2,775 research outputs found

    The Peptide/Antibody-Based Surface Decoration of Calcium Phosphate Nanoparticles Carrying siRNA Influences the p65 NF-ÎșB Protein Expression in Inflamed Cells In Vitro

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    Earlier studies with nanoparticles carrying siRNA were restricted to investigating the inhibition of target-specific protein expression, while almost ignoring effects related to the nanoparticle composition. Here, we demonstrate how the design and surface decoration of nanoparticles impact the p65 nuclear factor-kappa B (NF-ÎșB) protein expression in inflamed leucocytes and endothelial cells in vitro. We prepared silica-coated calcium phosphate nanoparticles carrying encapsulated siRNA against p65 NF-ÎșB and surface-decorated with peptides or antibodies. We show that RGD-decorated nanoparticles are efficient in down-regulating p65 NF-ÎșB protein expression in endothelial cells as a result of an enhanced specific cellular binding and subsequent uptake of nanoparticles. In contrast, nanoparticles decorated with IgG (whether specific or not for CD69) are efficient in down-regulating p65 NF-ÎșB protein expression in T-cells, but not in B-cells. Thus, an optimized nanoparticle decoration with xenogenic IgG may stimulate a specific cellular uptake. In summary, the composition of siRNA-loaded calcium phosphate nanoparticles can either weaken or stimulate p65 NF-ÎșB protein expression in targeted inflamed leucocytes and endothelial cells. In general, unveiling such interactions may be very useful for the future design of anti-p65 siRNA-based nanomedicines for treatment of inflammation-associated diseases

    Synthesis of positively and negatively charged silver nanoparticles and their deposition on the surface of titanium

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    Bacterial infections related to dental implants are currently a significant complication. A good way to overcome this challenge is functionalization of implant surface with Ag nanoparticles (NPs) as antibacterial agent. This article aims at review the synthesis routes, size and electrical properties of AgNPs. Polyvinyl pyrrolidone (PVP) and polyethyleneimine (PEI) were used as stabilizers. Dynamic Light Scattering, Nanoparticle Tracking Analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDX) have been used to characterize the prepared AgNPs. Two types of NPs were synthesized in aqueous solutions: PVP-stabilized NPs with a diameter of the metallic core of 70 ± 20 nm, and negative charge of -20 mV, PEI-stabilized NPs with the size of the metallic core of 50 ± 20 nm and positive charge of +55 mV. According to SEM results, all the NPs have a spherical shape. Functionalization of the titanium substrate surface with PVP and PEI-stabilized AgNPs was carried out by dropping method. XRD patterns revealed that the AgNPs are crystalline with the crystallite size of 14 nm

    Dataset of coded handwriting features for use in statistical modelling

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    © 2017 The Authors The data presented here is related to the article titled, “Using handwriting to infer a writer's country of origin for forensic intelligence purposes” (Agius et al., 2017) [1]. This article reports original writer, spatial and construction characteristic data for thirty-seven English Australian1 writers and thirty-seven Vietnamese writers. All of these characteristics were coded and recorded in Microsoft Excel 2013 (version 15.31). The construction characteristics coded were only extracted from seven characters, which were: ‘g’ ‘h’ ‘th’ ‘M’ ‘0’ ‘7’ and ‘9’. The coded format of the writer, spatial and construction characteristics is made available in this Data in Brief in order to allow others to perform statistical analyses and modelling to investigate whether there is a relationship between the handwriting features and the nationality of the writer, and whether the two nationalities can be differentiated. Furthermore, to employ mathematical techniques that are capable of characterising the extracted features from each participant

    Electromagnetic Calorimeter for HADES

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    We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV. A purity of the identified leptons after the hadron rejection, resulting from simulations based on the test measurements, is better than 80% at momenta above 500 MeV/c, where time-of-flight cannot be used.Comment: 40 pages, 38 figures version2 - the time schedule added, information about PMTs in Sec.III update

    String Loop Corrections to Kahler Potentials in Orientifolds

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    We determine one-loop string corrections to Kahler potentials in type IIB orientifold compactifications with either N=1 or N=2 supersymmetry, including D-brane moduli, by evaluating string scattering amplitudes.Comment: 80 pages, 4 figure

    Neutrophils self-limit swarming to contain bacterial growth in vivo

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    Neutrophils communicate with each other to form swarms in infected organs. Coordination of this population response is critical for the elimination of bacteria and fungi. Using transgenic mice, we found that neutrophils have evolved an intrinsic mechanism to self-limit swarming and avoid uncontrolled aggregation during inflammation. G protein–coupled receptor (GPCR) desensitization acts as a negative feedback control to stop migration of neutrophils when they sense high concentrations of self-secreted attractants that initially amplify swarming. Interference with this process allows neutrophils to scan larger tissue areas for microbes. Unexpectedly, this does not benefit bacterial clearance as containment of proliferating bacteria by neutrophil clusters becomes impeded. Our data reveal how autosignaling stops self-organized swarming behavior and how the finely tuned balance of neutrophil chemotaxis and arrest counteracts bacterial escape

    Higher Dimensional Recombination of Intersecting D-branes

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    We study recombinations of D-brane systems intersecting at more than one angle using super Yang-Mills theory. We find the condensation of an off-diagonal tachyon mode relates to the recombination, as was clarified for branes at one angle in hep-th/0303204. For branes at two angles, after the tachyon mode between two D2-branes condensed, D2-brane charge is distributed in the bulk near the intersection point. We also find that, when two intersection angles are equal, the off-diagonal lowest mode is massless, and a new stable non-abelian configuration, which is supersymmetric up to a quadratic order in the fluctuations, is obtained by the deformation by this mode.Comment: 18 pages, 2 figures, JHEP style. v3:references added, minor corrections, English improve

    Carboxylic trifluoromethanesulfonic and methanesulfonic anhydrides, synthesis and dissociation tendency

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    CarbonsĂ€ure-trifluormethansulfonsĂ€ure-anhydride 3 und -methansulfonsĂ€ure-anhydride 7 sind aus den entsprechenden CarbonsĂ€urechloriden 1 mit Silber-trifluormethansulfonat (2) bzw. Silber-methansulfonat (6) in guten Ausbeuten zugĂ€nglich; die Anhydride 3 können auch aus den Chloriden 1 mit TrifluormethansulfonsĂ€ure (4) hergestellt werden. Die schon in 1,2-Dichlorethan zu beobachtende Dissoziation der Anhydride 3 in AbhĂ€ngigkeit von elektronischen und sterischen Faktoren wurde quantitativ bestimmt. Die Dissoziationskonstanten der 4-substituierten 2,6-DimethylbenzoesĂ€ure-trifluormethansulfonsĂ€ure-anhydride 3k-o korrelieren zufriedenstellend mit den σp+-Werten.Carbonyl chlorides 1 react with silver trifluoromethanesulfonate (2) and silver methanesulfonate (6) to give carboxylic trifluoromethanesulfonic anhydrides 3 and carboxylic methanesulfonic anhydrides 7, resp., in good yields; the anhydrides 3 may by synthesized from chlorides 1 and trifluoromethanesulfonic acid (4), too. Dissoziation of 3, even in 1,2-dichloroethane - depending on electronic and steric factors, was determined quantitatively. The dissoziation constants of 4-substituted 2,6-dimethylbenzoic trifluoromethanesulfonic anhydrides 3k-o correlate with the σp+-values satisfactorily

    Induced Gravity on Intersecting Branes

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    We establish Einstein-Hilbert gravity couplings in the effective action for Intersecting Brane Worlds. The four-dimensional induced Planck mass is determined by calculating graviton scattering amplitudes at one-loop in the string perturbation expansion. We derive a general formula linking the induced Planck mass for N=1 supersymmetric backgrounds directly to the string partition function. We carry out the computation explicitly for simple examples, obtaining analytic expressions.Comment: references added, minor changes to discussion of path integral normalization on page
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