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Sample records for coated targets utilizing

  1. Ceramic thermal barrier coatings for electric utility gas turbine engines

    NASA Technical Reports Server (NTRS)

    Miller, R. A.

    1986-01-01

    Research and development into thermal barrier coatings for electric utility gas turbine engines is reviewed critically. The type of coating systems developed for aircraft applications are found to be preferred for clear fuel electric utility applications. These coating systems consists of a layer of plasma sprayed zirconia-yttria ceramic over a layer of MCrAly bond coat. They are not recommended for use when molten salts are presented. Efforts to understand coating degradation in dirty environments and to develop corrosion resistant thermal barrier coatings are discussed.

  2. Metallic and nonmetallic coatings for ICF targets

    SciTech Connect

    Hendricks, C.D.; Crane, J.K.; Hsieh, E.J.; Meyer, S.F.

    1981-04-17

    Some fusion targets designed to be driven by 0.35 to 1 ..mu..m laser light are glass spheres coated with layers of various materials such as hydrocarbons, fluorocarbons, beryllium, copper, gold, platinum, etc. The glass shell, which is filled with gas, liquid or solid deuterium-tritium fuel, must have remarkably good surface and wall thickness uniformity. Methods for depositing the various materials will be discussed. They include plasma polymerization, electro-deposition, sputtering and evaporation. Many of the difficulties encountered in the coating processes are the result of coating on free spheres with very small radii - 35 to 500 micrometers. Several means of overcoming the problems will be described and experimental results presented.

  3. Novel Corrosion Control Coating Utilizing Carbon Nanotechnology

    DTIC Science & Technology

    2009-02-01

    Hawkins Tesla NanoCoatings Limited Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is...Phone: 217-373-6767 E-mail: susan.a.drozdz@us.army.mil Todd Hawkins Tesla NanoCoatings Limited P.O. Box 270 Massillon, Ohio 44646 Phone: 330-880-5229 E-mail: todd@teslanano.com TESLAN™

  4. Thermal-barrier coatings for utility gas turbines

    NASA Technical Reports Server (NTRS)

    Levine, S. R.; Miller, R. A.

    1982-01-01

    The potential of thermal barrier coatings for use in utility gas turbines was assessed. Pressurized passage and ambient pressure doped fuel burner rig tests revealed that thermal barrier coatings are not resistant to dirty combustion environments. However, present thermal barrier coatings, such as duplex partially stabilized zirconia and duplex Ca2SiO4 have ample resistance to the thermo-mechanical stress and temperature levels anticipated for heavy duty gas turbines firing clean fuel as revealed by clean fuel pressurized passage and ambient pressure burner rig tests. Thus, it is appropriate to evaluate such coatings on blades, vanes and combustors in the field. However, such field tests should be backed up with adequate effort in the areas of coating application technology and design analysis so that the field tests yield unequivocal results.

  5. FOYER SHOWING THE UTILITY AND COAT CLOSETS. VIEW FACING NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FOYER SHOWING THE UTILITY AND COAT CLOSETS. VIEW FACING NORTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, U-Shaped Three-Bedroom Duplex Type 4, Acacia Road, Birch Circle, Cedar Drive and Elm Drive, Pearl City, Honolulu County, HI

  6. Matrix Pre-Coated Targets for Direct Lipid Analysis and Imaging of Tissue

    PubMed Central

    Yang, Junhai; Caprioli, Richard M.

    2013-01-01

    We have developed targets pre-coated with matrix for imaging lipids in tissues using MALDI-MS. Thin tissue sections (rat kidney and mouse or rat brains) were placed onto 2,5-diaminonaphthalene pre-coated targets (prepared beforehand by a protocol utilizing sublimation) and were washed with ammonium formate solution. After a brief drying period, the target slides were imaged by MALDI MS. The resulting images from these sections were of equivalent quality to those obtained using the usual post-coating approach such as sublimation and spraying in term of the sharpness of substructures in the images demonstrated by imaging at spatial resolutions of 100, 10 and 5 μm. Matrix pre-coated targets have a shelf-life more than 6 months when kept in a dark, non-humid environment such as a non-transparent desiccator. PMID:23418860

  7. Polyvinyl alcohol coating of polystyrene inertial confinement fusion targets

    NASA Technical Reports Server (NTRS)

    Annamalai, P.; Lee, M. C.; Crawley, R. L.; Downs, R. L.

    1985-01-01

    An inertial confinement fusion (ICF) target made of polystyrene is first levitated in an acoustic field. The surface of the target is then etched using an appropriate solution (e.g., cyclohexane) to enhance the wetting characteristics. A specially prepared polyvinyl alcohol solution is atomized using an acoustic atomizer and deposited on the surface of the target. The solution is air dried to form a thin coating (2 microns) on the target (outside diameter of about 350-850 microns). Thicker coatings are obtained by repeated applications of the coating solutions. Preliminary results indicate that uniform coatings may be achievable on the targets with a background surface smoothness in the order of 1000 A.

  8. Magnetron co-sputtering system for coating ICF targets

    SciTech Connect

    Hsieh, E.J.; Meyer, S.F.; Halsey, W.G.; Jameson, G.T.; Wittmayer, F.J.

    1981-12-09

    Fabrication of Inertial Confinement Fusion (ICF) targets requires deposition of various types of coatings on microspheres. The mechanical strength, and surface finish of the coatings are of concern in ICF experiments. The tensile strength of coatings can be controlled through grain refinement, selective doping and alloy formation. We have constructed a magnetron co-sputtering system to produce variable density profile coatings with high tensile strength on microspheres. The preliminary data on the properties of a Au-Cu binary alloy system by SEM and STEM analysis is presented.

  9. Preparation of germanium doped plasma polymerized coatings as ICF target ablators

    SciTech Connect

    Brusasco, R M; Saculla, M D; Cook, R C

    1994-10-05

    Targets for Inertial Confinement Fusion (ICF) experiments at the Lawrence Livermore National Laboratory (LLNL) utilize an organic (CH) ablator coating prepared by plasma polymerization. Some of these experiments require a mid-Z dopant in the ablator coating to modify the opacity of the shell. Bromine had been used in the past, but the surface finish of brominated CH degrades rapidly with time upon exposure to air. This paper describes the preparation and characterization of plasma polymer layers containing germanium as a dopant at concentrations of between 1.25 and 2.25 atom percent. The coatings are stable in air and have an rms surface roughness of 7--9 nm (modes 10--1,000) which is similar to that obtained with undoped coatings. High levels of dopant result in cracking of the inner mandrel during target assembly. Possible explanations for the observed cracking behavior will be discussed.

  10. Ultrasmooth plasma polymerized coatings for laser-fusion targets

    SciTech Connect

    Letts, S.A.; Myers, D.W.; Witt, L.A.

    1980-08-26

    Coatings for laser fusion targets were deposited up to 135 ..mu..m thick by plasma polymerization onto 140 ..mu..m diameter DT filled glass microspheres. Ultrasmooth surfaces (no defect higher than 0.1 ..mu..m) were achieved by eliminating particulate contamination. Process generated particles were eliminated by determining the optimum operating conditions of power, gas flow, and pressure, and maintaining these conditions through feedback control. From a study of coating defects grown over known surface irregularities, a quantitative relationship between irregularity size, film thickness, and defect size was determined. This relationship was used to set standards for the maximum microshell surface irregularity tolerable in the production of hydrocarbon or fluorocarbon coated laser fusion targets.

  11. In vitro evaluation of coating polymers for enteric coating and human ileal targeting.

    PubMed

    Huyghebaert, Nathalie; Vermeire, An; Remon, Jean Paul

    2005-07-14

    Recombinant interleukin-10 producing Lactococcus lactis is an alternative therapy for Crohn's disease. For in vivo interleukin-10 production, thymidine, the essential feed component of these recombinant bacteria should be coadministered. Different coating polymers were evaluated in vitro for enteric properties and targeting suitability to the ileum, the major site of inflammation in Crohn's disease. To guarantee ileal delivery, the polymer must dissolve from pH 6.8 and allow complete release within 40 min. Aqoat AS-HF coated pellets (15%) showed poor enteric properties and thymidine was released below pH 6.8. Eudragit FS30D coated pellets (15%) showed good enteric properties, but no thymidine was released within 40 min at pH 6.8. Eudragit S coated pellets (15%) showed good enteric properties after curing at elevated temperature while no thymidine was released within 40 min at pH 6.8. In another approach to pass the proximal small intestine intact, pellets were coated with 30% Eudragit L30D-55. At pH 6.0, they showed a lag-phase of 20 min. No influence of layer thickness was seen above pH 6.5. Alternatively, pellets were coated with a mixture of Eudragit FS30D/L30D-55 but they showed poor enteric properties and thymidine was released below pH 6.8. In conclusion, none of the tested polymers/mixtures ensured enteric properties and ileal targeting.

  12. Advanced ceramic coating development for industrial/utility gas turbines

    NASA Technical Reports Server (NTRS)

    Vogan, J. W.; Stetson, A. R.

    1982-01-01

    A program was conducted with the objective of developing advanced thermal barrier coating (TBC) systems. Coating application was by plasma spray. Duplex, triplex and graded coatings were tested. Coating systems incorporated both NiCrAly and CoCrAly bond coats. Four ceramic overlays were tested: ZrO2.82O3; CaO.TiO2; 2CaO.SiO2; and MgO.Al2O3. The best overall results were obtained with a CaO.TiO2 coating applied to a NiCrAly bond coat. This coating was less sensitive than the ZrO2.8Y2O3 coating to process variables and part geometry. Testing with fuels contaminated with compounds containing sulfur, phosphorus and alkali metals showed the zirconia coatings were destabilized. The calcium titanate coatings were not affected by these contaminants. However, when fuels were used containing 50 ppm of vanadium and 150 ppm of magnesium, heavy deposits were formed on the test specimens and combustor components that required frequent cleaning of the test rig. During the program Mars engine first-stage turbine blades were coated and installed for an engine cyclic endurance run with the zirconia, calcium titanate, and calcium silicate coatings. Heavy spalling developed with the calcium silicate system. The zirconia and calcium titanate systems survived the full test duration. It was concluded that these two TBC's showed potential for application in gas turbines.

  13. Neutron Production from In-situ Heavy Ice Coated Targets at Vulcan

    NASA Astrophysics Data System (ADS)

    Morrison, John; Krygier, A. G.; Kar, S.; Ahmed, H.; Alejo, A.; Clarke, R.; Fuchs, J.; Green, A.; Jung, D.; Kleinschmidt, A.; Najmudin, Z.; Nakamura, H.; Norreys, P.; Notley, M.; Oliver, M.; Roth, M.; Vassura, L.; Zepf, M.; Borghesi, M.; Freeman, R. R.

    2015-05-01

    Laser based neutron production experiments have been performed utilizing ultra-high intensity laser accelerated ions impinging upon a secondary target. The neutron yield from such experiments may be improved if the accelerated ions were primarily deuterons taking advantage of the d-d cross section. Recent experiments have demonstrated that selective deuteron acceleration from in-situ heavy ice coating of targets can produce ion spectra where deuterons comprise > 99 % of the measured ions. Results will be presented from integrated neutron production experiments from heavy ice targets coated in-situ recently performed on the Vulcan laser at Rutherford Appleton Laboratory. We are grateful for the Staff at RAL and acknowledge funding from the US DoE. AFOSR, European Social Fund, and the Czech Republic.

  14. Transient waveform recording utilizing TARGET7 ASIC

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Liu, S.; Wang, Y.; Yang, C.; Zhu, X.; Feng, C.; An, Q.

    2017-04-01

    TARGET7, the 7th-generation TeV Array Readout with GSPS (Gigabit Samples Per Second) sampling and Experimental Trigger ASIC, has been initially designed to monolithically and inexpensively instrument large deployments of semiconductor photon detectors for large neutrino and muon detectors. It is a switched capacitor array (SCA) based transient waveform recorder with 3-dB bandwidth of 500 MHz; a large dynamic range of 1.8 V; high sampling rate (typically 1 GSPS); high channel density (16 channels per ASIC); low power consumption (0<1 mW/channel) and deep analog storage buffer (16,384 samples per channel). Moreover, each channel has an integrated Wilkinson ADC (Analog-to-Digital Convertor) for digitization. In this paper, a test board with the chip is described. Calibration methods, timing performance as well as its application possibility in charge measurement with a comparison to an oscilloscope are studied.

  15. Functional silver coated colloidosomes as targeted carriers for small molecules.

    PubMed

    Sun, Qian; Du, Yao; Zhao, Ziyan; Hall, Elizabeth Anne Howlett; Gao, Hui; Sukhorukov, Gleb B; Routh, Alexander Francis

    2017-03-30

    Colloidosomes have attracted great interest in recent years because of their capability for storage and delivery of small molecules for medical and pharmaceutical applications. However, traditional polymer shell colloidosomes leak low molecular weight drugs due to their intrinsic shell permeability. Here, we report aqueous core colloidosomes with a silver shell, which seals the core and makes the shell impermeable. The silver coated colloidosomes were prepared by reacting L-Ascorbic acid in the microcapsule core with silver nitrate in the wash solution. The silver shell colloidosomes were then modified by using 4,4'-dithiodibutyric acid and linked with rabbit Immunoglobulin G (IgG). Label-free Surface Plasmon Resonance was used to test the specific targeting of the functional silver shell with rabbit antigen. To break the shells, ultrasound treatment was used. The results demonstrate that a new type of functional silver coated colloidosome with immunoassay targeting, non-permeability, and ultrasound sensitivity could be applied to many medical applications.

  16. Targeting breast cancer with sugar-coated carbon nanotubes

    PubMed Central

    Fahrenholtz, Cale D; Hadimani, Mallinath; King, S Bruce; Torti, Suzy V; Singh, Ravi

    2015-01-01

    Aims To evaluate the use of glucosamine functionalized multiwalled carbon nanotubes (glyco-MWCNTs) for breast cancer targeting. Materials & methods Two types of glucosamine functionalized MWCNTs were developed (covalently linked glucosamine and non-covalently phospholipid-glucosamine coated) and evaluated for their potential to bind and target breast cancer cells in vitro and in vivo. Results & conclusion Binding of glyco-MWCNTs in breast cancer cells is mediated by specific interaction with glucose transporters. Glyco-MWCNTs prepared by non-covalent coating with phospholipid-glucosamine displayed an extended blood circulation time, delayed urinary clearance, low tissue retention and increased breast cancer tumor accumulation in vivo. These studies lay the foundation for development of a cancer diagnostic agent based upon glyco-MWCNTs with the potential for superior accuracy over current radiopharmaceuticals. PMID:26296098

  17. Targeting breast cancer with sugar-coated carbon nanotubes.

    PubMed

    Fahrenholtz, Cale D; Hadimani, Mallinath; King, S Bruce; Torti, Suzy V; Singh, Ravi

    2015-01-01

    To evaluate the use of glucosamine functionalized multiwalled carbon nanotubes (glyco-MWCNTs) for breast cancer targeting. Two types of glucosamine functionalized MWCNTs were developed (covalently linked glucosamine and non-covalently phospholipid-glucosamine coated) and evaluated for their potential to bind and target breast cancer cells in vitro and in vivo. Binding of glyco-MWCNTs in breast cancer cells is mediated by specific interaction with glucose transporters. Glyco-MWCNTs prepared by non-covalent coating with phospholipid-glucosamine displayed an extended blood circulation time, delayed urinary clearance, low tissue retention and increased breast cancer tumor accumulation in vivo. These studies lay the foundation for development of a cancer diagnostic agent based upon glyco-MWCNTs with the potential for superior accuracy over current radiopharmaceuticals.

  18. Targeting multiple types of tumors using NKG2D-coated iron oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Wu, Ming-Ru; Cook, W. James; Zhang, Tong; Sentman, Charles L.

    2014-11-01

    Iron oxide nanoparticles (IONPs) hold great potential for cancer therapy. Actively targeting IONPs to tumor cells can further increase therapeutic efficacy and decrease off-target side effects. To target tumor cells, a natural killer (NK) cell activating receptor, NKG2D, was utilized to develop pan-tumor targeting IONPs. NKG2D ligands are expressed on many tumor types and its ligands are not found on most normal tissues under steady state conditions. The data showed that mouse and human fragment crystallizable (Fc)-fusion NKG2D (Fc-NKG2D) coated IONPs (NKG2D/NPs) can target multiple NKG2D ligand positive tumor types in vitro in a dose dependent manner by magnetic cell sorting. Tumor targeting effect was robust even under a very low tumor cell to normal cell ratio and targeting efficiency correlated with NKG2D ligand expression level on tumor cells. Furthermore, the magnetic separation platform utilized to test NKG2D/NP specificity has the potential to be developed into high throughput screening strategies to identify ideal fusion proteins or antibodies for targeting IONPs. In conclusion, NKG2D/NPs can be used to target multiple tumor types and magnetic separation platform can facilitate the proof-of-concept phase of tumor targeting IONP development.

  19. Liposome-coated quantum dots targeting the sentinel lymph node

    NASA Astrophysics Data System (ADS)

    Chu, Maoquan; Zhuo, Shu; Xu, Jiang; Sheng, Qiunan; Hou, Shengke; Wang, Ruifei

    2010-01-01

    Sentinel lymph node (SLN) mapping with near-infrared (NIR) quantum dot (QDs) have many advantages over traditional methods. However, as an inorganic nanomaterial, QDs have low biocompatibility and low affinity to the lymphatic system. Here, we encapsulated QDs into nanoscale liposomes and then used these liposome-coated QDs for SLN mapping. The results showed that the liposome-coated QDs exhibited core-shell characterization, and their fluorescence emission did not decrease but slightly increased after being continuously excited by a xenon lamp source (150 W) at 488 nm at 37 °C for 1 h. After storing at 4 °C for more than one and half years, the liposome-coated QDs were found to have retained their spherical structure containing a large amount of QDs. When liposome-coated QDs with average size of 55.43 nm were injected intradermally into the paw of a mouse, the SLN was strongly fluorescent within only a few seconds and visualized easily in real time. Moreover, the fluorescence of the QDs trapped in the SLN could be observed for at least 24 h. Compared with the SLN mapping of QDs absent of liposomes and liposome-coated QDs with a larger average size (100.3 and 153.6 nm), more QDs migrated into the SLN when the liposome-coated QDs with smaller average size (55.43 nm) were injected. This technique may make a great contribution to the improvement of the biocompatibility of QDs and the targeting delivery capacity of QDs into the SLN.

  20. Superparamagnetic Iron Oxide Nanoparticles Coated with Galactose-Carrying Polymer for Hepatocyte Targeting

    PubMed Central

    Yoo, Mi Kyong; Kim, In Yong; Kim, Eun Mi; Jeong, Hwan-Jeong; Lee, Chang-Moon; Jeong, Yong Yeon; Akaike, Toshihiro; Cho, Chong Su

    2007-01-01

    Our goal is to develop the functionalized superparamagnetic iron oxide nanoparticles (SPIONs) demonstrating the capacities to be delivered in liver specifically and to be dispersed in physiological environment stably. For this purpose, SPIONs were coated with polyvinylbenzyl-O-β-D-galactopyranosyl-D-gluconamide (PVLA) having galactose moieties to be recognized by asialoglycoprotein receptors (ASGP-R) on hepatocytes. For use as a control, we also prepared SPIONs coordinated with 2-pyrrolidone. The sizes, size distribution, structure, and coating of the nanoparticles were characterized by transmission electron microscopy (TEM), electrophoretic light scattering spectrophotometer (ELS), X-ray diffractometer (XRD), and Fourier transform infrared (FT-IR), respectively. Intracellular uptake of the PVLA-coated SPIONs was visualized by confocal laser scanning microscopy, and their hepatocyte-specific delivery was also investigated through magnetic resonance (MR) images of rat liver. MRI experimental results indicated that the PVLA-coated SPIONs possess the more specific accumulation property in liver compared with control, which suggests their potential utility as liver-targeting MRI contrast agent. PMID:18317519

  1. Characterization of Niobium Oxide Films Deposited by High Target Utilization Sputter Sources

    SciTech Connect

    Chow, R; Ellis, A D; Loomis, G E; Rana, S I

    2007-01-29

    High quality, refractory metal, oxide coatings are required in a variety of applications such as laser optics, micro-electronic insulating layers, nano-device structures, electro-optic multilayers, sensors and corrosion barriers. A common oxide deposition technique is reactive sputtering because the kinetic mechanism vaporizes almost any solid material in vacuum. Also, the sputtered molecules have higher energies than those generated from thermal evaporation, and so the condensates are smoother and denser than those from thermally-evaporated films. In the typical sputtering system, target erosion is a factor that drives machine availability. In some situations such as nano-layered capacitors, where the device's performance characteristics depends on thick layers, target life becomes a limiting factor on the maximizing device functionality. The keen interest to increase target utilization in sputtering has been addressed in a variety of ways such as target geometry, rotating magnets, and/or shaped magnet arrays. Also, a recent sputtering system has been developed that generates a high density plasma, directs the plasma beam towards the target in a uniform fashion, and erodes the target in a uniform fashion. The purpose of this paper is to characterize and compare niobia films deposited by two types of high target utilization sputtering sources, a rotating magnetron and a high density plasma source. The oxide of interest in this study is niobia because of its high refractive index. The quality of the niobia films were characterized spectroscopically in optical transmission, ellipsometrically, and chemical stoichiometry with X-ray photo-electron spectroscopy. The refractive index, extinction coefficients, Cauchy constants were derived from the ellipsometric modeling. The mechanical properties of coating density and stress are also determined.

  2. Targeting signals and subunit interactions in coated vesicle adaptor complexes

    PubMed Central

    1995-01-01

    There are two clathrin-coated vesicle adaptor complexes in the cell, one associated with the plasma membrane and one associated with the TGN. The subunit composition of the plasma membrane adaptor complex is alpha-adaptin, beta-adaptin, AP50, and AP17; while that of the TGN adaptor complex is gamma-adaptin, beta'-adaptin, AP47, and AP19. To search for adaptor targeting signals, we have constructed chimeras between alpha-adaptin and gamma-adaptin within their NH2-terminal domains. We have identified stretches of sequence in the two proteins between amino acids approximately 130 and 330-350 that are essential for targeting. Immunoprecipitation reveals that this region determines whether a construct coassemblies with AP50 and AP17, or with AP47 and AP19. These observations suggest that these other subunits may play an important role in targeting. In contrast, beta- and beta'-adaptins are clearly not involved in this event. Chimeras between the alpha- and gamma-adaptin COOH-terminal domains reveal the presence of a second targeting signal. We have further investigated the interactions between the adaptor subunits using the yeast two-hybrid system. Interactions can be detected between the beta/beta'-adaptins and the alpha/gamma- adaptins, between the beta/beta'-adaptins and the AP50/AP47 subunits, between alpha-adaptin and AP17, and between gamma-adaptin and AP19. These results indicate that the adaptor subunits act in concert to target the complex to the appropriate membrane. PMID:7593184

  3. Targeting Vascular Amyloid in Arterioles of Alzheimer Disease Transgenic Mice with Amyloid Beta Protein Antibody-Coated Nanoparticles

    PubMed Central

    Poduslo, Joseph F.; Hultman, Kristi L.; Curran, Geoffry L.; Preboske, Gregory M.; Chamberlain, Ryan; Marjańska, Małgorzata; Garwood, Michael; Jack, Clifford R.; Wengenack, Thomas M.

    2015-01-01

    The relevance of cerebral amyloid angiopathy (CAA) to the pathogenesis of Alzheimer disease (AD) and dementia in general emphasizes the importance of developing novel targeting approaches for detecting and treating cerebrovascular amyloid (CVA) deposits. We developed a nanoparticle-based technology that utilizes a monoclonal antibody against fibrillar human amyloid-β42 that is surface-coated onto a functionalized phospholipid monolayer. We demonstrate that this conjugated nanoparticle binds to CVA deposits in arterioles of AD transgenic mice (Tg2576) following infusion into the external carotid artery using 3 different approaches. The first 2 approaches utilize a blood vessel enrichment of homogenized brain and a leptomeningeal vessel preparation from thin tangential brain slices from the surface of the cerebral cortex. Targeting of CVA by the antibody-coated nanoparticle was visualized using fluorescent lissamine rhodamine-labeled phospholipids in the nanoparticles, which were compared with fluorescent staining of the endothelial cells and amyloid deposits utilizing confocal laser scanning microscopy. The third approach utilized high field strength magnetic resonance imaging of antibody-coated iron oxide nanoparticles (MIONs) following infusion into the external carotid artery. Dark foci of contrast enhancement in cortical arterioles were observed in T2*-weighted images of ex vivo AD mouse brains that correlated histologically with CVA deposits. The targeting ability of these nanoparticles to CVA provides opportunities for the prevention and treatment of CAA. PMID:21760540

  4. Microbial Penetration and Utilization of Organic Aircraft Fuel-Tank Coatings1

    PubMed Central

    Crum, M. G.; Reynolds, R. J.; Hedrick, H. G.

    1967-01-01

    Microorganisms have been found as contaminants in various types of aircraft fuel tanks. Their presence introduces problems in the operation of the aircraft, including destruction of components such as the organic coatings used as protective linings in the fuel tanks. Microbial penetration and utilization of the currently used organic coatings, EC 776, DV 1180, PR 1560, and DeSoto 1080, were determined by changes in electrical resistances of the coatings; mycelial weight changes; growth counts of the bacteria; and manometric determinations on Pseudomonas aeruginosa (GD-FW B-25) and Cladosporium resinae (QMC-7998). The results indicate EC 776 and DV 1180 to be less resistant to microbial degradation than the other coatings. Organic coatings, serving as a source of nutrition, would be conducive to population buildups in aircraft fuel tanks. Images Fig. 1 PMID:16349744

  5. Mesoporous Silica Coated Polydopamine Functionalized Reduced Graphene Oxide for Synergistic Targeted Chemo-Photothermal Therapy.

    PubMed

    Shao, Leihou; Zhang, Ruirui; Lu, Jianqing; Zhao, Caiyan; Deng, Xiongwei; Wu, Yan

    2017-01-18

    The integration of different therapies into a single nanoplatform has shown great promise for synergistic tumor treatment. Herein, mesoporous silica (MS) coated polydopamine functionalized reduced graphene oxide (pRGO) further modified with hyaluronic acid (HA) (pRGO@MS-HA) has been utilized as a versatile nanoplatform for synergistic targeted chemo-photothermal therapy against cancer. A facile and green chemical method is adopted for the simultaneous reduction and noncovalent functionalization of graphene oxide (GO) by using mussel inspired dopamine (DA) to enhance biocompatibility and the photothermal effect. Then, it was coated with mesoporous silica (MS) (pRGO@MS) to enhance doxorubicin (DOX) loading and be further modified with the targeting moieties hyaluronic acid (HA). The pH-dependent and near-infrared (NIR) laser irradiation-triggered DOX release from pRGO@MS(DOX)-HA is observed, which could enhance the chemo-photothermal therapy effect. In vitro experimental results confirm that pRGO@MS(DOX)-HA exhibits good dispersibility, excellent photothermal property, remarkable tumor cell killing efficiency, and specificity to target tumor cells. In vivo antitumor experiments further demonstrated that pRGO@MS(DOX)-HA could exhibit an excellent synergistic antitumor efficacy, which is much more distinct than any monotherapy. This work presents a novel nanoplatform which could load chemotherapy drugs with high efficiency and be used as light-mediated photothermal cancer therapy agent.

  6. Glass window coatings for sunlight heat reflection and co-utilization.

    PubMed

    Horowitz, Flavio; Pereira, Marcelo B; de Azambuja, Giovani B

    2011-03-20

    Buildings that simultaneously provide natural illumination and thermal comfort for all seasons have met with increasing demand as conventional resource limitations are realized. In this context, organic and metal-dielectric coatings are tested, and a simple, coated double-glazed window with solar blinds is conceived that includes passive infrared (IR) reflection, active illumination control, and integration to the building envelope. As a result, a proper spectrally selective coating is applied to produce a low-emissivity solar window with climate-adaptive co-utilization of the reflected IR.

  7. Effect of powder and target properties on wrap around effect during coating.

    PubMed

    Sumonsiri, Nutsuda; Barringer, Sheryl A

    2010-10-01

    Tapioca starch, NaCl (28, 135, and 378 μm), corn starch, cocoa powder, soy protein isolate, cheese powder, wheat protein, modified starch, nacho cheese, and sugar were coated at 0 kV for nonelectrostatic and at 25 kV for electrostatic coating onto metal, wood, unoiled paper, oiled paper, unoiled plastic, oiled plastic, fresh bread, and dry bread. Powders and targets were allowed to naturally tribocharge, or all charge was removed before coating. Powder particle size, flowability, resistivity, and target resistivity were reported. Electrostatic coating produced the same or better wrap around, or percent side coverage as nonelectrostatic coating for every powder and target. The greatest electrostatic improvement was found when using powders that had the worst nonelectrostatic side coverage: large particle size (>135 μm), low resistivity, and low cohesiveness, especially on targets that had high-surface resistivity (2 × 10(5) Ωm). Tribocharging had a similar effect as electrostatic coating. In both nonelectrostatic and electrostatic coating, percent side coverage increased as powder particle size decreased, cohesiveness increased, or target resistivity decreased. In electrostatic coating, percent side coverage increased as powder resistivity increased; however, in nonelectrostatic coating, as powder resistivity increased, percent side coverage increased on only oiled plastic and dry bread. Practical Application: The evenness of powder coating on food is very important for consumer acceptability, since consumers judge food from its appearance before they have a chance to taste it. If thick food targets, such as cakes, donuts, and marshmallows need to be coated, the side coverage, due to the wrap around effect, is important. Choosing powders with small particle size, high cohesiveness and high-powder resistivity, and using electrostatic coating can produce food targets coated on all sides.

  8. Novel polymeric film coatings for colon targeting: Drug release from coated pellets.

    PubMed

    Karrout, Youness; Neut, Christel; Wils, Daniel; Siepmann, Florence; Deremaux, Laëtitia; Flament, Marie-Pierre; Dubreuil, Luc; Desreumaux, Pierre; Siepmann, Juergen

    2009-06-28

    The aim of this study was to prepare and characterize novel types of polymer coated pellets allowing for the site-specific delivery of drugs to the colon. 5-Aminosalicylic acid (5-ASA)-loaded beads were prepared by extrusion-spheronization and coated with different Nutriose:ethylcellulose blends. In vitro drug release from these systems was measured under various conditions, including the exposure to fresh fecal samples from inflammatory bowel disease patients under anaerobic conditions. Nutriose is a starch derivative, which is preferentially degraded by enzymes secreted by the microflora in the colon of Crohn's disease and ulcerative colitis patients. Interestingly, the release of 5-ASA (which is commonly used for the local treatment of inflammatory bowel diseases) could effectively be suppressed upon exposure to release media simulating the conditions in the upper GIT, irrespective of the degree of agitation and presence or absence of enzymes. But as soon as the pellets came into contact with fecal samples of inflammatory bowel disease patients, the release rate significantly increased and the drug was released in a time-controlled manner. Thus, this novel type of colon targeting system is adapted to the pathophysiology of the patient. Furthermore, culture media containing specific colonic bacteria are presented providing an interesting potential as substitutes for fresh fecal samples.

  9. Evaluation of present thermal barrier coatings for potential service in electric utility gas turbines

    NASA Technical Reports Server (NTRS)

    Bratton, R. J.; Lau, S. K.; Lee, S. Y.

    1982-01-01

    The resistance of present-day thermal barrier coatings to combustion gases found in electric utility turbines was assessed. The plasma sprayed coatings, both duplex and graded types, were primarily zirconia-based, although a calcium silicate was also evaluated. Both atmospheric burner rig tests and high pressure tests (135 psig) showed that several present-day thermal barrier coatings have a high potential for service in gas turbines burning the relatively clean GT No. 2 fuel. However, coating improvements are needed for use in turbines burning lower grade fuel such as residual oil. The duplex ZrO2.8Y2O3/NiCrA1Y coating was ranked highest and selected for near-term field testing, with Ca2SiO4/NiCrA1Y ranked second. Graded coatings show potential for corrosive turbine operating conditions and warrant further development. The coating degradation mechanisms for each coating system subjected to the various environmental conditions are also described.

  10. Functional coating of liposomes using a folate– polymer conjugate to target folate receptors

    PubMed Central

    Watanabe, Kazuo; Kaneko, Makoto; Maitani, Yoshie

    2012-01-01

    Folate-polymer-coated liposomes were developed for targeted chemotherapy using doxorubicin (DXR) as a model drug. Folate-poly(L-lysine) (F–PLL) conjugates with a folate modification degree of 16.7 mol% on epsilon amino groups of PLL were synthesized. DXR-loaded anionic liposomes were coated with F–PLL, and the cellular association of F–PLL-coated liposomes was evaluated by flow cytometry, and confocal microscopy in human nasopharyngeal carcinoma KB cells overexpressing folate receptors (FRs), and human lung adenocarcinoma A549 cells [FR (−)]. The existence of a polymer layer on the surface of F–PLL-coated liposomes was confirmed by zeta potential analysis. The KB cellular association of F–PLL-coated liposomal DXR was increased compared with that of PLL-coated liposomes and was inhibited in the presence of free folic acid. Twofold higher cytotoxicity of F–PLL-coated liposomal DXR was observed compared with that of the PLL-coated liposomal DXR in KB cells, but not in A549 cells, suggesting the presence of FR-mediated endocytosis. These results indicated that folate-targeted liposomes were prepared successfully by coating the folate–polymer conjugate F–PLL. This novel preparation method of folate-targeted liposomes is expected to provide a powerful tool for the development of a folate-targeting drug nanodevice as coating with ligand–polymer conjugates can be applicable to many kinds of particles, as well as to lipid-based particles. PMID:22888227

  11. Ultrawideband radar target discrimination utilizing an advanced feature set

    NASA Astrophysics Data System (ADS)

    Nguyen, Lam H.; Kapoor, Ravinder; Wong, David C.; Sichina, Jeffrey

    1998-09-01

    The Army Research Laboratory, as part of its mission-funded applied research program, has been evaluating the utility of a low-frequency, ultra wideband imaging radar to detect tactical vehicles concealed by foliage. Measurement programs conducted at Aberdeen Proving Grounds and elsewhere have yielded a significant and unique database of extremely wideband and (in some cases) fully polarimetric data. Prior work has concentrated on developing computationally efficient methods to quickly canvass large quantities of data to identify likely target occurrences--often called `prescreening.' This paper reviews recent findings from our phenomenology/detection efforts. Included is a reformulated prescreener that has been trained and tested against a significantly larger data set than was used in the prior work. Also discussed are initial efforts aimed at the discrimination of targets from the difficult clutter remaining after prescreening. Performance assessments are included that detail detection rates versus false alarm levels.

  12. Versatile surface engineering of porous nanomaterials with bioinspired polyphenol coatings for targeted and controlled drug delivery

    NASA Astrophysics Data System (ADS)

    Li, Juan; Wu, Shuxian; Wu, Cuichen; Qiu, Liping; Zhu, Guizhi; Cui, Cheng; Liu, Yuan; Hou, Weijia; Wang, Yanyue; Zhang, Liqin; Teng, I.-Ting; Yang, Huang-Hao; Tan, Weihong

    2016-04-01

    The development of biocompatible drug delivery systems with targeted recognition and controlled release has experienced a number of design challenges, including, for example, complicated preparation steps and premature drug release. Herein, we address these problems through an in situ self-polymerization method that synthesizes biodegradable polyphenol-coated porous nanomaterials for targeted and controlled drug delivery. As a proof of concept, we synthesized polyphenol-coated mesoporous silica nanoparticles, termed MSN@polyphenol. The polyphenol coatings not only improved colloidal stability and prevented premature drug leakage, but also provided a scaffold for immobilization of targeting moieties, such as aptamers. Both immobilization of targeting aptamers and synthesis of polyphenol coating are easily accomplished without the aid of any other organic reagents. Importantly, the polyphenol coating (EGCg) used in this study could be biodegraded by acidic pH and intracellular glutathione, resulting in the release of trapped anticancer drugs. Based on confocal fluorescence microscopy and cytotoxicity experiments, drug-loaded and polyphenol-coated MSNs were shown to possess highly efficient internalization and an apparent cytotoxic effect on target cancer, but not control, cells. Our results suggest that these highly biocompatible and biodegradable polyphenol-coated MSNs are promising vectors for controlled-release biomedical applications and cancer therapy.The development of biocompatible drug delivery systems with targeted recognition and controlled release has experienced a number of design challenges, including, for example, complicated preparation steps and premature drug release. Herein, we address these problems through an in situ self-polymerization method that synthesizes biodegradable polyphenol-coated porous nanomaterials for targeted and controlled drug delivery. As a proof of concept, we synthesized polyphenol-coated mesoporous silica nanoparticles

  13. Gum arabic-coated magnetic nanoparticles for potential application in simultaneous magnetic targeting and tumor imaging.

    PubMed

    Zhang, Lei; Yu, Faquan; Cole, Adam J; Chertok, Beata; David, Allan E; Wang, Jingkang; Yang, Victor C

    2009-12-01

    Magnetic iron oxide nanoparticles (MNP) coated with gum arabic (GA), a biocompatible phytochemical glycoprotein widely used in the food industry, were successfully synthesized and characterized. GA-coated MNP (GA-MNP) displayed a narrow hydrodynamic particle size distribution averaging about 100 nm; a GA content of 15.6% by dry weight; a saturation magnetization of 93.1 emu/g Fe; and a superparamagnetic behavior essential for most magnetic-mediated applications. The GA coating offers two major benefits: it both enhances colloidal stability and provides reactive functional groups suitable for coupling of bioactive compounds. In vitro results showed that GA-MNP possessed a superior stability upon storage in aqueous media when compared to commercial MNP products currently used in magnetic resonance imaging (MRI). In addition, significant cellular uptake of GA-MNP was evaluated in 9L glioma cells by electron spin resonance (ESR) spectroscopy, fluorescence microscopy, and MRI analyses. Based on these findings, it was hypothesized that GA-MNP might be utilized as a MRI-visible drug carrier in achieving both magnetic tumor targeting and intracellular drug delivery. Indeed, preliminary in vivo investigations validate this clinical potential. MRI visually confirmed the accumulation of GA-MNP at the tumor site following intravenous administration to rats harboring 9L glioma tumors under the application of an external magnetic field. ESR spectroscopy quantitatively revealed a 12-fold increase in GA-MNP accumulation in excised tumors when compared to contralateral normal brain. Overall, the results presented show promise that GA-MNP could potentially be employed to achieve simultaneous tumor imaging and targeted intra-tumoral drug delivery.

  14. Surface properties of semi-synthetic enteric coating films: Opportunities to develop bio-based enteric coating films for colon- targeted delivery

    USDA-ARS?s Scientific Manuscript database

    This study investigated the surface properties of the semi-synthetic enteric coating materials for potential colon- targeted bioactive delivery. The enteric coating materials were produced by combining nanoscale resistant starch, pectin, and carboxymethylcellulose. The surface properties of the co...

  15. Seed coat color and seed weight contribute differential responses of targeted metabolites in soybean seeds.

    PubMed

    Lee, Jinwook; Hwang, Young-Sun; Kim, Sun Tae; Yoon, Won-Byong; Han, Won Young; Kang, In-Kyu; Choung, Myoung-Gun

    2017-01-01

    The distribution and variation of targeted metabolites in soybean seeds are affected by genetic and environmental factors. In this study, we used 192 soybean germplasm accessions collected from two provinces of Korea to elucidate the effects of seed coat color and seeds dry weight on the metabolic variation and responses of targeted metabolites. The effects of seed coat color and seeds dry weight were present in sucrose, total oligosaccharides, total carbohydrates and all measured fatty acids. The targeted metabolites were clustered within three groups. These metabolites were not only differently related to seeds dry weight, but also responded differentially to seed coat color. The inter-relationship between the targeted metabolites was highly present in the result of correlation analysis. Overall, results revealed that the targeted metabolites were diverged in relation to seed coat color and seeds dry weight within locally collected soybean seed germplasm accessions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Apparatus for coating a surface with a metal utilizing a plasma source

    DOEpatents

    Brown, Ian G.; MacGill, Robert A.; Galvin, James E.

    1991-01-01

    An apparatus and method for coating or layering a surface with a metal utilizing a metal vapor vacuum arc plasma source. The apparatus includes a trigger mechanism for actuating the metal vacuum vapor arc plasma source in a pulsed mode at a predetermined rate. The surface or substrate to be coated or layered is supported in position with the plasma source in a vacuum chamber. The surface is electrically biased for a selected period of time during the pulsed mode of operation of the plasma source. Both the pulsing of the metal vapor vacuum arc plasma source and the electrical biasing of the surface are synchronized for selected periods of time.

  17. BN coatings deposition by magnetron sputtering of B and BN targets in electron beam generated plasma

    NASA Astrophysics Data System (ADS)

    Kamenetskikh, A. S.; Gavrilov, N. V.; Koryakova, O. V.; Cholakh, S. O.

    2017-05-01

    Boron nitride coatings were deposited by reactive pulsed magnetron sputtering of B and BN targets (50 kHz, 10 µs for B; 13.56 MHz for BN) at 2-20 mA/cm2 ion current density on the substrate. The effect of electron beam generated plasma on characteristics of magnetron discharge and phase composition of coatings was studied.

  18. Efficiency of utilization of nitrogen coated with urease inhibitor in maize.

    PubMed

    Okumura, Ricardo S; Mariano, Daiane de C; Zaccheo, Paulo V C; de Albuquerque, Amanda N; Giebelmeier, Carmo G; da S Lobato, Allan K; Franco, Antônio A N; de Oliveira, Neto Cândido F; Saldanha, Eduardo C M; da Conceição, Heráclito E O; da Silva, Raimundo T L

    2013-09-01

    This study aimed to evaluate under field conditions the efficiency in the use ofN coated with urease inhibitor in maize. The experiment was conducted in the year of 2007/2008. The experimental design was a randomized block design in a factorial 2 x 6, with five repetitions, constituted the N sources (common and coated with urease inhibitor) and levels (0, 40, 80, 120, 160 and 200 kg ha-1 of N) sidedressing nitrogen application in the growth stage V4. Based on the data obtained were determined recovery efficiencies, utilization, agronomic and physiological N applied. In all cases, the efficiency levels for maize were influenced by levels of sidedressing nitrogen application, in which increasing levels of N resulted in a decrease of the efficiencies, regardless of the source being common urea or coated with urease inhibitor.

  19. Copper-coated laser-fusion targets using molecular-beam levitation

    SciTech Connect

    Rocke, M.J.

    1981-09-08

    A series of diagnostic experiments at the Shiva laser fusion facility required targets of glass microspheres coated with 1.5 to 3.0 ..mu..m of copper. Previous batch coating efforts using vibration techniques gave poor results due to microsphere sticking and vacuum welding. Molecular Beam Levitation (MBL) represented a noncontact method to produce a sputtered copper coating on a single glassmicrosphere. The coating specifications that were achieved resulted in a copper layer up to 3 ..mu..m thick with the allowance of a maximum variation of 10 nm in surface finish and thickness. These techniques developed with the MBL may be applied to sputter coat many soft metals for fusion target applications.

  20. Collagen Coated Nanoliposome as a Targeted and Controlled Drug Delivery System

    NASA Astrophysics Data System (ADS)

    Krishnamoorthy, G.; Stephen, P.; Prabhu, M.; Sehgal, P. K.; Sadulla, S.

    2010-10-01

    The collagen coated nanoliposome (CCNL) have been prepared and characterized in order to develop a targeted and controlled drug delivery system. The zeta potential (ZP) measurement, Fourier transform infrared (FT-IR) spectral and Scanning Electron Microscopy (SEM) and Cell viability assay data showed that the collagen coated nanoliposome particle size and charges, structural interaction and surface morphology and high bio-cyto-compatibility of collagen coated nanoliposome. The particle sizes of nanoliposome (NL) and collagen coated nanoliposome are 20-300 nm and 0.1-10 μm respectively. The introduction of triple helical, coiled coil and fibrous protein of collagen into nanoliposome can improves the stability of nanoliposome, resistant to phospholipase activities and decreasing the phagocytosis of liposomes by reticuloendothelial system. The collagen coated nanoliposome is expected to be used as for targeted and controlled drug delivery system, and tissue engineering application.

  1. Advanced ceramic coating development for industrial/utility gas turbine applications

    NASA Technical Reports Server (NTRS)

    Andersson, C. A.; Lau, S. K.; Bratton, R. J.; Lee, S. Y.; Rieke, K. L.; Allen, J.; Munson, K. E.

    1982-01-01

    The effects of ceramic coatings on the lifetimes of metal turbine components and on the performance of a utility turbine, as well as of the turbine operational cycle on the ceramic coatings were determined. When operating the turbine under conditions of constant cooling flow, the first row blades run 55K cooler, and as a result, have 10 times the creep rupture life, 10 times the low cycle fatigue life and twice the corrosion life with only slight decreases in both specific power and efficiency. When operating the turbine at constant metal temperature and reduced cooling flow, both specific power and efficiency increases, with no change in component lifetime. The most severe thermal transient of the turbine causes the coating bond stresses to approach 60% of the bond strengths. Ceramic coating failures was studied. Analytic models based on fracture mechanics theories, combined with measured properties quantitatively assessed both single and multiple thermal cycle failures which allowed the prediction of coating lifetime. Qualitative models for corrosion failures are also presented.

  2. Influence of natural polymer coating on novel colon targeting drug delivery system.

    PubMed

    Ravi, Valluru; Siddaramaiah; Pramod Kumar, T M

    2008-05-01

    A novel colon targeted tablet formulation was developed using natural polysaccharides such as chitosan and guar gum as carriers and diltiazem hydrochloride as model drug. The prepared blend of polymer-drug tablets were coated with two layers, inulin as an inner coat followed by shellac as outer coat and were evaluated for properties such as average weight, hardness and coat thickness. In vitro release studies of prepared tablets were carried out for 2 h in pH 1.2 HCl buffer, 3 h in pH 7.4 phosphate buffer and 6 h in simulated colonic fluid (SCF) in order to mimic the conditions from mouth to colon. It was observed that 4% w/v of rat cecal contents in saline phosphate buffer (SCF) incubated for 24 h provides suitable conditions for in vitro evaluation of the formulations prepared. The drug release from the coated system was monitored using UV/ Visible spectroscopy. In vitro studies revealed that the tablets coated with inulin and shellac have controlled the drug release in stomach and small intestinal environment and released maximum amount of drug in the colonic environment. Among the polymers used, chitosan was found to be the suitable polymer for colon targeting. The study revealed that polysaccharides as carriers and inulin and shellac as coating materials can be used effectively for colon targeting of drugs for treating local as well as systemic disorders.

  3. Stabilization and target delivery of Nattokinase using compression coating.

    PubMed

    Law, D; Zhang, Z

    2007-05-01

    The aim of the work is to develop a new formulation in order to stabilize a nutraceutical enzyme Nattokinase (NKCP) in powders and to control its release rate when it passes through the gastrointestinal tract of human. NKCP powders were first compacted into a tablet, which was then coated with a mixture of an enteric material Eudragit L100-55 (EL100-55) and Hydroxypropylcellulose (HPC) by direct compression. The activity of the enzyme was determined using amidolytic assay and its release rates in artificial gastric juice and an intestinal fluid were quantified using bicinchoninic acid assay. Results have shown that the activity of NKCP was pressure independent and the coated tablets protected NKCP from being denatured in the gastric juice, and realized its controlled release to the intestine based on in vitro experiments.

  4. Deposition of copper coatings in a magnetron with liquid target

    SciTech Connect

    Tumarkin, A. V. Kaziev, A. V.; Kolodko, D. V.; Pisarev, A. A.; Kharkov, M. M.; Khodachenko, G. V.

    2015-12-15

    Copper coatings were deposited on monocrystalline Si substrates using a magnetron discharge with a liquid cathode in the metal vapour plasma. During the deposition, the bias voltage in the range from 0 V to–400 V was applied to the substrate. The prepared films were investigated by a scanning electron microscope, and their adhesive properties were studied using a scratch tester. It was demonstrated that the adhesion of the deposited films strongly depends on the bias voltage and varies in a wide range.

  5. Non-coated multiparticulate matrix systems for colon targeting.

    PubMed

    Krenzlin, S; Siepmann, F; Wils, D; Guerin-Deremaux, L; Flament, M P; Siepmann, J

    2011-10-01

    Colon specific drug delivery can significantly improve the efficacy of local treatments of inflammatory bowel diseases. Film coatings containing the starch derivative Nutriose have recently been reported to minimize 5-ASA release in media simulating the upper gastro intestinal tract (GIT), while releasing the drug in a time-controlled manner upon contact with feces from Crohn's Disease and Ulcerative Colitis patients. It was the aim of this study to prepare Nutriose-containing matrix pellets and mini tablets in order to avoid a film coating step. Highly dosed matrix pellets were prepared by extrusion-spheronization, highly dosed mini tablets by compression. Various types of lipids were added and drug release measured in 0.1 N HCl and phosphate buffer pH 6.8, optionally containing pepsin and pancreatin. The type of added lipid and the preparation technique, in particular the curing conditions, significantly affected the resulting drug release kinetics. Glyceryl palmitostearate containing pellets and mini tablets showed the most promising results upon appropriate curing, minimizing premature drug release in media simulating the upper GIT. The proposed novel multiparticulates do not require a film coating step and show an interesting potential for site-specific drug delivery to the colon of inflammatory bowel disease patients.

  6. Hot corrosion of ceramic-coating materials for industrial/utility gas turbines

    SciTech Connect

    Barkalow, R.H.

    1981-01-01

    Furnace hot corrosion tests of yttria-stabilized zirconia (YSZ) and other candidate ceramic coating materials were run under combinations of temperature, salt deposits, and gaseous environments know to cause severe hot corrosion of state-of-the-art metallic coatings for industrial/utility gas turbines. Specimens were free-standing ceramic coupons and ceramic-coated IN 792. X-ray fluorescence and diffraction data on free-standing YSZ coupons showed surface yttrium loss and cubic-to-monoclinic transformation as a result of exposure to liquid salt and SO/sub 3/. Greater destabilization was observed at the lower of two test temperatures (704 and 982/sup 0/C), and destabilization increased with increasing SO/sub 3/ pressure and V-containing salt deposits. The data suggest that hot corrosion of YSZ can occur by a type of acidic dissolution of Y/sub 2/O/sub 3/ from the ZrO/sub 2/ solid solution. In spite of the greater surface destabilization at 704/sup 0/C, the bond coat and substrate of YSZ-coated IN 792 were not attacked at 704/sup 0/C but severely corroded at 982/sup 0/C. These results show that degradation of ceramic-coated metallic components can be more strongly influenced by the porosity of the microstructure and fluidity of the liquid salt than by the chemical stability of the ceramic coating material in the reactive environment. Other ceramic materials (SiO/sub 2/, Si/sub 3/N/sub 4/, ZrSiO/sub 2/, and mullite), concurrently exposed to the same conditions which produced significant destabilization of YSZ, showed no evidence of reaction at 704/sup 0/C but noticeable corrosion at 982/sup 0/C. Also, the high temperature corrosion was greater in air than in SO/sub 3/-containing gases. These trends suggest that hot corrosion of the silicon-containing ceramics was basic in nature, and such materials have potential for good resistance to chemical decomposition under the acidic conditions characteristics of industrial/utility gas turbines.

  7. High Performance Optical Coatings Utilizing Tailored Refractive Index Nanoporous Thin Films

    NASA Astrophysics Data System (ADS)

    Poxson, David J.

    Refractive index is perhaps the most important quantity in optics. It is particularly relevant in the field of optical coatings, where the refractive index appears in virtually every optics equation as a figure of merit. Recently it has been demonstrated through control of the deposition angle during oblique-angle electron-beam deposition, nanoporous films of virtually any desired porosity may be accurately deposited. As the porosity of a nanoporous film directly relates to its effective refractive index, the refractive index value of a film may be tailored to any value between that of the bulk material and close to that of air. These two characteristics, namely; (i) tailored-refractive index and (ii) very low-refractive index values close to that of air, offer significant advantages in the design and optical performance in all optical coating applications. In this dissertation we explore optical coating applications whose performance can be greatly enhanced by utilization of a tailored- and low-refractive index nanoporous material system. One such important application is in the design and fabrication of broadband, omnidirectional antireflection (AR) coatings on solar cell devices. To harness the full spectrum of solar energy, Fresnel reflections at the surface of a photovoltaic cell must be reduced as much as possible over the relevant solar wavelength range and over a wide range of incident angles. However, the development of AR coatings embodying omni-directionality over a wide range of wavelengths is challenging. By utilizing the tailored- and low-refractive index properties of the nanoporous material system, in conjunction with a computational genetic algorithm and a predictive quantitative model for the porosity of such nanoporous films, truly optimized AR coatings can be designed and fabricated on solar cells. Here we show that these optimized AR structures demonstrate significant improvement to overall device efficiency. Traditionally, nanoporous films

  8. Apparatus for coating a surface with a metal utilizing a plasma source

    DOEpatents

    Brown, I.G.; MacGill, R.A.; Galvin, J.E.

    1991-05-07

    An apparatus and method are disclosed for coating or layering a surface with a metal utilizing a metal vapor vacuum arc plasma source. The apparatus includes a trigger mechanism for actuating the metal vacuum vapor arc plasma source in a pulsed mode at a predetermined rate. The surface or substrate to be coated or layered is supported in position with the plasma source in a vacuum chamber. The surface is electrically biased for a selected period of time during the pulsed mode of operation of the plasma source. Both the pulsing of the metal vapor vacuum arc plasma source and the electrical biasing of the surface are synchronized for selected periods of time. 10 figures.

  9. Multilayer Thermal Barrier Coating (TBC) Architectures Utilizing Rare Earth Doped YSZ and Rare Earth Pyrochlores

    NASA Technical Reports Server (NTRS)

    Schmitt, Michael P.; Rai, Amarendra K.; Bhattacharya, Rabi; Zhu, Dongming; Wolfe, Douglas E.

    2014-01-01

    To allow for increased gas turbine efficiencies, new insulating thermal barrier coatings (TBCs) must be developed to protect the underlying metallic components from higher operating temperatures. This work focused on using rare earth doped (Yb and Gd) yttria stabilized zirconia (t' Low-k) and Gd2Zr2O7 pyrochlores (GZO) combined with novel nanolayered and thick layered microstructures to enable operation beyond the 1200 C stability limit of current 7 wt% yttria stabilized zirconia (7YSZ) coatings. It was observed that the layered system can reduce the thermal conductivity by approximately 45 percent with respect to YSZ after 20 hr of testing at 1316 C. The erosion rate of GZO is shown to be an order to magnitude higher than YSZ and t' Low-k, but this can be reduced by almost 57 percent when utilizing a nanolayered structure. Lastly, the thermal instability of the layered system is investigated and thought is given to optimization of layer thickness.

  10. Single cell targeting using plasmon resonant gold-coated liposomes

    NASA Astrophysics Data System (ADS)

    Leung, Sarah J.; Romanowski, Marek

    2012-03-01

    We have developed an experimental system with the potential for the delivery and localized release of an encapsulated agent with high spatial and temporal resolution. We previously introduced liposome-supported plasmon resonant gold nanoshells; in this composite structure, the liposome allows for the encapsulation of substances, such as therapeutic agents, neurotransmitters, or growth factors, and the plasmon resonant structure facilitates the rapid release of encapsulated contents upon laser light illumination. More recently, we demonstrated that these gold-coated liposomes are capable of releasing their contents in a spectrally-controlled manner, where plasmon resonant nanoparticles only release content upon illumination with a wavelength of light matching their plasmon resonance band. We now show that this release mechanism can be used in a biological setting to deliver a peptide derivative of cholecystokinin to HEK293 cells overexpressing the CCK2 receptor. Using directed laser light, we may enable localized release from gold-coated liposomes to enable accurate perturbation of cellular functions in response to released compounds; this system may have possible applications in signaling pathways and drug discovery.

  11. Gold Coated Lanthanide Phosphate Nanoparticles for Targeted Alpha Generator Radiotherapy

    SciTech Connect

    McLaughlin, Mark F; Woodward, Jonathan; Boll, Rose Ann; Wall, Jonathan; Rondinone, Adam Justin; Kennel, Steve J; Mirzadeh, Saed; Robertson, David J.

    2013-01-01

    Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo generators such as 225Ac, which emits four particles in its decay chain, can significantly amplify the radiation dose delivered to the target site. However, renal dose from unbound 213Bi escaping during the decay process limits the dose of 225Ac that can be administered. Traditional chelating moieties are unable to sequester the radioactive daughters because of the high recoil energy from alpha particle emission. To counter this, we demonstrate that an engineered multilayered nanoparticle-antibody conjugate can both deliver radiation and contain the decay daughters of the in vivo -generator 225Ac while targeting biologically relevant receptors. These multi-shell nanoparticles combine the radiation resistance of crystalline lanthanide phosphate to encapsulate and contain 225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established surface chemistry of gold for attachment of nanoparticles to targeting antibodies.

  12. Gold Coated Lanthanide Phosphate Nanoparticles for Targeted Alpha Generator Radiotherapy

    PubMed Central

    McLaughlin, Mark F.; Woodward, Jonathan; Boll, Rose A.; Wall, Jonathan S.; Rondinone, Adam J.; Kennel, Stephen J.; Mirzadeh, Saed; Robertson, J. David

    2013-01-01

    Targeted radiotherapies maximize cytotoxicty to cancer cells. In vivo α-generator targeted radiotherapies can deliver multiple α particles to a receptor site dramatically amplifying the radiation dose delivered to the target. The major challenge with α-generator radiotherapies is that traditional chelating moieties are unable to sequester the radioactive daughters in the bioconjugate which is critical to minimize toxicity to healthy, non-target tissue. The recoil energy of the 225Ac daughters following α decay will sever any metal-ligand bond used to form the bioconjugate. This work demonstrates that an engineered multilayered nanoparticle-antibody conjugate can deliver multiple α radiations and contain the decay daughters of 225Ac while targeting biologically relevant receptors in a female BALB/c mouse model. These multi-shell nanoparticles combine the radiation resistance of lanthanide phosphate to contain 225Ac and its radioactive decay daughters, the magnetic properties of gadolinium phosphate for easy separation, and established gold chemistry for attachment of targeting moieties. PMID:23349921

  13. Bypassing Protein Corona Issue on Active Targeting: Zwitterionic Coatings Dictate Specific Interactions of Targeting Moieties and Cell Receptors.

    PubMed

    Safavi-Sohi, Reihaneh; Maghari, Shokoofeh; Raoufi, Mohammad; Jalali, Seyed Amir; Hajipour, Mohammad J; Ghassempour, Alireza; Mahmoudi, Morteza

    2016-09-07

    Surface functionalization strategies for targeting nanoparticles (NP) to specific organs, cells, or organelles, is the foundation for new applications of nanomedicine to drug delivery and biomedical imaging. Interaction of NPs with biological media leads to the formation of a biomolecular layer at the surface of NPs so-called as "protein corona". This corona layer can shield active molecules at the surface of NPs and cause mistargeting or unintended scavenging by the liver, kidney, or spleen. To overcome this corona issue, we have designed biotin-cysteine conjugated silica NPs (biotin was employed as a targeting molecule and cysteine was used as a zwitterionic ligand) to inhibit corona-induced mistargeting and thus significantly enhance the active targeting capability of NPs in complex biological media. To probe the targeting yield of our engineered NPs, we employed both modified silicon wafer substrates with streptavidin (i.e., biotin receptor) to simulate a target and a cell-based model platform using tumor cell lines that overexpress biotin receptors. In both cases, after incubation with human plasma (thus forming a protein corona), cellular uptake/substrate attachment of the targeted NPs with zwitterionic coatings were significantly higher than the same NPs without zwitterionic coating. Our results demonstrated that NPs with a zwitterionic surface can considerably facilitate targeting yield of NPs and provide a promising new type of nanocarriers in biological applications.

  14. Matrix Pre-coated Targets for High Throughput MALDI Imaging of Proteins

    PubMed Central

    Yang, Junhai; Caprioli, Richard M.

    2014-01-01

    We have developed matrix pre-coated targets for imaging proteins in thin tissue sections by MALDI MS (matrix-assisted laser desorption/ionization mass spectrometry). Gold covered microscope slides were coated with sinapinic acid (SA) in batches in advance and were shown to be stable for over 6 months when kept in the dark. The sample preparation protocol using these SA pre-coated targets involves treatment with diisopropylethylamine (DIEA)-H2O vapor, transforming the matrix layer to a viscous ionic liquid. This SA-DIEA ionic liquid layer extracts proteins and other analytes from tissue sections that are thaw mounted to this target. DIEA is removed by immersion of the target into diluted acetic acid (AcOH), allowing SA to co-crystallizes with extracted analytes directly on the target. Ion images (3–70 kDa) of sections of mouse brain and rat kidney at spatial resolution down to 10 μm were obtained. Use of pre-coated slides greatly reduces sample preparation time for MALDI imaging while providing high throughput, low cost, and high spatial resolution images. PMID:24809903

  15. Metal-containing plasma-polymerized coatings for laser-fusion targets

    SciTech Connect

    Letts, S.A.; Jordan, C.W.

    1981-09-14

    Addition of metal to plastic layers in some direct drive laser fusion targets is needed to reduce electron induced fuel preheat. A plasma polymerization coating system was constructed to produce a metal seeded polymer by adding an organometallic gas to the usual trans-2-butene and hydrogen feedstocks. Since organometallic gases are highly reactive and toxic, safety is a major concern in the design of a coating system. Our coating apparatus was designed with three levels of containment to assure protection of the operator. The gas handling system has redundant valves and was designed to fail safe. Several sensor controlled interlocks assure safe operating conditions. Waste materials are collected on a specially designed cold trap. Waste disposal is accomplished by heating the traps and purging volatile products through a reactor vessel. The design, operating procedure, and safety interlocks of this novel coating system are described.

  16. Utility of network integrity methods in therapeutic target identification

    PubMed Central

    Peng, Qian; Schork, Nicholas J.

    2013-01-01

    Analysis of the biological gene networks involved in a disease may lead to the identification of therapeutic targets. Such analysis requires exploring network properties, in particular the importance of individual network nodes (i.e., genes). There are many measures that consider the importance of nodes in a network and some may shed light on the biological significance and potential optimality of a gene or set of genes as therapeutic targets. This has been shown to be the case in cancer therapy. A dilemma exists, however, in finding the best therapeutic targets based on network analysis since the optimal targets should be nodes that are highly influential in, but not toxic to, the functioning of the entire network. In addition, cancer therapeutics targeting a single gene often result in relapse since compensatory, feedback and redundancy loops in the network may offset the activity associated with the targeted gene. Thus, multiple genes reflecting parallel functional cascades in a network should be targeted simultaneously, but require the identification of such targets. We propose a methodology that exploits centrality statistics characterizing the importance of nodes within a gene network that is constructed from the gene expression patterns in that network. We consider centrality measures based on both graph theory and spectral graph theory. We also consider the origins of a network topology, and show how different available representations yield different node importance results. We apply our techniques to tumor gene expression data and suggest that the identification of optimal therapeutic targets involving particular genes, pathways and sub-networks based on an analysis of the nodes in that network is possible and can facilitate individualized cancer treatments. The proposed methods also have the potential to identify candidate cancer therapeutic targets that are not thought to be oncogenes but nonetheless play important roles in the functioning of a cancer

  17. Utility of network integrity methods in therapeutic target identification.

    PubMed

    Peng, Qian; Schork, Nicholas J

    2014-01-01

    Analysis of the biological gene networks involved in a disease may lead to the identification of therapeutic targets. Such analysis requires exploring network properties, in particular the importance of individual network nodes (i.e., genes). There are many measures that consider the importance of nodes in a network and some may shed light on the biological significance and potential optimality of a gene or set of genes as therapeutic targets. This has been shown to be the case in cancer therapy. A dilemma exists, however, in finding the best therapeutic targets based on network analysis since the optimal targets should be nodes that are highly influential in, but not toxic to, the functioning of the entire network. In addition, cancer therapeutics targeting a single gene often result in relapse since compensatory, feedback and redundancy loops in the network may offset the activity associated with the targeted gene. Thus, multiple genes reflecting parallel functional cascades in a network should be targeted simultaneously, but require the identification of such targets. We propose a methodology that exploits centrality statistics characterizing the importance of nodes within a gene network that is constructed from the gene expression patterns in that network. We consider centrality measures based on both graph theory and spectral graph theory. We also consider the origins of a network topology, and show how different available representations yield different node importance results. We apply our techniques to tumor gene expression data and suggest that the identification of optimal therapeutic targets involving particular genes, pathways and sub-networks based on an analysis of the nodes in that network is possible and can facilitate individualized cancer treatments. The proposed methods also have the potential to identify candidate cancer therapeutic targets that are not thought to be oncogenes but nonetheless play important roles in the functioning of a cancer

  18. Enhanced brain targeting of temozolomide in polysorbate-80 coated polybutylcyanoacrylate nanoparticles

    PubMed Central

    Tian, Xin-Hua; Lin, Xiao-Ning; Wei, Feng; Feng, Wei; Huang, Zhi-Chun; Wang, Peng; Ren, Lei; Diao, Yi

    2011-01-01

    Background: Polybutylcyanoacrylate (PBCA) nanoparticles coated with polysorbate-80 have been extensively proposed for delivering drugs into the animal brain and have shown great potential for therapeutic applications. In this study, we made an attempt to deliver the chemotherapeutic drug, temozolomide, into the brain by using PBCA nanoparticles. The physicochemical characteristics, in vitro release, and brain targeting ability of the drug-loaded nanoparticles were investigated. Results: Our results show that a significantly higher concentration of temozolomide in the form of polysorbate-80-coated PBCA nanoparticles was observed in the brain (P < 0.05) in comparison with the free drug. Conclusion: This study indicates that polysorbate-80 coated PBCA nanoparticles could be a feasible carrier for temozolomide delivery to the brain. It is anticipated that the developed formulation may improve on targeted therapy for malignant brain tumors in the future. PMID:21445277

  19. A technique for thick polymer coating of inertial-confinement-fusion targets

    NASA Technical Reports Server (NTRS)

    Lee, M. C.; Feng, I.-A.; Wang, T. G.; Kim, H.-G.

    1983-01-01

    A technique to coat a stalk-mounted inertial-confinement fusion (ICF) target with a thick polymer layer has been successfully demonstrated. The polymer solution is first atomized, allowed to coalesce into a droplet, and positioned in a stable acoustic levitating field. The stalk-mounted ICF target is then moved into the acoustic field by manipulating a 3-D positioner to penetrate the surface membrane of the droplet, thus immersing the target in the levitated coating solution. The target inside the droplet is maintained at the center of the levitated liquid using the 3-D positional information provided by two orthogonally placed TV cameras until the drying process is completed. The basic components of the experimental apparatus, including an acoustic levitator, liquid sample deployment device, image acquisition instrumentation, and 3-D positioner, are briefly described.

  20. A technique for thick polymer coating of inertial-confinement-fusion targets

    NASA Technical Reports Server (NTRS)

    Lee, M. C.; Feng, I.-A.; Wang, T. G.; Kim, H.-G.

    1983-01-01

    A technique to coat a stalk-mounted inertial-confinement fusion (ICF) target with a thick polymer layer has been successfully demonstrated. The polymer solution is first atomized, allowed to coalesce into a droplet, and positioned in a stable acoustic levitating field. The stalk-mounted ICF target is then moved into the acoustic field by manipulating a 3-D positioner to penetrate the surface membrane of the droplet, thus immersing the target in the levitated coating solution. The target inside the droplet is maintained at the center of the levitated liquid using the 3-D positional information provided by two orthogonally placed TV cameras until the drying process is completed. The basic components of the experimental apparatus, including an acoustic levitator, liquid sample deployment device, image acquisition instrumentation, and 3-D positioner, are briefly described.

  1. The Effect of Condensates and Inner Coatings on the Performance of Vacuum Hohlraum Targets

    SciTech Connect

    Boehly, T.R.; Olson, R.E.; Celliers, P.M.; Munro, D.H.; Seka, W.; Landen, O.L.; Collins, G.W.; Suter, L.J.; Sangster, T.C.; Meyerhofer, D.D.

    2010-03-23

    Experiments on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)] using laser-driven vacuum hohlraum targets show distinct differences between cryogenic (<20 K) and warm targets. The cryogenic targets have 15% lower peak radiation temperatures, and the temporal profile of those temperatures is quite different than in warm targets. The cryogenic targets reflect significantly more (3%–7%) of the laser drive than the warm targets (<1%). The temporal and spectral features of the reflected light from the cryogenic targets show a significantly longer duration and more spectral features than the warm hohlraums. Warm hohlraum targets coated with 2 um of CH replicate the behavior of cryogenic targets. This indicates that the cryogenic hohlraums are affected by the condensation of background gases on the cold hohlraum surface. The most important effect of low-Z material in the hohlraums is that they significantly reduce the x-ray conversion efficiency, resulting in lower hohlraum radiation temperature. The coatings (both CH and condensates) produce long-scale-length, low-Z plasmas that moderately reduce the absorption of laser light in the hohlraums. This causes higher reflectivity and produces hot electrons that generate hard x rays (hv > 20 keV), both of which are detrimental to the performance of hohlraum-driven inertial confinement fusion targets.

  2. Hyaluronic acid-coated liposomes for active targeting of gemcitabine.

    PubMed

    Arpicco, Silvia; Lerda, Carlotta; Dalla Pozza, Elisa; Costanzo, Chiara; Tsapis, Nicolas; Stella, Barbara; Donadelli, Massimo; Dando, Ilaria; Fattal, Elias; Cattel, Luigi; Palmieri, Marta

    2013-11-01

    The aim of this work was the preparation, characterization, and preliminary evaluation of the targeting ability toward pancreatic adenocarcinoma cells of liposomes containing the gemcitabine lipophilic prodrug [4-(N)-lauroyl-gemcitabine, C12GEM]. Hyaluronic acid (HA) was selected as targeting agent since it is biodegradable, biocompatible, and can be chemically modified and its cell surface receptor CD44 is overexpressed on various tumors. For this purpose, conjugates between a phospholipid, the 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), and HA of two different low molecular weights 4800 Da (12 disaccharidic units) and 12,000 Da (32 disaccharidic units), were prepared, characterized, and introduced in the liposomes during the preparation. Different liposomal formulations were prepared and their characteristics were analyzed: size, Z potential, and TEM analyses underline a difference in the HA-liposomes from the non-HA ones. In order to better understand the HA-liposome cellular localization and to evaluate their interaction with CD44 receptor, confocal microscopy studies were performed. The results demonstrate that HA facilitates the recognition of liposomes by MiaPaCa2 cells (CD44(+)) and that the uptake increases with increase in the polymer molecular weight. Finally, the cytotoxicity of the different preparations was evaluated and data show that incorporation of C12GEM increases their cytotoxic activity and that HA-liposomes inhibit cell growth more than plain liposomes. Altogether, the results demonstrate the specificity of C12GEM targeting toward CD44-overexpressing pancreatic adenocarcinoma cell line using HA as a ligand.

  3. Targeting of human glioma xenografts in vivo utilizing radiolabeled antibodies

    SciTech Connect

    Williams, J.A.; Wessels, B.W.; Wharam, M.D.; Order, S.E.; Wanek, P.M.; Poggenburg, J.K.; Klein, J.L. )

    1990-06-01

    Radiolabeled antibodies provide a potential basis for selective radiotherapy of human gliomas. We have measured tumor targeting by radiolabeled monoclonal and polyclonal antibodies directed against neuroectodermal and tumor-associated antigens in nude mice bearing human glioma xenografts. Monoclonal P96.5, a mouse IgG2a immunoglobulin, defines an epitope of a human melanoma cell surface protein, and specifically binds the U-251 human glioma as measured by immunoperoxidase histochemistry. 111In-radiolabeled P96.5 specifically targets the U-251 human glioma xenograft and yields 87.0 microCuries (microCi) of tumor activity per gram per 100 microCi injected activity compared to 4.5 microCi following administration of radiolabeled irrelevant monoclonal antibody. Calculations of targeting ratios demonstrate deposited dose to be 11.6 times greater with radiolabeled P96.5 administration compared to irrelevant monoclonal antibody. The proportion of tumor dose found in normal organs is less than 10%, further supporting specific targeting of the human glioma xenograft by this antibody. Monoclonal antibody ZME018, which defines a second melanoma-associated antigen, and polyclonal rabbit antiferritin, which defines a tumor-associated antigen, demonstrate positive immunoperoxidase staining of the tumor, but comparatively decreased targeting. When compared to the 111In-radiolabeled antibody, 90Y-radiolabeled P96.5 demonstrates comparable tumor targeting and percentages of tumor dose found in normal organs. To test the therapeutic potential of 90Y-radiolabeled P96.5, tumors and normal sites were implanted with miniature thermoluminescent dosimeters (TLD). Seven days following administration of 100 microCi 90Y-radiolabeled P96.5, average absorbed doses of 3770, 980, 353, and 274 cGy were observed in tumor, liver, contralateral control site, and total body, respectively.

  4. Drug embedded PVP coated magnetic nanoparticles for targeted killing of breast cancer cells.

    PubMed

    Rose, P Arsula; Praseetha, P K; Bhagat, Madhulika; Alexander, Princy; Abdeen, Sunitha; Chavali, Murthy

    2013-10-01

    Magnetic drug targeting is a drug delivery system that can be used in loco-regional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by co-precipitation of iron oxide followed by coating with polyvinyl pyrrolidone (PVP). Characterization was performed using X-ray diffraction, TEM, TGA, FTIR and UV-Vis Spectroscopy. Magnetite (Fe3O4) remained as the core of the carrier. The amount of PVP bound to the iron oxide nanoparticles was estimated by thermogravimetric analysis (TGA) and the attachment of PVP to the iron oxide nanoparticles confirmed by FTIR analysis. The loading efficiency of Epirubicin hydrochloride onto the PVP coated and uncoated iron oxide nanoparticles was measured at intervals such as 1 hr and 24 hrs by UV-Vis Spectroscopy. The binding of Epirubicin hydrochloride to the PVP coated and uncoated iron oxide nanoparticles were confirmed by FTIR analysis. The present findings showed that Epirubicin hydrochloride loaded PVP coated iron oxide nanoparticles are promising for magnetically targeted drug delivery. The drug displayed increased cell cytotoxicity at lower concentrations when conjugated with the nanoparticles than being administered conventionally as individual drugs.

  5. Targeting of vaccinia virus using biotin-avidin viral coating and biotinylated antibodies.

    PubMed

    Purow, Benjamin; Staveley-O'Carroll, Kevin

    2005-01-01

    To test a general method for altering the tropism of viral vectors, we conjugated targeting antibody to the surface of recombinant vaccinia virus with a biotin-avidin-biotin linker and assessed the resulting infectivity in target cells and controls. We biotinylated a vaccinia viral vector and used avidin to crosslink the biotinylated viral surface to a biotinylated antibody specific for a molecule on the surface of a target cell. In an in vitro model system, we coated a recombinant vaccinia construct containing the E. coli beta-galactosidase gene with antibody to the murine class I MHC molecule Db. Target cells were B78H1 murine melanoma cells transduced with either the Db gene or, as a control, the Kb gene. Infectivity was assessed by staining target cells with x-gal to demonstrate expression of virally delivered beta-galactosidase. This technique was also assessed in a second system with vaccinia/beta-gal targeted to the murine B7.2 molecule. The infectivity of the resulting construct was assessed for murine SA1 fibrosarcoma cells transfected with the B7.2 gene and for wild-type, B7.2-negative SA1. Experiments were repeated in each system with similar results. This strategy demonstrated antibody-mediated viral targeting in both the B78H1 and the SA1 models. Importantly, addition of the targeting coat diminished the infectivity of the modified vaccinia for control cells but preserved infectivity for targeted cells. In the B78H1 system, Db-targeted vaccinia consistently had 2- to 3-fold greater infectivity for B78H1Db than B78H1Kb. Increasing the number of avidin molecules used per virion in the synthesis of the viral coat led to greater selectivity but decreased overall infectivity. In the SA1 system, B7.2-targeted vaccinia demonstrated completely ablated infectivity for control SA1 cells, but maintained infectivity for target SA1/B7.2 cells. Recombinant viral vectors such as vaccinia may be coated with biotin/avidin and linked to biotinylated antibodies to

  6. Utilization of calcium carbonate particles from eggshell waste as coating pigments for ink-jet printing paper.

    PubMed

    Yoo, Sukjoon; Hsieh, Jeffery S; Zou, Peter; Kokoszka, John

    2009-12-01

    The effective treatment and utilization of biowaste have been emphasized in our society for environmental and economic concerns. Recently, the eggshell waste in the poultry industry has been highlighted because of its reclamation potential. This study presents an economical treatment process to recover useful bioproducts from eggshell waste and their utilization in commercial products. We developed the dissolved air floatation (DAF) separation unit, which successfully recovered 96% of eggshell membrane and 99% of eggshell calcium carbonate (ECC) particles from eggshell waste within 2 h of operation. The recovered ECC particles were utilized as coating pigments for ink-jet printing paper and their impact on the ink density and paper gloss were investigated. The addition of the ECC particles as coating pigments enhances the optical density of cyan, magenta and yellow inks while decreasing the black ink density and the gloss of the coated paper.

  7. Biocompatible hyaluronic acid polymer-coated quantum dots for CD44+ cancer cell-targeted imaging

    NASA Astrophysics Data System (ADS)

    Wang, Hening; Sun, Hongfang; Wei, Hui; Xi, Peng; Nie, Shuming; Ren, Qiushi

    2014-10-01

    The cysteamine-modified hyaluronic acid (HA) polymer was employed to coat quantum dots (QDs) through a convenient one-step reverse micelle method, with the final QDs hydrodynamic size of around 22.6 nm. The HA coating renders the QDs with very good stability in PBS for more than 140 days and resistant to large pH range of 2-12. Besides, the HA-coated QDs also show excellent fluorescence stability in BSA-containing cell culture medium. In addition, the cell culture assay indicates no significant cytotoxicity for MD-MB-231 breast cancer cells, and its targeting ability to cancer receptor CD44 has been demonstrated on two breast cancer cell lines. The targeting mechanism was further proved by the HA competition experiment. This work has established a new approach to help solve the stability and toxicity problems of QDs, and moreover render the QDs cancer targeting property. The current results indicate that the HA polymer-coated QDs hold the potential application for both in vitro and in vivo cancer imaging researches.

  8. A new targeted delivery approach by functionalizing drug nanocrystals through polydopamine coating.

    PubMed

    Zhan, Honglei; Jagtiani, Tina; Liang, Jun F

    2017-05-01

    Tumor target specificity via chemotherapy is widely considered to be very effective on tumor treatment. For an ideal chemotherapeutic agent like Camptothecin (CPT) (CPT is the abbreviation for Camptothecin), improved therapeutic efficacy and high selectivity are equally important. Inspired by adhesive proteins in mussels, here we developed a novel tumor targeting peptide XQ1 grafted CPT nanocrystals with polydopamine coating as a spacer. In this study, CPT nanocrystals were coated by polymerization of dopamine that was induced by plasma-activated water under an acidic environment, and then the tumor targeting peptide was grafted onto polydopamine (PDA) (PDA is the abbreviation for polydopamine) coated CPT nanocrystals through catechol chemistry. The PDA layer had negligible effects on drug crystallinity and structure but resulted in drug nanocrystals with excellent dispersion properties, improved dissolution rate and drug stability by preventing water hydrolysis. More importantly, tumor targeting peptide XQ1 facilitated a rapid cross-membrane translocation of drug nanocrystals via receptor-mediated endocytosis, leading to efficient intracellular drug delivery. Moreover, this novel drug formulation demonstrated more potent anti-cancer activity against tumor cells in comparison with free CPT and naked CPT nanocrystals and exhibited high selectivity, all of which are attributed to the tumor target specificity property and inherent pH-dependent drug release behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Multi-Response Optimization of Process Parameters for Low-Pressure Cold Spray Coating Process Using Taguchi and Utility Concept

    NASA Astrophysics Data System (ADS)

    Goyal, Tarun; Sidhu, T. S.; Walia, R. S.

    2014-01-01

    Most of the existing multi-response optimization approaches focus on the subjective and practical know-how of the process. As a result, some confusion and uncertainty are introduced in the overall decision-making process. In this work, an approach based on a Utility theory and Taguchi quality loss function has been applied to the process parameters for low-pressure cold spray process deposition of copper coatings, for simultaneous optimization of more than one response characteristics. In the present paper, two potential response parameters, i.e., coating thickness and coating density, have been selected. Utility values based on these response parameters have been analyzed for optimization using the Taguchi approach. The selected input parameters of powder feeding arrangement, substrate material, air stagnation pressure, air stagnation temperature, and stand-off distance significantly improve the Utility function (raw data) comprising quality characteristics (coating thickness and coating density). The percentage contribution of the parameters to achieve a higher value of Utility function is substrate material (50.03%), stand-off distance (28.87%), air stagnation pressure (6.41%), powder feeding arrangement (4.68%), and air stagnation temperature (2.64%).

  10. Evaluation of extended-release applications for solid dispersion hot-melt fluid bed coatings utilizing hydrophobic coating agents.

    PubMed

    Kennedy, J P; Niebergall, P J

    1998-02-01

    A new hot-melt fluid bed coating method was evaluated for potential extended-release applications. Chlorpheniramine maleate (CPM) USP was chosen as a model drug. The assays for drug release and content uniformity were dictated by the USP Official Monograph for a Chlorpheniramine Maleate Extended-Release Capsule. The fluid bed chamber was charged with CPM-loaded nonpareils and hydrophobic coating agents in the solid state. The method consists of four processing stages: (a) warming, (b) preheating, (c) melting-spreading, and (d) cooling-congealing. Various hydrophobic coating agent candidates were evaluated for extended-release potential by a preliminary screen at a coating agent level of 1.5% (w/w). A beeswax coating agent was identified as the most promising candidate of the preliminary screen. After the level of beeswax was increased to 2.0%, the dissolution profile met all of the specifications of the USP Drug Release Test 1 for a CPM Extended-Release Capsule. The potency and content uniformity remained unchanged by the process. Dual coatings demonstrated a cumulative extension of release superior to the capability of a single coat. The new method is a viable alternative to hot-melt spray-coating methodologies. Organic solvents, spraying equipment, steam jackets, and/or heating tape are eliminated from the process. A reduction of equipment costs, setup time, and cleanup time may be realized. The method has demonstrated extended-release capabilities. No excessive attrition of potency or content uniformity has been noted. Additive, multiple coatings that have a cumulative effect on release retardation are feasible.

  11. Coatings.

    ERIC Educational Resources Information Center

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  12. Coatings.

    ERIC Educational Resources Information Center

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  13. Plasma-flash radiography utilizing a molybdenum target in dentistry

    SciTech Connect

    Yamamoto, Mariko; Takabe, Akihito; Sakamaki, Kimio

    1995-12-31

    The construction and the radiographic characteristics of a plasma flash x-ray generator having a molybdenum-target (anode tip) triode are described. This generator was primarily designed in order to perform soft radiography in dental medicine and employed the following essential components: a high-voltage power supply, a low-impedance coaxial transmission line with a gap switch, a coaxial oil condenser of 0.2 {micro}F, a turbo-molecular pump, a Krytron pulser as a trigger device, and a flash x-ray tube. The high-voltage main condenser of 0.2 {micro}F was charged from 40 to 60 kV by the power supply, and the electric charges in the condenser were discharged to the tube after closing the gap switch. Because this tube employed a long target, the plasma x-ray source which consists of molybdenum ions and electrons was easily produced by the target evaporating. The maximum tube voltage was nearly equivalent to the initial charging voltage of the main condenser, and the maximum current had a value of about 25 kA with a charging voltage of 60 kV. The average width of flash x rays was less than 1 {micro}s, and the time-integrated x-ray intensity with a charging voltage of 60 kV was approximately 20 {micro}C/kg at 1.0 m per pulse. The characteristic K-series intensity substantially increased according to increases in the charging voltage. High-speed dental radiography was performed by using a laser timing switch and a trigger-delay device.

  14. Plasma-flash radiography utilizing a molybdenum target in dentistry

    NASA Astrophysics Data System (ADS)

    Yamamoto, Mariko; Takabe, Akihito; Sakamaki, Kimio; Sato, Eiichi; Takahashi, Kei; Sagae, Michiaki; Oizumi, Teiji; Hayasi, Yasuomi; Sasaki, Katsuaki; Tamakawa, Yoshiharu; Yanagisawa, Toru

    1995-09-01

    The construction and the radiographic characteristics of a plasma flash x-ray generator having a molybdenum-target (anode tip) triode are described. This generator was primarily designed in order to perform soft radiography in dental medicine and employed the following essential components: a high-voltage power supply, a low-impedance coaxial transmission line with a gap switch, a coaxial oil condenser of 0.2 (mu) F, a turbo-molecular pump, a Krytron pulser as a trigger device, and a flash x-ray tube. The high-voltage main condenser of 0.2 (mu) F was charged from 40 to 60 kV by the power supply, and the electric charges in the condenser were discharged to the tube after closing the gap switch. Because this tube employed a long target, the plasma x-ray source which consists of molybdenum ions and electrons was easily produced by the target evaporating. The maximum tube voltage was nearly equivalent to the initial charge voltage of the main condenser, and the maximum current had a value of about 25 kA with a charging voltage of 60 kV. The average width of flash x rays was less than 1 microsecond(s) , and the time-integrated x-ray intensity with a charging voltage of 60 kV was approximately 20 (mu) C/kg at 1.0 m per pulse. The characteristic K-series intensity substantially increased according to increases in the charged voltage. High-speed dental radiography was performed using a laser timing switch and a trigger-delay device.

  15. NEO Targets for Biological In Situ Resource Utilization

    NASA Astrophysics Data System (ADS)

    Grace, J. M.; Ernst, S. M.; Navarrete, J. U.; Gentry, D.

    2014-12-01

    We are investigating a mission architecture concept for low-cost pre-processing of materials on long synodic period asteroids using bioengineered microbes delivered by small spacecraft. Space exploration opportunities, particularly those requiring a human presence, are sharply constrained by the high cost of launching resources such as fuel, construction materials, oxygen, water, and foodstuffs. Near-Earth asteroids (NEAs) have been proposed for supporting a human space presence. However, the combination of high initial investment requirements, delayed potential return, and uncertainty in resource payoff currently prevents their effective utilization.Biomining is the process in which microorganisms perform useful material reduction, sequestration or separation. It is commonly used in terrestrial copper extraction. Compared to physical and chemical methods of extraction it is slow, but very low cost, thus rendering economical even very poor ores. These advantages are potentially extensible to asteroid in situ resource utilization (ISRU).One of the first limiting factors for the use of biology in these environments is temperature. A survey of NEA data was conducted to identify those NEAs whose projected interior temperatures remained within both potential (-5 - 100 ºC) and preferred (15 - 45 ºC) ranges for the minimum projected time per synodic period without exceeding 100 ºC at any point. Approximately 2800 of the 11000 NEAs (25%) are predicted to remain within the potential range for at least 90 days, and 120 (1%) in the preferred range.A second major factor is water availability and stability. We have evaluated a design for a small-spacecraft-based injector which forces low-temperature fluid into the NEA interior, creating potentially habitable microniches. The fluid contains microbes genetically engineered to accelerate the degradation rates of a desired fraction of the native resources, allowing for more efficient material extraction upon a subsequent

  16. Novel gas-dynamic levitation scheme for noncontact coating of spherical ICF targets

    SciTech Connect

    Kim, K.; Feng, Q.

    1995-12-01

    A novel gas-dynamic levitation technique has been developed to facilitate noncontact coating of spherical ICF targets. Using this technique three metal balls 450 {mu}m, 650 {mu}m and 950 {mu}m in diameter were levitated very stably for several hours, with the balls rotating continuously. Unlike the conventional gas-dynamic levitation scheme in which a single gas-emitting fixture, placed below an object, lifts it up and contains it in a confined volume, the present scheme relies on two fixtures, one placed under and the other above the object. The bottom fixture, as is with the conventional scheme, is a gas emitter; however, the top one is a gas collector shaping the flow field around the object so as to confine the object near the axis of symmetry of the levitation system. As a result, the present system exhibits excellent stability and robustness, and is immune to such external disturbances as nonuniform temperature fields and air currents, and small changes in the levitation gas pressure. The apparatus is inexpensive to fabricate and simple to operate. The details of the apparatus and the preliminary data demonstrating the capability of the levitation scheme are presented. A target coating method, compatible with the present target levitation scheme and suitable for uniform coating of ICF targets, is indicated. 6 refs., 5 figs.

  17. Graphene-coated meshes for electroactive flow control devices utilizing two antagonistic functions of repellency and permeability

    PubMed Central

    Tabassian, Rassoul; Oh, Jung-Hwan; Kim, Sooyeun; Kim, Donggyu; Ryu, Seunghwa; Cho, Seung-Min; Koratkar, Nikhil; Oh, Il-Kwon

    2016-01-01

    The wettability of graphene on various substrates has been intensively investigated for practical applications including surgical and medical tools, textiles, water harvesting, self-cleaning, oil spill removal and microfluidic devices. However, most previous studies have been limited to investigating the intrinsic and passive wettability of graphene and graphene hybrid composites. Here, we report the electrowetting of graphene-coated metal meshes for use as electroactive flow control devices, utilizing two antagonistic functions, hydrophobic repellency versus liquid permeability. Graphene coating was able to prevent the thermal oxidation and corrosion problems that plague unprotected metal meshes, while also maintaining its hydrophobicity. The shapes of liquid droplets and the degree of water penetration through the graphene-coated meshes were controlled by electrical stimuli based on the functional control of hydrophobic repellency and liquid permeability. Furthermore, using the graphene-coated metal meshes, we developed two active flow devices demonstrating the dynamic locomotion of water droplets and electroactive flow switching. PMID:27796291

  18. Graphene-coated meshes for electroactive flow control devices utilizing two antagonistic functions of repellency and permeability

    NASA Astrophysics Data System (ADS)

    Tabassian, Rassoul; Oh, Jung-Hwan; Kim, Sooyeun; Kim, Donggyu; Ryu, Seunghwa; Cho, Seung-Min; Koratkar, Nikhil; Oh, Il-Kwon

    2016-10-01

    The wettability of graphene on various substrates has been intensively investigated for practical applications including surgical and medical tools, textiles, water harvesting, self-cleaning, oil spill removal and microfluidic devices. However, most previous studies have been limited to investigating the intrinsic and passive wettability of graphene and graphene hybrid composites. Here, we report the electrowetting of graphene-coated metal meshes for use as electroactive flow control devices, utilizing two antagonistic functions, hydrophobic repellency versus liquid permeability. Graphene coating was able to prevent the thermal oxidation and corrosion problems that plague unprotected metal meshes, while also maintaining its hydrophobicity. The shapes of liquid droplets and the degree of water penetration through the graphene-coated meshes were controlled by electrical stimuli based on the functional control of hydrophobic repellency and liquid permeability. Furthermore, using the graphene-coated metal meshes, we developed two active flow devices demonstrating the dynamic locomotion of water droplets and electroactive flow switching.

  19. Graphene-coated meshes for electroactive flow control devices utilizing two antagonistic functions of repellency and permeability.

    PubMed

    Tabassian, Rassoul; Oh, Jung-Hwan; Kim, Sooyeun; Kim, Donggyu; Ryu, Seunghwa; Cho, Seung-Min; Koratkar, Nikhil; Oh, Il-Kwon

    2016-10-31

    The wettability of graphene on various substrates has been intensively investigated for practical applications including surgical and medical tools, textiles, water harvesting, self-cleaning, oil spill removal and microfluidic devices. However, most previous studies have been limited to investigating the intrinsic and passive wettability of graphene and graphene hybrid composites. Here, we report the electrowetting of graphene-coated metal meshes for use as electroactive flow control devices, utilizing two antagonistic functions, hydrophobic repellency versus liquid permeability. Graphene coating was able to prevent the thermal oxidation and corrosion problems that plague unprotected metal meshes, while also maintaining its hydrophobicity. The shapes of liquid droplets and the degree of water penetration through the graphene-coated meshes were controlled by electrical stimuli based on the functional control of hydrophobic repellency and liquid permeability. Furthermore, using the graphene-coated metal meshes, we developed two active flow devices demonstrating the dynamic locomotion of water droplets and electroactive flow switching.

  20. Improved tensile and buckling behavior of defected carbon nanotubes utilizing boron nitride coating - A molecular dynamic study

    NASA Astrophysics Data System (ADS)

    Badjian, H.; Setoodeh, A. R.

    2017-02-01

    Synthesizing inorganic nanostructures such as boron nitride nanotubes (BNNTs) have led to immense studies due to their many interesting functional features such as piezoelectricity, high temperature resistance to oxygen, electrical insulation, high thermal conductivity and very long lengths as physical features. In order to utilize the superior properties of pristine and defected carbon nanotubes (CNTs), a hybrid nanotube is proposed in this study by forming BNNTs surface coating on the CNTs. The benefits of such coating on the tensile and buckling behavior of single-walled CNTs (SWCNTs) are illustrated through molecular dynamics (MD) simulations of the resulted nanostructures during the deformation. The AIREBO and Tersoff-Brenner potentials are employed to model the interatomic forces between the carbon and boron nitride atoms, respectively. The effects of chiral indices, aspect ratio, presence of mono-vacancy defects and coating dimension on coated/non-coated CNTs are examined. It is demonstrated that the coated defective CNTs exhibit remarkably enhanced ultimate strength, buckling load capacity and Young's modulus. The proposed coating not only enhances the mechanical properties of the resulted nanostructure, but also conceals it from few external factors impacting the behavior of the CNT such as humidity and high temperature.

  1. Enhancing the utility of existing antibiotics by targeting bacterial behaviour?

    PubMed Central

    Rogers, Geraint B; Carroll, Mary P; Bruce, Kenneth D

    2012-01-01

    The discovery of novel classes of antibiotics has slowed dramatically. This has occurred during a time when the appearance of resistant strains of bacteria has shown a substantial increase. Concern is therefore mounting over our ability to continue to treat infections in an effective manner using the antibiotics that are currently available. While ongoing efforts to discover new antibiotics are important, these must be coupled with strategies that aim to maintain as far as possible the spectrum of activity of existing antibiotics. In many instances, the resistance to antibiotics exhibited by bacteria in chronic infections is mediated not by direct resistance mechanisms, but by the adoption of modes of growth that confer reduced susceptibility. These include the formation of biofilms and the occurrence of subpopulations of ‘persister’ cells. As our understanding of these processes has increased, a number of new potential drug targets have been revealed. Here, advances in our ability to disrupt these systems that confer reduced susceptibility, and in turn increase the efficacy of antibiotic therapy, are discussed. PMID:21864314

  2. 48 CFR 952.226-71 - Utilization of Energy Policy Act target entities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Utilization of Energy... DEPARTMENT OF ENERGY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 952.226-71 Utilization of Energy Policy Act target entities. As prescribed in 926.7007(b),...

  3. 48 CFR 952.226-71 - Utilization of Energy Policy Act target entities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Utilization of Energy... DEPARTMENT OF ENERGY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 952.226-71 Utilization of Energy Policy Act target entities. As prescribed in 926.7007(b),...

  4. 48 CFR 952.226-71 - Utilization of Energy Policy Act target entities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Utilization of Energy... DEPARTMENT OF ENERGY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 952.226-71 Utilization of Energy Policy Act target entities. As prescribed in 926.7007(b),...

  5. 48 CFR 952.226-71 - Utilization of Energy Policy Act target entities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the following clause: Utilization of Energy Policy Act Target Entities (JUN 1996) (a) Definition... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Utilization of Energy... DEPARTMENT OF ENERGY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and...

  6. 48 CFR 952.226-71 - Utilization of Energy Policy Act target entities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Utilization of Energy... DEPARTMENT OF ENERGY CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 952.226-71 Utilization of Energy Policy Act target entities. As prescribed in 926.7007(b), insert...

  7. Systems and methods for coating conduit interior surfaces utilizing a thermal spray gun with extension arm

    DOEpatents

    Moore, Karen A.; Zatorski, Raymond A.

    2005-07-12

    Systems and methods for applying a coating to an interior surface of a conduit. In one embodiment, a spray gun configured to apply a coating is attached to an extension arm which may be inserted into the bore of a pipe. The spray gun may be a thermal spray gun adapted to apply a powder coating. An evacuation system may be used to provide a volume area of reduced air pressure for drawing overspray out of the pipe interior during coating. The extension arm as well as the spray gun may be cooled to maintain a consistent temperature in the system, allowing for more consistent coating.

  8. Methods for coating conduit interior surfaces utilizing a thermal spray gun with extension arm

    DOEpatents

    Moore, Karen A.; Zatorski, Raymond A.

    2007-10-02

    Systems and methods for applying a coating to an interior surface of a conduit. In one embodiment, a spray gun configured to apply a coating is attached to an extension arm which may be inserted into the bore of a pipe. The spray gun may be a thermal spray gun adapted to apply a powder coating. An evacuation system may be used to provide a volume area of reduced air pressure for drawing overspray out of the pipe interior during coating. The extension arm as well as the spray gun may be cooled to maintain a consistent temperature in the system, allowing for more consistent coating.

  9. High paclitaxel-loaded and tumor cell-targeting hyaluronan-coated nanoemulsions.

    PubMed

    Kim, Joo-Eun; Park, Young-Joon

    2017-02-01

    The purpose of this study was to develop hyaluronan-coated nanoemulsions (HNEs) with high solubilizing capacity and tumor cell targeting capability for the poorly soluble paclitaxel. The HNEs were composed of dl-a-tocopheryl acetate, soybean oil, polysorbate 80, and ferric chloride and were coated with hyaluronic acid (HA) as a targeting moiety. The nanoemulsions (NEs) and HNEs with or without paclitaxel (PTX) were prepared using high-pressure homogenization with a microfluidizer and were lyophilized with d-mannitol. The particle diameter and zeta potential of the HNEs were 65±15nm and -39.5±0.33mV, respectively. The concentration of PTX loaded in the NEs was 6mg/mL, which was higher than that in any other nanocarrier. The HNEs were coated with HA on the outer surface of the sphere and the amount of HA was 0.82±0.10% (w/w). The lyophilized formulation was stable at 4°C for 12 months and the reconstituted HNE solution was stable for at least 96h, even though Taxol(®) can be maintained for only 72h. In the cell affinity studies with SK-OV-3 (cluster of differentiation 44 [CD44](+)) and OVCAR-3 (CD44(-)) cells, the HNEs displayed a 10-fold higher targeting capability than the NEs did. Therefore, the HNEs displayed high drug loading capability, excellent stability, and targeting of tumor cells overexpressing CD44, which suggested they were a potentially effective nanocarrier for carrying poorly soluble paclitaxel and targeting tumors. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Repair of Damaged M-Chromium-Aluminum-Yttrium Coatings Targeting Petroleum Industry Applications

    NASA Astrophysics Data System (ADS)

    Farhat, Rabab

    The increase in efficiency of furnace and refinery components in petroleum industries has been the target of many studies. However, the repair technology for damaged pieces is still to be developed. During prolonged service, a degradation of developed coatings occurs as a result of the harsh environment. Therefore, a repair technology, which can extend the life of the coatings, is now under consideration. In this work, electrospark deposition (ESD) has been investigated to understand the solidification behavior and its possibility to repair damaged MCrAlY coatings. Ni-based alloys with different compositions were deposited on Ni substrate using ESD to understand crystal structure of the solidified deposit and the effect of the dissimilar weld composition on dilution. The electrode samples were prepared by spark plasma sintering (SPS). Firstly, different coatings with single and bi-phase microstructure were deposited on pure Ni substrate. Secondly, NiCoCrAlY and CoNiCrAlY were deposited on the damaged spot of the oxidized NiCoCrAlY and CoNiCrAlY respectively. A fine microstructure of metastable phases obtained from each deposit. Also, it was found that an epitaxial growth of NiCoCrAlY and CoNiCrAlY were obtained on the damaged spots. In addition, α-Al 2O3 was obtained on the surface of the deposit after 24hr oxidation at 1000°C.

  11. Low pH impairs complement-dependent cytotoxicity against IgG-coated target cells

    PubMed Central

    Dantas, Ezequiel; Díaz, Fernando Erra; Gerber, Pehuén Pereyra; Merlotti, Antonela; Varese, Augusto; Ostrowski, Matías; Sabatté, Juan; Geffner, Jorge

    2016-01-01

    Local acidosis is a common feature of allergic, vascular, autoimmune, and cancer diseases. However, few studies have addressed the effect of extracellular pH on the immune response. Here, we analyzed whether low pH could modulate complement-dependent cytotoxicity (CDC) against IgG-coated cells. Using human serum as a complement source, we found that extracellular pH values of 5.5 and 6.0 strongly inhibit CDC against either B lymphoblast cell lines coated with the chimeric anti-CD20 mAb rituximab or PBMCs coated with the humanized anti-CD52 mAb alemtuzumab. Suppression of CDC by low pH was observed either in cells suspended in culture medium or in whole blood assays. Interestingly, not only CDC against IgG-coated cells, but also the activation of the complement system induced by the alternative and lectin pathways was prevented by low pH. Tumor-targeting mAbs represent one of the most successful tools for cancer therapy, however, the use of mAb monotherapy has only modest effects on solid tumors. Our present results suggest that severe acidosis, a hallmark of solid tumors, might impair complement-mediated tumor destruction directed by mAb. PMID:27716623

  12. Human lymph node lymphocytes fail to effect lysis of antibody-coated target cells.

    PubMed Central

    O'Toole, C; Saxon, A; Bohrer, R

    1977-01-01

    Human lymphocytes prepared from peripheral blood, lymph nodes, spleen and thymus were titrated for ability to mediate lysis of human target cells coated with rabbit anti target antibody. Lymphocytes from blood and spleen produced efficient lysis of targets in the presence of antibody. Lymph node cells and thymocytes were essentially non-reactive in this system. Lymph node preparations from non-cancer patients contained approximately 25% of non-T cells with receptors for Fc,C3 and/or Ig. Regional lymph nodes from patients with primary tumours contained 37-50% non-T cells by the same criteria. Failure of lymph node lymphocytes to effect lysis of antibody-coated targets did not therefore correlate with content of Fc or C3 bearing cells per se. The effector cell in antibody-dependent cytotoxicity in other systems has been shown to carry Fc and C3 receptors, but not surface Ig. This cell type appears to be absent or non-functional in human lymph nodes. PMID:300304

  13. Characterization of ethylcellulose: starch-based film coatings for colon targeting.

    PubMed

    Karrout, Youness; Neut, Christel; Wils, Daniel; Siepmann, Florence; Deremaux, Laetitia; Desreumaux, Pierre; Siepmann, Juergen

    2009-10-01

    The site-specific delivery of drugs to the colon can be highly advantageous for various applications, including the local treatment of inflammatory bowel diseases. The aim of this study was to provide efficient tools that can be used to easily adjust the key properties of novel polymeric film coatings allowing for colon targeting. Free films based on blends of ethylcellulose and different types of starch derivatives (partially being pregelatinized, acetylated, and/or hydroxypropylated) were prepared and characterized. The key properties of the polymeric systems can effectively be adjusted by varying the polymer blend ratio and type of starch derivative. This includes the water uptake and dry mass loss kinetics as well as the mechanical properties of the films before and upon exposure to aqueous media simulating the contents of the upper GIT. Broad ranges of film coating properties can easily be provided, being adapted to the needs of the respective drug treatment.

  14. Compression of polymer-coated laser-fusion targets to ten times liquid DT density

    SciTech Connect

    Auerbach, J.M.; Mead, W.C.; Campbell, E.M.; Matthews, D.L.; Bailey, D.S.; Hatcher, C.W.; Koppel, L.N.; Lane, S.M.; Lee, P.H.Y.; Manes, K.R.; McClellan, G.; Phillion, D.W.; Price, R.H.; Rupert, V.C.; Slivinsky, V.W.; Swift, C.D.

    1980-06-23

    Polymer-coated glass microspheres filled with DT fuel and argon seed gas were irradiated on the SHIVA 1.06-..mu..m laser using 4-kJ 200 ps (full width at half maximum), Gaussian pulses. Measured light absorption, x-ray spectrum, neutron yields, and x-ray continuum images compare favorably with detailed computer simulations. Pusher neutron activation and argon line imaging diagnostics were utilized to measure fuel density. Fuel densities of 1-3 g/cm/sup 3/ or 5-15 times liquid DT density were inferred.

  15. Casein-coated iron oxide nanoparticles for high MRI contrast enhancement and efficient cell targeting.

    PubMed

    Huang, Jing; Wang, Liya; Lin, Run; Wang, Andrew Y; Yang, Lily; Kuang, Min; Qian, Weiping; Mao, Hui

    2013-06-12

    Surface properties, as well as inherent physicochemical properties, of the engineered nanomaterials play important roles in their interactions with the biological systems, which eventually affect their efficiency in diagnostic and therapeutic applications. Here we report a new class of MRI contrast agent based on milk casein protein-coated iron oxide nanoparticles (CNIOs) with a core size of 15 nm and hydrodynamic diameter ~30 nm. These CNIOs exhibited excellent water-solubility, colloidal stability, and biocompatibility. Importantly, CNIOs exhibited prominent T2 enhancing capability with a transverse relaxivity r2 of 273 mM(-1) s(-1) at 3 tesla. The transverse relaxivity is ~2.5-fold higher than that of iron oxide nanoparticles with the same core but an amphiphilic polymer coating. CNIOs showed pH-responsive properties, formed loose and soluble aggregates near the pI (pH ~4.0). The aggregates could be dissociated reversibly when the solution pH was adjusted away from the pI. The transverse relaxation property and MRI contrast enhancing effect of CNIOs remained unchanged in the pH range of 2.0-8.0. Further functionalization of CNIOs can be achieved via surface modification of the protein coating. Bioaffinitive ligands, such as a single chain fragment from the antibody of epidermal growth factor receptor (ScFvEGFR), could be readily conjugated onto the protein coating, enabling specific targeting to MDA-MB-231 breast cancer cells overexpressing EGFR. T2-weighted MRI of mice intravenously administered with CNIOs demonstrated strong contrast enhancement in the liver and spleen. These favorable properties suggest CNIOs as a class of biomarker targeted magnetic nanoparticles for MRI contrast enhancement and related biomedical applications.

  16. Targeting N-acetylglucosamine-bearing polymer-coated liposomes to vascular smooth muscle cells.

    PubMed

    Ise, Mamiko; Ise, Hirohiko; Shiba, Yuji; Kobayashi, Satoshi; Goto, Mitsuaki; Takahashi, Masafumi; Akaike, Toshihiro; Ikeda, Uichi

    2011-12-01

    The targeted delivery of anti-inflammatory agents has great therapeutic potential for treating restenosis following percutaneous coronary intervention. To develop a drug delivery system targeted to injured blood vessels, we examined whether N-acetylglucosamine (GlcNAc)-bearing polymer-coated liposomes (GlcNAc-Ls) are specifically taken up by vascular smooth muscle cells (VSMCs). Flow cytometric analysis revealed that GlcNAc-Ls were taken up by VSMCs in vitro. Furthermore, GlcNAc-Ls were intravenously administered to mice that had undergone wire-mediated vascular injury. GlcNAc-Ls markedly accumulated at the intramural site of the injured vessel walls but not at the contralateral (uninjured) vessel walls. These results demonstrated that GlcNAc-Ls can be specifically taken up by VSMCs both in vitro and in vivo. We propose a novel strategy of using GlcNAc-Ls that has potential for application in drug delivery targeted to injured blood vessels.

  17. An inexpensive and fast method for infiltration coating of complex geometry matrices for ISOL production target applications

    NASA Astrophysics Data System (ADS)

    Kawai, Y.; Alton, G. D.; Bilheux, J.-C.

    2005-12-01

    An inexpensive, fast, and close to universal infiltration coating technique has been developed for fabricating fast diffusion-release ISOL targets. Targets are fabricated by deposition of finely divided (∼1 μm) compound materials in a paint-slurry onto highly permeable, complex structure reticulated-vitreous-carbon-foam (RVCF) matrices, followed by thermal heat treatment. In this article, we describe the coating method and present information on the physical integrity, uniformity of deposition, and matrix adherence of SiC, HfC and UC2 targets, destined for on-line use as targets at the Holifield Radioactive Ion Beam Facility (HRIBF).

  18. Modeling the absorption behavior of solar thermal collector coatings utilizing graded alpha-C:H/TiC layers.

    PubMed

    Gruber, D P; Engel, G; Sormann, H; Schüler, A; Papousek, W

    2009-03-10

    Wavelength selective coatings are of common use in order to enhance the efficiency of devices heated by radiation such as solar thermal collectors. The use of suitable materials and the optimization of coating layer thicknesses are advisable ways to maximize the absorption. Further improvement is achievable by embedding particles in certain layers in order to modify material properties. We focus on optimizing the absorption behavior of a solar collector setup using copper as substrate, a layer of amorphous hydrogenated carbon with embedded titanium carbide particles (a-C:H/TiC), and an antireflection coating of amorphous silicon dioxide (aSiO(2)). For the setup utilizing homogeneous particle distribution, a relative absorption of 90.98% was found, while inhomogeneous particle embedding yielded 98.29%. These results are particularly interesting since until now, absorption of more than 95% was found only by using embedded Cr but not by using the more biocompatible Ti.

  19. Qualification of Target Chamber Vacuum Systems Cleanliness using Sol-Gel Coatings

    SciTech Connect

    Miller, P; Stowers, I F; Ertel, J R

    2006-01-03

    This document defines the procedure necessary to qualify the airborne molecular cleanliness (AMC) of vacuum systems (enclosures or large components) that are placed within the National Ignition Facility (NIF) target chamber or are attached to it and communicate with it during vacuum operation. This test is specific to the NIF target chamber because the allowable time dependent rate of rise in the pore filling of a sol-gel coated SAW sensor is based on some nominal change-out time for the disposable debris shields. These debris shields will be sol-gel coated and thus they represent a means of ''pumping'' AMCs from the target chamber. The debris shield pumping rate sets the allowable change in pore filling with time specified in the test procedure. This document describes a two-part procedure that provides both a static measurement of sol-gel pore filling at the end of a 48-hour test period and a dynamic record of pore-filling measured throughout the test period. Successful qualification of a vacuum system requires that both the static and dynamic measurements meet the criteria set forth in Section 7 of this document.

  20. Suppression of atopic dermatitis in mice model by reducing inflammation utilizing phosphatidylserine-coated biodegradable microparticles.

    PubMed

    Kumar, Purnima; Hosain, Md Zahangir; Kang, Jeong-Hun; Takeo, Masafumi; Kishimura, Akihiro; Mori, Takeshi; Katayama, Yoshiki

    2015-01-01

    Controlling inflammatory response is important to avoid chronic inflammation in many diseases including atopic dermatitis (AD). In this research, we tried using a phosphatidylserine (PS)-coated microparticles in the AD mouse model for achieving the modulation of the macrophage phenotype to an anti-inflammatory state. Here, we prepared poly (D,L-lactic acid) microparticle coated with PS on the outside shell. We confirmed the cellular uptake of the PS-coated microparticle, which leads to the significant downregulation of the inflammatory cytokine production. In the mouse model of AD, the PS-coated microparticle was injected subcutaneously for a period of 12 days. The mice showed significant reduction in the development of AD symptoms comparing with the mice treated with the PC-coated microparticle.

  1. New pricing approaches for bundled payments: Leveraging clinical standards and regional variations to target avoidable utilization.

    PubMed

    Hellsten, Erik; Chu, Scally; Crump, R Trafford; Yu, Kevin; Sutherland, Jason M

    2016-03-01

    Develop pricing models for bundled payments that draw inputs from clinician-defined best practice standards and benchmarks set from regional variations in utilization. Health care utilization and claims data for a cohort of incident Ontario ischemic and hemorrhagic stroke episodes. Episodes of care are created by linking incident stroke hospitalizations with subsequent health service utilization across multiple datasets. Costs are estimated for episodes of care and constituent service components using setting-specific case mix methodologies and provincial fee schedules. Costs are estimated for five areas of potentially avoidable utilization, derived from best practice standards set by an expert panel of stroke clinicians. Alternative approaches for setting normative prices for stroke episodes are developed using measures of potentially avoidable utilization and benchmarks established by the best performing regions. There are wide regional variations in the utilization of different health services within episodes of stroke care. Reconciling the best practice standards with regional utilization identifies significant amounts of potentially avoidable utilization. Normative pricing models for stroke episodes result in increasingly aggressive redistributions of funding. Bundled payment pilots to date have been based on the costs of historical service patterns, which effectively 'bake in' unwarranted and inefficient variations in utilization. This study demonstrates the feasibility of novel clinically informed episode pricing approaches that leverage these variations to target reductions in potentially avoidable utilization. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Modular Fabrication of Polymer Brush Coated Magnetic Nanoparticles: Engineering the Interface for Targeted Cellular Imaging.

    PubMed

    Oz, Yavuz; Arslan, Mehmet; Gevrek, Tugce N; Sanyal, Rana; Sanyal, Amitav

    2016-08-03

    Development of efficient and rapid protocols for diversification of functional magnetic nanoparticles (MNPs) would enable identification of promising candidates using high-throughput protocols for applications such as diagnostics and cure through early detection and localized delivery. Polymer brush coated magnetic nanoparticles find use in many such applications. A protocol that allows modular diversification of a pool of parent polymer coated nanoparticles will lead to a library of functional materials with improved uniformity. In the present study, polymer brush coated parent magnetic nanoparticles obtained using reversible addition-fragmentation chain transfer (RAFT) polymerization are modified to obtain nanoparticles with different "clickable" groups. In this design, trithiocarbonate group terminated polymer brushes are "grafted from" MNPs using a catechol group bearing initiator. A postpolymerization radical exchange reaction allows installation of "clickable" functional groups like azides and maleimides on the chain ends of the polymers. Thus, modified MNPs can be functionalized using alkyne-containing and thiol-containing moieties like peptides and dyes using the alkyne-azide cycloaddition and the thiol-ene conjugation, respectively. Using the approach outlined here, a cell surface receptor targeting cyclic peptide and a fluorescent dye are attached onto nanoparticle surface. This multifunctional construct allows selective recognition of cancer cells that overexpress integrin receptors. Furthermore, the approach outlined here is not limited to the installation of azide and maleimide functional groups but can be expanded to a variety of "clickable" groups to allow nanoparticle modification using a broad range of chemical conjugations.

  3. Tumor targeting profiling of hyaluronan-coated lipid based-nanoparticles

    NASA Astrophysics Data System (ADS)

    Mizrahy, Shoshy; Goldsmith, Meir; Leviatan-Ben-Arye, Shani; Kisin-Finfer, Einat; Redy, Orit; Srinivasan, Srimeenakshi; Shabat, Doron; Godin, Biana; Peer, Dan

    2014-03-01

    Hyaluronan (HA), a naturally occurring high Mw (HMw) glycosaminoglycan, has been shown to play crucial roles in cell growth, embryonic development, healing processes, inflammation, and tumor development and progression. Low Mw (LMw, <10 kDa) HA has been reported to provoke inflammatory responses, such as induction of cytokines, chemokines, reactive nitrogen species and growth factors. Herein, we prepared and characterized two types of HA coated (LMw and HMw) lipid-based targeted and stabilized nanoparticles (tsNPs) and tested their binding to tumor cells expressing the HA receptor (CD44), systemic immunotoxicity, and biodistribution in tumor bearing mice. In vitro, the Mw of the surface anchored HA had a significant influence on the affinity towards CD44 on B16F10 murine melanoma cells. LMw HA-tsNPs exhibited weak binding, while binding of tsNPs coated with HMw HA was characterized by high binding. Both types of tsNPs had no measured effect on cytokine induction in vivo following intravenous administration to healthy C57BL/6 mice suggesting no immune activation. HMw HA-tsNPs showed enhanced circulation time and tumor targeting specificity, mainly by accumulating in the tumor and its vicinity compared with LMw HA-tsNPs. Finally, we show that methotrexate (MTX), a drug commonly used in cancer chemotherapy, entrapped in HMw HA-tsNPs slowly diffused from the particles with a half-life of 13.75 days, and improved the therapeutic outcome in a murine B16F10 melanoma model compared with NPs suggesting an active cellular targeting beyond the Enhanced Permeability and Retention (EPR) effect. Taken together, these findings have major implications for the use of high molecular weight HA in nanomedicine as a selective and safe active cellular targeting moiety.Hyaluronan (HA), a naturally occurring high Mw (HMw) glycosaminoglycan, has been shown to play crucial roles in cell growth, embryonic development, healing processes, inflammation, and tumor development and progression

  4. Sol-gel coatings for high pressure polarized ^3He nuclear targets

    NASA Astrophysics Data System (ADS)

    Deur, Alexandre; Cates, Gordon D.; Chaput, Julien; Singh, Jaideep; Tobias, William A.

    2001-11-01

    Sol-gel coated glass cells have been shown to exhibit longitudinal lifetimes T1 in excess of 350 hours for ^3He that is polarized by spin-exchange optical pumping.( Ming F. Hsu shape et al, Appl. Phys. Lett.) series 77 (2000) 2069. The sol-gel technique was designed to minimize spin-relaxation due to wall collisions so that only dipole-dipole interactions between colliding ^3He atoms dominate in the relaxation process. Until now, sol-gel technology has not been applied to high pressure ^3He gas targets used in nuclear scattering experiments. Latest developments on incorporating the sol-gel technique in the production of these ^3He targets will be presented.

  5. A novel coating concept for ileo-colonic drug targeting: proof of concept in humans using scintigraphy.

    PubMed

    Varum, F J O; Hatton, G B; Freire, A C; Basit, A W

    2013-08-01

    The in vivo proof of concept of a novel double-coating system, based on enteric polymers, which accelerated drug release in the ileo-colonic region, was investigated in humans. Prednisolone tablets were coated with a double-coating formulation by applying an inner layer composed of EUDRAGIT S neutralised to pH 8.0 and a buffer salt (10% KH₂PO₄), which was overcoated with layer of standard EUDRAGIT S organic solution. For comparison, a single coating system was produced by applying the same amount of EUDRAGIT S organic solution on the tablet cores. Dissolution tests on the tablets were carried out using USP II apparatus in 0.1N HCl for 2 h and subsequently in pH 7.4 Krebs bicarbonate buffer. For comparison, tablets were also tested under the USP method established for modified release mesalamine formulations. Ten fasted volunteers received the double-coated and single-coated tablets in a two-way crossover study. The formulations were radiolabelled and followed by gamma scintigraphy; the disintegration times and positions were recorded. There was no drug release from the single-coated or double-coated tablets in 0.1N HCl for 2h. The single-coated tablets showed slow release in subsequent Krebs bicarbonate buffer with a lag time of 120 min, while in contrast drug release from the double-coated tablets was initiated at 60 min. In contrast, using the USP dissolution method, normally employed for modified release mesalamine products, no discrimination was attained. The in vivo disintegration of the single-coated EUDRAGIT S tablets in the large intestine was erratic. Furthermore, in 2 volunteers, the single-coated tablet was voided intact. Double-coated tablets disintegrated in a more consistent way, mainly in the ileo-caecal junction or terminal ileum. The accelerated in vivo disintegration of the double-coating EUDRAGIT S system can overcome the limitations of conventional enteric coatings targeting the colon and avoid the pass-through of intact tablets. Moreover

  6. Materials and Coatings for Extreme Performances: Investigations, Applications, Ecologically Safe Technologies for Their Production and Utilization

    DTIC Science & Technology

    2004-11-16

    Of practical interest for producing nanocoatings by using initial nanocrystalline powders is detonation (DS), plasma (PS) and HVOF spraying...technologies help to preserve the nanocrystalline structure in a finished coating. The decisive factor that ensures high properties of nanocoatings

  7. Targeted gold-coated iron oxide nanoparticles for CD163 detection in atherosclerosis by MRI

    PubMed Central

    Tarin, Carlos; Carril, Monica; Martin-Ventura, Jose Luis; Markuerkiaga, Irati; Padro, Daniel; Llamas-Granda, Patricia; Moreno, Juan Antonio; García, Isabel; Genicio, Nuria; Plaza-Garcia, Sandra; Blanco-Colio, Luis Miguel; Penades, Soledad; Egido, Jesus

    2015-01-01

    CD163 is a membrane receptor expressed by macrophage lineage. Studies performed in atherosclerosis have shown that CD163 expression is increased at inflammatory sites, pointing at the presence of intraplaque hemorrhagic sites or asymptomatic plaques. Hence, imaging of CD163 expressing macrophages is an interesting strategy in order to detect atherosclerotic plaques. We have prepared a targeted probe based on gold-coated iron oxide nanoparticles vectorized with an anti-CD163 antibody for the specific detection of CD163 by MRI. Firstly, the specificity of the targeted probe was validated in vitro by incubation of the probe with CD163(+) or (−) macrophages. The probe was able to selectively detect CD163(+) macrophages both in human and murine cells. Subsequently, the targeted probe was injected in 16 weeks old apoE deficient mice developing atherosclerotic lesions and the pararenal abdominal aorta was imaged by MRI. The accumulation of probe in the site of interest increased over time and the signal intensity decreased significantly 48 hours after the injection. Hence, we have developed a highly sensitive targeted probe capable of detecting CD163-expressing macrophages that could provide useful information about the state of the atheromatous lesions. PMID:26616677

  8. Targeted gold-coated iron oxide nanoparticles for CD163 detection in atherosclerosis by MRI.

    PubMed

    Tarin, Carlos; Carril, Monica; Martin-Ventura, Jose Luis; Markuerkiaga, Irati; Padro, Daniel; Llamas-Granda, Patricia; Moreno, Juan Antonio; García, Isabel; Genicio, Nuria; Plaza-Garcia, Sandra; Blanco-Colio, Luis Miguel; Penades, Soledad; Egido, Jesus

    2015-11-30

    CD163 is a membrane receptor expressed by macrophage lineage. Studies performed in atherosclerosis have shown that CD163 expression is increased at inflammatory sites, pointing at the presence of intraplaque hemorrhagic sites or asymptomatic plaques. Hence, imaging of CD163 expressing macrophages is an interesting strategy in order to detect atherosclerotic plaques. We have prepared a targeted probe based on gold-coated iron oxide nanoparticles vectorized with an anti-CD163 antibody for the specific detection of CD163 by MRI. Firstly, the specificity of the targeted probe was validated in vitro by incubation of the probe with CD163(+) or (-) macrophages. The probe was able to selectively detect CD163(+) macrophages both in human and murine cells. Subsequently, the targeted probe was injected in 16 weeks old apoE deficient mice developing atherosclerotic lesions and the pararenal abdominal aorta was imaged by MRI. The accumulation of probe in the site of interest increased over time and the signal intensity decreased significantly 48 hours after the injection. Hence, we have developed a highly sensitive targeted probe capable of detecting CD163-expressing macrophages that could provide useful information about the state of the atheromatous lesions.

  9. Adenoviral vectors coated with PAMAM dendrimer conjugates allow CAR independent virus uptake and targeting to the EGF receptor.

    PubMed

    Vetter, Alexandra; Virdi, Kulpreet S; Espenlaub, Sigrid; Rödl, Wolfgang; Wagner, Ernst; Holm, Per S; Scheu, Christina; Kreppel, Florian; Spitzweg, Christine; Ogris, Manfred

    2013-02-04

    Adenovirus type 5 (Ad) is an efficient gene vector with high gene transduction potential, but its efficiency depends on its native cell receptors coxsackie- and adenovirus receptor (CAR) for cell attachment and α(v)β(3/5) integrins for internalization. To enable transduction of CAR negative cancer cell lines, we have coated the negatively charged Ad by noncovalent charge interaction with cationic PAMAM (polyamidoamine) dendrimers. The specificity for tumor cell infection was increased by targeting the coated Ad to the epidermal growth factor receptor using the peptide ligand GE11, which was coupled to the PAMAM dendrimer via a 2 kDa PEG spacer. Particles were examined by measuring surface charge and size, the degree of coating was determined by transmission electron microscopy. The net positive charge of PAMAM coated Ad enhanced cellular binding and uptake leading to increased transduction efficiency, especially in low to medium CAR expressing cancer cell lines using enhanced green fluorescent protein or luciferase as transgene. While PAMAM coated Ad allowed for efficient internalization, coating with linear polyethylenimine induced excessive particle aggregation, elevated cellular toxicity and lowered transduction efficiency. PAMAM coating of Ad enabled successful transduction of cells in vitro even in the presence of neutralizing antibodies. Taken together, this study clearly proves noncovalent, charge-based coating of Ad vectors with ligand-equipped dendrimers as a viable strategy for efficient transduction of cells otherwise refractory to Ad infection.

  10. Low frequency of target organ damage in Taiwanese with white coat hypertension.

    PubMed

    Tseng, Yung-Zu; Chiang, Fu-Tien; Hsu, Kwan-Lih; Lo, Huey-Ming; Tseng, Chuen-Den; Lin, Jiunn-Lee; Hwang, Juey-Jen; Lai, Ling-Ping

    2005-05-01

    The clinical importance of white coat hypertension (WCH) remains to be clarified. This study investigated the target organ damage in Taiwanese with WCH. A total of 188 consecutive Taiwanese (88 men and 100 women), aged 26 to 75 years who had an abnormal office casual blood pressure (systolic blood pressure >/= 140 mm Hg or diastolic blood pressure >/= 90 mm Hg or both) and a normal ambulatory blood pressure (ABP) average (systolic ABP average < 140 mm Hg and diastolic ABP average < 90 mm Hg) at the outpatient clinic or from a mass survey were enrolled. Office casual blood pressure measurements were obtained by standard sphygmomanometric methods. Twenty-four-hour blood pressures were recorded by a commercial ambulatory pressure recorder (Del Mar Avionics, Model 1990 Pressurometer IV System). Hypertension-related target organ complications were assessed by electrocardiogram, chest X-ray, urinalysis and eye fundus examinations. Target organ damage was found in 6.4% of subjects with WCH. Roentgenographic left ventricular hypertrophy (LVH) was found in 1.1% of subjects and electrocardiographic LVH in 2.7%. Proteinuria was found in 1.6% of subjects and retinopathy in 1.1%. The frequencies of various target organ damage were not significantly associated with age, gender and the definition of normal ABP average as 135/85 mm Hg or 140/90 mm Hg. WCH represents a low-risk stratum for target organ damage in Taiwanese. These subjects should be identified and followed up regularly. The factors responsible for the low frequency of target organ damage in Taiwanese with WCH need further study.

  11. Functionalized milk-protein-coated magnetic nanoparticles for MRI-monitored targeted therapy of pancreatic cancer

    PubMed Central

    Huang, Jing; Qian, Weiping; Wang, Liya; Wu, Hui; Zhou, Hongyu; Wang, Andrew Yongqiang; Chen, Hongbo; Yang, Lily; Mao, Hui

    2016-01-01

    Engineered nanocarriers have emerged as a promising platform for cancer therapy. However, the therapeutic efficacy is limited by low drug loading efficiency, poor passive targeting to tumors, and severe systemic side effects. Herein, we report a new class of nanoconstructs based on milk protein (casein)-coated magnetic iron oxide (CNIO) nanoparticles for targeted and image-guided pancreatic cancer treatment. The tumor-targeting amino-terminal fragment (ATF) of urokinase plasminogen activator and the antitumor drug cisplatin (CDDP) were engineered on this nanoplatform. High drug loading (~25 wt%) and sustained release at physiological conditions were achieved through the exchange and encapsulation strategy. These ATF-CNIO-CDDP nanoparticles demonstrated actively targeted delivery of CDDP to orthotopic pancreatic tumors in mice. The effective accumulation and distribution of ATF-CNIO-CDDP was evidenced by magnetic resonance imaging, based on the T2-weighted contrast resulting from the specific accumulation of ATF-CNIO-CDDP in the tumor. Actively targeted delivery of ATF-CNIO-CDDP led to improved therapeutic efficacy in comparison with free CDDP and nontargeted CNIO-CDDP treatment. Meanwhile, less systemic side effects were observed in the nanocarrier-treated groups than that in the group treated with free CDDP. Hematoxylin and Eosin and Sirius Red staining of tumor sections revealed the possible disruption of stroma during the treatment with ATF-CNIO-CDDP. Overall, our results suggest that ATF-CNIO-CDDP can be an effective theranostic platform for active targeting-enhanced and image-guided cancer treatment while simultaneously reducing the systemic toxicity. PMID:27462153

  12. Testing of glove efficacy against sprayed isocyanate coatings utilizing a reciprocating permeation panel.

    PubMed

    Ceballos, Diana M; Sasakura, Miyoko; Reeb-Whitaker, Carolyn; Broadwater, Kendra; Milbauer, Mark; Crampton, Robert; Dills, Russell; Yost, Michael G

    2014-01-01

    Modify a permeation panel to evaluate dermal protective clothing for resistance to sprayed coatings with minimal variability in spray paint loading across the test panel. Determine isocyanate protection effectiveness of natural rubber latex (5 mil or 0.13mm), nitrile rubber (5 mil or 0.13mm), and butyl rubber (13 mil or 0.33mm) glove materials against a commonly used automotive clear coat formulation. The latex and nitrile gloves were the type used by the local autobody spray painters. Glove materials were tested by spraying paint onto an automated reciprocating permeation panel (permeation panel II). Temperature, relative humidity, and spray conditions were controlled to optimize paint loading homogeneity as evaluated by gravimetric analysis. Isocyanate permeation was measured using 1-(2-pyridyl)-piperazine-coated fiber-glass filters analyzed by a modified version of the OSHA 42/PV2034 methods. Latex exhibited a higher permeation rate compared with nitrile for isocyanates (1,6-hexamethylene diisocyanate (HDI) and isophorone diisocyanate monomers) and both materials presented permeation at all of the time points suggesting a fast isocyanate breakthrough. Butyl material exhibited no permeation or breakthrough for isocyanates under the tested conditions. The spray application at 69±8°F was optimally homogeneous at 45±0.5mg weight of dry clear coat per 5cm(2). The permeation panel II is a reliable method to assess dermal protective clothing performance against polymerizing coatings. Commonly used 5-mil (0.13-mm) latex and nitrile gloves were determined to be ineffective barriers against the isocyanates found in a commonly used clear-coat formulation while butyl gloves were protective.

  13. In Vitro and In Vivo Correlation of Colon-Targeted Compression-Coated Tablets

    PubMed Central

    Kundu, Amit; Karmakar, Sanmoy; Sa, Biswanath

    2016-01-01

    This study was performed to assess and correlate in vitro drug release with in vivo absorption of prednisolone (PDL) from a colon-targeted tablet prepared by compression coating of core tablet. In vivo drug absorption study was conducted using a high performance liquid chromatographic (HPLC) method, which was developed and validated for the estimation of PDL in rabbit plasma. The calibration curve showed linearity in the concentration range of 0.05 to 50 μg/mL with the correlation coefficient (r) of 0.999. The method was specific and sensitive with the limit of detection (LOD) and lower limit of quantification (LLOQ) of 31.89 ± 1.10 ng/mL and 96.63 ± 3.32 ng/mL, respectively. The extraction recovery (ER) of PDL from three different levels of quality control (QC) samples ranged from 98.18% to 103.54%. In vitro drug release study revealed that less than 10% drug was released in 6.34 h and almost complete (98.64%) drug release was achieved in the following 6 h. In vivo drug absorption study demonstrated lower values of Cmax, AUCtotal, and protracted Tmax from compression-coated tablet. The results confirmed the maximum release of drug in the colon while minimizing release in the upper gastrointestinal tract (GIT). An excellent in vitro and in vivo correlation (IVIVC) was also achieved after considering the lag time. PMID:26989562

  14. Pharmaceutical formulation of HSA hybrid coated iron oxide nanoparticles for magnetic drug targeting.

    PubMed

    Zaloga, Jan; Pöttler, Marina; Leitinger, Gerd; Friedrich, Ralf P; Almer, Gunter; Lyer, Stefan; Baum, Eva; Tietze, Rainer; Heimke-Brinck, Ralph; Mangge, Harald; Dörje, Frank; Lee, Geoffrey; Alexiou, Christoph

    2016-04-01

    In this work we present a new formulation of superparamagnetic iron oxide nanoparticles (SPIONs) for magnetic drug targeting. The particles were reproducibly synthesized from current good manufacturing practice (cGMP) - grade substances. They were surface coated using fatty acids as anchoring molecules for human serum albumin. We comprehensively characterized the physicochemical core-shell structure of the particles using sophisticated methods. We investigated biocompatibility and cellular uptake of the particles using an established flow cytometric method in combination with microwave-plasma assisted atomic emission spectroscopy (MP-AES). The cytotoxic drug mitoxantrone was adsorbed on the protein shell and we showed that even in complex media it is slowly released with a close to zero order kinetics. We also describe an in vitro proof-of-concept assay in which we clearly showed that local enrichment of this SPION-drug conjugate with a magnet allows site-specific therapeutic effects.

  15. Refinement of adsorptive coatings for fluorescent riboflavin-receptor-targeted iron oxide nanoparticles.

    PubMed

    Tsvetkova, Yoanna; Beztsinna, Nataliia; Jayapaul, Jabadurai; Weiler, Marek; Arns, Susanne; Shi, Yang; Lammers, Twan; Kiessling, Fabian

    2016-01-01

    Flavin mononucleotide (FMN) is a riboflavin derivative that can be exploited to target the riboflavin transporters (RFTs) and the riboflavin carrier protein (RCP) in cells with high metabolic activity. In this study we present the synthesis of different FMN-coated ultrasmall superparamagnetic iron oxide nanoparticles (USPIOs) and their efficiency as targeting contrast agents. Since FMN alone cannot stabilize the nanoparticles, we used adenosine phosphates--AMP, ADP and ATP--as spacers to obtain colloidally stable nanoparticles. Nucleotides with di- and triphosphate groups were intended to increase the USPIO charge and thus improve zeta potential and stability. However, all nanoparticles formed negatively charged clusters with similar properties in terms of zeta potential (-28 ± 2 mV), relaxivity (228-259 mM(-1) s(-1) at 3 T) and hydrodynamic radius (53-85 nm). Molecules with a higher number of phosphate groups, such as ADP and ATP, have a higher adsorption affinity towards iron oxide, which, instead of providing more charge, led to partial desorption and replacement of FMN. Hence, we obtained USPIOs carrying different amounts of targeting agent, which significantly influenced the nanoparticles' uptake. The nanoparticles' uptake by different cancer cells and HUVECs was evaluated photometrically and with MR relaxometry, showing that the cellular uptake of the USPIOs increases with the FMN amount on their surface. Thus, for USPIOs targeted with riboflavin derivatives the use of spacers with increasing numbers of phosphate groups does not improve either zeta potential or the particles' stability, but rather detaches the targeting moieties from their surface, leading to lower cellular uptake.

  16. The influence of target erosion grade in the optoelectronic properties of AZO coatings growth by magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Zubizarreta, C.; G-Berasategui, E.; Ciarsolo, I.; Barriga, J.; Gaspar, D.; Martins, R.; Fortunato, E.

    2016-09-01

    Aluminum-doped zinc oxide (AZO) transparent conductor coating has emerged as promising substitute to tin-doped indium oxide (ITO) as electrode in optoelectronic applications such as photovoltaics or light emitting diodes (LEDs). Besides its high transmission in the visible spectral region and low resistivity, AZO presents a main advantage over other candidates such as graphene, carbon nanotubes or silver nanowires; it can be deposited using the technology industrially implemented to manufacture ITO layers, the magnetron sputtering (MS). This is a productive, reliable and green manufacturing technique. But to guarantee the robustness, reproducibility and reliability of the process there are still some issues to be addressed, such as the effect and control of the target state. In this paper a thorough study of the influence of the target erosion grade in developed coatings has been performed. AZO films have been deposited from a ceramic target by RF MS. Structure, optical transmittance and electrical properties of the produced coatings have been analyzed as function of the target erosion grade. No noticeable differences have been found neither in optoelectronic properties nor in the structure of the coatings, indicating that the RF MS is a stable and consistent process through the whole life of the target.

  17. The synthesis of Zr-Nb-N nanocomposite coating prepared by multi-target magnetron co-sputtering

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Wang, N.; Li, D. J.; Dong, L.; Gu, H. Q.; Wan, R. X.; Sun, X.

    2013-07-01

    Growth, structure, and mechanical properties of the nanocomposite Zr-Nb-N coatings deposited on Si(1 0 0) at different substrate bias voltages and substrate temperatures were performed by multi-target magnetron co-sputtering system. Extensive measurements were taken to investigate the influences of substrate bias voltage and deposition temperature on microstructure, hardness, elastic modulus, residual stress, critical fracture load. The maximum hardness and elastic modulus was up to 36 GPa and 425 GPa, respectively. The hardest coating also showed the lowest residual stress and the highest critical load. These enhancement effects should be related to nanocrystalline solid-solution microstructure formation and smaller grain size. These Zr-Nb-N coatings appeared to be a promising composite coating system suitable for engineering applications.

  18. Industrial recovered-materials-utilization targets for the metals and metal-products industry

    SciTech Connect

    1980-03-01

    The National Energy Conservation Policy Act of 1978 directs DOE to set targets for increased utilization of energy-saving recovered materials for certain industries. These targets are to be established at levels representing the maximum feasible increase in utilization of recovered materials that can be achieved progressively by January 1, 1987 and is consistent with technical and economic factors. A benefit to be derived from the increased use of recoverable materials is in energy savings, as state in the Act. Therefore, emhasis on different industries in the metals sector has been related to their energy consumption. The ferrous industry (iron and steel, ferrour foundries and ferralloys), as defined here, accounts for approximately 3%, and all others for the remaining 3%. Energy consumed in the lead and zinc segments is less than 1% each. Emphasis is placed on the ferrous scrap users, followed by the aluminum and copper industries. A bibliography with 209 citations is included.

  19. In-situ composite formation of damage tolerant coatings utilizing laser

    DOEpatents

    Blue, Craig A; Wong, Frank; Aprigliano, Louis F; Engleman, Peter G; Rozgonyi, Tibor G; Ozdemir, Levent

    2014-03-18

    A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.

  20. In-situ composite formation of damage tolerant coatings utilizing laser

    DOEpatents

    Blue, Craig A.; Wong, Frank; Aprigliano, Louis F.; Engleman, Peter G.; Peter, William H.; Rozgonyi, Tibor G; Ozdemir, Levent

    2011-05-10

    A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.

  1. In-situ composite formation of damage tolerant coatings utilizing laser

    DOEpatents

    Blue, Craig A.; Wong, Frank; Aprigliano, Louis F.; Engleman, Peter G.; Peter, William H.; Rozgonyi, Tibor G.; Ozdemir, Levent

    2016-05-24

    A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.

  2. PEGylated polydopamine-coated magnetic nanoparticles for combined targeted chemotherapy and photothermal ablation of tumour cells.

    PubMed

    Xue, Peng; Sun, Lihong; Li, Qian; Zhang, Lei; Guo, Jinhong; Xu, Zhigang; Kang, Yuejun

    2017-09-08

    The integration of multifunctional therapeutic capabilities into a single nanosystem has attracted much attention for use as an efficient cancer therapy. However, developing biocompatible therapeutic nano-agents with desirable safety, efficiency, targeting, and synergistic effects remains challenging. Herein, we designed a class of multifunctional PEGylated magnetic nanoparticles (NPs) with a core-shell structure and polydopamine (PDA) coating, which were loaded with the anticancer drug doxorubicin (DOX) for simultaneous targeted chemotherapy and photothermal ablation of tumour cells. This nanosystem showed strong near-infrared absorption due to the polydopamine layer and was capable of magnetic field-guided drug delivery due to the superparamagnetism of the carrier. The resultant product exhibited excellent stability and biocompatibility in vitro due to the PEGylation of dopamine. Notably, the combination of chemotherapy and photothermal therapy had an evident synergistic effect on the ablation of tumour cells. This multifunctional nanoplatform has promising potential as an efficient therapeutic agent for multimodal cancer treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Blunt Trauma Performance of Fabric Systems Utilizing Natural Rubber Coated High Strength Fabrics

    SciTech Connect

    Ahmad, M. R.; Ahmad, W. Y. W.; Samsuri, A.; Salleh, J.; Abidin, M. H.

    2010-03-11

    The blunt trauma performance of fabric systems against 9 mm bullets is reported. Three shots were fired at each fabric system with impact velocity of 367+-9 m/s and the depth of indentation on the modeling clay backing was measured. The results showed that 18-layer and 21-layer all-neat fabric systems failed the blunt trauma test. However, fabric systems with natural rubber (NR) latex coated fabric layers gave lower blunt trauma of between 25-32 mm indentation depths. Deformations on the neat fabrics upon impact were identified as broken yarns, yarn stretching and yarn pull-out. Deflections of the neat fabrics were more localised. For the NR latex coated fabric layers, no significant deformation can be observed except for peeled-off regions of the NR latex film at the back surface of the last layer. From the study, it can be said that the NR latex coated fabric layers were effective in reducing the blunt trauma of fabric systems.

  4. Blunt Trauma Performance of Fabric Systems Utilizing Natural Rubber Coated High Strength Fabrics

    NASA Astrophysics Data System (ADS)

    Ahmad, M. R.; Ahmad, W. Y. W.; Samsuri, A.; Salleh, J.; Abidin, M. H.

    2010-03-01

    The blunt trauma performance of fabric systems against 9 mm bullets is reported. Three shots were fired at each fabric system with impact velocity of 367±9 m/s and the depth of indentation on the modeling clay backing was measured. The results showed that 18-layer and 21-layer all-neat fabric systems failed the blunt trauma test. However, fabric systems with natural rubber (NR) latex coated fabric layers gave lower blunt trauma of between 25-32 mm indentation depths. Deformations on the neat fabrics upon impact were identified as broken yarns, yarn stretching and yarn pull-out. Deflections of the neat fabrics were more localised. For the NR latex coated fabric layers, no significant deformation can be observed except for peeled-off regions of the NR latex film at the back surface of the last layer. From the study, it can be said that the NR latex coated fabric layers were effective in reducing the blunt trauma of fabric systems.

  5. Polyethylene Glycol Modified, Cross-Linked Starch Coated Iron Oxide Nanoparticles for Enhanced Magnetic Tumor Targeting

    PubMed Central

    Cole, Adam J.; David, Allan E.; Wang, Jianxin; Galbán, Craig J.; Hill, Hannah L.; Yang, Victor C.

    2010-01-01

    While successful magnetic tumor targeting of iron oxide nanoparticles has been achieved in a number of models, the rapid blood clearance of magnetically suitable particles by the reticuloendothelial system (RES) limits their availability for targeting. This work aimed to develop a long-circulating magnetic iron oxide nanoparticle (MNP) platform capable of sustained tumor exposure via the circulation and, thus, enhanced magnetic tumor targeting. Aminated, cross-linked starch (DN) and aminosilane (A) coated MNPs were successfully modified with 5 kDa (A5, D5) or 20 kDa (A20, D20) polyethylene glycol (PEG) chains using simple N-Hydroxysuccinimide (NHS) chemistry and characterized. Identical PEG-weight analogues between platforms (A5 & D5, A20 & D20) were similar in size (140–190 nm) and relative PEG labeling (1.5% of surface amines – A5/D5, 0.4% – A20/D20), with all PEG-MNPs possessing magnetization properties suitable for magnetic targeting. Candidate PEG-MNPs were studied in RES simulations in vitro to predict long-circulating character. D5 and D20 performed best showing sustained size stability in cell culture medium at 37°C and 7 (D20) to 10 (D5) fold less uptake in RAW264.7 macrophages when compared to previously targeted, unmodified starch MNPs (D). Observations in vitro were validated in vivo, with D5 (7.29 hr) and D20 (11.75 hr) showing much longer half-lives than D (0.12 hr). Improved plasma stability enhanced tumor MNP exposure 100 (D5) to 150 (D20) fold as measured by plasma AUC0-∞ Sustained tumor exposure over 24 hours was visually confirmed in a 9L-glioma rat model (12 mg Fe/kg) using magnetic resonance imaging (MRI). Findings indicate that both D5 and D20 are promising MNP platforms for enhanced magnetic tumor targeting, warranting further study in tumor models. PMID:21176955

  6. Development and screening of a series of antibody-conjugated and silica coated iron-oxide nanoparticles for targeting the Prostate Specific Membrane Antigen

    PubMed Central

    Mukherjee, Amarnath; Darlington, Thomas; Baldwin, Richard; Holz, Charles; Olson, Sage; Kulkarni, Prakash; DeWeese, Theodore L.; Getzenberg, Robert H.; Ivkov, Robert

    2014-01-01

    The Prostate Specific Membrane Antigen (PSMA) is an established target for the delivery of cancer therapeutic and imaging agents due to its high expression on the surface of prostate cancer cells and within the neovasculature of other solid tumors. Here we describe the synthesis and screening of antibody-conjugated silica-coated iron oxide nanoparticles for PSMA-specific cell targeting. The humanized anti-PSMA antibody, HuJ591, was conjugated to a series of nanoparticles with varying densities of polyethylene glycol and primary amine groups. Customized assays utilizing iron spectral absorbance and Enzyme-Linked Immunoassay (ELISA) were developed to screen microgram quantities of nanoparticle formulations for immunoreactivity and cell targeting ability. Antibody and PSMA-specific targeting of the optimized nanoparticle was evaluated using an isogenic PSMA-positive and PSMA-negative cell line pair. Specific nanoparticle targeting was confirmed by iron quantification with inductively coupled plasma mass spectrometry (ICP-MS). These methods and nanoparticles support the promise of targeted theranostic agents for future treatment of prostate and other cancers. PMID:24591351

  7. Trastuzumab-conjugated liposome-coated fluorescent magnetic nanoparticles to target breast cancer.

    PubMed

    Jang, Mijung; Yoon, Young Il; Kwon, Yong Soo; Yoon, Tae-Jong; Lee, Hak Jong; Hwang, Sung Il; Yun, Bo La; Kim, Sun Mi

    2014-01-01

    To synthesize mesoporous silica-core-shell magnetic nanoparticles (MNPs) encapsulated by liposomes (Lipo [MNP@m-SiO2]) in order to enhance their stability, allow them to be used in any buffer solution, and to produce trastuzumab-conjugated (Lipo[MNP@m-SiO2]-Her2Ab) nanoparticles to be utilized in vitro for the targeting of breast cancer. The physiochemical characteristics of Lipo[MNP@m-SiO2] were assessed in terms of size, morphological features, and in vitro safety. The multimodal imaging properties of the organic dye incorporated into Lipo[MNP@m-SiO2] were assessed with both in vitro fluorescence and MR imaging. The specific targeting ability of trastuzumab (Her2/neu antibody, Herceptin®)-conjugated Lipo[MNP@m-SiO2] for Her2/neu-positive breast cancer cells was also evaluated with fluorescence and MR imaging. We obtained uniformly-sized and evenly distributed Lipo[MNP@m-SiO2] that demonstrated biological stability, while not disrupting cell viability. Her2/neu-positive breast cancer cell targeting by trastuzumab-conjugated Lipo[MNP@m-SiO2] was observed by in vitro fluorescence and MR imaging. Trastuzumab-conjugated Lipo[MNP@m-SiO2] is a potential treatment tool for targeted drug delivery in Her2/neu-positive breast cancer.

  8. Trastuzumab-Conjugated Liposome-Coated Fluorescent Magnetic Nanoparticles to Target Breast Cancer

    PubMed Central

    Jang, Mijung; Yoon, Young Il; Kwon, Yong Soo; Yoon, Tae-Jong; Lee, Hak Jong; Hwang, Sung Il; Yun, Bo La

    2014-01-01

    Objective To synthesize mesoporous silica-core-shell magnetic nanoparticles (MNPs) encapsulated by liposomes (Lipo [MNP@m-SiO2]) in order to enhance their stability, allow them to be used in any buffer solution, and to produce trastuzumab-conjugated (Lipo[MNP@m-SiO2]-Her2Ab) nanoparticles to be utilized in vitro for the targeting of breast cancer. Materials and Methods The physiochemical characteristics of Lipo[MNP@m-SiO2] were assessed in terms of size, morphological features, and in vitro safety. The multimodal imaging properties of the organic dye incorporated into Lipo[MNP@m-SiO2] were assessed with both in vitro fluorescence and MR imaging. The specific targeting ability of trastuzumab (Her2/neu antibody, Herceptin®)-conjugated Lipo[MNP@m-SiO2] for Her2/neu-positive breast cancer cells was also evaluated with fluorescence and MR imaging. Results We obtained uniformly-sized and evenly distributed Lipo[MNP@m-SiO2] that demonstrated biological stability, while not disrupting cell viability. Her2/neu-positive breast cancer cell targeting by trastuzumab-conjugated Lipo[MNP@m-SiO2] was observed by in vitro fluorescence and MR imaging. Conclusion Trastuzumab-conjugated Lipo[MNP@m-SiO2] is a potential treatment tool for targeted drug delivery in Her2/neu-positive breast cancer. PMID:25053899

  9. Utilization of advanced imaging technologies for target delineation in radiation oncology.

    PubMed

    Simpson, Daniel R; Lawson, Joshua D; Nath, Sameer K; Rose, Brent S; Mundt, Arno J; Mell, Loren K

    2009-12-01

    The aim of this study was to evaluate the utilization of advanced imaging technologies for target delineation among radiation oncologists in the United States. A random sample of 1,600 radiation oncologists was contacted by Internet, e-mail, and fax and questioned regarding the use of advanced imaging technologies, clinical applications, and future plans for use. Advanced imaging technologies were defined as any of the following that were directly incorporated into radiation therapy planning: MRI, PET, single-photon emission CT, 4-D CT, functional MRI, and MR spectroscopy. Of 1,089 contactable physicians, 394 (36%) responded. Of respondents, 65% were in private practice and 35% were in academic practice. The proportion using any advanced imaging technology for target delineation was 95%. However, the majority reported only rare (in <25% of their patients; 46.6%) or infrequent (in 25%-50% of their patients; 26.0%) utilization. The most commonly used technologies were 2-[(18)F]fluoro-2-deoxyglucose PET (76%), MRI (72%), and 4-D CT (44%). The most common cancers treated using image-guided target delineation were those of the lung (83%), central nervous system (79%), and head and neck (79%). Among users of advanced imaging technologies, 66% planned to increase use; 30% of nonusers planned to adopt these technologies in the future. Advanced imaging technologies are widely used by US radiation oncologists for target delineation. Although the majority of respondents used them in <50% of their patients, the frequency of utilization is expected to increase. Studies determining the optimal application of these technologies in radiation therapy planning are needed.

  10. Utility of the Biosynthetic Folate Pathway for Targets in Antimicrobial Discovery

    PubMed Central

    Bourne, Christina R.

    2014-01-01

    The need for new antimicrobials is great in face of a growing pool of resistant pathogenic organisms. This review will address the potential for antimicrobial therapy based on polypharmacological activities within the currently utilized bacterial biosynthetic folate pathway. The folate metabolic pathway leads to synthesis of required precursors for cellular function and contains a critical node, dihydrofolate reductase (DHFR), which is shared between prokaryotes and eukaryotes. The DHFR enzyme is currently targeted by methotrexate in anti-cancer therapies, by trimethoprim for antibacterial uses, and by pyrimethamine for anti-protozoal applications. An additional anti-folate target is dihyropteroate synthase (DHPS), which is unique to prokaryotes as they cannot acquire folate through dietary means. It has been demonstrated as a primary target for the longest standing antibiotic class, the sulfonamides, which act synergistically with DHFR inhibitors. Investigations have revealed most DHPS enzymes possess the ability to utilize sulfa drugs metabolically, producing alternate products that presumably inhibit downstream enzymes requiring the produced dihydropteroate. Recent work has established an off-target effect of sulfonamide antibiotics on a eukaryotic enzyme, sepiapterin reductase, causing alterations in neurotransmitter synthesis. Given that inhibitors of both DHFR and DHPS are designed to mimic their cognate substrate, which contain shared substructures, it is reasonable to expect such “off-target” effects. These inhibitors are also likely to interact with the enzymatic neighbors in the folate pathway that bind products of the DHFR or DHPS enzymes and/or substrates of similar substructure. Computational studies designed to assess polypharmacology reiterate these conclusions. This leads to hypotheses exploring the vast utility of multiple members of the folate pathway for modulating cellular metabolism, and includes an appealing capacity for prokaryotic

  11. Studies of the Cr-CrN coating characteristics formed by means of the magnetron sputtering method from bulk target

    NASA Astrophysics Data System (ADS)

    Kachalin, G. V.; Mednikov, A. F.; Tkhabisimov, A. B.; Sidorov, S. V.

    2017-07-01

    The paper presents the study’s results of ion-plasma chromium based coating characteristics produced on blade steel samples 12Kh13 and EI961 by means of the magnetron sputtering method from the bulk “hot” target. A set of metallographic studies and erosion tests of coatings were carried out using the research equipment URI (unique research installation) “Hydroshock rig Erosion-M” of NRU “MPEI”. Cr-CrN based coatings have a layered structure; thickness of intermediate Cr layers ranges from 0.7 to 1.7 μm, thickness of nitride layers CrN ranges from 1.5 to 4 μm, while the overall coating thickness is 17.0-21.5 μm coating microhardness is 1830-1880 HV0.05. The resulting coatings are found to increase 1.5 times the incubation period duration of erosion wear for steels 12Kh13 and EI961; they reduce the maximum erosion rate 1.3 times, and the steady erosion rate - 1.5 times.

  12. Development of a Glycosaminoglycan Derived, Selectin Targeting Anti-Adhesive Coating to Treat Endothelial Cell Dysfunction

    PubMed Central

    Wodicka, James R.; Chambers, Andrea M.; Sangha, Gurneet S.; Goergen, Craig J.; Panitch, Alyssa

    2017-01-01

    Endothelial cell (EC) dysfunction is associated with many disease states including deep vein thrombosis (DVT), chronic kidney disease, sepsis and diabetes. Loss of the glycocalyx, a thin glycosaminoglycan (GAG)-rich layer on the EC surface, is a key feature of endothelial dysfunction and increases exposure of EC adhesion molecules such as selectins, which are involved in platelet binding to ECs. Once bound, platelets cause thrombus formation and an increased inflammatory response. We have developed a GAG derived, selectin targeting anti-adhesive coating (termed EC-SEAL) consisting of a dermatan sulfate backbone and multiple selectin-binding peptides designed to bind to inflamed endothelium and prevent platelet binding to create a more quiescent endothelial state. Multiple EC-SEAL variants were evaluated and the lead variant was found to preferentially bind to selectin-expressing ECs and smooth muscle cells (SMCs) and inhibit platelet binding and activation in a dose-dependent manner. In an in vivo model of DVT, treatment with the lead variant resulted in reduced thrombus formation. These results indicate that EC-SEAL has promise as a potential therapeutic in the treatment of endothelial dysfunction. PMID:28353658

  13. Drug loaded silica coated MnFe2O4 ferromagnetic biomaterials for targeted cancer treatment

    NASA Astrophysics Data System (ADS)

    Anand, Vikas; Singh, K. J.; Kaur, Kulwinder; Bhatia, Gaurav

    2017-05-01

    Magnetically attracted silica coated MnFe2O4 samples have been prepared by using co-precipitation method. Structural changes have been confirmed from XRD spectra. Ferromagnetic behavior of samples has been studied by using vibration sample magnetometer. Cytotoxicity and cell culture of samples have been investigated by using human MG63 cell line and found that sample provide a healthy environment to the growth of cell lines. Drug carrier ability of sample has been checked with gentamycin as an antibiotic and results show that sample can be used as excellent drug carriers. Drug loaded samples can be easily targeted to specific area due to their attractive nature towards external magnetic field. Moreover, magnetic nanoparticles can also be used to kill the cancer cells by using hyperthermia technique. Hyperthermia is a process to raise the temperature of surrounding cells in the presence of external AC magnetic field above the maximum temperature limit for surviving of the cancer cells. Cancer cell can survive only up to 47°C. After that cancer cells start to die, but healthy cells can easily survive up to higher temperature. Our results indicate that prepared samples possess good drug carrier ability and hence, can be potential candidates for cancer cell treatment.

  14. Targeted intracellular voltage recordings from dendritic spines using quantum-dot-coated nanopipettes

    NASA Astrophysics Data System (ADS)

    Jayant, Krishna; Hirtz, Jan J.; Plante, Ilan Jen-La; Tsai, David M.; de Boer, Wieteke D. A. M.; Semonche, Alexa; Peterka, Darcy S.; Owen, Jonathan S.; Sahin, Ozgur; Shepard, Kenneth L.; Yuste, Rafael

    2017-05-01

    Dendritic spines are the primary site of excitatory synaptic input onto neurons, and are biochemically isolated from the parent dendritic shaft by their thin neck. However, due to the lack of direct electrical recordings from spines, the influence that the neck resistance has on synaptic transmission, and the extent to which spines compartmentalize voltage, specifically excitatory postsynaptic potentials, albeit critical, remains controversial. Here, we use quantum-dot-coated nanopipette electrodes (tip diameters ∼15-30 nm) to establish the first intracellular recordings from targeted spine heads under two-photon visualization. Using simultaneous somato-spine electrical recordings, we find that back propagating action potentials fully invade spines, that excitatory postsynaptic potentials are large in the spine head (mean 26 mV) but are strongly attenuated at the soma (0.5-1 mV) and that the estimated neck resistance (mean 420 MΩ) is large enough to generate significant voltage compartmentalization. Nanopipettes can thus be used to electrically probe biological nanostructures.

  15. Chemical and genetic validation of thiamine utilization as an antimalarial drug target.

    PubMed

    Chan, Xie Wah Audrey; Wrenger, Carsten; Stahl, Katharina; Bergmann, Bärbel; Winterberg, Markus; Müller, Ingrid B; Saliba, Kevin J

    2013-01-01

    Thiamine is metabolized into an essential cofactor for several enzymes. Here we show that oxythiamine, a thiamine analog, inhibits proliferation of the malaria parasite Plasmodium falciparum in vitro via a thiamine-related pathway and significantly reduces parasite growth in a mouse malaria model. Overexpression of thiamine pyrophosphokinase (the enzyme that converts thiamine into its active form, thiamine pyrophosphate) hypersensitizes parasites to oxythiamine by up to 1,700-fold, consistent with oxythiamine being a substrate for thiamine pyrophosphokinase and its conversion into an antimetabolite. We show that parasites overexpressing the thiamine pyrophosphate-dependent enzymes oxoglutarate dehydrogenase and pyruvate dehydrogenase are up to 15-fold more resistant to oxythiamine, consistent with the antimetabolite inactivating thiamine pyrophosphate-dependent enzymes. Our studies therefore validate thiamine utilization as an antimalarial drug target and demonstrate that a single antimalarial can simultaneously target several enzymes located within distinct organelles.

  16. Identification of Capsid/Coat Related Protein Folds and Their Utility for Virus Classification

    PubMed Central

    Nasir, Arshan; Caetano-Anollés, Gustavo

    2017-01-01

    The viral supergroup includes the entire collection of known and unknown viruses that roam our planet and infect life forms. The supergroup is remarkably diverse both in its genetics and morphology and has historically remained difficult to study and classify. The accumulation of protein structure data in the past few years now provides an excellent opportunity to re-examine the classification and evolution of viruses. Here we scan completely sequenced viral proteomes from all genome types and identify protein folds involved in the formation of viral capsids and virion architectures. Viruses encoding similar capsid/coat related folds were pooled into lineages, after benchmarking against published literature. Remarkably, the in silico exercise reproduced all previously described members of known structure-based viral lineages, along with several proposals for new additions, suggesting it could be a useful supplement to experimental approaches and to aid qualitative assessment of viral diversity in metagenome samples. PMID:28344575

  17. A new method for infiltration coating complex geometry matrices with compound materials for ISOL production target applications

    NASA Astrophysics Data System (ADS)

    Alton, G. D.; Bilheux, J.-C.; McMillan, A. D.

    2004-03-01

    Although a number of methods have been developed for depositing films of production target materials onto surfaces with thickness commensurate with fast diffusion release of short-lived radioactive species for Isotope Separator On-Line (ISOL) target applications, the methods are either inappropriate for coating interior surfaces of highly permeable matrices (non-infiltrating, non-penetrating) or require complex chemical processes that are only available for depositing a limited number of elemental or compound materials. A simple, fast, inexpensive and close to universal method, based on suspension of finely divided target material in a binder to form a paint, has been developed that can be vacuum infiltrated to uniformly coat the surfaces of highly permeable fibrous target matrices with compound target materials and thus, form fast diffusion-release, mechanically and thermally stable production targets for ISOL-based radioactive ion beam research applications. In this report, the paint infiltration technique is described and the universal character of the technique illustrated by preparing several nitride, carbide, oxide and sulfide targets for potential use at the Holifield Radioactive Ion Beam Facility or at future high energy ISOL-based research facilities such as the Rare Isotope Accelerator facility, now under proposal for construction in the USA.

  18. Utilizing G2/M retention effect to enhance tumor accumulation of active targeting nanoparticles

    PubMed Central

    Hu, Guanlian; Cun, Xingli; Ruan, Shaobo; Shi, Kairong; Wang, Yang; Kuang, Qifang; Hu, Chuan; Xiao, Wei; He, Qin; Gao, Huile

    2016-01-01

    In recent years, active targeting strategies by ligand modification have emerged to enhance tumor accumulation of NP, but their clinical application was strictly restricted due to the complex preparation procedures, poor stability and serious toxicity. An effective and clinical translational strategy is required to satisfy the current problems. Interestingly, the internalization of NP is intimately related with cell cycle and the expression of receptors is not only related with cancer types but also cell cycle progression. So the cellular uptake of ligand modified NP may be related with cell cycle. However, few investigations were reported about the relationship between cell cycle and the internalization of ligand modified NP. Herein, cellular uptake of folic acid (FA) modified NP after utilizing chemotherapeutic to retain the tumor cells in G2/M phase was studied and a novel strategy was designed to enhance the active targeting effect. In our study, docetaxel (DTX) notably synchronized cells in G2/M phase and pretreatment with DTX highly improved in vitro and in vivo tumor cell targeting effect of FA decorated NP (FANP). Since FA was a most common used tumor active targeting ligand, we believe that this strategy possesses broader prospects in clinical application for its simplicity and effectiveness. PMID:27273770

  19. Utilizing Chemical Genomics to Identify Cytochrome b as a Novel Drug Target for Chagas Disease

    PubMed Central

    Khare, Shilpi; Roach, Steven L.; Barnes, S. Whitney; Hoepfner, Dominic; Walker, John R.; Chatterjee, Arnab K.; Neitz, R. Jeffrey; Arkin, Michelle R.; McNamara, Case W.; Ballard, Jaime; Lai, Yin; Fu, Yue; Molteni, Valentina; Yeh, Vince; McKerrow, James H.; Glynne, Richard J.; Supek, Frantisek

    2015-01-01

    Unbiased phenotypic screens enable identification of small molecules that inhibit pathogen growth by unanticipated mechanisms. These small molecules can be used as starting points for drug discovery programs that target such mechanisms. A major challenge of the approach is the identification of the cellular targets. Here we report GNF7686, a small molecule inhibitor of Trypanosoma cruzi, the causative agent of Chagas disease, and identification of cytochrome b as its target. Following discovery of GNF7686 in a parasite growth inhibition high throughput screen, we were able to evolve a GNF7686-resistant culture of T. cruzi epimastigotes. Clones from this culture bore a mutation coding for a substitution of leucine by phenylalanine at amino acid position 197 in cytochrome b. Cytochrome b is a component of complex III (cytochrome bc1) in the mitochondrial electron transport chain and catalyzes the transfer of electrons from ubiquinol to cytochrome c by a mechanism that utilizes two distinct catalytic sites, QN and QP. The L197F mutation is located in the QN site and confers resistance to GNF7686 in both parasite cell growth and biochemical cytochrome b assays. Additionally, the mutant cytochrome b confers resistance to antimycin A, another QN site inhibitor, but not to strobilurin or myxothiazol, which target the QP site. GNF7686 represents a promising starting point for Chagas disease drug discovery as it potently inhibits growth of intracellular T. cruzi amastigotes with a half maximal effective concentration (EC50) of 0.15 µM, and is highly specific for T. cruzi cytochrome b. No effect on the mammalian respiratory chain or mammalian cell proliferation was observed with up to 25 µM of GNF7686. Our approach, which combines T. cruzi chemical genetics with biochemical target validation, can be broadly applied to the discovery of additional novel drug targets and drug leads for Chagas disease. PMID:26186534

  20. Analyzing freely dissolved concentrations of cationic surfactant utilizing ion-exchange capability of polyacrylate coated solid-phase microextraction fibers.

    PubMed

    Chen, Yi; Droge, Steven T J; Hermens, Joop L M

    2012-08-24

    A 7-μm polyacrylate (PA) coated fiber was successfully employed to determine freely dissolved concentrations of cationic surfactants by solid-phase microextraction (SPME) and utilizing the capability of the PA-coating to sorb organic cations via ion-exchange at carboxylic groups. Measured fiber-water partitioning coefficients (K(fw)) were constant below a fiber loading of 2mmol per liter polyacrylate, allowing for simple and accurate analysis in a concentration range that is relevant from a risk assessment point of view. Ion-exchange was confirmed to be the main sorption mechanism because of a decreasing K(fw) with either higher CaCl(2) concentrations or lower pH, and maximum fiber uptake at the polyacrylate cation-exchange capacity (CEC, at 30mmol/L PA). Fiber-water sorption isotherms were established in various aqueous media in toxicological relevant concentrations. The developed SPME method has a high potential for application in ecotoxicological studies, as demonstrated in sorption studies with humic acid in different electrolyte solutions at aqueous concentrations down to the sub nM range. Cationic surfactant sorption affinities for humic acid also depend on medium composition but are orders of magnitude higher than to the PA fiber on a sorbent weight basis. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Targeted delivery of tissue plasminogen activator by binding to silica-coated magnetic nanoparticle

    PubMed Central

    Chen, Jyh-Ping; Yang, Pei-Ching; Ma, Yunn-Hwa; Tu, Su-Ju; Lu, Yu-Jen

    2012-01-01

    Background and methods Silica-coated magnetic nanoparticle (SiO2-MNP) prepared by the sol-gel method was studied as a nanocarrier for targeted delivery of tissue plasminogen activator (tPA). The nanocarrier consists of a superparamagnetic iron oxide core and an SiO2 shell and is characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, superconducting quantum interference device, and thermogravimetric analysis. An amine-terminated surface silanizing agent (3-aminopropyltrimethoxysilane) was used to functionalize the SiO2 surface, which provides abundant –NH2 functional groups for conjugating with tPA. Results The optimum drug loading is reached when 0.5 mg/mL tPA is conjugated with 5 mg SiO2-MNP where 94% tPA is attached to the carrier with 86% retention of amidolytic activity and full retention of fibrinolytic activity. In vitro biocompatibility determined by lactate dehydrogenase release and cell proliferation indicated that SiO2-MNP does not elicit cytotoxicity. Hematological analysis of blood samples withdrawn from mice after venous administration indicates that tPA-conjugated SiO2-MNP (SiO2-MNP-tPA) did not alter blood component concentrations. After conjugating to SiO2-MNP, tPA showed enhanced storage stability in buffer and operation stability in whole blood up to 9.5 and 2.8-fold, respectively. Effective thrombolysis with SiO2-MNP-tPA under magnetic guidance is demonstrated in an ex vivo thrombolysis model where 34% and 40% reductions in blood clot lysis time were observed compared with runs without magnetic targeting and with free tPA, respectively, using the same drug dosage. Enhanced penetration of SiO2-MNP-tPA into blood clots under magnetic guidance was confirmed from microcomputed tomography analysis. Conclusion Biocompatible SiO2-MNP developed in this study will be useful as a magnetic targeting drug carrier to improve clinical thrombolytic therapy. PMID:23055726

  2. Rapid amplification/detection of nucleic acid targets utilizing a HDA/thin film biosensor.

    PubMed

    Jenison, Robert; Jaeckel, Heidi; Klonoski, Joshua; Latorra, David; Wiens, Jacinta

    2014-08-07

    Thin film biosensors exploit a flat, optically coated silicon-based surface whereupon formation of nucleic acid hybrids are enzymatically transduced in a molecular thin film that can be detected by the unaided human eye under white light. While the limit of sensitivity for detection of nucleic acid targets is at sub-attomole levels (60 000 copies) many clinical specimens containing bacterial pathogens have much lower levels of analyte present. Herein, we describe a platform, termed HDA/thin film biosensor, which performs helicase-dependant nucleic acid amplification on a thin film biosensor surface to improve the limit of sensitivity to 10 copies of the mecA gene present in methicillin-resistant strains of Staphylococcus. As double-stranded DNA is unwound by helicase it was either bound by solution-phase DNA primers to be copied by DNA polymerase or hybridized to surface immobilized probe on the thin film biosensor surface to be detected. Herein, we show that amplification reactions on the thin film biosensor are equivalent to in standard thin wall tubes, with detection at the limit of sensitivity of the assay occurring after 30 minutes of incubation time. Further we validate the approach by detecting the presence of the mecA gene in methicillin-resistant Staphylococcus aureus (MRSA) from positive blood culture aliquots with high specificity (signal/noise ratio of 105).

  3. Radiographic detection of 100 A thickness variations in 1-micron-thick coatings applied to submillimeter -diameter laser fusion targets

    NASA Astrophysics Data System (ADS)

    Stupin, D. M.

    We have developed X-ray radiography to measure thickness variations of coatings on laser fusion targets. Our technique is based on measuring the variation in X-ray transmission through the targets. The simplest targets are hollow glass microshells or microballoons 100 to 500 m in diameter, that have several layers of metals or plastics, 1 to 100 m thick. Our goal is to examine these opaque coatings for thickness variations as small as 1% or 0.1%, depending on the type of defect. Using contact radiography we have obtained the desired sensitivity for concentric and elliptical defects of 1%. This percentage corresponds to thickness variations as small as 100 A in a 1-m-thick coating. For warts and dimples, the desired sensitivity is a function of the area of the defect, and we are developing a system to detect 0.1% thickness variations that cover an area 10 m by 10 m. We must use computer analysis of contact radiographs to measure 1% thickness variations in either concentricity or ellipticity. Because this analysis takes so long on our minicomputer, we preselect the radiographs by looking for defects at the 10% level on a video image analysis system.

  4. Targeting vascular amyloid in arterioles of Alzheimer disease transgenic mice with amyloid β protein antibody-coated nanoparticles.

    PubMed

    Poduslo, Joseph F; Hultman, Kristi L; Curran, Geoffry L; Preboske, Gregory M; Chamberlain, Ryan; Marjańska, Małgorzata; Garwood, Michael; Jack, Clifford R; Wengenack, Thomas M

    2011-08-01

    The relevance of cerebral amyloid angiopathy (CAA) to the pathogenesis of Alzheimer disease (AD) and dementia in general emphasizes the importance of developing novel targeting approaches for detecting and treating cerebrovascular amyloid (CVA) deposits. We developed a nanoparticle-based technology that uses a monoclonal antibody against fibrillar human amyloid-β42 that is surface coated onto a functionalized phospholipid monolayer. We demonstrate that this conjugated nanoparticle binds to CVA deposits in arterioles of AD transgenic mice (Tg2576) after infusion into the external carotid artery using 3 different approaches. The first 2 approaches use a blood vessel enrichment of homogenized brain and a leptomeningeal vessel preparation from thin tangential brain slices from the surface of the cerebral cortex. Targeting of CVA by the antibody-coated nanoparticle was visualized using fluorescent lissamine rhodamine-labeled phospholipids in the nanoparticles, which were compared with fluorescent staining of the endothelial cells and amyloid deposits using confocal laser scanning microscopy. The third approach used high-field strength magnetic resonance imaging of antibody-coated iron oxide nanoparticles after infusion into the external carotid artery. Dark foci of contrast enhancement in cortical arterioles were observed in T2*-weighted images of ex vivo AD mouse brains that correlated histologically with CVA deposits. The targeting ability of these nanoparticles to CVA provides opportunities for the prevention and treatment of CAA.

  5. Analytic expressions for Atomic Layer Deposition: coverage, throughput, and materials utilization in cross-flow, particle coating, and spatial ALD

    SciTech Connect

    Yanguas-Gil, Angel; Elam, Jeffrey W.

    2014-05-01

    In this work, the authors present analytic models for atomic layer deposition (ALD) in three common experimental configurations: cross-flow, particle coating, and spatial ALD. These models, based on the plug-flow and well-mixed approximations, allow us to determine the minimum dose times and materials utilization for all three configurations. A comparison between the three models shows that throughput and precursor utilization can each be expressed by universal equations, in which the particularity of the experimental system is contained in a single parameter related to the residence time of the precursor in the reactor. For the case of cross-flow reactors, the authors show how simple analytic expressions for the reactor saturation profiles agree well with experimental results. Consequently, the analytic model can be used to extract information about the ALD surface chemistry (e. g., the reaction probability) by comparing the analytic and experimental saturation profiles, providing a useful tool for characterizing new and existing ALD processes. (C) 2014 American Vacuum Society

  6. Development and evaluation of chitosan and chitosan/Kollicoat® Smartseal 30 D film-coated tablets for colon targeting.

    PubMed

    Drechsler, Michael; Garbacz, Grzegorz; Thomann, Ralf; Schubert, Rolf

    2014-11-01

    The aim of the present study was to develop film-coated tablets which release a minor amount of the active pharmaceutical ingredient (API) into the stomach and small intestine, yet show a sharp increase of drug release in the colon. Tablets containing the model drug Diclofenac-Na, microcrystalline cellulose as a filler (MT), as well as tablets consisting of Ludiflash® (LT), both were used as tablet cores, respectively. Either chitosan (CHI) alone or different ratios of chitosan and Kollicoat® Smartseal 30 D (KCSS) were applied onto these cores. The resulting film-coated tablets were analyzed for swelling, drug dissolution and stability. In order to clarify whether the colon release is mainly enzyme-driven or pressure-controlled, the coated tablets were both tested in the colon microflora test (CMT), which simulates the enzyme environment within the colon, and using a bio-relevant dissolution apparatus mimicking the intraluminal pressures and stress conditions present in the gastrointestinal tract (GIT). CHI/KCSS (25:75) coated LTs showed a pressure-controlled site-specific drug release in the large intestine, while remaining intact in the upper GIT. CHI as well as CHI/KCSS (25:75) applied onto MTs, remained stable during the entire simulated bio-relevant dissolution transit of the GIT, but showed enzymatically controlled colon targeting in the CMT. These results could be confirmed for CHI/KCSS (25:75) film-coated MTs top-coated with an additional hydroxypropylmethylcellulose (HPMC) layer and an Eudragit L 30 D-55 (EUL) layer to avoid the dissolution in the fasting stomach. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Utilization of star-shaped polymer architecture in the creation of high-density polymer brush coatings for the prevention of platelet and bacteria adhesion.

    PubMed

    Totani, Masayasu; Ando, Tsuyoshi; Terada, Kayo; Terashima, Takaya; Kim, Ill Yong; Ohtsuki, Chikara; Xi, Chuanwu; Kuroda, Kenichi; Tanihara, Masao

    2014-09-01

    We demonstrate utilization of star-shaped polymers as high-density polymer brush coatings and their effectiveness to inhibit the adhesion of platelets and bacteria. Star polymers consisting of poly(2-hydroxyethyl methacrylate) (PHEMA) and/or poly(methyl methacrylate) (PMMA), were synthesized using living radical polymerization with a ruthenium catalyst. The polymer coatings were prepared by simple drop casting of the polymer solution onto poly(ethylene terephthalate) (PET) surfaces and then dried. Among the star polymers prepared in this study, the PHEMA star polymer (star-PHEMA) and the PHEMA/PMMA (mol. ratio of 71/29) heteroarm star polymer (star-H71M29) coatings showed the highest percentage of inhibition against platelet adhesion (78-88% relative to noncoated PET surface) and Escherichia coli (94-97%). These coatings also showed anti-adhesion activity against platelets after incubation in Dulbecco's phosphate buffered saline or surfactant solution for 7 days. In addition, the PMMA component of the star polymers increased the scratch resistance of the coating. These results indicate that the star-polymer architecture provides high polymer chain density on PET surfaces to prevent adhesion of platelets and bacteria, as well as coating stability and physical durability to prevent exposure of bare PET surfaces. The star polymers provide a simple and effective approach to preparing anti-adhesion polymer coatings on biomedical materials against the adhesion of platelets and bacteria.

  8. Expression of tomato yellow leaf curl virus coat protein using baculovirus expression system and evaluation of its utility as a viral antigen.

    PubMed

    Elgaied, Lamiaa; Salem, Reda; Elmenofy, Wael

    2017-08-01

    DNA encoding the coat protein (CP) of an Egyptian isolate of tomato yellow leaf curl virus (TYLCV) was inserted into the genome of Autographa californica nucleopolyhedrovirus (AcNPV) under the control of polyhedrin promoter. The generated recombinant baculovirus construct harboring the coat protein gene was characterized using PCR analysis. The recombinant coat protein expressed in infected insect cells was used as a coating antigen in an indirect Enzyme-linked immunosorbent assay (ELISA) and dot blot to test its utility for the detection of antibody generated against TYLCV virus particles. The results of ELISA and dot blot showed that the TYLCV-antibodies reacted positively with extracts of infected cells using the recombinant virus as a coating antigen with strong signals as well as the TYLCV infected tomato and beat plant extracts as positive samples. Scanning electron microscope examination showed that the expressed TYLCV coat protein was self-assembled into virus-like particles (VLPs) similar in size and morphology to TYLCV virus particles. These results concluded that, the expressed coat protein of TYLCV using baculovirus vector system is a reliable candidate for generation of anti-CP antibody for inexpensive detection of TYLCV-infected plants using indirect CP-ELISA or dot blot with high specificity.

  9. Utilization of star-shaped polymer architecture in the creation of high-density polymer brush coatings for the prevention of platelet and bacteria adhesion

    PubMed Central

    Totani, Masayasu; Terada, Kayo; Terashima, Takaya; Kim, Ill Yong; Ohtsuki, Chikara; Xi, Chuanwu; Tanihara, Masao

    2014-01-01

    We demonstrate utilization of star-shaped polymers as high-density polymer brush coatings and their effectiveness to inhibit the adhesion of platelets and bacteria. Star polymers consisting of poly(2-hydroxyethyl methacrylate) (PHEMA) and/or poly(methyl methacrylate) (PMMA), were synthesized using living radical polymerization with a ruthenium catalyst. The polymer coatings were prepared by simple drop casting of the polymer solution onto poly(ethylene terephthalate) (PET) surfaces and then dried. Among the star polymers prepared in this study, the PHEMA star polymer (star-PHEMA) and the PHEMA/PMMA (mol. ratio of 71/29) heteroarm star polymer (star-H71M29) coatings showed the highest percentage of inhibition against platelet adhesion (78–88% relative to noncoated PET surface) and Escherichia coli (94–97%). These coatings also showed anti-adhesion activity against platelets after incubation in Dulbecco's phosphate buffered saline or surfactant solution for 7 days. In addition, the PMMA component of the star polymers increased the scratch resistance of the coating. These results indicate that the star-polymer architecture provides high polymer chain density on PET surfaces to prevent adhesion of platelets and bacteria, as well as coating stability and physical durability to prevent exposure of bare PET surfaces. The star polymers provide a simple and effective approach to preparing anti-adhesion polymer coatings on biomedical materials against the adhesion of platelets and bacteria. PMID:25485105

  10. Characterization of alendronic- and undecylenic acid coated magnetic nanoparticles for the targeted delivery of rosiglitazone to subcutaneous adipose tissue.

    PubMed

    Saatchi, Katayoun; Tod, Sarah E; Leung, Donna; Nicholson, Kenton E; Andreu, Irene; Buchwalder, Christian; Schmitt, Veronika; Häfeli, Urs O; Gray, Sarah L

    2017-02-01

    Obesity is a state of positive energy balance where excess white adipose tissue accumulates to the detriment of metabolic health. Improving adipocyte function with systemic administration of thiazolidinediones (TZDs) improves metabolic outcomes in obesity, however TZD use is limited clinically due to undesirable side effects. Here we evaluate magnetic nanoparticles (MNPs) as a tool to target rosiglitazone (Rosi) specifically to adipose tissue. Results show Rosi can be adsorbed to MNPs (Rosi-MNPs) with hydrophobic coatings for which we present binding and release kinetics. Rosi adsorbed to MNPs retained the ability to induce PPARγ target gene expression in cells. Biodistribution analysis of radiolabeled Rosi-MNPs revealed a fat-implanted magnet significantly enhanced localization of Rosi to the targeted adipose tissue when administered by subcutaneous injection to obese mice. We propose MNPs for targeted delivery of anti-diabetic agents to superficially located subcutaneous adipose tissue.

  11. Target and non-target analysis of migrants from PVC-coated cans using UHPLC-Q-Orbitrap MS: evaluation of long-term migration testing.

    PubMed

    Vaclavikova, Marta; Paseiro-Cerrato, Rafael; Vaclavik, Lukas; Noonan, Gregory O; DeVries, Jonathan; Begley, Timothy H

    2016-01-01

    A simple, rapid and sensitive method for analyzing multi-target and non-target additives in polyvinyl chloride (PVC) food can coatings using ultra-high-performance liquid chromatography coupled to quadrupole-orbital ion-trap mass spectrometry was developed. This procedure was used to study the behaviour of a cross-linking agent, benzoguanamine (BGA), two slip agents, oleamide and erucamide, and 18 other commonly used plasticisers including phthalates, adipates, sebacates, acetyl tributyl citrate and epoxidised soybean or linseed oils. This optimised method was used to detect these analytes in food simulants (water and 3% acetic acid) in a long-term migration test of PVC-coated food cans for a period ranging from 1 day to 1.5 years at 40°C. Although very low detection limits (5 ng ml(-1)) were obtained for the majority of compounds, none of the monitored plasticisers and slip agents was detected in simulants extracted from cans over the period of the test. However, the presence of BGA in both aqueous food simulants was confirmed based on high-resolution mass spectrometry, product ion spectra and analysis of a reference standard. The BGA concentration in both simulants continued to increase with storage time: after 1.5 years storage in aqueous food simulants at 40°C, BGA was detected at concentrations up to 84 µg dm(-2). We believe this is the first study describing the long-term migration capacity of BGA from any vinyl coating material intended for use in PVC-coated food cans. Our results may have implications for migration test protocols for food cans that will be stored for extended time periods.

  12. The Role of Clusterin in Carcinogenesis and its Potential Utility as Therapeutic Target.

    PubMed

    Tellez, T; Garcia-Aranda, M; Redondo, M

    2016-01-01

    Clusterin is a glycoprotein that has been implicated in many processes, including apoptosis, cell cycle regulation and DNA repair. Since clusterin expression has also been associated with tumorigenesis and the progression of various malignancies including prevalent tumors like prostate, colon, bladder and breast, this protein has been proposed as a good candidate for future treatments. There have been numerous studies conducted in cell lines and xenograft models with successful results that, in general, justify the use of clusterin as a therapeutic target. However, it is still necessary to continue with these studies in order to achieve a better understanding of the role of this protein in carcinogenesis and to determine those specific situations in which its therapeutic use may be more favorable. In this review, we will make a brief description of clusterin structure and genetics, its implication in tumorigenesis and cancer progression and its prognosis utility. Finally, we will analyze the effects of clusterin inhibition in different types of cancer.

  13. Targeting of Magnetic Nanoparticle-coated Microbubbles to the Vascular Wall Empowers Site-specific Lentiviral Gene Delivery in vivo

    PubMed Central

    Heun, Yvonn; Hildebrand, Staffan; Heidsieck, Alexandra; Gleich, Bernhard; Anton, Martina; Pircher, Joachim; Ribeiro, Andrea; Mykhaylyk, Olga; Eberbeck, Dietmar; Wenzel, Daniela; Pfeifer, Alexander; Woernle, Markus; Krötz, Florian; Pohl, Ulrich; Mannell, Hanna

    2017-01-01

    In the field of vascular gene therapy, targeting systems are promising advancements to improve site-specificity of gene delivery. Here, we studied whether incorporation of magnetic nanoparticles (MNP) with different magnetic properties into ultrasound sensitive microbubbles may represent an efficient way to enable gene targeting in the vascular system after systemic application. Thus, we associated novel silicon oxide-coated magnetic nanoparticle containing microbubbles (SO-Mag MMB) with lentiviral particles carrying therapeutic genes and determined their physico-chemical as well as biological properties compared to MMB coated with polyethylenimine-coated magnetic nanoparticles (PEI-Mag MMB). While there were no differences between both MMB types concerning size and lentivirus binding, SO-Mag MMB exhibited superior characteristics regarding magnetic moment, magnetizability as well as transduction efficiency under static and flow conditions in vitro. Focal disruption of lentiviral SO-Mag MMB by ultrasound within isolated vessels exposed to an external magnetic field decisively improved localized VEGF expression in aortic endothelium ex vivo and enhanced the angiogenic response. Using the same system in vivo, we achieved a highly effective, site-specific lentiviral transgene expression in microvessels of the mouse dorsal skin after arterial injection. Thus, we established a novel lentiviral MMB technique, which has great potential towards site-directed vascular gene therapy. PMID:28042335

  14. Targeting of Magnetic Nanoparticle-coated Microbubbles to the Vascular Wall Empowers Site-specific Lentiviral Gene Delivery in vivo.

    PubMed

    Heun, Yvonn; Hildebrand, Staffan; Heidsieck, Alexandra; Gleich, Bernhard; Anton, Martina; Pircher, Joachim; Ribeiro, Andrea; Mykhaylyk, Olga; Eberbeck, Dietmar; Wenzel, Daniela; Pfeifer, Alexander; Woernle, Markus; Krötz, Florian; Pohl, Ulrich; Mannell, Hanna

    2017-01-01

    In the field of vascular gene therapy, targeting systems are promising advancements to improve site-specificity of gene delivery. Here, we studied whether incorporation of magnetic nanoparticles (MNP) with different magnetic properties into ultrasound sensitive microbubbles may represent an efficient way to enable gene targeting in the vascular system after systemic application. Thus, we associated novel silicon oxide-coated magnetic nanoparticle containing microbubbles (SO-Mag MMB) with lentiviral particles carrying therapeutic genes and determined their physico-chemical as well as biological properties compared to MMB coated with polyethylenimine-coated magnetic nanoparticles (PEI-Mag MMB). While there were no differences between both MMB types concerning size and lentivirus binding, SO-Mag MMB exhibited superior characteristics regarding magnetic moment, magnetizability as well as transduction efficiency under static and flow conditions in vitro. Focal disruption of lentiviral SO-Mag MMB by ultrasound within isolated vessels exposed to an external magnetic field decisively improved localized VEGF expression in aortic endothelium ex vivo and enhanced the angiogenic response. Using the same system in vivo, we achieved a highly effective, site-specific lentiviral transgene expression in microvessels of the mouse dorsal skin after arterial injection. Thus, we established a novel lentiviral MMB technique, which has great potential towards site-directed vascular gene therapy.

  15. Laser Desorption/Ionization Mass Spectrometry (LDI-MS) of Lipids with Iron Oxide Nanoparticle-Coated Targets

    PubMed Central

    Kusano, Maiko; Kawabata, Shin-ichirou; Tamura, Yusuke; Mizoguchi, Daigou; Murouchi, Masato; Kawasaki, Hideya; Arakawa, Ryuichi; Tanaka, Koichi

    2014-01-01

    Iron oxide nanoparticle (NP)-coated target plates were employed for the direct detection and analysis of low molecular weight lipids by laser desorption/ionization (LDI) mass spectrometry (MS). We have demonstrated that the use of the iron oxide NP-coated target provides a simple, direct, and rapid detection method for lipid standards and epidermal surface lipids without any cumbersome sample pretreatment as well as mass spectra that are free of background matrix peaks. Lipid standards (1-stearoyl-sn-glycero-3-phosphocholine, 1,2-dioleoyl-sn-glycerol, 1-palmitoyl-2-oleoyl-3-linoleoyl-rac-glycerol, 1,2-distearoyl-sn-glycero-3-phosphocholine) were detected as either protonated or cationated species. Clean MS/MS spectra for each lipid were also successfully obtained. Pre-MS surface cleaning of the target plates with UV-ozone treatment successfully removed organic contaminants that would interfere with the mass spectra especially in the low molecular weight region. Preliminary application of the presented target plate to the detection of endogenous lipids in latent fingerprints showed promising results and for potential use in the visualization and chemical composition determination of latent fingerprints by nanoparticle assistance. PMID:24860715

  16. Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice

    PubMed Central

    Weinandy, Stefan; Schreiber, Fabian; Megens, Remco T. A.; Theelen, Wendy; Smeets, Ralf; Jockenhövel, Stefan; Gries, Thomas; Möller, Martin; Klee, Doris; Weber, Christian; Zernecke, Alma

    2016-01-01

    Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches. PMID:27192172

  17. Asn-Gly-Arg-modified polydopamine-coated nanoparticles for dual-targeting therapy of brain glioma in rats.

    PubMed

    Hu, Jiangang; Zhang, Xiang; Wen, Zuhuang; Tan, Ying; Huang, Ning; Cheng, Si; Zheng, Huzhi; Cheng, Yuan

    2016-11-08

    The blood-brain barrier (BBB) is the major clinical obstacle in the chemotherapeutic management of brain glioma. Here we synthesized a pH-sensitive dual-targeting doxorubicin (DOX) carrier to compromise tumor endothelial cells, enhance BBB transportation, and improve drug accumulation in glioma cells. The drug delivery system was constructed with polydopamine (PDA)-coated mesoporous silica nanoparticles (NPs, MSNs) and the PDA coating was functionalized with Asn-Gly-Arg (NGR), a ligand with specific affinity for cluster of differentiation 13 (CD13). MSN-DOX-PDA-NGR showed a higher intracellular accumulation in primary brain capillary endothelial cells (BCECs) and C6 cells and greater BBB permeability than the non-targeting NPs (MSN-DOX-PDA) did in vitro. Ex vivo and in vivo tests showed that MSN-DOX-PDA-NGR had a higher accumulation in intracranial tumorous tissue than the undecorated NPs did. Furthermore, the antiangiogenesis and antitumor efficacy of MSN-DOX-PDA-NGR were stronger than that of MSN-DOX-PDA. Therefore, these results indicate that the dual-targeting vehicles are potentially useful in brain glioma therapy.

  18. Asn-Gly-Arg-modified polydopamine-coated nanoparticles for dual-targeting therapy of brain glioma in rats

    PubMed Central

    Hu, Jiangang; Zhang, Xiang; Wen, Zuhuang; Tan, Ying; Huang, Ning; Cheng, Si; Zheng, Huzhi; Cheng, Yuan

    2016-01-01

    The blood-brain barrier (BBB) is the major clinical obstacle in the chemotherapeutic management of brain glioma. Here we synthesized a pH-sensitive dual-targeting doxorubicin (DOX) carrier to compromise tumor endothelial cells, enhance BBB transportation, and improve drug accumulation in glioma cells. The drug delivery system was constructed with polydopamine (PDA)-coated mesoporous silica nanoparticles (NPs, MSNs) and the PDA coating was functionalized with Asn-Gly-Arg (NGR), a ligand with specific affinity for cluster of differentiation 13 (CD13). MSN-DOX-PDA-NGR showed a higher intracellular accumulation in primary brain capillary endothelial cells (BCECs) and C6 cells and greater BBB permeability than the non-targeting NPs (MSN-DOX-PDA) did in vitro. Ex vivo and in vivo tests showed that MSN-DOX-PDA-NGR had a higher accumulation in intracranial tumorous tissue than the undecorated NPs did. Furthermore, the antiangiogenesis and antitumor efficacy of MSN-DOX-PDA-NGR were stronger than that of MSN-DOX-PDA. Therefore, these results indicate that the dual-targeting vehicles are potentially useful in brain glioma therapy. PMID:27655664

  19. PEG-b-AGE Polymer Coated Magnetic Nanoparticle Probes with Facile Functionalization and Anti-fouling Properties for Reducing Non-specific Uptake and Improving Biomarker Targeting

    PubMed Central

    Wang, Liya; Huang, Jing; Wu, Hui; Cheng, Guojun; Zhou, Zhengyang; MacDonald, Tobey; Yang, Lily; Mao, Hui

    2015-01-01

    Non-specific surface adsorption of bio-macromolecules (e.g. proteins) on nanoparticles, known as biofouling, and the uptake of nanoparticles by the mononuclear phagocyte system (MPS) and reticuloendothelial system (RES) lead to substantial reduction in the efficiency of target-directed imaging and delivery in biomedical applications of engineered nanomaterials in vitro and in vivo. In this work, a novel copolymer consisting of blocks of poly ethylene glycol and allyl glycidyl ether (PEG-b-AGE) was developed for coating magnetic iron oxide nanoparticles (IONPs) to reduce non-specific protein adhesion that leads to formation of “protein corona” and uptake by macrophages. The facile surface functionalization was demonstrated by using targeting ligands of a small peptide of RGD or a whole protein of transferrin (Tf). The PEG-b-AGE coated IONPs exhibited anti-biofouling properties with significantly reduced protein corona formation and non-specific uptake by macrophages before and after the surface functionalization, thus improving targeting of RGD-conjugated PEG-b-AGE coated IONPs to integrins in U87MG glioblastoma and MDA-MB-231 breast cancer cells that overexpress αvβ3 integrins, and Tf-conjugated PEG-b-AGE coated IONPs to transferrin receptor (TfR) in D556 and Daoy medulloblastoma cancer cells with high overexpression of transferrin receptor, compared to respective control cell lines. Magnetic resonance imaging (MRI) of cancer cells treated with targeted IONPs with or without anti-biofouling PEG-b-AGE coating polymers demonstrated the target specific MRI contrast change using anti-biofouling PEG-b-AGE coated IONP with minimal off-targeted background compared to the IONPs without anti-biofouling coating, promising the highly efficient active targeting of nanoparticle imaging probes and drug delivery systems and potential applications of imaging quantification of targeted biomarkers. PMID:26594360

  20. PEG-b-AGE Polymer Coated Magnetic Nanoparticle Probes with Facile Functionalization and Anti-fouling Properties for Reducing Non-specific Uptake and Improving Biomarker Targeting.

    PubMed

    Li, Yuancheng; Lin, Run; Wang, Liya; Huang, Jing; Wu, Hui; Cheng, Guojun; Zhou, Zhengyang; MacDonald, Tobey; Yang, Lily; Mao, Hui

    2015-05-07

    Non-specific surface adsorption of bio-macromolecules (e.g. proteins) on nanoparticles, known as biofouling, and the uptake of nanoparticles by the mononuclear phagocyte system (MPS) and reticuloendothelial system (RES) lead to substantial reduction in the efficiency of target-directed imaging and delivery in biomedical applications of engineered nanomaterials in vitro and in vivo. In this work, a novel copolymer consisting of blocks of poly ethylene glycol and allyl glycidyl ether (PEG-b-AGE) was developed for coating magnetic iron oxide nanoparticles (IONPs) to reduce non-specific protein adhesion that leads to formation of "protein corona" and uptake by macrophages. The facile surface functionalization was demonstrated by using targeting ligands of a small peptide of RGD or a whole protein of transferrin (Tf). The PEG-b-AGE coated IONPs exhibited anti-biofouling properties with significantly reduced protein corona formation and non-specific uptake by macrophages before and after the surface functionalization, thus improving targeting of RGD-conjugated PEG-b-AGE coated IONPs to integrins in U87MG glioblastoma and MDA-MB-231 breast cancer cells that overexpress αvβ3 integrins, and Tf-conjugated PEG-b-AGE coated IONPs to transferrin receptor (TfR) in D556 and Daoy medulloblastoma cancer cells with high overexpression of transferrin receptor, compared to respective control cell lines. Magnetic resonance imaging (MRI) of cancer cells treated with targeted IONPs with or without anti-biofouling PEG-b-AGE coating polymers demonstrated the target specific MRI contrast change using anti-biofouling PEG-b-AGE coated IONP with minimal off-targeted background compared to the IONPs without anti-biofouling coating, promising the highly efficient active targeting of nanoparticle imaging probes and drug delivery systems and potential applications of imaging quantification of targeted biomarkers.

  1. Doxorubicin loaded PEG-b-poly(4-vinylbenzylphosphonate) coated magnetic iron oxide nanoparticles for targeted drug delivery

    NASA Astrophysics Data System (ADS)

    Hałupka-Bryl, Magdalena; Bednarowicz, Magdalena; Dobosz, Bernadeta; Krzyminiewski, Ryszard; Zalewski, Tomasz; Wereszczyńska, Beata; Nowaczyk, Grzegorz; Jarek, Marcin; Nagasaki, Yukio

    2015-06-01

    Due to their unique physical properties, superparamagnetic iron oxide nanoparticles are increasingly used in medical applications. They are very useful carriers for delivering antitumor drugs in targeted cancer treatment. Magnetic nanoparticles with chemiotherapeutic were synthesized by coprecipitation method followed by coating with biocompatible polymer. The aim of this work is to characterize physical and magnetic properties of synthesized nanoparicles. Characterization was carried out using EPR, HRTEM, X-ray diffraction, SQUID and NMR methods. The present findings show that synthesized nanosystem is promising tool for potential magnetic drug delivery.

  2. Utilizing Functional Genomics Screening to Identify Potentially Novel Drug Targets in Cancer Cell Spheroid Cultures

    PubMed Central

    Morrison, Eamonn; Wai, Patty; Leonidou, Andri; Bland, Philip; Khalique, Saira; Farnie, Gillian; Daley, Frances; Peck, Barrie; Natrajan, Rachael

    2016-01-01

    The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery of the next generation of novel drug targets. It is becoming apparent that more complex models of cancer are required to fully appreciate the contributing factors that drive tumorigenesis in vivo and increase the efficacy of novel therapies that make the transition from pre-clinical models to clinical trials. Here we present a methodology for generating uniform and reproducible tumor spheroids that can be subjected to siRNA functional screening. These spheroids display many characteristics that are found in solid tumors that are not present in traditional two-dimension culture. We show that several commonly used breast cancer cell lines are amenable to this protocol. Furthermore, we provide proof-of-principle data utilizing the breast cancer cell line BT474, confirming their dependency on amplification of the epidermal growth factor receptor HER2 and mutation of phosphatidylinositol-4,5-biphosphate 3-kinase (PIK3CA) when grown as tumor spheroids. Finally, we are able to further investigate and confirm the spatial impact of these dependencies using immunohistochemistry. PMID:28060271

  3. Whole Genome Sequencing Reveals Potential New Targets for Improving Nitrogen Uptake and Utilization in Sorghum bicolor

    PubMed Central

    Massel, Karen; Campbell, Bradley C.; Mace, Emma S.; Tai, Shuaishuai; Tao, Yongfu; Worland, Belinda G.; Jordan, David R.; Botella, Jose R.; Godwin, Ian D.

    2016-01-01

    Nitrogen (N) fertilizers are a major agricultural input where more than 100 million tons are supplied annually. Cereals are particularly inefficient at soil N uptake, where the unrecovered nitrogen causes serious environmental damage. Sorghum bicolor (sorghum) is an important cereal crop, particularly in resource-poor semi-arid regions, and is known to have a high NUE in comparison to other major cereals under limited N conditions. This study provides the first assessment of genetic diversity and signatures of selection across 230 fully sequenced genes putatively involved in the uptake and utilization of N from a diverse panel of sorghum lines. This comprehensive analysis reveals an overall reduction in diversity as a result of domestication and a total of 128 genes displaying signatures of purifying selection, thereby revealing possible gene targets to improve NUE in sorghum and cereals alike. A number of key genes appear to have been involved in selective sweeps, reducing their sequence diversity. The ammonium transporter (AMT) genes generally had low allelic diversity, whereas a substantial number of nitrate/peptide transporter 1 (NRT1/PTR) genes had higher nucleotide diversity in domesticated germplasm. Interestingly, members of the distinct race Guinea margaritiferum contained a number of unique alleles, and along with the wild sorghum species, represent a rich resource of new variation for plant improvement of NUE in sorghum. PMID:27826302

  4. Epitope imprinted polymer coating CdTe quantum dots for specific recognition and direct fluorescent quantification of the target protein bovine serum albumin.

    PubMed

    Yang, Ya-Qiong; He, Xi-Wen; Wang, Yi-Zhi; Li, Wen-You; Zhang, Yu-Kui

    2014-04-15

    A novel epitope molecularly imprinted polymer (EMIP) for specific recognition and direct fluorescent quantification of the target protein bovine serum albumin (BSA) was demonstrated where polymerization was performed on the surface of silica nanospheres embedded CdTe quantum dots (QDs). The synthetic peptide derived from the surface-exposed C-terminus of bovine serum albumin (BSA, residues 599-607) was selected as the template molecule. The resulting EMIP film was able to selectively capture the template peptide and the corresponding target protein BSA via the recognition cavities. Based on the fluorescence quenching, the EMIP-coated QDs (molecular imprinted polymer coating CdTe QDs using epitope as the template) nanospheres were successfully applied to the direct fluorescence quantification of BSA. Compared with BMIP-coated QDs (molecular imprinted polymer coating CdTe QDs using BSA as the template), the imprinting factor and adsorption capacity of EMIP-coated QDs were greatly increased. The prepared EMIP-coated QDs can also discriminate even one mismatched sequences from the original sequences of the epitope of the BSA. The practical analytical performance of the EMIP-coated QDs was examined by evaluating the detection of BSA in the bovine calf serum sample with satisfactory results. In addition, the resulting EMIP-coated QDs nanospheres were also successfully applied to separating BSA from the bovine blood sample. © 2013 Published by Elsevier B.V.

  5. Signal enhancement in electrospray laser desorption/ionization mass spectrometry by using a black oxide-coated metal target and a relatively low laser fluence.

    PubMed

    Kononikhin, Alexey; Huang, Min-Zong; Popov, Igor; Kostyukevich, Yury; Kukaev, Evgeny; Boldyrev, Alexey; Spasskiy, Alexander; Leypunskiy, Ilya; Shiea, Jentaie; Nikolaev, Eugene

    2013-01-01

    The electrospray Laser desorption/ionization (ELDI) method is actively used for direct sample analysis and ambient mass spectrometry imaging. The optimizing of Laser desorption conditions is essential for this technology. In this work, we propose using a metal target with a black oxide (Fe3O4) coating to increase the signal in ELDI-MS for peptides and small proteins. The experiments were performed on an LTQ-FT mass spectrometer equipped with a home-made ELDI ion source. A cutter blade with black oxide coating was used as a target. A nitrogen laser was used with the following parameters: 337 nm, pulse duration 4ns, repetition rate 10 Hz, fluence to approximately 700 Jm(-2). More than a five times signal increase was observed for a substance P peptide when a coated and a non-coated metal target were compared. No ion signal was observed for proteins if the same fluence and the standard stainless steel target were used. With the assistance of the Fe3O4 coated metal target and a relatively low laser fluence < or =700 Jm(-2)), proteins such as insulin, ubiquitin and myoglobin were successfully ionized. It was demonstrated that the Fe3O4-coated metal target can be used efficiently to assist laser desorption and thus significantly increase the analyte signal in ELDI-MS. A relatively low laser fluence (< or = 700 Jm(-2)) was enough to desorb peptides and proteins (up to 17 kDal with the assistance of the Fe3O4-coated metal target under ambient conditions.

  6. Calcium Binding-Mediated Sustained Release of Minocycline from Hydrophilic Multilayer Coatings Targeting Infection and Inflammation

    PubMed Central

    Zhang, Zhiling; Nix, Camilla A.; Ercan, Utku K.; Gerstenhaber, Jonathan A.; Joshi, Suresh G.; Zhong, Yinghui

    2014-01-01

    Infection and inflammation are common complications that seriously affect the functionality and longevity of implanted medical implants. Systemic administration of antibiotics and anti-inflammatory drugs often cannot achieve sufficient local concentration to be effective, and elicits serious side effects. Local delivery of therapeutics from drug-eluting coatings presents a promising solution. However, hydrophobic and thick coatings are commonly used to ensure sufficient drug loading and sustained release, which may limit tissue integration and tissue device communications. A calcium-mediated drug delivery mechanism was developed and characterized in this study. This novel mechanism allows controlled, sustained release of minocycline, an effective antibiotic and anti-inflammatory drug, from nanoscale thin hydrophilic polyelectrolyte multilayers for over 35 days at physiologically relevant concentrations. pH-responsive minocycline release was observed as the chelation between minocycline and Ca2+ is less stable at acidic pH, enabling ‘smart’ drug delivery in response to infection and/or inflammation-induced tissue acidosis. The release kinetics of minocycline can be controlled by varying initial loading, Ca2+ concentration, and Ca2+ incorporation into different layers, enabling facile development of implant coatings with versatile release kinetics. This drug delivery platform can potentially be used for releasing any drug that has high Ca2+ binding affinity, enabling its use in a variety of biomedical applications. PMID:24409292

  7. Biosynthesis, targeting and processing of oleosin-like proteins, which are major pollen coat components in Brassica napus.

    PubMed

    Murphy, D J; Ross, J H

    1998-01-01

    The purpose of this study is to characterise the biosynthesis, targeting and processing of some of the major protein components of the pollen coat, or tryphine, of Brassica napus. The authors have N-terminally sequenced 11 of the most abundant pollen coat polypeptides, and nine of these sequences correspond to proteolytically cleaved products of seven oleosin-like genes, i.e. Oln B;1 to Oln B;6 and Oln B;11. The Oln B;11 gene product is co- or post-translationally targeted in vitro to canine microsomal membranes. This implies that the oleosin-like protein is targeted to the endoplasmic reticulum in tapetal cells in vivo. Affinity-purified antibodies raised against a 20-residue domain of Oln B;3 and B;4 gene products cross-reacted with full-length proteins of 45-48 kDa in early developing (< 2 mm to 5 mm) buds and anthers, but recognised truncated proteins of 32-38 kDa at later (4 mm to 7 mm) stages of development. The 45-48 kDa immunoreactive proteins were associated with a floating lipid body fraction obtained from a tapetal/locular fluid extract from maturing anthers and a major 48 kDa polypeptide from this fraction was confirmed by N-terminal sequencing to be a full length product of the Oln B;3 gene. Quantitative immunocytochemical studies showed that the full length 45-48 kDa oleosin-like proteins were specifically localised in the interior of tapetal cytoplasmic lipid bodies where they were associated with a regular hexagonal-like fibrous reticulum. No significant labelling of elaioplasts was observed. The same antibodies specifically labelled 32-38 kDa oleosin-like proteins on the extracellular pollen coat of maturing pollen grains. These results demonstrate for the first time that many of the major pollen coat proteins are derived from an endoproteolytic cleavage of precursor oleosin-like proteins that originally accumulate within the large cytoplasmic lipid bodies of tapetal cells.

  8. Preferential Cancer Cell Self-Recognition and Tumor Self-Targeting by Coating Nanoparticles with Homotypic Cancer Cell Membranes.

    PubMed

    Zhu, Jing-Yi; Zheng, Di-Wei; Zhang, Ming-Kang; Yu, Wu-Yang; Qiu, Wen-Xiu; Hu, Jing-Jing; Feng, Jun; Zhang, Xian-Zheng

    2016-09-14

    The ultimate goal in cancer therapy and diagnosis is to achieve highly specific targeting to cancer cells. Coated with the source cancer cell membrane specifically derived from the homologous tumors, the nanoparticles are identified with the self-recognition internalization by the source cancer cell lines in vitro and the highly tumor-selective targeting "homing" to the homologous tumor in vivo even in the competition of another heterologous tumor. As the result, MNP@DOX@CCCM nanovehicle showed strong potency for tumor treatment in vivo and the MR imaging. This bioinspired strategy shows great potential for precise therapy/diagnosis of various tumors merely by adjusting the cell membrane source accordingly on the nanoparticle surface.

  9. Temperature-sensitive polymer-coated magnetic nanoparticles as a potential drug delivery system for targeted therapy of thyroid cancer.

    PubMed

    Koppolu, Bhanuprasanth; Bhavsar, Zarna; Wadajkar, Aniket S; Nattama, Sivaniarvindpriya; Rahimi, Maham; Nwariaku, Fiemu; Nguyen, Kytai T

    2012-12-01

    The objective of this work was to develop and investigate temperature-sensitive poly(N-isopropylacrylamide-acrylamide-allylamine)-coated iron oxide magnetic nanoparticles (TPMNPs) as possible targeted drug carriers for treatments of advanced thyroid cancer (ATC). These nanoparticles were prepared by free radical polymerization of monomers on the surface of silane-coupled iron oxide nanoparticles. In vitro studies demonstrated that TPMNPs were cytocompatible and effectively taken up by cancer cells in a dose-dependent manner. An external magnetic field significantly increased nanoparticle uptake, especially when cells were exposed to physiological flow conditions. Drug loading and release studies using doxorubicin confirmed the temperature-responsive release of drugs from nanoparticles. In addition, doxorubicin-loaded nanoparticles significantly killed ATC cells when compared to free doxorubicin. The in vitro results indicate that TPMNPs have potential as targeted and controlled drug carriers for thyroid cancer treatment.

  10. A dual mode targeting probe for distinguishing HER2-positive breast cancer cells using silica-coated fluorescent magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Li, Jia; An, Yan-Li; Zang, Feng-Chao; Zong, Shen-Fei; Cui, Yi-Ping; Teng, Gao-Jun

    2013-10-01

    We report a composite nanoprobe based on silica-coated magnetic nanoparticles (NPs) for distinguishing breast cancers at different HER2 statuses. The nanoprobe has a core-shell structure, with Fe3O4 NPs as the magnetic core and dye-embedded silica as the fluorescent shell, whose average size is about 150 nm. Besides, the outmost surfaces of the probes were modified with specific antibodies to endow the probe with a targeting ability. With such a structure, the nanoprobe can accomplish dual mode targeting of human breast cancer cells based on fluorescence and magnetic resonance imaging (MRI). In the experiments, three human breast cancer cell lines were used to test the targeting ability of the nanoprobe. Specifically, SKBR3 cells with a high HER2 expression level were used as the model target cells, while MCF7 cells with a lower HER2 expression levels and HER2-negative MDA-MB-231 cells were used as the controls. Both the fluorescence and MRI imaging results confirmed that the nanoprobe can distinguish three cancer cell lines with different HER2 expression levels. With the dual mode imaging and specific targeting properties, we anticipate that the presented nanoprobe may have a great potential in the diagnosis and treatment of cancerous diseases.

  11. A Multifunctional Platform for Tumor Angiogenesis-Targeted Chemo-Thermal Therapy Using Polydopamine-Coated Gold Nanorods.

    PubMed

    Zhang, Lu; Su, Huilan; Cai, Jiali; Cheng, Dengfeng; Ma, Yongjie; Zhang, Jianping; Zhou, Chuanqing; Liu, Shiyuan; Shi, Hongcheng; Zhang, Yingjian; Zhang, Chunfu

    2016-11-22

    Image-guided combined chemo-thermal therapy assists in optimizing treatment time, enhancing therapeutic efficiency, and circumventing side effects. In the present study, we developed a chemo-photothermal theranostic platform based on polydopamine (PDA)-coated gold nanorods (GNRs). The PDA coating was thin; however, it significantly suppressed the cytotoxicity of the cetyltrimethylammonium bromide template and allowed high cisplatin loading efficiency, arginine-glycine-aspartic acid (RGD) peptide (c(RGDyC)) conjugation, and chelator-free iodine-125 labeling (RGD-(125)IPt-PDA@GNRs). While loaded cisplatin was released in a pH-sensitive manner, labeled (125)I was outstandingly stable under biological conditions. RGD-(125)IPt-PDA@GNRs had a high specificity for αvβ3 integrin, and consequently, they could selectively accumulate in tumors, as revealed by single photon emission computed tomography/CT imaging, and in target tumor angiogenic vessels, as shown by high-resolution photoacoustic imaging. As RGD-(125)IPt-PDA@GNRs targets tumor angiogenesis, it is a highly potent tumor therapy. Combined chemo-photothermal therapy with probes could thoroughly ablate tumors and inhibit tumor relapse via a synergistic antitumor effect. Our studies demonstrated that RGD-(125)IPt-PDA@GNRs is a robust platform for image-guided, chemo-thermal tumor therapy with outstanding synergistic tumor killing and relapse inhibition effects.

  12. A haemophilia disease management programme targeting cost and utilization of specialty pharmaceuticals.

    PubMed

    Duncan, N; Roberson, C; Lail, A; Donfield, S; Shapiro, A

    2014-07-01

    The high cost of clotting factor concentrate (CFC) used to treat haemophilia and von Willebrand disease (VWD) attracts health plans' attention for cost management strategies such as disease management programmes (DMPs). In 2004, Indiana's high risk insurance health plan, the Indiana Comprehensive Health Insurance Association, in partnership with the Indiana Hemophilia and Thrombosis Center developed and implemented a DMP for beneficiaries with bleeding disorders. This report evaluates the effectiveness of the DMP 5 years post implementation, with specific emphasis on the cost of CFC and other medical expenditures by severity of disease. A pre/post analysis was used. The main evaluation measures were total cost, total outpatient CFC IU dispensed and adjusted total outpatient CFC cost. Summary statistics and mean and median plots were calculated. Overall, 1000 non-parametric bootstrap replicates were created and percentile confidence limits for 95% confidence intervals (CI) are reported. Mean emergency department (ED) visits and mean and median duration of hospitalizations are also reported. The DMP was associated with a significant decrease in mean annualized total cost including decreased CFC utilization and cost in most years in the overall group, and specifically in patients with severe haemophilia. Patients with mild and moderate haemophilia contributed little to overall programme expenditures. This specialty health care provider-administered DMP exemplifies the success of targeted interventions developed and implemented through a health care facility expert in the disease state to curb the cost of specialty pharmaceuticals in conditions when their expenditures represent a significant portion of total annual costs of care. © 2014 John Wiley & Sons Ltd.

  13. Degree of target utilization influences the location of movement endpoint distributions.

    PubMed

    Slifkin, Andrew B; Eder, Jeffrey R

    2017-03-01

    According to dominant theories of motor control, speed and accuracy are optimized when, on the average, movement endpoints are located at the target center and when the variability of the movement endpoint distributions is matched to the width of the target (viz., Meyer, Abrams, Kornblum, Wright, & Smith, 1988). The current study tested those predictions. According to the speed-accuracy trade-off, expanding the range of variability to the amount permitted by the limits of the target boundaries allows for maximization of movement speed while centering the distribution on the target center prevents movement errors that would have occurred had the distribution been off center. Here, participants (N=20) were required to generate 100 consecutive targeted hand movements under each of 15 unique conditions: There were three movement amplitude requirements (80, 160, 320mm) and within each there were five target widths (5, 10, 20, 40, 80mm). According to the results, it was only at the smaller target widths (5, 10mm) that movement endpoint distributions were centered on the target center and the range of movement endpoint variability matched the range specified by the target boundaries. As target width increased (20, 40, 80mm), participants increasingly undershot the target center and the range of movement endpoint variability increasingly underestimated the variability permitted by the target region. The degree of target center undershooting was strongly predicted by the difference between the size of the target and the amount of movement endpoint variability, i.e., the amount of unused space in the target. The results suggest that participants have precise knowledge of their variability relative to that permitted by the target, and they use that knowledge to systematically reduce the travel distance to targets. The reduction in travel distance across the larger target widths might have resulted in greater cost savings than those associated with increases in speed

  14. UTILIZING SHELLFISH RESPONSES TO SET TARGET WATER QUALITY CONDITIONS FOR THE RESTORATION OF OYSTER REEFS IN THE CALOOSAHATCHEE ESTUARY, FLORIDA.

    EPA Science Inventory

    Volety, Aswani K., S.G. Tolley and James T. Winstead. 2002. Utilizing Shellfish Responses to Set Target Water Quality Conditions for the Restoration of Oyster Reefs in the Caloosahatchee Estuary, Florida. Presented at the International Workshop on Restoration of Benthic Invertebr...

  15. UTILIZING SHELLFISH RESPONSES TO SET TARGET WATER QUALITY CONDITIONS FOR THE RESTORATION OF OYSTER REEFS IN THE CALOOSAHATCHEE ESTUARY, FLORIDA.

    EPA Science Inventory

    Volety, Aswani K., S.G. Tolley and James T. Winstead. 2002. Utilizing Shellfish Responses to Set Target Water Quality Conditions for the Restoration of Oyster Reefs in the Caloosahatchee Estuary, Florida. Presented at the International Workshop on Restoration of Benthic Invertebr...

  16. A SERS and fluorescence dual mode cancer cell targeting probe based on silica coated Au@Ag core-shell nanorods.

    PubMed

    Zong, Shenfei; Wang, Zhuyuan; Yang, Jing; Wang, Chunlei; Xu, Shuhong; Cui, Yiping

    2012-08-15

    We report a dual mode cancer cell targeting probe based on CdTe quantum dots (QDs) conjugated, silica coated Au@Ag core-shell nanorods (Au@Ag NRs), which can generate both surface enhanced Raman scattering (SERS) and fluorescence signals. In such a probe, folic acid (FA) is used as a targeting ligand for folate receptors (FRs) overexpressed cancer cells. To synthesize the probe, Au@Ag NRs were first prepared to serve as the SERS substrates by coating an Ag shell on the gold nanorods. Then the Au@Ag NRs were labeled with 4-mercaptobenzoic acid (4MBA) to generate SERS signals, followed by being coated with a silica shell through a modified Stöber method. Finally, CdTe QDs and FA were conjugated to the silica coated Au@Ag NRs by the carbodiimide chemistry to yield fluorescence and the targeting ability, respectively. To validate the targeting capability of the probe, in vitro experiments were conducted, using HeLa cells with overexpressed FRs as the model target cells and MRC-5 cells with a low folate receptor expression level as the negative control. Both the fluorescence imaging and the SERS mapping results confirmed that the proposed probe can be used as an efficient cancer cell targeting agent. This kind of multifunctional probe has great potential in the diagnosis and therapeutics of cancerous diseases due to its specific targeting and multiplex imaging abilities, especially in the simultaneous tracking of multiple components in a hybrid bio-system.

  17. Distinct regions at the N-terminus of the Cucumber necrosis virus coat protein target chloroplasts and mitochondria.

    PubMed

    Hui, Elizabeth; Xiang, Yu; Rochon, D'Ann

    2010-10-01

    Cucumber necrosis virus (CNV) is a spherical virus consisting of 180 identical coat protein (CP) subunits. The N-terminus of the CP subunit contains a 58aa RNA binding (R) domain and a 34aa arm that connects the R domain to the shell. These regions are known to play critical roles in virus assembly and disassembly. It has recently been shown that a region encompassing the arm can function as a chloroplast transit peptide (TP) in infected plants and that targeting may represent a means for virus particle disassembly. In this study, we further delineate the TP region and show that a 22aa sequence at the N-terminus of the shell enhances chloroplast targeting. We also demonstrate that R domain specifically co-localizes with mitochondria in agroinfiltrated plants. Deletion analyses show that the N-terminal 39 amino acids of the R domain are sufficient for mitochondrial targeting and that this region contains features typical of mitochondrial presequences. The R/arm region is found to be dually targeted to mitochondria and chloroplasts suggesting that this region of the CP plays a critical role in determining the fate of CP during the infection process. (c) 2010. Published by Elsevier B.V. All rights reserved.

  18. CXCR4-targeted lipid-coated PLGA nanoparticles deliver sorafenib and overcome acquired drug resistance in liver cancer.

    PubMed

    Gao, Dong-Yu; Lin, Ts-Ting; Sung, Yun-Chieh; Liu, Ya Chi; Chiang, Wen-Hsuan; Chang, Chih-Chun; Liu, Jia-Yu; Chen, Yunching

    2015-10-01

    Sorafenib, a multikinase inhibitor, has been used as an anti-angiogenic agent against highly vascular hepatocellular carcinoma (HCC) - yet associated with only moderate therapeutic effect and the high incidence of HCC recurrence. We have shown intratumoral hypoxia induced by sorafenib activated C-X-C receptor type 4 (CXCR4)/stromal-derived factor 1α (SDF1α) axis, resulting in polarization toward a tumor-promoting microenvironment and resistance to anti-angiogenic therapy in HCC. Herein, we formulated sorafenib in CXCR4-targeted lipid-coated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) modified with a CXCR4 antagonist, AMD3100 to systemically deliver sorafenib into HCC and sensitize HCC to sorafenib treatment. We demonstrated that CXCR4-targeted NPs efficiently delivered sorafenib into HCCs and human umbilical vein endothelial cells (HUVECs) to achieve cytotoxicity and anti-angiogenic effect in vitro and in vivo. Despite the increased expression of SDF1α upon the persistent hypoxia induced by sorafenib-loaded CXCR4-targeted NPs, AMD3100 attached to the NPs can block CXCR4/SDF1α, leading to the reduced infiltration of tumor-associated macrophages, enhanced anti-angiogenic effect, a delay in tumor progression and increased overall survival in the orthotopic HCC model compared with other control groups. In conclusion, our results highlight the clinical potential of CXCR4-targeted NPs for delivering sorafenib and overcoming acquired drug resistance in liver cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Biocompatible mesoporous silica-coated superparamagnetic manganese ferrite nanoparticles for targeted drug delivery and MR imaging applications.

    PubMed

    Sahoo, Banalata; Devi, K Sanjana P; Dutta, Sujan; Maiti, Tapas K; Pramanik, Panchanan; Dhara, Dibakar

    2014-10-01

    Multifunctional mesoporous silica-coated superparamagnetic manganese ferrite (MnFe2O4) nanoparticles (M-MSN) were synthesized and evaluated for targeted drug delivery and magnetic resonance imaging (MRI) applications. MnFe2O4 nanoparticles were prepared by solvothermal route and were silica-coated by surface silylation using sol-gel reactions. Subsequently, silylation was done using (3-aminopropyl)triethoxysilane in presence of a surfactant (CTAB), followed by selective etching of the surfactant molecules that resulted in amine-functionalized superparamagnetic nanoparticles (NH2-MSN). Further modification of the surface of the NH2-MSN with targeting (folate) or fluorescent (RITC) molecules resulted in M-MSN. The formation of the M-MSN was proved by several characterization techniques viz. XRD, XPS, HRTEM, FESEM, VSM, BET surface area measurement, FTIR, and UV-Vis spectroscopy. The M-MSN were loaded with anticancer drug Doxorubicin and the efficacy of the DOX loaded M-MSN was evaluated through in vitro cytotoxicity, fluorescence microscopy, and apoptosis studies. The in vivo biocompatibility of the M-MSN was demonstrated in a mice-model system. Moreover, the M-MSN also acted as superior MRI contrast agent owing to a high magnetization value as well as superparamagnetic behavior at room temperature. These folate-conjugated nanoparticles (FA-MSN) exhibited stronger T2-weighted MRI contrast towards HeLa cells as compared to the nanoparticles without folate conjugation, justifying their potential importance in MRI based diagnosis of cancer. Such M-MSN with a magnetic core required for MRI imaging, a porous shell for carrying drug molecules, a targeting moeity for cancer cell specificity and a fluorescent molecule for imaging, all integrated into a single system, may potentially serve as an excellent material in biomedical applications. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Nonfouling NTA-PEG-Based TEM Grid Coatings for Selective Capture of Histidine-Tagged Protein Targets from Cell Lysates.

    PubMed

    Benjamin, Christopher J; Wright, Kyle J; Hyun, Seok-Hee; Krynski, Kyle; Yu, Guimei; Bajaj, Ruchika; Guo, Fei; Stauffacher, Cynthia V; Jiang, Wen; Thompson, David H

    2016-01-19

    We report the preparation and performance of TEM grids bearing stabilized nonfouling lipid monolayer coatings. These films contain NTA capture ligands of controllable areal density at the distal end of a flexible poly(ethylene glycol) 2000 (PEG2000) spacer to avoid preferred orientation of surface-bound histidine-tagged (His-tag) protein targets. Langmuir-Schaefer deposition at 30 mN/m of mixed monolayers containing two novel synthetic lipids-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[(5-amido-1-carboxypentyl)iminodiacetic acid]polyethylene glycolamide 2000) (NTA-PEG2000-DSPE) and 1,2-(tricosa-10',12'-diynoyl)-sn-glycero-3-phosphoethanolamine-N-(methoxypolyethylene glycolamide 350) (mPEG350-DTPE)-in 1:99 and 5:95 molar ratios prior to treatment with a 5 min, 254 nm light exposure was used for grid fabrication. These conditions were designed to limit nonspecific protein adsorption onto the stabilized lipid coating by favoring the formation of a mPEG350 brush layer below a flexible, mushroom conformation of NTA-PEG2000 at low surface density to enable specific immobilization and random orientation of the protein target on the EM grid. These grids were then used to capture His6-T7 bacteriophage and RplL from cell lysates, as well as purified His8-green fluorescent protein (GFP) and nanodisc solubilized maltose transporter, His6-MalFGK2. Our findings indicate that TEM grid supported, polymerized NTA lipid monolayers are capable of capturing His-tag protein targets in a manner that controls their areal densities, while efficiently blocking nonspecific adsorption and limiting film degradation, even upon prolonged detergent exposure.

  1. Brain-targeted delivery of docetaxel by glutathione-coated nanoparticles for brain cancer.

    PubMed

    Grover, Aditya; Hirani, Anjali; Pathak, Yashwant; Sutariya, Vijaykumar

    2014-12-01

    Gliomas are some of the most aggressive types of cancers but the blood-brain barrier acts as an obstacle to therapeutic intervention in brain-related diseases. The blood-brain barrier blocks the permeation of potentially toxic compounds into neural tissue through the interactions of brain endothelial cells with glial cells (astrocytes and pericytes) which induce the formation of tight junctions in endothelial cells lining the blood capillaries. In the present study, we characterize a glutathione-coated docetaxel-loaded PEG-PLGA nanoparticle, show its in vitro drug release data along with cytotoxicity data in C6 and RG2 cells, and investigate its trans-blood-brain barrier permeation through the establishment of a Transwell cellular co-culture. We show that the docetaxel-loaded nanoparticle's size enables its trans-blood-brain barrier permeation; the nanoparticle exhibits a steady, sustained release of docetaxel; the drug is able to induce cell death in glioma models; and the glutathione-coated nanoparticle is able to permeate through the Transwell in vitro blood-brain barrier model.

  2. Polyethylene glycol modified, cross-linked starch-coated iron oxide nanoparticles for enhanced magnetic tumor targeting.

    PubMed

    Cole, Adam J; David, Allan E; Wang, Jianxin; Galbán, Craig J; Hill, Hannah L; Yang, Victor C

    2011-03-01

    While successful magnetic tumor targeting of iron oxide nanoparticles has been achieved in a number of models, the rapid blood clearance of magnetically suitable particles by the reticuloendothelial system (RES) limits their availability for targeting. This work aimed to develop a long-circulating magnetic iron oxide nanoparticle (MNP) platform capable of sustained tumor exposure via the circulation and, thus, potentially enhanced magnetic tumor targeting. Aminated, cross-linked starch (DN) and aminosilane (A) coated MNPs were successfully modified with 5 kDa (A5, D5) or 20 kDa (A20, D20) polyethylene glycol (PEG) chains using simple N-Hydroxysuccinimide (NHS) chemistry and characterized. Identical PEG-weight analogues between platforms (A5 & D5, A20 & D20) were similar in size (140-190 nm) and relative PEG labeling (1.5% of surface amines - A5/D5, 0.4% - A20/D20), with all PEG-MNPs possessing magnetization properties suitable for magnetic targeting. Candidate PEG-MNPs were studied in RES simulations in vitro to predict long-circulating character. D5 and D20 performed best showing sustained size stability in cell culture medium at 37 °C and 7 (D20) to 10 (D5) fold less uptake in RAW264.7 macrophages when compared to previously targeted, unmodified starch MNPs (D). Observations in vitro were validated in vivo, with D5 (7.29 h) and D20 (11.75 h) showing much longer half-lives than D (0.12 h). Improved plasma stability enhanced tumor MNP exposure 100 (D5) to 150 (D20) fold as measured by plasma AUC(0-∞). Sustained tumor exposure over 24 h was visually confirmed in a 9L-glioma rat model (12 mg Fe/kg) using magnetic resonance imaging (MRI). Findings indicate that a polyethylene glycol modified, cross-linked starch-coated MNP is a promising platform for enhanced magnetic tumor targeting, warranting further study in tumor models.

  3. Enhancement of osseointegration by direct coating of rhBMP-2 on target-ion induced plasma sputtering treated SLA surface for dental application.

    PubMed

    Kim, Sungwon; Park, Cheonil; Moon, Byeong-Seok; Kim, Hyoun-Ee; Jang, Tae-Sik

    2016-11-23

    Owing to the excellent bioactive properties of recombinant human bone morphogenetic proteins (rhBMPs), dentistry considers them as a fascinating adjuvant alternative for enhancing bone regeneration and bone-to-implant junction in the early implantation stages. However, stable loading and delivery efficiency of rhBMPs on the implant surfaces involve major concerns because of the harsh wearing condition under load during implantation. In this study, to achieve successful rhBMP-2 delivery, a nanoporous surface structure is introduced on the sandblasting with large grit and acid-etching (SLA)-treated titanium (Ti) surface via the tantalum (Ta) target-ion induced plasma sputtering (TIPS) technique. Unlike oxidation-induced surface nanoporous fabrications on a Ti surface, TIPS-treated surfaces provide excellent structural unity of the nanoporous structure with the substrate due to their etching-based fabrication mechanism. SLA/TIPS-treated Ti exhibits distinct nanoporous structures on the microscale surface geometry and better hydrophilicity compared with SLA-treated Ti. A sufficiently empty nanoporous surface structure combined with the hydrophilic property of SLA/TIPS-treated Ti facilitates the formation of a thick and uniform coating layer of rhBMP-2 on the surface without any macro- and microcoagulation. Compared with the SLA-treated Ti surface, the amount of coated rhBMP-2 increases up to 63% on the SLA/TIPS-treated Ti surface. As a result, the in vitro pre-osteoblast cell response of the SLA/TIPS-treated Ti surface, especially cell adhesion and differentiation behaviors, improves remarkably. A bone-regenerating direct comparison between the rhBMP-2-coated SLA-treated and SLA/TIPS-treated Ti is conducted on a defective dog mandible model. After 8 weeks of implantation surgery, SLA/TIPS-treated Ti with rhBMP-2 exhibits a better degree of contact area for the implanted bone, which mineralizes new bones around the implant. Quantitative results of bone-in-contact ratio

  4. Protection efficacy of gloves against components of the solvent in a sprayed isocyanate coating utilizing a reciprocating permeation panel.

    PubMed

    Ceballos, Diana M; Reeb-Whitaker, Carolyn; Sasakura, Miyoko; Dills, Russell; Yost, Michael G

    2015-04-01

    Determine protection effectiveness of 5-mil natural rubber latex (0.13-mm), 5-mil nitrile rubber (0.13-mm), and 13-mil butyl rubber (0.33-mm) glove materials against solvents present in a commonly used automotive clear coat formulation using a novel permeation panel. The latex and nitrile gloves were the type commonly used by local autobody spray painters. Glove materials were tested by spraying an automotive clear coat onto an automated reciprocating permeation panel (permeation panel II). Temperature, relative humidity, and spray conditions were controlled to optimize clear coat loading homogeneity as evaluated by gravimetric analysis. Solvent permeation was measured using charcoal cloth analyzed by the National Institute for Occupational Safety and Health 1501 method. Natural rubber latex allowed 3-5 times the permeation of solvents relative to nitrile rubber for all 10 solvents evaluated: ethyl benzene, 2-heptanone, 1-methoxy-2-propyl acetate, o-xylene, m-xylene, p-xylene, n-butyl acetate, methyl isobutyl ketone, petroleum distillates, and toluene. There is a distinct behavior in solvent permeation before and after the coating dry time. Solvent permeation increased steadily before coating dry time and remained fairly constant after coating dry time. Butyl was not permeated by any of the solvents under the conditions tested. Commonly used 5-mil thick (0.13-mm) latex and nitrile gloves were ineffective barriers to solvents found in a commonly used clear coat formulation. Conversely, 13-mil (0.33-mm) butyl gloves were found to be protective against all solvents in the clear coat formulation. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  5. Intact cell/intact spore mass spectrometry (IC/ISMS) on polymer-based, nano-coated disposable targets.

    PubMed

    Bugovsky, Stefan; Winkler, Wolfgang; Balika, Werner; Koranda, Manfred; Allmaier, Günter

    2014-01-01

    Identification and differentiation of microorganisms has and still is a long arduous task, involving culturing of the organism in question on different growth media. This procedure, which is still commonly applied, is an established method, but takes a lot of time, up to several days or even longer. It has thus been a great achievement when other analytical tools like matrix-assisted laser desorption/ionization (MALDI) mass spectrometry were introduced for faster analysis based on the surface protein pattern. Differentiation and identification of human pathogens as well as plant/animal pathogens is of increasing importance in medical care (e.g. infection, sepsis, and antibiotics resistance), biotechnology, food sciences and detection of biological warfare agents. A distinction between microorganisms on the species and strain level was made by comparing peptide/protein profiles to patterns already stored in databases. These profiles and patterns were obtained from the surface of vegetative forms of microorganisms or even their spores by MALDI MS. Thus, an unknown sample can be compared against a database of known pathogens or microorganisms of interest. To benefit from newly available, metal-based disposable microscope-slide format MALDI targets that promise a clean and even surface at a fraction of the cost from full metal targets or MTP (microtiter plate) format targets, IC/ISMS analysis was performed on these and the data evaluated. Various types of bacteria as well as fungal spores were identified unambiguously on this disposable new type of metal nano-coated targets. The method even allowed differentiation between strains of the same species. The results were compared with those gained from using full metal standard targets and found to be equal or even better in several aspects, making the use of disposable MALDI targets a viable option for use in IC/ISMS, especially e.g. for large sample throughput and highly pathogenic species.

  6. Polyacrylic acid-coated iron oxide nanoparticles for targeting drug resistance in mycobacteria.

    PubMed

    Padwal, Priyanka; Bandyopadhyaya, Rajdip; Mehra, Sarika

    2014-12-23

    The emergence of drug resistance is a major problem faced in current tuberculosis (TB) therapy, representing a global health concern. Mycobacterium is naturally resistant to most drugs due to export of the latter outside bacterial cells by active efflux pumps, resulting in a low intracellular drug concentration. Thus, development of agents that can enhance the effectiveness of drugs used in TB treatment and bypass the efflux mechanism is crucial. In this study, we present a new nanoparticle-based strategy for enhancing the efficacy of existing drugs. To that end, we have developed poly(acrylic acid) (PAA)-coated iron oxide (magnetite) nanoparticles (PAA-MNPs) as efflux inhibitors and used it together with rifampicin (a first line anti-TB drug) on Mycobacterium smegmatis. PAA-MNPs of mean diameter 9 nm interact with bacterial cells via surface attachment and are then internalized by cells. Although PAA-MNP alone does not inhibit cell growth, treatment of cells with a combination of PAA-MNP and rifampicin exhibits a synergistic 4-fold-higher growth inhibition compared to rifampicin alone. This is because the combination of PAA-MNP and rifampicin results in up to a 3-fold-increased accumulation of rifampicin inside the cells. This enhanced intracellular drug concentration has been explained by real-time transport studies on a common efflux pump substrate, ethidium bromide (EtBr). It is seen that PAA-MNP increases the accumulation of EtBr significantly and also minimizes the EtBr efflux in direct proportion to the PAA-MNP concentration. Our results thus illustrate that the addition of PAA-MNP with rifampicin may bypass the innate drug resistance mechanism of M. smegmatis. This generic strategy is also found to be successful for other anti-TB drugs, such as isoniazid and fluoroquinolones (e.g., norfloxacin), only when stabilized, coated nanoparticles (such as PAA-MNP) are used, not PAA or MNP alone. We hence establish coated nanoparticles as a new class of efflux

  7. Using shape effects to target antibody-coated nanoparticles to lung and brain endothelium

    PubMed Central

    Kolhar, Poornima; Anselmo, Aaron C.; Gupta, Vivek; Pant, Kapil; Prabhakarpandian, Balabhaskar; Ruoslahti, Erkki; Mitragotri, Samir

    2013-01-01

    Vascular endothelium offers a variety of therapeutic targets for the treatment of cancer, cardiovascular diseases, inflammation, and oxidative stress. Significant research has been focused on developing agents to target the endothelium in diseased tissues. This includes identification of antibodies against adhesion molecules and neovascular expression markers or peptides discovered using phage display. Such targeting molecules also have been used to deliver nanoparticles to the endothelium of the diseased tissue. Here we report, based on in vitro and in vivo studies, that the specificity of endothelial targeting can be enhanced further by engineering the shape of ligand-displaying nanoparticles. In vitro studies performed using microfluidic systems that mimic the vasculature (synthetic microvascular networks) showed that rod-shaped nanoparticles exhibit higher specific and lower nonspecific accumulation under flow at the target compared with their spherical counterparts. Mathematical modeling of particle–surface interactions suggests that the higher avidity and specificity of nanorods originate from the balance of polyvalent interactions that favor adhesion and entropic losses as well as shear-induced detachment that reduce binding. In vivo experiments in mice confirmed that shape-induced enhancement of vascular targeting is also observed under physiological conditions in lungs and brain for nanoparticles displaying anti–intracellular adhesion molecule 1 and anti-transferrin receptor antibodies. PMID:23754411

  8. Gradient nanostructured coatings obtained by magnetron sputtering of a multiphase AlN-TiB2-TiSi2 target

    NASA Astrophysics Data System (ADS)

    Pogrebnjak, A. D.; Pshyk, A. V.; Coy, E.; Zaleski, K.; Peplinska, B.; Nowaczyk, G.; Kupchishin, A. I.; Beresnev, V. M.; Kassenova, L. G.; Kravchenko, Ya. O.

    2016-10-01

    The preparation and analysis of gradient nanostructured coatings obtained by the method of the magnetron sputtering of a multiphase composite AlN-TiB2-TiSi2 target are described. The structure and phase and elemental compositions have been investigated by the methods of X-ray diffraction (XRD), atomic force microscopy (AFM), and electron microscopy (SEM and TEM, with energy-dispersive analysis). The mechanical properties of coatings were characterized by the method of nanoindentation. The coating formed consisted of three layers different in the elemental composition and structure, which determined its mechanical properties. The formation of structurally inhomogeneous coating is explained by the fact that the target to be sputtered consisted of three different components (AlN, 50 wt %; TiB2, 35 wt %; TiSi2, 15 wt %) inhomogeneously distributed over the volume of the target. The influence of different processes that occur upon the sputtering of multiphase targets by ions of inert gases on the formation of nanocomposite coatings with a gradient structure is discussed.

  9. Bioactive glass-ceramic coatings prepared by pulsed laser deposition from RKKP targets (sol-gel vs melt-processing route)

    SciTech Connect

    Rau, J.V.; Teghil, R.; Fosca, M.; De Bonis, A.; Cacciotti, I.; Bianco, A.; Albertini, V. Rossi; Caminiti, R.; Ravaglioli, A.

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Bioactive glass-ceramic coatings for bone tissue repair and regeneration. Black-Right-Pointing-Pointer Pulsed Lased Deposition allowed congruent transfer of target composition to coating. Black-Right-Pointing-Pointer Target was prepared by sol-gel process suitable for compositional tailoring. Black-Right-Pointing-Pointer Titanium, widely used for orthopaedics and dental implants, was used as substrate. Black-Right-Pointing-Pointer The physico-chemical properties of the prepared coatings are reported. -- Abstract: The deposition of innovative glass-ceramic composition (i.e. RKKP) coatings by Pulsed Lased Deposition (PLD) technique is reported. RKKP was synthesised following two methodologies: melt-processing and sol-gel, the latter being particularly suitable to tailor the compositional range. The PLD advantage with respect to other deposition techniques is the congruent transfer of the target composition to the coating. The physico-chemical properties of films were investigated by Scanning Electron and Atomic Force Microscopies, Fourier Transform Infrared Spectroscopy, Angular and Energy Dispersive X-ray Diffraction, and Vickers microhardness. The deposition performed at 12 J/cm{sup 2} and 500 Degree-Sign C allows to prepare crystalline films with the composition that replicates rather well that of the initial targets. The 0.6 {mu}m thin melt-processing RKKP films, possessing the hardness of 25 GPa, and the 4.3 {mu}m thick sol-gel films with the hardness of 17 GPa were obtained.

  10. The impact of a conditional cash transfer program on the utilization of non-targeted services: Evidence from Afghanistan.

    PubMed

    Witvorapong, Nopphol; Foshanji, Abo Ismael

    2016-03-01

    While existing research suggests that health-related conditional cash transfer (CCT) programs have positive impacts on the utilization of CCT-targeted health services, little is known as to whether they also influence the utilization of non-targeted health services-defined as general health services for which program participants are not financially motivated. Based on a sample of 6649 households in a CCT program that took place in May 2009-June 2011 in Afghanistan, we evaluate the impact of the receipt of CCTs on the utilization of non-targeted health services both by women, who were direct beneficiaries of the program, and by members of their households. We estimate the outcomes of interest through four probit models, accounting for potential endogeneity of the CCT receipt and dealing with lack of credible exclusion restrictions in different ways. In comparison with the control group, the receipt of CCTs is found to be associated with an increase in the probability of utilizing non-targeted services among household members across regression models. The results are mixed, with regard to the utilization by women, suggesting that there exist non-economic barriers to health care, unique to women, that are not captured by the data. The results confirm the importance of accounting for direct as well as indirect effects in policy evaluation and suggest that future studies investigate more deeply the role of community health workers in removing non-economic barriers for Afghan women and the possibility of introducing an incentive structure to motivate them to contribute more actively to population health in Afghanistan.

  11. Hyaluronic acid-coated solid lipid nanoparticles for targeted delivery of vorinostat to CD44 overexpressing cancer cells.

    PubMed

    Tran, Tuan Hiep; Choi, Ju Yeon; Ramasamy, Thiruganesh; Truong, Duy Hieu; Nguyen, Chien Ngoc; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

    2014-12-19

    Hyaluronic acid (HA)-decorated solid lipid nanoparticles (SLNs) were developed for tumor-targeted delivery of vorinostat (VRS), a histone deacetylase inhibitor. HA, a naturally occurring polysaccharide, which specifically binds to the CD44 receptor, was coated on a cationic lipid core through electrostatic interaction. After the optimization process, HA-coated VRS-loaded SLNs (HA-VRS-SLNs) were spherical, core-shell nanoparticles, with small size (∼100 nm), negative charge (∼-9 mV), and narrow size distribution. In vitro release profile of HA-VRS-SLNs showed a typical bi-phasic pattern. In addition, the intracellular uptake of HA-VRS-SLNs was significantly enhanced in CD44 overexpressing cells, A549 and SCC-7 cells, but reduced when HA-VRS-SLNs were incubated with SCC-7 cells pretreated with HA or MCF-7 cells with low over-expressed CD44. Of particular importance, HA-VRS-SLNs were more cytotoxic than the free drug and VRS-SLNs in A549 and SCC-7 cells. In addition, HA shell provided longer blood circulation and reduced VRS clearance rate in rats, resulting in enhanced higher plasma concentration and bioavailability. These results clearly indicated the potential of the HA-functionalized lipid nanoparticle as a nano-sized drug formulation for chemotherapy.

  12. Dextran-coated iron oxide nanoparticles: a versatile platform for targeted molecular imaging, molecular diagnostics, and therapy.

    PubMed

    Tassa, Carlos; Shaw, Stanley Y; Weissleder, Ralph

    2011-10-18

    Advances in our understanding of the genetic basis of disease susceptibility coupled with prominent successes for molecular targeted therapies have resulted in an emerging strategy of personalized medicine. This approach envisions risk stratification and therapeutic selection based on an individual's genetic makeup and physiologic state (the latter assessed through cellular or molecular phenotypes). Molecularly targeted nanoparticles can play a key role in this vision through noninvasive assessments of molecular processes and specific cell populations in vivo, sensitive molecular diagnostics, and targeted delivery of therapeutics. A superparamagnetic iron oxide nanoparticle with a cross-linked dextran coating, or CLIO, is a powerful and illustrative nanoparticle platform for these applications. These structures and their derivatives support diagnostic imaging by magnetic resonance (MRI), optical, and positron emission tomography (PET) modalities and constitute a versatile platform for conjugation to targeting ligands. A variety of conjugation methods exist to couple the dextran surface to different functional groups; in addition, a robust bioorthogonal [4 + 2] cycloaddition reaction between 1,2,4,5-tetrazene (Tz) and trans-cyclooctene (TCO) can conjugate nanoparticles to targeting ligands or label pretargeted cells. The ready availability of conjugation methods has given rise to the synthesis of libraries of small molecule modified nanoparticles, which can then be screened for nanoparticles with specificity for a specific cell type. Since most nanoparticles display their targeting ligands in a multivalent manner, a detailed understanding of the kinetics and affinity of a nanoparticle's interaction with its target (as determined by surface plasmon resonance) can yield functionally important insights into nanoparticle design. In this Account, we review applications of the CLIO platform in several areas relevant to the mission of personalized medicine. We demonstrate

  13. Polarization utilization in radar target reconstruction: C-wide (Multi-frequency) band relationship of a target's characteristic operators with its unique set of natural eigenfrequencies

    NASA Astrophysics Data System (ADS)

    Boerner, W. M.; Huynen, J. R.; Mathur, N. C.; Foo, B. Y.; Nespor, J. D.

    1983-12-01

    During the tenure of this initiation contract on Polarization Utilization in Radar Target Identification a center of excellence for research in high resolution radar polarimetry was established within the Electromagnetic Imaging Division (EMID), Communications Laboratory (CL), Department of Electrical Engineering and Computer Science (EECS), University of Illinois at Chicago (UIC) with the express purpose of advancing theoretical, computational and experimental methods for radar target detection in clutter; separation of useful target vector signal from noise and clutter; classification of targets and/or clutter; target and/or clutter imaging, as well as target identification. To assist us in this endeavor, the College of Engineering, UIC, initially made available 2,200 sq. ft. laboratory space which now has expanded to 9,000 sq. ft. within SEL-4209/4210/4211 with adjacent side rooms, housing the CL-office, work and laboratory space for 18 research assistants and a DEC-VAX 11/750 and 780 Research Computer Processing System with some peripheral image processing, printing, color-graphics processors which were made available with partial funding from DoD-research offices and need to be further expanded.

  14. Fetoprotein Derived Short Peptide Coated Nanostructured Amphiphilic Surfaces for Targeting Mouse Breast Cancer Cells

    NASA Astrophysics Data System (ADS)

    Brown, Alexandra M.; Miranda-Alarćon, Yoliem S.; Knoll, Grant A.; Santora, Anthony M.; Banerjee, Ipsita A.

    In this work, self-assembled tumor targeting nanostructured surfaces were developed from a newly designed amphiphile by conjugating boc protected isoleucine with 2,2‧ ethylenedioxy bis ethylamine (IED). To target mouse mammary tumor cells, a short peptide sequence derived from the human alpha-fetoprotein (AFP), LSEDKLLACGEG was attached to the self-assembled nanostructures. Tumor targeting and cell proliferation were examined in the presence of nanoscale assemblies. To further obliterate mouse breast tumor cells, the chemotherapeutic drug tamoxifen was then entrapped into the nanoassemblies. Our studies indicated that the targeting systems were able to efficiently encapsulate and release tamoxifen. Cell proliferation studies showed that IED-AFP peptide loaded with tamoxifen decreased the proliferation of breast cancer cells while in the presence of the IED-AFP peptide nanoassemblies alone, the growth was relatively slower. In the presence of human dermal fibroblasts however cell proliferation continued similar to controls. Furthermore, the nanoscale assemblies were found to induce apoptosis in mouse breast cancer cells. To examine live binding interactions, SPR analysis revealed that tamoxifen encapsulated IED-AFP peptide nanoassemblies bound to the breast cancer cells more efficiently compared to unencapsulated assemblies. Thus, we have developed nanoscale assemblies that can specifically bind to and target tumor cells, with increased toxicity in the presence of a chemotherapeutic drug.

  15. Targeted removal of trichlorophenol in water by oleic acid-coated nanoscale palladium/zero-valent iron alginate beads.

    PubMed

    Chang, Jaewon; Woo, Heesoo; Ko, Myoung-Soo; Lee, Jaesang; Lee, Seockheon; Yun, Seong-Taek; Lee, Seunghak

    2015-08-15

    A new material was developed and evaluated for the targeted removal of trichlorophenol (TCP) from among potential interferents which are known to degrade removal activity. To achieve TCP-targeted activity, an alginate bead containing nanoscale palladium/zero-valent iron (Pd/nZVI) was coated with a highly hydrophobic oleic acid layer. The new material (Pd/nZVI-A-O) preferentially sorbed TCP from a mixture of chlorinated phenols into the oleic acid cover layer and subsequently dechlorinated it to phenol. The removal efficacy of TCP by Pd/nZVI-A-O was not affected by co-existing organic substances such as Suwannee River humic acid (SRHA), whereas the material without the oleic acid layer (Pd/nZVI-A) became less effective with increasing SRHA concentration. The inorganic substances nitrate and phosphate significantly reduced the reactivity of Pd/nZVI-A, however, Pd/nZVI-A-O showed similar TCP removal efficacies regardless of the initial inorganic ion concentrations. The influence of bicarbonate on the TCP removal efficacies of both Pd/nZVI-A and Pd/nZVI-A-O was not significant. The findings from this study suggest that Pd/nZVI-A-O, with its targeted, constant reactivity for TCP, would be effective for treating this contaminant in surface water or groundwater containing various competitive substrates.

  16. Self-assembly synthesis, tumor cell targeting, and photothermal capabilities of antibody-coated indocyanine green nanocapsules

    PubMed Central

    Yu, Jie; Javier, David; Yaseen, Mohammad A.; Nitin, Nitin; Richards-Kortum, Rebecca; Anvari, Bahman; Wong, Michael S.

    2010-01-01

    New colloidal materials that can generate heat upon irradiation are being explored for photothermal therapy as a minimally invasive approach to cancer treatment. The near-infrared dye indocyanine green (ICG) could serve as a basis for such a material, but its encapsulation and subsequent use is very difficult to carry out. We report the three-step room-temperature synthesis of ~120-nm capsules loaded with ICG within salt-crosslinked polyallylamine aggregates, and coated with anti-epidermal growth factor receptor (anti-EGFR) antibodies for tumor cell targeting capability. We studied the synthesis conditions such as temperature and water dilution to control the capsule size and characterized the size distribution via dynamic light scattering and scanning electron microscopy. We further studied the specificity of tumor cell targeting using three carcinoma cell lines with different levels of EGFR expression, and investigated the photothermal effects of ICG containing nanocapsules on EGFR-rich tumor cells. Significant thermal toxicity was observed for encapsulated ICG as compared to free ICG at 808 nm laser irradiation with radiant exposure of 6 W/cm2. These results illustrate the ability to design a colloidal material with cell targeting and heat generating capabilities using non-covalent chemistry. PMID:20092330

  17. Syntheses and characterization of lisinopril-coated gold nanoparticles as highly stable targeted CT contrast agents in cardiovascular diseases.

    PubMed

    Ghann, William E; Aras, Omer; Fleiter, Thorsten; Daniel, Marie-Christine

    2012-07-17

    Lisinopril was used as the targeting moiety to prepare gold nanoparticle-based functional CT contrast agents. Pure lisinopril, thioctic acid-lisinopril conjugate, and reduced thioctic acid-lisinopril conjugate were used to obtain GNP-Lis, GNP-TA-Lis, and GNP-RTA-Lis, respectively, via ligand exchange reaction on citrate-coated gold nanoparticles (GNPs). These lisinopril-decorated GNPs were fully characterized, and their chemical stabilities in biological relevant media and in high salt concentration were compared. Their relative stabilities toward lyophilization and against cyanide-induced decomposition were also investigated. Because of their higher stability, GNP-TA-Lis were used to assess the targeting of angiotensin converting enzyme (ACE) using X-ray computed tomography (CT). The images obtained displayed high contrast in the region of the lungs and heart, clearly indicating the targeting of ACE, whose overexpression is associated with development of cardiac and pulmonary fibrosis. Thus, the new nanoprobes prepared here will serve as very useful tools for the monitoring of cardiovascular pathophysiologies using CT imaging.

  18. Folate receptor mediated in vivo targeted delivery of human serum albumin coated manganese ferrite magnetic nanoparticles to cancer cells

    NASA Astrophysics Data System (ADS)

    Zaidan, A.; Ilhami, F.; Fahmi, M. Z.; Purwanto, B.; Kharisma, R. Z.

    2017-05-01

    Manganese ferrite nanoparticles (MnFe2O4) have received increasing attention due to their remarkable magnetic properties and have been used for various biomedical applications. They have potential applications in magnetic resonance imaging and hyperthermia for cancer. Both novel applications require a delivery system that will allow nanoparticle to move easily and localization of nanoparticle to the target tissue. In our work, we developed human serum albumin coated manganese ferrite magnetic nanoparticles (HSA-MF NPs). The nanoparticles were prepared using solvothermal method and modified with folic acid for targeted delivery. Structure and morphology of manganese ferrite nanoparticle were characterized by X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM). The size of folic acid conjugated HSA-MF NPs (HSA-MF-FA NPs) were studied by dynamic light scattering (DLS). In the in vivo study, we used benzopyrene-induced cancer in mice. We successfully delivered HSA-MF-FA NPs through intravenous tail injection after induction of the tumour. We found that 54% of initial HSA-MF-FA NPs which previously injected localize in the target tissue. While obtained p-value from independent T-test is 0.013 which shows that there is a difference between the control group (HSA-MF NPs) and the treated group (HSA-MF-FA NPs)

  19. Q-ratios and the target return on equity for utilities

    SciTech Connect

    Harlow, F.

    1984-04-12

    An index of profitability derived from the economic theories of efficient markets and resource allocation is useful in the analysis of utility rate of return adequacy, emphasizing the value of utility investments relative to those in other industries. Comparison of this index (the Q-ratio) for a given utility with a nonregulated benchmark ratio is presented here as a method of clarifying investor perceptions of regulatory limits on rate of return to utility capital. In this, the second of two articles, the author provides an example of the application of Q-ratio theory and comments on what adjustments in market price per share and level of return on equity may be necessary to achieve parity with investment in an unregulated environment. 3 footnotes and references.

  20. Target Super-Resolution Compensation for Coherent Airborne Radar Utilizing Spread Spectrum Waveforms.

    DTIC Science & Technology

    1983-12-01

    47 Sampled Signal Theory..............................54 IV. Computer Simulation Development........................58 Approach...Solving Approach In order to determine the feasibility of the narrowband target filter, a computer simulation will be implemented. Signal parameters are...function has a Gaussian frequency spectrum. Various computer runs will be made, testing the waveforms developed in Chapter II and the coherent target

  1. The utility of yeast as a tool for cell-based, target-directed high-throughput screening.

    PubMed

    Norcliffe, J L; Alvarez-Ruiz, E; Martin-Plaza, J J; Steel, P G; Denny, P W

    2014-01-01

    Many Neglected Tropical Diseases (NTDs) have recently been subject of increased focus, particularly with relation to high-throughput screening (HTS) initiatives. These vital endeavours largely rely of two approaches, in vitro target-directed screening using biochemical assays or cell-based screening which takes no account of the target or targets being hit. Despite their successes both of these approaches have limitations; for example, the production of soluble protein and a lack of cellular context or the problems and expense of parasite cell culture. In addition, both can be challenging to miniaturize for ultra (u)HTS and expensive to utilize. Yeast-based systems offer a cost-effective approach to study and screen protein targets in a direct-directed manner within a eukaryotic cellular context. In this review, we examine the utility and limitations of yeast cell-based, target-directed screening. In particular we focus on the currently under-explored possibility of using such formats in uHTS screening campaigns for NTDs.

  2. Enhanced binding and killing of target tumor cells by drug-loaded liposomes modified with tumor-specific phage fusion coat protein

    PubMed Central

    Wang, Tao; D’Souza, Gerard GM; Bedi, Deepa; Fagbohun, Olusegun A; Potturi, L Prasanna; Papahadjopoulos-Sternberg, Brigitte; Petrenko, Valery A; Torchilin, Vladimir P

    2010-01-01

    Aim To explore cancer cell-specific phage fusion pVIII coat protein, identified using phage display, for targeted delivery of drug-loaded liposomes to MCF-7 breast cancer cells. Material & methods An 8-mer landscape library f8/8 and a biopanning protocol against MCF-7 cells were used to select a landscape phage protein bearing MCF-7-specific peptide. Size and morphology of doxorubicin-loaded liposomes modified with the tumor-specific phage fusion coat protein (phage–Doxil) were determined by dynamic light scattering and freeze-fraction electron microscopy. Topology of the phage protein in liposomes was examined by western blot. Association of phage–Doxil with MCF-7 cells was evaluated by fluorescence microscopy and fluorescence spectrometry. Selective targeting to MCF-7 was shown by FACS using a coculture model with target and nontarget cells. Phage–Doxil-induced tumor cell killing and apoptosis were confirmed by CellTiter-Blue® Assay and caspase-3/CPP32 fluorometric assay. Results A chimeric phage fusion coat protein specific towards MCF-7 cells, identified from a phage landscape library, was directly incorporated into the liposomal bilayer of doxorubicin-loaded PEGylated liposomes (Doxil®) without additional conjugation with lipophilic moieties. Western blotting confirmed the presence of both targeting peptide and pVIII coat protein in the phage–Doxil, which maintained the liposomal morphology and retained a substantial part of the incorporated drug after phage protein incorporation. The binding activity of the phage fusion pVIII coat protein was retained after incorporation into liposomes, and phage–Doxil strongly and specifically targeted MCF-7 cells, demonstrating significantly increased cytotoxicity towards target cells in vitro. Conclusion We present a novel and straightforward method for making tumor-targeted nanomedicines by anchoring specific phage proteins (substitute antibodies) on their surface. PMID:20528452

  3. Passive tumor targeting and imaging by using mercaptosuccinic acid-coated near-infrared quantum dots

    PubMed Central

    Lin, Guimiao; Wang, Xiaomei; Yin, Feng; Yong, Ken-Tye

    2015-01-01

    In this paper, we demonstrate the preparation of monodispersed quantum dots (QDs) as near-infrared (NIR) optical probes for in vivo pancreatic cancer targeting and imaging. The design of these luminescent probes involves functionalizing NIR QDs with ligand mercaptosuccinic acid (MSA), which targets the tumor site by enhanced permeability and retention effect. The colloidal and optical stability of the QDs can be maintained for >1 week. In vivo optical imaging studies in nude mice bearing pancreatic tumor show that the probes accumulate at tumor sites for >2.5 hours following intravenous injection of the functionalized NIR QDs. Tumor-labeling studies showed no evidence of harmful effects on the treated animals, even at a dose as high a ~50 mg/kg. These results demonstrate that the engineered MSA-functionalized QDs can serve as a diagnostic platform for early detection of cancer, as well as in image-guided precise surgical resection of tumors. PMID:25609948

  4. Plant-Scale Concentration Column Designs for SHINE Target Solution Utilizing AG 1 Anion Exchange Resin

    SciTech Connect

    Stepinski, Dominique C.; Vandegrift, G. F.

    2015-09-30

    Argonne is assisting SHINE Medical Technologies (SHINE) in their efforts to develop SHINE, an accelerator-driven process that will utilize a uranyl-sulfate solution for the production of fission product Mo-99. An integral part of the process is the development of a column for the separation and recovery of Mo-99, followed by a concentration column to reduce the product volume from 15-25 L to <1 L. Argonne has collected data from batch studies and breakthrough column experiments to utilize the VERSE (Versatile Reaction Separation) simulation program (Purdue University) to design plant-scale product recovery and concentration processes.

  5. Polyamine/salt-assembled microspheres coated with hyaluronic acid for targeting and pH sensing.

    PubMed

    Zhang, Pan; Yang, Hui; Wang, Guojun; Tong, Weijun; Gao, Changyou

    2016-06-01

    The poly(allylamine hydrochloride)/trisodium citrate aggregates were fabricated and further covalently crosslinked via the coupling reaction of carboxylic sites on trisodium citrate with the amine groups on polyamine, onto which poly-L-lysine and hyaluronic acid were sequentially assembled, forming stable microspheres. The pH sensitive dye and pH insensitive dye were further labeled to enable the microspheres with pH sensing property. Moreover, these microspheres could be specifically targeted to HeLa tumor cells, since hyaluronic acid can specifically recognize and bind to CD44, a receptor overexpressed on many tumor cells. Quantitative pH measurement by confocal laser scanning microscopy demonstrated that the microspheres were internalized into HeLa cells, and accumulated in acidic compartments. By contrast, only a few microspheres were adhered on the NIH 3T3 cells surface. The microspheres with combined pH sensing property and targeting ability can enhance the insight understanding of the targeted drug vehicles trafficking after cellular internalization.

  6. Targeting etoposide to acute myelogenous leukaemia cells using nanostructured lipid carriers coated with transferrin

    NASA Astrophysics Data System (ADS)

    Khajavinia, Amir; Varshosaz, Jaleh; Jafarian Dehkordi, Abbas

    2012-10-01

    The aim of the present study was to evaluate the diverse properties of transferrin (Tf)-conjugated nanostructured lipid carriers (NLCs) prepared using three different fatty amines, including stearylamine (SA), dodecylamine (DA) and spermine (SP), and two different methods for Tf coupling. Etoposide-loaded NLCs were prepared by an emulsion-solvent evaporation method followed by probe sonication. Chemical coupling of NLCs with Tf was mediated by an amide linkage between the surface-exposed amino group of the fatty amine and the carboxyl group of the protein. The physical coating was performed in a Ringer-Hepes buffer medium. NLCs were characterized by their particle size, zeta potential, polydispersity index, drug entrapment percentage, drug release profiles and Tf-coupling efficiency. The cytotoxicity of NLCs on K562 acute myelogenous leukaemia cells was studied by MTT assay, and their cellular uptake was studied by a flow cytometry method. SA-containing NLCs showed the lowest particle size, the highest zeta potential and the largest coupling efficiency values. The drug entrapment percentage and the zeta potential decreased after Tf coupling, but the average particle size increased. SP-containing formulations released their drug contents comparatively slower than SA- or DA-containing NLCs. Unconjugated NLCs released moderately more drug than Tf-NLCs. Flow cytometry studies revealed enhanced cellular uptake of Tf-NLCs compared to unconjugated ones. Blocking Tf receptors resulted in a significantly higher cell survival rate for Tf-NLCs. The highest cytotoxic activity was observed in the chemically coupled SA-containing nanoparticles, with an IC50 value of 15-fold lower than free etoposide.

  7. Inhibition of neo-intimal hyperplasia in porcine coronary arteries utilizing a novel paclitaxel-coated scoring balloon catheter.

    PubMed

    Cremers, Bodo; Schmitmeier, Stephanie; Clever, Yvonne P; Gershony, Gary; Speck, Ulrich; Scheller, Bruno

    2014-12-01

    Scoring balloons are particularly useful in the acute treatment of fibro-calcific, bifurcation and in-stent restenosis lesions but have not been shown to affect the restenosis rate. Conventional balloons coated with paclitaxel have recently been shown to reduce restenosis rates in certain lesion subsets, but are associated with suboptimal acute results. A novel paclitaxel-coated scoring balloon was developed to overcome these limitations. AngioSculpt(®) scoring balloons (SB) were coated with paclitaxel admixed with a specific excipient. Four in vitro and in vivo studies were performed: (a) loss of the drug during passage to the lesion, (b) transfer of the drug to the vessel wall; (c) inhibition of neo-intimal proliferation in porcine coronary arteries as compared to uncoated SB and the Paccocath™, and (d) evaluation of the dose-response to 1.5-12 μg of paclitaxel/mm(2) . Drug loss during delivery to the lesion was 17% ± 8%, and transfer to the vessel wall was 9% ± 4% of dose on unused balloons. The paclitaxel-coated SB resulted in a lower late lumen loss of 0.27 ± 0.24 mm compared to 1.4 ± 0.7 mm with the uncoated SB (P = 0.001). Histomorphometry revealed larger luminal areas of 6.8 ± 1.6 mm(2) (paclitaxel-coated SB) and 5.8 ± 1.7 mm(2) (Paccocath) as compared to the uncoated SB (2.3 ± 1.5 mm(2) ; P = 0.001). No coating related adverse effects were observed on follow-up angiography or histologic examination at the treatment site or downstream myocardium. A novel paclitaxel-coated SB leads to a significant inhibition of neointimal proliferation in the porcine coronary model. © 2013 Wiley Periodicals, Inc.

  8. Improvement of corrosion protection property of Mg-alloy by DLC and Si-DLC coatings with PBII technique and multi-target DC-RF magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Masami, Ikeyama; Setsuo, Nakao; Tsutomu, Sonoda; Junho, Choi

    2009-05-01

    Magnesium alloys have been considered as one of the most promising light weight materials with potential applications for automobile and aircraft components. Their poor corrosion resistance, however, has to date prevented wider usage. Diamond-like carbon (DLC) and silicon-incorporated DLC (Si-DLC) coatings are known to provide a high degree of corrosion protection, and hold accordingly promise for enhancing the corrosion resistance of the magnesium alloys. In this work we have studied the effect of coating conditions of DLC coatings as well as Si incorporation into coating on corrosion resistance, deposited onto AZ91 magnesium alloy substrates by plasma based ion implantation (PBII). The influences of a Ti interlayer beneath the DLC, Si-DLC and Ti incorporated DLC (Ti-DLC) coatings fabricated by multi-target direct-current radio-frequency (DC-RF) magnetron sputtering were also examined on both the adhesion strength and corrosion resistance of the materials. We have also examined the effect of the Si content in the Si-DLC coatings made by magnetron sputtering on the alloys' corrosion resistance. The results of potentiodynamic polarization measurements demonstrate that Si-DLC coating deposited by PBII exhibits the highest corrosion resistance in an aqueous 0.05 M NaCl solution. Although Ti layer is helpful in increasing adhesion between DLC coating and AZ91 substrate, it also influences adversely corrosion protection. The ozone treatment of the magnesium alloy's surface before the formation of coatings has been found to improve both adhesion strength and corrosion resistance.

  9. Polymer-based metal nano-coated disposable target for matrix-assisted and matrix-free laser desorption/ionization mass spectrometry.

    PubMed

    Bugovsky, Stefan; Winkler, Wolfgang; Balika, Werner; Koranda, Manfred; Allmaier, Günter

    2016-07-15

    The ideal MALDI/LDI mass spectrometry sample target for an axial TOF instrument possesses a variety of properties. Primarily, it should be chemically inert to the sample, i.e. analyte, matrix and solvents, highly planar across the whole target, without any previous chemical contact and provide a uniform surface to facilitate reproducible measurements without artifacts from previous sample or matrix compounds. This can be hard to achieve with a metal target, which has to be extensively cleaned every time after use. Any cleaning step may leave residues behind, may change the surface properties due to the type of cleaning method used or even cause microscopic scratches over time hence altering matrix crystallization behavior. Alternatively, use of disposable targets avoids these problems. As each possesses the same surface they therefore have the potential to replace the conventional full metal targets so commonly employed. Furthermore, low cost single-use targets with high planarity promise an easier compliance with GLP guidelines as they alleviate the problem of low reproducibility due to inconsistent sample/matrix crystallization and changes to the target surface properties. In our tests, polymeric metal nano-coated targets were compared to a stainless steel reference. The polymeric metal nano-coated targets exhibited all the performance characteristics for a MALDI MS sample support, and even surpassed the - in our lab commonly used - reference in some aspects like limit of detection. The target exhibits all necessary features such as electrical conductivity, vacuum, laser and solvent compatibility.

  10. Gold-Coated Fe3O4 Nanoroses with Five Unique Functions for Cancer Cell Targeting, Imaging and Therapy.

    PubMed

    Li, Chunmei; Chen, Tao; Ocsoy, Ismail; Zhu, Guizhi; Yasun, Emir; You, Mingxu; Wu, Cuichen; Zheng, Jing; Song, Erqun; Huang, Cheng Zhi; Tan, Weihong

    2014-03-26

    The development of nanomaterials that combine diagnostic and therapeutic functions within a single nanoplatform is extremely important for molecular medicine. Molecular imaging with simultaneous diagnosis and therapy will provide the multimodality needed for accurate diagnosis and targeted therapy. Here, we demonstrate gold-coated iron oxide (Fe3O4@Au) nanoroses with five distinct functions, which integrate aptamer-based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal therapy and chemotherapy into one single probe. The inner Fe3O4 core functions as an MRI agent, while the photothermal effect is achieved through near-infrared absorption by the gold shell, causing a rapid rise in temperature and also resulting in a facilitated release of the anticancer drug doxorubicin carried by the nanoroses. Where the doxorubicin is released is monitored by its fluorescent. Aptamers immobilized on the surfaces of the nanoroses enable efficient and selective drug delivery, imaging and photothermal effect with high specificity. The five-function-embedded nanoroses show great advantages in multimodality.

  11. Reducing Non-Specific Binding and Uptake of Nanoparticles and Improving Cell Targeting with an Antifouling PEO-b-PγMPS Copolymer Coating

    PubMed Central

    Chen, Hongwei; Yeh, Julie; Wang, Liya; Wu, Xinying; Cao, Zehong; Wang, Y. Andrew; Zhang, Minming; Yang, Lily; Mao, Hui

    2010-01-01

    One of the major limitations impeding the sensitivity and specificity of biomarker targeted nanoparticles is non-specific binding by biomolecules and uptake by the reticuloendothelial system (RES). We report the development of an antibiofouling polysiloxane containing amphiphilic diblock copolymer, poly(ethylene oxide)-block-poly(γ-methacryloxypropyltrimethoxysilane) (PEO-b-PγMPS), for coating and functionalizing high quality hydrophobic nanocrystals such as iron oxide nanoparticles and quantum dots. These PEO-b-PγMPS coated nanocrystals were colloidally stable in biological medium and showed low non-specific binding by macromolecules after incubation with 100% fetal bovine serum. Both in vitro experiments with macrophages and in vivo biodistribution studies in mice revealed that PEO-b-PγMPS copolymer coated nanocrystals have an antibiofouling effect that reduces non-specific cell and RES uptake. Surface functionalization with amine groups was accomplished through co-crosslinking the polysiloxane coating layer and (3-Aminopropyl) trimethoxysilane in aqueous solution. Tumor integrin αvβ3 targeting peptide cyclo-RGD ligands were conjugated on the nanoparticles through a heterobifunctional linker. The resulting integrin αvβ3 targeting nanoparticle conjugates showed improved cancer cell targeting with a stronger affinity to U87MG glioma cells, which have a high expression of αvβ3 integrins, but minimal binding to MCF-7 (low expression of αvβ3 integrins). PMID:20398933

  12. Small Target Detection Utilizing Robust Methods of the Human Visual System for IRST

    NASA Astrophysics Data System (ADS)

    Kim, Sungho; Yang, Yukyung; Lee, Joohyoung; Park, Yongchan

    2009-09-01

    Robust detection of small targets is very important in IRST (Infrared Search and Track). This paper presents a novel mathematical method for the incoming target detection problem in cluttered background motivated from the robust properties of human visual system (HVS). The HVS shows the best efficiency and robustness for an object detection task. The robust properties of the HVS are contrast mechanism, multi-resolution representation, size adaptation, and pop-out phenomena. Based on these facts, a plausible computational model integrating these facts is proposed using Laplacian scale-space theory and Tune-Max based optimization method. Simultaneous target signal enhancement and background clutter suppression is achieved by tuning and maximizing the signal-to-clutter ratio (TMSCR) in Laplacian scale-space. At the first stage, the Tune-Max of the signal to background contrast produces candidate targets with adapted scale. At the second stage, the Tune-Max of the signal-to-clutter ratio (SCR) produces maximal SCR which is used to pop-out detections. Experimental evaluation results for the incoming target sequence validate the upgraded detection capability of the proposed method compared with the Top-hat method at the same false alarm rate. Experimental results for the six kinds of cluttered background images show that the proposed TMSCR produces less false alarms (4.3 times reduction) compared to the Top-hat at the same detection rate.

  13. 3D modeling of large targets and clutter utilizing Ka band monopulse SAR

    NASA Astrophysics Data System (ADS)

    Ray, Jerry A.; Barr, Doug; Shurtz, Ric; Channell, Rob

    2006-05-01

    The U.S. Army Research, Development and Engineering Command at Redstone Arsenal, Alabama have developed a dual mode, Ka Band Radar and IIR system for the purpose of data collection and tracker algorithm development. The system is comprised of modified MMW and IIR sensors and is mounted in a stabilized ball on a UH-1 helicopter operated by Redstone Technical Test Center. Several missile programs under development require MMW signatures of multiple target and clutter scenes. Traditionally these target signatures have been successfully collected using static radars and targets mounted on a turntable to produce models from ISAR images; clutter scenes have been homogeneously characterized using information on various classes of clutter. However, current and future radar systems require models of many targets too large for turntables, as well as high resolution 3D scattering characteristics of urban and other non-homogenous clutter scenes. In partnership with industry independent research and development (IRAD) activities the U.S. Army RDEC has developed a technique for generating 3D target and clutter models using SAR imaging in the MMW spectrum. The purpose of this presentation is to provide an overview of funded projects and resulting data products with an emphasis on MMW data reduction and analysis, especially the unique 3D modeling capabilities of the monopulse radar flying SAR profiles. Also, a discussion of lessons learned and planned improvements will be presented.

  14. Super-characteristic x-ray generator utilizing a pipe and rod target

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Izumisawa, Mitsuru; Takahashi, Kiyomi; Sato, Shigehiro; Ichimaru, Toshio; Takayama, Kazuyoshi

    2006-08-01

    This generator consists of the following components: a constant high-voltage power supply, a filament power supply, a turbomolecular pump, and an x-ray tube. The x-ray tube is a demountable diode which is connected to the turbomolecular pump and consists of the following major devices: a tungsten hairpin cathode (filament), a focusing (Wehnelt) electrode, a polyethylene terephthalate x-ray window 0.25 mm in thickness, a stainless-steel tube body, a pipe target, and a rod target. The pipe and rod targets are useful for forming linear and cone beams, respectively. In the x-ray tube, the positive high voltage is applied to the anode (target) electrode, and the cathode is connected to the tube body (ground potential). In this experiment, the tube voltage applied was from12 to 20 kV, and the tube current was regulated to within 0.10 mA by the filament temperature. The exposure time is controlled in order to obtain optimum x-ray intensity. The electron beams from the cathode are converged to the target by the focusing electrode, and clean K-series characteristic x-rays are produced through the focusing electrode without using a filter. The x-ray intensities of the pipe and rod targets were 1.29 and 4.28 μGy/s at 1.0 m from the x-ray source with a tube voltage of 15 kV and a tube current of 0.10 mA, and quasi-monochromatic radiography was performed using a computed radiography system.

  15. Low Mutation Burden in Ovarian Cancer May Limit the Utility of Neoantigen-Targeted Vaccines

    PubMed Central

    Brown, Scott D.; Wick, Darin A.; Nielsen, Julie S.; Kroeger, David R.; Twumasi-Boateng, Kwame; Holt, Robert A.; Nelson, Brad H.

    2016-01-01

    Due to advances in sequencing technology, somatically mutated cancer antigens, or neoantigens, are now readily identifiable and have become compelling targets for immunotherapy. In particular, neoantigen-targeted vaccines have shown promise in several pre-clinical and clinical studies. However, to date, neoantigen-targeted vaccine studies have involved tumors with exceptionally high mutation burdens. It remains unclear whether neoantigen-targeted vaccines will be broadly applicable to cancers with intermediate to low mutation burdens, such as ovarian cancer. To address this, we assessed whether a derivative of the murine ovarian tumor model ID8 could be targeted with neoantigen vaccines. We performed whole exome and transcriptome sequencing on ID8-G7 cells. We identified 92 somatic mutations, 39 of which were transcribed, missense mutations. For the 17 top predicted MHC class I binding mutations, we immunized mice subcutaneously with synthetic long peptide vaccines encoding the relevant mutation. Seven of 17 vaccines induced robust mutation-specific CD4 and/or CD8 T cell responses. However, none of the vaccines prolonged survival of tumor-bearing mice in either the prophylactic or therapeutic setting. Moreover, none of the neoantigen-specific T cell lines recognized ID8-G7 tumor cells in vitro, indicating that the corresponding mutations did not give rise to bonafide MHC-presented epitopes. Additionally, bioinformatic analysis of The Cancer Genome Atlas data revealed that only 12% (26/220) of HGSC cases had a ≥90% likelihood of harboring at least one authentic, naturally processed and presented neoantigen versus 51% (80/158) of lung cancers. Our findings highlight the limitations of applying neoantigen-targeted vaccines to tumor types with intermediate/low mutation burdens. PMID:27192170

  16. Radiative transfer modeling of dust-coated Pancam calibration target materials: Laboratory visible/near-infrared spectrogoniometry

    USGS Publications Warehouse

    Johnson, J. R.; Sohl-Dickstein, J.; Grundy, W.M.; Arvidson, R. E.; Bell, J.F.; Christensen, P.R.; Graff, T.; Guinness, E.A.; Kinch, K.; Morris, Robert; Shepard, M.K.

    2006-01-01

    Laboratory visible/near-infrared multispectral observations of Mars Exploration Rover Pancam calibration target materials coated with different thicknesses of Mars spectral analog dust were acquired under variable illumination geometries using the Bloomsburg University Goniometer. The data were fit with a two-layer radiative transfer model that combines a Hapke formulation for the dust with measured values of the substrate interpolated using a He-Torrance approach. We first determined the single-scattering albedo, phase function, opposition effect width, and amplitude for the dust using the entire data set (six coating thicknesses, three substrates, four wavelengths, and phase angles 3??-117??). The dust exhibited single-scattering albedo values similar to other Mars analog soils and to Mars Pathfinder dust and a dominantly forward scattering behavior whose scattering lobe became narrower at longer wavelengths. Opacity values for each dust thickness corresponded well to those predicted from the particles sizes of the Mars analog dust. We then restricted the number of substrates, dust thicknesses, and incidence angles input to the model. The results suggest that the dust properties are best characterized when using substrates whose reflectances are brighter and darker than those of the deposited dust and data that span a wide range of dust thicknesses. The model also determined the dust photometric properties relatively well despite limitations placed on the range of incidence angles. The model presented here will help determine the photometric properties of dust deposited on the MER rovers and to track the multiple episodes of dust deposition and erosion that have occurred at both landing sites. Copyright 2006 by the American Geophysical Union.

  17. Development and characterization of magnetic iron oxide nanoparticles with a cisplatin-bearing polymer coating for targeted drug delivery.

    PubMed

    Unterweger, Harald; Tietze, Rainer; Janko, Christina; Zaloga, Jan; Lyer, Stefan; Dürr, Stephan; Taccardi, Nicola; Goudouri, Ourania-Menti; Hoppe, Alexander; Eberbeck, Dietmar; Schubert, Dirk W; Boccaccini, Aldo R; Alexiou, Christoph

    2014-01-01

    conclusion, combination of dextran-coated SPIONs with hyaluronic acid and cisplatin represents a promising approach for magnetic drug targeting in the treatment of cancer.

  18. Development and characterization of magnetic iron oxide nanoparticles with a cisplatin-bearing polymer coating for targeted drug delivery

    PubMed Central

    Unterweger, Harald; Tietze, Rainer; Janko, Christina; Zaloga, Jan; Lyer, Stefan; Dürr, Stephan; Taccardi, Nicola; Goudouri, Ourania-Menti; Hoppe, Alexander; Eberbeck, Dietmar; Schubert, Dirk W; Boccaccini, Aldo R; Alexiou, Christoph

    2014-01-01

    . In conclusion, combination of dextran-coated SPIONs with hyaluronic acid and cisplatin represents a promising approach for magnetic drug targeting in the treatment of cancer. PMID:25120363

  19. Genetically Targeted Radiotherapy Utilizing the Human Sodium Iodide Symporter in Human Breast Carcinoma Cells

    DTIC Science & Technology

    2005-04-01

    to concentrate isotopes has been utilized clinically for years in thyroid imaging, treatment of hyperthyroidism , and for treating well-differentiated...expression after retinoic acid treatments . This treatment may turn on lactoperoxidase expression as well increasing the retention of radioactivity in the...tumor. LPO treatment did increase retention of 1-125 in Ad-NIS treated cells compared to Ad-NIS treatment alone. The acquisition of a pin-hole

  20. How Does Target Know so Much about Its Customers? Utilizing Customer Analytics to Make Marketing Decisions

    ERIC Educational Resources Information Center

    Corrigan, Hope B.; Craciun, Georgiana; Powell, Allison M.

    2014-01-01

    Every time shoppers make a purchase at a store or browse a Web site, customer behavior is tracked, analyzed, and perhaps shared with other businesses. Target Corporation is a leader in analyzing vast amounts of data to identify buying patterns, improve customer satisfaction, predict future trends, select promotional strategies, and increase…

  1. How Does Target Know so Much about Its Customers? Utilizing Customer Analytics to Make Marketing Decisions

    ERIC Educational Resources Information Center

    Corrigan, Hope B.; Craciun, Georgiana; Powell, Allison M.

    2014-01-01

    Every time shoppers make a purchase at a store or browse a Web site, customer behavior is tracked, analyzed, and perhaps shared with other businesses. Target Corporation is a leader in analyzing vast amounts of data to identify buying patterns, improve customer satisfaction, predict future trends, select promotional strategies, and increase…

  2. Analytic expressions for atomic layer deposition: Coverage, throughput, and materials utilization in cross-flow, particle coating, and spatial atomic layer deposition

    SciTech Connect

    Yanguas-Gil, Angel; Elam, Jeffrey W.

    2014-05-15

    In this work, the authors present analytic models for atomic layer deposition (ALD) in three common experimental configurations: cross-flow, particle coating, and spatial ALD. These models, based on the plug-flow and well-mixed approximations, allow us to determine the minimum dose times and materials utilization for all three configurations. A comparison between the three models shows that throughput and precursor utilization can each be expressed by universal equations, in which the particularity of the experimental system is contained in a single parameter related to the residence time of the precursor in the reactor. For the case of cross-flow reactors, the authors show how simple analytic expressions for the reactor saturation profiles agree well with experimental results. Consequently, the analytic model can be used to extract information about the ALD surface chemistry (e.g., the reaction probability) by comparing the analytic and experimental saturation profiles, providing a useful tool for characterizing new and existing ALD processes.

  3. Targeting and therapy of human glioma xenografts in vivo utilizing radiolabeled antibodies

    SciTech Connect

    Williams, J.A.; Wessels, B.W.; Edwards, J.A.; Kopher, K.A.; Wanek, P.M.; Wharam, M.D.; Order, S.E.; Klein, J.L. )

    1990-02-01

    Radiolabeled antibodies provide a potential basis for selective radiotherapy of human gliomas. We have measured tumor targeting by radiolabeled monoclonal antibodies directed against neuroectodermal and tumor-associated antigens in nude mice bearing human glioma xenografts. Monoclonal P96.5, a mouse IgG2a immunoglobulin, defines an epitope of a human melanoma cell surface protein and specifically binds the U-251 human glioma as measured by immunoperoxidase histochemistry. IIIIn-radiolabeled P96.5 specifically targets the U-251 human glioma xenograft and yields 87.0 microCi of tumor activity/g/100 microCi injected activity compared to 4.5 microCi following administration of 100 microCi radiolabeled irrelevant monoclonal antibody. Calculations of targeting ratios demonstrate the deposited dose to be 11.6 times greater with radiolabeled P96.5 administration compared to irrelevant monoclonal antibody. The dose found in normal organs is less than 20% of that in the tumor, further supporting specific targeting of the human glioma xenograft by this antibody. Monoclonal antibody ZME018, which defines a second melanoma-associated antigen, demonstrates positive immunoperoxidase staining of the tumor, but comparatively decreased targeting. To test the therapeutic potential of 90Y-radiolabeled P96.5 and ZME018, tumors and normal sites were implanted with miniature thermoluminescent dosimeters. Average absorbed doses of 3770 +/- 445 (SEM) and 645 +/- 48 cGy in tumor, 353 +/- 41 and 222 +/- 13 cGy in a contralateral control i.m. site, 980 +/- 127 and 651 +/- 63 cGy in liver, and 275 +/- 14 and 256 +/- 18 cGy in total body were observed 7 days following administration of 100 microCi 90Y-radiolabeled P96.5 and ZME018, respectively. Calculations of absorbed dose by the medical internal radiation dose method confirmed thermoluminescent dosimeter absorbed dose measurements.

  4. Arthrodesis Rate and Patient Reported Outcomes After Anterior Lumbar Interbody Fusion Utilizing a Plasma-Sprayed Titanium Coated PEEK Interbody Implant: A Retrospective, Observational Analysis

    PubMed Central

    Bergen, Sophea R.; Staples, Miranda; Liang, Kevin; Raiszadeh, Ramin

    2017-01-01

    Background Anterior lumbar interbody fusion (ALIF) is utilized in symptomatic spinal disc destabilization due to degenerative lumbar disc disease, isthmic and degenerative spondylolisthesis, internal disc disruption, or pseudarthrosis after non-operative treatments fail. The addition of a plasma-sprayed titanium coating (PTC) to polyether ether ketone spacers (PEEK) may reduce the rate of implant subsidence or non-union secondary to poor osseous-integration of non-coated PEEK or metal interbody systems. Methods A retrospective, non-randomized, single-center chart review, evaluated the post-surgical follow-up data of patients receiving a PTC PEEK implant during single or multi-level ALIF procedures to determine the clinical efficacy and rate of arthrodesis after utilization of a coated spacer. Standard roentgenographs or computed tomography were used to identify successful arthrodesis following the ALIF procedure and longitudinal clinical improvements were determined by scores on the Visual Analog Scale (VAS) for low back and leg pain. Results Forty-four subjects (48% male, mean=53 years) were included in this chart review. Follow-up radiology demonstrated radiographic union with bridging bone formation across the interbody space for 42/44 (96%) individuals with solid arthrodesis occurring at an average of 7.3 ± 2.3 months. Subjects demonstrated significant improvement in VAS low back pain (4.5 ± 2.4 point improvement, p=0.0001) and VAS leg pain (4.1 ± 3.3 point improvement, p=0.0001). While there was a significant reduction in the improvement of VAS low back pain of Worker's Compensation claimants as compared to other patients (3.9 ± 2.4 vs. 5.3 ± 2.1), there was no difference in VAS low back pain or leg pain when the data was stratified by gender, age, tobacco use, comorbidities, prior surgery, fusion construct length, use of supplemental posterior instrumentation, BMI, or diagnosis. Conclusions This study provides support that the addition of a PTC coating

  5. Utilizing a Segmented Fuel Cell to Study the Effects of Electrode Coating Irregularities on PEM Fuel Cell Initial Performance

    DOE PAGES

    Phillips, Adam; Ulsh, Michael; Porter, Jason; ...

    2017-04-27

    An understanding of the impact of coating irregularities on beginning of life polymer electrolyte fuel cell (PEMFC) performance is essential to develop and establish manufacturing tolerances for its components. Coating irregularities occurring in the fuel cell electrode can either possess acceptable process variations or potentially harmful defects. A segmented fuel cell (SFC) is employed to understand how 100% catalyst reduction irregularities ranging from 0.125 to 1 cm2 in the cathode electrode of a 50 cm2 sized cell impact spatial and total cell performance at dry and wet humidification conditions. Here, by analyzing the data in a differential format the localmore » performance effects of irregularity sizes down to 0.25 cm2 were detected in the current distribution of the cell. Slight total cell performance impacts, due to irregularity sizes of 0.5 and 1 cm2, were observed under dry operation and high current densities.« less

  6. Performance comparison of flat plate collector absorber coatings utilizing NBS Standard 74-635 and the ASHRAE Collector Performance Method

    NASA Astrophysics Data System (ADS)

    Ingley, H. A.; Farber, E. A.; Reinhardt, R.

    Mildly selective (Chemglaze Z306 and Solarsorb C-1077 paints) surfaces, along with flat black paint and untreated copper, were evaluated as flat-plate solar collector coatings according to the National Bureau of Standards and the American Society of Heating, Refrigeration and Air Conditioning Engineers procedures for determining solar absorptivity. The moderately selective surfaces proved less efficient than flat black paint for operating temperatures less than 180 F. Highly selective (black chrome and copper oxide) surfaces, although tested, were not evaluated.

  7. Utilization of wheat straw for the preparation of coated controlled-release fertilizer with the function of water retention.

    PubMed

    Xie, Lihua; Liu, Mingzhu; Ni, Boli; Wang, Yanfang

    2012-07-18

    With the aim of improving fertilizer use efficiency and minimizing the negative impact on the environment, a new coated controlled-release fertilizer with the function of water retention was prepared. A novel low water solubility macromolecular fertilizer, poly(dimethylourea phosphate) (PDUP), was "designed" and formulated from N,N'-dimethylolurea (DMU) and potassium dihydrogen phosphate. Simultaneously, an eco-friendly superabsorbent composite based on wheat straw (WS), acrylic acid (AA), 2-acryloylamino-2-methyl-1-propanesulfonic acid (AMPS), and N-hydroxymethyl acrylamide (NHMAAm) was synthesized and used as the coating to control the release of nutrient. The nitrogen release profile and water retention capacity of the product were also investigated. The degradation of the coating material in soil solution was studied. Meanwhile, the impact of the content of N-hydroxymethyl acrylamide on the degradation extent was examined. The experimental data showed that the product with good water retention and controlled-release capacities, being economical and eco-friendly, could be promising for applications in agriculture and horticulture.

  8. Compact x-ray generator utilizing cerium-target tube for angiography

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ito, Fumihito; Ichimaru, Toshio; Sato, Shigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-11-01

    The cerium-target x-ray tube is useful in order to perform cone beam K-edge angiography because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. The x-ray generator consists of a main controller and a unit with a high-voltage circuit and a fixed anode x-ray tube. The tube is a glass-enclosed diode with a cerium target and a 0.5 mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.3×0.9 mm. Cerium K-series characteristic x rays were left using a 3.0 mm-thick aluminum filter, and the x-ray intensity was 0.59 μC/kg at 1.0 m from the source with a tube voltage of 60 kV, a current of 0.40 mA, and an exposure time of 1.0 s. Angiography was performed with a computed radiography system using iodine-based microspheres 15 μm in diameter. In angiography of non-living animals, we observed fine blood vessels of approximately 100 μm with high contrasts.

  9. Targeted drug delivery system to neural cells utilizes the nicotinic acetylcholine receptor.

    PubMed

    Huey, Rachel; O'Hagan, Barry; McCarron, Paul; Hawthorne, Susan

    2017-06-15

    Drug delivery to the brain is still a major challenge in the field of therapeutics, especially for large and hydrophilic compounds. In order to achieve drug delivery of therapeutic concentration in the central nervous system, the problematic blood brain barrier (BBB) must be overcome. This work presents the formulation of a targeted nanoparticle-based drug delivery system using a specific neural cell targeting ligand, rabies virus derived peptide (RDP). Characterization studies revealed that RDP could be conjugated to drug-loaded PLGA nanoparticles of average diameter 257.10±22.39nm and zeta potential of -5.51±0.73mV. In vitro studies showed that addition of RDP to nanoparticles enhanced drug accumulation in a neural cell line specifically as opposed to non-neural cell lines. It was revealed that this drug delivery system is reliant upon nicotinic acetylcholine receptor (nAChR) function for RDP-facilitated effects, supporting a cellular uptake mechanism of action. The specific neural cell targeting capabilities of RDP via the nAChR offers a non-toxic, non-invasive and promising approach to the delivery of therapeutics to the brain. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  10. The Formulation of Aptamer-Coated Paclitaxel-Polylactide Nanoconjugates and Their Targeting to Cancer Cells

    PubMed Central

    Tong, Rong; Yala, Linda; Fan, Timothy M.; Cheng, Jianjun

    2011-01-01

    Paclitaxel-polylactide (Ptxl-PLA) conjugate nanoparticles, termed as nanoconjugates (NCs), were prepared through Ptxl/(BDI)ZnN(TMS)2 (BDI = 2-((2,6-diisopropylphenyl)-amido)-4-((2,6-diisopropylphenyl)-imino)-2-pentene)-mediated controlled polymerization of lactide (LA) followed by nanoprecipitation. Nanoprecipitation of Ptxl-PLA resulted in sub-100 nm NCs with monomodal particle distributions and low polydispersities. The sizes of Ptxl-PLA NCs could be precisely controlled by using appropriate water-miscible solvents and by controlling the concentration of Ptxl-PLA during nanoprecipitation. Co-precipitation of a mixture of PLA-PEG-PLA (PLA = 14 kDa; PEG = 5kDa) and Ptxl-PLA in PBS resulted in NCs that could stay non-aggregated in PBS for an extended period of time. To develop solid formulations of NCs, we evaluated a series of lyoprotectants, aiming to identify candidates that could effectively reduce or eliminate NC aggregation during lyophilization. Albumin was found to be an excellent lyoprotectant for the preparation of NCs in solid form, allowing lyophilized NCs to be readily dispersed in PBS without noticeable aggregates. Aptamer-NCs bioconjugates were prepared and found to be able to effectively target prostate-specific membrane antigen in a cell-specific manner. PMID:20122727

  11. Zwitterionic amphiphile coated magnetofluorescent nanoparticles - synthesis, characterization and tumor cell targeting.

    PubMed

    Demillo, Violeta G; Zhu, Xiaoshan

    2015-11-14

    Magnetofluorescent nanoparticles (MFNPs) have recently attracted significant research interests due to their potential applications in biological manipulation and imaging. In this work, through a simple and fast self-assembling process, we first report the preparation of zwitterionic MFNPs (ZW-MFNPs) in the form of micelles using our newly synthesized zwitterionic amphiphiles, CuInS2/ZnS quantum dots, and MnFe2O4 magnetic nanoparticles. ZW-MFNPs integrate both MnFe2O4 magnetic nanoparticles and CuInS2/ZnS quantum dots in their hydrophobic cores and zwitterionic groups such as carboxybetaine and sulfobetaine on their hydrophilic shells. ZW-MFNPs possess dual imaging properties, high (Mn + Fe) recovery, excellent stability in aqueous solutions with a wide pH/ionic-strength range and physiological media, minimal cytotoxicity, and specific targeting to brain tumor cells after bioconjugation with chlorotoxin. The unique characteristics of ZW-MFNPs may open an avenue for these particles to be employed in broad biomedical applications.

  12. Hyaluronic acid-coated chitosan nanoparticles induce ROS-mediated tumor cell apoptosis and enhance antitumor efficiency by targeted drug delivery via CD44.

    PubMed

    Wang, Tao; Hou, Jiahui; Su, Chang; Zhao, Liang; Shi, Yijie

    2017-01-10

    A targeted drug nanoparticle (NP) delivery system has shown potential as a possible cancer treatment. Given its merits, such as its selective distribution at tumor sites and its controllable drug release, drug-loaded NPs can be effectively delivered to selected organs and targeted cells, thus enhancing its antitumor efficiency and reducing its toxicity. We reported that hyaluronic acid (HA)-coated chitosan NPs promoted the drug delivery of 5-fluorouracil (5-Fu) into tumor cells that highly expressed CD44. Our new findings suggested that HA-coated chitosan NPs enhanced drug accumulation by effectively transporting NPs into CD44-overexpressed tumor cells, and they also resulted in mitochondrial damage induced by the production of reactive oxygen species (ROS). Compared to free drug and uncoated NPs, HA-coated chitosan NPs exhibited stronger inhibition rates and induced obvious apoptosis in CD44-overexpressed A549 cells. Biocompatible and biodegradable HA-coated chitosan NPs were developed to encapsulate a chemotherapeutic drug (5-Fu) to enhance drug accumulation in tumor cells and to improve the agent's antitumor efficiency by offering targeted drug delivery via CD44.

  13. Utilization of the natural helper model in health promotion targeting African American men.

    PubMed

    Scott, Tiffany N

    2009-12-01

    When compared with other racial and ethnic groups, African American men experience a great number of health disparities. The factors that perpetuate health disparities among African American men are multidimensional and include lack of access to equitable health care, lack of knowledge and limited education about health promoting behaviors, lack of organizational trust and acceptability, the impact of masculinity on health, and psychological factors. This article explores the health promotion needs of African American men and the ability of the natural helper model to address those needs. Further discussion of its use by holistic nurses as a culturally tailored health promotion intervention targeting African American men is presented.

  14. Interaction research on an antiviral molecule that targets the coat protein of southern rice black-streaked dwarf virus.

    PubMed

    Ran, Longlu; Ding, Yan; Luo, Liangzhi; Gan, Xiuhai; Li, Xiangyang; Chen, Yongzhong; Hu, Deyu; Song, Baoan

    2017-10-01

    Southern rice black-streaked dwarf virus (SRBSDV) coat protein (P10) is the key protein required for viral transmission and host plant infection and is thus a promising target for anti-SRBSDV agent screening. In this study, P10 was obtained from Escherichia coli through cloning, expression, and purification. The antiviral agent Ningnanmycin was selected as control, and a series of antiviral compounds based on the structural scaffold of ferulic acid were analyzed. Size-exclusion chromatography analysis results showed that compound F27 can alter the aggregation of P10 proteins. Furthermore, fluorescence titration and microscale thermophoresis assay results indicated that F27 binds to P10 with KA of 5.75×10(5)M(-1) and KD of 7.81μM. The ligand- and receptor-based three-dimensional quantitative structure-activity analyses were performed to determine the requirements for the interaction between the carboxyl structures and P10s. On the basis of the obtained models and information, we provided insights regarding the design and optimization of novel molecules as anti-SRBSDV agents. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Physical and chemical characterization of Ag-doped Ti coatings produced by magnetron sputtering of modular targets.

    PubMed

    Schmitz, Tobias; Warmuth, Franziska; Werner, Ewald; Hertl, Cornelia; Groll, Jürgen; Gbureck, Uwe; Moseke, Claus

    2014-11-01

    Silver-doped Ti films were produced using a single magnetron sputtering source equipped with a titanium target containing implemented silver modules under variation of bias voltage and substrate temperature. The Ti(Ag) films were characterized regarding their morphology, contact angle, phase composition, silver content and distribution as well as the elution of Ag(+) ions into cell media. SEM and AFM pictures showed that substrate heating during film deposition supported the formation of even and dense surface layers with small roughness values, an effect that could even be enforced, when a substrate bias voltage was applied instead. The deposition of both Ti and Ag was confirmed by X-ray diffraction. ICP-MS and EDX showed a clear correlation between the applied sputtering parameters and the silver content of the coatings. Surface-sensitive XPS measurements revealed that higher substrate temperatures led to an accumulation of Ag in the near-surface region, while the application of a bias voltage had the opposite effect. Additional elution measurements using ICP-MS showed that the release kinetics depended on the amount of silver located at the film surface and hence could be tailored by variation of the sputter parameters.

  16. Paclitaxel-coated balloon reduces target lesion revascularization compared with standard balloon angioplasty.

    PubMed

    Candy, Nicholas; Ng, Eugene; Velu, Ramesh

    2017-02-01

    Peripheral arterial disease (PAD) is a highly prevalent condition that contributes significantly to the morbidity and mortality of affected patients. PAD creates a significant economic burden on health care systems around the world. We reviewed all available literature to provide a meta-analysis assessing the outcome of patients treated with drug-eluting balloons (DEBs) compared with percutaneous transluminal balloon angioplasty (PTA) through measuring the rate of target lesion revascularization (TLR). An electronic search of the MEDLINE, Scopus, Embase, Web of Science, and Cochrane Library databases was performed. Articles reporting randomized controlled trials that compared treatment with DEBs vs PTA were selected for inclusion. A meta-analysis was performed by pooling data on rates of TLR, binary restenosis (BR), and late lumen loss (LLL). The 10 included articles comprised a sample size of 1292 patients. Meta-analysis demonstrated the rate of TLR in DEB-treated patients was significantly lower compared with patients treated with PTA at 6 months (odds ratio [OR], 0.24; 95% confidence interval [CI], 0.11-0.53; P = .0004), 12 months (OR, 0.28; 95% CI, 0.13-0.62; P = .002), and 24 months (OR, 0.25; 95% CI, 0.10-0.61; P = .002). Decreased LLL and BR was demonstrated at 6 months in patients treated with DEBs compared with patients treated with PTA (mean difference, -0.74; 95% CI, -0.97 to -0.51; P = .00001; OR, 0.34; 95% CI, 0.23-0.49; P = .00001). This meta-analysis demonstrates that treatment with DEBs compared with PTA results in reduced rates of reintervention in patients with PAD. Comparison of DEBs to other emerging treatments to determine which method results in the lowest reintervention rates and in the greatest improvement in quality of life should be the focus of future trials. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  17. Multigene knockout utilizing off-target mutations of the CRISPR/Cas9 system in rice.

    PubMed

    Endo, Masaki; Mikami, Masafumi; Toki, Seiichi

    2015-01-01

    The clustered regularly interspaced short palindromic repeat (CRISPR)-associated endonuclease 9 (CRISPR/Cas9) system has been demonstrated to be a robust genome engineering tool in a variety of organisms including plants. However, it has been shown that the CRISPR/Cas9 system cleaves genomic DNA sequences containing mismatches to the guide RNA strand. We expected that this low specificity could be exploited to induce multihomeologous and multiparalogous gene knockouts. In the case of polyploid plants, simultaneous modification of multiple homeologous genes, i.e. genes with similar but not identical DNA sequences, is often needed to obtain a desired phenotype. Even in diploid plants, disruption of multiparalogous genes, which have functional redundancy, is often needed. To validate the applicability of the CRISPR/Cas9 system to target mutagenesis of paralogous genes in rice, we designed a single-guide RNA (sgRNA) that recognized 20 bp sequences of cyclin-dependent kinase B2 (CDKB2) as an on-target locus. These 20 bp possess similarity to other rice CDK genes (CDKA1, CDKA2 and CDKB1) with different numbers of mismatches. We analyzed mutations in these four CDK genes in plants regenerated from Cas9/sgRNA-transformed calli and revealed that single, double and triple mutants of CDKA2, CDKB1 and CDKB2 can be created by a single sgRNA. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  18. Sensing device and method for measuring emission time delay during irradiation of targeted samples utilizing variable phase tracking

    NASA Technical Reports Server (NTRS)

    Danielson, J. D. Sheldon (Inventor)

    2006-01-01

    An apparatus for measuring emission time delay during irradiation of targeted samples by utilizing digital signal processing to determine the emission phase shift caused by the sample is disclosed. The apparatus includes a source of electromagnetic radiation adapted to irradiate a target sample. A mechanism generates first and second digital input signals of known frequencies with a known phase relationship, and a device then converts the first and second digital input signals to analog sinusoidal signals. An element is provided to direct the first input signal to the electromagnetic radiation source to modulate the source by the frequency thereof to irradiate the target sample and generate a target sample emission. A device detects the target sample emission and produces a corresponding first output signal having a phase shift relative to the phase of the first input signal, the phase shift being caused by the irradiation time delay in the sample. A member produces a known phase shift in the second input signal to create a second output signal. A mechanism is then provided for converting each of the first and second analog output signals to digital signals. A mixer receives the first and second digital output signals and compares the signal phase relationship therebetween to produce a signal indicative of the change in phase relationship between the first and second output signals caused by the target sample emission. Finally, a feedback arrangement alters the phase of the second input signal based on the mixer signal to ultimately place the first and second output signals in quadrature. Mechanisms for enhancing this phase comparison and adjustment technique are also disclosed.

  19. Self-Assembly of an Optically-Responsive Polydiacetylene-Coating on Iron Ferrite Magnetic Nanoparticles for Tumor Detection and Targeting

    NASA Astrophysics Data System (ADS)

    Le, Vivian

    Nanoparticles are a promising diagnostic agent with applications in tumor imaging and targeted cancer treatment. They can offer multifunctional properties by combining imaging methods to improve cancer diagnosis, treatment, and disease monitoring. Two such complementary tools are magnetic resonance imaging (MRI) and fluorescence imaging. In this thesis, a dual solvent exchange approach was chosen to facilitate the self-assembly of amphiphilic diacetylene monomers onto hydrophobic iron ferrite magnetic nanoparticles (MNPs). Various concentrations of the diacetylene monomers, 10,12-pentacosadiynoic acid (PCDA) and 10,12-heptacosadiynoic acid (HCDA), were coated onto ˜14 nm iron ferrite MNPs. The diacetylene monomer coating were cross-linked to a stable blue colored polydiacetylene (PDA) coating after applying UV light. The resulting PDA-MNP hybrid displayed characteristic chromogenic and fluorogenic in response to thermal stress. This novel multifunctional nanoparticle system holds exciting potential for dual-modality diagnostics applications.

  20. Improving sensitivity and specificity of capturing and detecting targeted cancer cells with anti-biofouling polymer coated magnetic iron oxide nanoparticles.

    PubMed

    Lin, Run; Li, Yuancheng; MacDonald, Tobey; Wu, Hui; Provenzale, James; Peng, Xingui; Huang, Jing; Wang, Liya; Wang, Andrew Y; Yang, Jianyong; Mao, Hui

    2017-02-01

    Detecting circulating tumor cells (CTCs) with high sensitivity and specificity is critical to management of metastatic cancers. Although immuno-magnetic technology for in vitro detection of CTCs has shown promising potential for clinical applications, the biofouling effect, i.e., non-specific adhesion of biomolecules and non-cancerous cells in complex biological samples to the surface of a device/probe, can reduce the sensitivity and specificity of cell detection. Reported herein is the application of anti-biofouling polyethylene glycol-block-allyl glycidyl ether copolymer (PEG-b-AGE) coated iron oxide nanoparticles (IONPs) to improve the separation of targeted tumor cells from aqueous phase in an external magnetic field. PEG-b-AGE coated IONPs conjugated with transferrin (Tf) exhibited significant anti-biofouling properties against non-specific protein adsorption and off-target cell uptake, thus substantially enhancing the ability to target and separate transferrin receptor (TfR) over-expressed D556 medulloblastoma cells. Tf conjugated PEG-b-AGE coated IONPs exhibited a high capture rate of targeted tumor cells (D556 medulloblastoma cell) in cell media (58.7±6.4%) when separating 100 targeted tumor cells from 1×10(5) non-targeted cells and 41 targeted tumor cells from 100 D556 medulloblastoma cells spiked into 1mL blood. It is demonstrated that developed nanoparticle has higher efficiency in capturing targeted cells than widely used micron-sized particles (i.e., Dynabeads(®)). Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Sensitivity control of optical fiber biosensors utilizing turnaround point long period gratings with self-assembled polymer coatings

    NASA Astrophysics Data System (ADS)

    Gifford, Erika; Wang, Z.; Ramachandran, S.; Heflin, J. R.

    2007-09-01

    Ionic self-assembled multilayers (ISAMs) adsorbed on long period fiber gratings (LPGs) can serve as an inexpensive, robust, portable, biosensor platform. The ISAM technique is a layer-by-layer deposition technique that creates thin films on the nanoscale level. The combination of ISAMs with LPGs yields exceptional sensitivity of the optical fiber transmission spectrum. We have shown theoretically that the resonant wavelength shift for a thin-film coated LPG can be caused by the variation of the film's refractive index and/or the variation of the thickness of the film. We have experimentally demonstrated that the deposition of nm-thick ISAM films on LPGs induces shifts in the resonant wavelength of > 1.6 nm per nm of thin film. It has also been shown that the sensitivity of the LPG to the thickness of the ISAM film increases with increased film thickness. We have further demonstrated that ISAM-coated LPGs can function effectively as biosensors by using the biotin-streptavidin system and by using the Bacillus anthracis (Anthrax) antibody- PA (Protective Antigen) system. Experiments have been successfully performed in both air and solution, which illustrates the versatility of the biosensor. The results confirm that ISAM-LPGs yield a reusable, thermally-stable, and robust platform for designing and building efficient optical biosensors.

  2. Utilization of Glycosaminoglycans/Proteoglycans as Carriers for Targeted Therapy Delivery

    PubMed Central

    Misra, Suniti; Hascall, Vincent C.; Atanelishvili, Ilia; Moreno Rodriguez, Ricardo; Markwald, Roger R.; Ghatak, Shibnath

    2015-01-01

    The outcome of patients with cancer has improved significantly in the past decade with the incorporation of drugs targeting cell surface adhesive receptors, receptor tyrosine kinases, and modulation of several molecules of extracellular matrices (ECMs), the complex composite of collagens, glycoproteins, proteoglycans, and glycosaminoglycans that dictates tissue architecture. Cancer tissue invasive processes progress by various oncogenic strategies, including interfering with ECM molecules and their interactions with invasive cells. In this review, we describe how the ECM components, proteoglycans and glycosaminoglycans, influence tumor cell signaling. In particular this review describes how the glycosaminoglycan hyaluronan (HA) and its major receptor CD44 impact invasive behavior of tumor cells, and provides useful insight when designing new therapeutic strategies in the treatment of cancer. PMID:26448753

  3. Safety and efficacy of targeted hyperthermia treatment utilizing gold nanorod therapy in spontaneous canine neoplasia.

    PubMed

    Schuh, Elizabeth M; Portela, Roberta; Gardner, Heather L; Schoen, Christian; London, Cheryl A

    2017-10-02

    Hyperthermia is an established anti-cancer treatment but is limited by tolerance of adjacent normal tissues. Parenteral administration of gold nanorods (NRs) as a photosensitizer amplifies the effects of hyperthermia treatment while sparing normal tissues. This therapy is well tolerated and has demonstrated anti-tumor effects in mouse models. The purpose of this phase 1 study was to establish the safety and observe the anti-tumor impact of gold NR enhanced (plasmonic) photothermal therapy (PPTT) in client owned canine patients diagnosed with spontaneous neoplasia. Seven dogs underwent gold NR administration and subsequent NIR PPTT. Side effects were mild and limited to local reactions to NIR laser. All of the dogs enrolled in the study experienced stable disease, partial remission or complete remission. The overall response rate (ORR) was 28.6% with partial or complete remission of tumors at study end. PPTT utilizing gold nanorod therapy can be safely administered to canine patients. Further studies are needed to determine the true efficacy in a larger population of canine cancer patients and to and identify those patients most likely to benefit from this therapy.

  4. Utility of the dual-specificity protein kinase TTK as a therapeutic target for intrahepatic spread of liver cancer

    PubMed Central

    Miao, Ruoyu; Wu, Yan; Zhang, Haohai; Zhou, Huandi; Sun, Xiaofeng; Csizmadia, Eva; He, Lian; Zhao, Yi; Jiang, Chengyu; Miksad, Rebecca A.; Ghaziani, Tahereh; Robson, Simon C.; Zhao, Haitao

    2016-01-01

    Therapies for primary liver cancer, the third leading cause of cancer-related death worldwide, remain limited. Following multi-omics analysis (including whole genome and transcriptome sequencing), we were able to identify the dual-specific protein kinase TTK as a putative new prognostic biomarker for liver cancer. Herein, we show that levels of TTK protein are significantly elevated in neoplastic tissues from a cohort of liver cancer patients, when compared with adjacent hepatic tissues. We also tested the utility of TTK targeted inhibition and have demonstrated therapeutic potential in an experimental model of liver cancer in vivo. Following lentiviral shRNA knockdown in several human liver cancer cell lines, we demonstrated that TTK boosts cell growth and promotes cell spreading; as well as protects against senescence and decreases autophagy. In an experimental animal model, we show that in vitro knockdown of TTK effectively blocks intrahepatic growth of human HCC xenografts. Furthermore, we note that, in vivo silencing of TTK, by systemically delivering TTK siRNAs to already tumor-bearing liver, limits intrahepatic spread of liver cancer cells. This intervention is associated with decreased tumor aggressiveness, as well as increased senescence and autophagy. Taken together, our data suggest that targeted TTK inhibition might have clinical utility as an adjunct therapy in management of liver cancer. PMID:27618777

  5. Design and construction of multifunctional hyperbranched polymers coated magnetite nanoparticles for both targeting magnetic resonance imaging and cancer therapy.

    PubMed

    Mashhadi Malekzadeh, Asemeh; Ramazani, Ali; Tabatabaei Rezaei, Seyed Jamal; Niknejad, Hassan

    2017-03-15

    Magnetic drug targeting is a drug delivery strategy that can be used to improve the therapeutic efficiency on tumor cells and reduce the side effects on normal cells and tissues. The aim in this study is designing a novel multifunctional drug delivery system based on superparamagnetic nanoparticles for cancer therapy. Magnetic nanoparticles were synthesized by coprecipitation of iron oxide followed by coating with poly citric acid (PCA) dendritic macromolecules via bulk polymerization strategy. It was further surface-functionalized with poly(ethylene glycol) (PEG) and then to achieve tumor cell targeting property, folic acid was further incorporated to the surface of prepared carriers via a facile coupling reaction between the hydroxyl end group of the PEG and the carboxyl group of folic acid. The so prepared nanocarriers (Fe3O4@PCA-PEG-FA) were characterized by X-ray diffraction, TEM, TGA, FT-IR, DLS and VSM techniques. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. Transmission electron microscopy and dynamic light scattering were also performed which revealed that size of nanocarriers was lying in the range of 10-49nm. Quercetin loading and release profiles of prepared nanocarriers showed that up to 83% of loaded drug was released in 250h. Fluorescent microscopy showed that the cellular uptake by folate receptor-overexpressing HeLa cells of the quercetin-loaded Fe3O4@PCA-PEG-FA nanoparticles was higher than that of non-folate conjugated nanoparticles. Thus, folate conjugation significantly increased nanoparticle cytotoxicity. Also, T2-weighted MRI images of Fe3O4@PCA-PEG-FA nanoparticles showed that the magnetic resonance signal is enhanced significantly with increasing nanoparticle concentration in water and they also served as MRI contrast agents with relaxivities of 3.4mM(-1)s(-1) (r1) and 99.8mM(-1)s(-1) (r2). The results indicate that this multifunctional nanocarrier is a significant breakthrough in developing a

  6. Characterization of xylan utilization and discovery of a new endoxylanase in Thermoanaerobacterium saccharolyticum through targeted gene deletions

    SciTech Connect

    Podkaminer, Kara K; Guss, Adam M; McKenzie, Heather; Hogsett, David; Lynd, Lee R

    2012-01-01

    The economical production of fuels and commodity chemicals from lignocellulose requires the utilization of both the cellulose and hemicellulose fractions. Xylanase enzymes allow greater utilization of hemicellulose while also increasing cellulose hydrolysis. Recent metabolic engineering efforts have resulted in a strain of Thermoanaerobacterium saccharolyticum that can convert C(5) and C(6) sugars, as well as insoluble xylan, into ethanol at high yield. To better understand the process of xylan solubilization in this organism, a series of targeted deletions were constructed in the homoethanologenic T. saccharolyticum strain M0355 to characterize xylan hydrolysis and xylose utilization in this organism. While the deletion of -xylosidase xylD slowed the growth of T. saccharolyticum on birchwood xylan and led to an accumulation of short-chain xylo-oligomers, no other single deletion, including the deletion of the previously characterized endoxylanase XynA, had a phenotype distinct from that of the wild type. This result indicates a multiplicity of xylanase enzymes which facilitate xylan degradation in T. saccharolyticum. Growth on xylan was prevented only when a previously uncharacterized endoxylanase encoded by xynC was also deleted in conjunction with xynA. Sequence analysis of xynC indicates that this enzyme, a low-molecular-weight endoxylanase with homology to glycoside hydrolase family 11 enzymes, is secreted yet untethered to the cell wall. Together, these observations expand our understanding of the enzymatic basis of xylan hydrolysis by T. saccharolyticum.

  7. Animal models and therapeutic molecular targets of cancer: utility and limitations.

    PubMed

    Cekanova, Maria; Rathore, Kusum

    2014-01-01

    Cancer is the term used to describe over 100 diseases that share several common hallmarks. Despite prevention, early detection, and novel therapies, cancer is still the second leading cause of death in the USA. Successful bench-to-bedside translation of basic scientific findings about cancer into therapeutic interventions for patients depends on the selection of appropriate animal experimental models. Cancer research uses animal and human cancer cell lines in vitro to study biochemical pathways in these cancer cells. In this review, we summarize the important animal models of cancer with focus on their advantages and limitations. Mouse cancer models are well known, and are frequently used for cancer research. Rodent models have revolutionized our ability to study gene and protein functions in vivo and to better understand their molecular pathways and mechanisms. Xenograft and chemically or genetically induced mouse cancers are the most commonly used rodent cancer models. Companion animals with spontaneous neoplasms are still an underexploited tool for making rapid advances in human and veterinary cancer therapies by testing new drugs and delivery systems that have shown promise in vitro and in vivo in mouse models. Companion animals have a relatively high incidence of cancers, with biological behavior, response to therapy, and response to cytotoxic agents similar to those in humans. Shorter overall lifespan and more rapid disease progression are factors contributing to the advantages of a companion animal model. In addition, the current focus is on discovering molecular targets for new therapeutic drugs to improve survival and quality of life in cancer patients.

  8. Using a targeting metric to predict the utility of an EO imager as a pilotage aid

    NASA Astrophysics Data System (ADS)

    Vollmerhausen, Richard H.; Bui, Trang

    2006-05-01

    Army aviators use both image intensified goggles and thermal imagers as night vision aids when flying helicopters at night. The Targeting Task Performance (TTP) metric can be used to predict how well these imagers support the pilotage task under different illumination and thermal contrast conditions. The TTP metric predicts the field performance of the Aviator's Night Vision Imaging System, the Apache Helicopter Pilot's Night Vision System, and the Advanced Helicopter Pilotage system. These three systems represent diverse technologies: image intensified goggles, a first generation thermal imager, and a second-generation thermal imager. The ability of the TTP metric to predict the behavior of these diverse systems is evidence of its suitability as a pilotage metric. This paper discusses the application of the TTP metric to helicopter pilotage. Data from field surveys of Army aviators are used to validate the use of the TTP metric to predict pilotage system performance. Since knowledge of scene contrast is necessary to make sensor design trades using the TTP metric, a discussion of the terrain thermal contrast available in the mid-wave and long-wave infrared is also provided.

  9. Utilizing polymer-coated vials to illustrate the fugacity and bioavailability of chlorinated pesticide residues in contaminated soils

    USDA-ARS?s Scientific Manuscript database

    Fugacity and bioavailability concepts can be challenging topics to communicate effectively in the timeframe of an academic laboratory course setting. In this experiment, students observe partitioning of the residues over time into an artificial biological matrix. The three compounds utilized are o...

  10. Animal models and therapeutic molecular targets of cancer: utility and limitations

    PubMed Central

    Cekanova, Maria; Rathore, Kusum

    2014-01-01

    Cancer is the term used to describe over 100 diseases that share several common hallmarks. Despite prevention, early detection, and novel therapies, cancer is still the second leading cause of death in the USA. Successful bench-to-bedside translation of basic scientific findings about cancer into therapeutic interventions for patients depends on the selection of appropriate animal experimental models. Cancer research uses animal and human cancer cell lines in vitro to study biochemical pathways in these cancer cells. In this review, we summarize the important animal models of cancer with focus on their advantages and limitations. Mouse cancer models are well known, and are frequently used for cancer research. Rodent models have revolutionized our ability to study gene and protein functions in vivo and to better understand their molecular pathways and mechanisms. Xenograft and chemically or genetically induced mouse cancers are the most commonly used rodent cancer models. Companion animals with spontaneous neoplasms are still an underexploited tool for making rapid advances in human and veterinary cancer therapies by testing new drugs and delivery systems that have shown promise in vitro and in vivo in mouse models. Companion animals have a relatively high incidence of cancers, with biological behavior, response to therapy, and response to cytotoxic agents similar to those in humans. Shorter overall lifespan and more rapid disease progression are factors contributing to the advantages of a companion animal model. In addition, the current focus is on discovering molecular targets for new therapeutic drugs to improve survival and quality of life in cancer patients. PMID:25342884

  11. The opportunistic pathogen Serratia marcescens utilizes type VI secretion to target bacterial competitors.

    PubMed

    Murdoch, Sarah L; Trunk, Katharina; English, Grant; Fritsch, Maximilian J; Pourkarimi, Ehsan; Coulthurst, Sarah J

    2011-11-01

    The type VI secretion system (T6SS) is the most recently described and least understood of the protein secretion systems of Gram-negative bacteria. It is widely distributed and has been implicated in the virulence of various pathogens, but its mechanism and exact mode of action remain to be defined. Additionally there have been several very recent reports that some T6SSs can target bacteria rather than eukaryotic cells. Serratia marcescens is an opportunistic enteric pathogen, a class of bacteria responsible for a significant proportion of hospital-acquired infections. We describe the identification of a functional T6SS in S. marcescens strain Db10, the first report of type VI secretion by an opportunist enteric bacterium. The T6SS of S. marcescens Db10 is active, with secretion of Hcp to the culture medium readily detected, and is expressed constitutively under normal growth conditions from a large transcriptional unit. Expression of the T6SS genes did not appear to be dependent on the integrity of the T6SS. The S. marcescens Db10 T6SS is not required for virulence in three nonmammalian virulence models. It does, however, exhibit dramatic antibacterial killing activity against several other bacterial species and is required for S. marcescens to persist in a mixed culture with another opportunist pathogen, Enterobacter cloacae. Importantly, this antibacterial killing activity is highly strain specific, with the S. marcescens Db10 T6SS being highly effective against another strain of S. marcescens with a very similar and active T6SS. We conclude that type VI secretion plays a crucial role in the competitiveness, and thus indirectly the virulence, of S. marcescens and other opportunistic bacterial pathogens.

  12. Antheraea pernyi silk fibroin-coated PEI/DNA complexes for targeted gene delivery in HEK 293 and HCT 116 cells.

    PubMed

    Liu, Yu; You, Renchuan; Liu, Guiyang; Li, Xiufang; Sheng, Weihua; Yang, Jicheng; Li, Mingzhong

    2014-04-25

    Polyethylenimine (PEI) has attracted much attention as a DNA condenser, but its toxicity and non-specific targeting limit its potential. To overcome these limitations, Antheraea pernyi silk fibroin (ASF), a natural protein rich in arginyl-glycyl-aspartic acid (RGD) peptides that contains negative surface charges in a neutral aqueous solution, was used to coat PEI/DNA complexes to form ASF/PEI/DNA ternary complexes. Coating these complexes with ASF caused fewer surface charges and greater size compared with the PEI/DNA complexes alone. In vitro transfection studies revealed that incorporation of ASF led to greater transfection efficiencies in both HEK (human embryonic kidney) 293 and HCT (human colorectal carcinoma) 116 cells, albeit with less electrostatic binding affinity for the cells. Moreover, the transfection efficiency in the HCT 116 cells was higher than that in the HEK 293 cells under the same conditions, which may be due to the target bonding affinity of the RGD peptides in ASF for integrins on the HCT 116 cell surface. This result indicated that the RGD binding affinity in ASF for integrins can enhance the specific targeting affinity to compensate for the reduction in electrostatic binding between ASF-coated PEI carriers and cells. Cell viability measurements showed higher cell viability after transfection of ASF/PEI/DNA ternary complexes than after transfection of PEI/DNA binary complexes alone. Lactate dehydrogenase (LDH) release studies further confirmed the improvement in the targeting effect of ASF/PEI/DNA ternary complexes to cells. These results suggest that ASF-coated PEI is a preferred transfection reagent and useful for improving both the transfection efficiency and cell viability of PEI-based nonviral vectors.

  13. Membrane electrode assembly with enhanced platinum utilization for high temperature proton exchange membrane fuel cell prepared by catalyst coating membrane method

    NASA Astrophysics Data System (ADS)

    Liang, Huagen; Su, Huaneng; Pollet, Bruno G.; Linkov, Vladimir; Pasupathi, Sivakumar

    2014-11-01

    In this work, membrane electrode assemblies (MEAs) prepared by catalyst coating membrane (CCM) method are investigated for reduced platinum (Pt) loading and improved Pt utilization of high temperature proton exchange membrane fuel cell (PEMFC) based on phosphoric acid (PA)-doped poly(2,5-benzimidazole) (AB-PBI) membrane. The results show that CCM method exhibits significantly higher cell performance and Pt-specific power density than that of MEAs prepared with conventional gas diffusion electrode (GDE) under a low Pt loading level. In-suit cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) show that the MEAs prepared by the CCM method have a higher electrochemical surface area (ECSA), low cell ohmic resistance and low charge transfer resistance as compared to those prepared with GDEs at the same Pt loading.

  14. The white coat effect is not associated with additional increase of target organ damage in true resistant hypertension.

    PubMed

    Figueiredo, Valéria Nasser; Martins, Luiz Cláudio; Boer-Martins, Leandro; Cabral de Faria, Ana Paula; de Haro Moraes, Carolina; Cardoso Santos, Rodrigo; Nogueira, Armando R; Moreno, Heitor

    2013-01-05

    White coat effect (WCE) (i.e., the difference between office blood pressure [OBP] and awake ambulatory blood pressure monitoring [ABPM]) may be present in hypertensive individuals. The relationship between occurrence of WCE and target organ damage (TOD) has not yet been assessed in true resistant hypertension (RHTN). RHTN patients were divided into two groups: RHTN with WCE (WCE, n=66) and RHTN without WCE (non-WCE, n=61). All patients were submitted to OBP measurement, ABPM, echocardiography and renal function evaluation in three visits. No differences were observed between the WCE and non-WCE groups regarding age, body mass index or gender. OBP were 169.8±15.8/95.1±14.0 (WCE) and 161.9±9.0/90.1±10.4mmHg (non-WCE), ABPM=143.0±12.8/86.1±9.9 (WCE) and 146.1±13.6/85.1±14.9mmHg (non-WCE). No statistical differences were observed between WCE and non-WCE subgroups with respect to left ventricular mass index (LVMI) (WCE=131±4.7; non-WCE=125±2.9g/m(2)), creatinine clearance (WCE=78±4.7; non-WCE=80±3.6ml/min/m(2)) and microalbuminuria (MA) (WCE=44±8.4; non-WCE=49±6.8mg/g Cr). This finding may suggest that WCE is not associated with additional increase of TOD in true RHTN subjects. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  15. Radiographic detection of 100 A thickness variations in 1-. mu. m-thick coatings applied to submillimeter-diameter laser fusion targets

    SciTech Connect

    Stupin, D.M.

    1986-01-01

    We have developed x-ray radiography to measure thickness variations of coatings on laser fusion targets. Our technique is based on measuring the variation in x-ray transmission through the targets. The simplest targets are hollow glass microshells or microballoons 100 to 500 ..mu..m in diameter, that have several layers of metals or plastics, 1 to 100 ..mu..m thick. Our goal is to examine these opaque coatings for thickness variations as small as 1% or 0.1%, depending on the type of defect. Using contact radiography we have obtained the desired sensitivity for concentric and elliptical defects of 1%. This percentage corresponds to thickness variations as small as 100 A in a 1-..mu..m-thick coating. For warts and dimples, the desired sensitivity is a function of the area of the defect, and we are developing a system to detect 0.1% thickness variations that cover an area 10 ..mu..m by 10 ..mu..m. We must use computer analysis of contact radiographs to measure 1% thickness variations in either concentricity or ellipticity. Because this analysis takes so long on our minicomputer, we preselect the radiographs by looking for defects at the 10% level on a video image analysis system.

  16. Pharmacokinetic Parameters Determination and In Vitro-In Vivo Correlation of Ileocolonic-Targeted pH-Responsive Coated Mini-Tablets of Naproxen.

    PubMed

    Hadi, Mohd Abdul; Raghavendra Rao, Nidagurthi Guggilla; Srinivasa Rao, Avanapu

    2015-01-01

    This research work aims to determine the pharmacokinetic parameters and in vitro-in vivo correlation of the selected ileocolonic-targeted coated mini-tablet filled capsule formulation of naproxen. The pure suspension and coated mini-tablet filled capsule formulation of naproxen were administered to adult albino rabbits through the oral route. The samples were analyzed for naproxen by an HPLC method. For the pure drug suspension, the peak plasma concentration was found as 8.499±0.029 μg/ml at 1.139±0.010 hours and the half-life was found to be 9.459±0.387 hours, whereas for the formulation the peak plasma concentration was found as 6.814±0.037 μg/ml at 8.042±0.069 hours and the half-life was found to be 19.657±0.359 hours. This decreased the peak plasma concentration at a delayed time and increased the half-life of the capsule formulation in comparison with the pure drug suspension which showed that naproxen was only targeted to the ileocolonic region. A significant in vitro-in vivo correlation (i.e. R(2)=0.9901) was also obtained. Thus, the results of these findings suggest that naproxen formulated as coated mini-tablets can be suitable for targeted ileocolonic drug delivery.

  17. Roll-to-roll cohesive, coated, flexible, high-efficiency polymer light-emitting diodes utilizing ITO-free polymer anodes.

    PubMed

    Shin, Seongbeom; Yang, Minyang; Guo, L Jay; Youn, Hongseok

    2013-12-09

    This paper reports solution-processed, high-efficiency polymer light-emitting diodes fabricated by a new type of roll-to-roll coating method under ambient air conditions. A noble roll-to-roll cohesive coating system utilizes only natural gravity and the surface tension of the solution to flow out from the capillary to the surface of the substrate. Because this mechanism uses a minimally cohesive solution, the roll-to-roll cohesive coating can effectively realize an ultra-thin film thickness for the electron injection layer. In addition, the roll-to-roll cohesive coating enables the fabrication of a thicker polymer anode film more than 250 nm at one time by modification of the surface energy and without wasting the solution. It is observed that the standard sheet resistance deviation of the polymer anode is only 2.32 Ω/□ over 50 000 bending cycles. The standard sheet resistance deviation of the polymer anode in the different bending angles (0 to 180°) is 0.313 Ω/□, but the case of the ITO-PET is 104.93 Ω/□. The average surface roughness of the polymer anode measured by atomic force microscopy is only 1.06 nm. Because the surface of the polymer anode has a better quality, the leakage current of the polymer light-emitting diodes (PLEDs) using the polymer anode is much lower than that using the ITO-PET substrate. The luminous power efficiency of the two devices is 4.13 lm/W for the polymer anode and 3.21 lm/W for the ITO-PET. Consequently, the PLEDs made by using the polymer anode exhibited 28% enhanced performance because the polymer anode represents not only a higher transparency than the ITO-PET in the wavelength of 560 nm but also greatly reduced roughness. The optimized the maximum current efficiency and power efficiency of the device show around 6.1 cd/A and 5.1 lm/W, respectively, which is comparable to the case of using the ITO-glass.

  18. Highly efficient colorimetric detection of target cancer cells utilizing superior catalytic activity of graphene oxide-magnetic-platinum nanohybrids

    NASA Astrophysics Data System (ADS)

    Kim, Moon Il; Kim, Min Su; Woo, Min-Ah; Ye, Youngjin; Kang, Kyoung Suk; Lee, Jinwoo; Park, Hyun Gyu

    2014-01-01

    Enzyme-linked immunosorbent assays (ELISAs) have most widely been applied in immunoassays for several decades. However, several unavoidable limitations (e.g., instability caused by structural unfolding) of natural enzymes have hindered their widespread applications. Here, we describe a new nanohybrid consisting of Fe3O4 magnetic nanoparticles (MNPs) and platinum nanoparticles (Pt NPs), simultaneously immobilized on the surface of graphene oxide (GO). By synergistically integrating highly catalytically active Pt NPs and MNPs on GO whose frameworks possess high substrate affinity, the nanohybrid is able to achieve up to a 30-fold higher maximal reaction velocity (Vmax) compared to that of free GO for the colorimetric reaction of the peroxidase substrate, 3,3',5,5'-tetramethylbenzidine (TMB), and enable rapid detection of target cancer cells. Specifically, using this new assay system, clinically important breast cancer cells are detected in a 5 min time period at room temperature with high specificity and sensitivity. The remarkably high capability to catalyze oxidation reactions could allow the nanohybrid to replace conventional peroxidase-based immunoassay systems as part of new, rapid, robust and convenient assay systems which can be widely utilized for the identification of important target molecules.Enzyme-linked immunosorbent assays (ELISAs) have most widely been applied in immunoassays for several decades. However, several unavoidable limitations (e.g., instability caused by structural unfolding) of natural enzymes have hindered their widespread applications. Here, we describe a new nanohybrid consisting of Fe3O4 magnetic nanoparticles (MNPs) and platinum nanoparticles (Pt NPs), simultaneously immobilized on the surface of graphene oxide (GO). By synergistically integrating highly catalytically active Pt NPs and MNPs on GO whose frameworks possess high substrate affinity, the nanohybrid is able to achieve up to a 30-fold higher maximal reaction velocity (Vmax

  19. Determination of chromium (III) in natural water samples utilizing capillary micro-extraction on nanometre zirconium phosphate coating coupled to electrothermal atomic absorbance spectrometry.

    PubMed

    Bai, Xiaohong; Fan, Zhefeng

    2009-02-01

    A simple and sensitive method for the separation of Cr(III) in natural water was developed. The novel method was targeted on extraction of Cr(III) by using a nanometre-scale zirconium phosphate coated capillary tube, and determined by electrothermal atomic absorption spectrometry (ETAAS). The variables influencing the micro-extraction of Cr(III) including pH, sample volume, sample flow rate, eluent volume and eluent flow rate were investigated. Under the optimized conditions, the detection limit (3s) was 0.042 ng mL(-1), and the relative standard deviation (RSD) was 1.5% (c=10 ng mL(-1), n=7). The proposed method was applied to determination of Cr(III) in natural waters.

  20. Targeted synthesis of porous aromatic frameworks and their composites for versatile, facile, efficacious, and durable antibacterial polymer coatings.

    PubMed

    Yuan, Ye; Sun, Fuxing; Zhang, Feng; Ren, Hao; Guo, Mingyi; Cai, Kun; Jing, Xiaofei; Gao, Xue; Zhu, Guangshan

    2013-12-03

    Novel quaternary pyridinium-type porous aromatic frameworks, PAF-50, and their composites, AgCl-PAF-50, have been synthesized to effectively and efficiently inhibit the growth of bacteria. Most importantly, both PAF-50 and AgCl-PAF-50 have excellent compatibility with conventional polymers, which lead to great operation flexibility and versatility for antibactrial coatings on various medical devices simply via solution or spray coating. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Targeting multiple chorismate-utilizing enzymes with a single inhibitor: validation of a three-stage design.

    PubMed

    Ziebart, Kristin T; Dixon, Seth M; Avila, Belem; El-Badri, Mohamed H; Guggenheim, Kathryn G; Kurth, Mark J; Toney, Michael D

    2010-05-13

    Chorismate-utilizing enzymes are attractive antimicrobial drug targets due to their absence in humans and their central role in bacterial survival and virulence. The structural and mechanistic homology of a group of these inspired the goal of discovering inhibitors that target multiple enzymes. Previously, we discovered seven inhibitors of 4-amino-4-deoxychorismate synthase (ADCS) in an on-bead, fluorescent-based screen of a 2304-member one-bead-one-compound combinatorial library. The inhibitors comprise PAYLOAD and COMBI stages, which interact with active site and surface residues, respectively, and are linked by a SPACER stage. These seven compounds, and six derivatives thereof, also inhibit two other enzymes in this family, isochorismate synthase (IS) and anthranilate synthase (AS). The best binding compound inhibits ADCS, IS, and AS with K(i) values of 720, 56, and 80 microM, respectively. Inhibitors with varying SPACER lengths show the original choice of lysine to be optimal. Lastly, inhibition data confirm the PAYLOAD stage directs the inhibitors to the ADCS active site.

  2. Cross-sectional study of ethnic differences in the utility of area deprivation measures to target socioeconomically deprived individuals.

    PubMed

    Baker, Jessica; Mitchell, Richard; Pell, Jill

    2013-05-01

    Area deprivation measures provide a pragmatic tool for targeting public health interventions at socioeconomically deprived individuals. Ethnic minority groups in the UK experience higher levels of socioeconomic deprivation and certain associated diseases than the White population. The aim of this study was to explore ethnic differences in the utility of area deprivation measures as a tool for targeting socioeconomically deprived individuals. We carried out a cross-sectional study using the Health Survey for England 2004. 7208 participants aged 16-64 years from the four largest ethnic groups in England (White, Indian, Pakistani and Black Caribbean) were included. The main outcome measures were percentage agreement, sensitivity and positive predictive value (PPV) of area deprivation, measured using Index of Multiple Deprivation 2004, in relation to individual socioeconomic position (measured by education, occupation, income, housing tenure and car access). We found that levels of both area and individual deprivation were higher in the Pakistani and Black Caribbean groups compared to the White group. Across all measures, agreement was lower in the Pakistani (50.9-63.4%) and Black Caribbean (61.0-70.1%) groups than the White (67.2-82.4%) group. However, sensitivity was higher in the Pakistani (0.56-0.64) and Black Caribbean (0.59-0.66) groups compared to the White group (0.24-0.38) and PPV was at least as high. The results for the Indian group were intermediate. We conclude that, in spite of lower agreement, area deprivation is better at identifying individual deprivation in ethnic minority groups. There was no evidence that area based targeting of public health interventions will disadvantage ethnic minority groups. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Preparation and characterization of glycoprotein-resistant starch complex as a coating material for oral bioadhesive microparticles for colon-targeted polypeptide delivery.

    PubMed

    Situ, Wenbei; Li, Xiaoxi; Liu, Jia; Chen, Ling

    2015-04-29

    For effective oral delivery of polypeptide or protein and enhancement their oral bioavailability, a new resistant starch-glycoprotein complex bioadhesive carrier and an oral colon-targeted bioadhesive delivery microparticle system were developed. A glycoprotein, concanavalin A (Con A), was successfully conjugated to the molecules of resistant starch acetate (RSA), leading to the formation of resistant starch-glycoprotein complex. This Con A-conjugated RSA film as a coating material showed an excellent controlled-release property. In streptozotocin (STZ)-induced type II diabetic rats, the insulin-loaded microparticles coated with this Con A-conjugated RSA film exhibited good hypoglycemic response for keeping the plasma glucose level within the normal range for totally 44-52 h after oral administration with different insulin dosages. Oral glucose tolerance tests indicated that successive oral administration of these colon-targeted bioadhesive microparticles with insulin at a level of 50 IU/kg could achieve a hypoglycemic effect similar to that by injection of insulin at 35 IU/kg. Therefore, the potential of this new Con A-conjugated RSA film-coated microparticle system has been demonstrated to be capable of improving the oral bioavailability of bioactive proteins and peptides.

  4. Target Organ Complications and Cardiovascular Events Associated with Masked Hypertension and White Coat Hypertension: Analysis from the Dallas Heart Study

    PubMed Central

    Tientcheu, Danielle; Ayers, Colby; Das, Sandeep R.; McGuire, Darren K.; de Lemos, James A.; Khera, Amit; Kaplan, Norman; Victor, Ronald; Vongpatanasin, Wanpen

    2015-01-01

    Background Multiple epidemiological studies from Europe and Asia have demonstrated increased cardiovascular risks associated with isolated elevation of home blood pressure (BP) or masked hypertension (MH). Previous studies have not addressed cardiovascular outcomes associated with MH and white coat hypertension (WCH) in the general population in the United States. Objectives The goal of this study was to determine hypertensive target organ damage and adverse cardiovascular outcomes associated with WCH (high clinic BP ≥140/90 mm Hg, normal home BP of <135/85 mm Hg), MH (high home BP ≥135/85 mm Hg, normal clinic BP <140/90 mm Hg), and sustained hypertension (SH, high home and clinic BP) in the Dallas Heart Study, a large, multiethnic probability-based population cohort. Methods We evaluated associations between WCH, MH, SH and aortic pulse wave velocity (APWV) by magnetic resonance imaging; urinary albumin to creatinine ratio (UACR); and cystatin C at study baseline. Then, associations between WCH and MH with incident cardiovascular outcomes (coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death) over a median follow-up period of 9 years were assessed. Results The study cohort comprised 3,027 subjects (50% African Americans). The sample-weighted prevalence of WCH and MH were 3.3% and 17.8%, respectively. Both WCH and MH were independently associated with increased APWV, cystatin C, and UACR. Both WCH and MH were independently associated with higher cardiovascular events compared with the NT group, even after adjustment for traditional cardiovascular risk factors (adjusted HR: 2.09; 95% CI: 1.05 to 4.15 and adjusted HR: 2.03; 95% CI: 1.36 to 3.03, respectively). Conclusions In a multiethnic U.S. population, both WCH and MH were independently associated with increased aortic stiffness, renal injury, and incident cardiovascular events. Because MH is common and associated with an adverse cardiovascular profile, home BP

  5. Comparative binding, endocytosis, and biodistribution of antibodies and antibody-coated carriers for targeted delivery of lysosomal enzymes to ICAM-1 versus transferrin receptor

    PubMed Central

    Papademetriou, Jason; Garnacho, Carmen; Serrano, Daniel; Bhowmick, Tridib; Schuchman, Edward H.; Muro, Silvia

    2012-01-01

    Targeting lysosomal enzymes to receptors involved in transport into and across cells holds promise to enhance peripheral and brain delivery of enzyme replacement therapies for lysosomal storage disorders. Receptors being explored include those associated with clathrin-mediated pathways, yet other pathways seem also viable. Well characterized examples are that of transferrin receptor (TfR) and intercellular adhesion molecule 1 (ICAM-1), involved in iron transport and leukocyte extravasation, respectively. TfR and ICAM-1 support ERT delivery via clathrin- vs. cell adhesion molecule-mediated mechanisms, displaying different valency and size restrictions. To comparatively assess this, we used antibodies vs. larger multivalent antibody-coated carriers and evaluated TfR vs. ICAM-1 binding and endocytosis in endothelial cells, as well as in vivo biodistribution and delivery of a model lysosomal enzyme required in peripheral organs and brain: acid sphingomyelinase (ASM), deficient in types A–B Niemann Pick disease. We found similar binding of antibodies to both receptors under control conditions, with enhanced binding to activated endothelium for ICAM-1, yet only anti-TfR induced endocytosis efficiently. Contrarily, antibody-coated carriers showed enhanced binding, engulfment, and endocytosis for ICAM-1. In mice, anti-TfR enhanced brain targeting over anti-ICAM, with an opposite outcome in the lungs, while carriers enhanced ICAM-1 targeting over TfR in both organs. Both targeted carriers enhanced ASM delivery to the brain and lungs vs. free ASM, with greater enhancement for anti-ICAM carriers. Therefore, targeting TfR or ICAM-1 improves lysosomal enzyme delivery. Yet, TfR targeting may be more efficient for smaller conjugates or fusion proteins, while ICAM-1 targeting seems superior for multivalent carrier formulations. PMID:22968581

  6. Physicochemical characterization of chitosan-hyaluronan-coated solid lipid nanoparticles for the targeted delivery of paclitaxel: a proof-of-concept study in breast cancer cells.

    PubMed

    Campos, Javier; Varas-Godoy, Manuel; Haidar, Ziyad Samir

    2017-03-01

    To investigate the potential of modified solid lipid nanoparticles (SLN) for the delivery of paclitaxel (PAX). SLN loaded with PAX were prepared via modified high-pressure hot homogenization. Formulation parameters were optimized to obtain a high-quality delivery system. SLN cores were coated, layer-by-layer, with a chitosan and hyaluronan (HA) shell. Selectivity toward HA receptors was tested in a breast cancer cell line, MCF-7. Stable and reproducible nano-sized and negatively charged nanoparticles resulted. Findings reveal that chitosan-HA-coated SLN facilitated the targeting, cellular uptake and the time-/dose-controlled delivery and release of PAX, enhancing intrinsic chemotherapeutic activities. SLN are suitable carrier candidates for nano-oncology given their localized, and potent cytotoxic potential overcoming multidrug-resistant cancer cells.

  7. Development and clinical utility of a novel diagnostic nystagmus gene panel using targeted next-generation sequencing.

    PubMed

    Thomas, Mervyn G; Maconachie, Gail DE; Sheth, Viral; McLean, Rebecca J; Gottlob, Irene

    2017-04-05

    Infantile nystagmus (IN) is a genetically heterogeneous disorder arising from variants of genes expressed within the developing retina and brain. IN presents a diagnostic challenge and patients often undergo numerous investigations. We aimed to develop and assess the utility of a next-generation sequencing (NGS) panel to enhance the diagnosis of IN. We identified 336 genes associated with IN from the literature and OMIM. NimbleGen Human custom array was used to enrich the target genes and sequencing was performed using HiSeq2000. Using reference genome material (NA12878), we show the sensitivity (98.5%) and specificity (99.9%) of the panel. Fifteen patients with familial IN were sequenced using the panel. Two authors were masked to the clinical diagnosis. We identified variants in 12/15 patients in the following genes: FRMD7 (n=3), CACNA1F (n=2), TYR (n=5), CRYBA1 (n=1) and TYRP1 (n=1). In 9/12 patients, the clinical diagnosis was consistent with the genetic diagnosis. In 3/12 patients, the results from the genetic diagnoses (TYR, CRYBA1 and TYRP1 variants) enabled revision of clinical diagnoses. In 3/15 patients, we were unable to determine a genetic diagnosis. In one patient, copy number variation analysis revealed a FRMD7 deletion. This is the first study establishing the clinical utility of a diagnostic NGS panel for IN. We show that the panel has high sensitivity and specificity. The genetic information from the panel will lead to personalised diagnosis and management of IN and enable accurate genetic counselling. This will allow development of a new clinical care pathway for IN.European Journal of Human Genetics advance online publication, 5 April 2017; doi:10.1038/ejhg.2017.44.

  8. Sputter target

    DOEpatents

    Gates, Willard G.; Hale, Gerald J.

    1980-01-01

    The disclosure relates to an improved sputter target for use in the deposition of hard coatings. An exemplary target is given wherein titanium diboride is brazed to a tantalum backing plate using a gold-palladium-nickel braze alloy.

  9. Metallic coating of microspheres

    SciTech Connect

    Meyer, S.F.

    1980-08-15

    Extremely smooth, uniform metal coatings of micrometer thicknesses on microscopic glass spheres (microspheres) are often needed as targets for inertial confinement fusion (ICF) experiments. The first part of this paper reviews those methods used successfully to provide metal coated microspheres for ICF targets, including magnetron sputtering, electro- and electroless plating, and chemical vapor pyrolysis. The second part of this paper discusses some of the critical aspects of magnetron sputter coating of microspheres, including substrate requirements, the sticking of microspheres during coating (preventing a uniform coating), and the difficulties in growing the desired dense, smooth, uniform microstructure on continuously moving spherical substrates.

  10. FMN-coated fluorescent iron oxide nanoparticles for RCP-mediated targeting and labeling of metabolically active cancer and endothelial cells.

    PubMed

    Jayapaul, Jabadurai; Hodenius, Michael; Arns, Susanne; Lederle, Wiltrud; Lammers, Twan; Comba, Peter; Kiessling, Fabian; Gaetjens, Jessica

    2011-09-01

    Riboflavin is an essential vitamin for cellular metabolism and is highly upregulated in metabolically active cells. Consequently, targeting the riboflavin carrier protein (RCP) may be a promising strategy for labeling cancer and activated endothelial cells. Therefore, Ultrasmall SuperParamagnetic Iron Oxide nanoparticles (USPIO) were adsorptively coated with the endogenous RCP ligand flavin mononucleotide (FMN), which renders them target-specific and fluorescent. The core diameter, surface morphology and surface coverage of the resulting FMN-coated USPIO (FLUSPIO) were evaluated using a variety of physico-chemical characterization techniques (TEM, DLS, MRI and fluorescence spectroscopy). The biocompatibility of FLUSPIO was confirmed using three different cell viability assays (Trypan blue staining, 7-AAD staining and TUNEL). In vitro evaluation of FLUSPIO using MRI and fluorescence microscopy demonstrated high labeling efficiency of cancer cells (PC-3, DU-145, LnCap) and activated endothelial cells (HUVEC). Competition experiments (using MRI and ICP-MS) with a 10- and 100-fold excess of free FMN confirmed RCP-specific uptake of the FLUSPIO by PC-3 cells and HUVEC. Hence, RCP-targeting via FMN may be an elegant way to render nanoparticles fluorescent and to increase the labeling efficacy of cancer and activated endothelial cells. This was shown for FLUSPIO, which due to their high T(2)-relaxivity, are favorably suited for MR cell tracking experiments and cancer detection in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. RGD-conjugated silica-coated gold nanorods on the surface of carbon nanotubes for targeted photoacoustic imaging of gastric cancer.

    PubMed

    Wang, Can; Bao, Chenchen; Liang, Shujing; Fu, Hualin; Wang, Kan; Deng, Min; Liao, Qiande; Cui, Daxiang

    2014-01-01

    Herein, we reported for the first time that RGD-conjugated silica-coated gold nanorods on the surface of multiwalled carbon nanotubes were successfully used for targeted photoacoustic imaging of in vivo gastric cancer cells. A simple strategy was used to attach covalently silica-coated gold nanorods (sGNRs) onto the surface of multiwalled carbon nanotubes (MWNTs) to fabricate a hybrid nanostructure. The cross-linked reaction occurred through the combination of carboxyl groups on the MWNTs and the amino group on the surface of sGNRs modified with a silane coupling agent. RGD peptides were conjugated with the sGNR/MWNT nanostructure; resultant RGD-conjugated sGNR/MWNT probes were investigated for their influences on viability of MGC803 and GES-1 cells. The nude mice models loaded with gastric cancer cells were prepared, the RGD-conjugated sGNR/MWNT probes were injected into gastric cancer-bearing nude mice models via the tail vein, and the nude mice were observed by an optoacoustic imaging system. Results showed that RGD-conjugated sGNR/MWNT probes showed good water solubility and low cellular toxicity, could target in vivo gastric cancer cells, and obtained strong photoacoustic imaging in the nude model. RGD-conjugated sGNR/MWNT probes will own great potential in applications such as targeted photoacoustic imaging and photothermal therapy in the near future.

  12. Theranostic MUC-1 aptamer targeted gold coated superparamagnetic iron oxide nanoparticles for magnetic resonance imaging and photothermal therapy of colon cancer.

    PubMed

    Azhdarzadeh, Morteza; Atyabi, Fatemeh; Saei, Amir Ata; Varnamkhasti, Behrang Shiri; Omidi, Yadollah; Fateh, Mohsen; Ghavami, Mahdi; Shanehsazzadeh, Saeed; Dinarvand, Rassoul

    2016-07-01

    Favorable physiochemical properties and the capability to accommodate targeting moieties make superparamegnetic iron oxide nanoparticles (SPIONs) popular theranostic agents. In this study, we engineered SPIONs for magnetic resonance imaging (MRI) and photothermal therapy of colon cancer cells. SPIONs were synthesized by microemulsion method and were then coated with gold to reduce their cytotoxicity and to confer photothermal capabilities. Subsequently, the NPs were conjugated with thiol modified MUC-1 aptamers. The resulting NPs were spherical, monodisperse and about 19nm in size, as shown by differential light scattering (DLS) and transmission electron microscopy (TEM). UV and X-ray photoelectron spectroscopy (XPS) confirmed the successful gold coating. MTT results showed that Au@SPIONs have insignificant cytotoxicity at the concentration range of 10-100μg/ml (P>0.05) and that NPs covered with protein corona exerted lower cytotoxicity than bare NPs. Furthermore, confocal microscopy confirmed the higher uptake of aptamer-Au@SPIONs in comparison with non-targeted SPIONs. MR imaging revealed that SPIONs produced significant contrast enhancement in vitro and they could be exploited as contrast agents. Finally, cells treated with aptamer-Au@SPIONs exhibited a higher death rate compared to control cells upon exposure to near infrared light (NIR). In conclusion, MUC1-aptamer targeted Au@SPIONs could serve as promising theranostic agents for simultaneous MR imaging and photothermal therapy of cancer cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. RGD-conjugated silica-coated gold nanorods on the surface of carbon nanotubes for targeted photoacoustic imaging of gastric cancer

    NASA Astrophysics Data System (ADS)

    Wang, Can; Bao, Chenchen; Liang, Shujing; Fu, Hualin; Wang, Kan; Deng, Min; Liao, Qiande; Cui, Daxiang

    2014-05-01

    Herein, we reported for the first time that RGD-conjugated silica-coated gold nanorods on the surface of multiwalled carbon nanotubes were successfully used for targeted photoacoustic imaging of in vivo gastric cancer cells. A simple strategy was used to attach covalently silica-coated gold nanorods (sGNRs) onto the surface of multiwalled carbon nanotubes (MWNTs) to fabricate a hybrid nanostructure. The cross-linked reaction occurred through the combination of carboxyl groups on the MWNTs and the amino group on the surface of sGNRs modified with a silane coupling agent. RGD peptides were conjugated with the sGNR/MWNT nanostructure; resultant RGD-conjugated sGNR/MWNT probes were investigated for their influences on viability of MGC803 and GES-1 cells. The nude mice models loaded with gastric cancer cells were prepared, the RGD-conjugated sGNR/MWNT probes were injected into gastric cancer-bearing nude mice models via the tail vein, and the nude mice were observed by an optoacoustic imaging system. Results showed that RGD-conjugated sGNR/MWNT probes showed good water solubility and low cellular toxicity, could target in vivo gastric cancer cells, and obtained strong photoacoustic imaging in the nude model. RGD-conjugated sGNR/MWNT probes will own great potential in applications such as targeted photoacoustic imaging and photothermal therapy in the near future.

  14. Utilization of peptide carrier system to improve intestinal absorption: targeting prolidase as a prodrug-converting enzyme

    NASA Technical Reports Server (NTRS)

    Bai, J. P.; Hu, M.; Subramanian, P.; Mosberg, H. I.; Amidon, G. L.

    1992-01-01

    The feasibility of targeting prolidase as a peptide prodrug-converting enzyme has been examined. The enzymatic hydrolysis by prolidase of substrates for the peptide transporter L-alpha-methyldopa-pro and several dipeptide analogues without an N-terminal alpha-amino group (phenylpropionylproline, phenylacetylproline, N-benzoylproline, and N-acetylproline) was investigated. The Michaelis-Menten parameters Km and Vmax for L-alpha-methyldopa-pro are 0.09 +/- 0.02 mM and 3.98 +/- 0.25 mumol/min/mg protein, respectively. However, no hydrolysis of the dipeptide analogues without an N-terminal alpha-amino group is observed, suggesting that an N-terminal alpha-amino group is required for prolidase activity. These results demonstrate that prolidase may serve as a prodrug-converting enzyme for the dipeptide-type prodrugs, utilizing the peptide carrier for transport of prodrugs into the mucosal cells and prolidase, a cytosolic enzyme, to release the drug. However, a free alpha-amino group appears to be necessary for prolidase hydrolysis.

  15. The Nociceptin Opioid Receptor (NOP) as a Therapeutic Target: Progress in Translation from Preclinical Research to Clinical Utility

    PubMed Central

    Zaveri, Nurulain T.

    2016-01-01

    In the two decades since the discovery of the nociceptin opioid receptor (NOP) and its ligand, nociceptin/orphaninFQ (N/OFQ), steady progress has been achieved in understanding the pharmacology of this fourth opioid receptor/peptide system, aided by genetic and pharmacologic approaches. This research spawned an explosion of small-molecule NOP receptor ligands from discovery programs in major pharmaceutical companies. NOP agonists have been investigated for their efficacy in preclinical models of anxiety, cough, substance abuse, pain (spinal and peripheral) and urinary incontinence, whereas NOP antagonists have been investigated for treatment of pain, depression and motor symptoms in Parkinson’s disease. Translation of preclinical findings into the clinic is guided by PET and receptor occupancy studies, particularly for NOP antagonists. Recent progress in preclinical NOP research suggests that NOP agonists may have clinical utility for pain treatment and substance abuse pharmacotherapy. This review discusses the progress towards validating the NOP-N/OFQ system as a therapeutic target. PMID:26878436

  16. Comparative assessment of diverse strategies for malaria vector population control based on measured rates at which mosquitoes utilize targeted resource subsets.

    PubMed

    Killeen, Gerry F; Kiware, Samson S; Seyoum, Aklilu; Gimnig, John E; Corliss, George F; Stevenson, Jennifer; Drakeley, Christopher J; Chitnis, Nakul

    2014-08-28

    Eliminating malaria requires vector control interventions that dramatically reduce adult mosquito population densities and survival rates. Indoor applications of insecticidal nets and sprays are effective against an important minority of mosquito species that rely heavily upon human blood and habitations for survival. However, complementary approaches are needed to tackle a broader diversity of less human-specialized vectors by killing them at other resource targets. Impacts of strategies that target insecticides to humans or animals can be rationalized in terms of biological coverage of blood resources, quantified as proportional coverage of all blood resources mosquito vectors utilize. Here, this concept is adapted to enable impact prediction for diverse vector control strategies based on measurements of utilization rates for any definable, targetable resource subset, even if that overall resource is not quantifiable. The usefulness of this approach is illustrated by deriving utilization rate estimates for various blood, resting site, and sugar resource subsets from existing entomological survey data. Reported impacts of insecticidal nets upon human-feeding vectors, and insecticide-treated livestock upon animal-feeding vectors, are approximately consistent with model predictions based on measured utilization rates for those human and animal blood resource subsets. Utilization rates for artificial sugar baits compare well with blood resources, and are consistent with observed impact when insecticide is added. While existing data was used to indirectly measure utilization rates for a variety of resting site subsets, by comparison with measured rates of blood resource utilization in the same settings, current techniques for capturing resting mosquitoes underestimate this quantity, and reliance upon complex models with numerous input parameters may limit the applicability of this approach. While blood and sugar consumption can be readily quantified using existing

  17. Formulation and optimization of coated PLGA - Zidovudine nanoparticles using factorial design and in vitro in vivo evaluations to determine brain targeting efficiency.

    PubMed

    Peter Christoper, G V; Vijaya Raghavan, C; Siddharth, K; Siva Selva Kumar, M; Hari Prasad, R

    2014-04-01

    In the current study zidovudine loaded PLGA nanoparticles were prepared, coated and further investigated for its effectiveness in brain targeting. IR and DSC studies were performed to determine the interaction between excipients used and to find out the nature of drug in the formulation. Formulations were prepared by adopting 2(3) factorial designs to evaluate the effects of process and formulation variables. The prepared formulations were subjected for in vitro and in vivo evaluations. In vitro evaluations showed particle size below 100 nm, entrapment efficiency of formulations ranges of 28-57%, process yield of 60-76% was achieved and drug release for the formulations were in the range of 50-85%. The drug release from the formulations was found to follow Higuchi release pattern, n-value obtained after Korsemeyer plot was in the range of 0.56-0.78. In vivo evaluations were performed in mice after intraperitoneal administration of zidovudine drug solution, uncoated and coated formulation. Formulation when coated with Tween 80 achieved a higher concentration in the brain than that of the drug in solution and of the uncoated formulation. Stability studies indicated that there was no degradation of the drug in the formulation after 90 days of preparation when stored in refrigerated condition.

  18. [Synthesis and bioactivity of the folate receptor targeted gamma-cyclodextrin-folate inclusion-coated CdSe/ZnS quantum dots].

    PubMed

    Zhao, Mei-Xia; Li, Yang; Wang, Chao-Jie

    2013-04-01

    The gamma-cyclodextrin-folate (gamma-CD/FA) inclusion-coated CdSe/ZnS quantum dots (QDs) with folate-receptor (FR) targeted were synthesized by simple and convenient sonochemical method. The products were studied using Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), utraviolet-visible spectrometry (UV-vis), fluorescence spectrum and transmission electron micrographs (TEM). The results showed that the gamma-CD/FA-coated CdSe/ZnS QDs not only have good monodispersity and smaller size, but also have good optical performance, such as higher quantum yield (QY) and a long fluorescence lifetime. The cytotoxicity experiments showed that the gamma-CD/FA-coated CdSe/ZnS QDs have lower cytotoxicity and could more effectively enter cancer cells with FR over-expression. The QDs with 4-5 nm in diameter were relatively easy to enter the cell and to be removed through kidneys, so it is more suitable for biomedical applications for bioprobes and bioimaging.

  19. Formulation and optimization of coated PLGA – Zidovudine nanoparticles using factorial design and in vitro in vivo evaluations to determine brain targeting efficiency

    PubMed Central

    Peter Christoper, G.V.; Vijaya Raghavan, C.; Siddharth, K.; Siva Selva Kumar, M.; Hari Prasad, R.

    2013-01-01

    In the current study zidovudine loaded PLGA nanoparticles were prepared, coated and further investigated for its effectiveness in brain targeting. IR and DSC studies were performed to determine the interaction between excipients used and to find out the nature of drug in the formulation. Formulations were prepared by adopting 23 factorial designs to evaluate the effects of process and formulation variables. The prepared formulations were subjected for in vitro and in vivo evaluations. In vitro evaluations showed particle size below 100 nm, entrapment efficiency of formulations ranges of 28–57%, process yield of 60–76% was achieved and drug release for the formulations were in the range of 50–85%. The drug release from the formulations was found to follow Higuchi release pattern, n–value obtained after Korsemeyer plot was in the range of 0.56–0.78. In vivo evaluations were performed in mice after intraperitoneal administration of zidovudine drug solution, uncoated and coated formulation. Formulation when coated with Tween 80 achieved a higher concentration in the brain than that of the drug in solution and of the uncoated formulation. Stability studies indicated that there was no degradation of the drug in the formulation after 90 days of preparation when stored in refrigerated condition. PMID:24648825

  20. Internalization of IgG-Coated Targets Results in Activation and Secretion of Soluble CD40 Ligand and RANTES by Human Platelets ▿

    PubMed Central

    Antczak, Adam J.; Vieth, Joshua A.; Singh, Navinderjit; Worth, Randall G.

    2011-01-01

    Platelets are crucial elements for maintenance of hemostasis. Other functions attributable to platelets are now being appreciated, such as their role in inflammatory reactions and host defense. Platelets have been reported to bind immunological stimuli like IgG complexes, and for nearly 50 years it has been speculated that platelets may participate in immunological reactions. Platelets have been reported to bind and internalize various substances, similar to other leukocytes, such as macrophages and dendritic cells. In the present study, we tested the hypothesis that human platelets can bind and internalize IgG-coated particles, similar to leukocytes. To this end, we observed that interaction with IgG-coated beads resulted in platelet activation (as measured by CD62P expression), internalization of targets, and significant soluble CD40 ligand (sCD40L) and RANTES (regulated upon activation, normal T cell expresses and secreted) secretion. Blocking FcγRIIA with monoclonal antibody (MAb) IV.3 or inhibiting actin remodeling with cytochalasin D inhibited platelet activation, internalization, and cytokine production. These data suggest that platelets are capable of mediating internalization of IgG-coated particles, resulting in platelet activation and release of both sCD40L and RANTES. PMID:21177916

  1. Coated minispheres of salmon calcitonin target rat intestinal regions to achieve systemic bioavailability: Comparison between intestinal instillation and oral gavage.

    PubMed

    Aguirre, Tanira A S; Aversa, Vincenzo; Rosa, Mónica; Guterres, Sílvia S; Pohlmann, Adriana R; Coulter, Ivan; Brayden, David J

    2016-09-28

    Achieving oral peptide delivery is an elusive challenge. Emulsion-based minispheres of salmon calcitonin (sCT) were synthesized using single multiple pill (SmPill®) technology incorporating the permeation enhancers (PEs): sodium taurodeoxycholate (NaTDC), sodium caprate (C10), or coco-glucoside (CG), or the pH acidifier, citric acid (CA). Minispheres were coated with an outer layer of Eudragit® L30 D-55 (designed for jejunal release) or Surelease®/Pectin (designed for colonic release). The process was mild and in vitro biological activity of sCT was retained upon release from minispheres stored up to 4months. In vitro release profiles suggested that sCT was released from minispheres by diffusion through coatings due to swelling of gelatin and the polymeric matrix upon contact with PBS at pH6.8. X-ray analysis confirmed that coated minispheres dissolved at the intended intestinal region of rats following oral gavage. Uncoated minispheres at a dose of ~2000I.U.sCT/kg were administered to rats by intra-jejunal (i.j.) or intra-colonic (i.c.) instillation and caused hypocalcaemia. Notable sCT absolute bioavailability (F) values were: 5.5% from minispheres containing NaTDC (i.j), 17.3% with CG (i.c.) and 18.2% with C10 (i.c.). Coated minispheres administered by oral gavage at threefold higher doses also induced hypocalcaemia. A highly competitive F value of 2.7% was obtained for orally-administered sCT-minispheres containing CG (45μmol/kg) and coated with Eudragit®. In conclusion, the SmPill® technology is a potential dosage form for several peptides when formulated with PEs and coated for regional delivery. PK data from instillations over-estimates oral bioavailability and poorly predicts rank ordering of formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Difference in clinical target lesion revascularization between a silicon carbide-coated and an uncoated thin strut bare-metal stent: the PRO-Vision study.

    PubMed

    Haine, Steven E; Cornez, Barbara M; Jacobs, Jimmy M; Miljoen, Hielko P; Vandendriessche, Tom R; Claeys, Marc J; Bosmans, Johan M; Vrints, Christiaan J

    2013-09-01

    Bare-metal stents trigger a foreign body reaction, resulting in neointima formation and restenosis. Silicon carbide (SiC) coating shields the metal from circulating blood and vessel wall, both potential sources of neointima smooth muscle cells. We investigated whether SiC-coated stents (PRO-Kinetic) have lower clinical target lesion revascularization (TLR) rates than do uncoated bare-metal stents (Vision). Stents were implanted in 2731 patients during 2 consecutive 18-month periods. Clinical TLR was evaluated at 1 year. In the PRO-Kinetic group, TLR was significantly higher (9.0% vs 5.6%; unadjusted odds ratio, 1.61; 95% confidence interval [CI], 1.24-2.08; P < 0.001) compared with the Vision group. After adjustment for postintervention minimal luminal diameter (adjusted odds ratio [AOR], 0.56; 95% CI, 0.42-0.73), total implanted stent length (AOR, 1.01; 95% CI, 1.00-1.02), non-ST-segment elevation myocardial infarction or unstable angina at initial presentation (AOR, 1.89; 95% CI, 1.41-2.54), and triple vessel stenting (AOR, 2.68; 95% CI, 1.02-7.05), the use of PRO-Kinetic stents remained an independent predictor for revascularization (AOR, 1.57; 95% CI, 1.18-2.10; P = 0.002). Because strut thickness is lower in 2.0- to 3.0-mm PRO-Kinetic stents, a subgroup analysis (n = 2382 lesions) was performed. Even in this subgroup, PRO-Kinetic implantation proved an independent predictor of TLR (AOR, 1.62; 95% CI, 1.17-2.23; P = 0.003). In contrast to theoretical expectations, the SiC-coated PRO-Kinetic stent was associated with greater target lesion revascularization rates at 1 year compared with the uncoated Vision stent. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  3. Hyaluronan Polymer Length, Grafting Density, and Surface Poly(ethylene glycol) Coating Influence in Vivo Circulation and Tumor Targeting of Hyaluronan-Grafted Liposomes

    PubMed Central

    2015-01-01

    Hyaluronan-grafted liposomes (HA-liposomes) preferentially target CD44-overexpressing tumor cells in vitro via receptor-mediated endocytosis. We investigated the pharmacokinetics and biodistribution of HA-liposomes with various sizes of HA (MW 5–8, 50–60, and 175–350 kDa) in mice. Incorporation of negatively charged HA on the liposome surface compromised its blood circulation time, which led to decreased tumor accumulation in CD44+ human breast cancer MDA-MB-231 xenografts compared to PEGylated liposomes (PEG-5000). Clearance of HA-liposomes was HA polymer length-dependent; high MW (175–350 kDa, highest ligand binding affinity) HA-liposomes displayed faster clearance compared to low MW (5–8, 50–60 kDa) HA-liposomes or PEGylated liposomes. Surface HA ligand density can also affect clearance of HA-liposomes. Thus, HA is not an effective stealth coating material. When dual coating of PEG and HA was used, the PEG-HA-liposomes displayed similar blood circulation time and tumor accumulation to that of the PEGylated liposomes; however, the PEG-HA-liposomes displayed better cellular internalization capability in vivo. Tumor histology showed that PEG-HA-liposomes had a more direct association with CD44+ cancer cells, while PEGylated liposomes located predominantly in the tumor periphery, with less association with CD44+ cells. Flow cytometry analysis of ex vivo tumor cells showed that PEG-HA-liposomes had significantly higher tumor cell internalization compared to PEGylated liposomes. This study demonstrates that a long blood circulation time is critical for active tumor targeting. Furthermore, the use of the tumor-targeting ligand HA does not increase total tumor accumulation of actively targeted liposomes in solid tumors; however, it can enhance intracellular delivery. PMID:24806526

  4. Targeted oral delivery of BmpB vaccine using porous PLGA microparticles coated with M cell homing peptide-coupled chitosan.

    PubMed

    Jiang, Tao; Singh, Bijay; Li, Hui-Shan; Kim, You-Kyoung; Kang, Sang-Kee; Nah, Jae-Woon; Choi, Yun-Jaie; Cho, Chong-Su

    2014-02-01

    M cells, the key players of the mucosal immunity induction, are one of the intestinal barriers for the efficient delivery of vaccines to mucosal immune tissues. To overcome the barrier, we have developed an efficient oral vaccine carrier that constitutes poly (lactic-co-glycolic acid) (PLGA) microparticle coated with M cell targeting peptide. In this study, a membrane protein B of Brachyspira hyodysenteriae (BmpB) as a model vaccine against swine dysentery was loaded into porous PLGA microparticles (MPs). The PLGA MPs were further coated with the water-soluble chitosan (WSC) conjugated with M cell homing peptide (CKS9) to prepare BmpB-CKS9-WSC-PLGA MPs. Oral immunization of BmpB vaccine with CKS9-WSC-PLGA MPs in mice showed elevated secretory IgA responses in the mucosal tissues and systemic IgG antibody responses, providing a complete immune response. Specifically, the immunization with these MPs demonstrated to induce both Th1- and Th2-type responses based on elevated IgG1 and IgG2a titers. The elevated immune responses were attributed to the enhanced M cell targeting and transcytosis ability of CKS9-WSC-PLGA MPs to Peyer's patch regions. The high binding affinity of CKS9-WSC-PLGA MPs with the M cells to enter into the Peyer's patch regions of mouse small intestine was investigated by closed ileal loop assay and it was further confirmed by confocal laser scanning microscopy. These results suggest that the M cell targeting approach used in this study is a promising tool for targeted oral vaccine delivery.

  5. Thermal barrier coating system

    NASA Technical Reports Server (NTRS)

    Stecura, S.; Leibert, C. H. (Inventor)

    1977-01-01

    A coating system which contains a bond coating and a thermal barrier coating is applied to metal surfaces such as turbine blades and provides both low thermal conductivity and improved adherence when exposed to high temperature gases or liquids. The bond coating contains NiCrAlY and the thermal barrier coating contains a reflective oxide. The reflective oxides ZrO2-Y2O3 and ZrO2-MgO have demonstrated significant utility in high temperature turbine applications.

  6. Diamond Coatings

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Advances in materials technology have demonstrated that it is possible to get the advantages of diamond in a number of applications without the cost penalty, by coating and chemically bonding an inexpensive substrate with a thin film of diamond-like carbon (DLC). Diamond films offer tremendous technical and economic potential in such advances as chemically inert protective coatings; machine tools and parts capable of resisting wear 10 times longer; ball bearings and metal cutting tools; a broad variety of optical instruments and systems; and consumer products. Among the American companies engaged in DLC commercialization is Diamonex, Inc., a diamond coating spinoff of Air Products and Chemicals, Inc. Along with its own proprietary technology for both polycrystalline diamond and DLC coatings, Diamonex is using, under an exclusive license, NASA technology for depositing DLC on a substrate. Diamonex is developing, and offering commercially, under the trade name Diamond Aegis, a line of polycrystalline diamond-coated products that can be custom tailored for optical, electronic and engineering applications. Diamonex's initial focus is on optical products and the first commercial product is expected in late 1990. Other target applications include electronic heat sink substrates, x-ray lithography masks, metal cutting tools and bearings.

  7. A facile approach to functionalizing cell membrane-coated nanoparticles with neurotoxin-derived peptide for brain-targeted drug delivery.

    PubMed

    Chai, Zhilan; Hu, Xuefeng; Wei, Xiaoli; Zhan, Changyou; Lu, Linwei; Jiang, Kuan; Su, Bingxia; Ruan, Huitong; Ran, Danni; Fang, Ronnie H; Zhang, Liangfang; Lu, Weiyue

    2017-08-24

    The blood brain barrier separates the circulating blood from the extracellular fluid in the central nervous system and thus presents an essential obstacle to brain transport of therapeutics. Herein, we report on an effective brain-targeted drug delivery system that combines a robust red blood cell membrane-coated nanoparticle (RBCNP) with a unique neurotoxin-derived targeting moiety. The RBCNPs retain the complex biological functions of natural cell membranes while exhibiting physicochemical properties that are suitable for effective drug delivery. CDX peptide is derived from candoxin and shows high binding affinity with nicotinic acetylcholine receptors (nAChRs) expressed on the surface of brain endothelial cells. Through a facile yet robust approach, we successfully incorporate (D)CDX peptides onto the surface of RBCNPs without compromising the peptide's brain targeting ability. The resulting (D)CDX-RBCNPs show promising brain targeting efficiency both in vitro and in vivo. Using a glioma mouse model, we demonstrate that doxorubicin-loaded (D)CDX-RBCNPs have superior therapeutic efficacy and markedly reduced toxicity as compared to the nontargeted drug formulations. While RBCNPs are used as a model system to evaluate the surface modification approach, the reported method can be readily generalized to various types of cell membrane-derived nanocarriers for broad medical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Bifunctional Succinylated ε-Polylysine Coated Mesoporous Silica Nanoparticles for pH-Responsive and Intracellular Drug Delivery Targeting the Colon.

    PubMed

    Nguyen, Chau; Webb, Richard; Lambert, Lynette; Strounina, Ekaterina; Lee, Edward; Parat, Marie-Odile; McGuckin, Michael; Popat, Amirali; Cabot, Peter; Ross, Benjamin P

    2017-03-02

    Conventional oral drug formulations for colonic diseases require the administration of high doses of drug to achieve effective drug concentrations at the target site. However, this exposes patients to serious systemic toxicity in order to achieve efficacy. To overcome this problem, an oral drug delivery system was developed by loading a large amount (ca. 34% w/w) of prednisolone into 3-aminopropyl-functionalized mesoporous silica nanoparticles (MCM-NH2), and targeting prednisolone release to the colon by coating the nanoparticle with succinylated ε-polylysine (SPL). We demonstrate for the first time the pH-responsive ability of SPL as a "nanogate" to selectively release prednisolone in the pH conditions of the colon (pH 5.5 to 7.4) but not in the more acidic conditions of the stomach (pH 1.9) or small intestine (pH 5.0). In addition to targeting drug delivery to the colon, we explored whether the nanoparticles could deliver cargo intracellularly to immune cells (RAW 264.7 macrophages) and intestinal epithelial cells (LS 174T and Caco-2 adenocarcinoma cell lines). To trace uptake, MCM-NH2 were loaded with a cell membrane-impermeable dye, sulforhodamine B. The SPL-coated nanoparticles were able to deliver the dye intracellularly to RAW264.7 macrophages and the intestinal epithelial cancer cells, which offers a highly promising and novel drug delivery system for diseases of the colon such as inflammatory bowel disease and colorectal cancer.

  9. Advanced process control and novel test methods for PVD silicon and elastomeric silicone coatings utilized on ion implant disks, heatsinks and selected platens

    NASA Astrophysics Data System (ADS)

    Springer, J.; Allen, B.; Wriggins, W.; Kuzbyt, R.; Sinclair, R.

    2012-11-01

    Coatings play multiple key roles in the proper functioning of mature and current ion implanters. Batch and serial implanters require strategic control of elemental and particulate contamination which often includes scrutiny of the silicon surface coatings encountering direct beam contact. Elastomeric Silicone Coatings must accommodate wafer loading and unloading as well as direct backside contact during implant plus must maintain rigid elemental and particulate specifications. The semiconductor industry has had a significant and continuous effort to obtain ultra-pure silicon coatings with sustained process performance and long life. Low particles and reduced elemental levels for silicon coatings are a major requirement for process engineers, OEM manufacturers, and second source suppliers. Relevant data will be presented. Some emphasis and detail will be placed on the structure and characteristics of a relatively new PVD Silicon Coating process that is very dense and homogeneous. Wear rate under typical ion beam test conditions will be discussed. The PVD Silicon Coating that will be presented here is used on disk shields, wafer handling fingers/fences, exclusion zones of heat sinks, beam dumps and other beamline components. Older, legacy implanters can now provide extended process capability using this new generation PVD silicon - even on implanter systems that were shipped long before the advent of silicon coating for contamination control. Low particles and reduced elemental levels are critical performance criteria for the silicone elastomers used on disk heatsinks and serial implanter platens. Novel evaluation techniques and custom engineered tools are used to investigate the surface interaction characteristics of multiple Elastomeric Silicone Coatings currently in use by the industry - specifically, friction and perpendicular stiction. These parameters are presented as methods to investigate the critical wafer load and unload function. Unique tools and test

  10. Advanced process control and novel test methods for PVD silicon and elastomeric silicone coatings utilized on ion implant disks, heatsinks and selected platens

    SciTech Connect

    Springer, J.; Allen, B.; Wriggins, W.; Kuzbyt, R.; Sinclair, R.

    2012-11-06

    Coatings play multiple key roles in the proper functioning of mature and current ion implanters. Batch and serial implanters require strategic control of elemental and particulate contamination which often includes scrutiny of the silicon surface coatings encountering direct beam contact. Elastomeric Silicone Coatings must accommodate wafer loading and unloading as well as direct backside contact during implant plus must maintain rigid elemental and particulate specifications. The semiconductor industry has had a significant and continuous effort to obtain ultra-pure silicon coatings with sustained process performance and long life. Low particles and reduced elemental levels for silicon coatings are a major requirement for process engineers, OEM manufacturers, and second source suppliers. Relevant data will be presented. Some emphasis and detail will be placed on the structure and characteristics of a relatively new PVD Silicon Coating process that is very dense and homogeneous. Wear rate under typical ion beam test conditions will be discussed. The PVD Silicon Coating that will be presented here is used on disk shields, wafer handling fingers/fences, exclusion zones of heat sinks, beam dumps and other beamline components. Older, legacy implanters can now provide extended process capability using this new generation PVD silicon - even on implanter systems that were shipped long before the advent of silicon coating for contamination control. Low particles and reduced elemental levels are critical performance criteria for the silicone elastomers used on disk heatsinks and serial implanter platens. Novel evaluation techniques and custom engineered tools are used to investigate the surface interaction characteristics of multiple Elastomeric Silicone Coatings currently in use by the industry - specifically, friction and perpendicular stiction. These parameters are presented as methods to investigate the critical wafer load and unload function. Unique tools and test

  11. Trypsin and MALDI matrix pre-coated targets simplify sample preparation for mapping proteomic distributions within biological tissues by imaging mass spectrometry.

    PubMed

    Zubair, Faizan; Laibinis, Paul E; Swisher, William G; Yang, Junhai; Spraggins, Jeffrey M; Norris, Jeremy L; Caprioli, Richard M

    2016-12-01

    Prefabricated surfaces containing α-cyano-4-hydroxycinnamic acid and trypsin have been developed to facilitate enzymatic digestion of endogenous tissue proteins prior to matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS). Tissue sections are placed onto slides that were previously coated with α-cyano-4-hydroxycinnamic acid and trypsin. After incubation to promote enzymatic digestion, the tissue is analyzed by MALDI IMS to determine the spatial distribution of the tryptic fragments. The peptides detected in the MALDI IMS dataset were identified by Liquid chromatography-tandem mass spectrometry/mass spectrometry. Protein identification was further confirmed by correlating the localization of unique tryptic fragments originating from common parent proteins. Using this procedure, proteins with molecular weights as large as 300 kDa were identified and their distributions were imaged in sections of rat brain. In particular, large proteins such as myristoylated alanine-rich C-kinase substrate (29.8 kDa) and spectrin alpha chain, non-erythrocytic 1 (284 kDa) were detected that are not observed without trypsin. The pre-coated targets simplify workflow and increase sample throughput by decreasing the sample preparation time. Further, the approach allows imaging at higher spatial resolution compared with robotic spotters that apply one drop at a time. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Syk activation is a leukotriene B4-regulated event involved in macrophage phagocytosis of IgG-coated targets but not apoptotic cells.

    PubMed

    Canetti, Claudio; Hu, Bin; Curtis, Jeffrey L; Peters-Golden, Marc

    2003-09-01

    Macrophages are called upon to ingest both IgG-coated targets and apoptotic cells. Important roles for tyrosine kinase Syk and leukotriene B4 (LTB4) are recognized in FcgammaR-mediated phagocytosis. Here we evaluated the roles of Syk and LTB4 in macrophage phagocytosis of apoptotic thymocytes versus IgG-coated erythrocytes. Macrophage ingestion of apoptotic thymocytes was not influenced by exogenous or endogenous LTB4 nor associated with Syk activation (phosphorylation). By contrast, LTB4 dose-dependently amplified FcgammaR-mediated phagocytosis as well as Syk activation. Furthermore, a role for endogenous LTB4 in Syk activation during FcgammaR-mediated phagocytosis was demonstrated using pharmacologic and genetic abrogation of 5-lipoxygenase. LTB4 was unique among 5-lipoxygenase products in this regard, since LTD4 and 5-hydroxyeicosatetraenoic acid (HETE) were unable to amplify Syk activation in response to FcgammaR engagement. Ca2+ chelation studies revealed that FcgammaR-mediated Syk activation as well as LTB4 amplification thereof was Ca2+ regulated. These 2 parallel phagocytic processes therefore exhibit initial divergence in signal transduction events, with Syk activation being an LTB4-regulated event in FcgammaR-mediated but not apoptotic cell ingestion. As LTB4 is an important proinflammatory product of macrophages, we speculate that this divergence evolved to permit FcgammaR-mediated phagocytosis to proceed in an inflammatory milieu, while apoptotic cell clearance is noninflammatory.

  13. ISS Efforts to Fully Utilize its Target Acquisition Capability Serves as an Analog for Future Laser Pointing Communications Systems

    NASA Technical Reports Server (NTRS)

    Jackson, Dan

    2017-01-01

    The ISS is an outstanding platform for developing, testing and refining laser communications systems for future exploration. A recent ISS project which improved ISS communications satellite acquisition performance proves the platform’s utility as a laser communications systems testbed.

  14. Preparation of surface multiple-coated polylactide acid drug-loaded nanoparticles for intranasal delivery and evaluation on its brain-targeting efficiency.

    PubMed

    Bian, Junjie; Yuan, Zhixiang; Chen, Xiaoliang; Gao, Yuan; Xu, Chaoqun; Shi, Jianyou

    2016-01-01

    To prepare a mixture of multiple-coated aniracetam nasal polylactic-acid nanoparticles (M-C-PLA-NP) and evaluate its stability preliminarily in vitro and its brain-targeting efficiency in vivo. The solvent diffusion-evaporation combined with magnetic stirring method has been chosen for the entrapment of aniracetam. The M-C-PLA-NP was characterized with respect to its morphology, particle size, size distribution and aniracetam entrapment efficiency. The in vivo distribution was studied in male SD rats after an intranasal administration. In vitro release of M-C-PLA-NP showed two components with an initial rapid release due to the surface-associated drug and followed by a slower exponential release of aniracetam, which was dissolved in the core. The AUC0 → 30 min of M-C-PLA-NP in brain tissues resulted in a 5.19-fold increase compared with aniracetam solution. The ratios of AUC in brain to that in other tissues obtained after nasal application of M-C-PLA-NP were significantly higher than those of aniracetam solution. Therefore, it can be concluded that M-C-PLA-NP demonstrated its potential on increasing the brain-targeting efficiency of drugs and will be used as novel brain-targeting agent for nasal drug delivery.

  15. CD163-Macrophages Are Involved in Rhabdomyolysis-Induced Kidney Injury and May Be Detected by MRI with Targeted Gold-Coated Iron Oxide Nanoparticles

    PubMed Central

    Rubio-Navarro, Alfonso; Carril, Mónica; Padro, Daniel; Guerrero-Hue, Melanie; Tarín, Carlos; Samaniego, Rafael; Cannata, Pablo; Cano, Ainhoa; Villalobos, Juan Manuel Amaro; Sevillano, Ángel Manuel; Yuste, Claudia; Gutiérrez, Eduardo; Praga, Manuel; Egido, Jesús; Moreno, Juan Antonio

    2016-01-01

    Macrophages play an important role in rhabdomyolysis-acute kidney injury (AKI), although the molecular mechanisms involved in macrophage differentiation are poorly understood. We analyzed the expression and regulation of CD163, a membrane receptor mainly expressed by anti-inflammatory M2 macrophages, in rhabdomyolysis-AKI and developed targeted probes for its specific detection in vivo by MRI. Intramuscular injection of glycerol in mice promoted an early inflammatory response, with elevated proportion of M1 macrophages, and partial differentiation towards a M2 phenotype in later stages, where increased CD163 expression was observed. Immunohistological studies confirmed the presence of CD163-macrophages in human rhabdomyolysis-AKI. In cultured macrophages, myoglobin upregulated CD163 expression via HO-1/IL-10 axis. Moreover, we developed gold-coated iron oxide nanoparticles vectorized with an anti-CD163 antibody that specifically targeted CD163 in kidneys from glycerol-injected mice, as determined by MRI studies, and confirmed by electron microscopy and immunological analysis. Our findings are the first to demonstrate that CD163 is present in both human and experimental rhabdomyolysis-induced AKI, suggesting an important role of this molecule in this pathological condition. Therefore, the use of probes targeting CD163-macrophages by MRI may provide important information about the cellular composition of renal lesion in rhabdomyolysis. PMID:27162559

  16. CD163-Macrophages Are Involved in Rhabdomyolysis-Induced Kidney Injury and May Be Detected by MRI with Targeted Gold-Coated Iron Oxide Nanoparticles.

    PubMed

    Rubio-Navarro, Alfonso; Carril, Mónica; Padro, Daniel; Guerrero-Hue, Melanie; Tarín, Carlos; Samaniego, Rafael; Cannata, Pablo; Cano, Ainhoa; Villalobos, Juan Manuel Amaro; Sevillano, Ángel Manuel; Yuste, Claudia; Gutiérrez, Eduardo; Praga, Manuel; Egido, Jesús; Moreno, Juan Antonio

    2016-01-01

    Macrophages play an important role in rhabdomyolysis-acute kidney injury (AKI), although the molecular mechanisms involved in macrophage differentiation are poorly understood. We analyzed the expression and regulation of CD163, a membrane receptor mainly expressed by anti-inflammatory M2 macrophages, in rhabdomyolysis-AKI and developed targeted probes for its specific detection in vivo by MRI. Intramuscular injection of glycerol in mice promoted an early inflammatory response, with elevated proportion of M1 macrophages, and partial differentiation towards a M2 phenotype in later stages, where increased CD163 expression was observed. Immunohistological studies confirmed the presence of CD163-macrophages in human rhabdomyolysis-AKI. In cultured macrophages, myoglobin upregulated CD163 expression via HO-1/IL-10 axis. Moreover, we developed gold-coated iron oxide nanoparticles vectorized with an anti-CD163 antibody that specifically targeted CD163 in kidneys from glycerol-injected mice, as determined by MRI studies, and confirmed by electron microscopy and immunological analysis. Our findings are the first to demonstrate that CD163 is present in both human and experimental rhabdomyolysis-induced AKI, suggesting an important role of this molecule in this pathological condition. Therefore, the use of probes targeting CD163-macrophages by MRI may provide important information about the cellular composition of renal lesion in rhabdomyolysis.

  17. Direct Solvent-Derived Polymer-Coated Nitrogen-Doped Carbon Nanodots with High Water Solubility for Targeted Fluorescence Imaging of Glioma.

    PubMed

    Wang, Yi; Meng, Ying; Wang, Shanshan; Li, Chengyi; Shi, Wei; Chen, Jian; Wang, Jianxin; Huang, Rongqin

    2015-08-05

    Cancer imaging requires biocompatible and bright contrast-agents with selective and high accumulation in the tumor region but low uptake in normal tissues. Herein, 1-methyl-2-pyrrolidinone (NMP)-derived polymer-coated nitrogen-doped carbon nanodots (pN-CNDs) with a particle size in the range of 5-15 nm are prepared by a facile direct solvothermal reaction. The as-prepared pN-CNDs exhibit stable and adjustable fluorescence and excellent water solubility. Results of a cell viability test (CCK-8) and histology analysis both demonstrate that the pN-CNDs have no obvious cytotoxicity. Most importantly, the pN-CNDs can expediently enter glioma cells in vitro and also mediate glioma fluorescence imaging in vivo with good contrast via elevated passive targeting. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Polyvalent Folate-Dendrimer-Coated Iron Oxide Theranostic Nanoparticles for Simultaneous Magnetic Resonance Imaging and Precise Cancer Cell Targeting.

    PubMed

    Luong, Duy; Sau, Samaresh; Kesharwani, Prashant; Iyer, Arun K

    2017-04-10

    The low therapeutic index of conventional chemotherapy and poor prognosis of patients diagnosed with metastatic cancers are prompting clinicians to adopt newer strategies to simultaneously detect cancer lesions at an early stage and to precisely deliver anticancer drugs to tumor sites. In this study, we employed a novel strategy to engineer a polyvalent theranostic nanocarrier consisting of superparamagnetic iron oxide nanoparticle core (SPIONs) decorated with folic acid-polyamidoamine dendrimers surface (FA-PAMAM). In addition, a highly potent hydrophobic anticancer agent 3,4-difluorobenzylidene-curcumin (CDF) was coloaded in the FA-PAMAM dendrimer to increase its solubility and assess its therapeutic potentials. The resulting targeted nanoparticles (SPIONs@FA-PAMAM-CDF) exhibited high MR contrast. When tested on folate receptor overexpressing ovarian (SKOV3) and cervical (HeLa) cancer cells, the CDF loaded targeted nanoformulations showed higher accumulation with a better anticancer activity as compared to the nontargeted counterparts, possibly due to multivalent folate receptor binding interaction with cells overexpressing the target. The results were corroborated by observation of a larger population of cells undergoing apoptosis due to upregulation of tumor suppressor phosphatase and tensis homologue (PTEN), caspase 3, and inhibition of NF-κB in groups treated with the targeted formulations, which further confirmed the ability of the multivalent theranostic nanoparticles for simultaneous imaging and therapy of cancers.

  19. Enhancing biodistribution of therapeutic enzymes in vivo by modulating surface coating and concentration of ICAM-1-targeted nanocarriers.

    PubMed

    Hsu, Janet; Bhowmick, Tridib; Burks, Scott R; Kao, Joseph P Y; Muro, Silvia

    2014-02-01

    Coupling therapeutic proteins to targeted nanocarriers can enhance their biodistribution. This is the case for enzyme replacement therapies where intravenously injected enzymes must avoid prolonged blood exposure while reaching body organs. We have shown enhanced tissue targeting of various lysosomal enzymes by coupling to nanocarriers targeted to intercellular adhesion molecule-1 (ICAM-1). Here, we varied design parameters to modify tissue enzyme levels without affecting specific targeting and relative biodistribution. We coupled a-galactosidase (aGal; affected in Fabry disease) to model polymer nanocarriers and varied enzyme load (50 vs. 500 molecules/particle), anti-ICAM surface density (80 vs. 180 molecules/particle), and nanocarrier concentration (1.6 x 1013 vs. 2.4 x 1013 carriers/kg) to render three formulations (45, 449, 555 microg alphaGal/kg). Naked alpha Gal preferentially distributed in blood vs. organs, while nanocarriers shifted biodistribution from blood to tissues. Accumulation in brain, kidneys, heart, liver, lungs, and spleen did not vary among nanocarrier formulations, with enhanced specific tissue accumulation compared to naked aGal. The highest specificity was associated with lowest antibody density and nanocarrier concentration, but highest enzyme load; possibly because of synergistic enzyme affinity toward cell-surface markers. Variation of these parameters significantly increased absolute enzyme accumulation. This strategy may help optimize delivery of lysosomal enzyme replacement and, likely, other protein delivery approaches.

  20. Hyaluronic acid-coated liposomes for targeted delivery of paclitaxel, in-vitro characterization and in-vivo evaluation.

    PubMed

    Ravar, Fatemeh; Saadat, Ebrahim; Gholami, Mehdi; Dehghankelishadi, Pouya; Mahdavi, Mehdi; Azami, Samira; Dorkoosh, Farid A

    2016-05-10

    Breast cancer is the leading cause of cancer death in women. Chemotherapy is regarded as the most essential strategy in inhibiting the proliferation of tumor cells. Paclitaxel is a widely used taxane; however, the side effects of available Cremophor-based formulations and also the limitations of passive targeting uncovered an essential need to develop tumor-specific targeted nanocarriers. A hyaluronic acid targeted liposomal formulation of paclitaxel was prepared in which, hyaluronic acid was electrostatistically attracted to the surface of liposomes. Liposomes, had a particle size of 106.4±3.2nm, a weakly negative zeta potential of -9.7±0.8mV and an acceptable encapsulation efficiency of 92.1±1.7%. The release profile of liposomes in buffer showed that 95% of PTX was released during 40h. Confocal laser scanning microscopy and flow cytometry analysis showed the greater cellular internalization of coumarin-loaded liposomes compared to free coumarin. MTT assay on 4T1 and T47D cells demonstrated the stronger cytotoxic activity of liposomes in comparison to free paclitaxel. Cell cycle analysis showed that cells were mainly blocked at G2/M phases after 48h treatment with liposomes. In vivo real time imaging on 4T1 tumor-bearing mice revealed that the liposomal formulation mainly accumulated in the tumor area. Liposomes also had better antitumor efficacy against Cremophor-based formulation. In conclusion, hyaluronic acid targeted paclitaxel liposome can serve as a promising targeted formulation of paclitaxel for future cancer chemotherapy.

  1. Utility of the summation chromatographic peak integration function to avoid manual reintegrations in the analysis of targeted analytes

    USDA-ARS?s Scientific Manuscript database

    As sample preparation and analytical techniques have improved, data handling has become the main limitation in automated high-throughput analysis of targeted chemicals in many applications. Conventional chromatographic peak integration functions rely on complex software and settings, but untrustwor...

  2. Vacuum plasma spray coating

    NASA Technical Reports Server (NTRS)

    Holmes, Richard R.; Mckechnie, Timothy N.

    1989-01-01

    Currently, protective plasma spray coatings are applied to space shuttle main engine turbine blades of high-performance nickel alloys by an air plasma spray process. Originally, a ceramic coating of yttria-stabilized zirconia (ZrO2.12Y2O3) was applied for thermal protection, but was removed because of severe spalling. In vacuum plasma spray coating, plasma coatings of nickel-chromium-aluminum-yttrium (NiCrAlY) are applied in a reduced atmosphere of argon/helium. These enhanced coatings showed no spalling after 40 MSFC burner rig thermal shock cycles between 927 C (1700 F) and -253 C (-423 F), while current coatings spalled during 5 to 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2.8Y2O3 to the turbine blades of first-stage high-pressure fuel turbopumps utilizing the enhanced NiCrAlY bond-coating process. NiCrAlY bond coating is applied first, with ZrO2.8Y2O3 added sequentially in increasing amounts until a thermal barrier coating is obtained. The enchanced thermal barrier coating has successfully passed 40 burner rig thermal shock cycles.

  3. Polarization Utilization in Radar Target Reconstruction: C-Wide (Multi-Frequency) Band Relationship of a Target’s Characteristic Operators with Its Unique Set of Natural Eigenfrequencies.

    DTIC Science & Technology

    1983-12-14

    Weapons Center, China Lake , CA, 1983. J.R. Huynen, "Phenomenological Theory of Radar Targets," Ph.D. Dissertation, Technical University, Delft, The...Eaves Georgia Institute of Technology Dr. William A. Holm Atlanta, GA 30332 (404) 424-9609 Dr. Otto E. Rausch Electromagnetics Research Lab Dr. Georges A...Sudbury, MA 01776 Bell Aerospace Tektronix Dr. Lionel Shub P.O. Box 1 (716) 297-1000 Buffalo, NY 14240 Raytheon Company Dr. Edwin R. Hiller Hartwell

  4. Optimal design and characterization of superparamagnetic iron oxide nanoparticles coated with polyvinyl alcohol for targeted delivery and imaging.

    PubMed

    Mahmoudi, Morteza; Simchi, Abdolreza; Imani, Mohammad; Milani, Abbas S; Stroeve, Pieter

    2008-11-20

    Superparamagnetic iron oxide nanoparticles (SPION) with narrow size distribution and stabilized by polyvinyl alcohol (PVA) were synthesized. The particles were prepared by a coprecipitation technique using ferric and ferrous salts with a molar Fe3+/Fe2+ ratio of 2. Using a design of experiments (DOE) approach, the effect of different synthesis parameters (stirring rate and base molarity) on the structure, morphology, saturation magnetization, purity, size, and size distribution of the synthesized magnetite nanoparticles was studied by various analysis techniques including X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) with differential scanning calorimetry (DSC) measurements, vibrating-sample magnetometer (VSM), transmission electron microscopy (TEM), UV-visible, and Fourier transform infrared (FT-IR) spectrometer. PVA not only stabilized the colloid but also played a role in preventing further growth of SPION followed by the formation of large agglomerates by chemisorption on the surface of particles. A rich behavior in particle size, particle formation, and super paramagnetic properties is observed as a function of molarity and stirring conditions. The particle size and the magnetic properties as well as particle shape and aggregation (individual nanoparticles, magnetic beads, and magnetite colloidal nanocrystal clusters (CNCs) are found to be influenced by changes in the stirring rate and the base molarity. The formation of magnetic beads results in a decrease in the saturation magnetization, while CNCs lead to an increase in saturation magnetization. On the basis of the DOE methodology and the resulting 3-D response surfaces for particle size and magnetic properties, it is shown that optimum regions for stirring rate and molarity can be obtained to achieve coated SPION with desirable size, purity, magnetization, and shape.

  5. Novel Strategy Utilizing Extracellular Cysteine-Rich Domain of Membrane Receptor for Constructing d-Peptide Mediated Targeted Drug Delivery Systems: A Case Study on Fn14.

    PubMed

    Li, Zhuoxuan; Xie, Jing; Peng, Shan; Liu, Sha; Wang, Ying; Lu, Weiyue; Shen, Jie; Li, Chong

    2017-08-16

    The development of proteolysis-resistant d-peptide ligands for targeted drug/gene delivery has been greatly limited, due to the challenge that lies in the chemical synthesis of membrane receptors without altering their structures. In the present research, a novel strategy utilizing self-stabilized extracellular CRD of the membrane receptor was developed to construct d-peptide ligands and their mediated targeted drug delivery systems. Fn14, a cell surface receptor overexpressed in many cancers including pancreatic and triple-negative breast cancers, was selected as the model receptor. Fn14 CRD was synthesized and folded, and used to screen Fn14 binding peptides using phage display (l-peptide) and mirror-image phage display (d-peptide) techniques, respectively. The d-peptide ligand successfully mediated targeted drug delivery to Fn14 positive tumor cells. In addition, the d-peptide possessed better target-binding affinity, stromal barrier permeability, and tumor targeting ability in vivo when conjugated with liposomes. More importantly, d-peptide mediated liposomal paclitaxel delivery significantly inhibited pancreatic tumor growth in a subcutaneous xenograft model and drastically prolonged survival in a lung metastasis of breast cancer mouse model. This study demonstrated that mirror-image phage display based on the CRD of membrane receptor can be a promising strategy to advance active targeted drug delivery via biostable d-peptides.

  6. SRL-Coated PAMAM Dendrimer Nano-Carrier for Targeted Gene Delivery to the Glioma Cells and Competitive Inhibition by Lactoferrin.

    PubMed

    Zarebkohan, Amir; Najafi, Farhood; Moghimi, Hamid Reza; Hemmati, Mohammad; Deevband, Mohammad Reza; Kazemi, Bahram

    2016-01-01

    Glioma, as a primary tumor of central nervous system, is the main cause of death in patients with brain cancer. Therefore, development of an efficient strategy for treatment of glioma is worthy. The aim of the current study was to develop a SRL peptide-coated dendrimer as a novel dual gene delivery system for targeting the LRP receptor, an up-regulated gene in both BBB and glioma cells. To perform this investigation, our newly developed nanocarrier (PAMAM-PEG-SRL) was used for gene delivery to C6 glioma cell lines. DNA (GFP) was loaded in these functionalized nanoparticles and their cellular uptake/distribution and gene transfection efficacy was evaluated by fluorescence and confocal microscopy. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy. Results revealed improved gene transfection efficiency of newly-synthesized delivery system. We also found that lactoferrin, as a LRP ligand, reduced the gene transfection efficacy of the delivery system due to its higher affinity compared to SRL peptides (Competitive inhibition). The present results suggest that the synthesized delivery system has the potential to be used as an alternative targeted drug delivery system for brain tumors.

  7. EpCAM aptamer-functionalized polydopamine-coated mesoporous silica nanoparticles loaded with DM1 for targeted therapy in colorectal cancer

    PubMed Central

    Bao, Shiyun; He, Lisheng; Ling, Kai; Luo, Jinfeng; Zhang, Yue; Huang, Hao; Zhang, Han; Yu, Xiaofang

    2017-01-01

    DM1, a maytansine derivative, is a highly potential cytotoxic agent but with severe side effects; therefore, its application in clinical cancer therapy is limited. Here, in order to mitigate this intrinsic drawback of DM1, we developed mesoporous silica nanoparticles (MSNs) loaded with DM1 and surface-decorated with hydrochloride dopamine (PDA), polyethylene glycol (PEG), and epithelial cell adhesion molecule (EpCAM) aptamer (APt) for the targeted treatment of colorectal cancer (CRC). In this system, the PDA coating could be used as pH-sensitive gatekeepers to control the release of DM1 from MSNs in response to the pH stimulus and EpCAM APt-guided active targeting enables the increased delivery of DM1 to CRC as well as a reduction in toxicity and side effects by minimizing the exposure of normal tissues to DM1. Results demonstrated that DM1 inhibited the formation of microtubules and induced apoptosis in tumor cells via caspase signaling. In comparison with the control groups, the MSNs-DM1@PDA-PEG-APt bioconjugates exhibited increased binding ability and much higher cytotoxicity to the CRC SW480 cell line. Furthermore, in vivo assays confirmed the advantages of such a strategy. These findings suggested that MSNs-DM1@PDA-PEG-APt could represent a promising therapeutic platform for EpCAM-positive CRC. PMID:28894364

  8. Poly (dopamine) coated superparamagnetic iron oxide nanocluster for noninvasive labeling, tracking, and targeted delivery of adipose tissue-derived stem cells

    NASA Astrophysics Data System (ADS)

    Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng

    2016-01-01

    Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo.

  9. Multifunctional magnetic co-delivery system coated with polymer mPEG-PLL-FA for nasopharyngeal cancer targeted therapy and MR imaging.

    PubMed

    Li, Hailiang; Fu, Chaoping; Miao, Xiangwan; Li, Quanming; Zhang, Juan; Yang, Huikang; Liu, Tao; Chen, Xi; Xie, Minqiang

    2017-03-01

    The gene and drug co-delivery system has become one of the primary strategies to overcome cancers. Here, we designed a multifunctional magnetic co-delivery system for nasopharyngeal carcinoma-targeted therapy and MR imaging. Aldehyde sodium alginate (ASA) was used to decorate the oxide iron and load cisplain through coordinate bond to form a core complex. The polymer shell poly(l-lysine)-methoxy-polyethylene glycol-folate was used to coat the core complex through electric interaction to give this nano-medicine a target ability. And this polymer could also give the nano-medicine abilities to adhere and protect DNA, and enhance its solubleness in water. After being transfected with this nano-medicine, the plasmids which contain cancer suppressor gene TFPI2 could enter and express in HNE-1 cells. It caused a higher death and apoptosis rate, inhibited nasopharyngeal carcinoma cells' migration and cloning by the synergic effect together with cisplain. Besides, clear images of this nano-medicine could be got under T2 MR imaging. This magnetic co-delivery system demonstrates a potential as a powerful multifunctional vector for drug delivery and gene vector applications in nasopharyngeal carcinoma.

  10. Myosin VI targeting to clathrin-coated structures and dimerisation is mediated by binding to Disabled-2 and PtdIns(4,5)P2

    PubMed Central

    Spudich, Giulietta; Chibalina, Margarita V.; Au, Josephine Sui-Yan; Arden, Susan D.; Buss, Folma; Kendrick-Jones, John

    2009-01-01

    Vesicle transport is essential for the movement of proteins, lipids and other molecules between membrane compartments within the cell. The role of the class VI myosins in vesicular transport is especially intriguing because they are the only class that has been shown to move “backwards” towards the minus end of actin filaments1. Myosin VI is found in distinct intracellular locations and implicated in processes such as endocytosis2,3, exocytosis, maintenance of Golgi morphology4,5 and cell movement6. We have shown that the C-terminal tail is the key targeting region and have identified three binding sites: a WWY motif for Dab2 binding, a RRL motif for GIPC/Optineurin binding and a site that binds specifically and with high affinity (Kd 0.3 μM) to PIP2-containing liposomes. This is the first demonstration that myosin VI binds lipid membranes. Lipid binding induces a large structural change in the tail (31% increase in helicity) and when associated with lipid vesicles it can dimerise. In vivo targeting and recruitment of myosin VI to clathrin-coated structures (CCSs) at the plasma membrane is mediated by Dab2 and PIP2 binding. PMID:17187061

  11. Poly (dopamine) coated superparamagnetic iron oxide nanocluster for noninvasive labeling, tracking, and targeted delivery of adipose tissue-derived stem cells.

    PubMed

    Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng

    2016-01-05

    Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo.

  12. EpCAM aptamer-functionalized polydopamine-coated mesoporous silica nanoparticles loaded with DM1 for targeted therapy in colorectal cancer.

    PubMed

    Li, Yang; Duo, Yanhong; Bao, Shiyun; He, Lisheng; Ling, Kai; Luo, Jinfeng; Zhang, Yue; Huang, Hao; Zhang, Han; Yu, Xiaofang

    2017-01-01

    DM1, a maytansine derivative, is a highly potential cytotoxic agent but with severe side effects; therefore, its application in clinical cancer therapy is limited. Here, in order to mitigate this intrinsic drawback of DM1, we developed mesoporous silica nanoparticles (MSNs) loaded with DM1 and surface-decorated with hydrochloride dopamine (PDA), polyethylene glycol (PEG), and epithelial cell adhesion molecule (EpCAM) aptamer (APt) for the targeted treatment of colorectal cancer (CRC). In this system, the PDA coating could be used as pH-sensitive gatekeepers to control the release of DM1 from MSNs in response to the pH stimulus and EpCAM APt-guided active targeting enables the increased delivery of DM1 to CRC as well as a reduction in toxicity and side effects by minimizing the exposure of normal tissues to DM1. Results demonstrated that DM1 inhibited the formation of microtubules and induced apoptosis in tumor cells via caspase signaling. In comparison with the control groups, the MSNs-DM1@PDA-PEG-APt bioconjugates exhibited increased binding ability and much higher cytotoxicity to the CRC SW480 cell line. Furthermore, in vivo assays confirmed the advantages of such a strategy. These findings suggested that MSNs-DM1@PDA-PEG-APt could represent a promising therapeutic platform for EpCAM-positive CRC.

  13. Percutaneous angioplasty using a paclitaxel-coated balloon improves target lesion restenosis on inflow lesions of autogenous radiocephalic fistulas: a pilot study.

    PubMed

    Lai, Chi-Cheng; Fang, Hua-Chang; Tseng, Ching-Jiunn; Liu, Chun-Peng; Mar, Guang-Yuan

    2014-04-01

    To determine whether the use of a paclitaxel-coated balloon (PCB) improves patency in patients undergoing percutaneous transluminal angioplasty (PTA) for recurrent juxtaanastomotic stenosis of radiocephalic arteriovenous fistulas (RCAVFs). This prospective study recruited hemodialysis patients with two short (< 2 cm) and separated inflow RCAVF lesions. After dilation of lesions using a 4-mm plain balloon (PB), half of the lesions were randomly selected for treatment with PTA using PCB (size, 4 mm; length, 2 cm) and PB (size, 5-mm or 6-mm) (group 1), and the other half were treated with PTA using PB alone (group 2). After the index PTA, dysfunction-driven angiography was performed to confirm target lesion restenosis (TLR). TLR and lesion patency were compared in the two groups by χ(2) test, t test, and Kaplan-Meier analysis. The analysis of 20 lesions in 10 patients revealed that the TLR-free duration in group 1 was significantly longer than the TLR-free duration in group 2 (251.2 d vs 103.2 d; P < .01). The patency rate of the target lesion was significantly higher in group 1 than in group 2 at 6 months (70% vs 0%; P < .01) but not at 12 months (20% vs 0%; P > .05). This early study suggests that, for improving short-term patency, PTA with PCB and PB is more effective than PTA with PB alone, warranting further study. Copyright © 2014. Published by Elsevier Inc.

  14. Poly (dopamine) coated superparamagnetic iron oxide nanocluster for noninvasive labeling, tracking, and targeted delivery of adipose tissue-derived stem cells

    PubMed Central

    Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng

    2016-01-01

    Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo. PMID:26728448

  15. SRL-Coated PAMAM Dendrimer Nano-Carrier for Targeted Gene Delivery to the Glioma Cells and Competitive Inhibition by Lactoferrin

    PubMed Central

    zarebkohan, Amir; Najafi, Farhood; Moghimi, Hamid Reza; Hemmati, Mohammad; Deevband, Mohammad Reza; Kazemi, Bahram

    2016-01-01

    Glioma, as a primary tumor of central nervous system, is the main cause of death in patients with brain cancer. Therefore, development of an efficient strategy for treatment of glioma is worthy. The aim of the current study was to develop a SRL peptide-coated dendrimer as a novel dual gene delivery system for targeting the LRP receptor, an up-regulated gene in both BBB and glioma cells. To perform this investigation, our newly developed nanocarrier (PAMAM-PEG-SRL) was used for gene delivery to C6 glioma cell lines. DNA (GFP) was loaded in these functionalized nanoparticles and their cellular uptake/distribution and gene transfection efficacy was evaluated by fluorescence and confocal microscopy. In vitro studies showed that SRL-modified nanoparticles have good transfection efficacy. Results revealed improved gene transfection efficiency of newly-synthesized delivery system. We also found that lactoferrin, as a LRP ligand, reduced the gene transfection efficacy of the delivery system due to its higher affinity compared to SRL peptides (Competitive inhibition). The present results suggest that the synthesized delivery system has the potential to be used as an alternative targeted drug delivery system for brain tumors. PMID:28243262

  16. M-L band x-rays (3-3.5 KeV) from palladium coated targets for isochoric radiative heating of thin foil samples

    NASA Astrophysics Data System (ADS)

    Kettle, B.; Dzelzainis, T.; White, S.; Li, L.; Rigby, A.; Spindloe, C.; Notley, M.; Heathcote, R.; Lewis, C. L. S.; Riley, D.

    2015-11-01

    We describe experiments designed to produce a bright M-L band x-ray source in the 3-3.5 keV region. Palladium targets irradiated with a 1015 W cm-2 laser pulse have previously been shown to convert up to ˜2% of the laser energy into M-L band x-rays with similar pulse duration to that of the incident laser. This x-ray emission is further characterized here, including pulse duration and source size measurements, and a higher conversion efficiency than previously achieved is demonstrated (˜4%) using more energetic and longer duration laser pulses (200 ps). The emission near the aluminium K-edge (1.465-1.550 keV) is also reported for similar conditions, along with the successful suppression of such lower band x-rays using a CH coating on the rear side of the target. The possibility of using the source to radiatively heat a thin aluminium foil sample to uniform warm dense matter conditions is discussed.

  17. CD44-Targeted Hyaluronic Acid-Coated Redox-Responsive Hyperbranched Poly(amido amine)/Plasmid DNA Ternary Nanoassemblies for Efficient Gene Delivery.

    PubMed

    Gu, Jijin; Chen, Xinyi; Ren, Xiaoqing; Zhang, Xiulei; Fang, Xiaoling; Sha, Xianyi

    2016-07-20

    Hyaluronic acid (HA), which can specifically bind to CD44 receptor, is a specific ligand for targeting to CD44-overexpressing cancer cells. The current study aimed to develop ternary nanoassemblies based on HA-coating for targeted gene delivery to CD44-positive tumors. A novel reducible hyperbranched poly(amido amine) (RHB) was assembled with plasmid DNA (pDNA) to form RHB/pDNA nanoassemblies. HA/RHB/pDNA nanoassemblies were fabricated by coating HA on the surface of the RHB/pDNA nanoassembly core through electrostatic interaction. After optimization, HA/RHB/pDNA nanoassemblies were spherical, core-shell nanoparticles with nanosize (187.6 ± 11.4 nm) and negative charge (-9.1 ± 0.3 mV). The ternary nanoassemblies could efficiently protect the condensed pDNA from enzymatic degradation by DNase I, and HA could significantly improve the stability of nanoassemblies in the sodium heparin solution or serum in vitro. As expected, HA significantly decreased the cytotoxicity of RHB/pDNA nanoassemblies due to the negative surface charges. Moreover, it revealed that HA/RHB/pDNA nanoassemblies showed higher transfection activity than RHB/pDNA nanoassemblies in B16F10 cells, especially in the presence of serum in vitro. Because of the active recognition between HA and CD44 receptor, there was significantly different transfection efficiency between B16F10 (CD44+) and NIH3T3 (CD44-) cells after treatment with HA/RHB/pDNA nanoassemblies. In addition, the cellular targeting and transfection activity of HA/RHB/pDNA nanoassemblies were further evaluated in vivo. The results indicated that the interaction between HA and CD44 receptor dramatically improved the accumulation of HA/RHB/pDNA nanoassemblies in CD44-positive tumor, leading to higher gene expression than RHB/pDNA nanoassemblies. Therefore, HA/RHB/pDNA ternary nanoassemblies may be a potential gene vector for delivery of therapeutic genes to treat CD44-overexpressing tumors in vivo.

  18. Evolutionary selection of new breast cancer cell-targeting peptides and phages with the cell-targeting peptides fully displayed on the major coat and their effects on actin dynamics during cell internalization

    PubMed Central

    Abbineni, Gopal; Modali, Sita; Safiejko-Mroczka, Barbara; Petrenko, Valery A.; Mao, Chuanbin

    2010-01-01

    Filamentous phage as a bacteria-specific virus can be conjugated with an anti-cancer drug and has been proposed to serve as a carrier to deliver drugs to cancer cells for targeted therapy. However, how cell-targeting filamentous phage alone affects cancer cell biology is unclear. Phage libraries provide an inexhaustible reservoir of new ligands against tumor cells and tissues that have potential therapeutic and diagnostic applications in cancer treatment. Some of these identified ligands might stimulate various cell responses. Here we identified new cell internalizing peptides (and the phages with such peptides fused to each of ~3900 copies of their major coat protein) using landscape phage libraries and for the first time investigated the actin dynamics when selected phages are internalized into the SKBR-3 breast cancer cells. Our results show that phages harboring VSSTQDFP and DGSIPWST peptides could selectively internalize into the SKBR-3 breast cancer cells with high affinity, and also show rapid involvement of membrane ruffling and re-arrangements of actin cytoskeleton during the phage entry. The actin dynamics was studied by using live cell and fluorescence imaging. The cell-targeting phages were found to enter breast cancer cells through energy dependent mechanism and phage entry interferes with actin dynamics, resulting in reorganization of actin filaments and increased membrane rufflings in SKBR-3 cells. These results suggest that, when phage enters epithelial cells, it triggers transient changes in the host cell actin cytoskeleton. This study also shows that using multivalent phage libraries considerably increases the repertoire of available cell-internalizing ligands with potential applications in targeted drug delivery, imaging, molecular monitoring and profiling of breast cancer cells. PMID:20735141

  19. Transferrin-conjugated lipid-coated PLGA nanoparticles for targeted delivery of aromatase inhibitor 7α-APTADD to breast cancer cells

    PubMed Central

    Zheng, Yu; Yu, Bo; Weecharangsan, Wanlop; Piao, Longzhu; Darby, Michael; Mao, Yicheng; Koynova, Rumiana; Yang, Xiaojuan; Li, Hong; Xu, Songlin; Lee, L. James; Sugimoto, Yasuro; Brueggemeier, Robert W.; Lee, Robert J.

    2013-01-01

    Transferrin (Tf)-conjugated lipid-coated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles carrying the aromatase inhibitor, 7α-(4′-amino)phenylthio-1,4-androstadiene-3,17-dione (7α-APTADD), were synthesized by a solvent injection method. Formulation parameters including PLGA-to-lipid, egg PC-to-TPGS, and drug-to-PLGA ratios and aqueous-to-organic phase ratio at the point of synthesis were optimized to obtain nanoparticles with desired sizes and drug loading efficiency. The optimal formulation had a drug loading efficiency of 36.3±3.4%, mean diameter of 170.3±7.6 nm and zeta potential of −18.9±1.5 mV. The aromatase inhibition activity of the nanoparticles was evaluated in SKBR-3 breast cancer cells. IC50 value of the Tf-nanoparticles was ranging from 0.77 to 1.21 nM, and IC50 value of the nanoparticles was ranging from 1.90 to 3.41 nM (n = 3). The former is significantly lower than the latter (p < 0.05). These results suggested that the aromatase inhibition activity of the Tf-nanoparticles was enhanced relative to that of the non-targeted nanoparticles, which was attributable to Tf receptor (TfR) mediated uptake. In conclusion, Tf-conjugated lipid-coated PLGA nanoparticles are potential vehicles for improving the efficiency and specificity of therapeutic delivery of aromatase inhibitors. PMID:20156537

  20. 6SLN-lipo PGA specifically catches (coats) human influenza virus and synergizes neuraminidase-targeting drugs for human influenza therapeutic potential.

    PubMed

    Sriwilaijaroen, Nongluk; Suzuki, Katsuhiko; Takashita, Emi; Hiramatsu, Hiroaki; Kanie, Osamu; Suzuki, Yasuo

    2015-10-01

    The purpose of this study was to develop a new compound to overcome influenza epidemics and pandemics as well as drug resistance. We synthesized a new compound carrying: (i) Neu5Acα2-6Galβ1-4GlcNAc (6SLN) for targeting immutable haemagglutinins (HAs) unless switched from human-type receptor preference; (ii) an acyl chain (lipo) for locking the compound with the viral HA via hydrophobic interactions; and (iii) a flexible poly-α-L-glutamic acid (PGA) for enhancing the compound solubility and for coating the viral surface, precluding accessibility of the PGA-coated virus to the negatively charged sialic acid on the host cell surface. 6SLN-lipo PGA appears to subvert binding of pandemic H1 and seasonal H3 HAs to receptors, as assessed by using guinea pig erythrocytes, which is critical for virus entry into host cells for multiplication. It shows high potency with IC50 values in the range of 300-500 nM against multiplication of both influenza pandemic H1N1/2009 and seasonal H3N2/2004 viruses in cell culture. It acts in synergism with either of the two FDA-approved neuraminidase inhibitor (NAI) clinical drugs, zanamivir (Relenza(®)) and oseltamivir carboxylate (active form of Tamiflu(®)), and it has the potential to aid NAI drugs to achieve complete clearance of the virus from the culture. 6SLN-lipo PGA is a new potential candidate drug for influenza control and is an attractive candidate for use in combination with an NAI drug for minimized toxicity, delayed development of resistance, prevention and treatment with the potential for eradication of human influenza. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Clinical Application of Targeted Deep Sequencing in Solid-Cancer Patients; Utility of Targeted Deep Sequencing for Biomarker-Selected Clinical Trial.

    PubMed

    Kim, Seung Tae; Kim, Kyoung-Mee; Kim, Nayoung K D; Park, Joon Oh; Ahn, Soomin; Yun, Jae-Won; Kim, Kyu-Tae; Park, Se Hoon; Park, Peter J; Kim, Hee Cheol; Sohn, Tae Sung; Choi, Dong Il; Cho, Jong Ho; Heo, Jin Seok; Kwon, Wooil; Lee, Hyuk; Min, Byung-Hoon; Hong, Sung No; Park, Young Suk; Lim, Ho Yeong; Kang, Won Ki; Park, Woong-Yang; Lee, Jeeyun

    2017-07-12

    Molecular profiling of actionable mutations in refractory cancer patients has the potential to enable "precision medicine," wherein individualized therapies are guided based on genomic profiling. The molecular-screening program was intended to route participants to different candidate drugs in trials based on clinical-sequencing reports. In this screening program, we used a custom target-enrichment panel consisting of cancer-related genes to interrogate single-nucleotide variants, insertions and deletions, copy number variants, and a subset of gene fusions. From August 2014 through April 2015, 654 patients consented to participate in the program at Samsung Medical Center. Of these patients, 588 passed the quality control process for the 381-gene cancer-panel test, and 418 patients were included in the final analysis as being eligible for any anticancer treatment (127 gastric cancer, 122 colorectal cancer, 62 pancreatic/biliary tract cancer, 67 sarcoma/other cancer, and 40 genitourinary cancer patients). Of the 418 patients, 55 (12%) harbored a biomarker that guided them to a biomarker-selected clinical trial, and 184 (44%) patients harbored at least one genomic alteration that was potentially targetable. This study demonstrated that the panel-based sequencing program resulted in an increased rate of trial enrollment of metastatic cancer patients into biomarker-selected clinical trials. Given the expanding list of biomarker-selected trials, the guidance percentage to matched trials is anticipated to increase. This study demonstrated that the panel-based sequencing program resulted in an increased rate of trial enrollment of metastatic cancer patients into biomarker-selected clinical trials. Given the expanding list of biomarker-selected trials, the guidance percentage to matched trials is anticipated to increase. © AlphaMed Press 2017.

  2. Utilization of carrageenan, citric acid and cinnamon oil as an edible coating of chicken fillets to prolong its shelf life under refrigeration conditions

    PubMed Central

    Khare, Anshul Kumar; Abraham, Robinson J. J.; Appa Rao, V.; Babu, R. Narendra

    2016-01-01

    Aim: The present study was conducted to determine efficacy of edible coating of carrageenan and cinnamon oil to enhance the shelf life of chicken meat stored under refrigeration conditions. Materials and Methods: Chicken breast was coated with carrageenan and cinnamon oil by three methods of application viz., spraying brushing and dipping. The coated meat was evaluated for drip loss, pH, thiobarbituric acid number (TBA), tyrosine value (TV), extract release volume (ERV), Warner-Bratzler shear force value (WBSFV), instrumental color, microbiological, and sensory qualities as per standard procedures. Results: There was a significant difference observed for physicochemical parameters (pH, TBA, TV, ERV, drip loss and WBSFV) and microbiological analysis between storage periods in all the samples and between the control and treatments throughout the storage period but samples did not differed significantly for hunter color scores. However, there was no significant difference among three methods of application throughout the storage period though dipping had a lower rate of increase. A progressive decline in mean sensory scores was recorded along with the increase in storage time. Conclusion: The carrageenan and cinnamon edible coating was found to be a good alternative to enhance the shelf life of chicken meat under refrigeration conditions. It was also observed from study that dipping method of the application had comparatively higher shelf life than other methods of application. PMID:27051203

  3. Development of Sialic Acid-coated Nanoparticles for Targeting Cancer and Efficient Evasion of the Immune System

    PubMed Central

    Kim, Young-Hwa; Min, Kyung Hyun; Wang, Zhantong; Kim, Jihoon; Jacobson, Orit; Huang, Peng; Zhu, Guizhi; Liu, Yijing; Yung, Bryant; Niu, Gang; Chen, Xiaoyuan

    2017-01-01

    Evading the reticuloendothelial system (RES) remains a critical challenge in the development of efficient delivery and diagnostic systems for cancer. Sialic acid (N-acetylneuraminic acid, Neu5Ac) is recognized as a “self” marker by major serum protein complement factor H and shows reduced interaction with the innate immune system via sialic acid-binding immunoglobulin-like lectin (Siglec), which is known as one of the significant regulators of phagocytic evasion. Accordingly, we prepared different surface-modified gold nanoparticles (AuNPs) and investigated the effects of sialic acid on cellular and immune responses of nanoparticles in vitro and in vivo. Sialic acid modification not only facilitates evasion of the RES by suppressing the immune response, but also enhances tumor accumulation via its active targeting ability. Therefore, sialic acid modification presents a promising strategy to advance nanotechnology towards the prospect of clinical translation. PMID:28382168

  4. Tailored coatings for hardfacing

    SciTech Connect

    Dustoor, M.R.; Moskowitz, L.N.

    1984-01-01

    An update on Conforma Clad coatings, first presented at the 1982 National Powder Metallurgy Conference in Montreal, Canada, is presented. The major advantage is the ability to offer selective-area coatings in a wide range of thicknesses and material choices while retaining dimensional and edge control of the coating. Complex geometries can be coated with a high materials utilization and with coating properties tailored to the end application. Porosity and bond strength values can match or exceed those seen with the best commercially available thermal sprayed coatings. The ability of the process to balance abrasion resistance and toughness requirements for a specific wear mode, is illustrated by microstructural control of the size, shape and density of carbide particles contained in the coatings. Dry sand abrasive test data are provided on Conforma Clad coatings and competitive processes. Ongoing developments of non-furnace fusion techniques, such as laser cladding, are presented and the microstructures compared with those obtained with conventional coating processes. Commercial applications for these coatings are highlighted with some typical examples.

  5. Progress Toward Meeting NIF Specifications for Vapor Deposited Polyimide Ablator Coatings

    SciTech Connect

    Letts, Stephan A.; Anthamatten, Mitchell; Buckley, Steven R.; Fearon, Evelyn; Nissen, April E.H.; Cook, Robert C.

    2004-03-15

    We are developing an evaporative coating technique for deposition of thick polyimide (PI) ablator layers on ICF targets. The PI coating technique utilizes stoichiometrically controlled fluxes from two Knudsen cell evaporators containing a dianhydride and a diamine to deposit a polyamic acid (PAA) coating. Heating the PAA coating to 300 deg. C converts the PAA coating to a polyimide. Coated shells are rough due to particles on the substrate mandrels and from damage to the coating caused by the agitation used to achieve a uniform coating. We have developed a smoothing process that exposes an initially rough PAA coated shell to solvent vapor using gas levitation. We found that after smoothing the coatings developed a number of wide (low-mode) defects. We have identified two major contributors to low-mode roughness: surface hydrolysis, and deformation during drying/curing. By minimizing air exposure prior to vapor smoothing, avoiding excess solvent sorption during vapor smoothing, and using slow drying we are able to deposit and vapor smooth coatings 160 {mu}m thick with a surface roughness less than 20 nm RMS.

  6. Target adjustment and self-other agreement: utilizing trait observability to disentangle judgeability and self-knowledge.

    PubMed

    Human, Lauren J; Biesanz, Jeremy C

    2011-07-01

    Are well-adjusted individuals good targets or accurate self-judges? Across two round-robin studies, the current research first demonstrates that well-adjusted individuals' personalities are viewed with greater distinctive self-other agreement by new acquaintances. Is this enhanced self-other agreement a function of greater judgeability, improving others' ability to form an accurate impression? Or is it a function of greater self-knowledge, having a more accurate impression about oneself? By examining the relationship between psychological adjustment and self-other agreement as a function of trait observability, it becomes clear that psychological adjustment fosters self-other agreement through judgeability more so than through self-knowledge. Specifically, well-adjusted individuals provide new acquaintances with greater information regarding their less observable traits, enhancing others' knowledge and thus distinctive self-other agreement. This effect was replicated with close informant-other agreement, indicating that the well-adjusted individual's tendency to make his or her less visible traits more accessible to others allows those who just met the target to agree better with people who know the target well. In sum, although well-adjusted individuals are in part good self-judges, it is their greater judgeability that seems most critical in enhancing self-other agreement in first impressions. PsycINFO Database Record (c) 2011 APA, all rights reserved.

  7. SU-E-T-600: Utilizing Collimator Rotation to Increase Maximum Treatable Target Dimensions Using an Elekta Synergy-S with Beam Modulator Multileaf Collimator.

    PubMed

    Rhodes, C; Campbell, S; Shields, W; Fabien, J; Colussi, V; Wessels, B

    2012-06-01

    To determine if a rotated collimator on an Elekta Synergy-S with Beam Modulator MLC (BMx) allows for dosimetrically acceptable treatment of targets exceeding the length of the maximum field size (21×16cm). The BMx is a high-resolution MLC with 4mm leaves but is of limited clinical use on patient target volumes exceeding 20cm in length. Rotation of the collimator utilizes the Pythagorean geometry to extend treatment length. This potentially increases the length of the PTV that be conformally treated. Rods of 21-23cm length were contoured in water with the Pinnacle treatment planning system. The width of the rods varies from 1 -5cm. Four isocentric treatment plans were generated for each target: four-field conformal, 7-field IMRT, single-arc VMAT, and a modified double-arc VMAT (MDAV), with the collimator angled at 55°. The MDAV method consists of two opposing 180° arcs with the collimator turned 55° in opposite directions. A successful plan is defined as 99% of the target volume being covered by a minimum of 95% of the prescribed dose. Conformality is determined as a ratio of the volume exposed to prescribed isodose and target volume. Targets of length 21cm, 22cm, and 23 cm are able to be treated with widths of 4cm, 5 cm, and 4cm respectively. The MDAV method achieves these results on all trials. The VMAT method achieves these results for the 21cm and 23cm long target. The IMRT Method achieves these results for the 21cm long target. With the exception of the 1cm wide targets, the average conformality is approximately 2.5. Changing the collimator angle of the BMx Elekta-S machine allows for a 3cm length increase of targets up to 5cm. Further work will assess clinical suitability of these findings for treatment of head and neck tumors and spinal masses. © 2012 American Association of Physicists in Medicine.

  8. Phase separation in NiCrN coatings induced by N2 addition in the gas phase: A way to generate magnetic thin films by reactive sputtering of a non-magnetic NiCr target

    NASA Astrophysics Data System (ADS)

    Luciu, I.; Duday, D.; Choquet, P.; Perigo, E. A.; Michels, A.; Wirtz, T.

    2016-12-01

    Magnetic coatings are used for a lot of applications from data storage in hard discs, spintronics and sensors. Meanwhile, magnetron sputtering is a process largely used in industry for the deposition of thin films. Unfortunately, deposition of magnetic coatings by magnetron sputtering is a difficult task due to the screening effect of the magnetic target lowering the magnetic field strength of the magnet positioned below the target, which is used to generate and trap ions in the vicinity of the target surface to be sputtered. In this work we present an efficient method to obtain soft magnetic thin films by reactive sputtering of a non-magnetic target. The aim is to recover the magnetic properties of Ni after dealloying of Ni and Cr due to the selective reactivity of Cr with the reactive nitrogen species generated during the deposition process. The effects of nitrogen content on the dealloying and DC magnetron sputtering (DCMS) deposition processes are studied here. The different chemical compositions, microstructures and magnetic properties of DCMS thin films obtained by sputtering in reactive gas mixtures with different ratios of Ar/N2 from a non-magnetic Ni-20Cr target have been determined. XPS data indicate that the increase of nitrogen content in the films has a strong influence on the NiCr phase decomposition into Ni and CrN, leading to ferromagnetic coatings due to the Ni phase. XRD results show that the obtained Ni-CrN films consist of a metallic fcc cubic Ni phase mixed with fcc cubic CrN. The lattice parameter decreases with the N2 content and reaches the theoretical value of the pure fcc-Ni, when Cr is mostly removed from the Ni-Cr phase. Dealloying of Cr from a Ni80-Cr20 solid solution is achieved in our experimental conditions and the deposition of Ni ferromagnetic coatings embedding CrN from a non-magnetic target is possible with reactive DC magnetron sputtering.

  9. Effects of Achieving Target Measures in Rheumatoid Arthritis on Functional Status, Quality of Life, and Resource Utilization: Analysis of Clinical Practice Data.

    PubMed

    Alemao, Evo; Joo, Seongjung; Kawabata, Hugh; Al, Maiwenn J; Allison, Paul D; Rutten-van Mölken, Maureen P M H; Frits, Michelle L; Iannaccone, Christine K; Shadick, Nancy A; Weinblatt, Michael E

    2016-03-01

    To evaluate associations between achieving guideline-recommended targets of disease activity, defined by the Disease Activity Score in 28 joints using C-reactive protein level (DAS28-CRP) <2.6, the Simplified Disease Activity Index (SDAI) ≤3.3, or the Clinical Disease Activity Index (CDAI) ≤2.8, and other health outcomes in a longitudinal observational study. Other defined thresholds included low disease activity (LDA), moderate (MDA), or severe disease activity (SDA). To control for intraclass correlation and estimate effects of independent variables on outcomes of the modified Health Assessment Questionnaire (M-HAQ), the EuroQol 5-domain (EQ-5D; a quality-of-life measure), hospitalization, and durable medical equipment (DME) use, we employed mixed models for continuous outcomes and generalized estimating equations for binary outcomes. Among 1,297 subjects, achievement (versus nonachievement) of recommended disease targets was associated with enhanced physical functioning and lower health resource utilization. After controlling for baseline covariates, achievement of disease targets (versus LDA) was associated with significantly enhanced physical functioning based on SDAI ≤3.3 (ΔM-HAQ -0.047; P = 0.0100) and CDAI ≤2.8 (-0.073; P = 0.0003) but not DAS28-CRP <2.6 (-0.022; P = 0.1735). Target attainment was associated with significantly improved EQ-5D (0.022-0.096; P < 0.0030 versus LDA, MDA, or SDA). Patients achieving guideline-recommended disease targets were 36-45% less likely to be hospitalized (P < 0.0500) and 23-45% less likely to utilize DME (P < 0.0100). Attaining recommended target disease-activity measures was associated with enhanced physical functioning and health-related quality of life. Some health outcomes were similar in subjects attaining guideline targets versus LDA. Achieving LDA is a worthy clinical objective in some patients. © 2016 The Authors. Arthritis Care & Research published by Wiley Periodicals, Inc. on behalf of the

  10. Effects of Achieving Target Measures in Rheumatoid Arthritis on Functional Status, Quality of Life, and Resource Utilization: Analysis of Clinical Practice Data

    PubMed Central

    Joo, Seongjung; Kawabata, Hugh; Al, Maiwenn J.; Allison, Paul D.; Rutten‐van Mölken, Maureen P. M. H.; Frits, Michelle L.; Iannaccone, Christine K.; Shadick, Nancy A.; Weinblatt, Michael E.

    2016-01-01

    Objective To evaluate associations between achieving guideline‐recommended targets of disease activity, defined by the Disease Activity Score in 28 joints using C‐reactive protein level (DAS28‐CRP) <2.6, the Simplified Disease Activity Index (SDAI) ≤3.3, or the Clinical Disease Activity Index (CDAI) ≤2.8, and other health outcomes in a longitudinal observational study. Methods Other defined thresholds included low disease activity (LDA), moderate (MDA), or severe disease activity (SDA). To control for intraclass correlation and estimate effects of independent variables on outcomes of the modified Health Assessment Questionnaire (M‐HAQ), the EuroQol 5‐domain (EQ‐5D; a quality‐of‐life measure), hospitalization, and durable medical equipment (DME) use, we employed mixed models for continuous outcomes and generalized estimating equations for binary outcomes. Results Among 1,297 subjects, achievement (versus nonachievement) of recommended disease targets was associated with enhanced physical functioning and lower health resource utilization. After controlling for baseline covariates, achievement of disease targets (versus LDA) was associated with significantly enhanced physical functioning based on SDAI ≤3.3 (ΔM‐HAQ −0.047; P = 0.0100) and CDAI ≤2.8 (−0.073; P = 0.0003) but not DAS28‐CRP <2.6 (−0.022; P = 0.1735). Target attainment was associated with significantly improved EQ‐5D (0.022–0.096; P < 0.0030 versus LDA, MDA, or SDA). Patients achieving guideline‐recommended disease targets were 36–45% less likely to be hospitalized (P < 0.0500) and 23–45% less likely to utilize DME (P < 0.0100). Conclusion Attaining recommended target disease‐activity measures was associated with enhanced physical functioning and health‐related quality of life. Some health outcomes were similar in subjects attaining guideline targets versus LDA. Achieving LDA is a worthy clinical objective in some patients. PMID:26238974

  11. Spatially resolved characterization of catalyst-coated membranes by distance-controlled scanning mass spectrometry utilizing catalytic methanol oxidation as gas-solid probe reaction.

    PubMed

    Li, Nan; Assmann, Jens; Schuhmann, Wolfgang; Muhler, Martin

    2007-08-01

    The spatially resolved catalytic activity of a catalyst-coated membrane (CCM), which is the essential part of PEM fuel cells, was visualized rapidly without any damage by a distance-controlled scanning mass spectrometer with an improved resolution of 250 microm. Methanol oxidation was identified as a suitable gas-solid probe reaction for the characterization of local catalytic activity. In addition, defects were manually generated in the CCM to simulate inhomogeneous coating and pinholes. The measurements successfully demonstrated that catalytically active and less active regions can be clearly distinguished. Simultaneously, the local topography was recorded, providing additional information on the location of the scratches and pinholes. The catalytic results were highly reproducible due to the constant-distance feedback loop rendering scanning mass spectrometry a promising tool for the quantitative quality control of CCMs.

  12. MAGEA4 expression in bone and soft tissue tumors: its utility as a target for immunotherapy and diagnostic marker combined with NY-ESO-1.

    PubMed

    Iura, Kunio; Kohashi, Kenichi; Ishii, Takeaki; Maekawa, Akira; Bekki, Hirofumi; Otsuka, Hiroshi; Yamada, Yuichi; Yamamoto, Hidetaka; Matsumoto, Yoshihiro; Iwamoto, Yukihide; Oda, Yoshinao

    2017-07-26

    Cancer-testis (CT) antigens have promise as targets for immunotherapy, because of their restricted expression in tumor or testis tissue. MAGEA4 is both a MAGE family member and a CT antigen, and has attracted attention as a potential immunotherapeutic target. We investigated MAGEA4 expression by immunohistochemistry in bone and soft tissue tumor specimens that consisted of 35 malignant or intermediate and 24 benign histological subtypes, in order to evaluate its possible utility as an immunotherapy target and its potential use as a diagnostic marker when combined with another CT antigen, NY-ESO-1. Among these tumors, MAGEA4 was detected in 82.2% of synovial sarcomas, 67.7% of myxoid liposarcomas, 43.8% of osteosarcomas, 41.4% of angiosarcomas, 24.6% of malignant peripheral nerve sheath tumors (MPNSTs), and 21.4% of chondrosarcomas. NY-ESO-1 expression was found in 88.2% of myxoid liposarcomas, 61.1% of synovial sarcomas, 31.3% of osteosarcomas, 21.4% of pleomorphic liposarcomas, 16.7% of desmoplastic small round cell tumors, and 14.3% of chondrosarcomas. Benign tumors and non-tumorous tissue, except for testis tissue, did not express MAGEA4 or NY-ESO-1. Combined use of MAGEA4 and NY-ESO-1 increased the sensitivity, specificity, positive predictive values, and negative predictive values for distinguishing synovial sarcoma from spindle cell tumors and other mimicking tumors, compared to individual use of MAGEA4 or NY-ESO-1. Our results support the immunotherapy targeting MAGEA4 or NY-ESO-1 can be an ancillary therapy in the above-mentioned tumors, and the potential utility of MAGEA4 as an ancillary diagnostic marker for synovial sarcoma combined with NY-ESO-1.

  13. Contrast-enhanced MR imaging of atherosclerosis using citrate-coated superparamagnetic iron oxide nanoparticles: calcifying microvesicles as imaging target for plaque characterization.

    PubMed

    Wagner, Susanne; Schnorr, Jörg; Ludwig, Antje; Stangl, Verena; Ebert, Monika; Hamm, Bernd; Taupitz, Matthias

    2013-01-01

    To evaluate the suitability of citrate-coated very small superparamagnetic iron oxide particles (VSOP) as a contrast agent for identifying inflammation in atherosclerotic lesions using magnetic resonance imaging (MRI). VSOP, which have already been evaluated as a blood pool contrast agent for MR angiography in human clinical trials, were investigated in Watanabe heritable hyper-lipidemic rabbits to determine to what extent their accumulation in atherosclerotic lesions is a function of macrophage density and other characteristics of progressive atherosclerotic plaques. In advanced atherosclerotic lesions, a significant MRI signal loss was found within 1 hour after intravenous administration of VSOP at the intended clinical dose of 0.05 mmol Fe/kg. Histological examinations confirmed correlations between the loss of MRI signal in the vessel wall and the presence of Prussian blue-stained iron colocalized with macrophages in the plaque cap, but surprisingly also with calcifying microvesicles at the intimomedial interface. Critical electrolyte magnesium chloride concentration in combination with Alcian blue stain indicates that highly sulfated glycosaminoglycans are a major constituent of these calcifying microvesicles, which may serve as the key molecules for binding VSOP due to their highly complexing properties. Calcifying microvesicles and macrophages are the targets for intravenously injected VSOP in atherosclerotic plaques, suggesting that VSOP-enhanced MRI may render clinically relevant information on the composition and inflammatory activity of progressive atherosclerotic lesions at risk of destabilization.

  14. Contrast-enhanced MR imaging of atherosclerosis using citrate-coated superparamagnetic iron oxide nanoparticles: calcifying microvesicles as imaging target for plaque characterization

    PubMed Central

    Wagner, Susanne; Schnorr, Jörg; Ludwig, Antje; Stangl, Verena; Ebert, Monika; Hamm, Bernd; Taupitz, Matthias

    2013-01-01

    Objective To evaluate the suitability of citrate-coated very small superparamagnetic iron oxide particles (VSOP) as a contrast agent for identifying inflammation in atherosclerotic lesions using magnetic resonance imaging (MRI). Methods and results VSOP, which have already been evaluated as a blood pool contrast agent for MR angiography in human clinical trials, were investigated in Watanabe heritable hyper-lipidemic rabbits to determine to what extent their accumulation in atherosclerotic lesions is a function of macrophage density and other characteristics of progressive atherosclerotic plaques. In advanced atherosclerotic lesions, a significant MRI signal loss was found within 1 hour after intravenous administration of VSOP at the intended clinical dose of 0.05 mmol Fe/kg. Histological examinations confirmed correlations between the loss of MRI signal in the vessel wall and the presence of Prussian blue-stained iron colocalized with macrophages in the plaque cap, but surprisingly also with calcifying microvesicles at the intimomedial interface. Critical electrolyte magnesium chloride concentration in combination with Alcian blue stain indicates that highly sulfated glycosaminoglycans are a major constituent of these calcifying microvesicles, which may serve as the key molecules for binding VSOP due to their highly complexing properties. Conclusion Calcifying microvesicles and macrophages are the targets for intravenously injected VSOP in atherosclerotic plaques, suggesting that VSOP-enhanced MRI may render clinically relevant information on the composition and inflammatory activity of progressive atherosclerotic lesions at risk of destabilization. PMID:23450179

  15. Site-specific immunochemical methylation assessment from genome DNA utilizing a conformational difference between looped-out target and stacked-in nontarget methylcytosines.

    PubMed

    Kurita, Ryoji; Yanagisawa, Hiroyuki; Yoshioka, Kyoko; Niwa, Osamu

    2015-08-15

    We report the sequence-selective immunochemical discrimination of methylcytosine from genomic DNA that we achieved by utilizing selective antibody binding to a looped-out methylcytosine in a bulge region and without using bisulfite treatment, a methylation-sensitive restriction enzyme, or PCR. First, we investigated the affinity of an anti-methylcytosine antibody for methylcytosine in full match, bulge, mismatch and abasic sites using surface plasmon resonance measurement and a microtiter plate to explore the differences as regards antibody binding to the target methylcytosine. The highest affinity, which was comparable to that in a single strand of DNA, was observed in the bulge region. In particular, no affinity was observed in a full match site. This is because there is no interaction such as hydrogen bond or π-π stacking for the bulged methylcytosine, thus enabling only the target in the bulge to be looped out. Methylated and unmethylated genomic DNA were blended to form a model DNA with which to assess the methylation ratio at a specific site. Fragmented DNA was hybridized with a biotinylated probe DNA, which has a sequence capable of forming a single base bulge at the target. The probe design is simple because it consists solely of the elimination of guanine paired with the target cytosine from a full match sequence. As a result, we successfully obtained a linear relationship (r(2)=0.9962) between the immunoassay signal and the methylation ratio of a specific site within 4 h.

  16. Community-Based Health Education Programs Designed to Improve Clinical Measures Are Unlikely to Reduce Short-Term Costs or Utilization Without Additional Features Targeting These Outcomes.

    PubMed

    Burton, Joe; Eggleston, Barry; Brenner, Jeffrey; Truchil, Aaron; Zulkiewicz, Brittany A; Lewis, Megan A

    2016-06-07

    Stakeholders often expect programs for persons with chronic conditions to "bend the cost curve." This study assessed whether a diabetes self-management education (DSME) program offered as part of a multicomponent initiative could affect emergency department (ED) visits, hospital stays, and the associated costs for an underserved population in addition to the clinical indicators that DSME programs attempt to improve. The program was implemented in Camden, New Jersey, by the Camden Coalition of Healthcare Providers to address disparities in diabetes care. Data used are from medical records and from patient-level information about hospital services from Camden's hospitals. Using multivariate regression models to control for individual characteristics, changes in utilization over time and changes relative to 2 comparison groups were assessed. No reductions in ED visits, inpatient stays, or costs for participants were found over time or relative to the comparison groups. High utilization rates and costs for diabetes are associated with longer term disease progression and its sequelae; thus, DSME or peer support may not affect these in the near term. Some clinical indicators improved among participants, and these might lead to fewer costly adverse health events in the future. DSME deployed at the community level, without explicit segmentation and targeting of high health care utilizers or without components designed to affect costs and utilization, should not be expected to reduce short-term medical needs for participating individuals or care-seeking behaviors such that utilization is reduced. Stakeholders must include financial outcomes in a program's design if those outcomes are to improve. (Population Health Management 20XX;XX:XXX-XXX).

  17. Broken Plane Delta-v Calculation For Rapid Assessment of Synthetic Asteroid Targets for In-situ Resource Utilization

    NASA Astrophysics Data System (ADS)

    Jedicke, Robert; Sercel, Joel; Morenz, Karen J.; Gertsch, Leslie S.

    2017-06-01

    We have developed a simplified mission model to estimate the quantity of deliverable water from small NEOs to distant retrograde lunar orbit (DRLO) as a function of Earth-return trip time and Δv. Our model is designed to be analytically simple, computationally efficient, and close enough to optimal to provide a realistic but conservative assessment of the relevant parameters. The challenge stems from the fact that we are not considering a mission to a specific, known target, but rather missions to the ensemble of NEOs in a synthetic population. To further simplify the analysis we treat Earth's heliocentric orbit as circular with a semi-major axis of 1 au and zero inclination.

  18. Mechanical properties, chemical analysis and evaluation of antimicrobial response of Si-DLC coatings fabricated on AISI 316 LVM substrate by a multi-target DC-RF magnetron sputtering method for potential biomedical applications

    NASA Astrophysics Data System (ADS)

    Bociaga, Dorota; Sobczyk-Guzenda, Anna; Szymanski, Witold; Jedrzejczak, Anna; Jastrzebska, Aleksandra; Olejnik, Anna; Jastrzebski, Krzysztof

    2017-09-01

    In this study silicon doped diamond-like carbon (Si-DLC) coatings were synthesized on two substrates: silicon and AISI 316LVM stainless steel using a multi-target DC-RF magnetron sputtering method. The Si content in the films ranged between 4 and 16 at.%, and was controlled by the electrical power applied in RF regime to Si cathode target. The character of the chemical bonds was revealed by FTIR analysis. With the addition of silicon the hydroxyl absorption (band in the range of 3200-3600 cm-1) increased what suggests more hydrophilic character of the coating. There were also observed significant changes in bonding of Si atoms. For low content of dopant, Si-O-Si bond system is predominant, while for the highest content of silicon there is an evidence of the shift to Si-C bonds in close proximity to methyl groups. The Raman spectroscopy revealed that the G peak position is shifted to a lower wavenumber and the ID/IG ratio decreased with increasing Si content, which indicates an increase in the C-sp3 content. Regardless of the coatings' composition, the improvement of hardness in comparison to pure substrate material (AISI 316 LVM) was observed. Although the reduction of the level of hardness from the level of 10.8 GPa for pure DLC to about 9.4 GPa for the silicon doped coatings was observed, the concomitant improvement of films adhesion with higher amount of Si was revealed. Although incorporation of the dopant to DLC coatings increases the number of E. coli cells which adhered to the examined surfaces, the microbial colonisation remains on the level of substrate material. The presented results prove the potential of Si-DLC coatings in biomedical applications from the point of view of their mechanical properties.

  19. Near-Earth Objects: Targets for Future Human Exploration, Solar System Science, Resource Utilization, and Planetary Defense

    NASA Technical Reports Server (NTRS)

    Abell, Paul A.

    2011-01-01

    U.S. President Obama stated on April 15, 2010 that the next goal for human spaceflight will be to send human beings to a near-Earth asteroid by 2025. Given this direction from the White House, NASA has been involved in studying various strategies for near-Earth object (NEO) exploration in order to follow U.S. Space Exploration Policy. This mission would be the first human expedition to an interplanetary body beyond the Earth-Moon system and would prove useful for testing technologies required for human missions to Mars and other Solar System destinations. Missions to NEOs would undoubtedly provide a great deal of technical and engineering data on spacecraft operations for future human space exploration while conducting in-depth scientific investigations of these primitive objects. In addition, the resulting scientific investigations would refine designs for future extraterrestrial resource extraction and utilization, and assist in the development of hazard mitigation techniques for planetary defense. This presentation will discuss some of the physical characteristics of NEOs and review some of the current plans for NEO research and exploration from both a human and robotic mission perspective.

  20. Novel viral vectors utilizing intron splice-switching to activate genome rescue, expression and replication in targeted cells

    PubMed Central

    2011-01-01

    Background The outcome of virus infection depends from the precise coordination of viral gene expression and genome replication. The ability to control and regulate these processes is therefore important for analysis of infection process. Viruses are also useful tools in bio- and gene technology; they can efficiently kill cancer cells and trigger immune responses to tumors. However, the methods for constructing tissue- or cell-type specific viruses typically suffer from low target-cell specificity and a high risk of reversion. Therefore novel and universal methods of regulation of viral infection are also important for therapeutic application of virus-based systems. Methods Aberrantly spliced introns were introduced into crucial gene-expression units of adenovirus vector and alphavirus DNA/RNA layered vectors and their effects on the viral gene expression, replication and/or the release of infectious genomes were studied in cell culture. Transfection of the cells with splice-switching oligonucleotides was used to correct the introduced functional defect(s). Results It was demonstrated that viral gene expression, replication and/or the release of infectious genomes can be blocked by the introduction of aberrantly spliced introns. The insertion of such an intron into an adenovirus vector reduced the expression of the targeted gene more than fifty-fold. A similar insertion into an alphavirus DNA/RNA layered vector had a less dramatic effect; here, only the release of the infectious transcript was suppressed but not the subsequent replication and spread of the virus. However the insertion of two aberrantly spliced introns resulted in an over one hundred-fold reduction in the infectivity of the DNA/RNA layered vector. Furthermore, in both systems the observed effects could be reverted by the delivery of splice-switching oligonucleotide(s), which corrected the splicing defects. Conclusions Splice-switch technology, originally developed for genetic disease therapy, can

  1. Utilizing hydrogen sulfide as a novel anti-cancer agent by targeting cancer glycolysis and pH imbalance

    PubMed Central

    Lee, Z-W; Teo, X-Y; Tay, E Y-W; Tan, C-H; Hagen, T; Moore, P K; Deng, L-W

    2014-01-01

    Background and Purpose Many disparate studies have reported the ambiguous role of hydrogen sulfide (H2S) in cell survival. The present study investigated the effect of H2S on the viability of cancer and non-cancer cells. Experimental Approach Cancer and non-cancer cells were exposed to H2S [using sodium hydrosulfide (NaHS) and GYY4137] and cell viability was examined by crystal violet assay. We then examined cancer cellular glycolysis by in vitro enzymatic assays and pH regulator activity. Lastly, intracellular pH (pHi) was determined by ratiometric pHi measurement using BCECF staining. Key Results Continuous, but not a single, exposure to H2S decreased cell survival more effectively in cancer cells, as compared to non-cancer cells. Slow H2S-releasing donor, GYY4137, significantly increased glycolysis, leading to overproduction of lactate. H2S also decreased anion exchanger and sodium/proton exchanger activity. The combination of increased metabolic acid production and defective pH regulation resulted in an uncontrolled intracellular acidification, leading to cancer cell death. In contrast, no significant intracellular acidification or cell death was observed in non-cancer cells. Conclusions and Implications Low and continuous exposure to H2S targets metabolic processes and pH homeostasis in cancer cells, potentially serving as a novel and selective anti-cancer strategy. PMID:24827113

  2. Production of RS4 from rice starch and its utilization as an encapsulating agent for targeted delivery of probiotics.

    PubMed

    Ashwar, Bilal Ahmad; Gani, Asir; Gani, Adil; Shah, Asima; Masoodi, Farooq Ahmad

    2018-01-15

    The research reported in this article is based on the hypothesis that crosslinking of starch can make it a potential wall material for targeted delivery of probiotics by altering its digestion. Three probiotic strains namely Lactobacillus casei, Lactobacillus brevis and Lactobacillus plantarum were microencapsulated with resistant starch. Encapsulation yield (%) of resistant starch microspheres was in the range of 43.01-48.46. The average diameter of resistant starch microparticles was in the range of 45.53-49.29μm. Fourier transform infrared (FT-IR) spectroscopy of microcapsules showed peaks in the region of 900-1300cm(-1) and 2918-2925cm(-1) which corresponds to the presence of bacteria. Differential Scanning Calorimeter (DSC) showed better thermal stability of resistant starch microcapsules. Microencapsulated probiotics survived well in simulated gastrointestinal conditions and adverse heat conditions. The viability of the microcapsulated lactobacilli also remained high (>7 log cfu g(-1)) for 2months at 4°C. The results revealed that resistant starch is the potential new delivery carrier for oral administration of probiotics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Impact of an acute coronary syndrome pathway in achieving target heart rate and utilization of evidence-based doses of beta-blockers.

    PubMed

    Irani, Farzan; Herial, Nabeel; Colyer, William R

    2012-11-01

    Beta-blockers remain a cornerstone of therapy in the management of acute coronary syndrome (ACS). The 2007 American College of Cardiology/American Heart Association unstable angina/non-ST elevation myocardial infarction guideline revisions recommend a target heart rate (HR) of 50-60 beats per minute (bpm). Despite improved trends toward utilization of beta-blockers therapy, beta-blockers continue to be underdosed. Guideline-based tools have been shown to improve adherence to evidence-based therapy in patients with ACS. Implementation of a standardized ACS pathway would lead to titration of beta-blockers to recommended dosages with improved HRs in eligible patients. The ACS clinical protocol was implemented at the University of Toledo Medical Center in May 2007. A retrospective study of 516 patients admitted during a comparable 6-month period, before and after the institution of the protocol, was conducted. The preprotocol and protocol group included 237 and 279 patients, respectively. Patient information extracted from the medical records included age, gender, HR on admission, blood pressure on admission, duration of hospital stay, preadmission use of beta-blocker, type of beta-blocker and dosage, discharge beta-blocker and dosage, peak troponin levels, and therapeutic intervention. A target HR of less than 60 bpm was achieved in 19% of the protocol group, as compared with 6% in the preprotocol group (P < 0.001). The protocol group had a significantly lower mean discharge HR than the preprotocol group (67 vs. 74 bpm; P < 0.001). The mean discharge dose of metoprolol in the protocol group was noted to be significantly higher (118 vs. 80 mg/d; P < 0.001). The institution of an ACS clinical pathway led to utilization of beta-blockers in significantly higher dosages, resulting in improved HR control and increased attainment of target HR.

  4. Enhanced k-edge angiography utilizing a superfluorescent x-ray generator with a gadolinium-target tube

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Germer, Rudolf; Obara, Haruo; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Inoue, Takashi; Ogawa, Akira; Sato, Shigehiro; Takayama, Kazuyoshi

    2007-01-01

    The gadolinium plasma flash x-ray generator is useful for performing high-speed enhanced K-edge angiography using cone beams because K-series characteristic x-rays from the gadolinium target are absorbed effectively by iodine-based contrast media. In the flash x-ray generator, a 150 nF condenser is charged up to 80 kV by a power supply, and flash x-rays are produced by the discharging. The x-ray tube is a demountable cold-cathode diode, and the turbomolecular pump evacuates air from the tube with a pressure of approximately 1 mPa. Since the electric circuit of the high-voltage pulse generator employs a cable transmission line, the high-voltage pulse generator produces twice the potential of the condenser charging voltage. At a charging voltage of 80 kV, the estimated maximum tube voltage and current are approximately 160 kV and 40 kA, respectively. When the charging voltage was increased, the K-series characteristic x-ray intensities of gadolinium increased. Bremsstrahlung x-ray intensity rate decreased with increasing the charging voltage, and clean K lines were produced with a charging voltage of 80 kV. The x-ray pulse widths were approximately 100 ns, and the time-integrated x-ray intensity had a value of approximately 500 μGy at 1.0 m from the x-ray source with a charging voltage of 80 kV. Angiography was performed using a filmless computed radiography (CR) system and iodine-based contrast media. In the angiography of nonliving animals, we observed fine blood vessels of approximately 100 μm with high contrasts.

  5. Cost-Utility of Stepped Care Targeting Psychological Distress in Patients With Head and Neck or Lung Cancer.

    PubMed

    Jansen, Femke; Krebber, Anna M H; Coupé, Veerle M H; Cuijpers, Pim; de Bree, Remco; Becker-Commissaris, Annemarie; Smit, Egbert F; van Straten, Annemieke; Eeckhout, Guus M; Beekman, Aartjan T F; Leemans, C René; Verdonck-de Leeuw, Irma M

    2017-01-20

    Purpose A stepped care (SC) program in which an effective yet least resource-intensive treatment is delivered to patients first and followed, when necessary, by more resource-intensive treatments was found to be effective in improving distress levels of patients with head and neck cancer or lung cancer. Information on the value of this program for its cost is now called for. Therefore, this study aimed to assess the cost-utility of the SC program compared with care-as-usual (CAU) in patients with head and neck cancer or lung cancer who have psychological distress. Patients and Methods In total, 156 patients were randomly assigned to SC or CAU. Intervention costs, direct medical costs, direct nonmedical costs, productivity losses, and health-related quality-of-life data during the intervention or control period and 12 months of follow-up were calculated by using Trimbos and Institute of Medical Technology Assessment Cost Questionnaire for Psychiatry, Productivity and Disease Questionnaire, and EuroQol-5 Dimension measures and data from the hospital information system. The SC program's value for the cost was investigated by comparing mean cumulative costs and quality-adjusted life years (QALYs). Results After imputation of missing data, mean cumulative costs were -€3,950 (95% CI, -€8,158 to -€190) lower, and mean number of QALYs was 0.116 (95% CI, 0.005 to 0.227) higher in the intervention group compared with the control group. The intervention group had a probability of 96% that cumulative QALYs were higher and cumulative costs were lower than in the control group. Four additional analyses were conducted to assess the robustness of this finding, and they found that the intervention group had a probability of 84% to 98% that cumulative QALYs were higher and a probability of 91% to 99% that costs were lower than in the control group. Conclusion SC is highly likely to be cost-effective; the number of QALYs was higher and cumulative costs were lower for SC

  6. Stepwise Molecular Display Utilizing Icosahedral and Helical Complexes of Phage Coat and Decoration Proteins in the Development of Robust Nanoscale Display Vehicles

    PubMed Central

    Parent, Kristin N.; Deedas, Christina T.; Egelman, Edward H.; Casjens, Sherwood R.; Baker, Timothy S.; Teschke, Carolyn M.

    2012-01-01

    A stepwise addition protocol was developed to display cargo using bacteriophage P22 capsids and the phage decorator (Dec) protein. Three-dimensional image reconstructions of frozen-hydrated samples of P22 particles with nanogold-labeled Dec bound to them revealed the locations of the N- and C- termini of Dec. Each terminus is readily accessible for molecular display through affinity tags such as nickel-nitrilotriacetic acid, providing a total of 240 cargo-binding sites. Dec was shown by circular dichroism to be a β–sheet rich protein, and fluorescence anisotropy binding experiments demonstrated that Dec binds to P22 heads with high (~110 nM) affinity. Dec also binds to P22 nanotubes, which are helically symmetric assemblies that form when the P22 coat protein contains the F170A amino acid substitution. Several classes of tubes with Dec bound to them were visualized by cryo-electron microscopy and their three-dimensional structures were determined by helical reconstruction methods. In all instances, Dec trimers bound to P22 capsids and nanotubes at positions where three neighboring capsomers (oligomers of six coat protein subunits) lie in close proximity to one another. Stable interactions between Dec and P22 allow for the development of robust, nanoscale size, display vehicles. PMID:22575828

  7. Synthesis, characterization, and biological verification of anti-HER2 indocyanine green-doxorubicin-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions for targeted photochemotherapy of breast cancer cells.

    PubMed

    Lee, Yu-Hsiang; Ma, Yun-Ting

    2017-05-18

    Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females worldwide. Among various types of breast cancer, the human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer is known to be more aggressive and often resistant to medicinal treatment, leading to an insufficient prognosis and poor susceptibility to chemotherapy and/or hormonal therapy in the current clinic. These circumstances implicate that developing an improved therapeutic strategy rather than persistently changing the anticancer drugs for trying is truly needed to successfully cure this type of breast cancer. In this study, we aimed to fabricate anti-HER2 indocyanine green (ICG)-doxorubicin (DOX)-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions (HIDPPDNEs) to explore the co-administration of phototherapy and chemotherapy for HER2-overexpressing breast cancer in vitro. The HIDPPDNE was first characterized as a sphere-like nanoparticle with surface charge of -57.1 ± 5.6 mV and size of 340.6 ± 4.5 nm, whereas the DOX release rates for the nanodroplets within 48 h in 4 and 37 °C were obtained by 8.13 ± 2.46% and 19.88 ± 2.75%, respectively. We then examined the target-ability of the nanostructure and found that the adhesion efficiency of the HIDPPDNEs onto HER2+ MDA-MB-453 cells was threefold higher than the nanodroplets without anti-HER2 antibody, indicating that the HIDPPDNEs are the product with HER2 binding specificity. In comparison to freely dissolved ICG, the HIDPPDNEs conferred an enhanced thermal stability to the entrapped ICG, and were able to provide a comparable hyperthermia effect and markedly increased production of singlet oxygen under near infrared irradiation (808 nm; 6 W/cm(2)). Based on the viability analyses, the results showed that the HIDPPDNEs were effective on cell eradication upon near infrared irradiation (808 nm; 6 W/cm(2)), and the resulting cell mortality was even higher

  8. COATED ALLOYS

    DOEpatents

    Harman, C.G.; O'Bannon, L.S.

    1958-07-15

    A coating is described for iron group metals and alloys, that is particularly suitable for use with nickel containing alloys. The coating is glassy in nature and consists of a mixture containing an alkali metal oxide, strontium oxide, and silicon oxide. When the glass coated nickel base metal is"fired'' at less than the melting point of the coating, it appears the nlckel diffuses into the vitreous coating, thus providing a closely adherent and protective cladding.

  9. Aluminide coatings

    DOEpatents

    Henager, Jr; Charles, H [Kennewick, WA; Shin, Yongsoon [Richland, WA; Samuels, William D [Richland, WA

    2009-08-18

    Disclosed herein are aluminide coatings. In one embodiment coatings are used as a barrier coating to protect a metal substrate, such as a steel or a superalloy, from various chemical environments, including oxidizing, reducing and/or sulfidizing conditions. In addition, the disclosed coatings can be used, for example, to prevent the substantial diffusion of various elements, such as chromium, at elevated service temperatures. Related methods for preparing protective coatings on metal substrates are also described.

  10. An improved Fc function assay utilizing CMV antigen-coated red blood cells generated with synthetic function-spacer-lipid constructs.

    PubMed

    Georgakopoulos, T; Komarraju, S; Henry, S; Bertolini, J

    2012-01-01

    The Fc function assessment of immunoglobulin products is performed to confirm that the biological activity of immunoglobulin products is not affected by manufacturing and storage conditions. The European Pharmacopoeia (EP) test is cumbersome and time-consuming especially with respect to the derivatization of red blood cells (RBC) with rubella antigen via tanninization. We investigated the KODE biosurface engineering technology for inserting specific antigens into red blood cell membranes to create kodecytes and evaluated their suitability for use in the Fc function assay. Human RBC were derivatized with function-spacer-lipid (FSL) constructs comprising of a peptide epitope of a cytomegalovirus (CMV) surface protein, conjugated to a spacer and lipid tail. These kodecytes were used in an Fc function assay based on the monitoring of complement-mediated haemolysis of immunoglobulin-coated red cells. Optimization of FSL construct, immunoglobulin and complement concentration was undertaken. Fc values obtained for various immunoglobulin batches were compared with those from the EP-based method. Carbohydrate-bearing FSLs Galili (Galα1-3Galβ1-4GlcNAcβ), Galα1-4GlcNAcβ and GalNAcα1-3Galβ were also evaluated. Fc function indices determined with CMV peptide construct-coated red cells were comparable to those obtained with the EP-based method with respect to specificity and precision. Carbohydrate-bearing FSLs revealed Fc indices lower than expected. The use of CMV kodecytes was shown to be a convenient means of generating red cells for the determination of Fc function of immunoglobulin products and offers the possibility of significantly reducing the time required to perform this assay. © 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.

  11. Construction of three-dimensional dermo-epidermal skin equivalents using cell coating technology and their utilization as alternative skin for permeation studies and skin irritation tests.

    PubMed

    Akagi, Takami; Nagura, Mayuka; Hiura, Ayami; Kojima, Hajime; Akashi, Mitsuru

    2017-03-23

    In vitro generated human skin equivalents are generating interest as promising tools in basic research, as alternatives to animal testing and for clinical applications in regenerative medicine. For prediction of skin irritation and corrosion, three-dimensional (3D) human skin equivalents consisting of differentiated human keratinocytes have been developed and some models have been internationally accepted. However, more delicate assessments using full-thickness skin models, such as skin sensitization tests cannot be performed because of the lack of a dermis containing fibroblasts or appendages. In a previous study, we developed dermo-epidermal human skin equivalents (DESEs) using a cell coating technique, which employs cell surface coating by layer-by-layer (LbL) assembled extracellular matrix (ECM) films. The DESEs with dermis consisting of normal human dermal fibroblasts (NHDF) and epidermis consisting of human keratinocytes (KC) were easily fabricated by using this technology. In this study, the constructed DESEs were evaluated as an alternative skin for skin permeation and irritation tests. A good relationship of permeability coefficient of chemicals was observed between the DESEs and human skin data. We investigated whether the DESEs, a new in vitro skin model, are able to identify skin irritant and non-irritant substances among 20 reference chemicals. It was confirmed that the DESEs are applicable to skin irritation testing as defined in the European Centre for the Validation of Alternative Methods (ECVAM) Performance Standard (OECD Test Guideline 439). We further studied the construction of the DESEs with density-controlled blood capillary networks using human umbilical vein endothelial cells (HUVEC). The results suggest that DESEs allowing incorporation of skin appendages are more promising alternatives to animal testing, and can be applied to the design of physiologically relevant in vitro skin models.

  12. Synthesis of dual-functional targeting probes for cancer theranostics based on iron oxide nanoparticles coated by centipede-like polymer connected with pH-responsive anticancer drug.

    PubMed

    Zhao, Haochen; Li, Zhiping; Yang, Bohan; Wang, Jingyuan; Li, Yapeng

    2015-01-01

    A tumor-targeted and pH-responsive drug release system based on superparamagnetic iron oxide nanoparticles (IONPs) coated by poly(ethylene glycol) (PEG) and dodecylamine (DDA)-modified polyitaconic acid (PIA) connecting with bortezomib (BTZ) (PIA-PEG-DDA-BTZ@IOs) has been constructed and characterized. The anticancer drug BTZ was first conjugated using dopamine as the linker via catechol borate ester bond, which is acid cleavable and used as an ideal pH-responsive drug release system. The IONPs were then coated by PIA-PEG-DDA-BTZ to form micelles with good biocompatibility. The conjugates were further designed to target liver cancer cells overexpressing vascular endothelial growth factor (VEGF) by the targeting molecule anti-vascular endothelial growth factor (anti-VEGF). The magnetic resonance imaging showed that the targeting capability of IONPs-anti-VEGF conjugates to Hep G2 cells was more significant than that of non-anti-VEGF IONPs. From the above, this kind of novel dual-functional targeting probe could provide a new idea for the diagnosis and treatment of cancer.

  13. BdCESA7, BdCESA8, and BdPMT Utility Promoter Constructs for Targeted Expression to Secondary Cell-Wall-Forming Cells of Grasses.

    PubMed

    Petrik, Deborah L; Cass, Cynthia L; Padmakshan, Dharshana; Foster, Cliff E; Vogel, John P; Karlen, Steven D; Ralph, John; Sedbrook, John C

    2016-01-01

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels in stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. The identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the BdCESA8 gene is

  14. BdCESA7, BdCESA8, and BdPMT Utility Promoter Constructs for Targeted Expression to Secondary Cell-Wall-Forming Cells of Grasses

    PubMed Central

    Petrik, Deborah L.; Cass, Cynthia L.; Padmakshan, Dharshana; Foster, Cliff E.; Vogel, John P.; Karlen, Steven D.; Ralph, John; Sedbrook, John C.

    2016-01-01

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels in stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. The identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the BdCESA8 gene is

  15. Safety and efficacy of low-dose paclitaxel utilizing the cobra-P drug-eluting stent system with a novel biodegradable coating in de novo coronary lesions: the PLUS-ONE first-in-man study.

    PubMed

    Calderas, Carlos; Condado, Jose Francisco; Condado, Jose Antonio; Flores, Alejandra; Mueller, Amy; Thomas, Jack; Nakatani, Daisaku; Honda, Yasuhiro; Waseda, Katsuhisa; Fitzgerald, Peter

    2014-01-01

    The Cobra-P drug-eluting stent (DES) system consists of cobalt chromium alloy with bio-absorbable siloxane sol-gel matrix coating that elutes low dose paclitaxel within 6 months. The aim of this first-in-man trial was to evaluate the safety and performance of 2 doses of the Cobra-P DES. A total of 60 lesions (54 patients) were sequentially assigned to 2 different paclitaxel doses: group A (3.7 μg/18mm, n=30) or group B (8 μg/18mm, n=30). The primary endpoint was MACE at 4 months defined as cardiac death, myocardial infarction, and target lesion revascularization. Patient and lesion characteristics were matched between the 2 groups except for male sex. MACE at 4 months was 3.3% and 0% respectively (P=1.000) and at 1-year follow-up remained unchanged. In-stent late loss at 4 months was similar in both groups (0.36 ± 0.30mm and 0.34 ± 0.20mm P=.773). In this FIM study, implantation of the Cobra-P low dose paclitaxel-eluting stent with a bioabsorbable sol-gel coating was proven to be feasible and safe. Moderate neointimal proliferation was observed as well as an acceptable MACE rate up to 1 year. © 2014.

  16. Preparation, characterization, and utilization of electrodes coated with polymeric networks formed by gamma-radiation crosslinking. Final report, 1 August 1982-31 January 1987

    SciTech Connect

    Heineman, W.R.; Mark, J.E.

    1987-04-01

    The preparation, characterization, and application of electrodes with specific chemical properties that are imparted by surface modification with polymer networks are the long-range goals of this research. Networks that are formed by crosslinking with gamma radiation were evaluated with respect to swelling in aqueous solution, retention of polymer in the network, permeability, and the effect of radiation dosage on all of these properties through its control of crosslinking. Ionic water-soluble polymers such as polydiallyl dimethyl ammonium cholride, poly vinylbenzyl trimethyl ammonium chloride, ploystyrene sulfonic acid, sodium salt and polyacrylic acid, which would ordinarily dissolve from the electrode surface in aqueous solution unless crosslinked into a network, and several neutral polymers such as polyacrylonitrile, polyethyleneimine, polydimethylsiloxane and poly vinyl alcohol investigated. The covalent attachment of organic and inorganic redox mediators and enzymes to networks by gamma irradiation of a mixture of polymer and the agent have been investigated. Network-coated electrodes with the appropriate properties are being developed for specific applications that required a stable, easily fabricated, fouling-resistant, rapidly responding, sensitive, and selective electrode.

  17. Synthesis, Characterization, and Biological Evaluation of Anti-HER2 Indocyanine Green-Encapsulated PEG-Coated PLGA Nanoparticles for Targeted Phototherapy of Breast Cancer Cells

    PubMed Central

    Lee, Yu-Hsiang; Lai, Yun-Han

    2016-01-01

    Human epidermal growth factor receptor 2 (HER2)-overexpressed breast cancer is known to be more aggressive and resistant to medicinal treatment and therefore to whom an alternative therapeutics is needed. Indocyanine green (ICG) has been widely exploited in breast cancer phototherapy. However, drawbacks of accelerated degradation and short half-life (2–4 min) in blood seriously hamper its use in the clinic. To overcome these challenges, an anti-HER2 ICG-encapsulated polyethylene glycol-coated poly(lactic-co-glycolic acid) nanoparticles (HIPPNPs) were developed in this study. Through the analyses of degradation rate coefficients of ICG with and without polymeric encapsulation, the photostability of HIPPNP-entrapped ICG significantly enhanced 4 folds (P < 0.05) while its thermal stabilities at 4 and 37°C significantly enhanced 5 and 3 (P < 0.05 for each) folds, respectively, under equal lighting and/or heating treatment for 48 h. The target specificity of HIPPNPs to HER2-positive cells was demonstrated based on a 6-fold (P < 0.05) enhancement of uptake efficiency of HIPPNPs in MDA-MB-453/HER2(+) cells within 4 h as compared with that in MCF7/HER2(-) cells. Moreover, the HIPPNPs with ≤ 25 μM ICG equivalent were nontoxic to cells in the absence of light illumination, and enabled to generate similar amount of singlet oxygen and hyperthermia effect as compared with that used by free ICG upon NIR irradiation. After 808 nm-laser irradiation with intensity of 6 W/cm2 for 5 min, the viability of MDA-MB-453 cells pre-treated by HIPPNPs with ≥ 5 μM ICG equivalent for 4 h significantly reduced as compared with that treated by equal concentration of free ICG (P < 0.05) and > 90% of the cells were eradicated while the dose of HIPPNPs was increased to 25 μM ICG equivalent. In summary, the developed HIPPNPs are anticipated as a feasible tool for use in phototherapy of breast cancer cells with HER2 expression. PMID:27942034

  18. Synthesis, Characterization, and Biological Evaluation of Anti-HER2 Indocyanine Green-Encapsulated PEG-Coated PLGA Nanoparticles for Targeted Phototherapy of Breast Cancer Cells.

    PubMed

    Lee, Yu-Hsiang; Lai, Yun-Han

    2016-01-01

    Human epidermal growth factor receptor 2 (HER2)-overexpressed breast cancer is known to be more aggressive and resistant to medicinal treatment and therefore to whom an alternative therapeutics is needed. Indocyanine green (ICG) has been widely exploited in breast cancer phototherapy. However, drawbacks of accelerated degradation and short half-life (2-4 min) in blood seriously hamper its use in the clinic. To overcome these challenges, an anti-HER2 ICG-encapsulated polyethylene glycol-coated poly(lactic-co-glycolic acid) nanoparticles (HIPPNPs) were developed in this study. Through the analyses of degradation rate coefficients of ICG with and without polymeric encapsulation, the photostability of HIPPNP-entrapped ICG significantly enhanced 4 folds (P < 0.05) while its thermal stabilities at 4 and 37°C significantly enhanced 5 and 3 (P < 0.05 for each) folds, respectively, under equal lighting and/or heating treatment for 48 h. The target specificity of HIPPNPs to HER2-positive cells was demonstrated based on a 6-fold (P < 0.05) enhancement of uptake efficiency of HIPPNPs in MDA-MB-453/HER2(+) cells within 4 h as compared with that in MCF7/HER2(-) cells. Moreover, the HIPPNPs with ≤ 25 μM ICG equivalent were nontoxic to cells in the absence of light illumination, and enabled to generate similar amount of singlet oxygen and hyperthermia effect as compared with that used by free ICG upon NIR irradiation. After 808 nm-laser irradiation with intensity of 6 W/cm2 for 5 min, the viability of MDA-MB-453 cells pre-treated by HIPPNPs with ≥ 5 μM ICG equivalent for 4 h significantly reduced as compared with that treated by equal concentration of free ICG (P < 0.05) and > 90% of the cells were eradicated while the dose of HIPPNPs was increased to 25 μM ICG equivalent. In summary, the developed HIPPNPs are anticipated as a feasible tool for use in phototherapy of breast cancer cells with HER2 expression.

  19. Target Organ Complications and Cardiovascular Events Associated With Masked Hypertension and White-Coat Hypertension: Analysis From the Dallas Heart Study.

    PubMed

    Tientcheu, Danielle; Ayers, Colby; Das, Sandeep R; McGuire, Darren K; de Lemos, James A; Khera, Amit; Kaplan, Norman; Victor, Ronald; Vongpatanasin, Wanpen

    2015-11-17

    Multiple epidemiological studies from Europe and Asia have demonstrated increased cardiovascular risks associated with isolated elevation of home blood pressure (BP) or masked hypertension (MH). Previous studies have not addressed cardiovascular outcomes associated with MH and white-coat hypertension (WCH) in the general population in the United States. The goal of this study was to determine hypertensive target organ damage and adverse cardiovascular outcomes associated with WCH (high clinic BP, ≥140/90 mm Hg; normal home BP, <135/85 mm Hg), MH (high home BP, ≥135/85 mm Hg; normal clinic BP, <140/90 mm Hg), and sustained hypertension (high home and clinic BP) in the DHS (Dallas Heart Study), a large, multiethnic, probability-based population cohort. Associations among WCH, MH, sustained hypertension, and aortic pulsed wave velocity by magnetic resonance imaging; urinary albumin-to-creatinine ratio; and cystatin C were evaluated at study baseline. Then, associations between WCH and MH with incident cardiovascular outcomes (coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death) over a median follow-up period of 9 years were assessed. The study cohort comprised 3,027 subjects (50% African Americans). The sample-weighted prevalence rates of WCH and MH were 3.3% and 17.8%, respectively. Both WCH and MH were independently associated with increased aortic pulsed wave velocity, cystatin C, and urinary albumin-to-creatinine ratio. Both WCH (adjusted hazard ratio: 2.09; 95% confidence interval: 1.05 to 4.15) and MH (adjusted hazard ratio: 2.03; 95% confidence interval: 1.36 to 3.03) were independently associated with higher cardiovascular events compared with the normotensive group, even after adjustment for traditional cardiovascular risk factors. In a multiethnic U.S. population, both WCH and MH were independently associated with increased aortic stiffness, renal injury, and incident cardiovascular events. Because MH is

  20. Active coatings technologies for tailorable military coating systems

    NASA Astrophysics Data System (ADS)

    Zunino, J. L., III

    2007-04-01

    The main objective of the U.S. Army's Active Coatings Technologies Program is to develop technologies that can be used in combination to tailor coatings for utilization on Army Materiel. The Active Coatings Technologies Program, ACT, is divided into several thrusts, including the Smart Coatings Materiel Program, Munitions Coatings Technologies, Active Sensor packages, Systems Health Monitoring, Novel Technology Development, as well as other advanced technologies. The goal of the ACT Program is to conduct research leading to the development of multiple coatings systems for use on various military platforms, incorporating unique properties such as self repair, selective removal, corrosion resistance, sensing, ability to modify coatings' physical properties, colorizing, and alerting logistics staff when tanks or weaponry require more extensive repair. A partnership between the U.S. Army Corrosion Office at Picatinny Arsenal, NJ along with researchers at the New Jersey Institute of Technology, NJ, Clemson University, SC, University of New Hampshire, NH, and University of Massachusetts (Lowell), MA, are developing the next generation of Smart Coatings Materiel via novel technologies such as nanotechnology, Micro-electromechanical Systems (MEMS), meta-materials, flexible electronics, electrochromics, electroluminescence, etc. This paper will provide the reader with an overview of the Active Coatings Technologies Program, including an update of the on-going Smart Coatings Materiel Program, its progress thus far, description of the prototype Smart Coatings Systems and research tasks as well as future nanotechnology concepts, and applications for the Department of Defense.

  1. Prospective blinded study of somatic mutation detection in cell-free DNA utilizing a targeted 54-gene next generation sequencing panel in metastatic solid tumor patients.

    PubMed

    Kim, Seung Tae; Lee, Won-Suk; Lanman, Richard B; Mortimer, Stefanie; Zill, Oliver A; Kim, Kyoung-Mee; Jang, Kee Taek; Kim, Seok-Hyung; Park, Se Hoon; Park, Joon Oh; Park, Young Suk; Lim, Ho Yeong; Eltoukhy, Helmy; Kang, Won Ki; Lee, Woo Yong; Kim, Hee-Cheol; Park, Keunchil; Lee, Jeeyun; Talasaz, AmirAli

    2015-11-24

    Sequencing of the mutant allele fraction of circulating cell-free DNA (cfDNA) derived from tumors is increasingly utilized to detect actionable genomic alterations in cancer. We conducted a prospective blinded study of a comprehensive cfDNA sequencing panel with 54 cancer genes. To evaluate the concordance between cfDNA and tumor DNA (tDNA), sequencing results were compared between cfDNA from plasma and genomic tumor DNA (tDNA). Utilizing next generation digital sequencing technology (DST), we profiled approximately 78,000 bases encoding 512 complete exons in the targeted genes in cfDNA from plasma. Seventy-five patients were prospectively enrolled between February 2013 and March 2014, including 61 metastatic cancer patients and 14 clinical stage II CRC patients with matched plasma and tissue samples. Using the 54-gene panel, we detected at least one somatic mutation in 44 of 61 tDNA (72.1%) and 29 of 44 (65.9%) cfDNA. The overall concordance rate of cfDNA to tDNA was 85.9%, when all detected mutations were considered. We collected serial cfDNAs during cetuximab-based treatment in 2 metastatic KRAS wild-type CRC patients, one with acquired resistance and one with primary resistance. We demonstrate newly emerged KRAS mutation in cfDNA 1.5 months before radiologic progression. Another patient had a newly emerged PIK3CA H1047R mutation on cfDNA analysis at progression during cetuximab/irinotecan chemotherapy with gradual increase in allele frequency from 0.8 to 2.1%. This blinded, prospective study of a cfDNA sequencing showed high concordance to tDNA suggesting that the DST approach may be used as a non-invasive biopsy-free alternative to conventional sequencing using tumor biopsy.

  2. Prospective blinded study of somatic mutation detection in cell-free DNA utilizing a targeted 54-gene next generation sequencing panel in metastatic solid tumor patients

    PubMed Central

    Lanman, Richard B.; Mortimer, Stefanie; Zill, Oliver A.; Kim, Kyoung-Mee; Jang, Kee Taek; Kim, Seok-Hyung; Park, Se Hoon; Park, Joon Oh; Park, Young Suk; Lim, Ho Yeong; Eltoukhy, Helmy; Kang, Won Ki; Lee, Woo Yong; Kim, Hee-Cheol; Park, Keunchil; Lee, Jeeyun; Talasaz, AmirAli

    2015-01-01

    Sequencing of the mutant allele fraction of circulating cell-free DNA (cfDNA) derived from tumors is increasingly utilized to detect actionable genomic alterations in cancer. We conducted a prospective blinded study of a comprehensive cfDNA sequencing panel with 54 cancer genes. To evaluate the concordance between cfDNA and tumor DNA (tDNA), sequencing results were compared between cfDNA from plasma and genomic tumor DNA (tDNA). Utilizing next generation digital sequencing technology (DST), we profiled approximately 78,000 bases encoding 512 complete exons in the targeted genes in cfDNA from plasma. Seventy-five patients were prospectively enrolled between February 2013 and March 2014, including 61 metastatic cancer patients and 14 clinical stage II CRC patients with matched plasma and tissue samples. Using the 54-gene panel, we detected at least one somatic mutation in 44 of 61 tDNA (72.1%) and 29 of 44 (65.9%) cfDNA. The overall concordance rate of cfDNA to tDNA was 85.9%, when all detected mutations were considered. We collected serial cfDNAs during cetuximab-based treatment in 2 metastatic KRAS wild-type CRC patients, one with acquired resistance and one with primary resistance. We demonstrate newly emerged KRAS mutation in cfDNA 1.5 months before radiologic progression. Another patient had a newly emerged PIK3CA H1047R mutation on cfDNA analysis at progression during cetuximab/irinotecan chemotherapy with gradual increase in allele frequency from 0.8 to 2.1%. This blinded, prospective study of a cfDNA sequencing showed high concordance to tDNA suggesting that the DST approach may be used as a non-invasive biopsy-free alternative to conventional sequencing using tumor biopsy. PMID:26452027

  3. BdCESA7, BdCESA8, and BdPMT utility promoter constructs for targeted expression to secondary cell-wall-forming cells of grasses

    DOE PAGES

    Petrik, Deborah L.; Cass, Cynthia L.; Padmakshan, Dharshana; ...

    2016-02-04

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels inmore » stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. Lastly, the identification, in Bdcesa8-1 T-DNA mutant stems, of an 80% reduction in crystalline cellulose levels confirms that the

  4. Degradative capacities and 16S rRNA-targeted whole-cell hybridization of sulfate-reducing bacteria in an anaerobic enrichment culture utilizing alkylbenzenes from crude oil.

    PubMed Central

    Rabus, R; Fukui, M; Wilkes, H; Widdle, F

    1996-01-01

    A mesophilic sulfate-reducing enrichment culture growing anaerobically on crude oil was used as a model system to study which nutritional types of sulfate-reducing bacteria may develop on original petroleum constituents in oil wells, tanks, and pipelines. Chemical analysis of oil hydrocarbons during growth revealed depletion of toluene and o-xylene within 1 month and of m-xylene, o-ethyltoluene, m-ethyltoluene, m-propyltoluene, and m-isopropyltoluene within approximately 2 months. In anaerobic counting series, the highest numbers of CFU (6 x 10(6) to 8 x 10(6) CFU ml-1) were obtained with toluene and benzoate. Almost the same numbers were obtained with lactate, a substrate often used for detection of the vibrio-shaped, incompletely oxidizing Desulfovibrio sp. In the present study, however, lactate yielded mostly colonies of oval to rod-shaped, completely oxidizing, sulfate-reducing bacteria which were able to grow slowly on toluene or crude oil. Desulfovibrio species were detected only at low numbers (3 x 10(5) CFU ml-1). In agreement with this finding, a fluorescently labeled, 16S rRNA-targeted oligonucleotide probe described in the literature as specific for members of the Desulfovibrionaceae (suggested family) hybridized only with a small portion (< 5%) of the cells in the enrichment culture. These results are consistent with the observation that known Desulfovibrio species do not utilize aromatic hydrocarbons, the predominant substrates in the enrichment culture. All known sulfate-reducing bacteria which utilize aromatic compounds belong to a separate branch, the Desulfobacteriaceae (suggested family). Most members of this family are complete oxidizers. For specific hybridization with members of this branch, the probe had to be modified by a nucleotide exchange. Indeed, this modified probe hybridized with more than 95% of the cells in the enrichment culture. The results show that completely oxidizing, alkylbenzene-utilizing sulfate-reducing bacteria rather than

  5. Metal Coatings

    NASA Technical Reports Server (NTRS)

    1994-01-01

    During the Apollo Program, General Magnaplate Corporation developed process techniques for bonding dry lubricant coatings to space metals. The coatings were not susceptible to outgassing and offered enhanced surface hardness and superior resistance to corrosion and wear. This development was necessary because conventional lubrication processes were inadequate for lightweight materials used in Apollo components. General Magnaplate built on the original technology and became a leader in development of high performance metallurgical surface enhancement coatings - "synergistic" coatings, - which are used in applications from pizza making to laser manufacture. Each of the coatings is designed to protect a specific metal or group of metals to solve problems encountered under operating conditions.

  6. Surface-enhanced raman scattering detection of DNAs derived from virus genomes using au-coated paramagnetic nanoparticles

    USDA-ARS?s Scientific Manuscript database

    A magnetic capture-based, surface-enhanced Raman scattering (SERS) assay for DNA detection has been developed which utilizes Au-coated paramagnetic nanoparticles (Au@PMPs) as both a SERS substrate and effective bio-separation reagent for the selective removal of target DNAs from solution. Hybridizat...

  7. A wheat intervarietal genetic linkage map based on microsatellite and target region amplified polymorphism markers and its utility for detecting quantitative trait loci.

    PubMed

    Liu, Z H; Anderson, J A; Hu, J; Friesen, T L; Rasmussen, J B; Faris, J D

    2005-08-01

    Efficient user-friendly methods for mapping plant genomes are highly desirable for the identification of quantitative trait loci (QTLs), genotypic profiling, genomic studies, and marker-assisted selection. SSR (microsatellite) markers are user-friendly and efficient in detecting polymorphism, but they detect few loci. Target region amplification polymorphism (TRAP) is a relatively new PCR-based technique that detects a large number of loci from a single reaction without extensive pre-PCR processing of samples. In the investigation reported here, we used both SSRs and TRAPs to generate over 700 markers for the construction of a genetic linkage map in a hard red spring wheat intervarietal recombinant inbred population. A framework map consisting of 352 markers accounted for 3,045 cM with an average density of one marker per 8.7 cM. On average, SSRs detected 1.9 polymorphic loci per reaction, while TRAPs detected 24. Both marker systems were suitable for assigning linkage groups to chromosomes using wheat aneuploid stocks. We demonstrated the utility of the maps by identifying major QTLs for days to heading and reduced plant height on chromosomes 5A and 4B, respectively. Our results indicate that TRAPs are highly efficient for genetic mapping in wheat. The maps developed will be useful for the identification of quality and disease resistance QTLs that segregate in this population.

  8. A Review: The Current In Vivo Models for the Discovery and Utility of New Anti-leishmanial Drugs Targeting Cutaneous Leishmaniasis

    PubMed Central

    Mears, Emily Rose; Modabber, Farrokh; Don, Robert; Johnson, George E.

    2015-01-01

    The current in vivo models for the utility and discovery of new potential anti-leishmanial drugs targeting Cutaneous Leishmaniasis (CL) differ vastly in their immunological responses to the disease and clinical presentation of symptoms. Animal models that show similarities to the human form of CL after infection with Leishmania should be more representative as to the effect of the parasite within a human. Thus, these models are used to evaluate the efficacy of new anti-leishmanial compounds before human clinical trials. Current animal models aim to investigate (i) host–parasite interactions, (ii) pathogenesis, (iii) biochemical changes/pathways, (iv) in vivo maintenance of parasites, and (v) clinical evaluation of drug candidates. This review focuses on the trends of infection observed between Leishmania parasites, the predictability of different strains, and the determination of parasite load. These factors were used to investigate the overall effectiveness of the current animal models. The main aim was to assess the efficacy and limitations of the various CL models and their potential for drug discovery and evaluation. In conclusion, we found that the following models are the most suitable for the assessment of anti-leishmanial drugs: L. major–C57BL/6 mice (or–vervet monkey, or–rhesus monkeys), L. tropica–CsS-16 mice, L. amazonensis–CBA mice, L. braziliensis–golden hamster (or–rhesus monkey). We also provide in-depth guidance for which models are not suitable for these investigations. PMID:26334763

  9. Low Conductivity Thermal Barrier Coatings

    NASA Technical Reports Server (NTRS)

    Zhu, Dong-Ming

    2005-01-01

    Thermal barrier coatings will be more aggressively designed to protect gas turbine engine hot-section components in order to meet future engine higher fuel efficiency and lower emission goals. In this presentation, thermal barrier coating development considerations and requirements will be discussed. An experimental approach is established to monitor in real time the thermal conductivity of the coating systems subjected to high-heat-flux, steady-state and cyclic temperature gradients. Advanced low conductivity thermal barrier coatings have also been developed using a multi-component defect clustering approach, and shown to have improved thermal stability. The durability and erosion resistance of low conductivity thermal barrier coatings have been improved utilizing advanced coating architecture design, composition optimization, in conjunction with more sophisticated modeling and design tools.

  10. Investigation of terahertz waves propagating through far infrared/CO2 laser stealth-compatible coating based on one-dimensional photonic crystal

    NASA Astrophysics Data System (ADS)

    Wang, Qichao; Wang, Jiachun; Zhao, Dapeng; Zhang, Jikui; Li, Zhigang; Chen, Zongsheng; Zeng, Jie; Miao, Lei; Shi, Jiaming

    2016-11-01

    We propose a new method to disclose the camouflaged targets coated with far infrared/CO2 laser stealth-compatible coating by utilizing terahertz (THz) radar. A coating based on one-dimensional photonic crystal (1DPC) with a defect mode is specially designed and successfully prepared, which possesses a high reflectivity in 8-14 μm waveband and a low reflectivity at 10.6 μm, by alternating thin films of Ge, ZnSe and Si. The propagation characteristic of 0.3-2 THz wave at incident angle from 0° to 80° in such PC coating is investigated theoretically based on characteristic matrix method. The maximal transmittance is up to 92%, and the absorptivity keeps lower than 0.5% over the whole band. The results are verified by experiments, which demonstrate the feasibility of using THz radar to detect the targets covered with such stealth-compatible coatings.

  11. Utilization of interfacial engineering to improve physicochemical stability of β-carotene emulsions: Multilayer coatings formed using protein and protein-polyphenol conjugates.

    PubMed

    Liu, Fuguo; Wang, Di; Sun, Cuixia; McClements, David Julian; Gao, Yanxiang

    2016-08-15

    The impact of lactoferrin (LF)-chlorogenic acid (CA) and (-)-Epigallocatechin-3-gallate (EGCG) conjugates on the physicochemical properties of β-carotene emulsions was investigated. Formation of lactoferrin-polyphenol conjugates, which was confirmed by SDS-PAGE, caused changes in the structure and nature of lactoferrin. Based on layer-by-layer electrostatic deposition, β-carotene bilayer emulsions were prepared by lactoferrin and lactoferrin-polyphenol conjugates at pH 7.0. The physicochemical properties of primary and secondary emulsions were evaluated and the results suggested that LF-polyphenol conjugates-stabilized primary and secondary emulsions exhibited better emulsifying properties and improved physical stability of β-carotene bilayer emulsions under freeze-thaw, ionic strength and thermal treatments. In addition, the lactoferrin-polyphenol conjugates could effectively enhance chemical stability of β-carotene in oil-in-water emulsions against heat treatment and ultraviolet light exposure, and the least degradation of β-carotene occurred in LF-EGCG conjugate-stabilized primary emulsion. The interfacial engineering technology utilized in this study may lead to the formation of emulsions with improved physicochemical and functional performance.

  12. Smart pH- and reduction-dual-responsive folate-PEG-coated polymeric lipid vesicles for tumor-triggered targeted drug delivery

    NASA Astrophysics Data System (ADS)

    Wang, Sheng; Wang, Hanjie; Liu, Zhongyun; Wang, Liangliang; Wang, Xiaomin; Su, Lin; Chang, Jin

    2014-06-01

    To improve their therapeutic index, designed nanocarriers should preferentially accumulate in tumor tissues and then rapidly enter tumor cells to release the encapsulated drugs in a triggered manner. In this article, a new kind of a smart pH- and reduction-dual-responsive drug delivery system based on folate-PEG-coated polymeric lipid vesicles (FPPLVs) formed from amphiphilic dextran derivatives was designed and prepared successfully. PEG chains with pH-sensitive hydrazone bonds, stearyl alcohol (SA) chains with reduction-sensitive disulfide bonds and folate were connected to a dextran main chain. The newly developed FPPLVs had a nano-sized structure (~50 nm) with a PEG coating. The in vitro DOX release profiles showed that the FPPLVs achieved a triggered drug release in response to acidic pH and reducing environments due to the cleavage of hydrazone bonds and disulfide bonds. It has also been demonstrated by an in vitro cellular uptake study that the FPPLVs lose their PEG coating as well as expose the folate in acidic conditions, which allows them to efficiently enter tumor cells through ligand-receptor interactions. In vitro cytotoxicity measurements also confirmed that FPPLVs exhibited pronounced antitumor activity against HeLa cells. These results suggest that FPPLVs are promising carriers for smart antitumor drug delivery applications.To improve their therapeutic index, designed nanocarriers should preferentially accumulate in tumor tissues and then rapidly enter tumor cells to release the encapsulated drugs in a triggered manner. In this article, a new kind of a smart pH- and reduction-dual-responsive drug delivery system based on folate-PEG-coated polymeric lipid vesicles (FPPLVs) formed from amphiphilic dextran derivatives was designed and prepared successfully. PEG chains with pH-sensitive hydrazone bonds, stearyl alcohol (SA) chains with reduction-sensitive disulfide bonds and folate were connected to a dextran main chain. The newly developed FPPLVs had a

  13. Templated biomimetic multifunctional coatings

    NASA Astrophysics Data System (ADS)

    Sun, Chih-Hung; Gonzalez, Adriel; Linn, Nicholas C.; Jiang, Peng; Jiang, Bin

    2008-02-01

    We report a bioinspired templating technique for fabricating multifunctional optical coatings that mimic both unique functionalities of antireflective moth eyes and superhydrophobic cicada wings. Subwavelength-structured fluoropolymer nipple arrays are created by a soft-lithography-like process. The utilization of fluoropolymers simultaneously enhances the antireflective performance and the hydrophobicity of the replicated films. The specular reflectivity matches the optical simulation using a thin-film multilayer model. The dependence of the size and the crystalline ordering of the replicated nipples on the resulting antireflective properties have also been investigated by experiment and modeling. These biomimetic materials may find important technological application in self-cleaning antireflection coatings.

  14. Thermal barrier coatings: A near term, high payoff technology

    NASA Technical Reports Server (NTRS)

    Levine, S. R.; Clark, J. S.

    1977-01-01

    The present status of thermal barrier coatings is reviewed including both experimental results and forecasts of the benefits derived from use of these coatings in aircraft and utility gas turbines. The potential of thermal barrier coatings relative to structural ceramics is discussed along with a development plan for these coatings.

  15. Coated foams, preparation, uses and articles

    DOEpatents

    Duchane, D.V.; Barthell, B.L.

    1982-10-21

    Hydrophobic cellular material is coated with a thin hydrophilic polymer skin which stretches tightly over the foam but which does not fill the cells of the foam, thus resulting in a polymer-coated foam structure having a smoothness which was not possible in the prior art. In particular, when the hydrophobic cellular material is a specially chosen hydrophobic polymer foam and is formed into arbitrarily chosen shapes prior to the coating with hydrophilic polymer, inertial confinement fusion (ICF) targets of arbitrary shapes can be produced by subsequently coating the shapes with metal or with any other suitable material. New articles of manufacture are produced, including improved ICF targets, improved integrated circuits, and improved solar reflectors and solar collectors. In the coating method, the cell size of the hydrophobic cellular material, the viscosity of the polymer solution used to coat, and the surface tension of the polymer solution used to coat are all very important to the coating.

  16. Thermal barrier coating life prediction model

    NASA Technical Reports Server (NTRS)

    Hillery, R. V.; Pilsner, B. H.

    1985-01-01

    This is the first report of the first phase of a 3-year program. Its objectives are to determine the predominant modes of degradation of a plasma sprayed thermal barrier coating system, then to develop and verify life prediction models accounting for these degradation modes. The first task (Task I) is to determine the major failure mechanisms. Presently, bond coat oxidation and bond coat creep are being evaluated as potential TBC failure mechanisms. The baseline TBC system consists of an air plasma sprayed ZrO2-Y2O3 top coat, a low pressure plasma sprayed NiCrAlY bond coat, and a Rene'80 substrate. Pre-exposures in air and argon combined with thermal cycle tests in air and argon are being utilized to evaluate bond coat oxidation as a failure mechanism. Unexpectedly, the specimens pre-exposed in argon failed before the specimens pre-exposed in air in subsequent thermal cycles testing in air. Four bond coats with different creep strengths are being utilized to evaluate the effect of bond coat creep on TBC degradation. These bond coats received an aluminide overcoat prior to application of the top coat to reduce the differences in bond coat oxidation behavior. Thermal cycle testing has been initiated. Methods have been selected for measuring tensile strength, Poisson's ratio, dynamic modulus and coefficient of thermal expansion both of the bond coat and top coat layers.

  17. Rapid at-line analysis of coating thickness and uniformity on tablets using laser induced breakdown spectroscopy.

    PubMed

    Mowery, Mark D; Sing, Robert; Kirsch, John; Razaghi, Amir; Béchard, Simon; Reed, Robert A

    2002-06-01

    Because of the functionality of controlled release tablet coatings, it is desirable to have a rapid means of optimizing coating conditions and predicting the performance of a batch at-line, prior to exhaustive lab analysis. In this paper, Laser Induced Breakdown Spectroscopy (LIBS) was utilized for the first time as a rapid means of simultaneously determining the thickness and uniformity of an enteric coating on compressed tablets. In these studies, the core tablets contained a high concentration of calcium, and the coating contained titanium, silicon, and magnesium, all of which are excellent analytical targets for LIBS. The emission spectra of all four elements were simultaneously monitored as a function of the number of laser pulses in the same spatial location, literally drilling through the coating and into the core tablet. The depth penetration of individual laser pulses was calibrated using profilometry, and the thickness of the coating was determined by the incidence of calcium signal and simultaneous decrease in emission from the other probe elements (titanium, silicon and magnesium) as the laser penetrated the coating. Coating thickness measurements were evaluated by sampling coatings ranging from 5 to 21% (100 mg tablet weight basis). Additionally, LIBS spatial resolution capabilities were exploited to evaluate the film coat thickness uniformity across the tablet faces and edges. Furthermore, tablet to tablet uniformity differences were readily assessable. The results indicate that a change in coating application of less than 2 wt.% on a 100 mg tablet can be easily detected. The rapid analysis times for this technique (10 tablets were analyzed in under 15 min) makes it applicable for in-process evaluation of coating thickness, as well as intra- and inter-tablet coating uniformity on compressed tablets.

  18. Solar Absorptance of Cermet Coatings Evaluated

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.

    2004-01-01

    Cermet coatings, molecular mixtures of metal and ceramic, are being considered for the heat inlet surface of solar Stirling convertors. In this application, the key role of the cermet coating is to absorb as much of the incident solar energy as possible. To achieve this objective, the cermet coating has a high solar absorptance value. Cermet coatings are manufactured utilizing sputter deposition, and many different metal and ceramic combinations can be created. The ability to mix metal and ceramic at the atomic level offers the opportunity to tailor the composition, and hence, the optical properties of these coatings. The NASA Glenn Research Center has prepared and characterized a wide variety of cermet coatings utilizing different metals deposited in an aluminum oxide ceramic matrix. In addition, the atomic oxygen durability of these coatings has been evaluated.

  19. Evaluation of poly(3,4-ethylenedioxythiophene)/carbon nanotube neural electrode coatings for stimulation in the dorsal root ganglion

    PubMed Central

    Kolarcik, Christi L.; Catt, Kasey; Rost, Erika; Albrecht, Ingrid N.; Bourbeau, Dennis; Du, Zhanhong; Kozai, Takashi D.Y.; Luo, Xiliang; Weber, Douglas J.; Cui, X. Tracy

    2015-01-01

    Objective The dorsal root ganglion (DRG) is an attractive target for implanting neural electrode arrays that restore sensory function or provide therapy via stimulation. However, penetrating microelectrodes designed for these applications are small and deliver low currents. For long-term performance of microstimulation devices, novel coating materials are needed in part to decrease impedance values at the electrode-tissue interface and to increase charge storage capacity. Approach Conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and multiwall carbon nanotubes (CNTs) were coated on the electrode surface and doped with the anti-inflammatory drug, dexamethasone. Electrode characteristics and the tissue reaction around neural electrodes as the result of stimulation, coating and drug release were characterized. Hematoxylin and eosin staining along with antibodies recognizing Iba1 (microglia/macrophages), NF200 (neuronal axons), NeuN (neurons), vimentin (fibroblasts), caspase-3 (cell death) and L1 (neural cell adhesion molecule) were used. Quantitative image analyses were performed using MATLAB. Main Results Our results indicate that coated microelectrodes have lower in vitro and in vivo impedance values. Significantly less neuronal death/damage was observed with coated electrodes as compared to non-coated controls. The inflammatory response with the PEDOT/CNT-coated electrodes was also reduced. Significance This study is the first to report on the utility of these coatings in stimulation applications. Our results indicate PEDOT/CNT coatings may be valuable additions to implantable electrodes used as therapeutic modalities. PMID:25485675

  20. Evaluation of poly(3,4-ethylenedioxythiophene)/carbon nanotube neural electrode coatings for stimulation in the dorsal root ganglion

    NASA Astrophysics Data System (ADS)

    Kolarcik, Christi L.; Catt, Kasey; Rost, Erika; Albrecht, Ingrid N.; Bourbeau, Dennis; Du, Zhanhong; Kozai, Takashi D. Y.; Luo, Xiliang; Weber, Douglas J.; Cui, X. Tracy

    2015-02-01

    Objective. The dorsal root ganglion is an attractive target for implanting neural electrode arrays that restore sensory function or provide therapy via stimulation. However, penetrating microelectrodes designed for these applications are small and deliver low currents. For long-term performance of microstimulation devices, novel coating materials are needed in part to decrease impedance values at the electrode-tissue interface and to increase charge storage capacity. Approach. Conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-wall carbon nanotubes (CNTs) were coated on the electrode surface and doped with the anti-inflammatory drug, dexamethasone. Electrode characteristics and the tissue reaction around neural electrodes as a result of stimulation, coating and drug release were characterized. Hematoxylin and eosin staining along with antibodies recognizing Iba1 (microglia/macrophages), NF200 (neuronal axons), NeuN (neurons), vimentin (fibroblasts), caspase-3 (cell death) and L1 (neural cell adhesion molecule) were used. Quantitative image analyses were performed using MATLAB. Main results. Our results indicate that coated microelectrodes have lower in vitro and in vivo impedance values. Significantly less neuronal death/damage was observed with coated electrodes as compared to non-coated controls. The inflammatory response with the PEDOT/CNT-coated electrodes was also reduced. Significance. This study is the first to report on the utility of these coatings in stimulation applications. Our results indicate PEDOT/CNT coatings may be valuable additions to implantable electrodes used as therapeutic modalities.

  1. Hydroxyapatite coatings.

    PubMed

    Lacefield, W R

    1988-01-01

    Four coating techniques were evaluated to determine which is most suitable for producing a dense, highly adherent coating onto metallic and ceramic implant materials. Two of the selected coating methods have serious limitations for use in this particular application, and did not meet the specified criteria for satisfactory coating as defined in the initial stages of the study. For example, the dip coating-sintering technique was judged to be unsatisfactory because of the adverse effect of the high-temperature sintering cycle on the mechanical properties of the metallic substrate materials. These materials could not be used in load-bearing applications because of the excessive grain growth and loss of the wrought structure of both the commercially pure Ti and Ti-6Al-4V substrates, and the loss of ductility in the cast Co-Cr-Mo alloy. Another area of concern was that bond strength between the HA coating and the substrate was not high enough to insure that interfacial failure would not occur during the lifetime of the implant. The immersion-coating technique, in which the metal substrate is immersed into the molten ceramic, was shown in a previous study to be the best method of coating a bioreactive glass onto a Co-Cr-Mo implant. Heating HA above its melting temperature, however, caused undesired compositional and structural changes, and upon solidification very limited adherence between the modified ceramic and substrate material occurred under the conditions of this study. The HIP technique, in which the Ti powder substrate and the HA powder coating are sintered together in a high-pressure autoclave, shows great promise for the fabrication of high-quality composite implants. Initial studies have indicated that high-density Ti substrates with a small grain size that are well bonded to a dense HA coating can be produced under optimum conditions. Sintering and densification additives, such as SiO2 powder, do not appear to be necessary. The main drawback to this

  2. Protective coating for copper in aluminum heat exchangers

    NASA Technical Reports Server (NTRS)

    Avazian, R.

    1978-01-01

    Application of ultrathin layer of molybdenum disulfied coating to copper tubing permits utilization of tubing in cast-aluminum heat exchangers. Coating prevents formation of copper/aluminum eutectic, but does not impede heat transfer.

  3. Nanocluster of superparamagnetic iron oxide nanoparticles coated with poly (dopamine) for magnetic field-targeting, highly sensitive MRI and photothermal cancer therapy.

    PubMed

    Wu, Ming; Zhang, Da; Zeng, Yongyi; Wu, Lingjie; Liu, Xiaolong; Liu, Jingfeng

    2015-03-20

    In this paper, a core–shell nanocomposite of clusters of superparamagnetic iron oxide nanoparticles coated with poly(dopamine) (SPION clusters@PDA) is fabricated as a magnetic field-directed theranostic agent that combines the capabilities of highly sensitive magnetic resonance imaging (MRI) and photothermal cancer therapy. The highly concentrated SPION cluster core is suitable for sensitive MRI due to its superparamagnetic properties, and the poly(dopamine) coating layer can induce cancer cell death under near-infrared (NIR) laser irradiation because of the photothermal conversion ability of PDA. MRI scanning reveals that the nanocomposite has relatively high r2 and r2(*) relaxivities, and the r2(*) values are nearly threefold higher than the r2 values because of the clustering of the SPIONs in the nanocomposite core. Due to the rapid response to magnetic field gradients, enhanced cellular uptake of our nanocomposite mediated by an external magnetic field can be achieved, thus producing significantly enhanced local photothermal killing efficiency against cancer cells under NIR irritation.

  4. Silicone nanocomposite coatings for fabrics

    NASA Technical Reports Server (NTRS)

    Eberts, Kenneth (Inventor); Lee, Stein S. (Inventor); Singhal, Amit (Inventor); Ou, Runqing (Inventor)

    2011-01-01

    A silicone based coating for fabrics utilizing dual nanocomposite fillers providing enhanced mechanical and thermal properties to the silicone base. The first filler includes nanoclusters of polydimethylsiloxane (PDMS) and a metal oxide and a second filler of exfoliated clay nanoparticles. The coating is particularly suitable for inflatable fabrics used in several space, military, and consumer applications, including airbags, parachutes, rafts, boat sails, and inflatable shelters.

  5. Regulatory Aspects of Coatings

    USDA-ARS?s Scientific Manuscript database

    This chapter gives a history of the development and uses of edible coating regulations, detailed chapters on coating caracteristics, determination of coating properties, methods for making coatings, and discription of coating film formers (polysaccharieds, lipids, resins, proteins). The chapter also...

  6. Alternative RPC Coatings

    NASA Astrophysics Data System (ADS)

    Strack, Jason

    2009-10-01

    The nuclear physics group at the University of Illinois is currently developing techniques to further improve the performance of Bakelite Resistive Plate Chambers (RPCs) for use as muon trigger detectors in experiments at hadron colliders. Muon trigger RPCs at LHC and RHIC typically use Bakelite plates coated with linseed oil. Both Bakelite and linseed oil, however, have high bulk and surface resistivity thus limiting the detection efficiency of the RPC at high rates. Experiments which dope the linseed oil with either carbon or copper are carried out with the goal to select targeted lower surface resistivity values for the coating applied to the Bakelite plates. Two doping procedures have been studied. In the first method a thin layer of graphite is deposited between the Bakelite and the linseed oil. For the second method the graphite or copper powder are deposited on top of the drying linseed oil coating. In this presentation the coating methods will be discussed and the effects of the coating on the RPC position resolution, cluster size and efficiencies will be discussed.

  7. Human serum albumin supported lipid patterns for the targeted recognition of microspheres coated by membrane based on ss-DNA hybridization

    SciTech Connect

    Zhang Xiaoming; He Qiang; Duan Li; Li Junbai . E-mail: jbli@iccas.ac.cn

    2006-10-27

    Human serum albumin (HSA) patterns have been successfully fabricated for the deposition of lipid bilayer, 1,2-dimyristoyl-sglycerophosphate (DMPA), by making use of the micro-contact printing ({mu}CP) technique and liposome fusion. Confocal laser scanning microscopy (CLSM) results indicate that lipid bilayer has been assembled in HSA patterns with a good stability. Such well-defined lipid patterns formed on HSA surface create possibility to incorporate specific components like channels or receptors for specific recognition. In view of this, microspheres coated with lipid membranes were immobilized in HSA-supported lipid patterns via the hybridization of complementary ss-DNAs. This procedure enables to transfer solid materials to a soft surface through a specific recognition.

  8. Quantum dot-based multiphoton fluorescent pipettes for targeted neuronal electrophysiology

    PubMed Central

    Huber, Daniel; Barbic, Mladen; Macklin, John J.; Susumu, Kimihiro; Delehanty, James B.; Huston, Alan L.; Makara, Judit K.; Medintz, Igor L.

    2014-01-01

    Targeting visually-identified neurons for electrophysiological recording is a fundamental neuroscience technique; however, its potential is hampered by poor visualization of pipette tips in deep brain tissue. We describe a technique whereby quantum dots coat glass pipettes providing strong two-photon contrast at deeper penetration depths than current methods. We demonstrate utility in targeted patch-clamp recording experiments and single cell electroporation from identified rat and mouse neurons in vitro and in vivo. PMID:25326662

  9. Quantum dot-based multiphoton fluorescent pipettes for targeted neuronal electrophysiology.

    PubMed

    Andrásfalvy, Bertalan K; Galiñanes, Gregorio L; Huber, Daniel; Barbic, Mladen; Macklin, John J; Susumu, Kimihiro; Delehanty, James B; Huston, Alan L; Makara, Judit K; Medintz, Igor L

    2014-12-01

    Targeting visually identified neurons for electrophysiological recording is a fundamental neuroscience technique; however, its potential is hampered by poor visualization of pipette tips in deep brain tissue. We describe quantum dot-coated glass pipettes that provide strong two-photon contrast at deeper penetration depths than those achievable with current methods. We demonstrated the pipettes' utility in targeted patch-clamp recording experiments and single-cell electroporation of identified rat and mouse neurons in vitro and in vivo.

  10. Versatile Coating

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A radome at Logan Airport and a large parabolic antenna at the Wang Building in Massachusetts are protected from weather, corrosion and ultraviolet radiation by a coating, specially designed for antennas and radomes, known as CRC Weathertite 6000. The CRC 6000 line that emerged from Boyd Coatings Research Co., Inc. is a solid dispersion of fluorocarbon polymer and polyurethane that yields a tough, durable film with superior ultraviolet resistance and the ability to repel water and ice over a long term. Additionally, it provides resistance to corrosion, abrasion, chemical attacks and impacts. Material can be used on a variety of substrates, such as fiberglass, wood, plastic and concrete in addition to steel and aluminum. In addition Boyd Coatings sees CRC 6000 applicability as an anti-icing system coated on the leading edge of aircraft wings.

  11. Protective Coating

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Inorganic Coatings, Inc.'s K-Zinc 531 protective coating is water-based non-toxic, non-flammable and has no organic emissions. High ratio silicate formula bonds to steel, and in 30 minutes, creates a very hard ceramic finish with superior adhesion and abrasion resistance. Improved technology allows application over a minimal commercial sandblast, fast drying in high humidity conditions and compatibility with both solvent and water-based topcoats. Coating is easy to apply and provides long term protection with a single application. Zinc rich coating with water-based potassium silicate binder offers cost advantages in materials, labor hours per application, and fewer applications over a given time span.

  12. Comparison of line x-ray emission from solid and porous nano-layer coated targets irradiated by double laser pulses

    SciTech Connect

    Fazeli, R.; Mahdieh, M. H.

    2015-11-15

    Enhancement of line x-ray emission from both solid and porous iron targets induced by irradiation of single and double laser pulses is studied numerically. The line emission from laser produced plasma is calculated within the extreme ultra-violet lithography wavelength range of 13.5–13.7 nm. The effects of pre-pulse intensity and delay time between two pulses (pre-pulse and main pulse) are examined. The results show that using double pulses irradiation in the conditions of porous target can reduce the x-ray enhancement. According to the results, the use of both pre-pulse and porous target leads to efficient absorption of the laser energy. Calculations also show that such enhanced laser absorption can ionize atoms of the target material to very high degrees of ionization, leading to decrease of the density of appropriate ions that are responsible for line emission in the selected wavelength region. By increasing the target porosity, x-ray yield was more reduced.

  13. Levitation, coating, and transport of particulate materials

    SciTech Connect

    Hendricks, C.D.

    1981-10-12

    Several processes in various fields require uniformly thick coatings and layers on small particles. The particles may be used as carriers of catalytic materials (platinum or other coatings), as laser fusion targets (various polymer or metallic coatings), or for biological or other tracer or interactive processes. We have devised both molecular beam and electro-dynamic techniques for levitation of the particles during coating and electrodynamic methods of controlling and transporting the particles between coating steps and to final use locations. Both molecular beam and electrodynamic techniques are described and several advantages and limitations of each will be discussed. A short movie of an operating electrodynamic levitation and transport apparatus will be shown.

  14. Report on coating from Teer

    SciTech Connect

    Florando, J

    2006-11-09

    A trial coating run has been performed at Teer Coating LTD to assess the use of a barrel coating system as a viable option to coat multilayer spheres. Hollow glass spheres (3M K15) ranging in diameter from 70-120 microns were cleaned in a process using a 0.1 M HCl solution. Comparative photos before and after the cleaning process are shown in figure 1. Approximately, 2 liters of cleaned spheres were sent to Teer for the trial coating in their barrel coater. A picture of barrel coating system is shown in figure 2. The coating process was one layer of titanium followed by one layer of aluminum. The target thickness for each layer is 500 nm, however, no rate runs were performed to calibrate the parameters. Each layer was sputtered for 10 hours, for a total of 20 hours. After the coating process, the coated spheres were sent back to LLNL for SEM analysis. In order to quickly examine the coating in cross-section, the spheres were broken with a spatula. Photos of the broken spheres are shown in Fig 3. One sphere was chosen to look at the uniformity around the sphere. As can be seen in Figure 4, there is fairly good uniformity around the sphere. You can also distinguish between the Ti (lighter) and Al layers, however it appears the Al is quite a bit thicker. This result is not too surprising because in general Al deposits faster than Ti. Figure 4 also shows the surface morphology of the top Al layer. Although it is still quite rough, it appears to be smoother than the Teer coating with just Al on glass. Based on this analysis, we believe that the barrel coating system can produce uniform coatings and is the correct deposition configuration to coat large quantities of microspheres. However, given the variation in thickness and surface roughness of the current coatings, the process needs further development in order to produce the high quality multilayers required. Other variables including optimum material combinations, layer pair thickness, optimum surface preparation

  15. In vivo visualization of endogenous miR-21 using hyaluronic acid-coated graphene oxide for targeted cancer therapy.

    PubMed

    Hwang, Do Won; Kim, Han Young; Li, Fangyuan; Park, Ji Yong; Kim, Dohyun; Park, Jae Hyung; Han, Hwa Seung; Byun, Jung Woo; Lee, Yun-Sang; Jeong, Jae Min; Char, Kookheon; Lee, Dong Soo

    2017-03-01

    Oncogene-targeted nucleic acid therapy has been spotlighted as a new paradigm for cancer therapeutics. However, in vivo delivery issues and uncertainty of therapeutic antisense drug reactions remain critical hurdles for a successful targeted cancer therapy. In this study, we developed a fluorescence-switchable theranostic nanoplatform using hyaluronic acid (HA)-conjugated graphene oxide (GO), which is capable of both sensing oncogenic miR-21 and inhibiting its tumorigenicity simultaneously. Cy3-labeled antisense miR-21 peptide nucleic acid (PNA) probes loaded onto HA-GO (HGP21) specifically targeted CD44-positive MBA-MB231 cells and showed fluorescence recovery by interacting with endogenous miR-21 in the cytoplasm of the MBA-MB231 cells. Knockdown of endogenous miR-21 by HGP21 led to decreased proliferation and reduced migration of cancer cells, as well as the induction of apoptosis, with enhanced PTEN levels. Interestingly, in vivo fluorescence signals markedly recovered 3 h after the intravenous delivery of HGP21 and displayed signals more than 5-fold higher than those observed in the HGPscr-treated group of tumor-bearing mice. These findings demonstrate the possibility of using the HGP nanoplatform as a cancer theranostic tool in miRNA-targeted therapy.

  16. The impact of coating architecture on the hardness, friction and wear resistance of hard and tribological nanocomposite coatings

    NASA Astrophysics Data System (ADS)

    Endrino, Jose Luis

    Future generations of mechanical systems will place new demands on the tribological performance of interacting surfaces. Vapor-deposited surface coatings can provide extended lifetimes, increased efficiencies and energy savings for mechanical components and tools. These benefits can also be extended to space mechanisms and satellites with the use of vacuum solid lubricants. The material properties of surface coatings such as hardness, friction, and wear resistance in a particular environment are influenced by the characteristics of the coating microstructure which include density, grain size, grain boundary chemistry, porosity, and grain orientation. In this research effort bias sputter deposition, co-sputtering, and magnetron sputtering-pulsed laser deposition are used to deposit and control the formation of composite coating architectures. The developed microstructures were studied by x-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Mechanical and tribological tests included nanoindentation and pin-on-disk. Results were analyzed in relation to the coatings' chemical composition and microstructure with the objective of establishing structure-property relations for these films. Hard coatings presented in this thesis include carbides that form a solid solution (Ti-Hf-C) as well as carbides that form composite microstructures (WC-SiC, HfC-SiC). Hardness measurements on these films indicated the potential of transition metal carbide-silicon carbide composites to be utilized as protective coatings. With the use of a substrate bias potential, a hardness of over 35 GPa was achieved for some HfC-SiC samples. By co-depositing from carbide and silver targets, composite tribological coatings (e.g. SiC-Ag, WC-Ag, TiC-Ag, HfC-Ag) were developed. These systems revealed how critical materials selection can be in the determination of a coating's architecture, and how carbide-silver films can be used to provide low friction

  17. Tests Of Protective Coats For Carbon Steel

    NASA Technical Reports Server (NTRS)

    Macdowell, Louis G., III

    1995-01-01

    Report describes laboratory and field tests of candidate paints (primers, tie coats, and topcoats) for use in protecting carbon-steel structures against corrosion in seaside environment at Kennedy Space Center. Coating materials selected because of utility in preventing corrosion, also on basis of legal requirements, imposed in several urban areas, for reduction of volatile organic contents.

  18. Tests Of Protective Coats For Carbon Steel

    NASA Technical Reports Server (NTRS)

    Macdowell, Louis G., III

    1995-01-01

    Report describes laboratory and field tests of candidate paints (primers, tie coats, and topcoats) for use in protecting carbon-steel structures against corrosion in seaside environment at Kennedy Space Center. Coating materials selected because of utility in preventing corrosion, also on basis of legal requirements, imposed in several urban areas, for reduction of volatile organic contents.

  19. A Novel Assay for Screening Inhibitors Targeting HIV Integrase LEDGF/p75 Interaction Based on Ni2+ Coated Magnetic Agarose Beads

    PubMed Central

    Dawei, Zhang; Hongqiu, He; Mengmeng, Liu; Zhixia, Meng; Shunxing, Guo

    2016-01-01

    HIV-1 integrase (IN) plays an essential role in viral replication and thus serves as an important target for chemotherapeutic intervention against HIV-1 infection. However, the current three clinical IN inhibitors, raltegravir, elvitegravir and dolutegravir share the same inhibitory mechanism, resulting in a common clinical resistance profile which have emerged in infected patients receiving treatment. Therefore, it is important to develop small molecule inhibitors that impair IN function with distinct mechanisms of action. In this work, a magnetic-beads based biochemical assay targeting the protein-protein interaction (PPI) between HIV IN and the cellular cofactor LEDGF/p75 was developed for identification of HIV-1 IN inhibitors. Furthermore, a library containing 1000 US. Food and Drug Administration (FDA)-approved drugs currently used for human medication was screened to identify inhibitors targeting the PPI. The assay was proved to be quite robust and with the novel assay we successfully identified dexlansoprazole (IC50 of 4.8 μM), a FDA-approved proton pump inhibitor, as a potential inhibitor for the PPI between IN and LEDGF/p75, which bound to the LEDGF/p75 partner with a kinetic dissociation (Kd) constant of 330 nM ± 2.6 nM. PMID:27633629

  20. Protective Coatings

    NASA Technical Reports Server (NTRS)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  1. Nanostructured Coatings

    NASA Astrophysics Data System (ADS)

    Rivière, J.-P.

    In many branches of technology where surfaces are playing a growing role, the use of coatings is often the only way to provide surfaces with specific functional properties. For example, the austenitic stainless steels or titanium alloys exhibit poor resistance to wear and low hardness values, which limits the field of applications. The idea then is to develop new solutions which would improve the mechanical performance and durability of objects used in contact and subjected to mechanical forces in hostile gaseous or liquid environments. Hard coatings are generally much sought after to enhance the resistance to wear and corrosion. They are of particular importance because they constitute a class of protective coatings which is already widely used on an industrial scale to improve the hardness and lifetime of cutting tools.

  2. Gold Coating

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Epner Technology Inc. responded to a need from Goddard Space Flight Center for the ultimate in electroplated reflectivity needed for the Mars Global Surveyor Mars Orbiter Laser Altimeter (MOLA). Made of beryllium, the MOLA mirror was coated by Epner Technology Laser Gold process, specially improved for the project. Improved Laser Gold- coated reflectors have found use in an epitaxial reactor built for a large semiconductor manufacturer as well as the waveguide in Braun-Thermoscan tympanic thermometer and lasing cavities in various surgical instruments.

  3. Throughput increase by adjustment of the BARC drying time with coat track process

    NASA Astrophysics Data System (ADS)

    Brakensiek, Nickolas L.; Long, Ryan

    2005-05-01

    Throughput of a coater module within the coater track is related to the solvent evaporation rate from the material that is being coated. Evaporation rate is controlled by the spin dynamics of the wafer and airflow dynamics over the wafer. Balancing these effects is the key to achieving very uniform coatings across a flat unpatterned wafer. As today"s coat tracks are being pushed to higher throughputs to match the scanner, the coat module throughput must be increased as well. For chemical manufacturers the evaporation rate of the material depends on the solvent used. One measure of relative evaporation rates is to compare flash points of a solvent. The lower the flash point, the quicker the solvent will evaporate. It is possible to formulate products with these volatile solvents although at a price. Shipping and manufacturing a more flammable product increase chances of fire, thereby increasing insurance premiums. Also, the end user of these chemicals will have to take extra precautions in the fab and in storage of these more flammable chemicals. An alternative coat process is possible which would allow higher throughput in a distinct coat module without sacrificing safety. A tradeoff is required for this process, that being a more complicated coat process and a higher viscosity chemical. The coat process uses the fact that evaporation rate depends on the spin dynamics of the wafer by utilizing a series of spin speeds that first would set the thickness of the material followed by a high spin speed to remove the residual solvent. This new process can yield a throughput of over 150 wafers per hour (wph) given two coat modules. The thickness uniformity of less than 2 nm (3 sigma) is still excellent, while drying times are shorter than 10 seconds to achieve the 150 wph throughput targets.

  4. Electrostatic coating technologies for food processing.

    PubMed

    Barringer, Sheryl A; Sumonsiri, Nutsuda

    2015-01-01

    The application of electrostatics in both powder and liquid coating can improve the quality of food, such as its appearance, aroma, taste, and shelf life. Coatings can be found most commonly in the snack food industry, as well as in confectionery, bakery, meat and cheese processing. In electrostatic powder coating, the most important factors influencing coating quality are powder particle size, density, flowability, charge, and resistivity, as well as the surface properties and characteristics of the target. The most important factors during electrostatic liquid coating, also known as electrohydrodynamic coating, include applied voltage and electrical resistivity and viscosity of the liquid. A good understanding of these factors is needed for the design of optimal coating systems for food processing.

  5. Nitrogen implantation effects on the chemical bonding and hardness of boron and boron nitride coatings

    SciTech Connect

    Anders, S; Felter, T; Hayes, J; Jankowski, A F; Patterson, R; Poker, D; Stamler, T

    1999-02-08

    Boron nitride (BN) coatings are deposited by the reactive sputtering of fully dense, boron (B) targets utilizing an argon-nitrogen (Ar-N{sub 2}) reactive gas mixture. Near-edge x-ray absorption fine structure analysis reveals features of chemical bonding in the B 1s photoabsorption spectrum. Hardness is measured at the film surface using nanoindentation. The BN coatings prepared at low, sputter gas pressure with substrate heating are found to have bonding characteristic of a defected hexagonal phase. The coatings are subjected to post-deposition nitrogen (N{sup +} and N{sub 2}{sup +}) implantation at different energies and current densities. The changes in film hardness attributed to the implantation can be correlated to changes observed in the B 1s NEXAFS spectra.

  6. System parameters germane to relativistic klystron amplifiers: how the utility of pulse energy depends on pulse duration, the target, and the atmosphere

    NASA Astrophysics Data System (ADS)

    Myers, John M.

    1994-05-01

    Relativistic klystron amplifiers (RKAs) at a variety of carrier wavelengths and pulse durations appear feasible to supply microwave pulses to an array of antennas acting as a beam weapon against targets at or above 100 km in altitude. In order to avoid voltage breakdown in the atmosphere, the array area must be large enough to converge the beam, producing a higher energy flux on target than at intermediate altitudes susceptible to breakdown. The area required depends on the physics of atmospheric ionization and on the pulse duration and the carrier wavelength of the RKA. A quantitative statement of the dependence of array area on relevant parameters is presented. The energy per RKA pulse that is usable without delay lines is determined here as a function of RKA pulse duration and wavelength. Changing the pulse length from 160 ns to 1 microsecond(s) and shortening the wavelength raise the energy usable without delay lines by a factor of 1000.

  7. Uniform spray coating for large tanks

    NASA Technical Reports Server (NTRS)

    Carter, J. M.

    1977-01-01

    System employs spray facility located within ventilated plastic booth to uniformly coat exterior of large cylindrical tanks with polyurethane foam insulation. Coating target is rotated on turntable while movable spray guns apply overlapping spirals of foam. Entire operation may be controlled by single operator from remote station.

  8. Uniform spray coating for large tanks

    NASA Technical Reports Server (NTRS)

    Carter, J. M.

    1977-01-01

    System employs spray facility located within ventilated plastic booth to uniformly coat exterior of large cylindrical tanks with polyurethane foam insulation. Coating target is rotated on turntable while movable spray guns apply overlapping spirals of foam. Entire operation may be controlled by single operator from remote station.

  9. Influenza nucleoprotein DNA vaccination by a skin targeted, dry coated, densely packed microprojection array (Nanopatch) induces potent antibody and CD8(+) T cell responses.

    PubMed

    Fernando, Germain J P; Zhang, Jin; Ng, Hwee-Ing; Haigh, Oscar L; Yukiko, Sally R; Kendall, Mark A F

    2016-09-10

    DNA vaccines have many advantages such as thermostability and the ease and rapidity of manufacture; for example, in an influenza pandemic situation where rapid production of vaccine is essential. However, immunogenicity of DNA vaccines was shown to be poor in humans unless large doses of DNA are used. If a highly efficacious DNA vaccine delivery system could be identified, then DNA vaccines have the potential to displace protein vaccines. In this study, we show in a C57BL/6 mouse model, that the Nanopatch, a microprojection array of high density (>21,000 projections/cm(2)), could be used to deliver influenza nucleoprotein DNA vaccine to skin, to generate enhanced antigen specific antibody and CD8(+) T cell responses compared to the conventional intramuscular (IM) delivery by the needle and syringe. Antigen specific antibody was measured using ELISA assays of mice vaccinated with a DNA plasmid containing the nucleoprotein gene of influenza type A/WSN/33 (H1N1). Antigen specific CD8(+) T cell responses were measured ex-vivo in splenocytes of mice using IFN-γ ELISPOT assays. These results and our previous antibody and CD4(+) T cell results using the Nanopatch delivered HSV DNA vaccine indicate that the Nanopatch is an effective delivery system of general utility that could potentially be used in humans to increase the potency of the DNA vaccines.

  10. Functional Characterization of Sodium-dependent Multivitamin Transporter (SMVT) in MDCK-MDR1 cells and its Utilization as a Target for Drug Delivery

    PubMed Central

    Luo, Shuanghui; Kansara, Viral S.; Zhu, Xiaodong; Pal, Dhananjay; Mitra, Ashim. K.

    2008-01-01

    The objective of this research is to characterize a sodium-dependent multivitamin transporter (SMVT) in MDCK-MDR1 cells (Madin-Darby canine kidney cells transfected with the human MDR1 gene) and to investigate the feasibility of utilizing MDCK-MDR1 cell line as an in vitro model to study the permeability of biotin-conjugated prodrugs of anti-HIV protease inhibitors. Mechanism of [3H] biotin uptake and transport was delineated. Transepithelial permeability of the biotin conjugated prodrug i.e. biotin-saquinavir was also studied. Reverse transcription-polymerase chain reaction (RT-PCR) was carried out to confirm the existence of SMVT in MDCK-MDR1 cells. Biotin uptake was Na+, pH, and temperature dependent, but energyindependent. Transepithelial transport studies of biotin-saquinavir in MDCK-MDR1, wild type MDCK, and Caco-2 cells revealed that permeability of biotin-saquinavir was similar in all three cell lines. A band of SMVT mRNA at 862 bp was identified by RT-PCR. A sodium-dependent multivitamin transporter, SMVT, responsible for biotin uptake and transport, was identified and functionally characterized in MDCK-MDR1 cells. Therefore, MDCK-MDR1 cell line may be utilized as an in vitro model to study the permeability of biotin conjugated prodrugs such as HIV protease inhibitors. PMID:16749865

  11. Probability of detection of defects in coatings with electronic shearography

    NASA Technical Reports Server (NTRS)

    Russell, S. S.; Lansing, M. D.; Horton, C. M.; Gnacek, W. J.

    1995-01-01

    The goal of this research was to utilize statistical methods to evaluate the probability of detection (POD) of defects in coatings using electronic shearography. The coating system utilized in the POD studies was to be the paint system currently utilized on the external casings of the NASA space transportation system reusable solid rocket motor boosters. The population of samples was to be large enough to determine the minimum defect size for 90-percent POD of 95-percent confidence POD on these coatings. Also, the best methods to excite coatings on aerospace components to induce deformations for measurement by electronic shearography were to be determined.

  12. Probability of detection of defects in coatings with electronic shearography

    NASA Technical Reports Server (NTRS)

    Maddux, Gary A.; Horton, Charles M.; Lansing, Matthew D.; Gnacek, William J.; Newton, Patrick L.

    1994-01-01

    The goal of this research was to utilize statistical methods to evaluate the probability of detection (POD) of defects in coatings using electronic shearography. The coating system utilized in the POD studies was to be the paint system currently utilized on the external casings of the NASA Space Transportation System (STS) Revised Solid Rocket Motor (RSRM) boosters. The population of samples was to be large enough to determine the minimum defect size for 90 percent probability of detection of 95 percent confidence POD on these coatings. Also, the best methods to excite coatings on aerospace components to induce deformations for measurement by electronic shearography were to be determined.

  13. Efficacy of dialysis in peritoneal dialysis: utility of bioimpedance to calculate Kt/V and the search for a target Kt.

    PubMed

    Martínez Fernández, G; Ortega Cerrato, A; Masiá Mondéjar, J; Pérez Rodríguez, A; Llamas Fuentes, F; Gómez Roldán, C; Pérez-Martínez, Juan

    2013-04-01

    To calculate Kt/V, volume (V) is usually obtained by Watson formula, but bioimpedance spectroscopy (BIS) is a simple and applicable technique to determinate V, along with other hydration and nutrition parameters, in peritoneal dialysis (PD) patients. Dialysis efficacy can also be measured with Kt, but no experience exists in PD, so there is no reference/target value for Kt that must be achieved in these patients to be considered adequately dialyzed. We evaluated the efficacy of PD with Kt/V using Watson formula and BIS for V calculation, assessed hydration status in a PD unit by data obtained by BIS, and attempted to find a reference Kt from the Kt/V previously obtained by BIS. In this observational prospective study of 78 PD patients, we measured V using BIS (V bis) and Watson formula (V w) and calculated weekly Kt/V using both volumes (Kt/V bis/V bis and Kt/V w). With the BIS technique, we obtained and subsequently analyzed other hydration status parameters. We achieved a reference Kt, extrapolating the value desired (weekly Kt/V 1.7) to the target Kt using the simple linear regression statistical technique, basing it on the results of the previously calculated Pearson's linear correlation coefficient. Volume was 1.8 l higher by Watson formula than with BIS (p < 0.001). Weekly Kt/V bis was 2.33 ± 0.68, and mean weekly Kt/V w was 2.20 ± 0.63 (p < 0.0001); 60.25 % of patients presented overhydration according to the BIS study (OH >1.1 l). The target value of Kt for the reference weekly Kt/V bis (1.7) was 64.87 l. BIS is a simple, applicable technique for calculating V in dialysis that can be especially useful in PD patients compared with the anthropometric formulas, by the abnormally distributed body water in these patients. Other parameters obtained by BIS will serve to assess both the distribution of body volume and nutritional status in the clinical setting. The target Kt value obtained from Kt/V bis allowed us to measure the efficacy of PD in a practical way

  14. Microneedle Coating Techniques for Transdermal Drug Delivery

    PubMed Central

    Haj-Ahmad, Rita; Khan, Hashim; Arshad, Muhammad Sohail; Rasekh, Manoochehr; Hussain, Amjad; Walsh, Susannah; Li, Xiang; Chang, Ming-Wei; Ahmad, Zeeshan

    2015-01-01

    Drug administration via the transdermal route is an evolving field that provides an alternative to oral and parenteral routes of therapy. Several microneedle (MN) based approaches have been developed. Among these, coated MNs (typically where drug is deposited on MN tips) are a minimally invasive method to deliver drugs and vaccines through the skin. In this review, we describe several processes to coat MNs. These include dip coating, gas jet drying, spray coating, electrohydrodynamic atomisation (EHDA) based processes and piezoelectric inkjet printing. Examples of process mechanisms, conditions and tested formulations are provided. As these processes are independent techniques, modifications to facilitate MN coatings are elucidated. In summary, the outcomes and potential value for each technique provides opportunities to overcome formulation or dosage form limitations. While there are significant developments in solid degradable MNs, coated MNs (through the various techniques described) have potential to be utilized in personalized drug delivery via controlled deposition onto MN templates. PMID:26556364

  15. Thermal barrier coatings for heat engine components

    NASA Technical Reports Server (NTRS)

    Levine, S. R.; Miller, R. A.; Hodge, P. E.

    1980-01-01

    A comprehensive NASA-Lewis program of coating development for aircraft gas turbine blades and vanes is presented. Improved ceramic layer compositions are investigated, along the MCrAlY bond films and the methods of uniform deposition of the coatings; the thermomechanical and fuel impurity tolerance limits of the coatings are being studied. Materials include the ZrO2-Y2O3/NiCrAlY system; the effects of the bond coat and zirconia composition on coating life and Mach 1 burner rig test results are discussed. It is concluded that Diesel engines can also utilize thermal barrier coatings; they have been used successfully on piston crowns and exhaust valves of shipboard engines to combat lower grade fuel combustion corrosion.

  16. Microneedle Coating Techniques for Transdermal Drug Delivery.

    PubMed

    Haj-Ahmad, Rita; Khan, Hashim; Arshad, Muhammad Sohail; Rasekh, Manoochehr; Hussain, Amjad; Walsh, Susannah; Li, Xiang; Chang, Ming-Wei; Ahmad, Zeeshan

    2015-11-05

    Drug administration via the transdermal route is an evolving field that provides an alternative to oral and parenteral routes of therapy. Several microneedle (MN) based approaches have been developed. Among these, coated MNs (typically where drug is deposited on MN tips) are a minimally invasive method to deliver drugs and vaccines through the skin. In this review, we describe several processes to coat MNs. These include dip coating, gas jet drying, spray coating, electrohydrodynamic atomisation (EHDA) based processes and piezoelectric inkjet printing. Examples of process mechanisms, conditions and tested formulations are provided. As these processes are independent techniques, modifications to facilitate MN coatings are elucidated. In summary, the outcomes and potential value for each technique provides opportunities to overcome formulation or dosage form limitations. While there are significant developments in solid degradable MNs, coated MNs (through the various techniques described) have potential to be utilized in personalized drug delivery via controlled deposition onto MN templates.

  17. Assessment of EGFR/HER2 dimerization by FRET-FLIM utilizing Alexa-conjugated secondary antibodies in relation to targeted therapies in cancers.

    PubMed

    Waterhouse, Benjamin R; Gijsen, Merel; Barber, Paul R; Tullis, Iain D C; Vojnovic, Borivoj; Kong, Anthony

    2011-09-01

    The expression level of the HER family is unreliable as a predictive marker for targeted therapies in cancer. Thus, there is a need to develop other biomarkers, which can be used to accurately select responsive patients for targeted therapies. The HER dimerization status may be more important than HER receptor expression per se in determining sensitivity or resistance to a given therapeutic agent. The aim of the study is to develop a FRET assay using dye conjugated secondary antibodies to assess HER receptor dimerization. Using primary antibodies from different species in conjunction with Alexa488 and Alexa546 conjugated secondary antibodies, we validated our EGFR/HER2 dimerization assay in three cell lines, EGFR positive A431 cells as well as HER2 positive breast cell lines BT474 and SKBR3 cells. Finally, we applied our assay to assess EGFR/HER2 dimerization in paraffin embedded cell pellets. Our results show promise for the assay to be applied to tumor samples in order to assess the prognostic significance and predictive value of HER receptor dimerization in various cancers.

  18. COATING METHOD

    DOEpatents

    Townsend, R.G.

    1959-08-25

    A method is described for protectively coating beryllium metal by etching the metal in an acid bath, immersing the etched beryllium in a solution of sodium zincate for a brief period of time, immersing the beryllium in concentrated nitric acid, immersing the beryhlium in a second solution of sodium zincate, electroplating a thin layer of copper over the beryllium, and finally electroplating a layer of chromium over the copper layer.

  19. Hybrid Calcium Phosphate Coatings for Titanium Implants

    NASA Astrophysics Data System (ADS)

    Kharapudchenko, E.; Ignatov, V.; Ivanov, V.; Tverdokhlebov, S.

    2017-01-01

    Hybrid multilayer coatings were obtained on titanium substrates by the combination of two methods: the micro-arc oxidation in phosphoric acid solution with the addition of calcium compounds to high supersaturated state and RF magnetron sputtering of the target made of synthetic hydroxyapatite. 16 different groups of coatings were formed on titanium substrates and in vitro studies were conducted in accordance with ISO 23317 in the solution simulating body fluid. The studies using SEM, XRD of the coatings of the samples before and after exposure to SBF were performed. The features of morphology, chemical and phase composition of the studied coatings are shown.

  20. Diamond coated artificial cardiovascular devices

    PubMed Central

    Zeng, Hongjun; Jarvik, Robert; Catausan, Grace; Moldovan, Nicolaie; Carlisle, John

    2016-01-01

    Ultrananocrystalline diamond (UNCD), an extremely smooth, low cost diamond coating was successfully developed herein for antithrombogenic application which requires high biocompatibility, low wear, low friction, and chemical inertness. The substrate materials utilized in the Jarvik 2000 ventricular assist device (VAD), silicon carbide and titanium alloy, provide an excellent substrate match for UNCD integration. The paper addresses the development of medical-quality UNCD films to significantly improve the knowledge base regarding the defect mechanisms of UNCD films, to reduce or eliminate known wear-inducing imperfections in the film, and to thoroughly characterize and test the films as well as assembled UNCD-coated VADs. After the defect reduction and seeding experiments to improve film adhesion and coating quality, the best candidate deposition method has been down-selected for coating and assembly of VAD parts from Jarvik Heart. The coated and assembled devices have been tested with mechanical and blood-simulating fluid hydrodynamic testing at Jarvik Heart for full verification of the new coating technology. UNCD interface takes advantage of combining unmatched durability and antithrombogenicity. PMID:27867245

  1. Targeted Next-Generation Sequencing of Plasma DNA from Cancer Patients: Factors Influencing Consistency with Tumour DNA and Prospective Investigation of Its Utility for Diagnosis

    PubMed Central

    Kaisaki, Pamela J.; Cutts, Anthony; Popitsch, Niko; Camps, Carme; Pentony, Melissa M.; Wilson, Gareth; Page, Suzanne; Kaur, Kulvinder; Vavoulis, Dimitris; Henderson, Shirley; Gupta, Avinash; Middleton, Mark R.; Karydis, Ioannis; Talbot, Denis C.; Schuh, Anna; Taylor, Jenny C.

    2016-01-01

    Use of circulating tumour DNA (ctDNA) as a liquid biopsy has been proposed for potential identification and monitoring of solid tumours. We investigate a next-generation sequencing approach for mutation detection in ctDNA in two related studies using a targeted panel. The first study was retrospective, using blood samples taken from melanoma patients at diverse timepoints before or after treatment, aiming to evaluate correlation between mutations identified in biopsy and ctDNA, and to acquire a first impression of influencing factors. We found good concordance between ctDNA and tumour mutations of melanoma patients when blood samples were collected within one year of biopsy or before treatment. In contrast, when ctDNA was sequenced after targeted treatment in melanoma, mutations were no longer found in 9 out of 10 patients, suggesting the method might be useful for detecting treatment response. Building on these findings, we focused the second study on ctDNA obtained before biopsy in lung patients, i.e. when a tentative diagnosis of lung cancer had been made, but no treatment had started. The main objective of this prospective study was to evaluate use of ctDNA in diagnosis, investigating the concordance of biopsy and ctDNA-derived mutation detection. Here we also found positive correlation between diagnostic lung biopsy results and pre-biopsy ctDNA sequencing, providing support for using ctDNA as a cost-effective, non-invasive solution when the tumour is inaccessible or when biopsy poses significant risk to the patient. PMID:27626278

  2. Understanding human papillomavirus vaccination intentions: comparative utility of the theory of reasoned action and the theory of planned behavior in vaccine target age women and men.

    PubMed

    Fisher, William A; Kohut, Taylor; Salisbury, Claire M A; Salvadori, Marina I

    2013-10-01

    Human papillomavirus (HPV) is an exceedingly prevalent sexually transmitted infection with serious medical, sexual, and relationship consequences. HPV vaccine protection is available but vaccine uptake is very inconsistent. This research applies two major theories of health behavior uptake, the Theory of Reasoned Action and the Theory of Planned Behavior, in an effort to understand intentions to receive HPV vaccine among vaccine target age women and men. The Theory of Reasoned Action asserts that attitudes toward HPV vaccination and perceptions of social support for HPV vaccination are the determinants of intentions to be vaccinated, whereas the Theory of Planned Behavior holds that attitudes toward vaccination, perceptions of social support for vaccination, and perceived ability to get vaccinated are the determinants of intentions to be vaccinated. Canadian university men (N=118) and women (N=146) in the HPV vaccine target age range took part in this correlational study online. Participants completed standard measures of attitudes toward HPV vaccination, perceptions of social support for vaccination, perceived ability to get vaccinated, beliefs about vaccination, and intentions to be vaccinated in the coming semester. Findings confirmed the propositions of the Theory of Reasoned Action and indicated that attitudes toward undergoing HPV vaccination and perceptions of social support for undergoing HPV vaccination contributed uniquely to the prediction of women's (R2=0.53) and men's (R2=0.44) intentions to be vaccinated in the coming semester. Clinical and public health education should focus on strengthening attitudes and perceptions of social support for HPV vaccination, and on the basic beliefs that appear to underlie attitudes and perceptions of social support for HPV vaccination, in efforts to promote HPV vaccine uptake. © 2013 International Society for Sexual Medicine.

  3. Coat Measurements and Analysis

    DTIC Science & Technology

    1975-11-01

    8217*^*********** p—W- " --"’■ « m" < lll»iili»i|FIJWWWWTOWPBBji^p Static deflection tests of the focus actuator in a Twyman -Green interferometer are shown in...BORESIGHT AXIS FORMED ARRAY PATTERN ON BORESIGHT ELEMENT PATTERN ARRAY SIDELOBE ► DISTANCE ’ i Fig. 7. Target intensity patterns...peak-null distances , w = 1/T e a ; r c c for T the 10% to 90% convergence time of the COAT phase controls, and sine u = sin u/u

  4. The validation and utility of a quantitative one-step multiplex RT real-time PCR targeting Rotavirus A and Norovirus

    PubMed Central

    Dung, Tran Thi Ngoc; Phat, Voong Vinh; Nga, Tran Vu Thieu; My, Phan Vu Tra; Duy, Pham Thanh; Campbell, James I.; Thuy, Cao Thu; Hoang, Nguyen Van Minh; Van Minh, Pham; Le Phuc, Hoang; Tuyet, Pham Thi Ngoc; Vinh, Ha; Kien, Duong Thi Hue; Huy, Huynh Le Anh; Vinh, Nguyen Thanh; Nga, Tran Thi Thu; Hau, Nguyen Thi Thu; Chinh, Nguyen Tran; Thuong, Tang Chi; Tuan, Ha Manh; Simmons, Cameron; Farrar, Jeremy J.; Baker, Stephen

    2013-01-01

    Rotavirus (RoV) and Norovirus (NoV) are the main causes of viral gastroenteritis. Currently, there is no validated multiplex real-time PCR that can detect and quantify RoV and NoV simultaneously. The aim of the study was to develop, validate, and internally control a multiplex one-step RT real-time PCR to detect and quantify RoV and NoV in stool samples. PCR sensitivity was assessed by comparing amplification against the current gold standard, enzyme immunoassay (EIA), on stool samples from 94 individuals with diarrhea and 94 individuals without diarrhea. PCR detected 10% more RoV positive samples than EIA in stools samples from patients with diarrhea. PCR detected 23% more NoV genogroup II positive samples from individuals with diarrhea and 9% more from individuals without diarrhea than EIA, respectively. Genotyping of the PCR positive/EIA negative samples suggested the higher rate of PCR positivity, in comparison to EIA, was due to increased sensitivity, rather than nonspecific hybridization. Quantitation demonstrated that the viral loads of RoV and NoV in the stools of diarrheal patients were an order of magnitude greater than in individuals without diarrhea. This internally controlled real-time PCR method is robust, exhibits a high degree of reproducibility, and may have a greater utility and sensitivity than commercial EIA kits. PMID:23046990

  5. The validation and utility of a quantitative one-step multiplex RT real-time PCR targeting rotavirus A and norovirus.

    PubMed

    Dung, Tran Thi Ngoc; Phat, Voong Vinh; Nga, Tran Vu Thieu; My, Phan Vu Tra; Duy, Pham Thanh; Campbell, James I; Thuy, Cao Thu; Hoang, Nguyen Van Minh; Van Minh, Pham; Le Phuc, Hoang; Tuyet, Pham Thi Ngoc; Vinh, Ha; Kien, Duong Thi Hue; Huy, Huynh Le Anh; Vinh, Nguyen Thanh; Nga, Tran Thi Thu; Hau, Nguyen Thi Thu; Chinh, Nguyen Tran; Thuong, Tang Chi; Tuan, Ha Manh; Simmons, Cameron; Farrar, Jeremy J; Baker, Stephen

    2013-01-01

    Rotavirus (RoV) and Norovirus (NoV) are the main causes of viral gastroenteritis. Currently, there is no validated multiplex real-time PCR that can detect and quantify RoV and NoV simultaneously. The aim of the study was to develop, validate, and internally control a multiplex one-step RT real-time PCR to detect and quantify RoV and NoV in stool samples. PCR sensitivity was assessed by comparing amplification against the current gold standard, enzyme immunoassay (EIA), on stool samples from 94 individuals with diarrhea and 94 individuals without diarrhea. PCR detected 10% more RoV positive samples than EIA in stools samples from patients with diarrhea. PCR detected 23% more NoV genogroup II positive samples from individuals with diarrhea and 9% more from individuals without diarrhea than EIA, respectively. Genotyping of the PCR positive/EIA negative samples suggested the higher rate of PCR positivity, in comparison to EIA, was due to increased sensitivity, rather than nonspecific hybridization. Quantitation demonstrated that the viral loads of RoV and NoV in the stools of diarrheal patients were an order of magnitude greater than in individuals without diarrhea. This internally controlled real-time PCR method is robust, exhibits a high degree of reproducibility, and may have a greater utility and sensitivity than commercial EIA kits. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Labview utilities

    SciTech Connect

    Persaud, Arun

    2011-09-30

    The software package provides several utilities written in LabView. These utilities don't form independent programs, but rather can be used as a library or controls in other labview programs. The utilities include several new controls (xcontrols), VIs for input and output routines, as well as other 'helper'-functions not provided in the standard LabView environment.

  7. Liposomes targeted by fusion phage proteins.

    PubMed

    Jayanna, Prashanth K; Torchilin, Vladimir P; Petrenko, Valery A

    2009-03-01

    Targeting of nanocarriers has long been sought after to improve the therapeutic indices of anticancer drugs. Here we provide the proof of principle for a novel approach of nanocarrier targeting through their fusion with target-specific phage coat proteins. The source of the targeted phage coat proteins are landscape phage libraries--collections of recombinant filamentous phages with foreign random peptides fused to all 4000 copies of the major coat protein. We exploit in our approach the intrinsic physicochemical properties of the phage major coat protein as a typical membrane protein. Landscape phage peptides specific for specific tumors can be obtained by affinity selection, and purified fusion coat proteins can be assimilated into liposomes to obtain specific drug-loaded nanocarriers. As a paradigm for inceptive experiments, a streptavidin-specific phage peptide selected from a landscape phage library was incorporated into approximately 100-nm liposomes. Targeting of liposomes was proved by their specific binding to streptavidin-coated beads.

  8. Plasma-sprayed coatings

    SciTech Connect

    Herman, H.

    1988-09-01

    Plasma spraying is one way to apply protective coatings. The hot, high-speed flame of a plasma gun can melt a powder of almost any ceramic or metal and spray it to form a coating for protection against corrosion, wear or high temperature. The technique carries much less risk of degrading the coating and substrate than many other high-temperature processes do, because the gas in the plasma flame is chemically inert and the target can be kept fairly cool. And yet a plasma gun can be only a little more cumbersome than a paint sprayer. Investigators are applying this technique to new materials. The General Electric Company is using vacuum plasma spraying to make freestanding components: intricate aircraft engine parts formed by plasma-spraying a superalloy on a removable substrate. Other workers spray ceramic particles or fibers and metal powder simulatious wrong, stiff composite materials: the ceramic particles dispersed in a matrix of metal. The author and colleagues at the U.S. Naval Research Laboratory have fabricated a thick film of high-temperature superconductor by plasma-spraying the compound in the form of a powder. 7 figs.

  9. Thermal radiative properties: Coatings.

    NASA Technical Reports Server (NTRS)

    Touloukian, Y. S.; Dewitt, D. P.; Hernicz, R. S.

    1972-01-01

    This volume consists, for the most part, of a presentation of numerical data compiled over the years in a most comprehensive manner on coatings for all applications, in particular, thermal control. After a moderately detailed discussion of the theoretical nature of the thermal radiative properties of coatings, together with an overview of predictive procedures and recognized experimental techniques, extensive numerical data on the thermal radiative properties of pigmented, contact, and conversion coatings are presented. These data cover metallic and nonmetallic pigmented coatings, enamels, metallic and nonmetallic contact coatings, antireflection coatings, resin coatings, metallic black coatings, and anodized and oxidized conversion coatings.

  10. Are there better guidelines for allocation in liver transplantation? A novel score targeting justice and utility in the model for end-stage liver disease era.

    PubMed

    Dutkowski, Philipp; Oberkofler, Christian E; Slankamenac, Ksenija; Puhan, Milo A; Schadde, Erik; Müllhaupt, Beat; Geier, Andreas; Clavien, Pierre A

    2011-11-01

    To design a new score on risk assessment for orthotopic liver transplantation (OLT) based on both donor and recipient parameters. The balance of waiting list mortality and posttransplant outcome remains a difficult task in the era of the model for end-stage liver disease (MELD). Using the United Network for Organ Sharing database, a risk analysis was performed in adult recipients of OLT in the United States of America between 2002 and 2010 (n = 37,255). Living donor-, partial-, or combined-, and donation after cardiac death liver transplants were excluded. Next, a risk score was calculated (balance of risk score, BAR score) on the basis of logistic regression factors, and validated using our own OLT database (n = 233). Finally, the new score was compared with other prediction systems including donor risk index, survival outcome following liver transplantation, donor-age combined with MELD, and MELD score alone. Six strongest predictors of posttransplant survival were identified: recipient MELD score, cold ischemia time, recipient age, donor age, previous OLT, and life support dependence prior to transplant. The new balance of risk score stratified recipients best in terms of patient survival in the United Network for Organ Sharing data, as in our European population. The BAR system provides a new, simple and reliable tool to detect unfavorable combinations of donor and recipient factors, and is readily available before decision making of accepting or not an organ for a specific recipient. This score may offer great potential for better justice and utility, as it revealed to be superior to recent developed other prediction scores.

  11. Utilizing Targeted Mass Spectrometry to Demonstrate Asf1-Dependent Increases in Residue Specificity for Rtt109-Vps75 Mediated Histone Acetylation

    PubMed Central

    Kuo, Yin-Ming; Henry, Ryan A.; Huang, Liangqun; Chen, Xu; Stargell, Laurie A.; Andrews, Andrew J.

    2015-01-01

    In Saccharomyces cerevisiae, Rtt109, a lysine acetyltransferase (KAT), associates with a histone chaperone, either Vps75 or Asf1. It has been proposed that these chaperones alter the selectivity of Rtt109 or which residues it preferentially acetylates. In the present study, we utilized a label-free quantitative mass spectrometry-based method to determine the steady-state kinetic parameters of acetylation catalyzed by Rtt109-Vps75 on H3 monomer, H3/H4 tetramer, and H3/H4-Asf1 complex. These results show that among these histone conformations, only H3K9 and H3K23 are significantly acetylated under steady-state conditions and that Asf1 promotes H3/H4 acetylation by Rtt109-Vps75. Asf1 equally increases the Rtt109-Vps75 specificity for both of these residues with a maximum stoichiometry of 1:1 (Asf1 to H3/H4), but does not alter the selectivity between these two residues. These data suggest that the H3/H4-Asf1 complex is a substrate for Rtt109-Vps75 without altering selectivity between residues. The deletion of either Rtt109 or Asf1 in vivo results in the same reduction of H3K9 acetylation, suggesting that Asf1 is required for efficient H3K9 acetylation both in vitro and in vivo. Furthermore, we found that the acetylation preference of Rtt109-Vps75 could be directed to H3K56 when those histones already possess modifications, such as those found on histones purified from chicken erythrocytes. Taken together, Vps75 and Asf1 both enhance Rtt109 acetylation for H3/H4, although via different mechanisms, but have little impact on the residue selectivity. Importantly, these results provide evidence that histone chaperones can work together via interactions with either the enzyme or the substrate to more efficiently acetylate histones. PMID:25781956

  12. Utilization of human nuclear receptors as an early counter screen for off-target activity: a case study with a compendium of 615 known drugs.

    PubMed

    Fan, Fan; Hu, Rong; Munzli, Anke; Chen, Yuan; Dunn, Robert T; Weikl, Kerstin; Strauch, Simone; Schwandner, Ralf; Afshari, Cynthia A; Hamadeh, Hisham; Nioi, Paul

    2015-06-01

    Off-target effects of drugs on nuclear hormone receptors (NHRs) may result in adverse effects in multiple organs/physiological processes. Reliable assessments of the NHR activities for drug candidates are therefore crucial for drug development. However, the highly permissive structures of NHRs for vastly different ligands make it challenging to predict interactions by examining the chemical structures of the ligands. Here, we report a detailed investigation on the agonistic and antagonistic activities of 615 known drugs or drug candidates against a panel of 6 NHRs: androgen, progesterone, estrogen α/β, and thyroid hormone α/β receptors. Our study revealed that 4.7 and 12.4% compounds have agonistic and antagonistic activities, respectively, against this panel of NHRs. Nonetheless, potent, unintended NHR hits are relatively rare among the known drugs, indicating that such interactions are perhaps not tolerated during drug development. However, we uncovered examples of compounds that unintentionally agonize or antagonize NHRs. In addition, a number of compounds showed multi-NHR activities, suggesting that the cross-talk between multiple NHRs co-operate to elicit in vivo effects. These data highlight the merits of counter screening drug candidate against NHRs during drug discovery/development.

  13. Assessment of Thermal Control and Protective Coatings

    NASA Technical Reports Server (NTRS)

    Mell, Richard J.

    2000-01-01

    This final report is concerned with the tasks performed during the contract period which included spacecraft coating development, testing, and applications. Five marker coatings consisting of a bright yellow handrail coating, protective overcoat for ceramic coatings, and specialized primers for composites (or polymer) surfaces were developed and commercialized by AZ Technology during this program. Most of the coatings have passed space environmental stability requirements via ground tests and/or flight verification. Marker coatings and protective overcoats were successfully flown on the Passive Optical Sample Assembly (POSA) and the Optical Properties Monitor (OPM) experiments flown on the Russian space station MIR. To date, most of the coatings developed and/or modified during this program have been utilized on the International Space Station and other spacecraft. For ISS, AZ Technology manufactured the 'UNITY' emblem now being flown on the NASA UNITY node (Node 1) that is docked to the Russian Zarya (FGB) utilizing the colored marker coatings (white, blue, red) developed by AZ Technology. The UNITY emblem included the US American flag, the Unity logo, and NASA logo on a white background, applied to a Beta cloth substrate.

  14. Infrared molecular binding spectroscopy realized in sorbent coated microfabricated devices

    NASA Astrophysics Data System (ADS)

    McGill, R. Andrew; Stievater, Todd H.; Pruessner, Marcel W.; Holmstrom, Scott A.; Nierenberg, Kerry; McGill, Rachel; Nguyen, Viet; Park, Doewon; Kendziora, Christopher; Furstenberg, Robert

    2014-05-01

    Sorbent materials are utilized in a range of analytical applications including coatings for preconcentrator devices, chromatography stationary phases, and as thin film transducer coatings used to concentrate analyte molecules of interest for detection. In this work we emphasize the use of sorbent materials to target absorption of analyte vapors and examine their molecular interaction with the sorbent by optically probing it with infrared (IR) light. The complex spectral changes which may occur during molecular binding of specific vapors to target sites in a sorbent can significantly aid in analyte detection. In this work a custom hydrogen-bond (HB) acidic polymer, HCSFA2, was used as the sorbent. HCSFA2 exhibits a high affinity for hazardous vapors with hydrogen-bond (HB) basic properties such as the G-nerve agents. Using bench top ATR-FTIR spectroscopy the HFIP hydroxyl stretching frequency has been observed in the mid wave infrared (MWIR) to shift by up to 700 wavenumbers when exposed to a strong HB base. The amount of shift is related to the HB basicity of the vapor. In addition, the large analyte polymer-gas partition coefficients sufficiently concentrate the analyte in the sorbent coating to allow spectral features of the analyte to be observed in the MWIR and long wave infrared (LWIR) while it is sorbed to HCSFA2. These spectral changes, induced by analyte-sorbent molecular binding, provide a rich signal feature space to consider selective detection of a wide range of chemical species as single components or complex mixtures. In addition, we demonstrate an HCSFA2 coated microbridge structure and micromechanical photothermal spectroscopy to monitor spectral changes when a vapor sorbs to HCSFA2. Example ATR-FTIR and microbridge spectra with exposures to dimethylmethylphosphonate (DMMP - G nerve agent simulant) and other vapors are compared. In a generic form we illustrate the concept of this work in Figure 1. The results of this work provide the potential to

  15. Oral Streptococci Utilize a Siglec-Like Domain of Serine-Rich Repeat Adhesins to Preferentially Target Platelet Sialoglycans in Human Blood

    PubMed Central

    Deng, Lingquan; Bensing, Barbara A.; Thamadilok, Supaporn; Yu, Hai; Lau, Kam; Chen, Xi; Ruhl, Stefan; Sullam, Paul M.; Varki, Ajit

    2014-01-01

    Damaged cardiac valves attract blood-borne bacteria, and infective endocarditis is often caused by viridans group streptococci. While such bacteria use multiple adhesins to maintain their normal oral commensal state, recognition of platelet sialoglycans provides an intermediary for binding to damaged valvular endocardium. We use a customized sialoglycan microarray to explore the varied binding properties of phylogenetically related serine-rich repeat adhesins, the GspB, Hsa, and SrpA homologs from Streptococcus gordonii and Streptococcus sanguinis species, which belong to a highly conserved family of glycoproteins that contribute to virulence for a broad range of Gram-positive pathogens. Binding profiles of recombinant soluble homologs containing novel sialic acid-recognizing Siglec-like domains correlate well with binding of corresponding whole bacteria to arrays. These bacteria show multiple modes of glycan, protein, or divalent cation-dependent binding to synthetic glycoconjugates and isolated glycoproteins in vitro. However, endogenous asialoglycan-recognizing clearance receptors are known to ensure that only fully sialylated glycans dominate in the endovascular system, wherein we find these particular streptococci become primarily dependent on their Siglec-like adhesins for glycan-mediated recognition events. Remarkably, despite an excess of alternate sialoglycan ligands in cellular and soluble blood components, these adhesins selectively target intact bacteria to sialylated ligands on platelets, within human whole blood. These preferred interactions are inhibited by corresponding recombinant soluble adhesins, which also preferentially recognize platelets. Our data indicate that circulating platelets may act as inadvertent Trojan horse carriers of oral streptococci to the site of damaged endocardium, and provide an explanation why it is that among innumerable microbes that gain occasional access to the bloodstream, certain viridans group streptococci have a

  16. Vacuum application of thermal barrier plasma coatings

    NASA Technical Reports Server (NTRS)

    Holmes, R. R.; Mckechnie, T. N.

    1988-01-01

    Coatings are presently applied to Space Shuttle Main Engine (SSME) turbine blades for protection against the harsh environment realized in the engine during lift off-to-orbit. High performance nickel, chromium, aluminum, and yttrium (NiCrAlY) alloy coatings, which are applied by atmospheric plasma spraying, crack and spall off because of the severe thermal shock experienced during start-up and shut-down of the engine. Ceramic coatings of yttria stabilized zirconia (ZrO2-Y2O3) were applied initially as a thermal barrier over coating to the NiCrAlY but were removed because of even greater spalling. Utilizing a vacuum plasma spraying process, bond coatings of NiCrAlY were applied in a low pressure atmosphere of argon/helium, producing significantly improved coating-to-blade bonding. The improved coatings showed no spalling after 40 MSFC burner rig thermal shock cycles, cycling between 1700 and -423 F. The current atmospheric plasma NiCrAlY coatings spalled during 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2-Y2O3 to the turbine blades of first stage high-pressure fuel turbopumps utilizing the vacuum plasma process. The improved thermal barrier coating has successfully passed 40 burner rig thermal shock cycles without spalling. Hot firing in an SSME turbine engine is scheduled for the blades. Tooling was installed in preparation for vacuum plasma spray coating other SSME hardware, e.g., the titanium main fuel valve housing (MFVH) and the fuel turbopump nozzle/stator.

  17. NICKEL COATED URANIUM ARTICLE

    DOEpatents

    Gray, A.G.

    1958-10-01

    Nickel coatings on uranium and various methods of obtaining such coatings are described. Specifically disclosed are such nickel or nickel alloy layers as barriers between uranium and aluminum- silicon, chromium, or copper coatings.

  18. Corrosion resistant coating

    DOEpatents

    Wrobleski, Debra A.; Benicewicz, Brian C.; Thompson, Karen G.; Bryan, Coleman J.

    1997-01-01

    A method of protecting a metal substrate from corrosion including coating a metal substrate of, e.g., steel, iron or aluminum, with a conductive polymer layer of, e.g., polyaniline, coating upon said metal substrate, and coating the conductive polymer-coated metal substrate with a layer of a topcoat upon the conductive polymer coating layer, is provided, together with the resultant coated article from said method.

  19. Corrosion resistant coating

    DOEpatents

    Wrobleski, D.A.; Benicewicz, B.C.; Thompson, K.G.; Bryan, C.J.

    1997-08-19

    A method of protecting a metal substrate from corrosion including coating a metal substrate of, e.g., steel, iron or aluminum, with a conductive polymer layer of, e.g., polyaniline, coating upon said metal substrate, and coating the conductive polymer-coated metal substrate with a layer of a topcoat upon the conductive polymer coating layer, is provided, together with the resultant coated article from said method.

  20. The Chemistry of Coatings.

    ERIC Educational Resources Information Center

    Griffith, James R.

    1981-01-01

    The properties of natural and synthetic polymeric "coatings" are reviewed, including examples and uses of such coatings as cellulose nitrate lacquers (for automobile paints), polyethylene, and others. (JN)

  1. The Chemistry of Coatings.

    ERIC Educational Resources Information Center

    Griffith, James R.

    1981-01-01

    The properties of natural and synthetic polymeric "coatings" are reviewed, including examples and uses of such coatings as cellulose nitrate lacquers (for automobile paints), polyethylene, and others. (JN)

  2. Coatings for rubber bonding and paint adhesion

    NASA Astrophysics Data System (ADS)

    Boulos, M. S.; Petschel, M.

    1997-08-01

    Conversion coatings form an important base for the adhesion of paint to metal substrates and for the bonding of rubber to metal parts. Four types of conversion coatings were assessed as base treatments for the bonding of rubber to steel and for the corrosion protection of metal substrates under paint: amorphous iron phosphate, heavy zinc phosphate, and three types of modified zinc phosphates that utilized one or more metal cations in addition to zinc. When applied, these conversion coatings formed a thin film over the metal substrate that was characterized by scanning electron microscopy, x-ray diffraction, and chemical methods. The performance of the coatings was assessed using physical methods such as dry adhesion, conical mandrel, impact, and stress adhesion for the rubber-bonded parts, and by corrosion resistance methods such as humidity, salt spray, and cyclic corrosion. Coating characterization and performance were correlated.

  3. Simulation of magnetic coatings on textile fibers

    NASA Astrophysics Data System (ADS)

    Blachowicz, T.; Ehrmann, A.

    2016-08-01

    While the properties of conductive fibres and coatings on textiles can easily be measured and calculated, magnetic coatings of fibres, yarns and fabrics still lack descriptions of their physical properties. Since magnetic textiles can be used for a variety of applications, from magnetic filters to invisible water-marks to magnetic coils and sensors, simulations would be supportive to understand and utilize their properties. The article gives an overview of different coatings on textile fibres, varying the magnetic materials as well as the fibre composition, giving rise to the interactions between neighbouring coated fibres. In this way, it is possible to understand the strong shape anisotropy which must be taken into account when the magnetic properties of textiles are to be tailored. Additionally, the differences between several possible magnetic coating materials become visible. This study can help adjusting the magnetic properties of textile fabrics to a desired application.

  4. Thermal barrier coating evaluation needs

    NASA Technical Reports Server (NTRS)

    Brindley, William J.; Miller, Robert A.

    1990-01-01

    A 0.025 cm (0.010 in) thick thermal barrier coating (TBC) applied to turbine airfoils in a research gas turbine engine provided component temperature reductions of up to 190 C. These impressive temperature reductions can allow increased engine operating temperatures and reduced component cooling to achieve greater engine performance without sacrificing component durability. The significant benefits of TBCs are well established in aircraft gas turbine engine applications and their use is increasing. TBCs are also under intense development for use in the Low Heat Rejection (LHR) diesel engine currently being developed and are under consideration for use in utility and marine gas turbines. However, to fully utilize the benefits of TBCs it is necessary to accurately characterize coating attributes that affect the insulation and coating durability. The purpose there is to discuss areas in which nondestructive evaluation can make significant contributions to the further development and full utilization of TBCs for aircraft gas turbine engines and low heat rejection diesel engines.

  5. Advanced Coats' disease.

    PubMed Central

    Haik, B G

    1991-01-01

    Advanced Coats' disease and retinoblastoma can both present with the triad of a retinal detachment, the appearance of a subretinal mass, and dilated retinal vessels. Thus, even the most experienced observer may not be able to differentiate these entities on ophthalmoscopic findings alone. Coats' disease is the most common reason for which eyes are enucleated with the misdiagnosis of retinoblastoma. Ultrasonography is the auxiliary diagnostic test most easily incorporated into the clinical examination, and can be utilized repeatedly without biologic tissue hazard. Ultrasonically identifiable features allowing differentiation between Coats' disease and retinoblastoma include the topography and character of retinal detachment and presence or absence of subretinal calcifications. Ultrasonography is of lesser use in poorly calcified retinoblastoma and in detecting optic nerve or extraocular extension in heavily calcified retinoblastoma. CT is perhaps the single most valuable test because of its ability to: (a) delineate intraocular morphology, (b) quantify subretinal densities, (c) identify vascularities within the subretinal space through the use of contrast enhancement, and (d) detected associated orbital or intracranial abnormalities. Optimal computed tomographic studies, however, require multiple thin slices both before and after contrast introduction and expose the child to low levels of radiation if studies are repeated periodically. MR imaging is valuable for its multiplanar imaging capabilities, its superior contrast resolution, and its ability to provide insights into the biochemical structure and composition of tissues. It is limited in its ability to detect calcium, which is the mainstay of ultrasonic and CT differentiation. Aqueous LDH and isoenzyme levels were not valuable in distinguishing between Coats' disease and retinoblastoma. The value of aqueous NSE levels in the differentiation of advanced Coats' disease and exophytic retinoblastoma deserves

  6. Electrocurtain coating process for coating solar mirrors

    SciTech Connect

    Kabagambe, Benjamin; Boyd, Donald W.; Buchanan, Michael J.; Kelly, Patrick; Kutilek, Luke A.; McCamy, James W.; McPheron, Douglas A.; Orosz, Gary R.; Limbacher, Raymond D.

    2013-10-15

    An electrically conductive protective coating or film is provided over the surface of a reflective coating of a solar mirror by flowing or directing a cation containing liquid and an anion containing liquid onto the conductive surface. The cation and the anion containing liquids are spaced from, and preferably out of contact with one another on the surface of the reflective coating as an electric current is moved through the anion containing liquid, the conductive surface between the liquids and the cation containing liquid to coat the conductive surface with the electrically conductive coating.

  7. Effect of metal coatings on mechanical properties of aluminium alloy

    NASA Astrophysics Data System (ADS)

    Ravi Kumar, V.; Dileep, B. P.; Mohan Kumar, S.; Phanibhushana, M. V.

    2017-07-01

    This investigation mainly targeted on study of hardness and tensile properties of Al 7075 with different metal coatings like Nickel, Zinc and cadmium. Coating of these metals on Al 7075 is successfully achieved by time dependent electroplating method for different thicknesses of 10, 15 and 20 Microns. These metal coated Al-7075 specimens were tested for hardness and tensile properties according to the ASTM standards. It's found that Nickel coated alloy shows excellent hardness and tensile properties compared to Zinc and Cadmium coated alloys. 20 µm Nickel coated alloy exhibits highest hardness number of 102 HRB and Maximum Tensile Strength of 603 MPa than Zinc and Cadmium coated alloy. The microstructural studies authenticated that the coating of Nickel, zinc and cadmium on Al 7075 is homogeneous.

  8. Tribological performance of hybrid filtered arc-magnetron coatings - Part I: Coating deposition process and basic coating properties characterization

    SciTech Connect

    Gorokhovsky, Vladimir; Bowman, C.; Gannon, Paul E.; VanVorous, D.; Voevodin, A. A.; Rutkowski, A.; Muratore, C.; Smith, Richard J.; Kayani, Asghar N.; Gelles, David S.; Shutthanandan, V.; Trusov, B. G.

    2006-12-04

    Aircraft propulsion applications require low-friction and wear resistant surfaces that operate under high contact loads in severe environments. Recent research on supertough and low friction nanocomposite coatings produced with hybrid plasma deposition processes was demonstrated to have a high potential for such demanding applications. However, industrially scalable hybrid plasma technologies are needed for their commercial realization. The Large area Filtered Arc Deposition (LAFAD) process provides atomically smooth coatings at high deposition rates over large surface areas. The LAFAD technology allows functionally graded, multilayer, super-lattice and nanocomposite architectures of multi-elemental coatings via electro-magnetic mixing of two plasma flows composed of different metal ion vapors. Further advancement can be realized through a combinatorial process using a hybrid filtered arc-magnetron deposition system. In the present study, multilayer and nanostructured TiCrCN/TiCr +TiBC composite cermet coatings were deposited by the hybrid filtered arc-magnetron process. Filtered plasma streams from arc evaporated Ti and Cr targets, and two unbalanced magnetron sputtered B4C targets, were directed to the substrates in the presence of reactive gases. A multiphase nanocomposite coating architecture was designed to provide the optimal combination of corrosion and wear resistance of advanced steels (Pyrowear 675) used in aerospace bearing and gear applications. Coatings were characterized using SEM/EDS, XPS and RBS for morphology and chemistry, XRD and TEM for structural analyses, wafer curvature and nanoindentation for stress and mechanical properties, and Rockwell and scratch indentions for adhesion. Coating properties were evaluated for a variety of coating architectures. Thermodynamic modeling was used for estimation of phase composition of the top TiBC coating segment. Correlations between coating chemistry, structure and mechanical properties are discussed.

  9. Utilization management in microbiology.

    PubMed

    Branda, John A; Lewandrowski, Kent

    2014-01-01

    The available literature concerning utilization management in the clinical microbiology laboratory is relatively limited compared with that for high-volume, automated testing in the central Core Laboratory. However, the same strategies employed elsewhere in the clinical laboratory operation can be applied to utilization management challenges in microbiology, including decision support systems, application of evidence-based medicine, screening algorithms and gatekeeper functions. The results of testing in the microbiology laboratory have significant effects on the cost of clinical care, especially costs related to antimicrobial agents and infection control practices. Consequently many of the successful utilization management interventions described in clinical microbiology have targeted not just the volume of tests performed in the laboratory, but also the downstream costs of care. This article will review utilization management strategies in clinical microbiology, including specific examples from our institution and other healthcare organizations.

  10. Molecularly-Targeted Gold-Based Nanoparticles for Cancer Imaging and Near-Infrared Photothermal Therapy

    NASA Astrophysics Data System (ADS)

    Day, Emily Shannon

    2011-12-01

    This thesis advances the use of nanoparticles as multifunctional agents for molecularly-targeted cancer imaging and photothermal therapy. Cancer mortality has remained relatively unchanged for several decades, indicating a significant need for improvements in care. Researchers are evaluating strategies incorporating nanoparticles as exogenous energy absorbers to deliver heat capable of inducing cell death selectively to tumors, sparing normal tissue. Molecular targeting of nanoparticles is predicted to improve photothermal therapy by enhancing tumor retention. This hypothesis is evaluated with two types of nanoparticles. The nanoparticles utilized, silica-gold nanoshells and gold-gold sulfide nanoparticles, can convert light energy into heat to damage cancerous cells. For in vivo applications nanoparticles are usually coated with poly(ethylene glycol) (PEG) to increase blood circulation time. Here, heterobifunctional PEG links nanoparticles to targeting agents (antibodies and growth factors) to provide cell-specific binding. This approach is evaluated through a series of experiments. In vitro, antibody-coated nanoparticles can bind breast carcinoma cells expressing the targeted receptor and act as contrast agents for multiphoton microscopy prior to inducing cell death via photoablation. Furthermore, antibody-coated nanoparticles can bind tissue ex vivo at levels corresponding to receptor expression, suggesting they should bind their target even in the complex biological milieu. This is evaluated by comparing the accumulation of antibody-coated and PEG-coated nanoparticles in subcutaneous glioma tumors in mice. Contrary to expectations, antibody targeting did not yield more nanoparticles within tumors. Nevertheless, these studies established the sensitivity of glioma to photothermal therapy; mice treated with PEG-coated nanoshells experienced 57% complete tumor regression versus no regression in control mice. Subsequent experiments employed intracranial tumors to

  11. Multi-layer coatings

    DOEpatents

    Maghsoodi, Sina; Brophy, Brenor L.; Abrams, Ze'ev R.; Gonsalves, Peter R.

    2016-06-28

    Disclosed herein are coating materials and methods for applying a top-layer coating that is durable, abrasion resistant, highly transparent, hydrophobic, low-friction, moisture-sealing, anti-soiling, and self-cleaning to an existing conventional high temperature anti-reflective coating. The top coat imparts superior durability performance and new properties to the under-laying conventional high temperature anti-reflective coating without reducing the anti-reflectiveness of the coating. Methods and data for optimizing the relative thickness of the under-layer high temperature anti-reflective coating and the top-layer thickness for optimizing optical performance are also disclosed.

  12. Beyond Utility Targeting: Toward Axiological Air Operations

    DTIC Science & Technology

    2000-01-01

    resident in an object. The philosopher Risieri Frondizi describes value and values as follows: It would be more appropriate to assert that val­...returns to scale, the value function is con- vex. 8. Risieri Frondizi , What Is Value? trans. Solomon Lipp (LaSalle, Ill.: Open Court, 1963), 6–7. 9

  13. Moving Target Detector Data Utilization Investigation.

    DTIC Science & Technology

    1980-03-01

    the substantial informational content of the M primitive reports provides an effective tecnique for reducing tracker loads, discriminatingi between...to reduce the land clutter returns to manageable proportions and two additional pulses were added to the processing interval to fill the delays of the

  14. Polarization Utilization in Radar Target Reconstruction

    DTIC Science & Technology

    1981-01-15

    Arbor, MI 48107 Dr. Dick Doviak Chief, Advance Techniques National Severe Storms Laboratory 1313 Halley Circle Norman, OK 73069 Dr. Adrian K. Fung...Department of Electrical Engineering University of Kansas Lawrence, KS 66045 Dr. Edmond Gillespie, Chairman Electrical and CQmputer Engineering Dept

  15. Nanosilica coating for bonding improvements to zirconia

    PubMed Central

    Chen, Chen; Chen, Gang; Xie, Haifeng; Dai, Wenyong; Zhang, Feimin

    2013-01-01

    Resin bonding to zirconia cannot be established from standard methods that are currently utilized in conventional silica-based dental ceramics. The solution–gelatin (sol–gel) process is a well developed silica-coating technique used to modify the surface of nonsilica-based ceramics. Here, we use this technique to improve resin bonding to zirconia, which we compared to zirconia surfaces treated with alumina sandblasting and tribochemical silica coating. We used the shear bond strength test to examine the effect of the various coatings on the short-term resin bonding of zirconia. Furthermore, we employed field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, and Fourier transform infrared spectroscopy to characterize the zirconia surfaces. Water–mist spraying was used to evaluate the durability of the coatings. To evaluate the biological safety of the experimental sol–gel silica coating, we conducted an in vitro Salmonella typhimurium reverse mutation assay (Ames mutagenicity test), cytotoxicity tests, and in vivo oral mucous membrane irritation tests. When compared to the conventional tribochemical silica coating, the experimental sol–gel silica coating provided the same shear bond strength, higher silicon contents, and better durability. Moreover, we observed no apparent mutagenicity, cytotoxicity, or irritation in this study. Therefore, the sol–gel technique represents a promising method for producing silica coatings on zirconia. PMID:24179333

  16. Thermal coatings for titanium-aluminum alloys

    NASA Technical Reports Server (NTRS)

    Cunnington, George R.; Clark, Ronald K.; Robinson, John C.

    1993-01-01

    Titanium aluminides and titanium alloys are candidate materials for use in hot structure and heat-shield components of hypersonic vehicles because of their good strength-to-weight characteristics at elevated temperature. However, in order to utilize their maximum temperature capability, they must be coated to resist oxidation and to have a high total remittance. Also, surface catalysis for recombination of dissociated species in the aerodynamic boundary layer must be minimized. Very thin chemical vapor deposition (CVD) coatings are attractive candidates for this application because of durability and very light weight. To demonstrate this concept, coatings of boron-silicon and aluminum-boron-silicon compositions were applied to the titanium-aluminides alpha2 (Ti-14Al-21Nb), super-alpha2 (Ti-14Al-23-Nb-2V), and gamma (Ti-33Al-6Nb-1Ta) and to the titanium alloy beta-21S (Ti-15Mo-3Al-3Nb-0.2Si). Coated specimens of each alloy were subjected to a set of simulated hypersonic vehicle environmental tests to determine their properties of oxidation resistance, surface catalysis, radiative emittance, and thermal shock resistance. Surface catalysis results should be viewed as relative performance only of the several coating-alloy combinations tested under the specific environmental conditions of the LaRC Hypersonic Materials Environmental Test System (HYMETS) arc-plasma-heated hypersonic wind tunnel. Tests were also conducted to evaluate the hydrogen transport properties of the coatings and any effects of the coating processing itself on fatigue life of the base alloys. Results are presented for three types of coatings, which are as follows: (1) a single layer boron silicon coating, (2) a single layer aluminum-boron-silicon coating, and (3) a multilayer coating consisting of an aluminum-boron-silicon sublayer with a boron-silicon outer layer.

  17. Functionally graded mullite coatings for gas turbines

    NASA Astrophysics Data System (ADS)

    Kulkarni, Tushar

    The next generation of heat exchangers and gas turbines require high performance materials as they need to operate at higher temperatures for higher efficiency. SiC and Si3N4 are promising candidates as they have excellent high temperature properties. However, when used in complex combustion environments found in gas-turbine applications, these materials have two major concerns; namely hot-corrosion and recession. It is well established that environmental barrier coatings (EBC) can be utilized to overcome these limitations. Although chemical vapor deposited (CVD) mullite (3Al2O 3.2SiO2) coatings developed before this study have shown promise in protecting Si-based substrates, there is concern that the silica content within the mullite coating itself might be susceptible to hot-corrosion and recession during long term exposure to corrosive atmospheres containing Na/V salts and water vapor. There is thus strong motivation to substantially reduce or even virtually eliminate the silica component from the surfaces of mullite coatings that are in direct contact with atmospheres containing corrosive oxides and steam. In this study, CVD has been used to deposit mullite coatings with potential promise to protect Si-based ceramics for high temperature applications. The composition of these functionally graded mullite coatings was varied from silica-rich close to the coating/substrate (SiC) interface for coefficient of thermal expansion match to alumina-rich towards the outer surface of the coating. In the process, the highest alumina-rich mullite ever reported has been deposited. The phase transformation and hot-corrosion behavior of the coatings was also investigated in this work. The coatings show immense potential to protect Si-based ceramics. It is expected that these coatings will have very broad impact by enabling gas turbines to operate at higher temperatures leading to improved fuel efficiency and reduced emissions.

  18. Sputtered silicon nitride coatings for wear protection

    NASA Technical Reports Server (NTRS)

    Grill, A.; Aron, P. R.

    1982-01-01

    Silicon nitride films were deposited by RF sputtering on 304 stainless steel substrates in a planar RF sputtering apparatus. The sputtering was performed from a Si3N4 target in a sputtering atmosphere of argon and nitrogen. The rate of deposition, the composition of the coatings, the surface microhardness and the adhesion of the coatings to the substrates were investigated as a function of the process parameters, such as: substrate target distance, fraction nitrogen in the sputtering atmosphere and sputtering pressure. Silicon rich coating was obtained for fraction nitrogen below 0.2. The rate of deposition decreases continuously with increasing fraction nitrogen and decreasing sputtering pressure. It was found that the adherence of the coatings improves with decreasing sputtering pressure, almost independently of their composition.

  19. Enhanced ELISA using a handheld pH meter and enzyme-coated microparticles for the portable, sensitive detection of proteins.

    PubMed

    Zhang, Yun; Yang, Jiani; Nie, Jinfang; Yang, Juanhua; Gao, Dong; Zhang, Lang; Li, Jianping

    2016-02-28

    This work describes a general methodology for enhanced enzyme-linked immunosorbent assay (ELISA) that integrates enzyme-coated microparticle probes for robust yet highly efficient signal amplification and a handheld pH meter for a simple, portable, quantitative readout. Its utility is well demonstrated with the detection of the target protein with a 14-fold enhancement of sensitivity in comparison with the conventional optical ELISA.

  20. Sodium-Doped Molybdenum Targets for Controllable Sodium Incorporation in CIGS Solar Cells: Preprint

    SciTech Connect

    Mansfield, L. M.; Repins, I. L.; Glynn, S.; Carducci, M. D.; Honecker, D. M.; Pankow, J.; Young, M.; DeHart, C.; Sundaramoorthy, R.; Beall, C. L.; To, B.

    2011-07-01

    The efficiency of Cu(In,Ga)Se2 (CIGS) solar cells is enhanced when Na is incorporated in the CIGS absorber layer. This work examines Na incorporation in CIGS utilizing Na-doped Mo sputtered from targets made with sodium molybdate-doped (MONA) powder. Mo:Na films with varying thicknesses were sputtered onto Mo-coated borosilicate glass (BSG) or stainless steel substrates for CIGS solar cells. By use of this technique, the Na content of CIGS can be varied from near-zero to higher than that obtained from a soda-lime glass (SLG) substrate. Targets and deposition conditions are described. The doped Mo films are analyzed, and the resulting devices are compared to devices fabricated on Mo-coated SLG as well as Mo-coated BSG with NaF. Completed devices utilizing MONA exceeded 15.7% efficiency without anti-reflective coating, which was consistently higher than devices prepared with the NaF precursor. Strategies for minimizing adhesion difficulties are presented.

  1. Sodium-Doped Molybdenum Targets for Controllable Sodium Incorporation in CIGS Solar Cells

    SciTech Connect

    Mansfield, L. M.; Repins, I. L.; Glynn, S.; Carducci, M. D.; Honecker, D. M.; Pankow, J.l W.; Young, M. R.; DeHart, C.; Sundaramoorthy, R.; Beall, C. L.; To, B.

    2011-01-01

    The efficiency of Cu(In, Ga)Se{sub 2} (CIGS) solar cells is enhanced when Na is incorporated in the CIGS absorber layer. This work examines Na incorporation in CIGS utilizing Na-doped Mo sputtered from targets made with sodium molybdate-doped (MONA) powder. Mo:Na films with varying thicknesses were sputtered onto Mo-coated borosilicate glass (BSG) or stainless steel substrates for CIGS solar cells. By use of this technique, the Na content of CIGS can be varied from near-zero to higher than that obtained from a soda-lime glass (SLG) substrate. Targets and deposition conditions are described. The doped Mo films are analyzed, and the resulting devices are compared to devices fabricated on Mo-coated SLG as well as Mo-coated BSG with NaF. Completed devices utilizing MONA exceeded 15.7% efficiency without anti-reflective coating, which was consistently higher than devices prepared with the NaF precursor. Strategies for minimizing adhesion difficulties are presented.

  2. Oxidation protection coatings for polymers

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Sovey, J. S.; Banks, B. A. (Inventor)

    1985-01-01

    A polymeric substrate is coated with a metal oxide film to provide oxidation protection in low Earth orbital environments. The film contains about 4 volume percent polymer to provide flexibility. A coil of polymer material moves through an ion beam as it is fed between reels. The ion beam first cleans the polymer material surface and then sputters the film material from a target onto this surface.

  3. Thin film coating process using an inductively coupled plasma

    DOEpatents

    Kniseley, Richard N.; Schmidt, Frederick A.; Merkle, Brian D.

    1990-01-30

    Thin coatings of normally solid materials are applied to target substrates using an inductively coupled plasma. Particles of the coating material are vaporized by plasma heating, and pass through an orifice to a first vacuum zone in which the particles are accelerated to a velocity greater than Mach 1. The shock wave generated in the first vacuum zone is intercepted by the tip of a skimmer cone that provides a second orifice. The particles pass through the second orifice into a second zone maintained at a higher vacuum and impinge on the target to form the coating. Ultrapure coatings can be formed.

  4. Multifunctional biocompatible coatings on magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Bychkova, A. V.; Sorokina, O. N.; Rosenfeld, M. A.; Kovarski, A. L.

    2012-11-01

    Methods for coating formation on magnetic nanoparticles used in biology and medicine are considered. Key requirements to the coatings are formulated, namely, biocompatibility, stability, the possibility of attachment of pharmaceutical agents, and the absence of toxicity. The behaviour of nanoparticle/coating nanosystems in the body including penetration through cellular membranes and the excretion rates and routes is analyzed. Parameters characterizing the magnetic properties of these systems and their magnetic controllability are described. Factors limiting the applications of magnetically controlled nanosystems for targeted drug delivery are discussed. The bibliography includes 405 references.

  5. Stability of influenza vaccine coated onto microneedles

    PubMed Central

    Choi, Hyo-Jick; Yoo, Dae-Goon; Bondy, Brian J.; Quan, Fu-Shi; Compans, Richard W.; Kang, Sang-Moo; Prausnitz, Mark R.

    2012-01-01

    A microneedle patch coated with vaccine simplifies vaccination by using a patch-based delivery method and targets vaccination to the skin for superior immunogenicity compared to intramuscular injection. Previous studies of microneedles have demonstrated effective vaccination using freshly prepared microneedles, but the issue of long-term vaccine stability has received only limited attention. Here, we studied the long-term stability of microneedles coated with whole inactivated influenza vaccine guided by the hypothesis that crystallization and phase separation of the microneedle coating matrix damages influenza vaccine coated onto microneedles. In vitro showed that the vaccine lost stability as measured by hemagglutination activity in proportion to the degree of coating matrix crystallization and phase separation. Transmission electron microscopy similarly showed damaged morphology of the inactivated virus vaccine associated with crystallization. In vivo assessment of immune response and protective efficacy in mice further showed reduced vaccine immunogenicity after influenza vaccination using microneedles with crystallized or phase-separated coatings. This work shows that crystallization and phase separation of the dried coating matrix are important factors affecting long-term stability of influenza vaccine-coated microneedles. PMID:22361098

  6. Flow coating apparatus and method of coating

    DOEpatents

    Hanumanthu, Ramasubrahmaniam; Neyman, Patrick; MacDonald, Niles; Brophy, Brenor; Kopczynski, Kevin; Nair, Wood

    2014-03-11

    Disclosed is a flow coating apparatus, comprising a slot that can dispense a coating material in an approximately uniform manner along a distribution blade that increases uniformity by means of surface tension and transfers the uniform flow of coating material onto an inclined substrate such as for example glass, solar panels, windows or part of an electronic display. Also disclosed is a method of flow coating a substrate using the apparatus such that the substrate is positioned correctly relative to the distribution blade, a pre-wetting step is completed where both the blade and substrate are completed wetted with a pre-wet solution prior to dispensing of the coating material onto the distribution blade from the slot and hence onto the substrate. Thereafter the substrate is removed from the distribution blade and allowed to dry, thereby forming a coating.

  7. Thermal and Environmental Barrier Coatings for Advanced Propulsion Engine Systems

    NASA Technical Reports Server (NTRS)

    Zhu, Dong-Ming; Miller, Robert A.

    2004-01-01

    Ceramic thermal and environmental barrier coatings (TEBCs) are used in gas turbine engines to protect engine hot-section components in the harsh combustion environments, and extend component lifetimes. For future high performance engines, the development of advanced ceramic barrier coating systems will allow these coatings to be used to simultaneously increase engine operating temperature and reduce cooling requirements, thereby leading to significant improvements in engine power density and efficiency. In order to meet future engine performance and reliability requirements, the coating systems must be designed with increased high temperature stability, lower thermal conductivity, and improved thermal stress and erosion resistance. In this paper, ceramic coating design and testing considerations will be described for high temperature and high-heat-flux engine applications in hot corrosion and oxidation, erosion, and combustion water vapor environments. Further coating performance and life improvements will be expected by utilizing advanced coating architecture design, composition optimization, and improved processing techniques, in conjunction with modeling and design tools.

  8. Apparatus for coating powders

    DOEpatents

    Makowiecki, Daniel M.; Kerns, John A.; Alford, Craig S.; McKernan, Mark A.

    2000-01-01

    A process and apparatus for coating small particles and fibers. The process involves agitation by vibrating or tumbling the particles or fibers to promote coating uniformly, removing adsorbed gases and static charges from the particles or fibers by an initial plasma cleaning, and coating the particles or fibers with one or more coatings, a first coating being an adhesion coating, and with subsequent coatings being deposited in-situ to prevent contamination at layer interfaces. The first coating is of an adhesion forming element (i.e. W, Zr, Re, Cr, Ti) of a 100-10,000 .ANG. thickness and the second coating or final coating of a multiple (0.1-10 microns) being Cu or Ag, for example for brazing processes, or other desired materials that defines the new surface related properties of the particles. An essential feature of the coating process is the capability to deposit in-situ without interruption to prevent the formation of a contaminated interface that could adversely affect the coating adhesion. The process may include screening of the material to be coated and either continuous or intermittent vibration to prevent agglomeration of the material to be coated.

  9. BdCESA7, BdCESA8, and BdPMT utility promoter constructs for targeted expression to secondary cell-wall-forming cells of grasses

    SciTech Connect

    Petrik, Deborah L.; Cass, Cynthia L.; Padmakshan, Dharshana; Foster, Cliff E.; Vogel, John P.; Karlen, Steven D.; Ralph, John; Sedbrook, John C.

    2016-02-04

    Utility vectors with promoters that confer desired spatial and temporal expression patterns are useful tools for studying gene and cellular function and for industrial applications. To target the expression of DNA sequences of interest to cells forming plant secondary cell walls, which generate most of the vegetative biomass, upstream regulatory sequences of the Brachypodium distachyon lignin biosynthetic gene BdPMT and the cellulose synthase genes BdCESA7 and BdCESA8 were isolated and cloned into binary vectors designed for Agrobacterium-mediated transformation of monocots. Expression patterns were assessed using the β-glucuronidase gene GUSPlus and X-glucuronide staining. All three promoters showed strong expression levels in stem tissue at the base of internodes where cell wall deposition is most active, in both vascular bundle xylem vessels and tracheids, and in interfascicular tissues, with expression less pronounced in developmentally older tissues. In leaves, BdCESA7 and BdCESA8 promoter-driven expression was strongest in leaf veins, leaf margins, and trichomes; relatively weaker and patchy expression was observed in the epidermis. BdPMT promoter-driven expression was similar to the BdCESA promoters expression patterns, including strong expression in trichomes. The intensity and extent of GUS staining varied considerably between transgenic lines, suggesting that positional effects influenced promoter activity. Introducing the BdPMT and BdCESA8 Open Reading Frames into BdPMT and BdCESA8 utility promoter binary vectors, respectively, and transforming those constructs into Brachypodium pmt and cesa8 loss-of-function mutants resulted in rescue of the corresponding mutant phenotypes. This work therefore validates the functionality of these utility promoter binary vectors for use in Brachypodium and likely other grass species. Lastly, the identification

  10. Refractory coatings

    NASA Technical Reports Server (NTRS)

    Brainard, W. A.; Wheeler, D. R. (Inventor)

    1982-01-01

    A thin sputtered film is discussed which exhibits improved adherence to a substrate and has improved friction and wear characteristics. Each substrate is placed directly below a titanium carbide target of a commercial radiofrequency diode apparatus in a vacuum chamber. Nitrogen is bled into the system through a nozzle resulting in a small partial pressure of about 0.5% to 2.5% during the first two minutes of deposition. The flow of nitrogen is then stopped, and the sputtering ambient is reduced to pure argon through a nozzle without interrupting the sputtering process.

  11. Thin film thermoelectric devices as thermal control coatings: A study

    NASA Technical Reports Server (NTRS)

    Clemons, J. M.; Krupnick, A. C.

    1973-01-01

    Peltier effect, Thomson effect, and Seeback effect are utilized in design of thermal control coating that serves as versatile means for controlling heat absorbed and radiated by surface. Coatings may be useful in extreme temperature environment enclosures or as heat shields.

  12. Lighting Utilization.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with lighting utilization. Its objective is for the student to be able to outline the development of lighting use and conservation and identify major types and operating characteristics of lamps used in electric lighting. Some topics…

  13. Optimizing High-Z Coatings for Inertial Fusion Energy Shells

    SciTech Connect

    Stephens, Elizabeth H.; Nikroo, Abbas; Goodin, Daniel T.; Petzoldt, Ronald W.

    2003-05-15

    Inertial fusion energy (IFE) reactors require shells with a high-Z coating that is both permeable, for timely filling with deuterium-tritium, and reflective, for survival in the chamber. Previously, gold was deposited on shells while they were agitated to obtain uniform, reproducible coatings. However, these coatings were rather impermeable, resulting in unacceptably long fill times. We report here on an initial study on Pd coatings on shells in the same manner. We have found that these palladium-coated shells are substantially more permeable than gold. Pd coatings on shells remained stable on exposure to deuterium. Pd coatings had lower reflectivity compared to gold that leads to a lower working temperature, and efficiency, of the proposed fusion reactor. Seeking to combine the permeability of Pd coatings and high reflectivity of gold, AuPd-alloy coatings were produced using a cosputtering technique. These alloys demonstrated higher permeability than Au and higher reflectivity than Pd. However, these coatings were still less reflective than the gold coatings. To improve the permeability of gold's coatings, permeation experiments were performed at higher temperatures. With the parameters of composition, thickness, and temperature, we have the ability to comply with a large target design window.

  14. Conformal coatings : challenging environments lead to growth.

    SciTech Connect

    Challener, Cynthia A.

    2005-08-01

    Advances in technology have resulted in the need for electronic devices to continue functioning even when placed in harsh environments. Widespread use of cell phones, laptop computers, and other personal electronic devices, the increased number of electronic controls in home appliances, and the ever more extensive utilization of digital technology in the automotive industry have led to a growing demand for printed circuit boards (PCBs) that can perform under difficult conditions. Conformal coatings provide a protective barrier that enables the PCBs to function in these demanding environments. This growth in demand comes despite the cost and numerous difficulties associated with the application of these coatings. Many conformal coatings manufacturers are investing in the development of new technologies that minimize these difficulties. Others are involved in developing disruptive technologies that will serve as alternatives to traditional conformal coatings processes.

  15. Thermoplastic coating of carbon fibers

    NASA Technical Reports Server (NTRS)

    Edie, D. D.; Lickfield, G. C.

    1991-01-01

    Using a continuous powder coating process, more than 1500 meters of T 300/LaRC-TPI prepreg were produced. Two different types of heating sections in the coating line, namely electrical resistance and convection heating, were utilized. These prepregs were used to fabricate unidirectional composites. During co