig.)

  11. Electrochemical enhancement of glucose oxidase kinetics : gluconic acid production with anion exchange membrane reactor.

    Energy Technology Data Exchange (ETDEWEB)

    Hestekin, J.A.; Lin, Y. P.; Frank, J.; Snyder, S.; St. Martin, E.; Energy Systems

    2002-09-01

    Enzyme-catalysed reactions provide a means to perform many industrial processes because they enhance chemical reactions specifically and avoid the formation of by-products and the use of toxic organic solvents. Current enzyme applications range from laundry detergent supplements to the destruction of nerve gas agents. Although enzyme specificity is attractive there are also significant disadvantages to enzymatic catalysis. One of the principal disadvantages being relatively short lifetimes, ranging from a few hours to several days. However, literature has shown that by immobilizing an enzyme on a support matrix, the lifetime of the enzyme is increased since the rigidity of the support matrix helps prevent unfolding. Microfiltration membranes are often a good choice for enzyme attachment. The high surface area in the pores allows for enzyme attachment and reduction of mass transfer limitations.

  12. Surface Enhanced Raman Scattering for Quantification of p-Coumaric Acid Produced by Escherichia coli

    DEFF Research Database (Denmark)

    Morelli, Lidia; Zor, Kinga; Jendresen, Christian Bille

    2017-01-01

    engineered E. coli strains was successfully evaluated using SERS and confirmed with high-performance liquid chromatography. As this novel approach has potential to be automated and parallelized, it can be considered for high-throughput screening in metabolic engineering.......The number of newly developed genetic variants of microbial cell factories for production of biochemicals has been rapidly growing in recent years, leading to an increased need for new screening techniques. We developed a method based on surface-enhanced Raman scattering (SERS) coupled with liquid-liquid......-wafer signal variation of only 11.7%. LLE using dichloromethane as organic phase was combined with the detection in order to increase selectivity and sensitivity by decreasing the effect of interfering compounds from the analytes of interest. The difference in pHCA production yield between three genetically...

  13. VAMP/synaptobrevin cleavage by tetanus and botulinum neurotoxins is strongly enhanced by acidic liposomes.

    Science.gov (United States)

    Caccin, Paola; Rossetto, Ornella; Rigoni, Michela; Johnson, Eric; Schiavo, Giampietro; Montecucco, Cesare

    2003-05-01

    Tetanus and botulinum neurotoxins (TeNT and BoNTs) block neuroexocytosis via specific cleavage and inactivation of SNARE proteins. Such activity is exerted by the N-terminal 50 kDa light chain (L) domain, which is a zinc-dependent endopeptidase. TeNT, BoNT/B, /D, /F and /G cleave vesicle associated membrane protein (VAMP), a protein of the neurotransmitter-containing small synaptic vesicles, at different single peptide bonds. Since the proteolytic activity of these metalloproteases is higher on native VAMP inserted in synaptic vesicles than on recombinant VAMP, we have investigated the influence of liposomes of different lipid composition on this activity. We found that the rate of VAMP cleavage with all neurotoxins tested here is strongly enhanced by negatively charged lipid mixtures. This effect is at least partially due to the binding of the metalloprotease to the lipid membranes, with electrostatic interactions playing an important role.

  14. Extracellular acid block and acid-enhanced inactivation of the Ca2+-activated cation channel TRPM5 involve residues in the S3-S4 and S5-S6 extracellular domains.

    Science.gov (United States)

    Liu, Dan; Zhang, Zheng; Liman, Emily R

    2005-05-27

    TRPM5, a member of the superfamily of transient receptor potential ion channels, is essential for the detection of bitter, sweet, and amino acid tastes. In heterologous cell types it forms a nonselective cation channel that is activated by intracellular Ca(2+). TRPM5 is likely to be part of the taste transduction cascade, and regulators of TRPM5 are likely to affect taste sensation. In this report we show that TRPM5, but not the related channel TRPM4b, is potently blocked by extracellular acidification. External acidification has two effects, a fast reversible block of the current (IC(50) pH = 6.2) and a slower irreversible enhancement of current inactivation. Mutation of a single Glu residue in the S3-S4 linker and a His residue in the pore region each reduced sensitivity of TRPM5 currents to fast acid block (IC(50) pH = 5.8 for both), and the double mutant was nearly insensitive to acidic pH (IC(50) pH = 5.0). Prolonged exposure to acidic pH enhanced inactivation of TRPM5 currents, and mutant channels that were less sensitive to acid block were also less sensitive to acid-enhanced inactivation, suggesting an intimate association between the two processes. These processes are, however, distinct because the pore mutant H896N, which has normal sensitivity to acid block, shows significant recovery from acid-enhanced inactivation. These data show that extracellular acidification acts through specific residues on TRPM5 to block conduction through two distinct but related mechanisms and suggest a possible interaction between extracellular pH and activation and adaptation of bitter, sweet, and amino acid taste transduction.

  15. Early discrimination of nasopharyngeal carcinoma based on tissue deoxyribose nucleic acid surface-enhanced Raman spectroscopy analysis

    Science.gov (United States)

    Qiu, Sufang; Li, Chao; Lin, Jinyong; Xu, Yuanji; Lu, Jun; Huang, Qingting; Zou, Changyan; Chen, Chao; Xiao, Nanyang; Lin, Duo; Chen, Rong; Pan, Jianji; Feng, Shangyuan

    2016-12-01

    Surface-enhanced Raman spectroscopy (SERS) was employed to detect deoxyribose nucleic acid (DNA) variations associated with the development of nasopharyngeal carcinoma (NPC). Significant SERS spectral differences between the DNA extracted from early NPC, advanced NPC, and normal nasopharyngeal tissue specimens were observed at 678, 729, 788, 1337, 1421, 1506, and 1573 cm-1, which reflects the genetic variations in NPC. Principal component analysis combined with discriminant function analysis for early NPC discrimination yielded a diagnostic accuracy of 86.8%, 92.3%, and 87.9% for early NPC, advanced NPC, and normal nasopharyngeal tissue DNA, respectively. In this exploratory study, we demonstrated the potential of SERS for early detection of NPC based on the DNA molecular study of biopsy tissues.

  16. Enhancement of bacterial iron and sulfate respiration for in situ bioremediation of acid mine drainage sites: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Bilgin, A.A.; Harrington, J.M.; Silverstein, J. [ARCADIS G& amp; M, Highlands Ranch, CO (United States)

    2007-08-15

    The prevention of acid mine drainage (AMD) in situ is more attractive than down-gradient treatment alternatives that do not involve source control. AMD source control can be achieved by shifting the microbial activity in the sulfidic rock from pyrite oxidation to anaerobic heterotrophic activity. This is achieved by adding biodegradable organic carbon amendments to the sulfidic rock. This technique was applied to an abandoned coal mine pool in Pennsylvania. The pool had a pH of 3.0 to 3.5. Following treatment, near-neutral pH and decreased effluent heavy metal concentrations were achieved. In situ bioremediation by the enhancement of bacterial iron and sulfate reduction is a promising technology for AMD prevention.

  17. A broadband cavity enhanced absorption spectrometer for aircraft measurements of glyoxal, methylglyoxal, nitrous acid, nitrogen dioxide, and water vapor

    Science.gov (United States)

    Min, K.-E.; Washenfelder, R. A.; Dubé, W. P.; Langford, A. O.; Edwards, P. M.; Zarzana, K. J.; Stutz, J.; Lu, K.; Rohrer, F.; Zhang, Y.; Brown, S. S.

    2016-02-01

    We describe a two-channel broadband cavity enhanced absorption spectrometer (BBCEAS) for aircraft measurements of glyoxal (CHOCHO), methylglyoxal (CH3COCHO), nitrous acid (HONO), nitrogen dioxide (NO2), and water (H2O). The instrument spans 361-389 and 438-468 nm, using two light-emitting diodes (LEDs) and a single grating spectrometer with a charge-coupled device (CCD) detector. Robust performance is achieved using a custom optical mounting system, high-power LEDs with electronic on/off modulation, high-reflectivity cavity mirrors, and materials that minimize analyte surface losses. We have successfully deployed this instrument during two aircraft and two ground-based field campaigns to date. The demonstrated precision (2σ) for retrievals of CHOCHO, HONO and NO2 are 34, 350, and 80 parts per trillion (pptv) in 5 s. The accuracy is 5.8, 9.0, and 5.0 %, limited mainly by the available absorption cross sections.

  18. Poly(methyl vinyl ether-alt-maleic acid)-functionalized porous silicon nanoparticles for enhanced stability and cellular internalization.

    Science.gov (United States)

    Shahbazi, Mohammad-Ali; Almeida, Patrick V; Mäkilä, Ermei; Correia, Alexandra; Ferreira, Mónica P A; Kaasalainen, Martti; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2014-03-01

    Currently, developing a stable nanocarrier with high cellular internalization and low toxicity is a key bottleneck in nanomedicine. Here, we have developed a successful method to covalently conjugate poly(methyl vinyl ether-co-maleic acid) (PMVE-MA) copolymer on the surface of (3-aminopropyl)triethoxysilane-functionalized thermally carbonized porous silicon nanoparticles (APSTCPSi NPs), forming a surface negatively charged nanovehicle with unique properties. This polymer conjugated NPs could modify surface smoothness, charge, and hydrophilicity of the developed NPs, leading to considerable improvement in the colloidal and plasma stabilities via enhanced suspensibility and charge repulsion. Furthermore, despite the surface negative charge of the polymer-conjugated NPs, the cellular internalization was increased in both MDA-MB-231 and MCF-7 breast cancer cells. These results provide a proof-of-concept evidence that such polymer-based PSi nanocomposite can be extensively used as a promising candidate for intracellular drug delivery.

  19. A broadband cavity enhanced absorption spectrometer for aircraft measurements of glyoxal, methylglyoxal, nitrous acid, nitrogen dioxide, and water vapor

    Directory of Open Access Journals (Sweden)

    K.-E. Min

    2015-10-01

    Full Text Available We describe a two-channel broadband cavity enhanced absorption spectrometer (BBCEAS for aircraft measurements of glyoxal (CHOCHO, methylglyoxal (CH3COCHO, nitrous acid (HONO, nitrogen dioxide (NO2, and water (H2O. The instrument spans 361–389 and 438–468 nm, using two light emitting diodes (LEDs and a grating spectrometer with a charge-coupled device (CCD detector. Robust performance is achieved using a custom optical mounting system, high power LEDs with electronic on/off modulation, state-of-the-art cavity mirrors, and materials that minimize analyte surface losses. We have successfully deployed this instrument during two aircraft and two ground-based field campaigns to date. The demonstrated precision (2σ for retrievals of CHOCHO, HONO and NO2 are 34, 350 and 80 pptv in 5 s. The accuracy is 5.8, 9.0 and 5.0 % limited mainly by the available absorption cross sections.

  20. Enhanced intracellular delivery and antibacterial efficacy of enrofloxacin-loaded docosanoic acid solid lipid nanoparticles against intracellular Salmonella

    Science.gov (United States)

    Xie, Shuyu; Yang, Fei; Tao, Yanfei; Chen, Dongmei; Qu, Wei; Huang, Lingli; Liu, Zhenli; Pan, Yuanhu; Yuan, Zonghui

    2017-01-01

    Enrofloxacin-loaded docosanoic acid solid lipid nanoparticles (SLNs) with different physicochemical properties were developed to enhance activity against intracellular Salmonella. Their cellular uptake, intracellular elimination and antibacterial activity were studied in RAW 264.7 cells. During the experimental period, SLN-encapsulated enrofloxacin accumulated in the cells approximately 27.06–37.71 times more efficiently than free drugs at the same extracellular concentration. After incubation for 0.5 h, the intracellular enrofloxacin was enhanced from 0.336 to 1.147 μg/mg of protein as the sizes of nanoparticles were increased from 150 to 605 nm, and from 0.960 to 1.147 μg/mg of protein when the charge was improved from −8.1 to −24.9 mv. The cellular uptake was more significantly influenced by the size than it was by the charge, and was not affected by whether the charge was positive or negative. The elimination of optimal SLN-encapsulated enrofloxacin from the cells was significantly slower than that of free enrofloxacin after removing extracellular drug. The inhibition effect against intracellular Salmonella CVCC541 of 0.24 and 0.06 μg/mL encapsulated enrofloxacin was stronger than 0.6 μg/mL free drug after all of the incubation periods and at 48 h, respectively. Docosanoic acid SLNs are thus considered as a promising carrier for intracellular bacterial treatment. PMID:28112240