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Sample records for acid incorporating poloxamer

  1. Acid-Labile Amphiphilic PEO-b-PPO-b-PEO Copolymers: Degradable Poloxamer Analogs.

    Science.gov (United States)

    Worm, Matthias; Kang, Biao; Dingels, Carsten; Wurm, Frederik R; Frey, Holger

    2016-05-01

    Poly ((ethylene oxide)-b-(propylene oxide)-b-(ethylene oxide)) triblock copolymers commonly known as poloxamers or Pluronics constitute an important class of nonionic, biocompatible surfactants. Here, a method is reported to incorporate two acid-labile acetal moieties in the backbone of poloxamers to generate acid-cleavable nonionic surfactants. Poly(propylene oxide) is functionalized by means of an acetate-protected vinyl ether to introduce acetal units. Three cleavable PEO-PPO-PEO triblock copolymers (Mn,total = 6600, 8000, 9150 g·mol(-1) ; Mn,PEO = 2200, 3600, 4750 g·mol(-1) ) have been synthesized using anionic ring-opening polymerization. The amphiphilic copolymers exhibit narrow molecular weight distributions (Ð = 1.06-1.08). Surface tension measurements reveal surface-active behavior in aqueous solution comparable to established noncleavable poloxamers. Complete hydrolysis of the labile junctions after acidic treatment is verified by size exclusion chromatography. The block copolymers have been employed as surfactants in a miniemulsion polymerization to generate polystyrene (PS) nanoparticles with mean diameters of ≈200 nm and narrow size distribution, as determined by dynamic light scattering and scanning electron microscopy. Acid-triggered precipitation facilitates removal of surfactant fragments from the nanoparticles, which simplifies purification and enables nanoparticle precipitation "on demand."

  2. Formulation and characterization of poloxamer 407®: thermoreversible gel containing polymeric microparticles and hyaluronic acid

    Directory of Open Access Journals (Sweden)

    Gabriela Garrastazu Pereira

    2013-01-01

    Full Text Available The influence of the composition and preparation method on the sol-gel transition temperature (Tsol-gel and rheological response of poloxamer-based formulations was determined. Manual and more complex mechanical stirring were found to provide similar results. In addition, a linear dependence of Tsol-gel on the poloxamer content was observed in the range of concentrations analyzed, and a Poloxamer 407® concentration of 18% was selected. The addition of hyaluronic acid did not lead to significant changes in the Tsol-gel values. In contrast, the addition of microparticles caused a reduction in Tsol-gel without a significant reduction in gel strength, and pseudoplastic characteristics were observed, indicating that a thermoreversible gel was obtained with a rheology suitable for application in the treatment of burn wounds.

  3. Incorporating simvastatin/poloxamer 407 hydrogel into 3D-printed porous Ti6Al4V scaffolds for the promotion of angiogenesis, osseointegration and bone ingrowth.

    Science.gov (United States)

    Liu, Hao; Li, Wei; Liu, Can; Tan, Jie; Wang, Hong; Hai, Bao; Cai, Hong; Leng, Hui-Jie; Liu, Zhong-Jun; Song, Chun-Li

    2016-10-27

    Three-dimensional porous titanium alloys printed via electron beam melting have low stiffness similar to that of cortical bone and are promising scaffolds for orthopedic applications. However, the bio-inert nature of titanium alloy is poorly compatible with bone ingrowth. We previously observed that simvastatin/poloxamer 407 thermosensitive hydrogel induces endogenous angiogenic/osteogenic growth factors and promotes angiogenesis and osteogenesis, but the mechanical properties of this hydrogel are poor. The purpose of this study was to construct 3D-printed porous titanium scaffolds (pTi scaffolds) filled with simvastatin/hydrogel and evaluate the effects of this composite on osseointegration, bone ingrowth and neovascularization using a tibial defect rabbit model. Four and eight weeks after implantation, the bone volume, bone mineral density, mineral apposition rate, and push-in maximum force of the pTi scaffolds filled with simvastatin/hydrogel were significantly higher than those without simvastatin (p < 0.05). Moreover, filling with simvastatin/hydrogel significantly enhanced vascularization in and around the pTi scaffolds, and a significant correlation was observed between the volume of new bone and neovascularization (p < 0.01). In conclusion, incorporating simvastatin/poloxamer 407 hydrogel into pTi scaffolds significantly improves neovascularization, osseointegration and bone ingrowth.

  4. Evaluation of selected micronized poloxamers as tablet lubricants.

    Science.gov (United States)

    Desai, D; Zia, H; Quadir, A

    2007-10-01

    The primary objective of this study was to compare the lubrication properties of micronized poloxamer 188 (Lmicrotrol micro 68) and micronized poloxamer 407 (Lmicrotrol micro 127) with certain conventional lubricants such as magnesium stearate and stearic acid. The secondary objective was to use these micronized poloxamers as water-soluble tablet lubricants in preparation of effervecsent tablets. The results showed that these micronized poloxamers have superior lubrication properties compared with stearic acid, with no negative effect on tablet hardness, friability, disintegration, or dissolution. Moreover, lubricant mixing time had no significant effect on tablet properties when poloxamers were used as lubricants. Effervescent tablets also were produced successfully using micronized poloxamers as lubricants. The micronized poloxamers had a better lubrication effect in comparison with that of water-soluble lubricant l-leucine.

  5. Preparation, characterization and evaluation of the in vivo trypanocidal activity of ursolic acid-loaded solid dispersion with poloxamer 407 and sodium caprate

    Directory of Open Access Journals (Sweden)

    Josimar Oliveira Eloy

    2015-03-01

    Full Text Available Ursolic acid is a promising candidate for treatment of Chagas disease; however it has low aqueous solubility and intestinal absorption, which are both limiting factors for bioavailability. Among the strategies to enhance the solubility and dissolution of lipophilic drugs, solid dispersions are growing in popularity. In this study, we employed a mixture of the surfactants poloxamer 407 with sodium caprate to produce a solid dispersion containing ursolic acid aimed at enhancing both drug dissolution and in vivo trypanocidal activity. Compared to the physical mixture, the solid dispersion presented higher bulk density and smaller particle size. Fourier Transform Infrared Spectroscopy results showed hydrogen bonding intermolecular interactions between drug and poloxamer 407. X-ray diffractometry experiments revealed the conversion of the drug from its crystalline form to a more soluble amorphous structure. Consequently, the solubility of ursolic acid in the solid dispersion was increased and the drug dissolved in a fast and complete manner. Taken together with the oral absorption-enhancing property of sodium caprate, these results explained the increase of the in vivo trypanocidal activity of ursolic acid in solid dispersion, which also proved to be safe by cytotoxicity evaluation using the LLC-MK2 cell line.

  6. Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan-thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers.

    Science.gov (United States)

    Şenyiğit, Zeynep Ay; Karavana, Sinem Yaprak; İlem-Özdemir, Derya; Çalışkan, Çağrı; Waldner, Claudia; Şen, Sait; Bernkop-Schnürch, Andreas; Baloğlu, Esra

    2015-01-01

    This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan-thioglycolic acid conjugate) and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosanthioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in situ gelling properties at body temperature, which is in conflict with the aimed formulation property. Therefore, 2% chitosan gel formulation was found to be a more promising carrier system for intravesical administration of nanoparticles.

  7. Hybrid gold single crystals incorporating amino acids

    CERN Document Server

    Chen, Linfeng; Weber, Eva; Fitch, Andy N; Pokroy, Boaz

    2016-01-01

    Composite hybrid gold crystals are of profound interest in various research areas ranging from materials science to biology. Their importance is due to their unique properties and potential implementation, for example in sensing or in bio-nanomedicine. Here we report on the formation of hybrid organic-metal composites via the incorporation of selected amino acids histidine, aspartic acid, serine, glutamine, alanine, cysteine, and selenocystine into the crystal lattice of single crystals of gold. We used electron microscopy, chemical analysis and high-resolution synchrotron powder X ray diffraction to examine these composites. Crystal shape, as well as atomic concentrations of occluded amino acids and their impact on the crystal structure of gold, were determined. Concentration of the incorporated amino acid was highest for cysteine, followed by serine and aspartic acid. Our results indicate that the incorporation process probably occurs through a complex interaction of their individual functional groups with ...

  8. Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

    Directory of Open Access Journals (Sweden)

    Ay Şenyiğit Z

    2015-10-01

    Full Text Available Zeynep Ay Şenyiğit,1 Sinem Yaprak Karavana,1 Derya İlem-Özdemir,2 Çağrı Çalışkan,2 Claudia Waldner,3 Sait Şen,4 Andreas Bernkop-Schnürch,5 Esra Baloğlu1 1Faculty of Pharmacy, Department of Pharmaceutical Technology, Ege University, Bornova, İzmir, Turkey; 2Faculty of Pharmacy, Department of Radiopharmacy, Ege University, Bornova, İzmir, Turkey; 3ThioMatrix, Forschungs-Beratungs GmbH, Innsbruck, Austria; 4Faculty of Medicine, Department of Pathology, Ege University, Bornova, İzmir, Turkey; 5Institute of Pharmacy, Department of Pharmaceutical Technology, University of Innsbruck, Innsbruck, AustriaAbstract: This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan–thioglycolic acid conjugate and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosan-thioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in

  9. Mechanical, rheological and release behaviors of a poloxamer 407/ poloxamer 188/carbopol 940 thermosensitive composite hydrogel

    National Research Council Canada - National Science Library

    Chen, Jianping; Zhou, Rong; Li, Lin; Li, Bing; Zhang, Xia; Su, Jianyu

    2013-01-01

    The aims of this study were to prepare a thermosensitive composite hydrogel (TCH) by mixing 24% (w/v) poloxamer 407 (P407), 16% (w/v) poloxamer 188 (P188) and 0.1% (w/v) carbopol 940 (C940), and to determine the effect of natural borneol...

  10. Controlled extended octenidine release from a bacterial nanocellulose/Poloxamer hybrid system.

    Science.gov (United States)

    Alkhatib, Y; Dewaldt, M; Moritz, S; Nitzsche, R; Kralisch, D; Fischer, D

    2017-03-01

    Although bacterial nanocellulose (BNC) has been widely investigated in the last 10years as drug delivery system, up to now no long-term controlled release of drugs could be realized. Therefore, the aim of the present work was the development of a BNC-based drug delivery system that provides prolonged retention time for the antiseptic octenidine up to one week with improved mechanical and antimicrobial properties as well as a high biocompatibility. BNC was modified by incorporation of differently concentrated Poloxamers 338 and 407 as micelles and gels that were extensively investigated regarding size, surface charge, and dynamic viscosity. Depending on type and concentration of the Poloxamer, a retarded octenidine release up to one week could be accomplished. Additionally, superior material properties such as high compression stability and water binding could be achieved. The antimicrobial activity of octenidine against Staphylococcus aureus and Pseudomonas aeruginosa was not changed by the use of Poloxamers. Excellent biocompatibility of the Poloxamer loaded BNC could be demonstrated after local administration in a shell-less hen's egg model. In conclusion, a long-term delivery system consisting of BNC and Poloxamer could be developed for octenidine as a ready-to-use system e.g. for long-term dermal wound treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Electrodelivery of Drugs into Cancer Cells in the Presence of Poloxamer 188

    Directory of Open Access Journals (Sweden)

    Iana Tsoneva

    2010-01-01

    It was suggested that hydrophobic sections of poloxamer 188 molecules are incorporated into the edges of pores and that their hydrophilic parts act as brushy pore structures. The formation of brushy pores may reduce the expansion of pores and delay the irreversible electropermeability. Tumors were implanted subcutaneously in both flanks of nude mice using HeLa cells, transfected with genes for red fluorescent protein and luciferase. The volume of tumors stopped to grow after electrochemotherapy and the use of poloxamer 188 reduced the edema near the electrode and around the subcutaneously growing tumors.

  12. Effect of formulation pH on transdermal penetration of antiemetics formulated in poloxamer lecithin organogel.

    Science.gov (United States)

    Woodall, Rachel; Arnold, John J; McKay, Doug; Asbill, C Scott

    2013-01-01

    The purpose of this study was to assess the impact of altering formulation pH on the transdermal penetration of several commonly used antiemetic, weakly basic drugs incorporated into poloxamer lecithin organogel vehicle. Poloxamer lecithin organogel formulations containing promethazine hydrochloride (25 mg/mL), metoclopramide hydrochloride (10 mg/mL), and ondansetron hydrochloride (8 mg/mL) were examined for both drug release and transdermal penetration across porcine skin in modified Franz diffusion cells for a period of 24 hours. For the transdermal studies, each antiemetic drug was formulated at a pH above and below their acid dissociation constant (pKa) in an attempt to assure that the drug would be primarily in their respective ionized or non-ionized states. In addition, drug content in skin was assessed at the end of the 24-hour experiment. Drug content analysis was determined via high-performance liquid chromatography. As a percent of total drug release from the poloxamer lecithin organogel vehicle, promethazine hydrochloride demonstrated the most transdermal drug penetration after 24 hours (30.2% +/- 20.2%), followed by ondansetron hydrochloride (2.7% +/- 1.1%) and metoclopramide hydrochloride (1.8% +/- 1.6%). Subsequently, the pH of the Pluronic F-127 gel was adjusted in order to ensure that each antiemetic drug would be primarily in its unionized state. The transdermal permeation of each antiemetic drug primarily in its unionized state increased over that observed with the drug primarily in its ionized state after 24 hours (promethazine: 1.6-fold increase; metoclopramide: 1.3-fold increase; ondansetron: 1.8-fold increase). A similar trend was noted in the amount of each drug found in the skin after 24 hours (promethazine: 1.2-fold increase; metoclopramide: 2.4-fold increase; ondansetron: 3.0-fold increase). These results suggest that proper optimization of drug ionization state may be a useful strategy for compounding pharmacists to increase the efficacy

  13. Site specific incorporation of keto amino acids into proteins

    Science.gov (United States)

    Schultz, Peter G [La Jolla, CA; Wang, Lei [San Diego, CA

    2012-02-14

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  14. Site specific incorporation of keto amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G [La Jolla, CA; Wang, Lei [San Diego, CA

    2012-02-14

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  15. Site specific incorporation of keto amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G. (La Jolla, CA); Wang, Lei (San Diego, CA)

    2011-03-22

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  16. Site specific incorporation of keto amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G [La Jolla, CA; Wang, Lei [San Diego, CA

    2011-12-06

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  17. Incorporation of Chlorogenic Acids in Coffee Brew Melanoidins

    NARCIS (Netherlands)

    Bekedam, E.K.; Schols, H.A.; Boekel, van T.; Smit, G.

    2008-01-01

    The incorporation of chlorogenic acids (CGAs) and their subunits quinic and caffeic acids (QA and CA) in coffee brew melanoidins was studied. Fractions with different molecular weights, ionic charges, and ethanol solubilities were isolated from coffee brew. Fractions were saponified, and the release

  18. Permanent hair dye-incorporated hyaluronic acid nanoparticles.

    Science.gov (United States)

    Lee, Hye-Young; Jeong, Young-Il; Kim, Da-Hye; Choi, Ki-Choon

    2013-01-01

    We prepared p-phenylenediamine (PDA)-incorporated nanoparticles using hyaluronic acid (HA). PDA-incorporated HA nanoparticles have spherical shapes and sizes were less than 300 nm. The results of FT-IR spectra indicated that PDA-incorporated HA nanoparticles were formed by ion-complex formation between amine group of PDA and carboxyl group of HA. Furthermore, powder-X-ray diffractogram (XRD) measurement showed that intrinsic crystalline peak of PDA disappeared by formation of nanoparticle with HA at XRD measurement. These results indicated that PDA-incorporated HA nanoparticles were formed by ion-complex formation. At drug release study, the higher PDA contents induced faster release rate from nanoparticles. PDA-incorporated nanoparticles showed reduced intrinsic toxicity against HaCaT human keratinocyte cells at MTT assay and apoptosis assay. We suggest that PDA-incorporated HA nanoparticles are promising candidates for novel permanent hair dye.

  19. Poloxamer thermogel systems as medium for crystallization.

    Science.gov (United States)

    Cespi, Marco; Bonacucina, Giulia; Casettari, Luca; Mencarelli, Giovanna; Palmieri, Giovanni Filippo

    2012-03-01

    To prepare a thermoreversible gel system able to work as a medium for crystallization at around 20°C, allowing easy retrieval of crystals by simply decreasing the gel temperature. Lactose was selected has model substance for crystallization. Water solutions with different% of poloxamer 407, α-Lactose monohydrate, and ethanol were prepared and analysed by rheology to understand how the different components alter the gelling temperature. The systems with the required characteristics for lactose crystallization were prepared and the crystals recovered by cooling and then filtering the dispersion. Rheological analysis showed interaction between the poloxamer and lactose. Increasing the quantity of poloxamer or lactose lowered the gelation temperature while the addition of small amounts of ethanol had a modest effect on the same property. These data were used to identify the ideal concentration of the components in order to prepare a system matching the features of our purpose. Such system yielded high quality crystals, with well-defined geometry and narrow particle size distribution. Poloxamer is a very interesting polymer in that it is able to generate a reversible gelling medium from which crystals can be harvested by filtering, without the addition of any chemicals to promote the sol-gel transition.

  20. Safety assessment of poloxamers 101, 105, 108, 122, 123, 124, 181, 182, 183, 184, 185, 188, 212, 215, 217, 231, 234, 235, 237, 238, 282, 284, 288, 331, 333, 334, 335, 338, 401, 402, 403, and 407, poloxamer 105 benzoate, and poloxamer 182 dibenzoate as used in cosmetics.

    Science.gov (United States)

    Singh-Joy, Subhashni D; McLain, Valerie C

    2008-01-01

    Poloxamers are polyoxyethlyene, polyoxypropylene block polymers. The impurities of commercial grade Poloxamer 188, as an example, include low-molecular-weight substances (aldehydes and both formic and acetic acids), as well as 1,4-dioxane and residual ethylene oxide and propylene oxide. Most Poloxamers function in cosmetics as surfactants, emulsifying agents, cleansing agents, and/or solubilizing agents, and are used in 141 cosmetic products at concentrations from 0.005% to 20%. Poloxamers injected intravenously in animals are rapidly excreted in the urine, with some accumulation in lung, liver, brain, and kidney tissue. In humans, the plasma concentration of Poloxamer 188 (given intravenously) reached a maximum at 1 h, then reached a steady state. Poloxamers generally were ineffective in wound healing, but were effective in reducing postsurgical adhesions in several test systems. Poloxamers can cause hypercholesterolemia and hypertriglyceridemia in animals, but overall, they are relatively nontoxic to animals, with LD(50) values reported from 5 to 34.6 g/kg. Short-term intravenous doses up to 4 g/kg of Poloxamer 108 produced no change in body weights, but did result in diffuse hepatocellular vacuolization, renal tubular dilation in kidneys, and dose-dependent vacuolization of epithelial cells in the proximal convoluted tubules. A short-term inhalation toxicity study of Poloxamer 101 at 97 mg/m(3) identified slight alveolitis after 2 weeks of exposure, which subsided in the 2-week postexposure observation period. A short-term dermal toxicity study of Poloxamer 184 in rabbits at doses up to 1000 mg/kg produced slight erythema and slight intradermal inflammatory response on histological examination, but no dose-dependent body weight, hematology, blood chemistry, or organ weight changes. A 6-month feeding study in rats and dogs of Poloxamer 188 at exposures up to 5% in the diet produced no adverse effects. Likewise, Poloxamer 331 (tested up to 0.5 g/kg day(-1

  1. Method Development for Efficient Incorporation of Unnatural Amino Acids

    KAUST Repository

    Harris, Paul D.

    2014-04-01

    The synthesis of proteins bearing unnatural amino acids has the potential to enhance and elucidate many processes in biochemistry and molecular biology. There are two primary methods for site specific unnatural amino acid incorporation, both of which use the cell’s native protein translating machinery: in vitro chemical acylation of suppressor tRNAs and the use of orthogonal amino acyl tRNA synthetases. Total chemical synthesis is theoretically possible, but current methods severely limit the maximum size of the product protein. In vivo orthogonal synthetase methods suffer from the high cost of the unnatural amino acid. In this thesis I sought to address this limitation by increasing cell density, first in shake flasks and then in a bioreactor in order to increase the yield of protein per amount of unnatural amino acid used. In a parallel project, I used the in vitro chemical acylation system to incorporate several unnatural amino acids, key among them the fluorophore BODIPYFL, with the aim of producing site specifically fluorescently labeled protein for single molecule FRET studies. I demonstrated successful incorporation of these amino acids into the trial protein GFP, although incorporation was not demonstrated in the final target, FEN1. This also served to confirm the effectiveness of a new procedure developed for chemical acylation.

  2. The release and transdermal penetration of baclofen formulated in a poloxamer lecithin organogel.

    Science.gov (United States)

    Arnold, John J; Asbill, Scott

    2009-01-01

    The purpose of this study was to evaluate the in vitro release and ex vivo penetration of baclofen following incorporation into a 2% poloxamer lecithin organogel. Franz cells were utilized for both the release and penetration studies. Semi-permeable dialysis membranes were used as the model skin for the penetration study. Baclofen release and penetration at predetermined time points were assessed using high-performamce liquid chromatographic analysis. Results demonstrated that baclofen release from the poloxamer lecithin organogel was significantly higher than its penetration through porcine skin. The amount of baclofen released by the poloxamer lecithin organogel was linear up to 12 hours. Approximately 20% of applied drug was released over the duration of the study period. In comparison with drug released, the ex vivo penetration of baclofen through porcine skin was very low with only minute detectable quantities (significantly less than 1%) after the 12-hour study period. These results suggest that the request to include baclofen into a compounded poloxamer lecithin organogel should be approached cautiously by compounding pharmacists.

  3. Incorporation of conjugated linoleic acid (CLA and α-linolenic acid (LNA in pacu fillets

    Directory of Open Access Journals (Sweden)

    Deoclécio José Barilli

    2014-03-01

    Full Text Available The objective of this study was to evaluate the incorporation of conjugated linoleic acid and α-linolenic acid in fillets of pacu fish raised in net cages and fed diets enriched with these acids. The fish were fed for 49 days, and at the end of this period the fatty acid content in the fillets was determined by gas chromatography. Concentrations of α-linolenic acid, eicosapentaenoic acid, and the total omega-3 (n-3 fatty acid in the fillets increased, improving the n-6/n-3 ratio. In addition, the incorporation of conjugated linoleic acid in the fish fillets proved well established. This study showed that the use of diets enriched with conjugated linoleic acid and α-linolenic acid results in the incorporation of these acids in the of pacu fish fillets, improving their nutritional quality.

  4. Incorporation of chlorogenic acids in coffee brew melanoidins.

    Science.gov (United States)

    Bekedam, E Koen; Schols, Henk A; Van Boekel, Martinus A J S; Smit, Gerrit

    2008-03-26

    The incorporation of chlorogenic acids (CGAs) and their subunits quinic and caffeic acids (QA and CA) in coffee brew melanoidins was studied. Fractions with different molecular weights, ionic charges, and ethanol solubilities were isolated from coffee brew. Fractions were saponified, and the released QA and CA were quantified. For all melanoidin fractions, it was found that more QA than CA was released. QA levels correlated with melanoidin levels, indicating that QA is incorporated in melanoidins. The QA level was correlated with increasing ionic charge of the melanoidin populations, suggesting that QA may contribute to the negative charge and consequently is, most likely, not linked via its carboxyl group. The QA level correlated with the phenolic acid group level, as determined by Folin-Ciocalteu, indicating that QA was incorporated to a similar extent as the polyphenolic moiety from CGA. The QA and CA released from brew fractions by enzymes confirmed the incorporation of intact CGAs. Intact CGAs are proposed to be incorporated in melanoidins upon roasting via CA through mainly nonester linkages. This complex can be written as Mel=CA-QA, in which Mel represents the melanoidin backbone, =CA represents CA nonester-linked to the melanoidin backbone, and -QA represents QA ester-linked to CA. Additionally, a total of 12% of QA was identified in coffee brew, whereas only 6% was reported in the literature so far. The relevance of the additional QA on coffee brew stability is discussed.

  5. Characterization and micellization of a poloxamer block copolymer

    DEFF Research Database (Denmark)

    Hvidt, S.; Pedersen, Walther Batsberg

    2007-01-01

    Several poloxamers that are symmetrical EPE block copolymers (E and P are ethylene and propylene oxide, respectively) have been characterized by size exclusion chromatography on Superose columns in water. The poloxamers contain between 12 and 26 wt% of smaller-size UV-absorbing impurities...

  6. Tuning hardness in calcite by incorporation of amino acids

    Science.gov (United States)

    Kim, Yi-Yeoun; Carloni, Joseph D.; Demarchi, Beatrice; Sparks, David; Reid, David G.; Kunitake, Miki E.; Tang, Chiu C.; Duer, Melinda J.; Freeman, Colin L.; Pokroy, Boaz; Penkman, Kirsty; Harding, John H.; Estroff, Lara A.; Baker, Shefford P.; Meldrum, Fiona C.

    2016-08-01

    Structural biominerals are inorganic/organic composites that exhibit remarkable mechanical properties. However, the structure-property relationships of even the simplest building unit--mineral single crystals containing embedded macromolecules--remain poorly understood. Here, by means of a model biomineral made from calcite single crystals containing glycine (0-7 mol%) or aspartic acid (0-4 mol%), we elucidate the origin of the superior hardness of biogenic calcite. We analysed lattice distortions in these model crystals by using X-ray diffraction and molecular dynamics simulations, and by means of solid-state nuclear magnetic resonance show that the amino acids are incorporated as individual molecules. We also demonstrate that nanoindentation hardness increased with amino acid content, reaching values equivalent to their biogenic counterparts. A dislocation pinning model reveals that the enhanced hardness is determined by the force required to cut covalent bonds in the molecules.

  7. Incorporation of extracellular fatty acids by a fatty acid kinase-dependent pathway in Staphylococcus aureus.

    Science.gov (United States)

    Parsons, Joshua B; Frank, Matthew W; Jackson, Pamela; Subramanian, Chitra; Rock, Charles O

    2014-04-01

    Acyl-CoA and acyl-acyl carrier protein (ACP) synthetases activate exogenous fatty acids for incorporation into phospholipids in Gram-negative bacteria. However, Gram-positive bacteria utilize an acyltransferase pathway for the biogenesis of phosphatidic acid that begins with the acylation of sn-glycerol-3-phosphate by PlsY using an acyl-phosphate (acyl-PO4 ) intermediate. PlsX generates acyl-PO4 from the acyl-ACP end-products of fatty acid synthesis. The plsX gene of Staphylococcus aureus was inactivated and the resulting strain was both a fatty acid auxotroph and required de novo fatty acid synthesis for growth. Exogenous fatty acids were only incorporated into the 1-position and endogenous acyl groups were channeled into the 2-position of the phospholipids in strain PDJ39 (ΔplsX). Extracellular fatty acids were not elongated. Removal of the exogenous fatty acid supplement led to the rapid accumulation of intracellular acyl-ACP and the abrupt cessation of fatty acid synthesis. Extracts from the ΔplsX strain exhibited an ATP-dependent fatty acid kinase activity, and the acyl-PO4 was converted to acyl-ACP when purified PlsX is added. These data reveal the existence of a novel fatty acid kinase pathway for the incorporation of exogenous fatty acids into S. aureus phospholipids.

  8. Incorporation of conjugated linoleic acid and vaccenic acid into lipids from rat tissues and plasma

    DEFF Research Database (Denmark)

    Lund, Pia; Sejrsen, Kristen; Straarup, Ellen Marie

    2006-01-01

    The objective of this study was to determine the incorporation of conjugated linoleic acid (CLA) into triacylglycerols (TAG) and phospholipids (PL) of tissues and plasma, and to interpret the role of dietary-derived vaccenic acid (VA) in increasing the tissue content of CLA (c9,t11) and the influ...

  9. Lipid corralling and poloxamer squeeze-out in membranes

    DEFF Research Database (Denmark)

    Wu, G.H.; Majewski, J.; Ege, C.;

    2004-01-01

    Using x-ray scattering measurements we have quantitatively determined the effect of poloxamer 188 (P188), a polymer known to seal damaged membranes, on the structure of lipid monolayers. P188 selectively inserts into low lipid-density regions of the membrane and "corrals" lipid molecules to pack...... tightly, leading to unexpected Bragg peaks at low nominal lipid density and inducing lipid/poloxamer phase separation. At tighter lipid packing, the once inserted P188 is squeezed out, allowing the poloxamer to gracefully exit when the membrane integrity is restored....

  10. Incorporation and distribution of dihomo-gamma-linolenic acid, arachidonic acid, and eicosapentaenoic acid in cultured human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Punnonen, K.; Puustinen, T.; Jansen, C.T.

    1986-02-01

    Human keratinocytes in culture were labelled with /sup 14/C-dihomo-gamma-linolenic acid, /sup 14/C-arachidonic acid or /sup 14/C-eicosapentaenoic acid. All three eicosanoid precursor fatty acids were effectively incorporated into the cells. In phospholipids most of the radioactivity was recovered, in neutral lipids a substantial amount, and as free unesterified fatty acids only a minor amount. Most of the radioactivity was found in phosphatidylethanolamine which was also the major phospholipid as measured by phosphorous assay. The incorporation of dihomo-gamma-linolenic acid and arachidonic acid into lipid subfractions was essentially similar. Eicosapentaenoic acid was, however, much less effectively incorporated into phosphatidylinositol + phosphatidylserine and, correspondingly, more effectively into triacylglycerols as compared to the two other precursor fatty acids. Once incorporated, the distribution of all three precursor fatty acids was relatively stable, and only minor amounts of fatty acids were released into the culture medium during short term culture (two days). Our study demonstrates that eicosanoid precursor fatty acids are avidly taken up by human keratinocytes and esterified into membrane lipids. The clinical implication of this finding is that dietary manipulations might be employed to cause changes in the fatty acid composition of keratinocytes.

  11. Incorporation of oxygen into abscisic Acid and phaseic Acid from molecular oxygen.

    Science.gov (United States)

    Creelman, R A; Zeevaart, J A

    1984-05-01

    Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% (18)O(2) and 80% N(2) indicates that one atom of (18)O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase.Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing (18)O(2) indicates that one atom of (18)O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress.

  12. From Unnatural Amino Acid Incorporation to Artificial Metalloenzymes

    KAUST Repository

    Makki, Arwa A.

    2016-12-04

    Studies and development of artificial metalloenzymes have developed into vibrant areas of research. It is expected that artificial metalloenzymes will be able to combine the best of enzymatic and homogenous catalysis, that is, a broad catalytic scope, high selectivity and activity under mild, aqueous conditions. Artificial metalloenzyme consist of a host protein and a newly introduced artificial metal center. The host protein merely functions as ligand controlling selectivity and augmenting reactivity, while the metal center determines the reactivity. Potential applications range from catalytic production of fine chemicals and feedstock to electron transfer utilization (e.g. fuel cells, water splitting) and medical research (e.g. metabolic screening). Particularly modern asymmetric synthesis is expected to benefit from a successful combination of the power of biocatalysis (substrate conversion via multi-step or cascade reactions, potentially immortal catalyst, unparalleled selectivity and optimization by evolutionary methods) with the versatility and mechanism based optimization methods of homogeneous catalysis. However, so far systems are either limited in structural diversity (biotin-avidin technology) or fail to deliver the selectivities expected (covalent approaches). This thesis explores a novel strategy based on the site-selective incorporation of unnatural, metal binding amino acids into a host protein. The unnatural amino acids can either serve directly as metal binding centers can be used as anchoring points for artificial metallo-cofactors. The identification expression, purification and modification of a suitable protein scaffolds is fundamental to successfully develop this field. Chapter 2 and 3 detail a rational approach leading to a highly engineered host protein. Starting with fluorescent proteins, which combine high thermal and pH stability, high expression yields, and fluorescence for ease of quantification and monitoring an efficient and fast

  13. Incorporation of Palmitic Acid or Stearic Acid into Soybean Oils Using Enzymatic Interesterification.

    Science.gov (United States)

    Teh, Soek Sin; Voon, Phooi Tee; Hock Ong, Augustine Soon; Choo, Yuen May

    2016-09-01

    Incorporations of nature fatty acids which were palmitic acid and stearic acid into the end positions of soybean oils were done using sn-1,3 specific immobilised lipase from Rhizomucor miehei at different ratios in order to produce symmetrical triglycerides without changing the fatty acids at sn-2 position. The optimum ratio for the process was 25:75 w/w. There were 19.2% increase of SFA for P25 and 16% increase for S25 at the sn-1,3 positions. The research findings indicated that the structured lipids produced from enzymatic interesterification possessed a higher oxidative stability than soybean oil. The newly formed structured lipids (SUS type) could be good sources for various applications in food industry.

  14. Incorporated fish oil fatty acids prevent action potential shortening induced by circulating fish oil fatty acids

    Directory of Open Access Journals (Sweden)

    Hester M Den Ruijter

    2010-11-01

    Full Text Available Increased consumption of fatty fish, rich in omega-3 polyunsaturated fatty acids (3-PUFAs reduces the severity and number of arrhythmias. Long term 3-PUFA-intake modulates the activity of several cardiac ion channels leading to cardiac action potential shortening. Circulating 3-PUFAs in the bloodstream and incorporated 3-PUFAs in the cardiac membrane have a different mechanism to shorten the action potential. It is, however, unknown whether circulating 3-PUFAs in the bloodstream enhance or diminish the effects of incorporated 3-PUFAs. In the present study, we address this issue. Rabbits were fed a diet rich in fish oil (3 or sunflower oil (9, as control for 3 weeks. Ventricular myocytes were isolated by enzymatic dissociation and action potentials were measured using the perforated patch clamp technique in the absence and presence of acutely administered 3-PUFAs. Plasma of 3 fed rabbits contained more free eicosapentaenoic acid (EPA and isolated myocytes of 3 fed rabbits contained higher amounts of both EPA and docosahexaenoic acid (DHA in their sarcolemma compared to control. In the absence of acutely administered fatty acids, 3 myocytes had a shorter action potential with a more negative plateau than 9 myocytes. In the 9 myocytes, but not in the 3 myocytes, acute administration of a mixture of EPA+DHA shortened the action potential significantly. From these data we conclude that incorporated 3-PUFAs into the sarcolemma and acutely administered 3 fatty acids do not have a cumulative effect on action potential duration and morphology. As a consequence, patients with a high cardiac 3-PUFA status will probably not benefit from short term 3 supplementation as an antiarrhythmic therapy.

  15. Mechanical, Rheological and Release Behaviors of a Poloxamer 407/ Poloxamer 188/Carbopol 940 Thermosensitive Composite Hydrogel

    Directory of Open Access Journals (Sweden)

    Jianyu Su

    2013-10-01

    Full Text Available The aims of this study were to prepare a thermosensitive composite hydrogel (TCH by mixing 24% (w/v poloxamer 407 (P407, 16% (w/v poloxamer 188 (P188 and 0.1% (w/v carbopol 940 (C940, and to determine the effect of natural borneol/ (2-hydroxypropyl-β-cyclodextrin (NB/HP-β-CD inclusion complex on the phase transition temperature, mechanical, rheological properties, and release behaviors of the TCH using the tube inversion method, a texture analyzer, a rheometer, and in vitro release , respectively. The results showed that as the concentration of NB/HP-β-CD increased, the phase transition temperature of the TCH was increased from 37.26 to 38.34 °C and the mechanical properties of the TCH showed that the hardness, cohesiveness, strength, and adhesiveness were increased from 0.025 to 0.064 kg, 0.022 to 0.064 kg, 0.110 to 0.307 kg and 0.036 to 0.105 kg, respectively, but the rheological properties of the TCH showed that G′, G′′ and η were decreased from 7,760 to 157.50 Pa, 1,274 to 36.28 Pa and 1,252 to 25.37 Pas, respectively. The in vitro release showed that an increasing NB/HP-β-CD concentration decreased the release rate of NB from the TCH, but the amount of NB released was more than 96% at 60 min, which showed the TCH had good release behavior.

  16. Enzymatically mediated incorporation of 2-chlorophenol 4-chlorophenol into humic acids

    DEFF Research Database (Denmark)

    Lassen, P.; Randall, A.; Jørgensen, O.;

    1994-01-01

    A possible route to chlorinated humic substances in the environment, is an indirect chlorination of humic material by enzymatically mediated incorporation of low molecular weight organo-chlorine compounds into the humic skeleton. The enzymatically mediated incorporation of 2-chlorophenol and 4-ch......-chlorophenol into humic acids by Horseradish Peroxidase is reported. The incorporation is accompanied by a significant polymerization of the chlorophenols. The stability of the chlorinated humic acids as well as the environmental implication are discussed....

  17. A novel mucoadhesive polymer film composed of carbopol, poloxamer and hydroxypropylmethylcellulose.

    Science.gov (United States)

    Kim, Tae Hee; Ahn, Jae Soon; Choi, Hoo Kyun; Choi, Yun Jaie; Cho, Chong Su

    2007-03-01

    Using the casting method novel mucoadhesive polymer blend film consisting of Carbopol, poloxamer, and hydroxypropylmethylcellulose (HPMC) was prepared and characterized. Triamcinolone acetonide (TAA) was loaded into Carbopol/poloxamer/HPMC polymer blend film. Carbonyl band of Carbopol in Carbopol/poloxamer/HPMC shifted to longer wavenumber than that of Carbopol in Carbopol/poloxamer due to the hydrogen bonding among Carbopol, poloxamer, and HPMC. Tan delta peak assigned to glass transition temperature (Tg) of HPMC shifted to low temperature due to increased flexibility caused by increased poloxamer content in polymer blend films. Swelling ratio of Carbopol/poloxamer/HPMC films was lowest in Carbopoll poloxamer/HPMC at mixing ratio of 35/30/35 (wt/wt/wt). Adhesive force of Carbopol/poloxamer/HPMC films increased with increasing HPMC content in Carbopol/poloxamer/HPMC polymer blend film and increasing hydroxypropyl group content in HPMC due to hydrophobic property of HPMC although bioadhesive force was highest at mixing ratio of 35/30/35 (wt/wt/ wt). Release of TAA from TAA-loaded Carbopol/poloxamer/HPMC polymer blend film in vitro increased with increasing loading content of drug.

  18. Incorporation of Specific Fatty Acid Precursors During Spore Germination and Outgrowth in Bacillus thuringiensis

    Science.gov (United States)

    Nickerson, Kenneth W.; Bulla, Lee A.

    1980-01-01

    The selective incorporation of precursors specific for individual fatty acids in germinating and outgrowing spores of Bacillus thuringiensis is described. The specific precursors utilized were [14C]butyrate, -isobutyrate, -valerate, and -isovalerate, which were incorporated into even-numbered normal-chain isomers, even-numbered iso-isomers, odd-numbered normal-chain acids, and odd-numbered isohomologs, respectively. This preferential incorporation by B. thuringiensis allows the terminal carbons of specific normal and branched-chain fatty acids, contained within the cytoplasmic membrane, to be labeled with 14C and, potentially, 13C. PMID:16345590

  19. Performance of structured lipids incorporating selected phenolic and ascorbic acids.

    Science.gov (United States)

    Gruczynska, Eliza; Przybylski, Roman; Aladedunye, Felix

    2015-04-15

    Conditions applied during frying require antioxidant which is stable at these conditions and provides protection for frying oil and fried food. Novel structured lipids containing nutraceuticals and antioxidants were formed by enzymatic transesterification, exploring canola oil and naturally occurring antioxidants such as ascorbic and selected phenolic acids as substrates. Lipozyme RM IM lipase from Rhizomucor miehei was used as biocatalyst. Frying performance and oxidative stability of the final transesterification products were evaluated. The novel lipids showed significantly improved frying performance compared to canola oil. Oxidative stability assessment of the structured lipids showed significant improvement in resistance to oxidative deterioration compared to original canola oil. Interestingly, the presence of ascorbic acid in an acylglycerol structure protected α-tocopherol against thermal degradation, which was not observed for the phenolic acids. Developed structured lipids containing nutraceuticals and antioxidants may directly affect nutritional properties of lipids also offering nutraceutical ingredients for food formulation.

  20. A study of micronized poloxamers as lubricants in direct compression of tablets.

    Science.gov (United States)

    Muzíková, Jitka; Vyhlídalová, Barbora; Pekárek, Tomás

    2013-01-01

    The study evaluates the micronized poloxamers Lptrol micro127 (poloxamer 407) and Lptrol micro 68 (poloxamer 188) as lubricants in combination with the dry binders microcrystalline cellulose and spray-dried lactose. Magnesium stearate was employed as the comparative lubricant. The parameters under study included energy for friction, plasticity, ejection force, tensile strength of tablets, and disintegration time of tablets. The factors of influence were the concentration of lubricants, compression force, and mixing parameters. The lubricating effect of micronized poloxamers was smaller than that of magnesium stearate. Higher concentrations of poloxamers decreased the tensile strength of tablets from microcrystalline cellulose, shortened the disintegration time, and slightly prolonged the disintegration time in the case of spray-dried lactose. Parameters of mixing of dry binders with poloxamers influenced the tested parameters of compression more in the case of spray-dried lactose. In microcrystalline cellulose, they influenced more the tensile strength and disintegration time of tablets.

  1. Stability assessment of injectable castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulsifier films.

    Science.gov (United States)

    Tamilvanan, S; Kumar, B Ajith; Senthilkumar, S R; Baskar, Raj; Sekharan, T Raja

    2010-06-01

    The objectives of the present work were to prepare castor oil-based nano-sized emulsion containing cationic droplets stabilized by poloxamer-chitosan emulgator film and to assess the kinetic stability of the prepared cationic emulsion after subjecting it to thermal processing and freeze-thaw cycling. Presence of cryoprotectants (5%, w/w, sucrose +5%, w/w, sorbitol) improved the stability of emulsions to droplet aggregation during freeze-thaw cycling. After storing the emulsion at 4 degrees C, 25 degrees C, and 37 degrees C over a period of up to 6 months, no significant change was noted in mean diameter of the dispersed oil droplets. However, the emulsion stored at the highest temperature did show a progressive decrease in the pH and zeta potential values, whereas the emulsion kept at the lowest temperatures did not. This indicates that at 37 degrees C, free fatty acids were formed from the castor oil, and consequently, the liberated free fatty acids were responsible for the reduction in the emulsion pH and zeta potential values. Thus, the injectable castor oil-based nano-sized emulsion could be useful for incorporating various active pharmaceutical ingredients that are in size from small molecular drugs to large macromolecules such as oligonucleotides.

  2. Comprehensive two-dimensional liquid chromatographic analysis of poloxamers.

    Science.gov (United States)

    Malik, Muhammad Imran; Lee, Sanghoon; Chang, Taihyun

    2016-04-15

    Poloxamers are low molar mass triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), having number of applications as non-ionic surfactants. Comprehensive one and two-dimensional liquid chromatographic (LC) analysis of these materials is proposed in this study. The separation of oligomers of both types (PEO and PPO) is demonstrated for several commercial poloxamers. This is accomplished at the critical conditions for one of the block while interaction for the other block. Reversed phase LC at CAP of PEO allowed for oligomeric separation of triblock copolymers with regard to PPO block whereas normal phase LC at CAP of PPO renders oligomeric separation with respect to PEO block. The oligomeric separation with regard to PEO and PPO are coupled online (comprehensive 2D-LC) to reveal two-dimensional contour plots by unconventional 2D IC×IC (interaction chromatography) coupling. The study provides chemical composition mapping of both PEO and PPO, equivalent to combined molar mass and chemical composition mapping for several commercial poloxamers.

  3. Site-specific incorporation of redox active amino acids into proteins

    Science.gov (United States)

    Alfonta; Lital , Schultz; Peter G. , Zhang; Zhiwen

    2010-10-12

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate redox active amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with redox active amino acids using these orthogonal pairs.

  4. Site-specific incorporation of redox active amino acids into proteins

    Science.gov (United States)

    Alfonta, Lital; Schultz, Peter G.; Zhang, Zhiwen

    2009-02-24

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate redox active amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with redox active amino acids using these orthogonal pairs.

  5. Site-specific incorporation of redox active amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Alfonta, Lital [San Diego, CA; Schultz, Peter G [La Jolla, CA; Zhang, Zhiwen [San Diego, CA

    2012-02-14

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate redox active amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with redox active amino acids using these orthogonal pairs.

  6. Site-specific incorporation of redox active amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Alfonta; Lital (San Diego, CA), Schultz; Peter G. (La Jolla, CA), Zhang; Zhiwen (San Diego, CA)

    2010-10-12

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate redox active amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with redox active amino acids using these orthogonal pairs.

  7. Site-specific incorporation of redox active amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Alfonta, Lital (San Diego, CA); Schultz, Peter G. (La Jolla, CA); Zhang, Zhiwen (Austin, TX)

    2011-08-30

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate redox active amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with redox active amino acids using these orthogonal pairs.

  8. Lipase-catalyzed modification of rice bran oil to incorporate capric acid.

    Science.gov (United States)

    Jennings, B H; Akoh, C C

    2000-09-01

    Capric acid (C10:0) was incorporated into rice bran oil with an immobilized lipase from Rhizomucor miehei as the biocatalyst. Effects of incubation time, substrate mole ratio, enzyme load, and water addition on mole percent incorporation of C10:0 were studied. Transesterification was performed in an organic solvent, hexane, and under solvent-free condition. Pancreatic lipase-catalyzed sn-2 positional analysis and tocopherol analysis were performed before and after enzymatic modification. Products were analyzed by gas-liquid chromatography (GLC) for fatty acid composition. After 24 h of incubation in hexane, there was an average of 26.5 +/- 1.8 mol % incorporation of C10:0 into rice bran oil. The solvent-free reaction produced an average of 24.5 +/- 3.7 mol % capric acid. In general, as the enzyme load, substrate mole ratio, and incubation time increased, the mole percent of capric acid incorporation also increased. Time course reaction indicated C10:0 incorporation increased up to 27.0 mol % at 72 h, for the reaction in hexane, and up to 29.6 mol % at 12 h, for the solvent-free reaction. The highest C10:0 incorporations (53.1 and 43.2 mol %) for the mole ratio experiment occurred at a mole ratio of 1:8 for solvent and solvent-free reactions, respectively. The highest C10:0 incorporation (27.9 mol %) for the reaction in hexane occurred at 10% enzyme load, and the highest incorporation (34.4 mol %) for the solvent-free reaction occurred at 20% enzyme load. Incorporation of C10:0 into rice bran oil declined with the addition of increasing amounts of water after reaching 30.3 mol % at 2% water addition in hexane, and in the solvent-free reaction after reaching 35.9 mol %.

  9. Incorporation of polyunsaturated fatty acids into CT-26, a transplantable murine colonic adenocarcinoma.

    Science.gov (United States)

    Gaposchkin, D P; Zoeller, R A; Broitman, S A

    2000-02-01

    Previous studies in our laboratory have shown that marine oils, with high levels of eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic acids (DHA, 22:6n-3), inhibit the growth of CT-26, a murine colon carcinoma cell line, when implanted into the colons of male BALB/c mice. An in vitro model was developed to study the incorporation of polyunsaturated fatty acids (PUFA) into CT-26 cells in culture. PUFA-induced changes in the phospholipid fatty acid composition and the affinity with which different fatty acids enter the various phospholipid species and subspecies were examined. We found that supplementation of cultured CT-26 cells with either 50 microM linoleic acid (LIN, 18:2n-6), arachidonic acid (AA, 20:4n-6), EPA, or DHA significantly alters the fatty acid composition of CT-26 cells. Incorporation of these fatty acids resulted in decreased levels of monounsaturated fatty acids, while EPA and DHA also resulted in lower levels of AA. While significant elongation of both AA and EPA occurred, LIN remained relatively unmodified. Incorporation of radiolabeled fatty acids into different phospholipid species varied significantly. LIN was incorporated predominantly into phosphatidylcholine and had a much lower affinity for the ethanolamine phospholipids. DHA had a higher affinity for plasmenylethanolamine (1-O-alk-1'-enyl-2-acyl-sn-glycero-3-phosphoethanolamine) than the other fatty acids, while EPA had the highest affinity for phosphatidylethanol-amine (1,2-diacyl-sn-glycero-3-phosphoethanolamine). These results demonstrate that, in vitro, significant differences are seen between the various PUFA in CT-26 cells with respect to metabolism and distribution, and these may help to explain differences observed with respect to their effects on tumor growth and metastasis in the transplantable model.

  10. Efficient Production of Hydrogen from Decomposition of Formic Acid over Zeolite Incorporated Gold Nanoparticles

    DEFF Research Database (Denmark)

    Gallas-Hulin, Agata; Mielby, Jerrik Jørgen; Kegnæs, Søren

    2016-01-01

    Formic acid has a great potential as a safe and convenient source of hydrogen for sustainable chemical synthesis and renewable energy storage. Here, we report a heterogeneous gold nanoparticles catalyst for efficient production of hydrogen from vapor phase decomposition of formic acid using zeolite...... incorporated gold nanoparticles. The catalyst is prepared by pressure assisted impregnation and reduction (PAIR), which results in a uniform distribution of small gold nanoparticles that are incorporated into zeolite silicalite-1 crystals. Consequently, the incorporated nanoparticles exhibit increased...... sintering stability. Based on these results, we believe that incorporation of metal nanoparticles in zeolites may find use as highly active and selective heterogeneous catalysts for the production of hydrogen in future renewable energy applications....

  11. A general method for site-specific incorporation of unnatural amino acids into proteins

    Energy Technology Data Exchange (ETDEWEB)

    Noren, C.J.; Anthony-Cahill, S.J; Griffith, M.C.; Schultz, P.G. (Lawrence Berkeley Lab., CA (USA))

    1989-04-14

    A new method has been developed that makes it possible to site-specifically incorporate unnatural amino acids into proteins. Synthetic amino acids were incorporated into the enzyme {beta}-lactamase by the use of a chemically acylated suppressor transfer RNA that inserted the amino acid in response to a stop codon substituted for the codon encoding residue of interest. Peptide mapping localized the inserted amino acid to a single peptide, and enough enzyme could be generated for purification to homogeneity. The catalytic properties of several mutants at the conserved Phe{sup 66} were characterized. The ability to selectively replace amino acids in a protein with a wide variety of structural and electronic variants should provide a more detailed understanding of protein structure and function. 45 refs., 7 figs., 1 tab.

  12. Cisplatin-incorporated nanoparticles of poly(acrylic acid-co-methyl methacrylate copolymer

    Directory of Open Access Journals (Sweden)

    Lee KD

    2013-08-01

    Full Text Available Kyung Dong Lee,1,* Young-Il Jeong,2,* Da Hye Kim,3,4 Gyun-Taek Lim,2 Ki-Choon Choi5 1Department of Oriental Medicine Materials, Dongshin University, Naju, South Korea; 2Department of Polymer Engineering, Chonnam National University, Gwangju, South Korea; 3Faculty of Life and Environmental Science, Shimane University, Matsue, Japan; 4United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan; 5Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan, South Korea *These authors contributed equally to this work Background: Although cisplatin is extensively used in the clinical field, its intrinsic toxicity limits its clinical use. We investigated nanoparticle formations of poly(acrylic acid-co-methyl methacrylate (PAA-MMA incorporating cisplatin and their antitumor activity in vitro and in vivo. Methods: Cisplatin-incorporated nanoparticles were prepared through the ion-complex formation between acrylic acid and cisplatin. The anticancer activity of cisplatin-incorporated nanoparticles was assessed with CT26 colorectal carcinoma cells. Results: Cisplatin-incorporated nanoparticles have small particle sizes of less than 200 nm with spherical shapes. Drug content was increased according to the increase of the feeding amount of cisplatin and acrylic acid content in the copolymer. The higher acrylic acid content in the copolymer induced increase of particle size and decrease of zeta potential. Cisplatin-incorporated nanoparticles showed a similar growth-inhibitory effect against CT26 tumor cells in vitro. However, cisplatin-incorporated nanoparticles showed improved antitumor activity against an animal tumor xenograft model. Conclusion: We suggest that PAA-MMA nanoparticles incorporating cisplatin are promising carriers for an antitumor drug-delivery system. Keywords: cisplatin, nanoparticle, poly(acrylic acid-co-methyl methacrylate, ion complexes

  13. Incorporation of Amino Acids with Long-Chain Terminal Olefins into Proteins

    OpenAIRE

    Exner, Matthias P.; Sebastian Köhling; Julie Rivollier; Sandrine Gosling; Puneet Srivastava; Palyancheva, Zheni I; Piet Herdewijn; Marie-Pierre Heck; Jörg Rademann; Nediljko Budisa

    2016-01-01

    The increasing need for site-specific protein decorations that mimic natural posttranslational modifications requires access to a variety of noncanonical amino acids with moieties enabling bioorthogonal conjugation chemistry. Here we present the incorporation of long-chain olefinic amino acids into model proteins with rational variants of pyrrolysyl-tRNA synthetase (PylRS). Nε-heptenoyl lysine was incorporated for the first time using the known promiscuous variant PylRS(Y306A/Y384F), and Nε-p...

  14. Site specific incorporation of heavy atom-containing unnatural amino acids into proteins for structure determination

    Science.gov (United States)

    Xie, Jianming; Wang, Lei; Wu, Ning; Schultz, Peter G.

    2008-07-15

    Translation systems and other compositions including orthogonal aminoacyl tRNA-synthetases that preferentially charge an orthogonal tRNA with an iodinated or brominated amino acid are provided. Nucleic acids encoding such synthetases are also described, as are methods and kits for producing proteins including heavy atom-containing amino acids, e.g., brominated or iodinated amino acids. Methods of determining the structure of a protein, e.g., a protein into which a heavy atom has been site-specifically incorporated through use of an orthogonal tRNA/aminoacyl tRNA-synthetase pair, are also described.

  15. Synthesis of alanyl nucleobase amino acids and their incorporation into proteins.

    Science.gov (United States)

    Talukder, Poulami; Dedkova, Larisa M; Ellington, Andrew D; Yakovchuk, Petro; Lim, Jaebum; Anslyn, Eric V; Hecht, Sidney M

    2016-09-15

    Proteins which bind to nucleic acids and regulate their structure and functions are numerous and exceptionally important. Such proteins employ a variety of strategies for recognition of the relevant structural elements in their nucleic acid substrates, some of which have been shown to involve rather subtle interactions which might have been difficult to design from first principles. In the present study, we have explored the preparation of proteins containing unnatural amino acids having nucleobase side chains. In principle, the introduction of multiple nucleobase amino acids into the nucleic acid binding domain of a protein should enable these modified proteins to interact with their nucleic acid substrates using Watson-Crick and other base pairing interactions. We describe the synthesis of five alanyl nucleobase amino acids protected in a fashion which enabled their attachment to a suppressor tRNA, and their incorporation into each of two proteins with acceptable efficiencies. The nucleobases studied included cytosine, uracil, thymine, adenine and guanine, i.e. the major nucleobase constituents of DNA and RNA. Dihydrofolate reductase was chosen as one model protein to enable direct comparison of the facility of incorporation of the nucleobase amino acids with numerous other unnatural amino acids studied previously. The Klenow fragment of DNA polymerase I was chosen as a representative DNA binding protein whose mode of action has been studied in detail. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Orthogonal translation components for the in vivo incorporation of unnatural amino acids

    Science.gov (United States)

    Schultz, Peter G.; Xie, Jianming; Zeng, Huaqiang

    2012-07-10

    The invention relates to orthogonal pairs of tRNAs and aminoacyl-tRNA synthetases that can incorporate unnatural amino acids into proteins produced in eubacterial host cells such as E. coli, or in a eukaryotic host such as a yeast cell. The invention provides, for example but not limited to, novel orthogonal synthetases, methods for identifying and making the novel synthetases, methods for producing proteins containing unnatural amino acids, and translation systems.

  17. Orthogonal translation components for the in vivo incorporation of unnatural amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G.; Alfonta, Lital; Chittuluru, Johnathan R.; Deiters, Alexander; Groff, Dan; Summerer, Daniel; Tsao, Meng -Lin; Wang, Jiangyun; Wu, Ning; Xie, Jianming; Zeng, Huaqiang; Seyedsayamdost, Mohammad; Turner, James

    2015-08-11

    The invention relates to orthogonal pairs of tRNAs and aminoacyl-tRNA synthetase that can incorporate unnatural amino acid into proteins produced in eubacterial host cells such as E. coli, or in a eukaryotic host such as a yeast cell. The invention provides, for example but not limited to, novel orthogonal synthetases, methods for identifying and making the novel synthetases, methods for producing proteins containing unnatural amino acids, and translation systems.

  18. Orthogonal translation components for the in vivo incorporation of unnatural amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter G.; Xie, Jianming; Zeng, Huaqiang

    2012-07-10

    The invention relates to orthogonal pairs of tRNAs and aminoacyl-tRNA synthetases that can incorporate unnatural amino acids into proteins produced in eubacterial host cells such as E. coli, or in a eukaryotic host such as a yeast cell. The invention provides, for example but not limited to, novel orthogonal synthetases, methods for identifying and making the novel synthetases, methods for producing proteins containing unnatural amino acids, and translation systems.

  19. Incorporation of medium chain fatty acids into fish oil triglycerides by chemical and enzymatic inter esterification

    Energy Technology Data Exchange (ETDEWEB)

    Feltes, M. M. C.; Oliveira de Pilot, L.; Gomes Correira, F.; Grimaldi, R.; Mara Block, J.; Ninow, J. L.

    2009-07-01

    Structured triglycerides (STs) containing both medium chain fatty acids (MCFA) and polyunsaturated fatty acids (PUFA) in the same molecule offer nutritional and therapeutic benefits. The aim of this work was to establish the incorporation of MCFA into fish oil triglycerides (TAGs), while maintaining substantial levels of docosahexaenoic and eicosapentaenoic acids. The effects of different acyl donors (capric acid methyl ester/MeC10 or medium chain triglyceride/TCM) and of the catalyst (chemical or enzymatic) on the fatty acid composition of the reaction product were studied. The fatty acid composition of the fish oil TAG was modified after inter esterification to contain MCFA, and it depended on the catalyst and on the substrates. Thermo grams obtained by Differential Scanning Calorimetry (DSC) showed that inter esterification promoted noteworthy changes in the melting profile of the samples. STs of clinical nutrition interest containing both EPA and DHA obtained from fish oil along with MCFA were successfully produced. (Author) 70 refs.

  20. Amino acid incorporation into the protein of mitochondrial preparations from cerebral cortex and spinal cord.

    Science.gov (United States)

    Bachelard, H S

    1966-07-01

    1. Washed guinea-pig cerebral-cortex mitochondria incorporate [(14)C]leucine into their protein at a rate comparable with the rates reported for liver or heart mitochondria only if the mitochondria are separated from myelin and nerve endings by density-gradient centrifugation. 2. The non-mitochondrial components (myelin and nerve endings) of brain mitochondrial preparations incorporated [(14)C]leucine at a negligible rate. 3. The mitochondria do not require an exogenous supply of energy or a full supply of amino acids to support the process. 4. The incorporation rate was linear up to 2hr. aerobic incubation at 30 degrees and was inhibited by chloramphenicol, only slightly by actinomycin D and not by penicillin or pretreatment with ribonuclease. The observed incorporation is considered to be unlikely to be due to contaminating cytoplasmic ribosomes or bacteria. 5. The process was also studied in mitochondrial preparations from rabbit cerebral cortex and spinal cord.

  1. Incorporation of radioactive polyunsaturated fatty acids into liver and brain of developing rat.

    Science.gov (United States)

    Sinclair, A J

    1975-03-01

    The incorporation of radioactivity from orally administered linoleic acid-1-14C, linolenic acid-1-14C, arachidonic acid-3H8, and docosahexaenoic acid-14C into the liver and brain lipids of suckling rats was studied. In both tissues, 22 hr after dosing, 2 distinct levels of incorporation were observed: a low uptake (from 18:2-1-14C and 18:3-1-14C) and a high uptake (from 20:4-3H8 and 22:6-14C). In adult rats, the incorporation of radioactivity into brain lipids from 18:2-1-14C and 20:4-3H was considerably lower than the incorporation into the brains of the young rats. In the livers of the suckling rats, the activity from the 18 carbon acids was associated mostly with the triglyceride fraction, whereas the activity from the 20:4-3H8 and 22:6-14C was concentrated in the phospholipid fraction. In the brain lipids, the activity from the different fatty apid fatty acids, some of the activity in the 18:2-1-14C and 18:3-1-14C experiments was associated with 20 and 22 carbon polyunsaturated fatty acids; however, radioactivity from orally administered 20:4-3H8 and 22:6-14C was incorporated intact into the tissue phospholipid to a much greater extent compared with the incorporation of radioactivity into 20:4 and 22:6 in the experiments where 18:2-1-14C and 18:3-1-14C, respectively, were administered. Possible reasons for these differences are discussed. Rat milk contains a wide spectrum of polyunsaturated fatty acids, including linoleate, linolenate, arachidonate, and docosahexaenoate. During the suckling period in the rat, there is a rapid deposition of 20:4 and 22:6 in the brain. The results of the present experiments suggested that dietary 20:4 and 22:6 were important sources of brain 20:4 and 22:6 in the developing rat.

  2. Incorporation of nitrogen from N2 fixation into amino acids of zooplankton

    DEFF Research Database (Denmark)

    Loick-Wilde, Natalie; Dutz, Jörg; Miltner, Anja;

    2012-01-01

    quantified the direct incorporation of 15N tracer from N2-fixing N. spumigena (diazotroph nitrogen) and ammonium-utilizing R. salina into the amino acid nitrogen (AA-N) of zooplankton using complementary gas chromatography– combustion–isotope ratio mass spectrometry, gas chromatography–mass spectrometry...... consistently low in E. affinis when exposed to N. spumigena, suggesting that these animals were reluctant to feed on N. spumigena. Essential isoleucine received most of the diazotroph nitrogen in field zooplankton, while nonessential amino acids received most 15N tracer in E. affinis. N. spumigena was clearly...... an important amino acid nitrogen source for Baltic Sea zooplankton...

  3. Amino acid isotope incorporation and enrichment factors in Pacific bluefin tuna, Thunnus orientalis.

    Directory of Open Access Journals (Sweden)

    Christina J Bradley

    Full Text Available Compound specific isotopic analysis (CSIA of amino acids has received increasing attention in ecological studies in recent years due to its ability to evaluate trophic positions and elucidate baseline nutrient sources. However, the incorporation rates of individual amino acids into protein and specific trophic discrimination factors (TDFs are largely unknown, limiting the application of CSIA to trophic studies. We determined nitrogen turnover rates of individual amino acids from a long-term (up to 1054 days laboratory experiment using captive Pacific bluefin tuna, Thunnus orientalis (PBFT, a large endothermic pelagic fish fed a controlled diet. Small PBFT (white muscle δ(15N∼11.5‰ were collected in San Diego, CA and transported to the Tuna Research and Conservation Center (TRCC where they were fed a controlled diet with high δ(15N values relative to PBFT white muscle (diet δ(15N∼13.9‰. Half-lives of trophic and source amino acids ranged from 28.6 to 305.4 days and 67.5 to 136.2 days, respectively. The TDF for the weighted mean values of amino acids was 3.0 ‰, ranging from 2.2 to 15.8 ‰ for individual combinations of 6 trophic and 5 source amino acids. Changes in the δ(15N values of amino acids across trophic levels are the underlying drivers of the trophic (15N enrichment. Nearly all amino acid δ(15N values in this experiment changed exponentially and could be described by a single compartment model. Significant differences in the rate of (15N incorporation were found for source and trophic amino acids both within and between these groups. Varying half-lives of individual amino acids can be applied to migratory organisms as isotopic clocks, determining the length of time an individual has spent in a new environment. These results greatly enhance the ability to interpret compound specific isotope analyses in trophic studies.

  4. Rice straw incorporated just before soil flooding increases acetic acid formation and decreases available nitrogen

    Directory of Open Access Journals (Sweden)

    Ronaldir Knoblauch

    2014-02-01

    Full Text Available Incorporation of rice straw into the soil just before flooding for water-seeded rice can immobilize mineral nitrogen (N and lead to the production of acetic acid harmful to the rice seedlings, which negatively affects grain yield. This study aimed to evaluate the formation of organic acids and variation in pH and to quantify the mineral N concentration in the soil as a function of different times of incorporation of rice straw or of ashes from burning the straw before flooding. The experiment was carried out in a greenhouse using an Inceptisol (Typic Haplaquept soil. The treatments were as follows: control (no straw or ash; incorporation of ashes from previous straw burning; rice straw incorporated to drained soil 60 days before flooding; straw incorporated 30 days before flooding; straw incorporated 15 days before flooding and straw incorporated on the day of flooding. Experimental units were plastic buckets with 6.0 kg of soil. The buckets remained flooded throughout the trial period without rice plants. Soil samples were collected every seven days, beginning one day before flooding until the 13th week of flooding for determination of mineral N- ammonium (NH4+ and nitrate (NO3-. Soil solution pH and concentration of organic acids (acetic, propionic and butyric were determined. All NO3- there was before flooding was lost in approximately two weeks of flooding, in all treatments. There was sigmoidal behavior for NH4+ formation in all treatments, i.e., ammonium ion concentration began to rise shortly after soil flooding, slightly decreased and then went up again. On the 91st day of flooding, the NH4+ concentrations in soil was 56 mg kg-1 in the control treatment, 72 mg kg-1 for the 60-day treatment, 73 mg kg-1 for the 30-day treatment and 53 mg kg-1 for the ash incorporation treatment. These ammonium concentrations correspond to 84, 108, 110 and 80 kg ha-1 of N-NH4+, respectively. When the straw was incorporated on the day of flooding or 15 days

  5. Lipase inhibitor orlistat decreases incorporation of eicosapentaenoic and docosahexaenoic acids in rat tissues.

    Science.gov (United States)

    Cruz-Hernandez, Cristina; Oliveira, Manuel; Pescia, Grégory; Moulin, Julie; Masserey-Elmelegy, Isabelle; Dionisi, Fabiola; Destaillats, Frédéric

    2010-02-01

    Orlistat is a gastric and pancreatic lipases inhibitor that is often prescribed to obese subjects. Orlistat has been shown to decrease the absorption of biologically important lipophilic micronutrients such as liposoluble vitamins. We hypothesized that long-term administration of orlistat may lower the incorporation of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) in blood lipids and tissues. This hypothesis was tested in rats fed a diet supplemented with fish oil as a source of n-3 LC-PUFA. Male Wistar rats (n = 18) were divided into 3 groups and fed experimental high-fat diets containing fish oil (control diet) or fish oil plus orlistat (200 and 400 mg/kg of diet) over the course of 3 weeks. Fat absorption and the level of eicosapentaenoic acid (EPA) and docosahexaenoic acid, among other fatty acids, in red blood cells, plasma, liver, and spleen, were measured at the end of the experimental period. The results show that at 200 mg and 400 mg/kg of diet orlistat lowers fat absorption by 9% (P = .008) and 54% (P = .008). Orlistat given at the higher level induced a reduction of the incorporation of EPA in red blood cell (-45%; P = .006) and in plasma (-34%; P = .026) compared to the control group. Our results confirmed that administration of orlistat reduces incorporation of n-3 LC-PUFA in blood lipids and tissues in a rat model.

  6. Non-standard amino acid incorporation into proteins using Escherichia coli cell-free protein synthesis

    Directory of Open Access Journals (Sweden)

    Seok Hoon eHong

    2014-06-01

    Full Text Available Incorporating non-standard amino acids (NSAAs into proteins enables new chemical properties, new structures, and new functions. In recent years, improvements in cell-free protein synthesis (CFPS systems have opened the way to accurate and efficient incorporation of NSAAs into proteins. The driving force behind this development has been three-fold. First, a technical renaissance has enabled high-yielding (>1 g/L and long-lasting (>10 h in batch operation CFPS in systems derived from Escherichia coli. Second, the efficiency of orthogonal translation systems has improved. Third, the open nature of the CFPS platform has brought about an unprecedented level of control and freedom of design. Here, we review recent developments in CFPS platforms designed to precisely incorporate NSAAs. In the coming years, we anticipate that CFPS systems will impact efforts to elucidate structure/function relationships of proteins and to make biomaterials and sequence-defined biopolymers for medical and industrial applications.

  7. Characterization of gelation process and drug release profile of thermosensitive liquid lecithin/poloxamer 407 based gels as carriers for percutaneous delivery of ibuprofen.

    Science.gov (United States)

    Djekic, Ljiljana; Krajisnik, Danina; Martinovic, Martina; Djordjevic, Dragana; Primorac, Marija

    2015-07-25

    Suitability of liquid lecithin (i.e., solution of lecithin in soy bean oil with ∼ 60% w/w of phospholipids) for formation of gels, upon addition of water solution of poloxamer 407, was investigated, and formulated systems were evaluated as carriers for percutaneous delivery of ibuprofen. Formulation study of pseudo-ternary system liquid lecithin/poloxamer 407/water at constant liquid lecithin/poloxamer 407 mass ratio (2.0) revealed that minimum concentrations of liquid lecithin and poloxamer 407 required for formation of gel like systems were 15.75% w/w and 13.13% w/w, respectively, while the maximum content of water was 60.62% w/w. The systems comprising water concentrations in a range from 55 to 60.62% w/w were soft semisolids suitable for topical application, and they were selected for physicochemical and biopharmaceutical evaluation. Analysis of conductivity results and light microscopy examination revealed that investigated systems were water dilutable dispersions of spherical oligolamellar associates of phospholipids and triglyceride molecules in the copolymer water solution. Rheological behavior evaluation results indicated that the investigated gels were thermosensitive shear thinning systems. Ibuprofen (5% w/w) was incorporated by dispersing into the previously prepared carriers. Drug-loaded systems were physically stable at storage temperature from 5 ± 3°C to 40 ± 2°C, for 30 days. In vitro ibuprofen release was in accordance with the Higuchi model (rH>0.95) and sustained for 12h. The obtained results implicated that formulated LLPBGs, optimized regarding drug release and organoleptic properties, represent promising carriers for sustained percutaneous drug delivery of poorly soluble drugs. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Cells Attachment Property of PVA Hydrogel Nanofibers Incorporating Hyaluronic Acid for Tissue Engineering

    OpenAIRE

    2011-01-01

    In this work, we report the fabrication and cell affinity studies of the poly(vinyl alcohol) (PVA)/hyaluronic acid (HA) cross-linked nanofibers via electrospinning and post cross-linking. FT-IR and TGA analysis demonstrate that HA is not influenced by acid environment such as HCl vapor during cross-linking, and well incorporated into PVA nanofibers. Swelling behavior and cell adhesion of the PVA/HA hydrogel nanofibers are investigated and compared with pure PVA hydrogel nanofibers. It is expe...

  9. Effect of Hyaluronic Acid Incorporation Method on the Stability and Biological Properties of Polyurethane-Hyaluronic Acid Biomaterials

    Science.gov (United States)

    Ruiz, Amaliris; Rathnam, Kashmila R.; Masters, Kristyn S.

    2014-01-01

    The high failure rate of small diameter vascular grafts continues to drive the development of new materials and modification strategies that address this clinical problem, with biomolecule incorporation typically achieved via surface-based modification of various biomaterials. In this work, we examined whether the method of biomolecule incorporation (i.e., bulk vs. surface modification) into a polyurethane (PU) polymer impacted biomaterial performance in the context of vascular applications. Specifically, hyaluronic acid (HA) was incorporated into a poly(ether urethane) via bulk copolymerization or covalent surface tethering, and the resulting PU-HA materials characterized with respect to both physical and biological properties. Modification of PU with HA by either surface or bulk methods yielded materials that, when tested under static conditions, possessed no significant differences in their ability to resist protein adsorption, platelet adhesion, and bacterial adhesion, while supporting endothelial cell culture. However, only bulk-modified PU-HA materials were able to fully retain these characteristics following material exposure to flow, demonstrating a superior ability to retain the incorporated HA and minimize enzymatic degradation, protein adsorption, platelet adhesion, and bacterial adhesion. Thus, despite bulk methods rarely being implemented in the context of biomolecule attachment, these results demonstrate improved performance of PU-HA upon bulk, rather than surface, incorporation of HA. Although explored only in the context of PU-HA, the findings revealed by these experiments have broader implications for the design and evaluation of vascular graft modification strategies. PMID:24276670

  10. Poly(lactic-co-glycolic acid) matrix incorporated with nisin as a novel antimicrobial biomaterial.

    Science.gov (United States)

    Correia, Rafaela Coelho; Jozala, Angela Faustino; Martins, Kelly Fernanda; Penna, Thereza Christina Vessoni; Duek, Eliana Aparecida de Rezende; Rangel-Yagui, Carlota de Oliveira; Lopes, André Moreni

    2015-04-01

    The use of poly(lactic-co-glycolic acid) (PLGA) matrix as a biomolecule carrier has been receiving great attention due to its potential therapeutic application. In this context, we investigated the PLGA matrix capacity to incorporate nisin, an antimicrobial peptide capable of inhibiting the growth of Gram-positive bacteria and bacterial spores germination. Nisin-incorporated PLGA matrices were evaluated based on the inhibitory effect against the nisin-bioindicator Lactobacillus sakei. Additionally, the PLGA-nisin matrix stability over an 8-months period was investigated, as well as the nisin release profile. For the incorporation conditions, we observed that a 5 h incorporation time, at 30 °C, with 250 μg/mL nisin solution in PBS buffer pH 4.5, resulted in the highest inhibitory activity of 2.70 logAU/mL. The PLGA-nisin matrix was found to be relatively stable and showed sustained drug delivery, with continuous release of nisin for 2 weeks. Therefore, PLGA-nisin matrix is could be used as a novel antimicrobial delivery system and an alternative to antibiotics incorporated into PLGA matrices.

  11. Polyunsaturated fatty acids incorporation into cardiolipin in H9c2 cardiac myoblast.

    Science.gov (United States)

    Ting, Hsiu-Chi; Chao, Yu-Jen; Hsu, Yuan-Hao Howard

    2015-07-01

    Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), known as ω-3 polyunsaturated fatty acid (PUFA), are common nutrients in daily food intake and have been shown to prevent cardiovascular disease and improve cardiac functions. Cardiolipin is a mitochondrial phospholipid necessary for maintaining physiological function of mitochondria. Several studies have indicated that the cardiolipin acyl chain compositions affect the function of cardiolipin and mitochondria. Here, we investigated the structural changes of cardiolipin after DHA and EPA supplementation and compared them to arachidonic acid (AA) treatment. H9c2 cardiac myoblast was used as a cell model, and cardiolipin species was monitored and identified via LC-MS and MS/MS. Our results showed distinct mass envelopes of cardiolipin with the same carbon number but different double bonds in mass spectrum. There were 116 cardiolipin species with 36 distinct mass in 6 mass envelopes identified by MS/MS. Three days of PUFA treatment resulted in decreases of low-molecular-weight cardiolipin and increases of high-molecular-weight cardiolipin, suggesting the incorporation of exogenous DHA, EPA and AA into mitochondrial cardiolipin. PUFA incorporation was further verified by MS/MS analysis. More importantly, we found that DHA supplementation elevated the percent content of less unsaturated cardiolipin species and highly unsaturated cardiolipin species, containing ω-3 fatty acyl chains, indicating a ω-3 fatty acid incorporation mechanism with peroxidation protection. Our results indicate that PUFA supplementation differentially perturbed the fatty acyl chain compositions in the mitochondrial cardiolipin in the H9c2 cardiac myoblast, suggesting that mitochondrial membrane and the function of mitochondria are susceptible to exogenous lipid species.

  12. Incorporation of noncanonical amino acids into Rosetta and use in computational protein-peptide interface design.

    Directory of Open Access Journals (Sweden)

    P Douglas Renfrew

    Full Text Available Noncanonical amino acids (NCAAs can be used in a variety of protein design contexts. For example, they can be used in place of the canonical amino acids (CAAs to improve the biophysical properties of peptides that target protein interfaces. We describe the incorporation of 114 NCAAs into the protein-modeling suite Rosetta. We describe our methods for building backbone dependent rotamer libraries and the parameterization and construction of a scoring function that can be used to score NCAA containing peptides and proteins. We validate these additions to Rosetta and our NCAA-rotamer libraries by showing that we can improve the binding of a calpastatin derived peptides to calpain-1 by substituting NCAAs for native amino acids using Rosetta. Rosetta (executables and source, auxiliary scripts and code, and documentation can be found at (http://www.rosettacommons.org/.

  13. Rationally evolving tRNAPyl for efficient incorporation of noncanonical amino acids.

    Science.gov (United States)

    Fan, Chenguang; Xiong, Hai; Reynolds, Noah M; Söll, Dieter

    2015-12-15

    Genetic encoding of noncanonical amino acids (ncAAs) into proteins is a powerful approach to study protein functions. Pyrrolysyl-tRNA synthetase (PylRS), a polyspecific aminoacyl-tRNA synthetase in wide use, has facilitated incorporation of a large number of different ncAAs into proteins to date. To make this process more efficient, we rationally evolved tRNA(Pyl) to create tRNA(Pyl-opt) with six nucleotide changes. This improved tRNA was tested as substrate for wild-type PylRS as well as three characterized PylRS variants (N(ϵ)-acetyllysyl-tRNA synthetase [AcKRS], 3-iodo-phenylalanyl-tRNA synthetase [IFRS], a broad specific PylRS variant [PylRS-AA]) to incorporate ncAAs at UAG codons in super-folder green fluorescence protein (sfGFP). tRNA(Pyl-opt) facilitated a 5-fold increase in AcK incorporation into two positions of sfGFP simultaneously. In addition, AcK incorporation into two target proteins (Escherichia coli malate dehydrogenase and human histone H3) caused homogenous acetylation at multiple lysine residues in high yield. Using tRNA(Pyl-opt) with PylRS and various PylRS variants facilitated efficient incorporation of six other ncAAs into sfGFP. Kinetic analyses revealed that the mutations in tRNA(Pyl-opt) had no significant effect on the catalytic efficiency and substrate binding of PylRS enzymes. Thus tRNA(Pyl-opt) should be an excellent replacement of wild-type tRNA(Pyl) for future ncAA incorporation by PylRS enzymes.

  14. Rationally evolving tRNAPyl for efficient incorporation of noncanonical amino acids

    Science.gov (United States)

    Fan, Chenguang; Xiong, Hai; Reynolds, Noah M.; Söll, Dieter

    2015-01-01

    Genetic encoding of noncanonical amino acids (ncAAs) into proteins is a powerful approach to study protein functions. Pyrrolysyl-tRNA synthetase (PylRS), a polyspecific aminoacyl-tRNA synthetase in wide use, has facilitated incorporation of a large number of different ncAAs into proteins to date. To make this process more efficient, we rationally evolved tRNAPyl to create tRNAPyl-opt with six nucleotide changes. This improved tRNA was tested as substrate for wild-type PylRS as well as three characterized PylRS variants (Nϵ-acetyllysyl-tRNA synthetase [AcKRS], 3-iodo-phenylalanyl-tRNA synthetase [IFRS], a broad specific PylRS variant [PylRS-AA]) to incorporate ncAAs at UAG codons in super-folder green fluorescence protein (sfGFP). tRNAPyl-opt facilitated a 5-fold increase in AcK incorporation into two positions of sfGFP simultaneously. In addition, AcK incorporation into two target proteins (Escherichia coli malate dehydrogenase and human histone H3) caused homogenous acetylation at multiple lysine residues in high yield. Using tRNAPyl-opt with PylRS and various PylRS variants facilitated efficient incorporation of six other ncAAs into sfGFP. Kinetic analyses revealed that the mutations in tRNAPyl-opt had no significant effect on the catalytic efficiency and substrate binding of PylRS enzymes. Thus tRNAPyl-opt should be an excellent replacement of wild-type tRNAPyl for future ncAA incorporation by PylRS enzymes. PMID:26250114

  15. Incorporation of a dietary omega 3 fatty acid impairs murine macrophage responses to Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Diana L Bonilla

    Full Text Available BACKGROUND: Beside their health benefits, dietary omega 3 polyunsaturated fatty acids (n-3 PUFA might impair host resistance to Mycobacterium tuberculosis (Mtb by creating an immunosuppressive environment. We hypothesized that incorporation of n-3 PUFA suppresses activation of macrophage antimycobacterial responses and favors bacterial growth, in part, by modulating the IFNgamma-mediated signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: Murine macrophage-like J774A.1 cells were incubated with bovine serum albumin (BSA-conjugated docosahexaenoic acid (DHA; 22:6n-3 or BSA alone, activated with recombinant IFNgamma, and infected with a virulent strain (H37Rv of M. tuberculosis. The fatty acid composition of macrophage membranes was modified significantly by DHA treatment. DHA-treated macrophages were less effective in controlling intracellular mycobacteria and showed impaired oxidative metabolism and reduced phagolysosome maturation. Incorporation of DHA resulted in defective macrophage activation, as characterized by reduced production of pro-inflammatory cytokines (TNFalpha, IL-6 and MCP-1, and lower expression of co-stimulatory molecules (CD40 and CD86. DHA treatment impaired STAT1 phosphorylation and colocalization of the IFNgamma receptor with lipid rafts, without affecting surface expression of IFNgamma receptor. CONCLUSIONS/SIGNIFICANCE: We conclude that DHA reduces the ability of J774A.1 cells to control M. tuberculosis in response to activation by IFNgamma, by modulation of IFNgamma receptor signaling and function, suggesting that n-3 PUFA-enriched diets may have a detrimental effect on host immunity to tuberculosis.

  16. Arachidonic acid incorporation and turnover is decreased in sympathetically denervated rat heart.

    Science.gov (United States)

    Patrick, Casey B; McHowat, Jane; Rosenberger, Thad A; Rapoport, Stanley I; Murphy, Eric J

    2005-06-01

    Heart sympathetic denervation can accompany Parkinson's disease, but the effect of this denervation on cardiac lipid-mediated signaling is unknown. To address this issue, rats were sympathetically denervated with 6-hydroxydopamine (6-OHDA, 50 mg/kg ip) and infused with 170 muCi/kg of either [1-(14)C]palmitic acid ([1-(14)C]16:0) or [1-(14)C]arachidonic acid ([1-(14)C]20:4 n-6), and kinetic parameters were assessed using a steady-state radiotracer model. Heart norepinephrine and epinephrine levels were decreased 82 and 85%, respectively, in denervated rats, and this correlated with a 34% reduction in weight gain in treated rats. Fatty acid tracer uptake was not significantly different between groups for either tracer, although the dilution coefficient lambda was increased in [1-(14)C]20:4 n-6-infused rats, which indicates that less 20:4 n-6 was recycled in denervated rats. In [1-(14)C]16:0-infused rats, incorporation rate and turnover values of 16:0 in stable lipid compartments were unchanged, which is indicative of preservation of beta-oxidation. In [1-(14)C]20:4 n-6-infused rats, there were dramatic reductions in incorporation rate (60-84%) and turnover value (56-85%) in denervated rats that were dependent upon the lipid compartment. In addition, phospholipase A(2) activity was reduced 40% in treated rats, which is consistent with the reduction observed in 20:4 n-6 turnover. These results demonstrate marked reductions in 20:4 n-6 incorporation rate and turnover in sympathetic denervated rats and thereby suggest an effect on lipid-mediated signal transduction mediated by a reduction in phospholipase A(2) activity.

  17. Asymmetric synthesis of vinylogous β-amino acids and their incorporation into mixed backbone oligomers.

    Science.gov (United States)

    Wu, Hao; An, Hongchan; Mo, Shuting Cynthia; Kodadek, Thomas

    2017-03-27

    Chiral vinylogous β-amino acids (VBAA) were synthesized using enantioselective Mannich reactions of aldehydes with in situ generated N-carbamoyl imines followed by a Horner-Wadsworth-Emmons reaction. The efficiency with which these units could be incorporated into oligomers with different moieties on the C- and N-terminal sides was established, as was the feasibility of sequencing oligomers containing VBAAs by tandem mass spectrometry. The data show that VBAAs will be useful building blocks for the construction of combinatorial libraries of peptidomimetic compounds.

  18. Localization of GroEL determined by in vivo incorporation of a fluorescent amino acid

    DEFF Research Database (Denmark)

    Charbon, Godefroid; Wang, Jiangyun; Brustad, Eric

    2011-01-01

    Escherichia coli cells, indicated colocalization with the cell division protein FtsZ at the cleavage furrow, while a second E. coli study of fixed cells indicated more even distribution throughout the cytoplasm. Here, for the first time, we have examined the spatial distribution of GroEL in living cells using......The molecular chaperone GroEL is required for bacterial growth under all conditions, mediating folding assistance, via its central cavity, to a diverse set of cytosolic proteins; yet the subcellular localization of GroEL remains unresolved. An earlier study, using antibody probing of fixed...... incorporation of a fluorescent unnatural amino acid into the chaperone. Fluorescence microscopy indicated that GroEL is diffusely distributed, both under normal and stress conditions. Importantly, the present procedure uses a small, fluorescent unnatural amino acid to visualize GroEL in vivo, avoiding...

  19. Starch-based Antimicrobial Films Incorporated with Lauric Acid and Chitosan

    Science.gov (United States)

    Salleh, E.; Muhamad, I. I.

    2010-03-01

    Antimicrobial (AM) packaging is one of the most promising active packaging systems. Starch-based film is considered an economical material for antimicrobial packaging. This study aimed at the development of food packaging based on wheat starch incorporated with lauric acid and chitosan as antimicrobial agents. The purpose is to restrain or inhibit the growth of spoilage and/or pathogenic microorganisms that are contaminating foods. The antimicrobial effect was tested on B. substilis and E. coli. Inhibition of bacterial growth was examined using two methods, i.e. zone of inhibition test on solid media and liquid culture test (optical density measurements). The control and AM films (incorporated with chitosan and lauric acid) were produced by casting method. From the observations, AM films exhibited inhibitory zones. Interestingly, a wide clear zone on solid media was observed for B. substilis growth inhibition whereas inhibition for E. coli was not as effective as B. substilis. From the liquid culture test, the AM films clearly demonstrated a better inhibition against B. substilis than E. coli.

  20. Physicochemical and Antibacterial Properties of Carrageenan and Gelatine Hydrosols and Hydrogels Incorporated with Acidic Electrolyzed Water

    Directory of Open Access Journals (Sweden)

    Ewa Brychcy

    2015-12-01

    Full Text Available The article focuses on investigation of the effects of usage of acidic electrolyzed water (AEW with different sodium chloride concentration (0.001%, 0.01%, and 0.1% for the preparation of carrageenan and gelatine hydrosols and hydrogels. To determine physiochemical properties of hydrosols, the pH, oxidation-reduction potential (ORP, available chloride concentration (ACC and rheological parameters such us gelation and flow temperatures were measured. The samples were also characterized using Fourier transform infrared spectroscopy (FT IR and texture profile analysis (TPA. Additionally, the article contains an analysis of antibacterial activity of carrageenan and gelatine hydrosols incorporated with acidic electrolyzed water, against Staphylococcus aureus and Escherichia coli. The FT IR spectra demonstrated that the structure of gelatine and carrageenan are not significantly affected by electrolyzed NaCl solution components. Furthermore, TPA analysis showed that the use of AEW did not cause undesirable changes in hydrogels layer. The microbiological analysis confirmed inhibition of bacterial growth by hydrosols to about 2.10 log reduction. The results showed that the range of reduction of microorganisms depends on the type AEW used. This might be explained by the fact that the lowest pH and the highest ACC values of hydrosols were obtained for samples with the longest period of exposure to electrolysis (10 min and the highest amount of NaCl (0.1% w/v. These results suggest that hydrogels and hydrosols incorporated with AEW may be used for food preservation.

  1. Metabolism of red-cell lipids I. Incorporation in vitro of fatty acids into phospholipids from mature erythrocytes

    NARCIS (Netherlands)

    Mulder, E.; Deenen, L.L.M. van

    1965-01-01

    Erythrocytes freed from leucocytes and reticulocytes were demonstrated to incorporate fatty acids into their phosphoglycerides. This ability was decreased in the order rat, rabbit, man, ox and sheep. Lysis of the cells caused an increase of the rate of incorporation thereby abolishing the difference

  2. Red-Shifted Aequorin Variants Incorporating Non-Canonical Amino Acids: Applications in In Vivo Imaging.

    Directory of Open Access Journals (Sweden)

    Kristen M Grinstead

    Full Text Available The increased importance of in vivo diagnostics has posed new demands for imaging technologies. In that regard, there is a need for imaging molecules capable of expanding the applications of current state-of-the-art imaging in vivo diagnostics. To that end, there is a desire for new reporter molecules capable of providing strong signals, are non-toxic, and can be tailored to diagnose or monitor the progression of a number of diseases. Aequorin is a non-toxic photoprotein that can be used as a sensitive marker for bioluminescence in vivo imaging. The sensitivity of aequorin is due to the fact that bioluminescence is a rare phenomenon in nature and, therefore, it does not suffer from autofluorescence, which contributes to background emission. Emission of bioluminescence in the blue-region of the spectrum by aequorin only occurs when calcium, and its luciferin coelenterazine, are bound to the protein and trigger a biochemical reaction that results in light generation. It is this reaction that endows aequorin with unique characteristics, making it ideally suited for a number of applications in bioanalysis and imaging. Herein we report the site-specific incorporation of non-canonical or non-natural amino acids and several coelenterazine analogues, resulting in a catalog of 72 cysteine-free, aequorin variants which expand the potential applications of these photoproteins by providing several red-shifted mutants better suited to use in vivo. In vivo studies in mouse models using the transparent tissue of the eye confirmed the activity of the aequorin variants incorporating L-4-iodophehylalanine and L-4-methoxyphenylalanine after injection into the eye and topical addition of coelenterazine. The signal also remained localized within the eye. This is the first time that aequorin variants incorporating non-canonical amino acids have shown to be active in vivo and useful as reporters in bioluminescence imaging.

  3. Platinum-Incorporating Poly(N-vinylpyrrolidone)-poly(aspartic acid) Pseudoblock Copolymer Nanoparticles for Drug Delivery.

    Science.gov (United States)

    Yao, Xikuang; Xie, Chen; Chen, Weizhi; Yang, Chenchen; Wu, Wei; Jiang, Xiqun

    2015-07-13

    Cisplatin-incorporating pseudoblock copolymer nanoparticles with high drug loading efficiency (ca. 50%) were prepared built on host-guest inclusion complexation between β-cyclodextrin end-capped poly(N-vinylpyrrolidone) block and admantyl end-capped poly(aspartic acid) block, followed by the coordination between cisplatin and carboxyl groups in poly(aspartic acid). The host-guest interaction between the two polymer blocks was examined by two-dimensional nuclear overhauser effect spectroscopy. The size and morphology of nanoparticles formed were characterized by dynamic light scattering, zeta potential, transmission electron microscopy, and atomic force microscopy. The size control of nanoparticles was carried out by varying the ratio of poly(N-vinylpyrrolidone) to poly(aspartic acid). The nanoparticles were stable in the aqueous medium with different pH values but disintegrated in the medium containing Cl(-) ions. The in vitro and in vivo antitumor effects of cisplatin-loaded nanoparticles were evaluated. The biodistribution of the nanoparticles in vivo was studied by noninvasive near-infrared fluorescence imaging and ion-coupled plasma mass spectrometry. It was found that cisplatin-loaded nanoparticles could effectively accumulate in the tumor site and exhibited significant superior in vivo antitumor activity to the commercially available free cisplatin by combining the tumor volume, body weight, and survival rate measurements.

  4. Doxycycline and hydroxypropyl-β-cyclodextrin complex in poloxamer thermal sensitive hydrogel for ophthalmic delivery

    Directory of Open Access Journals (Sweden)

    Zi-xin He

    2011-12-01

    Full Text Available The present study aimed to prepare a chemically and physically stable formulation of doxycycline (Doxy in an in situ thermally sensitive hydrogel for ophthalmic delivery. An inclusion complex of Doxy and hydroxypropyl-β-cyclodextrin (HP-β-CD was first developed to increase the stability of Doxy in aqueous solution. The physical characteristics (phase solubility profiles, thermal analysis, X-ray powder diffractograms and infrared spectra of the Doxy-HP-β-CD inclusion complex indicated the formation of a stable 1:1 complex. Poloxamers P407 (16–22% and P188 (0–5% were mixed to obtain a hydrogel with an appropriate gelation temperature for opthalmic use. Formulation of the inclusion complex in the poloxamer hydrogel exhibited a suitable gelation temperature (33.3 °C after dilution with simulated tear fluid (Gel:STF=40:7, v/v. The release of Doxy from the poloxamer hydrogel followed a zero order equation suggesting it occurs through corrosion of the poloxamer hydrogel. Stability studies demonstrated that the inclusion of Doxy by HP-β-CD markedly improved its stability in aqueous solution both at 8 and 40 °C. This formulation of a doxycycline-HP-β-CD inclusion complex in an in situ thermally sensitive poloxamer hydrogel represents a potentially effective ophthalmic Doxy delivery system.

  5. Direct incorporation of fatty acids into microbial phospholipids in soils: Position-specific labeling tells the story

    Science.gov (United States)

    Dippold, Michaela A.; Kuzyakov, Yakov

    2016-02-01

    Fatty acids have been used as plant and microbial biomarkers, and knowledge about their transformation pathways in soils and sediments is crucial for interpreting fatty acid signatures, especially because the formation, recycling and decomposition processes are concurrent. We analyzed the incorporation of free fatty acids into microbial fatty acids in soil by coupling position-specific 13C labeling with compound-specific 13C analysis. Position-specifically and uniformly 13C labeled palmitate were applied in an agricultural Luvisol. Pathways of fatty acids were traced by analyzing microbial utilization of 13C from individual molecule positions of palmitate and their incorporation into phospholipid fatty acids (PLFA). The fate of palmitate 13C in the soil was characterized by the main pathways of microbial fatty acid metabolism: Odd positions (C-1) were preferentially oxidized to CO2 in the citric acid cycle, whereas even positions (C-2) were preferentially incorporated into microbial biomass. This pattern is a result of palmitate cleavage to acetyl-CoA and its further use in the main pathways of C metabolism. We observed a direct, intact incorporation of more than 4% of the added palmitate into the PLFA of microbial cell membranes, indicating the important role of palmitate as direct precursor for microbial fatty acids. Palmitate 13C was incorporated into PLFA as intact alkyl chain, i.e. the C backbone of palmitate was not cleaved, but palmitate was incorporated either intact or modified (e.g. desaturated, elongated or branched) according to the fatty acid demand of the microbial community. These modifications of the incorporated palmitate increased with time. Future PLFA studies must therefore consider the recycling of existing plant and microbial-derived fatty acids. This study demonstrates the intact uptake and recycling of free fatty acids such as palmitate in soils, as well as the high turnover and transformation of cellular PLFA. Knowledge about the intact

  6. Incorporation of medium chain fatty acids into fish oil triglycerides by chemical and enzymatic interesterification

    Directory of Open Access Journals (Sweden)

    2009-06-01

    Full Text Available Structured triglycerides (STs containing both medium-chain fatty acids (MCFA and polyunsaturated fatty acids (PUFA in the same molecule offer nutritional and therapeutic benefits. The aim of this work was to establish the incorporation of MCFA into fish oil triglycerides (TAGs, while maintaining substantial levels of docosahexaenoic and eicosapentaenoic acids. The effects of different acyl donors (capric acid methyl ester/MeC10 or medium chain triglyceride/TCM and of the catalyst (chemical or enzymatic on the fatty acid composition of the reaction product were studied. The fatty acid composition of the fish oil TAG was modified after interesterification to contain MCFA, and it depended on the catalyst and on the substrates. Thermograms obtained by Differential Scanning Calorimetry (DSC showed that interesterification promoted noteworthy changes in the melting profile of the samples. STs of clinical nutrition interest containing both EPA and DHA obtained from fish oil along with MCFA were successfully produced.

    Triglicéridos estructurados (SL conteniendo ácidos grasos de cadena media (MCFA y ácidos grasos poliinsaturados (PUFA en la misma molécula de glicerol tienen ventajas nutricionales y terapéuticas. Se establece la incorporación de MCFA a los triglicéridos (TAGs de aceite de pescado, conservando un contenido considerable de ácidos docosahexaenóico (DHA y eicosapentaenóico (EPA. El efecto de diferentes acil donadores (éster metílico de ácido cáprico/MeC10 o triglicéridos de cadena media/TCM y de catalizador (químico o enzimático sobre la composición del producto de las reacciones fue estudiado. La composición de ácidos grasos de los TAGs del aceite de pescado fue modificada después de las reacciones para contener MCFA y dependió del catalizador y de los substratos. Los termogramas obtenidos por Calorimetría Diferencial de Barrido (DSC indicaron que la interesterificación provocó alteraciones considerables de

  7. Curcumin loaded PLGA-poloxamer blend nanoparticles induce cell cycle arrest in mesothelioma cells.

    Science.gov (United States)

    Mayol, Laura; Serri, Carla; Menale, Ciro; Crispi, Stefania; Piccolo, Maria Teresa; Mita, Luigi; Giarra, Simona; Forte, Maurizio; Saija, Antonina; Biondi, Marco; Mita, Damiano Gustavo

    2015-06-01

    The pharmacological potential of curcumin (CURC) is severely restricted because of its low water solubility/absorption, short half-life and poor bioavailability. To overcome these issues, CURC-loaded nanoparticles (NPs) were produced by a double emulsion technique. In particular, NPs were made up of an amphiphilic blend of poloxamers and PLGA to confer stealth properties to the NPs to take advantage of the enhanced permeability and retention (EPR) effect. Different surface properties of NPs made up of bare PLGA and PLGA/poloxamer blend were confirmed by the different interactions of these NPs with serum proteins and also by their ability to be internalized by mesothelioma cell line. The uptake of PLGA/poloxamer NPs induces a persistent block in G0/G1 phase of the cell cycle up to 72 h, thus overcoming the drug tolerance phenomenon, normally evidenced with free CURC.

  8. Physicochemical Properties of Edible Chitosan/Hydroxypropyl Methylcellulose/Lysozyme Films Incorporated with Acidic Electrolyzed Water

    Directory of Open Access Journals (Sweden)

    Ewa Brychcy

    2015-01-01

    Full Text Available The treatment with acidic electrolyzed water (AEW is a promising disinfection method due to its effectiveness in reducing microbial population. The aim of the study was to evaluate physicochemical properties of chitosan/HPMC films incorporated with lysozyme and acidic electrolyzed water. In the composite films, decreasing film solubility and increasing concentration of sodium chloride solution and prolongation of electrolysis time were observed. Electrolysis process with sodium chloride induces spongy network of film structure. The use of AEW has not changed chemical composition of films which was proved by 1H NMR, MALDI-TOF, and FT-IR spectroscopy. The research confirmed that electrolysis significantly improved thermomechanical properties of the examined films. The contact angle values of the films were quite similar and ranged between 56° and 73°. The increase of salt concentration used in the electrolysis process had an impact on increasing flexibility of samples. Application of electrolyzed water in commonly used food processing systems is possible. Fusion of AEW and biopolymers may provide better integration with coated food product and multidirectional protecting effect.

  9. Inclusion complex effect on the bioavailability of clotrimazole from poloxamer-based solid suppository.

    Science.gov (United States)

    Balakrishnan, Prabagar; Song, Chung Kil; Cho, Hyun-Jong; Yang, Su-Geun; Kim, Dae Duk; Yong, Chul Soon; Choi, Han-Gon

    2012-07-01

    To study the effect of β-cyclodextrin (βCD) inclusion complex on the bioavailability of clotrimazole from poloxamer-based suppository, formulations composed of P 188, propylene glycol and different molar ratio of clotrimazole-βCD inclusion complex were prepared. Clotrimazole (1%) has been formulated in a suppository using the thermo sensitive polymer P188 (70%) together with propylene glycol (30%). To increase its aqueous solubility, clotrimazole was incorporated as its inclusion complex at various molar ratios with βCD (1:0.25, 1:0.5, 1:1, and 1:2). The inclusion complex was characterized by differential scanning calorimetry (DSC), XRD and phase solubility studies. It was observed that the complexation with βCD, particularly at high molar ratio (F3 (1:1) and F4 (1:2)) decreased the release profile of clotrimazole considerably. However, suppositories containing inclusion complex at low molar ratio (F1 (1:0.25) and F2 (1:0.5)) showed excellent release profile compared to control formulation. In vivo study in rats at 15 mg/Kg dose showed that the F1 and F2 (82.39 ± 15.40 and 67.05 ± 8.79, respectively) significantly increased the AUC compared to that of F3 (41.48 ± 11.51), F4 (23.34 ± 8.37) and control (46.7 ± 7.87) suppositories. Thus, the suppositories containing inclusion complexes prepared at low drug to βCD molar ratio (F1) could be a potential suppository formulation to increase the bioavailability of hydrophobic drugs such as clotrimazole.

  10. A FACTORIAL STUDY ON THE EFFECTS OF HYDROXYPROPYL β CYCLODEXTRIN AND POLOXAMER ON THE SOLUBILITY AND DISSOLUTION RATE OF NIMESULIDE

    Directory of Open Access Journals (Sweden)

    K.P.R. Chowdary et al.

    2012-01-01

    Full Text Available The objective of the study is to evaluate the individual and combined effects of hydroxy propyl β cyclodextrin (HPβCD, surfactant (Poloxamer 407 on the solubility and dissolution rate of nimesulide, a BCS class II drug in a series of 22 factorial experiments. The solubility of nimesulide in four selected fluids containing HPβCD and Poloxamer 407 as per a 22 factorial study was determined. HPβCD alone gave a marginal increase (1.47 fold in the solubility of nimesulide. Whereas Poloxamer 407 alone and combination of HPβCD and Poloxamer 407 gave a significantly higher enhancement in the solubility of nimesulide, 2.5 and 6.52 fold respectively. Solid inclusion complexes of nimesulide- HPβCD were prepared with and without Poloxamer 407 by kneading method as per a 22-factorial design. Both the individual and combined effects of HPβCD and Poloxamer 407 on the solubility, dissolution rate and dissolution efficiency (DE30 of nimesulide were highly significant (P < 0.01. HPβCD and Poloxamer 407 alone gave 13.17 and 5.20 fold increase in the dissolution rate of nimesulide. Combination of HPβCD and Poloxamer 407 gave a markedly higher enhancement (21.79 fold in the dissolution rate of nimesulide. HPβCD in combination with Poloxamer 407 gave much higher enhancement in the solubility and dissolution rate of nimesulide than is possible with them individually. Hence a combination of HPβCD and Poloxamer 407 is recommended to enhance the solubility and dissolution rate of nimesulide.

  11. An amino acid depleted cell-free protein synthesis system for the incorporation of non-canonical amino acid analogs into proteins.

    Science.gov (United States)

    Singh-Blom, Amrita; Hughes, Randall A; Ellington, Andrew D

    2014-05-20

    Residue-specific incorporation of non-canonical amino acids into proteins is usually performed in vivo using amino acid auxotrophic strains and replacing the natural amino acid with an unnatural amino acid analog. Herein, we present an efficient amino acid depleted cell-free protein synthesis system that can be used to study residue-specific replacement of a natural amino acid by an unnatural amino acid analog. This system combines a simple methodology and high protein expression titers with a high-efficiency analog substitution into a target protein. To demonstrate the productivity and efficacy of a cell-free synthesis system for residue-specific incorporation of unnatural amino acids in vitro, we use this system to show that 5-fluorotryptophan and 6-fluorotryptophan substituted streptavidin retain the ability to bind biotin despite protein-wide replacement of a natural amino acid for the amino acid analog. We envisage this amino acid depleted cell-free synthesis system being an economical and convenient format for the high-throughput screening of a myriad of amino acid analogs with a variety of protein targets for the study and functional characterization of proteins substituted with unnatural amino acids when compared to the currently employed in vivo methodologies.

  12. Incorporating Geochemical And Microbial Kinetics In Reactive Transport Models For Generation Of Acid Rock Drainage

    Science.gov (United States)

    Andre, B. J.; Rajaram, H.; Silverstein, J.

    2010-12-01

    diffusion model at the scale of a single rock is developed incorporating the proposed kinetic rate expressions. Simulations of initiation, washout and AMD flows are discussed to gain a better understanding of the role of porosity, effective diffusivity and reactive surface area in generating AMD. Simulations indicate that flow boundary conditions control generation of acid rock drainage as porosity increases.

  13. THERMOPLASTIC STARCH FILMS. INFLUENCE OF INCORPORATION OF HYDROXYPROPYL-METHYL-CELLULOSE AND CITRIC ACID

    Directory of Open Access Journals (Sweden)

    Rodrigo Ortega Toro

    2014-12-01

    Full Text Available The aim of this work was to analyze the influence of citric acid (CA and hydroxypropyl-methyl-cellulose (HPMC addition in thermoplastic starch films obtained by compression-molding. Two ratios of HPMC- starch (10% and 20% were considered while starch: CA ratio was of 1: 0,01. The films were characterized as to micro- and nano-structure using Scanning Electron Microscopy (SEM and X-ray diffraction. Further, the water solubility, CA linked, mechanical and thermal properties were characterized. The starch-HPMC films showed phase separation although the glass transition analysis showed partial miscibility of the starch and HPMC which is accentuated with the addition of CA. The incorporation of HPMC and CA promoted the decrease of water vapor permeability and a slight increase in the oxygen permeability. The CA addition resulted in an increase of the elasticity modulus and decrease in the extensibility of films, which agrees with the cross-linking effect. The optical properties show a decrease in the material compactness with the CA presence causing higher film transparency

  14. Controlled release ibuprofen-poloxamer gel for epidural use - A pharmacokinetic study using microdialysis in pigs.

    Science.gov (United States)

    Paavola, Anne; Bernards, Christopher M; Rosenberg, Per H

    2016-11-01

    In order to avoid the risks of sideeffects of epidural local anesthetics and opioids, the use of nonsteroidal anti-inflammatory drugs (NSAIDs) epidurally would be an interesting option of analgesic therapy. The fairly short duration of action of spinally administered NSAIDs, e.g., ibuprofen, may be prolonged by using controlled release poloxamer gel formulation. Using a microdialysis technique we studied the epidural and intrathecal pharmacokinetics of ibuprofen after its epidural administration as a poloxamer 407 formulation or a solution formulation. In addition, plasma ibuprofen concentrations were analyzed from central venous blood samples. Ibuprofen concentrations in the epidural space were significantly higher and longer lasting after the epidural gel injection compared with the epidural solution injection. The epidural AUC of ibuprofen was over threefold greater after epidural ibuprofen gel injection compared with the ibuprofen solution injection (pgel was very low. The in situ forming poloxamer gel acted as a reservoir allowing targeted ibuprofen release at the epidural injection site and restricted ibuprofen molecules to a smaller spinal area. Ibuprofen diffusion from the epidural space to the intrathecal space was steady and prolonged. These results demonstrate that the use of epidurally injectable poloxamer gel can increase and prolong ibuprofen delivery from epidural space to the CSF enhancing thus ibuprofen entry into the central neuroaxis for spinal analgesia. Further toxicological and dose-finding studies are justified.

  15. Antibacterial Studies and Effect of Poloxamer on Gold Nanoparticles by Zingiber Officinale Extracted Green Synthesis.

    Science.gov (United States)

    Chitra, K; Reena, K; Manikandan, A; Antony, S Arul

    2015-07-01

    Poloxamer finds excellent clinical and therapeutic uses for curing of various ailments. The Zin- giber officinale (Z. officinale) is one of the well-known medicinal plants. The poloxamer188 and the rhizome extract of Z. officinale have been used to synthesize the gold nanoparticles (AuNPs) by a green approach. The Z. officinale extract has been used as a reducing agent while the polox- amerl88 has been used as a stabilizing agent. The effect of addition of poloxamer on the controlling the shape and size of the AuNPs has been investigated by transmission electron microscopy (TEM) and dynamic light scattering techniques. The formation of AuNPs has also been confirmed by UV-Visible spectral, energy dispersive X-ray (EDX) and powder X-ray diffraction (XRD) analyses. The anti-bacterial activity of the green synthesized AuNPs has been investigated on the three human pathogens Staphylococcus aureus, Escherichia coli, and Klebsiella pneumonia. The poloxamer188 protected AuNPs inhibit the bacterial growth more effectively than the pure Z. officinale extract and the standard tetracycline (TA).

  16. Thioacidolysis Marker Compound for Ferulic Acid Incorporation into Angiosperm Lignins (and an Indicator for Cinnamoyl-coenzyme-A Reductase Deficiency

    Science.gov (United States)

    A molecular marker compound, derived from lignin by the thioacidolysis degradative method, for structures produced when ferulic acid is incorporated into lignification in angiosperms (poplar, Arabidopsis, tobacco) has been structurally identified as 1,2,2-trithioethyl ethylguaiacol [1-(4-hydroxy-3-m...

  17. Prospects of In vivo Incorporation of non-canonical amino acids for the chemical diversification of antimicrobial peptides

    NARCIS (Netherlands)

    Baumann, Tobias; Nickling, Jessica H; Bartholomae, Maike; Buivydas, Andrius; Kuipers, Oscar P; Budisa, Nediljko

    2017-01-01

    The incorporation of non-canonical amino acids (ncAA) is an elegant way for the chemical diversification of recombinantly produced antimicrobial peptides (AMPs). Residue- and site-specific installation methods in several bacterial production hosts hold great promise for the generation of new-to-natu

  18. An efficient protocol for incorporation of an unnatural amino acid in perdeuterated recombinant proteins using glucose-based media

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, Vincenzo; Fawzi, Nicolas L.; Clore, G. Marius, E-mail: mariusc@mail.nih.gov [National Institutes of Health, Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases (United States)

    2012-03-15

    The in vivo incorporation of unnatural amino acids into proteins is a well-established technique requiring an orthogonal tRNA/aminoacyl-tRNA synthetase pair specific for the unnatural amino acid that is incorporated at a position encoded by a TAG amber codon. Although this technology provides unique opportunities to engineer protein structures, poor protein yields are usually obtained in deuterated media, hampering its application in the protein NMR field. Here, we describe a novel protocol for incorporating unnatural amino acids into fully deuterated proteins using glucose-based media (which are relevant to the production, for example, of amino acid-specific methyl-labeled proteins used in the study of large molecular weight systems). The method consists of pre-induction of the pEVOL plasmid encoding the tRNA/aminoacyl-tRNA synthetase pair in a rich, H{sub 2}O-based medium prior to exchanging the culture into a D{sub 2}O-based medium. Our protocol results in high level of isotopic incorporation ({approx}95%) and retains the high expression level of the target protein observed in Luria-Bertani medium.

  19. Evaluating antibiotics for use in medicine using a poloxamer biofilm model

    Directory of Open Access Journals (Sweden)

    Cochrane Christine A

    2007-02-01

    Full Text Available Abstract Background Wound infections, due to biofilms, are a constant problem because of their recalcitrant nature towards antibiotics. Appropriate antibiotic selection for the treatment of these biofilm infections is important. The traditional in vitro disc diffusion method for antibiotic selection uses bacterial cultures grown on agar plates. However, the form of bacterial growth on agar is not representative of how bacteria grow in wounds and other tissue sites as here bacteria grow naturally in a biofilm. The aim of this research was to test a more appropriate method for testing antimicrobial efficacy on biofilms and compare with the standard methods used for antibiotic sensitivity testing. Methods Outer Membrane Protein analysis was performed on E.coli, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis and Acinetobacter juni when grown on Mueller Hinton agar ('quasi-biofilm state' and 30% Poloxamer hydrogel ('true- biofilm state. Susceptibility to antibiotics on 28 clinical isolates was determined using the modified Kirby Bauer disc diffusion method, on agar and 30% Poloxamer. Results Similar outer membrane proteins [OMPs] were identified in bacteria grown in a biofilm state and on a 30% poloxamer hydrogel, which were very different to the OMPs identified in bacteria grown on Mueller-Hinton agar and broth. There was a significant difference between the means of the clearance zones around the antibiotic discs on standard agar and poloxamer gels [P 0.05]. Conclusion The findings of this experiment suggest that poloxamer gel could be used as an appropriate medium on which to conduct biofilm antibiotic susceptibility tests as it enables bacteria to be grown in a state representative of the infected surface from which the culture was taken.

  20. Formulation and characterization of novel composite semi-refined iota carrageenan-based edible film incorporating palmitic acid

    Science.gov (United States)

    Praseptiangga, Danar; Giovani, Sarah; Manuhara, Godras Jati; Muhammad, Dimas Rahadian Aji

    2017-09-01

    Novel composite films based on semi-refined iota-carrageenan (SRIC) incorporating palmitic acid (PA) were prepared by an emulsification method. Palmitic acid (PA) as hydrophobic material was incorporated into semi-refined iota-carrageenan edible films in order to improve water vapor barrier properties. Composite SRIC-based films with varying concentrations of PA (10%, 20%, and 30% w/w) were obtained by a solvent casting method. Their mechanical and barrier properties were investigated. Results showed that the incorporation of PA in films caused a significant increase (p water vapor barrier properties of the films. Water vapor transmission rate (WVTR) of the composite semi-refined iota-carrageenan-based edible film decreased significantly (p water vapor barrier properties as compared to other films with 10% and 20% w/w PA incorporation. Thus, formulation containing 30% w/w palmitic acid promoted films with a highly beneficial to improve water vapor barrier properties and it has the potential for food packaging applications.

  1. Paramagnetic relaxation enhancement of membrane proteins by incorporation of the metal-chelating unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA)

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Ho; Wang, Vivian S.; Radoicic, Jasmina; Angelis, Anna A. De; Berkamp, Sabrina; Opella, Stanley J., E-mail: sopella@ucsd.edu [University of California, San Diego, Department of Chemistry and Biochemistry (United States)

    2015-04-15

    The use of paramagnetic constraints in protein NMR is an active area of research because of the benefits of long-range distance measurements (>10 Å). One of the main issues in successful execution is the incorporation of a paramagnetic metal ion into diamagnetic proteins. The most common metal ion tags are relatively long aliphatic chains attached to the side chain of a selected cysteine residue with a chelating group at the end where it can undergo substantial internal motions, decreasing the accuracy of the method. An attractive alternative approach is to incorporate an unnatural amino acid that binds metal ions at a specific site on the protein using the methods of molecular biology. Here we describe the successful incorporation of the unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA) into two different membrane proteins by heterologous expression in E. coli. Fluorescence and NMR experiments demonstrate complete replacement of the natural amino acid with HQA and stable metal chelation by the mutated proteins. Evidence of site-specific intra- and inter-molecular PREs by NMR in micelle solutions sets the stage for the use of HQA incorporation in solid-state NMR structure determinations of membrane proteins in phospholipid bilayers.

  2. Paramagnetic relaxation enhancement of membrane proteins by incorporation of the metal-chelating unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA).

    Science.gov (United States)

    Park, Sang Ho; Wang, Vivian S; Radoicic, Jasmina; De Angelis, Anna A; Berkamp, Sabrina; Opella, Stanley J

    2015-04-01

    The use of paramagnetic constraints in protein NMR is an active area of research because of the benefits of long-range distance measurements (>10 Å). One of the main issues in successful execution is the incorporation of a paramagnetic metal ion into diamagnetic proteins. The most common metal ion tags are relatively long aliphatic chains attached to the side chain of a selected cysteine residue with a chelating group at the end where it can undergo substantial internal motions, decreasing the accuracy of the method. An attractive alternative approach is to incorporate an unnatural amino acid that binds metal ions at a specific site on the protein using the methods of molecular biology. Here we describe the successful incorporation of the unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA) into two different membrane proteins by heterologous expression in E. coli. Fluorescence and NMR experiments demonstrate complete replacement of the natural amino acid with HQA and stable metal chelation by the mutated proteins. Evidence of site-specific intra- and inter-molecular PREs by NMR in micelle solutions sets the stage for the use of HQA incorporation in solid-state NMR structure determinations of membrane proteins in phospholipid bilayers.

  3. Effect of the mode of incorporation on the disintegrant properties of acid modified water and white yam starches.

    Science.gov (United States)

    Odeku, Oluwatoyin A; Akinwande, Babatunde L

    2012-04-01

    Acid modified starches obtained from two species of yam tubers namely white yam - Dioscorea rotundata L. and water yam - D. alata L. DIAL2 have been investigated as intra- and extra-granular disintegrants in paracetamol tablet formulations. The native starches were modified by acid hydrolysis and employed as disintegrant at concentrations of 5 and 10% w/w and their disintegrant properties compared with those of corn starch BP. The tensile strength and drug release properties of the tablets, assessed using the disintegration and dissolution (t 50 and t 80 - time required for 50% and 80% of paracetamol to be released) times, were evaluated. The results showed that the tensile strength and the disintegration and dissolution times of the tablets decreased with increase in the concentration of the starch disintegrants. The acid modified yam starches showed better disintegrant efficiency than corn starch in the tablet formulations. Acid modification appeared to improve the disintegrant efficiency of the yam starches. Furthermore, tablets containing starches incorporated extragranularly showed faster disintegration but lower tensile strength than those containing starches incorporated intragranularly. This emphasizes the importance of the mode of incorporation of starch disintegrant.

  4. Thermal Behavior and Free-Radical-Scavenging Activity of Phytic Acid Alone and Incorporated in Cosmetic Emulsions

    Directory of Open Access Journals (Sweden)

    André Luis Máximo Daneluti

    2015-07-01

    Full Text Available Phytic acid is a natural compound widely used as depigmenting agent in cosmetic emulsions. Few studies are available in the literature covering the stability and the antioxidating property of this substance, used alone or into emulsions. Therefore, the purpose of this work was to investigate the thermal behavior and antioxidant properties of phytic acid alone and into cosmetic emulsions. The thermal behavior of this substance was evaluated by thermogravimetry (TG/derivative thermogravimetry (DTG and differential scanning calorimetry (DSC and the free-radical-scavenging activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH. TG/DTG and DSC curves allowed evaluation of the thermal behavior of phytic acid. These results showed that the substance presented four stages of mass loss. Thermal decomposition of the material initiated at 150 °C. Thermal behavior of the cosmetic emulsions detected that the addition of phytic acid decreased the thermal stability of the system. DPPH free-radical-scavenging activity showed that phytic acid incorporated into emulsion had no antioxidant capacity compared to BHT. In summary, we concluded that the thermoanalytical techniques (TG and DSC were efficient and reliable in the characterization of phytic acid alone and incorporated into cosmetic emulsions.

  5. Metabolic changes in deafferented central neurons of an insect, Acheta domesticus. I. Effects upon amino acid uptake and incorporation

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, M.R.; Edwards, J.S.

    1982-11-01

    Chronic cercal deafferentation of the terminal ganglion in developing crickets (Acheta domesticus), which is known to suppress normal development of giant interneuron dendritic arborizations is shown here to reduce (/sup 3/H)leucine uptake and incorporation into ganglion proteins. Short term deafferentation of adult crickets, in contrast, does not depress amino acid uptake and incorporation significantly. Following unilateral long term deafferentation of the terminal ganglion, a comparison was made of the (/sup 3/H)leucine incorporation into primary dendritic processes and somata of deafferented and normally innervated medial giant interneurons (MGIs) within the same ganglion by means of quantitative autoradiography. Grain densities within dendrites of deafferented MGIs were significantly lower than in paired control MGIs' grain densities within somata of deafferented MGIs also were reduced, although the effects of deafferentation were less pronounced in somata than in target dendrites. These results imply a specific influence of afferent innervation on protein metabolism during growth and development of target postsynaptic elements.

  6. Direct evaluation of molecular States of piroxicam/poloxamer nanosuspension by suspended-state NMR and Raman spectroscopies.

    Science.gov (United States)

    Hasegawa, Yuki; Higashi, Kenjirou; Yamamoto, Keiji; Moribe, Kunikazu

    2015-05-04

    A nanosuspension of piroxicam (PXC) and poloxamer 407 (poloxamer) prepared by the wet milling method was directly evaluated at the molecular level from the viewpoint of both solution and solid phases. (13)C solution-state NMR measurements revealed a reduction in the concentration of dissolved poloxamer in the nanosuspension. Furthermore, the fraction of dissolved poly(ethylene oxide) (PEO) chain, which is the hydrophilic part of poloxamer, was higher than that of dissolved poly(propylene oxide) (PPO) chain, the hydrophobic part. (13)C suspended-state NMR and Raman spectroscopies detected both solid-state PXC and poloxamer involved in the nanoparticles. Interestingly, the coexistence of crystalline and amorphous PXC in the nanoparticle was demonstrated. The yellow color of the nanosuspension strongly supported the existence of amorphous PXC. Changes in the peak intensity depending on the contact time in the suspended-state NMR spectrum revealed that the PEO chain of poloxamer in the nanoparticle had higher mobility compared with the PPO chain. The PEO chain should project into the water phase and form the outer layer of the nanoparticles, whereas the PPO chain should face the inner side of the nanoparticles. Amorphous PXC could be stabilized by intermolecular interaction with the PPO chain near the surface of the nanoparticles, whereas crystalline PXC could form the inner core.

  7. Imaging plasma docosahexaenoic acid (dha incorporation into the brain in vivo, as a biomarker of brain DHA: Metabolism and neurotransmission

    Directory of Open Access Journals (Sweden)

    Rapoport Stanley I.

    2011-09-01

    Full Text Available Docosahexaenoic acid (DHA is critical for normal brain structure and function, and its brain concentration depends on dietary DHA content and hepatic conversion from its dietary derived n-3 precursor, a-linolenic acid (α-LNA. We developed an in vivo method in rats using quantitative autoradiography to image incorporation into brain of unesterified plasma DHA, and showed that the incorporation rate equals the rate of brain metabolic DHA consumption. Thus, quantitative imaging of DHA incorporation from plasma into brain can be used as a biomarker of brain DHA metabolism and neurotransmission. The method has been extended to humans with the use of positron emission tomography (PET. Furthermore, imaging in unanesthetized rats using DHA incorporation as a biomarker in response to N-methyl-D-aspartate (NMDA administration confirms that regional DHA signaling is independent of extracellular calcium, and likely mediated by a calcium-independent phospholipase A2 (iPLA2. Studies in mice in which iPLA2-VIA (β was knocked out confirmed that this enzyme is critical for baseline and muscarinic cholinergic signaling involving DHA.

  8. Evolution of the genetic code by incorporation of amino acids that improved or changed protein function.

    Science.gov (United States)

    Francis, Brian R

    2013-10-01

    Fifty years have passed since the genetic code was deciphered, but how the genetic code came into being has not been satisfactorily addressed. It is now widely accepted that the earliest genetic code did not encode all 20 amino acids found in the universal genetic code as some amino acids have complex biosynthetic pathways and likely were not available from the environment. Therefore, the genetic code evolved as pathways for synthesis of new amino acids became available. One hypothesis proposes that early in the evolution of the genetic code four amino acids-valine, alanine, aspartic acid, and glycine-were coded by GNC codons (N = any base) with the remaining codons being nonsense codons. The other sixteen amino acids were subsequently added to the genetic code by changing nonsense codons into sense codons for these amino acids. Improvement in protein function is presumed to be the driving force behind the evolution of the code, but how improved function was achieved by adding amino acids has not been examined. Based on an analysis of amino acid function in proteins, an evolutionary mechanism for expansion of the genetic code is described in which individual coded amino acids were replaced by new amino acids that used nonsense codons differing by one base change from the sense codons previously used. The improved or altered protein function afforded by the changes in amino acid function provided the selective advantage underlying the expansion of the genetic code. Analysis of amino acid properties and functions explains why amino acids are found in their respective positions in the genetic code.

  9. Effects of temporary vascular occluder poloxamer 407 Gel on the endothelium

    Directory of Open Access Journals (Sweden)

    Gucu Arif

    2013-01-01

    Full Text Available Abstract Background Coronary occlusion techniques during OPCAB may lead to an endothelial damage to the target vessel. The adverse effects of these techniques are well-known, and researches have been trying to find out new materials to occlude the coronary artery without an endothelial damage. In the present study, we investigate to the endothelial damage in the rat aorta which is occluded by Poloxamer 407 gel. Methods Forty-five rats were randomized in three groups: (1 segment of the aorta was occluded with Poloxamer 407 gel in P 407 group; (2 segment of the aorta was occluded with microvascular clamp in MV clamp group; and (3 no onclusion was available in the Control group. The rats were sacrificed of observation, and a 15mm segment of the aorta was obtained as a specimen. Integrity of the endothelial lining was observed with a scanning electron microscopy. Results Scanning electron microscopy revealed a statistically significant difference among the 3 groups (p Conclusions We suggest that Poloxamer 407 gel occlusion may be a safer and more effective method compared to the microvascular clamp occlusion.

  10. Glycol chitosan incorporated retinoic acid chlorochalcone (RACC) nanoparticles in the treatment of Osteosarcoma.

    Science.gov (United States)

    Qin, Yan-Guo; Zhu, Lan-Yu; Wang, Chen-Yu; Zhang, Bo-Yan; Wang, Qing-Yu; Li, Rui-Yan; Liu, Zhen

    2015-07-14

    Osteosarcoma is the most common of all the bone malignancies and accounts for 30-80% of the primary skeletal sarcomas. The overall survival rate of patients with osteosarcoma is osteosarcoma cells. MG-63 and Saos-2 osteosarcoma cells were transfected with various concentrations of RACC-incorporated GC nanoparticle for 24 h. The effect on cell proliferation, Ezh2 expression, apoptosis, cell cycle arrest, cell migration and invasiveness, Akt phosphorylation and local tumour growth and metastases were studied. MG-63 and Saos-2 osteosarcoma cells on RACC-incorporated GC nanoparticle transfection for 24 h showed a concentration-dependent inhibition of cell proliferation. Of the various concentrations of RACC tested, the effective concentration started from 5 μM with an IC50 of 20 μM. Wound healing assay also showed that RACC-incorporated GC nanoparticles inhibited migration of tumor cells more effectively compared to the parent RA. RACC transfection resulted in inhibition of cell proliferation, Ezh2 expression inhibition, apoptosis through mitochondrial pathway by decrease in membrane potential and release of cytochrome c and cell cycle arrest in the G0/G1 phase. The invasiveness of cells treated with 5 and 20 μM RACC was decreased by 49 and 76% respectively, compared to the control. RACC-treated mice showed significantly lower number of metastases compared to that in the control mice. Thus, RACC-incorporated glycol chitosan nanoparticle strategy can be promising for the treatment of osteosarcoma.

  11. Novel artificial metalloenzymes by in vivo incorporation of metal-binding unnatural amino acids

    NARCIS (Netherlands)

    Drienovska, Ivana; Rioz-Martinez, Ana; Draksharapu, Apparao; Roelfes, Gerard

    2015-01-01

    Artificial metalloenzymes have emerged as an attractive new approach to enantioselective catalysis. Herein, we introduce a novel strategy for preparation of artificial metalloenzymes utilizing amber stop codon suppression methodology for the in vivo incorporation of metal-binding unnatural amino aci

  12. Glycerol-3-phosphate acyltransferase-2 is expressed in spermatic germ cells and incorporates arachidonic acid into triacylglycerols.

    Directory of Open Access Journals (Sweden)

    Elizabeth R Cattaneo

    Full Text Available BACKGROUND: De novo glycerolipid synthesis begins with the acylation of glycerol-3 phosphate catalyzed by glycerol-3-phosphate acyltransferase (GPAT. In mammals, at least four GPAT isoforms have been described, differing in their cell and tissue locations and sensitivity to sulfhydryl reagents. In this work we show that mitochondrial GPAT2 overexpression in CHO-K1 cells increased TAG content and both GPAT and AGPAT activities 2-fold with arachidonoyl-CoA as a substrate, indicating specificity for this fatty acid. METHODS AND RESULTS: Incubation of GPAT2-transfected CHO-K1 cells with [1-(14C]arachidonate for 3 h increased incorporation of [(14C]arachidonate into TAG by 40%. Consistently, arachidonic acid was present in the TAG fraction of cells that overexpressed GPAT2, but not in control cells, corroborating GPAT2's role in synthesizing TAG that is rich in arachidonic acid. In rat and mouse testis, Gpat2 mRNA was expressed only in primary spermatocytes; the protein was also detected in late stages of spermatogenesis. During rat sexual maturation, both the testicular TAG content and the arachidonic acid content in the TAG fraction peaked at 30 d, matching the highest expression of Gpat2 mRNA and protein. CONCLUSIONS: These results strongly suggest that GPAT2 expression is linked to arachidonoyl-CoA incorporation into TAG in spermatogenic germ cells.

  13. Genetic Incorporation of the Unnatural Amino Acid p-Acetyl Phenylalanine into Proteins for Site-Directed Spin Labeling

    Science.gov (United States)

    Evans, Eric G.B.; Millhauser, Glenn L.

    2016-01-01

    Site-directed spin labeling (SDSL) is a powerful tool for the characterization of protein structure and dynamics; however, its application in many systems is hampered by the reliance on unique and benign cysteine substitutions for the site-specific attachment of the spin label. An elegant solution to this problem involves the use of genetically encoded unnatural amino acids (UAAs) containing reactive functional groups that are chemically orthogonal to those of the 20 amino acids found naturally in proteins. These unique functional groups can then be selectively reacted with an appropriately functionalized spin probe. In this chapter, we detail the genetic incorporation of the ketone-bearing amino acid p-acetyl phenylalanine (pAcPhe) into recombinant proteins expressed in E. coli. Incorporation of pAcPhe is followed by chemoselective reaction of the ketone side chain with a hydroxylamine-functionalized nitroxide to afford the spin-labeled side chain “K1,” and we present two protocols for successful K1 labeling of proteins bearing site-specific pAcPhe. We outline the basic requirements for pAcPhe incorporation and labeling, with an emphasis on practical aspects that must be considered by the researcher if high yields of UAA incorporation and efficient labeling reactions are to be achieved. To this end, we highlight recent advances that have led to increased yields of pAcPhe incorporation, and discuss the use of aniline-based catalysts allowing for facile conjugation of the hydroxylamine spin label under mild reaction conditions. To illustrate the utility of K1 labeling in proteins where traditional cysteine-based SDSL methods are problematic, we site-specifically K1 label the cellular prion protein at two positions in the C-terminal domain and determine the interspin distance using double electron–electron resonance EPR. Recent advances in UAA incorporation and ketone-based bioconjugation, in combination with the commercial availability of all requisite

  14. Genetic Incorporation of the Unnatural Amino Acid p-Acetyl Phenylalanine into Proteins for Site-Directed Spin Labeling.

    Science.gov (United States)

    Evans, Eric G B; Millhauser, Glenn L

    2015-01-01

    Site-directed spin labeling (SDSL) is a powerful tool for the characterization of protein structure and dynamics; however, its application in many systems is hampered by the reliance on unique and benign cysteine substitutions for the site-specific attachment of the spin label. An elegant solution to this problem involves the use of genetically encoded unnatural amino acids (UAAs) containing reactive functional groups that are chemically orthogonal to those of the 20 amino acids found naturally in proteins. These unique functional groups can then be selectively reacted with an appropriately functionalized spin probe. In this chapter, we detail the genetic incorporation of the ketone-bearing amino acid p-acetyl phenylalanine (pAcPhe) into recombinant proteins expressed in E. coli. Incorporation of pAcPhe is followed by chemoselective reaction of the ketone side chain with a hydroxylamine-functionalized nitroxide to afford the spin-labeled side chain "K1," and we present two protocols for successful K1 labeling of proteins bearing site-specific pAcPhe. We outline the basic requirements for pAcPhe incorporation and labeling, with an emphasis on practical aspects that must be considered by the researcher if high yields of UAA incorporation and efficient labeling reactions are to be achieved. To this end, we highlight recent advances that have led to increased yields of pAcPhe incorporation, and discuss the use of aniline-based catalysts allowing for facile conjugation of the hydroxylamine spin label under mild reaction conditions. To illustrate the utility of K1 labeling in proteins where traditional cysteine-based SDSL methods are problematic, we site-specifically K1 label the cellular prion protein at two positions in the C-terminal domain and determine the interspin distance using double electron-electron resonance EPR. Recent advances in UAA incorporation and ketone-based bioconjugation, in combination with the commercial availability of all requisite reagents

  15. Fasting increases palmitic acid incorporation into rat hind-limb intramuscular acylglycerols while short-term cold exposure has no effect.

    Science.gov (United States)

    Synak, M; Zarzeczny, R; Górecka, M; Langfort, J; Kaciuba-Uściłko, H; Zernicka, Ewa

    2011-09-01

    The aim of the study was to investigate the palmitic acid incorporation into intramuscular acylglycerols in perfused hind-limb skeletal muscles of different fibre types in rats either fasted for 48 h or exposed to cold (6 °C) for 12 h. Hind-limb preparations of fasted and cold exposed rats were perfused with buffers containing tritium labelled and cold palmitic acid. Palmitic acid incorporation into intracellular lipid pools in the soleus, plantaris, red and white gastrocnemius and red and white quadriceps was measured. It was found that fasting increased approximately 2-fold palmitic acid incorporation in all muscles examined regardless of the fibre type composition of the muscle. On the other hand, exposure to cold had no effect on the palmitic acid incorporation into intramuscular acylglycerols regardless the muscle fibre type. The increased incorporation of palmitic acid into acylglycerols in fasted animals is in line with data showing that 48 h fasting stimulates the expression of plasma membrane proteins putatively facilitating fatty acid uptake. It appears that although 12 h cold exposure increases the use of fatty acids as energy substrates it does not alter the incorporation of palmitic acid into intramuscular acylglycerols in the perfused rat hind-limb.

  16. Oxidation and sensing of ascorbic acid and dopamine on self-assembled gold nanoparticles incorporated within polyaniline film

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Wenya [College of Chemistry, Chemical Engineering and Materials Science, and Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, Soochow University, Suzhou 215123 (China); Zhou, Qun, E-mail: zhq@suda.edu.cn [College of Chemistry, Chemical Engineering and Materials Science, and Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, Soochow University, Suzhou 215123 (China); Li, Shuangshuang [College of Chemistry, Chemical Engineering and Materials Science, and Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, Soochow University, Suzhou 215123 (China); College of Physics, Optoelectronics and Energy, Soochow University, Suzhou 215006 (China); Zhao, Wei; Li, Na [College of Chemistry, Chemical Engineering and Materials Science, and Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, Soochow University, Suzhou 215123 (China); Zheng, Junwei, E-mail: jwzheng@suda.edu.cn [College of Chemistry, Chemical Engineering and Materials Science, and Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, Soochow University, Suzhou 215123 (China); College of Physics, Optoelectronics and Energy, Soochow University, Suzhou 215006 (China)

    2015-10-30

    Highlights: • Gold nanoparticles assembled on electrodes are incorporated into polyaniline film. • Composite film electrodes exhibit synergistic effect on electrocatalytic oxidation. • Ascorbic acid and dopamine can be detected simultaneously on composite electrodes. - Abstract: Electrochemical biosensors based on conducting polymers incorporated with metallic nanoparticles can greatly enhance sensitivity and selectivity. Herein, we report a facile fabrication approach for polyaniline (PAN) incorporated with a gold nanoparticle (AuNP) composite electrode by electrodeposition of PAN on a self-assembled AuNP layer on the surface of an indium tin oxide electrode. The resulting AuNP/PAN composite electrode exhibits a remarkable synergistic effect on the electrocatalytic oxidation of ascorbic acid (AA) and dopamine (DA). It is demonstrated that the oxidation reaction of AA mainly occurs at AuNPs inside the PAN film as the ascorbate anions are doped into the polymer during the oxidation of the PAN film. Conversely, the oxidation of positively charged DA may only take place at the PAN/solution interface. The different mechanisms of the electrode reactions result in the oxidation of AA and DA occurring at different potentials. As a result, the AuNP/PAN composite electrode can be employed to simultaneously detect AA and DA with a good linear range, high sensitivity, and low detection limit.

  17. Characterization of Active Packaging Films Made from Poly(Lactic Acid/Poly(Trimethylene Carbonate Incorporated with Oregano Essential Oil

    Directory of Open Access Journals (Sweden)

    Dong Liu

    2016-05-01

    Full Text Available Antimicromial and antioxidant bioactive films based on poly(lactic acid/poly(trimenthylene carbonate films incorporated with different concentrations of oregano essential oil (OEO were prepared by solvent casting. The antimicrobial, antioxidant, physical, thermal, microstructural, and mechanical properties of the resulting films were examined. Scanning electron microscopy analysis revealed that the cross-section of films became rougher when OEO was incorporated into PLA/PTMC blends. Differential scanning calorimetry analysis indicated that crystallinity of PLA phase decreased by the addition of OEO, but this did not affect the thermal stability of the films. Water vapor permeability of films slightly increased with increasing concentration of OEO. However, active PLA/PTMC/OEO composite films showed adequate barrier properties for food packaging application. The antimicrobial and antioxidant capacities were significantly improved with the incorporation of OEO (p < 0.05. The results demonstrated that an optimal balance between the mechanical, barrier, thermal, antioxidant, and antimicrobial properties of the films was achieved by the incorporation of 9 wt % OEO into PLA/PTMC blends.

  18. Emulsion polymerization of polystyrene-co-acrylic acid with Cu2O incorporation

    Science.gov (United States)

    Fahmiati, Sri; Harmami, Sri Budi; Meliana, Yenny; Haryono, Agus

    2017-01-01

    In this research, poly(styrene-co-acrylic acid-Cu) was prepared via emulsion polymerization.Cu contents were varied as 10%, 15% and 20% and mol ratio of styrene to acrylic acid as 1:1 and 2:1. Structure and surface of poly(styrene-co-acrylic acid-Cu) were characterized by FTIR (Fourier Transformed Infra Red), NMR (Nuclear Magnetic Resonance), and SEM/EDX (Scanning Electron Microcope/ Energy Dispersive X-Ray) spectroscopy. The NMR spectra showed that the polymer was formed, however FTIR spectra showed that there were still unreacted monomers. SEM-EDX confirmed that copper (Cu) was dispersed uniformly on poly(styrene-co-acrylic acid-Cu) matrix.

  19. Incorporation of N-amidino-pyroglutamic acid into peptides using intramolecular cyclization of alpha-guanidinoglutaric acid.

    Science.gov (United States)

    Burov, Sergey; Moskalenko, Yulia; Dorosh, Marina; Shkarubskaya, Zoya; Panarin, Evgeny

    2009-11-01

    N-terminal modification of peptides by unnatural amino acids significantly affects their enzymatic stability, conformational properties and biological activity. Application of N-amidino-amino acids, positively charged under physiological conditions, can change peptide conformation and its affinity to the corresponding receptor. In this article, we describe synthesis of short peptides, containing a new building block-N-amidino-pyroglutamic acid. Although direct guanidinylation of pyroglutamic acid and oxidation of N-amidino-proline using RuO(4) did not produce positive results, N-amidino-Glp-Phe-OH was synthesized on Wang polymer by cyclization of alpha-guanidinoglutaric acid residue. In the course of synthesis, it was found that literature procedure of selective Boc deprotection using TMSOTf/TEA reagent is accompanied by concomitant side reaction of triethylamine alkylation by polymer linker fragment. It should be mentioned that independently from cyclization time and coupling agent (DIC or HCTU), the lactam formation was incomplete. Separation of the cyclic product from the linear precursor was achieved by HPLC in ammonium formate buffer at pH 6. HPLC analysis showed N-amidino-Glp-Phe-OH stability at acidic and physiological pH and fast ring opening in water solution at pH 9. The suggested method of N-amidino-Glp residue formation can be applied in the case of short peptide chains, whereas synthesis of longer ones will require fragment condensation approach.

  20. A tRNA body with high affinity for EF-Tu hastens ribosomal incorporation of unnatural amino acids.

    Science.gov (United States)

    Ieong, Ka-Weng; Pavlov, Michael Y; Kwiatkowski, Marek; Ehrenberg, Måns; Forster, Anthony C

    2014-05-01

    There is evidence that tRNA bodies have evolved to reduce differences between aminoacyl-tRNAs in their affinity to EF-Tu. Here, we study the kinetics of incorporation of L-amino acids (AAs) Phe, Ala allyl-glycine (aG), methyl-serine (mS), and biotinyl-lysine (bK) using a tRNA(Ala)-based body (tRNA(AlaB)) with a high affinity for EF-Tu. Results are compared with previous data on the kinetics of incorporation of the same AAs using a tRNA(PheB) body with a comparatively low affinity for EF-Tu. All incorporations exhibited fast and slow phases, reflecting the equilibrium fraction of AA-tRNA in active ternary complex with EF-Tu:GTP before the incorporation reaction. Increasing the concentration of EF-Tu increased the amplitude of the fast phase and left its rate unaltered. This allowed estimation of the affinity of each AA-tRNA to EF-Tu:GTP during translation, showing about a 10-fold higher EF-Tu affinity for AA-tRNAs formed from the tRNA(AlaB) body than from the tRNA(PheB) body. At ∼1 µM EF-Tu, tRNA(AlaB) conferred considerably faster incorporation kinetics than tRNA(PheB), especially in the case of the bulky bK. In contrast, the swap to the tRNA(AlaB) body did not increase the fast phase fraction of N-methyl-Phe incorporation, suggesting that the slow incorporation of N-methyl-Phe had a different cause than low EF-Tu:GTP affinity. The total time for AA-tRNA release from EF-Tu:GDP, accommodation, and peptidyl transfer on the ribosome was similar for the tRNA(AlaB) and tRNA(PheB) bodies. We conclude that a tRNA body with high EF-Tu affinity can greatly improve incorporation of unnatural AAs in a potentially generalizable manner.

  1. Recent Developments of Engineered Translational Machineries for the Incorporation of Non-Canonical Amino Acids into Polypeptides

    Directory of Open Access Journals (Sweden)

    Naohiro Terasaka

    2015-03-01

    Full Text Available Genetic code expansion and reprogramming methodologies allow us to incorporate non-canonical amino acids (ncAAs bearing various functional groups, such as fluorescent groups, bioorthogonal functional groups, and post-translational modifications, into a desired position or multiple positions in polypeptides both in vitro and in vivo. In order to efficiently incorporate a wide range of ncAAs, several methodologies have been developed, such as orthogonal aminoacyl-tRNA-synthetase (AARS–tRNA pairs, aminoacylation ribozymes, frame-shift suppression of quadruplet codons, and engineered ribosomes. More recently, it has been reported that an engineered translation system specifically utilizes an artificially built genetic code and functions orthogonally to naturally occurring counterpart. In this review we summarize recent advances in the field of ribosomal polypeptide synthesis containing ncAAs.

  2. Incorporation of titanate nanosheets to enhance mechanical properties of water-soluble polyamic acid

    Science.gov (United States)

    Harito, C.; Bavykin, Dmitry V.; Walsh, Frank C.

    2017-07-01

    Pyromeliticdianhydride (PMDA) and 4’,4’-oxydianiline (ODA) were used as monomers of polyimide. To synthesise a water soluble polyimide precursor (polyamic acid salt), triethylamine (TEA) was added to polyamic acid with a TEA/COOH mole ratio of 1:1. Titanate nanosheets were synthesised by solid-state reaction, ion-exchanged with acid, and exfoliated by TEA. Exfoliated titanate nanosheets were mixed with water soluble polyamic acid salt as reinforcing filler. Drop casting was deployed to synthesise polyamic acid/titanate nanosheet nanocomposite films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to study the morphology and dispersion of nanosheets in the colloidal dispersion and the solid film composite. Modulus and hardness of nanocomposites was provided by nanoindentation. Hardness increased by 90% with addition of 2% TiNS while modulus increased by 103% compared to pure polymer. This behaviour agrees well with Halpin-Tsai theoretical predictions up to 2 wt% filler loading; agglomeration occurs at higher concentrations.

  3. MORTAR INCORPORATING SUPPLEMENTARY CEMENTITIOUS MATERIALS: STRENGTH, ISOTHERMAL CALORIMETRY AND ACIDS ATTACK

    Directory of Open Access Journals (Sweden)

    Y. Senhadji

    2016-05-01

    Full Text Available Supplementary cementitious materials (SCMs prove to be effective to meet most of the requirements of durable concrete and leads to a significant reduction in CO2 emissions. This research studies the effect different SCMs (natural pozzolan (PN/ limestone fine (FC at various remplacement levels on the physical and mechano-chemical resistance of blended mortar. The paper primarily deals with the characteristics of these materials, including heat of hydration, strength and effects of aggressive chemical environments (using sulphuric acid and nitric acid. Over 6 mixes were made and compared to the control mix. Tests were conducted at different ages up to 360 days. The experimental results in general showed that Algerian mineral admixtures (PN/FC were less vulnerable to nitric and sulphuric acid attack and improved the properties of mortars, but at different rates depending on the quantity of binder.

  4. Considerations for incorporating eicosapentaenoic and docosahexaenoic omega-3 fatty acids into the military food supply chain.

    Science.gov (United States)

    Ismail, Adam; Rice, Harry B

    2014-11-01

    The U.S. military may consider exploring the inclusion of the long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the diets of active duty military personnel. To be successful, certain challenges must be overcome including determining appropriate dosage, ensuring cost efficiency, and optimizing stability. To increase EPA and DHA intake, the military should consider using one of three strategies, including mandates or recommendations on omega-3 supplement usage, contracts to purchase commercially available foods for distribution in the food supply chain, or direct addition of EPA and DHA into currently consumed foods. This review presents the challenges and strategies and provides potential suggestions to the military to increase the likelihood of success.

  5. Isotopic labeling of mouse interferon by incorporation of radioactive amino acids during synthesis

    Energy Technology Data Exchange (ETDEWEB)

    DeMaeyer-Guignard, J.; Cachard, A.; DeMaeyer, E.

    1982-07-30

    Mouse interferon produced by C-243 cells induced with Newcastle disease virus was isotopically labeled by adding either (/sup 35/S)methionine or a /sup 14/C-labeled amino acid mixture to the culture medium. A method combining butyric acid and theophylline treatment and resulting in high interferon yields was used. Following purification by two-step affinity chromatography on poly(U) and antibody columns, the resulting material was analyzed on SDS-PAGE. The migration pattern of radioactivity and interferon coincided well and autoradiography revealed three major bands at migration distances corresponding, respectively, to 35, 28, and 22 K. Interferon represented 3.8% of all (/sup 35/S)methionine-labeled proteins and 2.6% of all /sup 14/C-amino acid-labeled proteins released into the medium.

  6. Electrochemical Behavior of Methanol Influenced by Polyaniline Incorporated with Ferrocenesulfonic-carboxylic Acid

    Institute of Scientific and Technical Information of China (English)

    NDAMANISHA Jean Chrysostome; WANG Hui; GUO Li-ping

    2005-01-01

    After the synthesis of polyaniline in the presence of ferrocenesulfoniccarboxylic acid, its influence on the electrochemical reaction of methanol was studied. The result indicates that the ferrocenyl in ferrocenesulfoniccarboxylic acid plays an important role in the electrocatalytic oxidation of methanol. CH3OH is adsorbed on PANI-Fc before its electrocatalytic oxidation. When the concentration of methanol is 2 mol/L, it begins to be oxidized. The effect of scan rate on the electrochemical reaction of methanol was also studied and 5 mV/s was favourable. It is another method to insert a metal catalyst in polyaniline without its electrodeposition.

  7. Antimicrobial activity of nisin incorporated in pectin and polylactic acid composite films against Listeria monocytogenes

    Science.gov (United States)

    Extruded composite films from 20% pectin and 80% polylactic acids (PLA) were developed and nisin was loaded into films by a diffusion post extrusion. Inhibitory activities of the films against Listeria monocytogenes were evaluated in brain heart infusion (BHI) broth, liquid egg white and orange juic...

  8. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with fis

  9. Amino acids-incorporated nanoflowers with an intrinsic peroxidase-like activity

    Science.gov (United States)

    Wu, Zhuo-Fu; Wang, Zhi; Zhang, Ye; Ma, Ya-Li; He, Cheng-Yan; Li, Heng; Chen, Lei; Huo, Qi-Sheng; Wang, Lei; Li, Zheng-Qiang

    2016-03-01

    Functional molecules synthesized by self-assembly between inorganic salts and amino acids have attracted much attention in recent years. A simple method is reported here for fabricating hybrid organic–inorganic nanoflowers using copper (II) ions as the inorganic component and natural amino acids as the organic component. The results indicate that the interactions between amino acid and copper ions cause the growth of the nanoflowers composed by C, N, Cu, P and O elements. The Cu ions and Cu(AA)n complexes containing Cu-O bond are present in the nanoflowers. The nanoflowers have flower-like porous structure dominated by the R groups of amino acids with high surface-to-volume ratios, which is beneficial for exerting its peroxidase-like activity depending on Fenton-like reaction mechanism with ABTS and Rhodamine B as the substrates. It is expected that the nanoflowers hold great promise as enzyme mimics for application in the field of biosensor, bioanalysis and biocatalysis.

  10. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with fis

  11. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with

  12. Alpha-synuclein gene ablation increases docosahexaenoic acid incorporation and turnover in brain phospholipids

    DEFF Research Database (Denmark)

    Golovko, Mikhail Y; Rosenberger, Thad A; Feddersen, Søren

    2007-01-01

    Previously, we demonstrated that ablation of alpha-synuclein (Snca) reduces arachidonate (20:4n-6) turnover in brain phospholipids through modulation of an endoplasmic reticulum-localized acyl-CoA synthetase (Acsl). The effect of Snca ablation on docosahexaenoic acid (22:6n-3) metabolism is unkno...

  13. 13C Incorporation into Signature Fatty Acids as an Assay for Carbon Allocation in Arbuscular Mycorrhiza

    Science.gov (United States)

    Olsson, Pål Axel; van Aarle, Ingrid M.; Gavito, Mayra E.; Bengtson, Per; Bengtsson, Göran

    2005-01-01

    The ubiquitous arbuscular mycorrhizal fungi consume significant amounts of plant assimilated C, but this C flow has been difficult to quantify. The neutral lipid fatty acid 16:1ω5 is a quantitative signature for most arbuscular mycorrhizal fungi in roots and soil. We measured carbon transfer from four plant species to the arbuscular mycorrhizal fungus Glomus intraradices by estimating 13C enrichment of 16:1ω5 and compared it with 13C enrichment of total root and mycelial C. Carbon allocation to mycelia was detected within 1 day in monoxenic arbuscular mycorrhizal root cultures labeled with [13C]glucose. The 13C enrichment of neutral lipid fatty acid 16:1ω5 extracted from roots increased from 0.14% 1 day after labeling to 2.2% 7 days after labeling. The colonized roots usually were more enriched for 13C in the arbuscular mycorrhizal fungal neutral lipid fatty acid 16:1ω5 than for the root specific neutral lipid fatty acid 18:2ω6,9. We labeled plant assimilates by using 13CO2 in whole-plant experiments. The extraradical mycelium often was more enriched for 13C than was the intraradical mycelium, suggesting rapid translocation of carbon to and more active growth by the extraradical mycelium. Since there was a good correlation between 13C enrichment in neutral lipid fatty acid 16:1ω5 and total 13C in extraradical mycelia in different systems (r2 = 0.94), we propose that the total amount of labeled C in intraradical and extraradical mycelium can be calculated from the 13C enrichment of 16:1ω5. The method described enables evaluation of C flow from plants to arbuscular mycorrhizal fungi to be made without extraction, purification and identification of fungal mycelia. PMID:15870350

  14. Lactobacillus plantarum as source of conjugated linoleic acid: Effect of pH, incubation Temperature and inulin incorporation.

    Directory of Open Access Journals (Sweden)

    Carmen Soto

    2013-07-01

    Full Text Available The effect of pH and temperature, and inulin use, on the growth andthe fatty acid profile of Lactobacillus plantarum strain wereevaluated. The best results were obtained at 6.5 pH broth, producing3.2 g/L of biomass and about 20% of conjugated linoleic acid(CLA in the cell lipids. Similar growth was observed with 37 and45ºC, but a low CLA content (10.6% was achieved at 45°C. In thecase of inulin incorporation, a low biomass concentration (1 g/Land low production of CLA (12.4% were observed. These resultssuggest a pH and temperature dependence on CLA production bythe microorganism.

  15. From amino acids to nature-inspired molecular scaffolds: incorporation of medium-sized bridged heterocycles into a peptide backbone.

    Science.gov (United States)

    La-Venia, Agustina; Ventosa-Andrés, Pilar; Hradilová, Ludmila; Krchňák, Viktor

    2014-11-07

    Novel molecular scaffolds comprising two to four bridged and fused heterocycles were synthesized from amino acids using seven-membered endocyclic N-acyliminium ions as key intermediates in acid-mediated tandem reactions with internal nucleophiles. This complexity-generating synthesis proceeds with high efficiency and with full stereocontrol of the newly generated stereogenic center. These results have extended the scope of medium-sized cyclic iminium ion chemistry, making it applicable as a regio- and stereoselective synthetic strategy for the generation of complex polycyclic structures. Furthermore, its compatibility with the traditional Merrifield synthesis of peptides on solid supports allowed the incorporation of the previously unexplored conformationally restricted cyclic systems into peptides without a need to independently synthesize the scaffold.

  16. Synthesis and biological evaluation of new salvinorin A analogues incorporating natural amino acids.

    Science.gov (United States)

    Fichna, Jakub; Lewellyn, Kevin; Yan, Feng; Roth, Bryan L; Zjawiony, Jordan K

    2011-01-01

    The synthesis and in vitro evaluation of a new series of salvinorin A analogues substituted at the C(2) position with natural amino acids is reported. Compound 12, containing Val, displayed high affinity and full agonist activity at the kappa-opioid receptor. Analogues with bulky and/or aromatic residues were inactive, showing the importance of size and electronegativity of C(2)-substituents for binding affinity of salvinorin A derivatives.

  17. Evidence for a universal pathway of abscisic acid biosynthesis in higher plants from sup 18 O incorporation patterns

    Energy Technology Data Exchange (ETDEWEB)

    Zeevaart, J.A.D.; Heath, T.G.; Gage, D.A. (Michigan State University, East Lansing (USA))

    1989-12-01

    Previous labeling studies of abscisic acid (ABA) with {sup 18}O{sub 2} have been mainly conducted with water-stressed leaves. In this study, {sup 18}O incorporation into ABA of stressed leaves of various species was compared with {sup 18}O labeling of ABA of turgid leaves and of fruit tissue in different stages of ripening. In stressed leaves of all six species investigated, avocado (Persea americana), barley (Hordeum vulgare), bean (Phaseolus vulgaris), cocklebur (Xanthium strumarium), spinach (Spinacia oleracea), and tobacco (Nicotiana tabacum), {sup 18}O was most abundant in the carboxyl group, whereas incorporation of a second and third {sup 18}O in the oxygen atoms on the ring of ABA was much less prominent after 24 h in {sup 18}O{sub 2}. ABA from turgid bean leaves showed significant {sup 18}O incorporation, again with highest {sup 18}O enrichment in the carboxyl group. On the basis of {sup 18}O-labeling patterns observed in ABA from different tissues it is concluded that, despite variations in precusor pool sizes and intermediate turnover rates, there is a universal pathway of ABA biosynthesis in higher plants which involves cleavage of a larger precursor molecule, presumably an oxygenated carotenoid.

  18. 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.

  19. Synthetic Cyclolipopeptides Selective against Microbial, Plant and Animal Cell Targets by Incorporation of D-Amino Acids or Histidine.

    Science.gov (United States)

    Vilà, Sílvia; Badosa, Esther; Montesinos, Emilio; Planas, Marta; Feliu, Lidia

    2016-01-01

    Cyclolipopeptides derived from the antimicrobial peptide c(Lys-Lys-Leu-Lys-Lys-Phe-Lys-Lys-Leu-Gln) (BPC194) were prepared on solid-phase and screened against four plant pathogens. The incorporation at Lys5 of fatty acids of 4 to 9 carbon atoms led to active cyclolipopeptides. The influence on the antimicrobial activity of the Lys residue that is derivatized was also evaluated. In general, acylation of Lys1, Lys2 or Lys5 rendered the sequences with the highest activity. Incorporation of a D-amino acid maintained the antimicrobial activity while significantly reduced the hemolysis. Replacement of Phe with a His also yielded cyclolipopeptides with low hemolytic activity. Derivatives exhibiting low phytotoxicity in tobacco leaves were also found. Interestingly, sequences with or without significant activity against phytopathogenic bacteria and fungi, but with differential hemolysis and phytotoxicity were identified. Therefore, this study represents an approach to the development of bioactive peptides with selective activity against microbial, plant and animal cell targets. These selective cyclolipopeptides are candidates useful not only to combat plant pathogens but also to be applied in other fields.

  20. Synthetic Cyclolipopeptides Selective against Microbial, Plant and Animal Cell Targets by Incorporation of D-Amino Acids or Histidine.

    Directory of Open Access Journals (Sweden)

    Sílvia Vilà

    Full Text Available Cyclolipopeptides derived from the antimicrobial peptide c(Lys-Lys-Leu-Lys-Lys-Phe-Lys-Lys-Leu-Gln (BPC194 were prepared on solid-phase and screened against four plant pathogens. The incorporation at Lys5 of fatty acids of 4 to 9 carbon atoms led to active cyclolipopeptides. The influence on the antimicrobial activity of the Lys residue that is derivatized was also evaluated. In general, acylation of Lys1, Lys2 or Lys5 rendered the sequences with the highest activity. Incorporation of a D-amino acid maintained the antimicrobial activity while significantly reduced the hemolysis. Replacement of Phe with a His also yielded cyclolipopeptides with low hemolytic activity. Derivatives exhibiting low phytotoxicity in tobacco leaves were also found. Interestingly, sequences with or without significant activity against phytopathogenic bacteria and fungi, but with differential hemolysis and phytotoxicity were identified. Therefore, this study represents an approach to the development of bioactive peptides with selective activity against microbial, plant and animal cell targets. These selective cyclolipopeptides are candidates useful not only to combat plant pathogens but also to be applied in other fields.

  1. Incorporation of n-3 fatty acids by the liver of mice fed linseed oil as a function of feeding duration

    Directory of Open Access Journals (Sweden)

    João Angelo Lima Perini

    2011-04-01

    Full Text Available The objective of this study was to evaluate the incorporation of omega-3 fatty acids (n-3 FA on male Swiss mice livers receiving diets based on linseed oil (LO for up to 56 days. The mice were sacrificed at 7, 14, 28, 42, 56 days and FA concentration was analyzed by gas chromatography. A total of 13 FA were identified on LO feeds presenting alpha-linolenic acid (LNA contents of 26.97 %. A total 22 FA were identified in the livers of the mice. Part of the LNA was converted into n-3 FA (20:3n-3, eicosapentaenoic acid-EPA, 22:5n-3, and docosahexaenoic acid-DHA, and some of the LNA was stored in the liver. LNA, EPA and DHA concentrations (mg/g total lipids from 0 days for up 56 days increased from 1.29 to 18.90 (LNA, 0.20 to 18.90 (EPA and 41.26 to 99.17 (DHA.The concentration of n-3 FA in the livers varied with the duration of the LO diet. During LO feed, n-6 FA concentration fell and n-3 FA concentration rose through the experimental period.

  2. Improvement in Dissolution Rate of Cefuroxime Axetil by using Poloxamer 188 and Neusilin US2

    Directory of Open Access Journals (Sweden)

    J Sruti

    2013-01-01

    Full Text Available A combination of fusion and surface adsorption techniques was used to enhance the dissolution rate of cefuroxime axetil. Solid dispersions of cefuroxime axetil were prepared by two methods, namely fusion method using poloxamer 188 alone and combination of poloxamer 188 and Neusilin US2 by fusion and surface adsorption method. Solid dispersions were evaluated for solubility, phase solubility, flowability, compressibility, Kawakita analysis, Fourier transform-infrared spectra, differential scanning calorimetry, powder X-ray diffraction study, in vitro drug release, and stability study. Solubility studies showed 12- and 14-fold increase in solubility for solid dispersions by fusion method, and fusion and surface adsorption method, respectively. Phase solubility studies showed negative values for poloxamer 188 at various concentrations (0, 0.25, 0.5, 0.75 and 1% indicating spontaneous nature of solubilisation. Fourier transform-infrared spectra and differential scanning calorimetry spectra showed that drug and excipients are compatible with each other. Powder X-ray diffraction study studies indicated that presence of Neusilin US2 is less likely to promote the reversion of the amorphous cefuroxime axetil to crystalline state. In vitro dissolution studies, T50% and mean dissolution time have shown better dissolution rate for solid dispersions by fusion and surface adsorption method. Cefuroxime axetil release at 15 min (Q15 and DE15 exhibited 23- and 20-fold improvement in dissolution rate. The optimized solid dispersion formulation was stable for 6 months of stability study as per ICH guidelines. The stability was ascertained from drug content, in vitro dissolution, Fourier transform-infrared spectra and differential scanning calorimetry study. Hence, this combined approach of fusion and surface adsorption can be used successfully to improve the dissolution rate of poorly soluble biopharmaceutical classification system class II drug cefuroxime axetil.

  3. Chitosan-clodronate nanoparticles loaded in poloxamer gel for intra-articular administration.

    Science.gov (United States)

    Russo, E; Gaglianone, N; Baldassari, S; Parodi, B; Croce, I; Bassi, A M; Vernazza, S; Caviglioli, G

    2016-07-01

    This work was based on the study of an intra-articular delivery system constituted by a poloxamer gel vehiculating clodronate in chitosan nanoparticles. This system has been conceived to obtain a specific and controlled release of clodronate in the joints to reduce the arthritis rheumatoid degenerative effect. Clodronate (CLO) is a first-generation bisphosphonate with anti-inflammatory properties, inhibiting the cytokine and NO secretion from macrophages, therefore causing apoptosis in these cells. This is related to its ability to be metabolized by cells and converted into a cytotoxic intermediate as a non-hydrolysable analogue of ATP. Chitosan (CHI) was used to develop nanosystems, by ionotropic gelation induced by clodronate itself. A fractional factorial experimental design allowed us to obtain nanoparticles, the diameter of which ranged from 200 to 300nm. Glutaraldehyde was used to increase nanoparticle stability and modify the drug release profile. The zeta potential value of crosslinked nanopaparticles was 21.0mV±1.3, while drug loading was 31.0%±5.4 w/w; nanoparticle yield was 18.2%±1.8 w/w, the encapsulation efficiency was 48.8%±9.9 w/w. Nanoparticles were homogenously loaded in a poloxamer sol, and the drug delivery system is produced in-situ after local administration, when sol become gel at physiological temperature. The properties of poloxamer gels containing CHI-CLO nanoparticles, such as viscosity, gelation temperature and drug release properties, were evaluated. In vitro studies were conducted to evaluate the effects of these nanoparticles on a human monocytic cell line (THP1). The results showed that this drug delivery system is more efficient, with respect to the free drug, to counteract the inflammatory process characteristic of several degenerative diseases.

  4. The effect of APF-incorporated phosphoric acid etchant on shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Behnam Khosravanifard

    2011-01-01

    Full Text Available Background: The aim of this study was to evaluate the effect of adding acidulated phosphate fluoride (APF to phosphoric acid etchant on shear bond strength (SBS and adhesive remnant index (ARI of orthodontic brackets bonded to etched teeth. Methods: In this in vitro experimental study, 40 human premolars were etched with 37% phosphoric acid solution (Dentsply blended with 0, 25%, 50%, and 75% fractions of 1.23% APF (Dentsply. The brackets (Mini Dyna Lock, 3M were bonded (Transbond XT, 3M and were subjected to 96 hours of 37°C incubation and thermocycling procedures (2000 cycles, 5-55°C, dwell time = 30 s. Then, they were debonded at 1-mm crosshead speed to measure the SBS. The ARI was estimated at 10× magnification. The data were analyzed using the tests one-way analysis of variance (ANOVA, Tukey, chi-square, one-sample t-test, and Spearman correlation. Results: The SBS of the groups control, 25%, 50%, and 75% APF were 11.90±2.72, 8.01±3.13, 5.40±2.51, and 3.27±2.01 MPa, respectively. Mean ARI scores of these groups were 2.4 (control, 4.3, 4.7, and 4.8, respectively. According to the Tukey′s test, only the mean SBS of the second group (25% was not different from the control group (P=0.091. Conclusion: Adding about 20-25% of 1.23% APF to the phosphoric acid etchant might considerably reduce the amount of residual adhesive, without compromising the SBS.

  5. Severe Controlled Hemorrhage Resuscitation with Small Volume Poloxamer 188 in Sedated Miniature Swine

    Science.gov (United States)

    2011-11-01

    most similar to the cur- rent small volume P188 study utilized anesthetized mongrel dogs given an injection of 1 ml kg−1 of a 5% pluronic F-68 (P188...in renal blood flow, considered to be a rheolog- ical effect of the pluronic F-68. In contrast to the present small volume P188 resuscitation study...Day SM, Metzger JM. Dys- trophic heart failure blocked by membrane sealant poloxamer. Nature 2005;436:1025–9. [11]. Justicz AG, Farnsworth WV

  6. Pharmacokinetics of butorphanol tartrate in a long-acting poloxamer 407 gel formulation administered to Hispaniolan Amazon parrots (Amazona ventralis).

    Science.gov (United States)

    Laniesse, Delphine; Guzman, David Sanchez-Migallon; Knych, Heather K; Smith, Dale A; Mosley, Cornelia; Paul-Murphy, Joanne R; Beaufrère, Hugues

    2017-06-01

    OBJECTIVE To determine pharmacokinetics of butorphanol tartrate incorporated into poloxamer 407 (P407) after SC administration to Hispaniolan Amazon parrots (Amazona ventralis). ANIMALS 11 adult Hispaniolan Amazon parrots (6 males and 5 females; 11 to 27 years old). PROCEDURES A sterile formulation of butorphanol in P407 (But-P407) 25% (percentage determined as [weight of P407/weight of diluent] × 100]) was created (8.3 mg/mL). Five preliminary experiments (2 birds/experiment) were performed to determine the ideal dose for this species. The formulation then was administered (12.5 mg/kg, SC) to 8 birds. Blood samples were collected before (time 0) and 0.08, 0.5, 1, 2, 4, 8, 12, and 24 hours after drug administration. Some birds were used more than once, with a washout period of ≥ 3 months between subsequent treatments. Butorphanol concentrations were quantitated by use of liquid chromatography-tandem mass spectrometry. Pharmacokinetic analysis was performed by use of noncompartmental analysis. RESULTS Maximal plasma butorphanol concentration was reached at 1.31 hours. Plasma concentrations of butorphanol remained > 100 ng/mL for > 3 hours (all birds) or > 4 hours (5/8 birds) but < 8 hours (all birds). Half-life of the terminal slope was 3.41 hours. No adverse effects were detected. CONCLUSIONS AND CLINICAL RELEVANCE Butorphanol was absorbed well from the But-P407 25% by Hispaniolan Amazon parrots, and absorption followed a pharmacokinetic profile compatible with a sustained-release drug. A dose of 12.5 mg/kg, SC, would theoretically provide analgesia for 4 to 8 hours. No adverse effects were detected. Studies on the pharmacodynamics of this formulation are necessary to confirm the degree and duration of analgesia.

  7. Synthesis of structured lipid enriched with omega fatty acids and sn-2 palmitic acid by enzymatic esterification and its incorporation in powdered infant formula.

    Science.gov (United States)

    Nagachinta, Supakana; Akoh, Casimir C

    2013-05-08

    Structured lipid (SL) enriched with arachidonic (ARA) and docosahexaenoic (DHA) acids was produced from tripalmitin using Lipozyme TL IM. The effects of acyl donors, that is, free fatty acids vs fatty acid ethyl esters, on the reactions were compared. The highest total incorporation of ARA and DHA was obtained when the reaction continued for 24 h, at a substrate mole ratio of 9, using free fatty acids as acyl donors (acidolysis). The SL prepared by a large-scale acidolysis reaction contained 17.69 ± 0.09% total ARA, 10.75 ± 0.15% total DHA, and 48.53 ± 1.40% sn-2 palmitic acid. SL thermograms exhibited multiple peaks indicating complexity of the triacylglycerol (TAG) distribution. RP-HPLC analysis of SL revealed nine of 26 TAG molecular species that were similar to those of human milk fat. Powdered infant formulas containing the SL were prepared by wet-mixing/spray-drying and dry-blending methods. Formula prepared with microencapsulated SL and the dry-blending method had better oxidative stability and color quality.

  8. Plasma incorporation, apparent retroconversion and β-oxidation of 13C-docosahexaenoic acid in the elderly

    Directory of Open Access Journals (Sweden)

    Brenna J Thomas

    2011-01-01

    Full Text Available Abstract Background Higher fish or higher docosahexaenoic acid (DHA intake normally correlates positively with higher plasma DHA level, but recent evidence suggests that the positive relationship between intake and plasma levels of DHA is less clear in the elderly. Methods We compared the metabolism of 13C-DHA in six healthy elderly (mean - 77 y old and six young adults (mean - 27 y old. All participants were given a single oral dose of 50 mg of uniformly labelled 13C-DHA. Tracer incorporation into fatty acids of plasma triglycerides, free fatty acids, cholesteryl esters and phospholipids, as well as apparent retroconversion and β-oxidation of 13C-DHA were evaluated 4 h, 24 h, 7d and 28d later. Results Plasma incorporation and β-oxidation of 13C-DHA reached a maximum within 4 h in both groups, but 13C-DHA was transiently higher in all plasma lipids of the elderly 4 h to 28d later. At 4 h post-dose, 13C-DHA β-oxidation was 1.9 times higher in the elderly, but over 7d, cumulative β-oxidation of 13C-DHA was not different in the two groups (35% in the elderly and 38% in the young. Apparent retroconversion of 13C-DHA was well below 10% of 13C-DHA recovered in plasma at all time points, and was 2.1 times higher in the elderly 24 h and 7d after tracer intake. Conclusions We conclude that 13C-DHA metabolism changes significantly during healthy aging. Since DHA is a potentially important molecule in neuro-protection, these changes may be relevant to the higher vulnerability of the elderly to cognitive decline.

  9. Synthesis and Site-Specific Incorporation of Red-Shifted Azobenzene Amino Acids into Proteins.

    Science.gov (United States)

    John, Alford A; Ramil, Carlo P; Tian, Yulin; Cheng, Gang; Lin, Qing

    2015-12-18

    A series of red-shifted azobenzene amino acids were synthesized in moderate-to-excellent yields via a two-step procedure in which tyrosine derivatives were first oxidized to the corresponding quinonoidal spirolactones followed by ceric ammonium nitrate-catalyzed azo formation with the substituted phenylhydrazines. The resulting azobenzene-alanine derivatives exhibited efficient trans/cis photoswitching upon irradiation with a blue (448 nm) or green (530 nm) LED light. Moreover, nine superfolder green fluorescent protein (sfGFP) mutants carrying the azobenzene-alanine analogues were expressed in E. coli in good yields via amber codon suppression with an orthogonal tRNA/PylRS pair, and one of the mutants showed durable photoswitching with the LED light.

  10. Incorporation of lutein and docosahexaenoic acid from dietary microalgae into the retina in quail.

    Science.gov (United States)

    Schnebelen-Berthier, Coralie; Acar, Niyazi; Pouillart, Philippe; Thabuis, Clementine; Rodriguez, Bertrand; Depeint, Flore; Clerc, Elise; Mathiaud, Adeline; Bourdillon, Anne; Baert, Blandine; Bretillon, Lionel; Lecerf, Jean-Michel

    2015-03-01

    Lutein and docosahexaenoic acid (DHA) are associated with the prevention of age-related macular degeneration (AMD). Since microalgae are potent natural sources of these nutrients, their nutritional value should be evaluated based on the bioavailability of lutein and DHA for the retina via the plasmatic compartment. In this study, quail were fed for 5 months either with a diet supplemented or deprived with microalgae rich in lutein and DHA. In the microalgae-fed group, the retinal concentrations of lutein and zeaxanthin gradually increased whereas in plasma, these compounds started to increase from the first month of supplementation. We also observed a significant increase in retinal and plasmatic levels of DHA in the microalgae-fed group. In conclusion, the plasmatic and retinal contents of lutein and DHA were significantly increased in quail fed with lutein- and DHA-rich microalgae. Food fortification with microalgae may be an innovative way to increase lutein and DHA consumption in humans.

  11. Remodelling of the Vibrio cholerae membrane by incorporation of exogenous fatty acids from host and aquatic environments.

    Science.gov (United States)

    Giles, David K; Hankins, Jessica V; Guan, Ziqiang; Trent, M Stephen

    2011-02-01

    The Gram-negative bacteria Vibrio cholerae poses significant public health concerns by causing an acute intestinal infection afflicting millions of people each year. V. cholerae motility, as well as virulence factor expression and outer membrane protein production, has been shown to be affected by bile. The current study examines the effects of bile on V. cholerae phospholipids. Bile exposure caused significant alterations to the phospholipid profile of V. cholerae but not of other enteric pathogens. These changes consisted of a quantitative increase and migratory difference in cardiolipin, decreases in phosphatidylglycerol and phosphatidylethanolamine, and the dramatic appearance of an unknown phospholipid determined to be lyso-phosphatidylethanolamine. Major components of bile were not responsible for the observed changes, but long-chain polyunsaturated fatty acids, which are minor components of bile, were shown to be incorporated into phospholipids of V. cholerae. Although the bile-induced phospholipid profile was independent of the V. cholerae virulence cascade, we identified another relevant environment in which V. cholerae assimilates unique fatty acids into its membrane phospholipids - marine sediment. Our results suggest that Vibrio species possess unique machinery conferring the ability to take up a wider range of exogenous fatty acids than other enteric bacteria. © 2010 Blackwell Publishing Ltd.

  12. Multiplex Immunoassay Platforms Based on Shape-Coded Poly(ethylene glycol Hydrogel Microparticles Incorporating Acrylic Acid

    Directory of Open Access Journals (Sweden)

    Won-Gun Koh

    2012-06-01

    Full Text Available A suspension protein microarray was developed using shape-coded poly(ethylene glycol (PEG hydrogel microparticles for potential applications in multiplex and high-throughput immunoassays. A simple photopatterning process produced various shapes of hydrogel micropatterns that were weakly bound to poly(dimethylsiloxane (PDMS-coated substrates. These micropatterns were easily detached from substrates during the washing process and were collected as non-spherical microparticles. Acrylic acids were incorporated into hydrogels, which could covalently immobilize proteins onto their surfaces due to the presence of carboxyl groups. The amount of immobilized protein increased with the amount of acrylic acid due to more available carboxyl groups. Saturation was reached at 25% v/v of acrylic acid. Immunoassays with IgG and IgM immobilized onto hydrogel microparticles were successfully performed with a linear concentration range from 0 to 500 ng/mL of anti-IgG and anti-IgM, respectively. Finally, a mixture of two different shapes of hydrogel microparticles immobilizing IgG (circle and IgM (square was prepared and it was demonstrated that simultaneous detection of two different target proteins was possible without cross-talk using same fluorescence indicator because each immunoassay was easily identified by the shapes of hydrogel microparticles.

  13. Fluorescence turn-on recognition of chiral amino acids using dye incorporated β-CD functionalized AuNPs assembly

    Energy Technology Data Exchange (ETDEWEB)

    Aswathy, B., E-mail: aswathybv@gmail.com; Sony, G., E-mail: emailtosony@gmail.com

    2014-10-15

    An assembly of dye incorporated β-cyclodextrin (βCD) functionalized AuNPs for the fluorescent probing of chiral amino acids is presented. Gold nanoparticles (AuNPs) possessing a high extinction coefficient function can be used as excellent fluorescent quenchers in AuNP–fluorophore system. Inclusion of fluorescein (FL) into β-cyclodextrin (βCD) makes energy transfer to occur through the donor and quencher nearby. This energy transfer switches off by virtue of the analyte induced release of FL from β-CD cavity, which results in the fluorescence recovery of the quenched dye. Analysis suggests that the assembly of AuNPs–βCDs–FL is effective as a turn-on fluorescent probe for the chiroselective optical discrimination between D,L-tryptophan, D,L-phenyl alanine and D,L-tyrosine. The detection limits for analyzing L-tryptophan, L-phenyl alanine and L-tyrosine were found to be 0.59, 1.2 and 1.5 μM respectively. - Highlights: • Fluorescence quenching AuNP–βCD–dye assembly via energy transfer. • Energy transfer from dye to AuNPs is a SET process. • Fluorescence turn-on detection of amino acids by the competitive binding method. • Chiroselective discrimination between enantiomeric amino acids.

  14. Comparison of isotope-labeled amino acid incorporation rates (CILAIR) provides a quantitative method to study tissue secretomes.

    Science.gov (United States)

    Roelofsen, Han; Dijkstra, Martijn; Weening, Desiree; de Vries, Marcel P; Hoek, Annemieke; Vonk, Roel J

    2009-02-01

    Adipose tissue is an endocrine organ involved in regulation of whole-body energy metabolism via storage of lipids and secretion of various peptide hormones (adipokines). We previously characterized the adipose tissue secretome and showed that [(13)C]lysine incorporation into secreted proteins can be used to determine the origin of identified proteins. In the present study we determined the effect of insulin on the secretome by comparing incorporation rates of (13)C-labeled lysine in the presence and absence of insulin. Human visceral adipose tissue from one patient was divided over six dishes. After subsequent washes to remove serum proteins, [(13)C]lysine-containing medium was added. Three dishes also received 60 nm insulin. The other three were controls. After 72 h of culture, media were collected and processed separately, involving concentration by ultrafiltration and fractionation by SDS-PAGE followed by in-gel digestion of excised bands and LC-MS/MS analyses. The obtained spectra were used for database searching and calculation of heavy/light ratios. The three control data sets shared 342 proteins of which 156 were potentially secreted and contained label. The three insulin-derived data sets shared 361 proteins of which 141 were potentially secreted and contained label. After discarding secreted proteins with very low label incorporation, 121 and 113 proteins remained for control and insulin data sets, respectively. The average coefficient of variation for control triplicates was 10.0% and for insulin triplicates was 18.3%. By comparing heavy/light ratios in the absence and presence of insulin we found 24 up-regulated proteins and four down-regulated proteins, and 58 proteins showed no change. Proteins involved in the endoplasmic reticulum stress response and in extracellular matrix remodeling were up-regulated by insulin. In conclusion, comparison of isotope-labeled amino acid incorporation rates (CILAIR) allows quantitative assessment of changes in protein

  15. A micelle-like structure of poloxamer-methotrexate conjugates as nanocarrier for methotrexate delivery.

    Science.gov (United States)

    Ren, Jin; Fang, Zhengjie; Yao, Li; Dahmani, Fatima Zohra; Yin, Lifang; Zhou, Jianping; Yao, Jing

    2015-06-20

    The purpose of this study was to develop a novel featured and flexible methotrexate (MTX) formulation, in which MTX was physically entrapped and chemically conjugated in the same drug delivery system. A series of poloxamer-MTX (p-MTX) conjugates was synthesized, wherein MTX was grafted to poloxamer through an ester bond. p-MTX conjugates could self-assemble into micelle-like structures in aqueous environment and the MTX end was in the inner-core of micelles. Moreover, free MTX could be physically entrapped into p-MTX micelles hydrophobic core region to increase the total drug loading. Importantly, the resulting MTX-loaded p-MTX micelles showed a biphasic release of MTX, with a relative fast release of the entrapped MTX (about 6-7h) followed by a sustained release of the conjugated MTX. The pharmacokinetics study showed that the mean residence time (MRT) was extended in the case of MTX-loaded p-MTX micelles, indicating a delayed MTX elimination from the bloodstream and prolonged in vivo residence time. Besides, the area under curve (AUC) of MTX-loaded p-MTX micelles was greater than free MTX, indicating a drug bioavailability improvement. Overall, MTX-loaded p-MTX micelles might be a promising nanosized drug delivery system for the cancer therapy.

  16. Baicalein and hydroxypropyl-γ-cyclodextrin complex in poloxamer thermal sensitive hydrogel for vaginal administration.

    Science.gov (United States)

    Zhou, Qiuna; Zhong, Lin; Wei, Xiaohui; Dou, Wei; Chou, Guixin; Wang, Zhengtao

    2013-09-15

    The present study aimed to prepare a chemically and physically stable formulation of baicalein (Ba) in an in situ thermally sensitive hydrogel for vaginal administration. An inclusion complex of Ba and hydroxypropyl-γ-cyclodextrin (HP-γ-CD) was first developed to increase the stability and solubility of Ba in an aqueous solution. The formation of the Ba-HP-γ-CD complex was characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray powder diffractometry (XRPD). Poloxamers 407, 188 (P407, P188), sodium alginate (SA), hydroxypropylmethylcellulose (HPMC), and benzalkonium bromide were mixed to obtain a hydrogel with an appropriate gelation temperature for vaginal use. Among the formulations examined, P407/Ba-HP-γ-CD/HPMC/P188/benzalkonium bromide (18/0.96/0.5/4.0/0.02%) represented the appropriate gelation temperature and acceptable drug release rate at the administration site. Release of Ba-HP-γ-CD from the poloxamer hydrogel followed Peppas equation, which suggests that it occurred through coupled corrosion-diffusion mechanism, and the corrosion-release curve showed that corrosion was the primary mode of release. In animal study, treatment by using Ba-HP-γ-CD thermosensitive hydrogel could produce a restoration of damaged tissues. Thermosensitive hydrogel formulation of the Ba-HP-γ-CD complex appears to be a promising treatment for cervicitis.

  17. Control over Particle Size Distribution by Autoclaving Poloxamer-Stabilized Trimyristin Nanodispersions.

    Science.gov (United States)

    Göke, Katrin; Roese, Elin; Arnold, Andreas; Kuntsche, Judith; Bunjes, Heike

    2016-09-06

    Lipid nanoparticles are under investigation as delivery systems for poorly water-soluble drugs. The particle size in these dispersions strongly influences important pharmaceutical properties like biodistribution and drug loading capacity; it should be below 500 nm for direct injection into the bloodstream. Consequently, small particles with a narrow particle size distribution are desired. Hitherto, there are, however, only limited possibilities for the preparation of monodisperse, pharmaceutically relevant dispersions. In this work, the effect of autoclaving at 121 °C on the particle size distribution of lipid nanoemulsions and -suspensions consisting of the pharmaceutically relevant components trimyristin and poloxamer 188 was studied. Additionally, the amount of emulsifier needed to stabilize both untreated and autoclaved particles was assessed. In our study, four dispersions of mean particle sizes from 45 to 150 nm were prepared by high-pressure melt homogenization. The particle size distribution before and after autoclaving was characterized using static and dynamic light scattering, differential scanning calorimetry, and transmission electron microscopy. Asymmetrical flow field-flow fractionation was used for particle size distribution analyses and for the determination of free poloxamer 188. Upon autoclaving, the mean particle size increased to up to 200 nm, but not proportionally to the initial size. At the same time, the particle size distribution width decreased remarkably. Heat treatment thus seems to be a promising approach to achieve the desired narrow particle size distribution of such dispersions. Related to the lipid content, suspension particles needed more emulsifier for stabilization than emulsion droplets, and smaller particles more than larger ones.

  18. Kinetics of the incorporation of dietary fatty acids into serum cholesteryl esters, erythrocyte membranes, and adipose tissue: an 18-month controlled study.

    NARCIS (Netherlands)

    Katan, M.B.; Deslypere, J.P.; Birgelen, van A.P.J.M.; Wennekes-Penders, M.M.H.; Zegwaard, M.J.

    1997-01-01

    Tissue levels of n-3 fatty acids reflect dietary intake, but quantitative data about rate of incorporation and levels as a function of intake are scarce. We fed 58 men 0, 3, 6, or 9 g/d of fish oil for 12 months and monitored fatty acids in serum cholesteryl esters, erythrocytes, and subcutaneous fa

  19. Incorporation of preservatives in polylactic acid films for inactivating E. coli O157:H7 and extending microbiological shelf-life of strawberry puree

    Science.gov (United States)

    Antimicrobial films of polylactic acid polymer incorporated with nisin, Ethylenediaminetetraacetic acid (EDTA), sodium benzoate (SB), potassium sorbate (PS) and their combination were developed and their antimicrobial effects on the inactivation of Escherichia coli O157:H7 and natural background mic...

  20. Incorporation of hyaluronic acid into collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Tang Shunqing [Department of Biomedical Engineering, Jinan University, Guangzhou 510632 (China); Spector, Myron [Tissue Engineering, VA Boston Healthcare System, Boston, MA 02130 (United States)

    2007-09-15

    Hyaluronic acid (HA), a principal matrix molecule in many tissues, is present in high amounts in articular cartilage. HA contributes in unique ways to the physical behavior of the tissue, and has been shown to have beneficial effects on chondrocyte activity. The goal of this study was to incorporate graduated amounts of HA into type I collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis in vitro. The results demonstrated that the amount of contraction of HA/collagen scaffolds by adult canine articular chondrocytes increased with the HA content of the scaffolds. The greatest amount of chondrogenesis after two weeks was found in the scaffolds which had undergone the most contraction. HA can play a useful role in adjusting the mechanical behavior of tissue engineering scaffolds and chondrogenesis in chondrocyte-seeded scaffolds.

  1. Oxidation and sensing of ascorbic acid and dopamine on self-assembled gold nanoparticles incorporated within polyaniline film

    Science.gov (United States)

    Chu, Wenya; Zhou, Qun; Li, Shuangshuang; Zhao, Wei; Li, Na; Zheng, Junwei

    2015-10-01

    Electrochemical biosensors based on conducting polymers incorporated with metallic nanoparticles can greatly enhance sensitivity and selectivity. Herein, we report a facile fabrication approach for polyaniline (PAN) incorporated with a gold nanoparticle (AuNP) composite electrode by electrodeposition of PAN on a self-assembled AuNP layer on the surface of an indium tin oxide electrode. The resulting AuNP/PAN composite electrode exhibits a remarkable synergistic effect on the electrocatalytic oxidation of ascorbic acid (AA) and dopamine (DA). It is demonstrated that the oxidation reaction of AA mainly occurs at AuNPs inside the PAN film as the ascorbate anions are doped into the polymer during the oxidation of the PAN film. Conversely, the oxidation of positively charged DA may only take place at the PAN/solution interface. The different mechanisms of the electrode reactions result in the oxidation of AA and DA occurring at different potentials. As a result, the AuNP/PAN composite electrode can be employed to simultaneously detect AA and DA with a good linear range, high sensitivity, and low detection limit.

  2. Antitumor Activity of Doxorubicin-Loaded Carbon Nanotubes Incorporated Poly(Lactic-Co-Glycolic Acid) Electrospun Composite Nanofibers

    Science.gov (United States)

    Yu, Yuan; Kong, Lijun; Li, Lan; Li, Naie; Yan, Peng

    2015-08-01

    The drug-loaded composite electrospun nanofiber has attracted more attention in biomedical field, especially in cancer therapy. In this study, a composite nanofiber was fabricated by electrospinning for cancer treatment. Firstly, the carbon nanotubes (CNTs) were selected as carriers to load the anticancer drug—doxorubicin (DOX) hydrochloride. Secondly, the DOX-loaded CNTs (DOX@CNTs) were incorporated into the poly(lactic-co-glycolic acid) (PLGA) nanofibers via electrospinning. Finally, a new drug-loaded nanofibrous scaffold (PLGA/DOX@CNTs) was formed. The properties of the prepared composite nanofibrous mats were characterized by various techniques. The release profiles of the different DOX-loaded nanofibers were measured, and the in vitro antitumor efficacy against HeLa cells was also evaluated. The results showed that DOX-loaded CNTs can be readily incorporated into the nanofibers with relatively uniform distribution within the nanofibers. More importantly, the drug from the composite nanofibers can be released in a sustained and prolonged manner, and thereby, a significant antitumor efficacy in vitro is obtained. Thus, the prepared composite nanofibrous mats are a promising alternative for cancer treatment.

  3. [A dyslipidemia animal model induced by poloxamer 407 in golden hamsters and pilot study on the mechanism].

    Science.gov (United States)

    Liu, Quan; Liu, Shuai-nan; Li, Lin-yi; Chen, Zhi-yu; Lei, Lei; Zhang, Ning; Shen, Zhu-fang

    2011-04-01

    The aim of this study is to establish a simple and stable model like poloxamer 407 (P-407)-induced dyslipidemia of golden hamster model, and investigate the mechanism of lipid metabolism disturbance in this model. PPARalpha agonist and HMG-CoA reductase inhibitor were administrated to validate the efficacy on regulating lipid metabolism in the dyslipidemia golden hamster model. Six weeks male golden hamsters were chosen to inject P-407 intraperitoneally at a bolus dose of 300 mg x kg(-1), an intermittent injection at a dose of 200 mg x kg(-1) every 72 hours after the bolus. The results showed that P-407-induced golden hamster model characterized as increased serum triglyceride (TG), total cholesterol (TC), free cholesterol (free-CHO), cholesteryl ester (CE), free fatty acids (FFA) and apoB levels, and the hyperlipidemia state maintained at a stable level persistently. Meanwhile, augmented malondialdehyde (MDA) and nitric oxide (NO) level was observed. LCAT and SR-B I mRNA levels in liver of model group were down-regulated (expression ratio is 0.426; 0.783), while HMG-CoA reductase mRNA level was up-regulated (expression ratio is 1.493) compared with those of the normal group. The serum cholesterol and triglyceride levels were significantly lower in P-407-induced dyslipidemia hamster model after treated with atorvastatin (Ato) at a dose of 50 mg x kg(1) or fenofibrate (Fen) at 100 mg x kg(-1) for two weeks. These findings suggest that serum lipid distribution in dyslipidemia golden hamster is similar to that of human, and which may be relevant to the disturbance of the enzymes expression involved in lipid metabolism in liver. Results obtained from this study support the concept that dyslipidemia golden hamster may be an adequate animal model to evaluate the efficacy of lipid-lowering agents.

  4. Maximising metal ions flux across a microdialysis membrane by incorporating poly-L-aspartic acid, poly-L-histidine, 8-hydroxyquinoline and ethylenediaminetetraacetic acid in the perfusion liquid

    Energy Technology Data Exchange (ETDEWEB)

    Mogopodi, Dikabo [University of Botswana, Department of Chemistry, Private Bag UB 00704, Gaborone (Botswana); Torto, Nelson [University of Botswana, Department of Chemistry, Private Bag UB 00704, Gaborone (Botswana)]. E-mail: torton@mopipi.ub.bw

    2005-04-08

    This paper presents a study of quiescent microdialysis sampling of Cr{sup 3+}, Cu{sup 2+}, Ni{sup 2+} and Pb{sup 2+} involving the incorporation of poly-L-aspartic acid, poly-L-histidine, 8-hydroxyquinoline (8-HQ) and ethylenediaminetetraacetic acid (EDTA), in the perfusion liquid as an approach to maximise metal analyte flux across the microdialysis membrane. These chelating agents were individually optimised with respect to microdialysis recovery and subsequently combined in the perfusion liquid. A combination of 20% (w/v) poly-L-histidine, 0.032% (w/v) poly-L-aspartic acid and 1 mM 8-HQ achieved microdialysis recovery up to 90%. Since 1 mM EDTA achieved recoveries greater than 80% for all metals understudy, EDTA was not combined with any of the chelating agents. Under the optimal conditions of maximum metal ion flux across the microdialysis membrane, metal ions from natural and wastewater were sampled and analysed with an electrothermal atomic absorption spectrometer equipped with a Zeeman background corrector. Results showed higher concentrations of detected metal ions after microdialysis sampling compared to direct detection without sample clean-up. Incorporation of chelating agents in the microdialysis perfusion liquid enhanced metal ions recovery in real samples and achieved enrichment factors of up to 42. The study demonstrated that combining chelating agents is a good approach towards maximising metal flux across the dialysis membrane. Given that recoveries between 80 and 90% were achieved under quiescent microdialysis sampling conditions, these findings are an important development for in vivo diagnostic sampling of metal ions.

  5. Metabolism of Glycerol, Glucose, and Lactate in the Citric Acid Cycle Prior to Incorporation into Hepatic Acylglycerols*

    Science.gov (United States)

    Jin, Eunsook S.; Sherry, A. Dean; Malloy, Craig R.

    2013-01-01

    During hepatic lipogenesis, the glycerol backbone of acylglycerols originates from one of three sources: glucose, glycerol, or substrates passing through the citric acid cycle via glyceroneogenesis. The relative contribution of each substrate source to glycerol in rat liver acylglycerols was determined using 13C-enriched substrates and NMR. Animals received a fixed mixture of glucose, glycerol, and lactate; one group received [U-13C6]glucose, another received [U-13C3]glycerol, and the third received [U-13C3]lactate. After 3 h, the livers were harvested to extract fats, and the glycerol moiety from hydrolyzed acylglycerols was analyzed by 13C NMR. In either fed or fasted animals, glucose and glycerol provided the majority of the glycerol backbone carbons, whereas the contribution of lactate was small. In fed animals, glucose contributed >50% of the total newly synthesized glycerol backbone, and 35% of this contribution occurred after glucose had passed through the citric acid cycle. By comparison, the glycerol contribution was ∼40%, and of this, 17% of the exogenous glycerol passed first through the cycle. In fasted animals, exogenous glycerol became the major contributor to acylglycerols. The contribution from exogenous lactate did increase in fasted animals, but its overall contribution remained small. The contributions of glucose and glycerol that had passed through the citric acid cycle first increased in fasted animals from 35 to 71% for glucose and from 17 to 24% for glycerol. Thus, a substantial fraction from both substrate sources passed through the cycle prior to incorporation into the glycerol moiety of acylglycerols in the liver. PMID:23572519

  6. Metabolism of glycerol, glucose, and lactate in the citric acid cycle prior to incorporation into hepatic acylglycerols.

    Science.gov (United States)

    Jin, Eunsook S; Sherry, A Dean; Malloy, Craig R

    2013-05-17

    During hepatic lipogenesis, the glycerol backbone of acylglycerols originates from one of three sources: glucose, glycerol, or substrates passing through the citric acid cycle via glyceroneogenesis. The relative contribution of each substrate source to glycerol in rat liver acylglycerols was determined using (13)C-enriched substrates and NMR. Animals received a fixed mixture of glucose, glycerol, and lactate; one group received [U-(13)C6]glucose, another received [U-(13)C3]glycerol, and the third received [U-(13)C3]lactate. After 3 h, the livers were harvested to extract fats, and the glycerol moiety from hydrolyzed acylglycerols was analyzed by (13)C NMR. In either fed or fasted animals, glucose and glycerol provided the majority of the glycerol backbone carbons, whereas the contribution of lactate was small. In fed animals, glucose contributed >50% of the total newly synthesized glycerol backbone, and 35% of this contribution occurred after glucose had passed through the citric acid cycle. By comparison, the glycerol contribution was ~40%, and of this, 17% of the exogenous glycerol passed first through the cycle. In fasted animals, exogenous glycerol became the major contributor to acylglycerols. The contribution from exogenous lactate did increase in fasted animals, but its overall contribution remained small. The contributions of glucose and glycerol that had passed through the citric acid cycle first increased in fasted animals from 35 to 71% for glucose and from 17 to 24% for glycerol. Thus, a substantial fraction from both substrate sources passed through the cycle prior to incorporation into the glycerol moiety of acylglycerols in the liver.

  7. Evaluation of a novel thermosensitive heparin-poloxamer hydrogel for improving vascular anastomosis quality and safety in a rabbit model.

    Directory of Open Access Journals (Sweden)

    Ying-Zheng Zhao

    Full Text Available Despite progress in the design of advanced surgical techniques, stenosis recurs in a large percentage of vascular anastomosis. In this study, a novel heparin-poloxamer (HP hydrogel was designed and its effects for improving the quality and safety of vascular anastomosis were studied. HP copolymer was synthesized and its structure was confirmed by Fourier transform infrared spectroscopy (FTIR and nuclear magnetic resonance spectroscopy ((1H-NMR. Hydrogels containing HP were prepared and their important characteristics related to the application in vascular anastomosis including gelation temperature, rheological behaviour and micromorphology were measured. Vascular anastomosis were performed on the right common carotid arteries of rabbits, and the in vivo efficiency and safety of HP hydrogel to achieve vascular anastomosis was verified and compared with Poloxamer 407 hydrogel and the conventional hand-sewn method using Doppler ultrasound, CT angiograms, scanning electron microscopy (SEM and histological technique. Our results showed that HP copolymer displayed special gel-sol-gel phase transition behavior with increasing temperature from 5 to 60 °C. HP hydrogel prepared from 18 wt% HP solution had a porous sponge-like structure, with gelation temperature at approximately 38 °C and maximum elastic modulus at 10,000 Pa. In animal studies, imaging and histological examination of rabbit common jugular artery confirmed that HP hydrogel group had similar equivalent patency, flow and burst strength as Poloxamer 407 group. Moreover, HP hydrogel was superior to poloxamer 407 hydrogel and hand-sewn method for restoring the functions and epithelial structure of the broken vessel junctions after operation. By combining the advantages of heparin and poloxamer 407, HP hydrogel holds high promise for improving vascular anastomosis quality and safety.

  8. Preparation and characterization of electrospun PLCL/Poloxamer nanofibers and dextran/gelatin hydrogels for skin tissue engineering.

    Directory of Open Access Journals (Sweden)

    Jian-feng Pan

    Full Text Available In this study, two different biomaterials were fabricated and their potential use as a bilayer scaffold for skin tissue engineering applications was assessed. The upper layer biomaterial was a Poly(ε-caprolactone-co-lactide/Poloxamer (PLCL/Poloxamer nanofiber membrane fabricated using electrospinning technology. The PLCL/Poloxamer nanofibers (PLCL/Poloxamer, 9/1 exhibited strong mechanical properties (stress/strain values of 9.37 ± 0.38 MPa/187.43 ± 10.66% and good biocompatibility to support adipose-derived stem cells proliferation. The lower layer biomaterial was a hydrogel composed of 10% dextran and 20% gelatin without the addition of a chemical crosslinking agent. The 5/5 dextran/gelatin hydrogel displayed high swelling property, good compressive strength, capacity to present more than 3 weeks and was able to support cells proliferation. A bilayer scaffold was fabricated using these two materials by underlaying the nanofibers and casting hydrogel to mimic the structure and biological function of native skin tissue. The upper layer membrane provided mechanical support in the scaffold and the lower layer hydrogel provided adequate space to allow cells to proliferate and generate extracellular matrix. The biocompatibility of bilayer scaffold was preliminarily investigated to assess the potential cytotoxicity. The results show that cell viability had not been affected when cocultured with bilayer scaffold. As a consequence, the bilayer scaffold composed of PLCL/Poloxamer nanofibers and dextran/gelatin hydrogels is biocompatible and possesses its potentially high application prospect in the field of skin tissue engineering.

  9. Long-term effect of dietary α-linolenic acid or decosahexaenoic acid on incorporation of decosahexaenoic acid in membranes and its influence on rat heart in vivo

    OpenAIRE

    2007-01-01

    The present study was designed to evaluate whether long-term intake of dietary alpha-linolenic acid (ALA), supplied as whole grain-extruded linseed, can increase endogenous production of n-3 long-chain polyunsaturated fatty acids (FAs) in healthy adult rats and influence the heart rate (HR) and adrenergic response in the same way as docosahexaenoic acid (DHA)-rich diets. DHA enrichment was evaluated using FA analysis of tissue phospholipids after 8, 16, 24, and 32 wk of feeding in male Wistar...

  10. Prospects of In vivo Incorporation of Non-canonical Amino Acids for the Chemical Diversification of Antimicrobial Peptides

    Science.gov (United States)

    Baumann, Tobias; Nickling, Jessica H.; Bartholomae, Maike; Buivydas, Andrius; Kuipers, Oscar P.; Budisa, Nediljko

    2017-01-01

    The incorporation of non-canonical amino acids (ncAA) is an elegant way for the chemical diversification of recombinantly produced antimicrobial peptides (AMPs). Residue- and site-specific installation methods in several bacterial production hosts hold great promise for the generation of new-to-nature AMPs, and can contribute to tackle the ongoing emergence of antibiotic resistance in pathogens. Especially from a pharmacological point of view, desirable improvements span pH and protease resistance, solubility, oral availability and circulation half-life. Although the primary focus of this report is on ribosomally synthesized and post-translationally modified peptides (RiPPs), we have included selected cases of peptides produced by solid phase peptide synthesis to comparatively show the potential and impact of ncAA introduction. Generally speaking, the introduction of ncAAs in recombinant AMPs delivers novel levels of chemical diversification. Cotranslationally incorporated, they can take part in AMP biogenesis either through direction interaction with elements of the post-translational modification (PTM) machinery or as untargeted sites with unique physicochemical properties and chemical handles for further modification. Together with genetic libraries, genome mining and processing by PTM machineries, ncAAs present not a mere addition to this process, but a highly diverse pool of building blocks to significantly broaden the chemical space of this valuable class of molecules. This perspective summarizes new developments of ncAA containing peptides. Challenges to be resolved in order to reach large-scale pharmaceutical production of these promising compounds and prospects for future developments are discussed. PMID:28210246

  11. Docosahexaenoic Acid and Eicosapentaenoic Acid Did not Alter trans-10,cis-12 Conjugated Linoleic Acid Incorporation into Mice Brain and Eye Lipids.

    Science.gov (United States)

    Vemuri, Madhuri; Adkins, Yuriko; Mackey, Bruce E; Kelley, Darshan S

    2017-09-01

    trans 10,cis 12-CLA has been reported to alter fatty acid composition in several non-neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight-week-old, pathogen-free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12-CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration.

  12. Stability studies of As4S4 nanosuspension prepared by wet milling in Poloxamer 407.

    Science.gov (United States)

    Bujňáková, Zdenka; Dutková, Erika; Baláž, Matej; Turianicová, Erika; Baláž, Peter

    2015-01-15

    In this paper the stability of the arsenic sulfide (As4S4) nanosuspension prepared by wet milling in a circulation mill in the environment of copolymer Poloxamer 407 was studied. The obtained As4S4 particles in nanosuspension were of ∼ 100 nm in size. The influence of temperature and UV irradiation on the changes in physical and/or chemical properties was followed. Long-term stability was observed via particle size distribution and zeta potential measurements. Influence of UV irradiation was studied via UV-vis spectroscopy (UV-vis), photoluminicsence (PL) technique and Fourier transform infrared spectroscopy (FTIR) measurements. The best stability of the nanosuspension (24 weeks) was achieved when stored at 4°C and in the dark.

  13. Effect of methyl cellulose on gelation behavior and drug release from poloxamer based ophthalmic formulations.

    Science.gov (United States)

    Dewan, Mitali; Bhowmick, Biplab; Sarkar, Gunjan; Rana, Dipak; Bain, Mrinal Kanti; Bhowmik, Manas; Chattopadhyay, Dipankar

    2015-01-01

    The effect of weight average molecular weight (Mw) of methyl cellulose (MC) on the gelation behavior of Poloxamer 407 (PM) and in vitro release of Ketorolac Tromethamine (KT) from different ophthalmic formulations based on PM is examined. A drop of gelation temperature of PM is observed using MC of various M(w) by test tube tilting method, UV-vis spectroscopy, viscometry and rheometry. It is also observed that the viscosity and gel strength of all the formulations are increased with the increase in Mw of MC. PM with highest Mw of MC provides best drug release property among all the formulations. It is evident from this investigation that there is a distinct effect of M(w) of MC on the gelation behavior of PM as well as on the drug release profile of KT from PM-MC based ophthalmic formulations.

  14. Control over particle size distribution by autoclaving poloxamer-stabilized trimyristin nanodispersions

    DEFF Research Database (Denmark)

    Göke, Katrin; Roese, Elin; Arnold, Andreas

    2016-01-01

    into the bloodstream. Consequently, small particles with a narrow particle size distribution are desired. Hitherto, there are, however, only limited possibilities for the preparation of monodisperse, pharmaceutically relevant dispersions. In this work, the effect of autoclaving at 121 °C on the particle size...... distribution of lipid nanoemulsions and -suspensions consisting of the pharmaceutically relevant components trimyristin and poloxamer 188 was studied. Additionally, the amount of emulsifier needed to stabilize both untreated and autoclaved particles was assessed. In our study, four dispersions of mean particle...... sizes from 45 to 150 nm were prepared by high-pressure melt homogenization. The particle size distribution before and after autoclaving was characterized using static and dynamic light scattering, differential scanning calorimetry, and transmission electron microscopy. Asymmetrical flow field...

  15. Poloxamer-188 and citicoline provide neuronal membrane integrity and protect membrane stability in cortical spreading depression.

    Science.gov (United States)

    Yıldırım, Timur; Eylen, Alpaslan; Lule, Sevda; Erdener, Sefik Evren; Vural, Atay; Karatas, Hulya; Ozveren, Mehmet Faik; Dalkara, Turgay; Gursoy-Ozdemir, Yasemin

    2015-01-01

    Under pathological conditions such as brain trauma, subarachnoid hemorrhage and stroke, cortical spreading depression (CSD) or peri-infarct depolarizations contribute to brain damage in animal models of neurological disorders as well as in human neurological diseases. CSD causes transient megachannel opening on the neuronal membrane, which may compromise neuronal survival under pathological conditions. Poloxamer-188 (P-188) and citicoline are neuroprotectants with membrane sealing properties. The aim of this study is to investigate the effect of P-188 and citicoline on the neuronal megachannel opening induced by CSD in the mouse brain. We have monitored megachannel opening with propidium iodide, a membrane impermeable fluorescent dye and, demonstrate that P-188 and citicoline strikingly decreased CSD-induced neuronal PI influx in cortex and hippocampal dentate gyrus. Therefore, these agents may be providing neuroprotection by blocking megachannel opening, which may be related to their membrane sealing action and warrant further investigation for treatment of traumatic brain injury and ischemic stroke.

  16. Identification of the structure and origin of a thioacidolysis marker compound for ferulic acid incorporation into angiosperm lignins (and an indicator for cinnamoyl CoA reductase deficiency).

    Science.gov (United States)

    Ralph, John; Kim, Hoon; Lu, Fachuang; Grabber, John H; Leplé, Jean-Charles; Berrio-Sierra, Jimmy; Derikvand, Mohammad Mir; Jouanin, Lise; Boerjan, Wout; Lapierre, Catherine

    2008-01-01

    A molecular marker compound, derived from lignin by the thioacidolysis degradative method, for structures produced when ferulic acid is incorporated into lignin in angiosperms (poplar, Arabidopsis, tobacco), has been structurally identified as 1,2,2-trithioethyl ethylguaiacol [1-(4-hydroxy-3-methoxyphenyl)-1,2,2-tris(ethylthio)ethane]. Its truncated side chain and distinctive oxidation state suggest that it derives from ferulic acid that has undergone bis-8-O-4 (cross) coupling during lignification, as validated by model studies. A diagnostic contour for such structures is found in two-dimensional (13)C-(1)H correlated (HSQC) NMR spectra of lignins isolated from cinnamoyl CoA reductase (CCR)-deficient poplar. As low levels of the marker are also released from normal (i.e. non-transgenic) plants in which ferulic acid may be present during lignification, notably in grasses, the marker is only an indicator for CCR deficiency in general, but is a reliable marker in woody angiosperms such as poplar. Its derivation, together with evidence for 4-O-etherified ferulic acid, strongly implies that ferulic acid is incorporated into angiosperm lignins. Its endwise radical coupling reactions suggest that ferulic acid should be considered an authentic lignin precursor. Moreover, ferulic acid incorporation provides a new mechanism for producing branch points in the polymer. The findings sharply contradict those reported in a recent study on CCR-deficient Arabidopsis.

  17. PLGA implants: How Poloxamer/PEO addition slows down or accelerates polymer degradation and drug release.

    Science.gov (United States)

    Hamoudi-Ben Yelles, M C; Tran Tan, V; Danede, F; Willart, J F; Siepmann, J

    2017-03-08

    The aim of this study was to evaluate the impact of the addition of small amounts of hydrophilic polymers (Poloxamer 188 and PEO 200kDa) to PLGA-based implants loaded with prilocaine. Special emphasis was placed on the importance of the type of preparation technique: direct compression of milled drug-polymer powder blends versus compression of drug loaded microparticles (prepared by spray-drying). The implants were thoroughly characterized before and upon exposure to phosphate buffer pH7.4, e.g. using optical and scanning electron microscopy, X-ray diffraction, DSC and GPC. Interestingly, the addition of Poloxamer/PEO to the PLGA implants had opposite effects on the resulting drug release kinetics, depending on the type of preparation method: in the case of implants prepared by compression of milled drug-polymer powder blends, drug release was accelerated, whereas it was slowed down when the implants were prepared by compression of drug loaded PLGA microparticles. These phenomena could be explained by the swelling/disintegration behavior of the implants upon exposure to the release medium. Systems consisting of compressed microparticles remained intact and autocatalytic effects were of major importance. The presence of a hydrophilic polymer facilitated water penetration into these devices, slowing down PLGA degradation and drug release. In contrast, implants consisting of compressed drug-polymer powder blends rapidly (at least partially) disintegrated and autocatalysis was much less important. In these cases, the addition of a hydrophilic polymer facilitated ester bond cleavage, leading to accelerated PLGA degradation and drug release.

  18. Using NGF heparin-poloxamer thermosensitive hydrogels to enhance the nerve regeneration for spinal cord injury.

    Science.gov (United States)

    Zhao, Ying-Zheng; Jiang, Xi; Xiao, Jian; Lin, Qian; Yu, Wen-Ze; Tian, Fu-Rong; Mao, Kai-Li; Yang, Wei; Wong, Ho Lun; Lu, Cui-Tao

    2016-01-01

    Nerve growth factor (NGF) has potential in spinal cord injury (SCI) therapy, but limited by the poor physicochemical stability and low ability to cross the blood spinal cord barrier. Novel heparin-poloxamer (HP) thermo-sensitive hydrogel was constructed to enhance the NGF regeneration on SCI. NGF-HP thermo-sensitive hydrogel was prepared and related characteristics including gelation temperature, rheological behavior and micromorphology were measured. Local NGF delivery to the injured spinal cord was achieved by in situ injection in the injured space. The cellular uptake of NGF-HP hydrogel was evaluated with PC12 cells in vitro. Pathologic characteristics and neuron regeneration effects on the SCI rats were studied to evaluate the enhanced therapy of NGF-HP hydrogel. Endoplasmic reticulum (ER) stress-induced apoptosis was analyzed to explore the related mechanism in SCI regeneration. NGF-HP hydrogel showed good morphology and stable bioactivity of NGF in vitro. NGF-HP hydrogel combined treatment significantly enhanced the efficiency of NGF cellular uptake (Pregeneration. Spinal cord injury (SCI) is a devastating condition that can lead to sudden loss of sensory and autonomic function. Current treatment includes decompression surgery, injury stabilization, secondary complications prevention and rehabilitation. However, neurological recovery is limited. Nerve growth factor (NGF) has potential in SCI therapy, but limited by the poor physicochemical stability and low ability to cross the blood spinal cord barrier. Hydrogels have good affinity and compatibility to biological tissue. In this study, we developed a novel heparin-poloxamer (HP) thermo-sensitive hydrogel to enhance the spinal cord regeneration of NGF. From SCI rat experiment, HP hydrogel combined with orthotopic injection technique showed best neuroprotective effects among experimental groups. This novel combined technique will provide an effective strategy for SCI regeneration. Copyright © 2015 Acta

  19. 5-aminolevulinic acid-incorporated poly(vinyl alcohol nanofiber-coated metal stent for application in photodynamic therapy

    Directory of Open Access Journals (Sweden)

    Kang DH

    2012-05-01

    Full Text Available Jin Ju Yoo*, Chan Kim*, Chung-Wook Chung, Young-Il Jeong, Dae Hwan KangNational Research and Development Center for Hepatibiliary Disease, Pusan National University Yangsan Hospital, Gyeongnam 626-770, Korea *These authors contributed equally to this work.Background: The study investigated the use of combined photodynamic therapy (PDT and stent placement for the treatment of cholangiocarcinoma (CC. For this purpose, 5-aminolevulinic acid (ALA was incorporated into poly(vinyl alcohol (PVA nanofiber, and coated onto metal stents. Their efficacy was assessed in PDT towards HuCC-T1 CC cells.Methods: Fabrication of ALA-PVA nanofiber, and simultaneous coating onto metal stents, was performed through electrospinning. The dark-toxicity, generation of protoporphyrin IX (PpIX, and PDT effect of ALA and ALA-PVA nanofiber were studied in vitro, using HuCC-T1 CC cells.Results: The ALA-PVA nanofibers were coated onto metal stents less than 1000 nm in diameter. ALA-only displayed marginal cytotoxicity; ALA-PVA nanofiber showed less cytotoxicity. PpIX generation was not sigficantly different between ALA and ALA-PVA nanofiber treatments. PVA itself did not generate PpIX in tumor cells. ALA and ALA-PVA nanofiber displayed a similar PDT effect on tumor cells. Cell viability was decreased, dose-dependently, until ALA concentration reached 100 µg/mL. Necrosis and apoptosis of tumor cells occurred similarly for ALA and ALA- PVA nanofiber treatments.Conclusion: The ALA-PVA nanofiber-coated stent is a promising candidate for therapeutic use with cholangiocarcinoma.Keywords: nanofiber, photodynamic therapy, 5-aminolevulinic acid, poly(vinyl alcohol

  20. Thermal stability and surface acidity of mesoporous silica doubly doped by incorporation of sulfate and zirconium ions

    Energy Technology Data Exchange (ETDEWEB)

    Salas, P. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas No. 152, 07730 Mexico D.F. (Mexico)]. E-mail: psalas@imp.mx; Chen, L.F. [Departamento de Ingenieria Quimica, Universidad Autonoma Metropolitana-A, Av. San Pablo 180, Col. Reynosa-Tamaulipas, 02200 Mexico D.F. (Mexico); Wang, J.A. [Laboratorio de Catalisis y Materiales, ESIQIE, Instituto Politecnico Nacional, Col. Zacatenco, 07738 Mexico D.F. (Mexico); Armendariz, H. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas No. 152, 07730 Mexico D.F. (Mexico); Guzman, M.L. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas No. 152, 07730 Mexico D.F. (Mexico); Montoya, J.A. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas No. 152, 07730 Mexico D.F. (Mexico); Acosta, D.R. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A. P. 20-364, 01000 Mexico D.F. (Mexico)

    2005-11-15

    A sulfated Si-Zr-MCM-41 solid with highly ordered mesostructure was synthesized through a templated synthesis route where the CTAB surfactant was used as template. During the synthesis procedure, various amounts of (NH{sub 4}){sub 2}SO{sub 4} were added into the mixed solution of Zr and Si precursors to in situ sulfate the MCM-41 solids, aiming to enhance the acidity and thermal stability. The resultant materials showed a long-range ordered hexagonal arrangement with high surface area larger than 797 m{sup 2}/g and an average pore size distributed at approximate 2.5-2.8 nm. The high-resolution TEM observations confirmed that the order of the mesostructure gained when the molar ratio of SO{sub 4} {sup 2-}/(ZrO{sub 2} + SiO{sub 2}) increased from 0.1 to 0.3 but decreased as it reached 0.5, which is consistent with the results of {sup 29}Si MAS-NMR and XRD analysis. Compared to Si-MCM-41, the (Q{sup 2} + Q{sup 3})/Q{sup 4} ratio derived from the NMR spectra of the Zr-doped sample was higher, indicating that zirconium atoms were incorporated into the silica framework. Unexpectedly, in situ sulfation does not enhance the surface Broensted acidity, most likely due to the sulfur retained within the bulk of the materials; however, it indeed improved the thermal stability of the solid and long-range order of the structure.

  1. Carbon nanotubes incorporated with sol-gel derived La(OH)3 nanorods as platform to simultaneously determine ascorbic acid, dopamine, uric acid and nitrite.

    Science.gov (United States)

    Zhang, Yu; Yuan, Ruo; Chai, Yaqin; Zhong, Xia; Zhong, Huaan

    2012-12-01

    A novel material, sol-gel derived La(OH)(3) nanorods (La(OH)(3)NRs) with excellent film forming ability was prepared, and it was first designed to incorporate with carbon nanotubes (CNTs) to modify glassy carbon electrode (GCE) to simultaneously voltammetric determine ascorbic acid (AA), dopamine (DA), uric acid (UA), and nitrite (NO(2)(-)). Cyclic voltammetry (CV), transmission electron microscopy (TEM), and X-ray diffraction (XRD) were employed to characterize the sensor. Under optimal conditions, the linear response range for AA, DA, UA, and NO(2)(-) were 0.5 μmol L(-1) to 1.46 mmol L(-1), 50 nmol L(-1) to 35.36 μmol L(-1), 50 nmol L(-1) to 0.79 mmol L(-1), and 0.55 μmol L(-1) to 0.72 mmol L(-1), respectively and the detection limits were 1.67 μmol L(-1), 1.67 nmol L(-1), 1.67 nmol L(-1), and 0.18 μmol L(-1). The sensor demonstrated well stability, high selectivity and sensitivity. More importance, this material can be extended to construct other electrochemical sensors by the immobilization of enzymes and antibodies.

  2. Fabrication of phosphotungstic acid functionalized mesoporous silica composite membrane by alternative tape-casting incorporating phase inversion technique

    Science.gov (United States)

    Bai, Li; Zhang, Lan; He, Hong Quan; Rasheed, Raj Kamal S./O. Abdul; Zhang, Cai Zhi; Ding, Ovi Lian; Chan, Siew Hwa

    2014-01-01

    Meso-porous silica (MCM-41) membranes functionalized by phosphotungstic acid (HPW) for high temperature proton exchange membrane fuel cells (HT-PEMFCs) are successfully developed by a cost-effective tape-casting incorporating phase inversion and vacuum assisted wet impregnation techniques. The microstructure of the membrane is characterized by field emission scanning electron microscopy (FESEM). The effect of MCM-41 content on the tensile strength, ultimate elongation, and weight gain ratio and swelling ratio in water/methanol of the membranes are investigated in detail. The thermal stability of MCM-41 membrane with/without HPW is analyzed by thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) techniques. In particular, the effects of HPW loading and MCM-41 content on the proton conductivity of HPW/MCM-41 membranes are studied comprehensively. The results on the swelling ratio and tensile tension show that the developed membranes can be applied as an electrolyte membrane for HT-PEMFCs. The developed MCM-41 membrane, in which polyethersulfone (PESf) is used as the supporting backbone, is able to operate up to 200 °C. The single cell assembled from HPW/MCM-41 membrane with 70 wt.% HPW loading gives a peak output power of ∼230 mW cm-2 and ∼125 mW cm-2 in H2/air at 90 °C and in methanol/air at 150 °C without any humidification, respectively.

  3. The outer-coordination sphere: incorporating amino acids and peptides as ligands for homogeneous catalysts to mimic enzyme function

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Wendy J.

    2012-10-09

    Great progress has been achieved in the field of homogeneous transition metal-based catalysis, however, as a general rule these solution based catalysts are still easily outperformed, both in terms of rates and selectivity, by their analogous enzyme counterparts, including structural mimics of the active site. This observation suggests that the features of the enzyme beyond the active site, i.e. the outer-coordination sphere, are important for their exceptional function. Directly mimicking the outer-coordination sphere requires the incorporation of amino acids and peptides as ligands for homogeneous catalysts. This effort has been attempted for many homogeneous catalysts which span the manifold of catalytic reactions and often require careful thought regarding solvent type, pH and characterization to avoid unwanted side reactions or catalyst decomposition. This article reviews the current capability of synthesizing and characterizing this often difficult category of metal-based catalysts. This work was funded by the DOE Office of Science Early Career Research Program through the Office of Basic Energy Sciences. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

  4. iDNA-Prot|dis: identifying DNA-binding proteins by incorporating amino acid distance-pairs and reduced alphabet profile into the general pseudo amino acid composition.

    Directory of Open Access Journals (Sweden)

    Bin Liu

    Full Text Available Playing crucial roles in various cellular processes, such as recognition of specific nucleotide sequences, regulation of transcription, and regulation of gene expression, DNA-binding proteins are essential ingredients for both eukaryotic and prokaryotic proteomes. With the avalanche of protein sequences generated in the postgenomic age, it is a critical challenge to develop automated methods for accurate and rapidly identifying DNA-binding proteins based on their sequence information alone. Here, a novel predictor, called "iDNA-Prot|dis", was established by incorporating the amino acid distance-pair coupling information and the amino acid reduced alphabet profile into the general pseudo amino acid composition (PseAAC vector. The former can capture the characteristics of DNA-binding proteins so as to enhance its prediction quality, while the latter can reduce the dimension of PseAAC vector so as to speed up its prediction process. It was observed by the rigorous jackknife and independent dataset tests that the new predictor outperformed the existing predictors for the same purpose. As a user-friendly web-server, iDNA-Prot|dis is accessible to the public at http://bioinformatics.hitsz.edu.cn/iDNA-Prot_dis/. Moreover, for the convenience of the vast majority of experimental scientists, a step-by-step protocol guide is provided on how to use the web-server to get their desired results without the need to follow the complicated mathematic equations that are presented in this paper just for the integrity of its developing process. It is anticipated that the iDNA-Prot|dis predictor may become a useful high throughput tool for large-scale analysis of DNA-binding proteins, or at the very least, play a complementary role to the existing predictors in this regard.

  5. Analysis on antimicrobial susceptibility of bacteria on Poloxamer 407 gel%Poloxamer 407凝胶上细菌药物敏感性分析

    Institute of Scientific and Technical Information of China (English)

    宋鸿; 李林彧; 韩云竹

    2014-01-01

    目的:评价Poloxamer 407(P407)温敏性即型凝胶上细菌药物敏感性。方法采用改良Kirby-Bauer(K-B)纸片法检测9种细菌在P407和M ueller-Hinton(M H )琼脂培养基上的药物敏感性,同时比较不同抗菌药物在 P407和M H琼脂培养基上的扩散速率;采用SDS-聚丙酰胺凝胶(SDS-PAGE)电泳分析两种培养基上铜绿假单胞菌外膜蛋白的表达情况。结果 P407培养基上的抑菌圈直径普遍较M H琼脂培养基上的小;抗菌药物在这两种培养基上的扩散速率差异无统计学意义(P>0.05);铜绿假单胞菌生物膜外膜蛋白的表达与其在P407培养基上生长的表达相似,而与M H琼脂培养基上的表达不同。结论 P407作为一种培养基赋形剂,可用于临床细菌生物膜药物敏感筛选试验中。%Objective To evaluate the antimicrobial susceptibility of bacteria cultured on a Poloxamer 407(P407) thermosensi-tive in-situ gel .Methods The modified Kirby Bauer(K-B) disc diffusion method was adopted to determine the drug susceptibility of 9 kinds of bacterium isolated on the P407 and the Mueller Hinton(MH)agar culture medium, at the same time the diffusion rates of different antibacterial drugs on the P407 and the MH agar culture medium were compared;the sodium dodecylsulfate polyacrylam-ide gel electrophoresis(SDS-PAGE) was adopted to analyze the outer membrane proteins (OMPs) expression of Pseudomonas aeruginosa on these two kinds of culture medium .Results In the antimicrobial susceptibility tests, the inhibition zones on the P407 gel were found to be generally smaller than those on the MH agar.The difference in the diffusion rates of the antibacterial drugs on these two kinds of culture medium had no statistically significant difference (P> 0.05);the OMPs expression of Pseudomonas aeruginosa was similar to its growth expression on the P407 culture medium ,but different from its expression on the MH agar .Con-clusion P407 as an

  6. Hydrogen exchange during cell-free incorporation of deuterated amino acids and an approach to its inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Tonelli, Marco; Singarapu, Kiran K. [University of Wisconsin-Madison, National Magnetic Resonance Facility at Madison (NMRFAM), Department of Biochemistry (United States); Makino, Shin-ichi; Sahu, Sarata C.; Matsubara, Yuko [University of Wisconsin-Madison, Center for Eukaryotic Structural Genomics (CESG), Department of Biochemistry (United States); Endo, Yaeta [Ehime University, Cell-Free Science and Technology Research Center (Japan); Kainosho, Masatsune [Tokyo Metropolitan University, Center for Priority Areas (Japan); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, National Magnetic Resonance Facility at Madison (NMRFAM), Department of Biochemistry (United States)

    2011-12-15

    Perdeuteration, selective deuteration, and stereo array isotope labeling (SAIL) are valuable strategies for NMR studies of larger proteins and membrane proteins. To minimize scrambling of the label, it is best to use cell-free methods to prepare selectively labeled proteins. However, when proteins are prepared from deuterated amino acids by cell-free translation in H{sub 2}O, exchange reactions can lead to contamination of {sup 2}H sites by {sup 1}H from the solvent. Examination of a sample of SAIL-chlorella ubiquitin prepared by Escherichia coli cell-free synthesis revealed that exchange had occurred at several residues (mainly at Gly, Ala, Asp, Asn, Glu, and Gln). We present results from a study aimed at identifying the exchanging sites and level of exchange and at testing a strategy for minimizing {sup 1}H contamination during wheat germ cell-free translation of proteins produced from deuterated amino acids by adding known inhibitors of transaminases (1 mM aminooxyacetic acid) and glutamate synthetase (0.1 mM l-methionine sulfoximine). By using a wheat germ cell-free expression system, we produced [U-{sup 2}H, {sup 15}N]-chlorella ubiquitin without and with added inhibitors, and [U-{sup 15}N]-chlorella ubiquitin as a reference to determine the extent of deuterium incorporation. We also prepared a sample of [U-{sup 13}C, {sup 15}N]-chlorella ubiquitin, for use in assigning the sites of exchange. The added inhibitors did not reduce the protein yield and were successful in blocking hydrogen exchange at C{sup {alpha}} sites, with the exception of Gly, and at C{sup {beta}} sites of Ala. We discovered, in addition, that partial exchange occurred with or without the inhibitors at certain side-chain methyl and methylene groups: Asn-H{sup {beta}}, Asp-H{sup {beta}}, Gln-H{sup {gamma}}, Glu-H{sup {gamma}}, and Lys-H{sup {epsilon}}. The side-chain labeling pattern, in particular the mixed chiral labeling resulting from partial exchange at certain sites, should be of

  7. Structured lipids via lipase-catalyzed incorporation of eicosapentaenoic acid into borage (Borago officinalis L.) and evening primrose (Oenothera biennis L.) oils.

    Science.gov (United States)

    Senanayake, S P J Namal; Shahidi, Fereidoon

    2002-01-30

    Enzymatic acidolysis of borage oil (BO) or evening primrose oil (EPO) with eicosapentaenoic acid (20:5n-3; EPA) was studied. Of the six lipases that were tested in the initial screening, nonspecific lipase PS-30 from Pseudomonas sp. resulted in the highest incorporation of EPA into both oils. This enzyme was further studied for the influence of enzyme load, temperature, time, type of organic solvent, and mole ratio of substrates. The products from the acidolysis reaction were analyzed by gas chromatography (GC). The highest incorporation of EPA in both oils occurred at 45-55 degrees C and at 150-250 enzyme activity units. One unit of lipase activity was defined as nanomoles of fatty acids (oleic acid equivalents) produced per minute per gram of enzyme. Time course studies indicated that EPA incorporation was increased up to 26.8 and 25.2% (after 24 h) in BO and EPO, respectively. Among the solvents examined, n-hexane served best for the acidolysis of EPA with both oils. The effect of the mole ratio of oil to EPA was studied from 1:1 to 1:3. As the mole ratio of EPA increased, the incorporation increased from 25.2-26.8 to 37.4-39.9% (after 24 h). The highest EPA incorporations of 39.9 and 37.4% in BO and EPO, respectively, occurred at the stoichiometric mole ratio of 1:3 for oil to EPA.

  8. Quality of [omega]-3 fatty acid enriched low-fat chicken meat patties incorporated with selected levels of linseed flour/oil and canola flour/oil

    National Research Council Canada - National Science Library

    Ripudaman Singh; Manish K Chatli; Ashim K Biswas; Jhari Sahoo

    2014-01-01

    ...]-3 enriched fatty acids chicken meat patties (CMP) prepared with the incorporation of 4% linseed flour (T^sub 1^), 2% canola flour (T^sub 2^), 3% linseed oil (T^sub 3^), and 4% canola oil (T^sub 4...

  9. IDENTIFICATION OF THE STRUCTURE AND ORIGIN OF A THIOACIDOLYSIS MARKER COMPOUND FOR FERULIC ACID INCORPORATION INTO ANGIOSPERM LIGNINS (AND AN INDICATOR FOR CINNAMOYL-CoA REDUCTASE DEFICIENCY)

    Science.gov (United States)

    A molecular marker compound, derived from lignin by the thioacidolysis degradative method, for structures produced when ferulic acid is incorporated into lignification in angiosperms (poplar, Arabidopsis, tobacco), has been structurally identified as 1,2,2-trithioethyl ethylguaiacol [1-(4-hydroxy-3-...

  10. Profiling of Polar Lipids in Marine Oleaginous Diatom Fistulifera solaris JPCC DA0580: Prediction of the Potential Mechanism for Eicosapentaenoic Acid-Incorporation into Triacylglycerol

    Directory of Open Access Journals (Sweden)

    Yue Liang

    2014-05-01

    Full Text Available The marine oleaginous diatom Fistulifera solaris JPCC DA0580 is a candidate for biodiesel production because of its high lipid productivity. However, the substantial eicosapentaenoic acid (EPA content in this strain would affect the biodiesel quality. On the other hand, EPA is also known as the essential health supplement for humans. EPAs are mainly incorporated into glycerolipids in the microalgal cell instead of the presence as free fatty acids. Therefore, the understanding of the EPA biosynthesis including the incorporation of the EPA into glycerolipids especially triacylglycerol (TAG is fundamental for regulating EPA content for different purposes. In this study, in order to identify the biosynthesis pathway for the EPA-containing TAG species, a lipidomic characterization of the EPA-enriched polar lipids was performed by using direct infusion electrospray ionization (ESI-Q-TRAP-MS and MS/MS analyses. The determination of the fatty acid positional distribution showed that the sn-2 position of all the chloroplast lipids and part of phosphatidylcholine (PC species was occupied by C16 fatty acids. This result suggested the critical role of the chloroplast on the lipid synthesis in F. solaris. Furthermore, the exclusive presence of C18 fatty acids in PC highly indicated the biosynthesis of EPA on PC. Finally, the PC-based acyl-editing and head group exchange processes were proposed to be essential for the incorporation of EPA into TAG and chloroplast lipids.

  11. Anti-adhesive effect of poloxamer-based thermo-sensitive sol-gel in rabbit laminectomy model.

    Science.gov (United States)

    Shin, Sung Joon; Lee, Jae Hyup; So, Jungwon; Min, Kyungdan

    2016-11-01

    Poloxamer-based thermo-sensitive sol-gel has been developed to reduce the incidence of postoperative scar formation at the laminectomy site. The purpose of this study was to evaluate the anti-adhesive effect of poloxamer based thermo-sensitive sol-gel compared to hyaluronate based solution after laminectomy, using a rabbit model. A thermo-sensitive anti-adhesive with a property of sol-gel transition was manufactured by a physical mixture of Poloxamer188/407, Chitosan and Gelatin. The viscosity in different temperatures was assessed. 72 adult New Zealand rabbits underwent lumbar laminectomy and were randomly divided into experimental (treated with the newly developed agent), positive (treated with hyaluronate based solution), and negative control groups. Each group was subdivided into 1 and 4-week subgroups. Gross and histological evaluations were performed to assess the extent of epidural adhesion. The experimental group showed significantly higher viscosity compared to the positive control group and showed a significant increase of viscosity as the temperature increased. Gross evaluation showed no statistically significant differences between the 1- and 4-week subgroups. However, histologic evaluation showed significant differences both in 1- and 4-week subgroups. Although the 4-week histologic results of the experimental and the positive control subgroups showed no significant difference, both subgroups revealed higher value compared to the negative control subgroup with regard to the ratio of adhesion less than 50 %. The new poloxamer based thermo-sensitive agent showed superior efficacy over the hyaluronate based agent at 1 week postoperatively. At 4 weeks postoperatively, there were no statistically significant differences between the two agents, although both showed efficacy over the sham group.

  12. Oxygen-18 incorporation into malic acid during nocturnal carbon dioxide fixation in crassulacean acid metabolism plants: a new approach to estimating in vivo carbonic anhydrase activity

    Energy Technology Data Exchange (ETDEWEB)

    Holtum, J.A.M.; Summons, R.; Roeske, C.A.; Comins, H.N.; O' Leary, M.H.

    1984-01-01

    Crassulacean acid metabolism (CAM) plants fix carbon dioxide at night by the carboxylation of phosphoenolpyruvate. If CO2 fixation is conducted with TC YO2, then in the absence of carbonic anhydrase, the malate formed by dark CO2 fixation should also contain high levels of carbon-13 and oxygen-18. Conversely, if carbonic anhydrase is present and highly active, oxygen exchange between CO2 and cellular H2O will occur more rapidly than carboxylation, and the ( TC) malate formed will contain little or no oxygen-18 above the natural abundance level. The presence of oxygen-18 in these molecules can be detected either by nuclear magnetic resonance or by mass spectrometry. Studies of phosphoenolpyruvate carboxylase in the presence and absence of carbonic anhydrase in vitro confirm the validity of the method. When CAM plants are studied by this method, we find that most species show incorporation of a significant amount of oxygen-18. Comparison of these results with results of isotope fractionation and gas exchange studies permits calculation of the in vivo activity of carbonic anhydrase toward HCO3 compared with that of phosphoenolpyruvate carboxylase. The ratio (carbonic anhydrase activity/phosphoenolpyruvate carboxylase activity) is species dependent and varies from a low of about 7 for Ananas comosus to values near 20 for Hoya carnosa and Bryophyllum pinnatum, 40 for Kalanchoee daigremontiana, and 100 or greater for Bryophyllum tubiflorum, Kalanchoee serrata, and Kalanchoae tomentosa. Carbonic anhydrase activity increases relative to phosphoenolpyruvate carboxylase activity at higher temperature. 37 references, 2 figures, 8 tables.

  13. Effects of the Soil Incorporation of Increasing Amounts of Non-Fermented Wet Pomace on the Oil Yield and Acid Profile of Sunflower Seeds

    Directory of Open Access Journals (Sweden)

    Roberto Di Caterina

    2011-02-01

    Full Text Available The agricultural use of olive processing waste is a strategic resource in the integrated management of the agricultural system as it satisfies the two objectives of evacuating the olive-processing residue and using it beneficially for agricultural purposes. For such aims, a research was conducted in Bari (South of Italy to study the effects of the incorporation into the soil of increasing amounts of non-fermented wet pomace (WP (0, 17.5, 35, 70, 105, 140, 175, 210 Mg ha-1 on the oil yield and acid profile of sunflower seeds. The results obtained point out that the seed yield was negatively affected by the application of WP starting from 70 Mg ha-1; an opposite trend was observed for the seed oil yield. The incorporation of WP has also affected the oil fatty acids’ composition. Oleic and linoleic acids, the principal fatty acids (beyond 90% of total fatty acids, showed significant variations: from the control treatment to the one receiving the maximum application of waste, oleic acid decreased (-5.4%, linoleic acid increased (+ 6.6%, and the saturated fatty acids fraction decreased (-7.6%.

  14. Randomized controlled trial examining the effects of fish oil and multivitamin supplementation on the incorporation of n-3 and n-6 fatty acids into red blood cells.

    Science.gov (United States)

    Pipingas, Andrew; Cockerell, Robyn; Grima, Natalie; Sinclair, Andrew; Stough, Con; Scholey, Andrew; Myers, Stephen; Croft, Kevin; Sali, Avni; Pase, Matthew P

    2014-05-14

    The present randomized, placebo-controlled, double-blind, parallel-groups clinical trial examined the effects of fish oil and multivitamin supplementation on the incorporation of n-3 and n-6 fatty acids into red blood cells. Healthy adult humans (n = 160) were randomized to receive 6 g of fish oil, 6 g of fish oil plus a multivitamin, 3 g of fish oil plus a multivitamin or a placebo daily for 16 weeks. Treatment with 6 g of fish oil, with or without a daily multivitamin, led to higher eicosapentaenoic acid (EPA) composition at endpoint. Docosahexaenoic acid (DHA) composition was unchanged following treatment. The long chain LC n-3 PUFA index was only higher, compared to placebo, in the group receiving the combination of 6 g of fish oil and the multivitamin. Analysis by gender revealed that all treatments increased EPA incorporation in females while, in males, EPA was only significantly increased by the 6 g fish oil multivitamin combination. There was considerable individual variability in the red blood cell incorporation of EPA and DHA at endpoint. Gender contributed to a large proportion of this variability with females generally showing higher LC n-3 PUFA composition at endpoint. In conclusion, the incorporation of LC n-3 PUFA into red blood cells was influenced by dosage, the concurrent intake of vitamin/minerals and gender.

  15. Randomized Controlled Trial Examining the Effects of Fish Oil and Multivitamin Supplementation on the Incorporation of n-3 and n-6 Fatty Acids into Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Andrew Pipingas

    2014-05-01

    Full Text Available The present randomized, placebo-controlled, double-blind, parallel-groups clinical trial examined the effects of fish oil and multivitamin supplementation on the incorporation of n-3 and n-6 fatty acids into red blood cells. Healthy adult humans (n = 160 were randomized to receive 6 g of fish oil, 6 g of fish oil plus a multivitamin, 3 g of fish oil plus a multivitamin or a placebo daily for 16 weeks. Treatment with 6 g of fish oil, with or without a daily multivitamin, led to higher eicosapentaenoic acid (EPA composition at endpoint. Docosahexaenoic acid (DHA composition was unchanged following treatment. The long chain LC n-3 PUFA index was only higher, compared to placebo, in the group receiving the combination of 6 g of fish oil and the multivitamin. Analysis by gender revealed that all treatments increased EPA incorporation in females while, in males, EPA was only significantly increased by the 6 g fish oil multivitamin combination. There was considerable individual variability in the red blood cell incorporation of EPA and DHA at endpoint. Gender contributed to a large proportion of this variability with females generally showing higher LC n-3 PUFA composition at endpoint. In conclusion, the incorporation of LC n-3 PUFA into red blood cells was influenced by dosage, the concurrent intake of vitamin/minerals and gender.

  16. Quality of ω-3 fatty acid enriched low-fat chicken meat patties incorporated with selected levels of linseed flour/oil and canola flour/oil.

    Science.gov (United States)

    Singh, Ripudaman; Chatli, Manish K; Biswas, Ashim K; Sahoo, Jhari

    2014-02-01

    The aim of the present study was to compare the nutritional, processing and sensory characteristics of low-fat ω-3 enriched fatty acids chicken meat patties (CMP) prepared with the incorporation of 4% linseed flour (T1), 2% canola flour (T2), 3% linseed oil (T3), and 4% canola oil (T4) and to estimate their cost of production. The total fat and crude fiber content was increased (P flour. The emulsion stability and cooking yield was greater (P flours. The colour and appearance and flavour scores were lower (P flour than canola oil incorporated CMP. The texture scores were not influenced (P flour.

  17. Different kinetic in incorporation and depletion of n-3 fatty acids in erythrocytes and leukocytes of mice

    DEFF Research Database (Denmark)

    Mu, Huiling; Thogersen, Regitze Louise; Maaetoft-Udsen, Kristina

    2006-01-01

    n-3 PUFA are well known for their anti-inflammatory effects. However, there has been only limited study on the kinetics of incorporation and depletion of n-3 PUFA in immune cells. In the present study we investigated the incorporation and depletion of n-3 PUFA in erythrocytes and leukocytes in mice...... during a 6-wk feeding period. Over the first 3-wk period (the incorporation period) the mice were fed a special diet with a high n-3/n-6 PUFA ratio. In the following 3-wk period (the depletion period) the mice were fed a standard chow diet. A linear increase of the concentration of EPA and DHA...... that of depletion for n-3 PUFA. More n-3 PUFA can be incorporated into leukocytes in comparison with erythrocytes. The ratio of n-3/n-6 PUFA is more important than the amount of n-3 FA in changing the FA compositions of membrane lipids....

  18. Electrodeposited reduced graphene oxide incorporating polymerization of l-lysine on electrode surface and its application in simultaneous electrochemical determination of ascorbic acid, dopamine and uric acid.

    Science.gov (United States)

    Zhang, Dongdong; Li, Lingzhi; Ma, Weina; Chen, Xia; Zhang, Yanmin

    2017-01-01

    This paper demonstrates a novel strategy for the construction of a graphene hybrid composites film, which was fabricated by electrodeposited reduced graphene oxide (ERGO) incorporating polymerization of l-lysine (PLL) onto glassy carbon electrode (GCE). Here we show that graphene films can be prepared on electrodes directly from GO dispersions by one-step electrodeposition technique based on electropolymerized PLL as a positively charged polymer interface to adsorb negatively charged GO nanosheets through electrostatic attraction. The thickness of graphene film can be easily controlled by using the electrodeposition technique, a distinct advantage over previously developed methods. The electrochemically reduced process of GO and electropolymerization of l-lysine were investigated by cyclic voltammetry with a wide potential range. The surface morphology of the modified electrode was characterized by scanning electron microscopy. The ERGO/PLL/GCE shows conducive to electron transfer kinetics for Fe(CN)6(3-)/Fe(CN)6(4-) redox probes, compared with bare GCE, PLL/GCE and ERGO/GCE. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) at ERGO/PLL/GCE were investigated by cyclic voltammetry, and the results suggest that the modified electrode exhibits enhanced electrocatalytic activity toward these important molecules. Under physiological condition and in the co-existence system of AA, DA and UA, the ERGO/PLL/GCE showed linear voltammetric responses in the concentration of 100μM-1200μM for AA, 2.0μM-60μM for DA and 20μM-200μM for UA, and with the detection limits (S/N=3) of 2.0μM, 0.10μM and 0.15μM for AA, DA and UA, respectively. The developed method has been applied to simultaneous determination of AA, DA and UA in human urine with satisfactory recoveries of 104.2%, 95.4% and 99.9%, respectively. This work demonstrates that the attractive features of ERGO/PLL provide promising applications in simultaneous determination of AA, DA

  19. Comparative Study of Heparin-Poloxamer Hydrogel Modified bFGF and aFGF for in Vivo Wound Healing Efficiency.

    Science.gov (United States)

    Wu, Jiang; Zhu, Jingjing; He, Chaochao; Xiao, Zecong; Ye, Jingjing; Li, Yi; Chen, Anqi; Zhang, Hongyu; Li, Xiaokun; Lin, Li; Zhao, Yingzheng; Zheng, Jie; Xiao, Jian

    2016-07-27

    Wound therapy remains a clinical challenge. Incorporation of growth factors (GFs) into heparin-functionalized polymer hydrogel is considered as a promising strategy to improve wound healing efficiency. However, different GFs incorporation into the same heparin-based hydrogels often lead to different wound healing effects, and the underlying GF-induced wound healing mechanisms still remain elusive. Herein, we developed a thermos-sensitive heparin-poloxamer (HP) hydrogel to load and deliver different GFs (aFGF and bFGF) for wound healing in vivo. The resulting GFs-based hydrogels with and without HP hydrogels were systematically evaluated and compared for their wound healing efficiency by extensive in vivo tests, including wound closure rate, granulation formation, re-epithelization, cell proliferation, collagen, and angiogenesis expressions. While all GFs-based dressings with and without HP hydrogels exhibited better wound healing efficacy than controls, both HP-aFGF and HP-bFGF hydrogels demonstrated their superior healing activity to improve wound closure, granulation formation, re-epithelization, and blood vessel density by up-regulation of PCNA proliferation and collagen synthesis, as compared to GF dressings alone. More importantly, HP-aFGF dressings exhibited the higher healing efficacy than HP-bFGF dressings, indicating that different a/bFGF surface properties lead to different binding and release behaviors in HP hydrogels, both of which will affect different wound healing efficiency. On the basis of experimental observations, the working mechanisms of different healing effects of HP-GFs on full skin removal wound were proposed. This work provides different views of the design and development of an effective hydrogel-based delivery system for GFs toward rapid wound healing.

  20. Enhanced Transdermal Permeability via Constructing the Porous Structure of Poloxamer-Based Hydrogel

    Directory of Open Access Journals (Sweden)

    Wen-Yi Wang

    2016-11-01

    Full Text Available A major concern for transdermal drug delivery systems is the low bioavailability of targeted drugs primarily caused by the skin’s barrier function. The resistance to the carrier matrix for the diffusion and transport of drugs, however, is routinely ignored. This study reports a promising and attractive approach to reducing the resistance to drug transport in the carrier matrix, to enhance drug permeability and bioavailability via enhanced concentration-gradient of the driving force for transdermal purposes. This approach simply optimizes and reconstructs the porous channel structure of the carrier matrix, namely, poloxamer 407 (P407-based hydrogel matrix blended with carboxymethyl cellulose sodium (CMCs. Addition of CMCs was found to distinctly improve the porous structure of the P407 matrix. The pore size approximated to normal distribution as CMCs were added and the fraction of pore number was increased by over tenfold. Transdermal studies showed that P407/CMCs saw a significant increase in drug permeability across the skin. This suggests that P407/CMC with improved porous structure exhibits a feasible and promising way for the development of transdermal therapy with high permeability and bioavailability, thereby avoiding or reducing use of any chemical enhancers.

  1. Poloxamer-hydroxyethyl cellulose-α-cyclodextrin supramolecular gels for sustained release of griseofulvin.

    Science.gov (United States)

    Marcos, Xelhua; Pérez-Casas, Silvia; Llovo, José; Concheiro, Angel; Alvarez-Lorenzo, Carmen

    2016-03-16

    Supramolecular gels of poloxamer-hydroxyethyl cellulose (HEC)-α-cyclodextrin (αCD) were developed aiming to obtain synergisms regarding solubilization and sustained release of griseofulvin for topical application. The effects of αCD concentration (0-10%w/w) on the phase behavior of aqueous dispersions of Pluronic(®) P123 (14%w/w) mixed with HEC (2%w/w) were evaluated at 4, 20 and 37°C. The cooperative effects of the inclusion complex formation between poly(ethylene oxide) (PEO) blocks and HEC with αCD prevented phase separation and led to supramolecular networks that solubilize the antifungal drug. Rheological and bioadhesive properties of gels with and without griseofulvin could be easily tuned modulating the polymers proportions. Supramolecular gels underwent sol-gel transition at lower temperature than P123 solely dispersions and enabled drug sustained release for at least three weeks. All gels demonstrated good biocompatibility in the HET-CAM test. Furthermore, the drug-loaded gels showed activity against Trichophyton rubrum and Trichophyton mentagrophytes and thus may be useful for the treatment of tinea capitis and other cutaneous fungal infections.

  2. Membrane Sealant Poloxamer P188 Protects Against Isoproterenol Induced Cardiomyopathy in Dystrophin Deficient Mice

    Directory of Open Access Journals (Sweden)

    Sali Arpana

    2011-05-01

    Full Text Available Abstract Background Cardiomyopathy in Duchenne muscular dystrophy (DMD is an increasing cause of death in patients. The absence of dystrophin leads to loss of membrane integrity, cell death and fibrosis in cardiac muscle. Treatment of cardiomyocyte membrane instability could help prevent cardiomyopathy. Methods Three month old female mdx mice were exposed to the β1 receptor agonist isoproterenol subcutaneously and treated with the non-ionic tri-block copolymer Poloxamer P188 (P188 (460 mg/kg/dose i.p. daily. Cardiac function was assessed using high frequency echocardiography. Tissue was evaluated with Evans Blue Dye (EBD and picrosirius red staining. Results BL10 control mice tolerated 30 mg/kg/day of isoproterenol for 4 weeks while death occurred in mdx mice at 30, 15, 10, 5 and 1 mg/kg/day within 24 hours. Mdx mice tolerated a low dose of 0.5 mg/kg/day. Isoproterenol exposed mdx mice showed significantly increased heart rates (p Conclusions This model suggests that chronic intermittent intraperitoneal P188 treatment can prevent isoproterenol induced cardiomyopathy in dystrophin deficient mdx mice.

  3. Position-specific incorporation of fluorescent non-natural amino acids into maltose-binding protein for detection of ligand binding by FRET and fluorescence quenching.

    Science.gov (United States)

    Iijima, Issei; Hohsaka, Takahiro

    2009-04-17

    Position-specific incorporation of fluorescent groups is a useful method for analysis of the functions and structures of proteins. We have developed a method for the incorporation of visible-wavelength-fluorescent non-natural amino acids into proteins in a cell-free translation system. Using this technique, we introduced one or two BODIPY-linked amino acids into maltose-binding protein (MBP) to obtain MBP derivatives showing ligand-dependent changes in fluorescence intensity or intensity ratio. BODIPY-FL-aminophenylalanine was incorporated in place of 15 tyrosines, as well as the N-terminal Lys1, and the C-terminal Lys370 of MBP. Fluorescence measurements revealed that MBP containing a BODIPY-FL moiety in place of Tyr210 showed a 13-fold increase in fluorescence upon binding of maltose. Tryptophan-to-phenylalanine substitutions suggest that the increase in fluorescence was the result of a decrease in the quenching of BODIPY-FL by tryptophan located around the binding site. MBP containing a BODIPY-558 moiety also showed a maltose-dependent increase in fluorescence. BODIPY-FL was then additionally incorporated in place of Lys1 of the BODIPY-558-containing MBP as a response to the amber codon. Fluorescence measurements with excitation of BODIPY-FL showed a large change in fluorescence intensity ratio (0.13 to 1.25) upon binding of maltose; this change can be attributed to fluorescence resonance energy transfer (FRET) and maltose-dependent quenching of BODIPY-558. These results demonstrate the usefulness of the position-specific incorporation of fluorescent amino acids in the fluorescence-based detection of protein functions.

  4. A randomized study of the effect of fish oil on n-3 fatty acid incorporation and nutritional status in lung cancer patients

    DEFF Research Database (Denmark)

    Andersen, Jens Rikardt; Dannerfjord, Stina Hjerrild; Nørgaard, Michael

    2015-01-01

    Long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFA) have been proposed to have beneficial effect on cancer cachexia. The aims of the present study were to a) determine the incorporation of n-3 LCPUFA in erythrocytes (RBC) as a measurement of compliance to fish oil (FO)-supplement in lung canc...... in the ROg roup. Neither intention-to-treat analysis nor per-protocol-analysis revealed any statistically significant differences between the groups with respect to clinical outcomes....

  5. Quality of ω-3 fatty acid enriched low-fat chicken meat patties incorporated with selected levels of linseed flour/oil and canola flour/oil

    OpenAIRE

    Singh, Ripudaman; Chatli, Manish K.; Biswas, Ashim K.; Sahoo, Jhari

    2011-01-01

    The aim of the present study was to compare the nutritional, processing and sensory characteristics of low-fat ω-3 enriched fatty acids chicken meat patties (CMP) prepared with the incorporation of 4% linseed flour (T1), 2% canola flour (T2), 3% linseed oil (T3), and 4% canola oil (T4) and to estimate their cost of production. The total fat and crude fiber content was increased (P 

  6. Preparation and luminescence properties of europium complex with a-naphthylacetic acid incorporated in silica matrix by sol-gel method

    Institute of Scientific and Technical Information of China (English)

    陈野; 蔡伟民; 孙晓君; 崔丹; 于英宁

    2004-01-01

    Europium ternary complex of Eu (NNA)3(NNA=o-naphthylacetic acid) was embedded in silica matrix at different ratios by sol-gel method. The luminescence properties of silica composites were studied by comparing them with those of corresponding pure complex by means of excitation, emission spectra and lifetimes. The fluorescence lifetime was prolonged when the pure complex was incorporated in silica matrix. The relative fluorescence intensity and fluorescence lifetimes increased simultaneously with the increase of Eu(NNA)3.

  7. Biochemistry of Suberization: Incorporation of [1-C]Oleic Acid and [1-C]Acetate into the Aliphatic Components of Suberin in Potato Tuber Disks (Solanum tuberosum).

    Science.gov (United States)

    Dean, B B; Kolattukudy, P E

    1977-01-01

    Biosynthesis of the aliphatic components of suberin was studied in suberizing potato (Solanum tuberosum) slices with [1-(14)C]oleic acid and [1-(14)C]acetate as precursors. In 4-day aged tissue, [1-(14)C]oleic acid was incorporated into an insoluble residue, which, upon hydrogenolysis (LiA1H(4)), released the label into chloroform-soluble products. Radio thin layer and gas chromatographic analyses of these products showed that (14)C was contained exclusively in octadecenol and octadecene-1, 18-diol. OsO(4) treatment and periodate cleavage of the resulting tetraol showed that the labeled diol was octadec-9-ene-1, 18-diol, the product expected from the two major components of suberin, namely 18-hydroxyoleic acid and the corresponding dicarboxylic acid. Aged potato slices also incorporated [1-(14)C]acetate into an insoluble material. Hydrogenolysis followed by radio chromatographic analyses of the products showed that (14)C was contained in alkanols and alkane-alpha,omega-diols. In the former fraction, a substantial proportion of the label was contained in aliphatic chains longer than C(20), which are known to be common constituents of suberin. In the labeled diol fraction, the major component was octadec-9-ene-1,18-diol, with smaller quantities of saturated C(16), C(18), C(20), C(22), and C(24)-alpha,omega-diols. Soluble lipids derived from [1-(14)C]acetate in the aged tissue also contained labeled very long acids from C(20) to C(28), as well as C(22) and C(24) alcohols, but no labeled omega-hydroxy acids or dicarboxylic acids were detected. Label was also found in n-alkanes isolated from the soluble lipids, and the distribution of label among them was consistent with the composition of n-alkanes found in the wound periderm of this tissue; C(21) and C(23) were the major components with lesser amounts of C(19) and C(25). The amount of (14)C incorporated into these bifunctional monomers in 0-, 2-, 4-, 6-, and 8-day aged tissue were 0, 1.5, 2.5, 0.8, and 0.3% of the

  8. Comparison of Isotope-labeled Amino Acid Incorporation Rates (CILAIR) Provides a Quantitative Method to Study Tissue Secretomes

    NARCIS (Netherlands)

    Roelofsen, Johan; Dijkstra, Martijn; Weening, Desiree; de Vries, Marcel; Hoek, Annemieke; Vonk, Roel J.

    2009-01-01

    Adipose tissue is an endocrine organ involved in regulation of whole-body energy metabolism via storage of lipids and secretion of various peptide hormones (adipokines). We previously characterized the adipose tissue secretome and showed that [(13)C]lysine incorporation into secreted proteins can be

  9. Comparison of Isotope-labeled Amino Acid Incorporation Rates (CILAIR) Provides a Quantitative Method to Study Tissue Secretomes

    NARCIS (Netherlands)

    Roelofsen, Johan; Dijkstra, Martijn; Weening, Desiree; de Vries, Marcel; Hoek, Annemieke; Vonk, Roel J.

    2009-01-01

    Adipose tissue is an endocrine organ involved in regulation of whole-body energy metabolism via storage of lipids and secretion of various peptide hormones (adipokines). We previously characterized the adipose tissue secretome and showed that [(13)C]lysine incorporation into secreted proteins can be

  10. Comparison of Isotope-labeled Amino Acid Incorporation Rates (CILAIR) Provides a Quantitative Method to Study Tissue Secretomes

    NARCIS (Netherlands)

    Roelofsen, Johan; Dijkstra, Martijn; Weening, Desiree; de Vries, Marcel; Hoek, Annemieke; Vonk, Roel J.

    Adipose tissue is an endocrine organ involved in regulation of whole-body energy metabolism via storage of lipids and secretion of various peptide hormones (adipokines). We previously characterized the adipose tissue secretome and showed that [(13)C]lysine incorporation into secreted proteins can be

  11. Chloroindolyl-3-acetic Acid and its Methyl Ester Incorporation of 36Cl in Immature Seeds of Pea and Barley

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1974-01-01

    compounds besides Cl−. One compound, present in pea and probably in barley, cochromatographed with a mixture of 4- and 6-chloroindolyl-3-acetic acid methyl esters. Another, detected in pea, but probably not in barley, cochromatographed with a mixture of 4-and 6-chloroindolyl-3-acetic acids....

  12. Incorporation of dietary n-3 fatty acids into selective phosphatidylcholine lipids in human plasma after salmon intake

    Science.gov (United States)

    Elevated intake of n-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) is associated with reduced risk for cardiovascular disease. Intake of n-3 LCPUFA is often quantified by analysis of plasma phospholipid fatty acids (PLFA); however, the typical analysis by gas chromatography does not allow fo...

  13. Four-base codon-mediated incorporation of non-natural amino acids into proteins in a eukaryotic cell-free translation system.

    Science.gov (United States)

    Taira, Hikaru; Fukushima, Masaharu; Hohsaka, Takahiro; Sisido, Masahiko

    2005-05-01

    Various four-base codons have been shown to work for the introduction of non-natural amino acids into proteins in an Escherichia coli cell-free translation system. Here, a four-base codon-mediated non-natural mutagenesis was applied to a eukaryotic rabbit reticulocyte cell-free translation system. Mutated streptavidin mRNAs containing four-base codons were prepared and added to a rabbit reticulocyte lysate in the presence of tRNAs that were aminoacylated with a non-natural amino acid and had the corresponding four-base anticodons. A Western blot analysis of translation products indicated that the four-base codons CGGU, CGCU, CCCU, CUCU, CUAU, and GGGU were efficiently decoded by the aminoacyl-tRNAs having the corresponding four-base anticodons. In contrast, the four-base codons AGGU, AGAU, CGAU, UUGU, UCGU, and ACGU were not decoded. The stop codon-derived four-base codons UAGU, UAAU, and UGAU were found to be inefficient, whereas the amber codon UAG and opal codon UGA were efficient for the incorporation of non-natural amino acids. The application of the expanded genetic code in a eukaryotic cell-free system opens the possibility of a four-base codon-mediated incorporation of non-natural amino acids into proteins in living eukaryotic cells.

  14. The chain length of lignan macromolecule from flaxseed hulls is determined by the incorporation of coumaric acid glucosides and ferulic acid glucosides

    NARCIS (Netherlands)

    Struijs, K.; Vincken, J.P.; Doeswijk, T.G.; Voragen, A.G.J.; Gruppen, H.

    2009-01-01

    Lignan macromolecule from flaxseed hulls is composed of secoisolariciresinol diglucoside (SDG) and herbacetin diglucoside (HDG) moieties ester-linked by 3-hydroxy-3-methylglutaric acid (HMGA), and of p-coumaric acid glucoside (CouAG) and ferulic acid glucoside (FeAG) moieties ester-linked directly t

  15. Cellular Composition of the Spleen and Changes in Splenic Lysosomes in the Dynamics of Dyslipidemia in Mice Caused by Repeated Administration of Poloxamer 407.

    Science.gov (United States)

    Goncharova, N V; Shurlygina, A V; Mel'nikova, E V; Karmatskikh, O L; Avrorov, P A; Loktev, K V; Korolenko, T A

    2015-11-01

    We studied the effect of dyslipidemia induced by poloxamer 407 (300 mg/kg twice a week for 30 days) on cellular composition of the spleen and splenocyte lysosomes in mice. Changes in blood lipid profile included elevated concentrations of total cholesterol, aterogenic LDL, and triglycerides most pronounced in 24 h after the last poloxamer 407 injection; gradual normalization of lipid profile was observed in 4 days (except triglycerides) and 10 days. The most pronounced changes in the spleen (increase in organ weight and number of cells, inhibition in apoptosis, and reduced accumulation of vital dye acridine orange in lysosomes) were detected on day 4; on day 10, the indices returned to normal. Cathepsin D activity in the spleen also increased at these terms. The relationship between changes in the cellular composition of the spleen and dynamics of serum lipid profile in mice in dyslipidemia caused by repeated administrations of relatively low doses of poloxamer 407 is discussed.

  16. Synthesis and conformational analysis of hybrid α/β-dipeptides incorporating S-glycosyl-β(2,2)-amino acids.

    Science.gov (United States)

    García-González, Iván; Mata, Lara; Corzana, Francisco; Jiménez-Osés, Gonzalo; Avenoza, Alberto; Busto, Jesús H; Peregrina, Jesús M

    2015-01-12

    We synthesized and carried out the conformational analysis of several hybrid dipeptides consisting of an α-amino acid attached to a quaternary glyco-β-amino acid. In particular, we combined a S-glycosylated β(2,2)-amino acid and two different types of α-amino acid, namely, aliphatic (alanine) and aromatic (phenylalanine and tryptophan) in the sequence of hybrid α/β-dipeptides. The key step in the synthesis involved the ring-opening reaction of a chiral cyclic sulfamidate, inserted in the peptidic sequence, with a sulfur-containing nucleophile by using 1-thio-β-D-glucopyranose derivatives. This reaction of glycosylation occurred with inversion of configuration at the quaternary center. The conformational behavior in aqueous solution of the peptide backbone and the glycosidic linkage for all synthesized hybrid glycopeptides was analyzed by using a protocol that combined NMR experiments and molecular dynamics with time-averaged restraints (MD-tar). Interestingly, the presence of the sulfur heteroatom at the quaternary center of the β-amino acid induced θ torsional angles close to 180° (anti). Notably, this value changed to 60° (gauche) when the peptidic sequence displayed aromatic α-amino acids due to the presence of CH-π interactions between the phenyl or indole ring and the methyl groups of the β-amino acid unit.

  17. Tuning the degradation rate of calcium phosphate cements by incorporating mixtures of polylactic-co-glycolic acid microspheres and glucono-delta-lactone microparticles.

    Science.gov (United States)

    Sariibrahimoglu, Kemal; An, Jie; van Oirschot, Bart A J A; Nijhuis, Arnold W G; Eman, Rhandy M; Alblas, Jacqueline; Wolke, Joop G C; van den Beucken, Jeroen J J P; Leeuwenburgh, Sander C G; Jansen, John A

    2014-11-01

    Calcium phosphate cements (CPCs) are frequently used as synthetic bone graft materials in view of their excellent osteocompatibility and clinical handling behavior. Hydroxyapatite-forming CPCs, however, degrade at very low rates, thereby limiting complete bone regeneration. The current study has investigated whether degradation of apatite-forming cements can be tuned by incorporating acid-producing slow-resorbing poly(D,L-lactic-co-glycolic) acid (PLGA) porogens, fast-resorbing glucono-delta-lactone (GDL) porogens, or mixtures thereof. The physicochemical, mechanical, and degradation characteristics of these CPC formulations were systematically analyzed upon soaking in phosphate-buffered saline (PBS). In parallel, various CPC formulations were implanted intramuscularly and orthotopically on top of the transverse process of goats followed by analysis of the soft tissue response and bone ingrowth after 12 weeks. In vitro degradation of GDL was almost completed after 2 weeks, as evidenced by characterization of the release of gluconic acid, while PLGA-containing CPCs released glycolic acid throughout the entire study (12 weeks), resulting in a decrease in compression strength of CPC. Extensive in vitro degradation of the CPC matrix was observed upon simultaneous incorporation of 30% PLGA-10% GDL. Histomorphometrical evaluation of the intramuscularly implanted samples revealed that all CPCs exhibited degradation, accompanied by an increase in capsule thickness. In the in vivo goat transverse process model, incorporation of 43% PLGA, 30% PLGA-5% GDL, and 30% PLGA-10% GDL in CPC significantly increased bone formation and resulted in higher bone height compared with both 10% GDL and 20% GDL-containing CPC samples.

  18. Improving thermal stability and light fastness of Acid Red 114 by incorporating its anions in a ZnAl-layered double hydroxides matrix

    Institute of Scientific and Technical Information of China (English)

    Haifeng Zhu; Liren Wang; Pinggui Tang; Yongjun Feng; Dianqing Li

    2012-01-01

    Incorporation of anions of Acid Red 114 dye (1,3-naphthalenedisulfonic acid,8-[2-[3,3'-dimethyl-4'-[2-[4-[[(4-methylphenyl)sulfonyl]oxy] phenyl]diazenyl] [1,1'-biphenyl]-4-yl]diazenyl]-7-hydroxy-,disodium salt) (denoted as NPDA) into ZnAl-layered double hydroxides (LDHs) has been carried out by an anionexchange method in an effort to improve their thermal stability and light fastness.After intercalation of NPDA anions,the interlayer distance of the LDHs increases from 0.87 to 2.18nm,confirming their incorporation into the interlayer galleries of the LDHs host.Infrared spectroscopy and thermogravimetric analysis revealed the presence of host-guest interactions between LDHs layers and NPDA anions.The thermal stability of NPDA and ZnAl-NPDA-LDHs was compared by thermogravimetric-differential thermal analysis,UV-visible spectroscopy and infrared spectroscopy.It was found that the thermal stability of NPDA anions was markedly improved by incorporation into the ZnAl-LDHs matrix,while the light fastness was also enhanced.

  19. Exploring the incorporation of nitrogen in titanium and its influence on the electrochemical corrosion resistance in acidic media

    Science.gov (United States)

    Velasco-Velez, J. J.; Davaasuren, B.; Scherzer, M.; Cap, S.; Willinger, M.; Guo, J.-H.; Schlögl, R.; Knop-Gericke, A.

    2016-08-01

    The role of the nitrogen incorporation into titanium, its chemical nature, the location in the titanium lattice and its electrochemical performance were investigated by a combination of several spectroscopy and microscopy techniques using samples prepared by CVD of NH3 at different temperatures and successive electrochemically tested in 1 M of HClO4. We found that nitrogen is incorporated in either the interstitial or substitutional site of the lattice depending on the preparation temperature modifying strongly its corrosion resistance which was ascribed to the N 2p hybridization with the Ti 3d orbitals. It was found that at low temperature the N 2p orbitals were more likely to hybridize with Ti3d-t2g orbitals while higher temperature favors the hybridization with the Ti3d-eg orbitals. This is responsible for the corrosion resistance shown by the samples prepared at higher temperature.

  20. Stable isotope labeling, in vivo, of D- and L-tryptophan pools in lemna gibba and the low incorporation of label into indole-3-acetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Baldi, B.G. (Dept. of Agriculture, Beltsville, MD (USA)); Maher, B.R. (Univ. of Maryland, College Park (USA)); Slovin, J.P.; Cohen, J.D. (Dept. of Agriculture, Beltsville, MD (USA) Univ. of Maryland, College Park (USA))

    1991-04-01

    The authors present evidence that the role of tryptophan and other potential intermediates in the pathways that could lead to indole derivatives needs to be reexamined. Two lines of Lemna gibba were tested for uptake of ({sup 15}N-indole)-labeled tryptophan isomers and incorporation of that label into free indole-3-acetic acid (IAA). Both lines required levels of L-({sup 15}N)tryptophan 2 to 3 orders of magnitude over endogenous levels in order to obtain measurable incorporation of label into IAA. Labeled L-tryptophan was extractable from plant tissue after feeding and showed no measurable isomerization into D-tryptophan. D-({sup 15}N)trytophan supplied to Lemna at rates of approximately 400 times excess of endogenous D-tryptophan levels (to yield an isotopic enrichment equal to that which allowed detection of the incorporation of L-tryptophan into IAA), did not result in measurable incorporation of label into free IAA. These results demonstrate that L-tryptophan is a more direct precursor to IAA than the D isomer and suggest (a) that the availability of tryptophan in vivo is not a limiting factor in the biosynthesis of IAA, thus implying that other regulatory mechanisms are in operation and (b) that L-tryptophan also may not be a primary precursor to IAA in plants.

  1. Antimicrobial evaluation of novel poly-lactic acid based nanocomposites incorporated with bioactive compounds in-vitro and in refrigerated vacuum-packed cooked sausages.

    Science.gov (United States)

    Rezaeigolestani, Mohammadreza; Misaghi, Ali; Khanjari, Ali; Basti, Afshin Akhondzadeh; Abdulkhani, Ali; Fayazfar, Samira

    2017-11-02

    Biodegradability and antimicrobial activity of food packaging materials are among the most attractive parameters in modern food industries. In order to develop biodegradable poly-lactic acid (PLA) film to antibacterial nanocomposites, different concentration of Zataria multiflora Bioss. essential oil (ZME), propolis ethanolic extract (PEE) and cellulose nanofiber (CNF) were incorporated to the polymer by solvent casting method. The resulting films were characterized by mechanical and physical tests and their antimicrobial application was evaluated in-vitro against four common foodborne pathogens and in vacuum-packed cooked sausages during refrigerated storage. Mechanical examination revealed that addition of ZME and PEE made films more flexible and incorporation of CNF improved almost all mechanical parameters tested. Moreover, according to physical analysis, incorporation of 0.5% v/v ZME to the composite primary solutions improved water vapor permeability of the resulting films. Almost all of the active films were effective against the tested bacteria except for PLA/PEE films, and maximum antibacterial effects recorded for the films containing both ZME and PEE. Based on the microbiological and sensory evaluation of the sausages, all of the PLA/1%ZME/PEE composites increased the shelf life to >40days. The results indicate that incorporation of natural antimicrobial substances such as ZME and PEE to packaging material could be an interesting approach in development of active packaging material without significant negative effect on polymer technical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Inter-tissue differences in fatty acid incorporation as a result of dietary oil manipulation in Port Jackson sharks (Heterodontus portusjacksoni).

    Science.gov (United States)

    Beckmann, Crystal L; Mitchell, James G; Stone, David A J; Huveneers, Charlie

    2014-06-01

    Fatty acid profile analysis is a tool for dietary investigation that may complement traditional stomach contents analysis. While recent studies have shown that the liver of sharks fed different diets have differing fatty acid profiles, the degree to which diet is reflected in shark blood serum and muscle tissue is still poorly understood. An 18-week controlled feeding experiment was undertaken using captive Port Jackson sharks (Heterodontus portusjacksoni). Sharks were fed exclusive diets of artificial pellets treated with fish or poultry oil and sampled every 6 weeks. The fatty acid profiles from liver, blood serum, and muscle were affected differently, with the period from which significant differences were observed varying by tissue and diet type. The total fatty acid profiles of fish oil and poultry oil fed sharks were significantly different from week 12 onwards in the liver and blood serum, but significant differences were only observed by week 18 in the muscle tissue of sharks fed different diets. The drivers of dissimilarity which aligned with dietary input were 14:0, 18:2n-6, 20:5n-3, 18:1n-9 and 22:6n-3 in the liver and blood serum. Dietary fatty acids accumulated more consistently in the liver than in the blood plasma or muscle, likely due to its role as the central organ for fat processing and storage. Blood serum and muscle fatty acid profiles were influenced by diet, but fluctuated over-time. The low level of correlation between diet and muscle FA profiles is likely a result of low levels of fat (shark muscle tissues. Our findings describe inter-tissue differences in the incorporation of fatty acids from the diet to consumer, which should be taken into account when interpreting dietary patterns from fatty acid profiles.

  3. Preparation, characterization and application in deep catalytic ODS of the mesoporous silica pillared clay incorporated with phosphotungstic acid.

    Science.gov (United States)

    Li, Baoshan; Liu, Zhenxing; Liu, Jianjun; Zhou, Zhiyuan; Gao, Xiaohui; Pang, Xinmei; Sheng, Huiting

    2011-10-15

    Mesoporous silica pillared clay (SPC) materials with different contents of H(3)PW(12)O(40) (HPW) heteropoly acid were synthesized by introducing HPW into clay interlayer template in an acidic suspension using sol-gel method. Samples with similar HPW loadings were also prepared by impregnation method using SPC as the support. The results of the characterizations showed that HPW was dispersed more homogeneously in the encapsulated samples than in the impregnated samples. The encapsulated materials exhibited better catalytic performance than the impregnated samples in oxidative desulfurization of dibenzothiophene-containing model oil. The sulfur removal reached up to 98.6% for the model oil under the experiential conditions.

  4. A randomized study of the effect of fish oil on n-3 fatty acid incorporation and nutritional status in lung cancer patients

    DEFF Research Database (Denmark)

    Andersen, Jens Rikardt; Dannerfjord, Stina Hjerrild; Nørgaard, Michael;

    2015-01-01

    either 20 ml of FO or 20 ml of rapeseed oil (RO) daily. Patients were evaluated every three weeks. Twenty-five patients participated in the study for more than 21 days. The RBC content in FO-group increased with 35%, 137% and 44%, respectively (p ...Long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFA) have been proposed to have beneficial effect on cancer cachexia. The aims of the present study were to a) determine the incorporation of n-3 LCPUFA in erythrocytes (RBC) as a measurement of compliance to fish oil (FO)-supplement in lung cancer...

  5. Stabilization of Parallel Triplexes by Twisted Intercalating Nucleic Acids (TINAs) Incorporating 1,2,3-Triazole Units and Prepared by Microwave-Accelerated Click Chemistry

    DEFF Research Database (Denmark)

    Géci, Imrich; Filitchev, Vyacheslav Viatcheslav; Pedersen, Erik Bjerreg.

    2007-01-01

    A highly efficient method for postsynthetic modification of unprotected oligonucleotides incorporating internal insertions of (R)-1-O-(4-ethynylbenzyl)glycerol has been developed through the application of click chemistry with water-insoluble pyren-1-yl azide and water-soluble benzyl azide...... and acceleration by microwave irradiation. The twisted intercalating nucleic acids (TINAs) obtained in these reactions, possessing bulged insertions of (R)-3-O-{4-[1-(pyren-1-yl)-1H-1,2,3-triazol-4-yl]benzyl}glycerol (7), formed parallel triplexes with thermal stabilities of 20.0, 34.0, and 40.0 °C at pH 7...

  6. Fabrication of electrospun polylactic acid nanofilm incorporating cinnamon essential oil/β-cyclodextrin inclusion complex for antimicrobial packaging.

    Science.gov (United States)

    Wen, Peng; Zhu, Ding-He; Feng, Kun; Liu, Fang-Jun; Lou, Wen-Yong; Li, Ning; Zong, Min-Hua; Wu, Hong

    2016-04-01

    A novel antimicrobial packaging material was obtained by incorporating cinnamon essential oil/β-cyclodextrin inclusion complex (CEO/β-CD-IC) into polylacticacid (PLA) nanofibers via electrospinning technique. The CEO/β-CD-IC was prepared by the co-precipitation method and SEM and FT-IR spectroscopy analysis indicated the successful formation of CEO/β-CD-IC, which improved the thermal stability of CEO. The CEO/β-CD-IC was then incorporated into PLA nanofibers by electrospinning and the resulting PLA/CEO/β-CD nanofilm showed better antimicrobial activity compared to PLA/CEO nanofilm. The minimum inhibitory concentration (MIC) of PLA/CEO/β-CD nanofilm against Escherichia coli and Staphylococcus aureus was approximately 1 mg/ml (corresponding CEO concentration 11.35 μg/ml) and minimum bactericidal concentration (MBC) was approximately 7 mg/ml (corresponding CEO concentration 79.45 μg/ml). Furthermore, compared with the casting method, the mild electrospinning process was more favorable for maintaining greater CEO in the obtained film. The PLA/CEO/β-CD nanofilm can effectively prolong the shelf life of pork, suggesting it has potential application in active food packaging.

  7. Guarana (Paullinia cupana) ameliorates memory impairment and modulates acetylcholinesterase activity in Poloxamer-407-induced hyperlipidemia in rat brain.

    Science.gov (United States)

    Ruchel, Jader B; Braun, Josiane B S; Adefegha, Stephen A; Guedes Manzoni, Alessandra; Abdalla, Fátima H; de Oliveira, Juliana S; Trelles, Kelly; Signor, Cristiane; Lopes, Sônia T A; da Silva, Cássia B; Castilhos, Lívia G; Rubin, Maribel A; Leal, Daniela B R

    2017-01-01

    Hyperlipidemia is a risk factor for the development of cognitive dysfunction and atherosclerosis. Natural compounds have recently received special attention in relation to the treatment of disease due to their low cost and wide margin of safety. Thus, the aim of this study was to determine the possible preventive effect of guarana powder (Paullinia cupana) on memory impairment and acetylcholinesterase (AChE) activity in the brain structures of rats with Poloxamer-407-induced hyperlipidemia. Adult male Wistar rats were pretreated with guarana (12.5, 25 and 50mg/kg/day) and caffeine (0.2mg/kg/day) by gavage for a period of 30days. Simvastatin (0.04mg/kg) was administered as a comparative standard. Acute hyperlipidemia was induced with intraperitoneal injections of 500mg/kg of Poloxamer-407. Memory tests and evaluations of anxiety were performed. The cortex, cerebellum, hippocampus, hypothalamus and striatum were separated to assess acetylcholinesterase activity. Our results revealed that guarana powder was able to reduce the levels of TC and LDL-C in a manner similar to simvastatin. Guarana powder also partially reduced the liver damage caused by hyperlipidemia. Guarana was able to prevent changes in the activity of AChE and improve memory impairment due to hyperlipidemia. Guarana powder may therefore be a source of promising phytochemicals that can be used as adjuvant therapy in the management of hyperlipidemia and cognitive disorders.

  8. IR 820 dye encapsulated in polycaprolactone glycol chitosan: Poloxamer blend nanoparticles for photo immunotherapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Piyush; Srivastava, Rohit, E-mail: rsrivasta@iitb.ac.in

    2015-12-01

    In the present study, we have fabricated biocompatible and biodegradable monodisperse IR 820 encapsulated polycaprolactone (PCL) glycol chitosan (GC): Poloxamer blend nanoparticles (PP-IR NPs) for imaging and effective photo-immunotherapy. IR 820 has been used as an imaging and photothermal agent whereas glycol chitosan (GC) as an immunostimulatory agent. The combination of IR 820, poloxamer, and GC can be used effectively for photoimmunotherapy for cancer, drug-resistant and TNF-α resistant estrogen positive breast cancer. PP-IR NPs are stable in aqueous solution. The uniform size of 100–220 nm with a high zeta value of + 38 ± 2 mV led them to accumulate in cancer cells. Laser treatment did not affect the morphology of PP-IR NPs as observed under the transmission electron microscope (TEM). In vitro cytotoxicity studies on MCF-7 cells showed enhanced toxicity upon laser treatment. Further, we validated the cell death by reactive oxygen species (ROS) production. Our studies thus showed that PP-IR NPs are effective in suppressing metastatic cancer as the combinational therapy leads to the formation of apoptotic bodies in MCF-7 cells. - Highlights: • PPIR nanoparticles for photoimmunotherapy for cancer • IR 820/GC serves as theranostic and immunostimulatory. • Photoimmunotherapy enhances cytotoxicity by reactive oxygen species production.

  9. Rheological characterization and in vivo evaluation of thermosensitive poloxamer-based hydrogel for intramuscular injection of piroxicam.

    Science.gov (United States)

    Xuan, Jing-Ji; Balakrishnan, Prabagar; Oh, Dong Hoon; Yeo, Woo Hyun; Park, San Man; Yong, Chul Soon; Choi, Han-Gon

    2010-08-16

    To develop an industrially practical thermosensitive injectable hydrogel that is easy to administer, gels quickly in the body and allows sustained release of the drug, poloxamer-based hydrogels containing piroxicam as a model drug were prepared with poloxamer, sodium hydroxide and sodium chloride using the cold method. Their rheological characterization, dissolution and pharmacokinetics after intramuscular administration to rabbits were evaluated. Among the ingredients tested, sodium hydroxide and piroxicam decreased the viscosity and retarded the gelation time of the injectable gel. However, sodium chloride did the opposite. The thermosensitive injectable gel composed of 2.5% piroxicam, 15% P 407, 17% P 188, 0.01% sodium hydroxide and 1.6% sodium chloride was instantly applied to practical industrial product, since it was easy to administer intramuscularly and gelled quickly in the body. The drug was dissolved out of the hydrogels by Fickian diffusion through the extramicellar aqueous channels of the gel matrix. Sodium chloride barely affected the dissolution mechanism or dissolution rate of the drug from the injectable gels. Furthermore, it maintained the plasma concentrations of drug for 4 days and gave a 150-fold higher AUC compared to piroxicam solution. Thus, it would be practically useful for delivering piroxicam in a pattern that allows sustained release for a long time, leading to better bioavailability.

  10. Incorporation of alpha-Ketoglutaric Acid as a Fixed Bed Scrubber Media for the Neutralization of Hydrazine Family Hypergolic Fuels

    Science.gov (United States)

    DeVor, R. W.; Santiago-Maldonado, E.; Parkerson, J. K.

    2010-01-01

    A candidate scrubber media, alpha-ketoglutaric acid (aKGA) adsorbed onto a silica-based substrate was examined as a potential alternative to the hydrazine-family hypergolic fuel neutralization techniques currently utilized at NASA/Kennedy Space Center (KSC). Helvenson et. al. has indicated that aKGA will react with hydrazines to produce non-hazardous, possibly biodegradable products. Furthermore, the authors have previously tested and demonstrated the use of aKGA aqueous solutions as a replacement neutralizing agent for citric acid, which is currently used as a scrubbing agent in liquid scrubbers at KSC. Specific properties examined include reaction efficiency, the loading capacity of aKGA onto various silica substrates, and the comparison of aKGA media performance to that of the citric acid vapor scrubber systems at KSC and a commercial vapor scrubber media. Preliminary investigations showed hydrophobic aerogel particles to be an ideal substrate for the deposition of the aKGA. Current studies have shown that the laboratory produced aKGA-Aerogel absorbent media are more efficient and cost effective than a commercially available fixed bed scrubber media, although much less cost effective than liquid-based citric acid scrubbers (although possibly safer and less labor intensive). A comparison of all three alternative scrubber technologies (liquid aKGA, solid-phase aKGA, and commercially available sorbent materials) is given considering both hypergolic neutralization capabilities and relative costs (as compared to the current citric acid scrubbing technology in use at NASA/KSC).

  11. Use of dimedone-based chemical probes for sulfenic acid detection evaluation of conditions affecting probe incorporation into redox-sensitive proteins.

    Science.gov (United States)

    Klomsiri, Chananat; Nelson, Kimberly J; Bechtold, Erika; Soito, Laura; Johnson, Lynnette C; Lowther, W Todd; Ryu, Seong-Eon; King, S Bruce; Furdui, Cristina M; Poole, Leslie B

    2010-01-01

    Sulfenic acids, formed as transient intermediates during the reaction of cysteine residues with peroxides, play significant roles in enzyme catalysis and regulation, and are also involved in the redox regulation of transcription factors and other signaling proteins. Therefore, interest in the identification of protein sulfenic acids has grown substantially in the past few years. Dimedone, which specifically traps sulfenic acids, has provided the basis for the synthesis of a novel group of compounds that derivatize 1,3-cyclohexadione, a dimedone analogue, with reporter tags such as biotin for affinity capture and fluorescent labels for visual detection. These reagents allow identification of the cysteine sites and proteins that are sensitive to oxidation and permit identification of the cellular conditions under which such oxidations occur. We have shown that these compounds are reactive and specific toward sulfenic acids and that the labeled proteins can be detected at high sensitivity using gel analysis or mass spectrometry. Here, we further characterize these reagents, showing that the DCP-Bio1 incorporation rates into three sulfenic acid containing proteins, papaya papain, Escherichia coli fRMsr, and the Salmonella typhimurium peroxiredoxin AhpC, are significantly different and, in the case of fRMsr, are unaffected by changes in buffer pH from 5.5 and 8.0. We also provide protocols to label protein sulfenic acids in cellular proteins, either by in situ labeling of intact cells or by labeling at the time of lysis. We show that the addition of alkylating reagents and catalase to the lysis buffer is critical in preventing the formation of sulfenic acid subsequent to cell lysis. Data presented herein also indicate that the need to standardize, as much as possible, the protein and reagent concentrations during labeling. Finally, we introduce several new test or control proteins that can be used to evaluate labeling procedures and efficiencies.

  12. Enhanced bone formation in electrospun poly(L-lactic-co-glycolic acid)-tussah silk fibroin ultrafine nanofiber scaffolds incorporated with graphene oxide.

    Science.gov (United States)

    Shao, Weili; He, Jianxin; Sang, Feng; Wang, Qian; Chen, Li; Cui, Shizhong; Ding, Bin

    2016-05-01

    To engineer bone tissue, it is necessary to provide a biocompatible, mechanically robust scaffold. In this study, we fabricated an ultrafine nanofiber scaffold by electrospinning a blend of poly(L-lactic-co-glycolic acid), tussah silk fibroin, and graphene oxide (GO) and characterized its morphology, biocompatibility, mechanical properties, and biological activity. The data indicate that incorporation of 10 wt.% tussah silk and 1 wt.% graphene oxide into poly(L-lactic-co-glycolic acid) nanofibers significantly decreased the fiber diameter from 280 to 130 nm. Furthermore, tussah silk and graphene oxide boosted the Young's modulus and tensile strength by nearly 4-fold and 3-fold, respectively, and significantly enhanced adhesion, proliferation in mouse mesenchymal stem cells and functionally promoted biomineralization-relevant alkaline phosphatase (ALP) and mineral deposition. The results indicate that composite nanofibers could be excellent and versatile scaffolds for bone tissue engineering.

  13. Incorporation of a lauric acid-conjugated GRGDS peptide directly into the matrix of a poly(carbonate-urea)urethane polymer for use in cardiovascular bypass graft applications.

    Science.gov (United States)

    Kidane, Asmeret G; Punshon, Geoffrey; Salacinski, Henryk J; Ramesh, Bala; Dooley, Audrey; Olbrich, Michael; Heitz, Johannes; Hamilton, George; Seifalian, Alexander M

    2006-12-01

    Gly-Arg-Gly-Asp-Ser (GRGDS) was modified by conjugation to lauric acid (LA) to facilitate incorporation into the matrix of a poly(carbonate-urea)urethane (PCU) used in vascular bypass grafts. GRGDS and LA-GRGDS were synthesized using solid phase Fmoc chemistry and characterized by high performance liquid chromatography and Fourier transform infrared spectroscopy. LA-GRGDS was passively coated and incorporated as nanoparticle dispersion on the PCU films. Biocompatibility of the modified surfaces was investigated. Endothelial cells seeded on LA-GRGDS coated and incorporated PCU showed after 48 h and 72 h a significant (p < 0.05) increase in metabolism compared with unmodified PCU. The platelet adhesion and hemolysis studies showed that the modification of PCU had no adverse effect. In conclusion, LA-conjugated RGD derivatives, such as LA-GRGDS, that permit solubility into solvents used in solvent casting methodologies should have wide applicability in polymer development for use in coronary, vascular, and dialysis bypass grafts, and furthermore scaffolds utilized for tissue regeneration and tissue engineering.

  14. Increased axonal regeneration through a biodegradable amnionic tube nerve conduit: effect of local delivery and incorporation of nerve growth factor/hyaluronic acid media.

    Science.gov (United States)

    Mohammad, J A; Warnke, P H; Pan, Y C; Shenaq, S

    2000-01-01

    The authors emphasize the possible pharmacological enhancement of axonal regeneration using a specific growth factor/ extracellular media incorporated in a biodegradable nonneural nerve conduit material. They investigated the early effects on nerve regeneration of continuous local delivery of nerve growth factor (NGF) and the local incorporation of hyaluronic acid (HA) inside a newly manufactured nerve conduit material from fresh human amnionic membrane. Human amnionic membrane contains important biochemical factors that play a major neurotrophic role in the nerve regeneration process. The process of manufacturing a nerve conduit from fresh human amnionic membrane is described. This nerve conduit system was used in rabbits to bridge a 25-mm nerve gap over 3 months. NGF was released locally, over 28 days, at the distal end of the tube via a system of slow release, and HA was incorporated inside the lumen of the tube at the time of surgery. NGF/HA treatment promoted axonal regeneration across the amnionic tube nerve conduit (8,962 +/- 383 myelinated axons) 45% better than the nontreated amnionic tube group (6,180 +/- 353 myelinated axons). The authors demonstrate that NGF/HA media enhances additional axonal regeneration in the amnionic tube nerve conduit. This result is secondary to the effect of the amnion promoting biochemical factors, in combination with the NGF/HA effect on facilitating early events in the nerve regeneration process.

  15. Reduction of inflammatory responses and enhancement of extracellular matrix formation by vanillin-incorporated poly(lactic-co-glycolic acid) scaffolds.

    Science.gov (United States)

    Lee, Yujung; Kwon, Jeongil; Khang, Gilson; Lee, Dongwon

    2012-10-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting in the higher cell attachment and proliferation than the pure PLGA film. Vanillin also reduced the generation of reactive oxygen species (ROS) in cells cultured on the pure PLGA film and significantly inhibited the PLGA-induced inflammatory responses in vivo, evidenced by the reduced accumulation of inflammatory cells and thinner fibrous capsules. The effects of vanillin on the ECM formation were evaluated using annulus fibrous (AF) cell-seeded porous PLGA/vanillin scaffolds. PLGA/vanillin scaffolds elicited the more production of glycosaminoglycan and collagen than the pure PLGA scaffold, in a concentration-dependent manner. Based on the low level of inflammatory responses and enhanced ECM formation, vanillin-incorporated PLGA constructs make them promising candidates in the future biomedical applications.

  16. Improving oxidative stability of olive oil: Incorporation of Spirulina and evaluation of its synergism with citric acid

    Directory of Open Access Journals (Sweden)

    N. Alavi

    2017-03-01

    Full Text Available The effects of different Spirulina concentrations used alone and in combination with citric acid on the oxidative stability of olive oil were assessed. The amounts of primary and secondary oxidation products produced in Spirulina samples were lower than that of the control. The improved oxidative stability indices of Spirulina samples with and without citric acid were in the range of 85.20–94.47% and 258.10–260.21%, respectively. In comparison with the control, Spirulina samples manifested significantly higher carotenoid and chlorophyll contents at the beginning and end of the storage period. The presence of these bioactive compounds results from the presence of Spirulina in the medium and can thus retard the oxidation of olive oil. A higher oxidative stability was reached using BHT in comparison with Spirulina samples. Furthermore, no synergistic action was observed in possible connections between citric acid and Spirulina. In conclusion, Spirulina can enhance oxidative stability and improve the shelf life of olive oil.

  17. C-H bond strengths and acidities in aromatic systems: effects of nitrogen incorporation in mono-, di-, and triazines.

    Science.gov (United States)

    Wren, Scott W; Vogelhuber, Kristen M; Garver, John M; Kato, Shuji; Sheps, Leonid; Bierbaum, Veronica M; Lineberger, W Carl

    2012-04-18

    The negative ion chemistry of five azine molecules has been investigated using the combined experimental techniques of negative ion photoelectron spectroscopy to obtain electron affinities (EA) and tandem flowing afterglow-selected ion tube (FA-SIFT) mass spectrometry to obtain deprotonation enthalpies (Δ(acid)H(298)). The measured Δ(acid)H(298) for the most acidic site of each azine species is combined with the EA of the corresponding radical in a thermochemical cycle to determine the corresponding C-H bond dissociation energy (BDE). The site-specific C-H BDE values of pyridine, 1,2-diazine, 1,3-diazine, 1,4-diazine, and 1,3,5-triazine are 110.4 ± 2.0, 111.3 ± 0.7, 113.4 ± 0.7, 107.5 ± 0.4, and 107.8 ± 0.7 kcal mol(-1), respectively. The application of complementary experimental methods, along with quantum chemical calculations, to a series of nitrogen-substituted azines sheds light on the influence of nitrogen atom substitution on the strength of C-H bonds in six-membered rings.

  18. Docetaxel-loaded polylactic acid-co-glycolic acid nanoparticles: formulation, physicochemical characterization and cytotoxicity studies.

    Science.gov (United States)

    Pradhan, Roshan; Poudel, Bijay Kumar; Ramasamy, Thiruganesh; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

    2013-08-01

    In the present study, we developed novel docetaxel (DTX)-loaded polylactic acid-co-glycolic acid (PLGA) nanoparticles (NPs) using the combination of sodium lauryl sulfate (SLS) and poloxamer 407, the anionic and non-ionic surfactants respectively for stabilization. The NPs were prepared by emulsification/solvent evaporation method. The combination of these surfactants at weight ratio of 1:0.5 was able to produce uniformly distributed small sized NPs and demonstrated the better stability of NP dispersion with high encapsulation efficiency (85.9 +/- 0.6%). The drug/polymer ratio and phase ratio were 2:10 and 1:10, respectively. The optimized formulation of DTX-loaded PLGA NPs had a particle size and polydispersity index of 104.2 +/- 1.5 nm and 0.152 +/- 0.006, respectively, which was further supported by TEM image. In vitro release study was carried out with dialysis membrane and showed 32% drug release in 192 h. When in vitro release data were fitted to Korsmeyer-Peppas model, the n value was 0.481, which suggested the drug was released by anomalous or non-Fickian diffusion. In addition, DTX-loaded PLGA NPs in 72 h, displayed approximately 75% cell viability reduction at 10 microg/ml DTX concentration, in MCF-7 cell lines, indicating sustained release from NPs. Therefore, our results demonstrated that incorporation of DTX into PLGA NPs could provide a novel effective nanocarrier for the treatment of cancer.

  19. Enhanced bone formation in electrospun poly(L-lactic-co-glycolic acid)–tussah silk fibroin ultrafine nanofiber scaffolds incorporated with graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Weili [Key Laboratory of Advanced Textile Composites (Ministry of Education), Institute of Textile Composites, Tianjin Polytechnic University, Tianjin 300387 (China); Henan Provincial Key Laboratory of Functional Textile Materials, Zhongyuan University of Technology, Zhengzhou 450007 (China); He, Jianxin, E-mail: hejianxin771117@163.com [Henan Provincial Key Laboratory of Functional Textile Materials, Zhongyuan University of Technology, Zhengzhou 450007 (China); Sang, Feng [Department of Acquired Immune Deficiency Syndrome Treatment and Research Center, The First Affiliated Hospital of Henan University of Traditional Chinese Medicine, Zhengzhou 450000 (China); Wang, Qian [Henan Provincial Key Laboratory of Functional Textile Materials, Zhongyuan University of Technology, Zhengzhou 450007 (China); Chen, Li [Key Laboratory of Advanced Textile Composites (Ministry of Education), Institute of Textile Composites, Tianjin Polytechnic University, Tianjin 300387 (China); Cui, Shizhong [Key Laboratory of Advanced Textile Composites (Ministry of Education), Institute of Textile Composites, Tianjin Polytechnic University, Tianjin 300387 (China); Henan Provincial Key Laboratory of Functional Textile Materials, Zhongyuan University of Technology, Zhengzhou 450007 (China); Ding, Bin [Henan Provincial Key Laboratory of Functional Textile Materials, Zhongyuan University of Technology, Zhengzhou 450007 (China); State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201600 (China)

    2016-05-01

    To engineer bone tissue, it is necessary to provide a biocompatible, mechanically robust scaffold. In this study, we fabricated an ultrafine nanofiber scaffold by electrospinning a blend of poly(L-lactic-co-glycolic acid), tussah silk fibroin, and graphene oxide (GO) and characterized its morphology, biocompatibility, mechanical properties, and biological activity. The data indicate that incorporation of 10 wt.% tussah silk and 1 wt.% graphene oxide into poly(L-lactic-co-glycolic acid) nanofibers significantly decreased the fiber diameter from 280 to 130 nm. Furthermore, tussah silk and graphene oxide boosted the Young's modulus and tensile strength by nearly 4-fold and 3-fold, respectively, and significantly enhanced adhesion, proliferation in mouse mesenchymal stem cells and functionally promoted biomineralization-relevant alkaline phosphatase (ALP) and mineral deposition. The results indicate that composite nanofibers could be excellent and versatile scaffolds for bone tissue engineering. - Highlights: • GO-doped PLGA–tussah silk fibroin ultrafine nanofibers with diameter of about 130 nm were fabricated by electrospinning. • Incorporation of 10 wt.% tussah silk to the PLGA nanofibers accelerates osteoblast differentiation and formation of new bone. • Mechanical properties of composite nanofiber mats had been significantly improved after embedding with GO nanosheets. • Nanostructured composite scaffolds effectively accelerate mesenchymal stem cells differentiation and formation of new bone.

  20. Activite succino-deshydrogenasique des microsomes et mode d'incorporation du succinate 2,3-(14)C dans les acides gras des microsomes de foie de rat in vitro.

    Science.gov (United States)

    Rous, S; Aubry, L; Bonini, F

    1970-03-16

    The incorporations of 2,3-(14)C-succinate 2-(14)C-acetate into fatty acids of different cellular fractions of rat liver were studied. Acetate was incorporated mainly into supernatant and succinate into microsomal fatty acids. Mitochondria only could intensively decarboxylate pyruvate. Avidine inhibited fatty acid synthesis from succinate mainly in the supernatant. It is suggested that succinate is an important physiological precursor of fatty acids in the liver and that an active succino-dehydrogenase is present in microsomes.

  1. Facile fabrication of poly(L-lactic acid) microsphere-incorporated calcium alginate/hydroxyapatite porous scaffolds based on Pickering emulsion templates.

    Science.gov (United States)

    Hu, Yang; Ma, Shanshan; Yang, Zhuohong; Zhou, Wuyi; Du, Zhengshan; Huang, Jian; Yi, Huan; Wang, Chaoyang

    2016-04-01

    In this study, we develop a facile one-pot approach to the fabrication of poly(L-lactic acid) (PLLA) microsphere-incorporated calcium alginate (ALG-Ca)/hydroxyapatite (HAp) porous scaffolds based on HAp nanoparticle-stabilized oil-in-water Pickering emulsion templates, which contain alginate in the aqueous phase and PLLA in the oil phase. The emulsion aqueous phase is solidified by in situ gelation of alginate with Ca(2+) released from HAp by decreasing pH with slow hydrolysis of D-gluconic acid δ-lactone (GDL) to produce emulsion droplet-incorporated gels, followed by freeze-drying to form porous scaffolds containing microspheres. The pore structure of porous scaffolds can be adjusted by varying the HAp or GDL concentration. The compressive tests show that the increase of HAp or GDL concentration is beneficial to improve the compressive property of porous scaffolds, while the excessive HAp can lead to the decrease in compressive property. Moreover, the swelling behavior studies display that the swelling ratios of porous scaffolds reduce with increasing HAp or GDL concentration. Furthermore, hydrophobic drug ibuprofen (IBU) and hydrophilic drug bovine serum albumin (BSA) are loaded into the microspheres and scaffold matrix, respectively. In vitro drug release results indicate that BSA has a rapid release while IBU has a sustained release in the dual drug-loaded scaffolds. In vitro cell culture experiments verify that mouse bone mesenchymal stem cells can proliferate on the porous scaffolds well, indicating the good biocompatibility of porous scaffolds. All these results demonstrate that the PLLA microsphere-incorporated ALG-Ca/HAp porous scaffolds have a promising potential for tissue engineering and drug delivery applications.

  2. Comparative study of poly (lactic-co-glycolic acid/tricalcium phosphate scaffolds incorporated or coated with osteogenic growth factors for enhancement of bone regeneration

    Directory of Open Access Journals (Sweden)

    Shi-hui Chen

    2014-04-01

    Full Text Available Bone graft substitutes are commonly used to treat large bone defects, particularly if they can additionally act as a local delivery system for therapeutic agents capable of enhancing bone regeneration. In this study, composite scaffolds made of poly (lactic-co-glycolic acid (PLGA and tricalcium phosphate (TCP called P/T were fabricated by a low-temperature rapid prototyping technique. In order to optimise the delivery system, two different approaches for loading either the phytomolecule icaritin (ICT or bone morphogenetic protein-2 (BMP-2 were developed for an in vivo efficacy study. One was an “incorporating approach” in which the growth factor was incorporated into the scaffold during fabrication, whereas the other was a “coating approach” in which the fabricated scaffold was immersed into a preparative solution containing the growth factor. Scaffolds incorporating these growth factors were termed P/T/ICT and P/T/BMP-2, while scaffolds that had these growth factors coated on to them were named, respectively, P/T + ICT and P/T + BMP-2. A P/T scaffold without any loading was used as the control. The bone regeneration effect of these scaffolds was compared in an ulnar bone defect model in rabbits. Bone regeneration and angiogenesis was evaluated by high-resolution peripheral quantitative computed tomography and magnetic resonance imaging postimplantation. Bone regeneration was better with the P/T/ICT scaffolds with an 83.8% improvement compared with the control, and a 72.0% improvement compared with the P/T/BMP-2 treatment. Although the P/T + BMP-2 scaffold demonstrated, as expected, the best overall bone regeneration, the P/T scaffold with incorporated ICT was shown to be an innovative and cost-effective bioactive scaffold which also significantly enhanced bone regeneration with the potential to be validated for orthopaedic applications.

  3. Bacteriostatic and anti-collagenolytic dental materials through the incorporation of polyacrylic acid modified CuI nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Renne, Walter George; Mennito, Anthony Samuel; Schmidt, Michael Gerard; Vuthiganon, Jompobe; Chumanov, George

    2015-05-19

    Provided are antibacterial and antimicrobial surface coatings and dental materials by utilizing the antimicrobial properties of copper chalcogenide and/or copper halide (CuQ, where Q=chalcogens including oxygen, or halogens, or nothing). An antimicrobial barrier is created by incorporation of CuQ nanoparticles of an appropriate size and at a concentration necessary and sufficient to create a unique bioelectrical environment. The unique bioelectrical environment results in biocidal effectiveness through a multi-factorial mechanism comprising a combination of the intrinsic quantum flux of copper (Cu.sup.0, Cu.sup.1+, Cu.sup.2+) ions and the high surface-to-volume electron sink facilitated by the nanoparticle. The result is the constant quantum flux of copper which manifests and establishes the antimicrobial environment preventing or inhibiting the growth of bacteria. The presence of CuQ results in inhibiting or delaying bacterial destruction and endogenous enzymatic breakdown of the zone of resin inter-diffusion, the integrity of which is essential for dental restoration longevity.

  4. Designing improved poly lactic-co-glycolic acid microspheres for a malarial vaccine: incorporation of alginate and polyinosinic-polycytidilic acid.

    Science.gov (United States)

    Salvador, Aiala; Igartua, Manoli; Hernández, Rosa María; Pedraz, José Luis

    2014-01-01

    Vaccination using proteins and peptides is currently gaining importance. One of the major drawbacks of this approach is the lack of an efficient immune response when the antigens are administered without adjuvants. In this study, we have taken the advantage of a combined adjuvant system in order to improve the immunogenicity of the SPf66 malarial antigen. For that purpose, we have combined poly (lactic-co-glycolic) acid microspheres, alginate, and polyinosinic polycytidilic acid. Our results show that microspheres can enhance the IgG production obtained with Freund's complete adjuvant. We have attributed this improvement to the presence of polyinosinic polycytidilic acid, since formulations comprising this adjuvant overcame the immune response from the others. In addition, our microspheres produced both IgG1 and IgG2a, leading to mixed Th1/Th2 activation, optimal for malaria vaccination. In conclusion, we have designed a preliminary formulation with a high potential for the treatment of malaria.

  5. Synthesis and carbonic anhydrase inhibitory properties of amino acid - coumarin/quinolinone conjugates incorporating glycine, alanine and phenylalanine moieties.

    Science.gov (United States)

    Küçükbay, F Zehra; Küçükbay, Hasan; Tanc, Muhammet; Supuran, Claudiu T

    2016-12-01

    N-Protected amino acids (Gly, Ala and Phe) were reacted with amino substituted coumarin and quinolinone derivatives, leading to the corresponding N-protected amino acid-coumarin/quinolinone conjugates. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against various human (h) isoforms, such as hCA I, hCA II, hCA IV and hCA XII. The quinolinone conjugates were inactive as enzyme inhibitors, whereas the coumarins were ineffective hCA I/II inhibitors (KIs > 50 μM) but were submicromolar hCA IV and XII inhibitors, with inhibition constants ranging between 92 nM and 1.19 μM for hCA IV, and between 0.11 and 0.79 μM for hCA XII. These coumarin derivatives, as many others reported earlier, thus show an interesting selective inhibitory profile for the membrane-bound over the cytosolic CA isoforms.

  6. Evaluation of antibacterial activity of whey protein isolate coating incorporated with nisin, grape seed extract, malic acid, and EDTA on a Turkey frankfurter system.

    Science.gov (United States)

    Gadang, V P; Hettiarachchy, N S; Johnson, M G; Owens, C

    2008-10-01

    The effectiveness of whey protein isolate (WPI) coatings incorporated with grape seed extract (GSE), nisin (N), malic acid (MA), and ethylenediamine tetraacetic acid (EDTA) and their combinations to inhibit the growth of Listeria monocytogenes, E. coli O157:H7, and Salmonella typhimurium were evaluated in a turkey frankfurter system through surface inoculation (approximately 10(6) CFU/g) of pathogens. The inoculated frankfurters were dipped into WPI film forming solutions both with and without the addition of antimicrobial agents (GSE, MA, or N and EDTA, or combinations). Samples were stored at 4 degrees C for 28 d. The L. monocytogenes population (5.5 log/g) decreased to 2.3 log/g after 28 d at 4 degrees C in the samples containing nisin (6000 IU/g) combined with GSE (0.5%) and MA (1.0%). The S. typhimurium population (6.0 log/g) was decreased to approximately 1 log cycles after 28 d at 4 degrees C in the samples coated with WPI containing a combination of N, MA, GSE, and EDTA. The E. coli O157:H7 population (6.15 log/g) was decreased by 4.6 log cycles after 28 d in samples containing WPI coating incorporated with N, MA, and EDTA. These findings demonstrated that the use of an edible film coating containing nisin, organic acids, and natural extracts is a promising means of controlling the growth and recontamination of L. monocytogenes, S. typhimurium, and E. coli O157:H7 in ready-to-eat poultry products.

  7. Incorporating significant amino acid pairs and protein domains to predict RNA splicing-related proteins with functional roles

    Science.gov (United States)

    Hsu, Justin Bo-Kai; Huang, Kai-Yao; Weng, Tzu-Ya; Huang, Chien-Hsun; Lee, Tzong-Yi

    2014-01-01

    Machinery of pre-mRNA splicing is carried out through the interaction of RNA sequence elements and a variety of RNA splicing-related proteins (SRPs) (e.g. spliceosome and splicing factors). Alternative splicing, which is an important post-transcriptional regulation in eukaryotes, gives rise to multiple mature mRNA isoforms, which encodes proteins with functional diversities. However, the regulation of RNA splicing is not yet fully elucidated, partly because SRPs have not yet been exhaustively identified and the experimental identification is labor-intensive. Therefore, we are motivated to design a new method for identifying SRPs with their functional roles in the regulation of RNA splicing. The experimentally verified SRPs were manually curated from research articles. According to the functional annotation of Splicing Related Gene Database, the collected SRPs were further categorized into four functional groups including small nuclear Ribonucleoprotein, Splicing Factor, Splicing Regulation Factor and Novel Spliceosome Protein. The composition of amino acid pairs indicates that there are remarkable differences among four functional groups of SRPs. Then, support vector machines (SVMs) were utilized to learn the predictive models for identifying SRPs as well as their functional roles. The cross-validation evaluation presents that the SVM models trained with significant amino acid pairs and functional domains could provide a better predictive performance. In addition, the independent testing demonstrates that the proposed method could accurately identify SRPs in mammals/plants as well as effectively distinguish between SRPs and RNA-binding proteins. This investigation provides a practical means to identifying potential SRPs and a perspective for exploring the regulation of RNA splicing.

  8. Incorporating significant amino acid pairs and protein domains to predict RNA splicing-related proteins with functional roles.

    Science.gov (United States)

    Hsu, Justin Bo-Kai; Huang, Kai-Yao; Weng, Tzu-Ya; Huang, Chien-Hsun; Lee, Tzong-Yi

    2014-01-01

    Machinery of pre-mRNA splicing is carried out through the interaction of RNA sequence elements and a variety of RNA splicing-related proteins (SRPs) (e.g. spliceosome and splicing factors). Alternative splicing, which is an important post-transcriptional regulation in eukaryotes, gives rise to multiple mature mRNA isoforms, which encodes proteins with functional diversities. However, the regulation of RNA splicing is not yet fully elucidated, partly because SRPs have not yet been exhaustively identified and the experimental identification is labor-intensive. Therefore, we are motivated to design a new method for identifying SRPs with their functional roles in the regulation of RNA splicing. The experimentally verified SRPs were manually curated from research articles. According to the functional annotation of Splicing Related Gene Database, the collected SRPs were further categorized into four functional groups including small nuclear Ribonucleoprotein, Splicing Factor, Splicing Regulation Factor and Novel Spliceosome Protein. The composition of amino acid pairs indicates that there are remarkable differences among four functional groups of SRPs. Then, support vector machines (SVMs) were utilized to learn the predictive models for identifying SRPs as well as their functional roles. The cross-validation evaluation presents that the SVM models trained with significant amino acid pairs and functional domains could provide a better predictive performance. In addition, the independent testing demonstrates that the proposed method could accurately identify SRPs in mammals/plants as well as effectively distinguish between SRPs and RNA-binding proteins. This investigation provides a practical means to identifying potential SRPs and a perspective for exploring the regulation of RNA splicing.

  9. Physicochemical features and transfection properties of chitosan/poloxamer 188/poly(D,L-lactide-co-glycolide nanoplexes

    Directory of Open Access Journals (Sweden)

    Cosco D

    2014-05-01

    Full Text Available Donato Cosco,1,5,* Cinzia Federico,1,2,* Jessica Maiuolo,1 Stefania Bulotta,1 Roberto Molinaro,1,3 Donatella Paolino,1,5 Pierfrancesco Tassone,2,4 Massimo Fresta1Department of Health Sciences, 2Department of Experimental and Clinical Medicine, University Magna Græcia of Catanzaro, Catanzaro, Italy; 3Department of NanoMedicine, The Methodist Research Institute, Houston, TX, USA; 4Medical Oncology, Tommaso Campanella Cancer Center, Viale S Venuta, Germaneto, 5Interregional Research Center for Food Safety and Health, University of Catanzaro “Magna Græcia”, Catanzaro, Italy*These authors contributed equally to this paperAbstract: The aim of this study was the evaluation of the effects of two emulsifiers on the physicochemical and technological properties of low molecular weight chitosan/poly (D,L-lactide-co-glycolide (PLGA nanoplexes and their transfection efficiency. Nanospheres were prepared using the nanoprecipitation method of the preformed polymer. The mean diameter and surface charge of the nanospheres were investigated by photocorrelation spectroscopy. The degree of binding of the plasmid with the nanoplexes was qualitatively and quantitatively determined. MTT (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide testing was performed using HeLa, RPMI8226, and SKMM1 cell lines. Flow cytometry and confocal laser scanning microscopy were used to determine the degree of cellular transfection and internalization of the nanoplexes into cells, respectively. The nanoplexes had a positive zeta potential, and low amounts of PLGA and poloxamer 188 showed a mean colloidal size of ~200 nm with a polydispersity index of ~0.14. The nanoplexes had suitable entrapment efficiency (80%. In vitro experiments showed that the colloidal nanodevices did not induce significant cytotoxicity. The nanoplexes investigated in this study could represent efficient and useful nonviral devices for gene delivery. Use of low amounts of PLGA and poloxamer 188

  10. Enhanced proton conductivity of Nafion hybrid membrane under different humidities by incorporating metal-organic frameworks with high phytic acid loading.

    Science.gov (United States)

    Li, Zhen; He, Guangwei; Zhang, Bei; Cao, Ying; Wu, Hong; Jiang, Zhongyi; Tiantian, Zhou

    2014-06-25

    In this study, phytic acid (myo-inositol hexaphosphonic acid) was first immobilized by MIL101 via vacuum-assisted impregnation method. The obtained phytic@MIL101 was then utilized as a novel filler to incorporate into Nafion to fabricate hybrid proton exchange membrane for application in PEMFC under different relative humidities (RHs), especially under low RHs. High loading and uniform dispersion of phytic acid in MIL 101(Cr) were achieved as demonstrated by ICP, FT-IR, XPS, and EDS-mapping. The phytic@MIL101 was dispersed homogeneously in the Nafion matrix when the filler content was less than 12%. Hybrid membranes were evaluated by proton conductivity, mechanical property, thermal stability, and so forth. Remarkably, the Nafion/phytic@MIL hybrid membranes showed high proton conductivity at different RHs, especially under low RHs, which was up to 0.0608 S cm(-1) and 7.63 × 10(-4) S cm(-1) at 57.4% RH and 10.5% RH (2.8 and 11.0 times higher than that of pristine membrane), respectively. Moreover, the mechanical property of Nafion/phtic@MIL hybrid membranes was substantially enhanced and the thermal stability of membranes was well preserved.

  11. A novel binuclear copper complex incorporating a nalidixic acid derivative displaying a one-dimensional coordination polymeric structure.

    Science.gov (United States)

    Bergamini, F R G; Ribeiro, M A; Miranda, P C M L; Formiga, A L B; Corbi, P P

    2016-07-01

    The identification of the antibacterial action of nalidixic acid (nx) was central to the development of the quinolone antibacterial compounds. The ability of the nx naphthyridyl ring to interact with and inhibit some proteins has encouraged the investigation of similar structures in the search for more active compounds with less adverse effects. The possibility of structural modification by attachment of other biologically active moieties to the naphthyridyl ring of nx allowed the development of new active antimicrobial molecules. Hydrazone derivatives of nx can be synthesized easily based on the condensation of the hydrazide derivative of nx with the desired aldehyde or ketone. Only a few complexes with nx hydrazone derivatives have been described but for none were the crystal structures elucidated. The synthesis of a new one-dimensional Cu(II) coordination polymer, namely catena-poly[[copper(II)-di-μ-chlorido-copper(II)-{μ-1-ethyl-N'-[(1H-imidazol-4-yl)methylidene]-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazidato}-[dimethanolcopper(II)]-{μ-1-ethyl-N'-[(1H-imidazol-3-yl)methylidene]-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazidato}] dichloride methanol tetrasolvate], {[Cu3(C16H15N6O2)2Cl2(CH3OH)2]Cl2·4CH3OH}n, with the (1H-imidazol-4-yl)methylidene carbohydrazide derivative of nalidixic acid (denoted h4imi), is presented and its structure is compared to the density functional theory (DFT) optimized structure of free h4imi. The title structure presents an octahedral Cu(II) ion on an inversion centre alternating along a polymer chain with a square-pyramidal Cu(II) ion, with the two Cu(II) centres bridged by two chloride ligands. Hydrogen bonds involving chloride counter-ions and methanol solvent molecules mediate the three-dimensional packing of the polymer. Comparison of the geometrical results from the structure analysis with those derived from a DFT study of the free ligand reveal the differences that arise upon coordination.

  12. Synthesis, photophysical properties of triazolyl-donor/acceptor chromophores decorated unnatural amino acids: Incorporation of a pair into Leu-enkephalin peptide and application of triazolylperylene amino acid in sensing BSA.

    Science.gov (United States)

    Bag, Subhendu Sekhar; Jana, Subhashis; Pradhan, Manoj Kumar

    2016-08-15

    The research in the field of design and synthesis of unnatural amino acids is growing at a fast space for the increasing demand of proteins of potential therapeutics and many other diversified novel functional applications. Thus, we report herein the design and synthesis of microenvironment sensitive fluorescent triazolyl unnatural amino acids (UNAA) decorated with donor and/or acceptor aromatic chromophores via click chemistry. The synthesized fluorescent amino acids show interesting solvatochromic characteristic and/or intramolecular charge transfer (ICT) feature as is revealed from the UV-visible, fluorescence photophysical properties and DFT/TDDFT calculation. HOMO-LUMO distribution shows that the emissive states of some of the amino acids are characterized with more significant electron redistribution between the triazolyl moiety and the aromatic chromophores linked to it leading to modulated emission property. A pair of donor-acceptor amino acid shows interesting photophysical interaction property indicating a FRET quenching event. Furthermore, one of the amino acid, triazolyl-perylene amino acid, has been exploited for studying interaction with BSA and found that it is able to sense BSA with an enhancement of fluorescence intensity. Finally, we incorporated a pair of donor/acceptor amino acids into a Leu-enkephalin analogue pentapeptide which was found to adopt predominantly type II β-turn conformation. We envisage that our investigation is of importance for the development of new fluorescent donor-acceptor unnatural amino acids a pair of which can be exploited for generating fluorescent peptidomimetic probe of interesting photophysical property for applications in studying peptide-protein interaction.

  13. Identifying the Types of Ion Channel-Targeted Conotoxins by Incorporating New Properties of Residues into Pseudo Amino Acid Composition

    Directory of Open Access Journals (Sweden)

    Yun Wu

    2016-01-01

    Full Text Available Conotoxins are a kind of neurotoxin which can specifically interact with potassium, sodium type, and calcium channels. They have become potential drug candidates to treat diseases such as chronic pain, epilepsy, and cardiovascular diseases. Thus, correctly identifying the types of ion channel-targeted conotoxins will provide important clue to understand their function and find potential drugs. Based on this consideration, we developed a new computational method to rapidly and accurately predict the types of ion-targeted conotoxins. Three kinds of new properties of residues were proposed to use in pseudo amino acid composition to formulate conotoxins samples. The support vector machine was utilized as classifier. A feature selection technique based on F-score was used to optimize features. Jackknife cross-validated results showed that the overall accuracy of 94.6% was achieved, which is higher than other published results, demonstrating that the proposed method is superior to published methods. Hence the current method may play a complementary role to other existing methods for recognizing the types of ion-target conotoxins.

  14. EPR and optical studies of VO2+ doped potassium succinate-succinic acid single crystal - Substitutional incorporation

    Science.gov (United States)

    Juliet sheela, K.; Radha Krishnan, S.; Shanmugam, V. M.; Subramanian, P.

    2017-03-01

    EPR and optical absorption studies of VO2+ doped potassium succinate-succinic acid (KSSA) single crystal has been examined at room temperature. EPR spectrum shows that well resolved hyperfine lines. The angular variation of the EPR spectra has shown that two different VO2+ complexes are located in different chemical environments. Among the number of sites, two sites have been followed and reported here. From the EPR analysis, spin Hamiltonian parameters g and A tensors and their directional cosines are evaluated. Both the sites experience rhombic crystal field symmetry around the impurity ion. The VO2+ ion entering the site location of potassium ion has coordination of eight oxygen atoms in a distorted dodecahedral arrangement. The Optical absorption spectrum studied at room temperature shows bands corresponding to C4v symmetry. The crystal field parameter and tetragonal field parameters are calculated. From the Optical and EPR data various molecular orbital coefficients are evaluated and the nature of bonding in the crystal is discussed.

  15. In vitro characteristics of poly(lactic-co-glycolic acid) microspheres incorporating gelatin particles loading basic fibroblast growth factor

    Institute of Scientific and Technical Information of China (English)

    Shao-hong LI; Shao-xi CAI; Bing LIU; Kai-wang MA; Zhen-ping WANG; Xiao-kun LI

    2006-01-01

    Aim: To construct a sustained drug release system for basic fibroblast growth factor (bFGF). With this special system, bFGF can be used to repair an injured peripheral nerve, injured spinal cord, or as a carrier for other drugs that need to be released over a long time. Methods: Microsphere composite was prepared by encapsulating bFGF into gelatin particles with poly(lactic-co-glycolic acid) (PLGA) as its outer-coating. The encapsulation was conducted by a phase separation method. Results: The average diameter of the gelatin particle-PLGA microsphere composite was 5-18 μm, and bFGF-loading efficiency was up to 80.5%. The bFGF releasing experiment indicated that this new composite system could release bFGF continuously and protect bFGF from denaturation. Conclusion: A modified approach was successfully employed to develop a biodegradable system for sustained release of the drug of bFGF in vitro.

  16. The chain length of lignan macromolecule from flaxseed hulls is determined by the incorporation of coumaric acid glucosides and ferulic acid glucosides.

    Science.gov (United States)

    Struijs, Karin; Vincken, Jean-Paul; Doeswijk, Timo G; Voragen, Alphons G J; Gruppen, Harry

    2009-01-01

    Lignan macromolecule from flaxseed hulls is composed of secoisolariciresinol diglucoside (SDG) and herbacetin diglucoside (HDG) moieties ester-linked by 3-hydroxy-3-methylglutaric acid (HMGA), and of p-coumaric acid glucoside (CouAG) and ferulic acid glucoside (FeAG) moieties ester-linked directly to SDG. The linker molecule HMGA was found to account for 11% (w/w) of the lignan macromolecule. Based on the extinction coefficients and RP-HPLC data, it was determined that SDG contributes for 62.0% (w/w) to the lignan macromolecule, while CouAG, FeAG, and HDG contribute for 12.2, 9.0, and 5.7% (w/w), respectively. Analysis of fractions of lignan macromolecule showed that the higher the molecular mass, the higher the proportion of SDG was. An inverse relation between the molecular mass and the proportion (%) CouAG+FeAG was found. Together with the structural information of oligomers of lignan macromolecule obtained after partial saponification, it is hypothesized that the amount of CouAG+FeAG present during biosynthesis determines the chain length of lignan macromolecule. Furthermore, the chain length was estimated from a model describing lignan macromolecule based on structural and compositional data. The average chain length of the lignan macromolceule was calculated to be three SDG moieties with CouAG or FeAG at each of the terminal positions, with a variation between one and seven SDG moieties.

  17. Modified thermoresponsive Poloxamer 407 and chitosan sol-gels as potential sustained-release vaccine delivery systems

    DEFF Research Database (Denmark)

    Kojarunchitt, Thunjiradasiree; Baldursdottir, Stefania; Dong, Yao-Da

    2015-01-01

    Thermoresponsive, particle-loaded, Poloxamer 407 (P407)-Pluronic-R® (25R4) or chitosan-methyl cellulose (MC) formulations were developed as single-dose, sustained release vaccines. The sol-gels, loaded either with a particulate vaccine (cubosomes) or soluble antigen (ovalbumin) and adjuvants (Quil...... the chitosan-MC sol-gels sustained the release of antigen up to at least 14 days after administration. The chitosan-MC sol-gels stimulated both cellular and humoral responses. The inclusion of cubosomes in the sol-gels did not provide a definitive beneficial effect. Further analysis of the formulations...... with small-angle X-ray scattering (SAXS) revealed that while cubosomes were stable in chitosan-MC gels they were not stable in P407-25R4 formulations. The reason for the mixed response to cubosome-loaded vehicles requires more investigation, however it appears that the cubosomes did not facilitate...

  18. In vitro drug release and percutaneous behavior of poloxamer-based hydrogel formulation containing traditional Chinese medicine.

    Science.gov (United States)

    Wang, Wenyi; Hui, Patrick C L; Wat, Elaine; Ng, Frency S F; Kan, Chi-Wai; Wang, Xiaowen; Wong, Eric C W; Hu, Huawen; Chan, Ben; Lau, Clara B S; Leung, Ping-Chung

    2016-12-01

    For the treatment of atopic dermatitis (AD), we have developed a transdermal functionalized textile therapy based on thermosensitive poloxamer 407 (P407) hydrogel containing a traditional Chinese herbal medicine. This study aims to investigate the effects of various formulation variables of P407/carboxymethyl cellulose sodium (P407/CMCs) composite hydrogel on the release of Cortex Moutan (CM) extract. Concentrations of P407 and CMCs showed significant influence on the release due to alteration of bulk viscosity of the system. An increase in pH values of release medium was found to appreciably impede the release of polar drug (CM) due to ionization. Elevated temperatures were also shown to facilitate the drug release. Moreover, the diffusional release behavior of CM from P407/CMCs composite hydrogel was found to follow the first-order kinetic model. Additionally, transdermal studies showed that permeability of the drug through the skin can be enhanced with addition of CMCs in the hydrogel formulation.

  19. Sol-Gel Synthesis and Antioxidant Properties of Yttrium Oxide Nanocrystallites Incorporating P-123

    OpenAIRE

    Rebeca Mellado-Vázquez; Margarita García-Hernández; Arturo López-Marure; Perla Yolanda López-Camacho; Ángel de Jesús Morales-Ramírez; Hiram Isaac Beltrán-Conde

    2014-01-01

    Yttrium oxide (Y2O3) nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems were heat-treated at temperatures from 700 °C to 900 °C. Systems at 900 °C were prepared in the presence and absence of P-123 using different molar ratios (P-123:Y = 1:1 and 2:1). Fourier transform infrared spectros...

  20. Incorporating significant amino acid pairs to identify O-linked glycosylation sites on transmembrane proteins and non-transmembrane proteins

    Directory of Open Access Journals (Sweden)

    Lee Tzong-Yi

    2010-10-01

    Full Text Available Abstract Background While occurring enzymatically in biological systems, O-linked glycosylation affects protein folding, localization and trafficking, protein solubility, antigenicity, biological activity, as well as cell-cell interactions on membrane proteins. Catalytic enzymes involve glycotransferases, sugar-transferring enzymes and glycosidases which trim specific monosaccharides from precursors to form intermediate structures. Due to the difficulty of experimental identification, several works have used computational methods to identify glycosylation sites. Results By investigating glycosylated sites that contain various motifs between Transmembrane (TM and non-Transmembrane (non-TM proteins, this work presents a novel method, GlycoRBF, that implements radial basis function (RBF networks with significant amino acid pairs (SAAPs for identifying O-linked glycosylated serine and threonine on TM proteins and non-TM proteins. Additionally, a membrane topology is considered for reducing the false positives on glycosylated TM proteins. Based on an evaluation using five-fold cross-validation, the consideration of a membrane topology can reduce 31.4% of the false positives when identifying O-linked glycosylation sites on TM proteins. Via an independent test, GlycoRBF outperforms previous O-linked glycosylation site prediction schemes. Conclusion A case study of Cyclic AMP-dependent transcription factor ATF-6 alpha was presented to demonstrate the effectiveness of GlycoRBF. Web-based GlycoRBF, which can be accessed at http://GlycoRBF.bioinfo.tw, can identify O-linked glycosylated serine and threonine effectively and efficiently. Moreover, the structural topology of Transmembrane (TM proteins with glycosylation sites is provided to users. The stand-alone version of GlycoRBF is also available for high throughput data analysis.

  1. SBA-15-incorporated nanoscale zero-valent iron particles for chromium(VI) removal from groundwater: mechanism, effect of pH, humic acid and sustained reactivity.

    Science.gov (United States)

    Sun, Xia; Yan, Yubo; Li, Jiansheng; Han, Weiqing; Wang, Lianjun

    2014-02-15

    Nanoscale zero-valent iron particles (NZVIs) were incorporated inside the channels of SBA-15 rods by a "two solvents" reduction technique and used to remove Cr(VI) from groundwater. The resulting NZVIs/SBA-15 composites before and after reaction were characterized by N2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Results helped to propose the mechanism of Cr(VI) removal by NZVIs/SBA-15, where Cr(VI) in aqueous was firstly impregnated into the channels of the silica, then adsorbed on the surfaces of the incorporated NZVIs and reduced to Cr(III) directly in the inner pores of the silica. Corrosion products included Fe2O3, FeO(OH), Fe3O4 and Cr2FeO4. Batch experiments revealed that Cr(VI) removal decreased from 99.7% to 92.8% when the initial solution pH increased from 5.5 to 9.0, accompanied by the decrease of the kobs from 0.600 to 0.024 min(-1). Humic acid (HA) had a little effect on the removal efficiency of Cr(VI) by NZVIs/SBA-15 but could decrease the reduction rate. The stable reduction of NZVIs/SBA-15 was observed within six cycles. NZVIs/SBA-15 composites offer a promising alternative material to remove heavy metals from groundwater.

  2. Manufacture and Incorporation of Liposome-Entrapped Ethylenediaminetetraacetic Acid into Model Miniature Gouda-Type Cheese and Subsequent Effect on Starter Viability, pH, and Moisture Content.

    Science.gov (United States)

    McAuliffe, Lisa N; Kilcawley, Kieran N; Sheehan, Jeremiah J; McSweeney, Paul L H

    2016-10-25

    Liposome-encapsulated ethylenediaminetetraacetic acid (EDTA) was incorporated into a model miniature Gouda-type cheese (20 g) in order to assess its effect on rennet gelation, starter viability, pH, and moisture content. EDTA was encapsulated within 2 different food-grade proliposome preparations, Pro-Lipo Duo and Pro-Lipo C (50% and 40% unsaturated soybean phospholipids and 50% and 60% aqueous medium, respectively), using the following high-shear technologies: Ultra-Turrax (5000 rpm), 2-stage homogenization (345 bar), or microfluidization (690 bar). Liposome size distribution was affected by the high-shear technology employed with the proportion of large vesicles (>100 nm) decreasing in the order microfluidization Gouda-type cheese. Addition of liposome-encapsulated EDTA to milk during cheese making did not impact pH or rennet gel formation. No differences in composition or pH were evident in liposome-treated cheeses. The results of this study show that the incorporation of liposome-encapsulated EDTA into milk during cheese manufacture did not affect milk fermentation, moisture content, or pH, suggesting that this approach may be suitable for studying the effects of calcium equilibrium on the texture of brine-salted cheeses. © 2016 Institute of Food Technologists®.

  3. A sustained release formulation of chitosan modified PLCL:poloxamer blend nanoparticles loaded with optical agent for animal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ranjan, Amalendu P; Zeglam, Karim; Mukerjee, Anindita; Vishwanatha, Jamboor K [Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States); Thamake, Sanjay, E-mail: Jamboor.vishwanatha@unthsc.edu [Department of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States)

    2011-07-22

    The objective of this study was to develop optical imaging agent loaded biodegradable nanoparticles with indocynanine green (ICG) using chitosan modified poly(L-lactide-co-epsilon-caprolactone) (PLCL):poloxamer (Pluronic F68) blended polymer. Nanoparticles were formulated with an emulsification solvent diffusion technique using PLCL and poloxamer as blend-polymers. Polyvinyl alcohol (PVA) and chitosan were used as stabilizers. The particle size, shape and zeta potential of the formulated nanoparticles and the release kinetics of ICG from these nanoparticles were determined. Further, biodistribution of these nanoparticles was studied in mice at various time points until 24 h following intravenous administration, using a non-invasive imaging system. The average particle size of the nanoparticles was found to be 146 {+-} 3.7 to 260 {+-} 4.5 nm. The zeta potential progressively increased from - 41.6 to + 25.3 mV with increasing amounts of chitosan. Particle size and shape of the nanoparticles were studied using transmission electron microscopy (TEM) which revealed the particles to be smooth and spherical in shape. These nanoparticles were efficiently delivered to the cytoplasm of the cells, as observed in prostate and breast cancer cells using confocal laser scanning microscopy. In vitro release studies indicated sustained release of ICG from the nanoparticles over a period of seven days. Nanoparticle distribution results in mice showing improved uptake and accumulation with chitosan modified nanoparticles in various organs and slower clearance at different time points over a 24 h period as compared to unmodified nanoparticles. The successful formulation of such cationically modified nanoparticles for encapsulating optical agents may lead to a potential deep tissue imaging technique for tumor detection, diagnosis and therapy.

  4. A sustained release formulation of chitosan modified PLCL:poloxamer blend nanoparticles loaded with optical agent for animal imaging

    Science.gov (United States)

    Ranjan, Amalendu P.; Zeglam, Karim; Mukerjee, Anindita; Thamake, Sanjay; Vishwanatha, Jamboor K.

    2011-07-01

    The objective of this study was to develop optical imaging agent loaded biodegradable nanoparticles with indocynanine green (ICG) using chitosan modified poly(L-lactide-co-epsilon-caprolactone) (PLCL):poloxamer (Pluronic F68) blended polymer. Nanoparticles were formulated with an emulsification solvent diffusion technique using PLCL and poloxamer as blend-polymers. Polyvinyl alcohol (PVA) and chitosan were used as stabilizers. The particle size, shape and zeta potential of the formulated nanoparticles and the release kinetics of ICG from these nanoparticles were determined. Further, biodistribution of these nanoparticles was studied in mice at various time points until 24 h following intravenous administration, using a non-invasive imaging system. The average particle size of the nanoparticles was found to be 146 ± 3.7 to 260 ± 4.5 nm. The zeta potential progressively increased from - 41.6 to + 25.3 mV with increasing amounts of chitosan. Particle size and shape of the nanoparticles were studied using transmission electron microscopy (TEM) which revealed the particles to be smooth and spherical in shape. These nanoparticles were efficiently delivered to the cytoplasm of the cells, as observed in prostate and breast cancer cells using confocal laser scanning microscopy. In vitro release studies indicated sustained release of ICG from the nanoparticles over a period of seven days. Nanoparticle distribution results in mice showing improved uptake and accumulation with chitosan modified nanoparticles in various organs and slower clearance at different time points over a 24 h period as compared to unmodified nanoparticles. The successful formulation of such cationically modified nanoparticles for encapsulating optical agents may lead to a potential deep tissue imaging technique for tumor detection, diagnosis and therapy.

  5. Pharmacokinetics and enhanced oral bioavailability in beagle dogs of cyclosporine A encapsulated in glyceryl monooleate/poloxamer 407 cubic nanoparticles

    Directory of Open Access Journals (Sweden)

    Jie Lai

    2009-12-01

    Full Text Available Jie Lai1,2, Yi Lu1, Zongning Yin2, Fuqiang Hu3, Wei Wu11School of Pharmacy, Fudan University, Shanghai, China, 2West China School of Pharmacy, Sichuan University, Chengdu, China, 3School of Pharmacy, Zhejiang University, Hangzhou, ChinaAbstract: Efforts to improve the oral bioavailability of cyclosporine A (CyA remains a challenge in the field of drug delivery. In this study, glyceryl monooleate (GMO/poloxamer 407 cubic nanoparticles were evaluated as potential vehicles to improve the oral bioavailability of CyA. Cubic nanoparticles were prepared via the fragmentation of a bulk GMO/poloxamer 407 cubic phase gel by sonication and homogenization. The cubic inner structure formed was verified using Cryo-TEM. The mean diameters of the nanoparticles were about 180 nm, and the entrapment efficiency of these particles for CyA was over 85%. The in vitro release of CyA from these nanoparticles was less than 5% at 12 h. The results of a pharmacokinetic study in beagle dogs showed improved absorption of CyA from cubic nanoparticles as compared to microemulsion-based Neoral®; higher Cmax (1371.18 ± 37.34 vs 969.68 ± 176.3 ng mL-1, higher AUC0–t (7757.21 ± 1093.64 vs 4739.52 ± 806.30 ng h mL-1 and AUC0–∞ (9004.77 ± 1090.38 vs 5462.31 ± 930.76 ng h mL-1. The relative oral bioavailability of CyA cubic nanoparticles calculated on the basis of AUC0–∞ was about 178% as compared to Neoral®. The enhanced bioavailability of CyA is likely due to facilitated absorption by cubic nanoparticles rather than improved release.Keywords: nanoparticles, cubosomes, cyclosporine A, glyceryl monooleate, oral drug delivery, bioavailability, beagle dogs

  6. Poloxamer 407-based intranasal thermoreversible gel of zolmitriptan-loaded nanoethosomes: formulation, optimization, evaluation and permeation studies.

    Science.gov (United States)

    Shelke, Santosh; Shahi, Sadhana; Jalalpure, Sunil; Dhamecha, Dinesh

    2016-12-01

    Zolmitriptan is the drug of choice for migraine, but low oral bioavailability (<50%) and recurrence of migraine lead to frequent dosing and increase in associated side effects. Increase in the residence time of drug at the site of drug absorption along with direct nose to brain targeting of zolmitriptan can be a solution to the existing problems. Hence, in the present investigation, thermoreversible intranasal gel of zolmitriptan-loaded nanoethosomes was formulated by using mucoadhesive polymers to increase the residence of the drug into the nasal cavity. The preparation of ethosomes was optimized by using 3(2) factorial design for percent drug entrapment efficiency, vesicle size, zeta potential, and polydispersity index. Optimized formulation E6 showed the vesicle size (171.67 nm) and entrapment efficiency (66%) when compared with the other formulations. Thermoreversible gels prepared by using poloxamer 407 showed the phase transition temperature at 32-33 °C which was in line with the nasal physiological temperature. The optimized ethosomes were loaded into the thermoreversible mucoadhesive gel optimized by varying concentrations of poloxamer 407, carbopol 934, HPMC K100, and evaluated for gel strength, gelation temperature, mucoadhesive strength, in vitro drug release, and ex vivo drug permeation, where G3 and G6 were found to be optimized formulations. In vitro drug release was studied by different kinetic models suggested that G3 (n = 0.582) and G6 (n = 0.648) showed Korsemeyer-Peppas (KKP) model indicating non-Fickian release profiles. A permeation coefficient of 5.92 and 5.9 µg/cm(2) for G3 and G6, respectively, revealed very little difference in release rate after 24 h between both the formulations. Non-toxic nature of the gels on columnar epithelial cells was confirmed by histopathological evaluation.

  7. Enhancing microdialysis recovery of metal ions by incorporating poly-L-aspartic acid and poly-L-histidine in the perfusion liquid

    Energy Technology Data Exchange (ETDEWEB)

    Mogopodi, Dikabo; Torto, Nelson

    2003-04-10

    A study of the evaluation of poly-L-aspartic acid and poly-L-histidine as binding agents to enhance microdialysis recovery of metal ions is presented. Investigations were carried out to compare microdialysis recovery for Cr, Cu, Ni, and Pb when using water as the perfusion liquid as well as when using various concentrations of poly-L-aspartic acid and poly-L-histidine in the perfusion liquid. All experiments were carried out under quiescent conditions using a concentric type of microdialysis probe fitted with a polysulfone membrane having a 30 kDa molecular weight cut-off and a 10 mm effective dialysis length. The metal ions were determined using an electrothermal atomic absorption spectrometer equipped with a Zeemann background corrector. Incorporation of 0.032% (w/v) of poly-L-aspartic acid enhanced the recovery of Cu and Pb by factors of 90 and 64%, respectively (%RSD<3). The recovery of Cr was enhanced by 5%, but that of Ni never exceeded values achieved using ultra pure water. The use of 20% (w/v) of poly-L-histidine resulted in enhancement factors of 66 and 4% for Cu and Pb, respectively (%RSD<2). For both Cr and Ni, the recovery never exceeded that achieved with water. The data from these studies demonstrate the suitability of poly-L-aspartic and poly-L-histidine as selective and effective binding agents that enhance the microdialysis recovery of metal ions. Application of the optimised conditions to the determination of Pb and Cu in a wastewater sample confirmed the versatility of microdialysis, as higher recoveries of Cu were obtained with poly-L-aspartic acid compared to direct determination.

  8. SBA-15-incorporated nanoscale zero-valent iron particles for chromium(VI) removal from groundwater: Mechanism, effect of pH, humic acid and sustained reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xia, E-mail: lygsunxia@163.com [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); School of Chemistry and Chemical Engineering, Huaihai Institute of Technology, Lianyungang 222005 (China); Yan, Yubo [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Li, Jiansheng, E-mail: lijsh@mail.njust.edu.cn [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Han, Weiqing [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Wang, Lianjun, E-mail: wanglj@mail.njust.edu.cn [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2014-02-15

    Highlights: • Zero-valent iron nanoparticles were incorporated in the pores of SBA-15 rods. • Mechanism of the Cr(VI) removal by NZVIs/SBA-15 was proposed. • A low pH value was in favor of the Cr(VI) removal. • Humic acid (HA) had a negligible effect on the reactivity of NZVIs/SBA-15. • The stable reduction of NZVIs/SBA-15 was observed within six cycles. -- Abstract: Nanoscale zero-valent iron particles (NZVIs) were incorporated inside the channels of SBA-15 rods by a “two solvents” reduction technique and used to remove Cr(VI) from groundwater. The resulting NZVIs/SBA-15 composites before and after reaction were characterized by N{sub 2} adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Results helped to propose the mechanism of Cr(VI) removal by NZVIs/SBA-15, where Cr(VI) in aqueous was firstly impregnated into the channels of the silica, then adsorbed on the surfaces of the incorporated NZVIs and reduced to Cr(III) directly in the inner pores of the silica. Corrosion products included Fe{sub 2}O{sub 3}, FeO(OH), Fe{sub 3}O{sub 4} and Cr{sub 2}FeO{sub 4}. Batch experiments revealed that Cr(VI) removal decreased from 99.7% to 92.8% when the initial solution pH increased from 5.5 to 9.0, accompanied by the decrease of the k{sub obs} from 0.600 to 0.024 min{sup −1}. Humic acid (HA) had a little effect on the removal efficiency of Cr(VI) by NZVIs/SBA-15 but could decrease the reduction rate. The stable reduction of NZVIs/SBA-15 was observed within six cycles. NZVIs/SBA-15 composites offer a promising alternative material to remove heavy metals from groundwater.

  9. Hair analysis for Delta9-tetrahydrocannabinolic acid A--new insights into the mechanism of drug incorporation of cannabinoids into hair.

    Science.gov (United States)

    Auwärter, Volker; Wohlfarth, Ariane; Traber, Jessica; Thieme, Detlef; Weinmann, Wolfgang

    2010-03-20

    Differentiation between external contamination and incorporation of drugs or their metabolites from inside the body via blood, sweat or sebum is a general issue in hair analysis and of high concern when interpreting analytical results. In hair analysis for cannabinoids the most common target is Delta9-tetrahydrocannabinol (THC), sometimes cannabidiol (CBD) and cannabinol (CBN) are determined additionally. After repeated external contamination by cannabis smoke these analytes are known to be found in hair even after performing multiple washing steps. A widely accepted strategy to unequivocally prove active cannabis consumption is the analysis of hair extracts for the oxidative metabolite 11-nor-9-carboxy-THC (THC-COOH). Although the acidic nature of this metabolite suggests a lower rate of incorporation into the hair matrix compared to THC, it is not fully understood up to now why hair concentrations of THC-COOH are generally found to be much lower (mostly <10 pg/mg) than the corresponding THC concentrations. Delta9-Tetrahydrocannabinolic acid A (THCA A) is the preliminary end product of the THC biosynthesis in the cannabis plant. Unlike THC it is non-psychoactive and can be regarded as a 'precursor' of THC being largely decarboxylated when heated or smoked. The presented work shows for the first time that THCA A is not only detectable in blood and urine of cannabis consumers but also in THC positive hair samples. A pilot experiment performed within this study showed that after oral intake of THCA A on a regular basis no relevant incorporation into hair occurred. It can be concluded that THCA A in hair almost exclusively derives from external contamination e.g. by side stream smoke. Elevated temperatures during the analytical procedure, particularly under alkaline conditions, can lead to decarboxylation of THCA A and accordingly increase THC concentrations in hair. Additionally, it has to be kept in mind that in hair samples tested positive for THCA A at least a

  10. Incorporation of sunflower oil or linseed oil in equine compound feedstuff: 1 Effects on haematology and on fatty acids profiles in the red blood cells membranes.

    Science.gov (United States)

    Patoux, S; Istasse, L

    2016-10-01

    Eight trained horses (6 mares - 2 geldings, 6 Selle Français, 2 Trotteur Français, 12 ± 5.8 years old, 538 ± 72.5 kg) were offered three diets to potentially affect haematology and the fatty acids (FA) profiles in red blood cells (RBC) membranes. The control diet was composed of 50% hay and 50% concentrate containing mainly rolled barley (48%) and whole spelt (48%). In the case of sunflower oil diet, sunflower oil (62.0% of α-linoleic acid, LA) was incorporated at a rate of 8% and substituted by an equal proportion of barley. In the linseed oil diet, first cold-pressed linseed oil (56.0% of α-linolenic acid, ALA) was utilised at a similar incorporation rate of 8%. The experimental design consisted of three 3 × 3 latin squares with one being incomplete. Each period lasted 8 weeks. On average, the total feed intake (straw excluded) was 6.2 kg/day and the oil intake 0.278 kg/day. The oils significantly increased the concentrations of RBC, haemoglobin and haematocrit. The oils had no significant impact on the haematology profiles except that platelets tended to decrease in both oil-based diets. The most abundant FA in the RBC membranes of the control diet samples were in the decreasing order LA, C18:1n9-7, C18:0, C16:0 and the arachidonic acid (ARA) respectively. The sunflower oil supplementation slightly increased the amount of LA (36.23 vs. 34.72 mg/dl, p = 0.55) and C22:4n-6 (0.21 vs. 0.09 mg/dl, p = 0.22), while the decrease was observed in case of other FA (C16:1n-7, 1.08 vs. 1.42 mg/dl, p = 0.03), C20:3n-6 (0.22 vs. 0.31 mg/dl, p = 0.02), and ARA (1.17 vs. 1.63 mg/dl, p = 0.08). Linseed oil induced similar effects in the n-6 series FA profiles. In the context of practical applications, our results show that linseed oil incorporation in the diet could improve the haematology and the n-3 FA profiles potentially leading to an increased performance. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  11. Molecular and structural basis of inner core lipopolysaccharide alterations in Escherichia coli: incorporation of glucuronic acid and phosphoethanolamine in the heptose region.

    Science.gov (United States)

    Klein, Gracjana; Müller-Loennies, Sven; Lindner, Buko; Kobylak, Natalia; Brade, Helmut; Raina, Satish

    2013-03-22

    It is well established that lipopolysaccharide (LPS) often carries nonstoichiometric substitutions in lipid A and in the inner core. In this work, the molecular basis of inner core alterations and their physiological significance are addressed. A new inner core modification of LPS is described, which arises due to the addition of glucuronic acid on the third heptose with a concomitant loss of phosphate on the second heptose. This was shown by chemical and structural analyses. Furthermore, the gene whose product is responsible for the addition of this sugar was identified in all Escherichia coli core types and in Salmonella and was designated waaH. Its deduced amino acid sequence exhibits homology to glycosyltransferase family 2. The transcription of the waaH gene is positively regulated by the PhoB/R two-component system in a growth phase-dependent manner, which is coordinated with the transcription of the ugd gene explaining the genetic basis of this modification. Glucuronic acid modification was observed in E. coli B, K12, R2, and R4 core types and in Salmonella. We also show that the phosphoethanolamine (P-EtN) addition on heptose I in E. coli K12 requires the product of the ORF yijP, a new gene designated as eptC. Incorporation of P-EtN is also positively regulated by PhoB/R, although it can occur at a basal level without a requirement for any regulatory inducible systems. This P-EtN modification is essential for resistance to a variety of factors, which destabilize the outer membrane like the addition of SDS or challenge to sublethal concentrations of Zn(2+).

  12. D-Amino acids incorporation in the frog skin-derived peptide esculentin-1a(1-21)NH2 is beneficial for its multiple functions.

    Science.gov (United States)

    Di Grazia, Antonio; Cappiello, Floriana; Cohen, Hadar; Casciaro, Bruno; Luca, Vincenzo; Pini, Alessandro; Di, Y Peter; Shai, Yechiel; Mangoni, Maria Luisa

    2015-12-01

    Naturally occurring antimicrobial peptides (AMPs) represent promising future antibiotics. We have previously isolated esculentin-1a(1-21)NH2, a short peptide derived from the frog skin AMP esculentin-1a, with a potent anti-Pseudomonal activity. Here, we investigated additional functions of the peptide and properties responsible for these activities. For that purpose, we synthesized the peptide, as well as its structurally altered analog containing two D-amino acids. The peptides were then biophysically and biologically investigated for their cytotoxicity and immunomodulating activities. The data revealed that compared to the wild-type, the diastereomer: (1) is significantly less toxic towards mammalian cells, in agreement with its lower α-helical structure, as determined by circular dichroism spectroscopy; (2) is more effective against the biofilm form of Pseudomonas aeruginosa (responsible for lung infections in cystic fibrosis sufferers), while maintaining a high activity against the free-living form of this important pathogen; (3) is more stable in serum; (4) has a higher activity in promoting migration of lung epithelial cells, and presumably in healing damaged lung tissue, and (5) disaggregates and detoxifies the bacterial lipopolysaccharide (LPS), albeit less than the wild-type. Light scattering studies revealed a correlation between anti-LPS activity and the ability to disaggregate the LPS. Besides shedding light on the multifunction properties of esculentin-1a(1-21)NH2, the D-amino acid containing isomer may serve as an attractive template for the development of new anti-Pseudomonal compounds with additional beneficial properties. Furthermore, together with other studies, incorporation of D-amino acids may serve as a general approach to optimize the future design of new AMPs.

  13. An attempt to stabilize tanshinone IIA solid dispersion by the use of ternary systems with nano-CaCO 3 and poloxamer 188

    Directory of Open Access Journals (Sweden)

    Hong-mei Yan

    2014-01-01

    Full Text Available Background: Tanshinone IIA (TSIIA on solid dispersions (SDs has thermodynamical instability of amorphous drug. Ternary solid dispersions (tSDs can extend the stability of the amorphous form of drug. Poloxamer 188 was used as a SD carrier. Nano-CaCO 3 played an important role in adsorption of biomolecules and is being developed for a host of biotechnological applications. Objective: The aim of the present study was to investigate the dissolution behavior and accelerated stability of TSIIA on solid dispersions (SDs by the use of ternary systems with nano-CaCO 3 and poloxamer 188. Materials and Methods: The TSIIA tSDs were prepared by a spray-drying method. First, the effect of combination of poloxamer 188 and nano-CaCO 3 on TSIIA dissolution was studied. Subsequently, a set of complementary techniques (DSC, XRPD, SEM and FTIR was used to monitor the physical changes of TSIIA in the SDs. Finally, stability test was carried out under the conditions 40°C/75% RH for 6 months. Results: The characterization of tSDs by differential scanning calorimetry analysis (DSC and X-ray powder diffraction (XRPD showed that TSIIA was present in its amorphous form. Fourier transforms infrared spectroscopy (FTIR suggested the presence of interactions between TSIIA and carriers in tSDs. Improvement in the dissolution rate was observed for all SDs. The stability study conducted on SDs with nano-CaCO 3 showed stable drug content and dissolution behavior, over the period of 6 months as compared with freshly prepared SDs. Conclusion: SDs preparation with nano-CaCO 3 and poloxamer 188 may be a promising approach to enhance the dissolution and stability of TSIIA.

  14. Synergistic effect of pH-responsive folate-functionalized poloxamer 407-TPGS-mixed micelles on targeted delivery of anticancer drugs

    Directory of Open Access Journals (Sweden)

    Butt AM

    2015-02-01

    Full Text Available Adeel Masood Butt, Mohd Cairul Iqbal Mohd Amin, Haliza Katas Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia Background: Doxorubicin (DOX, an anthracycline anticancer antibiotic, is used for treating various types of cancers. However, its use is associated with toxicity to normal cells and development of resistance due to overexpression of drug efflux pumps. Poloxamer 407 (P407 and vitamin E TPGS (d-α-tocopheryl polyethylene glycol succinate, TPGS are widely used polymers as drug delivery carriers and excipients for enhancing the drug retention times and stability. TPGS reduces multidrug resistance, induces apoptosis, and shows selective anticancer activity against tumor cells. Keeping in view the problems, we designed a mixed micelle system encapsulating DOX comprising TPGS for its selective anticancer activity and P407 conjugated with folic acid (FA for folate-mediated receptor targeting to cancer cells. Methods: FA-functionalized P407 was prepared by carbodiimide crosslinker chemistry. P407-TPGS/FA-P407-TPGS-mixed micelles were prepared by thin-film hydration method. Cytotoxicity of blank micelles, DOX, and DOX-loaded micelles was determined by alamarBlue® assay. Results: The size of micelles was less than 200 nm with encapsulation efficiency of 85% and 73% for P407-TPGS and FA-P407-TPGS micelles, respectively. Intracellular trafficking study using nile red-loaded micelles indicated improved drug uptake and perinuclear drug localization. The micelles show minimal toxicity to normal human cell line WRL-68, enhanced cellular uptake of DOX, reduced drug efflux, increased DOX–DNA binding in SKOV3 and DOX-resistant SKOV3 human ovarian carcinoma cell lines, and enhanced in vitro cytotoxicity as compared to free DOX. Conclusion: FA-P407-TPGS-DOX micelles show potential as a targeted nano-drug delivery system for DOX due to their multiple synergistic factors of selective anticancer

  15. iHyd-PseAAC: Predicting Hydroxyproline and Hydroxylysine in Proteins by Incorporating Dipeptide Position-Specific Propensity into Pseudo Amino Acid Composition

    Directory of Open Access Journals (Sweden)

    Yan Xu

    2014-05-01

    Full Text Available Post-translational modifications (PTMs play crucial roles in various cell functions and biological processes. Protein hydroxylation is one type of PTM that usually occurs at the sites of proline and lysine. Given an uncharacterized protein sequence, which site of its Pro (or Lys can be hydroxylated and which site cannot? This is a challenging problem, not only for in-depth understanding of the hydroxylation mechanism, but also for drug development, because protein hydroxylation is closely relevant to major diseases, such as stomach and lung cancers. With the avalanche of protein sequences generated in the post-genomic age, it is highly desired to develop computational methods to address this problem. In view of this, a new predictor called “iHyd-PseAAC” (identify hydroxylation by pseudo amino acid composition was proposed by incorporating the dipeptide position-specific propensity into the general form of pseudo amino acid composition. It was demonstrated by rigorous cross-validation tests on stringent benchmark datasets that the new predictor is quite promising and may become a useful high throughput tool in this area. A user-friendly web-server for iHyd-PseAAC is accessible at http://app.aporc.org/iHyd-PseAAC/. Furthermore, for the convenience of the majority of experimental scientists, a step-by-step guide on how to use the web-server is given. Users can easily obtain their desired results by following these steps without the need of understanding the complicated mathematical equations presented in this paper just for its integrity.

  16. Optimisation of a system for the co-translational incorporation of a keto amino acid and its application to a tumour-specific Anticalin.

    Science.gov (United States)

    Reichert, Andreas J; Poxleitner, Gabriele; Dauner, Martin; Skerra, Arne

    2015-12-01

    The bioorthogonal keto group has attracted interest for the site-specific chemical conjugation of recombinant proteins under mild conditions, e.g. with aminooxy-functionalised fluorescent probes, radiometal chelates, toxins or polymers. However, the cotranslational incorporation of the corresponding non-canonical amino acid p-acetyl-L-phenylalanine (Apa) into proteins expressed in Escherichia coli by means of amber suppression using a previously described system with a mutated tRNA and an engineered tyrosyl-tRNA synthetase from Methanococcus jannaschii shows limited efficiency and considerable promiscuity towards endogenous amino acids. Employing a one-plasmid system that encodes all three components required for selection, i.e. the modified aminoacyl-tRNA synthetase (aaRS), the cognate amber suppressor tRNA and the enhanced green fluorescent protein equipped with an amber stop codon and serving as reporter, we have generated an Apa-specific aaRS&tRNA pair with considerably improved efficiency (17-fold increased expression) and also fidelity (6-fold). To this end, both the aaRS and the tRNA were subjected to doped random mutagenesis and selection in altogether four evolutionary cycles using fluorescence-activated bacterial cell sorting as well as automated screening of microcultures. The resulting aaRS&tRNA pair was applied to the functionalisation of an Anticalin with specificity towards oncofetal fibronectin by introducing a keto group at a permissible site for subsequent conjugation with a fluorescent dye, thus allowing visualisation of this tumour target under the microscope.

  17. Organic acids and protein compounds causing the photoluminescence properties of natural rubber membranes and the quenching phenomena from Au nanoparticle incorporation.

    Science.gov (United States)

    Cabrera, Flávio C; Agostini, Deuber L S; Dos Santos, Renivaldo J; Guimarães, Francisco E G; Guerrero, Ariel R; Aroca, Ricardo F; Job, Aldo E

    2014-12-01

    Natural rubber membranes were fabricated using latex from Hevea brasiliensis trees (clone RRIM 600) by casting, and controlling the time and temperature of thermal treatment. Three temperatures were used: 65, 80 and 120 °C and the corresponding annealing times of 6, 8, 10 and 12 h. The centrifugation of the latex produces the constituent phases: solid rubber (F1), serum or protein components (F2) and bottom fraction (F3). The photoluminescence properties could be correlated with organic acid components of latex. Natural rubber membranes were used as the active substrate (reducing agent) for the incorporation of colloidal Au nanoparticles synthesized by in situ reduction at different times. The intensity of photoluminescence bands assigned to the natural rubber decreases with the increase in amount of nanoparticles present on the membrane surface. It can be assumed that Au nanoparticles may be formed by reduction of the Au cation reacting with functional groups that are directly related to photoluminescence properties. However, the quenching of fluorescence may be attributed to the formation of a large amount of metal nanostructures on the natural rubber surface. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Drug-eluting coating of ginsenoside Rg1 and Re incorporated poly(lactic-co-glycolic acid) on stainless steel 316L: Physicochemical and drug release analyses.

    Science.gov (United States)

    Miswan, Zulaika; Lukman, Siti Khadijah; Abd Majid, Fadzilah Adibah; Loke, Mun Fai; Saidin, Syafiqah; Hermawan, Hendra

    2016-12-30

    Active ingredients of ginsenoside, Rg1 and Re, are able to inhibit the proliferation of vascular smooth muscle cells and promote the growth of vascular endothelial cells. These capabilities are of interest for developing a novel drug-eluting stent to potentially solve the current problem of late-stent thrombosis and poor endotheliazation. Therefore, this study was aimed to incorporate ginsenoside into degradable coating of poly(lactic-co-glycolic acid) (PLGA). Drug mixture composed of ginseng extract and 10% to 50% of PLGA (xPLGA/g) was coated on electropolished stainless steel 316L substrate by using a dip coating technique. The coating was characterized principally by using attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscopy and contact angle analysis, while the drug release profile of ginsenosides Rg1 and Re was determined by using mass spectrometry at a one month immersion period. Full and homogenous coating coverage with acceptable wettability was found on the 30PLGA/g specimen. All specimens underwent initial burst release dependent on their composition. The 30PLGA/g and 50PLGA/g specimens demonstrated a controlled drug release profile having a combination of diffusion- and swelling-controlled mechanisms of PLGA. The study suggests that the 30PLGA/g coated specimen expresses an optimum composition which is seen as practicable for developing a controlled release drug-eluting stent.

  19. Glial Fibrillary Acidic Protein Filaments Can Tolerate the Incorporation of Assembly-compromised GFAP-δ, but with Consequences for Filament Organization and αB-Crystallin Association

    Science.gov (United States)

    Perng, Ming-Der; Wen, Shu-Fang; Gibbon, Terry; Middeldorp, Jinte; Sluijs, Jacqueline; Hol, Elly M.

    2008-01-01

    The glial fibrillary acidic protein (GFAP) gene is alternatively spliced to give GFAP-α, the most abundant isoform, and seven other differentially expressed transcripts including GFAP-δ. GFAP-δ has an altered C-terminal domain that renders it incapable of self-assembly in vitro. When titrated with GFAP-α, assembly was restored providing GFAP-δ levels were kept low (∼10%). In a range of immortalized and transformed astrocyte derived cell lines and human spinal cord, we show that GFAP-δ is naturally part of the endogenous intermediate filaments, although levels were low (∼10%). This suggests that GFAP filaments can naturally accommodate a small proportion of assembly-compromised partners. Indeed, two other assembly-compromised GFAP constructs, namely enhanced green fluorescent protein (eGFP)-tagged GFAP and the Alexander disease–causing GFAP mutant, R416W GFAP both showed similar in vitro assembly characteristics to GFAP-δ and could also be incorporated into endogenous filament networks in transfected cells, providing expression levels were kept low. Another common feature was the increased association of αB-crystallin with the intermediate filament fraction of transfected cells. These studies suggest that the major physiological role of the assembly-compromised GFAP-δ splice variant is as a modulator of the GFAP filament surface, effecting changes in both protein– and filament–filament associations as well as Jnk phosphorylation. PMID:18685083

  20. Exogenous incorporation of neugc-rich mucin augments n-glycolyl sialic acid content and promotes malignant phenotype in mouse tumor cell lines

    Directory of Open Access Journals (Sweden)

    Alonso Daniel F

    2009-12-01

    Full Text Available Abstract Background Carbohydrates embedded in the plasma membrane are one of the main actors involved in the communication of cells with the microenvironment. Neuraminic sialic acids are glycocalyx sugars that play important roles in the modulation of malignant cell behaviour. N-glycolylneuraminic acid (NeuGc is synthesized by the cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH, an enzyme expressed in all mammals except humans. In mice, this sugar is synthesized in several somatic tissues. Methods We used the B16 melanoma and F3II mammary carcinoma mouse tumor cell lines. By CMAH directed RT-PCR and NeuGc detection with the specific anti-NeuGc-GM3 antibody 14F7 we evaluated enzyme and ganglioside expression in tumor cells, respectively. Expression of NeuGc-GM3 ganglioside was reached by in vitro incubation with NeuGc-rich bovine submaxillary mucin and evaluated by slot-blot and immunohistochemistry assays using the 14F7 antibody. Tumor cells treated with mucin or purified NeuGc were injected s.c. and i.v. in syngeneic mice to evaluate tumor and metastatic growth. Results In the present work we demonstrated the absence of expression of CMAH enzyme in B16 melanoma and F3II mammary carcinoma cells. In vitro incubation of these NeuGc-negative cells with NeuGc-rich mucin increased the presence of NeuGc in cell membranes for at least 48-72 h, as a component of the GM3 ganglioside. Preincubation with NeuGc-rich mucin reduced tumor latency and increased the metastatic potential of tumor cells in syngeneic animals. Similar results were obtained when cells were incubated with purified NeuGc alone. Conclusion Our results indicate that B16 and F3II mouse tumor cell lines do not express NeuGc in cell membranes but they are able to incorporate NeuGc from an exogenous source, contributing to the malignant phenotype of melanoma and mammary carcinoma cells.

  1. Incorporation of Human-Platelet-Derived Growth Factor-BB Encapsulated Poly(lactic-co-glycolic acid) Microspheres into 3D CORAGRAF Enhances Osteogenic Differentiation of Mesenchymal Stromal Cells

    DEFF Research Database (Denmark)

    Mohan, Saktiswaren; Raghavendran, Hanumantharao Balaji; Karunanithi, Puvanan

    2017-01-01

    of growth factors has been demonstrated to produce severe side effects on the surrounding tissues. In this study, poly(lactic-co-glycolic acid) (PLGA) microspheres (MS) incorporated three-dimensional (3D) CORAGRAF scaffolds were engineered to achieve controlled release of platelet-derived growth factor...

  2. Hypolipidemic Effects of Aqueous Extract of Three Cultivars of Musa sapientum Fruit Peel on Poloxamer-407 Induced Hyperlipidemic Wistar Rats.

    Directory of Open Access Journals (Sweden)

    C EDENTA

    2014-12-01

    Full Text Available Objective: The effect of aqueous extracts of the ripped fruit peel of three cultivars of Musa sapientum (Saro, Ominni and Oranta on the lipid profile of normolipidemic and hyperlipidemic rats were examined. Methods: Aqueous peel extracts of the 3-cultivars of Musa sapientum (100mg/Kg bw were administered to normolipidemic and poloxamer-407 induced hyperlidemic rats (140-180g. Atorvastatin was used as standard drug (70 mg/Kg bw. Blood samples were collected for determination of plasma total cholesterol (Tc, triacylglycerides (TAG, low-density lipoprotein cholesterol (LDL-c and high-density lipoprotein cholesterol (HDL-c after 21-days in normolipidemic rats and 3-days in hyperlipidemic rats. Results: Normolipidemic rats treated with extract of Saro showed a significant (p0.05 difference when compared to the Atorvastatin and normal control groups. Conclusion: The findings in this study reveals Oranta cultivar of M. sapientum as a better potential drug candidate among the cultivars studied, hence could be useful for the treatment of hyperlipidemia and other cardiovascular related diseases.

  3. Poloxamer 188 protects neurons against ischemia/reperfusion injury through preserving integrity of cell membranes and blood brain barrier.

    Directory of Open Access Journals (Sweden)

    Jin-Hua Gu

    Full Text Available Poloxamer 188 (P188, a multiblock copolymer surfactant, has been shown to protect against ischemic tissue injury of cardiac muscle, testes and skeletal muscle, but the mechanisms have not been fully understood. In this study, we explored whether P188 had a protective effect against cerebral ischemia/reperfusion injury and its underlying mechanisms. The in vivo results showed that P188 significantly reduced the infarct volume, ameliorated the brain edema and neurological symptoms 24 h after ischemia/reperfusion. In the long-term outcome study, P188 markedly alleviated brain atrophy and motor impairments and increased survival rate in 3 weeks of post stroke period. Additionally, P188 protected cultured hippucampal HT22 cells against oxygen-glucose deprivation and reoxygenation (OGD/R injury. The ability in membrane sealing was assessed with two fluorescent membrane-impermeant dyes. The results showed that P188 treatment significantly reduced the PI-positive cells following ischemia/reperfusion injury and repaired the HT22 cell membrane rupture induced by Triton X-100. In addition, P188 inhibited ischemia/reperfusion-induced activation of matrix metalloproteinase (MMP-9 and leakage of Evans blue. Therefore, the present study concludes that P188 can protect against cerebral ischemia/reperfusion injury, and the protection involves multi-mechanisms in addition to the membrane resealing.

  4. Dual-functional transdermal drug delivery system with controllable drug loading based on thermosensitive poloxamer hydrogel for atopic dermatitis treatment

    Science.gov (United States)

    Wang, Wenyi; Wat, Elaine; Hui, Patrick C. L.; Chan, Ben; Ng, Frency S. F.; Kan, Chi-Wai; Wang, Xiaowen; Hu, Huawen; Wong, Eric C. W.; Lau, Clara B. S.; Leung, Ping-Chung

    2016-04-01

    The treatment of atopic dermatitis (AD) has long been viewed as a problematic issue by the medical profession. Although a wide variety of complementary therapies have been introduced, they fail to combine the skin moisturizing and drug supply for AD patients. This study reports the development of a thermo-sensitive Poloxamer 407/Carboxymethyl cellulose sodium (P407/CMCs) composite hydrogel formulation with twin functions of moisture and drug supply for AD treatment. It was found that the presence of CMCs can appreciably improve the physical properties of P407 hydrogel, which makes it more suitable for tailored drug loading. The fabricated P407/CMCs composite hydrogel was also characterized in terms of surface morphology by field emission scanning electron microscopy (FE-SEM), rheological properties by a rheometer, release profile in vitro by dialysis method and cytotoxicity test. More importantly, the findings from transdermal drug delivery behavior revealed that P407/CMCs showed desirable percutaneous performance. Additionally, analysis of cytotoxicity test suggested that P407/CMCs composite hydrogel is a high-security therapy for clinical trials and thus exhibits a promising way to treat AD with skin moisturizing and medication.

  5. Self-assembled silk sericin/poloxamer nanoparticles as nanocarriers of hydrophobic and hydrophilic drugs for targeted delivery

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Biman B; Kundu, S C, E-mail: kundu@hijli.iitkgp.ernet.i [Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302 (India)

    2009-09-02

    In recent times self-assembled micellar nanoparticles have been successfully employed in tissue engineering for targeted drug delivery applications. In this review, silk sericin protein from non-mulberry Antheraea mylitta tropical tasar silk cocoons was blended with pluronic F-127 and F-87 in the presence of solvents to achieve self-assembled micellar nanostructures capable of carrying both hydrophilic (FITC-inulin) and hydrophobic (anticancer drug paclitaxel) drugs. The fabricated nanoparticles were subsequently characterized for their size distribution, drug loading capability, cellular uptake and cytotoxicity. Nanoparticle sizes ranged between 100 and 110 nm in diameter as confirmed by dynamic light scattering. Rapid uptake of these particles into cells was observed in in vitro cellular uptake studies using breast cancer MCF-7 cells. In vitro cytotoxicity assay using paclitaxel-loaded nanoparticles against breast cancer cells showed promising results comparable to free paclitaxel drugs. Drug-encapsulated nanoparticle-induced apoptosis in MCF-7 cells was confirmed by FACS and confocal microscopic studies using Annexin V staining. Up-regulation of pro-apoptotic protein Bax, down-regulation of anti-apoptotic protein Bcl-2 and cleavage of regulatory protein PARP through Western blot analysis suggested further drug-induced apoptosis in cells. This study projects silk sericin protein as an alternative natural biomaterial for fabrication of self-assembled nanoparticles in the presence of poloxamer for successful delivery of both hydrophobic and hydrophilic drugs to target sites.

  6. Design of carrier tRNAs and selection of four-base codons for efficient incorporation of various nonnatural amino acids into proteins in Spodoptera frugiperda 21 (Sf21) insect cell-free translation system.

    Science.gov (United States)

    Taki, Masumi; Tokuda, Yasunori; Ohtsuki, Takashi; Sisido, Masahiko

    2006-12-01

    Spodoptera frugiperda 21 (Sf21) insect cell-free protein synthesizing system was expanded to include nonnatural amino acids. Orthogonal tRNAs that work as carriers of nonnatural amino acids in the insect system were explored. Four-base codons for assigning the positions of nonnatural amino acids were also selected. Mutated streptavidin mRNAs that contained different four-base codons were prepared and added to the insect cell-free system in the presence of various tRNAs possessing the corresponding four-base anticodons. The tRNAs were chemically aminoacylated with various types of nonnatural amino acids to examine their incorporation efficiencies. Using p-nitrophenylalanine as the nonnatural amino acid and streptavidin as the target protein, tRNA sequences and the types of four-base codons were optimized to maximize the yield of the nonnatural mutant and to minimize production of full-length proteins that do not contain the nonnatural amino acid. Among the tRNA sequences taken from a variety of tRNAs of nonstandard structures, the tRNA derived from Methanosarcina acetivorans tRNA(Pyl) was the most efficient and orthogonal tRNA. Of the CGGN-type four-base codons, CGGA and CGGG were the most efficient ones for assigning the positions of nonnatural amino acids. p-Nitrophenylalanine and 2-naphthylalanine were efficiently incorporated as in the case of Escherichia coli and rabbit reticulocyte cell-free systems. Much less efficient incorporation was observed, however, for other nonnatural amino acids, indicating that the insect system is less tolerant to the structural diversity of amino acids than the E. coli cell-free system.

  7. Preparation and evaluation of 17-allyamino-17-demethoxygeldanamycin (17-AAG)-loaded poly(lactic acid-co-glycolic acid) nanoparticles.

    Science.gov (United States)

    Pradhan, Roshan; Poudel, Bijay Kumar; Choi, Ju Yeon; Choi, Im Soon; Shin, Beom Soo; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

    2015-01-01

    In the present study, we developed the novel 17-allyamino-17-demethoxygeldanamycin (17-AAG)-loaded poly(lactic acid-co-glycolic acid) (PLGA) nanoparticles (NPs) using the combination of sodium lauryl sulfate and poloxamer 407 as the anionic and non-ionic surfactant for stabilization. The PLGA NPs were prepared by emulsification/solvent evaporation method. Both the drug/polymer ratio and phase ratio were 1:10 (w/w). The optimized formulation of 17-AAG-loaded PLGA NPs had a particle size and polydispersity index of 151.6 ± 2.0 and 0.152 ± 0.010 nm, respectively, which was further supported by TEM image. The encapsulation efficiency and drug loading capacity were 69.9 and 7.0%, respectively. In vitro release study showed sustained release. When in vitro release data were fitted to Korsmeyer-Peppas model, the n value was 0.468, which suggested that the drug was released by anomalous or non-Fickian diffusion. In addition, 17-AAG-loaded PLGA NPs in 72 h, displayed approximately 60% cell viability reduction at 10 µg/ml 17-AAG concentration, in MCF-7 cell lines, indicating sustained release from NPs. Therefore, our results demonstrated that incorporation of 17-AAG into PLGA NPs could provide a novel effective nanocarrier for the treatment of cancer.

  8. Human risk of diseases associated with red meat intake: Analysis of current theories and proposed role for metabolic incorporation of a non-human sialic acid.

    Science.gov (United States)

    Alisson-Silva, Frederico; Kawanishi, Kunio; Varki, Ajit

    2016-10-01

    One of the most consistent epidemiological associations between diet and human disease risk is the impact of red meat consumption (beef, pork, and lamb, particularly in processed forms). While risk estimates vary, associations are reported with all-cause mortality, colorectal and other carcinomas, atherosclerotic cardiovascular disease, type II diabetes, and possibly other inflammatory processes. There are many proposed explanations for these associations, some long discussed in the literature. Attempts to explain the effects of red meat consumption have invoked various red meat-associated agents, including saturated fat, high salt intake, Trimethylamine-N-oxide (TMAO) generation by microbiota, and environmental pollutants contaminating red meat, none of which are specific for red meat. Even the frequently mentioned polycyclic aromatic carcinogens arising from high temperature cooking methods are not red meat specific, as these are also generated by grilling poultry or fish, as well as by other forms of cooking. The traditional explanations that appear to be more red meat specific invoke the impact of N-nitroso compounds, heme iron, and the potential of heme to catalyze endogenous nitrosation. However, heme can be denatured by cooking, high levels of plasma hemopexin will block its tissue delivery, and much higher amounts of heme likely originate from red blood cell breakdown in vivo. Therefore, red meat-derived heme could only contribute to colorectal carcinoma risk, via direct local effects. Also, none of these mechanisms explain the apparent human propensity i.e., other carnivores have not been reported at high risk for all these diseases. A more recently proposed hypothesis involves infectious agents in beef from specific dairy cattle as agents of colorectal cancer. We have also described another mechanistic explanation for the human propensity for risk of red-meat associated diseases that is consistent with most observations: metabolic incorporation of a non

  9. Brain docosahexaenoic acid [DHA] incorporation and blood flow are increased in chronic alcoholics: a positron emission tomography study corrected for cerebral atrophy.

    Directory of Open Access Journals (Sweden)

    John C Umhau

    Full Text Available OBJECTIVE: Chronic alcohol dependence has been associated with disturbed behavior, cerebral atrophy and a low plasma concentration of docosahexaenoic acid (DHA, 22∶6n-3, particularly if liver disease is present. In animal models, excessive alcohol consumption is reported to reduce brain DHA concentration, suggesting disturbed brain DHA metabolism. We hypothesized that brain DHA metabolism also is abnormal in chronic alcoholics. METHODS: We compared 15 non-smoking chronic alcoholics, studied within 7 days of their last drink, with 22 non-smoking healthy controls. Using published neuroimaging methods with positron emission tomography (PET, we measured regional coefficients (K* and rates (J(in of DHA incorporation from plasma into the brain of each group using [1-(11C]DHA, and regional cerebral blood flow (rCBF using [(15O]water. Data were partial volume error corrected for brain atrophy. Plasma unesterified DHA concentration also was quantified. RESULTS: Mean K* for DHA was significantly and widely elevated by 10-20%, and rCBF was elevated by 7%-34%, in alcoholics compared with controls. Unesterified plasma DHA did not differ significantly between groups nor did whole brain J(in, the product of K* and unesterified plasma DHA concentration. DISCUSSION: Significantly higher values of K* for DHA in alcoholics indicate increased brain avidity for DHA, thus a brain DHA metabolic deficit vis-à-vis plasma DHA availability. Higher rCBF in alcoholics suggests increased energy consumption. These changes may reflect a hypermetabolic state related to early alcohol withdrawal, or a general brain metabolic change in chronic alcoholics.

  10. Stabilization of parallel triplexes by twisted intercalating nucleic acids (TINAs) incorporating 1,2,3-triazole units and prepared by microwave-accelerated click chemistry.

    Science.gov (United States)

    Géci, Imrich; Filichev, Vyacheslav V; Pedersen, Erik B

    2007-01-01

    A highly efficient method for postsynthetic modification of unprotected oligonucleotides incorporating internal insertions of (R)-1-O-(4-ethynylbenzyl)glycerol has been developed through the application of click chemistry with water-insoluble pyren-1-yl azide and water-soluble benzyl azide and acceleration by microwave irradiation. The twisted intercalating nucleic acids (TINAs) obtained in these reactions, possessing bulged insertions of (R)-3-O-{4-[1-(pyren-1-yl)-1H-1,2,3-triazol-4-yl]benzyl}glycerol (7), formed parallel triplexes with thermal stabilities of 20.0, 34.0, and 40.0 degrees C at pH 7.2 in the cases of one, two, or three insertions of 7, respectively, separated by three nucleic bases. An oligonucleotide with four insertions of 7--each between three nucleic bases in the sequence--was unable to form complexes with complementary single- or double-stranded DNAs, as a result of self-aggregation of the pyrene moieties. This assumption was supported by the formation of a very strong excimer band at 460 nm in the fluorescence spectra. Molecular modeling of the parallel triplex with bulged insertion of the monomer 7 in the triplex-forming oligonucleotide (TFO) showed that only the pyrene moiety was stacking between the bases of the dsDNA, whereas 1,2,3-triazole did not participate in the triplex stabilization. Thermal denaturation studies of the duplexes and triplexes, as well as the fluorescence properties of TINA-triazole 7, are discussed and compared with previous studies on TINA.

  11. Nisin Incorporated With 2,3-Dihydroxybenzoic Acid in Nanofibers Inhibits Biofilm Formation by a Methicillin-Resistant Strain of Staphylococcus aureus.

    Science.gov (United States)

    Ahire, Jayesh J; Dicks, Leon M T

    2015-03-01

    The aim of the present study was to determine the effect of nisin, 2,3-dihydroxybenzoic acid (DHBA) and a combination of nisin and DHBA incorporated into nanofibers prepared from poly(D,L-lactide) (PDLLA) and poly(ethylene oxide) (PEO) on biofilm formation of a methicillin-resistant strain of Staphylococcus aureus (strain Xen 31). Biofilm formation decreased by 88% after 24 h of exposure to nanofibers containing nisin and DHBA (NDF), compared to a 63% decrease when exposed to nanofibers containing only DHBA (DF) and a 3% decrease when exposed to nanofibers containing only nisin (NF). Planktonic cell numbers of biofilms exposed to nanofibers without nisin or DHBA (CF) and NF increased from no detectable OD(595nm) readings to 0.35 and 0.3, respectively, within the first 8 h of exposure, followed by a steady decline over the following 16 h. Planktonic cells of biofilms treated with DF increased from no detectable OD(595nm) readings to 0.05 after 8 h of exposure and remained more-or-less constant for the duration of the experiment. Planktonic cells of biofilms exposed to NDF increased from OD(595nm) 0.03 after 8 h of exposure and to 0.2 over the following 16 h. Biofilm formation increased with increasing concentrations of FeCl3·6H2O, which suggests that iron is required for S. aureus Xen 31 to form a biofilm. However, when exposed to NDF, biofilm formation decreased significantly in the presence of increasing concentrations of iron. This suggests that NDF may be used to prevent biofilm formation of MRSA and control infection.

  12. Incorporation of Alkylamine into Metal-Organic Frameworks through a Brønsted Acid-Base Reaction for CO2 Capture.

    Science.gov (United States)

    Li, Hao; Wang, Kecheng; Feng, Dawei; Chen, Ying-Pin; Verdegaal, Wolfgang; Zhou, Hong-Cai

    2016-10-06

    The escalating atmospheric CO2 concentration is one of the most urgent environmental concerns of our age. To effectively capture CO2 , various materials have been studied. Among them, alkylamine-modified metal-organic frameworks (MOFs) are considered to be promising candidates. In most cases, alkylamine molecules are integrated into MOFs through the coordination bonds formed between open metal sites (OMSs) and amine groups. Thus, the alkylamine density, as well as the corresponding CO2 uptake in MOFs, are severely restricted by the density of OMSs. To overcome this limit, other approaches to incorporating alkylamine into MOFs are highly desired. We have developed a new method based on Brønsted acid-base reaction to tether alkylamines into Cr-MIL-101-SO3 H for CO2 capture. A systematic optimization of the amine tethering process was also conducted to maximize the CO2 uptake of the modified MOF. Under the optimal amine tethering condition, the obtained tris(2-aminoethyl)amine-functionalized Cr-MIL-101-SO3 H (Cr-MIL-101-SO3 H-TAEA) has a cyclic CO2 uptake of 2.28 mmol g(-1) at 150 mbar and 40 °C, and 1.12 mmol g(-1) at 0.4 mbar and 20 °C. The low-cost starting materials and simple synthetic procedure for the preparation of Cr-MIL-101-SO3 H-TAEA suggest that it has the potential for large-scale production and practical applications.

  13. Rhodanese incorporated in Langmuir and Langmuir-Blodgett films of dimyristoylphosphatidic acid: Physical chemical properties and improvement of the enzyme activity.

    Science.gov (United States)

    de Araújo, Felipe Tejada; Caseli, Luciano

    2016-05-01

    Preserving the catalytic activity of enzymes immobilized in bioelectronics devices is essential for optimal performance in biosensors. Therefore, ultrathin films in which the architecture can be controlled at the molecular level are of interest. In this work, the enzyme rhodanese was adsorbed onto Langmuir monolayers of the phospholipid dimyristoylphosphatidic acid and characterized by surface pressure-area isotherms, polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), and Brewster angle microscopy (BAM). The incorporation of the enzyme (5% in mol) in the lipid monolayer expanded the film, providing small surface domains, as visualized by BAM. Also, amide bands could be identified in the PM-IRRAS spectra, confirming the presence of the enzyme at the air-water interface. Structuring of the enzyme into α-helices was identified in the mixed monolayer and was preserved when the film was transferred from the liquid interface to solids supports as Langmuir-Blodgett (LB) films. The enzyme-lipid LB films were then characterized by fluorescence spectroscopy, PM-IRRAS, and atomic force microscopy. Measurements of the catalytic activity towards cyanide showed that the enzyme accommodated in the LB films preserved more than 87% of the enzyme activity in relation to the homogeneous medium. After 1 month, the enzyme in the LB film maintained 85% of the activity in contrast to the homogeneous medium, which 24% of the enzyme activity was kept. The method presented in this work not only points to an enhanced catalytic activity toward cyanide, but also may explain why certain film architectures exhibit an improved performance.

  14. A split-face comparison of a new hyaluronic acid facial filler containing pre-incorporated lidocaine versus a standard hyaluronic acid facial filler in the treatment of naso-labial folds.

    Science.gov (United States)

    Levy, Phillip M; De Boulle, Koenraad; Raspaldo, Herve

    2009-09-01

    This split-face, single-blind study compared the comfort and ease of injection of a new hyaluronic acid facial filler containing pre-incorporated lidocaine (Juvederm ULTRA 3) versus the established hyaluronic acid facial filler Restylane-Perlane. A total of 126 individuals were treated with both products, randomly assigned to the right or left naso-labial fold. Injector assessment-indicated mean injection pain, pain of massaging the injected area and post-injection discomfort (based on a scale of 0=no pain to 10=extreme pain) were 2.1, 0.9 and 0.4 for Juvederm ULTRA 3, and 4.1, 3.3 and 1.7 for Restylane-Perlane, respectively (p<0.0001). Patient assessment of the same parameters were 2.8, 1.3 and 0.4 for Juvederm ULTRA 3, and 4.9, 3.6 and 1.8 for Restylane-Perlane (p<0.0001). Injectors indicated that 92% of Juvederm ULTRA 3 injections were 'very easy', compared with 21% for Restylane-Perlane. Post-treatment smoothness was comparable, but 95% of individuals preferred Juvederm ULTRA 3 for overall injection comfort. A total of 95% of individuals indicated that Juvederm ULTRA 3 was a more comfortable and gentle experience.

  15. Poloxamer-188 Reduces Muscular Edema After Tourniquet-Induced Ischemia-Reperfusion Injury in Rats

    Science.gov (United States)

    2011-05-01

    Trauma. 2011;70: 1192–1197) Muscle injury, such as ischemia-reperfusion injury (I-R),1blunt trauma injury, electrocution ,2 burn, crush,3 and laceration, is...188 solution (SythRx, Bellaire, TX) contained 150 mg/mL highly purified P-188, 3.08 mg/mL sodium chlo- ride, 2.38 mg/mL sodium citrate, and 0.366 mg...mL citric acid. The placebo solution contained the same ingredients with the exception of P-188. Doses consisted of 1.0 mL/kg body weight of P-188

  16. Neuroprotective effects of pretreatment with quercetin as assessed by acetylcholinesterase assay and behavioral testing in poloxamer-407 induced hyperlipidemic rats.

    Science.gov (United States)

    Braun, Josiane B S; Ruchel, Jader B; Adefegha, Stephen A; Coelho, Ana Paula V; Trelles, Kelly B; Signor, Cristiane; Rubin, Maribel A; Oliveira, Juliana S; Dornelles, Guilherme L; de Andrade, Cinthia M; Castilhos, Lívia G; Leal, Daniela B R

    2017-04-01

    Hyperlipidemia is a group of disorders characterized by excessive lipids in the bloodstream. It is associated with the incidence of cardiovascular diseases and recognized as the most important factor underlying the occurrence of atherosclerosis. This study was conducted to investigate whether pretreatment with quercetin can protect against possible memory impairment and deterioration of the cholinergic system in hyperlipidemic rats. Animals were divided into ten groups (n=7): saline/control, saline/quercetin 5mg/kg, saline/quercetin 25mg/kg, saline/quercetin 50mg/kg, saline/simvastatin (0.04mg/kg), hyperlipidemia, hyperlipidemia/quercetin 5mg/kg, hyperlipidemia/quercetin 25mg/kg, hyperlipidemia/quercetin 50mg/kg and hyperlipidemia/simvastatin. The animals were pretreated with quercetin by oral gavage for a period of 30days and hyperlipidemia was subsequently induced by intraperitoneal administration of a single dose of 500mg/kg of poloxamer-407. Simvastatin was administered after the induction of hyperlipidemia. The results demonstrated that hyperlipidemic rats had memory impairment compared with the saline control group (P<0.001). However, pretreatment with quercetin and simvastatin treatment attenuated the damage caused by hyperlipidemia compared with the hyperlipidemic group (P<0.05). Acetylcholinesterase (AChE) activity in the cerebral hippocampus was significantly (P<0.001) reduced in the hyperlipidemic group compared with the control saline group. Pretreatment with quercetin and simvastatin treatment in the hyperlipidemic groups significantly (P<0.05) increased AChE activity compared with the hyperlipidemic group. Our results thus suggest that quercetin may prevent memory impairment, alter lipid metabolism, and modulate AChE activity in an experimental model of hyperlipidemia.

  17. Preparation and characterization of celecoxib solid dispersions; comparison of poloxamer-188 and PVP-K30 as carriers

    Directory of Open Access Journals (Sweden)

    Alireza Homayouni

    2014-05-01

    Full Text Available Objective(s:Solid dispersion formulation is the most promising strategy to improve oral bioavailability of poorly water soluble drugs. The aim of this study was to compare the effect of polyvinylpyrrolidone K30 (PVP and poloxamer-188 (PLX as carrier in solid dispersion formulations of celecoxib (CLX. Materials and Methods: Solid dispersions of CLX:PVP or CLX:PLX were prepared at different ratios (2:1, 1:1, 1:2, 1:4, 1:6 by solvent evaporation and melting methods, respectively. The characterization of samples was performed using differential scanning calorimetery (DSC, X-Ray powder diffraction (XRPD and Fourier transform infrared spectroscopy (FT-IR. The Gordon-Taylor equation was used to estimate the Tg of solid dispersion systems and the possibility of the interaction between CLX and PVP. Also, the dissolution rate of all samples was determined. Results: DSC and XRPD analyses confirmed the presence of amorphous state of drug in solid dispersion systems. FT-IR studies showed CLX could participate in hydrogen bonding with PVP whilst no specific interaction between CLX and PLX was observed. Both PVP and PLX enhanced the dissolution rate of drug in solid dispersion samples. The dissolution rate was dependent on the ratio of drug: carrier. Interestingly, the solid dispersion samples of PLX at 2:1 and 1:1 drug: carrier showed slower dissolution rate than pure CLX, whilst these results were not observed for PVP. Conclusion: The effect of PVP on dissolution rate enhancement was more pronounced compared to the other carrier. Having a higher Tg and more effect on dissolution rate, PVP could be considered as a more suitable carrier compared to PLX in solid dispersion formulation of CLX.

  18. Modified thermoresponsive Poloxamer 407 and chitosan sol-gels as potential sustained-release vaccine delivery systems.

    Science.gov (United States)

    Kojarunchitt, Thunjiradasiree; Baldursdottir, Stefania; Dong, Yao-Da; Boyd, Ben J; Rades, Thomas; Hook, Sarah

    2015-01-01

    Thermoresponsive, particle-loaded, Poloxamer 407 (P407)-Pluronic-R® (25R4) or chitosan-methyl cellulose (MC) formulations were developed as single-dose, sustained release vaccines. The sol-gels, loaded either with a particulate vaccine (cubosomes) or soluble antigen (ovalbumin) and adjuvants (Quil A and monophosphoryl lipid A), were free-flowing liquids at room temperature and formed stable gels at physiological temperatures. Rheological results showed that both systems meet the criteria of being thermoresponsive gels. The P407-25R4 sol-gels did not significantly sustain the release of antigen in vivo while the chitosan-MC sol-gels sustained the release of antigen up to at least 14 days after administration. The chitosan-MC sol-gels stimulated both cellular and humoral responses. The inclusion of cubosomes in the sol-gels did not provide a definitive beneficial effect. Further analysis of the formulations with small-angle X-ray scattering (SAXS) revealed that while cubosomes were stable in chitosan-MC gels they were not stable in P407-25R4 formulations. The reason for the mixed response to cubosome-loaded vehicles requires more investigation, however it appears that the cubosomes did not facilitate synchronous vaccine release and may in fact retard release, reducing efficacy in some cases. From these results, chitosan-MC sol-gels show potential as sustained release vaccine delivery systems, as compared to the P407-25R4 system that had a limited ability to sustain antigen release.

  19. The influence of repeated administration of poloxamer 407 on serum lipoproteins and protease activity in mouse liver and heart.

    Science.gov (United States)

    Korolenko, Tatyana A; Tuzikov, Fedor V; Johnston, Thomas P; Tuzikova, Natalia A; Kisarova, Yana A; Zhanaeva, Svetlana Ya; Alexeenko, Tatyana V; Zhukova, Natalia A; Brak, Ivan V; Spiridonov, Victor K; Filjushina, Elena E; Cherkanova, Marina S; Monoszon, Anna A

    2012-11-01

    The effects of repeated administration of poloxamer 407 (P-407) on lipoprotein-cholesterol (LP-C) and lipoprotein-triglyceride (LP-TG) fractions and subfractions, as well as the effect on liver and heart proteases, were studied. Repeated administration of P-407 to male CBA mice resulted in a model of atherosclerosis with increased diastolic blood pressure; there was a drastic increase in total serum cholesterol and especially TG. A novel small-angle X-ray scattering method for the determination of the fractional and subfractional composition of LP-C and LP-TG was used. In chronically P-407-treated mice, P-407 significantly increased atherogenic low-density lipoprotein C (LDL-C) fractions, as well as intermediate-density lipoprotein C (IDL-C), and LDL₁₋₃-C subfractions, and very-low-density lipoprotein-C (VLDL-C) fractions, as well as VLDL₁₋₂-C and VLDL₃₋₅-C subfractions), to a lesser extent, the total anti-atherogenic high-density lipoprotein C (HDL-C) fraction, as well as HDL₂-C and HDL₃-C subfractions. Additionally, we demonstrated an increase in the serum chitotriosidase activity, without significant changes in serum matrix metalloprotease (MMP) activity. Morphological changes observed in P-407-treated mice included atherosclerosis in the heart and storage syndrome in the liver macrophages. P-407 significantly increased the activity of cysteine, aspartate proteases, and MMPs in the heart, and only the activity of cathepsin B and MMPs in the liver of mice. Thus, repeated administration of P-407 to mice induced atherosclerosis secondary to sustained dyslipidemia and formation of foamy macrophages in liver, and also modulated the activity of heart and liver proteases.

  20. Intracoronary Poloxamer 188 Prevents Reperfusion Injury in a Porcine Model of ST-Segment Elevation Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Jason A. Bartos, MD, PhD

    2016-06-01

    Full Text Available Poloxamer 188 (P188 is a nonionic triblock copolymer believed to prevent cellular injury after ischemia and reperfusion. This study compared intracoronary (IC infusion of P188 immediately after reperfusion with delayed infusion through a peripheral intravenous catheter in a porcine model of ST-segment elevation myocardial infarction (STEMI. STEMI was induced in 55 pigs using 45 min of endovascular coronary artery occlusion. Pigs were then randomized to 4 groups: control, immediate IC P188, delayed peripheral P188, and polyethylene glycol infusion. Heart tissue was collected after 4 h of reperfusion. Assessment of mitochondrial function or infarct size was performed. Mitochondrial yield improved significantly with IC P188 treatment compared with control animals (0.25% vs. 0.13%, suggesting improved mitochondrial morphology and survival. Mitochondrial respiration and calcium retention were also significantly improved with immediate IC P188 compared with control animals (complex I respiratory control index: 7.4 vs. 3.7; calcium retention: 1,152 nmol vs. 386 nmol. This benefit was only observed with activation of complex I of the mitochondrial respiratory chain, suggesting a specific effect from ischemia and reperfusion on this complex. Infarct size and serum troponin I were significantly reduced by immediate IC P188 infusion (infarct size: 13.9% vs. 41.1%; troponin I: 19.2 μg/l vs. 77.4 μg/l. Delayed P188 and polyethylene glycol infusion did not provide a significant benefit. These results demonstrate that intracoronary infusion of P188 immediately upon reperfusion significantly reduces cellular and mitochondrial injury after ischemia and reperfusion in this clinically relevant porcine model of STEMI. The timing and route of delivery were critical to achieve the benefit.

  1. Effect of Rheology and Poloxamers Properties on Release of Drugs from Silicon Dioxide Gel-Filled Hard Gelatin Capsules-A Further Enhancement of Viability of Liquid Semisolid Matrix Technology.

    Science.gov (United States)

    Sultana, Misbah; Butt, Mobashar Ahmad; Saeed, Tariq; Mahmood, Rizwan; Ul Hassan, Saeed; Hussain, Khalid; Raza, Syed Atif; Ahsan, Muhammad; Bukhari, Nadeem Irfan

    2016-12-08

    The liquid and semisolid matrix technology, filling liquids, semi-solids and gels in hard gelatin capsule are promising, thus, there is a need of enhanced research interest in the technology. Therefore, the present study was aimed to investigate isoniazid (freely soluble) and metronidazole (slightly soluble) gels filled in hard gelatin capsules for the effect of poloxamers of different viscosities on release of the drugs. Gel of each drug (10% w/w, particle size 180-250 μm), prepared by mixing poloxamer and 8% w/w hydrophilic silicon dioxide (Aerosil® A200), was assessed for rheology, dispersion stability and release profile. Both the drugs remained dispersed in majority of gels for more than 30 days, and dispersions were depended on gels' viscosity, which was further depended on viscosity of poloxamers. A small change in viscosity was noted in gels on storage. FTIR spectra indicated no interactions between components of the gels. The gels exhibited thixotropic and shear-thinning behaviour, which were suitable for filling in hard gelatin capsules without any leakage from the capsules. The release of both drugs from the phase-stable gels for 30 days followed first-order kinetics and was found to be correlated to drugs' solubility, poloxamers' viscosity, polyoxyethylene contents and proportion of block copolymer (poloxamers) in the gels. The findings of the present study indicated that release of drugs of different solubilities (isoniazid and metronidazole) might be modified from gels using different poloxamers and Aerosil® A200.

  2. Separation and concentration effect of f-MWCNTs on electrocatalytic responses of ascorbic acid, dopamine and uric acid at f-MWCNTs incorporated with poly (neutral red) composite films

    Energy Technology Data Exchange (ETDEWEB)

    Yogeswaran, Umasankar [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, No.1, Section 3, Chung-Hsiao East Road, Taipei 106, Taiwan (China); Chen, Shen-Ming [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, No.1, Section 3, Chung-Hsiao East Road, Taipei 106, Taiwan (China)]. E-mail: smchen78@ms15.hinet.net

    2007-05-25

    A novel conductive composite film containing functionalized multi-walled carbon nanotubes (f-MWCNTs) with poly (neutral red) (PNR) was synthesized on glassy carbon electrodes (GC) by potentiostatic method. The composite film exhibited promising electrocatalytic oxidation of mixture of biochemical compounds such as ascorbic acid (AA), dopamine (DA) and uric acid (UA) in pH 4.0 aqueous solutions. It was also produced on gold electrodes by using electrochemical quartz crystal microbalance technique, which revealed that the functional properties of composite film were enhanced because of the presence of both f-MWCNTs and PNR. The surface morphology of the polymer and composite film deposited on transparent semiconductor tin oxide electrodes were studied using scanning electron microscopy and atomic force microscopy. These two techniques showed that the PNR was fibrous and incorporated on f-MWCNTs. The electrocatalytic responses of neurotransmitters at composite films were measured using both cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These experiments revealed that the difference in f-MWCNTs loading present in the composite film affected the electrocatalysis in such a way, that higher the loading showed an enhanced electrocatalytic activity. From further electrocatalysis studies, well separated voltammetric peaks were obtained at the composite film modified GC for AA, DA and UA with the peak separation of 0.17 V between AA-DA and 0.15 V between DA-UA. The sensitivity of the composite film towards AA, DA and UA in DPV technique was found to be 0.028, 0.146 and 0.084 {mu}A {mu}M{sup -1}, respectively.

  3. Influences of Poloxamer on Structure and Morphology of Regenerated Silk Fibroin Gelation%泊洛沙姆对再生丝素蛋白凝胶化结构及形态的影响

    Institute of Scientific and Technical Information of China (English)

    邓春闽; 钟天翼; 许亚娟; 岳晓晓; 明津法; 左保齐

    2013-01-01

    This paper studies the influences of Poloxamer on the structure and morphology of silk fibroin gelation and characterizes the effect of Poloxamer on RSF gelation through scanning electron microscope ( SEM) , infrared spectrum (FTIR) , X-ray diffraction (XRD) and thermoanalysis (TG-DTA). FTIR, XRD and TG-DTA researches show that Poloxamer significantly accelerates RSF gelation transformation after blending with RSF; meanwhile, the smaller the relative molecular mass of Poloxamer in blended solution is, the larger its blending ratio will be and the shorter its gelation time will be, but it has very small influences on the structure and morphology of hydrogel formed. SEM research shows that RSF-Poloxamer gel has a lamellar structure. The reason is that a lot of silk fibroin molecules change from random coil to β-folded structure in its process of gelation. With the increase of Poloxamer content, the lamellar structure of RSF-Poloxamer becomes more and more regular.%研究了泊洛沙姆(Poloxamer)对再生丝素蛋白(RSF)凝胶化结构及形态的影响,利用扫描电镜(SEM)、红外光谱(FTIR)、X射线衍射(XRD)和热分析(TG-DTA)表征了Poloxamer对RSF凝胶化的影响作用.FTIR、XRD和TG-DTA研究表明Poloxamer与RSF共混后极大的加速了RSF的凝胶化转变,并且随着共混溶液中Poloxamer的相对分子质量越小,所占的共混比例越大,其凝胶化时间越短,但对所形成的水凝胶的结构和形态影响很小.SEM研究表明RSF-Poloxamer凝胶为片层状结构,这是由于其凝胶化过程中大量丝素分子由无规卷曲转变为β-折叠结构所致,随着Poloxamer含量的增加,RSF-Poloxamer凝胶的片层结构变得越来越规整.

  4. Quantitative importance of the pentose phosphate pathway determined by incorporation of 13C from [2-13C]- and [3-13C]glucose into TCA cycle intermediates and neurotransmitter amino acids in functionally intact neurons

    DEFF Research Database (Denmark)

    Brekke, Eva Marie; Walls, Anne Byriel; Schousboe, Arne

    2012-01-01

    of (13)C-labeled glucose via the PPP does not appear to contribute to the production of releasable lactate, it contributes to labeling of tricarboxylic acid (TCA) cycle intermediates and related amino acids. Based on glutamate isotopomers, it was calculated that PPP activity accounts for ~6% of glucose...... metabolism in cortical neurons and ~4% in cerebellar neurons. This is the first demonstration that pyruvate generated from glucose via the PPP contributes to the synthesis of acetyl CoA for oxidation in the TCA cycle. Moreover, the fact that (13)C labeling from glucose is incorporated into glutamate proves...

  5. Measurement of binding of basic drugs to acidic phospholipids using surface plasmon resonance and incorporation of the data into mechanistic tissue composition equations to predict steady-state volume of distribution.

    Science.gov (United States)

    Small, Helen; Gardner, Iain; Jones, Hannah M; Davis, John; Rowland, Malcolm

    2011-10-01

    Acidic phospholipid binding plays an important role in determining the tissue distribution of basic drugs. This article describes the use of surface plasmon resonance to measure binding affinity (K(D)) of three basic drugs to phosphatidylserine, a major tissue acidic phospholipid. The data are incorporated into mechanistic tissue composition equations to allow prediction of the steady-state volume of distribution (V(ss)). The prediction accuracy of V(ss) using this approach is compared with the original methodology described by Rodgers et al. (J Pharm Sci 94:1259-1276), in which the binding to acidic phospholipids is calculated from the blood/plasma concentration ratio (BPR). The compounds used in this study [amlodipine, propranolol, and 3-dimethylaminomethyl-4-(4-methylsulfanyl-phenoxy)-benzenesulfonamide (UK-390957)] showed higher affinity binding to phosphatidylserine than to phosphatidylcholine. When the binding affinity to phosphatidylserine was incorporated into mechanistic tissue composition equations, the V(ss) was more accurately predicted for all three compounds by using the surface plasmon resonance measurement than by using the BPR to estimate acidic phospholipid binding affinity. The difference was particularly marked for UK-390957, a sulfonamide that has a high BPR due to binding to carbonic anhydrase. The novel approach described in this article allows the binding affinity of drugs to an acidic phospholipid (phosphatidylserine) to be measured directly and demonstrates the utility of the binding data in the prediction of V(ss).

  6. In vitro selection of tRNAs for efficient four-base decoding to incorporate non-natural amino acids into proteins in an Escherichia coli cell-free translation system.

    Science.gov (United States)

    Taira, Hikaru; Hohsaka, Takahiro; Sisido, Masahiko

    2006-01-01

    Position-specific incorporation of non-natural amino acids into proteins is a useful technique in protein engineering. In this study, we established a novel selection system to obtain tRNAs that show high decoding activity, from a tRNA library in a cell-free translation system to improve the efficiency of incorporation of non-natural amino acids into proteins. In this system, a puromycin-tRNA conjugate, in which the 3'-terminal A unit was replaced by puromycin, was used. The puromycin-tRNA conjugate was fused to a C-terminus of streptavidin through the puromycin moiety in the ribosome. The streptavidin-puromycin-tRNA fusion molecule was collected and brought to the next round after amplification of the tRNA sequence. We applied this system to select efficient frameshift suppressor tRNAs from a tRNA library with a randomly mutated anticodon loop derived from yeast tRNA CCCG Phe. After three rounds of the selection, we obtained novel frameshift suppressor tRNAs which had high decoding activity and good orthogonality against endogenous aminoacyl-tRNA synthetases. These results demonstrate that the in vitro selection system developed here is useful to obtain highly active tRNAs for the incorporation of non-natural amino acid from a tRNA library.

  7. Incorporation of poly(glycidylmethacrylate) grafted bacterial cellulose nano-whiskers in poly(lactic acid) nanocomposites: improved barrier and mechanical properties

    Science.gov (United States)

    Poly(glycidyl methacrylate) (PGMA) was grafted onto bacterial cellulose nanowhiskers (BCNW) by means of a redox-initiated free radical copolymerization reaction. The incorporation of PGMA chains decreased the thermal stability and crystallinity of BCNW. The neat and the PGMA-grafted BCNW were subseq...

  8. Free fatty acid and triacylglycerol forms of CLA isomers are not incorporated equally in the liver but do not lead to differences in bone density and biomarkers of bone metabolism.

    Science.gov (United States)

    DeGuire, Jason R; Weiler, Hope A

    2013-05-01

    Few studies have compared differences between conjugated linoleic acid (CLA) in triacylglycerol (TG) and free fatty acid (FFA) form. This study assessed differences in liver incorporation, mineral mass balance, bone density, and biomarkers of bone metabolism between FFA and TG CLA diets. Rats (n=36) were fed a control (CTRL) or 1% CLA diet in FFA or TG form (1:1 mixture c9, t11: t10, c12). Liver content of c9, t11 CLA from FFA was greater than TG form and CTRL (FFA: 0.05±0.01 vs. TG: 0.02±0.01 vs. CTRL: 0.001±0.001% total fatty acids, PCLA did not differ among groups (P=0.11). No diet differences among groups for growth, bone biomarkers or mass nor mineral balance were found. These findings suggest that c9, t11 CLA in FFA form is preferentially incorporated in the liver but fatty acid forms of CLA do not affect bone or mineral outcomes.

  9. 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.

  10. The incorporation of water-soluble gel matrix into bile acid-based microcapsules for the delivery of viable β-cells of the pancreas, in diabetes treatment: biocompatibility and functionality studies.

    Science.gov (United States)

    Mooranian, Armin; Negrulj, Rebecca; Al-Salami, Hani

    2016-02-01

    In recent studies, we microencapsulated pancreatic β-cells using sodium alginate (SA) and poly-L-ornithine (PLO) and the bile acid, ursodeoxycholic acid (UDCA), and tested the morphology and cell viability post-microencapsulation. Cell viability was low probably due to limited strength of the microcapsules. This study aimed to assess a β-cell delivery system which consists of UDCA-based microcapsules incorporated with water-soluble gel matrix. The polyelectrolytes, water-soluble gel (WSG), polystyrenic sulphate (PSS), PLO and polyallylamine (PAA) at ratios 4:1:1:2.5 with or without 4% UDCA, were incorporated into our microcapsules, and cell viability, metabolic profile, cell functionality, insulin production, levels of inflammation, microcapsule morphology, cellular distribution, UDCA partitioning, biocompatibility, thermal and chemical stabilities and the microencapsulation efficiency were examined. The incorporation of UDCA with PSS, PAA and WSG enhanced cell viability per microcapsule (p < 0.05), cellular metabolic profile (p < 0.01) and insulin production (p < 0.01); reduced the inflammatory release TNF-α (p < 0.01), INF-gamma (p < 0.01) and interleukin-6 (IL-6) (p < 0.01); and ceased the production of IL-1β. UDCA, PSS, PAA and WSG addition did not change the microencapsulation efficiency and resulted in biocompatible microcapsules. Our designed microcapsules showed good morphology and desirable insulin production, cell functionality and reduced inflammatory profile suggesting potential applications in diabetes.

  11. Reclamation of acidic colliery spoil. Part 4. The effects of limestone particle size and depth of incorporation. [Lolium perenne L. ; Trifolium repens L. ; Lotus corniculatus L

    Energy Technology Data Exchange (ETDEWEB)

    Costigan, P.A.; Bradshaw, A.D.; Gemmell, R.P.

    1984-04-01

    The effects of different grades of limestone (up to 2.4 mm diameter) and depths of incorporation (15 and 25 cm) on spoil pH and growth of Lolium perenne L. were measured over 2 years in two field experiments on colliery spoil. A pot experiment was established using three grades of limestone (up to 3 mm diameter) with crops of L. perenne L., Trifolium repens L. or Lotus corniculatus L. The coarser grades of limestone reacted more slowly than the fine grade. When enough limestone was applied, plant growth was not reduced with the coarser grades. There was no evidence that coarser grades became unreactive. Deeper incorporation did improve plant growth over the summer period but not in the winter and the incorporation of the same rate of limestone to a greater depth did not raise pH to the same level. In a pot experiment, spoil pH was affected by crop species. This was attributed to differences in transpiration rates affecting spoil aeration. It appears that coarse limestone particles do have a long-term neutralizing effect provided that sufficient limestone is applied and the particle size does not exceed about 3 mm.

  12. Incorporation of n-3 PUFA and γ-linolenic acid in blood lipids and red blood cell lipids together with their influence on disease activity in patients with chronic inflammatory arthritis - a randomized controlled human intervention trial

    Directory of Open Access Journals (Sweden)

    Springer Monika

    2011-08-01

    Full Text Available Abstract Background and aim Marine n-3 fatty acids and γ-linolenic acid both have anti-inflammatory effects and may be useful to help treat inflammatory diseases. The effects of these alone or combined were examined in patients with arthritis in a randomized controlled trial. Design Patients with rheumatoid arthritis or psoriatic arthritis were randomized into four groups in a double-blind, placebo-controlled parallel designed study. Patients received the respective capsules (1: 3.0 g n-3 LC-PUFA/d; 2: 3.2 g γ-linolenic acid/d; 3: 1.6 g n-3 LC-PUFA + 1.8 g γ-linolenic acid/d; 4: 3.0 g olive oil for a twelve week period. Clinical status was evaluated and blood samples were taken at the beginning and at the end of the period. Differences before and after intervention were tested with paired t-test or with Wilcoxon test for non-normal data distribution. Results 60 patients (54 rheumatoid arthritis, 6 psoriatic arthritis were randomised, 47 finished per protocol. In group 1, the ratio of arachidonic acid (AA/eicosapentaenoic acid (EPA decreased from 6.5 ± 3.7 to 2.7 ± 2.1 in plasma lipids and from 25.1 ± 10.1 to 7.2 ± 4.7 in erythrocyte membranes (p ≤ 0.001. There was no significant influence on AA/EPA ratio due to interventions in group 2-4. In group 2, the intake of γ-linolenic acid resulted in a strong rise of γ-linolenic acid and dihomo-γ-linolenic acid concentrations in plasma lipids, cholesteryl esters, and erythrocyte membranes. The combination of n-3 LC-PUFA and γ-linolenic acid (group 3 led to an increase of γ-linolenic acid and dihomo-γ-linolenic acid concentrations in plasma lipids, cholesteryl esters, and erythrocyte mem-branes. This increase was only half of that in group 2. Conclusions Incorporation of eicosanoid precursor FAs was influenced by an intake of n-3 LC-PUFA and γ-linolenic acid suggesting a possible benefit for therapy of chronic inflammatory diseases. Trial Registration ClinicalTrials NCT01179971

  13. 288.15K-308.15K(Poloxamerl88+乙醇/丙酮+水)三元体系的密度和黏度%Density and Viscosity of Ternary Systems (Poloxamer 188 + Ethanol/Acetone + Water) at Temperatures from 288.15 K to 308.15 K

    Institute of Scientific and Technical Information of China (English)

    刘谦; 张颂红; 沈绍传; 贠军贤; 姚克俭

    2011-01-01

    The densities and viscosities of ternary systems (Poloxamer 188 + ethanol/acetone + water) were measured at 288. i 5, 293.15, 298.15, 303.15, 308.15 K and atmospheric pressure for different mass fractions of Poloxamer 188 (0 to 0.02) in aqueous solution and different solvent volume fractions of ethanol/acetone (0 to 0.3) in Poloxamer 188 aqueous solution. The densities were measured by a pycnometer, while the viscosities were measured using two Ubbelohde capillary viscometers. The correlations of density and viscosity of these ternary systems are obtained by fitting the experimental data at different temperatures, mass fractions and volume fractions.

  14. Incorporation of radio-labelled nucleic acid precursors by Theileria parva in bovine blood and salivary glands of Rhipicephalus appendiculatus ticks

    Energy Technology Data Exchange (ETDEWEB)

    Irvin, A.D.; Boarer, C.D.H.; Kurtti, T.J.; Ocama, J.G.R. (International Lab. for Research on Animal Diseases, Nairobi (Kenya))

    1981-12-01

    The uptake of radio-labelled nucleic acid precursors by blood and tick salivary gland forms of Theileria parva was studied. Piroplasms took up tritiated purines, particularly hypoxanthine, but not pyrimidines. Similar uptake was recorded by T. parva, both in tick saliva and in salivary glands maintained in vitro. Intermediate parasite stages were those most readily labelled in glands; this reflected active nucleic acid synthesis associated with rapid parasite division. Radio-labelling of T. parva in tick salivary glands could be of value in procedures used for concentrating and purifying theilerial sporozoites.

  15. Synthesis of a chiral amino acid with bicyclo[1.1.1]pentane moiety and its incorporation into linear and cyclic antimicrobial peptides.

    Science.gov (United States)

    Pritz, Stephan; Pätzel, Michael; Szeimies, Günter; Dathe, Margitta; Bienert, Michael

    2007-06-01

    The synthesis of the lipophilic chiral amino acid 1 bearing the bicyclo[1.1.1]pentane moiety is described. Linear and cyclic hexapeptides of the type Arg-Arg-Xaa-Yaa-Arg-Phe containing 1 instead of one or two tryptophan residues are prepared by solid phase peptide synthesis and the antimicrobial and hemolytic activity of the peptides obtained are discussed.

  16. Synthesis of a Hoechst 32258 analogue amino acid building block for direct incorporation of a fluorescent, high-affinity DNA binding motif into peptides

    DEFF Research Database (Denmark)

    Behrens, C; Harrit, N; Nielsen, P E

    2001-01-01

    The synthesis of a new versatile "Hoechst 33258-like" Boc-protected amino acid building block for peptide synthesis is described. It is demonstrated that this new ligand is an effective mimic of Hoechst 33258 in terms of DNA affinity and sequence specificity. Furthermore, this minor groove binder...

  17. Marine n-3 fatty acids are incorporated into atrial tissue but do not correlate with postoperative atrial fibrillation in cardiac surgery

    DEFF Research Database (Denmark)

    Gu, J; Lundbye-Christensen, Søren; Eschen, Rikke Bülow;

    2016-01-01

    OBJECTIVES: Postoperative new-onset atrial fibrillation (POAF) in cardiac surgery is associated with increased morbidity and mortality. Because n-3 polyunsaturated fatty acids (n-3 PUFA) have an antiarrhythmic effect, we hypothesized that a high content of marine n-3 PUFA in the atrial wall was a...

  18. 药用高分子材料泊洛沙姆的研究进展%Research on the Progress of Medicinal Polymer Poloxamer

    Institute of Scientific and Technical Information of China (English)

    黄海亮; 张海涛; 赵东永

    2016-01-01

    泊洛沙姆在药物制剂领域广泛应用,通常用作基质、增溶剂、稳定剂、乳化剂、吸收促进剂、固体分散体载体等,以控制药物释放,提高药物的稳定性,增加难溶性药物的溶解度,提高药物的生物利用度。%Poloxamer commonly used as thickening solvent, emulsifier, matrix, solid dispersion carrier, absorption enhancer and stabilizer, in order to increase the solubility of drugs dififcult to dissolve, improve drug stability, controlled drug release and improve biological drug utilization in pharmaceutics ifelds have a wide range of applications.

  19. Synthesis, structure elucidation, biological screening, molecular modeling and DNA binding of some Cu(II) chelates incorporating imines derived from amino acids

    Science.gov (United States)

    Abdel-Rahman, Laila H.; Abu-Dief, Ahmed M.; Ismael, Mohammed; Mohamed, Mounir A. A.; Hashem, Nahla Ali

    2016-01-01

    Three tridentate Schiff bases amino acids were prepared by direct condensation of 3-methoxysalicylaldehyde (MS) or 4-diethylaminosalicylaldehyde (DS) with α-amino acid ligands [L-phenylalanine (P), L-histidine (H) and DL-tryptophan (T)]. The prepared Schiff bases amino acids were investigated by melting points, elemental analysis, 1HNMR and 13CNMR, IR, UV-Vis spectra, conductivity and magnetic measurements analyses. Subsequently, copper was introduced and Cu(II) complexes formed. These complexes were analyzed by thermal and elemental analyses and further investigated by FT-IR and UV/Vis spectroscopies. The experimental results indicating that all Cu(II) complexes contain hydrated water molecules (except DSPCu complex) and don't contain coordinated water molecules. The kinetic and thermal parameters were extracted from the thermal data using Coast and Redfern method. The molar conductance values of the Schiff base amino acid ligands and their Cu(II) complexes were relatively low, showing that these compounds have non-electrolytic nature. Magnetic susceptibility measurements showed the diamagnetic nature of the Schiff base amino acid ligands and paramagnetic nature of their complexes. Additionally, a spectrophotometric method was determined to extract their stability constants. It was found that the complexes possess 1:2 (M:L) stoichiometry. The results suggested that 3-methoxysalicylaldehyde and 4-diethylaminosalicylaldehyde amino acid Schiff bases behave as monobasic tridentate ONO ligands and coordinate Cu(II) ions in octahedral geometry according to the general formula [Cu(HL)2]·nH2O. To further understanding the structural and electronic properties of these complexes, Density Functional Theory (DFT) calculations were employed and provided a satisfactory description. The optimized structures of MST Schiff base ligand and its complex were calculated using DFT. The antimicrobial activity of the Schiff base ligands and their complexes were screened against some

  20. Conformationally locked aryl C-nucleosides: synthesis of phosphoramidite monomers and incorporation into single-stranded DNA and LNA (locked nucleic acid)

    DEFF Research Database (Denmark)

    Babu, B. Ravindra; Prasad, Ashok K.; Trikha, Smriti

    2002-01-01

    . The phosphoramidite approach was used for automated incorporation of the LNA-type beta-configured C-aryl monomers 17a-17e into short DNA and 2'-OMe-RNA/LNA strands. It is shown that universal hybridization can be obtained with a conformationally restricted monomer as demonstrated most convincingly for the pyrene LNA......Synthesis of a series of LNA-type beta-configured C-aryl nucleosides, i.e., 2'- O,4'-C-methylene-beta-D-ribofuranosyl derivatives containing phenyl, 4-fluoro-3-methylphenyl, 1-naphthyl, 1-pyrenyl and 2,4,5-trimethylphenyl groups as aglycons, has been accomplished. The key synthetic step consisted...... monomer 17d, both in a DNA context and in an RNA-like context. Increased binding affinity of oligonucleotide probes for universal hybridization can be induced by combining the pyrene LNA monomer 17d with affinity-enhancing 2'-OMe-RNA/LNA monomers....

  1. Stabilization of Parallel Triplexes by Twisted Intercalating Nucleic Acids (TINAs) Incorporating 1,2,3-Triazole Units and Prepared by Microwave-Accelerated Click Chemistry

    DEFF Research Database (Denmark)

    Géci, Imrich; Filitchev, Vyacheslav Viatcheslav; Pedersen, Erik Bjerreg.

    2007-01-01

    and acceleration by microwave irradiation. The twisted intercalating nucleic acids (TINAs) obtained in these reactions, possessing bulged insertions of (R)-3-O-{4-[1-(pyren-1-yl)-1H-1,2,3-triazol-4-yl]benzyl}glycerol (7), formed parallel triplexes with thermal stabilities of 20.0, 34.0, and 40.0 °C at pH 7...

  2. Incorporation of post-translational modified amino acids as an approach to increase both chemical and biological diversity of conotoxins and conopeptides.

    Science.gov (United States)

    Espiritu, Michael J; Cabalteja, Chino C; Sugai, Christopher K; Bingham, Jon-Paul

    2014-01-01

    Bioactive peptides from Conus venom contain a natural abundance of post-translational modifications that affect their chemical diversity, structural stability, and neuroactive properties. These modifications have continually presented hurdles in their identification and characterization. Early endeavors in their analysis relied on classical biochemical techniques that have led to the progressive development and use of novel proteomic-based approaches. The critical importance of these post-translationally modified amino acids and their specific assignment cannot be understated, having impact on their folding, pharmacological selectivity, and potency. Such modifications at an amino acid level may also provide additional insight into the advancement of conopeptide drugs in the quest for precise pharmacological targeting. To achieve this end, a concerted effort between the classical and novel approaches is needed to completely elucidate the role of post-translational modifications in conopeptide structure and dynamics. This paper provides a reflection in the advancements observed in dealing with numerous and multiple post-translationally modified amino acids within conotoxins and conopeptides and provides a summary of the current techniques used in their identification.

  3. De novo biosynthesis of linoleic acid and its conversion to the hydrocarbon (Z,Z)-6,9-heptadecadiene in the astigmatid mite, Carpoglyphus lactis: incorporation experiments with 13C-labeled glucose.

    Science.gov (United States)

    Shimizu, Nobuhiro; Naito, Michiya; Mori, Naoki; Kuwahara, Yasumasa

    2014-02-01

    De novo biosynthesis of linoleic acid (LA) and its conversion to (Z,Z)-6,9-heptadecadiene were examined in Carpoglyphus lactis (Acarina, Carpoglyphidae). Experiments involving (13)C-administration using [1-(13)C]-d-glucose revealed that (13)C atoms were incorporated into LA of total lipid extracted from the mite, resulting in labeling of all even-numbered carbons. This result demonstrated that LA was produced from (13)C-labeled acetyl-CoA, which is indicative of direct de novo biosynthesis. In these feeding experiments involving [1-(13)C]-D-glucose, (13)C atoms were also incorporated into (Z,Z)-6,9-heptadecadiene, which is one of the major secretory components in the mite. The labeling pattern of (Z,Z)-6,9-heptadecadiene at odd-numbered carbons agreed well with that of LA after loss of the carboxyl carbon. It was concluded that the mites could stably convert LA into (Z,Z)-6,9-heptadecadiene without the dietary requirement of this essential fatty acid.

  4. Attempting to monitor the incorporation of deuterium into indole-3-acetic acid and tryptophan in Zea mays grown on deuterium oxide labeled water

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, P.J.; Bandurski, R.S. (Michigan State Univ., East Lansing (USA))

    1989-04-01

    We are attempting to determine when seedlings of Zea mays sweet corn, var. Silver Queen begin de novo biosynthesis of tryptophan and indole-3-acetic acid (IAA). We wish to use the general precursor, deuterium labeled water, to minimize assumptions as to the biosynthetic route. Protium in positions 2, 4, 5, 6 7 of the indole ring are non-exchangeable. IAA and tryptophan synthesized via the shikimic acid pathway would contain deuterium in one or more of these positions . The protium on the indene nitrogen, the carboxyl, the amino group, or the protium alpha to the carboxyl exchange readily and so are removed prior to analysis by base catalyzed exchange. The IAA, or trypotophan, is then purified by DEAE, Dowex 50, and two HPLC steps. IAA is methylated with diazomethane and analyzed by GC/MS. Trytophan is acetylated with triethylamine-acetic anhydride and then methylated with diazomethane and analyzed by GC/MS. Results of these studies on plants grown for varying lengths of time and under various light and nutrient conditions will be reported.

  5. Influence of nanographene platelets (NGP) incorporation on Fe3O4 nanoparticles as materials additives for enhancement thermal properties stearic acid

    Science.gov (United States)

    Nuryadin, M. K.; Andiarto, R.; Taufik, A.; Saleh, R.

    2016-11-01

    In this work, Fe3O4 nanoparticles, and Fe3O4/NGP composite were used as material additive for enhancement thermal properties of stearic acid (SA). The both material additive were synthesized using sol-gel method. Phase change material (PCM) composites SA-Fe3O4 and Sa-Fe3O4/NGP mixtures were made through the dispersion technique with three different weight % ratio of material additives into stearic acid: 1 wt.%, 3 wt.%, and 5 wt.%. X-Ray Diffractometer (XRD) and Fourier Transform Infrared (FTIR) spectroscopy were used to investigate the structural properties. Magnetic properties also measured by vibrating sample magnetometer (VSM) to see influence of NGP in PCM composites. Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) were used in order to analyse the thermal properties of the samples. The results show an enhancement of the latent heat, thermal stability as well as specific heat by the presence of material additives in SA. Compare to SA- Fe3O4, SA-Fe3O4/NGP show better improvement in enhancement of thermal performance of SA. The improvement by about 41.2% in specific heat and 21.2% in latent heat.

  6. Probing the active site of MIO-dependent aminomutases, key catalysts in the biosynthesis of beta-amino acids incorporated in secondary metabolites.

    Science.gov (United States)

    Cooke, Heather A; Bruner, Steven D

    2010-09-01

    The tyrosine aminomutase SgTAM produces (S)-ss-tyrosine from L-tyrosine in the biosynthesis of the enediyne antitumor antibiotic C-1027. This conversion is promoted by the methylideneimidazole-5-one (MIO) prosthetic group. MIO was first identified in the homologous family of ammonia lyases, which deaminate aromatic amino acids to form alpha,ss-unsaturated carboxylates. Studies of substrate specificity have been described for lyases but there have been limited reports in altering the substrate specificity of aminomutases. Furthermore, it remains unclear as to what structural properties are responsible for catalyzing the presumed readdition of the amino group into the alpha,ss-unsaturated intermediates to form ss-amino acids. Attempts to elucidate specificity and mechanistic determinants of SgTAM have also proved to be difficult as it is recalcitrant to perturbations to the active site via mutagenesis. An X-ray cocrystal structure of the SgTAM mutant of the catalytic base with L-tyrosine verified important substrate binding residues as well as the enzymatic base. Further mutagenesis revealed that removal of these crucial interactions renders the enzyme inactive. Proposed structural determinants for mutase activity probed via mutagenesis, time-point assays and X-ray crystallography revealed a complicated role for these residues in maintaining key quaternary structure properties that aid in catalysis. Copyright 2010 Wiley Periodicals, Inc.

  7. Selective detection of dopamine in the presence of uric acid using a gold nanoparticles-poly(luminol) hybrid film and multi-walled carbon nanotubes with incorporated β-cyclodextrin modified glassy carbon electrode.

    Science.gov (United States)

    Jia, Dong; Dai, Jianyuan; Yuan, Hongyan; Lei, Ling; Xiao, Dan

    2011-10-15

    Gold nanoparticles-poly(luminol) (Plu-AuNPs) hybrid film and multi-walled carbon nanotubes with incorporated β-cyclodextrin modified glassy carbon electrode (β-CD-MWCNTs/Plu-AuNPs/GCE) was successfully prepared for simultaneous determination of dopamine (DA) and uric acid (UA). The surface of the modified electrode has been characterized by X-ray photo-electron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscope (SEM) and transmission electron microscope (TEM). Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) have been used to investigate the β-CD-MWCNTs/Plu-AuNPs composite film. Gold nanoparticles anchored into poly(luminol) film exhibited catalytic activity for DA. MWCNTs with incorporated β-CD can greatly promote the direct electron transfer. In 0.10 M phosphate buffer solution (PBS, pH 7.0), the DPV response of the β-CD-MWCNTs/Plu-AuNPs/GCE sensor to DA is about 8-fold as compared with the Plu-AuNPs/GCE sensor, and the detection limit for DA is about one order of magnitude lower than the Plu-AuNPs/GCE sensor. The steady-state current response increases linearly with DA concentration from 1.0 × 10(-6) to 5.6 × 10(-5)M with a low detection limit (S/N=3) of 1.9 × 10(-7)M. Moreover, the interferences of ascorbic acid (AA) and uric acid (UA) are effectively diminished. The applicability of the prepared electrode has been demonstrated by measuring DA contents in dopamine hydrochloride injection.

  8. Platinum nanoparticles incorporated in silsesquioxane for use in LbL films for the simultaneous detection of dopamine and ascorbic acid

    Science.gov (United States)

    dos Santos, Vagner; de Jesus, Cliciane Guadalupe; dos Santos, Monalisa; Canestraro, Carla Daniele; Zucolotto, Valtencir; Fujiwara, Sérgio Toshio; Garcia, Jarem Raul; Pessoa, Christiana Andrade; Wohnrath, Karen

    2012-09-01

    We describe the preparation of platinum nanoparticles (PtNPs) using the 3- n-propylpyridinium silsesquioxane chloride (SiPy+Cl-) as a nanoreactor and stabilizer. The formation of PtNPs was monitored by UV-Vis spectroscopy by measuring the decrease in the intensity of the band at 375 nm, which is attributed to the electronic absorption of PtCl6 2- ions. TEM images of Pt-SiPy+Cl- nanohybrid indicated an average size of 3-40 nm for PtNPs. The Pt-SiPy+Cl- was used as a polycation in the preparation of layer-by-layer films (LbL) on a glass substrate coated with fluorine-doped tin oxide (FTO) alternating with the polyanion poly(vinyl sulfonic acid) (PVS). The films were electrochemically tested in sulfuric acid to confirm the deposition of Pt-SiPy+Cl- onto the LbL films, observing the adsorption and desorption of hydrogen ( E pa = 0.1 V) and by the redox process of formation for PtO with E pa = 1.3 V and E pc = 0.65 V. FTIR and Raman spectra confirmed the presence of the PVS and Pt-SiPy+Cl- in the LbL films. A linear increase in the absorbance in the UV-Vis spectra of the Pt-SiPy+Cl- at 258 nm (π → π* transition of the pyridine groups) with a number of Pt-SiPy+Cl-/PVS or PVS/SiPy+Cl- bilayers ( R = 0.992) was observed. These LbL films were tested for the determination of dopamine (DA) in the presence of ascorbic acid (AA) with a detection limit (DL) on the order of 2.6 × 10-6 mol L-1 and a quantification limit (QL) of 8.6 × 10-6 mol L-1. The films exhibited a good repeatability and reproducibility, providing a potential difference of 550 mV for the oxidation of DA with AA interferent.

  9. Platinum nanoparticles incorporated in silsesquioxane for use in LbL films for the simultaneous detection of dopamine and ascorbic acid

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Vagner dos; Guadalupe de Jesus, Cliciane; Santos, Monalisa dos [Universidade Estadual de Ponta Grossa, UEPG, Department of Chemistry (Brazil); Canestraro, Carla Daniele [Universidade Federal do Parana, UFPR, Department of Physics (Brazil); Zucolotto, Valtencir [IFSC, Universidade de Sao Paulo (Brazil); Fujiwara, Sergio Toshio; Garcia, Jarem Raul; Andrade Pessoa, Christiana; Wohnrath, Karen, E-mail: karen.woh@gmail.com [Universidade Estadual de Ponta Grossa, UEPG, Department of Chemistry (Brazil)

    2012-09-15

    We describe the preparation of platinum nanoparticles (PtNPs) using the 3-n-propylpyridinium silsesquioxane chloride (SiPy{sup +}Cl{sup -}) as a nanoreactor and stabilizer. The formation of PtNPs was monitored by UV-Vis spectroscopy by measuring the decrease in the intensity of the band at 375 nm, which is attributed to the electronic absorption of PtCl{sub 6}{sup 2-} ions. TEM images of Pt-SiPy{sup +}Cl{sup -} nanohybrid indicated an average size of 3-40 nm for PtNPs. The Pt-SiPy{sup +}Cl{sup -} was used as a polycation in the preparation of layer-by-layer films (LbL) on a glass substrate coated with fluorine-doped tin oxide (FTO) alternating with the polyanion poly(vinyl sulfonic acid) (PVS). The films were electrochemically tested in sulfuric acid to confirm the deposition of Pt-SiPy{sup +}Cl{sup -} onto the LbL films, observing the adsorption and desorption of hydrogen (E{sub pa} = 0.1 V) and by the redox process of formation for PtO with E{sub pa} = 1.3 V and E{sub pc} = 0.65 V. FTIR and Raman spectra confirmed the presence of the PVS and Pt-SiPy{sup +}Cl{sup -} in the LbL films. A linear increase in the absorbance in the UV-Vis spectra of the Pt-SiPy{sup +}Cl{sup -} at 258 nm ({pi} {yields} {pi}* transition of the pyridine groups) with a number of Pt-SiPy{sup +}Cl{sup -}/PVS or PVS/SiPy{sup +}Cl{sup -} bilayers (R = 0.992) was observed. These LbL films were tested for the determination of dopamine (DA) in the presence of ascorbic acid (AA) with a detection limit (DL) on the order of 2.6 Multiplication-Sign 10{sup -6} mol L{sup -1} and a quantification limit (QL) of 8.6 Multiplication-Sign 10{sup -6} mol L{sup -1}. The films exhibited a good repeatability and reproducibility, providing a potential difference of 550 mV for the oxidation of DA with AA interferent.

  10. Changes in Soil Chemical Properties and Lettuce Yield Response Following Incorporation of Biochar and Cow Dung to Highly Weathered Acidic Soils

    DEFF Research Database (Denmark)

    Agyei Frimpong, Kwame; Amoakwah, Emmanuel; Osei, Benjamin A

    2016-01-01

    Soil fertility decline is a major biophysical constraint to crop production in Sub-Saharan Africa. Therefore, there is an urgent need for sustainable soil fertility replenishment strategies to improve soil quality for enhanced crop production. In a laboratory incubation experiment, biochar (2......% and 5%) and cow dung (20 tons ha-1) were applied singly, and 2% biochar was applied in combination with two rates of cow dung (10 and 20 tons ha-1) in a coastal savanna soil repacked at a bulk density of 1.4 g cm-3 at a constant soil water filled capacity of 60% for 40 days. The same treatments were...... imposed on two highly weathered, acidic soils from the coastal savanna and tropical rainforest agroecological zones of Ghana, respectively, to elucidate their effect on yield of lettuce. The study showed that application of biochar solely or in combination with cow dung increased soil pH, total organic...

  11. Techno-economic analysis for incorporating a liquid-liquid extraction system to remove acetic acid into a proposed commercial scale biorefinery.

    Science.gov (United States)

    Aghazadeh, Mahdieh; Engelberth, Abigail S

    2016-07-08

    Mitigating the effect of fermentation inhibitors in bioethanol plants can have a great positive impact on the economy of this industry. Liquid-liquid extraction (LLE) using ethyl acetate is able to remove fermentation inhibitors-chiefly, acetic acid-from an aqueous solution used to produce bioethanol. The fermentation broth resulting from LLE has higher performance for ethanol yield and its production rate. Previous techno-economic analyses focused on second-generation biofuel production did not address the impact of removing the fermentation inhibitors on the economic performance of the biorefinery. A comprehensive analysis of applying a separation system to mitigate the fermentation inhibition effect and to provide an analysis on the economic impact of removal of acetic acid from corn stover hydrolysate on the overall revenue of the biorefinery is necessary. This study examines the pros and cons associated with implementing LLE column along with the solvent recovery system into a commercial scale bioethanol plant. Using details from the NREL-developed model of corn stover biorefinery, the capital costs associated with the equipment and the operating cost for the use of solvent were estimated and the results were compared with the profit gain due to higher ethanol production. Results indicate that the additional capital will add 1% to the total capital and manufacturing cost will increase by 5.9%. The benefit arises from the higher ethanol production rate and yield as a consequence of inhibitor extraction and results in a $0.35 per gallon reduction in the minimum ethanol selling price (MESP). © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:971-977, 2016. © 2016 American Institute of Chemical Engineers.

  12. Incorporating Amino Acid Esters into Catalysts for Hydrogen Oxidation: Steric and Electronic Effects and the Role of Water as a Base

    Energy Technology Data Exchange (ETDEWEB)

    Lense, Sheri; Ho, Ming-Hsun; Chen, Shentan; Jain, Avijita; Raugei, Simone; Linehan, John C.; Roberts, John A. S.; Appel, Aaron M.; Shaw, Wendy

    2012-10-08

    Four derivatives of a hydrogen oxidation catalyst, [Ni(PCy2NBn-R2)2]2+ (Cy = cyclohexyl, Bn = benzyl, R = OMe, COOMe, CO-alanine-methyl ester, CO-phenylalanine-methyl ester), have been prepared to investigate steric and electronic effects on catalysis. Each complex was characterized spectroscopically and electrochemically, and thermodynamic data were determined. Crystal structures are also reported for the -OMe and -COOMe derivatives. All four catalysts were found to be active for H2 oxidation. The methyl ester (R = COOMe) and amino acid ester containing complexes (R = CO-alanine-methyl ester or CO-phenylalanine-methyl ester) had rates slower (4 s–1) than that of the parent complex (10 s–1), in which R = H, which is consistent with the lower amine pKa's and less favorable ΔGH2's found for these electron-withdrawing substituents. Dynamic processes for the amino acid ester containing complexes were also investigated and found not to hinder catalysis. The electron-donating methyl ether derivative (R = OMe) was prepared to compare electronic effects and has a catalytic rate similar to that of the parent complex. In the course of these studies, it was found that water could act as a weak base for H2 oxidation, although catalytic turnover requires a higher potential and utilizes a different sequence of catalytic steps than when using a base with a higher pKa. Finally and importantly, these catalysts provide a foundation upon which larger peptides can be attached to [Ni(PCy2NBn2)2]2+ hydrogen oxidation catalysts in order to more fully investigate and implement the effects of the outer coordination sphere.

  13. OH-PRED: prediction of protein hydroxylation sites by incorporating adapted normal distribution bi-profile Bayes feature extraction and physicochemical properties of amino acids.

    Science.gov (United States)

    Jia, Cang-Zhi; He, Wen-Ying; Yao, Yu-Hua

    2017-03-01

    Hydroxylation of proline or lysine residues in proteins is a common post-translational modification event, and such modifications are found in many physiological and pathological processes. Nonetheless, the exact molecular mechanism of hydroxylation remains under investigation. Because experimental identification of hydroxylation is time-consuming and expensive, bioinformatics tools with high accuracy represent desirable alternatives for large-scale rapid identification of protein hydroxylation sites. In view of this, we developed a supporter vector machine-based tool, OH-PRED, for the prediction of protein hydroxylation sites using the adapted normal distribution bi-profile Bayes feature extraction in combination with the physicochemical property indexes of the amino acids. In a jackknife cross validation, OH-PRED yields an accuracy of 91.88% and a Matthew's correlation coefficient (MCC) of 0.838 for the prediction of hydroxyproline sites, and yields an accuracy of 97.42% and a MCC of 0.949 for the prediction of hydroxylysine sites. These results demonstrate that OH-PRED increased significantly the prediction accuracy of hydroxyproline and hydroxylysine sites by 7.37 and 14.09%, respectively, when compared with the latest predictor PredHydroxy. In independent tests, OH-PRED also outperforms previously published methods.

  14. Improved small molecule drug release from in situ forming poly(lactic-co-glycolic acid) scaffolds incorporating poly(β-amino ester) and hydroxyapatite microparticles.

    Science.gov (United States)

    Fisher, Paul D; Palomino, Pablo; Milbrandt, Todd A; Hilt, J Zach; Puleo, David A

    2014-01-01

    In situ forming implants are an attractive choice for controlled drug release into a fixed location. Currently, rapidly solidifying solvent exchange systems suffer from a high initial burst, and sustained release behavior is tied to polymer precipitation and degradation rate. The present studies investigated addition of hydroxyapatite (HA) and drug-loaded poly(β-amino ester) (PBAE) microparticles to in situ forming poly(lactic-co-glycolic acid) (PLGA)-based systems to prolong release and reduce burst. PBAEs were synthesized, imbibed with simvastatin (osteogenic) or clodronate (anti-resorptive), and then ground into microparticles. Microparticles were mixed with or without HA into a PLGA solution, and the mixture was injected into buffer, leading to precipitation and creating solid scaffolds with embedded HA and PBAE microparticles. Simvastatin release was prolonged through 30 days, and burst release was reduced from 81 to 39% when loaded into PBAE microparticles. Clodronate burst was reduced from 49 to 32% after addition of HA filler, but release kinetics were unaffected after loading into PBAE microparticles. Scaffold dry mass remained unchanged through day 15, with a pronounced increase in degradation rate after day 30, while wet scaffolds experienced a mass increase through day 25 due to swelling. Porosity and pore size changed throughout degradation, likely due to a combination of swelling and degradation. The system offers improved release kinetics, multiple release profiles, and rapid solidification compared to traditional in situ forming implants.

  15. Electronically tailoring 3D flower-like graphene via alumina doping and incorporating Co as an efficient oxygen electrode catalyst in both alkaline and acid media

    Science.gov (United States)

    Ma, Xiu-Xiu; He, Xing-Quan

    2017-06-01

    3D graphene-based electrode catalysts have intrigued tremendous research in energy conversion and storage systems not only for the intrinsic properties of graphene, but also due to its high active density for the oxygen electrode reaction with efficient mass and electron transports. In this work, we try to electronically tailor 3D nitrogen-doped graphene (NG) using alumina (Al), and obtain the flower-like structure with a high Brunauer-Emmett-Teller (BET) surface area and abundant active sites, as a result, pure cobalt nanoparticles are easily confined. Physical characterizations confirm that this natural tuning of graphene by Al causes the increasing of surface defects, as a result, the physicochemical stability of Al and graphene is improved, and vice versa, consequently, the co-modification of Al and Co induce outstanding oxygen reduction reaction (ORR) performance including distinct onset potential, large diffusion limiting current density, kinetic current density and good stability, which are comparable with those of 20 wt% Pt/C in both alkaline and acidic media; in addition, the fabricated composite also delivers prior oxygen evolution reaction activity, superior to the benchmark RuO2. This hybrid herein exhibits a combined ORR and OER potential gap of 0.745 V, rivaling state-of-the-art bifunctional oxygen electrode catalysts.

  16. Bile acids and lipids in isolated rat hepatocytes. II. Source of cholesterol used for bile acid formation, estimated by incorporation of tritium from tritiated water, and by the effect of ML-236B

    NARCIS (Netherlands)

    Kempen, H.J.; Vos Van Holstein, M.; Lange, J.de

    1983-01-01

    Chemicals/CAS: cholesterol, 57-88-5; cholic acid, 32500-01-9, 361-09-1, 81-25-4; colestyramine, 11041-12-6, 58391-37-0; compactin, 73573-88-3; lipid, 66455-18-3; tritium oxide, 14940-65-9; Bile Acids and Salts; Cholesterol, 57-88-5; Cholestyramine, 11041-12-6; compactin, 73573-88-3; Lipids;

  17. In vitro model of infected stratum corneum for the efficacy evaluation of poloxamer 407-based formulations of ciclopirox olamine against Trichophyton rubrum as well as differential scanning calorimetry and stability studies.

    Science.gov (United States)

    Täuber, Anja; Müller-Goymann, Christel C

    2015-10-15

    Superficial fungal skin infections are a common disease and concern 20-25% of the world's population with the dermatophyte Trichophyton rubrum being the main trigger. Due to autoinoculation, fungal skin infections of the feet (tinea pedis) often occur simultaneously with fungal nail infections (onychomycosis). Therefore, the overall objective was the development and characterisation of poloxamer 407-based formulations with the antimycotic active ingredient ciclopirox olamine (CPX) for simultaneous antifungal therapy. The formulations consisted of poloxamer 407, water, isopropyl alcohol, propylene glycol and medium chain triglycerides in given ratios. The in vitro antifungal efficacy against T. rubrum was tested in a novel in vitro model of infected stratum corneum in comparison to a marketed semi-solid formulation containing 1% (w/w) ciclopirox olamine and a marketed nail lacquer containing 8% ciclopirox. Several liquid poloxamer 407-based formulations with only 1% CPX completely inhibited fungal growth after 6 days of incubation, whereas the marketed semi-solid formulation did not inhibit fungal growth. Differential scanning calorimetry studies revealing the interaction between the formulations and the SC showed that increasing isopropyl alcohol/propylene glycol concentrations as well as increasing CPX concentrations caused increasing endothermic transition shifts. Moreover, stability studies at 30 °C exhibited only a slight decrease of the CPX amount after 12 months of storage. Each formulation contained >90% of the initial CPX concentration after termination of the stability studies.

  18. Conversion of Dimethyl Ether to Branched Hydrocarbons Over Cu/BEA: the Roles of Lewis Acidic and Metallic Sites in H2 Incorporation

    Energy Technology Data Exchange (ETDEWEB)

    Hensley, Jesse E.; Schaidle, Joshua A.; Ruddy, Daniel A.; Cheah, Singfoong; Habas, Susan E.; Pan, Ming; Zhang, Guanghui; Miller, Jeffrey T.

    2017-04-26

    Conversion of biomass to fuels remains as one of the most promising approach to support our energy needs. It has been previously shown that the gasification of non-edible cellulosic biomass can be used to derive fuels like methanol and dimethyl ether (DME). However, the use of methanol and DME is limited due to the fact that they have low energy densities, poor lubricity and lower viscosity when compared to long-chain hydrocarbons. Increasing the blending percentage can also lead to undesired amounts of oxygenated molecules in the transportation fuel infrastructure, which restrict their applicability as jet or diesel fuels. Consequently, the petroleum-derived hydrocarbons remain as the main constituent of the middle-distillate based fuels. One way to increase the share of biofuels in middle-distillates is to use methanol/DME as building blocks for producing renewable, energy-dense hydrocarbons. One way to achieve this is by catalytically converting the DME and methanol to light olefins, followed by oligomerization to higher molecular weight premium alkanes, which can directly be used as kerosene/diesel fuels. Here, we report the catalytic dimerization of biomass-derived deoxygenated olefins into transportation fuel-range hydrocarbons under liquid-phase stirred-batch conditions. Specifically, the effect of operating conditions, such as reaction temperature, solvent-type, reaction duration and olefin-structure, on the conversion, selectivity and kinetics of dimerization of triptene (2,3,3-trimethyl-1-butene) were investigated. Triptene, as previously reported, is one of the major products of DME-homologation reaction over a BEA zeolite4. We show that triptene can be converted to high quality middle-distillates using a commercially available ion-exchange acid resin, Amberlyst-35 (dry) by the process of catalytic dimerization.

  19. A free-standing, sheet-shaped, "hydrophobic" biomaterial containing polymeric micelles formed from poly(ethylene glycol)-poly(lactic acid) block copolymer for possible incorporation/release of "hydrophilic" compounds.

    Science.gov (United States)

    Moroishi, Hitomi; Yoshida, Chikara; Murakami, Yoshihiko

    2013-02-01

    Sheet-shaped materials with a large contact area relative to the drug targeting site lead to advantages over conventional particle-shaped drug carriers and have several advantages for their biomedical applications. The present study proposes a methodology for preparing a novel sheet-shaped "hydrophobic" and biocompatible biomaterial in which polymeric micelles are uniformly dispersed for the incorporation of "hydrophilic" compounds into the sheet. The methoxy-terminated poly(ethylene glycol)-block-poly(lactic acid) block copolymer (CH(3)O-PEG-b-PLA) was successfully synthesized by means of the anionic ring-opening polymerization of both ethylene oxide and dl-lactide. CH(3)O-PEG-b-PLA was self-assembled and formed stable micelle-like w/o emulsion with a hydrophilic inner core in organic solvents. A sheet-shaped material containing a hydrophilic inner space for incorporating hydrophilic compounds was obtained by spin-coating both the micelle solution and a sheet-forming polymer. Fluorescent images of the sheet proved that polymeric micelles providing hydrophilic spaces were uniformly dispersed in the hydrophobic sheet. The facile technique presented in this paper can be a tool for fabricating sheet-shaped biomaterials that have a hydrophilic inner core and, consequently, that are suitable for the sustained release of hydrophilic compounds.

  20. Effects of butter high in ruminant trans and monounsaturated fatty acids on lipoproteins, incorporation of fatty acids into lipid classes, plasma C-reactive protein, oxidative stress, hemostatic variables, and insulin in healthy young men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Raff, M.; Basu, S.

    2006-01-01

    the effect of butter with a naturally high content of vaccenic acid and a concomitantly higher content of monounsaturated FAs on classic and novel risk markers of IHD. Design: In a double-blind, randomized, 5-wk, parallel intervention study, 42 healthy young men were given 115 g fat/d from test butter...... that was high in vaccenic acid (3.6 g vaccenic acid/d) or a control butter with a low content of vaccenic acid. Blood and urine samples were collected before and after the intervention. Results: The intake of the vaccenic acid-rich diet resulted in 6% and 9% lower total cholesterol and plasma HDL......-cholesterol concentrations, respectively, than did the intake of the control diet (P = 0.05 and 0.002, respectively), whereas the ratio of total to HDL cholesterol did not differ significantly between the groups. The FA composition of lipid classes reflected the FAs' proportion of the test butter. No other differences were...

  1. Incorporating Novel Mobile Health Technologies Into Management of Knee Osteoarthritis in Patients Treated With Intra-Articular Hyaluronic Acid: Rationale and Protocol of a Randomized Controlled Trial

    Science.gov (United States)

    Skrepnik, Nebojsa; Toselli, Richard M; Leroy, Bruno

    2016-01-01

    Background Osteoarthritis (OA) of the knee is one of the leading causes of disability in the United States. One relatively new strategy that could be helpful in the management of OA is the use of mHealth technologies, as they can be used to increase physical activity and promote exercise, which are key components of knee OA management. Objective Currently, no published data on the use of a mHealth approach to comprehensively monitor physical activity in patients with OA are available, and similarly, no data on whether mHealth technologies can impact outcomes are available. Our objective is to evaluate the effectiveness of mHealth technology as part of a tailored, comprehensive management strategy for patients with knee OA. Methods The study will assess the impact of a smartphone app that integrates data from a wearable activity monitor (thereby both encouraging changes in mobility as well as tracking them) combined with education about the benefits of walking on patient mobility. The results from the intervention group will be compared with data from a control group of individuals who are given the same Arthritis Foundation literature regarding the benefits of walking and wearable activity monitors but who do not have access to the data from those monitors. Activity monitors will capture step count estimates and will compare those with patients’ step goals, calories burned, and distance walked. Patients using the novel smartphone app will be able to enter information on their daily pain, mood, and sleep quality. The relationships among activity and pain, activity and mood, and sleep will be assessed, as will patient satisfaction with and adherence to the mobile app. Results We present information on an upcoming trial that will prospectively assess the ability of a mobile app to improve mobility for knee OA patients who are treated with intra-articular hyaluronic acid. Conclusions We anticipate the results of this study will support the concept that m

  2. PLGA/poloxamer nanoparticles loaded with EPAS1 siRNA for the treatment of pancreatic cancer in vitro and in vivo.

    Science.gov (United States)

    Pan, Xinting; Zhu, Qingyun; Sun, Yunbo; Li, Liandi; Zhu, Yunpeng; Zhao, Zhihui; Zuo, Jianxin; Fang, Wei; Li, Kun

    2015-04-01

    Endothelial PAS domain protein 1 (EPAS1) is a hypoxia-inducible protein that contributes to tumor progression. Hypoxia is involved in tumor aggressiveness and resistance to chemotherapy and ionizing radiation. In this study, we aimed to assess the effects of EPAS1 silencing using polyethylenimine-poly(lactide-coglycolide) (PLGA)/poloxamer nanoparticles loaded with EPAS1 siRNA on BxPC-3 pancreatic cancer cells and in a mouse model of ectopic pancreatic cancer. PLGA/poloxamer nanoparticles loaded with EPAS1 siRNA or scramble siRNA were prepared using the emulsion/solvent evaporation method. BxPC-3 pancreatic cancer cells were cultured under hypoxic conditions and treated with or without the nanoparticles. MTT and apoptosis assays were then performed. A xenograft nude mouse model of pancreatic cancer was established and the mice were treated with or without the nanoparticles. The mRNA and protein expression levels of EPAS1 in the tumor tissues were determined by semi-quantitative RT-PCR and western blot analysis, respectively. Vascular endothelial growth factor (VEGF) and tumor microvessel density indicated by CD34 were determined by immunohistochemistry. The in vitro release of EPAS1 siRNA from the nanoparticles exerted a sustained-release effect. EPAS1 siRNA nanoparticles inhibited BxPC-3 cell proliferation, and induced cell apoptosis under hypoxic conditions, compared with the nanoparticles loaded with scramble siRNA (all Pnanoparticles loaded with EPAS1 siRNA. The pancreatic tumors of the mice injected with nanoparticles loaded with EPAS1 siRNA were significantly smaller in size and had a lower number of microvessels and a percentage of VEGF-positive cells compared with those of the mice injected with the nanoparticles loaded with scramble siRNA (all Pnanoparticles loaded with EPAS1 siRNA inhibit pancreatic cancer cell proliferation, induce cell apoptosis under hypoxic conditions and significantly inhibit the formation of microvessels and tumor growth in vivo.

  3. Correção da acidez do solo em função de modos de incorporação de calcário Correction of soil acidity in function of lime incorporation manners

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Weirich Neto

    2000-04-01

    Full Text Available A solubilização do calcário no solo, sem o que não ocorre neutralização da acidez, demanda tempo e exige incorporação para aumentar o contato entre o corretivo e os colóides do solo. Com o objetivo de avaliar a correção da acidez do solo em função de diferentes modos de incorporação de calcário, foi conduzido um experimento, no ano agrícola 1993/94, em um Latossolo vermelho-escuro, distrófico, de campo nativo, do município de Ponta Grossa (PR. O delineamento experimental empregado foi o de blocos ao acaso, em parcelas subdivididas, com três repetições. Os tratamentos foram constituídos por cinco modos de incorporação: arado de discos mais duas gradagens, grade aradora mais duas gradagens, enxada rotativa, arado escarificador mais duas gradagens e distribuição na superfície sem incorporação, e por quatro doses de calcário dolomítico: 0, 2,8, 6,6 e 10,3 t ha-1, visando a elevar a saturação por bases do solo a 30, 60 e 90%. A planta teste utilizada foi o milho. Verificou-se que o modo de incorporação do corretivo no solo afeta a sua eficiência em relação à profundidade no perfil, na qual há neutralização da acidez. Houve elevação da saturação por bases do solo até a camada de 20cm, 15cm e 10cm, respectivamente, para os seguintes modos de incorporação: enxada rotativa, arado de discos ou grade aradora e arado escarificador ou calcário distribuído na superfície sem incorporação. Os valores de saturação por bases desejados não foram alcançados, três meses após a calagem, independente do modo de incorporação de calcário.The solubilization of lime in soil, without which the acidity neutralization does not occur, demands time and requires incorporation for increasing the contact between lime and soil coloides. In order to study the correction of soil acidity in function of lime incorporation manners, a field experiment was carried out, in Ponta Grossa, State of Paraná, Brazil, in a

  4. Thermo-sensitive composite hydrogels based on poloxamer 407 and alginate and their therapeutic effect in embolization in rabbit VX2 liver tumors.

    Science.gov (United States)

    Huang, Lili; Shen, Ming; Li, Rongxin; Zhang, Xiangyu; Sun, Ying; Gao, Pei; Fu, Hao; Liu, Hongqiang; He, Yang; Du, Yuqing; Cao, Jun; Duan, Yourong

    2016-11-08

    Interventional embolization therapy is an effective, most widely used method for inoperable liver tumors. Blood-vessel-embolic agents were essential in transarterial embolization (TAE). In this work, thermo-sensitive composite hydrogels based on poloxamer 407, sodium alginate, hydroxymethyl cellulose and iodixanol (PSHI), together with Ca2+ (PSHI-Ca2+) were prepared as liquid embolic agents for TAE therapy to liver cancer. With increasing temperature, PSHI exhibited two phase states: a flowing sol and a shrunken gel. Rheology tests showed good fluidity and excellent viscoelastic behavior with a gelation temperature (GT) of 26.5°C. The studies of erosion indicated that PSHI had calcium ion-related erosion characteristics and showed a slow erosion rate in an aqueous environment. When incubated with L929 cells, the thermo-sensitive composite hydrogels had low cytotoxicity in vitro. The results of analyzing the digital subtraction angiography and computed tomography images obtained from in vitro and in vivo assays indicated a good embolic effect in the renal arteries of normal rabbits. Angiography and histological studies on VX2 tumor-bearing rabbits indicated that PSHI-Ca2+ successfully occluded the tumors, including the peripheral vessels. In conclusion, PSHI-Ca2+ was a promising embolic agent for transarterial embolization therapy.

  5. Evaluation of the methylene blue addition in binary polymeric systems composed by poloxamer 407 and Carbopol 934P using quality by design: rheological, textural, and mucoadhesive analysis.

    Science.gov (United States)

    Junqueira, Mariana Volpato; Borghi-Pangoni, Fernanda Belincanta; Ferreira, Sabrina Barbosa de Souza; Bruschi, Marcos Luciano

    2016-12-01

    This study describes the investigation about the physicochemical behavior of methylene blue (Mb) addition to systems containing poloxamer 407 (Polox), Carbopol 934P (Carb), intended to be locally used by photodynamic therapy. A factorial design 2(3) (plus center point) was used to analyze the rheological, mucoadhesive and textural properties of the preparations. Systems containing the lower concentrations of Polox (15 and 17.5%, w/w) exhibited pseudoplastic flow and low degrees of rheopexy. On the other hand, at higher Polox concentration (20%, w/w) the systems display plastic flow and thixotropy. Carb and Mb exhibited a negative influence for the consistency and flow behavior index, due to the interaction between them. For most of the formulations, the increase of Polox and Mb content significantly increased storage modulus, loss modulus and dynamic viscosity. The systems display a sol-gel transition temperature, existing as a liquid at room temperature and gel at 29-37 °C. Increasing the temperature and the polymer concentration, the compressional properties of systems significantly increased. The mucoadhesion was noted to all formulations, except to systems composed by 15% (w/w) of Polox. The analyses enabled to understand and predict the performance of formulations and the polymer-Mb interactions, tailoring to the suit systems (Polox/Carb/Mb): 17.5/0.50/0.20 and 20/0.15/0.25.

  6. Thermo-sensitive composite hydrogels based on poloxamer 407 and alginate and their therapeutic effect in embolization in rabbit VX2 liver tumors

    Science.gov (United States)

    Huang, Lili; Shen, Ming; Li, Rongxin; Zhang, Xiangyu; Sun, Ying; Gao, Pei; Fu, Hao; Liu, Hongqiang; He, Yang; Du, Yuqing; Cao, Jun; Duan, Yourong

    2016-01-01

    Interventional embolization therapy is an effective, most widely used method for inoperable liver tumors. Blood-vessel-embolic agents were essential in transarterial embolization (TAE). In this work, thermo-sensitive composite hydrogels based on poloxamer 407, sodium alginate, hydroxymethyl cellulose and iodixanol (PSHI), together with Ca2+ (PSHI-Ca2+) were prepared as liquid embolic agents for TAE therapy to liver cancer. With increasing temperature, PSHI exhibited two phase states: a flowing sol and a shrunken gel. Rheology tests showed good fluidity and excellent viscoelastic behavior with a gelation temperature (GT) of 26.5°C. The studies of erosion indicated that PSHI had calcium ion-related erosion characteristics and showed a slow erosion rate in an aqueous environment. When incubated with L929 cells, the thermo-sensitive composite hydrogels had low cytotoxicity in vitro. The results of analyzing the digital subtraction angiography and computed tomography images obtained from in vitro and in vivo assays indicated a good embolic effect in the renal arteries of normal rabbits. Angiography and histological studies on VX2 tumor-bearing rabbits indicated that PSHI-Ca2+ successfully occluded the tumors, including the peripheral vessels. In conclusion, PSHI-Ca2+ was a promising embolic agent for transarterial embolization therapy. PMID:27602579

  7. Preferential Incorporation of Azelaic Acid Units into the Crystalline Phase of the Copoly(Alkylene Dicarboxylate Derived from 1,9-Nonanediol and an Equimolar Mixture of Pimelic and Azelaic Acids

    Directory of Open Access Journals (Sweden)

    Angélica Díaz

    2015-09-01

    Full Text Available The crystalline structure of two biodegradable odd-odd polyesters (i.e., poly(nonamethylene pimelate (PES 9,7 and poly(nonamethylene azelate (PES 9,9 was investigated by means of electron and X-ray diffraction of single crystals and oriented fibers, respectively. Truncated rhombic crystals were obtained with an aspect ratio that was strongly depended on the supercooling degree. The crystalline structure of both homopolyesters was defined by an orthorhombic P21ab space group and a large unit cell containing four molecular segments with an all-trans conformation. Nevertheless, the structure in the chain axis projection was equivalent to a simpler cell containing only two segments. Crystalline lamellae were effectively degraded by lipases, starting the enzymatic attack on the lamellar surfaces. The random copolymer constituted by an equimolar amount of pimelate and azelate units (COPES 9,7/9 crystallized according to regular lamellae with a similar molecular arrangement in the chain axis projection. The structure of this copolymer was preferably conditioned by the azelate component as could be deduced from both, diffraction and spectroscopic data. Analysis of small angle X-ray scattering patterns pointed out that less crystalline lamellae with higher amorphous thickness had developed in the copolymer. This feature was interpreted as a consequence of the preferential incorporation of pimelate comonomer units in the folding surface.

  8. 硼酸抑制纸片扩散试验检测肺炎克雷伯菌中的KPC%Disk tests incorporating boracic acid inhibitor to detect KPC in Klebsiella pneumoniae

    Institute of Scientific and Technical Information of China (English)

    严育忠; 胡付品; 孙康德; 范惠清; 陆燕春; 华静

    2012-01-01

    目的 评估利用硼酸的纸片扩散试验检测肺炎克雷伯菌中肺炎克雷伯菌碳青霉烯酶(KPC)的效能.方法 收集经基因鉴定非重复的36株产KPC肺炎克雷伯菌株;采用琼脂稀释法测定所有菌株对亚胺培南、美罗培南和厄他培南的最低抑菌浓度(MIC)值;聚合酶链反应(PCR)和DNA测序鉴定β-内酰胺酶基因型;使用标准和超过标准的2种测试菌量进行改良Hodge试验(MHT)以检测碳青霉烯酶表型;利用8种抗菌药物纸片含或不含硼酸抑制剂的纸片扩散试验检测KPC表型,以两者抑菌圈直径差值≥5 mm判定阳性结果.结果 所有36株产KPC菌株至少对1种碳青霉烯类药物耐药.MHT检测碳青霉烯酶的敏感性和特异性为97.2%和91.0%,增加菌量后的敏感性和特异性为100.0%和87.0%.利用硼酸联合头孢吡肟、亚胺培南或美罗培南的纸片扩散试验检测肺炎克雷伯菌产KPC表型,敏感性和特异性均达到100.0%.结论 硼酸联合头孢吡肟、亚胺培南或美罗培南的纸片扩散试验能检测出KPC表型,而且该方法操作简单、结果易读.%Objective To evaluate the disk tests incorporating boracic acid inhibitor for the detection of Klebsiella pneumoniae carbopenem ( KPC )-producing Klebsiella pneumoniae isolates. Methods A total of 36 genetically unrelated KPC-producing Klebsiella pneumoniae isolates were determined. The minimum inhibitory concentrations ( MIC) of imipenem,meropenem and ertapenem were determined by agar dilution method . Polymerase chain reaction (PCR) and DNA sequencing were used for the identification of beta 4actamase genotypes. The modified Hodge test (MHT) ,using both standard and high inoculum of test organisms ,was performed to detect carbopenem phenotype . The disk tests consisting of 8 antibiotics with and without boracic acid inhibitor were designed to detect KPC phenotype ,and the diameter ≥5 mm augmentation of inhibition zone was considered a positive result . Results

  9. Poloxamer-based binary hydrogels for delivering tramadol hydrochloride: sol-gel transition studies, dissolution-release kinetics, in vitro toxicity, and pharmacological evaluation

    Science.gov (United States)

    dos Santos, Ana Claudia Mendonça; Akkari, Alessandra Cristina Santos; Ferreira, Iasmin Rosanne Silva; Maruyama, Cintia Rodrigues; Pascoli, Monica; Guilherme, Viviane Aparecida; de Paula, Eneida; Fraceto, Leonardo Fernandes; de Lima, Renata; Melo, Patrícia da Silva; de Araujo, Daniele Ribeiro

    2015-01-01

    In this work, poloxamer (PL)-based binary hydrogels, composed of PL 407 and PL 188, were studied with regard to the physicochemical aspects of sol-gel transition and pharmaceutical formulation issues such as dissolution-release profiles. In particular, we evaluated the cytotoxicity, genotoxicity, and in vivo pharmacological performance of PL 407 and PL 407–PL 188 hydrogels containing tramadol (TR) to analyze its potential treatment of acute pain. Drug–micelle interaction studies showed the formation of PL 407–PL 188 binary systems and the drug partitioning into the micelles. Characterization of the sol-gel transition phase showed an increase on enthalpy variation values that were induced by the presence of TR hydrochloride within the PL 407 or PL 407–PL 188 systems. Hydrogel dissolution occurred rapidly, with approximately 30%–45% of the gel dissolved, reaching ~80%–90% up to 24 hours. For in vitro release assays, formulations followed the diffusion Higuchi model and lower Krel values were observed for PL 407 (20%, Krel =112.9±10.6 μg·h−1/2) and its binary systems PL 407–PL 188 (25%–5% and 25%–10%, Krel =80.8±6.1 and 103.4±8.3 μg·h−1/2, respectively) in relation to TR solution (Krel =417.9±47.5 μg·h−1/2, P72 hours) pointed to PL-based hydrogels as a potential treatment, by subcutaneous injection, for acute pain. PMID:25848258

  10. Sol-Gel Synthesis and Antioxidant Properties of Yttrium Oxide Nanocrystallites Incorporating P-123

    Directory of Open Access Journals (Sweden)

    Rebeca Mellado-Vázquez

    2014-09-01

    Full Text Available Yttrium oxide (Y2O3 nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems were heat-treated at temperatures from 700 °C to 900 °C. Systems at 900 °C were prepared in the presence and absence of P-123 using different molar ratios (P-123:Y = 1:1 and 2:1. Fourier transform infrared spectroscopy (FTIR results revealed a characteristic absorption band of Y–O vibrations typical of Y2O3 matrix. The structural phase was analyzed by X-ray diffraction (XRD, showing the characteristic cubic phase in all systems. The diffraction peak that presented the major intensity corresponded to the sample prepared from yttrium chloride incorporating P-123 in a molar ratio of P-123:Y = 2:1 at 900 °C. Crystallites sizes were determined by Scherrer equation as between 21 nm and 32 nm. Antioxidant properties were estimated by 2,2-diphenyl-1-picrylhydrazyl (DPPH• assays; the results are discussed.

  11. Comparative Incorporation of PNA into DNA Nanostructures

    Directory of Open Access Journals (Sweden)

    Ronnie O. Pedersen

    2015-09-01

    Full Text Available DNA has shown great promise as a building material for self-assembling nanoscale structures. To further develop the potential of this technology, more methods are needed for functionalizing DNA-based nanostructures to increase their chemical diversity. Peptide nucleic acid (PNA holds great promise for realizing this goal, as it conveniently allows for inclusion of both amino acids and peptides in nucleic acid-based structures. In this work, we explored incorporation of a positively charged PNA within DNA nanostructures. We investigated the efficiency of annealing a lysine-containing PNA probe with complementary, single-stranded DNA sequences within nanostructures, as well as the efficiency of duplex invasion and its dependence on salt concentration. Our results show that PNA allows for toehold-free strand displacement and that incorporation yield depends critically on binding site geometry. These results provide guidance for the design of PNA binding sites on nucleic acid nanostructures with an eye towards optimizing fabrication yield.

  12. Bilateral lesions of suprachiasmatic nuclei affect circadian rhythms in (/sup 3/H)-thymidine incorporation into deoxyribonucleic acid in mouse intestinal tract, mitotic index of corneal epithelium, and serum corticosterone

    Energy Technology Data Exchange (ETDEWEB)

    Scheving, L.E.; Tsai, T.H.; Powell, E.W.; Pasley, J.N.; Halberg, F.; Dunn, J.

    1983-03-01

    Investigations into the role of the suprachiasmatic nuclei (SCN) in the coordination of circadian rhythms have presented differing results. Several reports have shown that ablation of the suprachiasmatic nuclei (SCNA) alters the phase and amplitude of rhythms but does not abolish them. The present study investigates the effect of SCNA on the rhythms in cell proliferation in various regions of the intestinal tract as measured by the incorporation of (/sup 3/H)-thymidine into deoxyribonucleic acid, in the mitotic activity of the corneal epithelium, and in serum corticosterone levels. The study involved mice with verified lesions of the SCN (six to 13 mice per time point) and control groups of both sham-operated and unoperated mice (seven of each per time point). The mice were killed in groups that represented seven time points over a single 24 hr span (3 hr intervals with the 0800 hr sampled both at start and end of the series). The tissues examined were the tongue, esophagus, gastric stomach, and colon for DNA synthesis, the corneal epithelium for mitotic index, and blood serum for corticosterone level. The most consistent result of SCNA was a phase advance in the rhythms in cell proliferation in the tongue, esophagus, gastric stomach, colon, and corneal epithelium. A reduction in rhythm amplitude occurred in the tongue, esophagus, and corneal epithelium; however, there was an amplitude increase for the stomach, colon, and serum corticosterone. The mesor (rhythm-adjusted mean) was increased by SCNA in all tissues except the corneal epithelium. These findings further support the role of the suprachiasmatic nuclear area in the control of rhythms in cell proliferation and corticosterone production, by acting as a ''phase-resetter'' and as a modulator of rhythm amplitude.

  13. Incorporating Feminist Standpoint Theory

    DEFF Research Database (Denmark)

    Ahlström, Kristoffer

    2005-01-01

    As has been noted by Alvin Goldman, there are some very interesting similarities between his Veritistic Social Epistemology (VSE) and Sandra Harding’s Feminist Standpoint Theory (FST). In the present paper, it is argued that these similarities are so significant as to motivate an incorporation...

  14. Differentiating leucine incorporation of

    NARCIS (Netherlands)

    Yokokawa, T.; Sintes, E.; de Corte, D.; Olbrich, K.; Herndl, G.J.

    2012-01-01

    The abundance (based on catalyzed reporter deposition-fluorescence in situ hybrid ization, CARD-FISH) and leucine incorporation rates of Archaea and Bacteria were determined throughout the water column in the eastern Atlantic. Bacteria dominated throughout the water column, although their contributi

  15. Poloxamer-based binary hydrogels for delivering tramadol hydrochloride: sol-gel transition studies, dissolution-release kinetics, in vitro toxicity, and pharmacological evaluation

    Directory of Open Access Journals (Sweden)

    dos Santos ACM

    2015-03-01

    Full Text Available Ana Claudia Mendonça dos Santos,1 Alessandra Cristina Santos Akkari,1 Iasmin Rosanne Silva Ferreira,2 Cintia Rodrigues Maruyama,3 Monica Pascoli,3 Viviane Aparecida Guilherme,4 Eneida de Paula,4 Leonardo Fernandes Fraceto,5 Renata de Lima,3 Patrícia da Silva Melo,2 Daniele Ribeiro de Araujo1 1Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, 2Faculdades Integradas Metropolitanas de Campinas, Campinas, 3Departamento de Biotecnologia, Universidade de Sorocaba, Sorocaba, 4Departamento de Bioquímica, Universidade Estadual de Campinas, Campinas, 5Departamento de Engenharia Ambiental, Universidade Estadual ‘Júlio de Mesquita Filho’, Sorocaba, São Paulo, Brazil Abstract: In this work, poloxamer (PL-based binary hydrogels, composed of PL 407 and PL 188, were studied with regard to the physicochemical aspects of sol-gel transition and pharmaceutical formulation issues such as dissolution-release profiles. In particular, we evaluated the cytotoxicity, genotoxicity, and in vivo pharmacological performance of PL 407 and PL 407–PL 188 hydrogels containing tramadol (TR to analyze its potential treatment of acute pain. Drug–micelle interaction studies showed the formation of PL 407–PL 188 binary systems and the drug partitioning into the micelles. Characterization of the sol-gel transition phase showed an increase on enthalpy variation values that were induced by the presence of TR hydrochloride within the PL 407 or PL 407–PL 188 systems. Hydrogel dissolution occurred rapidly, with approximately 30%–45% of the gel dissolved, reaching ~80%–90% up to 24 hours. For in vitro release assays, formulations followed the diffusion Higuchi model and lower Krel values were observed for PL 407 (20%, Krel =112.9±10.6 µg·h-1/2 and its binary systems PL 407–PL 188 (25%–5% and 25%–10%, Krel =80.8±6.1 and 103.4±8.3 µg·h-1/2, respectively in relation to TR solution (Krel =417.9±47.5 µg·h-1/2, P<0.001. In

  16. Effects of a Lidocaine-Loaded Poloxamer/Alginate/CaCl2 Mixture on Postoperative Pain and Adhesion in a Rat Model of Incisional Pain.

    Science.gov (United States)

    Choi, Geun Joo; Kang, Hyun; Hong, Min Eui; Shin, Hwa Yong; Baek, Chong Wha; Jung, Yong Hun; Lee, Younsuk; Kim, Jeong Wook; Park, I L Kyu; Cho, Wan Jin

    2017-07-01

    Pain and adhesion are problematic issues after surgery. Lidocaine has analgesics and anti-inflammatory properties, and poloxamer/alginate/CaCl2 (PACM) is a known antiadhesive agent. We hypothesized that the novel combination of lidocaine as chemical barrier and PACM as physical barrier would be beneficial for both postoperative pain and adhesion. The purpose of this study was to investigate the effects of lidocaine-loaded PACM in a rat model of incisional pain. Primary outcome was to evaluate between-group differences for the mechanical withdrawal threshold (MWT) measured by von Frey filament in various concentrations of lidocaine-loaded PACM applied, PACM applied, and sham-operated groups. Male Sprague-Dawley rats were used for the postoperative pain model. After plantar incision and adhesion formation, 0.5%, 1%, 2%, and 4% lidocaine-loaded PACM, PACM only, nothing, and 4% lidocaine only were applied at the incision site in groups PL0.5, PL1, PL2, PL4, P, S, and L4, respectively. MWT using a von Frey filament and serum levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and high-sensitivity C-reactive protein were measured. Rats were euthanized 2 weeks after surgery, and inflammation and fibrosis were assessed with microscopy. Data were analyzed using the Kruskal-Wallis test, multivariate analysis of variance, and linear mixed-effect model. To compare MWT at each time point, analysis of variance with Bonferroni correction was used. Multivariate analysis of variance showed that 4% lidocaine-loaded PACM significantly raised the MWT up to 6 and 8 hours after surgery compared with lidocaine-unloaded groups S and P, respectively; 2% lidocaine-loaded PACM significantly increased the MWT at 4 hours after surgery compared with groups S and C. Linear mixed-effect model showed that the MWT (estimated difference in means [95% confidence interval]) was significantly increased in groups PL2 and PL4 (6.58 [2.52-10.63], P = .002; 11.46 [7.40-15.51], P lidocaine only

  17. Staphylococcus aureus Sortase A-Mediated Incorporation of Peptides: Effect of Peptide Modification on Incorporation.

    Directory of Open Access Journals (Sweden)

    Silvie Hansenová Maňásková

    Full Text Available The endogenous Staphylococcus aureus sortase A (SrtA transpeptidase covalently anchors cell wall-anchored (CWA proteins equipped with a specific recognition motif (LPXTG into the peptidoglycan layer of the staphylococcal cell wall. Previous in situ experiments have shown that SrtA is also able to incorporate exogenous, fluorescently labelled, synthetic substrates equipped with the LPXTG motif (K(FITCLPETG-amide into the bacterial cell wall, albeit at high concentrations of 500 μM to 1 mM. In the present study, we have evaluated the effect of substrate modification on the incorporation efficiency. This revealed that (i by elongation of LPETG-amide with a sequence of positively charged amino acids, derived from the C-terminal domain of physiological SrtA substrates, the incorporation efficiency was increased by 20-fold at 10 μM, 100 μM and 250 μM; (ii Substituting aspartic acid (E for methionine increased the incorporation of the resulting K(FITCLPMTG-amide approximately three times at all concentrations tested; (iii conjugation of the lipid II binding antibiotic vancomycin to K(FITCLPMTG-amide resulted in the same incorporation levels as K(FITCLPETG-amide, but much more efficient at an impressive 500-fold lower substrate concentration. These newly developed synthetic substrates can potentially find broad applications in for example the in situ imaging of bacteria; the incorporation of antibody recruiting moieties; the targeted delivery and covalent incorporation of antimicrobial compounds into the bacterial cell wall.

  18. Practical preparation procedures for docetaxel-loaded nanoparticles using polylactic acid-co-glycolic acid

    Directory of Open Access Journals (Sweden)

    Keum CG

    2011-10-01

    Full Text Available Chang-Gu Keum1*, Young-Wook Noh1*, Jong-Suep Baek1, Ji-Ho Lim1, Chan-Ju Hwang1, Young-Guk Na1, Sang-Chul Shin2, Cheong-Weon Cho11College of Pharmacy and Institute of Drug Research and Development, Chungnam National University, Gungdong, Yuseonggu, Daejeon, South Korea; 2College of Pharmacy, Chonnam National University, Yongbongdong, Buggu, Gwangju, South Korea *These authors contributed equally to this work Background: Nanoparticles fabricated from the biodegradable and biocompatible polymer, polylactic-co-glycolic acid (PLGA, are the most intensively investigated polymers for drug delivery systems. The objective of this study was to explore fully the development of a PLGA nanoparticle drug delivery system for alternative preparation of a commercial formulation. In our nanoparticle fabrication, our purpose was to compare various preparation parameters. Methods: Docetaxel-loaded PLGA nanoparticles were prepared by a single emulsion technique and solvent evaporation. The nanoparticles were characterized by various techniques, including scanning electron microscopy for surface morphology, dynamic light scattering for size and zeta potential, x-ray photoelectron spectroscopy for surface chemistry, and high-performance liquid chromatography for in vitro drug release kinetics. To obtain a smaller particle, 0.2% polyvinyl alcohol, 0.03% D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS, 2% Poloxamer 188, a five-minute sonication time, 130 W sonication power, evaporation with magnetic stirring, and centrifugation at 8000 rpm were selected. To increase encapsulation efficiency in the nanoparticles, certain factors were varied, ie, 2–5 minutes of sonication time, 70–130 W sonication power, and 5–25 mg drug loading. Results: A five-minute sonication time, 130 W sonication power, and a 10 mg drug loading amount were selected. Under these conditions, the nanoparticles reached over 90% encapsulation efficiency. Release kinetics showed that 20

  19. Selective incorporation of 5-hydroxytryptophan into proteins in mammalian cells

    Science.gov (United States)

    Zhang, Zhiwen; Alfonta, Lital; Schultz, Peter G

    2014-02-25

    This invention provides methods and compositions for incorporation of an unnatural amino acid into a peptide using an orthogonal aminoacyl tRNA synthetase/tRNA pair. In particular, an orthogonal pair is provided to incorporate 5-hydroxy-L-tryptophan in a position encoded by an opal mutation.

  20. Deuterium incorporation into Escherichia-coli proteins

    DEFF Research Database (Denmark)

    Lederer, H.; May, R. P.; Kjems, Jørgen

    1986-01-01

    Neutron small-angle scattering studies of single protein subunits in a protein-DNA complex require the adjustment of the neutron scattering-length densities of protein and DNA, which is attainable by specific deuteration of the protein. The neutron scattering densities of unlabelled DNA and DNA...... of the degree of deuteration and match point of any E. coli protein from the D2O content of the growth medium, taking the 2H incorporation into RNA polymerase amino acids to be representative for all amino acids in E. coli proteins. The small-angle scattering results, on which the calculation of the degree...

  1. Deuterium incorporation into Escherichia-coli proteins

    DEFF Research Database (Denmark)

    Lederer, H.; May, R. P.; Kjems, Jørgen;

    1986-01-01

    Neutron small-angle scattering studies of single protein subunits in a protein-DNA complex require the adjustment of the neutron scattering-length densities of protein and DNA, which is attainable by specific deuteration of the protein. The neutron scattering densities of unlabelled DNA and DNA...... of the degree of deuteration and match point of any E. coli protein from the D2O content of the growth medium, taking the 2H incorporation into RNA polymerase amino acids to be representative for all amino acids in E. coli proteins. The small-angle scattering results, on which the calculation of the degree...

  2. 泊洛沙姆固体分散体对辛伐他汀溶出特性的影响%Effect of poloxamer solid dispersion on the dissolution of simvastatin

    Institute of Scientific and Technical Information of China (English)

    彭霞; 何江梅; 黄兴亮; 吴瑾; 陈章宝

    2013-01-01

    目的 考察泊洛沙姆固体分散体对辛伐他汀体外溶出特性的影响.方法 采用溶剂-熔融法制备辛伐他汀-泊洛沙姆188固体分散体,并用差示扫描量热法(DSC)、X射线粉末衍射(X-RD)和红外光谱(FTIR)考察药物在固体分散体中的存在状态,并进行体外溶出度的研究.结果 药物以分子或无定形态均匀分散于载体中,药物的溶出度随载体比例的增加而增加.结论 制备的辛伐他汀-泊洛沙姆188固体分散体能明显提高辛伐他汀的溶出度.%Objective To study the effect of poloxamer solid dispersion on the in vitro dissolution of simvastatin. Method Poloxamer was used as the carrier materials to prepare simvastatin poloxamcr solid dispersion by melting methods and investigate the dissolution characteristics of different dispersion systems. Differential scanning calorimctry (DSC),X-ray diffraction(X-RD) and Fourier transform infrared spectroscopy(FTIR) methods were used to detect the dispersion state of simvastatin. Result The drug exists in crystallite or amorphous form in solid dispersion,and the dissolution rates of simvastatin increase with the increase of the weight ratio of drug and carrier. Conclusion Simvastatin solid dispersion can obviously improve the dissolution rate of simvastatin by using poloxamcr 188 as a carrier.

  3. Drug Diffusion Behavior of pH-Sensitive PMAA-co-poloxamer Hydrogels%药物在pH敏感聚甲基丙烯酸-poloxamer水凝胶中的扩散行为

    Institute of Scientific and Technical Information of China (English)

    徐晖; 丁平田; 赵会英; 郑俊民

    2001-01-01

    The pH-sensitive hydrogel networks comprising of MAA and poloxamer were synthesizedby free-radical solution polymerization. The gels exhibit pH-dependant solute diffusivity due to theformation or disruption of hydrogen bondings between MAA and EO unit in poloxamer molecules.The values of diffusion coefficients of dextromethorphan (DMP) and vitamin (Vb12) were found inrange from 10-7 to 10-6 cm2/s in uncomplexed hydrogels (pH 7.0) and from 10-11 to 10-8 cm2/s incomplexed hydrogels(pH 4.0) ,respectively. Solute diffusivity decreased as solute size increased. Themole ratio of EO unit to MAA unit is the main factor that affects equilibrium swelling, solute partitionand permeability characteristics of these hydrogels.%采用自由基溶液聚合方法制备甲基丙烯酸(MAA)和poloxamer的共聚物水凝胶,研究药物在此水凝胶中的扩散行为.由于MAA与poloxamer中乙氧基(EO)的氢键络合作用,水凝胶的溶胀和水凝胶中药物的扩散具有pH敏感性,络合状态水凝胶(pH为4.0)中氢溴酸右美沙芬和维生素B12的扩散系数在10-11~10-8 cm2/s之间,溶胀状态时(pH为7.0)为10-7~10-6cm2/s.EO与MAA的摩尔比是影响水凝胶平衡溶胀和药物在水凝胶中的分配与扩散性质的重要因素.

  4. Aniline incorporated silica nanobubbles

    Indian Academy of Sciences (India)

    M J Rosemary; V Suryanarayanan; Ian Maclaren; T Pradeep

    2006-09-01

    We report the synthesis of stearate functionalized nanobubbles of SiO2 with a few aniline molecules inside, represented as C6H5NH2@SiO2@stearate, exhibiting fluorescence with red-shifted emission. Stearic acid functionalization allows the materials to be handled just as free molecules, for dissolution, precipitation, storage etc. The methodology adopted involves adsorption of aniline on the surface of gold nanoparticles with subsequent growth of a silica shell through monolayers, followed by the selective removal of the metal core either using sodium cyanide or by a new reaction involving halocarbons. The material is stable and can be stored for extended periods without loss of fluorescence. Spectroscopic and voltammetric properties of the system were studied in order to understand the interaction of aniline with the shell as well as the monolayer, whilst transmission electron microscopy has been used to study the silica shell.

  5. Nepal CRS project incorporates.

    Science.gov (United States)

    1983-01-01

    The Nepal Contraceptive Retail Sales (CRS) Project, 5 years after lauching product sales in June 1978, incorporated as a private, nonprofit company under Nepalese management. The transition was finalized in August 1983. The Company will work through a cooperative agreement with USAID/Kathmandu to complement the national family planning goals as the program continues to provide comtraceptives through retail channels at subsidized prices. Company objectives include: increase contraceptive sales by at least 15% per year; make CRS cost effective and move towards self sufficiency; and explore the possibility of marketing noncontraceptive health products to improve primary health care. After only5 years the program can point to some impressive successes. The number of retial shops selling family planning products increased from 100 in 1978 to over 8000, extending CRS product availability to 66 of the country's 75 districts. Retail sales have climbed dramatically in the 5-year period, from Rs 46,817 in 1978 to Rs 271,039 in 1982. Sales in terms of couple year protection CYP) have grown to 24,451 CYP(1982), a 36% increase over 1980 CYP. Since the beginning of the CRS marketing program, total distribution of contraceptives--through both CRS and the Family Planning Maternal and Child Haelth (FP/MCH) Project--has been increasing. While the FP/MCH program remains the largest distributor,contribution of CRS Products is increasing, indicating that CRS is creating new product acceptors. CRS market share in 1982 was 43% for condoms and 16% for oral contraceptives (OCs). CRS markets 5 products which are subsidized in order to be affordable to consumers as well as attractive to sellers. The initial products launched in June 1978 were Gulaf standard dose OCs and Dhaal lubricated colored condoms. A less expensive lubricates, plain Suki-Dhaal condom was introduced in June 1980 in an attempt to reach poorer rural populations, but rural distribution costs are excessive and Suki

  6. Incorporation, plurality, and the incorporation of plurals: a dynamic approach

    NARCIS (Netherlands)

    de Swart, H.E.; Farkas, D. F.

    2004-01-01

    This paper deals with the semantic properties of incorporated nominals that are present at clausal syntax. Such nominals exhibit a complex cluster of semantic properties, ranging from argument structure, scope, and number to discourse transparency. We develop an analysis of incorporation in the fram

  7. 去甲斑蝥素-泊洛沙姆聚合物纳米胶束的制备及表征%Preparation and Characterization of Norepinephrine Cantharidin-Poloxamer Polymer Nano-Micelle

    Institute of Scientific and Technical Information of China (English)

    尹美珍; 杨子春; 包洋; 苷珺; 蔡江红

    2015-01-01

    为制备去甲斑蝥素-泊洛沙姆给药系统新制剂,采用薄膜水化法,以泊洛沙姆F127为载体,包载去甲斑蝥素,制备纳米聚合物载药胶束;高效液相色谱法测定胶束的包封率和载药量,动态光散射法测定胶束粒径,紫外分光光度仪以及红外分光光度仪测定并分析药物在胶束中的分布状态. 结果显示去甲斑蝥素被成功包载于聚合物胶束上,聚合物载药胶束的平均粒径为10. 3 nm,粒度分布较窄,包封率和载药量分别约为98%和4 . 67%. 因此,这种载药纳米粒制备工艺简单,粒径小,对疏水性药物有较高的包封率. 这为进一步制备靶向纳米载药胶束打下了基础,为包载其他疏水药物的聚合物胶束的制备提供实验依据.%To prepare a new form of norcantharidin-poloxamer nano-drug delivery systems,a thin-film hy-dration method was used,norcantharidin -loaded polymeric micelles with poloxamer F127 as a novel drug carrier was prepared. Eencapsulation ratio and drug-loading coeffieient,particle size,and drug distribution state of the polymeric micelles were examined by means of HPLC,dynamic light scattering,UV spectrum and FTIR spectrum respectively. The results showed that norcantharidin was successfully entrapped in the polymer micelles with encapsulation ratio of 98%. The drug-loaded polymeric micelles possessed narrow particle size distribution with average particle size of 10. 3 nm,and drug-loading coeffieient of 4. 67%. Therefore,this drug-loaded nanoparticles possess several advantages:simple preparation process, small particle size, and high encapsulation efficiency for hydrophobic drugs. This will set the stage for the further preparation of targe-ted nanoparticles,but also for the preparation of other drug-loaded polymeric micelles offer experimental ba-sis.

  8. Bismuth incorporation into gallium phosphide

    Energy Technology Data Exchange (ETDEWEB)

    Jena, Puru [Virginia Commonwealth Univ. (United States); Kandalam, Anil K. [West Chester Univ. of Pennsylvania (United States); Christian, Theresa M. [National Renewable Energy Lab. (United States); Beaton, Daniel A. [National Renewable Energy Lab. (United States); Mascarenhas, Angelo [National Renewable Energy Lab. (United States); Alberi, Kirstin [National Renewable Energy Lab. (United States)

    2016-12-21

    Gallium phosphide bismide (GaP1-xBix) epilayers with bismuth fractions from 0.9% to 3.2%, as calculated from lattice parameter measurements, were studied with Rutherford backscattering spectrometry (RBS) to directly measure bismuth incorporation. The total bismuth fractions found by RBS were higher than expected from the lattice parameter calculations. Furthermore, in one analyzed sample grown by molecular beam epitaxy at 300 degrees C, 55% of incorporated bismuth was found to occupy interstitial sites. We discuss implications of this high interstitial incorporation fraction and its possible relationship to x-ray diffraction and photoluminescence measurements of GaP0.99Bi0.01.

  9. Positional specificity of saturated and unsaturated fatty acids in phosphatidic acid from rat liver

    NARCIS (Netherlands)

    Possmayer, F.; Scherphof, G.L.; Dubbelman, T.M.A.R.; Golde, L.M.G. van; Deenen, L.L.M. van

    1969-01-01

    1. 1. The relative incorporation of a number of radioactive fatty acids into the different glycerolipids of rat liver microsomes has been investigated. 2. 2. Studies on the distribution of the radioactivity incorporated into phosphatidylcholine, phosphatidylethanolamine and phosphatidic acid showed

  10. Swelling and Drug Release Characteristics of Poly (methacrylic acid-co-poloxamer) hydrogels

    Institute of Scientific and Technical Information of China (English)

    XUHui; LINYan-nan; DINGPing-tian; TIANMei-juan; ZHENGJun-min

    2003-01-01

    Poly (methacrylie acid co-poloxamer) hydrogel networks were synthesized by free-radical solution polymerization, and the dynamic swelling and in vitro release properties of model drugs, dextromethorphan hydrobromide (DMP) and vitamin B12 (VB12) were studied. These gels exhibited pH-dependant swelling and sustained drug release properties, and the water uptake rate and drug release rate in neutral or basic media were higher than that in acidic media. The results showed that the water uptake followed non-Fickian or zero order process in neutral or basic media, and the release of model drugs from hydrogels of appropriate composition was of zero order kinetics over a period of several hours.

  11. Host thin films incorporating nanoparticles

    Science.gov (United States)

    Qureshi, Uzma

    The focus of this research project was the investigation of the functional properties of thin films that incorporate a secondary nanoparticulate phase. In particular to assess if the secondary nanoparticulate material enhanced a functional property of the coating on glass. In order to achieve this, new thin film deposition methods were developed, namely use of nanopowder precursors, an aerosol assisted transport technique and an aerosol into atmospheric pressure chemical vapour deposition system. Aerosol assisted chemical vapour deposition (AACVD) was used to deposit 8 series of thin films on glass. Five different nanoparticles silver, gold, ceria, tungsten oxide and zinc oxide were tested and shown to successfully deposit thin films incorporating nanoparticles within a host matrix. Silver nanoparticles were synthesised and doped within a titania film by AACVD. This improved solar control properties. A unique aerosol assisted chemical vapour deposition (AACVD) into atmospheric pressure chemical vapour deposition (APCVD) system was used to deposit films of Au nanoparticles and thin films of gold nanoparticles incorporated within a host titania matrix. Incorporation of high refractive index contrast metal oxide particles within a host film altered the film colour. The key goal was to test the potential of nanopowder forms and transfer the suspended nanopowder via an aerosol to a substrate in order to deposit a thin film. Discrete tungsten oxide nanoparticles or ceria nanoparticles within a titanium dioxide thin film enhanced the self-cleaning and photo-induced super-hydrophilicity. The nanopowder precursor study was extended by deposition of zinc oxide thin films incorporating Au nanoparticles and also ZnO films deposited from a ZnO nanopowder precursor. Incorporation of Au nanoparticles within a VO: host matrix improved the thermochromic response, optical and colour properties. Composite VC/TiC and Au nanoparticle/V02/Ti02 thin films displayed three useful

  12. 泊洛沙姆407诱发金黄地鼠脂质代谢紊乱模型及其初步机制%A dyslipidemia animal model induced by poloxamer 407 in golden hamsters and pilot study on the mechanism

    Institute of Scientific and Technical Information of China (English)

    刘泉; 刘率男; 李林忆; 陈致瑜; 雷蕾; 张宁; 申竹芳

    2011-01-01

    The aim of this study is to establish a simple and stable model like poloxamer 407 (P-407)-induced dyslipidemia of golden hamster model, and investigate the mechanism of lipid metabolism disturbance in this model. PPARa agonist and HMG-CoA reductase inhibitor were administrated to validate the efficacy on regulating lipid metabolism in the dyslipidemia golden hamster model. Six weeks male golden hamsters were chosen to inject P-407 intraperitoneally at a bolus dose of 300 mg·kg-1, an intermittent injection at a dose of 200 mg·kg-1 every 72 hours after the bolus. The results showed that P-407-induced golden hamster model characterized as increased serum triglyceride (TG), total cholesterol (TC), free cholesterol (free-CHO), cholesteryl ester (CE), free fatty acids (FFA) and apoB levels, and the hyperlipidemia state maintained at a stable level persistently. Meanwhile, augmented malondialdehyde (MDA) and nitric oxide (NO) level was observed. LCAT and SR-B Ⅰ mRNA levels in liver of model group were down-regulated (expression ratio is 0.426; 0.783), while HMG-CoA reductase mRNA level was up-regulated (expression ratio is 1.493) compared with those of the normal group. The serum cholesterol and triglyceride levels were significantly lower in P407-induced dyslipidemia hamster model afier treated with atorvastatin (Ato) at a dose of 50 mg·kg-1 or fenofibrate (Fen) at 100 mg·kg-1 for two weeks. These findings suggest that serum lipid distribution in dyslipidemia golden hamster is similar to that of human, and which may be relevant to the disturbance of the enzymes expression involved in lipid metabolism in liver. Results obtained from this study support the concept that dyslipidemia golden hamster may be an adequate animal model to evaluate the efficacy of lipid-lowering agents.%采用泊洛沙姆(poloxamer 407,P-407)诱导金黄地鼠形成脂质代谢紊乱实验动物模型,并对其脂质代谢紊乱机制进行初步探讨;同时评价该模型对两类市售

  13. Incorporating Argumentation through Forensic Science

    Science.gov (United States)

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Smetana, Lara K.

    2014-01-01

    This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students' development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock…

  14. Incorporating Argumentation through Forensic Science

    Science.gov (United States)

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Smetana, Lara K.

    2014-01-01

    This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students' development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock…

  15. Thermogelling hydrogels of cyclodextrin/poloxamer polypseudorotaxanes as aqueous-based nail lacquers: application to the delivery of triamcinolone acetonide and ciclopirox olamine.

    Science.gov (United States)

    Nogueiras-Nieto, Luis; Begoña Delgado-Charro, M; Otero-Espinar, Francisco J

    2013-04-01

    This work investigated the use of in situ gelling hydrogels based on polypseudorotaxanes of Pluronic F-127 and partially methylated β-cyclodextrin as aqueous nail lacquers. N-acetylcysteine and urea were incorporated as penetration enhancers. The formulations were tested for their ability to deliver ciclopirox and triamcinolone across human nail plate and bovine hoof. Simple aqueous solutions of the drugs with N-acetylcysteine provided measurable fluxes across hoof membranes but became quickly depleted of drug. Further, these solutions would have a short residence time upon nail application. Addition of Pluronic F-127 facilitated drug solubilization and provided the formulations with in situ gelling properties but drug entrapment into the micelles slowed down the delivery process. This was solved by addition of methylated β-cyclodextrin; the formulations retained the thermogelling properties, drug solubilization was further increased, and drug delivery was accelerated. The polymer chains compete with the drugs for the cyclodextrin cavity forming polypseudorotaxanes, which facilitated drug release. The permeability of both drugs was higher across bovine hoof than human nail. The new polypseudorotaxanes formulation delivered more ciclopirox across human nail than a marketed organic lacquer which supports the growing hypothesis that aqueous-based nail lacquers represent a superior formulation strategy in nail topical delivery. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Incorporating Spirituality in Primary Care.

    Science.gov (United States)

    Isaac, Kathleen S; Hay, Jennifer L; Lubetkin, Erica I

    2016-06-01

    Addressing cultural competency in health care involves recognizing the diverse characteristics of the patient population and understanding how they impact patient care. Spirituality is an aspect of cultural identity that has become increasingly recognized for its potential to impact health behaviors and healthcare decision-making. We consider the complex relationship between spirituality and health, exploring the role of spirituality in primary care, and consider the inclusion of spirituality in existing models of health promotion. We discuss the feasibility of incorporating spirituality into clinical practice, offering suggestions for physicians.

  17. VLDL hydrolysis by LPL activates PPAR-alpha through generation of unbound fatty acids.

    Science.gov (United States)

    Ruby, Maxwell A; Goldenson, Benjamin; Orasanu, Gabriela; Johnston, Thomas P; Plutzky, Jorge; Krauss, Ronald M

    2010-08-01

    Recent evidence suggests that lipoproteins serve as circulating reservoirs of peroxisomal proliferator activated receptor (PPAR) ligands that are accessible through lipolysis. The present study was conducted to determine the biochemical basis of PPAR-alpha activation by lipolysis products and their contribution to PPAR-alpha function in vivo. PPAR-alpha activation was measured in bovine aortic endothelial cells following treatment with human plasma, VLDL lipolysis products, or oleic acid. While plasma failed to activate PPAR-alpha, oleic acid performed similarly to VLDL lipolysis products. Therefore, fatty acids are likely to be the PPAR-alpha ligands generated by VLDL lipolysis. Indeed, unbound fatty acid concentration determined PPAR-alpha activation regardless of fatty acid source, with PPAR-alpha activation occurring only at unbound fatty acid concentrations that are unachievable under physiological conditions without lipase action. In mice, a synthetic lipase inhibitor (poloxamer-407) attenuated fasting-induced changes in expression of PPAR-alpha target genes. Apolipoprotein CIII (apoCIII), an endogenous inhibitor of lipoprotein and hepatic lipase, regulated access to the lipoprotein pool of PPAR-alpha ligands, because addition of exogenous apoCIII inhibited, and removal of endogenous apoCIII potentiated, lipolytic PPAR-alpha activation. These data suggest that the PPAR-alpha response is generated by unbound fatty acids released locally by lipase activity and not by circulating plasma fatty acids.

  18. INCORPORATION OF BACTERIOPHAGE GENOME BY SPORES OF BACILLUS SUBTILIS.

    Science.gov (United States)

    TAKAHASHI, I

    1964-06-01

    Takahashi, I. (Microbiology Research Institute, Ottawa, Ontario, Canada). Incorporation of bacteriophage genome by spores of Bacillus subtilis. J. Bacteriol. 87:1499-1502. 1964-The buoyant density in a CsCl gradient of deoxyribonucleic acid (DNA) extracted from spores of Bacillus subtilis was found to be identical to that of DNA from vegetative cells. Density-gradient centrifugation of DNA of spores derived from cultures infected with phage PBS 1 revealed the presence of a minor band whose density corresponded to that of the phage DNA in addition to the spore DNA. No intermediate bands were present. The relative amount of the phage DNA present in the spores was estimated to be 11%, suggesting that spores of this organism may incorporate several copies of the phage genome. Although the possibility that true lysogeny may occur cannot be entirely eliminated, the results seem to indicate that the phage genomes incorporated into spores are not attached to the host chromosome in this system.

  19. Studies on Alumina Incorporated Polyesteramide Derived from Meliaazedarach Seed Oil

    Directory of Open Access Journals (Sweden)

    A. Hasnat

    2016-10-01

    Full Text Available Polyesteramide resin (MAPEAM was prepared from N,N-bis(2-hydroxy ethyl Meliaazedarach oil fatty amide (HEMAFA a precursor of natural renewable resource using polycondensation reaction with maleic acid. With the view to improve the physico-mechenical properties aluminium was incorporated in backbone of the polymer to obtain the alumina incorporated polyesteramide resin of Meliaazedarach seed oil (Al-MAPEAM. The physico-chemical analyses and spectroscopic techniques were used for the characterization of Al-MAPEAM polymeric resin. The film properties of the Al-MAPEAM were also investigated in different corrosive environments as per standard reported methods. Studies shows that syntheses ofaluminium incorporated polyesteramide using Meliaazedarach seed oil as a starting material provides a more practicable utilization to it.

  20. Substitutions of aspartic acid for glycine-220 and of arginine for glycine-664 in the triple helix of the pro alpha 1(I) chain of type I procollagen produce lethal osteogenesis imperfecta and disrupt the ability of collagen fibrils to incorporate crystalline hydroxyapatite.

    Science.gov (United States)

    Culbert, A A; Lowe, M P; Atkinson, M; Byers, P H; Wallis, G A; Kadler, K E

    1995-01-01

    We identified two infants with lethal (type II) osteogenesis imperfecta (OI) who were heterozygous for mutations in the COL1A1 gene that resulted in substitutions of aspartic acid for glycine at position 220 and arginine for glycine at position 664 in the product of one COL1A1 allele in each individual. In normal age- and site-matched bone, approximately 70% (by number) of the collagen fibrils were encrusted with plate-like crystallites of hydroxyapatite. In contrast, approximately 5% (by number) of the collagen fibrils in the probands' bone contained crystallites. In contrast with normal bone, the c-axes of hydroxyapatite crystallites were sometimes poorly aligned with the long axis of fibrils obtained from OI bone. Chemical analysis showed that the OI samples contained normal amounts of calcium. The probands' bone samples contained type I collagen, overmodified type I collagen and elevated levels of type III and V collagens. On the basis of biochemical and morphological data, the fibrils in the OI samples were co-polymers of normal and mutant collagen. The results are consistent with a model of fibril mineralization in which the presence of abnormal type I collagen prevents normal collagen in the same fibril from incorporating hydroxyapatite crystallites. Images Figure 1 Figure 2 Figure 3 PMID:7487936

  1. Incorporation of mammalian actin into microfilaments in plant cell nucleus

    Directory of Open Access Journals (Sweden)

    Paves Heiti

    2004-04-01

    Full Text Available Abstract Background Actin is an ancient molecule that shows more than 90% amino acid homology between mammalian and plant actins. The regions of the actin molecule that are involved in F-actin assembly are largely conserved, and it is likely that mammalian actin is able to incorporate into microfilaments in plant cells but there is no experimental evidence until now. Results Visualization of microfilaments in onion bulb scale epidermis cells by different techniques revealed that rhodamine-phalloidin stained F-actin besides cytoplasm also in the nuclei whereas GFP-mouse talin hybrid protein did not enter the nuclei. Microinjection of fluorescently labeled actin was applied to study the presence of nuclear microfilaments in plant cells. Ratio imaging of injected fluorescent rabbit skeletal muscle actin and phalloidin staining of the microinjected cells showed that mammalian actin was able to incorporate into plant F-actin. The incorporation occurred preferentially in the nucleus and in the perinuclear region of plant cells whereas part of plant microfilaments, mostly in the periphery of cytoplasm, did not incorporate mammalian actin. Conclusions Microinjected mammalian actin is able to enter plant cell's nucleus, whereas incorporation of mammalian actin into plant F-actin occurs preferentially in the nucleus and perinuclear area.

  2. 49 CFR 587.5 - Incorporated materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials are...

  3. 49 CFR 572.30 - Incorporated materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to change...

  4. 49 CFR 572.80 - Incorporated materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth in full are hereby incorporated in this part by reference. These materials are thereby made part of this...

  5. Numeral Incorporation in Japanese Sign Language

    Science.gov (United States)

    Ktejik, Mish

    2013-01-01

    This article explores the morphological process of numeral incorporation in Japanese Sign Language. Numeral incorporation is defined and the available research on numeral incorporation in signed language is discussed. The numeral signs in Japanese Sign Language are then introduced and followed by an explanation of the numeral morphemes which are…

  6. PELÍCULA ANTIMICROBIANA A BASE DE PROTEÍNA DE SUERO LÁCTEO, INCORPORADA CON BACTERIAS LÁCTICAS COMO CONTROLADOR DE Listeria monocytogenes, APLICADA SOBRE SALMÓN AHUMADO FILM ANTIMICROBIAL BASED WHEY PROTEIN, LACTIC ACID BACTERIA INCORPORATED AS CONTROLLER Listeria monocytogenes APPLIED TO SMOKED SALMON

    Directory of Open Access Journals (Sweden)

    DEYCI RODRÍGUEZ

    2009-12-01

    Full Text Available El concentrado de proteína de suero lácteo (CPS posee propiedades funcionales apropiadas para la elaboración de películas biopreservantes, siendo factible la incorporación de bacterias ácido lácticas (BAL productoras de sustancias tipo bacteriocina (STB y así, lograr un efecto controlador sobre Listeria monocytogenes al ser utilizada como cobertura sobre salmón ahumado. Las condiciones para la formación de la película fueron: CPS 12% p/v, glicerol 18% v/v, pH en solución formadora de película 7,0 y 8,0, y secado a 30°C por 16 horas. La actividad inhibitoria de la película incorporada con las cepas lácticas fue evaluada usando el método de difusión frente a un césped de L. monocytogenes y mediante el recuento en placa, obteniendo: la combinación de dos cepas BAL aumentó la actividad controladora sobre L. monocytogenes logrando reducir hasta 2,1 ciclos logarítmicos el crecimiento de este patógeno, bajo condiciones de refrigeración durante 15 días.The Whey protein concentrated (WPC has functional properties suitable for developing films biopreservantes. Thanks to the functional properties of its components, was feasible the incorporation of lactic acid bacteria (LAB producing substances type bacteriocins (STB and thus achieve and effective control Listeria monocytogenes to be applied on smoked salmon. The conditions for the formation of the film were: CPS 12% w/v, glycerol 18% v/v, pH of film-forming solution 7.0 and 8.0, and dried at 30°C for 16 hours. The study of inhibitory activity of the film incorporated with lactic strains was evaluated using the diffusion method against a lawn of L. monocytogenes and by plate counting, getting the combination BAL-A + B, increases the activity of controlling L. monocytogenes achieving 2.1 log units to reduce the growth of this pathogen under refrigeration for 15 days.

  7. 21 CFR 184.1007 - Aconitic acid.

    Science.gov (United States)

    2010-04-01

    ... salt from cane sugar or molasses. It may be synthesized by sulfuric acid dehydration of citric acid... availability of this incorporation by reference is given in paragraph (b)(1) of this section. (7) Residue...

  8. 温敏型姜黄素鼻用原位凝胶增强脑靶向性%Enhanced Brain Targeting of Curcumin by Intranasal Administration of a Thermosensitive Poloxamer Hydrogel

    Institute of Scientific and Technical Information of China (English)

    陈溪; 杨洪斌; 胡一桥; 杨伊林; 支枫; 汤卫国; 周建平

    2013-01-01

    Objec tive: The aim of this study is to develop a curcumin intranasal thermosensitive hydrogel and to improve its brain targeting efficiency. Methods: The hydrogel gelation temperature and time, the drug release characteristics as well as nose-to-brain transport in a rat model were evaluated. Results: The developed nasal hydrogel composed of Pluronic F127 (PF-127) and Poloxamer 188 (P188) had a shorter gelation time and a longer mucociliary transport time compared with curcumin solution. The hydrogel showed diffusion—controlled drug release when evaluated using the dialysis membrane method. The drug targeting efficiency (DTE) for the drug in the cerebrum, cerebellum, hippocampus and olfactory bulb after intranasal administration of the curcumin hydrogel were respectively 1.82, 2.05, 2.07 and 1.51 times over those after intravenous administration of the curcumin solution injection, indicating that the hydrogel significantly increased the distribution of curcumin into the rat brain tissues. Conclusion: The thermosensitive curcumin nasal gel has been developed with favorable gelation, release properties and enhanced brain uptake efficiency.%目的:制备温度敏感型的姜黄素鼻用凝胶制剂,以提高姜黄素的脑部生物利用度.方法:通过粘度实验进行原位凝胶制剂的处方筛选,以胶凝时间、胶凝温度等为指标,优化处方;采用透析袋法考察原位凝胶的体外释放;以大鼠为模型,考察姜黄素原位凝胶的脑靶向性及脑内分布,并与其静脉注射剂相比较.结果:姜黄素原位凝胶剂优化处方具有最短的胶凝时间,可以长时间粘附在鼻腔粘膜上;释放行为属于Fickian扩散机制;姜黄素脑内分布试验表明,原位凝胶在大脑、小脑、海马、嗅球中的药物靶向效率(DTE)分别为静脉给药的1.82、2.05、2.07、1.51倍,说明原位凝胶给药显著增强了姜黄素的脑靶向性.结论:制备的姜黄素原位凝胶剂具有温度敏感的特点,

  9. Incorporation of tryptophan analogues into the lantibiotic nisin.

    Science.gov (United States)

    Zhou, Liang; Shao, Jinfeng; Li, Qian; van Heel, Auke J; de Vries, Marcel P; Broos, Jaap; Kuipers, Oscar P

    2016-05-01

    Lantibiotics are posttranslationally modified peptides with efficient inhibitory activity against various Gram-positive bacteria. In addition to the original modifications, incorporation of non-canonical amino acids can render new properties and functions to lantibiotics. Nisin is the most studied lantibiotic and contains no tryptophan residues. In this study, a system was constructed to incorporate tryptophan analogues into nisin, which included the modification machinery (NisBTC) and the overexpression of tryptophanyl-tRNA synthetase (TrpRS). Tryptophan and three different tryptophan analogues (5-fluoroTrp (5FW), 5-hydroxyTrp (5HW) and 5-methylTrp (5MeW)) were successfully incorporated at four different positions of nisin (I1W, I4W, M17W and V32W). The incorporation efficiency of tryptophan analogues into mutants I1W, M17W and V32W was over 97 %, while the mutant I4W showed relatively low incorporation efficiency (69-93 %). The variants with 5FW showed relatively higher production yield, while 5MeW-containing variants showed the lowest yield. The dehydration efficiency of serines or threonines was affected by the tryptophan mutants of I4W and V32W. The affinity of the peptides for the cation-ion exchange and reverse phase chromatography columns was significantly reduced when 5HW was incorporated. The antimicrobial activity of IIW and its 5FW analogue both decreased two times compared to that of nisin, while that of its 5HW analogue decreased four times. The 5FW analogue of I4W also showed two times decreased activity than nisin. However, the mutant M17W and its 5HW analogue both showed 32 times reduced activity relative to that of nisin.

  10. Chlorogenic acid stabilized nanostructured lipid carriers (NLC) of atorvastatin: formulation, design and in vivo evaluation.

    Science.gov (United States)

    Khan, Saba; Baboota, Sanjula; Ali, Javed; Narang, R S; Narang, Jasjeet K

    2016-01-01

    The present work was aimed at developing an optimized oral nanostructured lipid carrier (NLC) formulation of poorly soluble atorvastatin Ca (AT Ca) and assessing its in vitro release, oral bioavailability and pharmacodynamic activity. In this study, chlorogenic acid, a novel excipient having synergistic cholesterol lowering activity was utilized and explored in NLC formulation development. The drug-loaded NLC formulations were prepared using a high pressure homogenization technique and optimized by the Box-Behnken statistical design using the Design-Expert software. The optimized NLC formulation was composed of oleic acid and stearic acid as lipid phase (0.9% w/v), poloxamer 188 as surfactant (1% w/v) and chlorogenic acid (0.05% w/v). The mean particle size, polydispersity index (PDI) and % drug entrapment efficiency of optimized NLC were 203.56 ± 8.57 nm, 0.27 ± 0.028 and 83.66 ± 5.69, respectively. In vitro release studies showed that the release of drug from optimized NLC formulations were markedly enhanced as compared to solid lipid nanoparticles (SLN) and drug suspension. The plasma concentration time profile of AT Ca in rats showed 3.08- and 4.89-fold increase in relative bioavailability of developed NLC with respect to marketed preparation (ATORVA® tablet) and drug suspension, respectively. Pharmacodynamic study suggested highly significant (**p oral delivery of AT Ca by means of its chlorogenic acid integrated NLC.

  11. Arabinogalactan proteins are incorporated in negatively charged coffee brew melanoidins.

    Science.gov (United States)

    Bekedam, E Koen; De Laat, Marieke P F C; Schols, Henk A; Van Boekel, Martinus A J S; Smit, Gerrit

    2007-02-07

    The charge properties of melanoidins in high molecular weight (HMw) coffee brew fractions, isolated by diafiltration and membrane dialysis, were studied. Ion exchange chromatography experiments with the HMw fractions showed that coffee brew melanoidins were negatively charged whereas these molecules did not expose any positive charge at the pH of coffee brew. Fractions with different ionic charges were isolated and subsequently characterized by means of the specific extinction coefficient (K(mix 405nm)), sugar composition, phenolic group content, nitrogen content, and the arabinogalactan protein (AGP) specific Yariv gel-diffusion assay. The isolated fractions were different in composition and AGP was found to be present in one of the HMw fractions. The AGP accounted for 6% of the coffee brew dry matter and had a moderate negative charge, probably caused by the presence of uronic acids. As the fraction that precipitated with Yariv was brown (K(mix 405nm) = 1.2), compared to a white color in the green bean, it was concluded that these AGPs had undergone Maillard reaction resulting in an AGP-melanoidin complex. The presence of mannose (presumably from galactomannan) indicates the incorporation of galactomannans in the AGP-melanoidin complex. As the uronic acid content in the more negatively charged melanoidin-rich, AGP-poor HMw fractions decreased, it was hypothesized that acidic groups are formed or incorporated during melanoidin formation.

  12. 49 CFR 572.40 - Incorporated materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the Federal...

  13. Incorporating Sociology into Community Service Classes

    Science.gov (United States)

    Hochschild, Thomas R., Jr.; Farley, Matthew; Chee, Vanessa

    2014-01-01

    Sociologists and instructors who teach about community service share an affinity for understanding and addressing social problems. While many studies have demonstrated the benefits of incorporating community service into sociology courses, we examine the benefits of incorporating sociological content into community service classes. The authors…

  14. Enzymatic tRNA acylation by acid and alpha-hydroxy acid analogues of amino acids.

    Science.gov (United States)

    Owczarek, Alina; Safro, Mark; Wolfson, Alexey D

    2008-01-08

    Incorporation of unnatural amino acids with unique chemical functionalities has proven to be a valuable tool for expansion of the functional repertoire and properties of proteins as well as for structure-function analysis. Incorporation of alpha-hydroxy acids (primary amino group is substituted with hydroxyl) leads to the synthesis of proteins with peptide bonds being substituted by ester bonds. Practical application of this modification is limited by the necessity to prepare corresponding acylated tRNA by chemical synthesis. We investigated the possibility of enzymatic incorporation of alpha-hydroxy acid and acid analogues (lacking amino group) of amino acids into tRNA using aminoacyl-tRNA synthetases (aaRSs). We studied direct acylation of tRNAs by alpha-hydroxy acid and acid analogues of amino acids and corresponding chemically synthesized analogues of aminoacyl-adenylates. Using adenylate analogues we were able to enzymatically acylate tRNA with amino acid analogues which were otherwise completely inactive in direct aminoacylation reaction, thus bypassing the natural mechanisms ensuring the selectivity of tRNA aminoacylation. Our results are the first demonstration that the use of synthetic aminoacyl-adenylates as substrates in tRNA aminoacylation reaction may provide a way for incorporation of unnatural amino acids into tRNA, and consequently into proteins.

  15. Efficacy of the biomaterials 3wt%-nanostrontium-hydroxyapatite-enhanced calcium phosphate cement (nanoSr-CPC) and nanoSr-CPC-incorporated simvastatin-loaded poly(lactic-co-glycolic-acid) microspheres in osteogenesis improvement: An explorative multi-phase experimental in vitro/vivo study.

    Science.gov (United States)

    Masaeli, Reza; Jafarzadeh Kashi, Tahereh Sadat; Dinarvand, Rassoul; Rakhshan, Vahid; Shahoon, Hossein; Hooshmand, Behzad; Mashhadi Abbas, Fatemeh; Raz, Majid; Rajabnejad, Alireza; Eslami, Hossein; Khoshroo, Kimia; Tahriri, Mohammadreza; Tayebi, Lobat

    2016-12-01

    The purpose of this multi-phase explorative in vivo animal/surgical and in vitro multi-test experimental study was to (1) create a 3wt%-nanostrontium hydroxyapatite-enhanced calcium phosphate cement (Sr-HA/CPC) for increasing bone formation and (2) creating a simvastatin-loaded poly(lactic-co-glycolic acid) (SIM-loaded PLGA) microspheres plus CPC composite (SIM-loaded PLGA+nanostrontium-CPC). The third goal was the extensive assessment of multiple in vitro and in vivo characteristics of the above experimental explorative products in vitro and in vivo (animal and surgical studies). Physical and chemical properties of the prepared Sr-HA/CPC were evaluated. MTT assay and alkaline phosphatase activities, and radiological and histological examinations of Sr-HA/CPC, CPC and negative control were compared. X-ray diffraction (XRD) indicated that crystallinity of the prepared cement increased by increasing the powder-to-liquid ratio. Incorporation of Sr-HA into CPC increased MTT assay (biocompatibility) and ALP activity (P<0.05). Histomorphometry showed greater bone formation after 4weeks, after implantation of Sr-HA/CPC in 10 rats compared to implantations of CPC or empty defects in the same rats (n=30, ANOVA P<0.05). METHODS AND RESULTS PERTAINING TO SIM-LOADED PLGA MICROSPHERES+NANOSTRONTIUM-CPC COMPOSITE: After SEM assessment, the produced composite of microspheres and enhanced CPC were implanted for 8weeks in 10 rabbits, along with positive and negative controls, enhanced CPC, and enhanced CPC plus SIM (n=50). In the control group, only a small amount of bone had been regenerated (localized at the boundary of the defect); whereas, other groups showed new bone formation within and around the materials. A significant difference was found in the osteogenesis induced by the groups sham control (16.96±1.01), bone materials (32.28±4.03), nanostrontium-CPC (24.84±2.6), nanostrontium-CPC-simvastatin (40.12±3.29), and SIM-loaded PLGA+nanostrontium-CPC (44.8±6.45) (ANOVA P

  16. Kinetics of Incorporation of Structural Proteins into Sindbis Virions

    Science.gov (United States)

    Scheele, Christina M.; Pfefferkorn, E. R.

    1969-01-01

    The morphogenesis of Sindbis virus was studied by determining the kinetics with which newly synthesized nucleocapsid and envelope proteins appeared in virions released into the extracellular medium. Assembly of the nucleocapsid was more rapid than modification of the cellular membrane by the addition of the viral envelope protein. However, both viral structural proteins were efficiently incorporated into virions; a 0.5-hr pulse-labeling period resulted in the release of maximally labeled virus during the next hour. When protein synthesis was inhibited, release of virus soon declined even though large amounts of both viral structural proteins were present within the cell and ribonucleic acid replication was unaffected. PMID:5771964

  17. Inhibitory effect of some triterpenes from cacti on 32Pi-incorporation into phospholipids of HeLa cells promoted by 12-O-tetradecanoylphorbol-13-acetate.

    Science.gov (United States)

    Kinoshita, K; Yang, Y; Koyama, K; Takahashi, K; Nishino, H

    1999-05-01

    Seventeen triterpenes isolated from cacti and the 10 derivatives were examined for the inhibition of tumor promoter-induced effects in vitro, such as stimulation of 32Pi-incorporation into phospholipids of cultured cells. Betulinic acid (1), cochalic acid (15), erythrodiol (16), oleanolic acid (21) and queretaroic acid (24) inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulated 32Pi-incorporation into phospholipids of the cultured cells.

  18. Disaster risk communication: A dichotomous approach incorporating ...

    African Journals Online (AJOL)

    Disaster risk communication: A dichotomous approach incorporating ... knowledge systems and modern risk communication management is found in ... The proposed model will undoubtedly provoke academic debate and help inform policy in ...

  19. Cotton Incorporated Documents Industry Gains at ICAC

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Those who attack the cotton industry for its perceived impact on the environment will need to have their facts straight, thanks to a major research project undertaken by Cotton Incorporated: a life-cycle assessment (LCA) for cotton.

  20. Composites incorporated a conductive polymer nanofiber network

    Energy Technology Data Exchange (ETDEWEB)

    Pozzo, Lilo Danielle; Newbloom, Gregory

    2017-04-11

    Methods of forming composites that incorporate networks of conductive polymer nanofibers are provided. Networks of less-than conductive polymers are first formed and then doped with a chemical dopant to provide networks of conductive polymers. The networks of conductive polymers are then incorporated into a matrix in order to improve the conductivity of the matrix. The formed composites are useful as conductive coatings for applications including electromagnetic energy management on exterior surfaces of vehicles.

  1. Incorporation of peptides in phospholipid aggregates using ultrasound.

    Science.gov (United States)

    Silva, Raquel; Little, Collin; Ferreira, Helena; Cavaco-Paulo, Artur

    2008-09-01

    This study presents the highlights of ultrasonic effects on peptides incorporated on phospholipid aggregates (liposomes). These liposomes or vesicles are known as transport agents in skin drug delivery and for hair treatment. They might be a good model to deliver larger peptides into hair to restore fibre strength after hair coloration, modelling, permanent wave and/or straightening. The preparation of liposomes 1,2-dipalmitoyl-sn-glycerol-3-phosphocholine (DPPC) with peptides (LLLLK LLLLK LLLLK LLLLK; LLLLL LCLCL LLKAK AK) was made by the thin film hydration method. The LUVs (uni-lamellar vesicles) were obtained by sonication, applying different experimental conditions, such as depth (mm) and power intensity (%). Photon-correlation spectroscopy (PCS) and electronic microscopy (EM) results confirmed that the incorporation of these peptides, with different sequence of amino acids, presented differences on the diameter, zeta-potential of membrane surface and shape of liposomes. The liposomes that included peptide LLLLK LLLLK LLLLK LLLLK present an increased in zeta-potential values after using ultrasound and an "amorphous" aspect. Conversely, the liposomes that incorporated the peptide LLLLL LCLCL LLKAK AK presented a define shape (rod shape) and the potential surface of liposome did not change significantly by the use of ultrasound.

  2. Improving the Hydrophobicity of ZnO by PTFE Incorporation

    Directory of Open Access Journals (Sweden)

    Meenu Srivastava

    2011-01-01

    Full Text Available The objective of the present study is to obtain a zinc oxide- (ZnO- based superhydrophobic surface in a simple and cost-effective manner. Chemical immersion deposition being simple and economical has been adopted to develop modified ZnO coating on glass substrate. Several modifications of ZnO like treatment with alkanoic acid (stearic acid and fluoroalkylsilane to tune the surface wettability (hydrophobicity were attempted. The effect of thermal treatment on the hydrophobic performance was also studied. It was observed that thermal treatment at 70°C for 16 hrs followed by immersion in stearic acid resulted in high water contact angle (WCA, that is, a superhydrophobic surface. Thus, a modified ZnO superhydrophobic surface involves the consumption of large amount of electrical energy and time. Hence, the alternate involved the incorporation of low surface energy fluoropolymer polytetrafluoroethylene (PTFE in the ZnO coating. The immersion deposited ZnO-PTFE composite coating on modification with either stearic acid or fluoroalkylsilane resulted in a better superhydrophobic surface. The coatings were characterized using Scanning Electron Microscope (SEM for the surface morphology. It was found that microstructure of the coating was influenced by the additives employed. A flower-like morphology comprising of needle-like structure arranged in a radial manner was exhibited by the superhydrophobic coating.

  3. Modulation of nanotube formation in apatite single crystal via organic molecule incorporation

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Takuya, E-mail: tmatsu@dent.osaka-u.ac.jp [Department of Oromaxillofacial Regeneration, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Uddin, Mohammad Hafiz; An, Sang Hyun [Department of Oromaxillofacial Regeneration, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Arakawa, Kazuto; Taguchi, Eiji [Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki 567-0047 (Japan); Nakahira, Atsushi [Department of Material Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai 599-8531 (Japan); Okazaki, Masayuki [Department of Biomaterials Science, Hiroshima University Faculty of Dentistry, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan)

    2011-08-15

    Highlights: {yields} Hydroxyapatite incorporating amino acid was fabricated. {yields} The synthesized crystals showed linearly aligned nano-pores in their structure after their EB irradiation or heating. {yields} Amino acid is considered as an effective porogen for the modulation of internal structure of apatite single crystal. - Abstract: Hydroxyapatite materials are potentially useful for biomedical application, especially as vehicles for functional molecules. Structural control of bulk apatite materials, such as in the fabrication of hollow microspheres or porous structures, has been studied for this purpose. However, control of the internal structure of the source apatite crystal itself is still a challenge. Here, we show that small organic molecules incorporated in apatite crystals act as porogens which control the porous structure of apatite single crystal. The presence of amino acid under apatite synthesis conditions leads to firm bindings and encapsulation of the amino acid in apatite single crystals. Amino acid elimination by heating or electron beam irradiation enhances the pore formation in apatite single crystal. Moreover, incorporation of an acidic amino acid in apatite induces peapod like nanotubes in apatite single crystals. This study suggests the potential of using small organics for nano-structural control of apatite single crystals which would be valuable for enhancing drug loadings or modulating material digestion in vivo.

  4. Nanostructured lipid carriers for incorporation of copper(II) complexes to be used against Mycobacterium tuberculosis

    Science.gov (United States)

    Sato, Mariana R; Oshiro Junior, João A; Machado, Rachel TA; de Souza, Paula C; Campos, Débora L; Pavan, Fernando R; da Silva, Patricia B; Chorilli, Marlus

    2017-01-01

    Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis. Cessation of treatment before the recommended conclusion may lead to the emergence of multidrug-resistant strains. The aim of this study was to develop nanostructured lipid carriers (NLCs) for use in the treatment of M. tuberculosis. The NLCs comprised the following lipid phase: 2.07% polyoxyethylene 40 stearate, 2.05% caprylic/capric triglyceride, and 0.88% polyoxyl 40 hydrogenated castor oil; the following aqueous phase: 3.50% poloxamer 407 (F1–F6), and 0.50% cetyltrimethylammonium bromide (F7–F12); and incorporated the copper(II) complexes [CuCl2(INH)2]·H2O (1), [Cu(NCS)2(INH)2]·5H2O (2), and [Cu(NCO)2(INH)2]·4H2O (3) to form compounds F11.1, F11.2, and F11.3, respectively. The mean diameter of F11, F11.1, F11.2, and F11.3 ranged from 111.27±21.86 to 134.25±22.72 nm, 90.27±12.97 to 116.46±9.17 nm, 112.4±10.22 to 149.3±15.82 nm, and 78.65±6.00 to 122.00±8.70 nm, respectively. The polydispersity index values for the NLCs ranged from 0.13±0.01 to 0.30±0.09. The NLCs showed significant changes in zeta potential, except for F11.2, with F11, F11.1, F11.2, and F11.3 ranging from 18.87±4.04 to 23.25±1.13 mV, 17.03±1.77 to 21.42±1.87 mV, 20.51±1.88 to 22.60±3.44 mV, and 17.80±1.96 to 25.25±7.78 mV, respectively. Atomic force microscopy confirmed the formation of nanoscale spherical particle dispersions by the NLCs. Differential scanning calorimetry determined the melting points of the constituents of the NLCs. The in vitro activity of copper(II) complex-loaded NLCs against M. tuberculosis H37Rv showed an improvement in the anti-TB activity of 55.4, 27.1, and 41.1 times the activity for complexes 1, 2, and 3, respectively. An in vivo acute toxicity study of complex-loaded NLCs demonstrated their reduced toxicity. The results suggest that NLCs may be a powerful tool to optimize the activity of copper(II) complexes against M. tuberculosis. PMID:28356717

  5. Nanostructured lipid carriers for incorporation of copper(II complexes to be used against Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Sato MR

    2017-03-01

    Full Text Available Mariana R Sato,1 João A Oshiro Junior,1 Rachel TA Machado,1 Paula C de Souza,2 Débora L Campos,2 Fernando R Pavan,2 Patricia B da Silva,1,* Marlus Chorilli1,* 1Department of Drugs and Medicines, Faculdade de Ciências Farmacêuticas, UNESP – Univ Estadual Paulista, Campus Araraquara, Araraquara, SP, Brazil; 2Department of Biological Sciences, Faculdade de Ciências Farmacêuticas, UNESP – Univ Estadual Paulista, Campus Araraquara, Araraquara, SP, Brazil *These authors contributed equally to this work Abstract: Tuberculosis (TB is a disease caused by Mycobacterium tuberculosis. Cessation of treatment before the recommended conclusion may lead to the emergence of multidrug-resistant strains. The aim of this study was to develop nanostructured lipid carriers (NLCs for use in the treatment of M. tuberculosis. The NLCs comprised the following lipid phase: 2.07% polyoxyethylene 40 stearate, 2.05% caprylic/capric triglyceride, and 0.88% polyoxyl 40 hydrogenated castor oil; the following aqueous phase: 3.50% poloxamer 407 (F1–F6, and 0.50% cetyltrimethylammonium bromide (F7–F12; and incorporated the copper(II complexes [CuCl2(INH2]·H2O (1, [Cu(NCS2(INH2]·5H2O (2, and [Cu(NCO2(INH2]·4H2O (3 to form compounds F11.1, F11.2, and F11.3, respectively. The mean diameter of F11, F11.1, F11.2, and F11.3 ranged from 111.27±21.86 to 134.25±22.72 nm, 90.27±12.97 to 116.46±9.17 nm, 112.4±10.22 to 149.3±15.82 nm, and 78.65±6.00 to 122.00±8.70 nm, respectively. The polydispersity index values for the NLCs ranged from 0.13±0.01 to 0.30±0.09. The NLCs showed significant changes in zeta potential, except for F11.2, with F11, F11.1, F11.2, and F11.3 ranging from 18.87±4.04 to 23.25±1.13 mV, 17.03±1.77 to 21.42±1.87 mV, 20.51±1.88 to 22.60±3.44 mV, and 17.80±1.96 to 25.25±7.78 mV, respectively. Atomic force microscopy confirmed the formation of nanoscale spherical particle dispersions by the NLCs. Differential scanning calorimetry determined

  6. Incorporating Duration Information in Activity Recognition

    Science.gov (United States)

    Chaurasia, Priyanka; Scotney, Bryan; McClean, Sally; Zhang, Shuai; Nugent, Chris

    Activity recognition has become a key issue in smart home environments. The problem involves learning high level activities from low level sensor data. Activity recognition can depend on several variables; one such variable is duration of engagement with sensorised items or duration of intervals between sensor activations that can provide useful information about personal behaviour. In this paper a probabilistic learning algorithm is proposed that incorporates episode, time and duration information to determine inhabitant identity and the activity being undertaken from low level sensor data. Our results verify that incorporating duration information consistently improves the accuracy.

  7. Fatty Acid Biosynthesis IX

    DEFF Research Database (Denmark)

    Carey, E. M.; Hansen, Heinz Johs. Max; Dils, R.

    1972-01-01

    # 1. I. [I-14C]Acetate was covalently bound to rabbit mammary gland fatty acid synthetase by enzymic transacylation from [I-14C]acetyl-CoA. Per mole of enzyme 2 moles of acetate were bound to thiol groups and up to I mole of acetate was bound to non-thiol groups. # 2. 2. The acetyl-fatty acid...... synthetase complex was isolated free from acetyl-CoA. It was rapidly hydrolysed at 30°C, but hydrolysis was greatly diminished at o°C and triacetic lactone synthesis occurred. In the presence of malonyl-CoA and NADPH, all the acetate bound to fatty acid synthetase was incorporated into long-chain fatty acids....... Hydrolysis of bound acetate and incorporation of bound acetate into fatty acids were inhibited to the same extent by guanidine hydrochloride. # 3. 3. Acetate was also covalently bound to fatty acid synthetase by chemical acetylation with [I-14C]acetic anhydride in the absence of CoASH. A total of 60 moles...

  8. Contact, Incorporation, and the North American Southeast

    Directory of Open Access Journals (Sweden)

    Shirley A. Hollis

    2015-08-01

    Full Text Available The broadening of the world-system, which involves the geographic expansion into previously external areas and integration of new economies into its network of economic relationships, is represented in world-system scholarship by two competing views. On the one hand, Wallerstein and his associates treat incorporation as being specifically contingent on the routine and systematic economic exchange for durable goods produced in the previously external area to the benefit of the core. In contrast, Hall and Chase-Dunn contend that incorporation is a synchronous process that takes different forms depending onthe relative locations within the hierarchical world-economy of both the previously external areas and the “incorporating” area. Using the sixteenth-century North American Southeast as an episode of incorporation, this study examines the contact relationship between early European explorers and the indigenous groups in the formerly external area. My goal is to illuminate more fully how contact may permanently alter the social organization and relations within the region and, consequently, the form taken by subsequent integration into the world-system.

  9. Incorporating the Aesthetic Dimension into Pedagogy

    Science.gov (United States)

    Webster, R. Scott; Wolfe, Melissa

    2013-01-01

    This paper reports on a case study that was undertaken to discover not only the belief and intent behind the everyday opportunities that four exemplary teachers offered their high performing students but what activities they incorporated into their everyday lessons in an attempt to make sense of how aesthetic experiences may enhance learning. The…

  10. Incorporating Feminism into Rehabilitation Counselor Education

    Science.gov (United States)

    Jeon, Mookyong

    2015-01-01

    Purpose: The author describes how rehabilitation counselor educators can incorporate the feminist perspective in teaching rehabilitation counselors-in-training by exploring history, core values, and training methods of feminism. Method: Based on a literature review, the author compares philosophy and concepts of rehabilitation counseling and…

  11. Incorporating Feminism into Rehabilitation Counselor Education

    Science.gov (United States)

    Jeon, Mookyong

    2015-01-01

    Purpose: The author describes how rehabilitation counselor educators can incorporate the feminist perspective in teaching rehabilitation counselors-in-training by exploring history, core values, and training methods of feminism. Method: Based on a literature review, the author compares philosophy and concepts of rehabilitation counseling and…

  12. Incorporating groundwater flow into the WEPP model

    Science.gov (United States)

    William Elliot; Erin Brooks; Tim Link; Sue Miller

    2010-01-01

    The water erosion prediction project (WEPP) model is a physically-based hydrology and erosion model. In recent years, the hydrology prediction within the model has been improved for forest watershed modeling by incorporating shallow lateral flow into watershed runoff prediction. This has greatly improved WEPP's hydrologic performance on small watersheds with...

  13. 49 CFR 572.180 - Incorporated materials.

    Science.gov (United States)

    2010-10-01

    ...,” incorporated by reference in §§ 572.180(a)(2), and 572.181(a); (4) Society of Automotive Engineers (SAE... paragraphs (a)(4) and (a)(5) of this section are available from the Society of Automotive Engineers,...

  14. Incorporating Social Media in the Classroom

    Science.gov (United States)

    McMeans, April

    2015-01-01

    Incorporating social media into the classroom will provide a positive, upbeat learning environment that students are engaged in on a regular basis. In doing this, educators will be ensuring discussion, collaboration, critical thinking, and creativity amongst their students. Social media is a knowledgeable topic for our students, and it is an…

  15. Incorporating the dimensions of sustainability into information ...

    African Journals Online (AJOL)

    Incorporating the dimensions of sustainability into information systems ... Although research has been done on sustainability in project management, ... This article reports on whether IS projects are executed sustainably and ... A questionnaire, completed by 650 IS project managers, was used to determine the state of IS ...

  16. Incorporated Organic Modified Ag Nanoparticles in Ormocer

    Institute of Scientific and Technical Information of China (English)

    Haiping XIA; Jianli ZHANG; Jinhao WANG; Qiuhua NIE

    2004-01-01

    Ag nanoparticles coated trisodium citrate were incorporated in ormocer by sol-gel method. The doping concentration of Ag in ormocer is about 1.0% in weight. The HRTFM demonstrated that the particles disperse in ormocer, and the size of Ag nanoparticles is 5~10 nm. The absorption band of Ag nanoparticle at 410 nm was observed.

  17. Incorporating PACER into an Inclusive Basketball Unit

    Science.gov (United States)

    Cervantes, Carlos M.; Cohen, Rona; Hersman, Bethany L.; Barrett, Tim

    2007-01-01

    Cooperative learning is an instructional method designed to teach students to work together in small, structured, heterogeneous teams to achieve a common goal. The Performer and Coach Earn Rewards (PACER) system is a new way to incorporate cooperative learning in the gymnasium. It consists of six components that help teachers to introduce new…

  18. Semiconducting compounds and devices incorporating same

    Energy Technology Data Exchange (ETDEWEB)

    Marks, Tobin J; Facchetti, Antonio; Boudreault, Pierre-Luc; Miyauchi, Hiroyuki

    2014-06-17

    Disclosed are molecular and polymeric compounds having desirable properties as semiconducting materials. Such compounds can exhibit desirable electronic properties and possess processing advantages including solution-processability and/or good stability. Organic transistor and photovoltaic devices incorporating the present compounds as the active layer exhibit good device performance.

  19. Semiconducting compounds and devices incorporating same

    Energy Technology Data Exchange (ETDEWEB)

    Marks, Tobin J.; Facchetti, Antonio; Boudreault, Pierre-Luc; Miyauchi, Hiroyuki

    2016-01-19

    Disclosed are molecular and polymeric compounds having desirable properties as semiconducting materials. Such compounds can exhibit desirable electronic properties and possess processing advantages including solution-processability and/or good stability. Organic transistor and photovoltaic devices incorporating the present compounds as the active layer exhibit good device performance.

  20. Acidic deposition ("acid rain")

    Science.gov (United States)

    Schreiber, R. Kent; LaRoe, Edward T.; Farris, Gaye S.; Puckett, Catherine E.; Doran, Peter D.; Mac, Michael J.

    1995-01-01

    Acidic deposition, or "acid rain," describes any form of precipitation, including rain, snow, and fog, with a pH of 5.5 or below (Note: pH values below 7 are acidic; vinegar has a pH of 3). It often results when the acidity of normal precipitation is increased by sulfates and nitrates that are emitted into the atmosphere from burning fossil fuels. This form of airborne contamination is considered harmful, both directly and indirectly, to a host of plant and animal species.Although acid rain can fall virtually anywhere, ecological damages in environmentally sensitive areas downwind of industrial and urban emissions are a major concern. This includes areas that have a reduced capacity to neutralize acid inputs because of low alkalinity soils and areas that contain species with a low tolerance to acid conditions. To determine the distribution of acidic deposition and evaluate its biological effects, research and monitoring are being conducted by the federal government with support from states, universities, and private industry.            The national extent of the acid rain problem has been estimated by sampling water from 3,000 lakes and 500 streams (Irving 1991), representing more than 28,000 lakes and 56,000 stream reaches with a total of 200,000 km (125,000 mi). Some particularly sensitive areas, such as the Adirondack Mountain region, have been more intensively sampled and the biota examined in detail for effects from acidity.         To identify trends in aquatic ecosystems, present and historical survey data on water chemistry and associated biota are compared. In lakes, the chemical and biological history and pH trends may be inferred or reconstructed in some cases by examining assemblages of fossil diatoms and aquatic invertebrates in the sediment layers. In terrestrial ecosystems, vegetation damage is surveyed and effects of acidic deposition to plants and animals are determined from laboratory and field exposure experiments. Natural

  1. Toxicity and immunogenicity of Neisseria meningitidis lipopolysaccharide incorporated into liposomes.

    Science.gov (United States)

    Petrov, A B; Semenov, B F; Vartanyan, Y P; Zakirov, M M; Torchilin, V P; Trubetskoy, V S; Koshkina, N V; L'Vov, V L; Verner, I K; Lopyrev, I V

    1992-09-01

    To obtain nontoxic and highly immunogenic lipopolysaccharide (LPS) for immunization, we incorporated Neisseria meningitidis LPS into liposomes. Native LPS and its salts were incorporated by the method of dehydration-rehydration of vesicles or prolonged cosonication. The most complete incorporation of LPS into liposomes and a decrease in toxicity were achieved by the method of dehydration-rehydration of vesicles. Three forms of LPS (H+ form, Mg2+ salt, and triethanolamine salt) showed different solubilities in water, the acidic form of LPS, with the most pronounced hydrophobic properties, being capable of practically complete association with liposomal membranes. An evaluation of the activity of liposomal LPS in vitro (by the Limulus amoebocyte test) and in vivo (by monitoring the pyrogenic reaction in rabbits) revealed a decrease in endotoxin activity of up to 1,000-fold. In addition, the pyrogenic activity of liposomal LPS was comparable to that of a meningococcal polysaccharide vaccine. Liposomes had a pronounced adjuvant effect on the immune response to LPS. Thus, the level of anti-LPS plaque-forming cells in the spleens of mice immunized with liposomal LPS was 1 order of magnitude higher and could be observed for a longer time (until day 21, i.e., the term of observation) than in mice immunized with free LPS. The same regularity was revealed in a study done with an enzyme-linked immunosorbent assay. This study also established that antibodies induced by immunization belonged to the immunoglobulin M and G classes, which are capable of prolonged circulation. Moreover, liposomal LPS induced a pronounced immune response in CBA/N mice (defective in B lymphocytes of the LyB-5+ subpopulation). The latter results indicate that the immunogenic action of liposomal LPS occurs at an early age.

  2. Assessment of stable isotope incorporation into recombinant proteins.

    Science.gov (United States)

    Zhang, Xin; Luo, Quanzhou; Apostol, Izydor; Luo, Shun; Jerums, Matthew; Huang, Gang; Jiang, Xinzhao Grace; Gastwirt, Jessica; Savjani, Nimesh; Lewis, Jeffrey; Keener, Ronald; Wypych, Jette

    2013-02-15

    Stable isotope labeling combined with mass spectrometry has been widely used in a diverse set of applications in the biochemistry and biomedical fields. When stable isotope-labeled proteins are produced via metabolic labeling of cell culture, a comprehensive assessment of the labeling pattern is imperative. In this study, we present a set of mass spectrometry-based bioanalytical tools developed for quantitatively tracing the levels of the stable isotopes incorporated into the recombinant proteins (monoclonal antibodies and Fc fusion proteins expressed in different host systems) that include total mass analysis, peptide mapping analysis, and amino acid analysis. We show that these three mass spectrometry-based analytical methods have distinctive advantages and limitations and that they are mutually complementary in evaluating the quality of stable isotope-labeled proteins. In addition, we show that the analytical techniques developed here are powerful tools to provide valuable insights into studying cell metabolism and performing flux analysis during cell culture.

  3. Uptake and incorporation of pyrimidines in Euglena gracilis.

    Science.gov (United States)

    Wasternack, C H

    1976-08-01

    In photoorganotrophically grown cells of Euglena gracilis the uptake and incorporation degree of 12 different pyrimidines were tested. The rate of uptake of pyrimidines has distinct maxima in the late log phase and in the stationary phase of cell multiplication. The kinetics of uptake are linear in the first 2 h, do not show saturation at various concentrations and increase with the concetrations. No accumulation of the pyrimidines at various concentrations could be observed in the first 2 h of incubation. Membrane inhibitors as uranyl acetate inhibit the uptake of the reference substance alpha-AIB, which is wellknown transported by an active transport mechanism, but have no effect on uptake rate of uracil and cytosine. It could not be observed an energy requirement tested in temperature dependence and with electron transport inhibitors. Uptake of uridine, uracil, barbituric acid and alpha-AIB is inhibited by cycloheximide in a different manner after 5 - 10 min.

  4. Fabrication of anodic aluminum oxide with incorporated chromate ions

    Science.gov (United States)

    Stępniowski, Wojciech J.; Norek, Małgorzata; Michalska-Domańska, Marta; Bombalska, Aneta; Nowak-Stępniowska, Agata; Kwaśny, Mirosław; Bojar, Zbigniew

    2012-10-01

    The anodization of aluminum in 0.3 M chromic acid is studied. The influence of operating conditions (like anodizing voltage and electrolyte's temperature) on the nanoporous anodic aluminum oxide geometry (including pore diameter, interpore distance, the oxide layer thickness and pores density) is thoroughly investigated. The results revealed typical correlations of the anodic alumina nanopore geometry with operating conditions, such as linear increase of pore diameter and interpore distance with anodizing voltage. The anodic aluminum oxide is characterized by a low pores arrangement, as determined by Fast Fourier transforms analyses of the FE-SEM images, which translates into a high concentration of oxygen vacancies. Moreover, an optimal experimental condition where chromate ions are being successfully incorporated into the anodic alumina walls, have been determined: the higher oxide growth rate the more chromate ions are being trapped. The trapped chromate ions and a high concentration of oxygen vacancies make the anodic aluminum oxide a promising luminescent material.

  5. Rapid mass spectrometric analysis of 15N-Leu incorporation fidelity during preparation of specifically labeled NMR samples

    DEFF Research Database (Denmark)

    Truhlar, Stephanie M E; Cervantes, Carla F; Torpey, Justin W

    2008-01-01

    Advances in NMR spectroscopy have enabled the study of larger proteins that typically have significant overlap in their spectra. Specific (15)N-amino acid incorporation is a powerful tool for reducing spectral overlap and attaining reliable sequential assignments. However, scrambling of the label...... during protein expression is a common problem. We describe a rapid method to evaluate the fidelity of specific (15)N-amino acid incorporation. The selectively labeled protein is proteolyzed, and the resulting peptides are analyzed using MALDI mass spectrometry. The (15)N incorporation is determined...... by analyzing the isotopic abundance of the peptides in the mass spectra using the program DEX. This analysis determined that expression with a 10-fold excess of unlabeled amino acids relative to the (15)N-amino acid prevents the scrambling of the (15)N label that is observed when equimolar amounts are used...

  6. Lipophorin Drives Lipid Incorporation and Metabolism in Insect Trypanosomatids.

    Science.gov (United States)

    Ximenes, Aline dos Anjos; Silva-Cardoso, Lívia; De Cicco, Nuccia Nicole T; Pereira, Miria G; Lourenço, Daniela C; Fampa, Patricia; Folly, Evelize; Cunha-e-Silva, Narcisa L; Silva-Neto, Mario A C; Atella, Georgia C

    2015-07-01

    Insect trypanosomatids are inhabitants of the insect digestive tract. These parasites can be either monoxenous or dixenous. Plant trypanosomatids are known as insect trypanosomatids once they and are transmitted by phytophagous insects. Such parasites can be found in latex, phloem, fruits and seeds of many plant families. Infections caused by these pathogens are a major cause of serious economic losses. Studies by independent groups have demonstrated the metabolic flow of lipids from the vertebrate host to trypanosomatids. This mechanism is usually present when parasites possess an incomplete de novo lipid biosynthesis pathway. Here, we show that both insect trypanosomatids Phytomonas françai and Leptomonas wallacei incorporate (3)H-palmitic acid and inorganic phosphate. These molecules are used for lipid biosynthesis. Moreover, we have isolated the main hemolymphatic lipoprotein, Lipophorin (Lp) from Oncopeltus fasciatus, the natural insect vector of such parasites. Both parasites were able to incorporate Lp to be utilized both as a lipid and protein source for their metabolism. Also, we have observed the presence of Lp binding sites in the membrane of a parasite. In conclusion, we believe that the elucidation of trypanosomatid metabolic pathways will lead to a better understanding of parasite-host interactions and the identification of novel potential chemotherapy targets.

  7. Emissive sensors and devices incorporating these sensors

    Science.gov (United States)

    Swager, Timothy M; Zhang, Shi-Wei

    2013-02-05

    The present invention generally relates to luminescent and/or optically absorbing compositions and/or precursors to those compositions, including solid films incorporating these compositions/precursors, exhibiting increased luminescent lifetimes, quantum yields, enhanced stabilities and/or amplified emissions. The present invention also relates to sensors and methods for sensing analytes through luminescent and/or optically absorbing properties of these compositions and/or precursors. Examples of analytes detectable by the invention include electrophiles, alkylating agents, thionyl halides, and phosphate ester groups including phosphoryl halides, cyanides and thioates such as those found in certain chemical warfare agents. The present invention additionally relates to devices and methods for amplifying emissions, such as those produced using the above-described compositions and/or precursors, by incorporating the composition and/or precursor within a polymer having an energy migration pathway. In some cases, the compositions and/or precursors thereof include a compound capable of undergoing a cyclization reaction.

  8. Voltage Stability Evaluation Incorporating Wind Power Intermittency

    Institute of Scientific and Technical Information of China (English)

    Libao SHI; Yang ZHAO; Yixin NI; Liangzhong YAO; Masoud BAZARGAN

    2013-01-01

    A simulation framework is proposed to evaluate the voltage stability of power systems incorporating wind power intermittency.Firstly,the power output modelings of three types of wind turbines are discussed.Secondly,the Jensen model is employed to simulate the wind farm with the wake effect.The Monte Carlo based technique is used to conduct the voltage stability evaluation incorporating the randomness of the wind speed based on the Weibull probability distribution.Thirdly,the relative sensitivity index (RSI) is calculated to identify weak buses during analysis.Finally,case studies with different simulation scenarios are carried out.Some statistical results involving weakness probability,expected value and variance of RSI as well as preliminary conclusions are drawn based on numerical simulation results.

  9. Low Voltage Power Supply Incorporating Ceramic Transformer

    CERN Document Server

    Imori, M

    2007-01-01

    A low voltage power supply provides the regulated output voltage of 1 V from the supply voltage around 48 V. The low voltage power supply incorporates a ceramic transformer which utilizes piezoelectric effect to convert voltage. The ceramic transformer isolates the secondary from the primary, thus providing the ground isolation between the supply and the output voltages. The ceramic transformer takes the place of the conventional magnetic transformer. The ceramic transformer is constructed from a ceramic bar and does not include any magnetic material. So the low voltage power supply can operate under a magnetic field. The output voltage is stabilized by feedback. A feedback loop consists of an error amplifier, a voltage controlled oscillator and a driver circuit. The amplitude ratio of the transformer has dependence on the frequency, which is utilized to stabilize the output voltage. The low voltage power supply is investigated on the analogy of the high voltage power supply similarly incorporating the cerami...

  10. Active Microwave Metamaterials Incorporating Ideal Gain Devices

    Directory of Open Access Journals (Sweden)

    Hao Xin

    2010-12-01

    Full Text Available Incorporation of active devices/media such as transistors for microwave and gain media for optics may be very attractive for enabling desired low loss and broadband metamaterials. Such metamaterials can even have gain which may very well lead to new and exciting physical phenomena. We investigate microwave composite right/left-handed transmission lines (CRLH-TL incorporating ideal gain devices such as constant negative resistance. With realistic lumped element values, we have shown that the negative phase constant of this kind of transmission lines is maintained (i.e., left-handedness kept while gain can be obtained (negative attenuation constant of transmission line simultaneously. Possible implementation and challenging issues of the proposed active CRLH-TL are also discussed.

  11. Incorporating Database Design in Warnier Method

    Directory of Open Access Journals (Sweden)

    Donald Chand

    2000-11-01

    Full Text Available The Warnier method, a highly prescriptive program design approach for file-oriented solutions, has been criticized for its lack of a database design component. This paper addresses this weakness by incorporating a logical database design step in Warnier method. Specifically, the paper presents rules for transforming the information in a Warnier diagram into a set of relations. With this extension the Wamier method complements the entity-relationship approach for data analysis and logical database design.

  12. Iron incorporation and post-malaria anaemia.

    Directory of Open Access Journals (Sweden)

    Conor P Doherty

    Full Text Available BACKGROUND: Iron supplementation is employed to treat post-malarial anaemia in environments where iron deficiency is common. Malaria induces an intense inflammatory reaction that stalls reticulo-endothelial macrophagal iron recycling from haemolysed red blood cells and inhibits oral iron absorption, but the magnitude and duration of these effects are unclear. METHODOLOGY/PRINCIPAL FINDINGS: We examined the red blood cell incorporation of oral administered stable isotopes of iron and compared incorporation between age matched 18 to 36 months old children with either anaemia post-malaria (n = 37 or presumed iron deficiency anaemia alone (n = 36. All children were supplemented for 30 days with 2 mg/kg elemental iron as liquid iron sulphate and administered (57Fe and (58Fe on days 1 and 15 of supplementation respectively. (57Fe and(58Fe incorporation were significantly reduced (8% vs. 28%: p<0.001 and 14% vs. 26%: p = 0.045 in the malaria vs. non-malaria groups. There was a significantly greater haemoglobin response in the malaria group at both day 15 (p = 0.001 and 30 (p<0.000 with a regression analysis estimated greater change in haemoglobin of 7.2 g/l (s.e. 2.0 and 10.1 g/l (s.e. 2.5 respectively. CONCLUSION/SIGNIFICANCE: Post-malaria anaemia is associated with a better haemoglobin recovery despite a significant depressant effect on oral iron incorporation which may indicate that early erythropoetic iron need is met by iron recycling rather than oral iron. Supplemental iron administration is of questionable utility within 2 weeks of clinical malaria in children with mild or moderate anaemia.

  13. Incorporating OASIS into the Visiting Nurses Association.

    Science.gov (United States)

    Clark, L L

    1998-01-01

    Beginning in 1994, the Visiting Nurses Association, Western Pennsylvania, began to investigate incorporating an outcome measurement system within its organization for the purposes of marketing quality results, benchmarking achievements, and defining quality of care for both internal and external review groups. In the fall of 1995, this agency was accepted into the Outcome Based Quality Improvement (OBQI) Demonstration Project, also known as the Medicare Quality Assurance Project, which the Health Care Financing Administration has funded for the purpose of measuring clinical and utilization outcomes in the home care arena. This article reviews the processes the agency used to develop and incorporate the entire OBQI process into its systems, including the incorporation of the Outcome Assessment Information Set (OASIS). The OASIS is a set of outcome measurement questions developed by Dr. Peter Shaughnessy at the Center for Health Policy Research in Denver. The process also includes training of staff and development of forms, point-of-care software with a vendor, and plans of action for improving outcomes that have been quantified through OBQI efforts.

  14. Calcium incorporation in graphene oxide particles: A morphological, chemical, electrical, and thermal study

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Kelly L.S. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Instituto de Química, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos, 149, 21941-909 Rio de Janeiro (Brazil); Curti, Raphael V.; Araujo, Joyce R.; Landi, Sandra M.; Ferreira, Erlon H.M.; Neves, Rodrigo S.; Kuznetsov, Alexei; Sena, Lidia A. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Archanjo, Braulio S., E-mail: bsarchanjo@inmetro.gov.br [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Achete, Carlos A. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro (Brazil)

    2016-07-01

    Surface chemical modification and functionalization are common strategies used to provide new properties or functionalities to a material or to enhance existing ones. In this work, graphene oxide prepared using Hummers' method has been chemically modified with calcium ions by immersion in a calcium carbonate solution. Transmission electron microscopy analyses showed that graphene oxide (GO) and calcium incorporated graphene oxide have a morphology similar to an ultra-thin membrane composed of overlapping sheets. X-ray diffraction and Fourier-infrared spectroscopy show that calcium carbonate residue was completely removed by hydrochloric acid washes. Energy dispersive X-ray spectroscopy mapping showed spatially homogeneous calcium in Ca-incorporated graphene oxide sample after HCl washing. This Ca is mainly ionic according to X-ray photoelectron spectroscopy, and its incorporation promoted a small reduction in the graphene oxide structure, corroborated also by four-point probe measurements. A thermal study shows a remarkable increase in the GO stability with the presence of Ca{sup 2+} ions. - Highlights: • Graphene oxide has been chemically modified with Ca ions by immersion in a CaCO{sub 3} solution. • GO–Ca has morphology similar to an ultra-thin membrane composed of overlapping sheets. • CaCO{sub 3} residue was completely removed by acid washes, leaving only ionic calcium. • EDS maps show that Ca incorporation is spatially homogeneous in GO structure. • Thermal analyses show a remarkable increase in GO stability after Ca incorporation.

  15. Host-Pathogen Interactions : XXIV. Fragments Isolated from Suspension-Cultured Sycamore Cell Walls Inhibit the Ability of the Cells to Incorporate [C]Leucine into Proteins.

    Science.gov (United States)

    Yamazaki, N; Fry, S C; Darvill, A G; Albersheim, P

    1983-07-01

    A bioassay to measure the incorporation of [(14)C]leucine into acid-precipitable polymers of suspension-cultured sycamore (Acer pseudoplatanus L.) cells is described. Using this assay, cell wall fragments solubilized from sycamore cell walls by partial acid hydrolysis are shown to contain components that inhibit the incorporation of [(14)C]leucine into the acid-precipitable polymers. This inhibition was not attributable to a suppression of [(14)C]leucine uptake. The effectiveness of the wall fragments in inhibiting [(14)C]leucine incorporation was substantially relieved by plasmolysis of the cells. Fragments released from starch and citrus pectin are shown not to possess such inhibitory activities.

  16. Incorporation of codeine and metabolites into hair. Role of pigmentation.

    Science.gov (United States)

    Gygi, S P; Joseph, R E; Cone, E J; Wilkins, D G; Rollins, D E

    1996-04-01

    Xenobiotics circulating in the blood may become incorporated into growing hair. Melanin has affinity for many pharmacologically unrelated drugs and is responsible for the pigmentation in hair. To assess the role of pigmentation in the incorporation of drugs into hair, the distribution of codeine and its metabolites was studied in Sprague-Dawley (SD; white nonpigmented hair), Dark Agouti (DA; brown pigmented hair), and hooded Long-Evans (LE; both black pigmented and white nonpigmented hair) rats. Codeine was administered at a dose of 40 mg/kg/day i.p. for 5 days. Fourteen days after beginning the dosing protocol, hair was collected and analyzed for codeine, and its metabolite, morphine, by positive-ion chemical ionization GC/ion-trap MS. The plasma pharmacokinetics for codeine and morphine were also determined after a single 40 mg/kg injection (equivalent to first dose in 5-day dosing protocol) in all three strains of rats. Hair and plasma codeine and morphine concentrations were also determined after acid hydrolysis to evaluate the presence of glucuronide metabolites. Codeine concentrations in the hair of SD, DA, and pigmented LE hair were 0.98 +/- 0.10, 5.99 +/- 1.24, and 111.93 +/- 18.69 ng/mg hair, respectively; morphine concentrations were 0.34 +/- 0.04, 0.51 +/- 0.11, and 14.46 +/- 1.81 ng/mg hair, respectively; morphine glucuronide concentrations were 0.67 +/- 0.08, 1.04 +/- 0.37, and 13.80 +/- 3.60 ng/mg hair, respectively. Studies examining the in vitro binding of [3H] codeine and [3H]morphine to hair demonstrated both specific and nonspecific binding sites for codeine and morphine. Pigmented hair from LE rats possessed the greatest number of binding sites, white hair from SD rats contained the least, and brown hair from DA rats was intermediate. A time course study of codeine and its metabolites showed pigment-mediated differences in incorporation of codeine and metabolites within a few hours of drug administration. These data indicate that pigmented hair

  17. Enhanced bioactivity of glass ionomer cement by incorporating calcium silicates.

    Science.gov (United States)

    Chen, Song; Cai, Yixiao; Engqvist, Håkan; Xia, Wei

    2016-01-01

    Glass ionomer cements (GIC) are known as a non-bioactive dental cement. During setting the GIC have an acidic pH, driven by the acrylic acid component. It is a challenge to make GIC alkaline without disturbing its mechanical properties. One strategy was to add slowly reacting systems with an alkaline pH. The aim of the present study is to investigate the possibility of forming a bioactive dental material based on the combination of glass ionomer cement and calcium silicates. Two types of GIC were used as control. Wollastonite (CS also denoted β-CaSiO3) or Mineral Trioxide Aggregate (MTA) was incorporated into the 2 types of GIC. The material formulations' setting time, compressive strength, pH and bioactivity were compared between modified GIC and GIC control. Apatite crystals were found on the surfaces of the modified cements but not on the control GIC. The compressive strength of the cement remained with the addition of 20% calcium silicate or 20% MTA after one day immersion. In addition, the compressive strength of GIC modified with 20% MTA had been increased during the 14 d immersion (p < 0 .05).

  18. Postprandial fate of amino acids: adaptation to molecular forms

    NARCIS (Netherlands)

    Nolles, J.A.

    2006-01-01

    During the postprandial phase dietary proteins are digested to peptides and amino acids and absorbed. Once absorbed the peptides are further hydrolyzed to amino acids and transported to the tissues. These amino acids are largely incorporated into body proteins. Not all amino acids are, however,

  19. Studies on the effects of honey incorporation on quality and shelf life of aonla preserve

    Directory of Open Access Journals (Sweden)

    Saghir Ahmad

    2015-12-01

    Full Text Available Aonla is the richest sources of Vitamin C. The raw fruit, due to its high acidic nature and astringent taste is unacceptable to the consumers. Honey is a natural high energy sweetener with many medicinal values. Keeping in view the nutritional and therapeutic values of aonla fruit and honey, aonla preserve was prepared by incorporating 7.5 and 15% of honey into them. The quality of the products was evaluated based on the physicochemical (moisture, ash, pH, TSS, browning index and Vitamin C content, it was observed that the physicochemical characteristics of the aonla preserve improved upon incorporation of honey. There was improved retention of moisture content, increased ash content, reduced browning and reduced loss of Vitamin C due to incorporation of honey. The Vitamin C content in the aonla preserve (15% honey incorporation was 133.56 mg/100 g at the end of storage. The aonla preserve sample incorporated with 15% honey was nutritionally better as compared to samples incorporated with 7.5% honey due to its better Vitamin C retention, higher mineral content, tenderness and tangy taste. The yeast and the mould detected were few to count in the control sample. Shelf life of the product was 90 days.

  20. Manganese incorporation into ferroelectric lead titanate

    Science.gov (United States)

    Stoupin, Stanislav

    Substitution with 3d magnetic transition elements in ABO 3 ferroelectric perovskite host media is widely utilized to produce relaxor ferroelectrics. Many resulting solid solutions exhibit magnetoelectric properties affected by concentration levels of the introduced magnetic ions. For conventional material preparation techniques such as firing of mechanically mixed oxides, incorporation is often limited by 5 mol% concentration level. Doping at higher concentrations requires introduction of other substituents to compensate charge within the unit cell to promote formation of the perovskite phase. In contrast, molecular mixing of precursor materials at the initial phase of preparation procedure offers an advantage of achieving higher incorporation levels of the 3d elements without additional charge-compensating ions. Presented in this thesis is a new sol-gel procedure utilized for high level incorporation of 3d magnetic ions into ferroelectric lead titanate. The technique was applied to produce PbTi1-xMnxO 3 solid solution, a perovskite system promising for high degree of magnetoelectric coupling. Concentration dependent studies were performed to characterize structural, thermal, ferroelectric and magnetic properties of the material. The solubility limit of Mn has been found to be 20 mol% and the material remains tetragonally distorted. X-ray Absorption Spectroscopy confirms that local structural environment of Mn, Ti, and Pb is consistent with tetragonal symmetry of the unit cell. Increase in Mn concentration leads to reduction in melting point, broadening of the ferroelectric transition, reduction of the transition temperature and increase in dielectric constant of the material. At the solubility limit the system was found to be ferromagnetic below 50 K.

  1. Diagnosis of Hunter's syndrome carriers; radioactive sulphate incorporation into fibroblasts in the presence of fructose 1-phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Toennesen, T.; Lykkelund, C.; Guettler, F.

    1982-01-01

    Mutual correction of co-cultivated fibroblasts from patients with Hunter's and Hurler's syndrome could be inhibited by either fructose 1-phosphate or mannose 6-phosphate. In the presence of fructose 1-phosphate a 50% mixture of fibroblasts from a patient with Hunter's syndrome and a normal homozygous individual showed an increased /sup 35/S-sulphate incorporation into acid mucopolysaccharides. When fibroblast cultures from one obligate and two possible carriers of Hunter's syndrome were tested for /sup 35/S-sulphate incorporation, the cultures showed either twice the normal /sup 35/S-sulphate incorporation into acid mucopolysaccharides in the presence of fructose 1-phosphate or an abnormally high incorporation in the presence as well as in the absence of the sugar phosphate.

  2. Incorporating sustainability into accounting curricula

    DEFF Research Database (Denmark)

    Hazelton, James; Haigh, Matthew

    2010-01-01

    This paper chronicles the journey of two projects that sought to incorporate principles of sustainable development into predominantly technical postgraduate accounting curricula. The design and delivery of the projects were informed by Freirian principles of praxis and critical empowerment....... The first author introduced sustainability-related material into a core technical accounting unit and created an elective unit. The second author participated with students to evaluate critically social reports of employers, current and potential. In terms of an objective of bringing reflexivity...... as vocational skills) add to the difficulties for sustainability in penetrating already overcrowded curricula....

  3. Security Risk Scoring Incorporating Computers' Environment

    Directory of Open Access Journals (Sweden)

    Eli Weintraub

    2016-04-01

    Full Text Available A framework of a Continuous Monitoring System (CMS is presented, having new improved capabilities. The system uses the actual real-time configuration of the system and environment characterized by a Configuration Management Data Base (CMDB which includes detailed information of organizational database contents, security and privacy specifications. The Common Vulnerability Scoring Systems' (CVSS algorithm produces risk scores incorporating information from the CMDB. By using the real updated environmental characteristics the system enables achieving accurate scores compared to existing practices. Framework presentation includes systems' design and an illustration of scoring computations.

  4. Incorporating sustainability into accounting curricula

    DEFF Research Database (Denmark)

    Hazelton, James; Haigh, Matthew

    2010-01-01

    This paper chronicles the journey of two projects that sought to incorporate principles of sustainable development into predominantly technical postgraduate accounting curricula. The design and delivery of the projects were informed by Freirian principles of praxis and critical empowerment....... The first author introduced sustainability-related material into a core technical accounting unit and created an elective unit. The second author participated with students to evaluate critically social reports of employers, current and potential. In terms of an objective of bringing reflexivity...... as vocational skills) add to the difficulties for sustainability in penetrating already overcrowded curricula....

  5. Incorporation of noble metals into aerogels

    Science.gov (United States)

    Hair, Lucy M.; Sanner, Robert D.; Coronado, Paul R.

    1998-01-01

    Aerogels or xerogels containing atomically dispersed noble metals for applications such environmental remediation. New noble metal precursors, such as Pt--Si or Pd(Si--P).sub.2, have been created to bridge the incompatibility between noble metals and oxygen, followed by their incorporation into the aerogel or xerogel through sol-gel chemistry and processing. Applications include oxidation of hydrocarbons and reduction of nitrogen oxide species, complete oxidation of volatile organic carbon species, oxidative membranes for photocatalysis and partial oxidation for synthetic applications.

  6. Flow cytometric assessment of specific leucine incorporation in the open Mediterranean

    Science.gov (United States)

    Talarmin, A.; van Wambeke, F.; Catala, P.; Courties, C.; Lebaron, P.

    2011-02-01

    The surface of the Mediterranean Sea is a low-phosphate-low-chlorophyll marine area where marine heterotrophic prokaryotes significantly contribute to the biogeochemical cycles of all biogenic elements such as carbon, notably through the mineralization of dissolved organic compounds. Cell-specific leucine incorporation rates were determined in early summer in the open stratified Mediterranean Sea. The bulk leucine incorporation rate was on average 5 ± 4 pmol leu l-1 h-1 (n=30). Cell-specific 3H-leucine incorporation rates were assayed using flow cytometry coupled to cell sorting. Heterotrophic prokaryotes (Hprok) were divided into cytometric groups according to their side scatter and green fluorescence properties: high nucleic acid containing cells (HNA) with high scatter (HNA-hs) and low scatter (HNA-ls) and low nucleic acid containing cells (LNA). Cell-specific leucine incorporation rates of these cytometric groups ranged from 2 to 54, 0.9 to 11, and 1 to 12 × 10-21 mol cell-1 h-1, respectively. LNA cells represented 45 to 63% of the Hprok abundance, and significantly contributed to the bulk leucine incorporation rates, from 12 to 43%. HNA/LNA ratios of cell-specific leucine incorporation were on average 2.0 ± 0.7 (n=30). In surface layers (from 0 m down to the deep chlorophyll depth, DCM), cell-specific rates of HNA-hs were elevated (7 and 13 times greater than LNA and HNA-ls, respectively). Nevertheless, on average HNA-hs (26%) and LNA (27%) equally contributed to the bulk leucine incorporation in these layers. Prochlorococcus cells were easily sorted near the DCM and displayed cell-specific leucine incorporation rates ranging from 3 to 55 × 10-21 mol leu cell-1 h-1, i.e. as high as HNA-hs'. These sorted groups could therefore be defined as key-players in the process of leucine incorporation into proteins. The mixotrophic features of certain photosynthetic prokaryotes and the high contribution of LNA cells to leucine incorporation within the microbial

  7. Flow cytometric assessment of specific leucine incorporation in the open Mediterranean

    Directory of Open Access Journals (Sweden)

    A. Talarmin

    2011-02-01

    Full Text Available The surface of the Mediterranean Sea is a low-phosphate-low-chlorophyll marine area where marine heterotrophic prokaryotes significantly contribute to the biogeochemical cycles of all biogenic elements such as carbon, notably through the mineralization of dissolved organic compounds. Cell-specific leucine incorporation rates were determined in early summer in the open stratified Mediterranean Sea. The bulk leucine incorporation rate was on average 5 ± 4 pmol leu l−1 h−1 (n=30. Cell-specific 3H-leucine incorporation rates were assayed using flow cytometry coupled to cell sorting. Heterotrophic prokaryotes (Hprok were divided into cytometric groups according to their side scatter and green fluorescence properties: high nucleic acid containing cells (HNA with high scatter (HNA-hs and low scatter (HNA-ls and low nucleic acid containing cells (LNA. Cell-specific leucine incorporation rates of these cytometric groups ranged from 2 to 54, 0.9 to 11, and 1 to 12 × 10-21 mol cell−1 h−1, respectively. LNA cells represented 45 to 63% of the Hprok abundance, and significantly contributed to the bulk leucine incorporation rates, from 12 to 43%. HNA/LNA ratios of cell-specific leucine incorporation were on average 2.0 ± 0.7 (n=30. In surface layers (from 0 m down to the deep chlorophyll depth, DCM, cell-specific rates of HNA-hs were elevated (7 and 13 times greater than LNA and HNA-ls, respectively. Nevertheless, on average HNA-hs (26% and LNA (27% equally contributed to the bulk leucine incorporation in these layers. Prochlorococcus cells were easily sorted near the DCM and displayed cell-specific leucine incorporation rates ranging from 3 to 55 × 10-21 mol leu cell−1 h−1, i.e. as high as HNA-hs'. These sorted groups could therefore be defined as key-players in the process of leucine incorporation into proteins. The

  8. Incorporating Geospatial Technology into Teacher Professional Development

    Science.gov (United States)

    Sproles, E. A.; Songer, L.

    2009-12-01

    The need for students to think spatially and use geospatial technologies is becoming more critical as these tools and concepts are increasingly incorporated into a broad range of occupations and academic disciplines. Geospatial Teaching Across the Curriculum (Geo-STAC) is a collaborative program that provides high school teachers with mentored professional development workshops in geospatial thought and technology. The seminars, led by community college faculty, give high school teachers the ability to incorporate geospatial technology into coursework across the curriculum — in Science, Technology, Engineering, and Math (STEM) and non-STEM disciplines. Students participating in the hands-on lessons gain experience in web-based and desktop Geographic Information Systems (GIS). The goals of the workshop are for teachers to: (1) understand the importance of geospatial thinking; (2) learn how to employ geospatial thinking in each discipline; (3) learn about geospatial technologies; (4) develop a Web-based GIS lesson; and, (5) implement a Web-based GIS lesson. Additionally, Geo-STAC works with high school students so that they: (1) understand the importance of geospatial technologies and careers in future job markets; (2) learn how to use Web-based GIS to solve problems; and, (3) visit the community college GIS lab and experience using desktop GIS. Geo-STAC actively disseminates this collaborative model to colleges to community colleges and high schools across the country.

  9. Incorporating intelligence into structured radiology reports

    Science.gov (United States)

    Kahn, Charles E.

    2014-03-01

    The new standard for radiology reporting templates being developed through the Integrating the Healthcare Enterprise (IHE) and DICOM organizations defines the storage and exchange of reporting templates as Hypertext Markup Language version 5 (HTML5) documents. The use of HTML5 enables the incorporation of "dynamic HTML," in which documents can be altered in response to their content. HTML5 documents can employ JavaScript, the HTML Document Object Model (DOM), and external web services to create intelligent reporting templates. Several reporting templates were created to demonstrate the use of scripts to perform in-template calculations and decision support. For example, a template for adrenal CT was created to compute contrast washout percentage from input values of precontrast, dynamic postcontrast, and delayed adrenal nodule attenuation values; the washout value can used to classify an adrenal nodule as a benign cortical adenoma. Dynamic templates were developed to compute volumes and apply diagnostic criteria, such as those for determination of internal carotid artery stenosis. Although reporting systems need not use a web browser to render the templates or their contents, the use of JavaScript creates innumerable opportunities to construct highly sophisticated HTML5 reporting templates. This report demonstrates the ability to incorporate dynamic content to enhance the use of radiology reporting templates.

  10. Incorporating Experience Curves in Appliance Standards Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit

    2011-10-31

    The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.

  11. Strategies for incorporation of chia (Salvia hispanica L.) in frankfurters as a health-promoting ingredient.

    Science.gov (United States)

    Pintado, T; Herrero, A M; Jiménez-Colmenero, F; Ruiz-Capillas, C

    2016-04-01

    Different strategies were examined for incorporation of chia flour (10%) and olive oil to improve the fat content in frankfurters. Nutritional composition, technological properties, sensory and microbiological analyses were studied as affected by the strategy used and by chilling storage. Chia increased total dietary fibre (98% insoluble dietary fibre) and minerals (K, Mg, Ca, Mn) irrespective of the incorporation strategy. Fat and energy content reduction (>26%) were achieved in all frankfurters reformulated with chia and olive oil. Chia addition increased linolenic acid and reduced processing and purge in all samples. Lightness and redness of frankfurters were affected by the presence of chia, but there was no clear evidence of influence by the mode of addition. Frankfurter texture was influenced by the strategy used to incorporate chia and olive oil and by chilling storage. Samples were judged acceptable and contained low microorganism levels. Frankfurters containing chia were suitable for labelling with certain nutrition and health claims. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. INCORPORATING DYNAMIC 3D SIMULATION INTO PRA

    Energy Technology Data Exchange (ETDEWEB)

    Steven R Prescott; Curtis Smith

    2011-07-01

    Through continued advancement in computational resources, development that was previously done by trial and error production is now performed through computer simulation. These virtual physical representations have the potential to provide accurate and valid modeling results and are being used in many different technical fields. Risk assessment now has the opportunity to use 3D simulation to improve analysis results and insights, especially for external event analysis. By using simulations, the modeler only has to determine the likelihood of an event without having to also predict the results of that event. The 3D simulation automatically determines not only the outcome of the event, but when those failures occur. How can we effectively incorporate 3D simulation into traditional PRA? Most PRA plant modeling is made up of components with different failure modes, probabilities, and rates. Typically, these components are grouped into various systems and then are modeled together (in different combinations) as a “system” with logic structures to form fault trees. Applicable fault trees are combined through scenarios, typically represented by event tree models. Though this method gives us failure results for a given model, it has limitations when it comes to time-based dependencies or dependencies that are coupled to physical processes which may themselves be space- or time-dependent. Since, failures from a 3D simulation are naturally time related, they should be used in that manner. In our simulation approach, traditional static models are converted into an equivalent state diagram representation with start states, probabilistic driven movements between states and terminal states. As the state model is run repeatedly, it converges to the same results as the PRA model in cases where time-related factors are not important. In cases where timing considerations are important (e.g., when events are dependent upon each other), then the simulation approach will typically

  13. Incorporating immigrant flows into microsimulation models.

    Science.gov (United States)

    Duleep, Harriet Orcutt; Dowhan, Daniel J

    2008-01-01

    Building on the research on immigrant earnings reviewed in the first article of this series, "Research on Immigrant Earnings," the preceding article, "Adding Immigrants to Microsimulation Models," linked research results to various issues essential for incorporating immigrant earnings into microsimulation models. The discussions of that article were in terms of a closed system. That is, it examined a system in which immigrant earnings and emigration are forecast for a given population represented in the base sample in the microsimulation model. This article, the last in the series, addresses immigrant earnings projections for open systems--microsimulation models that include projections of future immigration. The article suggests a simple method to project future immigrants and their earnings. Including the future flow of immigrants in microsimulation models can dramatically affect the projected Social Security benefits of some groups.

  14. Incorporating User-oriented Security into CC

    DEFF Research Database (Denmark)

    Sharp, Robin

    2009-01-01

    Current versions of the Common Criteria concentrate very heavily on technical security issues which are relevant for the design of secure systems. This approach largely ignores a number of questions which can have great significance for whether or not the system can be operated securely...... in an environment which contains not only other computer systems, but also human users. A case study involving the design of a secure medical instrumentation system will be used to illustrate the problems involved in incorporating user requirements into a secure design, so that system, when implemented, will help...... users to understand whether they are operating the system in a secure manner, thus avoiding user-related pitfalls such as leaking of confidential data as a result of inappropriate input, loss of patient privacy, inappropriate user reactions due to slow system response, or other similar threats...

  15. Control devices incorporated with shape memory alloy

    Institute of Scientific and Technical Information of China (English)

    Xue Suduo; Li Xiongyan

    2007-01-01

    Shape Memory Alloy (SMA) is a type of material that offers some unique characteristics for use in devices for vibration control applications. Based on SMA's material properties, four types of control devices that incorporate NiTi SMA wires are introduced in this paper, which include three types of dampers (SMA damper, SMA-MR damper and SMA-friction damper) and one kind of isolation bearing (SMA-rubber bearing). Mechanical models of these devices and their experimental verifications are presented. To investigate the control performance of these devices, the SMA-MR damper and SMA-rubber bearing are applied to structures. The results show that the control devices could be effective in reducing the seismic response of structures.

  16. Incorporation of ITC into Colombian businesses

    Directory of Open Access Journals (Sweden)

    César A. Ortega Ruiz

    2014-07-01

    Full Text Available This review sought to provide general guidelines on how technologies have been incorporated into the information and communications business in Colombia. It presents a brief description of the stages through which the communications media has passed and its relationship with companies from its beginnings to the present day. The main statistics associated with the levels of adoption of ICT by the Colombian company are presented, showing the existence of a strong digital divide, especially by domestic micro-companies, which still have low adoption levels. However, this situation can be seen as an opportunity for the implementation of enterprises associated with this sector of the economy that has become one of the fastest growing in Colombia and in the world in recent years.

  17. Active containment systems incorporating modified pillared clays

    Energy Technology Data Exchange (ETDEWEB)

    Lundie, P. [Envirotech (Scotland) Ltd., Aberdeen (United Kingdom)]|[Environmental Resource Industries Disposal Pty Ltd., Perth (Australia); McLeod, N. [Envirotreat Ltd., Kingswinford (United Kingdom)

    1997-12-31

    The application of treatment technologies in active containment systems provides a more advanced and effective method for the remediation of contaminated sites. These treatment technologies can be applied in permeable reactive walls and/or funnel and gate systems. The application of modified pillared clays in active containment systems provides a mechanism for producing permeable reactive walls with versatile properties. These pillared clays are suitably modified to incorporate reactive intercalatants capable of reacting with both a broad range of organic pollutants of varying molecular size, polarity and reactivity. Heavy metals can be removed from contaminated water by conventional ion-exchange and other reactive processes within the clay structure. Complex contamination problems can be addressed by the application of more than one modified clay on a site specific basis. This paper briefly describes the active containment system and the structure/chemistry of the modified pillared clay technology, illustrating potential applications of the in-situ treatment process for contaminated site remediation.

  18. Radiation Shielding Materials and Containers Incorporating Same

    Energy Technology Data Exchange (ETDEWEB)

    Mirsky, Steven M.; Krill, Stephen J.; and Murray, Alexander P.

    2005-11-01

    An improved radiation shielding material and storage systems for radioactive materials incorporating the same. The PYRolytic Uranium Compound (''PYRUC'') shielding material is preferably formed by heat and/or pressure treatment of a precursor material comprising microspheres of a uranium compound, such as uranium dioxide or uranium carbide, and a suitable binder. The PYRUC shielding material provides improved radiation shielding, thermal characteristic, cost and ease of use in comparison with other shielding materials. The shielding material can be used to form containment systems, container vessels, shielding structures, and containment storage areas, all of which can be used to house radioactive waste. The preferred shielding system is in the form of a container for storage, transportation, and disposal of radioactive waste. In addition, improved methods for preparing uranium dioxide and uranium carbide microspheres for use in the radiation shielding materials are also provided.

  19. [Effectiveness of incorporating a quality management system].

    Science.gov (United States)

    Seki, Akira; Hankins, Raleigh W; Miya, Tetsumasa

    2010-01-01

    In 2003, the ISO 15189 international standardization program on the quality and competence of the clinical reference laboratory was introduced. To date, 46 facilities have committed themselves to providing a higher level of medical service by incorporating a quality management system (QMS) and acquiring accreditation. QMS is defined as "setting up a policy and goals pertaining to quality, and adopting an appropriate system," and is a scheme that includes all managerial and technical factors that can affect test results. Regarding the Health Sciences Research Institute Group, 4 facilities have previously received the accreditation described above, but in the process of implementing the QMS, a number of problems have been identified. Here, we report on the effectiveness of adopting such a QMS based on the results of employee questionnaires, internal audits, customer complaint analyses, and external audits by the Japan Accreditation Board for Conformity Assessment (JAB), the official inspection body for accreditation.

  20. Incorporation of RAM techniques into simulation modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, S.C. Jr.; Haire, M.J.; Schryver, J.C.

    1995-07-01

    This work concludes that reliability, availability, and maintainability (RAM) analytical techniques can be incorporated into computer network simulation modeling to yield an important new analytical tool. This paper describes the incorporation of failure and repair information into network simulation to build a stochastic computer model represents the RAM Performance of two vehicles being developed for the US Army: The Advanced Field Artillery System (AFAS) and the Future Armored Resupply Vehicle (FARV). The AFAS is the US Army`s next generation self-propelled cannon artillery system. The FARV is a resupply vehicle for the AFAS. Both vehicles utilize automation technologies to improve the operational performance of the vehicles and reduce manpower. The network simulation model used in this work is task based. The model programmed in this application requirements a typical battle mission and the failures and repairs that occur during that battle. Each task that the FARV performs--upload, travel to the AFAS, refuel, perform tactical/survivability moves, return to logistic resupply, etc.--is modeled. Such a model reproduces a model reproduces operational phenomena (e.g., failures and repairs) that are likely to occur in actual performance. Simulation tasks are modeled as discrete chronological steps; after the completion of each task decisions are programmed that determine the next path to be followed. The result is a complex logic diagram or network. The network simulation model is developed within a hierarchy of vehicle systems, subsystems, and equipment and includes failure management subnetworks. RAM information and other performance measures are collected which have impact on design requirements. Design changes are evaluated through ``what if`` questions, sensitivity studies, and battle scenario changes.

  1. Fluoride removal using lanthanum incorporated chitosan beads.

    Science.gov (United States)

    Bansiwal, Amit; Thakre, Dilip; Labhshetwar, Nitin; Meshram, Siddharth; Rayalu, Sadhana

    2009-11-01

    Highly selective material based on naturally occurring biomaterial namely chitosan has been designed for the defluoridation of water. Lanthanum incorporated chitosan beads (LCB) were prepared using precipitation method. The synthesis was optimized by varying different synthesis parameters namely lanthanum loading, complexation and precipitation time, strength of ammonia solution used for precipitation, drying time, etc. Lanthanum incorporated chitosan beads were characterized using SEM, FTIR, XRD and EDX. Surface area of LCB was observed to be 2.76 m(2)g(-1). The equilibrium adsorption data fitted well to Langmuir adsorption isotherm and showing maximum fluoride adsorption capacity of 4.7 mg g(-1) with negligible lanthanum release. Kinetic study reveals that adsorption of fluoride is fast and follows pseudo-first-order kinetics. The effect of pH was also studied and the best efficiency was observed at pH 5. Presence of sulphate, nitrate and chloride marginally affected the removal efficiency, however drastic reduction in fluoride uptake was observed in the presence of carbonate and bicarbonate. Negative value of change in free energy (DeltaG degrees) and positive value of change in entropy (DeltaS degrees) suggest the adsorption of fluoride by LCB is feasible and spontaneous process. Positive value of change in enthalpy (DeltaH degrees) suggests the process of fluoride adsorption is endothermic in nature. Regeneration study reveals that 1M ammonium chloride solution appears to be the promising regeneration media showing 81.22% regeneration. The adsorption capacity of LCB was similar in fluoride-contaminated ground water collected from Dhar district of Madhya Pradesh, India, as compared to simulated water.

  2. Quantification of N-acetylcysteamine activated methylmalonate incorporation into polyketide biosynthesis

    Directory of Open Access Journals (Sweden)

    Stephan Klopries

    2013-04-01

    Full Text Available Polyketides are biosynthesized through consecutive decarboxylative Claisen condensations between a carboxylic acid and differently substituted malonic acid thioesters, both tethered to the giant polyketide synthase enzymes. Individual malonic acid derivatives are typically required to be activated as coenzyme A-thioesters prior to their enzyme-catalyzed transfer onto the polyketide synthase. Control over the selection of malonic acid building blocks promises great potential for the experimental alteration of polyketide structure and bioactivity. One requirement for this endeavor is the supplementation of the bacterial polyketide fermentation system with tailored synthetic thioester-activated malonates. The membrane permeable N-acetylcysteamine has been proposed as a coenzyme A-mimic for this purpose. Here, the incorporation efficiency into different polyketides of N-acetylcysteamine activated methylmalonate is studied and quantified, showing a surprisingly high and transferable activity of these polyketide synthase substrate analogues in vivo.

  3. Ribosomal Synthesis of Peptides with Multiple β-Amino Acids.

    Science.gov (United States)

    Fujino, Tomoshige; Goto, Yuki; Suga, Hiroaki; Murakami, Hiroshi

    2016-02-17

    The compatibility of β-amino acids with ribosomal translation was studied for decades, but it has been still unclear whether the ribosome can accept various β-amino acids, and whether the ribosome can introduce multiple β-amino acids in a peptide. In the present study, by using the Escherichia coli reconstituted cell-free translation system with a reprogramed genetic code, we screened β-amino acids that give high single incorporation efficiency and used them to synthesize peptides containing multiple β-amino acids. The experiments of single β-amino acid incorporation into a peptide revealed that 13 β-amino acids are compatible with ribosomal translation. Six of the tested β-amino acids (βhGly, l-βhAla, l-βhGln, l-βhPhg, l-βhMet, and d-βhPhg) showed high incorporation efficiencies, and seven (l-βhLeu, l-βhIle, l-βhAsn, l-βhPhe, l-βhLys, d-βhAla, and d-βhLeu) showed moderate incorporation efficiencies; whereas no full-length peptide was produced using other β-amino acids (l-βhPro, l-βhTrp, and l-βhGlu). Subsequent double-incorporation experiments using β-amino acids with high single incorporation efficiency revealed that elongation of peptides with successive β-amino acids is prohibited. Efficiency of the double-incorporation of the β-amino acids was restored by the insertion of Tyr or Ile between the two β-amino acids. On the basis of these experiments, we also designed mRNA sequences of peptides, and demonstrated the ribosomal synthesis of peptides containing different types of β-amino acids at multiple positions.

  4. A New Achiral Linker Reagent for the Incorporation of Multiple Amino Groups Into Oligonucleotides

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to a new functionalized achiral linker reagent for incorporating multiple primary amino groups or reporter groups into oligonucleotides following the phosphoramidite methodology. It is possible to substitute any ribodeoxynucleotide, deoxynucleotide, or nucleotide wit......, to a method for preparing a labelled oligonucleotide, and to the use of the labelled oligonucleotide as hybridisation probe, in polymerase chain reactions (PCR), in nucleic acid sequencing, in cloning recombinant DNA and $i(in vitro) mutagenesis....

  5. Revised mechanism of D-alanine incorporation into cell wall polymers in Gram-positive bacteria.

    Science.gov (United States)

    Reichmann, Nathalie T; Cassona, Carolina Picarra; Gründling, Angelika

    2013-09-01

    Teichoic acids (TAs) are important for growth, biofilm formation, adhesion and virulence of Gram-positive bacterial pathogens. The chemical structures of the TAs vary between bacteria, though they typically consist of zwitterionic polymers that are anchored to either the peptidoglycan layer as in the case of wall teichoic acid (WTA) or the cell membrane and named lipoteichoic acid (LTA). The polymers are modified with D-alanines and a lack of this decoration leads to increased susceptibility to cationic antimicrobial peptides. Four proteins, DltA-D, are essential for the incorporation of d-alanines into cell wall polymers and it has been established that DltA transfers D-alanines in the cytoplasm of the cell onto the carrier protein DltC. However, two conflicting models have been proposed for the remainder of the mechanism. Using a cellular protein localization and membrane topology analysis, we show here that DltC does not traverse the membrane and that DltD is anchored to the outside of the cell. These data are in agreement with the originally proposed model for D-alanine incorporation through a process that has been proposed to proceed via a D-alanine undecaprenyl phosphate membrane intermediate. Furthermore, we found that WTA isolated from a Staphylococcus aureus strain lacking LTA contains only a small amount of D-alanine, indicating that LTA has a role, either direct or indirect, in the efficient D-alanine incorporation into WTA in living cells.

  6. Coupling Bioorthogonal Chemistries with Artificial Metabolism: Intracellular Biosynthesis of Azidohomoalanine and Its Incorporation into Recombinant Proteins

    Directory of Open Access Journals (Sweden)

    Ying Ma

    2014-01-01

    Full Text Available In this paper, we present a novel, “single experiment” methodology based on genetic engineering of metabolic pathways for direct intracellular production of non-canonical amino acids from simple precursors, coupled with expanded genetic code. In particular, we engineered the intracellular biosynthesis of L-azidohomoalanine from O-acetyl-L-homoserine and NaN3, and achieved its direct incorporation into recombinant target proteins by AUG codon reassignment in a methionine-auxotroph E. coli strain. In our system, the host’s methionine biosynthetic pathway was first diverted towards the production of the desired non-canonical amino acid by exploiting the broad reaction specificity of recombinant pyridoxal phosphate-dependent O-acetylhomoserine sulfhydrylase from Corynebacterium glutamicum. Then, the expression of the target protein barstar, accompanied with efficient L-azidohomoalanine incorporation in place of L-methionine, was accomplished. This work stands as proof-of-principle and paves the way for additional work towards intracellular production and site-specific incorporation of biotechnologically relevant non-canonical amino acids directly from common fermentable sources.

  7. PGA-incorporated collagen: Toward a biodegradable composite scaffold for bone-tissue engineering.

    Science.gov (United States)

    Toosi, Shirin; Naderi-Meshkin, Hojjat; Kalalinia, Fatemeh; Peivandi, Mohammad Taghi; HosseinKhani, Hossein; Bahrami, Ahmad Reza; Heirani-Tabasi, Asieh; Mirahmadi, Mahdi; Behravan, Javad

    2016-08-01

    Nowadays composite scaffolds based on synthetic and natural biomaterials have got attention to increase healing of non-union bone fractures. To this end, different aspects of collagen sponge incorporated with poly(glycolic acid) (PGA) fiber were investigated in this study. Collagen solution (6.33 mg/mL) with PGA fibers (collagen/fiber ratio [w/w]: 4.22, 2.11, 1.06, 0.52) was freeze-dried, followed by dehydrothermal cross-linking to obtain collagen sponge incorporating PGA fibers. Properties of scaffold for cell viability, proliferation, and differentiation of mesenchymal stem cells (MSCs) were evaluated. Scanning electron microscopy showed that collagen sponge exhibited an interconnected pore structure with an average pore size of 190 μm, irrespective of PGA fiber incorporation. The collagen-PGA sponge was superior to the original collagen sponge in terms of the initial attachment, proliferation rate, and osteogenic differentiation of the bone marrow-MSCs (BM-MSC). The shrinkage of sponges during cell culture was significantly suppressed by fiber incorporation. Incorporation of PGA fiber is a simple and promising way to reinforce collagen sponge without impairing biocompatibility. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2020-2028, 2016.

  8. Incorporation of ovalbumin into ISCOMs and related colloidal particles prepared by the lipid film hydration method.

    Science.gov (United States)

    Demana, Patrick H; Davies, Nigel M; Berger, Bianca; Rades, Thomas

    2004-07-08

    The aim of this study was to investigate the incorporation of a model antigen, fluorescently labelled ovalbumin (FITC-OVA), into various colloidal particles including immune stimulating complexes (ISCOMs), liposomes, ring and worm-like micelles, lamellae and lipidic/layered structures that are formed from various combinations of the triterpene saponin Quil A, cholesterol and phosphatidylethanolamine (PE) following hydration of PE/cholesterol lipid films with aqueous solutions of Quil A. Colloidal dispersions of these three components were also prepared by the dialysis method for comparison. FITC-OVA was conjugated with palmitic acid (P) and PE to produce P-FITC-OVA and PE-FITC-OVA, respectively. Both P-FITC-OVA and PE-FITC-OVA could be incorporated in all colloidal structures whereas FITC-OVA was incorporated only into liposomes. The incorporation of PE-FITC-OVA into all colloidal structures was significantly higher than P-FITC-OVA (P < 0.05). The degree of incorporation of protein was in the order: ring and worm-like micelles < liposomes and lipidic/layered structures < ISCOMs and lamellae. The incorporation of protein into the various particles prepared by the lipid film hydration method was similar to those for colloidal particles prepared by the dialysis method (provided both methods lead to the formation of the same colloidal structures). In the case of different colloidal structures arising due to the preparation method, differences in encapsulation efficiency were found (P < 0.05) for formulations with the same polar lipid composition. This study demonstrates that the various colloidal particles formed as a result of hydrating PE/cholesterol lipid films with different amounts of Quil A are capable of incorporating antigen, provided it is amphipathic. Some of these colloidal particles may be used as effective vaccine delivery systems.

  9. 75 FR 17737 - Industrial Economics, Incorporated; Transfer of Data

    Science.gov (United States)

    2010-04-07

    ... AGENCY Industrial Economics, Incorporated; Transfer of Data AGENCY: Environmental Protection Agency (EPA... Economics, Incorporated in accordance with 40 CFR 2.307(h)(3) and 2.308(i)(2). Industrial Economics... enable Industrial Economics, Incorporated to fulfill the obligations of the contract. DATES:...

  10. 48 CFR 1952.102-2 - Incorporation in full text.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Incorporation in full text... Clauses 1952.102-2 Incorporation in full text. All IAAR provisions and clauses shall be incorporated in solicitations and/or contracts in full text....

  11. 48 CFR 2852.102-270 - Incorporation in full text.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Incorporation in full text... 2852.102-270 Incorporation in full text. JAR provisions or clauses shall be incorporated in solicitations and contracts in full text....

  12. 46 CFR 193.01-3 - Incorporation by reference.

    Science.gov (United States)

    2010-10-01

    ... PROTECTION EQUIPMENT Application § 193.01-3 Incorporation by reference. (a) Certain material is incorporated... Specification for International Shore Connections for Marine Fire Applications, incorporation by reference approved for § 193.10-10. (2) (c) National Fire Protection Association (NFPA), 1 Batterymarch Park,...

  13. Incorporating Student Activities into Climate Change Education

    Science.gov (United States)

    Steele, H.; Kelly, K.; Klein, D.; Cadavid, A. C.

    2013-12-01

    Under a NASA grant, Mathematical and Geospatial Pathways to Climate Change Education, students at California State University, Northridge integrated Geographic Information Systems (GIS), remote sensing, satellite data technologies, and climate modelling into the study of global climate change under a Pathway for studying the Mathematics of Climate Change (PMCC). The PMCC, which is an interdisciplinary option within the BS in Applied Mathematical Sciences, consists of courses offered by the departments of Mathematics, Physics, and Geography and is designed to prepare students for careers and Ph.D. programs in technical fields relevant to global climate change. Under this option students are exposed to the science, mathematics, and applications of climate change science through a variety of methods including hands-on experience with computer modeling and image processing software. In the Geography component of the program, ESRI's ArcGIS and ERDAS Imagine mapping, spatial analysis and image processing software were used to explore NASA satellite data to examine the earth's atmosphere, hydrosphere and biosphere in areas that are affected by climate change or affect climate. These technology tools were incorporated into climate change and remote sensing courses to enhance students' knowledge and understanding of climate change through hands-on application of image processing techniques to NASA data. Several sets of exercises were developed with specific learning objectives in mind. These were (1) to increase student understanding of climate change and climate change processes; (2) to develop student skills in understanding, downloading and processing satellite data; (3) to teach remote sensing technology and GIS through applications to climate change; (4) to expose students to climate data and methods they can apply to solve real world problems and incorporate in future research projects. In the Math and Physics components of the course, students learned about

  14. Mechanism of Synergistic Inhibition of Listeria monocytogenes Growth by Lactic Acid, Monolaurin, and Nisin▿

    OpenAIRE

    Tokarskyy, Oleksandr; Marshall, Douglas L.

    2008-01-01

    The combined lactic acid, monolaurin, and nisin effects on time-to-detection (optical density at 600 nm) extension were greater (P < 0.05) than any single or paired combination effect, which demonstrates a synergistic interaction among the antimicrobials. Monolaurin exposure caused C12:0 cell membrane incorporation. Lactic acid caused increased monolaurin C12:0 membrane incorporation, while nisin had no influence. We postulate that lactic acid-enhanced monolaurin C12:0 incorporation into the ...

  15. Mechanism of synergistic inhibition of Listeria monocytogenes growth by lactic acid, monolaurin, and nisin.

    Science.gov (United States)

    Tokarskyy, Oleksandr; Marshall, Douglas L

    2008-12-01

    The combined lactic acid, monolaurin, and nisin effects on time-to-detection (optical density at 600 nm) extension were greater (P Monolaurin exposure caused C12:0 cell membrane incorporation. Lactic acid caused increased monolaurin C12:0 membrane incorporation, while nisin had no influence. We postulate that lactic acid-enhanced monolaurin C12:0 incorporation into the cell membrane increased membrane fluidity resulting in increased nisin activity.

  16. Mechanism of Synergistic Inhibition of Listeria monocytogenes Growth by Lactic Acid, Monolaurin, and Nisin▿

    Science.gov (United States)

    Tokarskyy, Oleksandr; Marshall, Douglas L.

    2008-01-01

    The combined lactic acid, monolaurin, and nisin effects on time-to-detection (optical density at 600 nm) extension were greater (P Monolaurin exposure caused C12:0 cell membrane incorporation. Lactic acid caused increased monolaurin C12:0 membrane incorporation, while nisin had no influence. We postulate that lactic acid-enhanced monolaurin C12:0 incorporation into the cell membrane increased membrane fluidity resulting in increased nisin activity. PMID:18820062

  17. Development of a Controlled Release of Salicylic Acid Loaded Stearic Acid-Oleic Acid Nanoparticles in Cream for Topical Delivery

    Directory of Open Access Journals (Sweden)

    J. O. Woo

    2014-01-01

    Full Text Available Lipid nanoparticles are colloidal carrier systems that have extensively been investigated for controlled drug delivery, cosmetic and pharmaceutical applications. In this work, a cost effective stearic acid-oleic acid nanoparticles (SONs with high loading of salicylic acid, was prepared by melt emulsification method combined with ultrasonication technique. The physicochemical properties, thermal analysis and encapsulation efficiency of SONs were studied. TEM micrographs revealed that incorporation of oleic acid induces the formation of elongated spherical particles. This observation is in agreement with particle size analysis which also showed that the mean particle size of SONs varied with the amount of OA in the mixture but with no effect on their zeta potential values. Differential scanning calorimetry analysis showed that the SONs prepared in this method have lower crystallinity as compared to pure stearic acid. Different amount of oleic acid incorporated gave different degree of perturbation to the crystalline matrix of SONs and hence resulted in lower degrees of crystallinity, thereby improving their encapsulation efficiencies. The optimized SON was further incorporated in cream and its in vitro release study showed a gradual release for 24 hours, denoting the incorporation of salicylic acid in solid matrix of SON and prolonging the in vitro release.

  18. [The size of nanoparticles after incorporation into gastroresistant spheroids].

    Science.gov (United States)

    Duvivier; Grandfils, C; Léonard, F; Evrard, B; Delattre, L

    1997-01-01

    Nanoparticles can be used as an attractive carrier for the controlled delivery of drugs by the oral route. This nanoparticular delivery system can protect an active ingredient from enzymatic degradations and enhance its absorption from the intestinal mucosa. We studied the development of a gastroresistant dosage form for the oral administration of nanoparticles. Fast disintegrating pellets were used for the administration of nanoparticles and for their transit to the site of absorption. A gastroresistant film was applied onto the pellets to protect the nanoparticles and/ or the active substance from the acid gastric environment. The integrity of the nanoparticle size was assessed after two critical manufacturing steps: the extrusion/spheronisation process and the coating process. The determination of the nanoparticles size distribution was performed by photon correlation spectroscopy (PCS). The comparison of the PCS results between the original nanoparticles and the nanoparticles incorporated in the pellets shows a very low aggregation. Moreover the coating process was not a critical step since it was not responsible for an additional agglomeration of the nanoparticles. In conclusion, our manufacturing process allows the redispersion of the nanoparticles with a little change of the size distribution. In a next study we well try to quantify the release of the nanoparticles from the pellets.

  19. Chitosan-incorporated different nanocomposite HPMC films for food preservation

    Science.gov (United States)

    Shanmuga Priya, D.; Suriyaprabha, R.; Yuvakkumar, R.; Rajendran, V.

    2014-02-01

    Chitosan nanoparticles were synthesized by cross-linking with sodium tripolyphosphate (TPP) using ionic gelation method and casted into hydroxypropyl methylcellulose (HPMC) films. XRD, FTIR, and UV-Vis spectra showed the corresponding phase, characteristic peaks of CS-TPP functional groups, and transmittance of the films, respectively. Oleic acid, TiO2, neem powder, and Ag of equal ratio were added as an additive to the optimized 1 wt% of chitosan-HPMC films and studied for its mechanical, solubility, thermal, structural, and antimicrobial property. The better physio-chemical and biological properties are achieved in the films incorporated with TiO2 and neem. The characterized films were directly tested for the preservation of grape and plums and for their decay index. Polyphenol oxidase and peroxidase activity of the preserved fruits showed that grape and plums remained unchanged, respectively, for 10 days and for 3 weeks. This study reveals that shelf life of the grape using TiO2- and neem-doped CS-HPMC films was extended up to 10 days with good sensory and textural qualities compared with other films.

  20. Structural Modification in Carbon Nanotubes by Boron Incorporation

    Directory of Open Access Journals (Sweden)

    Handuja Sangeeta

    2009-01-01

    Full Text Available Abstract We have synthesized boron-incorporated carbon nanotubes (CNTs by decomposition of ferrocene and xylene in a thermal chemical vapor deposition set up using boric acid as the boron source. Scanning and transmission electron microscopy studies of the synthesized CNT samples showed that there was deterioration in crystallinity and improvement in alignment of the CNTs as the boron content in precursor solution increased from 0% to 15%. Raman analysis of these samples showed a shift of ~7 cm−1in wave number to higher side and broadening of the G band with increasing boron concentration along with an increase in intensity of the G band. Furthermore, there was an increase in the intensity of the D band along with a decrease in its wave number position with increase in boron content. We speculate that these structural modifications in the morphology and microstructure of CNTs might be due to the charge transfer from boron to the graphite matrix, resulting in shortening of the carbon–carbon bonds.

  1. Incorporating climate change into systematic conservation planning

    Science.gov (United States)

    Groves, Craig R.; Game, Edward T.; Anderson, Mark G.; Cross, Molly; Enquist, Carolyn; Ferdana, Zach; Girvetz, Evan; Gondor, Anne; Hall, Kimberly R.; Higgins, Jonathan; Marshall, Rob; Popper, Ken; Schill, Steve; Shafer, Sarah L.

    2012-01-01

    The principles of systematic conservation planning are now widely used by governments and non-government organizations alike to develop biodiversity conservation plans for countries, states, regions, and ecoregions. Many of the species and ecosystems these plans were designed to conserve are now being affected by climate change, and there is a critical need to incorporate new and complementary approaches into these plans that will aid species and ecosystems in adjusting to potential climate change impacts. We propose five approaches to climate change adaptation that can be integrated into existing or new biodiversity conservation plans: (1) conserving the geophysical stage, (2) protecting climatic refugia, (3) enhancing regional connectivity, (4) sustaining ecosystem process and function, and (5) capitalizing on opportunities emerging in response to climate change. We discuss both key assumptions behind each approach and the trade-offs involved in using the approach for conservation planning. We also summarize additional data beyond those typically used in systematic conservation plans required to implement these approaches. A major strength of these approaches is that they are largely robust to the uncertainty in how climate impacts may manifest in any given region.

  2. Incorporating flow into practice and performance.

    Science.gov (United States)

    Kirchner, Joann Marie

    2011-01-01

    In the music profession, individuals often work under stress filled conditions. This is especially true for individuals making their living as performing musicians. Musical performance anxiety has been well documented in both students and professionals. For some, the experience may lead to a termination of what might otherwise remain a successful performing career. Humans are susceptible to anxiety and so the phenomenon of musical performance anxiety is not likely to disappear. Learning how to effectively deal with musical performance anxiety is paramount for those in the performing arts. Entering a state of flow, in which there is total absorption in an activity, allows for the possiblity of any ensuing anxiety to become facilitative, rather than debilitative. This article will discuss several characteristics of flow, as defined by Mihalyi Csikszentmihalyi, and provide practical applications for musical practice and performance in an attempt to counterbalance musical performance anxiety. Musicians will benefit from a closer examination of the elements of flow and means of incorporating these elements into practice and performance.

  3. Incorporating neurophysiological concepts in mathematical thermoregulation models

    Science.gov (United States)

    Kingma, Boris R. M.; Vosselman, M. J.; Frijns, A. J. H.; van Steenhoven, A. A.; van Marken Lichtenbelt, W. D.

    2014-01-01

    Skin blood flow (SBF) is a key player in human thermoregulation during mild thermal challenges. Various numerical models of SBF regulation exist. However, none explicitly incorporates the neurophysiology of thermal reception. This study tested a new SBF model that is in line with experimental data on thermal reception and the neurophysiological pathways involved in thermoregulatory SBF control. Additionally, a numerical thermoregulation model was used as a platform to test the function of the neurophysiological SBF model for skin temperature simulation. The prediction-error of the SBF-model was quantified by root-mean-squared-residual (RMSR) between simulations and experimental measurement data. Measurement data consisted of SBF (abdomen, forearm, hand), core and skin temperature recordings of young males during three transient thermal challenges (1 development and 2 validation). Additionally, ThermoSEM, a thermoregulation model, was used to simulate body temperatures using the new neurophysiological SBF-model. The RMSR between simulated and measured mean skin temperature was used to validate the model. The neurophysiological model predicted SBF with an accuracy of RMSR temperature. This study shows that (1) thermal reception and neurophysiological pathways involved in thermoregulatory SBF control can be captured in a mathematical model, and (2) human thermoregulation models can be equipped with SBF control functions that are based on neurophysiology without loss of performance. The neurophysiological approach in modelling thermoregulation is favourable over engineering approaches because it is more in line with the underlying physiology.

  4. Incorporating infiltration modelling in urban flood management

    Directory of Open Access Journals (Sweden)

    A. S. Jumadar

    2008-06-01

    Full Text Available Increasing frequency and intensity of flood events in urban areas can be linked to increase in impervious area due to urbanization, exacerbated by climate change. The established approach of conveying storm water by conventional drainage systems has contributed to magnification of runoff volume and peak flows beyond those of undeveloped catchments. Furthermore, the continuous upgrading of such conventional systems is costly and unsustainable in the long term. Sustainable drainage systems aim at addressing the adverse effects associated with conventional systems, by mimicking the natural drainage processes, encouraging infiltration and storage of storm water. In this study we model one of the key components of SuDS, the infiltration basins, in order to assert the benefits of the approach. Infiltration modelling was incorporated in the detention storage unit within the one-dimensional urban storm water management model, EPA-SWMM 5.0. By introduction of infiltration modelling in the storage, the flow attenuation performance of the unit was considerably improved. The study also examines the catchment scale impact of both source and regional control storage/infiltration systems. Based on the findings of two case study areas modelled with the proposed options, it was observed that source control systems have a greater and much more natural impact at a catchment level, with respect to flow attenuation, compared to regional control systems of which capacity is equivalent to the sum of source control capacity at the catchment.

  5. Improved Josephson Qubits incorporating Crystalline Silicon Dielectrics

    Science.gov (United States)

    Gao, Yuanfeng; Maurer, Leon; Hover, David; Patel, Umeshkumar; McDermott, Robert

    2010-03-01

    Josephson junction phase quibts are a leading candidate for scalable quantum computing in the solid state. Their energy relaxation times are currently limited by microwave loss induced by a high density of two-level state (TLS) defects in the amorphous dielectric films of the circuit. It is expected that the integration of crystalline, defect-free dielectrics into the circuits will yield substantial improvements in qubit energy relaxation times. However, the epitaxial growth of a crystalline dielectric on a metal underlayer is a daunting challenge. Here we describe a novel approach in which the crystalline silicon nanomembrane of a Silicon-on-Insulator (SOI) wafer is used to form the junction shunt capacitor. The SOI wafer is thermocompression bonded to the device wafer. The handle and buried oxide layers of the SOI are then etched away, leaving the crystalline silicon layer for subsequent processing. We discuss device fabrication issues and present microwave transport data on lumped-element superconducting resonators incorporating the crystalline silicon.

  6. Incorporation of salinity in Water Availability Modeling

    Science.gov (United States)

    Wurbs, Ralph A.; Lee, Chihun

    2011-10-01

    SummaryNatural salt pollution from geologic formations in the upper watersheds of several large river basins in the Southwestern United States severely constrains the use of otherwise available major water supply sources. The Water Rights Analysis Package modeling system has been routinely applied in Texas since the late 1990s in regional and statewide planning studies and administration of the state's water rights permit system, but without consideration of water quality. The modeling system was recently expanded to incorporate salinity considerations in assessments of river/reservoir system capabilities for supplying water for environmental, municipal, agricultural, and industrial needs. Salinity loads and concentrations are tracked through systems of river reaches and reservoirs to develop concentration frequency statistics that augment flow frequency and water supply reliability metrics at pertinent locations for alternative water management strategies. Flexible generalized capabilities are developed for using limited observed salinity data to model highly variable concentrations imposed upon complex river regulation infrastructure and institutional water allocation/management practices.

  7. Incorporation of proteins into biomimetic hydroxyapatite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.; Groot, K. de [Leiden Univ. (Netherlands). Biomaterials Research Group; IsoTis, Bilthoven (Netherlands); Layrolle, P. [IsoTis, Bilthoven (Netherlands); Blitterswijk, C.A. van [IsoTis, Bilthoven (Netherlands); Twente Univ., Enschede (Netherlands)

    2001-07-01

    Hydroxyapatite coating was biomimetically deposited on titanium alloy (Ti6Al4V). Various concentrations (10 ng/ml - 1 {mu}g/ml) of bovine serum albumin (BSA) were added into a supersaturated calcium phosphate solution (CPS) at physiological temperature and pH of 7.4. Pre-treated Ti6Al4V plates were immersed into such solution for 48 hours at 37 C. BSA was co-precipitated with the crystals during the coating process. A white and thick (30 - 50 {mu}m) coating was uniformly deposited on titanium surfaces. The produced coatings were evaluated and protein release was measured. Results revealed: at higher BSA concentrations in the solution, the coating changed its microstructure; the crystal size of the coating and the coating thickness decreased indicating a crystal growth inhibition. Loading amounts of protein in the coating increased with higher concentration in the solution. Protein was incorporated into whole layer of coating and lead to a slow release. These results indicated that biomimetic hydroxyapatite coatings are suitable carriers for proteins. (orig.)

  8. Incorporating Hypnosis into Pediatric Clinical Encounters.

    Science.gov (United States)

    Pendergrast, Robert A

    2017-03-16

    Increasing numbers of licensed health professionals who care for children have been trained in clinical hypnosis. The evidence base for the safety and efficacy of this therapeutic approach in a wide variety of conditions is also growing. Pediatricians and other health professionals who have received training may wish to apply these skills in appropriate clinical scenarios but still may be unsure of the practical matters of how to incorporate this skill-set into day to day practice. Moreover, the practical application of such skills will take very different forms depending on the practice setting, types of acute or chronic conditions, patient and family preferences, and the developmental stages of the child or teen. This article reviews the application of pediatric clinical hypnosis skills by describing the use of hypnotic language outside of formal trance induction, by describing natural trance states that occur in children and teens in healthcare settings, and by describing the process of planning a clinical hypnosis encounter. It is assumed that this article does not constitute training in hypnosis or qualify its readers for the application of such skills; rather, it may serve as a practical guide for those professionals who have been so trained, and may serve to inform other professionals what to expect when referring a patient for hypnotherapy. The reader is referred to specific training opportunities and organizations.

  9. Incorporating Hypnosis into Pediatric Clinical Encounters

    Directory of Open Access Journals (Sweden)

    Robert A. Pendergrast

    2017-03-01

    Full Text Available Increasing numbers of licensed health professionals who care for children have been trained in clinical hypnosis. The evidence base for the safety and efficacy of this therapeutic approach in a wide variety of conditions is also growing. Pediatricians and other health professionals who have received training may wish to apply these skills in appropriate clinical scenarios but still may be unsure of the practical matters of how to incorporate this skill-set into day to day practice. Moreover, the practical application of such skills will take very different forms depending on the practice setting, types of acute or chronic conditions, patient and family preferences, and the developmental stages of the child or teen. This article reviews the application of pediatric clinical hypnosis skills by describing the use of hypnotic language outside of formal trance induction, by describing natural trance states that occur in children and teens in healthcare settings, and by describing the process of planning a clinical hypnosis encounter. It is assumed that this article does not constitute training in hypnosis or qualify its readers for the application of such skills; rather, it may serve as a practical guide for those professionals who have been so trained, and may serve to inform other professionals what to expect when referring a patient for hypnotherapy. The reader is referred to specific training opportunities and organizations.

  10. Evolutionary Snowdrift Game Incorporating Costly Punishment

    Directory of Open Access Journals (Sweden)

    Yap Yee Jiun

    2012-01-01

    Full Text Available The role of punishments in promoting cooperation is an important issue. We incorporate costly punishments into the snowdrift game (SG by introducing a third punishing (P character and study the effects.  The punishers, who carry basically a cooperative (C character, are willing to pay a cost of a so as to punish a non-cooperative (D opponent by ß. Depending on the initial fractions of the characters, a, ß, and the cost-to-benefit ratio r in SG, the three-character system evolves either into a steady state consisting only of C and P characters or only of C and D characters in a well-mixed population.  The former situation represents an enhancement in cooperation relative to SG, while the latter is similar to SG. The dynamics in approaching these different steady states are found to be different.  Analytically, the key features in the steady states and dynamics obtained by simulations are captured by a set of differential equations.  The sensitivity to the initial distribution of characters is studied by depicting the flow in a phase portrait and analyzing the nature of fixed points. The analysis also shows the role of P-character in preventing a system from invasion by D-character agents. Starting from a population consisting only of C and P agents, a D-character agent intended to invade the system cannot survive when the initial fraction of P-agents is greater than r/ß. Our model, defined intentionally as a simulation algorithm, can be readily generalized to incorporate many interesting effects, such as those in a networked population. ABSTRAK: Peranan hukuman dalam meningkatkan kerjasama merupakan isu penting.  Hukuman berat diterapkan ke dalam permainan hanyutan salji (snowdrift game (SG dengan memperkenalkan karekter penghukum (P ketiga dan akibatnya dipantau. Penghukum, pada asasnya membawa watak koperatif (C, sanggup membayar kos a, agar dia menghukum lawan yang tidak koperatif (D dengan ß. Bergantung kepada pecahan permulaan watak

  11. Coral barium incorporation: implications for proxy applications

    Science.gov (United States)

    Gonneea, M. E.; Cohen, A. L.; Charette, M. A.

    2012-12-01

    Coral Ba/Ca ratios have been proposed as proxies for various environmental variables including sediment loading, upwelling and groundwater input. Two assumptions that underpin the application of Ba/Ca ratios as an environmental proxy is 2) that corals take up Ba/Ca in concentrations proportional to seawater concentrations and 1) that the specified forcing mechanism influences seawater [Ba]. Here we present data from laboratory experiments that demonstrates corals reared in a range of seawater [Ba] linearly incorporate this signature in their skeletal Ba/Ca ratios. Observed coral Ba/Ca perturbations above baseline typically range from 5-15 μmol/mol which is ~100-500% increase over baseline. Other factors known to influence coral Ba/Ca include the temperature dependence on the partition coefficient and mass fraction aragonite precipitated by the coral which may be linked to calcification rate. In our experiments, calcification rate increased with temperature, thus the observed coral partition coefficient is the net effect of temperature (Ba/Ca increase at lower temperature) and calcification rate (Ba/Ca increase at higher temperature). We observed that the partition coefficient for reared coral Ba/Ca increased 20% 27.7 to 22.5 C, much less than observed Ba/Ca perturbations. Thus we predict that seawater [Ba] drives coral Ba/Ca signals in many locations. We present a model framework to calculate the expected contribution from sediment input, upwelling and groundwater discharge that is needed to produce this signature in corals growing in receiving waters. Finally we apply this model to a coral record from the Yucatan Peninsula, Mexico, recording groundwater discharge to the coastal ocean.

  12. Incorporating psychological influences in probabilistic cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kujawski, Edouard; Alvaro, Mariana; Edwards, William

    2004-01-08

    Today's typical probabilistic cost analysis assumes an ''ideal'' project that is devoid of the human and organizational considerations that heavily influence the success and cost of real-world projects. In the real world ''Money Allocated Is Money Spent'' (MAIMS principle); cost underruns are rarely available to protect against cost overruns while task overruns are passed on to the total project cost. Realistic cost estimates therefore require a modified probabilistic cost analysis that simultaneously models the cost management strategy including budget allocation. Psychological influences such as overconfidence in assessing uncertainties and dependencies among cost elements and risks are other important considerations that are generally not addressed. It should then be no surprise that actual project costs often exceed the initial estimates and are delivered late and/or with a reduced scope. This paper presents a practical probabilistic cost analysis model that incorporates recent findings in human behavior and judgment under uncertainty, dependencies among cost elements, the MAIMS principle, and project management practices. Uncertain cost elements are elicited from experts using the direct fractile assessment method and fitted with three-parameter Weibull distributions. The full correlation matrix is specified in terms of two parameters that characterize correlations among cost elements in the same and in different subsystems. The analysis is readily implemented using standard Monte Carlo simulation tools such as {at}Risk and Crystal Ball{reg_sign}. The analysis of a representative design and engineering project substantiates that today's typical probabilistic cost analysis is likely to severely underestimate project cost for probability of success values of importance to contractors and procuring activities. The proposed approach provides a framework for developing a viable cost management strategy for

  13. Solutions to Overland Flow Incorporating Infiltration

    Science.gov (United States)

    Boyraz, Uǧur; Gülbaz, Sezar; Melek Kazezyılmaz-Alhan, Cevza

    2017-04-01

    Overland flow is represented by flood wave propagation and plays an important role in hydrology and hydraulics. Flood wave propagation concerns many disciplines and thus, scientists such as hydrologists, city planners, irrigation practitioners and hydraulic and environmental engineers are studying on developing accurate solutions for flood wave equations. The dynamic wave equations consist of continuity and momentum equations and describe unsteady and non-uniform flow conditions. Diffusion wave equations can be derived from the dynamic wave equations by neglecting the local and convective acceleration terms in the momentum equation. The kinematic wave model obtained by ignoring both inertial and pressure terms is the simplest routing method which substitutes a steady uniform flow relationship in the momentum equation. In order to calculate the overland flow, these three types of flood wave equations are solved with many different numerical techniques. Nevertheless, the dynamic interaction between surface flow and infiltration is not sufficiently investigated. In this study, the effect of infiltration on overland flow is explored by incorporating the integrated Horton equation into the flood wave equations. Integrated Horton method calculates infiltration under variable rainfall intensity. MacCormack explicit finite difference method is employed in solving the coupled infiltration-overland flow problem. Hydrographs for overland flow with and without