WorldWideScience

Sample records for unit g2 zim-sci

  1. UPSS and G2

    Science.gov (United States)

    Dito, Scott J.

    2014-01-01

    The Universal Propellant Servicing System (UPSS) is a dedicated mobile launcher propellant delivery method that will minimize danger and complexity in order to allow vehicles to be serviced and ultimately launched from a variety of locations previously not seen fit for space launch. The UPPS/G2 project is the development of a model, simulation, and ultimately a working application that will control and monitor the cryogenic fluid delivery to the rocket for testing purposes. To accomplish this, the project is using the programming language/environment Gensym G2. The environment is an all-inclusive application that allows development, testing, modeling, and finally operation of the unique application through graphical and programmatic methods. We have learned G2 through classes and trial-and-error, and are now in the process of building the application that will soon be able to be tested on apparatuses here at Kennedy Space Center, and eventually on the actual unit. The UPSS will bring near-autonomous control of launches to those that need it, as well it will be a great addition to NASA and KSC's operational viability and the opportunity to bring space launches to parts of the world, and in time constraints, once not thought possible.

  2. The g-2 ring

    CERN Multimedia

    1974-01-01

    The precise measurement of "g-2", the anomalous magnetic moment of the muon, required a special muon storage ring with electrostatic focussing and very accurate knowledge of the magnetic bending field. For more details see under photo 7405430.

  3. Open G(2) strings

    NARCIS (Netherlands)

    de Boer, J.; de Medeiros, P.; El-Showk, S.; Sinkovics, A.

    2008-01-01

    We consider an open string version of the topological twist previously proposed for sigma-models with G(2) target spaces. We determine the cohomology of open strings states and relate these to geometric deformations of calibrated submanifolds and to flat or anti-self-dual connections on such submani

  4. G2 gauge theories

    CERN Document Server

    Maas, Axel

    2012-01-01

    QCD can be formulated using any gauge group. One particular interesting choice is to replace SU(3) by the exceptional group G2. Conceptually, this group is the simplest group with a trivial center. It thus permits to study the conjectured relevance of center degrees of freedom for QCD. Practically, since all its representation are real, it is possible to perform lattice simulations for this theory also at finite baryon densities. It is thus an excellent environment to test methods and to investigate general properties of gauge theories at finite densities. We review the status of our understanding of gauge theories with the gauge group G2, including Yang-Mills theory, Yang-Mills-Higgs theory, and QCD both in the vacuum and in the phase diagram.

  5. Muon g-2

    CERN Document Server

    Sichtermann, E P; Bousquet, B; Brown, H N; Bunce, G M; Carey, R M; Cushman, P B; Danby, G T; Debevec, P T; Deile, M; Deng, H; Deninger, W; Dhawan, S K; Druzhinin, V P; Duong, L; Efstathiadis, E F; Farley, F J M; Fedotovich, G V; Giron, S; Gray, F E; Grigoriev, D; Grosse-Perdekamp, M; Grossmann, A; Hare, M; Hertzog, D W; Huang, X; Hughes, V W; Iwasaki, M; Jungmann, Klaus; Kawall, D; Khazin, B I; Kindem, J; Krienen, F; Kronkvist, I J; Lam, A; Larsen, R; Lee, Y Y; Logashenko, I B; McNabb, R; Meng, W; Mi, J; Miller, J P; Morse, W M; Nikas, D; Onderwater, Gerco; Orlov, Yu F; Ozben; Paley, J M; Peng, Q; Polly, C C; Pretz, J; Prigl, R; zu Putlitz, Gisbert; Qian, T; Redin, S I; Rind, O; Roberts, B L; Ryskulov, N M; Shagin, P; Semertzidis, Y K; Shatunov, Yu M; Sichtermann, E P; Solodov, E; Sossong, M; Steinmetz, A; Sulak, L R; Trofimov, A; Urner, D; Von Walter, P; Warburton, D; Yamamoto, A

    2003-01-01

    The muon g-2 collaboration has measured the anomalous magnetic g value of the positive muon to within a relative uncertainty of 0.7 parts per million. The result, a_{\\mu^+} = 11 659 204(7)(5) x 10^{-10} is in good agreement with the preceding data on a_{\\mu^+} and a_{\\mu^-} and has about twice smaller uncertainty. The measurement tests standard model theory, which at the level of the experimental uncertainty involves quantum electrodynamics, quantum chromodynamics, and electroweak interaction in significant ways. The analysis of the anomalous magnetic g value of the negative muon is well underway.

  6. Confinement: G(2) group case

    CERN Document Server

    Cossu, G; Di Giacomo, A; Lucini, B; Pica, C

    2007-01-01

    The gauge group being centreless, $G_2$ gauge theory is a good laboratory for studying the role of the centre of the group for colour confinement in Yang-Mills gauge theories. In this paper, we investigate $G_2$ pure gauge theory at finite temperature on the lattice. By studying the finite size scaling of the plaquette, the Polyakov loop and their susceptibilities, we show that a deconfinement phase transition takes place. The analysis of the pseudocritical exponents give strong evidence of the deconfinement transition being first order. Implications of our findings for scenarios of colour confinement are discussed.

  7. Exceptional Confinement in G(2) Gauge Theory

    CERN Document Server

    Holland, K; Pepé, M; Wiese, U J

    2003-01-01

    We study theories with the exceptional gauge group G(2). The 14 adjoint "gluons" of a G(2) gauge theory transform as {3}, {3bar} and {8} under the subgroup SU(3), and hence have the color quantum numbers of ordinary quarks, anti-quarks and gluons in QCD. Since G(2) has a trivial center, a "quark" in the {7} representation of G(2) can be screened by "gluons". As a result, in G(2) Yang-Mills theory the string between a pair of static "quarks" can break. In G(2) QCD there is a hybrid consisting of one "quark" and three "gluons". In supersymmetric G(2) Yang-Mills theory with a {14} Majorana "gluino" the chiral symmetry is Z(4)_\\chi. Chiral symmetry breaking gives rise to distinct confined phases separated by confined-confined domain walls. A scalar Higgs field in the {7} representation breaks G(2) to SU(3) and allows us to interpolate between theories with exceptional and ordinary confinement. We also present strong coupling lattice calculations that reveal basic features of G(2) confinement. Just as in QCD, wher...

  8. $\\rm G_2$ holonomy manifolds are superconformal

    CERN Document Server

    Díaz, Lázaro O Rodríguez

    2016-01-01

    We study the chiral de Rham complex (CDR) over a manifold $M$ with holonomy $\\rm G_2$. We prove that the vertex algebra of global sections of the CDR associated to $M$ contains two commuting copies of the Shatashvili-Vafa $\\rm G_2$ superconformal algebra. Our proof is a tour de force, based on explicit computations.

  9. Exceptional Deconfinement in G(2) Gauge Theory

    CERN Document Server

    Pepé, M

    2006-01-01

    The Z(N) center symmetry plays an important role in the deconfinement phase transition of SU(N) Yang-Mills theory at finite temperature. The exceptional group G(2) is the smallest simply connected gauge group with a trivial center. Hence, there is no symmetry reason why the low- and high-temperature regimes in G(2) Yang-Mills theory should be separated by a phase transition. Still, we present numerical evidence for the presence of a first order deconfinement phase transition at finite temperature. Via the Higgs mechanism, G(2) breaks to its SU(3) subgroup when a scalar field in the fundamental {7} representation acquires a vacuum expectation value v. Varying v we investigate how the G(2) deconfinement transition is related to the one in SU(3) Yang-Mills theory. Interestingly, the two transitions seem to be disconnected. We also discuss a potential dynamical mechanism that may explain this behavior.

  10. The G2+G2t complex as a fast and massive outflow?

    CERN Document Server

    Ballone, A; Burkert, A; Gillessen, S; Plewa, P M; Genzel, R; Pfuhl, O; Eisenhauer, F; Ott, T; George, E M; Habibi, M

    2016-01-01

    Observations of the gas component of the cloud G2 in the Galactic Center have revealed its connection to a tail (G2t) lying on the same orbit. More recent studies indicate a connection between G2 and G1, another cloud detected on the blueshifted side of G2's orbit, suggesting a scenario in which G2 is a denser clump in a stream of gas. In this Letter we show that a simulation of an outflow by a central source (possibly a T Tauri star) moving on G2's orbit and interacting with a hot atmosphere surrounding SgrA* can have G2 and G2t as a byproduct. G2 would be the bow-shock formed in the head of the source, while G2t might be the result of the stripping of the rest of the shocked material by the ram pressure of the surrounding hot gas and of its successive accumulation in the trailing region. Mock position-velocity diagrams for the Br$\\gamma$ emission for this simulation can indeed reproduce the correct position and velocity of G2t, as well as the more tenuous material in between. Though some tension between the...

  11. G_2 gauge theory at finite temperature

    CERN Document Server

    Cossu, Guido; Di Giacomo, Adriano; Lucini, Biagio; Pica, Claudio

    2007-01-01

    The gauge group being centreless, $G_2$ gauge theory is a good laboratory for studying the role of the centre of the group for colour confinement in Yang-Mills gauge theories. In this paper, we investigate $G_2$ pure gauge theory at finite temperature on the lattice. By studying the finite size scaling of the plaquette, the Polyakov loop and their susceptibilities, we show that a deconfinement phase transition takes place. The analysis of the pseudocritical exponents give strong evidence of the deconfinement transition being first order. Implications of our findings for scenarios of colour confinement are discussed.

  12. M-theory and G_2 Manifolds

    CERN Document Server

    Becker, Katrin; Robbins, Daniel

    2015-01-01

    In this talk we report on recent progress in describing compactifications of string theory and M-theory on G_2 and Spin(7) manifolds. We include the infinite set of alpha'-corrections and describe the entire tower of massless and massive Kaluza-Klein modes resulting from such compactifications.

  13. Experimental measurement of muon (g-2)

    CERN Document Server

    Gray, F E

    2003-01-01

    The muon (g-2) experiment at Brookhaven National Laboratory has measured the anomalous magnetic moment of the positive muon with a precision of 0.7 ppm. This paper presents that result, concentrating on some of the important experimental issues that arise in extracting the anomalous precession frequency from the data.

  14. The Keplerian orbit of G2

    CERN Document Server

    Meyer, L; Witzel, G; Do, T; Phifer, K; Sitarski, B N; Morris, M R; Boehle, A; Yelda, S; Lu, J R; Becklin, E

    2013-01-01

    We give an update of the observations and analysis of G2 - the gaseous red emission-line object that is on a very eccentric orbit around the Galaxy's central black hole and predicted to come within 2400 Rs in early 2014. During 2013, the laser guide star adaptive optics systems on the W. M. Keck I and II telescopes were used to obtain three epochs of spectroscopy and imaging at the highest spatial resolution currently possible in the near-IR. The updated orbital solution derived from radial velocities in addition to Br-Gamma line astrometry is consistent with our earlier estimates. Strikingly, even ~6 months before pericenter passage there is no perceptible deviation from a Keplerian orbit. We furthermore show that a proposed "tail" of G2 is likely not associated with it but is rather an independent gas structure. We also show that G2 does not seem to be unique, since several red emission-line objects can be found in the central arcsecond. Taken together, it seems more likely that G2 is ultimately stellar in ...

  15. Probing Bino Contribution to Muon g-2

    CERN Document Server

    Endo, Motoi; Kikahara, Teppei; Yoshinaga, Takahiro

    2013-01-01

    We study SUSY models in which Bino contributions solve the muon $g-2$ anomaly. The contributions are enhanced by large left-right mixing of the smuons. However, it is constrained by the vacuum stability condition of the slepton--Higgs potential. Therefore, there are upper bounds on masses of sleptons and Bino. When the slepton soft masses are universal, the upper bound on the smuon mass becomes $330~(460)\\GeV$ in order to solve the $g-2$ anomaly at the $1\\sigma~(2\\sigma)$ level. It is within the reach of LHC and ILC. If the stau is heavier than the smuon, the bound can be as large as $1.4~(1.9)\\TeV$. Such non-universal slepton mass spectrum generically predicts too large LFV/CPV. We show that the models are expected to be probed by LHC/ILC and LFV/CPV complementarily in future.

  16. The "g-2" Muon Storage Ring

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    The "g-2" muon storage ring, shortly before completion in June 1974. Bursts of pions (from a target, hit by a proton beam from the 26 GeV PS) are injected and polarized muons from their decay are captured on a stable orbit. When the muons decay too, their precession in the magnetic field of the storage ring causes a modulation of the decay-electron counting rate, from which the muon's anomalous magnetic moment can be determined. In 1977, the "g-2" magnets were modified to build ICE (Initial Cooling Experiment), a proton and antiproton storage ring for testing stochastic and electron cooling. Later on, the magnets had a 3rd life, when the ion storage ring CELSIUS was built from them in Uppsala. For later use as ICE, see 7711282, 7802099, 7809081,7908242.

  17. Nonuniversal Gaugino Masses and Muon g-2

    CERN Document Server

    Gogoladze, Ilia; Shafi, Qaisar; Un, Cem Salih

    2014-01-01

    We consider two classes of supersymmetric models with nonuniversal gaugino masses at M_GUT in an attempt to resolve the apparent muon g-2 anomaly encountered in the Standard Model. We explore two distinct scenarios, one in which all gaugino masses have the same sign at M_GUT, and a second case with opposite sign gaugino masses. The sfermion masses in both cases are assumed to be universal at M_GUT. We exploit the non universality among gaugino masses to realize large mass splitting between the colored and non-colored sfermions. Thus, the sleptons can have masses in the few hundred GeV range, whereas the colored sparticles turn out to be an order of magnitude or so heavier. In both models the resolution of the muon g-2 anomaly is compatible, among other things, with a 125-126 GeV Higgs boson mass and the WMAP dark matter bounds.

  18. Solvability of the $G_2$ Integrable System

    CERN Document Server

    Capella, A; Turbiner, A V; Capella, Antonio; Rosenbaum, Marcos; Turbiner, Alexander

    1997-01-01

    It is shown that the 3-body trigonometric G_2 integrable system is exactly-solvable. If the configuration space is parametrized by certain symmetric functions of the coordinates then, for arbitrary values of the coupling constants, the Hamiltonian can be expressed as a quadratic polynomial in the generators of some Lie algebra of differential operators in a finite-dimensional representation. Four infinite families of eigenstates, represented by polynomials, and the corresponding eigenvalues are described explicitly.

  19. FEI Tecnai G2 F20

    Directory of Open Access Journals (Sweden)

    Martina Luysberg

    2016-06-01

    Full Text Available The FEI Titan Tecnai G2 F20 is a versatile transmission electron microscope which is equipped with a Gatan Tridiem 863P post column image filter (GIF and a high angle energy dispersive X-ray (EDX detector. This set up allows for a variety of experiments such as conventional imaging and diffraction, recording of bright- and dark-field scanning transmission electron microscopy (STEM images, or acquiring elemental maps extracted from energy electron loss spectra (EELS or EDX signals.

  20. M-theory and G2 manifolds

    Science.gov (United States)

    Becker, Katrin; Becker, Melanie; Robbins, Daniel

    2015-11-01

    In this talk we report on recent progress in describing compactifications of string theory and M-theory on G2 and Spin(7) manifolds. We include the infinite set of α’-corrections and describe the entire tower of massless and massive Kaluza-Klein modes resulting from such compactifications. Contribution to the ‘Focus Issue on Gravity, Supergravity and Fundamental Physics: the Richard Arnowitt Symposium’, to be published in Physica Scripta. Based on a talk delivered by Becker at the workshop ‘Superstring Perturbation Theory’ at the Perimeter Institute, 22-24 April 2015.

  1. Status of the Fermilab (g-2) experiment

    CERN Document Server

    Kaspar, J

    2015-01-01

    The upcoming muon (g-2) experiment at Fermilab will measure the anomalous magnetic moment of the muon to a relative precision of 140 ppb, 4 times better than the previous experiment at BNL. The new experiment is motivated by the persistent 3-4 standard deviations difference between the experimental value and the Standard Model prediction, and it will have the statistical sensitivity necessary to either refute the claim or confirm it with a confidence level exceeding a discovery threshold. The experiment is under construction and scheduled to start running in early 2017.

  2. Dual Superconductivity in G2 group

    CERN Document Server

    Cossu, G; Di Giacomo, Adriano; Lucini, B; Pica, C

    2006-01-01

    We investigate the dual superconductivity mechanism in the exceptional group $G_2$. This is a centerless group (no 't Hooft flux vortices are allowed) and we check for the presence of a magnetic monopole condensate in the confined phase by measuring on the lattice a disorder parameter related to the vacuum expectation value of an operator carrying magnetic charge. The behaviour of the disorder parameter is consistent with the dual superconductor picture. A first step of an analysis on the thermodynamical properties of the theory is conducted by mean of this operator.

  3. System Administration Support/SWORDS G2

    Science.gov (United States)

    Dito, Scott Joseph

    2014-01-01

    The Soldier-Warfighter Operationally Responsive Deployer for Space (SWORDS) rocket is a dedicated small satellite launcher that will minimize danger and complexity in order to allow soldiers in the field to put payloads of up to 25kg into orbit from the field. The SWORDSG2 project is the development of a model, simulation, and ultimately a working application that will control and monitor the cryogenic fluid delivery to the SWORDS rocket for testing purposes. To accomplish this, the project is using the programming language environment Gensym G2. The environment is an all-inclusive application that allows development, testing, modeling, and finally operation of the unique application through graphical and programmatic methods. In addition, observation of the current cryogenic fluid delivery system in the Kennedy Space Center Cry Lab has allowed me to gain valuable experience of fluid systems and propelant delivery that is valuable to our team when developing amd modeling our own system.The ultimate goal of having a test-ready application to show to the heads of the project, and demonstrating G2's capabilities, by late 2014 will require hard work and intense study and understanding of not only the programming aspect but also the physical phenomena we want to model, observe, and control.

  4. The Muon g-2 experiment at Fermilab

    Directory of Open Access Journals (Sweden)

    Anastasi A.

    2015-01-01

    Full Text Available There is a long standing discrepancy between the Standard Model prediction for the muon g-2 and the value measured by the Brookhaven E821 Experiment. At present the discrepancy stands at about three standard deviations, with a comparable accuracy between experiment and theory. Two new proposals – at Fermilab and J-PARC – plan to improve the experimental uncertainty by a factor of 4, and it is expected that there will be a significant reduction in the uncertainty of the Standard Model prediction. I will review the status of the planned experiment at Fermilab, E989, which will analyse 21 times more muons than the BNL experiment and discuss how the systematic uncertainty will be reduced by a factor of 3 such that a precision of 0.14 ppm can be achieved.

  5. The muon g-2 experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Gohn, W. [Kentucky U.

    2016-11-15

    A new measurement of the anomalous magnetic moment of the muon, $a_{\\mu} \\equiv (g-2)/2$, will be performed at the Fermi National Accelerator Laboratory with data taking beginning in 2017. The most recent measurement, performed at Brookhaven National Laboratory and completed in 2001, shows a 3.5 standard deviation discrepancy with the standard model prediction of $a_\\mu$. The new measurement will accumulate 21 times those statistics using upgraded detection and storage ring systems, enabling a measurement of $a_\\mu$ to 140 ppb, a factor of 4 improvement in the uncertainty the previous measurement. This improvement in precision, combined with recent and ongoing improvements in the evaluation of the QCD contributions to the $a_\\mu$, could provide a 7.5$\\sigma$ discrepancy from the standard model if the current difference between experiment and theory is confirmed, a possible indication of new physics.

  6. The muon g-2 experiment at Fermilab

    CERN Document Server

    Gohn, W

    2016-01-01

    A new measurement of the anomalous magnetic moment of the muon, $a_{\\mu} \\equiv (g-2)/2$, will be performed at the Fermi National Accelerator Laboratory with data taking beginning in 2017. The most recent measurement, performed at Brookhaven National Laboratory and completed in 2001, shows a 3.5 standard deviation discrepancy with the standard model prediction of $a_\\mu$. The new measurement will accumulate 21 times those statistics using upgraded detection and storage ring systems, enabling a measurement of $a_\\mu$ to 140 ppb, a factor of 4 improvement in the uncertainty the previous measurement. This improvement in precision, combined with recent and ongoing improvements in the evaluation of the QCD contributions to the $a_\\mu$, could provide a 7.5$\\sigma$ discrepancy from the standard model if the current difference between experiment and theory is confirmed, a possible indication of new physics.

  7. Positronium contribution to the electron g-2

    Science.gov (United States)

    Fael, M.; Passera, M.

    2014-09-01

    The contribution of positronium to the electron g-2 (ae) has been computed in G. Mishima, arXiv:1311.7109, and found to be of the same order of α as that of five-loop perturbative QED. We confirm this result and correct a few errors in its first derivation. As recently calculated in K. Melnikov, A. Vainshtein, and M. Voloshin, arXiv:1402.5690, a continuum nonperturbative contribution to ae cancels one-half of the positronium one. We show by explicit calculation that the remaining half is already included in the five-loop perturbative result. We also show that it arises from the class I(i) of five-loop diagrams containing only one closed electron loop.

  8. Muon (g-2) Technical Design Report

    CERN Document Server

    Grange, J; Winter, P; Wood, K; Zhao, H; Carey, R M; Gastler, D; Hazen, E; Kinnaird, N; Miller, J P; Mott, J; Roberts, B L; Benante, J; Crnkovic, J; Morse, W M; Sayed, H; Tishchenko, V; Druzhinin, V P; Khazin, B I; Koop, I A; Logashenko, I; Shatunov, Y M; Solodov, E; Korostelev, M; Newton, D; Wolski, A; Bjorkquist, R; Eggert, N; Frankenthal, A; Gibbons, L; Kim, S; Mikhailichenko, A; Orlov, Y; Rubin, D; Sweigart, D; Allspach, D; Annala, G; Barzi, E; Bourland, K; Brown, G; Casey, B C K; Chappa, S; Convery, M E; Drendel, B; Friedsam, H; Gadfort, T; Hardin, K; Hawke, S; Hayes, S; Jaskierny, W; Johnstone, C; Johnstone, J; Kashikhin, V; Kendziora, C; Kiburg, B; Klebaner, A; Kourbanis, I; Kyle, J; Larson, N; Leveling, A; Lyon, A L; Markley, D; McArthur, D; Merritt, K W; Mokhov, N; Morgan, J P; Nguyen, H; Ostiguy, J-F; Para, A; Popovic, C C Polly M; Ramberg, E; Rominsky, M; Schoo, D; Schultz, R; Still, D; Soha, A K; Strigonov, S; Tassotto, G; Turrioni, D; Villegas, E; Voirin, E; Velev, G; Wolff, D; Worel, C; Wu, J-Y; Zifko, R

    2015-01-01

    The Muon (g-2) Experiment, E989 at Fermilab, will measure the muon anomalous magnetic moment a factor-of-four more precisely than was done in E821 at the Brookhaven National Laboratory AGS. The E821 result appears to be greater than the Standard-Model prediction by more than three standard deviations. When combined with expected improvement in the Standard-Model hadronic contributions, E989 should be able to determine definitively whether or not the E821 result is evidence for physics beyond the Standard Model. After a review of the physics motivation and the basic technique, which will use the muon storage ring built at BNL and now relocated to Fermilab, the design of the new experiment is presented. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2/3 approval.

  9. A G2-QCD neutron star

    CERN Document Server

    Hajizadeh, Ouraman

    2016-01-01

    The determination of the properties of neutron stars from the underlying theory, QCD, is still an unsolved problem. This is mainly due to the difficulty to obtain reliable results for the equation of state for cold, dense QCD. As an alternative route to obtain qualitative insights, we determine the structure of a neutron star for a modified version of QCD: By replacing the gauge group SU(3) with the exceptional Lie group G2, it is possible to perform lattice simulations at finite density, while still retaining neutrons. Here, results of these lattice simulations are used to determine the mass-radius relation of a neutron star for this theory. The results show that phase changes express themselves in this relation. Also, the radius of the most massive neutron stars is found to vary very little, which would make radius determinations much simpler if this would also be true in QCD.

  10. Hadronic Contribution to $(g-2)_{\\mu}$

    CERN Document Server

    Höcker, A

    2001-01-01

    The recent precise measurement of the muon magnetic anomaly (g-2)_{mu} at BNL opens a window into possible new physics, provided the contribution from hadronic vacuum polarization is well understood. This talk summarizes the development in the evaluation of the leading order hadronic contributions. Significant improvement has been achieved in a series of analyses which is presented historically in three steps: (1), use of tau spectral functions in addition to e+e- cross sections, (2), extended use of perturbative QCD and (3), application of QCD sum rule techniques. The uncertainties, in particular concerning the CVC hypothesis used in step (1), and global quark-hadron duality employed in steps (2) and (3) are discussed. No new analysis results are given in these proceedings.

  11. Muon (g-2) Technical Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Grange, J. [Argonne National Lab. (ANL), Argonne, IL (United States); et al.

    2015-01-27

    The Muon (g-2) Experiment, E989 at Fermilab, will measure the muon anomalous magnetic moment a factor-of-four more precisely than was done in E821 at the Brookhaven National Laboratory AGS. The E821 result appears to be greater than the Standard-Model prediction by more than three standard deviations. When combined with expected improvement in the Standard-Model hadronic contributions, E989 should be able to determine definitively whether or not the E821 result is evidence for physics beyond the Standard Model. After a review of the physics motivation and the basic technique, which will use the muon storage ring built at BNL and now relocated to Fermilab, the design of the new experiment is presented. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2/3 approval.

  12. Essentials of the muon g-2

    Energy Technology Data Exchange (ETDEWEB)

    Jegerlehner, F. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik]|[Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2007-03-15

    The muon anomalous magnetic moment is one of the most precisely measured quantities in particle physics. Recent high precision measurements (0.54 ppm) at Brookhaven reveal a ''discrepancy'' by 3 standard deviations from the electroweak Standard Model which could be a hint for an unknown contribution from physics beyond the Standard Model. This triggered numerous speculations about the possible origin of the ''missing piece''. The remarkable 14-fold improvement of the previous CERN experiment, actually animated a multitude of new theoretical efforts which lead to a substantial improvement of the prediction of a{sub {mu}}. The dominating uncertainty of the prediction, caused by strong interaction effects, could be reduced substantially, due to new hadronic cross section measurements in electron-positron annihilation at low energies. After an introduction and a brief description of the principle of the experiment, I present a major update and review the status of the theoretical prediction and discuss the role of the hadronic vacuum polarization effects and the hadronic light-by-light scattering contribution. Prospects for the future are briefly discussed. As, in electroweak precision physics, the muon g-2 shows the largest established deviation between theory and experiment at present, it will remain one of the hot topics for further investigations. (orig.)

  13. G2 Checkpoint Responses in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Britt, Anne

    2013-03-18

    This project focused on the mechanism and biological significance of the G2 arrest response to replication stress in plants. We employed both forward and reverse genetic approaches to identify genes required for this response. A total of 3 different postdocs, 5 undergraduates, and 2 graduate students participated in the project. We identified several genes required for damage response in plants, including homologs of genes previously identified in animals (ATM and ATR), novel, a plant-specific genes (SOG1) and a gene known in animals but previously thought to be missing from the Arabidopsis genome (ATRIP). We characterized the transcriptome of gamma-irradiated plants, and found that plants, unlike animals, express a robust transcriptional response to damage, involving genes that regulate the cell cycle and DNA metabolism. This response requires both ATM and the transcription factor SOG1. We found that both ATM and ATR play a role in meiosis in plants. We also found that plants have a cell-type-specific programmed cell death response to ionizing radiation and UV light, and that this response requires ATR, ATM, and SOG1. These results were published in a series of 5 papers.

  14. Batch process. Batch plant scheduling using an intelligent system developing tool (G2); Interijento system kaihatsu tsuru ( G2 ) wo mochiita bacchi puranto sukejuringu

    Energy Technology Data Exchange (ETDEWEB)

    Fukuoka, H. [Itochu Technology Science Co. Ltd. (Japan)

    1997-09-05

    G2 is used in many industrial fields as a tool capable of forming in a comparatively short period of time various kinds of high-degree intelligent system including a scheduling system. This paper introduces G2, and then describes a batch scheduling system. The software techniques provided by G2 include the techniques concerning a real time system, an expert system, a graphic user interface, and object-oriented security network. G2 has a striking feature that it is a developing tool adapted to enable these software techniques to be utilized in a united environment. A program developed by G2 has a feature that it can be operated as it is without changing the source program at all even when the program is used in a machine of another OS. The paper introduces a beer production scheduling system as an actual example. 3 figs.

  15. Harmonic maps of finite uniton number into $G_2$

    CERN Document Server

    Correia, N

    2010-01-01

    We establish explicit formulae for canonical factorizations of extended solutions corresponding to harmonic maps of finite uniton number into the exceptional Lie group $G_2$ in terms of the Grassmannian model for the group of based algebraic loops in $G_2$. A description of the ``Frenet frame data" for such harmonic maps is given. In particular, we show that harmonic spheres into $G_2$ correspond to solutions of certain algebraic systems of quadratic and cubic equations.

  16. Surface Grafted Glycopolymer Brushes to Enhance Selective Adhesion of HepG2 Cells

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Jensen, Bettina Elisabeth Brøgger; Shimizu, Kyoko

    2013-01-01

    process on a previously formed poly(LAMA) brushes. The morphology of human hepatocellular carcinoma cancer cells (HepG2) on the comb-like poly(LAMA) brush layer has been studied. The fluorescent images of the HepG2 cells on the glycopolymer brush surface display distinct protrusions that extend outside...... of the cell periphery. On the other hand the cells on bare glass substrate display spheroid morphology. Further analysis using ToF-SIMS imaging shows that the HepG2 cells on glycopolymer surfaces is enriched with protein fragment along the cell periphery which is absent in the case of cells on bare glass...... substrate. It is suggested that the interaction of the galactose units of the polymer brush with the asialoglycoprotein receptor (ASGPR) of HepG2 cells has resulted in the protein enrichment along the cell periphery....

  17. Small-x asymptotics of structure function $g_2$

    CERN Document Server

    Ermolaev, B I

    1997-01-01

    Nonsinglet structure function g_2(x) for deep inelastic scattering of a lepton on a constituent quark is calculated in the double logarithmic approximation at x<<1. Small-x asymptotics of g_2 is shown to have the same singular behaviour as asymptotics of the nonsinglet structure function g_1.

  18. The superconducting inflector for the BNL g-2 experiment

    NARCIS (Netherlands)

    Yamamoto, A; Makida, Y; Tanaka, K; Krieman, F; Roberts, BL; Brown, HN; Bunce, G; Danby, GT; G-Perdekamp, M; Hseuh, H; Jia, L.; Lee, YY; Mapes, M; Meng, W; Morse, W; Pai, C; Prigl, R; Sampson, W; Sandberg, J; Suenaga, M; Tallerico, T; Toldo, F; Woodle, K; Green, MA; Itoh, I.; Otsuka, H.; Saito, Y; Ozawa, T; Tachiya, Y; Tanaka, H; Grossmann, A; Jungmann, K; Putlitz, GZ; Deng, H; Dhawan, S; Hughes, Robert E; Kawall, D; Pretz, J; Redin, S; Sichtermann, E; Steinmetz, A

    2002-01-01

    The muon g-2 experiment at Brookhaven National Laboratory (BNL) has the goal of determining the muon anomalous magnetic moment, a(mu) (= (g-2)/2), to the very high precision of 0.35 parts per million and thus requires a storage ring magnet with great stability and homogeneity. A super-ferric storage

  19. Superconductivity in noncentrosymmetric A g2P d3S

    Science.gov (United States)

    Yoshida, H.; Okabe, H.; Matsushita, Y.; Isobe, M.; Takayama-Muromachi, E.

    2017-05-01

    We have successfully synthesized the single crystal of A g2P d3S , which exhibits superconductivity with the transition temperature of Tc=2.25 K . A g2P d3S crystallizes in the space group P 4132 with the filled β -Mn structure, which has no inversion symmetry. The value of the Ginzburg-Landau parameter κGL indicates that A g2P d3S is a type-II superconductor. Δ C (Tc) /γnTc=1.50 and 2 Δ /kBTc=3.48 from the heat-capacity analyses indicate that A g2P d3S is a weak-coupling Bardeen-Cooper-Schrieffer (BCS) superconductor with an isotropic superconducting gap. On the other hand, the violation of the Werthamer-Helfand-Hohenberg curve in the H -T phase diagram implies A g2P d3S is not a typical BCS superconductor.

  20. Viral infections and cell cycle G2/M regulation

    Institute of Scientific and Technical Information of China (English)

    Richard Y.ZHAO; Robert T.ELDER

    2005-01-01

    Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both human and fission yeast(Schizosaccharomyces pombe) cells, the activity of Cdc2 is regulated in part by the phosphorylation status of tyrosine 15(Tyr15) on Cdc2, which is phosphorylated by Wee1 kinase during late G2 and is rapidly dephosphorylated by the Cdc25 tyrosine phosphatase to trigger entry into mitosis. These Cdc2 regulators are the downstream targets of two well-characterized G2/M checkpoint pathways which prevent cells from entering mitosis when cellular DNA is damaged or when DNA replication is inhibited. Increasing evidence suggests that Cdc2 is also commonly targeted by viral proteins,which modulate host cell cycle machinery to benefit viral survival or replication. In this review, we describe the effect of viral protein R (Vpr) encoded by human immunodeficiency virus type 1 (HIV-1) on cell cycle G2/M regulation. Based on our current knowledge about this viral effect, we hypothesize that Vpr induces cell cycle G2 arrest through a mechanism that is to some extent different from the classic G2/M checkpoints. One the unique features distinguishing Vpr-induced G2 arrest from the classic checkpoints is the role of phosphatase 2A (PP2A) in Vpr-induced G2 arrest.Interestingly, PP2A is targeted by a number of other viral proteins including SV40 small T antigen, polyomavirus T antigen, HTLV Tax and adenovirus E4orf4. Thus an in-depth understanding of the molecular mechanisms underlying Vpr-induced G2 arrest will provide additional insights into the basic biology of cell cycle G2/M regulation and into the biological significance of this effect during host-pathogen interactions.

  1. The partial characterization of the antibacterial peptide bacteriocin G2 produced by the probiotic bacteria Lactobacillus plantarum G2

    Directory of Open Access Journals (Sweden)

    SVETLANA L. ŠEATOVIĆ

    2011-05-01

    Full Text Available The aim of this study was the partial characterization of the antimicrobial peptide bacteriocin G2 produced by probiotic bacteria Lactobacillus plantarum G2, which was isolated from a clinical sample of a healthy person. Antimicrobial substance was secreted in the supernatant of an L. plantarum G2 culture, and showed a diverse spectrum of antimicrobial activity of all the tested strains of the genera Lactobacillus and the pathogenic bacteria Staphylococcus aureus and Salmonella аbony. Isoelectric focusing revealed that bacteriocin G2 is a cationic peptide (pI about 10 with a molecular mass of 2.2 kDa according to tricine–sodium dodecyl sulphate–polyacrylamide gel electrophoresis, SDS-PAGE. The antimicrobial activity of bacteriocin G2 was diminished by the proteolytic action of trypsin and proteinase K. Bacteriocin G2 preserved its biological activity in the temperature range 40–60 °C (15 min, which was lost at 80 °C. Bacteriocin G2 was stable in the pH range 2–9, while treatment with 1 % Tween 80 and 1 % urea resulted in increased antimicrobial activity. The probiotic strain L. plantarum G2 produces the antimicrobial substance proteinaceous in nature with bacteriocin characteristics. Bacteriocin production is one of the key properties of probiotic bacteria with clinical potential as anti-infective agents, which will increase the likelihood of its in vivo efficacy.

  2. The effect of natural adjuvants (G2, G2F on lung inflammation of sensitized guinea pigs

    Directory of Open Access Journals (Sweden)

    Ali Neamati

    2013-07-01

    Full Text Available Objective: The effects of natural adjuvants were examined on total and differential WBC counts in lung lavage of sensitized guinea pigs. Materials and Methods: In three sensitized groups of guinea pigs including: untreated sensitized animals (S, sensitized animals treated with adjuvant G2 (S+G2 and G2F (S+G2F as well as non-sensitized group (C (n=6 for each group, total and differential WBC counts of lung lavage were examined. Sensitization of animals was achieved by injection and inhalation of ovalbumin (OA. Results: The results showed increased total WBC, eosinophil, neutrophil, and basophil counts, and decreased lymphocytes in lung lavage of sensitized animals compared with the control group (pConclusion: These results indicate important preventive effects of two natural adjuvants, especially G2, on lung inflammation of sensitized guinea pigs.  

  3. Visualizing Vpr-induced G2 arrest and apoptosis.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Murakami

    Full Text Available Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1 with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2. The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to

  4. Muon g-2 vs LHC in Supersymmetric Models

    CERN Document Server

    Endo, Motoi; Iwamoto, Sho; Yoshinaga, Takahiro

    2013-01-01

    There is more than 3 sigma deviation between the experimental and theoretical results of the muon g-2. This suggests that some of the SUSY particles have a mass of order 100 GeV. We study searches for those particles at the LHC with particular attention to the muon g-2. In particular, the recent results on the searches for the non-colored SUSY particles are investigated in the parameter region where the muon g-2 is explained. The analysis is independent of details of the SUSY models. Future prospects of the collider searches are also discussed.

  5. VLT Observations of the Gas Cloud G2

    Science.gov (United States)

    Gillessen, Stefan

    2014-01-01

    In 2011, we discovered a small, compact gas cloud G2 that is falling on a near-radial orbit toward the massive black hole in the Galactic Center. The orbit is well-constrained and the pericenter passage will occur in early 2014. Our data beautifully show that G2 gets tidally sheared apart due to the massive black hole's force. We expect that in addition to the tidal effects, hydrodynamics will become important when G2 collides with the hot ambient gas around Sgr A*. This might be a unique opportunity in the next years to observe how gas feeds a massive black hole.

  6. Theory of G2 Cloud Multi-Wavelength Emission

    CERN Document Server

    Shcherbakov, Roman V

    2013-01-01

    An object called G2 was recently discovered moving towards the supermassive black hole in the Galactic Center. G2 emits infrared (IR) lines and continuum, which allows constraining its properties. The question is still unresolved whether G2 has a central windy star or it is a coreless cloud. Assuming the object is a cloud originating near the apocenter I perform line/continuum IR diagnostics, revisit estimates of non-thermal emission from pericenter passage, and speculate about future observational prospects. This work is partially reported in arXiv:1309.2282 and partially consists of new ideas discussed at the conference.

  7. Confinement without a center the exceptional group G(2)

    CERN Document Server

    Holland, K; Pepé, M; Wiese, U J

    2002-01-01

    We discuss theories with the exceptional centerless gauge group G(2), paying attention to confinement and the pattern of chiral symmetry breaking. Exploiting the Higgs mechanism to break the symmetry down to SU(3), we also present how the familiar features of confinement and chiral symmetry breaking of SU(3) gauge theories reemerge. G(2) gauge theories show up as an unusual theoretical framework to study SU(3) gauge theories without the ``luxury'' of a center.

  8. A note on G2 log-aesthetic curves

    Science.gov (United States)

    Wo, Mei Seen; Gobithaasan R., U.; Miura, Kenjiro T.; Abbas, Muhammad

    2015-12-01

    Log-aesthetic curve (LAC) is a curve family composed of transcendental curves that includes logarithmic spiral, clothoid, circle involute and Nielsen's spiral. They have linear logarithmic curvature graphs (LCGs) and are highly aesthetic. In order to implement G2 LAC in industrial design successfully, one needs guidance on the existence and uniqueness whether a LAC segment satisfy given G2 Hermite data. This paper focuses shows the existence and uniqueness of solution for single segment G2 LAC. A LAC equation that incorporates both start and end curvatures, and end tangential angle is first derived. Then, the end points of the LAC segments are calculated using the derived LAC equation, which is also a representation of the solution region of LAC given a set of G2 Hermite data. The derived function is investigated for its existence and uniqueness. It is shown that the solution region is a curve that do not self-intersect anywhere, thus the solution of single segment G2 LAC is always unique.

  9. Infinitesimal moduli of G2 holonomy manifolds with instanton bundles

    CERN Document Server

    de la Ossa, Xenia; Svanes, Eirik Eik

    2016-01-01

    We describe the infinitesimal moduli space of pairs $(Y, V)$ where $Y$ is a manifold with $G_2$ holonomy, and $V$ is a vector bundle on $Y$ with an instanton connection. These structures arise in connection to the moduli space of heterotic string compactifications on compact and non-compact seven dimensional spaces, e.g. domain walls. Employing the canonical $G_2$ cohomology $H^*_{{\\check{\\rm d}}_E}(Y,E)$ developed by Reyes-Carri\\'on and Fern\\'andez and Ugarte, we show that the moduli space decomposes into the sum of the bundle moduli $H^1_{{\\check{\\rm d}}_A}(Y,{\\rm End}(V))$ plus the moduli of the $G_2$ structure preserving the instanton condition. The latter piece is contained in $H^1_{{\\check{\\rm d}}_\

  10. Effective Polyakov Loop Dynamics for Finite Temperature G(2) Gluodynamics

    CERN Document Server

    Wellegehausen, Bjoern H; Wozar, Christian

    2009-01-01

    Based on the strong coupling expansion we obtain effective 3-dimensional models for the Polyakov loop in finite-temperature G_2 gluodynamics. The Svetitsky-Jaffe conjecture relates the resulting continuous spin models with G_2 gluodynamics near phase transition points. In the present work we analyse the effective theory in leading order with the help of a generalised mean field approximation and with detailed Monte-Carlo simulations. In addition we derive a Potts-type discrete spin model by restricting the characters of the Polyakov loops to the three extremal points of the fundamental domain of G_2. Both the continuous and discrete effective models show a rich phase structure with a ferromagnetic, symmetric and several anti-ferromagnetic phases. The phase diagram contains first and second order transition lines and tricritical points. The modified mean field predictions compare very well with the results of our simulations.

  11. Performance analysis for the new G-2 experiment

    CERN Document Server

    Stratakis, D; Johnstone, C; Johnstone, J; Morgan, J P; Syphers, M J; Crmkovic, J D; Morse, W M; Tishchenko, V; Froemming, N S; Korostelev, M

    2016-01-01

    The new g-2 experiment at Fermilab aims to measure the muon anomalous magnetic moment by a fourfold improvement in precision compared to the BNL experiment. Achieving this goal requires the delivery of highly polarized 3.094 GeV/c muons with a narrow +-0.5% {\\Delta}p/p acceptance to the storage ring. In this study, we describe a muon capture and transport scheme that should meet this requirement. First, we present the conceptual design of our proposed scheme wherein we describe its basic features. Then, we detail our numerical model and present a complete end-to-end simulation of all g-2 beamlines.

  12. The new (g-2)mu experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Brendan C.K.; /Fermilab

    2009-01-01

    We present a proposal to measure the anomalous magnetic moment of the muon to 0.14 ppm precision. This new g-2 experiment will be hosted by Fermilab making use of minor modifications to the existing accelerator complex. The experiment will recycle several components from the previous g-2 experiment E821 hosted at Brookhaven. In particular, the entire storage ring and magnet will be shipped to Fermilab. We cover the motivation for the experiment and review the measurement technique. We then focus on a new in-vacuo straw tracking system planned for the new experiment and its impact on searching for a permanent electric dipole moment of the muon.

  13. NEW RESULTS FROM THE MUON G - 2 EXPERIMENT.

    Energy Technology Data Exchange (ETDEWEB)

    SICHTERMANN,E.P.BENNETT,G.W.BOUSQUET,B.BROWN,H.N.BUNCE,G.CAREY,R.M.ET ALMUON G - 2 COLLABORATION

    2002-09-09

    The Muon g-2 collaboration has measured the anomalous magnetic g value, a = (g-2)/2, of the positive muon with an unprecedented uncertainty of O.7parts per million. The result a{sub {mu}{sup +}}(expt) = 11 659 204(7)(5) x 10{sup -10}, based on data collected in the year 2000 at Brookhaven National Laboratory, is in good agreement with the preceding data on a{sub {mu}{sup +}} and a{sub {mu}{sup -}}. The measurement tests standard model theory, which at the level of the current experimental uncertainty involves quantum electrodynamics, quantum chromodynamics, and electroweak interaction in a significant way.

  14. Muon g-2 Anomaly and Dark Leptonic Gauge Boson

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hye-Sung [W& M

    2014-11-01

    One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.

  15. Overview of the Fermilab Muon g-2 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, SeungCheon [Cornell U., Phys. Dept.

    2015-01-01

    The measurement of the anomalous magnetic moment of muon provides a precision test of the Standard Model. The Brookhaven muon g-2 experiment (E821) measured the muon magnetic moment anomaly with 0.54 ppm precision, a more than 3 deviation from the Standard Model predictions, spurring speculation about the possibility of new physics. The new g-2 experiment at Fermilab (E989) will reduce the combined statistical and systematic error of the BNL experiment by a factor of 4. An overview of the new experiment is described in this article.

  16. G2 Autonomous Control for Cryogenic Delivery Systems

    Science.gov (United States)

    Dito, Scott J.

    2014-01-01

    The Independent System Health Management-Autonomous Control (ISHM-AC) application development for cryogenic delivery systems is intended to create an expert system that will require minimal operator involvement and ultimately allow for complete autonomy when fueling a space vehicle in the time prior to launch. The G2-Autonomous Control project is the development of a model, simulation, and ultimately a working application that will control and monitor the cryogenic fluid delivery to a rocket for testing purposes. To develop this application, the project is using the programming language/environment Gensym G2. The environment is an all-inclusive application that allows development, testing, modeling, and finally operation of the unique application through graphical and programmatic methods. We have learned G2 through training classes and subsequent application development, and are now in the process of building the application that will soon be used to test on cryogenic loading equipment here at the Kennedy Space Center Cryogenics Test Laboratory (CTL). The G2 ISHM-AC application will bring with it a safer and more efficient propellant loading system for the future launches at Kennedy Space Center and eventually mobile launches from all over the world.

  17. The Polarized Structure Function $g_{2} A Lattice Study Revisited

    CERN Document Server

    Göckeler, M; Kürzinger, W; Oelrich, H; Rakow, P; Schierholz, G

    1999-01-01

    A recent lattice calculation of the spin-dependent structure function g_2 is revisited. It has been recognized that the twist-three operator, which gives rise to d_2, mixes non-perturbatively with operators of lower dimensions under renormalization. This changes the results substantially.

  18. Fermilab Muon Campus g-2 Cryogenic Distribution Remote Control System

    CERN Document Server

    Pei, L; Klebaner, A; Soyars, W; Bossert, R

    2015-01-01

    The Muon Campus (MC) is able to measure Muon g-2 with high precision and comparing its value to the theoretical prediction. The MC has four 300 KW screw compressors and four liquid helium refrigerators. The centerpiece of the Muon g-2 experiment at Fermilab is a large, 50-foot-diameter superconducting muon storage ring. This one-of-a-kind ring, made of steel, aluminum and superconducting wire, was built for the previous g-2 experiment at Brookhaven. Due to each subsystem has to be far away from each other and be placed in the distant location, therefore, Siemens Process Control System PCS7-400, Automation Direct DL205 & DL05 PLC, Synoptic and Fermilab ACNET HMI are the ideal choices as the MC g-2 cryogenic distribution real-time and on-Line remote control system. This paper presents a method which has been successfully used by many Fermilab distribution cryogenic real-time and On-Line remote control systems.

  19. Bound State Effect on the Electron g-2

    CERN Document Server

    Mishima, Go

    2013-01-01

    We evaluate a non-perturbative QED contribution to the electron g-2 which comes from virtual positronium. We find it to be 9.0*10^{-14}. This value is comparable to the five-loop contribution of usual perturbative calculation, and several times larger than the electroweak correction.

  20. Measuring the performance of G2G services in Iran

    Science.gov (United States)

    Zarei, Behrouz; Safdari, Maryam

    To highlight the growth of e-government and the importance of its services it is essential to evaluate the performance of the service delivery to customers. Research indicates that traditional performance indexes are not suitable for this evaluation; moreover, it is noticeable that the e-government services are intangible and invisible. Among different e-government services, measurement of quality government to government (G2G) services has been less attractive for researchers while crucial for government policy-makers. This calls for a better understanding of the specific needs of users of these services in order to provide appropriate type and level of services that meets those needs. In this paper, the performance of the G2G services is measured in the Iranian context. For this purpose, SERVQUAL, which is a well-known method for assessing service quality, is employed. This study proposes and tests a five-factor of SERVQUAL instrument to explain user satisfaction and gap analysis, between expectations and perceptions of its customers, consisting thirty ministries and main governmental organizations. Based on a Chi-square test, factor analysis, gap analysis and correlations, it is concluded the gap between expectations and perceptions of G2G customers is significant and customer satisfaction of G2G services is at low level.

  1. A 4D gravity theory and G2-holonomy manifolds

    CERN Document Server

    Herfray, Yannick; Scarinci, Carlos; Shtanov, Yuri

    2016-01-01

    Bryant and Salamon gave a construction of metrics of G2 holonomy on the total space of the bundle of anti-self-dual (ASD) 2-forms over a 4-dimensional self-dual Einstein manifold. We generalise it by considering the total space of an SO(3) bundle (with fibers R^3) over a 4-dimensional base, with a connection on this bundle. We make essentially the same ansatz for the calibrating 3-form, but use the curvature 2-forms instead of the ASD ones. We show that the resulting 3-form defines a metric of G2 holonomy if the connection satisfies a certain second-order PDE. This is exactly the same PDE that arises as the field equation of a certain 4-dimensional gravity theory formulated as a diffeomorphism-invariant theory of SO(3) connections. Thus, every solution of this 4-dimensional gravity theory can be lifted to a G2-holonomy metric. Unlike all previously known constructions, the theory that we lift to 7 dimensions is not topological. Thus, our construction should give rise to many new metrics of G2 holonomy. We des...

  2. Oncogenic pathways impinging on the G2-restriction point

    NARCIS (Netherlands)

    Foijer, F; Simonis, M; van Vliet, M; Wessels, L; Kerkhoven, R; Sorger, P K; Te Riele, H

    2008-01-01

    In the absence of mitogenic stimuli, cells normally arrest in G(1/0), because they fail to pass the G1-restriction point. However, abrogation of the G1-restriction point (by loss of the retinoblastoma gene family) reveals a second-restriction point that arrests cells in G2. Serum-starvation-induced

  3. G2Cdb: the Genes to Cognition database

    Science.gov (United States)

    Croning, Mike D. R.; Marshall, Michael C.; McLaren, Peter; Armstrong, J. Douglas; Grant, Seth G. N.

    2009-01-01

    Neuroscience databases linking genes, proteins, (patho)physiology, anatomy and behaviour across species will be valuable in a broad range of studies of the nervous system. G2Cdb is such a neuroscience database aiming to present a global view of the role of synapse proteins in physiology and disease. G2Cdb warehouses sets of genes and proteins experimentally elucidated by proteomic mass spectroscopy of signalling complexes and proteins biochemically isolated from mammalian synapse preparations, giving an experimentally validated definition of the constituents of the mammalian synapse. Using automated text-mining and expert (human) curation we have systematically extracted information from published neurobiological studies in the fields of synaptic signalling electrophysiology and behaviour in knockout and other transgenic mice. We have also surveyed the human genetics literature for associations to disease caused by mutations in synaptic genes. The synapse proteome datasets that G2Cdb provides offer a basis for future work in synapse biology and provide useful information on brain diseases. They have been integrated in a such way that investigators can rapidly query whether a gene or protein is found in brain-signalling complex(es), has a phenotype in rodent models or whether mutations are associated with a human disease. G2Cdb can be freely accessed at http://www.genes2cognition.org. PMID:18984621

  4. Hydrodynamical simulations of a compact source scenario for G2

    CERN Document Server

    Ballone, A; Burkert, A; Gillessen, S; Genzel, R; Fritz, T K; Eisenhauer, F; Pfuhl, O; Ott, T

    2013-01-01

    The origin of the dense gas cloud G2 discovered in the Galactic Center (Gillessen et al. 2012) is still a debated puzzle. G2 might be a diffuse cloud or the result of an outflow from an invisible star embedded in it. We present here detailed simulations of the evolution of winds on G2's orbit. We find that the hydrodynamic interaction with the hot atmosphere present in the Galactic Center and the extreme gravitational field of the supermassive black hole must be taken in account when modeling such a source scenario. We find that the hydrodynamic interaction with the hot atmosphere present in the Galactic Center and the extreme gravitational field of the supermassive black hole must be taken in account when modeling such a source scenario. We also find that in this scenario most of the Br\\gamma\\ luminosity is expected to come from the highly filamentary densest shocked wind material. G2's observational properties can be used to constrain the properties of the outflow and our best model has a mass outflow rate ...

  5. Perfect Crystals of $U_{q}(G_{2}^{(1)})$

    CERN Document Server

    Yamane, S

    1997-01-01

    The notion of perfect crystals was introduced in "Perfect Crystal and Vertex Models", (Internat. J. Modern Phys. A7(1992)449-484) by S-J. Kang et al. In this paper, we give a series of perfect crystals of $U_q(G_2^{(1)})$.

  6. Test results of the g-2 superconducting solenoid magnet system

    NARCIS (Netherlands)

    Bunce, G; Morse, WM; Benante, J; Cullen, MH; Danby, GT; Endo, K; Fedotovich, GV; Geller, J; Green, MA; Grossmann, A; GrossePerdckamp, M; Haeberlen, U; Hseuh, H; Hirabayashi, H; Hughes, VW; Jackson, JW; Jia, LX; Jungmann, K; Krienen, F; Larsen, R; Khazin, B; Kawall, D; Meng, W; Pai, C; Polk, T.; Prigl, R; Putlitz, GZ; Redin, S; Roberts, BL; Ryskulov, N; Semertzidas, Y; Shutt, R; Snydstrup, L; Tallerico, T; vonWalter, P; Woodle, K; Yamamoto, A

    The g-2 experiment dipole consists of a single 48 turn, 15.1 meter diameter outer solenoid and a pair of 24 turn inner solenoids, 13.4 meters in diameter. The inner solenoids are hooked in series and are run at a polarity that is opposite that of the outer solenoid, thus creating a dipole field in

  7. Performance Analysis for the New g-2 Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Stratakis, Diktys [Fermilab; Convery, Mary [Fermilab; Crmkovic, J. [RIKEN BNL; Froemming, Nathan [CENPA, Seattle; Johnstone, Carol [Fermilab; Johnstone, John [Fermilab; Korostelev, Maxim [Lancaster U.; Morgan, James [Fermilab; Morse, William [RIKEN BNL; Syphers, Michael [Fermilab; Tishchenko, Vladimir [RIKEN BNL

    2016-06-01

    The new g-2 experiment at Fermilab aims to measure the muon anomalous magnetic moment to a precision of ±0.14 ppm - a fourfold improvement over the 0.54 ppm precision obtained in the g-2 BNL E821experiment. Achieving this goal requires the delivery of highly polarized 3.094 GeV/c muons with a narrow ±0.5% Δp/p acceptance to the g-2 storage ring. In this study, we describe a muon capture and transport scheme that should meet this requirement. First, we present the conceptual design of our proposed scheme wherein we describe its basic features. Then, we detail its performance numerically by simulating the pion production in the (g-2) production target, the muon collection by the downstream beamline optics as well as the beam polarization and spin-momentum correlation up to the storage ring. The sensitivity in performance of our proposed channel against key parameters such as magnet apertures and magnet positioning errors is analyzed

  8. Fermilab Muon Campus g-2 Cryogenic Distribution Remote Control System

    Energy Technology Data Exchange (ETDEWEB)

    Pei, L.; Theilacker, J.; Klebaner, A.; Soyars, W.; Bossert, R.

    2015-11-05

    The Muon Campus (MC) is able to measure Muon g-2 with high precision and comparing its value to the theoretical prediction. The MC has four 300 KW screw compressors and four liquid helium refrigerators. The centerpiece of the Muon g-2 experiment at Fermilab is a large, 50-foot-diameter superconducting muon storage ring. This one-of-a-kind ring, made of steel, aluminum and superconducting wire, was built for the previous g-2 experiment at Brookhaven. Due to each subsystem has to be far away from each other and be placed in the distant location, therefore, Siemens Process Control System PCS7-400, Automation Direct DL205 & DL05 PLC, Synoptic and Fermilab ACNET HMI are the ideal choices as the MC g-2 cryogenic distribution real-time and on-Line remote control system. This paper presents a method which has been successfully used by many Fermilab distribution cryogenic real-time and On-Line remote control systems.

  9. FEI Titan G2 60-300 HOLO

    Directory of Open Access Journals (Sweden)

    Chris Boothroyd

    2016-02-01

    Full Text Available The FEI Titan G2 60-300 HOLO is a unique fourth generation transmission electron microscope, which has been specifically designed for the investigation of electromagnetic fields of materials using off-axis electron holography. It has a Lorentz lens to allow magnetic field free imaging plus two electron biprisms, which in combination enable more uniform holographic fringes to be used. The instrument also has an ultra-wide objective lens pole piece gap which is ideal for in situ experiments. For these purposes, the FEI Titan G2 60-300 HOLO is equipped with a Schottky type high-brightness electron gun (FEI X-FEG, an image Cs corrector (CEOS, a post-column energy filter system (Gatan Tridiem 865 ER as well as a 4 megapixel CCD system (Gatan UltraScan 1000 XP. Typical examples of use and technical specifications for the instrument are given below.

  10. A supermembrane with central charges on a G2 manifold

    Energy Technology Data Exchange (ETDEWEB)

    Belhaj, A; Segui, A [Departamento de Fisica Teorica, Universidad de Zaragoza, 12, Pedro Cerbuna, 50009 Zaragoza (Spain); Moral, M P Garcia del [Dipartimento di Fisica Teorica, Universita di Torino and INFN-Sezione di Torino, Via P Giuria 1, I-10125 Torino (Italy); Restuccia, A [Max-Planck-Institut fuer Gravitationphysik, Albert-Einstein-Institut, Muelenberg 1, D-14476 Potsdam (Germany); Veiro, J P [Departamento de Matematicas Puras y Aplicadas, Universidad Simon BolIvar, Apartado 89000, Caracas 1080-A (Venezuela, Bolivarian Republic of)], E-mail: belhaj@unizar.es, E-mail: garcia@to.infn.it, E-mail: restucci@aei.mpg.de, E-mail: arestu@usb.ve, E-mail: segui@unizar.es, E-mail: pierre@ma.usb.ve

    2009-08-14

    We construct an 11D supermembrane with topological central charges induced through an irreducible winding on a G2 manifold realized from the T{sup 7}/Z{sup 3}{sub 2} orbifold construction. The Hamiltonian H of the theory on a T{sup 7} target has a discrete spectrum. Within the discrete symmetries of H associated with large diffeomorphisms, the Z{sub 2} x Z{sub 2} x Z{sub 2} group of automorphisms of the quaternionic subspaces preserving the octonionic structure is relevant. By performing the corresponding identification on the target space, the supermembrane may be formulated on a G2 manifold, preserving the discreteness of its supersymmetric spectrum. The corresponding 4D low energy effective field theory has N = 1 supersymmetry.

  11. Massive vectors and loop observables: the $g-2$ case

    CERN Document Server

    Biggio, Carla; Di Luzio, Luca; Ridolfi, Giovanni

    2016-01-01

    We discuss the use of massive vectors for the interpretation of some recent experimental anomalies. In order for loop observables, such as for example the muon $g-2$, to be finite (and hence to be predictable in terms of a renormalizable Lagrangian) the massive vector must be embedded into a spontaneously broken extended gauge symmetry. The latter, however, typically imposes strong constraints on the mass of the new vector boson and for the muon $g-2$ it basically rules out, barring the case of abelian gauge extensions, the explanation of the discrepancy in terms of a single vector extension of the standard model. We finally comment on the use of massive vectors for $B$-meson decay and di-photon anomalies.

  12. REPRESENTATIONS OF AFFINE HECKE ALGEBRAS OF TYPE G2

    Institute of Scientific and Technical Information of China (English)

    Xi Nanhua

    2009-01-01

    Let k be a field and q a nonzero element in k such that the square roots of q are in k.We use Hq to denote an affine Hecke algebra over k of type G2 with parameter q.The purpose of this paper is to study representations of Hq by using based rings of two-sided cells of an affine Weyl group W of type G2.We shall give the classification of irreducible representations of Hq.We also remark that a calculation in [11] actually shows that Theorem 2 in [1] needs a modification, a fact is known to Grojnowski and Tanisaki long time ago.In this paper we also show an interesting relation between Hq and an Hecke algebra corresponding to a certain Coxeter group.Apparently the idea in this paper works for all affine Weyl groups, but that is the theme of another paper.

  13. Experimental Results and Theoretical Developments of Muon g-2

    CERN Document Server

    Deng, H; Bennett, G W; Bousquet, B; Brown, H N; Bunce, G; Carey, R M; Cushman, P; Danby, G T; Debevec, P T; Deile, M; Dhawan, S K; Druzhinin, V P; Duong, L; Farley, F J M; Fedotovich, G V; Gray, F E; Grigoriev, D; Grosse-Perdekamp, M; Grossmann, A; Hare, M; Hertzog, D W; Huang, X; Hughes, V W; Iwasaki, M; Jungmann, Klaus; Kawall, D; Khazin, B I; Krienen, F; Kronkvist, I J; Lam, A; Larsen, R; Lee, Y Y; Logashenko, I; McNabb, R; Meng, W; Miller, J P; Morse, W M; Nikas, D; Onderwater, Gerco; Orlov, Y; Ozben; Paley, J M; Peng, Q; Polly, C C; Pretz, J; Prigl, R; zu Putlitz, Gisbert; Qian, T; Redin, S I; Rind, O; Roberts, B L; Ryskulov, N M; Semertzidis, Y K; Shagin, P; Shatunov, Yu M; Sichtermann, E P; Solodov, E; Sossong, M; Sulak, L R; Trofimov, A; Von Walter, P; Yamamoto, A

    2004-01-01

    The anomalous magnetic moments of both positive and negative muons are measured to the precision of 0.7 parts per million. Two values are in good agreement. The standard model calculations of muon g-2 are under further studies, especially the descrepancies between $e^+e^-$ and $\\tau$ data. The differences between experimental result and the standard model calculations are $2.4\\sigma$ for $e^+e^-$ data and $0.9\\sigma$ for $\\tau$ data.

  14. Supergravity corrections to $(g-2)_l$ in differential renormalization

    CERN Document Server

    del Águila, F; Muñoz-Tàpia, R; Pérez-Victoria, M

    1997-01-01

    The method of differential renormalization is extended to the calculati= on of the one-loop graviton and gravitino corrections to $(g-2)_l$ in unbroken supergravity. Rewriting the singular contributions of all the diagrams in= terms of only one singular function, U(1) gauge invariance and supersymmetry ar= e preserved. We compare this calculation with previous ones which made use = of momentum space regularization (renormalization) methods.

  15. Interrelationship among g-2, EDMs and cLFV

    Science.gov (United States)

    Paradisi, Paride

    2014-03-01

    We summarize the status of charged lepton flavor violation (cLFV) in models beyond the SM. We stress that the current experimental bounds on cLFV processes are already constraining new physics (NP) scenarios more than the direct bounds from the LHC. On the other hand, the interrelationship among leptonic g-2, EDMs and cLFV will turn out to be of outmost importance to disentangle among different NP scenarios.

  16. Conjectures on counting associative 3-folds in $G_2$-manifolds

    CERN Document Server

    Joyce, Dominic

    2016-01-01

    There is a strong analogy between compact, torsion-free $G_2$-manifolds $(X,\\varphi,*\\varphi)$ and Calabi-Yau 3-folds $(Y,J,g,\\omega)$. We can also generalize $(X,\\varphi,*\\varphi)$ to 'tamed almost $G_2$-manifolds' $(X,\\varphi,\\psi)$, where we compare $\\varphi$ with $\\omega$ and $\\psi$ with $J$. Associative 3-folds in $X$, a special kind of minimal submanifold, are analogous to $J$-holomorphic curves in $Y$. Several areas of Symplectic Geometry -- Gromov-Witten theory, Quantum Cohomology, Lagrangian Floer cohomology, Fukaya categories -- are built using 'counts' of moduli spaces of $J$-holomorphic curves in $Y$, but give an answer depending only on the symplectic manifold $(Y,\\omega)$, not on the (almost) complex structure $J$. We investigate whether it may be possible to define interesting invariants of tamed almost $G_2$-manifolds $(X,\\varphi,\\psi)$ by 'counting' compact associative 3-folds $N\\subset X$, such that the invariants depend only on $\\varphi$, and are independent of the 4-form $\\psi$ used to def...

  17. Muon g - 2 in MSSM gauge mediation revisited

    Science.gov (United States)

    Yanagida, Tsutomu T.; Yokozaki, Norimi

    2017-09-01

    The Higgs boson of 125 GeV requires large stop masses, leading to the large μ-parameter in most cases of gauge mediation. On the other hand, the explanation for the muon g - 2 anomaly needs small slepton and neutralino/chargino masses. Such disparity in masses may be obtained from a mass splitting of colored and non-colored messenger fields. However, even if the required small slepton and neutralino/chargino masses are realized, all parameter regions consistent with the muon g - 2 are excluded by the recent updated ATLAS result on the wino search in the case that the messenger fields are in 5 + 5 bar representations of SU (5). It is also revealed that the messenger fields in 10 + 10 ‾ or 24 representation can not explain the muon g - 2 anomaly. We show, giving a simple example model, that the above confliction is solved if there is an additional contribution to the Higgs soft mass which makes the μ-parameter small. We also show that the required Higgs B-term for the electroweak symmetry breaking is consistently generated by radiative corrections from gaugino loops.

  18. Infinitesimal moduli of G2 holonomy manifolds with instanton bundles

    Science.gov (United States)

    de la Ossa, Xenia; Larfors, Magdalena; Svanes, Eirik E.

    2016-11-01

    We describe the infinitesimal moduli space of pairs ( Y, V) where Y is a manifold with G 2 holonomy, and V is a vector bundle on Y with an instanton connection. These structures arise in connection to the moduli space of heterotic string compactifications on compact and non-compact seven dimensional spaces, e.g. domain walls. Employing the canonical G 2 cohomology developed by Reyes-Carrión and Fernández and Ugarte, we show that the moduli space decomposes into the sum of the bundle moduli {H}_{{overset{ěe }{d}}_A}^1(Y,End(V)) plus the moduli of the G 2 structure preserving the instanton condition. The latter piece is contained in {H}_{overset{ěe }{d}θ}^1(Y,TY) , and is given by the kernel of a map overset{ěe }{F} which generalises the concept of the Atiyah map for holomorphic bundles on complex manifolds to the case at hand. In fact, the map overset{ěe }{F} is given in terms of the curvature of the bundle and maps {H}_{overset{ěe }{d}θ}^1(Y,TY) into {H}_{{overset{ěe }{d}}_A}^2(Y,End(V)) , and moreover can be used to define a cohomology on an extension bundle of TY by End( V). We comment further on the resemblance with the holomorphic Atiyah algebroid and connect the story to physics, in particular to heterotic compactifications on ( Y, V) when α' = 0.

  19. Revised value of the eighth-order electron g-2

    CERN Document Server

    Aoyama, T; Kinoshita, T; Nio, M

    2007-01-01

    The contribution to the eighth-order anomalous magnetic moment (g-2) of the electron from a set of diagrams without closed lepton loops is recalculated using a new FORTRAN code generated by an automatic code generator. Comparing the contributions of individual diagrams of old and new calculations, we found an inconsistency in the old treatment of infrared subtraction terms in two diagrams. Correcting this error leads to the revised value -1.9144 (35) (alpha/pi)^4 for the eighth-order term. This theoretical change induces the shift of the inverse of the fine structure constant by -6.41180(73)x10^{-7}.

  20. Status of the BNL Muon g-2 Experiment

    CERN Document Server

    Prigl, R; Bunce, G M; Carey, R M; Cushman, P B; Danby, G T; Debevec, P T; Deng, H; Deninger, W J; Dhawan, S K; Druzhinin, V P; Duong, L; Earle, W; Efstathiadis, E F; Farley, Francis J M; Fedotovich, G V; Giron, S; Gray, F; Grosse-Perdekamp, M; Grossmann, A; Haeberlen, U; Hare, M; Hazen, E S; Hertzog, D W; Hughes, V W; Iwasaki, M; Jungmann, Klaus; Kawall, D; Kawamura, M; Khazin, B I; Kindem, J; Krienen, F; Kronkvist, I J; Larsen, R; Lee, Y Y; Liu, W; Logashenko, I B; McNabb, R; Meng, W; Mi, J L; Miller, J P; Morse, W M; Neumayer, P; Nikas, D; Onderwater, Gerco; Orlov, Yu F; Ozben, C; Paley, J M; Pai, C; Polly, C; Pretz, J; zu Putlitz, Gisbert; Redin, S I; Rind, O; Roberts, B L; Ryskulov, N M; Sedykh, S N; Semertzidis, Y K; Shatunov, Yu M; Sichtermann, E P; Solodov, E P; Sossong, M; Steinmetz, A; Sulak, Lawrence R; Tanaka, M; Timmermans, C; Trofimov, A V; Urner, D; Warburton, D; Winn, D; Yamamoto, A; Zimmerman, D

    2000-01-01

    The muon g-2 experiment at Brookhaven has been taking data since 1997. Analyses of the data taken in 1997 and 1998, which include about 2% of the data taken so far, have improved the experimental accuracy in the muon anomalous magnetic moment to a(mu,expt) = 1 165 921(5) x 10**(-9) (4 ppm). The value agrees with standard theory. Analysis of the 1999 data, about 25% of the existing data set, is nearing completion and analysis of the 2000 data has started. The experiment is preparing for another major data taking run, this time storing negative instead of positive muon beams.

  1. Discrete Fourier Analysis and Chebyshev Polynomials with G2 Group

    Directory of Open Access Journals (Sweden)

    Huiyuan Li

    2012-10-01

    Full Text Available The discrete Fourier analysis on the 30°-60°-90° triangle is deduced from the corresponding results on the regular hexagon by considering functions invariant under the group G2, which leads to the definition of four families generalized Chebyshev polynomials. The study of these polynomials leads to a Sturm-Liouville eigenvalue problem that contains two parameters, whose solutions are analogues of the Jacobi polynomials. Under a concept of m-degree and by introducing a new ordering among monomials, these polynomials are shown to share properties of the ordinary orthogonal polynomials. In particular, their common zeros generate cubature rules of Gauss type.

  2. General Metrics of G_2 Holonomy and Contraction Limits

    CERN Document Server

    Chong, Z W; Gibbons, G W; Lü, H; Pope, C N; Wagner, P

    2002-01-01

    We obtain first-order equations for G_2 holonomy of a wide class of metrics with S^3\\times S^3 principal orbits and SU(2)\\times SU(2) isometry, using a method recently introduced by Hitchin. The new construction extends previous results, and encompasses all previously-obtained first-order systems for such metrics. We also study various group contractions of the principal orbits, focusing on cases where one of the S^3 factors is subjected to an Abelian, Heisenberg or Euclidean-group contraction. In the Abelian contraction, we recover some recently-constructed G_2 metrics with S^3\\times T^3 principal orbits. We obtain explicit solutions of these contracted equations in cases where there is an additional U(1) isometry. We also demonstrate that the only solutions of the full system with S^3\\times T^3 principal orbits that are complete and non-singular are either flat R^4 times T^3, or else the direct product of Eguchi-Hanson and T^3, which is asymptotic to R^4/Z_2\\times T^3. These examples are in accord with a ge...

  3. Split Sfermion Families, Yukawa Unification and Muon g-2

    CERN Document Server

    Ajaib, M Adeel; Shafi, Qaisar; Un, Cem Salih

    2014-01-01

    We consider two distinct classes of Yukawa unified supersymmetric SO(10) models with non-universal and universal soft supersymmetry breaking (SSB) gaugino masses at M_{\\rm GUT}. In both cases, we assume that the third family SSB sfermion masses at M_{\\rm GUT} are different from the corresponding sfermion masses of the first two families (which are equal). For the SO(10) model with essentially arbitrary (non-universal) gaugino masses at M_{\\rm GUT}, it is shown that t-b-\\tau Yukawa coupling unification is compatible, among other things, with the 125 GeV Higgs boson mass, the WMAP relic dark matter density, and with the resolution of the apparent muon g-2 anomaly. The colored sparticles in this case all turn out to be quite heavy, of order 5 TeV or more, but the sleptons (smuon and stau) can be very light, of order 200 GeV or so. For the SO(10) model with universal gaugino masses and NUHM2 boundary conditions, the muon g-2 anomaly cannot be resolved. However, the gluino in this class of models is not too heavy,...

  4. Inferring Toxicological Responses of HepG2 Cells from ...

    Science.gov (United States)

    Understanding the dynamic perturbation of cell states by chemicals can aid in for predicting their adverse effects. High-content imaging (HCI) was used to measure the state of HepG2 cells over three time points (1, 24, and 72 h) in response to 976 ToxCast chemicals for 10 different concentrations (0.39-200µM). Cell state was characterized by p53 activation (p53), c-Jun activation (SK), phospho-Histone H2A.x (OS), phospho-Histone H3 (MA), alpha tubulin (Mt), mitochondrial membrane potential (MMP), mitochondrial mass (MM), cell cycle arrest (CCA), nuclear size (NS) and cell number (CN). Dynamic cell state perturbations due to each chemical concentration were utilized to infer coarse-grained dependencies between cellular functions as Boolean networks (BNs). BNs were inferred from data in two steps. First, the data for each state variable were discretized into changed/active (> 1 standard deviation), and unchanged/inactive values. Second, the discretized data were used to learn Boolean relationships between variables. In our case, a BN is a wiring diagram between nodes that represent 10 previously described observable phenotypes. Functional relationships between nodes were represented as Boolean functions. We found that inferred BN show that HepG2 cell response is chemical and concentration specific. We observed presence of both point and cycle BN attractors. In addition, there are instances where Boolean functions were not found. We believe that this may be either

  5. The TSO Logic and G2 Software Product

    Science.gov (United States)

    Davis, Derrick D.

    2014-01-01

    This internship assignment for spring 2014 was at John F. Kennedy Space Center (KSC), in NASAs Engineering and Technology (NE) group in support of the Control and Data Systems Division (NE-C) within the Systems Hardware Engineering Branch. (NEC-4) The primary focus was in system integration and benchmarking utilizing two separate computer software products. The first half of this 2014 internship is spent in assisting NE-C4s Electronics and Embedded Systems Engineer, Kelvin Ruiz and fellow intern Scott Ditto with the evaluation of a newly piece of software, called G2. Its developed by the Gensym Corporation and introduced to the group as a tool used in monitoring launch environments. All fellow interns and employees of the G2 group have been working together in order to better understand the significance of the G2 application and how KSC can benefit from its capabilities. The second stage of this Spring project is to assist with an ongoing integration of a benchmarking tool, developed by a group of engineers from a Canadian based organization known as TSO Logic. Guided by NE-C4s Computer Engineer, Allen Villorin, NASA 2014 interns put forth great effort in helping to integrate TSOs software into the Spaceport Processing Systems Development Laboratory (SPSDL) for further testing and evaluating. The TSO Logic group claims that their software is designed for, monitoring and reducing energy consumption at in-house server farms and large data centers, allows data centers to control the power state of servers, without impacting availability or performance and without changes to infrastructure and the focus of the assignment is to test this theory. TSOs Aaron Rallo Founder and CEO, and Chris Tivel CTO, both came to KSC to assist with the installation of their software in the SPSDL laboratory. TSOs software is installed onto 24 individual workstations running three different operating systems. The workstations were divided into three groups of 8 with each group having its

  6. Status of the g-2 experiment at BNL

    CERN Document Server

    Grosse-Perdekamp, M; Brown, D H; Carey, R M; Earle, W; Efstathiadis, E F; Hare, M; Hazen, E S; Hughes, B J; Krienen, F; Logashenko, I B; Miller, J P; Monich, V A; Ouyang, J; Rind, O; Roberts, B L; Sulak, Lawrence R; Trofimov, A V; Varner, G S; Worstell, W A; Benante, J; Brown, H N; Bunce, G M; Cullen, J; Danby, G T; Geller, J; Hseuh, H C; Jackson, J W; Jia, L; Kochis, S; Larsen, R; Lee, Y Y; Mapes, M; Meng, W; Morse, W M; Pai, C; Pearson, C; Polk, I; Prigl, R; Rankowitz, S; Sandberg, J; Semertzidis, Y K; Shutt, R P; Snydstrup, L; Soukas, A; Stillman, A; Tanaka, T; Tallerico, T; Toldo, F; Von Lintig, R D; Warburton, D; Woodle, K; Chertovskikh, A; Druzhinin, V P; Fedotovich, G V; Grigoriev, D N; Golubev, V B; Khazin, B I; Maskimov, A; Merzliakov, Yu; Ryskulov, N M; Serednyakov, S I; Shatunov, Yu M; Solodov, E P; Orlov, Yu F; Winn, D; Gerhäuser, J; Grossmann, A; Jungmann, Klaus; Von Walter, P; zu Putlitz, Gisbert; Bunker, B D; Debevec, P T; Deninger, W J; Hertzog, D W; Jones, T; Poly, C; Sedykh, S N; Urner, D; Haeberlen, U; Endo, KI; Hirabayashi, H; Kurokawa, S; Yamamoto, A; Green, M A; Cushman, P B; Duong, L; Giron, S; Kindem, J; McNabb, R; Miller, D; Timmermans, C; Zimmerman, D; Mizumachi, Y; Iwasaki, M; Ahn, H E; Deng, H; Dhawan, S K; Disco, A; Farley, Francis J M; Fei, X; Hughes, V W; Kawall, D; Pretz, J; Redin, S I

    1999-01-01

    The muon g-2 experiment at Brookhaven has successfully completed two exploratory runs using pion injection and direct muon injection for checkout and initial data taking. The main components of the experiment, which include the pion beam line, the superconducting storage ring and inflector magnets, the muon kicker and the lead scintillating fiber calorimeters have been satisfactorily commissioned. First results on the anomalous magnetic moment of the positive muon from pion injection are in good agreement with previous experimental results for a/sub mu +/ and a/sub mu -/ from CERN and of comparable accuracy (13 ppm). Analysis of the 1998 muon injection run is in progress and expected to improve the precision to about 4 ppm. A first production run is scheduled for January 1999 with the goal of reaching the 1 ppm error level. (16 refs).

  7. Enhanced G2 chromatid radiosensitivity in dyskeratosis congenita fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    DeBauche, D.M.; Pai, G.S.; Stanley, W.S. (Medical Univ. of South Carolina, Charleston (USA))

    1990-02-01

    Dyskeratosis congenita (DC) is an inherited disorder characterized by reticular pigmentation of the skin, dystrophic nails, mucosal leukoplakia, and a predisposition to cancer in early adult life. In the majority of cases, DC is an X-linked recessive trait. However, one or more autosomal form(s) of DC may exist. Although excessive spontaneous chromatid breakage has been reported in DC, it is not a consistent cytological marker for this disorder. We examined the frequency and specificity of X-irradiation-induced G2 chromatid breakage in fibroblasts from three unrelated DC patients (two males and one female). Metaphase cells from DC patients had significantly more chromatid breaks (16-18-fold and 17-26-fold at 50 and 100 rad X-irradiation, respectively) and chromatid gaps (10-12-fold and 6-7-fold at 50 and 100 rad, respectively) than those from two different controls. Analysis of banded chromosomes revealed a nonrandom distribution of chromatid aberrations in DC but not in controls, a distribution corresponding to some of the known breakpoints for cancer-specific rearrangements, constitutive fragile sites, and/or loci for cellular proto-oncogenes. The significance of this finding for cancer predisposition in DC patients is uncertain, but the increased susceptibility of X-irradiation-induced chromatid breakage may serve as a cellular marker of diagnostic value.

  8. Corps G 2 Staff Competencies: A Desert Storm Case Study

    Science.gov (United States)

    2017-06-09

    Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202...Approved for Public Release; Distribution is Unlimited 13. SUPPLEMENTARY NOTES An Army Warfighting Challenge asks what Soldier, leader , and unit...Member Jeffrey D. Vordermark, M.A. Accepted this 9th day of June 2017 by: , Director , Graduate Degree Programs Prisco R. Hernandez

  9. Data of evolutionary structure change: 1AQFB-3G2GD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1AQFB-3G2GD 1AQF 3G2G B D IQTQQLHAAMADTFLEHMCRLDIDSAPITARNTGIICTI...ISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMIIGRCNRAGKPVICATQMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGD...HQTARQAHLYRGIFPVVCKDPVQEAWAEDVDLRVNLAMNVGKARGFFKKGDVVIVLTGWRPGSGFTNTMRVVPVP -QTQQLHAAMADTFLEHMC...VSEKDIQDLKFGVEQDVDMVFASFIRKASDVHEVRKVLGEKGKNIKIISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMMIGRCNRAGKPVICAT...QMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGDYPLEAVRMQHLIAREAEAAIYHLQLFEELRRLAPITSDPT

  10. Complete Tenth-Order QED Contribution to the Muon g-2

    CERN Document Server

    Aoyama, Tatsumi; Kinoshita, Toichiro; Nio, Makiko

    2012-01-01

    We report the result of our calculation of the complete tenth-order QED terms of the muon g-2. Our result is a_\\mu^{(10)} = 753.29 (1.04) in units of (\\alpha/\\pi)^5, which is about 4.5 s.d. larger than the leading-logarithmic estimate 663 (20). We also improved the precision of the eighth-order QED term of a_\\mu, obtaining a_\\mu^{(8)} = 130.8794 (63) in units of (\\alpha/\\pi)^4. Using the best non-QED value of \\alpha, we obtain the standard model prediction a_\\mu(SM) = 116 591 840 (59) \\times 10^{-11}, to be compared with the measured value a_\\mu(exp) = 116 592 089 (63) \\times 10^{-11}. The difference a_\\mu(exp) - a_\\mu(SM) = 240 (87) \\times 10^{-11} is about 2.8 s.d.

  11. Hepatoma cell line HepG2.2.15 demonstrates distinct biological features compared with parental HepG2

    Institute of Scientific and Technical Information of China (English)

    Ran Zhao; Tian-Zhen Wang; Dan Kong; Lei Zhang; Hong-Xue Meng; Yang Jiang; Yi-Qi Wu; Zu-Xi Yu; Xiao-Ming Jin

    2011-01-01

    AIM: To investigate the biological features of hepatitis B virus (HBV)-transfected HepG2.2.15 cells. METHODS: The cell ultrastructure, cell cycle and apop-tosis, and the abilities of proliferation and invasion of HBV-transfected HepG2.2.15 and the parent HepG2 cells were examined by electron microscopy, flow cytometry, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and trans-well assay. Oncogenicity of the two cell lines was compared via subcutaneous injection and orthotopic injection or implantation in nude mice, and the pathological analysis of tumor formation was performed. Two cytoskeletal proteins were detected by Western blotting.RESULTS: Compared with HepG2 cells, HepG2.2.15 cells showed organelle degeneration and filopodia disappear-ance under electron microscope. HepG2.2.15 cells pro-liferated and migrated slowly in vitro, and hardly formed tumor and lung metastasis in nude mice. Flow cytom-etry showed that the majority of HepG2.2.15 cells were arrested in G1 phase, and apoptosis was minor in both cell lines. Furthermore, the levels of cytoskeletal pro-teins F-actin and Ezrin were decreased in HepG2.2.15 cells.CONCLUSION: HepG2.2.15 cells demonstrated a low-er proliferation and invasion ability than the HepG2 cells due to HBV transfection.

  12. The Oscillator Strengths of H2+, 1s\\sigma_{g}-2p\\sigma_{u}, 1s\\sigma_{g}-2p\\pi_{u}

    CERN Document Server

    Tsogbayar, Ts

    2010-01-01

    The oscillator strengths of the $H^+_2$ molecular ion, $1s\\sigma_{g}-2p\\sigma_{u}$, $1s\\sigma_{g}-2p\\pi_{u}$ are calculated within the Born-Oppenheimer approximation. The variational expansion with randomly chosen exponents has been used for numerical studies. The oscillator strengths obtained for the transitions $1s\\sigma_{g}-2p\\sigma_{u}$, $1s\\sigma_{g}-2p\\pi_{u}$ of $H^+_2$ are accurate up to ten significant digits. Results are given for the internuclear distances between 0.10 and 20.0 a.u.

  13. Data of evolutionary structure change: 1E0UC-3G2GD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1E0UC-3G2GD 1E0U 3G2G C D ----------------------------MKKTKIVCTIG...PKTESEEMLAKMLDAGMNVMRLNFSHGDYAEHGQRIQNLRNVMSKT------GKTAAILLDTKGPEIRTMKLEGGNDVSLKAGQTFTFTTDKSVI--GNSEMVAVTYE...GFTTDLSVGNTVLVDDGLIGMEVTAIEGNKVICKVLNNGDLGENKGVNLPGVSIALPALAEKDKQDLIFGCEQGVDFVAASFIRKRSDVIEIREHLKAHGGENIHIIS...KIENQEGLNNFDEILEASDGIMVARGDLGVEIPVEEVIFAQKMMIEKCIRALKVVITATMMLDSMIKNPRPTRAEAGDVAN...TAHQLVLSKGVVPQLV--KEITSTDDFYR----LGKELALQSGLAHKGDVVVMVSGALVPSGTTNTASVHVL- QTQQLHAAMADTFLEHMCRLD

  14. Data of evolutionary structure change: 1F3WA-3G2GD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1F3WA-3G2GD 1F3W 3G2G A D IQTQQLHAAMADTFLEHMCRLDIDSAPITARNTGIICTI...ISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMIIGRCNRAGKPVICATQMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGD...HQTARQAHLYRGIFPVVCKDPVQEAWAEDVDLRVNLAMNVGKARGFFKKGDVVIVLTGWRPGSGFTNTMRVVPVP -QTQQLHAAMADTFLEHMC...VSEKDIQDLKFGVEQDVDMVFASFIRKASDVHEVRKVLGEKGKNIKIISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMMIGRCNRAGKPVICAT...QMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGDYPLEAVRMQHLIAREAEAAIYHLQLFEELRRLAPITSDPT

  15. Data of evolutionary structure change: 1F3XH-3G2GD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1F3XH-3G2GD 1F3X 3G2G H D IQTQQLHAAMADTFLEHMCRLDIDSAPITARNTGIICTI...ISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMIIGRCNRAGKPVICATQMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGD...HQTARQAHLYRGIFPVVCKDPVQEAWAEDVDLRVNLAMNVGKARGFFKKGDVVIVLTGWRPGSGFTNTMRVVPVP -QTQQLHAAMADTFLEHMC...VSEKDIQDLKFGVEQDVDMVFASFIRKASDVHEVRKVLGEKGKNIKIISKIENHEGVRRFDEILEASDGIMVARGDLGIEIPAEKVFLAQKMMIGRCNRAGKPVICAT...QMLESMIKKPRPTRAEGSDVANAVLDGADCIMLSGETAKGDYPLEAVRMQHLIAREAEAAIYHLQLFEELRRLAPITSDPT

  16. Alcohol Dehydrogenase 5 Is a Source of Formate for De Novo Purine Biosynthesis in HepG2 Cells.

    Science.gov (United States)

    Bae, Sajin; Chon, James; Field, Martha S; Stover, Patrick J

    2017-04-01

    Background: Formate provides one-carbon units for de novo purine and thymidylate (dTMP) synthesis and is produced via both folate-dependent and folate-independent pathways. Folate-independent pathways are mediated by cytosolic alcohol dehydrogenase 5 (ADH5) and mitochondrial aldehyde dehydrogenase 2 (ALDH2), which generate formate by oxidizing formaldehyde. Formate is a potential biomarker of B-vitamin-dependent one-carbon metabolism.Objective: This study investigated the contributions of ADH5 and ALDH2 to formate production and folate-dependent de novo purine and dTMP synthesis in HepG2 cells.Methods:ADH5 knockout and ALDH2 knockdown HepG2 cells were cultured in folate-deficient [0 nM (6S) 5-formyltetrahydrofolate] or folate-sufficient [25 nM (6S) 5-formyltetrahydrofolate] medium. Purine biosynthesis was quantified as the ratio of [(14)C]-formate to [(3)H]-hypoxanthine incorporated into genomic DNA, which indicates the contribution of the de novo purine synthesis pathway relative to salvage synthesis. dTMP synthesis was quantified as the ratio of [(14)C]-deoxyuridine to [(3)H]-thymidine incorporation into genomic DNA, which indicates the capacity of de novo dTMP synthesis relative to salvage synthesis.Results: The [(14)C]-formate-to-[(3)H]-hypoxanthine ratio was greater in ADH5 knockout than in wild-type HepG2 cells, under conditions of both folate deficiency (+30%; P HepG2 cells, indicating decreased use of exogenous formate, or increased endogenous formate synthesis, for de novo purine biosynthesis.Conclusions: In HepG2 cells, ADH5 is a source of formate for de novo purine biosynthesis, especially during folate deficiency when folate-dependent formate production is limited. Formate is also shown to be limiting in the growth of HepG2 cells. © 2017 American Society for Nutrition.

  17. Effects of PRELI in Oxidative-Stressed HepG2 Cells.

    Science.gov (United States)

    Kim, Bo Yong; Cho, Min Ho; Kim, Kyung Joo; Cho, Kyung Jin; Kim, Suhng Wook; Kim, Hyun Sook; Jung, Woon-Won; Lee, Boo Hyung; Lee, Bong Hee; Lee, Seung Gwan

    2015-01-01

    Protein of relevant evolutionary and lymphoid interest (PRELI) is known for preventing apoptosis by mediating intramitochondrial transport of phosphatidic acid. However, the role of PRELI remains unclear. This study has demonstrated functions of PRELI through PRELI-knockdown in hepatocellular carcinoma (HepG2) cells exposed to oxidative stress by hydrogen peroxide. Results show that PRELI has three functions in HepG2 cells with regard to oxidative stress. First, PRELI affects expressional regulation of SOD-1 and caspase-3 genes in HepG2 cells. PRELI knockdown HepG2 cells have shown up-regulation of caspase-3 and down-regulation of SOD-1. Second, PRELI suppresses mitochondrial apoptosis in HepG2 cells. Fluorescence intensity related to mitochondrial apoptosis in PRELI-knockdown HepG2 cells increased more than two-fold compared to normal HepG2 cells. Third, PRELI suppresses senescence of HepG2 cells with oxidative stress. PRELI knockdown HepG2 cells showed higher levels of senescence than normal HepG2 cells. These results suggest that PRELI is a crucial protein in the suppression of apoptosis in HepG2 cells in response to oxidative stress. © 2015 by the Association of Clinical Scientists, Inc.

  18. [Observation of radiobiological characteristics in a HepG2 cell line with mitochondrial DNA deletion].

    Science.gov (United States)

    Sun, Hengwen; Pan, Yi; Zeng, Zijun; Fang, Liangyi; Zhang, Hongdan; Xie, Songxi; Li, Weixiong; Xu, Jiabin

    2015-06-01

    To study the radiobiological characteristics of a HepG2 cell line with mitochondrial DNA (mtDNA) deletion. HepG2 cells were cultured in a medium containing ethidium bromide, acetylformic acid and uracil. The HepG2 cell line with mtDNA deletion (ρ(0)HepG2 cells) were acquired after 30 subcultures by limited dilution cloning. The cell survival was then observed in the absence of acetylformic acid and uracil, and the total mtDNA deletion in the cells was confirmed by PCR. The radiosensitivity of HepG2 and ρ(0)HepG2 cells was evaluated by exposure to gradient doses of 6 MV X ray irradiation. The cell apoptosis was assessed following a 2 Gy X-ray exposure with Hochest33342 staining, and the invasiveness of ρ(0)HepG2 cells was measured by Transwell assay. HepG2 cells could survive 30 subcultures in the presence of ethidium bromide, and massive cell death occurred after removal of acetylformic acid and uracil from the medium. PCR confirmed total mtDNA deletion from ρ(0)HepG2 cells, whose α/β value was significantly lower than that of HepG2 cells. ρ(0)Hep-G2 cells showed an obviously lowered cell apoptosis rate following X-ray exposure with enhanced cell invasiveness. HepG2 cells can be induced by ethidium bromide into ρ(0)HepG2 cells with an increased radiation resistance, anti-apoptosis ability and cell invasiveness.

  19. Sodium cantharidinate induces HepG2 cell apoptosis through LC3 autophagy pathway.

    Science.gov (United States)

    Tao, Ran; Sun, Wen-Yi; Yu, De-Hai; Qiu, Wei; Yan, Wei-Qun; Ding, Yan-Hua; Wang, Guang-Yi; Li, Hai-Jun

    2017-08-01

    The function of sodium cantharidinate on inducing hepatocellular carcinoma cell apoptosis was investigated for the first time. Sodium cantharidinate inhibits HepG2 cell growth mainly by LC3 autophagy pathway. MTT results show that sodium cantharidinate effectively inhibits the proliferation of HepG2 cells in a dose- and time-dependent manner and induce cell apoptosis by caspase-3 activity. The further western blotting and FACS detection show that sodium cantharidinate initiates HepG2 cell autophagy program by LC3 pathway. Autophagy-specific inhibitor 3-MA reduce sodium cantharidinate-induced caspase-3 activity and HepG2 cell apoptosis. Silence of the LC3 gene in HepG2 cell lines also reduce sodium cantharidinate-induced cell apoptosis. Collectively, our data indicate that sodium cantharidinate induces HepG2 cell apoptosis through LC3 autophagy pathway. Sodium cantharidinate has potential for development as a new drug for treatment of human HCC.

  20. Study on preliminary mechanism of apoptosis in HepG-2 by CSA

    Institute of Scientific and Technical Information of China (English)

    YU Lei; MU Ke; WANG Wei; CUI Rong-tian; JI Yu-bin; ZOU Xiang

    2008-01-01

    t Objective To study on the mechanism of killing and apoptosis inducing effect of total alkaloid in the CSA(Capparis spinosa L. alkaloid, CSA)on human hepatoearcinoma cell Line HepG-2. Methods The killing effect of the CSA on human hepatoeareinoma cell Line HepG-2 was measured by MTT method. Morphological observation of the HepG-2 cells was completed by fluorescence microscope. The apoptosis indueing effect and changing of mitoehondria membrane potential of the CSA on the HepG-2 cells were measured by flow cytometry. In addition, effect of intraeellular Ca2+ level of the CSA on the HepG-2 cells was studied by laser confocal microscope. Results The CSA has obvious cytotoxicity on the HepG-2 and seems to be dose-dependent, and its IC50 value is 162.4 μg·mL-1. The HepG-2 cells have characteristic morphologic changes of apoptosis by the function of CSA, and the apoptosis percentage is higher than the natural one. The progress of cells cycle from S phase to G2 phase has been blocked, and the mitochondria membrane potential is markedly decreased, and the intraecllular Ca2+ level is increased by the function of CSA. Conclusions The CSA has obviously killing and apoptosis inducing effect on human hepatoearcinoma cell Line HepG-2 by the mechanism of decreasing the mitoehondria membrane potential and increasing the intracellular Ca2+ level.

  1. Data Acquisition with GPUs: The DAQ for the Muon $g$-$2$ Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Gohn, W. [Kentucky U.

    2016-11-15

    Graphical Processing Units (GPUs) have recently become a valuable computing tool for the acquisition of data at high rates and for a relatively low cost. The devices work by parallelizing the code into thousands of threads, each executing a simple process, such as identifying pulses from a waveform digitizer. The CUDA programming library can be used to effectively write code to parallelize such tasks on Nvidia GPUs, providing a significant upgrade in performance over CPU based acquisition systems. The muon $g$-$2$ experiment at Fermilab is heavily relying on GPUs to process its data. The data acquisition system for this experiment must have the ability to create deadtime-free records from 700 $\\mu$s muon spills at a raw data rate 18 GB per second. Data will be collected using 1296 channels of $\\mu$TCA-based 800 MSPS, 12 bit waveform digitizers and processed in a layered array of networked commodity processors with 24 GPUs working in parallel to perform a fast recording of the muon decays during the spill. The described data acquisition system is currently being constructed, and will be fully operational before the start of the experiment in 2017.

  2. Data Acquisition with GPUs: The DAQ for the Muon $g$-$2$ Experiment at Fermilab

    CERN Document Server

    Gohn, W

    2016-01-01

    Graphical Processing Units (GPUs) have recently become a valuable computing tool for the acquisition of data at high rates and for a relatively low cost. The devices work by parallelizing the code into thousands of threads, each executing a simple process, such as identifying pulses from a waveform digitizer. The CUDA programming library can be used to effectively write code to parallelize such tasks on Nvidia GPUs, providing a significant upgrade in performance over CPU based acquisition systems. The muon $g$-$2$ experiment at Fermilab is heavily relying on GPUs to process its data. The data acquisition system for this experiment must have the ability to create deadtime-free records from 700 $\\mu$s muon spills at a raw data rate 18 GB per second. Data will be collected using 1296 channels of $\\mu$TCA-based 800 MSPS, 12 bit waveform digitizers and processed in a layered array of networked commodity processors with 24 GPUs working in parallel to perform a fast recording of the muon decays during the spill. The...

  3. Effect of Rb on Proliferation of HepG2 Cell Line%Rb对HepG2肝癌细胞系增殖的影响

    Institute of Scientific and Technical Information of China (English)

    刘清源; 施学忠; 李来生; 孙斌

    2006-01-01

    目的 研究Rb基因及其产物对HepG2肝癌细胞系增殖的影响.方法 转染pRb质粒进入HepG2肝癌细胞系,用MTT法检测转染前后细胞增殖的变化,并将转染pRb质粒的HepG2肝癌细胞接种在裸鼠皮下建立肝癌裸鼠种植瘤模型,观察转染pRb质粒前后裸鼠体内种植瘤生长的变化.结果 转染pRb质粒的HepG2肝癌细胞与未转染pRb质粒者相比细胞增殖受到抑制.成功建立HepG2肝癌细胞裸鼠体内种植瘤模型,转染pRb质粒的HepG2肝癌细胞的裸鼠体内种植瘤生长受抑制.转染组种植瘤体积第4周(429.7±114.987)mm3,第5周(657.90±187.27)mm3,第6周(892.56±258.73)mm3.结论 Rb在体内和体外均能抑制肝癌细胞的增殖.

  4. Apoptosis and its pathway in X gene-transfected HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Na Lin; Hong-Ying Chen; Dan Li; Sheng-Jun Zhang; Zhi-Xin Cheng; Xiao-Zhong Wang

    2005-01-01

    AIM: To investigate the effect of hepatitis B virus (HBV) X gene on apoptosis and expressions of apoptosis factors in X gene-transfected HepG2 cells.METHODS: The HBV X gene eukaryon expression vector pcDNVA3-Xwas transiently transfected into HepG2 cells by lipid-media transfection. Untransfected HepG2 and HepG2 transfected with pcDNA3 were used as controls. Expression of HBx in HepG2 was identified by PT-PCR. MTT and TUNEL were employed to measure proliferation and apoptosis of cells in.three groups. Semi-quantified RT-PCR was used to evaluate the expression levels of Fas/FasL, Bax/Bcl-xL,and c-myc in each group.RESULTS: HBV X gene was transfected into HepG2 cells successfully. RT-PCR showed that HBx was only expressed in HepG2/pcDNA3-X cells, but not expressed in HepG2 and HepG2/pcDNA3 cells. Analyzed by MTT, cell proliferation capacity was obviously lower in HepG2/pcDNA3-X cells (0.08910±0.003164) than in HepG2 (0.14410±0.004927)and HepG2/pcDNA3 cells (0.12150±0.007159) (P<0.05and P<0.01). Analyzed by TUNEL, cell apoptosis was much more in HepG2/pcDNA3-X cells (980/2 000) than HepG2 (420/2 000), HepG2/pcDNA3 cells (520/2 000) (P<0.05 and P<0.01). Evaluated by semi-quantified RT-PCR, the expression level of Fas/FasL was significantly higher in HepG2 cells transfected with HBx than in HepG2 and HepG2/pcDNA3 cells (P<0.05 and P<0.01). Bax/Bcl-xL expression level was also elevated in HepG2/pcDNA3-X cells (P<0.05and P<0.01). Expression of c-myc was markedly higher in HepG2/pcDNA3-X cells than in HepG2 and HepG2/pcDNA3 cells (P<0.05 and P<0.01).CONCLUSION: HBV X gene can impair cell proliferation capacity, improve cell apoptosis, and upregulate expression of apoptosis factors. The intervention of HBV X gene on the expression of apoptosis factors may be a possible mechanism responsible for the change in cell apoptosis and proliferation.

  5. Analysis of the G2/M Checkpoint in fanconi anemia cells via examinating chromosomal instability during G2-phase and mitosis

    OpenAIRE

    Sauer, Rica

    2013-01-01

    Fanconi anemia is a genetical and phenotypical heterogenous disease, characterized through loss of one of the 15 identified genes of the Fanconi anemia pathway what causes congenital anomalies, bone marrow failure and solid tumors. In this work the G2/M checkpoint is analysed by use of the phosphatase inhibitor Calyculin A to examine the chromosomal instability, which is typical for fanconi anemia cells, not only in mitoses but also in the G2 phase of the cell cycle. It is proved that the che...

  6. 电子政务环境下的G2C模式分析%Mode Analysis of G2C on the E-government

    Institute of Scientific and Technical Information of China (English)

    邹凯; 罗卫; 何岸

    2005-01-01

    认为当前的国内外环境为我国开展电子政务打下了坚实基础,介绍政府对公民电子服务(government to citizen,G2C)模式的内涵.对G2C模式的成本效益、技术支持、战略构架和发展的制约因素进行分析,并就如何推进我国电子政务建设提出相应策略.

  7. Two zebrafish G2A homologs activate multiple intracellular signaling pathways in acidic environment

    Energy Technology Data Exchange (ETDEWEB)

    Ichijo, Yuta; Mochimaru, Yuta [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan); Azuma, Morio [Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555 (Japan); Satou, Kazuhiro; Negishi, Jun [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan); Nakakura, Takashi [Department of Anatomy, Graduate School of Medicine, Teikyo University, 2-11-1 Itabashi-Ku, Tokyo 173-8605 (Japan); Oshima, Natsuki [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan); Mogi, Chihiro; Sato, Koichi [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan); Matsuda, Kouhei [Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555 (Japan); Okajima, Fumikazu [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan); Tomura, Hideaki, E-mail: tomurah@meiji.ac.jp [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan)

    2016-01-01

    Human G2A is activated by various stimuli such as lysophosphatidylcholine (LPC), 9-hydroxyoctadecadienoic acid (9-HODE), and protons. The receptor is coupled to multiple intracellular signaling pathways, including the G{sub s}-protein/cAMP/CRE, G{sub 12/13}-protein/Rho/SRE, and G{sub q}-protein/phospholipase C/NFAT pathways. In the present study, we examined whether zebrafish G2A homologs (zG2A-a and zG2A-b) could respond to these stimuli and activate multiple intracellular signaling pathways. We also examined whether histidine residue and basic amino acid residue in the N-terminus of the homologs also play roles similar to those played by human G2A residues if the homologs sense protons. We found that the zG2A-a showed the high CRE, SRE, and NFAT activities, however, zG2A-b showed only the high SRE activity under a pH of 8.0. Extracellular acidification from pH 7.4 to 6.3 ameliorated these activities in zG2A-a-expressing cells. On the other hand, acidification ameliorated the SRE activity but not the CRE and NFAT activities in zG2A-b-expressing cells. LPC or 9-HODE did not modify any activity of either homolog. The substitution of histidine residue at the 174{sup th} position from the N-terminus of zG2A-a to asparagine residue attenuated proton-induced CRE and NFAT activities but not SRE activity. The substitution of arginine residue at the 32nd position from the N-terminus of zG2A-a to the alanine residue also attenuated its high and the proton-induced CRE and NFAT activities. On the contrary, the substitution did not attenuate SRE activity. The substitution of the arginine residue at the 10th position from the N-terminus of zG2A-b to the alanine residue also did not attenuate its high or the proton-induced SRE activity. These results indicate that zebrafish G2A homologs were activated by protons but not by LPC and 9-HODE, and the activation mechanisms of the homologs were similar to those of human G2A. - Highlights: • Zebrafish two G2A homologs are proton

  8. Low dose actinomycin treatment induces HepG2 cell cycle G2 arrest%低浓度放线菌素D诱导HepG2细胞周期G2阻滞的分子机制研究

    Institute of Scientific and Technical Information of China (English)

    肖建勇; 刘相富; 云径平

    2012-01-01

    Objective; To explore the mechanism of HepG2 cell cycle G2 arrest caused by Actinomycin D treatment. Method: HepG2 cell treated with low dose Actinomycin D for different time durations was analyzed by Flow cytometry. The translocation of Nucleophosmin (NPM) /B23 after low dose Actinomycin D treatment wasobserved by immunofluorescence. The expression changes of B23, P53 and P21 with or without Actinomycin D treatment were detected by western blotting. Result; Low dose Actinomycin D inhibited HepG2 cell growth, and caused cell cycle G2 arrest When exposed to Actinomycin D, NPM translocated from nucleolus to plasma but its expression level showed no remarkable change . Actinomycin D treatment resulted in the upregulations of P53 and P21. Conclusion; Low dose Actinomycin D treatment caused HepG2 cell cycle G2 arrest whose underlying mechanism might relate to the translocation of NPM and upregulation of P53 and P21.%目的:探讨低浓度放线菌素D处理导致HepG2细胞周期G2阻滞的分子机制.方法:应用低浓度放线菌素D处理HepG2细胞不同时间,然后应用流式细胞仪检测HepG2生长周期变化;免疫荧光观察核磷蛋白B23(NPM)定位的变化;免疫印迹法检测NPM及其细胞周期相关蛋白P53和P21表达水平.结果:低浓度放线菌素D能够抑制HepG2细胞生长并使细胞周期阻滞于G2期;在放线菌素D作用下,NPM蛋白表达水平没有明显改变,但出现定位改变,即从核仁移位到核浆;放线菌素D处理引起P53和P21蛋白表达水平上调.结论:低浓度放线菌素D作用HepG2细胞导致细胞周期G2阻滞,其机制可能与NPM移位促使其相互作用靶蛋白P53和P21蛋白水平上调有关.

  9. 16 CFR Appendix G2 to Part 305 - Furnaces-Electric

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Furnaces-Electric G2 Appendix G2 to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE CONCERNING... Part 305—Furnaces—Electric Manufacturer's rated heating capacities (Btu's/hr.) Range of annual fuel...

  10. XPD Functions as a Tumor Suppressor and Dysregulates Autophagy in Cultured HepG2 Cells.

    Science.gov (United States)

    Zheng, Jian-Feng; Li, Lin-Lin; Lu, Juan; Yan, Kun; Guo, Wu-Hua; Zhang, Ji-Xiang

    2015-05-29

    Recent clinical studies have linked polymorphisms in the xeroderma pigmentosum group D (XPD) gene, a key repair gene involved in nucleotide excision repair, to increased risk of hepatocellular carcinoma (HCC). However, the cellular effects of XPD expression in cultured HCC cells remain largely uncharacterized. Therefore, the aim of this study was to characterize the in vitro cellular effects of XPD expression on the HCC cell line HepG2. HepG2 cells were transfected as follows to create four experimental groups: pEGFP-N2/XPD plasmid (XPD) group, EGFP-N2 plasmid (N2) control group, lipofectamine™ 2000 (lipid) control group, and non-transfected (CON) control group. An MTT cell proliferation assay, Annexin V-APC apoptosis assay, colony formation assay, scratch wound migration assay, Transwell migration assay, and Western blotting of the autophagic proteins LC3 and p62 were conducted. XPD expression significantly inhibited HepG2 cell proliferation (pHepG2 cell apoptosis (pHepG2 colony formation (pHepG2 cells' migratory ability (pHepG2 cells' invasive capacity (pHepG2 cells in vitro. Further in vivo pre-clinical studies and clinical trials are needed to validate XPD's potential as a tumor-suppressive gene therapy.

  11. Tenth-order lepton g-2: Contribution of some fourth-order radiative corrections to the sixth-order g-2 containing light-by-light-scattering subdiagrams

    CERN Document Server

    Aoyama, T; Kinoshita, T; Nio, M

    2010-01-01

    This paper reports the tenth-order QED contribution to lepton g-2 from diagrams of three gauge-invariant sets VI(d), VI(g), and VI(h), which are obtained by including various fourth-order radiative corrections to the sixth-order g-2 containing light-by-light-scattering subdiagrams. In the case of electron g-2, they consist of 492, 480, and 630 vertex Feynman diagrams, respectively. The results of numerical integration, including mass-dependent terms containing muon loops, are 1.8418(95) (alpha/pi)^5 for the Set VI(d), -1.5918(65) (alpha/pi)^5 for the Set VI(g), and 0.1797(40) (alpha/pi)^5 for the Set VI(h), respectively. We also report the contributions to the muon g-2, which derive from diagrams containing an electron, muon or tau lepton loop: Their sums are -5.876(802) (alpha/pi)^5 for the Set VI(d), 5.710(490) (alpha/pi)^5 for the Set VI(g), and -8.361(232) (alpha/pi)^5 for the Set VI(h), respectively.

  12. 龙葵碱诱导HepG2细胞凋亡的观察%Study of solanine on apoptosis in HepG2 cell

    Institute of Scientific and Technical Information of China (English)

    高世勇; 邹翔; 汲晨锋; 王宏亮

    2007-01-01

    观察龙葵碱对3种消化系统肿瘤细胞株人肝癌细胞HepG2、人胃癌细胞SGC-7901、人大肠癌细胞Ls-174的细胞毒作用.并从细胞凋亡角度揭示龙葵碱对敏感细胞株的作用机制.采用MTT法观察龙葵碱对3种肿瘤细胞株的细胞毒作用;采用AO/EB双染,激光共聚焦扫描显微术(eonfocal)观察龙葵碱对HepG,肿瘤细胞形态的影响;PI单染,流式细胞仪测定龙葵碱诱导HepG2细胞凋亡的凋亡率及对细胞周期的影响.龙葵碱作用于HepG2、SGC-7901、LS-174的IC50分别为14.47μg/mL、>50μg/mL、>50μg/mL;在形态学观察实验中,阴性对照组细胞形态正常,0.003 2μg/mL、0.016μg/mL龙葵碱使细胞外周呈微弱皱缩状改变,0.08、0.4、2μg/mL龙葵碱使HepG2细胞出现大量碎片及凋亡小体等典型的细胞凋亡形态.凋亡率测定结果表明5个剂量龙葵碱诱导HepG2细胞凋亡率分别为6.0%、14.4%、17.3%、18.9%、32.2%,0.08μg/mL喜树碱诱导HepG2细胞的凋亡率为21.9%.细胞周期观察发现龙葵碱各组G2/M期均消失,S期明显升高.龙葵碱对HepG2人肝癌细胞株比较敏感,能够诱导HepG2细胞凋亡,并将HepG2细胞阻止在S期,影响肿瘤细胞DNA合成.

  13. Sensitivity of Hep G2 cells to Bacillus cereus emetic toxin.

    Science.gov (United States)

    Kamata, Yoichi; Kanno, Shinji; Mizutani, Noriko; Agata, Norio; Kawakami, Hiroshi; Sugiyama, Kei-ichi; Sugita-Konishi, Yoshiko

    2012-11-01

    We herein examined the sensitivity of Hep G2 human hepatoma cells to Bacillus cereus emetic toxin. Hep G2 cells were treated with the emetic toxin, and the cell shape was observed. The same experiments were performed for comparison purposes, using HEp-2 cells, which are currently used by most laboratories for a bioassay of the emetic toxin. Hep G2 cells showed clearer vacuolation in the cytosol within 2 hr and required a shorter incubation period than HEp-2 cells (10 hr). The number of vacuoles in the Hep G2 cells was greater, and the size of the vacuoles was larger than those observed in HEp-2 cells. The minimal concentration of the emetic toxin required to induce the vacuolation of Hep G2 cells was 0.04 ng/ml. The concentration for the HEp-2 cells was 1 ng/ml. These findings indicate that Hep G2 cells show higher sensitivity to the emetic toxin. Hep G2 cells may be superior to the currently used HEp-2 cells for the bioassay of the emetic toxin.

  14. Cells bearing chromosome aberrations lacking one telomere are selectively blocked at the G2/M checkpoint

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Pilar [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Barquinero, Joan Francesc [Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Duran, Assumpta [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Caballin, Maria Rosa [Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Ribas, Montserrat [Servei de Radiofisica i Radioproteccio de l' Hospital de la Santa Creu i Sant Pau, 08025 Barcelona (Spain); Barrios, Leonardo, E-mail: Lleonard.Barrios@uab.cat [Unitat de Biologia Cel.lular, Departament de Biologia Cel.lular, Fisiologia i Immunologia, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain)

    2009-11-02

    Cell cycle checkpoints are part of the cellular mechanisms to maintain genomic integrity. After ionizing radiation exposure, the cells can show delay or arrest in their progression through the cell cycle, as well as an activation of the DNA repair machinery in order to reduce the damage. The G2/M checkpoint prevents G2 cells entering mitosis until the DNA damage has been reduced. The present study evaluates which G0 radiation-induced chromosome aberrations are negatively selected in the G2/M checkpoint. For this purpose, peripheral blood samples were irradiated at 1 and 3 Gy of {gamma}-rays, and lymphocytes were cultured for 48 h. Calyculin-A and Colcemid were used to analyze, in the same slide, cells in G2 and M. Chromosome spreads were consecutively analyzed by solid stain, pancentromeric and pantelomeric FISH and mFISH. The results show that the frequency of incomplete chromosome elements, those lacking a telomeric signal at one end, decreases abruptly from G2 to M. This indicates that cells with incomplete chromosome elements can progress from G0 to G2, but at the G2/M checkpoint suffer a strong negative selection.

  15. Contribution of ethanol-tolerant xylanase G2 from Aspergillus oryzae on Japanese sake brewing.

    Science.gov (United States)

    Sato, Yuichiro; Fukuda, Hisashi; Zhou, Yan; Mikami, Shigeaki

    2010-12-01

    We purified three xylanase isozymes (XynF1, XynF3 and XynG2) from a solid-state Aspergillus oryzae RIB128 culture using chromatography. The results of our sake-brewing experiment, in which we used exogenously supplemented enzymes, revealed that only XynG2 improved the alcohol yield and the material utilization. The alcohol yield of the XynG2 batch displayed an increase of 4.4% in comparison to the control, and the amount of sake cake decreased by 4.6%. The contribution of XynG2 was further confirmed through our brewing experiment in which we used the yeast heterogeneously expressing fungal xylanase isozymes. Interestingly XynG1, an enzyme with a XynG2-like sequence that is more vulnerable to ethanol, did not improve the sake-mash fermentation. The stability of XynG2 in ethanol was prominent, and it retained most of its original activity after we exposed it to 80% ethanol for 30min, whereas the stability of the other isozymes in ethanol, including XynG1, was much lower (20-25% ethanol). We concluded, therefore, that the improvement of material utilization achieved with XynG2 is primarily attributable to its characteristically high stability in ethanol, thereby, effectively degrading rice endosperm cell walls under high-alcohol conditions such as a sake-mash environment.

  16. Antitumor effect of matrine in human hepatoma G2 cells by inducing apoptosis and autophagy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To study the antitumor effect of matrine in human hepatoma G2 (HepG2) cells and its molecular mechanism involved in antineoplastic activities. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect viability of HepG2 cells. The effect of matrine on cell cycle was detected by flow cytometry. Annexin-V-FITC/PI double staining assay was used to detect cellular apoptosis. Cellular morphological changes were observed under an inverted phase contrast microscope. ...

  17. g-2 of the muon from compositeness in the model of Abbott and Farhi

    Science.gov (United States)

    Brodsky, Stanley J.; Davies, Andrew J.; Volkas, Raymond R.

    1989-05-01

    We use a simple model to estimate the contribution to g-2 for the muon in the composite model of Abbott and Farhi. Dimension-5 operators must be introduced to describe the effective coupling of the composite left-handed muon to its constituents. We find an interesting suppression, which operates in the region of low scalar preon mass, of the leading-order term for g-2. The contribution of compositeness to g-2 is thus smaller than might naively be expected and is within experimental limits.

  18. Initial study on apoptosis in HepG-2 Human heptocarcinoma cell line by CSS

    Institute of Scientific and Technical Information of China (English)

    YU Lei; CUI Rong-tian; MO Ke; WANG Wei; JI Yu-bin; ZOU Xiang

    2008-01-01

    Objective To discuss on mechanism of the killing and apoptosis inducing effect induced by total alkaloid in the CSS(Capparis spinosa L. saponin, CSS)on human hepatocarcinoma cell Line HepG-2. Methods The killing effect of the CSS on human hepatocarcinoma cell Line HepG-2 was observed by MTT method. Morphological observation of the HepG-2 cells was completed by fluorescence microscope. This test was signed to observe the changes of the cell cycle of HepG-2 cells affected by the CSS by PI single-staining, and to observe if there were typical apoptosis peaks. The apoptosis inducing effect and changing of mitochondria membrane potential of the CSS on the HepG-2 cells were studied by flow cytometry. The effect of intraceUular Ca2+ level of CSS on the HepG-2 cells was measured by laser confocal microscope. Results CSS has growth inhibiting on the HepG-2 and seems to be enhanced with the increasing concentration of CSS, and its IC50 value was 46.16 μg·mL-1. The HepG-2 cells are characteristic apoptosis morphologic changed, and the apoptosis percentage is increased to 66.652 % in the 50 μg·mL-1 dosage group. The cells cycle has been changed obviously that the progresses of cells cycle of G1 period and G2 period in high dosage group have been blocked, and the cellular proportion in G2 period is decreased by the function of CSS for 24 h. The mitochondria membrane potential of HepG-2 cells induced by CSS is decreased in various degrees. In addition, the intracellular Ca2+ level is increased by the function of CSS in the middle and high dose groups. Conclusions The CSS has obviously killing and apoptosis inducing effect on human hepatoearcinoma cell Line HepG-2 by the mechanism of decreasing the mitochondria membrane potential and increasing the intracellular Ca2+ level.

  19. HepG2 cells acquire stem cell-like characteristics after immune cell stimulation.

    Science.gov (United States)

    Wang, Hang; Yang, Miqing; Lin, Ling; Ren, Hongzhen; Lin, Chaotong; Lin, Suling; Shen, Guoying; Ji, Binfeng; Meng, Chun

    2016-02-01

    The presence of cancer stem cells (CSCs) is currently regarded as one of the main culprits of tumor formation and therapy failure. It is known that chronic inflammation is associated with CSCs, but it is not clear yet how inflammation affects the development of CSCs. In the present study we aimed to examine the relationship between cancer cell stimulation mediated by immune cells and the acquisition of a CSC-like phenotype. Cancer cells derived from single hepatocarcinoma HepG2 cells were treated with mouse splenic B cells (MSBCs) and mouse peritoneal macrophage cells (MPMCs), respectively. The stem cell-like characteristics of the resulting HepG2 cells (MSBC-HepG2 and MPMC-HepG2) were evaluated using different assays, including biomarker assays, in vitro tumoroid and colony forming assays, in vivo tumor forming assays and signal transduction pathway activation assays. Various stemness characteristics of HepG2 cells, including self-renewal, proliferation, chemoresistance and tumorigenicity were evaluated. The expression levels of stemness-related genes and its encoded proteins in the MSBC-HepG2 and MPMC-HepG2 cells were assessed using RT-PCR and FACS analyses. We found that MSBC-HepG2 and MPMC-HepG2 cells possess hepatic CSC properties, including persistent self-renewal, extensive proliferation, drug resistance, high tumorigenic capacity and over-expression of CSC-related genes and proteins (i.e., EpCAM, ALDH, CD133 and CD44), compared to the parental cells. We also found that 1x10(3) MSBC-HepG2 and MPMC-HepG2 cells were able to form tumors in NOD/SCID mice and that the Notch and SHH signaling pathways were highly activated in MSBC-HepG2 cells. We conclude that the immune system may have a double-edge effect on cancer development. On one hand, immune cells such as B lymphocytes and macrophages may recognize, attack and eliminate cancer cells, whereas on the other hand, they may promote a subset of cancer cells to acquire stem cell-like characteristics.

  20. Integrated Power and Attitude Control System Demonstrated With Flywheels G2 and D1

    Science.gov (United States)

    Jansen, Ralph H.

    2005-01-01

    On September 14, 2004, NASA Glenn Research Center's Flywheel Development Team experimentally demonstrated a full-power, high-speed, two-flywheel system, simultaneously regulating a power bus and providing a commanded output torque. Operation- and power-mode transitions were demonstrated up to 2000 W in charge and 1100 W in discharge, while the output torque was simultaneously regulated between plus or minus 0.8 N-m. The G2 and D1 flywheels--magnetically levitated carbon-fiber wheels with permanent magnet motors--were used for the experiment. The units were mounted on an air bearing table in Glenn's High Energy Flywheel Facility. The operational speed range for these tests was between 20,000 and 60,000 rpm. The bus voltage was regulated at 125 V during charge and discharge, and charge-discharge and discharge-charge transitions were demonstrated by changing the amount of power that the power supply provided between 300 and 0 W. In a satellite system, this would be the equivalent of changing the amount of energy that the solar array provides to the spacecraft. In addition to regulating the bus voltage, we simultaneously controlled the net torque produced by the two flywheel modules. Both modules were mounted on an air table that was restrained by a load cell. The load cell measured the force on the table, and the torque produced by the two flywheels on the table could be calculated from that measurement. This method was used to measure the torque produced by the modules, yielding net torques from -0.8 to 0.8 N-m. This was the first Glenn demonstration of the Integrated Power and Attitude Control System (IPACS) at high power levels and speeds.

  1. Health physics during work on the G. 2 and G. 3 reactor exchanges; La radioprotection des travaux sur les echangeurs des piles G. 2 et G. 3

    Energy Technology Data Exchange (ETDEWEB)

    Rodier, J.; Chassany, J.; Guillermin, P. [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1965-07-01

    During this work and its preparation, which took place first at G. 2 and then at G. 3 over a period of 11 months, 15000 measurement results were obtained. Their analysis, together with a consideration of the organisation on the site and of the conclusions drawn from the experiment, shows the various factors which determine the importance of the radio-active dangers. (authors) [French] Au cours de ces travaux et de leur preparation, qui ont eu lieu successivement a G. 3 puis a G. 2, pendant 11 mois, 15 000 resultats de mesures ont ete obtenus. Leur etude, mise en parallele avec l'organisation du chantier et les enseignements tires de l'experience, met en evidence les divers facteurs conditionnant les niveaux de risques radioactifs. (auteurs)

  2. 双五次B-样条曲面的G2连续条件%G2 CONTINUOS CONDITIONS OF BIQUINTIC B-SPLINE SURFACES

    Institute of Scientific and Technical Information of China (English)

    赵岩; 施锡泉

    2004-01-01

    Some practical problems in designing the outline of hidden airplane require to construct high-order surfaces with at least second order continuity. The high-order smooth surfaces'construction has been always a difficuit problem in CAGD. In this paper, G2 smoothness between two biquintic surface patches is discussed, and the intrinsic conditions of the control vectors of the common boundary curve are presented.

  3. Tenth-Order QED Contribution to the Electron g-2 and an Improved Value of the Fine Structure Constant

    CERN Document Server

    Aoyama, Tatsumi; Kinoshita, Toichiro; Nio, Makiko

    2012-01-01

    This paper presents the complete QED contribution to the electron g-2 up to the tenth order. With the help of the automatic code generator, we have evaluated all 12672 diagrams of the tenth-order diagrams and obtained a_e^{(10)} = 9.16 (58) in units of (\\alpha/\\pi)^5. We have also improved the eighth-order contribution obtaining a_e^{(8)} = -1.9097 (20) in units of (\\alpha/\\pi)^4, which includes the mass-dependent contributions. These results together with the measurement of a_e lead to the improved value of the fine-structure constant \\alpha^{-1} = 137.035 999 166 (34) [0.25 ppb].

  4. [Identification of rotavirus associated to serotype G2 in Yucatan, Mexico].

    Science.gov (United States)

    Gonzales-Loza, M del R; Polanco-Marín, G G; Puerto-Solis, M

    2000-01-01

    In the present study, rotavirus G2 serotype was identified from fecal samples of children with gastroenteritis from the city of Merida, Yucatan, Mexico. Virological diagnosis of disease was performed using polycrylamide gel electrophoresis and immunoenzymatic assay. Out of 149 analyzed samples 25 (16.7%) gave positive reaction to rotavirus groups A, of these 23 (92%) were identified as serotype g2, subgroup i and electrophoretic short pattern, whereas 2 (8%) were identified as subgroups II and electrophoretic long pattern, however, the G serotype was not possible to determine. Rotavirus G serotype has not been detected in more than 90% of samples since 1985. This indicates that the number of people susceptible to G2 serotype within the population has increased over recent years, which perhaps indicates that an important outbreak of acute infectious diarrhea caused by the rotavirus G2 serotype may be forthcoming.

  5. Correlation Between Muon $g-2$ and $\\mu\\rightarrow{e}{\\gamma}$

    CERN Document Server

    Chiu, Wei-Chi; Huang, Da

    2014-01-01

    While the muon $g-2$ anomaly can be successfully explained by some new physics models, most of them are severely constrained by the $\\mu \\to e \\gamma$ bound. This tension is more transparent from the effective field theory perspective, in which the two phenomena are encoded in two very similar operators. However, with the ${\\cal O}(1)$ Wilson coefficients, the current upper bound on $\\mu \\to e \\gamma$ indicates a new-physics cutoff scale five orders smaller than that needed to eliminate the $(g-2)_\\mu$ anomaly. By summarizing all the formulae from the one-loop contributions to the muon $g-2$ with the internal-particle spin not larger than 1, we point out two general methods to reconcile the conflict between the muon $g-2$ and $\\mu \\to e \\gamma$: the GIM mechanism and the non-universal couplings. For the latter method, we use a simple scalar leptoquark model as an illustration.

  6. Gauge-covariant decomposition and magnetic monopole for G(2) Yang-Mills field

    CERN Document Server

    Matsudo, Ryutaro

    2016-01-01

    We give a gauge-covariant decomposition of the Yang-Mills field with an exceptional gauge group $G(2)$, which extends the field decomposition invented by Cho, Duan-Ge, and Faddeev-Niemi for the $SU(N)$ Yang-Mills field. As an application of the decomposition, we derive a new expression of the non-Abelian Stokes theorem for the Wilson loop operator in an arbitrary representation of $G(2)$. The resulting new form is used to define gauge-invariant magnetic monopoles in the $G(2)$ Yang-Mills theory. Moreover, we obtain the quantization condition to be satisfied by the resulting magnetic charge. The method given in this paper is general enough to be applicable to any semi-simple Lie group other than $SU(N)$ and $G(2)$.

  7. Mutation analysis of the negative regulator cyclin G2 in gastric cancer

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... Key words: Cyclin G2, gastric cancer, negative regulator, mutation screen. ... has been reported in thyroid cancer, breast cancer, oral cancer and acute ..... transformation of papillary carcinoma of the thyroid. Anticancer. Res.

  8. Parallel tractor extension and ambient metrics of holonomy split G_2

    CERN Document Server

    Graham, C Robin

    2011-01-01

    The holonomy of the ambient metrics of Nurowski's conformal structures associated to generic real-analytic 2-plane fields on 5-manifolds is investigated. It is shown that the holonomy is always contained in the split real form G_2 of the exceptional Lie group, and is equal to G_2 for an open dense set of 2-plane fields given by explicit conditions. In particular, this gives an infinite-dimensional family of metrics of holonomy equal to split G_2. These results generalize work of Leistner-Nurowski. The inclusion of the holonomy in G_2 is established by proving an ambient extension theorem for parallel tractors for conformal structures in general signature and dimension, which is expected to be of independent interest. Parallel extension beyond the critical order in even dimensions is considered in certain cases.

  9. Data of evolutionary structure change: 1AW2G-2VENA [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1AW2G-2VENA 1AW2 2VEN G A --RHPVVMGNWKLNGSKEMVVDLLNGLNAELEGVTGVDV...RQLDAVINTQGVEALEGAIIAYEPIWAIGTGKAATAEDAQRIHAQIRAHIAEK-SEAVAKNVVIQYGGSVKPENAAAYFAQPDIDGALVGGAALDAKSFAAIAKAAAE... 2VEN A 2VENA1 2VEN A 2VENA A 2VENA YEPVW-----KVATP

  10. Mitofusin 1 is degraded at G2/M phase through ubiquitylation by MARCH5

    Directory of Open Access Journals (Sweden)

    Park Yong-Yea

    2012-12-01

    Full Text Available Abstract Background Mitochondria exhibit a dynamic morphology in cells and their biogenesis and function are integrated with the nuclear cell cycle. In mitotic cells, the filamentous network structure of mitochondria takes on a fragmented form. To date, however, whether mitochondrial fusion activity is regulated in mitosis has yet to be elucidated. Findings Here, we report that mitochondria were found to be fragmented in G2 phase prior to mitotic entry. Mitofusin 1 (Mfn1, a mitochondrial fusion protein, interacted with cyclin B1, and their interactions became stronger in G2/M phase. In addition, MARCH5, a mitochondrial E3 ubiquitin ligase, reduced Mfn1 levels and the MARCH5-mediated Mfn1 ubiquitylation were enhanced in G2/M phase. Conclusions Mfn1 is degraded through the MARCH5-mediated ubiquitylation in G2/M phase and the cell cycle-dependent degradation of Mfn1 could be facilitated by interaction with cyclin B1/Cdk1 complexes.

  11. Establishment of hepatocellular carcinoma multidrug resistant monoclone cell line HepG2/mdr1

    Institute of Scientific and Technical Information of China (English)

    CHEN Yong-bing; XIE Jian-guo; YANG Jia-yin; YAN Lü-nan; YAN Mao-lin; GONG Jian-ping; XIA Ren-pin; LIU Li-xin; LI Ning; LU Shi-chun; ZHANG Jing-guang; ZENG Dao-bing

    2007-01-01

    Background The multidrug resistance (MDR) associated with the expression of the mdr1 gene and its product P-glycoprotein is a major factor in the prognosis of hepatocellular carcinoma cell (HCC) patients treated with chemotherapy. Our study was to establish a stable HCC MDR cell line where a de novo acquisition of multidrug resistance specifically related to overexpression of a transgenic mdr1.Methods The 4.5-kb mdr1 cDNA obtained from the plasmid pHaMDR1-1 was cloned into the PCI-neo mammalian expression vector, later was transferred by liposome to human hepatocarcinoma cell line HepG2. Then the transfected HepG2 cells resisting G418 were clustered and cultured and the specific fragment of mdr1 cDNA, mRNA and the P-glycoprotein (Pgp) in these HepG2 cells were detected by PCR, RT-PCR and flow cytometry, respectively. The accumulation of the daunorubicin was determinated by flow cytometry simultaneously. The nude mice model of grafting tumour was established by injecting subcutaneously HepG2/mdr1 cells in the right axilla. When the tumour diameter reached 5 mm, adriamycin was injected into peritoneal cavity. The size and growth inhibition of tumour were evaluated.Results The mdr1 expression vector was constructed successfully and the MDR HCC line HepG2/mdr1 developed.The PCR analysis showed that the specific fragment of mdr1 cDNA in HepG2/mdr1 cells, but not in the control group HepG2 cells. Furthermore, the content of the specific fragment of mdr1 mRNA and Pgp expression in HepG2/mdr1 cells were (59.7±7.9)% and (12.28±2.09)%, respectively, compared with (16.9±3.2)% and (3.07±1.06)% in HepG2 cells.In the nude mice HCC model, the tumour genes of both groups were identified. After ADM therapy, the mean size of HepG2 cell tumours was significantly smaller than HepG2/mdr1 cell tumours.Conclusion The approach using the transfer of mdr1 cDNA may be applicable to the development of MDR hepatocarcinoma cell line, whose MDR mechanism is known. This would provide the

  12. Three-dimensional structure of the human myeloma IgG2.

    Directory of Open Access Journals (Sweden)

    Sergey Ryazantsev

    Full Text Available Human immunoglobulin G, subclass 2 (hIgG2, plays an important role in immunity to bacterial pathogens and in numerous pathological conditions. However, there is a lack of information regarding the three-dimensional (3D structure of the hIgG2 molecule. We used electron microscopy (EM, differential scanning microcalorimetry (DSC and fluorescence for structural analysis of the hIgG2. DSC and fluorescence indicated two types of interaction between CH1 domain of Fab (antigen-binding fragment/subunit and CH2 domain of Fc (complement fixation fragment/subunit simultaneously present in the sample: close interaction, which increases the thermostability of both, CH1 and CH2 domains, and weak (or no interaction, which is typical for most IgGs but not hIgG2. Thermodynamics could not determine if both types of interactions are present within a single molecule. To address this question, EM was used. We employed a single-particle reconstruction and negative staining approach to reveal the three-dimensional structure of the hIgG2. A three-dimensional model of hIgG2 was created at 1.78 nm resolution. The hIgG2 is asymmetrical: one Fab subunit is in close proximity to the upper portion of the Fc subunit (CH2 domain and the other Fab is distant from Fc. The plane of Fab subunits is nearly perpendicular to Fc. EM structure of the hIgG2 is in good agreement with thermodynamic data: a Fab distant from Fc should exhibit a lower melting temperature while a Fab interacting with Fc should exhibit a higher melting temperature. Both types of Fab subunits exist within one molecule resembling an A/B hIgG2 isoform introduced earlier on physicochemical level by Dillon et al. (2008. In such an arrangement, the access to the upper portion of Fc subunit is partially blocked by a Fab subunit. That might explain for instance why hIgG2 mildly activates complement and binds poorly to Fc receptors. Understanding of the three-dimensional structure of the hIgG2 should lead to better

  13. High Permissivity of Human HepG2 Hepatoma Cells for Influenza Viruses

    OpenAIRE

    Ollier, Laurence; Caramella, Anne; Giordanengo, Valérie; Lefebvre, Jean-Claude

    2004-01-01

    Human HepG2 hepatoma cells are highly permissive for influenza virus type A and type B, even without the addition of trypsin, and they exhibit a marked cytopathic effect. This property greatly facilitates the primary isolation of influenza viruses. Virus replication was significantly reduced by the plasmin(ogen)-specific inhibitor tranexamic acid, and this suggests a potential role played by the plasminogen/tissue plasminogen activator complex at the surface of HepG2 cells. This might represe...

  14. Precision measurement of the proton and deuteron spin structure functions g2 and asymmetries A2

    Science.gov (United States)

    E155 Collaboration; Anthony, P. L.; Arnold, R. G.; Averett, T.; Band, H. R.; Benmouna, N.; Boeglin, W.; Borel, H.; Bosted, P. E.; Bültmann, S. L.; Court, G. R.; Crabb, D.; Day, D.; Decowski, P.; Depietro, P.; Egiyan, H.; Erbacher, R.; Erickson, R.; Fatemi, R.; Frlez, E.; Griffioen, K. A.; Harris, C.; Hughes, E. W.; Hyde-Wright, C.; Igo, G.; Johnson, J.; King, P.; Kramer, K.; Kuhn, S. E.; Lawrence, D.; Liang, Y.; Lindgren, R.; Lombard-Nelsen, R. M.; McKee, P.; McNulty, D. E.; Meyer, W.; Mitchell, G. S.; Mitchell, J.; Olson, M.; Penttila, S.; Peterson, G. A.; Pitthan, R.; Pocanic, D.; Prepost, R.; Prescott, C.; Raue, B. A.; Reyna, D.; Ryan, P.; Rochester, L. S.; Rock, S.; Rondon-Aramayo, O.; Sabatie, F.; Smith, T.; Sorrell, L.; Lorant, S. St.; Szalata, Z.; Terrien, Y.; Tobias, A.; Toole, T.; Trentalange, S.; Wesselmann, F. R.; Wright, T. R.; Zeier, M.; Zhu, H.; Zihlmann, B.

    2003-01-01

    We have measured the spin structure functions g2p and g2d and the virtual photon asymmetries A2p and A2d over the kinematic range /0.020. The Efremov-Leader-Teryaev integral is consistent with zero within our measured kinematic range. The absolute value of A2 is significantly smaller than the A2<√R(1+A1)/2 limit.

  15. On twistor transformations and invariant differential operator of simple Lie group G2(2)

    Science.gov (United States)

    Wang, Wei

    2013-01-01

    The twistor transformations associated to the simple Lie group G2 are described explicitly. We consider the double fibration G_2/P_2 xleftarrow {η } {G_2/B} xrArr {tau }G_2/P_1, where P1 and P2 are two parabolic subgroups of G2 and B is a Borel subgroup, and its local version: H^*_2 xleftarrow {η } F xrArr {tau } H_1, where H_1 is the Heisenberg group of dimension 5 embedded in the coset space G2/P1, F = {CP}^1 × H_1 and H^*_2 contains the nilpotent Lie group H_2 of step three. The Baker-Campbell-Hausdorff formula is used to parametrize the coset spaces, coordinates charts, their transition functions and the fibers of the projection η as complex curves. We write down the relative De-Rham sequence on F along the fibers and push it down to H_1 to get a family of matrix-valued differential operators {D}_k. Then we establish a kind of Penrose correspondence for G2: the kernel of {D}_k is isomorphic to the first cohomology of the sheaf {O} (-k ) over H^*_2. We also give the Penrose-type integral transformation u = Pf for fin {O} (-k ), which gives solutions to equations {D}_ku=0. When restricted to the real Heisenberg group, the differential operators are invariant under the action of G2(2). Exchanging P1 and P2, we derive corresponding results on H_2.

  16. Xanthorrhizol induced DNA fragmentation in HepG2 cells involving Bcl-2 family proteins

    Energy Technology Data Exchange (ETDEWEB)

    Tee, Thiam-Tsui, E-mail: thiamtsu@yahoo.com [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Cheah, Yew-Hoong [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Bioassay Unit, Herbal Medicine Research Center, Institute for Medical Research, Jalan Pahang, Kuala Lumpur (Malaysia); Meenakshii, Nallappan [Biology Department, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Mohd Sharom, Mohd Yusof; Azimahtol Hawariah, Lope Pihie [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer We isolated xanthorrhizol, a sesquiterpenoid compound from Curcuma xanthorrhiza. Black-Right-Pointing-Pointer Xanthorrhizol induced apoptosis in HepG2 cells as observed using SEM. Black-Right-Pointing-Pointer Apoptosis in xanthorrhizol-treated HepG2 cells involved Bcl-2 family proteins. Black-Right-Pointing-Pointer DNA fragmentation was observed in xanthorrhizol-treated HepG2 cells. Black-Right-Pointing-Pointer DNA fragmentation maybe due to cleavage of PARP and DFF45/ICAD proteins. -- Abstract: Xanthorrhizol is a plant-derived pharmacologically active sesquiterpenoid compound isolated from Curcuma xanthorrhiza. Previously, we have reported that xanthorrhizol inhibited the proliferation of HepG2 human hepatoma cells by inducing apoptotic cell death via caspase activation. Here, we attempt to further elucidate the mode of action of xanthorrhizol. Apoptosis in xanthorrhizol-treated HepG2 cells as observed by scanning electron microscopy was accompanied by truncation of BID; reduction of both anti-apoptotic Bcl-2 and Bcl-X{sub L} expression; cleavage of PARP and DFF45/ICAD proteins and DNA fragmentation. Taken together, these results suggest xanthorrhizol as a potent antiproliferative agent on HepG2 cells by inducing apoptosis via Bcl-2 family members. Hence we proposed that xanthorrhizol could be used as an anti-liver cancer drug for future studies.

  17. Cytostatic and genotoxic effect of temephos in human lymphocytes and HepG2 cells.

    Science.gov (United States)

    Benitez-Trinidad, A B; Herrera-Moreno, J F; Vázquez-Estrada, G; Verdín-Betancourt, F A; Sordo, M; Ostrosky-Wegman, P; Bernal-Hernández, Y Y; Medina-Díaz, I M; Barrón-Vivanco, B S; Robledo-Marenco, M L; Salazar, A M; Rojas-García, A E

    2015-06-01

    Temephos is an organophosphorus pesticide that is used in control campaigns against Aedes aegypti mosquitoes, which transmit dengue. In spite of the widespread use of temephos, few studies have examined its genotoxic potential. The aim of this study was to evaluate the cytotoxic, cytostatic and genotoxic effects of temephos in human lymphocytes and hepatoma cells (HepG2). The cytotoxicity was evaluated with simultaneous staining (FDA/EtBr). The cytostatic and genotoxic effects were evaluated using comet assays and the micronucleus technique. We found that temephos was not cytotoxic in either lymphocytes or HepG2 cells. Regarding the cytostatic effect in human lymphocytes, temephos (10 μM) caused a significant decrease in the percentage of binucleated cells and in the nuclear division index as well as an increase in the apoptotic cell frequency, which was not the case for HepG2 cells. The comet assay showed that temephos increased the DNA damage levels in human lymphocytes, but it did not increase the MN frequency. In contrast, in HepG2 cells, temephos increased the tail length, tail moment and MN frequency in HepG2 cells compared to control cells. In conclusion, temephos causes stable DNA damage in HepG2 cells but not in human lymphocytes. These findings suggest the importance of temephos biotransformation in its genotoxic effect.

  18. Anti-hepatocarcinoma effects of resveratrol nanoethosomes against human HepG2 cells

    Science.gov (United States)

    Meng, Xiang-Ping; Zhang, Zhen; Chen, Tong-sheng; Wang, Yi-fei; Wang, Zhi-ping

    2017-02-01

    Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Resveratrol (Res) has been widely investigated with its strong anti-tumor activity. However, its low oral bioavailability restricts its wide application. In this study, we prepared resveratrol nanoethosomes (ResN) via ethanol injection method. The in vitro anti-hepatocarcinoma effects of ResN relative to efficacy of bulk Res were evaluated on proliferation and apoptosis of human HepG2 cells. ResN were spherical vesicles and its particle diameter, zeta potential were (115.8 +/- 1.3) nm and (-12.8 +/- 1.9) mV, respectively. ResN exhibited significant inhibitory effects against human HepG2 cells by MTT assay, and the IC50 value was 49.2 μg/ml (105.4 μg/ml of Res bulk solution). By flow cytometry assay, there was an increase in G2/M phase cells treated with ResN. The results demonstrated ResN could effectively block the G2/M phase of HepG2 cells, which can also enhance the inhibitory effect of Res against HepG2 cells.

  19. Dovitinib induces mitotic defects and activates the G2 DNA damage checkpoint.

    Science.gov (United States)

    Man, Wing Yu; Mak, Joyce P Y; Poon, Randy Y C

    2014-01-01

    Dovitinib (TKI258; formerly CHIR-258) is an orally bioavailable inhibitor of multiple receptor tyrosine kinases. Interestingly, Dovitinib triggered a G2 /M arrest in cancer cell lines from diverse origins including HeLa, nasopharyngeal carcinoma, and hepatocellular carcinoma. Single-cell analysis revealed that Dovitinib promoted a delay in mitotic exit in a subset of cells, causing the cells to undergo mitotic slippage. Higher concentrations of Dovitinib induced a G2 arrest similar to the G2 DNA damage checkpoint. In support of this, DNA damage was triggered by Dovitinib as revealed by γ-H2AX and comet assays. The mitotic kinase CDK1 was found to be inactivated by phosphorylation in the presence of Dovitinib. Furthermore, the G2 arrest could be overcome by abrogation of the G2 DNA damage checkpoint using small molecule inhibitors of CHK1 and WEE1. Finally, Dovitinib-mediated G2 cell cycle arrest and subsequent cell death could be promoted after DNA damage repair was disrupted by inhibitors of poly(ADP-ribose) polymerases. These results are consistent with the recent finding that Dovitinib can also target topoisomerases. Collectively, these results suggest additional directions for use of Dovitinib, in particular with agents that target the DNA damage checkpoint.

  20. Suppression of E-cadherin mediates gallotannin induced apoptosis in Hep G2 hepatocelluar carcinoma cells.

    Science.gov (United States)

    Han, Hee Jeong; Kwon, Hee Young; Sohn, Eun Jung; Ko, Hyunsuk; Kim, Bogeun; Jung, Kwon; Lew, Jae Hwan; Kim, Sung-Hoon

    2014-01-01

    Though gallotannin was known to have anti-oxidant and antitumor activity, the underlying antitumor mechanism of gallotannin still remains unclear. Thus, in the present study, antitumor mechanism of gallotannin was elucidated in hepatocellular carcinoma cells. Gallotannin significantly exerted cytotoxicity against Hep G2 and Chang hepatocellular carcinoma cells with the accumulation of the sub-G1 population and increase of terminal deoxynucleotidyltransferasedUTP nick end labeling (TUNEL) positive cells as an apoptotic feature. Also, gallotannin attenuated the expression of pro-caspase9, pro-caspase3, Bcl2 and integrin β1 and cleaved poly(ADP)-ribose polymerase (PARP) in Hep G2 and Chang cancer cells. Furthermore, gallotannin suppressed cell repair motility by wound healing assay and also inhibited cell adhesion in Hep G2 cells. Of note, gallotannin attenuated the expression of epithelial cadherin (E-cadherin) to form cell-cell adhesion from the early stage, and also beta-catenin at late phase in Hep G2 cells. Consistently, Immunofluorescence assay showed that E-cadherin or β-catenin expression was suppressed in a time dependent manner by gallotannin. Furthermore, silencing of E-cadherin by siRNA transfection method enhanced PAPR cleavage, caspase 3 activation and sub G1 population and attenuated the cell adhesion induced by gallotannin in Hep G2 cells. Overall, our findings demonstrate that the disruption of cell adhesion junction by suppression of E-cadherin mediates gallotannin enhanced apoptosis in Hep G2 liver cancer cells.

  1. Antitumor effects of polysaccharide from Sargassum fusiforme against human hepatocellular carcinoma HepG2 cells.

    Science.gov (United States)

    Fan, Sairong; Zhang, Junfeng; Nie, Wenjian; Zhou, Wenyuan; Jin, Liqin; Chen, Xiaoming; Lu, Jianxin

    2017-04-01

    Sargassum fusiforme (Harv.) Setchel, a kind of brown algae, has been applied as a therapeutic for thousands of years. This study was designed to investigate the antitumor effects of the polysaccharide (SFPS) from S. fusiform in liver cancer. The mice inoculated with HepG2 cells were orally administrated with SFPS at the doses of 100, 200 and 400 mg/kg body weight for 28 days. The products from peritoneal macrophages and serum in HepG2-bearing mice were measured. The effect of SFPS-induced cell apoptosis was measured by flow cytometry. Meanwhile, the expression levels of Bax and Bcl-2 were detected. Furthermore, the cytotoxicity of SFPS was evaluated by CCK-8 assay. Results showed that SFPS significantly inhibited growth of human HepG2 cell-transplanted tumor in nude mice, and remarkably increased serum TNF-α, IL-1, NO and IgM levels in HepG2-bearing mice. SFPS also promoted the cytokines (IL-1 and TNF-α) secreted by peritoneal macrophages in HepG2-bearing mice. SFPS exerted a stimulatory effect on apoptosis of HepG2 cells, increased the expression of Bax, and decreased the expression of Bcl-2. The results indicated that SFPS has anti-tumor and immunomodulatory activities at the high concentration, and it could be used as a potential chemopreventative and/or adjuvant chemotherapeutic agent in liver cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Cyclin G2 Promotes Hypoxia- Driven Local Invasion of Glioblastoma by Orchestrating Cytoskeletal Dynamics

    Directory of Open Access Journals (Sweden)

    Atsushi Fujimura

    2013-11-01

    Full Text Available Microenvironmental conditions such as hypoxia potentiate the local invasion of malignant tumors including glioblastomas by modulating signal transduction and protein modification, yet the mechanism by which hypoxia controls cytoskeletal dynamics to promote the local invasion is not well defined. Here, we show that cyclin G2 plays pivotal roles in the cytoskeletal dynamics in hypoxia-driven invasion by glioblastoma cells. Cyclin G2 is a hypoxia-induced and cytoskeleton-associated protein and is required for glioblastoma expansion. Mechanistically, cyclin G2 recruits cortactin to the juxtamembrane through its SH3 domain-binding motif and consequently promotes the restricted tyrosine phosphorylation of cortactin in concert with src. Moreover, cyclin G2 interacts with filamentous actin to facilitate the formation of membrane ruffles. In primary glioblastoma, cyclin G2 is abundantly expressed in severely hypoxic regions such as pseudopalisades, which consist of actively migrating glioma cells. Furthermore, we show the effectiveness of dasatinib against hypoxia-driven, cyclin G2-involved invasion in vitro and in vivo. Our findings elucidate the mechanism of cytoskeletal regulation by which severe hypoxia promotes the local invasion and may provide a therapeutic target in glioblastoma.

  3. IgG2 Fc structure and the dynamic features of the IgG CH2-CH3 interface.

    Science.gov (United States)

    Teplyakov, Alexey; Zhao, Yonghong; Malia, Thomas J; Obmolova, Galina; Gilliland, Gary L

    2013-11-01

    The analyses of two human IgG2 Fc structures, determined in different crystal forms, and the comparison with IgG1 Fc structures reveals molecular features that are involved in accommodating and stabilizing structural conformations. In the IgG2 Fc structures relative positions of the CH2 domains with respect to the CH3 domains vary significantly from those observed for IgG1 Fc structures in similar unit cells. The analysis reveals that the movement of the CH2 domain in all of the Fc structures results from a pivoting around a highly conserved ball-and-socket-like joint in which the CH2 L251 side chain (the ball) interacts with a pocket (the socket) formed by CH3 M428, H429, E430, and H435. Despite the change in positioning of the CH2 and CH3 domains, conserved hydrogen bonds and electrostatic interactions are retained, stabilizing the Fc domain interface. In the high resolution IgG2 and IgG1 Fc structures the position and number of water molecules, and water networks bridging the two domains differ significantly because of the difference in positions of CH2 relative to CH3. At the domain interface, only CH2 T339 in IgG2 differs from alanine found in IgG1 and IgG4. This residue's side chain influences the water structure at the interface by interacting either directly or through a bridging water molecule with D376 in the CH3 BC loop. Thus, the analyses of the IgG2 Fc structures and their comparisons with IgG1 Fc structures reveals similar, but distinctly different dynamic CH2-CH3 interfaces that can accommodate a wide range of CH2-CH3 conformations, that in conjunction with the amino acid residues in the hinge region, may influence FcγR effector function profiles. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Cyclin G2 suppresses estrogen-mediated osteogenesis through inhibition of Wnt/β-catenin signaling.

    Directory of Open Access Journals (Sweden)

    Jinlan Gao

    Full Text Available Estrogen plays an important role in the maintenance of bone formation, and deficiency in the production of estrogen is directly linked to postmenopausal osteoporosis. To date, the underlying mechanisms of estrogen-mediated osteogenic differentiation are not well understood. In this study, a pluripotent mesenchymal precursor cell line C2C12 was used to induce osteogenic differentiation and subjected to detection of gene expressions or to manipulation of cyclin G2 expressions. C57BL/6 mice were used to generate bilateral ovariectomized and sham-operated mice for analysis of bone mineral density and protein expression. We identified cyclin G2, an unconventional member of cyclin, is involved in osteoblast differentiation regulated by estrogen in vivo and in vitro. In addition, the data showed that ectopic expression of cyclin G2 suppressed expression of osteoblast transcription factor Runx2 and osteogenic differentiation marker genes, as well as ALP activity and in vitro extracellular matrix mineralization. Mechanistically, Wnt/β-catenin signaling pathway is essential for cyclin G2 to inhibit osteogenic differentiation. To the best of our knowledge, the current study presents the first evidence that cyclin G2 serves as a negative regulator of both osteogenesis and Wnt/β-catenin signaling. Most importantly, the basal and 17β-estradiol-induced osteogenic differentiation was restored by overexpression of cyclin G2. These results taken together suggest that cyclin G2 may function as an endogenous suppressor of estrogen-induced osteogenic differentiation through inhibition of Wnt/β-catenin signaling.

  5. Overexpression of Bmi‑1 promotes epithelial‑mesenchymal transition in CD133+Hep G2 cells.

    Science.gov (United States)

    Zhang, Zefeng; Wang, Qiyi; Bu, Xiaoling; Zhang, Chuangqiang; Chen, Hao; Sha, Weihong; Liu, Wanwei

    2017-08-24

    Cancer stem cells (CSCs) and epithelial‑mesenchymal transition (EMT) are critical factors contributing to tumor metastasis and recurrence. The BMI1 proto‑oncogene (Bmi‑1) promotes the development and progression of hematologic malignancies and of several types of solid tumors. The aim of the present study was to explore the mechanism by which Bmi‑1 may promote invasion and migration of hepatocellular carcinoma Hep G2 cells. CD133 antigen is a transmembrane glycoprotein and regarded as a cancer stem cells marker in hepatocellular carcinoma. CD133+Hep G2 cells were enriched by magnetic‑activated cell sorting and exhibited greater viability compared with CD133‑Hep G2 cells, as measured by Cell Counting kit‑8 assay. Then, Bmi‑1 was overexpressed in CD133+Hep G2 cells by transfection with the Bmi‑1/pcDNA3.1(+) expression plasmid, and overexpression was confirmed by reverse‑transcription‑polymerase chain reaction and western blotting. Overexpression of Bmi‑1in CD133+Hep G2 cells resulted in the downregulation of E‑cadherin and upregulation of Vimentin at the protein level. The invasion and migration abilities of CD133+Hep G2 cells were increased in the Bmi‑1/pcDNA3.1(+)‑transfected group, as measured by Transwell invasion and wound healing assays, respectively. In conclusion, Bmi‑1 promoted invasion and migration of CD133+Hep G2 cells most likely through inducing EMT. The present findings may offer a potential novel target for the development of hepatocellular carcinoma therapies.

  6. Inhibition of aldose reductase ameliorates ethanol‑induced steatosis in HepG2 cells.

    Science.gov (United States)

    Qiu, Longxin; Cai, Chengchao; Zhao, Xiangqian; Fang, Yan; Tang, Weibiao; Guo, Chang

    2017-05-01

    Aldose reductase (AR) expression is increased in liver tissue of patients with ethanol‑induced liver disease. However, the exact role of AR in the development of ethanol‑induced liver disease has yet to be elucidated. The present study aimed to determine the effect of an AR inhibitor on ethanol‑induced steatosis in HepG2 cells and to identify possible underlying molecular mechanisms. Steatosis was induced in HepG2 cells by stimulating cells with 100 mM absolute ethanol for 48 h. Oil Red O staining was used to detect the lipid droplet accumulation in cells. Western blot analyses were used to determine protein expression levels and reverse transcription‑quantitative polymerase chain reaction was used to analyze mRNA expression levels. The results showed that AR protein expression was elevated in HepG2 cells stimulated with ethanol. HepG2 cells exhibited marked improvement of ethanol‑induced lipid accumulation following treatment with the AR inhibitor zopolrestat. Phosphorylation levels of 5' adenosine monophosphate‑activated protein kinase (AMPK) were markedly higher, whereas the mRNA expression levels of sterol‑regulatory element‑binding protein (SREBP)‑1c and fatty acid synthase (FAS) were significantly lower in zopolrestat‑treated and ethanol‑stimulated HepG2 cells compared with in untreated ethanol‑stimulated HepG2 cells. In addition, zopolrestat inhibited the ethanol‑induced expression of tumor necrosis factor (TNF)‑α. These results suggested that zopolrestat attenuated ethanol‑induced steatosis by activating AMPK and subsequently inhibiting the expression of SREBP‑1c and FAS, and by suppressing the expression of TNF‑α in HepG2 cells.

  7. Developmental Stage-Specific Embryonic Induction of HepG2 Cell Differentiation.

    Science.gov (United States)

    Li, Yanning; Zong, Yanhong; Xiao, Zhigang; Zhu, Mengxuan; Xiao, Hui; Qi, Jinsheng; Liu, Kun; Wang, Hui

    2016-04-01

    Although hepatocellular carcinoma cells can sometimes undergo differentiation in an embryonic microenvironment, the mechanism is poorly understood. The developmental stage-specific embryonic induction of tumor cell differentiation was investigated. Both chick and mouse liver extracts and hepatoblast-enriched cells at different developmental stages were used to treat human hepatoma HepG2 cells, and the effects on the induction of differentiation were evaluated. The nuclear factors controlling differentiation, hepatocyte nuclear factor (HNF)-4α, HNF-1α, HNF-6 and upstream stimulatory factor-1 (USF-1), and the oncogene Myc and alpha-fetoprotein (AFP) were measured. HNF-4α RNA interference was used to verify the role of HNF-4α. Embryonic induction effects were further tested in vivo by injecting HepG2 tumor cells into immunodeficient nude mice. The 9-11-days chick liver extracts and 13.5-14.5-days mouse hepatoblast-enriched cells could inhibit proliferation and induce differentiation of HepG2 cells, leading to either death or maturation to hepatocytes. The maturation of surviving HepG2 cells was confirmed by increases in the expressions of HNF-4α, HNF-1α, HNF-6, and USF-1, and decreases in Myc and AFP. The embryonic induction of HepG2 cell maturation could be attenuated by HNF-4α RNA interference. Furthermore, the 13.5-days mouse hepatoblast culture completely eliminated HepG2 tumors with inhibited Myc and induced HNF-4α, confirming this embryonic induction effect in vivo. This study demonstrated that developmental stage-specific embryonic induction of HepG2 cell differentiation might help in understanding embryonic differentiation and oncogenesis.

  8. Altered cellular metabolism of HepG2 cells caused by microcystin-LR.

    Science.gov (United States)

    Ma, Junguo; Feng, Yiyi; Jiang, Siyu; Li, Xiaoyu

    2017-06-01

    This study aimed to evaluate the possible effects of microcystin-LR (MC-LR) exposure on the metabolism and drug resistance of human hepatocellular carcinoma (HepG2) cells. For this purpose, we first conducted an experiment to make sure that MC-LR could penetrate the HepG2 cell membrane effectively. The transcriptional levels of phase I (such as CYP2E1, CYP3A4, and CYP26B1) and phase II (such as EPHX1, SULTs, and GSTM) enzymes and export pump genes (such as MRP1 and MDR1) were altered by MC-LR-exposure for 24 h, indicating that MC-LR treatment may destabilize the metabolism of HepG2 cells. Further research showed that the CYP inducers omeprazole, ethanol, and rifampicin inhibited cell viability, in particular, ethanol, a CYP2E1 inducer, induced ROS generation, lipid peroxidation, and apoptosis in HepG2 cells treated with MC-LR. The CYP2E1 inhibitor chlormethiazole inhibited ROS generation, mitochondrial membrane potential loss, caspase-3 activity, and cytotoxicity caused by MC-LR. Meanwhile, the results also showed that co-incubation with the ROS scavenger l-ascorbic acid and MC-LR decreased ROS levels and effectively prevented apoptosis. These findings provide an interesting mechanistic explanation of cellular metabolism associated with MC-LR, i.e., MC-LR-exposure exerted toxicity on HepG2 cells and induced apoptosis of HepG2 cells via promoting CYP2E1 expression and inducing excessive ROS in HepG2 cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Ammonia metabolism capacity of HepG2 cells with high expression of human glutamine synthetase

    Institute of Scientific and Technical Information of China (English)

    Nan-Hong Tang; Xiao-Qian Wang; Xiu-Jin Li; Yan-Ling Chen

    2008-01-01

    BACKGROUND:Currently, one of the tough problems for the application of bioartiifcial liver (BAL) is the shortage of suitable hepatocytes. There are reports on different types of BAL assistance developed with porcine hepatocytes and HepG2 C3A cells, but their defects are obvious. In recent years, some studies focus more on liver cells with features of human origin and improved detoxiifcation. In this study, a hepatocyte line with high expression of human glutamine synthetase (hGS) was raised and its capacity for ammonia metabolism was investigated. METHODS:hGS cDNA and alpha-fetoprotein transcription regulatory element (AFP-TRE) were cloned with the designed primers. The eukaryotic expression vectors, pLNChGS and pLNAFhGS, were constructed and transfected into PA317 cells. Recombinant retroviruses (Retro-hGS and Retro-AFhGS) were produced and then infected into HepG2 cells. G418-resistant cell clones, HepG2/pLNChGS and HepG2/pLNAFhGS, were selected and ampliifed. Then hGS mRNA was measured by semi-quantitative RT-PCR;hGS enzymatic activity and ammonia metabolism analysis in different concentration of NH4+were detected with a quantitative biochemistry kit. The cell proliferation was also detected by MTT chromatometry. RESULTS:The expression of hGS mRNA in HepG2/pLNChGS cells (8.306±0.336) and HepG2/pLNAFhGS cells (21.358±1.716) was much stronger than in control cells (P CONCLUSION:The constructed hepatocytes (HepG2 cells) with speciifc high-expression of hGS have a powerful ability to degrade ammonia in vitro, and provide necessary experimental data for the selection of biomaterials in BAL.

  10. Selective Cytotoxicity of Goniothalamin against Hepatoblastoma HepG2 Cells

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    Noorjahan B. Alitheen

    2011-04-01

    Full Text Available Liver cancer has become one of the major types of cancer with high mortality and liver cancer is not responsive to the current cytotoxic agents used in chemotherapy. The purpose of this study was to examine the in vitro cytotoxicity of goniothalamin on human hepatoblastoma HepG2 cells and normal liver Chang cells. The cytotoxicity of goniothalamin against HepG2 and liver Chang cell was tested using MTT cell viability assay, LDH leakage assay, cell cycle flow cytometry PI analysis, BrdU proliferation ELISA assay and trypan blue dye exclusion assay. Goniothalamin selectively inhibited HepG2 cells [IC50 = 4.6 (±0.23 µM in the MTT assay; IC50 = 5.20 (±0.01 µM for LDH assay at 72 hours], with less sensitivity in Chang cells [IC50 = 35.0 (±0.09 µM for MTT assay; IC50 = 32.5 (±0.04 µM for LDH assay at 72 hours]. In the trypan blue dye exclusion assay, the Viability Indexes were 52 ± 1.73% for HepG2 cells and 62 ± 4.36% for Chang cells at IC50 after 72 hours. Cytotoxicity of goniothalamin was related to inhibition of DNA synthesis, as revealed by the reduction of BrdU incorporation. At 72 hours, the lowest concentration of goniothalamin (2.3 µL retained 97.6% of normal liver Chang cells proliferation while it reduced HepG2 cell proliferation to 19.8% as compared to control. Besides, goniothalamin caused accumulation of hypodiploid apoptosis and different degree of G2/M arrested as shown in cell cycle analysis by flow cytometry. Goniothalamin selectively killed liver cancer cell through suppression of proliferation and induction of apoptosis. These results suggest that goniothalamin shows potential cytotoxicity against hepatoblastoma HepG2 cells.

  11. Pro-apoptotic effects of tectorigenin on human hepatocellular carcinoma HepG2 cells

    Science.gov (United States)

    Jiang, Chun-Ping; Ding, Hui; Shi, Da-Hua; Wang, Yu-Rong; Li, Er-Guang; Wu, Jun-Hua

    2012-01-01

    AIM: To investigate the effects of tectorigenin on human hepatocellular carcinoma (HCC) HepG2 cells. METHODS: Tectorigenin, one of the main components of rhizome of Iris tectorum, was prepared by simple methods, such as extraction, filtration, concentration, precipitation and recrystallization. HepG2 cells were incubated with tectorigenin at different concentrations, and their viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptosis was detected by morphological observation of nuclear change, agarose gel electrophoresis of DNA ladder, and flow cytometry with Hoechst 33342, Annexin V-EGFP and propidium iodide staining. Generation of reactive oxygen species was quantified using DCFH-DA. Intracellular Ca2+ was monitored by Fura 2-AM. Mitochondrial membrane potential was monitored using Rhodamine 123. Release of cytochrome c from mitochondria to cytosol was detected by Western blotting. Activities of caspase-3, -8 and -9 were investigated by Caspase Activity Assay Kit. RESULTS: The viability of HepG2 cells treated by tectorigenin decreased in a concentration- and time-dependent manner. The concentration that reduced the number of viable HepG2 cells by 50% (IC50) after 12, 24 and 48 h of incubation was 35.72 mg/L, 21.19 mg/L and 11.06 mg/L, respectively. However, treatment with tectorigenin at 20 mg/L resulted in a very slight cytotoxicity to L02 cells after incubation for 12, 24 or 48 h. Tectorigenin at a concentration of 20 mg/L greatly inhibited the viability of HepG2 cells and induced the condensation of chromatin and fragmentation of nuclei. Tectorigenin induced apoptosis of HepG2 cells in a time- and dose-dependent manner. Compared with the viability rate, induction of apoptosis was the main mechanism of the anti-proliferation effect of tectorigenin in HepG2 cells. Furthermore, tectorigenin-induced apoptosis of HepG2 cells was associated with the generation of reactive oxygen species, increased intracellular [Ca2+]i

  12. Centrosome-associated regulators of the G2/M checkpoint as targets for cancer therapy

    Directory of Open Access Journals (Sweden)

    Broaddus Russell R

    2009-02-01

    Full Text Available Abstract In eukaryotic cells, control mechanisms have developed that restrain cell-cycle transitions in response to stress. These regulatory pathways are termed cell-cycle checkpoints. The G2/M checkpoint prevents cells from entering mitosis when DNA is damaged in order to afford these cells an opportunity to repair the damaged DNA before propagating genetic defects to the daughter cells. If the damage is irreparable, checkpoint signaling might activate pathways that lead to apoptosis. Since alteration of cell-cycle control is a hallmark of tumorigenesis, cell-cycle regulators represent potential targets for therapy. The centrosome has recently come into focus as a critical cellular organelle that integrates G2/M checkpoint control and repairs signals in response to DNA damage. A growing number of G2/M checkpoint regulators have been found in the centrosome, suggesting that centrosome has an important role in G2/M checkpoint function. In this review, we discuss centrosome-associated regulators of the G2/M checkpoint, the dysregulation of this checkpoint in cancer, and potential candidate targets for cancer therapy.

  13. Muon Beam Tracking and Spin-Orbit Correlations for Precision g-2 Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Tarazona, David [Michigan State U., East Lansing (main); Berz, Martin [Michigan State U., East Lansing (main); Hipple, Robert [Michigan State U., East Lansing (main); Makino, Kyoko [Michigan State U., East Lansing (main); Syphers, Michael [Fermilab

    2016-06-01

    The main goal of the Muon g-2 Experiment (g-2) at Fermilab is to measure the muon anomalous magnetic moment to unprecedented precision. This new measurement will allow to test the completeness of the Standard Model (SM) and to validate other theoretical models beyond the SM. The close interplay of the understanding of particle beam dynamics and the preparation of the beam properties with the experimental measurement is tantamount to the reduction of systematic errors in the determination of the muon anomalous magnetic moment. We describe progress in developing detailed calculations and modeling of the muon beam delivery system in order to obtain a better understanding of spin-orbit correlations, nonlinearities, and more realistic aspects that contribute to the systematic errors of the g-2 measurement. Our simulation is meant to provide statistical studies of error effects and quick analyses of running conditions for when g-2 is taking beam, among others. We are using COSY, a differential algebra solver developed at Michigan State University that will also serve as an alternative to compare results obtained by other simulation teams of the g-2 Collaboration.

  14. G2's closest approach to the Galactic Center black hole

    Science.gov (United States)

    Witzel, Gunther; Ghez, Andrea M.; Morris, Mark; Sitarski, Breann; Boehle, Anna; Campbell, Randall

    2015-01-01

    We report new observations of Galactic Center sources G2 and Sgr A* from the W. M. Keck Observatory. Both sources are of great interest and vary temporally; G2 is the putative gas cloud now passing through periapse in its orbit around the black hole at the center of the Milky Way Galaxy and Sgr A* is the emission associated with the central black hole. Our observations were obtained on 2014 March 19 & 20 (UT) with the Keck II laser guide star adaptive optics system (LGSAO) and the facility near-infrared camera (NIRC2) through the K' and L' broadband filters. At this time, G2 was expected to have been at closest approach with a separation from Sgr A* of only ~20 mas and, therefore, to be spatially unresolved from Sgr A*. Nevertheless, the two can be disentangled spectrally. In the L'-band, both Sgr A* and G2 contribute to the total flux; however, Sgr A*'s L' flux is estimated and removed based on (1) the analysis of K'-band maps showing bright and low states of Sgr A* (2) the well measured and constant K'-L' color of Sgr A*. We conclude that G2, which is currently experiencing its closest approach, is still intact and compact, in contrast to predictions for a simple gas cloud hypothesis and therefore most likely hosts a central star.

  15. Midkine accumulated in nucleolus of HepG2 cells involved in rRNA transcription

    Institute of Scientific and Technical Information of China (English)

    Li-Cheng Dai; Jian-Zhong Shao; Li-Shan Min; Yong-Tao Xiao; Li-Xin Xiang; Zhi-Hong Ma

    2008-01-01

    AIM: To invesgate the ultrastructural location of midkine (MK) in nucleolus and function corresponding to its location. METHODS: To investigate the ultrastructural location of MK in nucleolus with immunoelectronic microscopy. To study the role that MK plays in ribosomal biogenesis by real-time PCR. The effect of MK on anti-apoptotic activity of HepG2 cells was studied with FITC-conjugated annexin V and propidium iodide PI double staining through FACS assay. RESULTS: MK mainly localized in the granular component (GC), dense fibrillar component (DFC) and the border between the DF-C and fibrillar center (FC). The production of 45S precursor rRNA level was decreased significantly in the presence of IK antisense oligonucleotide in the HepG2 cells. Furthermore, it was found that exogenous MK could protect HepG2 from apoptosis significantly. CONCLUSION: NK was constitutively translocated to the nucleolus of HepG2 cells, where it accumulated and mostly distributed at DFC, GC components and at the region between FC and DFC, MK played an important role in rRNA transcription, ribosome biogenesis, and cell proliferation in HepG2 cells. MK might serve as a molecular target for therapeutic intervention of human carcinomas.

  16. Effects of sargentgloryvine stem extracts on HepG-2 cells in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    Ming-Hua Wang; Min Long; Bao-Yi Zhu; Shu-Hui Yang; Ji-Hong Ren; Hui-Zhong Zhang

    2011-01-01

    AIM: To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro and in vivo and determine its mechanisms of action.METHODS: Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric, TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining. Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS: SSE treatment could not only inhibit HepG-2 cell proliferation in a dose- and time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase. The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P 0.05). Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION: SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.

  17. Buckwheat trypsin inhibitor enters Hep G2 cells by clathrin-dependent endocytosis.

    Science.gov (United States)

    Cui, Xiaodong; Wang, Zhuanhua; Li, Yuying; Li, Chen

    2013-12-01

    Recombinant buckwheat trypsin inhibitor (rBTI) was studied to evaluate if it could enter cancer cells and to determine the mechanism. Fluorescein isothiocyanate-labelled buckwheat trypsin inhibitor (FITC-BTI) entered Hep G2 cells in a concentration-dependent manner. FITC-BTI colocalised with labelled transferrin (Tf) in the punctate structure, implying that rBTI enters Hep G2 cells by clathrin-dependent endocytosis. Incubation of Hep G2 cells with different chemical inhibitors abolished diffuse, but not punctate fluorescence, thus indicating that membrane potential plays a critical role in this process. Impairment of clathrin-mediated endocytosis by RNAi with clathrin heavy chain greatly reduced or completely abolished both diffuse and punctate fluorescence, further supporting a theory of a single route of endocytosis. Consistent with our working hypothesis, Hep G2 cells which were arrested in the M phase did not show any vesicular or diffuse FITC-BTI. We conclude from these results that both endocytosis and membrane potential are required for rBTI entry into Hep G2 cells. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. G2 - G3 inventive properties, the first french nuclear plants; Caracteristiques generales et aspects originaux des reacteurs G2 et G3

    Energy Technology Data Exchange (ETDEWEB)

    Pascal; Horowitz; Bussac; Joatton; De Lagge de Meux; Martin [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    This paper points out the inventive properties of the frenchctors G2 and G3. These are dual purpose reactors, i.e. designed for the production of both plutonium and energy (30 electrical MW); in this respect, they can be considered as the start point of the french electrical energy produced from nuclear fuel. The following points are specially discussed in this paper: the choice of the prestressed concrete pressure vessel, the horizontal arrangement of the channels, the interest of neutron flux flattening, the advantages of the charging and discharging device working during pile operation. (author)Fren. [French] Les caracteres originaux des reacteurs fran is G2 et G3 sont decrits dans ce rapport. Ce sont des reacteurs a double fin, plutonigenes et aussi producteurs d'energie (30 MW electriques); ils constituent a ce titre le point de depart de la production fran ise d'electricite d'origine nucleaire. Sont discutes, en particulier, dans ce rapport: le choix du caisson en beton precontraint pour tenir la pression, la disposition horizontale des canaux, l'interet de l'aplatissement du flux neutronique, les avantages de l'appareil permettant le chargement et le dechargement du combustible sans arreter la pile. (auteur)

  19. Targeting and molecular imaging of HepG2 cells using surface-functionalized gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Rathinaraj, Pierson [Auckland University of Technology, Institute of Biomedical Technologies (New Zealand); Lee, Kyubae; Choi, Yuri; Park, Soo-Young [Kyungpook National University, School of Applied Chemical Engineering, Graduate School (Korea, Republic of); Kwon, Oh Hyeong [Kumoh National Institute of Technology, Department of Polymer Science and Engineering (Korea, Republic of); Kang, Inn-Kyu, E-mail: ikkang@knu.ac.kr [Kyungpook National University, School of Applied Chemical Engineering, Graduate School (Korea, Republic of)

    2015-07-15

    Mercaptosuccinic acid (M)-conjugated gold nanoparticles (GM) were prepared and characterized by transmission electron microscope and dynamic light scattering. M was used to improve the monodispersity and non-specific intracellular uptake of nanoparticles. Lactobionic acid (L) was subsequently conjugated to the GM to target preferentially HepG2 cells (liver cancer cells) that express asialoglycoprotein receptors (ASGPR) on their membrane surfaces and facilitate the transit of nanoparticles across the cell membrane. The mean size of lactobionic acid-conjugated gold nanoparticle (GL) was approximately 10 ± 0.2 nm. Finally, the Atto 680 dye (A6) was coupled to the nanoparticles to visualize their internalization into HepG2 cells. The interaction of surface-modified gold nanoparticles with HepG2 cells was studied after culturing cells in media containing the GM or L-conjugated GM (GL)

  20. SEM-668-G2(日东科技)

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    SEM-668-G2比SEM-668在视觉技术上更加精湛,采用美国AGILENT(安提伦)LASER 5519A及HP的双重频率技术,加强运动;隹确性。在智能化印刷头上,SEM-668-G2印刷质量更加均匀、稳定,操作界面更加简易、更加人性化。在综合性能上更加卓越,保证实现现代化的生产效率。产品体具性能如下:SEM-668-G2视觉全自动印刷机

  1. Applying inversion to construct planar, rational spirals that satisfy two-point G(2) Hermite data

    CERN Document Server

    Kurnosenko, A

    2010-01-01

    A method of two-point G(2) Hermite interpolation with spirals is proposed. To construct a sought for curve, the inversion is applied to an arc of some other spiral. To illustrate the method, inversions of parabola are considered in detail. The resulting curve is 4th degree rational. The method allows the matching of a wide range of boundary conditions, including those which require an inflection. Although not all G(2) Hermite data can be matched with a spiral generated from a parabolic arc, introducing one intermediate G(2) data solves the problem. Expanding the method by involving other spirals arcs is also discussed. (C) 2009 Elsevier B.V. All rights reserved.

  2. Anticancer and apoptosis-inducing effects of Moringa concanensis using hepG2 cell lines

    Directory of Open Access Journals (Sweden)

    V. Balamurugan

    2014-12-01

    Full Text Available The objective of the present investigation is focused on the anticancer activity of the ethanolic crude extract of Moringa concanensis leaf and bark against HepG2 cell line. The study was facilitated by collecting the plant sample and subjected to ethanol crude extraction. The anticancer activity of the crude extracted sample against HepG2 cell line was examined by MTT assay. The study confirms that the leaf crude extract of M. concanensis has pronounced anticancer potential against HepG2 cell lines while compared to that of the bark extract. The plant investigated possesses remarkable anticancer activity and hence isolation of the compound contributing to the activity may lead to develop at a novel and natural phytomedicine for the disease.

  3. Observations of the gas cloud G2 in the Galactic Center

    CERN Document Server

    Gillessen, Stefan; Fritz, Tobias K; Eisenhauer, Frank; Pfuhl, Oliver; Ott, Thomas; Burkert, Andreas; Schartmann, Marc; Ballone, Alessandro

    2013-01-01

    In 2011, we discovered a compact gas cloud ("G2") with roughly three Earth masses that is falling on a near-radial orbit toward the massive black hole in the Galactic Center. The orbit is well constrained and pericenter passage is predicted for early 2014. Our data beautifully show that G2 gets tidally sheared apart due to the massive black hole's force. During the next months, we expect that in addition to the tidal effects, hydrodynamics get important, when G2 collides with the hot ambient gas around Sgr A*. Simulations show that ultimately, the cloud's material might fall into the massive black hole. Predictions for the accretion rate and luminosity evolution, however, are very difficult due to the many unknowns. Nevertheless, this might be a unique opportunity in the next years to observe how gas feeds a massive black hole in a galactic nucleus.

  4. Observations of the gas cloud G2 in the Galactic center

    Science.gov (United States)

    Gillessen, S.; Genzel, R.; Fritz, T. K.; Eisenhauer, F.; Pfuhl, O.; Ott, T.; Burkert, A.; Schartmann, M.; Ballone, A.

    2014-05-01

    In 2011, we discovered a compact gas cloud ("G2") with roughly three Earth masses that is falling on a near-radial orbit toward the massive black hole in the Galactic center. The orbit is well constrained and pericenter passage is predicted for early 2014. Our data beautifully show that G2 gets tidally sheared apart due to the massive black hole's force. During the next months, we expect that in addition to the tidal effects, hydrodynamics get important, when G2 collides with the hot ambient gas around Sgr A*. Simulations show that ultimately, the cloud's material might fall into the massive black hole. Predictions for the accretion rate and luminosity evolution, however, are very difficult due to the many unknowns. Nevertheless, this might be a unique opportunity in the next years to observe how gas feeds a massive black hole in a galactic nucleus.

  5. Replicatively senescent cells are arrested in G1 and G2 phases

    Science.gov (United States)

    Mao, Zhiyong; Ke, Zhonghe; Gorbunova, Vera; Seluanov, Andrei

    2012-01-01

    Most human somatic cells do not divide indefinitely but enter a terminal growth arrest termed replicative senescence. Replicatively senescent cells are generally believed to arrest in G1 or G0 stage of the cell cycle. While doing cell cycle analysis on three different lines of normal human fibroblasts we observed that 36-60% of the replicatively senescent cells had 4N DNA content. Only up to 5% of senescent cells had more than one nucleus ruling out the possibility that the 4N cell population were G1-arrested bi-nucleated cells. Furthermore, it is unlikely that the 4N cells are tetraploids, because actively dividing pre-senescent cultures lacked the 8N tetraploid G2 population. Collectively these results suggest that the 4N population consists of G2 arrested cells. The notion that a large fraction of senescent cell population is arrested in G2 is important for understanding the biology of replicative senescence. PMID:22745179

  6. Infrared-excess Source DSO/G2 Near the Galactic Center: Theory vs. Observations

    CERN Document Server

    Zajacek, Michal; Peissker, Florian; Karssen, Grischa D; Karas, Vladimir

    2015-01-01

    We monitored the Dusty S-cluster object (DSO/G2) during its closest approach to the Galactic Center supermassive black hole in 2014 with ESO VLT/SINFONI. We report on our findings, i.e. ionized-hydrogen emission from the DSO that remains spatially compact before and after the peribothron passage. The detection of DSO/G2 object as a compact single-peak emission line source is in contradiction with the original hypothesis of a core-less cloud that is necessarily tidally stretched, hence producing double-peak emission line profile around the pericentre passage. This strengthens the evidence that the DSO/G2 source is a dust-enshrouded young star. The accretion of material from the circumstellar disc onto the stellar surface can contribute significantly to the emission of Br$\\gamma$ line as well as to the observed large line width of the order of 10 angstroms.

  7. Gas cloud G2 can illuminate the black hole population near the galactic center.

    Science.gov (United States)

    Bartos, Imre; Haiman, Zoltán; Kocsis, Bence; Márka, Szabolcs

    2013-05-31

    Galactic nuclei are expected to be densely populated with stellar- and intermediate-mass black holes. Exploring this population will have important consequences for the observation prospects of gravitational waves as well as understanding galactic evolution. The gas cloud G2 currently approaching Sgr A* provides an unprecedented opportunity to probe the black hole and neutron star population of the Galactic nucleus. We examine the possibility of a G2-cloud-black-hole encounter and its detectability with current x-ray satellites, such as Chandra and NuSTAR. We find that multiple encounters are likely to occur close to the pericenter, which may be detectable upon favorable circumstances. This opportunity provides an additional important science case for leading x-ray observatories to closely follow G2 on its way to the nucleus.

  8. [Biological function and molecular mechanism of URI in HepG2 cells].

    Science.gov (United States)

    Zhou, Wei; Zhong, Yanyu; Wang, Hongmin; Yang, Sijun; Wei, Wenxiang

    2014-11-01

    To explore the effect and molecular mechanism of the unconventional prefoldin RPB5 interactor (URI) in hepatocellular carcinoma HepG2 cells. The cDNA sequence and shRNA of URI were obtained and sub-cloned into eukaryotic expression vectors. Then those vectors were transfected into HepG2 cells to obtain stable transfection cell line. The cell proliferation and anchor-independent growth in URI-overexpressing and knockdown HepG2 cells were determined by CCK-8 and soft agar colony assay. Flow cytometry was applied to detect the cell cycle and apoptosis of γ-ray irradiated cells. Apoptosis related genes were detected by Western blot. The pCDNA3.1-URI and pGPU6-URIi eukaryotic expression vectors were constructed successfully and corresponding stable transfection cell lines were obtained. Cell proliferation rates of the HepG2, pCDNA3.1-URI-HepG2 and pGPU6-URIi-HepG2 cells were (588.78 ± 32.12)%, (959.33 ± 58.8)% and (393.93 ± 39.7)%, respectively (P HepG2, pCDNA3.1-URI-HepG2 and pGPU6-URIi-HepG2 cells were 43 ± 7, 85 ± 5 and 20 ± 4 (P HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 0.92 ± 0.03, 1.11 ± 0.13 and 0.82 ± 0.01 (P HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 1.79 ± 0.12, 0.48 ± 0.01 and 2.20 ± 0.30 (P HepG2 cells, the relative protein expression levels of URI, Bax and Bcl-2 were 0.50 ± 0.04, 1.52 ± 0.20 and 0.38 ± 0.01 (P < 0.05), respectively. The expression of Bax was down-regulated and Bcl-2 was up-regulated in the URI-overexpressing cell line. However, on the contrary, expression of Bax was up-regulated and Bcl-2 was down-regulated in the URI-depleted cell line. URI may promote the growth of hepatocellular carcinoma cells via inhibition of cell proliferation and reducing the apoptosis in hepatocellular carcinoma cells in vitro. After the impairment of URI expression, the proliferation ability of hepatocellular carcinoma cells is suppressed and the ability to resist

  9. G2LC: Resources Autoscaling for Real Time Bioinformatics Applications in IaaS

    Directory of Open Access Journals (Sweden)

    Rongdong Hu

    2015-01-01

    Full Text Available Cloud computing has started to change the way how bioinformatics research is being carried out. Researchers who have taken advantage of this technology can process larger amounts of data and speed up scientific discovery. The variability in data volume results in variable computing requirements. Therefore, bioinformatics researchers are pursuing more reliable and efficient methods for conducting sequencing analyses. This paper proposes an automated resource provisioning method, G2LC, for bioinformatics applications in IaaS. It enables application to output the results in a real time manner. Its main purpose is to guarantee applications performance, while improving resource utilization. Real sequence searching data of BLAST is used to evaluate the effectiveness of G2LC. Experimental results show that G2LC guarantees the application performance, while resource is saved up to 20.14%.

  10. G2LC: Resources Autoscaling for Real Time Bioinformatics Applications in IaaS.

    Science.gov (United States)

    Hu, Rongdong; Liu, Guangming; Jiang, Jingfei; Wang, Lixin

    2015-01-01

    Cloud computing has started to change the way how bioinformatics research is being carried out. Researchers who have taken advantage of this technology can process larger amounts of data and speed up scientific discovery. The variability in data volume results in variable computing requirements. Therefore, bioinformatics researchers are pursuing more reliable and efficient methods for conducting sequencing analyses. This paper proposes an automated resource provisioning method, G2LC, for bioinformatics applications in IaaS. It enables application to output the results in a real time manner. Its main purpose is to guarantee applications performance, while improving resource utilization. Real sequence searching data of BLAST is used to evaluate the effectiveness of G2LC. Experimental results show that G2LC guarantees the application performance, while resource is saved up to 20.14%.

  11. Crystal Structure of a Dimerized Cockroach Allergen Bla g 2 Complexed with a Monoclonal Antibody

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mi; Gustchina, Alla; Alexandratos, Jerry; Wlodawer, Alexander; Wünschmann, Sabina; Kepley, Christopher L.; Chapman, Martin D.; Pomes, Anna (INDOOR Bio.); (VCU); (NIH)

    2008-09-03

    The crystal structure of a 1:1 complex between the German cockroach allergen Bla g 2 and the Fab' fragment of a monoclonal antibody 7C11 was solved at 2.8-{angstrom} resolution. Bla g 2 binds to the antibody through four loops that include residues 60-70, 83-86, 98-100, and 129-132. Cation-{pi} interactions exist between Lys-65, Arg-83, and Lys-132 in Bla g 2 and several tyrosines in 7C11. In the complex with Fab', Bla g 2 forms a dimer, which is stabilized by a quasi-four-helix bundle comprised of an {alpha}-helix and a helical turn from each allergen monomer, exhibiting a novel dimerization mode for an aspartic protease. A disulfide bridge between C51a and C113, unique to the aspartic protease family, connects the two helical elements within each Bla g 2 monomer, thus facilitating formation of the bundle. Mutation of these cysteines, as well as the residues Asn-52, Gln-110, and Ile-114, involved in hydrophobic interactions within the bundle, resulted in a protein that did not dimerize. The mutant proteins induced less {beta}-hexosaminidase release from mast cells than the wild-type Bla g 2, suggesting a functional role of dimerization in allergenicity. Because 7C11 shares a binding epitope with IgE, the information gained by analysis of the crystal structure of its complex provided guidance for site-directed mutagenesis of the allergen epitope. We have now identified key residues involved in IgE antibody binding; this information will be useful for the design of vaccines for immunotherapy.

  12. HepG2 cells recovered from apoptosis show altered drug responses and invasiveness

    Institute of Scientific and Technical Information of China (English)

    Shan-Shan Wang; Xin Xie; Chung Sing Timothy Wong

    2014-01-01

    BACKGROUND: Cancer  relapse,  associated  with  increased drug resistance and rate of metastasis, often follows completion of chemotherapy but the cancer escape mechanisms are still incompletely understood. Percutaneous ethanol injection (PEI) has been used for treating hepatocellular carcinoma (HCC) for decades, while the recurrence after PEI treatment remains a major limitation. Recent evidence mounted that cancer cells could survive from chemical induced apoptosis, suggesting a potential route through which cancer relapse may occur. This study focuses on the consequence of HepG2 recovery from ethanol-induced apoptotic event. METHODS: The  model  of  HepG2  recovery  from  ethanol-induced apoptotic event was established by live cell imaging, BrdU assay and Western blotting. MTT assay, wound healing assay and invasion assay were used to investigate the behavior of HepG2 after recovery. RESULTS: HepG2 cells could recover from ethanol-induced apoptosis. These cells changed their behaviors such as drug resistance, mobility and invasiveness. On average, the recovered HepG2 cell clones were found to be 46% more resistant to ethanol and 84% higher in mobility. The recovered clones became 58.2% more sensitive to 5-lfuorouracil. CONCLUSIONS: HepG2  cells  can  recover  from  ethanol-induced apoptotic event. These cells became more resistant to ethanol and more invasive. Although the recovered cell clones were more resistant to ethanol, they became more sensitive to 5-lfuorouracil treatment.

  13. CLA对HepG2细胞脂肪堆积的影响

    Institute of Scientific and Technical Information of China (English)

    张艳; 张丽; 张威

    2011-01-01

    目的 研究共轭亚油酸对H e p G2细胞中脂质沉积的影响.方法 以H e p G2细胞为研究对象,以不同浓度C L A(10μmol·L-1、50μmol·L-1、100μmol·L-1)作用细胞24小时,采用油红染色、RT-PCR等方法检测肝脏脂肪沉积、ACC mRNA表达,观察CLA对肝细胞内脂质沉积的影响.结果 CLA增加HepG2细胞中脂质沉积,50μmol·L-1CLA组细胞中红染脂滴与对照组相比明显增多;CL A使H e pG2细胞培养液中游离脂肪酸降低,50μm o l·L-1组的培养液中游离脂肪酸与对照组相比含量降低了50%(P<0.05);CLA增加HepG2细胞ACC mRNA的表达,ACC mRNA表达水平随CLA浓度增加而增高.结论 CLA可增加HepG2细胞的脂肪沉积;其机制可能与CLA能够改变肝细胞中ACC的表达有关.

  14. Comparative analysis of 3D culture methods on human HepG2 cells.

    Science.gov (United States)

    Luckert, Claudia; Schulz, Christina; Lehmann, Nadja; Thomas, Maria; Hofmann, Ute; Hammad, Seddik; Hengstler, Jan G; Braeuning, Albert; Lampen, Alfonso; Hessel, Stefanie

    2017-01-01

    Human primary hepatocytes represent a gold standard in in vitro liver research. Due to their low availability and high costs alternative liver cell models with comparable morphological and biochemical characteristics have come into focus. The human hepatocarcinoma cell line HepG2 is often used as a liver model for toxicity studies. However, under two-dimensional (2D) cultivation conditions the expression of xenobiotic-metabolizing enzymes and typical liver markers such as albumin is very low. Cultivation for 21 days in a three-dimensional (3D) Matrigel culture system has been reported to strongly increase the metabolic competence of HepG2 cells. In our present study we further compared HepG2 cell cultivation in three different 3D systems: collagen, Matrigel and Alvetex culture. Cell morphology, albumin secretion, cytochrome P450 monooxygenase enzyme activities, as well as gene expression of xenobiotic-metabolizing and liver-specific enzymes were analyzed after 3, 7, 14, and 21 days of cultivation. Our results show that the previously reported increase of metabolic competence of HepG2 cells is not primarily the result of 3D culture but a consequence of the duration of cultivation. HepG2 cells grown for 21 days in 2D monolayer exhibit comparable biochemical characteristics, CYP activities and gene expression patterns as all 3D culture systems used in our study. However, CYP activities did not reach the level of HepaRG cells. In conclusion, the increase of metabolic competence of the hepatocarcinoma cell line HepG2 is not due to 3D cultivation but rather a result of prolonged cultivation time.

  15. Butyrylcholinesterase expression is regulated by fatty acids in HepG2 cells.

    Science.gov (United States)

    Gok, Muslum; Zeybek, N Dilara; Bodur, Ebru

    2016-11-25

    Butyrylcholinesterase (BChE) is mostly associated with the detoxification of xenobiotics. In this study to analyze the involvement of BChE in lipid metabolism, linoleic acid (LA) and α-linolenic acid (ALA) were applied to HepG2 cells along with expression of wild type human BChE. After 48 h of these treatments WST-1 cell proliferation assay, FACS analysis, RT-PCR, Oil Red O staining and activity assays were performed. Application of high concentrations of LA to HepG2 cells without BChE transfection lead to detachment of the cells. The IC50 value LA was found as 149.3 μM whereas the IC50 value for ALA could not be calculated. Hence, in order to display minimal effects on cell viability, 5 μM was chosen as appropriate concentration for LA and ALA application to HepG2 cells. Transfection of wild-type BChE plasmid to HepG2 cells yielded increased BChE expression. Application of 5 μM ALA after BChE transfection to HepG2 cells resulted in increased expression of BChE. Although with this low concentration the number of apoptotic cells was decreased with ALA treatments, LA application did not cause a similar result with the same dose. Moreover ghost cell like property was observed in LA-treated cells. Application of ALA, on the other hand, led to an overall increase in cell numbers, BChE expression and activity. Our results indicate that BChE expression might be regulated by ALA in HepG2 cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Higgs boson mass and muon g -2 with strongly coupled vectorlike generations

    Science.gov (United States)

    Nishida, Michinobu; Yoshioka, Koichi

    2016-11-01

    We study the Higgs boson mass and the muon anomalous magnetic moment (the muon g -2 ) in a supersymmetric standard model with vectorlike generations. The infrared physics of the model is governed by strong renormalization-group effects of the gauge couplings. That leads to sizable extra Yukawa couplings of Higgs doublets between the second and vectorlike generations in both quark and lepton sectors. It is found with this property that there exist wide parameter regions where the Higgs boson mass and the muon g -2 are simultaneously explained.

  17. Updated pseudoscalar contributions to the hadronic light-by-light of the muon (g-2)

    CERN Document Server

    Sanchez-Puertas, Pablo

    2016-01-01

    In this work, we present our recent results on a new and alternative data-driven determination for the hadronic light-by-light pseudoscalar-pole contribution to the muon $(g-2)$. Our approach is based on Canterbury approximants, a rational approach to describe the required transition form factors, which provides a systematic and model-independent framework beyond traditional large-$N_c$ approaches. As a result, we obtain a competitive determination with errors according to future $(g-2)$ experiments including, for the first time, a well-defined systematic uncertainty.

  18. Gluon contribution to the structure function $g_{2}(x,Q^{2})$

    CERN Document Server

    Braun, V M; Manashov, A N

    2001-01-01

    We calculate the one-loop twist-3 gluon contribution to the flavor-singlet structure function g_2(x,Q^2) in polarized deep-inelastic scattering and find that it is dominated by the contribution of the three-gluon operator with the lowest anomalous dimension (for each moment N). The similar property was observed earlier for the nonsinglet distributions, although the reason is in our case different. The result is encouraging and suggests a simple evolution pattern of g_2(x,Q^2) in analogy with the conventional description of twist-2 parton distributions.

  19. High permissivity of human HepG2 hepatoma cells for influenza viruses.

    Science.gov (United States)

    Ollier, Laurence; Caramella, Anne; Giordanengo, Valérie; Lefebvre, Jean-Claude

    2004-12-01

    Human HepG2 hepatoma cells are highly permissive for influenza virus type A and type B, even without the addition of trypsin, and they exhibit a marked cytopathic effect. This property greatly facilitates the primary isolation of influenza viruses. Virus replication was significantly reduced by the plasmin(ogen)-specific inhibitor tranexamic acid, and this suggests a potential role played by the plasminogen/tissue plasminogen activator complex at the surface of HepG2 cells. This might represent a new approach for study of the interrelations of this complex with influenza viruses.

  20. Moduli of $G_2$ structures and the Strominger system in dimension 7

    CERN Document Server

    Clarke, Andrew; Tipler, Carl

    2016-01-01

    We consider $G_2$ structures with torsion coupled with $G_2$-instantons, on a compact $7$-dimensional manifold. The coupling is via an equation for $4$-forms which appears in supergravity and generalized geometry, known as the Bianchi identity. The resulting system of partial differential equations can be regarded as an analogue of the Strominger system in $7$-dimensions. We initiate the study of the moduli space of solutions and show that it is finite dimensional using elliptic operator theory. We also relate the associated geometric structures to generalized geometry.

  1. Constraints on Hidden Photon Models from Electron g-2 and Hydrogen Spectroscopy

    CERN Document Server

    Endo, Motoi; Mishima, Go

    2012-01-01

    The hidden photon model is one of the simplest models which can explain the anomaly of the muon anomalous magnetic moment (g-2). The experimental constraints are studied in detail, which come from the electron g-2 and the hydrogen transition frequencies. The input parameters are set carefully in order to take dark photon contributions into account and to prevent the analysis from being self-inconsistent. It is shown that the new analysis provides a constraint severer by more than one order of magnitude than the previous result.

  2. Selection of Secure Hyperelliptic Curves of g = 2 Based on a Subfield

    Institute of Scientific and Technical Information of China (English)

    张方国; 张福泰; 王育民

    2002-01-01

    In the implementation of hyperelliptic curve cryptosystems, a siginificant stepis the selection of secure hyperelliptic curves on which the Jacobian is constructed. In thispaper, we discuss the hyperelliptic curves of g = 2 such as v2 + uv = f and v2 + v = f(u)defined on GF(2τ). The curves defined on GF(4) and GF(8) are expanded to the curves definedon GF(4)κ and GF(8)t respectively, where 38 < k < 70, 25 < t < 50. We also find out all thesecure curves of g = 2 that are suitable for establishing cryptosystems.

  3. The calibration system of the new g-2 experiment at Fermilab

    Science.gov (United States)

    Anastasi, A.; Babusci, D.; Cantatore, G.; Cauz, D.; Corradi, G.; Dabagov, S.; Di Meo, P.; Di Sciascio, G.; Di Stefano, R.; Ferrari, C.; Fienberg, A. T.; Fioretti, A.; Gabbanini, C.; Hampai, D.; Hertzog, D. W.; Iacovacci, M.; Karuza, M.; Kaspar, J.; Marignetti, F.; Mastroianni, S.; Moricciani, D.; Pauletta, G.; Santi, L.; Venanzoni, G.

    2016-07-01

    The muon anomaly (g - 2) μ / 2 has been measured to 0.54 parts per million by E821 experiment at Brookhaven National Laboratory, and at present there is a 3-4 standard-deviation difference between the Standard Model prediction and the experimental value. A new muon g-2 experiment, E989, is being prepared at Fermilab that will improve the experimental error by a factor of four to clarify this difference. A central component to reach this fourfold improvement in accuracy is the high-precision laser calibration system which should monitor the gain fluctuations of the calorimeter photodetectors at 0.04% accuracy.

  4. SIMULATED PERFORMANCE OF THE PRODUCTION TARGET FOR THE MUON G-2 EXPERIMENT

    Energy Technology Data Exchange (ETDEWEB)

    Stratakis, D. [Fermilab; Convery, M. [Fermilab; Morgan, J. P. [Fermilab; Still, D. [Fermilab; Syphers, M. J. [Northern Illinois U.; Tishchenko, V. [Brookhaven Natl. Lab.

    2017-05-23

    The Muon g-2 Experiment plans to use the Fermilab Re-cycler Ring for forming the proton bunches that hit its pro-duction target. The proposed scheme uses one RF system, 80 kV of 2.5 MHz RF. In order to avoid bunch rotations in a mismatched bucket, the 2.5 MHz is ramped adiabatically from 3 to 80 kV in 90 ms. In this study, the interaction of the primary proton beam with the production target for the Muon g-2 Experiment is numerically examined.

  5. The conformal-Killing equation on G2 and Spin7 structures

    CERN Document Server

    David, Liana

    2010-01-01

    Let M be a 7-manifold with a G2-structure defined by \\phi \\in\\Omega^{3}_{+}(M). We prove that {\\phi} is conformal-Killing with respect to the associated metric g(\\phi) if and only if the G2-structure is nearly parallel. Let M be an 8-manifold with a Spin7-structure defined by \\psi \\in\\Omega^{4}_{+}(M). We prove that {\\psi} is conformal-Killing with respect to the associated metric g(\\psi) if and only if the Spin7-structure is parallel.

  6. Probing $(g-2)_{\\mu}$ at the LHC in the paradigm of R-parity violating MSSM

    CERN Document Server

    Chakraborty, Amit

    2015-01-01

    The measurement of the anomalous magnetic moment of the muon exhibits a long standing discrepancy compared to the Standard model prediction. In this paper we consider the framework of effective supersymmetric theory with relevant $R$-parity violating operators, which can provide substantially large anomalous magnetic moment of the muon. In addition, we point out that the implication of such operators satisfying muon $g-2$ are immense from the perspective of the LHC experiment, leading to a spectacular four muon final state. We propose an analysis in this particular channel which might help to settle the debate of $R$-parity violation as an probable explanation for $(g-2)_{\\mu}$.

  7. Demonstration of the presence of the "deleted" MIR122 gene in HepG2 cells.

    Science.gov (United States)

    Hamad, Ibrahim A Y; Fei, Yue; Kalea, Anastasia Z; Yin, Dan; Smith, Andrew J P; Palmen, Jutta; Humphries, Steve E; Talmud, Philippa J; Walker, Ann P

    2015-01-01

    MicroRNA 122 (miR-122) is highly expressed in the liver where it influences diverse biological processes and pathways, including hepatitis C virus replication and metabolism of iron and cholesterol. It is processed from a long non-coding primary transcript (~7.5 kb) and the gene has two evolutionarily-conserved regions containing the pri-mir-122 promoter and pre-mir-122 hairpin region. Several groups reported that the widely-used hepatocytic cell line HepG2 had deficient expression of miR-122, previously ascribed to deletion of the pre-mir-122 stem-loop region. We aimed to characterise this deletion by direct sequencing of 6078 bp containing the pri-mir-122 promoter and pre-mir-122 stem-loop region in HepG2 and Huh-7, a control hepatocytic cell line reported to express miR-122, supported by sequence analysis of cloned genomic DNA. In contrast to previous findings, the entire sequence was present in both cell lines. Ten SNPs were heterozygous in HepG2 indicating that DNA was present in two copies. Three validation isolates of HepG2 were sequenced, showing identical genotype to the original in two, whereas the third was different. Investigation of promoter chromatin status by FAIRE showed that Huh-7 cells had 6.2 ± 0.19- and 2.7 ± 0.01- fold more accessible chromatin at the proximal (HNF4α-binding) and distal DR1 transcription factor sites, compared to HepG2 cells (p=0.03 and 0.001, respectively). This was substantiated by ENCODE genome annotations, which showed a DNAse I hypersensitive site in the pri-mir-122 promoter in Huh-7 that was absent in HepG2 cells. While the origin of the reported deletion is unclear, cell lines should be obtained from a reputable source and used at low passage number to avoid discrepant results. Deficiency of miR-122 expression in HepG2 cells may be related to a relative deficiency of accessible promoter chromatin in HepG2 versus Huh-7 cells.

  8. Synthesis of apoptotic chalcone analogues in HepG2 human hepatocellular carcinoma cells.

    Science.gov (United States)

    Park, Cheon-Soo; Ahn, Yongchel; Lee, Dahae; Moon, Sung Won; Kim, Ki Hyun; Yamabe, Noriko; Hwang, Gwi Seo; Jang, Hyuk Jai; Lee, Heesu; Kang, Ki Sung; Lee, Jae Wook

    2015-12-15

    Eight chalcone analogues were prepared and evaluated for their cytotoxic effects in human hepatoma HepG2 cells. Compound 5 had a potent cytotoxic effect. The percentage of apoptotic cells was significantly higher in compound 5-treated cells than in control cells. Exposure to compound 5 for 24h induced cleavage of caspase-8 and -3, and poly (ADP-ribose) polymerase (PARP). Our findings suggest that compound 5 is the active chalcone analogue that contributes to cell death in HepG2 cells via the extrinsic apoptotic pathway.

  9. Frequency Shifts Induced by Field Gradients in Muon $g-2$ Experiments

    CERN Document Server

    Nouri, N; Golub, R; Plaster, B

    2016-01-01

    Two prominent efforts aimed at probing beyond Standard Model physics, searches for a neutron electric dipole moment (EDM) and measurements of the muon $g-2$ anomalous magnetic moment, employ spin precession techniques. In the most recent neutron EDM experiment, frequency shifts induced by magnetic field gradients and $\\mathbf{E} \\times \\mathbf{v}$ motional fields were a significant source of systematic error. We consider the possibility of a similar effect in the most recent muon $g-2$ experiment, and find that such an effect could potentially be as large as $\\sim 1$ ppm fractional error, to be compared with the reported $\\sim 0.5$ ppm error.

  10. TMEM2 inhibits hepatitis B virus infection in HepG2 and HepG2.2.15 cells by activating the JAK-STAT signaling pathway.

    Science.gov (United States)

    Zhu, X; Xie, C; Li, Y-M; Huang, Z-L; Zhao, Q-Y; Hu, Z-X; Wang, P-P; Gu, Y-R; Gao, Z-L; Peng, L

    2016-06-02

    We have previously observed the downregulation of TMEM2 in the liver tissue of patients with chronic hepatitis B virus (HBV) infection and in HepG2.2.15 cells with HBV genomic DNA. In the present study, we investigated the role and mechanism of TMEM2 in HepG2 and HepG2.2.15 during HBV infection HepG2 and HepG2.2.15. HepG2 shTMEM2 cells with stable TMEM2 knockdown and HepG2 TMEM2 and HepG2.2.15 TMEM2 cells with stable TMEM2 overexpression were established using lentivirus vectors. We observed reduced expression of TMEM2 in HBV-infected liver tissues and HepG2.2.15 cells. HBsAg, HBcAg, HBV DNA, and HBV cccDNA levels were significantly increased in HepG2 shTMEM2 cells but decreased in HepG2 TMEM2 and HepG2.2.15 TMEM2 cells compared with naive HepG2 cells. On the basis of the western blotting results, the JAK-STAT signaling pathway was inhibited in HepG2 shTMEM2 cells but activated in HepG2 TMEM2 and HepG2.2.15 TMEM2 cells. In addition, reduced and increased expression of the antiviral proteins MxA and OAS1 was observed in TMEM2-silenced cells (HepG2 shTMEM2 cells) and TMEM2-overexpressing cells (HepG2 TMEM2 and HepG2.2.15 TMEM2 cells), respectively. The expression of Interferon regulatory factor 9 (IRF9) was not affected by TMEM2. However, we found that overexpression and knockdown of TMEM2, respectively, promoted and inhibited importation of IRF9 into nuclei. The luciferase reporter assay showed that IRF9 nuclear translocation affected interferon-stimulated response element activities. In addition, the inhibitory effects of TMEM2 on HBV infection in HepG2 shTMEM2 cells was significantly enhanced by pre-treatment with interferon but significantly inhibited in HepG2.2.15 TMEM2 cells by pre-treatment with JAK1 inhibitor. TMEM2 inhibits HBV infection in HepG2 and HepG2.2.15 by activating the JAK-STAT signaling pathway.

  11. TMEM2 inhibits hepatitis B virus infection in HepG2 and HepG2.2.15 cells by activating the JAK–STAT signaling pathway

    Science.gov (United States)

    Zhu, X; Xie, C; Li, Y-m; Huang, Z-l; Zhao, Q-y; Hu, Z-x; Wang, P-p; Gu, Y-r; Gao, Z-l; Peng, L

    2016-01-01

    We have previously observed the downregulation of TMEM2 in the liver tissue of patients with chronic hepatitis B virus (HBV) infection and in HepG2.2.15 cells with HBV genomic DNA. In the present study, we investigated the role and mechanism of TMEM2 in HepG2 and HepG2.2.15 during HBV infection HepG2 and HepG2.2.15. HepG2 shTMEM2 cells with stable TMEM2 knockdown and HepG2 TMEM2 and HepG2.2.15 TMEM2 cells with stable TMEM2 overexpression were established using lentivirus vectors. We observed reduced expression of TMEM2 in HBV-infected liver tissues and HepG2.2.15 cells. HBsAg, HBcAg, HBV DNA, and HBV cccDNA levels were significantly increased in HepG2 shTMEM2 cells but decreased in HepG2 TMEM2 and HepG2.2.15 TMEM2 cells compared with naive HepG2 cells. On the basis of the western blotting results, the JAK–STAT signaling pathway was inhibited in HepG2 shTMEM2 cells but activated in HepG2 TMEM2 and HepG2.2.15 TMEM2 cells. In addition, reduced and increased expression of the antiviral proteins MxA and OAS1 was observed in TMEM2-silenced cells (HepG2 shTMEM2 cells) and TMEM2-overexpressing cells (HepG2 TMEM2 and HepG2.2.15 TMEM2 cells), respectively. The expression of Interferon regulatory factor 9 (IRF9) was not affected by TMEM2. However, we found that overexpression and knockdown of TMEM2, respectively, promoted and inhibited importation of IRF9 into nuclei. The luciferase reporter assay showed that IRF9 nuclear translocation affected interferon-stimulated response element activities. In addition, the inhibitory effects of TMEM2 on HBV infection in HepG2 shTMEM2 cells was significantly enhanced by pre-treatment with interferon but significantly inhibited in HepG2.2.15 TMEM2 cells by pre-treatment with JAK1 inhibitor. TMEM2 inhibits HBV infection in HepG2 and HepG2.2.15 by activating the JAK–STAT signaling pathway. PMID:27253403

  12. The Tenth-Order QED Contribution to the Lepton g-2: Evaluation of Dominant $\\alpha^5$ Terms of Muon g-2

    CERN Document Server

    Kinoshita, T

    2006-01-01

    The QED contribution to the anomalous magnetic moments of electron and muon are known very precisely up to the order $\\alpha^4$. However, the knowledge of $\\alpha^5$ term will also be required when the precision of measurement improves further. This paper reports the first systematic attempt to evaluate the $\\alpha^5$ term. Feynman diagrams contributing to this term can be classified into six gauge-invariant sets which can be subdivided further into 32 gauge-invariant subsets. Thus far we have numerically evaluated all integrals of 17 gauge-invariant subsets which contain light-by-light-scattering subdiagrams and/or vacuum-polarization subdiagrams. They cover most of leading terms of muon $g-2$ and lead to a preliminary result 652 (20) $(\\alpha/\\pi )^5$, which is 8.5 times more precise than the old estimate.

  13. A new measurement of the leading hadronic corrections to the muon g-2*

    Directory of Open Access Journals (Sweden)

    Trentadue Luca

    2016-01-01

    Full Text Available A novel approach to determine the leading hadronic corrections to the muon g-2 is proposed. It consists in a measurement of the effective electromagnetic coupling in the space-like region. This method may become feasible at flavor factories resulting in a determination potentially competitive with the dispersive approach via time-like data.

  14. Three-dimensional spiral injection scheme for the g-2/EDM experiment at J-PARC

    Science.gov (United States)

    Iinuma, Hiromi; Nakayama, Hisayoshi; Oide, Katsunobu; Sasaki, Ken-ichi; Saito, Naohito; Mibe, Tsutomu; Abe, Mitsushi

    2016-10-01

    A newly developed three-dimensional spiral injection scheme for beam insertion into a solenoidal storage ring is reported. A new planned muon g-2/EDM experiment at J-PARC aims to measure g - 2 to a factor of 5 better statistical precision and a factor of 100 better sensitivity for the electric dipole moment (EDM) measurement compared to previous experiments. The J-PARC experiment will use a 3-T MRI solenoid magnet as the muon storage ring with a 0.66 m diameter to achieve a 1-ppm level of local uniformity. The previous g - 2 injection scheme is not applicable for beam injection into a small ring. The new scheme provides a smooth injection utilizing a radial solenoidal fringe field, without causing an error field in the storage volume. The expected storage efficiency is 80% and over, which is to be compared to 3.5% for the previous g - 2 experiment. In addition, the ability to control the storage plane is important for the EDM measurement. In this paper, we introduce the conceptual design and required beam parameters in terms of Twiss functions and the expected injection efficiency.

  15. Staphylococcus aureus Lpl Lipoproteins Delay G2/M Phase Transition in HeLa Cells.

    Science.gov (United States)

    Nguyen, Minh-Thu; Deplanche, Martine; Nega, Mulugeta; Le Loir, Yves; Peisl, Loulou; Götz, Friedrich; Berkova, Nadia

    2016-01-01

    The cell cycle is an ordered set of events, leading to cell growth and division into two daughter cells. The eukaryotic cell cycle consists of interphase (G1, S, and G2 phases), followed by the mitotic phase and G0 phase. Many bacterial pathogens secrete cyclomodulins that interfere with the host cell cycle. In Staphylococcus aureus four cyclomodulins have been described so far that all represent toxins and are secreted into the culture supernatant. Here we show that the membrane-anchored lipoprotein-like proteins (Lpl), encoded on a genomic island called νSaα, interact with the cell cycle of HeLa cells. By comparing wild type and lpl deletion mutant it turned out that the lpl cluster is causative for the G2/M phase transition delay and also contributes to increased invasion frequency. The lipoprotein Lpl1, a representative of the lpl cluster, also caused G2/M phase transition delay. Interestingly, the lipid modification, which is essential for TLR2 signaling and activation of the immune system, is not necessary for cyclomodulin activity. Unlike the other staphylococcal cyclomodulins Lpl1 shows no cytotoxicity even at high concentrations. As all Lpl proteins are highly conserved there might be a common function that is accentuated by their multiplicity in a tandem gene cluster. The cell surface localized Lpls' suggests a correlation between G2/M phase transition delay and host cell invasion.

  16. Pathways for Genome Integrity in G2 Phase of the Cell Cycle

    Directory of Open Access Journals (Sweden)

    Claus Storgaard Sørensen

    2012-11-01

    Full Text Available The maintenance of genome integrity is important for normal cellular functions, organism development and the prevention of diseases, such as cancer. Cellular pathways respond immediately to DNA breaks leading to the initiation of a multi-facetted DNA damage response, which leads to DNA repair and cell cycle arrest. Cell cycle checkpoints provide the cell time to complete replication and repair the DNA damage before it can continue to the next cell cycle phase. The G2/M checkpoint plays an especially important role in ensuring the propagation of error-free copies of the genome to each daughter cell. Here, we review recent progress in our understanding of DNA repair and checkpoint pathways in late S and G2 phases. This review will first describe the current understanding of normal cell cycle progression through G2 phase to mitosis. It will also discuss the DNA damage response including cell cycle checkpoint control and DNA double-strand break repair. Finally, we discuss the emerging concept that DNA repair pathways play a major role in the G2/M checkpoint pathway thereby blocking cell division as long as DNA lesions are present.

  17. CDK-1 Inhibition in G2 Stabilizes Kinetochore-Microtubules in the following Mitosis.

    Science.gov (United States)

    Gayek, A Sophia; Ohi, Ryoma

    2016-01-01

    Cell proliferation is driven by cyclical activation of cyclin-dependent kinases (CDKs), which produce distinct biochemical cell cycle phases. Mitosis (M phase) is orchestrated by CDK-1, complexed with mitotic cyclins. During M phase, chromosomes are segregated by a bipolar array of microtubules called the mitotic spindle. The essential bipolarity of the mitotic spindle is established by the kinesin-5 Eg5, but factors influencing the maintenance of spindle bipolarity are not fully understood. Here, we describe an unexpected link between inhibiting CDK-1 before mitosis and bipolar spindle maintenance. Spindles in human RPE-1 cells normally collapse to monopolar structures when Eg5 is inhibited at metaphase. However, we found that inhibition of CDK-1 in the G2 phase of the cell cycle improved the ability of RPE-1 cells to maintain spindle bipolarity without Eg5 activity in the mitosis immediately after release from CDK-1 inhibition. This improved bipolarity maintenance correlated with an increase in the stability of kinetochore-microtubules, the subset of microtubules that link chromosomes to the spindle. The improvement in bipolarity maintenance after CDK-1 inhibition in G2 required both the kinesin-12 Kif15 and increased stability of kinetochore-microtubules. Consistent with increased kinetochore-microtubule stability, we find that inhibition of CDK-1 in G2 impairs mitotic fidelity by increasing the incidence of lagging chromosomes in anaphase. These results suggest that inhibition of CDK-1 in G2 causes unpredicted effects in mitosis, even after CDK-1 inhibition is relieved.

  18. Recombination between G2 and G6 strains of rabbit hemorrhagic disease virus (RHDV) in China.

    Science.gov (United States)

    Hu, Bo; Wang, Fang; Fan, Zhiyu; Song, Yanhua; Abrantes, Joana; Zuo, Yuanyuan; Esteves, Pedro J

    2017-01-01

    Rabbit hemorrhagic disease (RHD) is an acute fatal disease caused by the lagovirus rabbit hemorrhagic disease virus (RHDV), which was first reported in 1984 in China. Genetic characterization of RHDV has demonstrated that two different genogroups (G2 and G6) are present in China. To gain a better understanding of the molecular evolution of RHDV, we searched for recombination events by analyzing all full-length RHDV capsid VP60 sequences of Chinese isolates belonging to the genogroups 2 and 6. Our results revealed a recombinant origin for the NanBu/China/2011 isolate. This recombination event occurred between G2 and G6 strains with two breakpoints located at nucleotide positions 393 and 1079 of the VP60 sequence. Phylogenetically, the NanBu/China/2011 strain clustered with genogroup G6 in the entire capsid gene sequence except in the fragment between nucleotides 394 and 1078, where it clustered with genogroup G2. As the consequences of the presence of a G2/G6 recombinant strain in China are unpredictable, the circulation of RHDV in the populations should be carefully monitored.

  19. Staphylococcus aureus Lpl Lipoproteins Delay G2/M Phase Transition in HeLa Cells

    Science.gov (United States)

    Nguyen, Minh-Thu; Deplanche, Martine; Nega, Mulugeta; Le Loir, Yves; Peisl, Loulou; Götz, Friedrich; Berkova, Nadia

    2016-01-01

    The cell cycle is an ordered set of events, leading to cell growth and division into two daughter cells. The eukaryotic cell cycle consists of interphase (G1, S, and G2 phases), followed by the mitotic phase and G0 phase. Many bacterial pathogens secrete cyclomodulins that interfere with the host cell cycle. In Staphylococcus aureus four cyclomodulins have been described so far that all represent toxins and are secreted into the culture supernatant. Here we show that the membrane-anchored lipoprotein-like proteins (Lpl), encoded on a genomic island called νSaα, interact with the cell cycle of HeLa cells. By comparing wild type and lpl deletion mutant it turned out that the lpl cluster is causative for the G2/M phase transition delay and also contributes to increased invasion frequency. The lipoprotein Lpl1, a representative of the lpl cluster, also caused G2/M phase transition delay. Interestingly, the lipid modification, which is essential for TLR2 signaling and activation of the immune system, is not necessary for cyclomodulin activity. Unlike the other staphylococcal cyclomodulins Lpl1 shows no cytotoxicity even at high concentrations. As all Lpl proteins are highly conserved there might be a common function that is accentuated by their multiplicity in a tandem gene cluster. The cell surface localized Lpls' suggests a correlation between G2/M phase transition delay and host cell invasion. PMID:28083519

  20. Colliding with G2 near the Galactic Centre: a geometrical approach

    CERN Document Server

    Marcos, R de la Fuente

    2013-01-01

    The object G2 will pass within nearly 100 au from Sgr A* in 2014. Due to its very short periapse, the study of the dynamical evolution of this object in the short-term future may offer some insight into the region surrounding the supermassive black hole at the centre of the Galaxy. With this scenario in mind, it has recently been proposed by Bartos et al. (arXiv:1302.3220) that, prior to its perinigricon, G2 will likely experience multiple encounters with members of the black hole and neutron star populations believed to orbit near the Galactic Centre. Here, we further explore this possibility and study the general case for collisions with the G2 object using the latest orbital solutions provided by Phifer et al. (arXiv:1304.5280) and Gillessen et al., (arXiv:1306.1374) and a Monte Carlo approach to estimate the minimum orbit intersection distance (MOID) with G2 as a function of the orbital parameters of the incoming body. Our results indicate that encounters at distances closer than 100 au started to become ...

  1. Asymptotical small-x behaviour of the spin structure functions $g_1$ and $g_2$

    CERN Document Server

    Ermolaev, B I

    1997-01-01

    We show that for small x and in the double logarithmic approximation (DLA) g_2 can be expressed through derivative of g_1 with respect to logarithm of the QCD coupling. Therefore the small-x behavior of the both structure functions is similar. The analytical expression for flavor nonsinglet structure function g_1 is presented and its asymptotical behaviour is calculated.

  2. PPARγ pathway activation results in apoptosis and COX-2 inhibition in HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Ming-Yi Li; Hua Deng; Jia-Ming Zhao; Dong Dai; Xiao-Yu Tan

    2003-01-01

    AIM: To investigate whether troglitazone (TGZ), theperoxisome proliferator-activated receptor (PPAR) gammaligand, can induce apoptosis and inhibit cell proliferation inhuman liver cancer cell line HepG2 and to explore themolecular mechanisms. METHODS: [3-(4,5)-dimethyithiazol-2-yl]-2,5-diphenyltetrazolium bromide (NTT), [3H] Thymidine incorporation,Hochest33258 staining, DNA ladder, enzyme-linkedimmunosorbent assay (ELISA), RT-PCR, Northern and Western blotting analyses were employed to investigate the effect of TGZ on HepG2 cells and related molecular mechanisms.RESULTS: TGZ was found to inhibit the growth of HepG2cells and to induce apoptosis. During the process, the expression of COX-2 mRNA and protein and Bcl-2 protein was down-regulated, while that of Bax and Bak proteins was up-regulated, and the activity of caspase-3 was elevated.Furthermore, the level of PGE2 was decreased transiently after 12 h of treatment with 30 gM troglitazone. CONCLUSION: TGZ inhibits cell proliferation and induces apoptosis in HepG2 cells, which may be associated with the activation of caspase-3-like proteases, down-regulation of the expression of COX-2 mRNA and protein, Bcl-2 protein,the elevation of PGE2 levels, and up-regulation of the expressions of Bax and Bak proteins.

  3. Octreotide induces caspase activation and apoptosis inhuman hepatoma HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Nikos J Tsagarakis; Ioannis Drygiannakis; Antonis G Batistakis; George Kolios; Elias A Kouroumalis

    2011-01-01

    AIM: To investigate the role of octreotide on cellular proliferation and apoptosis of human hepatoma (HepG2) cells.METHODS: We studied cellular proliferation, apoptosis and the possible internal caspase-mediated apoptosis pathway involved, after treatment of HepG2 carcinomacells with octreotide in comparison with the apoptosis caused by tumor necrosis factor-α (TNF-α). Activities of caspase-3, caspase-9, caspase-8 and caspase-2 were studied, while apoptosis was investigated through detection of DNA fragmentation and through identification of apoptotic cells with the annexin-V/propidium iodide flow cytometric method.RESULTS: After an initial increase in HepG2 cellular proliferation, a significant inhibition was observed with 10-8 mol/L octreotide, while TNF-α dose-dependentlydecreased proliferation. Early and late apoptosis was significantly increased with both substances. Octreotide significantly increased caspase-3, caspase-8 andcaspase-2 activity. TNF-α significantly increased only caspase-2. Cellular proliferation was decreased after treatment with octreotide or TNF-α alone but, in contrast to TNF-α, octreotide decreased proliferation onlyat concentrations of 10-8 mol/L, while lower concentrations increased proliferation.CONCLUSION: Our findings are suggestive of caspasemediated signaling pathways of octreotide antitumor activity in HepG2 cells, and indicate that measurementsof serum octreotide levels may be important, at least in clinical trials, to verify optimal therapeutic drug concentrations.

  4. RESEARCH OF SYNERGETIC RELIABILITY OF PEARLITE-REDUCED STRUCTURAL STEEL 09G2FB

    Directory of Open Access Journals (Sweden)

    Gustov Yuriy Ivanovich

    2012-10-01

    Full Text Available The primary objective of the research is the synergetic reliability of perlite-reduced structural steel 09G2FB exposed to various thermal and mechanical treatments. In the aftermath of the above exposure, the steel in question has proved to assume a set of strength-related and plastic mechanical properties (σσδ and ψ.

  5. Knockdown of nucleophosmin induces S-phase arrest in HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Qing-Qing Wang; Zhi-Yi Zhang; Jian-Yong Xiao; Chun Yi; Lin-Zi Li; Yan Huang; Jing-Ping Yun

    2011-01-01

    Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation,apoptosis,ribosome assembly,and centrosome duplication; however,the role of NPM in cell cycle regulation is not well characterized.We investigated the mechanism by which NPM is involved in cell cycle regulation.NPM was knocked down using siRNA in HepG2 hepatoblastoma cells.NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining.Expression of NPM and other factors involved in cell cycle regulation was examined by Westem blotting.Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2'-deoxyuddine (EdU) incorporation.Cell proliferation was quantified by the MTT assay.Knockdown of NPM increased the percentage of HepG2 calls in S phase and led to decreased expression of P53 and P21Cp1/WAF1.S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment.Furthermore,knockdown of NPM abrogated ActD-induced G2/M phase call cycle arrest.Taken together,these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.

  6. Effects of elaidic acid in a HepG2-SF liver cell model

    DEFF Research Database (Denmark)

    Hansen, Toke Peter Krogager

    lipidmetabolismen når HepG2-SF celler blev inkuberet med elaidinsyre sammenlignet med oleinsyre eller stearinsyre. Den mest fremtrædende ændring var en opregulering af enzymer som syntetiserer kolesterol og fedtsyrer, hvilken indikerede aktivering af sterol regulatory element-binding proteins (SREBPs). Dog blev...

  7. Curcumin and (-)-epigallocatechin-3-gallate attenuate acrylamide-induced proliferation in HepG2 cells.

    Science.gov (United States)

    Shan, Xiaoyun; Li, Yuan; Meng, Xulian; Wang, Pengqi; Jiang, Pan; Feng, Qing

    2014-04-01

    Acrylamide, a proven rodent carcinogen, is present in carbohydrate-rich food heated at high temperatures. It can be metabolized into glycidamide mainly by cytochrome P450 2E1 (CYP2E1). The fact that acrylamide is a potential carcinogen to human-beings draws public attention recently. This study aimed to elucidate the effect of acrylamide at low doses on proliferation of HepG2 cells, and to test whether the two well-studied chemopreventive agents, curcumin and (-)-epigallocatechin-3-gallate (EGCG), would have antagonistic effects against acrylamide. The results showed that lower concentration of acrylamide (⩽100μM) significantly increased the proliferation of HepG2 cells, but not of the other cancer cells (MDA-231, HeLa, A549, and PC-3). Only in HepG2 cells, low concentration of acrylamide was able to induce CYP2E1 expression significantly. Knockdown of CYP2E1 restrained acrylamide to increase viability of HepG2 cells. In addition, acrylamide raised expression of epidermal growth factor receptor (EGFR), cyclin D1 and nuclear factor-κB (NF-κB), which contributed to cell proliferation. Both curcumin and EGCG effectively reduced acrylamide-induced proliferation, as well as protein expression of CYP2E1, EGFR, cyclin D1 and NF-κB. All these results suggest that low concentration of acrylamide may contribute to progression of hepatocellular carcinoma (HCC). Curcumin or EGCG could prevent acrylamide triggering this effect.

  8. Hyperglycemia and anthocyanin inhibit quercetin metabolism in HepG2 cells

    Science.gov (United States)

    A high glucose (Glu) milieu promotes generation of reactive oxygen species, which may not only cause cellular damage, but also modulate phase II enzymes that are responsible for the metabolism of flavonoids. Thus, we examined the effect of a high Glu milieu on quercetin (Q) metabolism in HepG2 cells...

  9. Mangiferin: A xanthone attenuates mercury chloride induced cytotoxicity and genotoxicity in HepG2 cells.

    Science.gov (United States)

    Kaivalya, Mudholkar; Nageshwar Rao, B N; Satish Rao, B S

    2011-01-01

    Mangiferin (MGN), a dietary C-glucosylxanthone present in Mangifera indica, is known to possess a spectrum of beneficial pharmacological properties. This study demonstrates antigenotoxic potential of MGN against mercuric chloride (HgCl2)-induced genotoxicity in HepG2 cell line. Treatment of HepG2 cells with various concentrations of HgCl2 for 3 h caused a dose-dependent increase in micronuclei frequency and elevation in DNA strand breaks (olive tail moment and tail DNA). Pretreatment with MGN significantly (p inhibited HgCl2 -induced (20 µM for 30 h) DNA damage. An optimal antigenotoxic effect of MGN, both in micronuclei and comet assay, was observed at a concentration of 50 µM. Furthermore, HepG2 cells treated with various concentrations of HgCl2 resulted in a dose-dependent increase in the dichlorofluorescein fluorescence, indicating an increase in the generation of reactive oxygen species (ROS). However, MGN by itself failed to generate ROS at a concentration of 50 µM, whereas it could significantly decrease HgCl2 -induced ROS. Our study clearly demonstrates that MGN pretreatment reduced the HgCl2-induced DNA damage in HepG2 cells, thus demonstrating the genoprotective potential of MGN, which is mediated mainly by the inhibition of oxidative stress.

  10. Zero Action on Perfect Crystals for U_q(G_2^{(1)})

    CERN Document Server

    Misra, Kailash C; Okado, Masato

    2009-01-01

    The explicit zero action of Kashiwara operators on the U'_q(G_2^{(1)})-crystal B_l constructed by Yamane are presented by using a similarity technique from that of a U'_q(D_4^{(3)})-crystal. It is shown that these crystals form a coherent family of perfect crystals.

  11. On the Perplexingly Low Rate of Transport of IgG2 across the Human Placenta

    NARCIS (Netherlands)

    Einarsdottir, Helga K.; Stapleton, Nigel M.; Scherjon, Sicco; Andersen, Jan Terje; Rispens, Theo; van der Schoot, C. Ellen; Vidarsson, Gestur

    2014-01-01

    The neonatal receptor, FcRn, mediates both serum half-life extension as well as active transport of maternal IgG to the fetus during pregnancy. Therefore, transport efficiency and half-life go hand-in-hand. However, while the half-life of the human IgG2 subclass is comparable to IgG1, the placental

  12. Analysis of the hadronic light-by-light contributions to the muon g - 2

    NARCIS (Netherlands)

    Bijnens, Johan; Pallante, Elisabetta; Prades, Joaquim

    1996-01-01

    We calculate the hadronic light-by-light contributions to the muon g - 2. We use both 1/Nc and chiral counting to organize the calculation. Then we calculate the leading and next-to-leading order in the 1/Nc expansion low energy contributions using the Extended Nambu-Jona-Lasinio model as hadronic m

  13. Surface Grafted Glycopolymer Brushes to Enhance Selective Adhesion of HepG2 Cells

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Jensen, Bettina Elisabeth Brøgger; Shimizu, Kyoko;

    2013-01-01

    of the cell periphery. On the other hand the cells on bare glass substrate display spheroid morphology. Further analysis using ToF-SIMS imaging shows that the HepG2 cells on glycopolymer surfaces is enriched with protein fragment along the cell periphery which is absent in the case of cells on bare glass...

  14. Polarization Restricts Hepatitis C Virus Entry into HepG2 Hepatoma Cells

    NARCIS (Netherlands)

    Mee, Christopher J.; Harris, Helen J.; Farquhar, Michelle J.; Wilson, Garrick; Reynolds, Gary; Davis, Christopher; van IJzendoorn, Sven C. D.; Balfe, Peter; McKeating, Jane A.

    2009-01-01

    The primary reservoir for hepatitis C virus (HCV) replication is believed to be hepatocytes, which are highly polarized with tight junctions (TJ) separating their basolateral and apical domains. HepG2 cells develop polarity over time, resulting in the formation and remodeling of bile canalicular

  15. BRCA1 and its phosphorylation involved in caffeine-inhibitable event upstream of G2 checkpoint

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Caffeine,which specifically inhibits ATM/ATR kinases,efficiently abrogates the ionizing radiation(IR)-induced G2 arrest and increases the sensitivity of various tumor cells to IR.Mechanisms for the effect of caffeine remain to be elucidated.As a target of ATM/ATR kinases,BRCA1 becomes activated and phosphorylated in response to IR.Thus,in this work,we investigated the possible role of BRCA1 in the effect of caffeine on G2 checkpoint and observed how BRCA1 phosphorylation was regulated in this process.For these purposes,the BRCA1 protein level and the phosphorylation states were analyzed by Western blotting by using an antibody against BRCA1 and phospho-specific antibodies against Ser-1423 and Ser-1524 residues in cells exposed to a combination of IR and caffeine.The results showed that caffeine down-regulated IR-induced BRCA1 expression and specifically abolished BRCA1 phosphorylation of Ser-1524,which was followed by an override of G2 arrest by caffeine.In addition,the ability of BRCA1 to transactivate p21 may be required for MCF-7 but not necessary for Hela response to caffeine.These data suggest that BRCA1 may be a potential target of caffeine.BRCA1 and its phosphorylation are most likely to be involved in the caffeine-inhibitable event upstream of G2 arrest.

  16. Oceanic Climatology in the Coupled Model FGOALS-g2:Improvements and Biases

    Institute of Scientific and Technical Information of China (English)

    LIN Pengfei; YU Yongqiang; LIU Hailong

    2013-01-01

    The present study examines simulated oceanic climatology in the Flexible Global Ocean-Atmosphere-Land System model,Grid-point Version 2 (FGOALS-g2) forced by historical external forcing data.The oceanic temperatures and circulations in FGOALS-g2 were found to be comparable to those observed,and substantially improved compared to those simulated by the previous version,FGOALS-g1.0.Compared with simulations by FGOALS-g1.0,the shallow mixed layer depths were better captured in the eastern Atlantic and Pacific Ocean in FGOALS-g2.In the high latitudes of the Northern Hemisphere,the cold biases of SST were about 1℃ 5℃ smaller in FGOALS-g2.The associated sea ice distributions and their seasonal cycles were more realistic in FGOALS-g2.The pattern of Atlantic Meridional Overturning Circulation (AMOC) was better simulated in FGOALS-g2,although its magnitude was larger than that found in observed data.The simulated Antarctic Circumpolar Current (ACC) transport was about 140 Sv through the Drake Passage,which is close to that observed.Moreover,Antarctic Intermediate Water (AAIW) was better captured in FGOALS-g2.However,large SST cold biases (>3℃) were still found to exist around major western boundary currents and in the Barents Sea,which can be explained by excessively strong oceanic cold advection and unresolved processes owing to the coarse resolution.In the Indo-Pacific warm pool,the cold biases were partly related to the excessive loss of heat from the ocean.Along the eastern coast in the Atlantic and Pacific Oceans,the warm biases were due to overestimation of shortwave radiation.In the Indian Ocean and Southern Ocean,the surface fresh biases were mainly due to the biases of precipitation.In the tropical Pacific Ocean,the surface fresh biases (>2 psu) were mainly caused by excessive precipitation and oceanic advection.In theIndo-Pacific Ocean,fresh biases were also found to dominate in the upper 1000 m,except in the northeastern Indian Ocean.There were warm and

  17. Quarter variation and correlations of colostrum albumin, immunoglobulin G1 and G2 in dairy cows.

    Science.gov (United States)

    Samarütel, Jaak; Baumrucker, Craig R; Gross, Josef J; Dechow, Chad D; Bruckmaier, Rupert M

    2016-05-01

    A high variation in immunoglobulin G1 (IgG1) concentration in first milked quarter colostrum has been reported, but BSA quarter colostrum variation is not known. The occurrence of serum albumin in milk has been attributed to increased blood-milk barrier penetration. Reports of serum albumin binding to the Fc Receptor of the neonate, the receptor thought to be responsible for IgG1 transcytosis, suggested that a correlation with the appearance of IgG1 in colostrum of dairy cows was likely. The objective of the study was to establish the quarter colostrum concentration and mass of immunoglobulins and serum albumin. First colostrum was quarter collected within 4 h of parturition from healthy udders of 31 multiparous dairy cows. Individual quarter colostrum weight was determined and a sample of each was frozen for subsequent analysis. Concentrations of immunoglobulin G1, G2, and BSA were measured by ELISA and total mass of components was calculated. In addition, colostrum was also analysed for L-lactate dehydrogenase activity. Analysis of concentration and mass of BSA, immunoglobulin G1, G2 established that the quarter variations were different by cow, quarter and quarter within cow. Partial correlations corrected for colostrum weight indicated that BSA and IgG2 concentration and mass are closely correlated while that of BSA and IgG1 concentration and mass exhibited no correlation suggesting that BSA and IgG1 may have different transport mechanisms. Interestingly, immunoglobulin G1 and G2 concentration and mass exhibited strong correlations suggesting that also some unknown mechanism of immunoglobulin G2 appearance in colostrum is occurring. Finally, no measured protein exhibited any correlation with the activity of lactate dehydrogenase in colostrum.

  18. Inhibition of energy-producing pathways of HepG2 cells by 3-bromopyruvate.

    Science.gov (United States)

    Pereira da Silva, Ana Paula; El-Bacha, Tatiana; Kyaw, Nattascha; dos Santos, Reinaldo Sousa; da-Silva, Wagner Seixas; Almeida, Fabio C L; Da Poian, Andrea T; Galina, Antonio

    2009-02-01

    3-BrPA (3-bromopyruvate) is an alkylating agent with anti-tumoral activity on hepatocellular carcinoma. This compound inhibits cellular ATP production owing to its action on glycolysis and oxidative phosphorylation; however, the specific metabolic steps and mechanisms of 3-BrPA action in human hepatocellular carcinomas, particularly its effects on mitochondrial energetics, are poorly understood. In the present study it was found that incubation of HepG2 cells with a low concentration of 3-BrPA for a short period (150 microM for 30 min) significantly affected both glycolysis and mitochondrial respiratory functions. The activity of mitochondrial hexokinase was not inhibited by 150 microM 3-BrPA, but this concentration caused more than 70% inhibition of GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and 3-phosphoglycerate kinase activities. Additionally, 3-BrPA treatment significantly impaired lactate production by HepG2 cells, even when glucose was withdrawn from the incubation medium. Oxygen consumption of HepG2 cells supported by either pyruvate/malate or succinate was inhibited when cells were pre-incubated with 3-BrPA in glucose-free medium. On the other hand, when cells were pre-incubated in glucose-supplemented medium, oxygen consumption was affected only when succinate was used as the oxidizable substrate. An increase in oligomycin-independent respiration was observed in HepG2 cells treated with 3-BrPA only when incubated in glucose-supplemented medium, indicating that 3-BrPA induces mitochondrial proton leakage as well as blocking the electron transport system. The activity of succinate dehydrogenase was inhibited by 70% by 3-BrPA treatment. These results suggest that the combined action of 3-BrPA on succinate dehydrogenase and on glycolysis, inhibiting steps downstream of the phosphorylation of glucose, play an important role in HepG2 cell death.

  19. Cytotoxic and antimigratory effects of Cratoxy formosum extract against HepG2 liver cancer cells.

    Science.gov (United States)

    Buranrat, Benjaporn; Mairuae, Nootchanat; Kanchanarach, Watchara

    2017-04-01

    The aim of the present study was to investigate the molecular mechanisms underlying Cratoxylum formosum (CF) Dyer-induced cancer cell death and antimigratory effects in HepG2 liver cancer cells. The cytotoxic, antiproliferative and antimigratory effects of CF leaf extract on human liver cancer HepG2 cell lines were evaluated using sulforhodamine B, colony formation, and wound healing assays. In addition, apoptosis induction mechanisms were investigated via reactive oxygen species (ROS) formation, caspase 3 activities, and mitochondrial membrane potential (ΔΨm) disruption. Gene expression and apoptosis-associated protein levels were measured by reverse transcription-quantitative polymerase chain reaction and western blotting. CF induced HepG2 cell death in a time- and dose-dependent manner with half maximal inhibitory concentration values of 219.03±9.96 and 124.90±6.86 µg/ml at 24 and 48 h, respectively. Treatment with CF caused a significant and dose-dependent decrease in colony forming ability and cell migration. Furthermore, the present study demonstrated that CF induced ROS formation, increased caspase 3 activities, decreased the ΔΨm, and caused HepG2 apoptosis. CF marginally decreased the expression level of the cell cycle regulatory protein, ras-related C3 botulinum toxin substrate 1 (rho family, small GTP binding protein Rac1) and the downstream protein, cyclin dependent kinase 6. Additionally, CF significantly enhanced p21 levels, reduced cyclin D1 protein levels and triggered cancer cell death. CF leaf extracts induced cell death, stimulated apoptosis and inhibited migration in HepG2 cells. Thus, CF may be useful for developing an anticancer drug candidate for the treatment of liver cancer.

  20. Long G2 accumulates recombination intermediates and disturbs chromosome segregation at dysfunction telomere in Schizosaccharomyces pombe

    Energy Technology Data Exchange (ETDEWEB)

    Habib, Ahmed G.K.; Masuda, Kenta; Yukawa, Masashi; Tsuchiya, Eiko [Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Ueno, Masaru, E-mail: scmueno@hiroshima-u.ac.jp [Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan); Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530 (Japan)

    2015-08-14

    Protection of telomere (Pot1) is a single-stranded telomere binding protein which is essential for chromosome ends protection. Fission yeast Rqh1 is a member of RecQ helicases family which has essential roles in the maintenance of genomic stability and regulation of homologous recombination. Double mutant between fission yeast pot1Δ and rqh1 helicase dead (rqh1-hd) maintains telomere by homologous recombination. In pot1Δ rqh1-hd double mutant, recombination intermediates accumulate near telomere which disturb chromosome segregation and make cells sensitive to microtubule inhibitors thiabendazole (TBZ). Deletion of chk1{sup +} or mutation of its kinase domain shortens the G2 of pot1Δ rqh1-hd double mutant and suppresses both the accumulation of recombination intermediates and the TBZ sensitivity of that double mutant. In this study, we asked whether the long G2 is the reason for the TBZ sensitivity of pot1Δ rqh1-hd double mutant. We found that shortening the G2 of pot1Δ rqh1-hd double mutant by additional mutations of wee1 and mik1 or gain of function mutation of Cdc2 suppresses both the accumulation of recombination intermediates and the TBZ sensitivity of pot1Δ rqh1-hd double mutant. Our results suggest that long G2 of pot1Δ rqh1-hd double mutant may allow time for the accumulation of recombination intermediates which disturb chromosome segregation and make cells sensitive to TBZ. - Ηighlights: • We show link between long G2 and accumulation of toxic recombination intermediates. • Accumulation of recombination intermediates at telomere results in TBZ sensitivity. • Activation of DNA damage checkpoint worsens cells' viability in presence of TBZ.

  1. Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ-irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose-response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r=0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

  2. Effect of shikonin on multidrug resistance in HepG2: The role of SIRT1.

    Science.gov (United States)

    Jin, Yong-Dong; Ren, Yi; Wu, Ming-Wei; Chen, Ping; Lu, Jin

    2015-07-01

    Overexpression of SIRT1 is considered to enhance the resistance of HepG2 cells to irradiation. Shikonin, a naturally occurring naphthoquinone compound, displays anticancer effects and circumvents cancer drug resistance. This study investigated the MDR reversal effect of shikonin induced by the overexpression of SIRT1. The overexpression of SIRT1 in HepG2 cells was established by lentivirus infection. Five days after transduction, real-time quantitative polymerase chain reaction and western blotting were used to detect the expression of SIRT1 and MDR1/P-gp. Drug resistance was also evaluated by flow cytometry after rhodamine-123 staining. On day 5, the multidrug resistance cells were treated by shikonin (10(-7), 10(-6), and 10(-5) µmol/L) one time. The cell viability was detected by the MTT assay, and apoptosis was evaluated by Hoechst 33342 staining and caspase-3 activity 24 h after shikonin treatment. Overexpression of SIRT1 decreased rhodamine-123 staining and successfully produced the R-HepG2 cell line. Compared with HepG2, the expression of MDR1/P-gp mRNA (3.45 ± 0.35) and protein (1.40 ± 0.05) were both upregulated in R-HepG2. Shikonin inhibited cell viability (from 93.9 ± 2.1 to 66.7 ± 1.5%), induced apoptosis of R-HepG2 (apoptotic ratio from 3.5 ± 0.8 to 47.5 ± 2.7%, caspase-3 activity from 103.5 ± 1.9 to 329.2 ± 14.9%, respectively), downregulated the mRNA and protein expression of SIRT1 and MDR1/P-gp, and decreased rhodamin 123 efflux. In the present study, we demonstrated that shikonin is able to overcome drug resistance in hepatocellular carcinoma cells, and the mechanism is related to the SIRT1-MDR1/P-gp signaling pathway.

  3. 26 CFR 31.3406(g)-2 - Exception for reportable payment for which withholding is otherwise required.

    Science.gov (United States)

    2010-04-01

    ... withholding is otherwise required. 31.3406(g)-2 Section 31.3406(g)-2 Internal Revenue INTERNAL REVENUE SERVICE... TAXES AND COLLECTION OF INCOME TAX AT SOURCE Collection of Income Tax at Source § 31.3406(g)-2 Exception... wages (as defined in section 3401) because, e.g., the employee makes a certification under section...

  4. Evolution equation for the structure function g_2(x,Q^2)

    CERN Document Server

    Braun, V M; Manashov, A N

    2001-01-01

    We perform an extensive study of the scale dependence of flavor-singlet contributions to the structure function g_2(x,Q^2) in polarized deep-inelastic scattering. We find that the mixing between quark-antiquark-gluon and three-gluon twist-3 operators only involves the three-gluon operator with the lowest anomalous dimension and is weak in other cases. This means, effectively, that only those three-gluon operators with the lowest anomalous dimension for each moment are important, and allows to formulate a simple two-component parton-like description of g_2(x,Q^2) in analogy with the conventional description of twist-2 parton distributions. The similar simplification was observed earlier for the nonsinglet distributions, although the reason is in our case different.

  5. Kinetics of aflatoxin B1 and G2 adsorption on Ca-clinoptilolite

    Directory of Open Access Journals (Sweden)

    VERA DONDUR

    2000-10-01

    Full Text Available The kinetics of aflatoxins B1 and G2 adsorption on Ca-clinoptilolite at pH 2 and 7, in aqueous electrolyte at 37°C were studied. For both aflatoxins, the adsorption process begins with a fast reaction whereby most of the toxin is adsorbed in the first few minutes. This fast process is followed by the significantly slower process of aflatoxin bonding at active centers of mineral adsorbent. The initial rate method showed that the fast adsorption process of aflatoxin B1 and G2, at both pH values is a first order reaction, while the slow adsorption process of these aflatoxins is a zero order reaction. The adsorption indexes and adsorption rates for both examined toxins were pH dependent. In the investigated initial toxins concentration ranges (500–3000 µg/dm3, high adsorption indexes were achieved (> 80 %.

  6. Weyl Modules for Groups of Type B(2) and G(2)

    Science.gov (United States)

    Fitzgerald, John G. M.

    Available from UMI in association with The British Library. Requires signed TDF. In this thesis we determine the submodule structure of a number of Weyl modules for algebraic groups with root systems B_2 and G_2 . We use the Jantzen sum formula to find the composition factors of Weyl modules and go on to use homomorphisms between Weyl modules, given by H. H. Andersen, and the comparison of two filtrations of tensor products of Weyl modules to establish submodule structure. A computer program in the Prolog language is given which calculates the Jantzen sum formula. In addition we find one 2-dimensional Ext group for simple modules for type G_2 in characteristic greater than or equal to 7.

  7. Development and testing of fiber beam monitors for the Muon g-2 experiment

    Science.gov (United States)

    Bjorkquist, Robin; Diamond, Edward; Martinez, Benjamin; Sblendorio, Alec; Gray, Frederick; Muon g-2 Collaboration

    2017-01-01

    The Muon g-2 experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion. Careful characterization of the stored muon beam will be crucial for the experiment, because several beam-related systematic effects must be taken into account. The fiber beam monitors will provide a direct measurement of the spatial, temporal and momentum distributions and betatron oscillations of the stored muon beam. These detectors were originally built by KEK for the previous Muon g-2 experiment at Brookhaven National Lab, but have been repaired and refurbished for the upcoming experiment, including new scintillating fibers and upgraded SiPM-based readout electronics. We present the final design of the fiber beam monitor system and the results of a recent beam test performed at SLAC.

  8. Enhanced diphoton signal of the Higgs boson and the muon g-2 in gauge mediation models

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Ryosuke; Tobioka, Kohsaku [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa 277-8583 (Japan); Yokozaki, Norimi, E-mail: yokozaki@hep-th.phys.s.u-tokyo.ac.jp [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, Kashiwa 277-8583 (Japan)

    2012-10-02

    We study the diphoton signal of the Higgs boson in gauge mediated supersymmetry breaking models, which can explain both the Higgs boson mass of around 125 GeV and the result of the muon g-2 experiment. We consider two possible extensions of gauge mediation models: inclusion of vector-like matters, and a mixing between a messenger and the up-type Higgs. The large left-right mixing of staus is induced in both scenarios, resulting in the enhanced diphoton signal. We include a constraint from a charge breaking minimum, which is severe for the large left-right mixing of staus. The branching fraction of h{yields}{gamma}{gamma} can be about 20-30% larger than that of the Standard Model Higgs boson, in the region of parameter space where the Higgs boson mass of around 125 GeV and the muon g-2 are explained.

  9. Closing the Door for Dark Photons as the Explanation for the Muon g-2 Anomaly

    CERN Document Server

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Akimoto, R; Al-Bataineh, H; Al-Ta'ani, H; Alexander, J; Alfred, M; Andrews, K R; Angerami, A; Aoki, K; Apadula, N; Aphecetche, L; Appelt, E; Aramaki, Y; Armendariz, R; Asai, J; Asano, H; Aschenauer, E C; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Baldisseri, A; Bandara, N S; Bannier, B; Barish, K N; Barnes, P D; Bassalleck, B; Basye, A T; Bathe, S; Batsouli, S; Baublis, V; Baumann, C; Bazilevsky, A; Beaumier, M; Beckman, S; Belikov, S; Belmont, R; Ben-Benjamin, J; Bennett, R; Berdnikov, A; Berdnikov, Y; Bhom, J H; Bickley, A A; Black, D; Blau, D S; Boissevain, J G; Bok, J; Bok, J S; Borel, H; Boyle, K; Brooks, M L; Broxmeyer, D; Bryslawskyj, J; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Caringi, A; Castera, P; Chang, B S; Chang, W C; Charvet, J -L; Chen, C -H; Chernichenko, S; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Churyn, A; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; del Valle, Z Conesa; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; Daugherity, M S; David, G; Dayananda, M K; DeBlasio, K; Dehmelt, K; Denisov, A; d'Enterria, D; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Ding, L; Dion, A; Do, J H; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Dubey, A K; Durham, J M; Durum, A; Dutta, D; Dzhordzhadze, V; D'Orazio, L; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Eyser, K O; Fadem, B; Feege, N; Fields, D E; Finger, M; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Gal, C; Gallus, P; Garg, P; Garishvili, I; Ge, H; Giordano, F; Glenn, A; Gong, H; Gong, X; Gonin, M; Gosset, J; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Grim, G; Perdekamp, M Grosse; Gu, Y; Gunji, T; Guo, L; Guragain, H; Gustafsson, H -Å; Hachiya, T; Henni, A Hadj; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Han, S Y; Hanks, J; Harper, C; Hartouni, E P; Haruna, K; Hasegawa, S; Hashimoto, K; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Hollis, R S; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hori, Y; Hornback, D; Hoshino, T; Huang, J; Huang, S; Ichihara, T; Ichimiya, R; Iinuma, H; Ikeda, Y; Imai, K; Imazu, Y; Imrek, J; Inaba, M; Iordanova, A; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Ivanishchev, D; Iwanaga, Y; Jacak, B V; Jeon, S J; Jezghani, M; Jia, J; Jiang, X; Jin, J; John, D; Johnson, B M; Jones, T; Joo, E; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kaneti, S; Kang, B H; Kang, J H; Kang, J S; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Key, J A; Khachatryan, V; Khanzadeev, A; Kihara, K; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, C; Kim, D H; Kim, D J; Kim, E; Kim, E -J; Kim, H -J; Kim, M; Kim, S H; Kim, Y -J; Kim, Y K; Kinney, E; Kiriluk, K; Kiss, Á; Kistenev, E; Klatsky, J; Klay, J; Klein-Boesing, C; Kleinjan, D; Kline, P; Koblesky, T; Kochenda, L; Kofarago, M; Komkov, B; Konno, M; Koster, J; Kotov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Layton, D; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K S; Lee, S H; Lee, S R; Lee, T; Leitch, M J; Leite, M A L; Leitgab, M; Lenzi, B; Li, X; Lichtenwalner, P; Liebing, P; Lim, S H; Levy, L A Linden; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Makek, M; Malakhov, A; Malik, M D; Manion, A; Manko, V I; Mannel, E; Mao, Y; Mašek, L; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Means, N; Meles, A; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Mikeš, P; Miki, K; Miller, A J; Milov, A; Mishra, D K; Mishra, M; Mitchell, J T; Miyachi, Y; Miyasaka, S; Mizuno, S; Mohanty, A K; Montuenga, P; Moon, H J; Moon, T; Morino, Y; Morreale, A; Morrison, D P; Motschwiller, S; Moukhanova, T V; Mukhopadhyay, D; Murakami, T; Murata, J; Mwai, A; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakagomi, H; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Nattrass, C; Netrakanti, P K; Newby, J; Nguyen, M; Nihashi, M; Niida, T; Nouicer, R; Novitzky, N; Nyanin, A S; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Koop, J D Orjuela; Oskarsson, A; Ouchida, M; Ozaki, H; Ozawa, K; Pak, R; Palounek, A P T; Pantuev, V; Papavassiliou, V; Park, B H; Park, I H; Park, J; Park, S; Park, S K; Park, W J; Pate, S F; Patel, L; Patel, M; Pei, H; Peng, J -C; Pereira, H; Perepelitsa, D V; Perera, G D N; Peresedov, V; Peressounko, D Yu; Perry, J; Petti, R; Pinkenburg, C

    2014-01-01

    The standard model (SM) of particle physics is spectacularly successful, yet the measured value of the muon anomalous magnetic moment (g-2)_\\mu deviates from SM calculations by 3.6 sigma. Several theoretical models attribute this to the existence of a "dark photon", an additional U(1) gauge boson, which is weakly coupled to ordinary photons. The PHENIX experiment at the Relativistic Heavy Ion Collider has searched for a dark photon, U, in \\pi^0,\\eta \\rightarrow \\gamma e^+e^- decays and obtained upper limits on U-\\gamma mixing at 90% CL for the mass range 30 < m_U < 90 MeV/c^2. Combined with other experimental limits, the remaining region in the U-\\gamma mixing parameter space that can explain the (g-2)_\\mu deviation from its SM value is nearly completely excluded at the 90% confidence level, with only a small region of 30 < m_U < 36 MeV/c^2 remaining.

  10. IgG2 immunodeficiency: association to pediatric patients with bacterial meningoencephalitis

    Directory of Open Access Journals (Sweden)

    ESCOBAR-PÉREZ XIOMARA

    2000-01-01

    Full Text Available An IgG subclass deficiency is often associated with bacterial infections. We studied four pediatric patients suffering from meningoencephalitis, two of them due to Streptococcus pneumoniae and two due to Haemophilus influenzae type b. Simultaneous diagnostic serum and cerebrospinal fluid samples were taken during income. The four subclasses of IgG and albumin were quantified in both biologic fluids by radial immunodiffusion. Very low levels of seric IgG2 with non detectable cerebrospinal fluid IgG2 were found in the patients. No intrathecal IgG subclass synthesis was found in two patients. One patient with S. pneumoniae had IgG3 intrathecal synthesis. Intrathecal IgG1, IgG3 and IgG4 synthesis was found in one patient suffering from H. influenzae according with reibergrams. Substitutive therapy with intravenous gammaglobulin was given to the patients as part of the treatment.

  11. Measuring the leading hadronic contribution to the muon g-2 via μ e scattering

    Science.gov (United States)

    Abbiendi, G.; Calame, C. M. Carloni; Marconi, U.; Matteuzzi, C.; Montagna, G.; Nicrosini, O.; Passera, M.; Piccinini, F.; Tenchini, R.; Trentadue, L.; Venanzoni, G.

    2017-03-01

    We propose a new experiment to measure the running of the electromagnetic coupling constant in the space-like region by scattering high-energy muons on atomic electrons of a low- Z target through the elastic process μ e → μ e. The differential cross section of this process, measured as a function of the squared momentum transfer t=q^2Area, a statistical uncertainty of ˜ 0.3% can be achieved on a^{HLO}_{μ } after two years of data taking. The direct measurement of a^{HLO}_{μ } via μ e scattering will provide an independent determination, competitive with the time-like dispersive approach, and consolidate the theoretical prediction for the muon g-2 in the Standard Model. It will allow therefore a firmer interpretation of the measurements of the future muon g-2 experiments at Fermilab and J-PARC.

  12. Biosynthesis of hematite nanoparticles and its cytotoxic effect on HepG2 cancer cells.

    Science.gov (United States)

    Rajendran, Kumar; Karunagaran, Vithiya; Mahanty, Biswanath; Sen, Shampa

    2015-03-01

    Iron oxide nanoparticles were gaining significant importance in a variety of applications due to its paramagnetic properties and biocompatibility. Various chemical methods were employed for hematite nanoparticle synthesis which require special equipment or a complex production process. In this study, protein capped crystalline hexagonal hematite (α-Fe2O3) nanoparticles were synthesized by green approach using culture supernatant of a newly isolated bacterium, Bacillus cereus SVK1 at ambient conditions. The synthesized nanoparticles were characterized by electron microscopy, X-ray diffraction, UV-visible spectroscopy and Fourier transform infrared spectroscopic analysis. Nanoparticles were evaluated for its possible anticancer activity against HepG2 liver cancer cells by MTT assay. Hematite nanoparticles with an average diameter of 30.2 nm, exhibited a significant cytotoxicity toward HepG2 cells in a concentration-dependent manner (CTC50=704 ng/ml). Copyright © 2014 Elsevier B.V. All rights reserved.

  13. The MAP, M/G1,G2/1 queue with preemptive priority

    Directory of Open Access Journals (Sweden)

    Bong Dae Choi

    1997-01-01

    Full Text Available We consider the MAP, M/G1,G2/1 queue with preemptive resume priority, where low priority customers arrive to the system according to a Markovian arrival process (MAP and high priority customers according to a Poisson process. The service time density function of low (respectively: high priority customers is g1(x (respectively: g2(x. We use the supplementary variable method with Extended Laplace Transforms to obtain the joint transform of the number of customers in each priority queue, as well as the remaining service time for the customer in service in the steady state. We also derive the probability generating function for the number of customers of low (respectively, high priority in the system just after the service completion epochs for customers of low (respectively, high priority.

  14. Optimization of the Target Subsystem for the New g-2 Experiment

    CERN Document Server

    Yoshikawa, C; Mokhov, N V; Morgan, J; Neuffer, D; Striganov, S

    2013-01-01

    A precision measurement of the muon anomalous magnetic moment, $a_{\\mu} = (g-2)/2$, was previously performed at BNL with a result of 2.2 - 2.7 standard deviations above the Standard Model (SM) theoretical calculations. The same experimental apparatus is being planned to run in the new Muon Campus at Fermilab, where the muon beam is expected to have less pion contamination and the extended dataset may provide a possible $7.5\\sigma$ deviation from the SM, creating a sensitive and complementary bench mark for proposed SM extensions. We report here on a preliminary study of the target subsystem where the apparatus is optimized for pions that have favorable phase space to create polarized daughter muons around the magic momentum of 3.094 GeV/c, which is needed by the downstream g 2 muon ring.

  15. Transition zone cells reach G2 phase before initiating elongation in maize root apex

    Directory of Open Access Journals (Sweden)

    M. Victoria Alarcón

    2017-06-01

    Full Text Available Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop division and rapidly elongate. Throughout this journey cells are accompanied by changes in cell cycle progression. Flow cytometry analysis showed that meristematic cells are in cycle, but exit when they enter the elongation zone. In addition, the percentage of cells in G2 phase (4C strongly increased from the meristem to the elongation zone. However, we did not observe remarkable changes in the percentage of cells in cell cycle phases along the entire elongation zone. These results suggest that meristematic cells in maize root apex stop the cell cycle in G2 phase after leaving the meristem.

  16. Reconciling Muon g-2, 125 GeV Higgs and Dark Matter in Gauge Mediation Models

    CERN Document Server

    Gogoladze, Ilia; Un, Cem Salih

    2015-01-01

    We present a class of models in the framework of gauge mediation supersymmetry breaking where the standard model is supplemented by additional U(1) symmetry which acts only on the third generation fermions. The messenger fields carry non-trivial U(1) charge and are vector-like particles under this symmetry. This leads to additional contribution to the soft supersymmetry breaking mass terms for the third generation squarks and sleptons. In this framework we show that the muon g-2 anomaly, the observed 125 GeV Higgs boson mass and the detected relic dark matter abundance (gravitino in our case) can be simultaneously accommodated. The resolution of the muon g-2 anomaly, in particular, yields the result that the first two generation squark masses, as well the gluino mass, should be <~ 2.5 TeV, which will be tested at LHC14.

  17. Unique features of monoclonal IgG2b in the cleavage reaction with pepsin.

    Directory of Open Access Journals (Sweden)

    Sumii,Hiroshi

    1989-06-01

    Full Text Available Preparations of IgG2b purified from several mouse hybridoma clones were highly susceptible, compared to other subclasses, to peptic digestion under conditions usually used to prepare F (ab'2 fragments. Analyses of the digestion products revealed that no F (ab'2 was produced and that the main product was a Fab-like fragment. Demonstration of the hinge disulfides in the Fc portion clearly indicated that in IgG2b the primary peptic cleavage occurs on the NH2-terminal side of the inter-heavy chain disulfide bridge. The resulting Fab failed to bind with antigen, suggesting the importance of the CH1-hinge region in maintaining the native conformation of the antigen-binding site.

  18. Recognition of the group G2(5 by the prime graph

    Directory of Open Access Journals (Sweden)

    Parivash Nosratpour

    2014-05-01

    Full Text Available Let $G$ be a finite group‎. ‎The prime graph of $G$‎ ‎is a graph $\\Gamma(G$ with vertex set $\\pi(G$‎, ‎the set of all‎ ‎prime divisors of $|G|$‎, ‎and two distinct vertices $p$ and $q$ are‎ ‎adjacent by an edge if $G$ has an element of order $pq$‎. ‎In this‎ ‎paper we prove that if $\\Gamma(G=\\Gamma(G_2(5$‎, ‎then $G$ has a‎ ‎normal subgroup $N$ such that $\\pi(N\\subseteq\\{2,3,5\\}$ and‎ ‎$G/N\\cong G_2(5$‎.

  19. [Study on transient absorption spectrum of tungsten nanoparticle with HepG2 tumor cell].

    Science.gov (United States)

    Cao, Lin; Shu, Xiao-Ning; Liang, Dong; Wang, Cong

    2014-07-01

    Significance of this study lies in tungsten nano materials can be used as a preliminary innovative medicines applied basic research. This paper investigated the inhibition of tungsten nanoparticles which effected on human hepatoma HepG2 cells by MTT. The authors use transient absorption spectroscopy (TAS) technology absorption and emission spectra characterization of charge transfer between nanoparticles and tumor cell. The authors discussed the role of the tungsten nanoparticles in the tumor early detection of the disease and its anti-tumor properties. In the HepG2 experiments system, 100-150 microg x mL(-1) is the best drug concentration of anti-tumor activity which recact violently within 6 hours and basically completed in 24 hours. The results showed that transient absorption spectroscopy can be used as tumor detection methods and characterization of charge transfer between nano-biosensors and tumor cells. Tungsten nanoparticles have potential applications as anticancer drugs.

  20. Estradiol and Estrogen Receptor Agonists Oppose Oncogenic Actions of Leptin in HepG2 Cells.

    Directory of Open Access Journals (Sweden)

    Minqian Shen

    Full Text Available Obesity is a significant risk factor for certain cancers, including hepatocellular carcinoma (HCC. Leptin, a hormone secreted by white adipose tissue, precipitates HCC development. Epidemiology data show that men have a much higher incidence of HCC than women, suggesting that estrogens and its receptors may inhibit HCC development and progression. Whether estrogens antagonize oncogenic action of leptin is uncertain. To investigate potential inhibitory effects of estrogens on leptin-induced HCC development, HCC cell line HepG2 cells were treated with leptin in combination with 17 β-estradiol (E2, estrogen receptor-α (ER-α selective agonist PPT, ER-β selective agonist DPN, or G protein-coupled ER (GPER selective agonist G-1. Cell number, proliferation, and apoptosis were determined, and leptin- and estrogen-related intracellular signaling pathways were analyzed. HepG2 cells expressed a low level of ER-β mRNA, and leptin treatment increased ER-β expression. E2 suppressed leptin-induced HepG2 cell proliferation and promoted cell apoptosis in a dose-dependent manner. Additionally E2 reversed leptin-induced STAT3 and leptin-suppressed SOCS3, which was mainly achieved by activation of ER-β. E2 also enhanced ERK via activating ER-α and GPER and activated p38/MAPK via activating ER-β. To conclude, E2 and its receptors antagonize the oncogenic actions of leptin in HepG2 cells by inhibiting cell proliferation and stimulating cell apoptosis, which was associated with reversing leptin-induced changes in SOCS3/STAT3 and increasing p38/MAPK by activating ER-β, and increasing ERK by activating ER-α and GPER. Identifying roles of different estrogen receptors would provide comprehensive understanding of estrogenic mechanisms in HCC development and shed light on potential treatment for HCC patients.

  1. A new measurement of the leading hadronic corrections to the muon g-2

    Science.gov (United States)

    Trentadue, Luca

    2016-11-01

    A novel approach to determine the leading hadronic corrections to the muon g-2 is proposed. It consists in a measurement of the effective electromagnetic coupling in the space-like region. This method may become feasible at flavor factories resulting in a determination potentially competitive with the dispersive approach via time-like data. This talk is based on a work done in collaboration with C. Carloni Calame, M. Passera, and G. Venanzoni.

  2. Test of candidate light distributors for the muon (g$-$2) laser calibration system

    CERN Document Server

    Anastasi, A; Baffigi, F; Cantatore, G; Cauz, D; Corradi, G; Dabagov, S; Di Sciascio, G; Di Stefano, R; Ferrari, C; Fienberg, A T; Fioretti, A; Fulgentini, L; Gabbanini, C; Gizzi, L A; Hampai, D; Hertzog, D W; Iacovacci, M; Karuza, M; Kaspar, J; Koester, P; Labate, L; Mastroianni, S; Moricciani, D; Pauletta, G; Santi, L; Venanzoni, G

    2015-01-01

    The new muon (g-2) experiment E989 at Fermilab will be equipped with a laser calibration system for all the 1296 channels of the calorimeters. An integrating sphere and an alternative system based on an engineered diffuser have been considered as possible light distributors for the experiment. We present here a detailed comparison of the two based on temporal response, spatial uniformity, transmittance and time stability.

  3. Normal Subgroup Growth of Linear Groups: the (G2; F4;E8)-Theorem

    CERN Document Server

    Larsen, Michael

    2011-01-01

    Let G be a finitely generated group and M_n(G) the number of its normal subgroup subgroups of index at most n. For linear groups G we show that M_n(G) can grow polynomially in n only if the semisimple part of the Zariski closure of G has simple components only of type G2, F4 or E8 (and in this case indeed this can happened!)

  4. Induction of apoptosis in HepG2 cells by solanine and Bcl-2 protein.

    Science.gov (United States)

    Ji, Y B; Gao, S Y; Ji, C F; Zou, X

    2008-01-17

    The nightshade (Solanum nigrum Linn.) has been widely used in Chinese traditional medicine as a remedy for the treatment of digestive system cancer. The anti-tumor activity of solanine, a steroid alkaloid isolated from the nightshade has been demonstrated. To observe the effect of anti-tumor and mechanism of solanine. The MTT assay was used to evaluate the IC(50) on the three digestive system tumor cell lines. The effect on the morphology was observed with a laser confocal microscopy; the rate of apoptosis and the cell cycle were measured using flow cytometry (FCM); the expression of Bcl-2 protein was measured by Western blot. The results show that the IC(50) for HepG(2), SGC-7901, and LS-174 were 14.47, >50, and >50 microg/ml, respectively; the morphology of cells in the negative control was normal; for the treated groups, typical signs for apoptosis were found. The rate of apoptosis in HepG(2) cells induced by solanine was found to be 6.0, 14.4, 17.3, 18.9, and 32.2%, respectively. Observation of the cell cycle showed that cells in the G(2)/M phases disappeared while the number of cells in the S phase increased significantly for treated groups. Western blot showed that solanine decreased the expression of Bcl-2 protein. Therefore, the target of solanine in inducing apoptosis in HepG(2) cells seems to be mediated by the inhibition in the expression of Bcl-2 protein.

  5. Gene Transfection Mediated by Ultrasound and Pluronic P85 in HepG2 Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Fen; LI Kaiyan; CHEN Yunchao; DENG Yuan; HONG Kai

    2007-01-01

    In order to assess whether gene transfection could be mediated by ultrasound in associa- tion with P85 and find the appropriate parameters of ultrasound irradiation, the effects of ultrasound with or without P85 on gene transfection of HepG2 cells were examined. The HepG2 cells were irra- diated by ultrasound at 1 MHz, 0.4-2.0 W/cm2 and 50% duty cycle with plasmid encoding enhanced green fluorescent protein (EGFP) as a report gene. Forty-eight h later, the expression of EGFP was detected under the fluorescence microscopy. Transfection efficacy was quantitatively assessed by flow cytometry, and cell viability was evaluated by trypan blue exclusion. The results showed that the transfection efficacy was increased with the increases in ultrasound output power and the ideal trans- fection efficacy was achieved in HepG2 cells irradiated by ultrasound at 0.8 W/cm2 for 30 s. The transfection efficacy in ulstrasound+P85 group was three times higher than in single ultrasound group [(17.63±1.07)% vs (5.57±0.56)%, P<0.051. The cell viability was about 81% and 62% in ultrasound group and ultrasound+P85 group respectively. It was concluded that ultrasound in combination with P85 could mediate the gene transfection of HepG2 cells, ideal transfection efficacy was achieved by ultrasound irradiation at 0.8 W/cm2 for 30 s, and P85 could somewhat increase the damage to cells caused by ultrasound.

  6. A new approach to evaluate the leading hadronic corrections to the muon g-2

    Directory of Open Access Journals (Sweden)

    C.M. Carloni Calame

    2015-06-01

    Full Text Available We propose a novel approach to determine the leading hadronic corrections to the muon g-2. It consists in a measurement of the effective electromagnetic coupling in the space-like region extracted from Bhabha scattering data. We argue that this new method may become feasible at flavor factories, resulting in an alternative determination potentially competitive with the accuracy of the present results obtained with the dispersive approach via time-like data.

  7. ZGDHu-1 induces G2/M phase arrest and apoptosis in Kasumi-1 cells

    Science.gov (United States)

    XIA, JUN; CHEN, SU-FENG; LV, YA-PING; LU, LING-NA; HU, WEI-XIAO; ZHOU, YONG-LIE

    2015-01-01

    The present study examined the effects of N,N′-di-(m-methylphenyi)-3, 6-dimethyl-1, 4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamide (ZGDHu-1), a novel oxazine derivative, in Kasumi-1 cells. Following incubation with various concentrations of ZGDHu-1, fluorescence-activated cell sorting (FACS) was used in order to detect changes in mitochondrial membrane permeability in Kasumi-1 cells. Western blot analysis was performed in order to analyze the expression of nuclear factor-κB, inhibitor of κB and AML1/ETO. In addition FACS was used to analyze leukemia cell cycles and the expression levels of cyclin, cyclin-dependent kinases and cyclin-dependent kinase inhibitors in G2/M phase were determined using FACS and western blot analysis. The upregulation of reactive oxygen species production and mitochondrial membrane permeability was ascribed to apoptosis. The growth of Kasumi-1 cells was inhibited through the downregulation of nuclear factor-κB, degradation of AML1/ETO fusion protein and cell cycle arrest at the G2/M phase. This study documented that G2/M regulatory molecules, including cyclin B1, cell division control (cdc)2 and cdc25c were downregulated and checkpoint kinase 1 (CHK1), p53, p27, phospho-cdc25c, phospho-CHK1 and phospho-p53 were upregulated following treatment with ZGDHu-1. In the present study, pretreatment with CHIR-124, a selective CHK1 inhibitor, abrogated G2/M arrest via ZGDHu-1. These results demonstrated the anti-tumor activity of ZGDHu-1, which may therefore a potential target for further investigation and may be useful for the treatment of patients with t(8;21) acute myeloid leukemia. PMID:25573277

  8. Efficacy of HIV antiviral polyanionic carbosilane dendrimer G2-S16 in the presence of semen

    Directory of Open Access Journals (Sweden)

    Ceña-Diez R

    2016-05-01

    Full Text Available Rafael Ceña-Diez,1–4,* Pilar García-Broncano,1–5,* Francisco Javier de la Mata,4,6 Rafael Gómez,4,6 Mª Ángeles Muñoz-Fernández1–4 1Hospital General Universitario Gregorio Marañon, 2Instituto de Investigación Sanitaria Gregorio Marañon, 3Spanish HIV HGM Biobank, 4Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN, 5Laboratory of Viral Infection and Immunity, National Center of Microbiology, Health Institute of Carlos III, Majadahonda, 6Department of Organic Chemistry and Inorganic Chemistry, University of Alcalá, Alcalá de Henares, Madrid, Spain *These authors contributed equally to this work Abstract: The development of a safe and effective microbicide to prevent the sexual transmission of human immunodeficiency virus (HIV-1 is urgently needed. Unfortunately, the majority of microbicides, such as poly(L-lysine-dendrimers, anionic polymers, or antiretrovirals, have proved inactive or even increased the risk of HIV infection in clinical trials, most probably due to the fact that these compounds failed to prevent semen-exposed HIV infection. We showed that G2-S16 dendrimer exerts anti-HIV-1 activity at an early stage of viral replication, blocking the gp120/CD4/CCR5 interaction and providing a barrier to infection for long periods, confirming its multifactorial and nonspecific ability. Previously, we demonstrated that topical administration of G2-S16 prevents HIV transmission in humanized BLT mice without irritation or vaginal lesions. Here, we demonstrated that G2-S16 is active against mock- and semen-exposed HIV-1 and could be a promising microbicide against HIV infection. Keywords: G2-S16, dendrimer, HIV-1, SEVI, microbicide, antiretrovirals

  9. ECCO Golf BIOM G2健步高尔夫2代系列

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    北欧丹麦鞋履及皮具品牌ECC0推出全新ECCO Golf BIOM G2健步高尔夫2代系列,分别为男士和女士精心打造.采用专利NATURAL MOTION自然律动技术,提供出色的缓震性与稳定性.

  10. Cacao polyphenols influence the regulation of apolipoprotein in HepG2 and Caco2 cells.

    Science.gov (United States)

    Yasuda, Akiko; Natsume, Midori; Osakabe, Naomi; Kawahata, Keiko; Koga, Jinichiro

    2011-02-23

    Cocoa powder is rich in polyphenols, such as catechins and procyanidins, and has been shown to inhibit low-density lipoprotein (LDL) oxidation and atherogenesis in a variety of models. Human studies have also shown daily intake of cocoa increases plasma high-density lipoprotein (HDL) and decreases LDL levels. However, the mechanisms responsible for these effects of cocoa on cholesterol metabolism have yet to be fully elucidated. The present study investigated the effects of cacao polyphenols on the production of apolipoproteins A1 and B in human hepatoma HepG2 and intestinal Caco2 cell lines. The cultured HepG2 cells or Caco2 cells were incubated for 24 h in the presence of cacao polyphenols such as (-)-epicatechin, (+)-catechin, procyanidin B2, procyanidin C1, and cinnamtannin A2. The concentration of apolipoproteins in the cell culture media was quantified using an enzyme-linked immunoassay, and the mRNA expression was quantified by RT-PCR. Cacao polyphenols increased apolipoprotein A1 protein levels and mRNA expression, even though apolipoprotein B protein and the mRNA expression were slightly decreased in both HepG2 cells and Caco2 cells. In addition, cacao polyphenols increased sterol regulatory element binding proteins (SREBPs) and activated LDL receptors in HepG2 cells. These results suggest that cacao polyphenols may increase the production of mature form SREBPs and LDL receptor activity, thereby increasing ApoA1 and decreasing ApoB levels. These results elucidate a novel mechanism by which HDL cholesterol levels become elevated with daily cocoa intake.

  11. The reach of a future Linear Collider after the g-2 result

    CERN Document Server

    Richard, F

    2001-01-01

    Combining the cosmological requirement on dark matter with the recent BNL g-2 measurement it is argued that, within the mSUGRA framework, the preferred region for SUSY mass parameters falls well inside the area covered by the future linear colliders under consideration for right handed sleptons and of the 2 lightest neutralinos. The coverage for the lightest chargino and left handed sleptons is also favoured but with smaller confidence.

  12. Rotavirus G2P[4] detection in fresh vegetables and oysters in Mexico City.

    Science.gov (United States)

    Quiroz-Santiago, Carolina; Vázquez-Salinas, Carlos; Natividad-Bonifacio, Ivan; Barrón-Romero, Blanca Lilia; Quiñones-Ramírez, Elsa Irma

    2014-11-01

    Rotaviruses are the principal cause of dehydration caused by diarrhea in children younger than 2 years of age. Although these viral infections have mainly been associated with ingestion of fecally contaminated food and water, few studies have addressed the presence of the virus in food that is consumed raw or slightly cooked. In this work, 30 oyster samples and 33 vegetable samples were examined for the presence of rotavirus genotypes to evaluate their potential to produce gastrointestinal infections. The rotaviruses were identified by reverse transcriptase PCR amplification of the VP7 gene. G and P genotyping was also performed by reverse transcriptase PCR, with a detection sensitivity of up to 15 PFU/ml. Rotaviruses were found in 17 (26.9%) of 63 samples (10 oysters and 7 vegetables). The G2 genotype was found in 11 (64.7%) of 17 of the rotavirus strains, and 16 (94.1%) of 17 had the P[4] genotype. The combined genotypes found most frequently were G2P[4] (10 [58.82%] of 17), GNTP[4] (6 [35.29%] of 17), and G2P[NT] (1 [5.8%] of 17).

  13. No asymmetric outflows from Sagittarius A* during the pericenter passage of the gas cloud G2

    CERN Document Server

    Park, J -H; Krichbaum, T P; Kim, J -Y; Kino, M; Bertarini, A; Bremer, M; de Vicente, P

    2015-01-01

    The gas cloud G2 falling toward Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, is supposed to provide valuable information on the physics of accretion flows and the environment of the black hole. We observed Sgr A* with four European stations of the Global Millimeter Very Long Baseline Interferometry Array (GMVA) at 86 GHz on 1 October 2013 when parts of G2 had already passed the pericenter. We searched for possible transient asymmetric structure -- such as jets or winds from hot accretion flows -- around Sgr A* caused by accretion of material from G2. The interferometric closure phases remained zero within errors during the observation time. We thus conclude that Sgr A* did not show significant asymmetric (in the observer frame) outflows in late 2013. Using simulations, we constrain the size of the outflows that we could have missed to ~2.5 mas along the major axis, ~0.4 mas along the minor axis of the beam, corresponding to approximately 232 and 35 Schwarzschild radii, ...

  14. NPM phosphorylation stimulates Cdk1, overrides G2/M checkpoint and increases leukemic blasts in mice.

    Science.gov (United States)

    Du, Wei; Zhou, Yun; Pike, Suzette; Pang, Qishen

    2010-02-01

    An elevated level of nucleophosmin (NPM) is often found in actively proliferative cells including human tumors. To identify the regulatory role for NPM phosphorylation in proliferation and cell cycle control, a series of mutants targeting the consensus cyclin-dependent kinase (CDK) phosphorylation sites was created to mimic or abrogate either single-site or multi-site phosphorylation. Simultaneous inactivation of two CDK phosphorylation sites at Ser10 and Ser70 (NPM-AA) induced G(2)/M cell cycle arrest, phosphorylation of Cdk1 at Tyr15 (Cdc2(Tyr15)) and increased cytoplasmic accumulation of Cdc25C. Strikingly, stress-induced Cdk1(Tyr15) and Cdc25C sequestration was suppressed by expression of a phosphomimetic NPM mutant created on the same CDK sites (S10E/S70E, NPM-EE). Further analysis revealed that phosphorylation of NPM at both Ser10 and Ser70 was required for proper interaction between Cdk1 and Cdc25C. Moreover, NPM-EE directly bound to Cdc25C and prevented phosphorylation of Cdc25C at Ser216 during mitosis. Finally, NPM-EE overrided stress-induced G(2)/M arrest and increased leukemia blasts in a NOD/SCID xenograft model. Thus, these findings reveal a novel function of NPM on regulation of cell cycle progression, in which phosphorylation of NPM controls cell cycle progression at G(2)/M transition through modulation of Cdk1 and Cdc25C activities.

  15. SUMO-1 Enhancing the p53-induced HepG2 Cell Apoptosis

    Institute of Scientific and Technical Information of China (English)

    LU Xingrong; YI Jilin

    2005-01-01

    Summary: In order to investigate the effect of small ubiquitin-like modifier-1 (SUMO-1) on the p53-induced HepG2 cell apoptosis, HepG2 cells were transfected by recombinant plasmids as pwtp53, pMDM2 and pSUMO-1 respectively. Western blot was employed to detect the protein expression of the transfected recombinant plasmids and the rate of apoptosis was measured by flow cytometry. The results showed that in cells transfected with pwtp53 and pwtp53+pSUMO-1, the apoptosis rate was (16.79±1.62) % and (18.15±1.36) % respectively, while transfected with pwtp53+pMDM2, the rate was decreased to (5.17±1.23) %. The apoptosis rate was (14.06±1.84) % in the cells transfected with pwtp53+pMDM2+pSUMO-1, significantly higher than that in the cells Transfected with pwtp53+pMDM2 (P<0.01). The apoptosis rates in the cells were all less than 2 % and had no significant difference among the groups. It was suggested that in the HepG2 cells, SUMO-1 can increase the apoptosis induced by wild-type p53 through binding to p53 protein, post-translational modification and inhibiting the p53 degradation by MDM2.

  16. Dynamic (G2) Model Design Document, 24590-WTP-MDD-PR-01-002, Rev. 12

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Yueying; Kruger, Albert A.

    2013-12-16

    The Hanford Tank Waste Treatment and Immobilization Plant (WTP) Statement of Work (Department of Energy Contract DE-AC27-01RV14136, Section C) requires the contractor to develop and use process models for flowsheet analyses and pre-operational planning assessments. The Dynamic (G2) Flowsheet is a discrete-time process model that enables the project to evaluate impacts to throughput from eventdriven activities such as pumping, sampling, storage, recycle, separation, and chemical reactions. The model is developed by the Process Engineering (PE) department, and is based on the Flowsheet Bases, Assumptions, and Requirements Document (24590-WTP-RPT-PT-02-005), commonly called the BARD. The terminologies of Dynamic (G2) Flowsheet and Dynamic (G2) Model are interchangeable in this document. The foundation of this model is a dynamic material balance governed by prescribed initial conditions, boundary conditions, and operating logic. The dynamic material balance is achieved by tracking the storage and material flows within the plant as time increments. The initial conditions include a feed vector that represents the waste compositions and delivery sequence of the Tank Farm batches, and volumes and concentrations of solutions in process equipment before startup. The boundary conditions are the physical limits of the flowsheet design, such as piping, volumes, flowrates, operation efficiencies, and physical and chemical environments that impact separations, phase equilibriums, and reaction extents. The operating logic represents the rules and strategies of running the plant.

  17. [Establishment of a model for evaluating hypolipidemic effect in HepG2 cells].

    Science.gov (United States)

    Niu, Yucun; Lü, Na; Li, Ying; Zhao, Dan; Sun, Changhao

    2010-03-01

    To establish a model of evaluating hypolipidemic effect in vitro. Adding cholesterol to the culture medium for HepG2 cells to induce a hypercholesterolemia model. The content of cellular cholesterol and the expression of protein regulating cholesterol metabolism in HepG2 cells were determined. The validation of the model was identified by lovastatin, a widely used cholesterol-lowering drug. Free fatty acid was added to the culture medium for HepG2 cells to induce a hypertriglyceridemia model. The content of cellular triglyceride and the absorption rate of free fatty acid were determined. The validation of the model was identified by fenofibrate, a triglyceride-lowering drug. Cellular cholesterol content was increased and the expression of HMG-CoA redutase, SREBP-2 and LDLR were decreased after adding cholesterol and 25-hydrocholesterol to the culture medium. Cellular cholesterol was decreased and the expression of SREBP-2 and LDLR were up-regulated by Lovastatin. The absorption of oleic acid in cells was up to 40% after adding oleic acid (50 micromol) to the culture medium for 6 h. The absorption of free fatty acid was increased but the content of cellular triglyceride was not increased in cells by Fenofibrate. This model might be an effective method for screening and assessing functional factors for lowing plasma lipids.

  18. The inhibition of polo kinase by matrimony maintains G2 arrest in the meiotic cell cycle.

    Directory of Open Access Journals (Sweden)

    Youbin Xiang

    2007-12-01

    Full Text Available Many meiotic systems in female animals include a lengthy arrest in G2 that separates the end of pachytene from nuclear envelope breakdown (NEB. However, the mechanisms by which a meiotic cell can arrest for long periods of time (decades in human females have remained a mystery. The Drosophila Matrimony (Mtrm protein is expressed from the end of pachytene until the completion of meiosis I. Loss-of-function mtrm mutants result in precocious NEB. Coimmunoprecipitation experiments reveal that Mtrm physically interacts with Polo kinase (Polo in vivo, and multidimensional protein identification technology mass spectrometry analysis reveals that Mtrm binds to Polo with an approximate stoichiometry of 1:1. Mutation of a Polo-Box Domain (PBD binding site in Mtrm ablates the function of Mtrm and the physical interaction of Mtrm with Polo. The meiotic defects observed in mtrm/+ heterozygotes are fully suppressed by reducing the dose of polo+, demonstrating that Mtrm acts as an inhibitor of Polo. Mtrm acts as a negative regulator of Polo during the later stages of G2 arrest. Indeed, both the repression of Polo expression until stage 11 and the inactivation of newly synthesized Polo by Mtrm until stage 13 play critical roles in maintaining and properly terminating G2 arrest. Our data suggest a model in which the eventual activation of Cdc25 by an excess of Polo at stage 13 triggers NEB and entry into prometaphase.

  19. High Precision Magnetic Field Scanning System for the New Muon g-2 Experiment

    Science.gov (United States)

    Hong, Ran; Muon g-2 collaboration Collaboration

    2017-01-01

    The New Muon g-2 Experiment (E989) at Fermilab will measure the anomalous magnetic moment of muon aμ aiming at a precision of 140 ppb. This new experiment will shed light on the long-standing 3.5 standard deviation between the previous muon g-2 measurement (E821) at Brookhaven National Laboratory and the Standard Model calculation, and potentially discover new physics. The New Muon g-2 Experiment measures the precession frequency of muon in a uniform magnetic field, and the magnetic field experienced by the muons needs to be measured with a precision better than 70 ppb. For the measurement of the magnetic field in the muon storage region, the former trolley system from E821 with 17 NMR probes was refurbished and upgraded with new electronics, probes and a modern motion control system. A test solenoid magnet was set up at Argonne National Laboratory for calibrating the NMR probes and the precision studies of systematic uncertainties. In this presentation, we will describe the trolley motion control scheme, the trolley position measurement methods, the electronic system for activating and reading the NMR probes and the test solenoid facility.

  20. Tea pigments induce cell-cycle arrest and apoptosis in HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    Xu-Dong Jia; Chi Han; Jun-Shi Chen

    2005-01-01

    AIM: To investigate the molecular mechanisms by which tea pigments exert preventive effects on liver carcinogenesis.METHODS: HepG2 cells were seeded at a density of 5×105/well in six-well culture dishes and incubated overnight. The cells then were treated with various concentrations of tea pigments over 3 d, harvested by trypsinization, and counted using a hemocytometer. Flow cytometric analysis was performed by a flow cytometer after propidium iodide labeling. Bcl-2 and p21WAF1 proteins were determined by Western blotting. In addition, DNA laddering assay was performed on treated and untreated cultured HepG2 cells.RESULTS: Tea pigments inhibited the growth of HepG2 cells in a dose-dependent manner. Flow-cytometric analysis showed that tea pigments arrested cell cycle progression at G1 phase. DNA laddering was used to investigate apoptotic cell death, and the result showed that 100 mg/L of tea pigments caused typical DNA laddering. Our study also showed that tea pigments induced upregulation of p21WAF1 protein and downregulation of Bcl-2 protein.CONCLUSION: Tea pigments induce cell-cycle arrest and apoptosis. Tea pigments may be used as an ideal chemopreventive agent.

  1. Potentiation of resveratrol-induced apoptosis by matrine in human hepatoma HepG2 cells.

    Science.gov (United States)

    Ou, Xiuyuan; Chen, Yan; Cheng, Xinxin; Zhang, Xumeng; He, Qiyang

    2014-12-01

    Resveratrol, a natural polyphenolic phytochemical, has received considerable attention due to its potential chemopreventive and chemotherapeutic properties. In the present study, we first evaluated the growth-inhibitory effect of resveratrol on HepG2 cells and explored the underlying molecular mechanisms. Resveratrol inhibited proliferation and induced apoptosis in HepG2 cells via activation of caspase-9 and caspase-3, upregulation of the Bax/Bcl-2 ratio and induction of p53 expression. Cell cycle analysis demonstrated that resveratrol arrested cell cycle progression in the G1 and S phase. We further focused on the combination of matrine, a natural component extracted from the traditional Chinese medical herb Sophora flavescens Ait., as a mechanism to potentiate the growth-inhibitory effect of resveratrol on HepG2 cells. Both MTT and colony formation assay results indicated that the combined treatment of resveratrol and matrine exhibited a synergistic antiproliferative effect. In addition, resveratrol-induced apoptosis was significantly enhanced by matrine, which could be attributed to activation of caspase-3 and caspase-9, downregulation of survivin, induction of reactive oxygen species (ROS) generation and disruption of mitochondria membrane potential (Δψm). Our findings suggest that the combination treatment of resveratrol and matrine is a promising novel anticancer strategy for liver cancer; it also provides new insights into the mechanisms of combined therapy.

  2. Efficacy of HIV antiviral polyanionic carbosilane dendrimer G2-S16 in the presence of semen

    Science.gov (United States)

    Ceña-Diez, Rafael; García-Broncano, Pilar; de la Mata, Francisco Javier; Gómez, Rafael; Muñoz-Fernández, Mª Ángeles

    2016-01-01

    The development of a safe and effective microbicide to prevent the sexual transmission of human immunodeficiency virus (HIV)-1 is urgently needed. Unfortunately, the majority of microbicides, such as poly(L-lysine)-dendrimers, anionic polymers, or antiretrovirals, have proved inactive or even increased the risk of HIV infection in clinical trials, most probably due to the fact that these compounds failed to prevent semen-exposed HIV infection. We showed that G2-S16 dendrimer exerts anti-HIV-1 activity at an early stage of viral replication, blocking the gp120/CD4/CCR5 interaction and providing a barrier to infection for long periods, confirming its multifactorial and nonspecific ability. Previously, we demonstrated that topical administration of G2-S16 prevents HIV transmission in humanized BLT mice without irritation or vaginal lesions. Here, we demonstrated that G2-S16 is active against mock- and semen-exposed HIV-1 and could be a promising microbicide against HIV infection. PMID:27313457

  3. Protection of human HepG2 cells against oxidative stress by cocoa phenolic extract.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Granado Serrano, Ana Belén; Izquierdo-Pulido, María; Bravo, Laura; Goya, Luis

    2008-09-10

    Cocoa is a rich source of flavanols and procyanidin oligomers with antioxidative properties, providing protection against oxidation and nitration. The present study investigated the potential protective effect of a polyphenolic extract from cocoa on cell viability and antioxidant defenses of cultured human HepG2 cells submitted to oxidative stress induced by tert-butylhydroperoxide (t-BOOH). Pretreatment of cells with 0.05-50 microg/mL of cocoa polyphenolic extract (CPE) for 2 or 20 h completely prevented cell damage and enhanced activity of antioxidant enzymes induced by a treatment with t-BOOH. Moreover, lower levels of GSH caused by t-BOOH in HepG2 cells were partly recovered by a pretreatment with CPE. Increased reactive oxygen species (ROS) induced by t-BOOH was dose-dependently prevented when cells were pretreated for 2 or 20 h with CPE. These results show that treatment of HepG2 in culture with CPE (within the physiological range of concentrations) confers a significant protection against oxidation to the cells.

  4. Time-course regulation of survival pathways by epicatechin on HepG2 cells.

    Science.gov (United States)

    Granado-Serrano, Ana Belén; Angeles Martín, María; Goya, Luis; Bravo, Laura; Ramos, Sonia

    2009-02-01

    Polyphenols, such as epicatechin, have been reported to exhibit a wide range of biological activities. The objective of the present study was to investigate the time-dependent regulation by epicatechin of survival/proliferation pathways in HepG2 cells. Treatment of HepG2 cells with 10 micromol/L epicatechin did not result in any cell damage up to 18 h, as evaluated by the lactate dehydrogenase assay. Moreover, the enhanced cell death evoked by an oxidative stress induced with tert-butyl hydroperoxide was prevented in the cells pretreated 4 or 18 h with epicatechin. Epicatechin-induced survival was a rapid event that was accompanied by early and sustained activation of major survival signaling proteins, such as AKT/phosphatidylinositol 3-kinase and extracellular-regulated kinase (activated from 5 min to 18 h), as well as protein kinase C (PKC)-alpha (30 min to 18 h), in concert with unaltered c-jun N-amino terminal kinase levels and early inactivation of key death-related signals like PKC-delta (5 min to 18 h). Additionally, reactive oxygen species generation was transiently reduced when cells were treated with 10 micromol/L epicatechin (15-240 min). These data suggest that epicatechin induces cellular survival through a tight regulation of survival/proliferation pathways that requires the integration of different signals and persists over time, the ultimate effect on HepG2 cells being regulated by the balance among these signals.

  5. Muon’s (g-2): the obstinate deviation from the Standard Model

    CERN Multimedia

    Antonella Del Rosso

    2011-01-01

    It’s been 50 years since a small group at CERN measured the muon (g-2) for the first time. Several other experiments have followed over the years. The latest measurement at Brookhaven (2004) gave a value that obstinately remains about 3 standard deviations away from the prediction of the Standard Model. Francis Farley, one of the fathers of the (g-2) experiments, argues that a statement such as “everything we observe is accounted for by the Standard Model” is not acceptable.   Francis J. M. Farley. Francis J. M. Farley, Fellow of the Royal Society since 1972 and the 1980 winner of the Hughes Medal "for his ultra-precise measurements of the muon magnetic moment, a severe test of quantum electrodynamics and of the nature of the muon", is among the scientists who still look at the (g-2) anomaly as one of the first proofs of the existence of new physics. “Although it seems to be generally believed that all experiments agree with the Stan...

  6. Apoptosis induced by nucleosides in the human hepatoma HepG2

    Institute of Scientific and Technical Information of China (English)

    Suh-Ching Yang; Che-Lin Chiu; Chi-Chang Huang; Jiun-Rong Chen

    2005-01-01

    AIM: To investigate the apoptotic effects of nucleosides on the human hepatoma HepG2.METHODS: The nucleosides included inosine (I), cytidine(C), uridine (U), thymidine (T), adenosine (A), and guanosine (G). Cells were incubated by the mediums with or without nucleosides at 37 ℃ in a 50 mL/L CO2 humidified atmosphere.RESULTS: It was found that the cell viabilities were significantly decreased, when cells were treated with 30 mmol/L I, 30 mmol/L C, 30 mmol/L U, 30 mmol/L T,0.5 mmol/L A, and 0.5 mmol/L G after 12 h incubation (P<0.05). About the apoptotic phenomenon, the cell percentages of sub-G1 cells were significantly increased in the mediums containing nucleosides such as C, U, T,A, and G (P<0.05). Furthermore, the caspase-3 activity was increased, when the cells were incubated with T(P<0.05). The protein expressions of p53 and p21 showed no difference in each group. To investigate the mechanism of apoptosis induced by nucleosides, it was found that the contents of soluble Fas ligand contents were increased in HepG2 cells following I, U, T, and A treatment (P<0.05).But, TNF-α and cytochrome c were undetectable.CONCLUSION: Thymidine may induce the apoptosis in HepG2, but the effective dosages and reactive time must be investigated in the future study. However, the apoptosis-inducing abilities of other nucleosides were still unclear in this study.

  7. Lipid synthesis and secretion in HepG2 cells is not affected by ACTH

    Directory of Open Access Journals (Sweden)

    Nilsson-Ehle Peter

    2010-05-01

    Full Text Available Abstract Apolipoprotein B (apoB containing lipoproteins, i.e. VLDL, LDL and Lp(a, are consequently lowered by ACTH treatment in humans. This is also seen as reduced plasma apoB by 20-30% and total cholesterol by 30-40%, mostly accounted for by a decrease in LDL-cholesterol. Studies in hepatic cell line (HepG2 cells showed that apoB mRNA expression is reduced in response to ACTH incubation and is followed by a reduced apoB secretion, which may hypothesize that ACTH lowering apoB containing lipoproteins in humans may be mediated by the inhibition of hepatic apoB synthesis. This was recently confirmed in vivo in a human postprandial study, where ACTH reduced transient apoB48 elevation from the small intestine, however, the exogenic lipid turnover seemed unimpaired. In the present study we investigated if lipid synthesis and/or secretion in HepG2 cells were also affected by pharmacological levels of ACTH to accompany the reduced apoB output. HepG2 cells were incubated with radiolabelled precursors ([14C]acetate and [3H]glycerol either before or during ACTH stimuli. Cellular and secreted lipids were extracted with chloroform:methanol and separated by the thin layer chromatography (TLC, and [14C]labelled cholesterol and cholesteryl ester and [3H]labelled triglycerides and phospholipids were quantitated by the liquid scintillation counting. It demonstrated that ACTH administration did not result in any significant change in neither synthesis nor secretion of the studied lipids, this regardless of presence or absence of oleic acid, which is known to stabilize apoB and enhance apoB production. The present study suggests that ACTH lowers plasma lipids in humans mainly mediated by the inhibition of apoB synthesis and did not via the reduced lipid synthesis.

  8. Mechanism for G2 phase-specific nuclear export of the kinetochore protein CENP-F.

    Science.gov (United States)

    Loftus, Kyle M; Cui, Heying; Coutavas, Elias; King, David S; Ceravolo, Amanda; Pereiras, Dylan; Solmaz, Sozanne R

    2017-08-03

    Centromere protein F (CENP-F) is a component of the kinetochore and a regulator of cell cycle progression. CENP-F recruits the dynein transport machinery and orchestrates several cell cycle-specific transport events, including transport of the nucleus, mitochondria and chromosomes. A key regulatory step for several of these functions is likely the G2 phase-specific export of CENP-F from the nucleus to the cytosol, where the cytoplasmic dynein transport machinery resides; however, the molecular mechanism of this process is elusive. Here, we have identified 3 phosphorylation sites within the bipartite classical nuclear localization signal (cNLS) of CENP-F. These sites are specific for cyclin-dependent kinase 1 (Cdk1), which is active in G2 phase. Phosphomimetic mutations of these residues strongly diminish the interaction of the CENP-F cNLS with its nuclear transport receptor karyopherin α. These mutations also diminish nuclear localization of the CENP-F cNLS in cells. Notably, the cNLS is phosphorylated in the -1 position, which is important to orient the adjacent major motif for binding into its pocket on karyopherin α. We propose that localization of CENP-F is regulated by a cNLS, and a nuclear export pathway, resulting in nuclear localization during most of interphase. In G2 phase, the cNLS is weakened by phosphorylation through Cdk1, likely resulting in nuclear export of CENP-F via the still active nuclear export pathway. Once CENP-F resides in the cytosol, it can engage in pathways that are important for cell cycle progression, kinetochore assembly and the faithful segregation of chromosomes into daughter cells.

  9. Observations of Sagittarius A* during the pericenter passage of the G2 object with MAGIC

    Science.gov (United States)

    Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Antoranz, P.; Arcaro, C.; Babic, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Borracci, F.; Bretz, T.; Buson, S.; Carosi, A.; Chatterjee, A.; Clavero, R.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Oña Wilhelmi, E.; Di Pierro, F.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; Engelkemeier, M.; Fallah Ramazani, V.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Frantzen, K.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Garrido Terrats, D.; Gaug, M.; Giammaria, P.; Godinović, N.; González Muñoz, A.; Gora, D.; Guberman, D.; Hadasch, D.; Hahn, A.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Hughes, G.; Idec, W.; Kodani, K.; Konno, Y.; Kubo, H.; Kushida, J.; La Barbera, A.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; López-Coto, R.; Majumdar, P.; Makariev, M.; Mallot, K.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Marcote, B.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Miranda, J. M.; Mirzoyan, R.; Moralejo, A.; Moretti, E.; Nakajima, D.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Nishijima, K.; Noda, K.; Nogués, L.; Overkemping, A.; Paiano, S.; Palacio, J.; Palatiello, M.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Pedaletti, G.; Peresano, M.; Perri, L.; Persic, M.; Poutanen, J.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Garcia, J. R.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Saito, T.; Satalecka, K.; Schroeder, S.; Schweizer, T.; Shore, S. N.; Sillanpää, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Stamerra, A.; Steinbring, T.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Thaele, J.; Torres, D. F.; Toyama, T.; Treves, A.; Vanzo, G.; Verguilov, V.; Vovk, I.; Ward, J. E.; Will, M.; Wu, M. H.; Zanin, R.

    2017-05-01

    Context. We present the results of a multi-year monitoring campaign of the Galactic center (GC) with the MAGIC telescopes. These observations were primarily motivated by reports that a putative gas cloud (G2) would be passing in close proximity to the super-massive black hole (SMBH), associated with Sagittarius A*, located at the center of our galaxy. This event was expected to give astronomers a unique chance to study the effect of in-falling matter on the broad-band emission of a SMBH. Aims: We search for potential flaring emission of very-high-energy (VHE; ≥100 GeV) gamma rays from the direction of the SMBH at the GC due to the passage of the G2 object. Using these data we also study the morphology of this complex region. Methods: We observed the GC region with the MAGIC Imaging Atmospheric Cherenkov Telescopes during the period 2012-2015, collecting 67 h of good-quality data. In addition to a search for variability in the flux and spectral shape of the GC gamma-ray source, we use a point-source subtraction technique to remove the known gamma-ray emitters located around the GC in order to reveal the TeV morphology of the extended emission inside that region. Results: No effect of the G2 object on the VHE gamma-ray emission from the GC was detected during the 4 yr observation campaign. We confirm previous measurements of the VHE spectrum of Sagittarius A*, and do not detect any significant variability of the emission from the source. Furthermore, the known VHE gamma-ray emitter at the location of the supernova remnant G0.9+0.1 was detected, as well as the recently discovered VHE source close to the GG radio arc.

  10. Metallomics Study of CdSe/ZnS Quantum Dots in HepG2 Cells.

    Science.gov (United States)

    Peng, Lu; He, Man; Chen, Beibei; Qiao, Yu; Hu, Bin

    2015-10-27

    Toxicity of quantum dots (QDs) has been a hot research concern in the past decade, and there is a lot of challenge in this field. The physicochemical characteristics of QDs can affect their toxicity, while little is known about the specific chemical form of QDs in living cells after incubation so far. In this work, speciation of four CdSe/ZnS QDs in HepG2 cells was carried out from the metallomics' point of view for the first time by using size exclusion chromatography (SEC) coupled with inductively coupled plasma-mass spectrometry (ICP-MS). On the basis of the signal of Cd, two kinds of chemical forms, named as QD-1 and QD-2, were observed in HepG2 cells incubated with CdSe/ZnS QDs. QD-1 was demonstrated to be a kind of QD-like nanoparticles, confirmed by chromatographic retention time, transmission electron microscopy (TEM) characterization, and fluorescence detection. QD-2 was demonstrated to be cadmium-metallothioneins complex (Cd-MTs) by reversed phase liquid chromatography (RPLC) synchronously coupled with ICP-MS and electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS) analysis. Meanwhile, speciation of QDs in HepG2 cells incubated with different conditions was analyzed. With the variation of QDs incubation concentration/time, and elimination time, the species of QD-1 and QD-2 were also observed without other obvious species, and both the amount of QD-1 and QD-2 increased with incubation concentration and time. The obtained results provide valuable information and a strategy for the study of existing chemical form of QDs, greatly benefiting the understanding of QDs toxicity in living cells.

  11. Pinolenic Acid Downregulates Lipid Anabolic Pathway in HepG2 Cells.

    Science.gov (United States)

    Lee, Ah Ron; Han, Sung Nim

    2016-07-01

    Pine nut oil (PNO) was reported to reduce lipid accumulation in the liver. However, the specific effect of pinolenic acid (18:3, all-cis-Δ5,9,12), a unique component of PNO, on lipid metabolism has not been studied. We hypothesized that pinolenic acid downregulates the lipid anabolic pathway in HepG2 cells. HepG2 cells were incubated in serum-free medium supplemented with 50 μM bovine serum albumin (BSA), palmitic acid, oleic acid, γ-linolenic acid, pinolenic acid, eicosapentaenoic acid (EPA), or α-linolenic acid for 24 h. Lipid accumulation was determined by Oil Red O (ORO) staining. The mRNA levels of genes related to fatty acid biosynthesis (SREBP1c, FAS, SCD1, and ACC1), fatty acid oxidation (ACC2, PPARα, CPT1A, and ACADL), cholesterol synthesis (SREBP2 and HMGCR), and lipoprotein uptake (LDLr) and of genes that may be involved in the downregulation of the lipogenic pathway (ACSL3, ACSL4, and ACSL5) were determined by qPCR. LDLR protein levels were measured by Western blot analysis. The mRNA levels of SREBP1c, FAS, and SCD1 were significantly downregulated by pinolenic acid treatment compared to BSA control (53, 54, and 38 % lower, respectively). In addition, the mRNA levels of HMGCR, ACSL3, and LDLr were significantly lower (30, 30, and 43 % lower, respectively), and ACSL4 tended to be lower in the pinolenic acid group (20 % lower, P = 0.082) relative to the control group. In conclusion, pinolenic acid downregulated the lipid anabolic pathway in HepG2 cells by reducing expression of genes related to lipid synthesis, lipoprotein uptake, and the regulation of the lipogenic pathway.

  12. Eurycomanone induce apoptosis in HepG2 cells via up-regulation of p53

    Directory of Open Access Journals (Sweden)

    Zakaria Yusmazura

    2009-06-01

    Full Text Available Abstract Background Eurycomanone is a cytotoxic compound found in Eurycoma longifolia Jack. Previous studies had noted the cytotoxic effect against various cancer cell lines. The aim of this study is to investigate the cytotoxicity against human hepato carcinoma cell in vitro and the mode of action. The cytotoxicity of eurycomanone was evaluated using MTT assay and the mode of cell death was detected by Hoechst 33258 nuclear staining and flow cytometry with Annexin-V/propidium iodide double staining. The protein expression Bax, Bcl-2, p53 and cytochrome C were studied by flow cytometry using a spesific antibody conjugated fluorescent dye to confirm the up-regulation of p53 and Bax in cancer cells. Results The findings suggested that eurycomanone was cytotoxic on cancerous liver cell, HepG2 and less toxic on normal cells Chang's liver and WLR-68. Furthermore, various methods proved that apoptosis was the mode of death in eurycomanone-treated HepG2 cells. The characteristics of apoptosis including chromatin condensation, DNA fragmentation and apoptotic bodies were found following eurycomanone treatment. This study also found that apoptotic process triggered by eurycomanone involved the up-regulation of p53 tumor suppressor protein. The up-regulation of p53 was followed by the increasing of pro-apoptotic Bax and decreasing of anti-apoptotic Bcl-2. The increased of cytochrome C levels in cytosol also results in induction of apoptosis. Conclusion The data suggest that eurycomanone was cytotoxic on HepG2 cells by inducing apoptosis through the up-regulation of p53 and Bax, and down-regulation of Bcl-2.

  13. Inactivation of PTEN is responsible for the survival of Hep G2 cells in response to etoposide-induced damage.

    Science.gov (United States)

    Mukherjee, Ananda; Samanta, Saheli; Karmakar, Parimal

    2011-10-01

    The chemo-resistance character of human hepatocellular carcinoma cells is well known but the anomalies associated with such resistance character are not completely understood. In this study, etoposide-induced signaling events in human hepatocellular carcinoma cell line, Hep G2 has been compared with Chang Liver cells, a normal human liver cell line. Hep G2 cells are resistant to etoposide when compared with Chang Liver cells. Etoposide-induced γH2AX foci in Hep G2 cells are persisted for a longer time without affecting cell cycle, indicating that Hep G2 cells are able to maintain its growth with damaged DNA. Further, Akt signaling pathway is deregulated in Hep G2 cells. The upstream negative regulator of Akt, PTEN remains inactive, as it is hyperphosphorylated in Hep G2 cells. Inhibition of PI-3K pathway by wortmannin partially reverses the etoposide-resistance character of Hep G2 cells. Either Hep G2 or Chang Liver cells when transfected with plasmid carrying active Akt (myr-Akt) become resistance towards etoposide compared to the cells transfected with empty vectors or kinase defective Akt. Transient transfection of wild type PTEN in Hep G2 cells does not change its response towards etoposide whereas Chang Liver cells become sensitive after transfection with same plasmid. These results suggest that inactivation of PTEN, which renders activation of Akt, may contribute largely for the etoposide-resistance character of Hep G2 cells. 2011 Elsevier B.V. All rights reserved.

  14. 关于例外群G2的旧知与新识

    Institute of Scientific and Technical Information of China (English)

    Ilka Agricola; 高燕芳(译); 李福安(校)

    2010-01-01

    1900年6月11日,在德国莱比锡(Leipzig)的一次演讲中,Friedrich Engel(弗里德里希·恩格尔)第一次公开报告了他新近发现的最小例外李群G2的刻画,并且他在给萨克森皇家科学院(the Royal Saxonian Academy of Sciences)的通讯评论中写到:

  15. Characterization of Cubic Graphs G with irt(G = Irt(G = 2

    Directory of Open Access Journals (Sweden)

    Eslahchi Changiz

    2014-08-01

    Full Text Available A subset S of vertices in a graph G is called a total irredundant set if, for each vertex v in G, v or one of its neighbors has no neighbor in S −{v}. The total irredundance number, ir(G, is the minimum cardinality of a maximal total irredundant set of G, while the upper total irredundance number, IR(G, is the maximum cardinality of a such set. In this paper we characterize all cubic graphs G with irt(G = IRt(G = 2

  16. The SM extensions with additional light scalar singlet, nonrenormalizable Yukawa interactions and $(g-2)_{\\mu}$

    CERN Document Server

    Gninenko, S N

    2016-01-01

    We consider the SM extension with additional light real singlet scalar, right-handed neutrino and nonrenormalizable Yukawa interaction for the first two generations. We show that the proposed model can explain the observed $(g - 2)$ muon anomaly. Phenomenological consequences as flavour violating decays $\\tau \\rightarrow \\mu\\mu\\mu, \\mu \\mu e, \\mu e e $ are briefly discussed. We also propose the $U_R(1)$ gauge generalization of the SM with complex scalar singlet and nonzero right-handed charges for the first two generations.

  17. No Microwave Flare of Sagittarius A* around the G2 Periastron Passing

    CERN Document Server

    Tsuboi, Masato; Kameya, Osamu; Yonekura, Yoshinori; Miyamoto, Yusuke; Kaneko, Hiroyuki; Seta, Masumichi; Nakai, Naomasa; Takaba, Hiroshi; Wakamatsu, Ken-ichi; Miyoshi, Makoto; Fukuzaki, Yoshihiro; Uehara, Kenta; Sekido, Mamoru

    2014-01-01

    In order to explore any change caused by the G2 cloud approaching, we have monitored the flux density of Sgr A* at 22 GHz from Feb. 2013 to Aug. 2014 with a sub-array of Japanese VLBI Network . The observation period included the expected periastron dates. The number of observation epochs was 283 days. We have observed no significant microwave enhancement of Sgr A* in the whole observation period. The average flux density in the period is $S=1.23+/-0.33$ Jy. The average is consistent with the usually observed flux density range of Sgr A* at 22 GHz.

  18. Moments of the neutron g2 structure function at intermediate Q2

    Science.gov (United States)

    Solvignon, P.; Liyanage, N.; Chen, J.-P.; Choi, Seonho; Slifer, K.; Aniol, K.; Averett, T.; Boeglin, W.; Camsonne, A.; Cates, G. D.; Chang, C. C.; Chudakov, E.; Craver, B.; Cusanno, F.; Deur, A.; Dutta, D.; Ent, R.; Feuerbach, R.; Frullani, S.; Gao, H.; Garibaldi, F.; Gilman, R.; Glashausser, C.; Gorbenko, V.; Hansen, O.; Higinbotham, D. W.; Ibrahim, H.; Jiang, X.; Jones, M.; Kelleher, A.; Kelly, J.; Keppel, C.; Kim, W.; Korsch, W.; Kramer, K.; Kumbartzki, G.; LeRose, J. J.; Lindgren, R.; Ma, B.; Margaziotis, D. J.; Markowitz, P.; McCormick, K.; Meziani, Z.-E.; Michaels, R.; Moffit, B.; Monaghan, P.; Munoz Camacho, C.; Paschke, K.; Reitz, B.; Saha, A.; Shneor, R.; Singh, J.; Sulkosky, V.; Tobias, A.; Urciuoli, G. M.; Wang, K.; Wijesooriya, K.; Wojtsekhowski, B.; Woo, S.; Yang, J.-C.; Zheng, X.; Zhu, L.; Jefferson Lab E01-012 Collaboration

    2015-07-01

    We present new experimental results for the 3He spin structure function g2 in the resonance region at Q2 values between 1.2 and 3.0 (GeV/c )2. Spin dependent moments of the neutron were extracted. Our main result, the inelastic contribution to the neutron d2 matrix element, was found to be small at =2.4 (GeV/c ) 2 and in agreement with the lattice QCD calculation. The Burkhardt-Cottingham sum rule for 3He and the neutron was tested with the measured data and using the Wandzura-Wilczek relation for the low x unmeasured region.

  19. BMI1 attenuates etoposide-induced G2/M checkpoints via reducing ATM activation.

    Science.gov (United States)

    Wei, F; Ojo, D; Lin, X; Wong, N; He, L; Yan, J; Xu, S; Major, P; Tang, D

    2015-06-04

    The BMI1 protein contributes to stem cell pluripotency and oncogenesis via multiple functions, including its newly identified role in DNA damage response (DDR). Although evidence clearly demonstrates that BMI1 facilitates the repair of double-stranded breaks via homologous recombination (HR), it remains unclear how BMI1 regulates checkpoint activation during DDR. We report here that BMI1 has a role in G2/M checkpoint activation in response to etoposide (ETOP) treatment. Ectopic expression of BMI1 in MCF7 breast cancer and DU145 prostate cancer cells significantly reduced ETOP-induced G2/M arrest. Conversely, knockdown of BMI1 in both lines enhanced the arrest. Consistent with ETOP-induced activation of the G2/M checkpoints via the ATM pathway, overexpression and knockdown of BMI1, respectively, reduced and enhanced ETOP-induced phosphorylation of ATM at serine 1981 (ATM pS1981). Furthermore, the phosphorylation of ATM targets, including γH2AX, threonine 68 (T68) on CHK2 (CHK2 pT68) and serine 15 (S15) on p53 were decreased in overexpression and increased in knockdown BMI1 cells in response to ETOP. In line with the requirement of NBS1 in ATM activation, we were able to show that BMI1 associates with NBS1 and that this interaction altered the binding of NBS1 with ATM. BMI1 consists of a ring finger (RF), helix-turn-helix-turn-helix-turn (HT), proline/serine (PS) domain and two nuclear localization signals (NLS). Although deletion of either RF or HT did not affect the association of BMI1 with NBS1, the individual deletions of PS and one NLS (KRMK) robustly reduced the interaction. Stable expression of these BMI1 mutants decreased ETOP-induced ATM pS1981 and CHK2 pT68, but not ETOP-elicited γH2AX in MCF7 cells. Furthermore, ectopic expression of BMI1 in non-transformed breast epithelial MCF10A cells also compromised ETOP-initiated ATM pS1981 and γH2AX. Taken together, we provide compelling evidence that BMI1 decreases ETOP-induced G2/M checkpoint activation via

  20. Tetrandrine: A Potent Abrogator of G2 Checkpoint Function in Tumor Cells and Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To assess the ability of tetrandrine (Tet) to enhance the sensitivity to irradiation and its mechanism in cell lines of human breast cancer p53-mutant MCF-7/ADR, p53-wild-type MCF-7 and human colon carcinoma p53-mutant HT-29 as well as in C26 colorectal carcinoma-bearing BALB/c mice. Methods MCF-7/ADR, HT-29 and MCF-7 cells were exposed to irradiation in the absence or presence of tetrandrine. The effect of Tet on the cytotoxicity of X-irradiation in these three cells was determined and the effect of tetrandrine on cell cycle arrest induced by irradiation in its absence or presence was studied by flow cytometry, Moreover, mitotic index measurement determined mitosis of cells to enter mitosis. Western blotting was employed to detect cyclin B1 and Cdc2 proteins in extracts from irradiated or non-irradiated cells of MCF-7/ADR, HT-29 and MCF-7 treated with tetrandrine at various concentrations. Tumor growth delay assay was conducted to determine the radio-sensitization of tetrandrine in vivo. Results Clonogenic assay showed that tetrandrine markedly enhanced the lethal effect of X-rays on p53-mutant MCF-7/ADR and HT-29 cells and the sensitization enhancement ratio (SER) of tetrandrine was 1.51 and 1.63, but its SER was only 1.1 in p53-wt MCF-7 cells. Irradiated p53-mutant MCF-7/ADR and HT-29 cells were only arrested in G2/M phase while MCF-7 cells were arrested in G1 and G2/M phases. Radiation-induced G2 phase arrests were abrogated by tetrandrine in a concentration-dependent manner in MCF-7/ADR and HT-29 cells,whereas redistribution within MCF-7 cell cycle changed slightly. The proportion of cells in M phase increased from 1.3% to 14.7% in MCF-7/ADR cells, and from 1.5% to 13.2% in HT-29 cells, but 2.4% to 7.1% in MCF-7 cells. Furthermore, the levels of cyclin B 1 and Cdc2 expression decreased after X-irradiation in MCF-7/ADR and HT-29 cells, and the mitotic index was also lower. Tet could reverse the decrease and induce the irradiated cells to enter mitosis

  1. Nucleon $g-2$ Structure Function at Large $x$ and Quark-Gluons Correlations

    Energy Technology Data Exchange (ETDEWEB)

    Zein-Eddine Meziani

    2009-12-01

    We discuss two recently carried out experiments at Jefferson Lab that measured with precision the spin structure function of the nucleon g2, aiming at the determination of the twist-3 matrix element known as d2 for both the proton and the neutron. This matrix element is related to the average Lorentz color force that a quark experiences just at the instant it is struck. It is also interpreted as a measurement of a linear combination of the electric and magnetic “color polarizability” in the nucleon.

  2. Origin of the ESR signal with g=2.0055 in amorphous silicon

    OpenAIRE

    1990-01-01

    Defect-state wave functions for threefold- and fivefold-coordinated Si atoms in amorphous silicon clusters have been calculated with use of a first-principles linear combination of the atomic orbitals method in order to clarify the origin of the ESR signal with g=2.0055 in amorphous silicon. The wave function of the defect state originating from the threefold-coordinated Si atom is strongly localized on this atom. On the other hand, that for the fivefold-coordinated Si atom is extended on thi...

  3. Essential roles for calcium and calmodulin in G2/M progression in Aspergillus nidulans

    OpenAIRE

    1993-01-01

    nimT encodes a protein in Aspergillus nidulans that is required for tyrosine dephosphorylation of p34cdc2 and has a strong homology to cdc25-type proteins. Conditional mutation of nimT (nimT23 mutation) arrests cells in G2 at the restrictive temperature. After release of the temperature-sensitive nimT23 block, p34cdc2 undergoes tyrosine dephosphorylation and we showed that as cells entered mitosis, a rapid increase in calmodulin was observed. The increase in calmodulin and progression into mi...

  4. Restriction beyond the restriction point: mitogen requirement for G2 passage

    Directory of Open Access Journals (Sweden)

    te Riele Hein

    2006-05-01

    Full Text Available Abstract Cell proliferation is dependent on mitogenic signalling. When absent, normal cells cannot pass the G1 restriction point, resulting in cell cycle arrest. Passage through the G1 restriction point involves inactivation of the retinoblastoma protein family. Consequently, loss of the retinoblastoma protein family leads to loss of the G1 restriction point. Recent work in our lab has revealed that cells possess yet another mechanism that restricts proliferation in the absence of mitogens: arrest in the G2 phase of the cell cycle. Here, we discuss the similarities and differences between these restriction points and the roles of cyclin-dependent kinase inhibitors (CKIs herein.

  5. Cohomology of line bundles on the flag variety for type G_2

    DEFF Research Database (Denmark)

    2012-01-01

    In the case of a simple algebraic group G of type G2 over a field of characteristic p>0 we study the cohomology modules of line bundles on the flag variety for G. Our main result is a complete determination of the vanishing behavior of such cohomology in the case where the line bundles in question...... are induced by characters from the lowest p2-alcoves. When Uq is the quantum group corresponding to G whose parameter q is a complex root of unity of order prime to 6 we give a complete (i.e. covering all characters) description of the vanishing behavior for the corresponding quantized cohomology modules....

  6. On the interrelationship among leptonic g - 2, EDMs and lepton flavor violation

    Science.gov (United States)

    Paradisi, Paride

    2016-04-01

    We present a concise review of the status of charged lepton flavor violation (cLFV) in scenarios beyond the SM. We emphasize that the current experimental resolutions on cLFV processes are already testing territories of new physics (NP) models well beyond the LHC reach. On the other hand, with the expected sensitivities of next-generation experiments, cLFV will become the most powerful probe of NP signals at our disposal. Finally, the interrelationship among leptonic g - 2, EDMs and cLFV will turn out to be of outmost importance to disentangle among different NP scenarios.

  7. Higgs Mass and Muon $g-2$ Anomaly in MSSM with Gauge-Gravity hybrid Mediation

    CERN Document Server

    Zhu, Bin; Li, Tianjun

    2016-01-01

    We propose a gauge mediation model with split messengers to explain the muon $g-2$ anomaly in consistent with $125$ GeV higgs mass requirement. The special properties is that all of color sparticles masses fall into several TeV region due to the large messenger splitting which are well beyond the scope of current LHC Run II limits. Meanwhile, sleptons and electroweakinos are light enough to retain advantages of electroweak supersymmetry. This type of spectrum can be realized by introducing hybrid model which combines gauge and gravity mediation. In addition, this mechanism is also responsible for solving tachyonic problem of slepton sector.

  8. An unusual outbreak of rotavirus genotype G2P[6] during the 2005-2006 epidemic season in Philadelphia.

    Science.gov (United States)

    Clark, H Fred; Lawley, Diane; DiStefano, Daniel; Maliga, Marianne; Kilby, Bronwyn; Kulnis, Greg; Mallette, Laura; DiNubile, Mark J

    2011-06-01

    Most rotavirus gastroenteritis is caused by G1P[8] strains. When G2 infections are encountered, the P type has most often been reported to be P[4]. The purpose of our study was to describe an unusual outbreak of G2P[6] cases. Children presenting to The Children's Hospital of Philadelphia with acute gastroenteritis have been monitored for rotavirus antigen in stool by ELISA (with G-typing if ELISA positive) since 1994-1995. Compared to the last 12 rotavirus seasons before the 2006 introduction of a new rotavirus vaccine, the 2005-2006 season had by far the highest number of evaluable rotavirus infections [n = 275 from September 2005 through June 2006, of which 261 (95%) were G typed] and the greatest number of G2 cases (n = 101, 39% of typed strains). Only 16% of G2 strains were associated with P[4], whereas genotype G2P[6] was responsible for 83% of the G2 infections. Eighty-eight percent of the 84 G2P[6] cases occurred in the 60% of patients who were African-Americans, most of whom were urban residents. Among 157 African-American patients, G2 cases (n = 80; 52%) predominated, including 74 due to G2P[6]. Children <6 months old accounted for 27% of cases overall, but 36% of the G2P[6] cases. G2 rotaviruses caused over a third of the community-acquired rotavirus cases in children presenting to CHOP in 2005-2006, attesting to the potential impact of G2 strains during some epidemics. The large majority of G2 strains had the rare P[6] genotype. Urban African-American children under 6 months of age were disproportionately affected.

  9. B4G2 Induces Mitochondrial Apoptosis by the ROS-Mediated Opening of Ca2+-Dependent Permeability Transition Pores

    Directory of Open Access Journals (Sweden)

    Nan Yao

    2015-09-01

    Full Text Available Background/Aims: Hepatocellular carcinoma (HCC is the most common type of liver cancer. At present, only sorafenib is approved to treat HCC. In this study, we found that a 23-hydroxybetulinic acid derivative, B4G2, exhibited potent antiproliferative activity in HCC cell lines. Methods: We used four HCC cell lines (HepG2, HepG2/ADM, Hep3B and Bel-7402 to evaluate the anti-tumour activity and explore underlying mechanisms by which B4G2 induces apoptosis. Results: Among these cell lines, HepG2 showed the highest sensitivity to B4G2. HepG2 cells treated with B4G2 showed a depolarized mitochondrial membrane potential, released cytochrome c, activated caspase-9 and caspase-3 and cleaved poly ADP-ribose polymerase (PARP. However, Z-VAD-FMK, a pan-caspase inhibitor, did not attenuate B4G2-induced apoptosis, implying that the induction of mitochondrial apoptosis by B4G2 may be independent of caspases. Moreover, pre-treatment with MgCl2, a blocker of Ca2+-dependent permeability transition (PT pores, attenuated the depolarization of the mitochondrial potential and decreased the population of apoptotic cells, indicating that B4G2-induced apoptosis was partly dependent on the opening of the Ca2+-dependent PT pores. B4G2 also increased the levels of intracellular calcium and reactive oxygen species (ROS. Furthermore, an ROS scavenger, N-acetyl-cysteine (NAC, markedly decreased the accumulation of intracellular calcium and apoptosis. Conclusion: This is the first demonstration that B4G2 inhibits the growth of HCC cells and induces mitochondrial apoptosis in hepatocellular carcinoma cells by the ROS-mediated opening of Ca2+-dependent permeability transition pores.

  10. Muon g -2 in gauge mediated supersymmetry breaking models with adjoint messengers

    Science.gov (United States)

    Gogoladze, Ilia; Ün, Cem Salih

    2017-02-01

    We explored the sparticle mass spectrum in light of the muon g -2 anomaly and the little hierarchy problem in a class of the gauge mediated supersymmetry breaking model. Here, the messenger fields transform in the adjoint representation of the Standard Model gauge symmetry. To avoid unacceptably light right-handed slepton masses, the Standard Model is supplemented by the additional U (1 )B-L gauge symmetry. A nonzero U (1 )B-L D term makes the right-handed slepton masses compatible with the current experimental bounds. We show that in the framework of Λ3muon g -2 anomaly and the observed 125 GeV Higgs boson mass can be simultaneously accommodated. The slepton masses in this case are predicted to lie in the few hundred GeV range, which can be tested at the LHC. Despite the heavy colored sparticle spectrum, the little hierarchy problem in this model can be ameliorated, and the electroweak fine-tuning parameter can be as low as 10 or so.

  11. Quercetin induces HepG2 cell apoptosis by inhibiting fatty acid biosynthesis.

    Science.gov (United States)

    Zhao, Peng; Mao, Jun-Min; Zhang, Shu-Yun; Zhou, Ze-Quan; Tan, Yang; Zhang, Yu

    2014-08-01

    Quercetin can inhibit the growth of cancer cells with the ability to act as a 'chemopreventer'. Its cancer-preventive effect has been attributed to various mechanisms, including the induction of cell-cycle arrest and/or apoptosis, as well as its antioxidant functions. Quercetin can also reduce adipogenesis. Previous studies have shown that quercetin has potent inhibitory effects on animal fatty acid synthase (FASN). In the present study, activity of quercetin was evaluated in human liver cancer HepG2 cells. Intracellular FASN activity was calculated by measuring the absorption of NADPH via a spectrophotometer. MTT assay was used to test the cell viability, immunoblot analysis was performed to detect FASN expression levels and the apoptotic effect was detected by Hoechst 33258 staining. In the present study, it was found that quercetin could induce apoptosis in human liver cancer HepG2 cells with overexpression of FASN. This apoptosis was accompanied by the reduction of intracellular FASN activity and could be rescued by 25 or 50 μM exogenous palmitic acids, the final product of FASN-catalyzed synthesis. These results suggested that the apoptosis induced by quercetin was via the inhibition of FASN. These findings suggested that quercetin may be useful for preventing human liver cancer.

  12. GM2Calc: Precise MSSM prediction for $(g - 2)$ of the muon

    CERN Document Server

    Athron, Peter; Fargnoli, Helvecio G; Gnendiger, Christoph; Greifenhagen, Robert; Park, Jae-hyeon; Paßehr, Sebastian; Stöckinger, Dominik; Stöckinger-Kim, Hyejung; Voigt, Alexander

    2015-01-01

    We present GM2Calc, a public C++ program for the calculation of MSSM contributions to the anomalous magnetic moment of the muon, $(g-2)_\\mu$. The code computes $(g-2)_\\mu$ precisely, by taking into account the latest two-loop corrections and by performing the calculation in a physical on-shell renormalization scheme. In particular the program includes a $\\tan\\beta$-resummation so that it is valid for arbitrarily high values of $\\tan\\beta$, as well as fermion/sfermion-loop corrections which lead to non-decoupling effects from heavy squarks. GM2Calc can be run with a standard SLHA input file, internally converting the input into on-shell parameters. Alternatively, input parameters may be specified directly in this on-shell scheme. In both cases the input file allows one to switch on/off individual contributions to study their relative impact. This paper also provides typical usage examples not only in conjunctions with spectrum generators and plotting programs but also as C++ subroutines linked to other program...

  13. GM2Calc: precise MSSM prediction for (g-2) of the muon

    Science.gov (United States)

    Athron, Peter; Bach, Markus; Fargnoli, Helvecio G.; Gnendiger, Christoph; Greifenhagen, Robert; Park, Jae-hyeon; Paßehr, Sebastian; Stöckinger, Dominik; Stöckinger-Kim, Hyejung; Voigt, Alexander

    2016-02-01

    We present GM2Calc, a public C++ program for the calculation of MSSM contributions to the anomalous magnetic moment of the muon, (g-2)_μ . The code computes (g-2)_μ precisely, by taking into account the latest two-loop corrections and by performing the calculation in a physical on-shell renormalization scheme. In particular the program includes a tan β resummation so that it is valid for arbitrarily high values of tan β , as well as fermion/sfermion-loop corrections which lead to non-decoupling effects from heavy squarks. GM2Calc can be run with a standard SLHA input file, internally converting the input into on-shell parameters. Alternatively, input parameters may be specified directly in this on-shell scheme. In both cases the input file allows one to switch on/off individual contributions to study their relative impact. This paper also provides typical usage examples not only in conjunction with spectrum generators and plotting programs but also as C++ subroutines linked to other programs.

  14. Extremal solutions of the S3 model and nilpotent orbits of G2(2)

    Science.gov (United States)

    Kim, Sung-Soo; Lindman Hörnlund, Josef; Palmkvist, Jakob; Virmani, Amitabh

    2010-08-01

    We study extremal black hole solutions of the S3 model (obtained by setting S=T=U in the STU model) using group theoretical methods. Upon dimensional reduction over time, the S3 model exhibits the pseudo-Riemannian coset structure {{G} left/ {{tilde{K}}} right.} with G = G2(2) and tilde{K} = {text{S}}{{text{O}}_0}left( {2,2} right) . We study nilpotent tilde{K} -orbits of G2(2) corresponding to non-rotating single-center extremal solutions. We find six such distinct tilde{K} -orbits. Three of these orbits are supersymmetric, one is non-supersymmetric, and two are unphysical. We write general solutions and discuss examples in all four physical orbits. We show that all solutions in supersymmetric orbits when uplifted to five-dimensional minimal supergravity have single-center Gibbons-Hawking space as their four-dimensional Euclidean hyper-Kähler base space. We construct hitherto unknown extremal (supersymmetric as well as non-supersymmetric) pressureless black strings of minimal five-dimensional supergravity and briefly discuss their relation to black rings.

  15. A proteomic analysis of mushroom polysaccharide-treated HepG2 cells

    Science.gov (United States)

    Chai, Yangyang; Wang, Guibin; Fan, Lili; Zhao, Min

    2016-01-01

    The anti-tumor properties of fungal polysaccharides have gained significant recognition in Asia and tropical America. In this study, the differential expression of proteins in normal HepG2 cells and those treated with polysaccharides that had been isolated from Phellinus linteus (PL), Ganoderma lucidum (GL) and Auricularia auricula (AA) was investigated. Using two-dimensional electrophoresis (2DE), a total of 104 protein spots were determined to be overexpressed in these cells compared with noncancerous regions. A total of 59 differentially expressed proteins were identified through MALDI-TOF-MS. In addition, 400 biological processes (BP), 133 cell components (CC) and 146 molecular functions (MF) were enriched by Gene Ontology (GO) analysis, and 78 KEGG pathways were enriched by pathway enrichment. Protein-Protein Interaction (PPI) analysis demonstrated the interaction networks affected by polysaccharides in HepG2 cells. Then, DJ-1 and 14-3-3 were identified as the key proteins in the networks, and the expression of the mRNA and proteins were evaluated using Real-time quantitative PCR (qRT-PCR) and Western blotting (WB), respectively. The results were in agreement with the 2DE. These results provided information on significant proteins of hepatocellular carcinoma (HCC) and form an important basis for the future development of valuable medicinal mushroom resources. PMID:27020667

  16. G 2-structures and quantization of non-geometric M-theory backgrounds

    Science.gov (United States)

    Kupriyanov, Vladislav G.; Szabo, Richard J.

    2017-02-01

    We describe the quantization of a four-dimensional locally non-geometric M-theory background dual to a twisted three-torus by deriving a phase space star product for deformation quantization of quasi-Poisson brackets related to the nonassociative algebra of octonions. The construction is based on a choice of G 2-structure which defines a nonassociative deformation of the addition law on the seven-dimensional vector space of Fourier momenta. We demonstrate explicitly that this star product reduces to that of the three-dimensional parabolic constant R-flux model in the contraction of M-theory to string theory, and use it to derive quantum phase space uncertainty relations as well as triproducts for the nonassociative geometry of the four-dimensional configuration space. By extending the G 2-structure to a Spin(7)-structure, we propose a 3-algebra structure on the full eight-dimensional M2-brane phase space which reduces to the quasi-Poisson algebra after imposing a particular gauge constraint, and whose deformation quantisation simultaneously encompasses both the phase space star products and the configuration space triproducts. We demonstrate how these structures naturally fit in with previous occurences of 3-algebras in M-theory.

  17. Taurine reduces the secretion of apolipoprotein B100 and lipids in HepG2 cells

    Directory of Open Access Journals (Sweden)

    Nagao Koji

    2008-10-01

    Full Text Available Abstract Background Higher concentrations of serum lipids and apolipoprotein B100 (apoB are major individual risk factors of atherosclerosis and coronary heart disease. Therefore ameliorative effects of food components against the diseases are being paid attention in the affluent countries. The present study was undertaken to investigate the effect of taurine on apoB secretion and lipid metabolism in human liver model HepG2 cells. Results The results demonstrated that an addition of taurine to the culture media reduces triacylglycerol (TG-mass in the cells and the medium. Similarly, cellular cholesterol-mass was decreased. Taurine inhibited the incorporation of [14C] oleate into cellular and medium TG, suggesting the inhibition of TG synthesis. In addition, taurine reduced the synthesis of cellular cholesterol ester and its secretion, suggesting the inhibition of acyl-coenzyme A:cholesterol acyltransferase activity. Furthermore, taurine reduced the secretion of apoB, which is a major protein component of very low-density lipoprotein. Conclusion This is a first report to demonstrate that taurine inhibits the secretion of apoB from HepG2 cells.

  18. Development and Testing of Scintillating Detectors for the Muon g-2 Experiment

    Science.gov (United States)

    Martinez, Benjamin; Diamond, Edward; Sblendorio, Alec; Gray, Frederick

    2016-09-01

    The precise value of the muon's anomalous magnetic moment that was measured at Brookhaven National Laboratory E821 differed by more than three standard deviations from predictions of the Standard Model. The Muon g-2 Experiment at Fermilab will attain a more precise measurement by a factor of three by observing the muon spin precession frequency in a magnetic field. This improved measurement could lead to evidence of physics beyond the Standard Model. A thin-scintillator entrance (T0) counter prototype is being tested for possible use in the experiment to determine the intensity and temporal profile of the beam as it is injected into the muon storage ring. The counter is also being evaluated to determine whether it can monitor undesired particles that arrive after the main beam pulse. The unique design of the entrance counter uses a silicon photomultiplier to read the light output from a scintillator. The progress of the design of the T0 entrance counter along with the results of light output tests from a beta source and the SLAC high-energy electron beam are the primary foci of this presentation. The status of scintillating fiber harp beam monitor detectors that will also be used in the g-2 Experiment to detect the position and width of the muon beam will also be presented. This material is based upon work supported by the National Science Foundation under Grant No. PHY-1505887.

  19. MPICH-G2 : a grid-enabled implementation of the message passing interface.

    Energy Technology Data Exchange (ETDEWEB)

    Karonis, N. T.; Toonen, B.; Foster, I.; Mathematics and Computer Science; Northern Illinois Univ.; Univ. of Chicago

    2003-05-01

    Application development for distributed-computing 'Grids' can benefit from tools that variously hide or enable application-level management of critical aspects of the heterogeneous environment. As part of an investigation of these issues, we have developed MPICH-G2, a Grid-enabled implementation of the Message Passing Interface (MPI) that allows a user to run MPI programs across multiple computers, at the same or different sites, using the same commands that would be used on a parallel computer. This library extends the Argonne MPICH implementation of MPI to use services provided by the Globus Toolkit for authentication, authorization, resource allocation, executable staging, and I/O, as well as for process creation, monitoring, and control. Various performance-critical operations, including startup and collective operations, are configured to exploit network topology information. The library also exploits MPI constructs for performance management; for example, the MPI communicator construct is used for application-level discovery of, and adaptation to, both network topology and network quality-of-service mechanisms. We describe the MPICH-G2 design and implementation, present performance results, and review application experiences, including record-setting distributed simulations.

  20. Metabolic Flux Distribution during Defatting of Steatotic Human Hepatoma (HepG2) Cells.

    Science.gov (United States)

    Yarmush, Gabriel; Santos, Lucas; Yarmush, Joshua; Koundinyan, Srivathsan; Saleem, Mubasher; Nativ, Nir I; Schloss, Rene S; Yarmush, Martin L; Maguire, Timothy J; Berthiaume, Francois

    2016-01-04

    Methods that rapidly decrease fat in steatotic hepatocytes may be helpful to recover severely fatty livers for transplantation. Defatting kinetics are highly dependent upon the extracellular medium composition; however, the pathways involved are poorly understood. Steatosis was induced in human hepatoma cells (HepG2) by exposure to high levels of free fatty acids, followed by defatting using plain medium containing no fatty acids, or medium supplemented with a cocktail of defatting agents previously described before. We measured the levels of 28 extracellular metabolites and intracellular triglyceride, and fed the data into a steady-state mass balance model to estimate strictly intracellular fluxes. We found that during defatting, triglyceride content decreased, while beta-oxidation, the tricarboxylic acid cycle, and the urea cycle increased. These fluxes were augmented by defatting agents, and even more so by hyperoxic conditions. In all defatting conditions, the rate of extracellular glucose uptake/release was very small compared to the internal supply from glycogenolysis, and glycolysis remained highly active. Thus, in steatotic HepG2 cells, glycolysis and fatty acid oxidation may co-exist. Together, these pathways generate reducing equivalents that are supplied to mitochondrial oxidative phosphorylation.

  1. M-theory Potential from the $G_2$ Hitchin Functional in Superspace

    CERN Document Server

    Becker, Katrin; Guha, Sunny; Linch, William D; Robbins, Daniel

    2016-01-01

    We embed the component fields of eleven-dimensional supergravity into a superspace of the form $X\\times Y$ where $X$ is the standard 4D, $N=1$ superspace and $Y$ is a smooth 7-manifold. The eleven-dimensional 3-form gives rise to a tensor hierarchy of superfields gauged by the diffeomorphisms of $Y$. It contains a natural candidate for a $G_2$ structure on $Y$, and being a complex of superforms, defines a superspace Chern-Simons invariant. Adding to this a natural generalization of the Riemannian volume on $X\\times Y$ and freezing the (superspin-$\\frac32$ and 1) supergravity fields on $X$, we obtain an approximation to the eleven-dimensional supergravity action that suffices to compute the scalar potential. In this approximation the action is the sum of the superspace Chern-Simons term and a superspace generalization of the Hitchin functional for $Y$ as a $G_2$-structure manifold. Integrating out auxiliary fields, we obtain the conditions for unbroken supersymmetry and the scalar potential. The latter reprodu...

  2. Measuring the leading hadronic contribution to the muon g-2 via $\\mu\\,e$ scattering

    CERN Document Server

    Abbiendi, G; Marconi, U; Matteuzzi, C; Montagna, G; Nicrosini, O; Passera, M; Piccinini, F; Tenchini, R; Trentadue, L; Venanzoni, G

    2016-01-01

    We propose a new experiment to measure the running of the fine-structure constant in the space-like region by scattering high-energy muons on atomic electrons of a low-Z target through the process $\\mu e \\to \\mu e$. The differential cross section of this process, measured as a function of the squared momentum transfer $t=q^2<0$, provides direct sensitivity to the leading-order hadronic contribution to the muon anomaly $a^{\\rm{HLO}}_{\\mu}$. By using a muon beam of 150 GeV, with an average rate of $\\sim1.3\\times 10^7$ muon/s, currently available at the CERN North Area, a statistical uncertainty of $\\sim 0.3\\%$ can be achieved on $a^{\\rm{HLO}}_{\\mu}$ after two years of data taking. This direct measurement of $a^{\\rm{HLO}}_{\\mu}$ will provide an independent determination, competitive with the time-like dispersive approach, and consolidate the theoretical prediction for the muon $g$-2 in the Standard Model. It will allow therefore a firmer interpretation of the measurements of the future muon $g$-2 experiments ...

  3. The nucleolus stress response is coupled to an ATR-Chk1-mediated G2 arrest.

    Science.gov (United States)

    Ma, Hanhui; Pederson, Thoru

    2013-05-01

    We report experiments on the connection between nucleolar stress and cell cycle progression, using HeLa cells engineered with the fluorescent ubiquitinylation-based cell cycle indicator. Nucleolar stress elicited by brief exposure of cells to a low concentration of actinomycin D that selectively inhibits rRNA synthesis had no effect on traverse of G1 or S, but stalled cells in very late interphase. Additional experiments revealed that a switch occurs during a specific temporal window during nucleolar stress and that the subsequent cell cycle arrest is not triggered simply by the stress-induced decline in the synthesis of rRNA or by a ribosome starvation phenomenon. Further experiments revealed that this nucleolus stress-induced cell cycle arrest involves the action of a G2 checkpoint mediated by the ataxia telangiectasia and Rad3-related protein (ATR)-checkpoint kinase 1 (Chk1) pathway. Based on analysis of the cell cycle stages at which this nucleolar stress effect is put into action, to become manifest later, our results demonstrate a feedforward mechanism that leads to G2 arrest and identify ATR and Chk1 as molecular agents of the requisite checkpoint.

  4. Molecular mechanisms of methylmercury-induced cell death in human HepG2 cells.

    Science.gov (United States)

    Cuello, Susana; Goya, Luis; Madrid, Yolanda; Campuzano, Susana; Pedrero, Maria; Bravo, Laura; Cámara, Carmen; Ramos, Sonia

    2010-05-01

    Methylmercury (MeHg) has been suggested to exert cytotoxicity through multiple mechanisms, but the precise biochemical machinery has not been fully defined. This study was aimed at investigating the time-course (0-24h) effect of 2mg/L MeHg on cell death in human HepG2 cells. MeHg decreased cell viability in a time-dependent manner, which was concomitant with increased LDH leakage, reduced GSH levels, CAT activity and altered activity of the antioxidant enzymes GPx and GR at the longest times of incubation (16 and 24h). Activity of the detoxifying enzyme GST was also early enhanced (2h). Caspase-3 activity reached a maximum value at 8h and continued increased up to 24h. This feature was preceded by an enhancement in the caspase-9 activity (2h), whereas caspase-8 activity remained unchanged. MeHg early diminished Bcl-x(L)/Bcl-x(S) ratio and increased levels of the pro-apoptotic Bax and Bad. Moreover, MeHg-induced cytotoxicity was completely inhibited by the antioxidants (GSH and NAC) and notably by the mitochondrial complex I inhibitor rotenone, but not by the NADH oxidase inhibitor DPI. In summary, MeHg induced an oxidative stress responsible for apoptosis in HepG2 cells through direct activation of the caspase cascade and altered the cellular antioxidant and detoxificant enzymatic system to later provoke necrosis at later stages. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  5. Observations of Sagittarius A* during the pericenter passage of the G2 object with MAGIC

    CERN Document Server

    Ahnen, M L; Antonelli, L A; Antoranz, P; Arcaro, C; Babic, A; Banerjee, B; Bangale, P; de Almeida, U Barres; Barrio, J A; González, J Becerra; Bednarek, W; Bernardini, E; Berti, A; Biasuzzi, B; Biland, A; Blanch, O; Bonnefoy, S; Bonnoli, G; Borracci, F; Bretz, T; Buson, S; Carosi, A; Chatterjee, A; Clavero, R; Colin, P; Colombo, E; Contreras, J L; Cortina, J; Covino, S; Da Vela, P; Dazzi, F; De Angelis, A; De Lotto, B; Wilhelmi, E de Oña; Di Pierro, F; Doert, M; Domínguez, A; Prester, D Dominis; Dorner, D; Doro, M; Einecke, S; Glawion, D Eisenacher; Elsaesser, D; Engelkemeier, M; Ramazani, V Fallah; Fernández-Barral, A; Fidalgo, D; Fonseca, M V; Font, L; Frantzen, K; Fruck, C; Galindo, D; López, R J García; Garczarczyk, M; Terrats, D Garrido; Gaug, M; Giammaria, P; Godinović, N; Muñoz, A González; Gora, D; Guberman, D; Hadasch, D; Hahn, A; Hayashida, M; Herrera, J; Hose, J; Hrupec, D; Hughes, G; Idec, W; Kodani, K; Konno, Y; Kubo, H; Kushida, J; La Barbera, A; Lelas, D; Lindfors, E; Lombardi, S; Longo, F; López, M; López-Coto, R; Majumdar, P; Makariev, M; Mallot, K; Maneva, G; Manganaro, M; Mannheim, K; Maraschi, L; Marcote, B; Mariotti, M; Martínez, M; Mazin, D; Menzel, U; Miranda, J M; Mirzoyan, R; Moralejo, A; Moretti, E; Nakajima, D; Neustroev, V; Niedzwiecki, A; Rosillo, M Nievas; Nilsson, K; Nishijima, K; Noda, K; Nogués, L; Overkemping, A; Paiano, S; Palacio, J; Palatiello, M; Paneque, D; Paoletti, R; Paredes, J M; Paredes-Fortuny, X; Pedaletti, G; Peresano, M; Perri, L; Persic, M; Poutanen, J; Moroni, P G Prada; Prandini, E; Puljak, I; Garcia, J R; Reichardt, I; Rhode, W; Ribó, M; Rico, J; Saito, T; Satalecka, K; Schroeder, S; Schweizer, T; Shore, S N; Sillanpää, A; Sitarek, J; Snidaric, I; Sobczynska, D; Stamerra, A; Steinbring, T; Strzys, M; Surić, T; Takalo, L; Tavecchio, F; Temnikov, P; Terzić, T; Tescaro, D; Teshima, M; Thaele, J; Torres, D F; Toyama, T; Treves, A; Vanzo, G; Verguilov, V; Vovk, I; Ward, J E; Will, M; Wu, M H; Zanin, R

    2016-01-01

    Context. We present the results of a multi-year monitoring campaign of the Galactic Center (GC) with the MAGIC telescopes. These observations were primarily motivated by reports that a putative gas cloud (G2) would be passing in close proximity to the super-massive black hole (SMBH), associated with Sagittarius A*, located at the center of our galaxy. This event was expected to give astronomers a unique chance to study the effect of in-falling matter on the broad-band emission of a SMBH. Aims. We search for potential flaring emission of very-high-energy (VHE; $\\geq$100 GeV) gamma rays from the direction of the SMBH at the GC due to the passage of the G2 object. Using these data we also study the morphology of this complex region. Methods. We observed the GC region with the MAGIC Imaging Atmospheric Cherenkov Telescopes during the period 2012-2015, collecting 67 hours of good-quality data. In addition to a search for variability in the flux and spectral shape of the GC gamma-ray source, we use a point-source s...

  6. Novel dammarane saponins from Gynostemma pentaphyllum and their cytotoxic activities against HepG2 cells.

    Science.gov (United States)

    Piao, Xiang-Lan; Xing, Shao-Fang; Lou, Cai-Xia; Chen, Dao-Jin

    2014-10-15

    Two new dammarane saponins, 2α,3β,12β-trihydroxydammar-20(22),24-diene-3-O-[β-D-glucopyranoxyl(1→2)-β-D-6″-O-acetylglucopyranoside (1, namely damulin C) and 2α,3β,12β-trihydroxydammar-20(21),24-diene-3-O-[β-D-glucopyranoxyl(1→2)-β-D-6″-O-acetylglucopyranoside (2, namely damulin D), were isolated from the ethanol extract of Gynostemma pentaphyllum, which had been heat processed by steaming at 125 °C. The NMR spectroscopic data of the novel saponins were completely assigned by using a combination of 2D NMR experiments including (1)H-(1)H COSY, HSQC, and HMBC. Their cytotoxic activities of human liver adenocarcinoma HepG2 cells were evaluated in vitro. They showed cytotoxicities against HepG2 cell line with IC50 of 40±0.7 and 38±0.5 μg/ml, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Mefloquine inhibits chondrocytic proliferation by arresting cell cycle in G2/M phase.

    Science.gov (United States)

    Li, Qiong; Chen, Zeng-Gan; Xia, Qing; Lin, Jian-Ping; Yan, Zuo-Qin; Yao, Zheng-Jun; Dong, Jian

    2015-01-01

    Mefloquine (MQ), an analog of chloroquine, exhibits a promising cytotoxic activity against carcinoma cell lines and for the treatment of glioblastoma patients. The present study demonstrates the effect of mefloquine on proliferation and cell cycle in chondrocytes. MTT assay and propidium iodide staining were used for the analysis of proliferation and cell cycle distribution, respectively. Western blot analysis was used to examine the expression levels of cyclin B1/cdc2, cdc25c, p21WAF1/CIP1 and p53. The results revealed that mefloquine inhibited the proliferation of chondrocytes and caused cell cycle arrests in the G2/M phase. The proliferation of chondrocytes was reduced to 27% at 40 μM concentration of mefloquine after 48 h. The population of chondrocytes in G2/M phase was found to be 15.7 and 48.4%, respectively at 10 and 40 μM concentration of mefloquine at 48 h following treatment. The expression of the cell cycle regulatory proteins including, cyclin B1/cdc2 and cdc25c was inhibited. On the other hand, mefloquine treatment promoted the expression of p21WAF1/CIP1 and p53 at 40 μM concentration after 48 h. Therefore, mefloquine inhibits proliferation and induces cell cycle arrest in chondrocytes.

  8. Crambescin C1 Exerts a Cytoprotective Effect on HepG2 Cells through Metallothionein Induction

    Directory of Open Access Journals (Sweden)

    María Roel

    2015-07-01

    Full Text Available The Mediterranean marine sponge Crambe crambe is the source of two families of guanidine alkaloids known as crambescins and crambescidins. Some of the biological effects of crambescidins have been previously reported while crambescins have undergone little study. Taking this into account, we performed comparative transcriptome analysis to examine the effect of crambescin-C1 (CC1 on human tumor hepatocarcinoma cells HepG2 followed by validation experiments to confirm its predicted biological activities. We report herein that, while crambescin-A1 has a minor effect on these cells, CC1 protects them against oxidative injury by means of metallothionein induction even at low concentrations. Additionally, at high doses, CC1 arrests the HepG2 cell cycle in G0/G1 and thus inhibits tumor cell proliferation. The findings presented here provide the first detailed approach regarding the different effects of crambescins on tumor cells and provide a basis for future studies on other possible cellular mechanisms related to these bioactivities.

  9. Radio and Millimeter Monitoring of Sgr A*: Spectrum, Variability, and Constraints on the G2 Encounter

    CERN Document Server

    Bower, Geoffrey C; Dexter, Jason; Gurwell, Mark A; Moran, James M; Brunthaler, Andreas; Falcke, Heino; Fragile, P Chris; Maitra, Dipankar; Marrone, Dan; Peck, Alison; Rushton, Anthony; Wright, Melvyn C H

    2015-01-01

    We report new observations with the Very Large Array, Atacama Large Millimeter Array, and Submillimeter Array at frequencies from 1.0 to 355 GHz of the Galactic Center black hole, Sagittarius A*. These observations were conducted between October 2012 and November 2014. While we see variability over the whole spectrum with an amplitude as large as a factor of 2 at millimeter wavelengths, we find no evidence for a change in the mean flux density or spectrum of Sgr A* that can be attributed to interaction with the G2 source. The absence of a bow shock at low frequencies is consistent with a cross-sectional area for G2 that is less than $2 \\times 10^{29}$ cm$^2$. This result fits with several model predictions including a magnetically arrested cloud, a pressure-confined stellar wind, and a stellar photosphere of a binary merger. There is no evidence for enhanced accretion onto the black hole driving greater jet and/or accretion flow emission. Finally, we measure the millimeter wavelength spectral index of Sgr A* ...

  10. The yeast Tor signaling pathway is involved in G2/M transition via polo-kinase.

    Directory of Open Access Journals (Sweden)

    Akio Nakashima

    Full Text Available The target of rapamycin (Tor protein plays central roles in cell growth. Rapamycin inhibits cell growth and promotes cell cycle arrest at G1 (G0. However, little is known about whether Tor is involved in other stages of the cell division cycle. Here we report that the rapamycin-sensitive Tor complex 1 (TORC1 is involved in G2/M transition in S. cerevisiae. Strains carrying a temperature-sensitive allele of KOG1 (kog1-105 encoding an essential component of TORC1, as well as yeast cell treated with rapamycin show mitotic delay with prolonged G2. Overexpression of Cdc5, the yeast polo-like kinase, rescues the growth defect of kog1-105, and in turn, Cdc5 activity is attenuated in kog1-105 cells. The TORC1-Type2A phosphatase pathway mediates nucleocytoplasmic transport of Cdc5, which is prerequisite for its proper localization and function. The C-terminal polo-box domain of Cdc5 has an inhibitory role in nuclear translocation. Taken together, our results indicate a novel function of Tor in the regulation of cell cycle and proliferation.

  11. Biscuit melanoidins of different molecular masses protect human HepG2 cells against oxidative stress.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Rufián-Henares, José Angel; Morales, Francisco José; Bravo, Laura; Goya, Luis

    2009-08-26

    Soluble melanoidins from biscuits were enzymatically solubilized and isolated by sequential ultrafiltration and separated by molecular mass in three different fractions, below 3 kDa, between 3 and 10 kDa, and over 10 kDa; the latter was subsequently digested by simulating gastric plus pancreatic digestive conditions. The four fractions were investigated for their protective effect against an oxidative challenge in HepG2 cells. Pretreatment of cells for 20 h with 0.5-10 microg/mL of any of the four fractions prevented the increased cell damage evoked by the challenge but, except for the intermediate size fraction, did not suppress the increased reactive oxygen species. Antioxidant defenses were rapidly restored after the challenge, and the increase of the oxidative stress biomarker malondialdehyde was prevented by the pretreatment with all but the undigested high molecular mass fraction. The results show that treatment of HepG2 cells with concentrations of biscuit melanoidins within the expected physiological range confers on the cells a significant protection against an oxidative challenge.

  12. Protection of human HepG2 cells against oxidative stress by the flavonoid epicatechin.

    Science.gov (United States)

    Martín, María Angeles; Ramos, Sonia; Mateos, Raquel; Izquierdo-Pulido, María; Bravo, Laura; Goya, Luis

    2010-04-01

    Flavanols, such as epicatechin (EC), constitute an important part of the human diet; they can be found in green tea, grapes and cocoa and possess different biological activities such as antioxidant, anti-inflammatory and anticarcinogenic. This study investigated the potential chemo-protective effect of EC against oxidative stress induced by tert-butylhydroperoxide (t-BOOH) on human HepG2 cells. Cell viability by lactate dehydrogenase assay and markers of oxidative status: reduced glutathione (GSH), malondialdehyde (MDA), reactive oxygen species (ROS), glutathione peroxidase (GPx) and glutathione reductase (GR) were evaluated. Pretreatment of cells with EC for 20 h prevented the enhanced cell damage and GPx and GR activities as well as the decrease in GSH induced by t-BOOH. The increased ROS generation induced by t-BOOH was also partly prevented by a pretreatment for 20 h with EC. In addition, pretreatment of cells with EC for 20 h recovered the t-BOOH-induced MDA concentration to control values. A pretreatment for 2 h with EC did not reduce cell damage but partly recovered GSH, reduced ROS levels and muffled the increase of GPx and GR after exposure to t-BOOH. Treatment of HepG2 cells with concentrations of EC in the micromolar range confers a significant protection against oxidative stress.

  13. Evaluation of $\\alpha(M_{Z}^{2})$ and $(g-2)_{\\mu}$

    CERN Document Server

    Davier, M

    1998-01-01

    This talk summarizes the recent developments in the evaluation of the leading order hadronic contributions to the running of the QED f\\/ine structure constant \\aqed, at $s=M_{\\rm Z}^2$, and to the anomalous magnetic moment of the muon $(g-2)_\\mu$. The accuracy of the theoretical prediction of these observables is limited by the uncertainties on the hadronic contributions. Signif\\/icant improvement has been achieved in a series of new analyses which is presented historically in three steps: (I), use of $\\tau$ spectral functions in addition to \\eee\\ cross sections, (II), extended use of perturbative QCD and (III), application of QCD sum rule techniques. The most precise values obtained are: \\daqedhZ\\,$=(276.3\\pm1.6)\\times10^{-4}$, yielding $\\alpha^{-1}(M_{\\rm Z}^2)=128.933\\pm0.021$, and $a_\\mu^{\\rm had}=(692.4\\pm6.2)\\times 10^{-10}$ with which one f\\/inds for the complete Standard Model prediction $a_\\mu^{\\rm SM}=(11\\,659\\,159.6\\pm6.7)\\times10^{-10}$. For the electron $(g-2)_e$, the hadronic contribution is $a_...

  14. Proanthocyanidins modulate microRNA expression in human HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Anna Arola-Arnal

    Full Text Available Mi(croRNAs are small non-coding RNAs of 18-25 nucleotides in length that modulate gene expression at the post-transcriptional level. These RNAs have been shown to be involved in a several biological processes, human diseases and metabolic disorders. Proanthocyanidins, which are the most abundant polyphenol class in the human diet, have positive health effects on a variety of metabolic disorders such as inflammation, obesity, diabetes and insulin resistance. The present study aimed to evaluate whether proanthocyanidin-rich natural extracts modulate miRNA expression. Using microarray analysis and Q-PCR, we investigated miRNA expression in HepG2 cells treated with proanthocyanidins. Our results showed that when HepG2 cells were treated with grape seed proanthocyanidin extract (GSPE, cocoa proanthocyanidin extract (CPE or pure epigallocatechin gallate isolated from green tea (EGCG, fifteen, six and five differentially expressed miRNAs, respectively, were identified out of 904 mRNAs. Specifically, miR-30b* was downregulated by the three treatments, and treatment with GSPE or CPE upregulated miR-1224-3p, miR-197 and miR-532-3p. Therefore, these results provide evidence of the capacity of dietary proanthocyanidins to influence microRNA expression, suggesting a new mechanism of action of proanthocyanidins.

  15. Metabolic Flux Distribution during Defatting of Steatotic Human Hepatoma (HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Gabriel Yarmush

    2016-01-01

    Full Text Available Methods that rapidly decrease fat in steatotic hepatocytes may be helpful to recover severely fatty livers for transplantation. Defatting kinetics are highly dependent upon the extracellular medium composition; however, the pathways involved are poorly understood. Steatosis was induced in human hepatoma cells (HepG2 by exposure to high levels of free fatty acids, followed by defatting using plain medium containing no fatty acids, or medium supplemented with a cocktail of defatting agents previously described before. We measured the levels of 28 extracellular metabolites and intracellular triglyceride, and fed the data into a steady-state mass balance model to estimate strictly intracellular fluxes. We found that during defatting, triglyceride content decreased, while beta-oxidation, the tricarboxylic acid cycle, and the urea cycle increased. These fluxes were augmented by defatting agents, and even more so by hyperoxic conditions. In all defatting conditions, the rate of extracellular glucose uptake/release was very small compared to the internal supply from glycogenolysis, and glycolysis remained highly active. Thus, in steatotic HepG2 cells, glycolysis and fatty acid oxidation may co-exist. Together, these pathways generate reducing equivalents that are supplied to mitochondrial oxidative phosphorylation.

  16. Measuring the leading hadronic contribution to the muon g-2 via μe scattering

    Energy Technology Data Exchange (ETDEWEB)

    Abbiendi, G.; Marconi, U. [INFN Bologna, Bologna (Italy); Calame, C.M.C.; Nicrosini, O.; Piccinini, F. [INFN Pavia, Pavia (Italy); Matteuzzi, C. [INFN Milano Bicocca, Milan (Italy); Montagna, G. [INFN Pavia, Pavia (Italy); Universita di Pavia, Dipartimento di Fisica, Pavia (Italy); Passera, M. [INFN Padova, Padua (Italy); Tenchini, R. [INFN Pisa, Pisa (Italy); Trentadue, L. [INFN Milano Bicocca, Milan (Italy); Dipartimento di Fisica e Scienze della Terra ' ' M. Melloni' ' , Parma (Italy); Venanzoni, G. [INFN, Laboratori Nazionali di Frascati, Frascati, RM (Italy)

    2017-03-15

    We propose a new experiment to measure the running of the electromagnetic coupling constant in the space-like region by scattering high-energy muons on atomic electrons of a low-Z target through the elastic process μe → μe. The differential cross section of this process, measured as a function of the squared momentum transfer t = q{sup 2} < 0, provides direct sensitivity to the leading-order hadronic contribution to the muon anomaly a{sub μ}{sup HLO}. By using a muon beam of 150 GeV, with an average rate of ∝1.3 x 10{sup 7} muon/s, currently available at the CERN North Area, a statistical uncertainty of ∝0.3% can be achieved on a{sub μ}{sup HLO} after two years of data taking. The direct measurement of a{sub μ}{sup HLO} via μe scattering will provide an independent determination, competitive with the time-like dispersive approach, and consolidate the theoretical prediction for the muon g-2 in the Standard Model. It will allow therefore a firmer interpretation of the measurements of the future muon g-2 experiments at Fermilab and J-PARC. (orig.)

  17. The color and size of chili peppers (Capsicum annuum) influence Hep-G2 cell growth.

    Science.gov (United States)

    Popovich, David G; Sia, Sharon Y; Zhang, Wei; Lim, Mon L

    2014-11-01

    Four types of chili (Capsicum annuum) extracts, categorized according to color; green and red, and size; small and large were studied in Hep-G2 cells. Red small (RS) chili had an LC50 value of 0.378 ± 0.029 compared to green big (GB) 1.034 ± 0.061 and green small (GS) 1.070 ± 0.21 mg/mL. Red big (RB) was not cytotoxic. Capsaicin content was highest in RS and produced a greater percentage sub-G1 cells (6.47 ± 1.8%) after 24 h compared to GS (2.96 ± 1.3%) and control (1.29 ± 0.8%) cells. G2/M phase was reduced by GS compared to RS and control cells. RS at the LC50 concentration contained 1.6 times the amount of pure capsaicin LC50 to achieve the same effect of capsaicin alone. GS and GB capsaicin content at the LC50 value was lower (0.2 and 0.66, respectively) compared to the amount of capsaicin to achieve a similar reduction in cell growth.

  18. GM2Calc. Precise MSSM prediction for (g-2) of the muon

    Energy Technology Data Exchange (ETDEWEB)

    Athron, Peter [Monash Univ., Victoria (Australia). School of Physics; Bach, Markus; Gnendiger, Christoph; Greifenhagen, Robert; Stoeckinger, Dominik; Stoeckinger-Kim, Hyejung [Technische Univ. Dresden (Germany). Inst. fuer Kern- und Teilchenphysik; Fargnoli, Helvecio G. [Lavras Univ. (Brazil). Dept. de Ciencias Exatas; Park, Jae-hyeon [Valencia-CSIC Univ., Burjassot (Spain). Dept. de Fisica Teorica y IFIC; Passehr, Sebastian; Voigt, Alexander [DESY Hamburg (Germany)

    2015-10-15

    We present GM2Calc, a public C++ program for the calculation of MSSM contributions to the anomalous magnetic moment of the muon, (g-2){sub μ}. The code computes (g-2){sub μ} precisely, by taking into account the latest two-loop corrections and by performing the calculation in a physical on-shell renormalization scheme. In particular the program includes a tanβ resummation so that it is valid for arbitrarily high values of tanβ, as well as fermion/sfermion-loop corrections which lead to non-decoupling effects from heavy squarks. GM2Calc can be run with a standard SLHA input file, internally converting the input into on-shell parameters. Alternatively, input parameters may be specified directly in this on-shell scheme. In both cases the input file allows one to switch on/off individual contributions to study their relative impact. This paper also provides typical usage examples not only in conjunction with spectrum generators and plotting programs but also as C++ subroutines linked to other programs.

  19. GM2Calc: precise MSSM prediction for (g - 2) of the muon

    Energy Technology Data Exchange (ETDEWEB)

    Athron, Peter [Monash University, ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics, Melbourne, VIC (Australia); Bach, Markus; Gnendiger, Christoph; Greifenhagen, Robert; Stoeckinger, Dominik; Stoeckinger-Kim, Hyejung [TU Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Fargnoli, Helvecio G. [Universidade Federal de Lavras, Departamento de Ciencias Exatas, Lavras (Brazil); Park, Jae-hyeon [Universitat de Valencia-CSIC, Departament de Fisica Teorica and IFIC, Burjassot (Spain); Passehr, Sebastian; Voigt, Alexander [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany)

    2016-02-15

    We present GM2Calc, a public C++ program for the calculation of MSSM contributions to the anomalous magnetic moment of the muon, (g - 2){sub μ}. The code computes (g - 2){sub μ} precisely, by taking into account the latest two-loop corrections and by performing the calculation in a physical on-shell renormalization scheme. In particular the program includes a tan β resummation so that it is valid for arbitrarily high values of tan β, as well as fermion/sfermion-loop corrections which lead to non-decoupling effects from heavy squarks. GM2Calc can be run with a standard SLHA input file, internally converting the input into on-shell parameters. Alternatively, input parameters may be specified directly in this on-shell scheme. In both cases the input file allows one to switch on/off individual contributions to study their relative impact. This paper also provides typical usage examples not only in conjunction with spectrum generators and plotting programs but also as C++ subroutines linked to other programs. (orig.)

  20. Inhibition of Citrinin-Induced Apoptotic Biochemical Signaling in Human Hepatoma G2 Cells by Resveratrol

    Directory of Open Access Journals (Sweden)

    Chia-Chi Chen

    2009-07-01

    Full Text Available The mycotoxin citrinin (CTN, a natural contaminant in foodstuffs and animal feeds, exerts cytotoxic and genotoxic effects on various mammalian cells. CTN causes cell injury, including apoptosis, but its precise regulatory mechanisms of action are currently unclear. Resveratrol, a member of the phytoalexin family found in grapes and other dietary plants, possesses antioxidant and anti-tumor properties. In the present study, we examined the effects of resveratrol on apoptotic biochemical events in Hep G2 cells induced by CTN. Resveratrol inhibited CTN-induced ROS generation, activation of JNK, loss of mitochondrial membrane potential (MMP, as well as activation of caspase-9, caspase-3 and PAK2. Moreover, resveratrol and the ROS scavengers, NAC and α-tocopherol, abolished CTN-stimulated intracellular oxidative stress and apoptosis. Active JNK was required for CTN-induced mitochondria-dependent apoptotic biochemical changes, including loss of MMP, and activation of caspases and PAK2. Activation of PAK2 was essential for apoptosis triggered by CTN. These results collectively demonstrate that CTN stimulates ROS generation and JNK activation for mitochondria-dependent apoptotic signaling in Hep G2 cells, and these apoptotic biochemical events are blocked by pretreatment with resveratrol, which exerts antioxidant effects.

  1. TGF-β1 promotes human hepatic carcinoma HepG2 cells invasion by upregulating autophagy.

    Science.gov (United States)

    Ma, C-L; Qiao, S; Li, Y-C; Wang, X-F; Sun, R-J; Zhang, X; Qian, R-K; Song, S-D

    2017-06-01

    To study the role of TGF-β1 in autophagy and invasion ability of human hepatic carcinoma HepG2 cells. Cultured HepG2 cells were treated with different concentrations of TGF-β1 for 24 h. The protein expression levels of autophagy relative marker LC3 and Beclin1 were detected by Western blot. The effect of TGF-β1 on invasion ability of HepG2 cells was detected with transwell method. The results demonstrated that TGF-β1 was able to activate autophagy of HepG2 cells in a dose-dependent manner. Autophagy inhibitor 3-methyladenine (3-MA) could reverse TGF-β1 induced autophagy process. Also, TGF-β1 significantly promotes the invasion ability of HepG2 cells; however, this process could effectively reverse by autophagy inhibitor 3-MA. TGF-β1 enhances HepG2 cells invasion by upregulating autophagy.

  2. The Benchmarking of the Government to Employee (G2e) Technology Development: Theoretical Aspects of the Model Construction

    OpenAIRE

    Alvydas Baležentis; Gintarė Paražinskaitė

    2012-01-01

    Purpose—To fill the gap in the currently very rare discussion on the important topic of e-government research—design, development and usage of information and communication technologies for human resource management in the public sector and to formulate theoretical benchmarks for development of the government to employee (G2E) model.Design/methodology/approach—Literature analysis of mostly empirical research from the field of government to government (G2G), government to citizen (G2C) and bus...

  3. Peptide sequences of glycoprotein G-2 discriminate between herpes simplex virus type 2 (HSV-2) and HSV-1 antibodies.

    OpenAIRE

    Levi, M.; Rudén, U; Wahren, B.

    1996-01-01

    The complete herpes simplex virus type 2 envelope glycoprotein G was represented by overlapping synthetic peptides. Herpes simplex virus type 2-specific human seroreactivities were mainly seen against three peptides, peptides G2-64, G2-69, and G2-70, located in the C-terminal part of glycoprotein G. This is, interestingly, a region which has strong homology between herpes simplex virus types 1 and 2. G2-69 was the most herpes simplex virus type 2-specific peptide, reacting with 93% (13 of 14)...

  4. Preparation, optical properties and cell staining of water soluble amine-terminated PAMAM G2.0-Au nanocomposites

    Institute of Scientific and Technical Information of China (English)

    XIA Jin-lan; FU Jin-dian; NIE Zhen-yuan; SHEN li

    2005-01-01

    The solution chemical and optical characteristics of formation of amine-terminated polyamidoamine dendrimer G2.0(NH2-PAMAM G2.0)-Au nanocomposites in the aqueous solution of NH2-PAMAM G2.0 at various mole ratios of Au(Ⅲ) to NH2-PAMAM G2.0 were studied by both UV-visible spectrometry and fluorospectrometry. The NH2-PAMAM G2.0-Au nanocomposites, with a type of structure in which one Au nanoparticle is surrounded by several NH2-PAMAM G2.0 dendrimers, emit strong bluish violet fluorescence, and are uniform, water soluble and biocompatible as well as very stable in frozen conditions. The size of gold nanoparticles in the nanocomposites is about 2.5 nm and decreases with the increase of NH2-PAMAM G2.0 concentration. The NH2-PAMAM G2.0 plays an important role in acting as host or micro-reactor for Au(Ⅲ) before Au(Ⅲ) reduction and acting as dispersant and stabilizer for gold nanoparticles after Au(Ⅲ) reduction. Preliminary experiments of cells staining to human embryonic lung fibroblast cell lines show that the NH2-PAMAM G2.0-Au nanocomposites can be used as optical imaging markers for bioanalyses and medical diagnoses.

  5. A centrosome-autonomous signal that involves centriole disengagement permits centrosome duplication in G2 phase after DNA damage.

    LENUS (Irish Health Repository)

    2010-11-15

    DNA damage can induce centrosome overduplication in a manner that requires G2-to-M checkpoint function, suggesting that genotoxic stress can decouple the centrosome and chromosome cycles. How this happens is unclear. Using live-cell imaging of cells that express fluorescently tagged NEDD1\\/GCP-WD and proliferating cell nuclear antigen, we found that ionizing radiation (IR)-induced centrosome amplification can occur outside S phase. Analysis of synchronized populations showed that significantly more centrosome amplification occurred after irradiation of G2-enriched populations compared with G1-enriched or asynchronous cells, consistent with G2 phase centrosome amplification. Irradiated and control populations of G2 cells were then fused to test whether centrosome overduplication is allowed through a diffusible stimulatory signal, or the loss of a duplication-inhibiting signal. Irradiated G2\\/irradiated G2 cell fusions showed significantly higher centrosome amplification levels than irradiated G2\\/unirradiated G2 fusions. Chicken-human cell fusions demonstrated that centrosome amplification was limited to the irradiated partner. Our finding that only the irradiated centrosome can duplicate supports a model where a centrosome-autonomous inhibitory signal is lost upon irradiation of G2 cells. We observed centriole disengagement after irradiation. Although overexpression of dominant-negative securin did not affect IR-induced centrosome amplification, Plk1 inhibition reduced radiation-induced amplification. Together, our data support centriole disengagement as a licensing signal for DNA damage-induced centrosome amplification.

  6. Problems and Coping Strategies of G2C Administrative Ethics Performance Evaluation%G2 C行政伦理绩效评估的问题及其应对策略

    Institute of Scientific and Technical Information of China (English)

    邢勤锋

    2014-01-01

    In this paper,based on the analysis of G2C administrative ethics,public administration values and China’s administrative reform,the author studies G2C the administrative ethics and the performance evaluation,summarizes the problems and shortcomings of the G2C administra-tive ethics performance evaluation,and proposes some strategies to improve the administrative G2C ethical performance evaluation.%在分析G2 C行政伦理对公共行政价值以及中国行政体制改革的重要意义的基础上,梳理G2 C行政伦理及其绩效评估的现状,归纳总结了现行 G2 C 行政伦理绩效评估存在的问题与不足,提出了完善G2 C行政伦理绩效评估的策略。

  7. Protection of G2 and G3 against CO{sub 2}; La protection contre le CO{sub 2} des ensembles G.2 et G.3

    Energy Technology Data Exchange (ETDEWEB)

    Chassany, J.Ph.; Rodier, J. [Commissariat a l' Energie Atomique, Service de Protection contre les Radiations, Marcoule (France). Centre d' Etudes Nucleaires

    1961-07-01

    The presence of 60.000 m{sup 3} of CO{sub 2} at 15 kg/cm{sup 2} pressure has made necessary to set up a detection and protection system on a scale equal to that used for ionising radiations. Instruments to check CO and CO{sub 2} in the atmosphere carry out measurements continuously, alarm systems give warning if the CO{sub 2} content increases, and the working areas may be surveyed by a whole series of portable instruments. The order for evacuation is given by sirens, and respiratory units are placed at strategic points along the exit paths. (author) [French] La presence de 60000 m{sup 3} de CO{sub 2} a 15 kg/cm{sup 2} de pression a exige la mise en place d'un dispositif de detection et de protection aussi important que celui realise pour les radiations ionisantes. Des appareils de controle d'ambiance pour le CO et le CO{sub 2} effectuent des mesures en permanence, des appareils d'alarme donnent l'alerte en cas d'augmentation de la teneur en CO{sub 2} et tout une serie d'appareils portatifs permettant la surveillance des chantiers. L'evacuation est demandee par sirene et des appareils respiratoires autonomes jalonnent les trajets vers les sorties. (auteur)

  8. 吡非尼酮对肝癌HepG2细胞增殖和凋亡的影响%Effect of Pirfenidone on Proliferation and Apoptosis of Human Hepatocellu-lar Carcinoma HepG2 Cells

    Institute of Scientific and Technical Information of China (English)

    韩枫; 凌心

    2015-01-01

    Objective: To investigate the effect of pirfenidone (PF) on cell proliferation and apoptosis of HepG2 cells in vitro. Methods: The cell proliferation inhibition of HepG2 cells by PF was observed by CCK-8 assay. The morphology of HepG2 cells with Hoechst 33258 staining was observed under a fluores-cent microscope. The apoptosis was analyzed by flow cytometry. Results: PF obviously inhibited the prolif-eration of HepG2 cells in a time and dose dependent manner. Hoechst 33258 staining showed apoptosis was induced after PF treatment. Flow cytometry results showed that PF could induce HepG2 cells apopto-sis, compared with the control group (P<0.01). Conclusion: PF inhibits the proliferation of HepG2 cells probably because of inducing HepG2 cells apoptosis.%目的:研究吡非尼酮(pirfenidone,PF)对人肝癌细胞系HepG2增殖和凋亡的影响。方法:CCK-8法测定不同浓度PF对HepG2细胞增殖活性的影响;Hoechst 33258荧光染色法观察PF处理后HepG2细胞形态的变化;流式细胞仪检测细胞凋亡率。结果:PF对HepG2细胞具有显著增殖抑制作用,并呈浓度和时间依赖性;Hoechst 33258染色可见PF处理后细胞出现典型的凋亡形态学变化;流式细胞仪检测结果显示,与空白组比较,PF处理后的HepG2细胞凋亡率显著增加(P﹤0.01)。结论:PF对人肝癌细胞系HepG2细胞增殖具有抑制作用,且与诱导HepG2细胞凋亡有关。

  9. Collaboration Efficiency Improvement Research Framework for G2G E-government%G2G电子政务协同效率改进的支撑框架研究

    Institute of Scientific and Technical Information of China (English)

    樊博

    2010-01-01

    文章针对我国G2G电子政务的协同效率差的现实问题,从G2G系统的投入产出分析入手,以电子政务顶层设计理论为依托,引入信息系统行为学的决策方法来实现G2G系统协同效率的分析改进.文中首先提出崭新的G2G电子政务协同效率改进的建模框架,进而针对建模框架提出崭新的技术支撑框架,从新的决策视角设计了G2G电子政务协同效率改进的路径.

  10. Leptoquark explanation of $h \\to \\mu\\tau$ and muon $(g-2)$

    CERN Document Server

    Baek, Seungwon

    2016-01-01

    We consider lepton flavor violating Higgs decay, specifically $h \\to \\mu\\tau$, in a leptoquark model. We introduce two scalar leptoquarks with the $SU(3)_c \\times SU(2)_L \\times U(1)_Y$ quantum numbers, $(3,2,7/6)$ and $(3,2,1/6)$, which do not generate the proton decay within renormalizable level. They can mix with each other by interactions with the Standard Model Higgs. The constraint from the charged lepton flavor violating process, $\\tau^{-} \\to \\mu^{-} \\gamma$, is very strong when only one leptoquark contribution is considered. However, we demonstrate that significant cancellation is possible between the two leptoquark contributions. We show that we can explain the CMS (ATLAS) excess in $h \\to \\mu \\tau$. We also show that muon $(g-2)$ anomaly can also be accommodated.

  11. Measuring the Muon g-2 Magnetic Storage Field Via Proton Nuclear Magnetic Resonance

    Science.gov (United States)

    Smith, Matthias; Muon g-2 Collaboration Collaboration

    2016-03-01

    The Muon g - 2 experiment at Fermilab aims to measure the muon anomalous magnetic moment, aμ, to a precision of 140 ppb, using a technique that determines the muon spin precession frequency in the highly uniform magnetic field of a storage ring. Both precession frequency and field determination contribute equally to the final systematic uncertainty. The magnetic field is determined from the measurement of free induction decay (FID) signals provided by a matrix of custom proton nuclear magnetic resonance (pNMR) probes. FID simulations show that we can achieve the required precision for extraction of field values compared to systematic contributions. The recently powered muon storage ring is providing data to evaluate the pNMR measurement results. We will describe the performance to date of this system.

  12. Molecular cloning of GA-suppressed G2 pea genes by cDNA RDA

    Institute of Scientific and Technical Information of China (English)

    朱玉贤; 张翼凤; 李慧英

    1997-01-01

    GA-treated and non-treated G2 pea cDNAs were compared using a newly developed method called cDNA representational difference analysis (cDNA-RDA), and several GA-suppressed mRNAs were found. After cloning of the larger fragments PGAS1-3 ( pea GA-suppressed cDNA 1-3), they were demonstrated to be expressed only in pea tissue not treated with GA3 through Northern analysis. Compared with subtractive hybridization and differ-ential display techniques, this method not only can be easily manipulated but also has a relatively low rate of false posi-tive and is highly repetitive. It is the major progress in molecular cloning techniques.

  13. Decolorization of black liquor from bioethanol G2 production using iron oxide coating sands

    Science.gov (United States)

    Barlianti, Vera; Triwahyuni, Eka; Waluyo, Joko; Sari, Ajeng Arum

    2017-01-01

    Bioethanol G2 production using oil palm empty fruit bunch as raw material consists of four steps, namely pretreatment, hydrolysis, fermentation, and purification process. Pretreatment process generates black liquor that causes serious environmental pollution if it is released to the environment. The objective of this research is studying the ability of iron oxide coating sands to adsorb the color of black liquor. The iron oxide coating sands were synthesized from FeCl3.6H2O with quartz sands as support material. This research was conducted on batch mode using black liquor in various pH values. Result obtained that kind of iron oxide on quartz sands's surface was goethite. The result also indicated decreasing of color intensity of black liquor after adsorption process. This research supports local material utilization in environmental technology development to solve some environmental problems.

  14. Muon g-2 and 125 GeV Higgs in Split-Family Supersymmetry

    CERN Document Server

    Ibe, Masahiro; Yokozaki, Norimi

    2013-01-01

    We discuss the minimal supersymmetric standard model with "split-family" spectrum where the sfermions in the first two generations are in the hundreds GeV to a TeV range while the sfermions in the third generation are in the range of tens TeV. With the split-family spectrum, the deviation of the muon g-2 and the observed Higgs boson mass are explained simultaneously. It is predicted that the gluino and the squarks in the first two generations are within the reach of the LHC experiments in most favored parameter space for the universal gaugino mass, which can be tested by searching for events with missing transverse energy or events with stable charged massive particles. We also point out that the split-family scenario can be consistent with the focus point scenario for the non-universal gaugino masses where the required mu-term is in the hundreds GeV range.

  15. Cloning and analysis of a cDNA encoding acetohydroxy acid isomeroreductase from G2 pea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using cDNA representational difference analysis (cDNA RDA) method, we have successfully isolated a gene fragment whose expression was specifically induced by external GA3 application. Screening a G2 pea cDNA library using this fragment as a probe, we obtained a 2036 bp full-length cDNA. It contains a 1746 bp open reading frame and encodes a protein of 581 amino acids with a theoretical molecular weight of 64 ku. It shares high-level sequence identity with AAIR genes from other plant species. This cDNA was cloned into expression vector and recombinant E. coli DH5α cells with remarkable AAIR enzyme activity were obtained.

  16. Improved DNA condensation, stability, and transfection with alkyl sulfonyl-functionalized PAMAM G2

    Energy Technology Data Exchange (ETDEWEB)

    Rata-Aguilar, Azahara, E-mail: azahara@ugr.es; Maldonado-Valderrama, Julia; Jódar-Reyes, Ana Belén; Ortega-Vinuesa, Juan Luis [University of Granada, Biocolloid and Fluid Physics Group, Department of Applied Physics (Spain); Santoyo-Gonzalez, Francisco [University of Granada, Organic Chemistry Department, Institute of Biotechnology (Spain); Martín-Rodríguez, Antonio [University of Granada, Biocolloid and Fluid Physics Group, Department of Applied Physics (Spain)

    2015-04-15

    In this work, we have used a second-generation PAMAM grafted with octadecyl sulfonyl chains to condense plasmid DNA. The influence of this modification at different levels was investigated by comparison with original PAMAM G2. The condensation process and temporal stability of the complexes was studied with DLS, finding that the aliphatic chains influence DNA compaction via hydrophobic forces and markedly improve the formation and temporal stability of a single populated system with a hydrodynamic diameter below 100 nm. Interaction with a cell membrane model was also evaluated with a pendant drop tensiometer, resulting in further incorporation of the C18-PAMAM dendriplexes onto the interface. The improvement observed in transfection with our C18 grafted PAMAM is ascribed to the size, stability, and interfacial behavior of the complexes, which in turn are consequence of the DNA condensation process and the interactions involved.

  17. Application of chiral resonance Lagrangian theories to the muon g-2

    Energy Technology Data Exchange (ETDEWEB)

    Jegerlehner, Fred [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2013-12-15

    We think that phenomenological resonance Lagrangian models, constrained by global fits from low energy hadron reaction data, can help to improve muon g-2 predictions. The main issue are those contributions which cannot be calculated by perturbative means: the hadronic vacuum polarization (HVP) effects and the hadronic light-by-light (HLbL) scattering contribution. I review recent progress in the evaluation of the HVP contribution within the broken Hidden Local Symmetry (HLS) framework, worked out in collaboration with M. Benayoun, P. David and L. Del-Buono. Our HLS driven estimate reads a{sub {mu}}{sup LO} {sup had} = (688.60{+-}4.24) . 10{sup -10} and we find a{sub {mu}}{sup the} = (11659177.65{+-}5.76) . 10{sup -10}.

  18. The Muon g-2 Experiment Overview and Status as of June 2016

    CERN Document Server

    Holzbauer, J L

    2016-01-01

    The Muon g-2 Experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion, which is a factor of four improvement over the previous E821 measurement at Brookhaven. The experiment will also extend the search for the electric dipole moment (EDM) of the muon by approximately two orders of magnitude, with a sensitivity down to $10^{-21}$ e.cm. Both of these measurements are made by combining a precise measurement of the 1.45T storage ring magnetic field with an analysis of the modulation of the decay rate of higher-energy positrons (from anti-muons), recorded by 24 calorimeters and 3 straw tracking detectors. The recent progress in the alignment of the electrostatic quadrapole plates and the trolley rails inside the vacuum chambers, and in establishing the uniform storage ring magnetic field will be described.

  19. A Tungsten / Scintillating Fiber Electromagnetic Calorimeter Prototype for a High-Rate Muon g-2 Experiment

    CERN Document Server

    McNabb, R; Crnkovic, J D; Hertzog, D W; Kiburg, B; Kunkle, J; Thorsland, E; Webber, D M; Lynch, K R; 10.1016/j.nima.2009.01.007

    2009-01-01

    A compact and fast electromagnetic calorimeter prototype was designed, built, and tested in preparation for a next-generation, high-rate muon g-2 experiment. It uses a simple assembly procedure: alternating layers of 0.5-mm-thick tungsten plates and 0.5-mm-diameter plastic scintillating fiber ribbons. This geometry leads to a detector having a calculated radiation length of 0.69 cm, a Moliere radius of 1.73 cm, and a measured intrinsic sampling resolution term of (11.8\\pm1.1)/\\sqrt{E(GeV)}, in the range 1.5 to 3.5 GeV. The construction procedure, test beam results, and GEANT-4 comparative simulations are described.

  20. Muon g-2 through a flavor structure on soft SUSY terms

    CERN Document Server

    Baez, F V Flores; Mondragon, M

    2015-01-01

    In this work we analyze the possibility to explain the muon anomalous magnetic moment discrepancy within theory and experiment through lepton flavor violation processes. We propose a flavor extended MSSM by considering a hierarchical family structure for the trilinear scalar Soft-Supersymmetric terms of the Lagranagian, present at the SUSY breaking scale. We obtain analytical results for the rotation mass matrix, with the consequence of having non-universal slepton masses and the possibility of leptonic flavour mixing. The one-loop supersymmetric contributions to the leptonic flavour violating process $\\tau \\to \\mu\\gamma$ are calculated in the physical basis, instead of using the well known Mass Insertion Method. We present the regions in parameter space where the muon g-2 problem is either entirely solved or partially reduced through the contribution of these flavor violating processes.

  1. Moments of the neutron $g_2$ structure function at intermediate $Q^2$

    CERN Document Server

    Solvignon, P; Chen, J -P; Choi, Seonho; Slifer, K; Aniol, K; Averett, T; Boeglin, W; Camsonne, A; Cates, G D; Chang, C C; Chudakov, E; Craver, B; Cusanno, F; Deur, A; Dutta, D; Ent, R; Feuerbach, R; Frullani, S; Gao, H; Garibaldi, F; Gilman, R; Glashausser, C; Gorbenko, V; Hansen, O; Higinbotham, D W; Ibrahim, H; Jiang, X; Jones, M; Kelleher, A; Kelly, J; Keppel, C; Kim, W; Korsch, W; Kramer, K; Kumbartzki, G; LeRose, J J; Lindgren, R; Ma, B; Margazioti, D J; Markowitz, P; McCormick, K; Meziani, Z -E; Michaels, R; Moffit, B; Monaghan, P; Camacho, C Munoz; Paschke, K; Reitz, B; Saha, A; Shneor, R; Singh, J; Sulkosky, V; Tobias, A; Urciuoli, G M; Wang, K; Wijesooriya, K; Wojtsekhowski, B; Woo, S; Yang, J -C; Zheng, X; Zhu, L

    2013-01-01

    We present new experimental results of the $^3$He spin structure function $g_2$ in the resonance region at $Q^2$ values between 1.2 and 3.0 (GeV/c)$^2$. Spin dependent moments of the neutron were then extracted. The resonance contribution to the neutron $d_2$ matrix element was found to be small at $\\ $=2.4 (GeV/c)$^2$ and in agreement with the Lattice QCD calculation. The Burkhardt-Cottingham sum rule for neutron was tested with the measured data and using the Wandzura-Wilczek relation for the low $x$ unmeasured region. A small deviation was observed at $Q^2$ values between 0.5 and 1.2 (GeV/c)$^2$ for the neutron.

  2. Muon g-2 at Fermilab: Magnetic Field Preparations for a New Physics Search

    Science.gov (United States)

    Kiburg, Brendan; Muon g-2 Collaboration

    2016-03-01

    The Muon g - 2 experiment at Fermilab will measure the muon's anomalous magnetic moment, aμ, to 140 parts-per-billion. Modern calculations for aμ differ from the current experimental value by 3.6 σ. Our effort will test this discrepancy by collecting 20 times more muons and implementing several upgrades to the well-established storage ring technique. The experiment utilizes a superconducting electromagnet with a 7-meter radius and a uniform 1.45-Tesla magnetic field to store ~104 muons at a time. The times, energies, and locations of the subsequent decay positrons are determined and combined with magnetic field measurements to extract aμ. This talk will provide a brief snapshot of the current discrepancy. The role and requirements of the precision magnetic field will be described. Recent progress to establish the required magnetic field uniformity will be highlighted.

  3. End-to-End Beam Simulations for the New Muon G-2 Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Korostelev, Maxim [Cockcroft Inst. Accel. Sci. Tech.; Bailey, Ian [Lancaster U.; Herrod, Alexander [Liverpool U.; Morgan, James [Fermilab; Morse, William [RIKEN BNL; Stratakis, Diktys [RIKEN BNL; Tishchenko, Vladimir [RIKEN BNL; Wolski, Andrzej [Cockcroft Inst. Accel. Sci. Tech.

    2016-06-01

    The aim of the new muon g-2 experiment at Fermilab is to measure the anomalous magnetic moment of the muon with an unprecedented uncertainty of 140 ppb. A beam of positive muons required for the experiment is created by pion decay. Detailed studies of the beam dynamics and spin polarization of the muons are important to predict systematic uncertainties in the experiment. In this paper, we present the results of beam simulations and spin tracking from the pion production target to the muon storage ring. The end-to-end beam simulations are developed in Bmad and include the processes of particle decay, collimation (with accurate representation of all apertures) and spin tracking.

  4. Splitting Mass Spectra and Muon g-2 in Higgs-Anomaly Mediation

    CERN Document Server

    Yin, Wen

    2016-01-01

    We propose a scenario where only the Higgs multiplets have direct couplings to a supersymmetry (SUSY) breaking sector. The standard model matter multiplets as well as the gauge multiples are sequestered from the SUSY breaking sector; therefore, their masses arise via anomaly mediation at the high energy scale with a gravitino mass of $\\sim$100 TeV. Due to renormalization group running effects from the Higgs soft masses, the masses of the third generation sfermions become O(10) TeV at the low energy scale, while the first and second generation sfermion masses are O(0.1-1) TeV, avoiding the tachyonic slepton problem and flavor changing neutral current problem. With the splitting mass spectrum, the muon g-2 anomaly is explained consistently with the observed Higgs boson mass of 125 GeV. Moreover, the third generation Yukawa couplings are expected to be unified in some regions.

  5. Splitting mass spectra and muon g - 2 in Higgs-anomaly mediation

    Science.gov (United States)

    Yin, Wen; Yokozaki, Norimi

    2016-11-01

    We propose a scenario where only the Higgs multiplets have direct couplings to a supersymmetry (SUSY) breaking sector. The standard model matter multiplets as well as the gauge multiples are sequestered from the SUSY breaking sector; therefore, their masses arise via anomaly mediation at the high energy scale with a gravitino mass of ∼ 100TeV. Due to renormalization group running effects from the Higgs soft masses, the masses of the third generation sfermions become O (10)TeV at the low energy scale, while the first and second generation sfermion masses are O (0.1- 1)TeV, avoiding the tachyonic slepton problem and flavor changing neutral current problem. With the splitting mass spectrum, the muon g - 2 anomaly is explained consistently with the observed Higgs boson mass of 125 GeV. Moreover, the third generation Yukawa couplings are expected to be unified in some regions.

  6. Statistical equations and methods applied to the precision muon (g-2) experiment at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, G.W. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Bousquet, B. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Brown, H.N.; Bunce, G. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Carey, R.M. [Department of Physics, Boston University, Boston, MA 02215 (United States); Cushman, P. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Danby, G.T. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Debevec, P.T. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 55455 (United States); Deile, M.; Deng, H. [Physics Department, Yale University, New Haven, CT 06511 (United States); Deninger, W. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 55455 (United States); Dhawan, S.K. [Physics Department, Yale University, New Haven, CT 06511 (United States); Druzhinin, V.P. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Duong, L. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Efstathiadis, E. [Department of Physics, Boston University, Boston, MA 02215 (United States); Farley, F.J.M. [Physics Department, Yale University, New Haven, CT 06511 (United States); Fedotovich, G.V. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Giron, S. [Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States); Gray, F. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 55455 (United States); Grigoriev, D. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)] (and others)

    2007-09-11

    In the muon (g-2) experiment at Brookhaven National Laboratory, the spin precession frequency {omega}{sub a} is obtained from a standard {chi}{sup 2} minimization fit applied to the time distribution of decay electrons. The unusually high accuracy ({approx}0.5ppm) of the experiment puts stringent requirements on the quality of the fit and the level of understanding of the statistical properties of the fitted parameters. We discuss the properties of the fits and their implications on the derived value for {omega}{sub a}, including estimates of the effect of an imperfect fit function, methods of including additional external information to reduce the error, the effects of splitting the data into many smaller subsets of data, applying different weighting methods to the data using energy information, and various tests of data suitability.

  7. Characterization of dengue virus entry into HepG2 cells

    Directory of Open Access Journals (Sweden)

    Suksanpaisan Lukkana

    2009-02-01

    Full Text Available Abstract Background Despite infections by the dengue virus being a significant problem in tropical and sub-tropical countries, the mechanism by which the dengue virus enters into mammalian cells remains poorly described. Methods A combination of biochemical inhibition, dominant negative transfection of Eps15 and siRNA mediated gene silencing was used to explore the entry mechanism of dengue into HepG2 cells. Results Results were consistent with entry via multiple pathways, specifically via clathrin coated pit mediated endocytosis and macropinocytosis, with clathrin mediated endocytosis being the predominant pathway. Conclusion We propose that entry of the dengue virus to mammalian cells can occur by multiple pathways, and this opens the possibility of the virus being directed to multiple cellular compartments. This would have significant implications in understanding the interaction of the dengue virus with the host cell machinery.

  8. Beam Charge Measurement for the g2p/GEp experiments

    CERN Document Server

    Zhu, Pengjia

    2016-01-01

    The g2p/GEp experiments used a solid NH3 polarized target, where the polarization of the target is sensitive to temperature and radiation. The beam current was limited to 5-100 nA during the experiment to avoid too much depolarization of target (The typical Hall A running condition for beam current is 1 uA to 100 uA). The measured charge was further used to get the accurate physics cross sections. New BCM (Beam Current Monitor) receivers and a DAQ system were used to measure the beam current at such a low current range. A tungsten calorimeter was used to calibrate the BCMs. This technical note summarizes the calibration procedure and the performance of the BCMs.

  9. A new MicroTCA-based waveform digitizer for the Muon g-2 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sweigart, David A. [Cornell U.

    2016-12-15

    We present the design of a new $\\mu$TCA-based waveform digitizer, which will be deployed in the Muon g-2 experiment at Fermilab and will allow our pileup identification requirement to be met. This digitizer features five independent channels, each with 12-bit, 800-MSPS digitization and a 1-Gbit memory buffer. The data storage and readout along with configuration are handled by six Xilinx Kintex-7 FPGAs. In addition, the digitizer is equipped with a mezzanine card for analog signal conditioning prior to digitization, further widening its range of possible applications. The performance results of this design are also presented, highlighting its $0.51 \\pm 0.13$ mV intrinsic noise level and $< 22$ ps intrinsic timing resolution between channels. We believe that its performance, together with its flexible design, could be of interest to future experiments in search of a cost-effective waveform digitizer.

  10. Optimal real-time distributed V2G and G2V management of electric vehicles

    Science.gov (United States)

    Stüdli, Sonja; Crisostomi, Emanuele; Middleton, Richard; Shorten, Robert

    2014-06-01

    This paper exploits the analogy between the electrical grid and modern communication networks to implement Electric Vehicle (EV) battery charging scheduling algorithms inspired by popular communication network techniques. In preliminary works, a similar approach was used to manage the Grid-to-Vehicle (G2V) active power flows. In this paper, we extend this framework to both implement the Vehicle-to-Grid (V2G) concept and to provide reactive power compensation capabilities that do not affect charging times. The ability of the proposed algorithms to optimally share the available/desired power in a fair way, with minimum communication requirements, in a very uncertain, dynamically changing framework, is illustrated through several examples for different scenarios of interest.

  11. Potential for the G2/M arrest assay to predict patient susceptibility to severe reactions following radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Perez, A.; Grabenbauer, G.G.; Sauer, R.; Distel, L.V.R. [Dept. of Radiation Oncology, Friedrich Alexander Univ. Erlangen-Nuremberg (Germany); Sprung, C.N. [Div. of Research, Peter MacCallum Cancer Centre, and Dept. of Biochemistry and Molecular Biology, Melbourne Univ., VIC (Australia)

    2007-02-15

    Background and purpose: cell-cycle regulation and checkpoint activation are crucial factors for radiation-induced DNA damage processing. The G2/M phase arrest was assessed in lymphoblastoid cell lines and phytohemagglutinin-stimulated T-lymphocytes of different radiosensitivities to study the relationship of G2/M arrest to radiosensitivity. Material and methods: G2/M arrest was analyzed after in vitro irradiation by 2 and 5 Gy of ionizing radiation up to 6 days using 17 lymphoblastoid cell lines from healthy individuals, ataxia-telangiectasia (AT) patients, Nijmegen breakage syndrome (NBS) patients and cancer patients with clinically increased radiosensitivity. In a second approach, phytohemagglutinin-stimulated T-lymphocytes from 15 healthy individuals, twelve cancer patients, and five cancer patients hypersensitive to ionizing radiation were studied. Image cytometry was performed to analyze G2/M arrest. Results: two of the three AT cell lines showed markedly increased G2/M arrest compared to controls. NBS cells were comparable to controls up to day 3, but then demonstrated a slightly increased G2/M arrest. Two of the six radiosensitive lymphoblast cell lines and the five radiosensitive cancer patients' T-lymphocytes assayed showed a reduction in G2/M arrest, while healthy individuals showed no difference from cancer patients. Conclusion: the interrelation between G2/M arrest and radiosensitivity is not readily apparent since a variety of radiosensitive cells from patients with radiosensitive syndromes and patients identified as radiosensitive following radiation treatment showed inconsistent G2/M arrest dynamics. Secondary effects, like loss of clonogenicity, G1/S phase arrest and failure of G2/M arrest may contribute to variation of the G2/M arrest endpoint and obscure assessment of cellular radiosensitivity using this method. (orig.)

  12. Simulation platform for direct load control of household appliances. Literature survey and G2 implementation

    Energy Technology Data Exchange (ETDEWEB)

    Kolm, J.; Vlaheli, A.

    1996-10-01

    There is an incentive for the power utilities to look for other ways than building new power stations to satisfy increasing customer power needs. One way to fulfill this demand is by redistributing the available electric power between the different power consumers. This method can successfully be used during high peak hours. The utility is also able to make financial profits selling the redistributed electric power at a higher price to customers with temporary high power demands. Direct Load Control - DLC, a Demand Side Management - DSM tool, is one way to achieve a redistribution of electric power. This masters thesis project consisted in developing a user-friendly simulation platform for domestic appliances combined with an electric power control system to be employed for Direct Load Control. The platform contains the necessary facilities for designing an electrical distribution network model and is implemented in G2, an object-oriented real-time environment. The final application provides an on-line instrument for the utility to control the power consumption over the entire system in terms of dispensing power in an electrical network. The report consists of two main parts. The first part describes a literature survey we systematically compiled to gather literature sources. The second part outlines our design and implementation of the G2 simulation platform for a water-heater model with a Direct Load Control system. The entire simulation platform is designed to allow a flexible change and improvement of the different models. Consequently, our software is a powerful tool for studying a wide range of problems related to a Load Management program involving electrical household loads. 9 refs, 32 figs

  13. Induction of G2/M arrest and apoptosis by sesquiterpene lactones in human melanoma cell lines.

    Science.gov (United States)

    Rozenblat, Sharon; Grossman, Shlomo; Bergman, Margalit; Gottlieb, Hugo; Cohen, Yigal; Dovrat, Sara

    2008-01-15

    Malignant melanoma is a highly aggressive tumor which frequently resists chemotherapy, therefore, the search for new agents for its treatment is of great importance. In this study, we purified the sesquiterpene lactones (SLs), Tomentosin and Inuviscolide from Inula viscosa (Compositae) leaves and studied their anti-cancer potency against human melanoma cell lines in order to develop new agents for melanoma treatment. SLs inhibited the proliferation of three human melanoma cell lines: SK-28, 624 mel and 1363 mel in a dose-dependent manner. We further investigated SLs mechanism of action using SK-28 as a representative cell line model. SLs caused cell-cycle arrest at G(2)/M, accompanied by the appearance of a sub-G0 fraction, indicative of apoptotic cell death. Induction of apoptosis was further confirmed by changes in membrane phospholipids, changes in mitochondrial membrane potential (DeltaPsi) and by detection of Caspase-3 activity. Rapid inhibitory phosphorylation of Cdc2 (Thr14 and Tyr15) was seen early after treatment, followed by a later decrease in the expression level of both Cyclin b1 and Cdc2. Induction of p53 and p21(waf1) proteins and phosphorylation of p53 at Ser15 were also detected early after treatment. The anti-apoptotic proteins, p65 subunit of nuclear factor kappaB (NF-kappaB), and Survivin were reduced in a dose-dependent manner. Taken together, these changes partially explain the ability of the SLs to induce G(2)/M arrest and apoptosis. Induction of apoptosis by Tomentosin and Inuviscolide in human aggressive melanoma cell lines has high pharmacological value and implies that SLs might be developed as new agents for melanoma treatment.

  14. Retroendocytosis of high density lipoproteins by the human hepatoma cell line, HepG2

    Energy Technology Data Exchange (ETDEWEB)

    Kambouris, A.M.; Roach, P.D.; Calvert, G.D.; Nestel, P.J. (CSIRO, Division of Human Nutrition, Adelaide (Australia))

    1990-07-01

    When human HepG2 hepatoma cells were pulsed with 125I-labeled high density lipoproteins (HDL) and chased in fresh medium, up to 65% of the radioactivity released was precipitable with trichloroacetic acid. Cell-internalized 125I-HDL contributed to the release of acid-precipitable material; when cells were treated with trypsin before the chase to remove 125I-HDL bound to the outer cell membrane, 50% of the released material was still acid-precipitable. Characterization of the radioactive material resecreted by trypsinized cells revealed the presence of particles that were similar in size and density to mature HDL and contained intact apolipoproteins (apo) A-I and A-II. The release of internalized label occurred at 37 degrees C but not at 4 degrees C. Monensin, which inhibits endosomal recycling of receptors, decreased the binding of 125I-HDL to cells by 75%, inhibited the release of internalized radioactivity as acid-precipitable material by 80%, and increased the release of acid-soluble material by 90%. In contrast, the lysosomal inhibitor chloroquine increased the association of 125I-HDL to cells by 25%, inhibited the release of precipitable material by 10%, and inhibited the release of acid-soluble radioactivity by 80%. Pre-incubation with cholesterol caused a 50% increase in the specific binding, internalization, and resecretion of HDL label. Cholesterol affected the release of acid-precipitable label much more (+90%) than that of acid-soluble material (+20%). Taken together, these findings suggest that HepG2 cells can bind, internalize, and resecrete HDL by a retroendocytotic process. Furthermore, the results with cholesterol and monensin indicate that a regulated, recycling, receptor-like molecule is involved in the binding and intracellular routing of HDL.

  15. Sodium valproate induces mitochondrial respiration dysfunction in HepG2 in vitro cell model.

    Science.gov (United States)

    Komulainen, Tuomas; Lodge, Tiffany; Hinttala, Reetta; Bolszak, Maija; Pietilä, Mika; Koivunen, Peppi; Hakkola, Jukka; Poulton, Joanna; Morten, Karl J; Uusimaa, Johanna

    2015-05-04

    Sodium valproate (VPA) is a potentially hepatotoxic antiepileptic drug. Risk of VPA-induced hepatotoxicity is increased in patients with mitochondrial diseases and especially in patients with POLG1 gene mutations. We used a HepG2 cell in vitro model to investigate the effect of VPA on mitochondrial activity. Cells were incubated in glucose medium and mitochondrial respiration-inducing medium supplemented with galactose and pyruvate. VPA treatments were carried out at concentrations of 0-2.0mM for 24-72 h. In both media, VPA caused decrease in oxygen consumption rates and mitochondrial membrane potential. VPA exposure led to depleted ATP levels in HepG2 cells incubated in galactose medium suggesting dysfunction in mitochondrial ATP production. In addition, VPA exposure for 72 h increased levels of mitochondrial reactive oxygen species (ROS), but adversely decreased protein levels of mitochondrial superoxide dismutase SOD2, suggesting oxidative stress caused by impaired elimination of mitochondrial ROS and a novel pathomechanism related to VPA toxicity. Increased cell death and decrease in cell number was detected under both metabolic conditions. However, immunoblotting did not show any changes in the protein levels of the catalytic subunit A of mitochondrial DNA polymerase γ, the mitochondrial respiratory chain complexes I, II and IV, ATP synthase, E3 subunit dihydrolipoyl dehydrogenase of pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase and glutathione peroxidase. Our results show that VPA inhibits mitochondrial respiration and leads to mitochondrial dysfunction, oxidative stress and increased cell death, thus suggesting an essential role of mitochondria in VPA-induced hepatotoxicity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Pregnane X receptor protects HepG2 cells from BaP-induced DNA damage.

    Science.gov (United States)

    Naspinski, Christine; Gu, Xinsheng; Zhou, Guo-Dong; Mertens-Talcott, Susanne U; Donnelly, Kirby C; Tian, Yanan

    2008-07-01

    Pregnane X receptor (PXR) is a nuclear receptor that coordinately regulates transcriptional expression of both phase I and phase II metabolizing enzymes. PXR plays an important role in the pharmacokinetics of a broad spectrum of endogenous and xenobiotic compounds and appears to have evolved in part to protect organisms from toxic xenobiotics. Metabolism of benzo[a]pyrene (BaP), a well-established carcinogen and ubiquitous environmental contaminant, can result in either detoxification or bioactivation to its genotoxic forms. Therefore, PXR could modulate the genotoxicity of BaP by changing the balance of the metabolic pathways in favor of BaP detoxification. To examine the role of PXR in BaP genotoxicity, BaP-DNA adduct formation was measured by 32P-postlabeling in BaP-treated parental HepG2 cells and human PXR-transfected HepG2 cells. The presence of transfected PXR significantly reduced the level of adducts relative to parental cells by 50-65% (p BaP. To analyze potential PXR-regulated detoxification pathways in liver cells, a panel of genes involved in phase I and phase II metabolism and excretion was surveyed with real-time quantitative reverse transcription PCR. The messenger RNA levels of CYP1A2, GSTA1, GSTA2, GSTM1, UGT1A6, and BCRP (ABCG2) were significantly higher in cells overexpressing PXR, independent of exposure to BaP. In addition, the total GST enzymatic activity, which favors the metabolic detoxification of BaP, was significantly increased by the presence of PXR (p BaP exposure. Taken together, these results suggest that PXR plays an important role in protection against DNA damage by polycyclic aromatic hydrocarbons (PAHs) such as BaP, and that these protective effects may be through a coordinated regulation of genes involved in xenobiotic metabolism.

  17. Dietary catechins and procyanidins modulate zinc homeostasis in human HepG2 cells.

    Science.gov (United States)

    Quesada, Isabel M; Bustos, Mario; Blay, Mayte; Pujadas, Gerard; Ardèvol, Anna; Salvadó, M Josepa; Bladé, Cinta; Arola, Lluís; Fernández-Larrea, Juan

    2011-02-01

    Catechins and their polymers procyanidins are health-promoting flavonoids found in edible vegetables and fruits. They act as antioxidants by scavenging reactive oxygen species and by chelating the redox-active metals iron and copper. They also behave as signaling molecules, modulating multiple cell signalling pathways and gene expression, including that of antioxidant enzymes. This study aimed at determining whether catechins and procyanidins interact with the redox-inactive metal zinc and at assessing their effect on cellular zinc homeostasis. We found that a grape-seed procyanidin extract (GSPE) and the green tea flavonoid (-)-epigallocatechin-3-gallate (EGCG) bind zinc cations in solution with higher affinity than the zinc-specific chelator Zinquin, and dose-dependently prevent zinc-induced toxicity in the human hepatocarcinoma cell line HepG2, evaluated by the lactate dehydrogenase test. GSPE and EGCG hinder intracellular accumulation of total zinc, measured by atomic flame absorption spectrometry, concomitantly increasing the level of cytoplasmic labile zinc detectable by Zinquin fluorescence. Concurrently, GSPE and EGCG inhibit the expression, evaluated at the mRNA level by quantitative reverse transcriptase-polymerase chain reaction, of zinc-binding metallothioneins and of plasma membrane zinc exporter ZnT1 (SLC30A1), while enhancing the expression of cellular zinc importers ZIP1 (SLC39A1) and ZIP4 (SLC39A4). GSPE and EGCG also produce all these effects when HepG2 cells are stimulated to import zinc by treatment with supplemental zinc or the proinflammatory cytokine interleukin-6. We suggest that extracellular complexation of zinc cations and the elevation of cytoplasmic labile zinc may be relevant mechanisms underlying the modulation of diverse cell signaling and metabolic pathways by catechins and procyanidins.

  18. Cyclosporine A and palmitic acid treatment synergistically induce cytotoxicity in HepG2 cells.

    Science.gov (United States)

    Luo, Yi; Rana, Payal; Will, Yvonne

    2012-06-01

    Immunosuppressant cyclosporine A (CsA) treatment can cause severe side effects. Patients taking immunosuppressant after organ transplantation often display hyperlipidemia and obesity. Elevated levels of free fatty acids have been linked to the etiology of metabolic syndromes, nonalcoholic fatty liver and steatohepatitis. The contribution of free fatty acids to CsA-induced toxicity is not known. In this study we explored the effect of palmitic acid on CsA-induced toxicity in HepG2 cells. CsA by itself at therapeutic exposure levels did not induce detectible cytotoxicity in HepG2 cells. Co-treatment of palmitic acid and CsA resulted in a dose dependent increase in cytotoxicity, suggesting that fatty acid could sensitize cells to CsA-induced cytotoxicity at the therapeutic doses of CsA. A synergized induction of caspase-3/7 activity was also observed, indicating that apoptosis may contribute to the cytotoxicity. We demonstrated that CsA reduced cellular oxygen consumption which was further exacerbated by palmitic acid, implicating that impaired mitochondrial respiration might be an underlying mechanism for the enhanced toxicity. Inhibition of c-Jun N-terminal kinase (JNK) attenuated palmitic acid and CsA induced toxicity, suggesting that JNK activation plays an important role in mediating the enhanced palmitic acid/CsA-induced toxicity. Our data suggest that elevated FFA levels, especially saturated FFA such as palmitic acid, may be predisposing factors for CsA toxicity, and patients with underlying diseases that would elevate free fatty acids may be susceptible to CsA-induced toxicity. Furthermore, hyperlipidemia/obesity resulting from immunosuppressive therapy may aggravate CsA-induced toxicity and worsen the outcome in transplant patients.

  19. Simulation of Sea Ice in FGOALS-g2: Climatology and Late 20th Century Changes

    Institute of Scientific and Technical Information of China (English)

    XU Shiming; SONG Mirong; LIU Jiping; WANG Bin; LI Lijuan; HUANG Wenyu; LIU Li

    2013-01-01

    Sea ice is an important component in the Earth's climate system.Coupled climate system models are indispensable tools for the study of sea ice,its internal processes,interaction with other components,and projection of future changes.This paper evaluates the simulation of sea ice by the Flexible Global Ocean-Atmosphere-Land System model Grid-point Version 2 (FGOALS-g2),in the fifth phase of the Coupled Model Inter-comparison Project (CMIP5),with a focus on historical experiments and late 20th century simulation.Through analysis,we find that FGOALS-g2 produces reasonable Arctic and Antarctic sea ice climatology and variability.Sea ice spatial distribution and seasonal change characteristics are well captured.The decrease of Arctic sea ice extent in the late 20th century is reproduced in simulations,although the decrease trend is lower compared with observations.Simulated Antarctic sea ice shows a reasonable distribution and seasonal cycle with high accordance to the amplitude of winter summer changes.Large improvement is achieved as compared with FGOALS-g1.0 in CMIP3.Diagnosis of atmospheric and oceanic forcing on sea ice reveals several shortcomings and major aspects to improve upon in the future:(1) ocean model improvements to remove the artificial island at the North Pole;(2) higher resolution of the atmosphere model for better simulation of important features such as,among others,the Icelandic Low and westerly wind over the Southern Ocean; and (3) ocean model improvements to accurately receive freshwater input from land,and higher resolution for resolving major water channels in the Canadian Arctic Archipelago.

  20. α-Tocopherol modulates the low density lipoprotein receptor of human HepG2 cells

    Directory of Open Access Journals (Sweden)

    Bottema Cynthia DK

    2003-05-01

    Full Text Available Abstract The aim of this study was to determine the effects of vitamin E (α-tocopherol on the low density lipoprotein (LDL receptor, a cell surface protein which plays an important role in controlling blood cholesterol. Human HepG2 hepatoma cells were incubated for 24 hours with increasing amounts of α, δ, or γ-tocopherol. The LDL receptor binding activity, protein and mRNA, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase mRNA, cell cholesterol and cell lathosterol were measured. The effect of α-tocopherol was biphasic. Up to a concentration of 50 μM, α-tocopherol progressively increased LDL receptor binding activity, protein and mRNA to maximum levels 2, 4 and 6-fold higher than control, respectively. The HMG-CoA reductase mRNA and the cell lathosterol concentration, indices of cholesterol synthesis, were also increased by 40% over control by treatment with 50 μM α-tocopherol. The cell cholesterol concentration was decreased by 20% compared to control at 50 μM α-tocopherol. However, at α-tocopherol concentrations higher than 50 μM, the LDL receptor binding activity, protein and mRNA, the HMG-CoA reductase mRNA and the cell lathosterol and cholesterol concentrations all returned to control levels. The biphasic effect on the LDL receptor was specific for α-tocopherol in that δ and γ-tocopherol suppressed LDL receptor binding activity, protein and mRNA at all concentrations tested despite the cells incorporating similar amounts of the three homologues. In conclusion, α-tocopherol, exhibits a specific, concentration-dependent and biphasic "up then down" effect on the LDL receptor of HepG2 cells which appears to be at the level of gene transcription. Cholesterol synthesis appears to be similarly affected and the cell cholesterol concentration may mediate these effects.

  1. SiC nanoparticles cyto- and genotoxicity to Hep-G2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, Sabrina; Jugan, Mary-Line; Simon-Deckers, Angelique; Carriere, Marie [Laboratoire Pierre Suee, CEA-CNRS UMR9956, IRAMIS, CEA Saclay, 91191 Gif sur Yvette (France)], E-mail: marie.carriere@cea.fr; Leconte, Yann; Herlin-Boime, Nathalie; Mayne-l' Hermite, Martine; Reynaud, Cecile [Laboratoire Francis Perrin, CEA-CNRS URA2453, IRAMIS, CEA Saclay, 91191 Gif sur Yvette (France)

    2009-05-01

    While emerging nanotechnologies have seen significant development in recent years, knowledge on exposure levels as well as data on toxicity of nanoparticles are still quite limited. Indeed, there is a general agreement that development of nanotechnologies may lead to considerable dissemination of nanoparticles in the environment. Nevertheless, questions relative to toxicity versus innocuousness of such materials still remain. Our present study has thus been carried out with the purpose of assessing some aspects of toxicological capacities of three kinds of nano-sized particles: TiO{sub 2} and SiC nanoparticles, as well as multi-walled carbon nanotubes (CNT). In order to address the question of their potential toxicity toward living cells, we chose several cellular models. Assuming inhalation as the most probable exposure scenario, we used A549 alveolar epithelial cells as a model for mammalian primary target organ (lung). Furthermore, we considered that nanoparticles that would deposit into the pulmonary system may be translocated to the circulatory system. Thus, we decided to study the effect of nanoparticles on potentially secondary target organs: liver (WIF-B9, Can-10, HepG2) and kidneys (NRK-52E, LLC-PK1). Herein, we will focus our attention on results obtained on the HepG2 cell line exposed to SiC nanoparticles. Scarce literature exists on SiC nanotoxicology. According to the authors that have already carried out studies on this particular nanoparticle, it would seem that SiC nanoparticles do not induce cytotoxicity. That is one of the reasons of the potential use of these nanoparticles as biological labels [1]. We thus were interested in acquiring more data on biological effects induced by SiC nanoparticles. Furthermore, one of the particular aspects of the present study lies in the fact that we tried to specify the influence of physico-chemical characteristics of nanoparticles on toxicological endpoints (cytotoxicity and genotoxicity)

  2. 水杨酸对人肝癌HepG2细胞体外生长的影响的研究*%Influence of Salicylic Acid on Human Hepatic Cancer HepG2 Cells Growth In-vitro

    Institute of Scientific and Technical Information of China (English)

    林冰; 郎锦义; 雷晴

    2014-01-01

    Objective: Salicylic acid ( SA) and its derivatives have been shown to induce apoptosis in a variety of cancer cells. The aim of this study is to investigate influence of SA on human hepatic cancer HepG2 cells growth in-vitro. Methods:MTT assay was used to determine the effect of SA on viability of HepG2 cells, EdU assay was used to detect the impact of SA on the proliferation activity of HepG2 cells, and the cell cycle progress altered and apoptosis of HepG2 cells induced by SA were determined using flow cytometry ( FCM) . Results:SA reduced significantly viability of hepatic cancer HepG2 cells in a concentration-dependent manner and had an IC50 value of (8. 92 ± 0. 45)mmol/L;EdU assay showed that the red fluorescence produced by incorporation of EdU decreased in HepG2 cells treated with SA for 24hr, thereby depress-ing the proliferation activity of HepG2 cells;FCM assay showed that compared to control, SA induced obviously cell cycle G0/G1-phase arrest ( 65. 5% ± 1. 21% vs. 34. 3% ± 0. 89%, P <0. 05 ) and delayed in entering S phase 24. 2% ± 0. 89% vs. 44. 0% ± 0. 64%, P<0. 05), and promoted apoptosis in HepG2 cells(24. 9% ± 0. 32% vs. 2. 3% ± 0. 11%, P<0. 05). Conclusion:SA would inhibits the growth of HepG2 cells by altering cell cycle progress, depressing prolifera-tion activity and promoting cell apoptosis.%目的:探讨水杨酸( salicylic acid, SA)对人肝癌HepG2细胞体外生长的影响。方法:利用MTT法测定SA对HepG2细胞存活性的作用;利用EdU法检测SA对HepG2细胞增殖活性的影响;利用流式细胞分析法测定SA诱导的HepG2细胞周期进程和凋亡。结果:SA显著且呈浓度依赖的降低人肝癌HepG2细胞的存活率,其半数抑制浓度(IC50)为(8.92±0.45)mmol/L;EdU分析显示,SA作用24hr,EdU掺入的红色荧光强度明显减弱,降低了HepG2细胞的增殖活性;FCM分析显示,与对照比较,SA诱导HepG2细胞周期阻滞于G0/G1期(65.5%±1.21%vs.34.3%±0.89%, P<0.05

  3. 17 CFR 240.15g-2 - Penny stock disclosure document relating to the penny stock market.

    Science.gov (United States)

    2010-04-01

    ... required by paragraph (a) of this section for the period specified in 17 CFR 240.17a-4(b) of this chapter... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Penny stock disclosure document relating to the penny stock market. 240.15g-2 Section 240.15g-2 Commodity and Securities...

  4. Differential genomic effects of six different TiO2 nanomaterials on human liver HepG2 cells

    Science.gov (United States)

    Engineered nanoparticles are reported to cause liver toxicity in vivo. To better assess the mechanism of the in vivo liver toxicity, we used the human hepatocarcinoma cells (HepG2) as a model system. Human HepG2 cells were exposed to 6 TiO2 nanomaterials (with dry primary partic...

  5. Esterification of Ginsenoside Rh2 Enhanced Its Cellular Uptake and Antitumor Activity in Human HepG2 Cells.

    Science.gov (United States)

    Chen, Fang; Deng, Ze-Yuan; Zhang, Bing; Xiong, Zeng-Xing; Zheng, Shi-Lian; Tan, Chao-Li; Hu, Jiang-Ning

    2016-01-13

    Our previous research had indicated that the octyl ester derivative of ginsenoside Rh2 (Rh2-O) might have a higher bioavailability than Rh2 in the Caco-2 cell line. The aim of this study was to investigate the cellular uptake and antitumor effects of Rh2-O in human HepG2 cells as well as its underlying mechanism compared with Rh2. Results showed that Rh2-O exhibited a higher cellular uptake (63.24%) than Rh2 (36.76%) when incubated with HepG2 cells for 24 h. Rh2-O possessed a dose- and time-dependent inhibitory effect against the proliferation of HepG2 cells. The IC50 value of Rh2-O for inhibition of HepG2 cell proliferation was 20.15 μM, which was roughly half the value of Rh2. Rh2-O induced apoptosis of HepG2 cells through a mitochondrial-mediated intrinsic pathway. In addition, the accumulation of ROS was detected in Rh2-O-treated HepG2 cells, which participated in the apoptosis of HepG2 cells. Conclusively, the findings above all suggested that Rh2-O as well as Rh2 inducing HepG2 cells apoptosis might involve similar mechanisms; however, Rh2-O had better antitumor activities than Rh2, probably due to its higher cellular uptake.

  6. The calculation of active Raman modes of -quartz crystal via density functional theory based on B3LYP Hamiltonian in 6–311+G(2d) basis set

    Indian Academy of Sciences (India)

    M Talebian; E Talebian; A Abdi

    2012-05-01

    We obtained an approximation of the force field of -quartz crystal using a new idea of applying density functional theory [J Purton, R Jones, C R A Catlow and M Leslie, Phys. Chem. Minerals 19, 392 (1993)]. Our calculations were based on B3LYP Hamiltonian [A N Lazarev and A P Mirgorodsky, Phys. Chem. Minerals 18, 231 (1991)] in 6−311+G(2d) basis set for H16Si7O6 cluster and included a unit cell of the lattice. The advantage of our method is the increase in the speed of calculations and the better adaption of simulation results with the experimental data.

  7. Pentoxifylline induces apoptosis of HepG2 cells by reducing reactive oxygen species production and activating the MAPK signaling.

    Science.gov (United States)

    Wang, Yan; Dong, Lei; Li, Jing; Luo, Miaosha; Shang, Boxin

    2017-08-15

    Pentoxifylline (PTX) is a methylxanthine derivative and has potent anti-tumor activity. This study aimed at investigating the anti-HCC effects of PTX and associated molecular mechanisms. The effects of varying doses of PTX on viability, cell cycle and apoptosis of HepG2 cells were determined by MTT and flow cytometry, respectively. The effects of PTX on the production of reactive oxygen species (ROS), expression of pro- and anti-apoptotic regulators and activation of the MAPK signaling in HepG2 cells were analyzed by flow cytometry and Western blot assays. The effects of PTX on the growth of implanted HepG2 cells and their apoptosis in mice were examined. Our results indicated that PTX inhibited proliferation of HepG2 cells and induced HepG2 cell cycle arrest at G0/G1 phase and apoptosis in a dose- and time-dependent manner. Treatment with PTX reduced levels of ROS and Bcl-XL expression, but increased caspase 3 and caspase 9 expression and JNK and ERK1/2 phosphorylation in HepG2 cells. Pre-treatment with n-acetyl-l-cysteine (NAC), a ROS scavenger, enhanced PTX-mediated cell cycle arrest, apoptosis and the JNK and ERK MAPK activation, while pre-treatment with SP600125 or PD98509 attenuated PTX-mediated effects in HepG2 cells. Treatment with PTX inhibited the growth of implanted HCC and promoted HCC apoptosis in mice. Our data demonstrate that PTX inhibits proliferation of HepG2 cells and induces HepG2 cell apoptosis by attenuating ROS production and enhancing the MAPK activation in HepG2 cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Cyclosporine A and palmitic acid treatment synergistically induce cytotoxicity in HepG2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yi, E-mail: yi.luo@pfizer.com; Rana, Payal; Will, Yvonne

    2012-06-01

    Immunosuppressant cyclosporine A (CsA) treatment can cause severe side effects. Patients taking immunosuppressant after organ transplantation often display hyperlipidemia and obesity. Elevated levels of free fatty acids have been linked to the etiology of metabolic syndromes, nonalcoholic fatty liver and steatohepatitis. The contribution of free fatty acids to CsA-induced toxicity is not known. In this study we explored the effect of palmitic acid on CsA-induced toxicity in HepG2 cells. CsA by itself at therapeutic exposure levels did not induce detectible cytotoxicity in HepG2 cells. Co-treatment of palmitic acid and CsA resulted in a dose dependent increase in cytotoxicity, suggesting that fatty acid could sensitize cells to CsA-induced cytotoxicity at the therapeutic doses of CsA. A synergized induction of caspase-3/7 activity was also observed, indicating that apoptosis may contribute to the cytotoxicity. We demonstrated that CsA reduced cellular oxygen consumption which was further exacerbated by palmitic acid, implicating that impaired mitochondrial respiration might be an underlying mechanism for the enhanced toxicity. Inhibition of c-Jun N-terminal kinase (JNK) attenuated palmitic acid and CsA induced toxicity, suggesting that JNK activation plays an important role in mediating the enhanced palmitic acid/CsA-induced toxicity. Our data suggest that elevated FFA levels, especially saturated FFA such as palmitic acid, may be predisposing factors for CsA toxicity, and patients with underlying diseases that would elevate free fatty acids may be susceptible to CsA-induced toxicity. Furthermore, hyperlipidemia/obesity resulting from immunosuppressive therapy may aggravate CsA-induced toxicity and worsen the outcome in transplant patients. -- Highlights: ► Palmitic acid and cyclosporine (CsA) synergistically increased cytotoxicity. ► The impairment of mitochondrial functions may contribute to the enhanced toxicity. ► Inhibition of JNK activity attenuated

  9. Dihydrotestosterone regulating apolipoprotein M expression mediates via protein kinase C in HepG2 cells

    Directory of Open Access Journals (Sweden)

    Yi-zhou Ye

    2012-12-01

    Full Text Available Abstract Background Administration of androgens decreases plasma concentrations of high-density lipid cholesterol (HDL-C. However, the mechanisms by which androgens mediate lipid metabolism remain unknown. This present study used HepG2 cell cultures and ovariectomized C57BL/6 J mice to determine whether apolipoprotein M (ApoM, a constituent of HDL, was affected by dihydrotestosterone (DHT. Methods HepG2 cells were cultured in the presence of either DHT, agonist of protein kinase C (PKC, phorbol-12-myristate-13-acetate (PMA, blocker of androgen receptor flutamide together with different concentrations of DHT, or DHT together with staurosporine at different concentrations for 24 hrs. Ovariectomized C57BL/6 J mice were treated with DHT or vehicle for 7d or 14d and the levels of plasma ApoM and livers ApoM mRNA were measured. The mRNA levels of ApoM, ApoAI were determined by real-time RT-PCR. ApoM and ApoAI were determined by western blotting analysis. Results Addition of DHT to cell culture medium selectively down-regulated ApoM mRNA expression and ApoM secretion in a dose-dependent manner. At 10 nM DHT, the ApoM mRNA levels were about 20% lower than in untreated cells and about 40% lower at 1000 nM DHT than in the control cells. The secretion of ApoM into the medium was reduced to a similar extent. The inhibitory effect of DHT on ApoM secretion was not blocked by the classical androgen receptor blocker flutamide but by an antagonist of PKC, Staurosporine. Agonist of PKC, PMA, also reduced ApoM. At 0.5 μM PMA, the ApoM mRNA levels and the secretion of ApoM into the medium were about 30% lower than in the control cells. The mRNA expression levels and secretion of another HDL-associated apolipoprotein AI (ApoAI were not affected by DHT. The levels of plasma ApoM and liver ApoM mRNA of DHT-treated C57BL/6 J mice were lower than those of vehicle-treated mice. Conclusions DHT directly and selectively down-regulated the level of ApoM mRNA and the

  10. The g - 2 muon anomaly in di-muon production with the torsion in LHC

    Science.gov (United States)

    Syromyatnikov, A. G.

    2016-06-01

    It was considered within the framework of the conformal gauge gravitational theory CGTG coupling of the standard model fermions to the axial torsion and preliminary discusses the impact of extra dimensions, in particular, in a five-dimensional space-time with Randall-Sundrum metric, where the fifth dimension is compactified on an S1/Z 2 orbifold, which as it turns out is conformally to the fifth dimension flat Euclidean space with permanent trace of torsion, with a compactification radius R in terms of the radius of a CGTG gravitational screening, through torsion in a process Z → μ+μ- and LHC data. In general, have come to the correct set of the conformal calibration curvature the Faddeev-Popov diagram technique type, that follows directly from dynamics. This leads to the effect of restrictions on neutral spin currents of gauge fields by helicity and the Regge’s form theory. The diagrams reveals the fact of opening of the fine spacetime structure in a process pp → γ/Z/T → μ+μ- with a center-of-mass energy of 14TeV, indicated by dotted lines and texture columns, as a result of p-p collision on 1.3 ṡ 10-18cm scales from geometric shell gauge bosons of the SM continued by the heavy axial torsion resonance, and even by emerging from the inside into the outside of the ultra-light (freely-frozen in muon’s spin) axial torsion. We then evaluate the contribution of the torsion to the muon anomaly to derive new constraints on the torsion parameters. It was obtained that on the πN scattering through the exchange of axial torsion accounting, the nucleon anomalous magnetic moment in the eikonal phase leads to additive additives which is responsible for the spin-flip in the scattering process, the scattering amplitude is classical and characterized by a strong the torsion coupling ηT≅1. So the scattering of particles, occurs as on the Coulomb center with the charge fT This is the base model which is the g-2 muon anomaly. The muon anomaly contribution due to

  11. LHC $\\tau$-rich Tests of Lepton-specific 2HDM for $(g-2)_\\mu$

    CERN Document Server

    Chun, Eung Jin; Takeuchi, Michihisa; Tsai, Yue-Lin Sming

    2015-01-01

    The lepton-sepcific (or type X) 2HDM (L2HDM) is an attractive new physics candidate explaining the muon $g-2$ anomaly requiring a light CP-odd boson $A$ and large $\\tan\\beta$. This scenario leads to $\\tau$-rich signatures, such as $3\\tau$, $4\\tau$ and $4\\tau+W/Z$, which can be readily accessible at the LHC. We first study the whole L2HDM parameter space to identify allowed regions of extra Higgs boson masses as well as two couplings $\\lambda_{hAA}$ and $\\xi_h^l$ which determine the 125 GeV Higgs boson decays $h\\to \\tau^+\\tau^-$ and $h\\to AA/AA^*(\\tau^+\\tau^-)$, respectively. This motivates us to set up two regions of interest: (A) $m_A \\ll m_{H} \\sim m_{H^\\pm}$, and (B) $m_A \\sim m_{H^\\pm} \\sim {\\cal O}(100) \\mbox{GeV} \\ll m_H$, for which derive the current constraints by adopting the chargino-neutralino search at the LHC8, and then analyze the LHC14 prospects by implementing $\\tau$-tagging algorithm. A correlated study of the upcoming precision determination of the 125 GeV Higgs boson decay properties as wel...

  12. LHC 750 GeV diphoton excess and muon $(g-2)$

    CERN Document Server

    Baek, Seungwon

    2016-01-01

    We consider implications of the diphoton excess recently observed at the LHC on the anomalous magnetic dipole moment of the muon $(g-2)_\\mu = 2 a_\\mu$, hypothesizing that the possible 750 GeV resonance is a (pseudo)scalar particle. The (pseudo)scalar-$\\gamma$-$\\gamma$ interaction implied by the diphoton events might generically contribute to $a_\\mu$ via 2-loop Barr-Zee type diagrams in a broad class of models. If the scalar is an $SU(2)_L$ singlet, the new contribution to $a_\\mu$ is much smaller than the current anomaly, $\\Delta a_\\mu \\equiv a_\\mu^{\\rm exp}-a_\\mu^{\\rm SM} \\approx (30 \\pm 10) \\times 10^{-10}$, since the scalar can complete the Barr-Zee diagrams only through its mixing with the Standard Model Higgs boson. If the (pseudo)scalar belongs to an $SU(2)_L$ doublet in an extended Higgs sector, then by contrast, $\\Delta a_\\mu$ can be easily accommodated with the aid of an enhanced Yukawa coupling of the (pseudo)scalar to the muon such as in Type-II or -X two Higgs doublet model.

  13. Amitriptyline induces mitophagy that precedes apoptosis in human HepG2 cells

    Science.gov (United States)

    Villanueva-Paz, Marina; Cordero, Mario D.; Pavón, Ana Delgado; Vega, Beatriz Castejón; Cotán, David; De la Mata, Mario; Oropesa-Ávila, Manuel; Alcocer-Gomez, Elizabet; de Lavera, Isabel; Garrido-Maraver, Juan; Carrascosa, José; Zaderenko, Ana Paula; Muntané, Jordi; de Miguel, Manuel; Sánchez-Alcázar, José Antonio

    2016-01-01

    Systemic treatments for hepatocellular carcinoma (HCC) have been largely unsuccessful. This study investigated the antitumoral activity of Amitriptyline, a tricyclic antidepressant, in hepatoma cells. Amitriptyline-induced toxicity involved early mitophagy activation that subsequently switched to apoptosis. Amitriptyline induced mitochondria dysfunction and oxidative stress in HepG2 cells. Amitriptyline specifically inhibited mitochondrial complex III activity that is associated with decreased mitochondrial membrane potential (∆Ψm) and increased reactive oxygen species (ROS) production. Transmission electron microscopy (TEM) studies revealed structurally abnormal mitochondria that were engulfed by double-membrane structures resembling autophagosomes. Consistent with mitophagy activation, fluorescence microscopy analysis showed mitochondrial Parkin recruitment and colocalization of mitochondria with autophagosome protein markers. Pharmacological or genetic inhibition of autophagy exacerbated the deleterious effects of Amitriptyline on hepatoma cells and led to increased apoptosis. These results suggest that mitophagy acts as an initial adaptive mechanism of cell survival. However persistent mitochondrial damage induced extensive and lethal mitophagy, autophagy stress and autophagolysome permeabilization leading eventually to cell death by apoptosis. Amitriptyline also induced cell death in hepatoma cells lines with mutated p53 and non-sense p53 mutation. Our results support the hypothesis that Amitriptyline-induced mitochondrial dysfunction can be a useful therapeutic strategy for HCC treatment, especially in tumors showing p53 mutations and/or resistant to genotoxic treatments. PMID:27738496

  14. Necrosis of HepG2 cancer cells induced by the vibration of magnetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Biran [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France); Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Bienvenu, Céline [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Mendez-Garza, Juan; Lançon, Pascal; Madeira, Alexandra [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France); Vierling, Pierre [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Di Giorgio, Christophe, E-mail: christophe.di-giorgio@unice.fr [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Bossis, Georges, E-mail: bossis@unice.fr [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France)

    2013-10-15

    Experiments of magnetolysis, i.e., destruction of cells induced with magnetic particles (MPs) submitted to the application of a magnetic field, were conducted on HepG2 cancer cells. We herein demonstrate the usefulness of combining anisotropic MPs with an alternative magnetic field in magnetolysis. Thus, the application of an alternative magnetic field of low frequency (a few Hertz) in the presence of anisotropic, submicronic particles allowed the destruction of cancer cells “in vitro”. We also show that a constant magnetic field is far less efficient than an oscillating one. Moreover, we demonstrate that, at equal particle volume, it is much more efficient to utilize spindle shaped particles rather than spherical ones. In order to get deeper insight into the mechanism of magnetolysis experiments, we performed a study by AFM, which strongly supports that the magnetic field induces the formation of clusters of particles becoming then large enough todamage cell membranes. - Highlights: • Magnetic force was applied on cancer cells through magnetic particles. • The penetration depth was predicted, both for spherical and ellipsoidal particles. • Alternative force was shown to damage the cells contrary to static force. • The effect of indentation of magnetic particles was compared to the one of AFM tips. • The damage was attributed to the formation of clusters of particles.

  15. (g -2 )μ, lepton flavor violation, and Z decays with leptoquarks: Correlations and future prospects

    Science.gov (United States)

    Leskow, Estefania Coluccio; D'Ambrosio, Giancarlo; Crivellin, Andreas; Müller, Dario

    2017-03-01

    The long-standing anomaly in the anomalous magnetic moment of the muon indicates the presence of chirality violating new physics contributions. A possible solution involves scalar leptoquarks with left- and right-handed couplings to the top quark. Two such representations of scalar leptoquarks exist for which the contribution to (g -2 )μ can possess an mt/mμ enhancement compared to the Standard Model. The leptoquarks also induce loop corrections to Z couplings to muons which probe as well new physics contributions which possess sources of S U (2 ) symmetry breaking and we find that this effect should be observable at future experiments as GigaZ or TLEP. Furthermore, once interactions of the leptoquark with tau leptons and electrons are present, additional correlated effects in anomalous magnetic moments, Z →ℓℓ' and ℓ→ℓ' γ, arise, which can be used to test the model and to determine the flavor structure of the couplings. We find that the two representations of leptoquarks can be distinguished also from low-energy experiments: one representation predicts constructive interference with the Standard Model in Z couplings to leptons and effects in B →K(⋆)ν ν ¯, while the other representation interferes destructively with the Standard Model in Z couplings to leptons and gives a C9=C10-like contribution to b →s ℓ+ℓ- processes.

  16. An Intelligent Approach for Dense Urban Area in existing 2G / 2.5G

    CERN Document Server

    Katiyar, Sumit; Agrawal, Prof N K

    2012-01-01

    In the prevailing scenario audio, video, data services (i.e. internet), multimedia and broadcasting etc. are being integrated. Decreasing cell size increases capacity but at the same time increases fluctuation and interference too. The intelligence approach is the only answer in developing countries where frequency and power are scarce resources. In this paper, we have tried to integrate all proven technologies in networking such as in-building network, micro zone, intelligent micro cell, deployment along city streets, tunnels, subway coverage etc. along with adaptive frequency allocation in hierarchical approach with the help of adaptive / intelligent antenna system. A-SDMA approach will further enhance spectral efficiency as well as QoS (Quality of Service). It can be proved beyond doubt that this integrated approach will convert 2G / 2.5G systems capable of handling the prevailing demand at reduced cost. In addition to it, integrated approach will save power and reduce RF pollution. In this paper we have e...

  17. Muon g - 2 through a flavor structure on soft SUSY terms

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Baez, F.V. [Universidad Autonoma de Nuevo Leon, UANL Ciudad Universitaria, FCFM, San Nicolas de los Garza, Nuevo Leon (Mexico); Gomez Bock, M. [Universidad de las Americas Puebla, UDLAP, Ex-Hacienda Sta. Catarina Martir, DAFM, Cholula, Puebla (Mexico); Mondragon, M. [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Apdo. Postal 20-364, Mexico, D.F. (Mexico)

    2016-10-15

    In this work we analyze the possibility to explain the muon anomalous magnetic moment discrepancy within theory and experiment through lepton-flavor violation processes. We propose a flavor extended MSSM by considering a hierarchical family structure for the trilinear scalar soft-supersymmetric terms of the Lagrangian, present at the SUSY breaking scale. We obtain analytical results for the rotation mass matrix, with the consequence of having non-universal slepton masses and the possibility of leptonic flavor mixing. The one-loop supersymmetric contributions to the leptonic flavor violating process τ → μγ are calculated in the physical basis, instead of using the well-known mass-insertion method. The flavor violating processes BR(l{sub i} → l{sub j}γ) are also obtained, in particular τ → μγ is well within the experimental bounds. We present the regions in parameter space where the muon g - 2 problem is either entirely solved or partially reduced through the contribution of these flavor violating processes. (orig.)

  18. Evaluation of anti-hepatocarcinoma capacity of puerarin nanosuspensions against human HepG2 cells

    Science.gov (United States)

    Meng, Xiang-Ping; Zhang, Zhen; Wang, Yi-Fei; Wang, Zhi-ping; Chen, Tong-sheng

    2017-02-01

    Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Puerarin (Pue), a major active ingredient in the traditional Chinese medicine Gegen, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Pue nanosuspension (Pue-NS) composed of Pue and poloxamer 188 was prepared by high pressure homogenization technique. The in vitro anti-hepatocarcinoma effects of Pue-NS relative to efficacy of bulk Pue were evaluated. The particle size and zeta potential of Pue-NS were 218.5 nm and -18.8 mV, respectively. MTT assay showed that Pue-NS effectively inhibited the proliferation of HepG2 cells, and the corresponding IC50 values of Pue-NS and bulk Pue were 3.39 and 5.73 μg/ml. These results suggest that the delivery of Pue-NS is a promising approach for treating tumors.

  19. Performance of the instrumentation for measuring ωa in the Muon g-2 experiment

    Science.gov (United States)

    Khaw, Kim Siang; Muon g-2 Collaboration

    2016-09-01

    The Muon g-2 experiment at Fermilab will begin data taking in 2017. The precision goal of 140 ppb requires collecting 21 times more data than the BNL E821 experiment, which resulted in the now well-known > 3 σ deviation between measurement and the Standard Model prediction. In addition the systematic uncertainties must be reduced by a factor of 3. To this end, an all-new detector and electronics instrumentation used to determine the anomalous precession frequency was designed. We report here on a recent test-beam run at SLAC that acquired realistic data from initial calorimeter calibration through fully reconstructed offline analysis. We will report on the performance of the following state-of-the-art systems: laser-based calibration network, PbF2 calorimeter with ultra-fast SiPM readout, custom 800 MSPS 12-bit digitizers, online DAQ with an active GPU processing farm, and finally art-based offline framework. The combination of a mono-energetic multi-GeV electron beam and a sophisticated fast laser firing sequence enabled data to be taken at a variety of rates under controlled conditions. These tests provided crucial information regarding the needed performance for the systematics and established the capability of the instrumentation to handle high data rate.

  20. Beam Position Reconstruction for the g2p Experiment in Hall A at Jefferson Lab

    CERN Document Server

    Zhu, Pengjia; Allison, Trent; Badman, Toby; Camsonne, Alexandre; Chen, Jian-ping; Cummings, Melissa; Gu, Chao; Huang, Min; Liu, Jie; Musson, John; Slifer, Karl; Sulkosky, Vincent; Ye, Yunxiu; Zhang, Jixie; Zielinski, Ryan

    2015-01-01

    Beam-line equipment was upgraded for experiment E08-027 (g2p) in Hall A at Jefferson Lab. Two beam position monitors (BPMs) were necessary to measure the beam position and angle at the target. A new BPM receiver was designed and built to handle the low beam currents (50-100 nA) used for this experiment. Two new super-harps were installed for calibrating the BPMs. In addition to the existing fast raster system, a slow raster system was installed. Before and during the experiment, these new devices were tested and debugged, and their performance was also evaluated. In order to achieve the required accuracy (1-2 mm in position and 1-2 mrad in angle at the target location), the data of the BPMs and harps were carefully analyzed, as well as reconstructing the beam position and angle event by event at the target location. The calculated beam position will be used in the data analysis to accurately determine the kinematics for each event.

  1. Hydrological Excitations of Polar Motion Derived from Different Variables of Fgoals - g2 Climate Model

    Science.gov (United States)

    Winska, M.

    2016-12-01

    The hydrological contribution to decadal, inter-annual and multi-annual suppress polar motion derived from climate model as well as from GRACE (Gravity Recovery and Climate Experiment) data is discussed here for the period 2002.3-2016.0. The data set used here are Earth Orientation Parameters Combined 04 (EOP C04), Flexible Global Ocean-Atmosphere-Land System Model: Grid-point Version 2 (FGOAL-g2) and Global Land Data Assimilation System (GLDAS) climate models and GRACE CSR RL05 data for polar motion, hydrological and gravimetric excitation, respectively. Several Hydrological Angular Momentum (HAM) functions are calculated here from the selected variables: precipitation, evaporation, runoff, soil moisture, accumulated snow of the FGOALS and GLDAS climate models as well as from the global mass change fields from GRACE data provided by the International Earth Rotation and Reference System Service (IERS) Global Geophysical Fluids Center (GGFC). The contribution of different HAM excitation functions to achieve the full agreement between geodetic observations and geophysical excitation functions of polar motion is studied here.

  2. Detection of polarized continuum emission of the Dusty S-cluster Object (DSO/G2)

    CERN Document Server

    Shahzamanian, Banafsheh; Valencia-S., Monica; Peissker, Florian; Eckart, Andreas; Sabha, Nadeen; Parsa, Marzieh

    2016-01-01

    A peculiar source in the Galactic center known as the Dusty S-cluster Object (DSO/G2) moves on a highly eccentric orbit around the supermassive black hole with the pericenter passage in the spring of 2014. Its nature has been uncertain mainly because of the lack of any information about its intrinsic geometry. For the first time, we use near-infrared polarimetric imaging data to obtain constraints about the geometrical properties of the DSO. We find out that DSO is an intrinsically polarized source, based on the significance analysis of polarization parameters, with the degree of the polarization of $\\sim 30\\%$ and an alternating polarization angle as it approaches the position of Sgr A*. Since the DSO exhibits a near-infrared excess of $K_{\\rm s}-L'>3$ and remains rather compact in emission-line maps, its main characteristics may be explained with the model of a pre-main-sequence star embedded in a non-spherical dusty envelope.

  3. Further identification of endogenous gibberellins in the shoots of pea, line G2

    Energy Technology Data Exchange (ETDEWEB)

    Halinska, A.; Davies, P.J.; Lee, J.W.; Zhu, Yuxian (Cornell Univ., Ithaca, NY (USA))

    1989-12-01

    To interpret the metabolism of radiolabeled gibberellins A{sub 12}-aldehyde and A{sub 12} in shoots of pea (Pisum sativum L.), the identity of the radiolabeled peaks has to be determined and the endogenous presence of the gibberellins demonstrated. High specific activity ({sup 14}C)GA{sub 12} and ({sup 14}C)GA{sub 12}-aldehyde were synthesized using a pumpkin endosperm enzyme preparation, and purified by high performance liquid chromatography (HPLC). ({sup 14}C)GA{sub 12} was supplied to upper shoots of pea, line G2, to produce radiolabeled metabolites on the 13-OH pathway. Endogenous compounds copurifying with the ({sup 14}C)GAs on HPLC were analyzed by gas chromatography-mass spectrometry. The endogenous presence of GA{sub 53}, GA{sub 44}, GA{sub 19} and GA{sub 20} was demonstrated and their HPLC peak identity ascertained. The {sup 14}C was progressively diluted in GAs further down the pathway, proportional to the levels found in the tissue and inversely proportional to the speed of metabolism, ranging from 63% in GA{sub 53} to 4% in GA{sub 20}. Calculated levels of GA{sub 20}, GA{sub 19}, GA{sub 44}, and GA{sub 53} were 42, 8, 10, and 0.5 nanograms/gram, respectively.

  4. Histone deacetylase inhibitors promote glioma cell death by G2 checkpoint abrogation leading to mitotic catastrophe.

    Science.gov (United States)

    Cornago, M; Garcia-Alberich, C; Blasco-Angulo, N; Vall-Llaura, N; Nager, M; Herreros, J; Comella, J X; Sanchis, D; Llovera, M

    2014-10-02

    Glioblastoma multiforme is resistant to conventional anti-tumoral treatments due to its infiltrative nature and capability of relapse; therefore, research efforts focus on characterizing gliomagenesis and identifying molecular targets useful on therapy. New therapeutic strategies are being tested in patients, such as Histone deacetylase inhibitors (HDACi) either alone or in combination with other therapies. Here two HDACi included in clinical trials have been tested, suberanilohydroxamic acid (SAHA) and valproic acid (VPA), to characterize their effects on glioma cell growth in vitro and to determine the molecular changes that promote cancer cell death. We found that both HDACi reduce glioma cell viability, proliferation and clonogenicity. They have multiple effects, such as inducing the production of reactive oxygen species (ROS) and activating the mitochondrial apoptotic pathway, nevertheless cell death is not prevented by the pan-caspase inhibitor Q-VD-OPh. Importantly, we found that HDACi alter cell cycle progression by decreasing the expression of G2 checkpoint kinases Wee1 and checkpoint kinase 1 (Chk1). In addition, HDACi reduce the expression of proteins involved in DNA repair (Rad51), mitotic spindle formation (TPX2) and chromosome segregation (Survivin) in glioma cells and in human glioblastoma multiforme primary cultures. Therefore, HDACi treatment causes glioma cell entry into mitosis before DNA damage could be repaired and to the formation of an aberrant mitotic spindle that results in glioma cell death through mitotic catastrophe-induced apoptosis.

  5. 125 GeV Higgs boson mass and muon g-2 in 5D MSSM

    CERN Document Server

    Okada, Nobuchika

    2016-01-01

    In the MSSM, the tension between the observed Higgs boson mass and the experimental result of the muon $g-2$ measurement requires a large mass splitting between stops and smuons/charginos/neutralinos. We consider a 5-dimensional (5D) framework of the MSSM with the Randall-Sundrum warped background metric, and show that such a mass hierarchy is naturally achieved in terms of geometry. In our setup, the supersymmetry is broken at the ultraviolet (UV) brane, while all the MSSM multiplets reside in the 5D bulk. An appropriate choice of the bulk mass parameters for the MSSM matter multiplets can naturally realize the sparticle mass hierarchy desired to resolve the tension. Gravitino is localized at the UV brane and hence becomes very heavy, while the gauginos spreading over the bulk acquire their masses suppressed by the 5th dimensional volume. As a result, the LSP neutralino is a candidate for the dark matter as usual in the MSSM. In addition to reproducing the SM-like Higgs boson mass of around 125 GeV and the m...

  6. G2 and Sgr A*: A Cosmic Fizzle At The Galactic Center

    CERN Document Server

    Morsony, Brian; Workman, Jared; Yoon, DooSoo

    2015-01-01

    We carry out a series of simulations of G2-type clouds interacting with the black hole Sgr A* at the galactic center. We determine that the accretion rate from the gas cloud onto Sgr A* for a range of simulation parameters, such as cloud structure, background structure, background density, grid resolution, and accretion radius. Regardless of the numerical considerations, the amount of cloud material accreted is small, both compared to the total cloud mass and the normal background accretion rate. The accretion rate will remain small for at least 30 years after periapsis. We also model Br-gamma, bolometric, and X-ray emission from the cloud with a variety of density profiles, and compare to observational data. In simulations, the bolometric and X-ray luminosity have a peak in luminosity lasting from about 1 year before to 1 year after periapsis, a feature not detected in observations. Simulated Br-gamma emission remains nearly flat with a small peak 1 month to 1 year before periapsis, depending on how centrall...

  7. Antioxidant potential of herbs extracts and impact on HepG2 cells viability

    Directory of Open Access Journals (Sweden)

    Anna Gramza-Michałowska

    2008-12-01

    Full Text Available Mercury poisoning is responsible for inducing serious adverse effects in living organisms. One of protection factors could be substances proven to possess high antioxidant and metal chelating activity – plant polyphenols. There are many sources of polyphenols in plant kingdom but the most interesting for food industry could be widely consumed herbs. Aim of the research was to evaluate antioxidative potential of selected plant extracts and its influence on HepG2 cells in different conditions. Ethanolic herbs extracts were characterised by total polyphenol content. Antioxidant activity was estimated with use of DPPH• and ABTS+• radicals scavenging methods and FRAP. Research included cells viability estimation by the MTT assay and cells exposition to HgCl2, chemical agent inducing cell death. Analysis of herbs extracts antioxidative activity showed best potential represented thyme and marjoram, highest FRAP was evaluated in samples with mint and marjoram extracts. On the basis of received results it was found that examined plant extracts showed weak protection against Hg presence in examined cells environment.

  8. Cytotoxicity evaluation of symmetrically branched glycerol trimer in human hepatocellular carcinoma HepG2 cells.

    Science.gov (United States)

    Miyamoto, Licht; Watanabe, Masashi; Kono, Mai; Matsushita, Tsuyoshi; Hattori, Hatsuhiko; Ishizawa, Keisuke; Nemoto, Hisao; Tsuchiya, Koichiro

    2012-01-01

    An appropriate balance between lipophilicity and hydrophilicity is necessary for pharmaceuticals to achieve fine Absorption, Distribution, Metabolism and Excretion (ADME) properties including absorption and distribution, in particular. We have designed and proposed symmetrically branched oligoglycerols (BGL) as an alternative approach to improve the lipophilic-hydrophilic balance. We have previously shown that stability in circulation and water-solubility of such molecules as proteins, liposomes and hydrophobic compounds are much improved by conjugation to BGL. Albeit these successful applications of BGL, little was known whether BGL could be used in safety. Thus we conducted evaluation of the cytotoxicity of a representative BGL, symmetrically branched glycerol trimer (BGL003) in the cultured cells to clarify its biological safeness. Here we demonstrate that water-solubility of an extremely hydrophobic agent, fenofibrate was more than 2,000-fold improved just by conjugated with BGL003. BGL003 did not exhibit any significant cytotoxicity in human hepatocarcinoma HepG2 cells. Thus BGL003 should be safe and suitable strategy to endow hydrophobic molecules with much hydrophilicity.

  9. High-LET radiation-induced aberrations in prematurely condensed G2 chromosomes of human fibroblasts

    Science.gov (United States)

    Kawata, T.; Gotoh, E.; Durante, M.; Wu, H.; George, K.; Furusawa, Y.; Cucinotta, F. A.; Dicello, J. F. (Principal Investigator)

    2000-01-01

    PURPOSE: To determine the number of initial chromatid breaks induced by low- or high-LET irradiations, and to compare the kinetics of chromatid break rejoining for radiations of different quality. MATERIAL AND METHODS: Exponentially growing human fibroblast cells AG1522 were irradiated with gamma-rays, energetic carbon (290MeV/u), silicon (490MeV/u) and iron (200 and 600 MeV/u). Chromosomes were prematurely condensed using calyculin A. Chromatid breaks and exchanges in G2 cells were scored. PCC were collected after several post-irradiation incubation times, ranging from 5 to 600 min. RESULTS: The kinetics of chromatid break rejoining following low- or high-LET irradiation consisted of two exponential components representing a rapid and a slow time constant. Chromatid breaks decreased rapidly during the first 10min after exposure, then continued to decrease at a slower rate. The rejoining kinetics were similar for exposure to each type of radiation. Chromatid exchanges were also formed quickly. Compared to low-LET radiation, isochromatid breaks were produced more frequently and the proportion of unrejoined breaks was higher for high-LET radiation. CONCLUSIONS: Compared with gamma-rays, isochromatid breaks were observed more frequently in high-LET irradiated samples, suggesting that an increase in isochromatid breaks is a signature of high-LET radiation exposure.

  10. 3D Moving-Mesh Simulations of Galactic Center Cloud G2

    CERN Document Server

    Anninos, Peter; Wilson, Julia; Murray, Stephen D

    2012-01-01

    Using three-dimensional, moving-mesh simulations, we investigate the future evolution of the recently discovered gas cloud G2 traveling through the galactic center. We consider the case of a spherical cloud initially in pressure equilibrium with the background. Our suite of simulations explores the following parameters: the equation of state, radial profiles of the background gas, and start times for the evolution. Our primary focus is on how the fate of this cloud will affect the future activity of Sgr A*. From our simulations we expect an average feeding rate in the range of 5-19 \\times 10^{-8} solar masses per year beginning in 2013 and lasting for at least 7 years (our simulations stop in year 2020). The accretion varies by less than a factor of three on timescales <1 month, and shows no more than a factor of 10 difference between the maximum and minimum. These rates are comparable to the current estimated accretion rate in the immediate vicinity of Sgr A*, although they represent only a small (<5%)...

  11. Update on 3D Moving Mesh Simulations of Galactic Center Cloud G2

    CERN Document Server

    Fragile, P Chris; Murray, Stephen D

    2014-01-01

    Using three-dimensional, moving-mesh simulations, we investigate the future evolution of the recently discovered gas cloud G2 traveling through the galactic center. From our simulations we expect an average feeding rate onto Sgr A* in the range of $(5-19) \\times 10^{-8} M_\\odot\\mathrm{~yr}^{-1}$ beginning in 2014. This accretion varies by less than a factor of three on timescales of about 1 month, and shows no more than a factor of 10 difference between the maximum and minimum observed rates within any given model. These rates are comparable to the current estimated accretion rate in the immediate vicinity of Sgr A*, although they represent only a small (<10%) increase over the current expected feeding rate at the effective inner boundary of our simulations $(r_\\mathrm{acc} = 750 R_S \\sim 10^{15} \\mathrm{cm})$. We also explore multiple possible equations of state to describe the gas. In examining the Br-$\\gamma$ light curves produced from our simulations, we find that all of our isothermal models predict s...

  12. Reconciling $(g-2)_\\mu$ and charged lepton flavour violating processes through a doubly charged scalar

    CERN Document Server

    Chakrabortty, Joydeep; Mondal, Subhadeep; Srivastava, Tripurari

    2015-01-01

    In this work, we investigate the phenomenological consequences of a doubly charged scalar which may belong to different uncoloured scalar multiplets. This doubly charged scalar couples to the charged leptons as well as gauge bosons, which we parametrize in a model independent way. Restricting ourselves in the regime of conserved charged-parity (CP), we assume only a few non-zero Yukawa couplings ($y_{\\mu \\ell}$, where $\\ell=e,\\mu,\\tau$) between the doubly charged scalar and the charged leptons. Our choices allow the doubly charged scalar to impinge low-energy processes like anomalous magnetic moment of muon and a few possible charged lepton flavour violating (CLFV) processes. These same Yukawa couplings are also instrumental in producing same-sign di-lepton signatures at the LHC. In this article we examine the impact of individual contributions from the diagonal and off-diagonal Yukawa couplings in the light of muon $(g-2)$ excess. Subsequently, we use the derived information to inquire the possible CLFV proc...

  13. Leading-order hadronic contribution to the electron and muon g-2

    CERN Document Server

    Jegerlehner, Fred

    2015-01-01

    I present a new data driven update of the hadronic vacuum polarization effects for the muon and the electron g-2. For the leading order contributions I find a_mu[LO VP]=(688.57 +/-4.28)[688.91+/-3.52] 10^{-10} based on e+e- data [incl. tau data], a_mu[VP NLO]= (-9.92+/- 0.10) 10^{-10} and a_mu[VP NNLO]= (1.23+/- 0.01) 10^{-10} for the muon, and a_e[VP LO]=(185.11+/- 1.24) 10^{-14}, a_e[VP NLO]=(-22.15+/- 0.16) 10^{-14} and a_e[VP NNLO]=(2.80+/- 0.02) 10^{-14} for the electron. A problem with vacuum polarization undressing of cross-sections (time-like region) is addressed. I also add a comment on properly including axial mesons in the hadronic light-by-light scattering contribution. My estimate here reads a_mu[a_1,f_1',f_1] = ({ 7.51 +/- 2.71}) 10^{-11}. With these updates a_mu [exp]-a_mu [the]=(31.0+/- 8.2) 10^{-10} a 3.8 sigma deviation, while a_e [exp]-a_e [the]=(-1.14+/- 0.82) 10^{-12} shows no significant deviation.

  14. Data Acquisition for the New Muon $g$-$2$ Experiment at Fermilab

    CERN Document Server

    Gohn, Wesley

    2015-01-01

    A new measurement of the anomalous magnetic moment of the muon, $a_{\\mu} \\equiv (g-2)/2$, will be performed at the Fermi National Accelerator Laboratory. The most recent measurement, performed at Brookhaven National Laboratory and completed in 2001, shows a 3.3-3.6 standard deviation discrepancy with the Standard Model predictions for $a_\\mu$. The new measurement will accumulate 21 times those statistics, measuring $a_\\mu$ to 140 ppb and reducing the uncertainty by a factor of 4. The data acquisition system for this experiment must have the ability to record deadtime-free records from 700 $\\mu$s muon spills at a raw data rate of 18 GB per second. Data will be collected using 1296 channels of $\\mu$TCA-based 800 MSPS, 12 bit waveform digitizers and processed in a layered array of networked commodity processors with 24 GPUs working in parallel to perform a fast recording and processing of detector signals during the spill. The system will be controlled using the MIDAS data acquisition software package. The descr...

  15. A Conserved Myc Protein Domain, MBIV, Regulates DNA Binding, Apoptosis, Transformation, and G2 Arrest†

    Science.gov (United States)

    Cowling, Victoria H.; Chandriani, Sanjay; Whitfield, Michael L.; Cole, Michael D.

    2006-01-01

    The myc family of oncogenes is well conserved throughout evolution. Here we present the characterization of a domain conserved in c-, N-, and L-Myc from fish to humans, N-Myc317-337, designated Myc box IV (MBIV). A deletion of this domain leads to a defect in Myc-induced apoptosis and in some transformation assays but not in cell proliferation. Unlike other Myc mutants, MycΔMBIV is not a simple loss-of-function mutant because it is hyperactive for G2 arrest in primary cells. Microarray analysis of genes regulated by N-MycΔMBIV reveals that it is weakened for transactivation and repression but not nearly as defective as N-MycΔMBII. Although the mutated region is not part of the previously defined DNA binding domain, we find that N-MycΔMBIV has a significantly lower affinity for DNA than the wild-type protein in vitro. Furthermore, chromatin immunoprecipitation shows reduced binding of N-MycΔMBIV to some target genes in vivo, which correlates with the defect in transactivation. Thus, this conserved domain has an unexpected role in Myc DNA binding activity. These data also provide a novel separation of Myc functions linked to the modulation of DNA binding activity. PMID:16705173

  16. Bile acids reduce endocytosis of high-density lipoprotein (HDL) in HepG2 cells.

    Science.gov (United States)

    Röhrl, Clemens; Eigner, Karin; Fruhwürth, Stefanie; Stangl, Herbert

    2014-01-01

    High-density lipoprotein (HDL) transports lipids to hepatic cells and the majority of HDL-associated cholesterol is destined for biliary excretion. Cholesterol is excreted into the bile directly or after conversion to bile acids, which are also present in the plasma as they are effectively reabsorbed through the enterohepatic cycle. Here, we provide evidence that bile acids affect HDL endocytosis. Using fluorescent and radiolabeled HDL, we show that HDL endocytosis was reduced in the presence of high concentrations of taurocholate, a natural non-cell-permeable bile acid, in human hepatic HepG2 and HuH7 cells. In contrast, selective cholesteryl-ester (CE) uptake was increased. Taurocholate exerted these effects extracellularly and independently of HDL modification, cell membrane perturbation or blocking of endocytic trafficking. Instead, this reduction of endocytosis and increase in selective uptake was dependent on SR-BI. In addition, cell-permeable bile acids reduced HDL endocytosis by farnesoid X receptor (FXR) activation: chenodeoxycholate and the non-steroidal FXR agonist GW4064 reduced HDL endocytosis, whereas selective CE uptake was unaltered. Reduced HDL endocytosis by FXR activation was independent of SR-BI and was likely mediated by impaired expression of the scavenger receptor cluster of differentiation 36 (CD36). Taken together we have shown that bile acids reduce HDL endocytosis by transcriptional and non-transcriptional mechanisms. Further, we suggest that HDL endocytosis and selective lipid uptake are not necessarily tightly linked to each other.

  17. Effect of cyclin G2 on proliferative ability of prostate cancer PC-3 cell.

    Science.gov (United States)

    Cui, D W; Cheng, Y J; Jing, S W; Sun, G G

    2014-04-01

    This study aimed to analyze the expression, clinical significance of cyclin G2 (CCNG2) in prostate carcinoma, and the biological effect in its cell line by CCNG2 overexpression. Immunohistochemistry and Western blot were used to analyze CCNG2 protein expression in 85 cases of prostate cancer and normal tissues to study the relationship between CCNG2 expression and clinical factors. CCNG2 lentiviral vector and empty vector were, respectively, transfected into prostate cancer PC-3 cell line. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the mRNA level and protein of CCNG2. MTT assay and cell cycle were also conducted as to the influence of the upregulated expression of CCNG2 that might be found on PC-3 cells biological effect. The level of CCNG2 protein expression was found to be significantly lower in prostate cancer tissue than normal tissues (P size (P lymph node metastasis, clinic stage, and Gleason score (P prostate cancer and correlated significantly with lymph node metastasis, clinic stage, and Gleason score, suggesting that CCNG2 may play important roles as a negative regulator to prostate cancer cell.

  18. Beam position reconstruction for the g2p experiment in Hall A at Jefferson lab

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Pengjia, E-mail: pzhu@jlab.org [University of Science and Technology of China, Hefei, Anhui 230026 (China); Allada, Kalyan [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Massachusetts Institute of Technology, MA 02139 (United States); Allison, Trent [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Badman, Toby [University of New Hampshire, Durham, NH 03824 (United States); Camsonne, Alexandre; Chen, Jian-ping [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Cummings, Melissa [College of William & Mary, Williamsburg, VA 23187 (United States); Gu, Chao [University of Virginia, Charlottesville, VA 22904 (United States); Huang, Min [Duke University, Durham, NC 27708 (United States); Liu, Jie [University of Virginia, Charlottesville, VA 22904 (United States); Musson, John [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Slifer, Karl [University of New Hampshire, Durham, NH 03824 (United States); Sulkosky, Vincent [University of Virginia, Charlottesville, VA 22904 (United States); Massachusetts Institute of Technology, MA 02139 (United States); Ye, Yunxiu [University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhang, Jixie [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); University of Virginia, Charlottesville, VA 22904 (United States); Zielinski, Ryan [University of New Hampshire, Durham, NH 03824 (United States)

    2016-02-01

    Beam-line equipment was upgraded for experiment E08-027 (g2p) in Hall A at Jefferson Lab. Two beam position monitors (BPMs) were necessary to measure the beam position and angle at the target. A new BPM receiver was designed and built to handle the low beam currents (50–100 nA) used for this experiment. Two new super-harps were installed for calibrating the BPMs. In addition to the existing fast raster system, a slow raster system was installed. Before and during the experiment, these new devices were tested and debugged, and their performance was also evaluated. In order to achieve the required accuracy (1–2 mm in position and 1–2 mrad in angle at the target location), the data of the BPMs and harps were carefully analyzed, as well as reconstructing the beam position and angle event by event at the target location. The calculated beam position will be used in the data analysis to accurately determine the kinematics for each event.

  19. Muon g-2, 125 GeV Higgs and Neutralino Dark Matter in sMSSM

    CERN Document Server

    Babu, K S; Shafi, Qaisar; Un, Cem Salih

    2014-01-01

    We discuss the sparticle (and Higgs) spectrum in a class of flavor symmetry-based minimal supersymmetric standard models, referred to here as sMSSM. In this framework the SUSY breaking Lagrangian takes the most general form consistent with a grand unified symmetry such as SO(10) and a non-Abelian flavor symmetry acting on the three families with either a 2+1 or a 3 family assignment. Models based on gauged SU(2) and SO(3) flavor symmetry, as well as non-Abelian discrete symmetries such as S_3 and A_4, have been suggested which fall into this category. These models describe supersymmetry breaking in terms of seven phenomenological parameters. The soft supersymmetry breaking masses at M_GUT of all sfermions of the first two families are equal in sMSSM, which differ in general from the corresponding third family mass. In such a framework we show that the muon g-2 anomaly, the observed Higgs boson mass of ~ 125 GeV, and the observed relic neutralino dark matter abundance can be simultaneously accommodated. The re...

  20. Does Resveratrol Improve Insulin Signalling in HepG2 Cells?

    Science.gov (United States)

    Norouzzadeh, Marjan; Amiri, Fatemehsadat; Saboor-Yaraghi, Ali Akbar; Shemirani, Farnoosh; Kalikias, Yas; Sharifi, Loghman; Seyyedsalehi, Monireh Sadat; Mahmoudi, Maryam

    2017-04-01

    Diabetes mellitus is a common metabolic disorder with high global prevalence. It is characterized by a decrease in insulin secretion or a decrease in insulin sensitivity or both. The aim of the present study was to investigate the effects of resveratrol treatment on the expression of the genes involved in insulin signalling cascade, such as Forkhead box protein O1 (FoxO1), 3-phosphoinositide-dependent protein kinase 1 (PDPK1) and mammalian target of rapamycin (mTOR). HepG2 cells were cultured in serum-free medium with high concentrations of glucose and insulin and then were treated with resveratrol (5, 10 and 20 µM) for 24 and 48 hours. Complementary deoxyribonucleic acids (cDNAs) were synthesized followed by RNA extraction. Real-time quantitative reverse transcription polymerase chain reaction was used to analyze the expression of FoxO1, PDPK1 and mTOR. Resveratrol increased the expression of PDPK1, mTOR and FoxO1. No significant difference was seen among differing dosages of resveratrol, but treatments for 48 hours exerted the greatest effectiveness. Our results were consistent with other studies showing the beneficial effects of resveratrol on diabetes. However, considering the effects of resveratrol in increasing FoxO1 and gluconeogenic gene expression, long-term usage of resveratrol should be investigated in greater depth in future studies. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  1. Cholesterol-lowing effect of taurine in HepG2 cell.

    Science.gov (United States)

    Guo, Junxia; Gao, Ya; Cao, Xuelian; Zhang, Jing; Chen, Wen

    2017-03-16

    A number of studies indicate that taurine promotes cholesterol conversion to bile acids by upregulating CYP7A1 gene expression. Few in vitro studies are concerned the concentration change of cholesterol and its product of bile acids, and the molecular mechanism of CYP7A1 induction by taurine. The levels of intracellular total cholesterol (TC), free cholesterol (FC), cholesterol ester (EC), total bile acids (TBA) and medium TBA were determined after HepG2 cells were cultured for 24/48 h in DMEM supplemented with taurine at the final concentrations of 1/10/20 mM respectively. The protein expressions of CYP7A1, MEK1/2, c-Jun, p-c-Jun and HNF-4α were detected. Taurine significantly reduced cellular TC and FC in dose -and time-dependent ways, and obviously increased intracellular/medium TBA and CYP7A1 expressions. There was no change in c-Jun expression, but the protein expressions of MEK1/2 and p-c-Jun were increased at 24 h and inhibited at 48 h by 20 mM taurine while HNF4α was induced after both of the 24 h and 48 h treatment. Taurine could enhance CYP7A1 expression by inducing HNF4α and inhibiting MEK1/2 and p-c-Jun expressions to promote intracellular cholesterol metabolism.

  2. Determinants of mitotic catastrophe on abrogation of the G2 DNA damage checkpoint by UCN-01.

    Science.gov (United States)

    On, Kin Fan; Chen, Yue; Ma, Hoi Tang; Chow, Jeremy P H; Poon, Randy Y C

    2011-05-01

    Genotoxic stress such as ionizing radiation halts entry into mitosis by activation of the G(2) DNA damage checkpoint. The CHK1 inhibitor 7-hydroxystaurosporine (UCN-01) can bypass the checkpoint and induce unscheduled mitosis in irradiated cells. Precisely, how cells behave following checkpoint abrogation remains to be defined. In this study, we tracked the fates of individual cells after checkpoint abrogation, focusing in particular on whether they undergo mitotic catastrophe. Surprisingly, while a subset of UCN-01-treated cells were immediately eliminated during the first mitosis after checkpoint abrogation, about half remained viable and progressed into G(1). Both the delay of mitotic entry and the level of mitotic catastrophe were dependent on the dose of radiation. Although the level of mitotic catastrophe was specific for different cell lines, it could be promoted by extending the mitosis. In supporting this idea, weakening of the spindle-assembly checkpoint, by either depleting MAD2 or overexpressing the MAD2-binding protein p31(comet), suppressed mitotic catastrophe. Conversely, delaying of mitotic exit by depleting either p31(comet) or CDC20 tipped the balance toward mitotic catastrophe. These results underscore the interplay between the level of DNA damage and the effectiveness of the spindle-assembly checkpoint in determining whether checkpoint-abrogated cells are eliminated during mitosis.

  3. Effect of caffeine and adenosine on G2 repair: mitotic delay and chromosome damage.

    Science.gov (United States)

    González-Fernández, A; Hernández, P; López-Sáez, J F

    1985-04-01

    Proliferating plant cells treated during the late S period with 5-aminouracil (AU), give the typical response that DNA-damaging agents induce, characterized by: an important mitotic delay, and a potentiation of the chromosome damage by caffeine post-treatment. The study of labelled prophases, after a tritiated thymidine pulse, allowed evaluation of the mitotic delay induced by AU as well as its reversion by caffeine, while chromosome damage was estimated by the percentage of anaphases and telophases showing chromosomal aberrations. Post-treatment with adenosine alone has shown no effect on mitotic delay or chromosomal damage. However, when cells after AU were incubated in caffeine plus adenosine, the chromosome damage potentiation was abolished without affecting the caffeine action on mitotic delay. As a consequence, we postulate that caffeine could have two effects on G2 cells with damaged DNA: the first, to cancel their mitotic delay and the second to inhibit some DNA-repair pathway(s). Only this last effect could be reversed by adenosine.

  4. Simulation and Track Reconstruction Techniques for the J-PARC muon g-2 experiment

    Science.gov (United States)

    Tsilias, Paschalis; Lee, Myeong Jae

    2017-03-01

    The Muon g-2/EDM proposed experiment at J-PARC is a promising and innovative attempt at the field of Precision Physics. The sensitivity goal of 0.1 ppm will test the limits of our current understanding, and may probe for Beyond the Standard Model observations. This paper seeks out to investigate the computational techniques required by the experiment. The GEANT4 [1] framework was used to simulate the detector setup, according to the experiment's Conceptual Design Report (CDR) [2]. This allowed to observe the event hierarchy in different energies, generate signal hit data, and construct an event-selection algorithm. ROOT and GDML enabled us to use the geometry and parsed output data in a platform-independent way. Using techniques pertaining to Machine Learning and Image Feature extraction, such as the Canny Edge detection and the Hough Transform, we were able to construct a generic representation of `track families' from each event category. Finally, the modular GENFIT2 [3] framework was used to implement the Kalman Filter [4] along with an Deterministic Annealing Filter (DAF) [5] and the Runge-Kutta stepper to reconstruct tracks from a few digitized, smeared singular event data.

  5. Ovothiol Isolated from Sea Urchin Oocytes Induces Autophagy in the Hep-G2 Cell Line

    Directory of Open Access Journals (Sweden)

    Gian Luigi Russo

    2014-07-01

    Full Text Available Ovothiols are histidine-derived thiols isolated from sea urchin eggs, where they play a key role in the protection of cells toward the oxidative burst associated with fertilization by controlling the cellular redox balance and recycling oxidized glutathione. In this study, we show that treatment of a human liver carcinoma cell line, Hep-G2, with ovothiol A, isolated from Paracentrotus lividus oocytes, results in a decrease of cell proliferation in a dose-dependent manner. The activation of an autophagic process is revealed by phase contrast and fluorescence microscopy, together with the expression of the specific autophagic molecular markers, LC3 II and Beclin-1. The effect of ovothiol is not due to its antioxidant capacity or to hydrogen peroxide generation. The concentration of ovothiol A in the culture media, as monitored by HPLC analysis, decreased by about 24% within 30 min from treatment. The proliferation of normal human embryonic lung cells is not affected by ovothiol A. These results hint at ovothiol as a promising bioactive molecule from marine organisms able to inhibit cell proliferation in cancer cells.

  6. Differential expression of several drug transporter genes in HepG2 and Huh-7 cell lines.

    Science.gov (United States)

    Louisa, Melva; Suyatna, Frans D; Wanandi, Septelia Inawati; Asih, Puji Budi Setia; Syafruddin, Din

    2016-01-01

    Cell culture techniques have many advantages for investigation of drug transport to target organ like liver. HepG2 and Huh-7 are two cell lines available from hepatoma that can be used as a model for hepatic drug transport. The present study is aimed to analyze the expression level of several drug transporter genes in two hepatoma cell lines, HepG2 and Huh-7 and their response to inhibitors. This is an in vitro study using HepG2 and Huh-7 cells. The expression level of the following drug transporter genes was quantified: P-glycoprotein/multidrug resistance protein 1, Organic Anionic Transporter Protein 1B1 (OATP1B1) and Organic Cationic Transporter-1 (OCT1). Ribonucleic acid was extracted from the cells using Tripure isolation reagent, then gene expression level of the transporters is quantified using Applied Biosystems quantitative reverse transcriptase polymerase chain reaction. Verapamil (P-glycoprotein inhibitor), nelfinavir (OATP1B1 inhibitor), quinidine (OCT1 inhibitor) were used to differentiate the inhibitory properties of these agents to the transporter expressions in HepG2 and Huh-7 cells. Huh-7 shows a higher level of P-glycoprotein, OATP1B1 and OCT1 expressions compared with those of HepG2. Verapamil reduces the expressions of P-glycoprotein in HepG2 and Huh-7; nelfinavir reduces the expression of OATP1B1 in HepG2 and Huh-7; while quinidine reduces the OCT1 gene expressions in HepG2, but not in Huh-7 cells. This study indicates that HepG2 might be a more suitable in vitro model than Huh-7 to study drug transport in hepatocytes involving drug transporters.

  7. Verbesina encelioides: cytotoxicity, cell cycle arrest, and oxidative DNA damage in human liver cancer (HepG2) cell line.

    Science.gov (United States)

    Al-Oqail, Mai M; Siddiqui, Maqsood A; Al-Sheddi, Ebtesam S; Saquib, Quaiser; Musarrat, Javed; Al-Khedhairy, Abdulaziz A; Farshori, Nida N

    2016-05-10

    Cancer is a major health problem and exploiting natural products have been one of the most successful methods to combat this disease. Verbesina encelioides is a notorious weed with various pharmacological properties. The aim of the present investigation was to screen the anticancer potential of V. encelioides extract against human lung cancer (A-549), breast cancer (MCF-7), and liver cancer (HepG2) cell lines. A-549, MCF-7, and HepG2 cells were exposed to various concentrations of (10-1000 μg/ml) of V. encelioides for 24 h. Further, cytotoxic concentrations (250, 500, and 1000 μg/ml) of V. encelioides induced oxidative stress (GSH and LPO), reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest, and DNA damage in HepG2 cells were studied. The exposure of cells to 10-1000 μg/ml of extract for 24 h, revealed the concentrations 250-1000 μg/ml was cytotoxic against MCF-7 and HepG2 cells, but not against A-549 cells. Moreover, the extract showed higher decrease in the cell viability against HepG2 cells than MCF-7 cells. Therefore, HepG2 cells were selected for further studies viz. oxidative stress (GSH and LPO), reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest, and DNA damage. The results revealed differential anticancer activity of V. encelioides against A-549, MCF-7 and HepG2 cells. A significant induction of oxidative stress, ROS generation, and MMP levels was observed in HepG2 cells. The cell cycle analysis and comet assay showed that V. encelioides significantly induced G2/M arrests and DNA damage. These results indicate that V. encelioides possess substantial cytotoxic potential and may warrant further investigation to develop potential anticancer agent.

  8. 龙葵碱对人肝癌HepG2细胞N-乙酰基转移酶活性的影响%Effect of solanine on N-acetyltransferase activity in HepG2 cell

    Institute of Scientific and Technical Information of China (English)

    高世勇; 季字彬

    2008-01-01

    目的 探讨龙葵碱对HepG2细胞Ⅳ-乙酰基转移酶(NAT)活性的影响.方法 采用HPLC方法,以2-氨基芴(2-AF)为底物,以2-AF被NAT乙酰化为2-乙酰氨基芴(2-AAF)的量来反应NAT的活性.结果 龙葵碱能显著降低HepG2完整细胞NAT的活性;龙葵碱能够降低HepG2细胞质内NAT的活性,作用具有剂量依赖性.结论 龙葵碱通过抑制HepG2细胞NAT的活性发挥细胞毒作用.

  9. 76 FR 70336 - Airworthiness Directives; Rolls-Royce plc RB211-524G2-19; -524G2-T-19; -524G3-19; -524G3-T-19...

    Science.gov (United States)

    2011-11-14

    ... plc RB211-524G2-19; -524G2- T-19; -524G3-19; -524G3-T-19; 524H2-19; -524H2-T-19; -524H-36; and - 524H..., 2011. The Director of the Federal Register approved the incorporation by reference of Rolls-Royce plc... Information Rolls-Royce plc has issued Rolls-Royce plc Alert Service Bulletin No. RB.211-73-AG054, Revision...

  10. THE EFFECTS OF 3-BROMOPYRUVATE ON THE PROLIFERATION AND APOPTOSIS IN HepG-2 CELL LINE%3-溴丙酮酸对人肝癌HepG-2细胞增殖和凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    张海丽; 曾常茜; 郑学仿

    2010-01-01

    目的:通过3-溴丙酮酸作用于HepG-2细胞,观察3-溴丙酮酸对HepG-2细胞增殖和凋亡的影响.方法:MTT法检测细胞增殖,倒置显微镜和透射电镜观察细胞形态,流式细胞术检测细胞周期分布和细胞凋亡.结果:3-溴丙酮酸在25~75 μg/mL范围内,对HepG-2细胞的增殖具有明显的抑制作用并呈现剂量依赖性.3-溴丙酮酸处理HepG-2细胞后,倒置显微镜观察到细胞生长稀疏,细胞质透亮度下降,细胞脱落增多;透射电镜观察到染色质固缩、边集,核质内可见空泡.流式细胞术结果显示3-溴丙酮酸可将HepG-2细胞阻滞于S期,且DNA直方图上可见亚二倍体峰.在3.125~25 μg/mL范围内,3-溴丙酮酸可剂量依赖性的诱导HepG-2细胞凋亡.结论:3-溴丙酮酸抑制HepG-2增殖并诱导HepG-2凋亡.

  11. Convergent Evolution of Fern-Specific Mitochondrial Group II Intron atp1i361g2 and Its Ancient Source Paralogue rps3i249g2 and Independent Losses of Intron and RNA Editing among Pteridaceae

    Science.gov (United States)

    Zumkeller, Simon Maria; Knoop, Volker; Knie, Nils

    2016-01-01

    Mitochondrial intron patterns are highly divergent between the major land plant clades. An intron in the atp1 gene, atp1i361g2, is an example for a group II intron specific to monilophytes (ferns). Here, we report that atp1i361g2 is lost independently at least 4 times in the fern family Pteridaceae. Such plant organelle intron losses have previously been found to be accompanied by loss of RNA editing sites in the flanking exon regions as a consequence of genomic recombination of mature cDNA. Instead, we now observe that RNA editing events in both directions of pyrimidine exchange (C-to-U and U-to-C) are retained in atp1 exons after loss of the intron in Pteris argyraea/biaurita and in Actiniopteris and Onychium. We find that atp1i361g2 has significant similarity with intron rps3i249g2 present in lycophytes and gymnosperms, which we now also find highly conserved in ferns. We conclude that atp1i361g2 may have originated from the more ancestral rps3i249g2 paralogue by a reverse splicing copy event early in the evolution of monilophytes. Secondary structure elements of the two introns, most characteristically their domains III, show strikingly convergent evolution in the monilophytes. Moreover, the intron paralogue rps3i249g2 reveals relaxed evolution in taxa where the atp1i361g2 paralogue is lost. Our findings may reflect convergent evolution of the two related mitochondrial introns exerted by co-evolution with an intron-binding protein simultaneously acting on the two paralogues. PMID:27492234

  12. Study of anticancer activity of quercetin and expression of PDGFR- βin HepG2 cells%Quercetin对HepG2细胞的抑制作用及PDGFR-β的表达

    Institute of Scientific and Technical Information of China (English)

    单智焱; 刘慧雯

    2005-01-01

    目的探讨植物化学物质槲皮素(Quercetin)对人类肝癌细胞HepG2的抑制作用和血小板衍生生长因子β受体(PDGFR-β)表达的关系.方法采用免疫组化SABC法观察Quercetin抑制HepG2中PDGFR-β表达,并采用透射电镜观察Quercetin作用后HepG2细胞的凋亡情况.结果细胞增殖率检测表明Quercetin可以抑制HepG2细胞的增殖,且呈剂量依赖性;Quercetin可以抑制HepG2细胞PDGFR-β的表达,且呈剂量依赖性;透射电镜下可见凋亡小体.结论槲皮素对HepG2细胞增殖有明显抑制作用,其机制可能是诱导PDGFR-β的增加,再通过PDGFR-β介导的细胞内信号体系控制细胞凋亡而实现的.

  13. Genetic Control of the Trigger for the G2/M Checkpoint

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Eric J. [Columbia University; Smilenov, Lubomir B. [Columbia University; Young, Erik F. [Columbia University

    2013-10-01

    system, the engagement of the G2/M checkpoint only occurs at doses where most of the cells are bound for mitotic catastrophe. Further, compound haploinsufficiency of various radiosensitizing genes does not impact the threshold of activation. The experiments confirm a threshold of activation for the G2/M checkpoint, hinting at two separate radiation response programs acting below and above this threshold. Small RNA transfer in bystander effect biology: Small regulatory RNA molecules have now risen in prominence and utility. Specific examples are small interfering RNAs (siRNA) which are employed in cell level expression ablation projects and micro-RNAs (miRNA) which are a pool of short transcription products which serve to modulate the expression of other transcripts emerging from the genome in a meta-regulatory fine tuning of gene expression. The existing tenets of bystander effect radiation biology involve the communication of inflammatory mediators or direct intercellular communication of reactive oxygen/nitrogen species in cell-to-cell communicative organelles called gap junctions. By ablating gap junctions, reducing the ROS/inflammatory cytokine expression one can attenuate bystander effect signaling in cell culture systems. We hypothesized that miRNAs are a competent intercellular communication molecule and therefore a possible component of the bystander response. This view is supported by the observation that miRNA are secreted from cells in exosomes found in the circulation. This circulating pool reports disease type and severity in humans. We proposed use of microbeam irradiation technology at our facilities and enhancement of this capability with a new sorting technology which would allow us to sort irradiated and non-irradiated cells with absolute fidelity. Pursuing direct quantitative transfer assessment, we succeeded in designing and constructing a new add-on sorting appliance which harmonized with our existing instruments. The sorter allowed us to gently sort

  14. Antisense oligonucleotide inhibition of hepatitis C virus genotype 4 replication in HepG2 cells

    Directory of Open Access Journals (Sweden)

    Omran Moataza H

    2006-06-01

    Full Text Available Abstract Background Hepatitis C (HCV viral infection is a serious medical problem in Egypt and it has a devastating impact on the Egyptian economy. It is estimated that over 15% of Egyptians are infected by the virus and thus finding a cure for this disease is of utmost importance. Current therapies for hepatitis C virus (HCV genotype 4 with interferon/ribavirin have not been successful and thus the development of alternative therapy for this genotype is disparately needed. Results Although previous studies utilizing viral subgenomic or full cDNA fragments linked to reporter genes transfected into adhered cells or in a cell free system showed promise, demonstration of efficient viral replication was lacking. Thus, we utilized HepG2 cells infected with native HCV RNA genomes in a replication competent system and used antisense phosphorothioate Oligonucleotides (S-ODN against stem loop IIId and the AUG translation start site of the viral polyprotein precursor to monitor viral replication. We were able to show complete arrest of intracellular replication of HCV-4 at 1 uM S-ODN, thus providing a proof of concept for the potential antiviral activity of S-ODN on native genomic replication of HCV genotype 4. Conclusion We have successfully demonstrated that by using two S-ODNs [(S-ODN1 (nt 326–348 and S-ODN-2 (nt 264–282], we were able to completely inhibit viral replication in culture, thus confirming earlier reports on subgenomic constructs and suggesting a potential therapeutic value in HCV type 4.

  15. Mangiferin, a Dietary Xanthone Protects Against Mercury-Induced Toxicity in HepG2 Cells

    Science.gov (United States)

    Agarwala, Sobhika; Rao, B. Nageshwar; Mudholkar, Kaivalya; Bhuwania, Ridhirama; Rao, B. S. Satish

    2012-01-01

    Mercury is one of the noxious heavy metal environmental toxicants and is a cause of concern for human exposure. Mangiferin (MGN), a glucosylxanthone found in Mangifera indica, reported to have a wide range of pharmacological properties. The objective of this study was to evaluate the cytoprotective potential of MGN, against mercury chloride (HgCl2) induced toxicity in HepG2 cell line. The cytoprotective effect of MGN on HgCl2 induced toxicity was assessed by colony formation assay, while antiapoptotic effect by fluorescence microscopy, flow cytometric DNA analysis, and DNA fragmentation pattern assays. Further, the cytoprotective effect of MGN against HgCl2 toxicity was assessed by using biochemical parameters like reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) by spectrophotometrically, mitochondrial membrane potential by flowcytometry and the changes in reactive oxygen species levels by DCFH-DA spectrofluoremetric analysis. A significant increase in the surviving fraction was observed with 50 µM of MGN administered two hours prior to various concentrations of HgCl2. Further, pretreatment of MGN significantly decreased the percentage of HgCl2 induced apoptotic cells. Similarly, the levels of ROS generated by the HgCl2 treatment were inhibited significantly (P < 0.01) by MGN. MGN also significantly (P < 0.01) inhibited the HgCl2 induced decrease in GSH, GST, SOD, and CAT levels at all the post incubation intervals. Our study demonstrated the cytoprotective potential of MGN, which may be attributed to quenching of the ROS generated in the cells due to oxidative stress induced by HgCl2, restoration of mitochondrial membrane potential and normalization of cellular antioxidant levels. PMID:20629087

  16. Gauged U(1) Lμ -Lτ model in light of muon g - 2 anomaly, neutrino mass and dark matter phenomenology

    Science.gov (United States)

    Patra, Sudhanwa; Rao, Soumya; Sahoo, Nirakar; Sahu, Narendra

    2017-04-01

    Gauged U(1) Lμ -Lτ model has been advocated for a long time in light of muon g - 2 anomaly, which is a more than 3σ discrepancy between the experimental measurement and the standard model prediction. We augment this model with three right-handed neutrinos (Ne ,Nμ ,Nτ) and a vector-like singlet fermion (χ) to explain simultaneously the non-zero neutrino masses and dark matter content of the Universe, while satisfying the anomalous muon g - 2 constraints. We find that the model suffers stringent constraints from the simultaneous explanation of neutrino trident production and muon g - 2 anomaly. In a large region of the parameter space, where contribution to muon g - 2 anomaly comes partially and yet not ruled out by neutrino trident production, the model can explain the positron excess, observed at PAMELA, Fermi-LAT and AMS-02 through dark matter annihilation, while satisfying the relic density and direct detection limits.

  17. Formation of carburized layer structure with reverted austenite on low-carbon martensitic steel 12Kh2G2NMFT

    Science.gov (United States)

    Ivanov, A. S.; Bogdanova, M. V.

    2013-03-01

    The structure of surface layer in low-carbon martensitic steel 12Kh2G2NMFT obtained by carburizing followed by high-temperature tempering and quenching from the intercritical temperature range is investigated.

  18. Nuclear matrix associated protein PML: an arsenic trioxide apoptosis therapeutic target protein in HepG2 cells

    Institute of Scientific and Technical Information of China (English)

    于鼎; 王子慧; 朱立元; 邱殷庆

    2003-01-01

    Objective To investigate arsenic trioxide (As2O3)-induced apoptosis and the effects on cell nuclear matrix related protein promyelocytic leukaemia (PML). Methods HepG2 cells were cultured in MEM medium and treated with 0.5, 2, 5 and 10 μmol/L As2O3 for either 24 h or 96 h at each concentration. In situ terminal deoxynucleotidyl transferase (TdT) labeling (TUNEL) and DNA ladders were used to detect apoptosis. Confocal microscopy and Western blotting were used to observe the expression of PML. Results The growth rates of HepG2 cells were slower in the As2O3 treated than the untreated control group. DNA ladder and TUNEL positive apoptotic cells could be detected in As2O3 treated groups. The expression of PML decreased in HepG2 cells with 2 μmol/L As2O3 treatment. Confocal images demonstrated that the expression of PML protein in HepG2 cell nuclei decreased after treatment with 2 μmol/L As2O3, and micropunctates characteristic of PML protein in HepG2 cell nuclei disappeared after treatment with 5 μmol/L As2O3.Conclusions Our results show that arsenic trioxide can significantly inhibit the growth of HepG2 cells in vitro. As2O3 induces apoptosis in HepG2 tumor cells in a time and concentration dependent manner. As2O3 may degrade the PML protein in HepG2 cell nuclei. The decreased expression of PML in As2O3 treated tumor cells is most likely to be caused by apoptosis. Nuclear matrix associated protein PML could be the target of As2O3 therapy.

  19. Cell cycle G2/M arrest through an S phase-dependent mechanism by HIV-1 viral protein R

    Directory of Open Access Journals (Sweden)

    Liang Dong

    2010-07-01

    Full Text Available Abstract Background Cell cycle G2 arrest induced by HIV-1 Vpr is thought to benefit viral proliferation by providing an optimized cellular environment for viral replication and by skipping host immune responses. Even though Vpr-induced G2 arrest has been studied extensively, how Vpr triggers G2 arrest remains elusive. Results To examine this initiation event, we measured the Vpr effect over a single cell cycle. We found that even though Vpr stops the cell cycle at the G2/M phase, but the initiation event actually occurs in the S phase of the cell cycle. Specifically, Vpr triggers activation of Chk1 through Ser345 phosphorylation in an S phase-dependent manner. The S phase-dependent requirement of Chk1-Ser345 phosphorylation by Vpr was confirmed by siRNA gene silencing and site-directed mutagenesis. Moreover, downregulation of DNA replication licensing factors Cdt1 by siRNA significantly reduced Vpr-induced Chk1-Ser345 phosphorylation and G2 arrest. Even though hydroxyurea (HU and ultraviolet light (UV also induce Chk1-Ser345 phosphorylation in S phase under the same conditions, neither HU nor UV-treated cells were able to pass through S phase, whereas vpr-expressing cells completed S phase and stopped at the G2/M boundary. Furthermore, unlike HU/UV, Vpr promotes Chk1- and proteasome-mediated protein degradations of Cdc25B/C for G2 induction; in contrast, Vpr had little or no effect on Cdc25A protein degradation normally mediated by HU/UV. Conclusions These data suggest that Vpr induces cell cycle G2 arrest through a unique molecular mechanism that regulates host cell cycle regulation in an S-phase dependent fashion.

  20. Early Transcriptional Responses of HepG2-A 16 Liver Cells to Infection by Plasmodium falciparum Sporozoites

    Science.gov (United States)

    2011-07-29

    286, ’JC 30, pp Early Transcriptional Responses of HepG2-A 16 Liver Cells to Infection by Plasmodium falciparum Sporozoites*[i] Received for...7500 and󈧏Sun BioMedical Technologies Inc., Ridgecrest, California 93555 Invasion of hepatocytes by Plasmodium sporozoites depos- ited by Anopheles...expression profiling of human HepG2-A16liver cells infected with Plasmodium falciparum sporozoites to understand the host early cellular events and

  1. 3D AMR simulations of the evolution of the diffuse gas cloud G2 in the Galactic Centre

    CERN Document Server

    Schartmann, M; Burkert, A; Gillessen, S; Genzel, R; Pfuhl, O; Eisenhauer, F; Plewa, P M; Ott, T; George, E M; Habibi, M

    2016-01-01

    With the help of 3D AMR hydrodynamical simulations we aim at understanding G2's nature, recent evolution and fate in the coming years. By exploring the possible parameter space of the diffuse cloud scenario, we find that a starting point within the disc of young stars is favoured by the observations, which may hint at G2 being the result of stellar wind interactions.

  2. Decorin protects human hepatoma HepG2 cells against oxygen-glucose deprivation via modulating autophagy.

    Science.gov (United States)

    Ju, Wenbo; Li, Shubo; Wang, Zhaohui; Liu, Yanfeng; Wang, Dawei

    2015-01-01

    This study is to investigate the effects of decorin (DCN) on human hepatoma HepG2 cells under oxygen-glucose deprivation (OGD) condition. HepG2 cells were cultured under OGD condition. CCK-8 assay was used to assess the cell survival, and flow cytometry was performed to detect the apoptosis. Protein expression levels were detected with Western blot analysis. Transfection was performed with liposome, and cells were screened with G418. The cell survival rates were significantly decreased in the OGD groups. When treated with autophagy inhibitor 3-MA, the survival rates were further declined in these cells. Moreover, flow cytometry indicated that apoptosis occurred in the HepG2 cells under OGD condition, and the apoptosis rates were significantly increased by the 3-MA treatment. Western blot analysis showed that, the expression levels of DCN were significantly elevated in OGD-preconditioned HepG2 cells. Meanwhile, the expression level of Beclin1 and the LC3BI/LC3BII ratio were significantly increased, while the expression level of P62 was significantly decreased, in HepG2 cells under OGD condition. Over-expression of DCN significantly increased the expression level of Beclin1 and the LC3BI/LC3BII ratio, while no significant changes were observed in the P62 expression level, in HepG2 cells. Under the OGD condition, the apoptosis rate was also significantly decreased in DCN-transfected HepG2 cells. DCN protects HepG2 cells against OGD-induced injury, via regulating autophagy. These results might contribute to a better understanding of the roles of DCN and autophagy in hepatocellular carcinoma, and the potential treatment for the disease.

  3. Autophagy inhibition sensitizes KU-0063794-mediated anti-HepG2 hepatocellular carcinoma cell activity in vitro and in vivo.

    Science.gov (United States)

    Yongxi, Tong; Haijun, Huang; Jiaping, Zheng; Guoliang, Shao; Hongying, Pan

    2015-09-25

    Recent studies have indicated that mammalian target of rapamycin (mTOR) signaling has a critical role in the pathogenesis of hepatocellular carcinoma (HCC). In the current study, we investigated the activity of KU-0063794, a novel mTOR kinase inhibitor, against HepG2 HCC cells. Our results demonstrated that KU-0063794 blocked mTOR complex 1/2 (mTORC1/2) activation, and downregulated mTOR-regulated genes (Cyclin D1 and hypoxia-inducible factor 1α) in HepG2 cells. Consequently, KU-0063794 induced significant anti-survival and pro-apoptotic activities against HepG2 cells. When analyzing the possible KU-0063794-resistance factors, we showed that KU-0063794 induced cyto-protective autophagy activation in HepG2 cells, evidenced by GFP-light chain 3B (LC3B) puncta formation, p62 degradation, Beclin-1 expression and LC3B-I to LC3B-II conversion. Correspondingly, autophagy inhibitors, including bafliomycin A1, 3-methyladenine (3-MA) and chloroquine, dramatically enhanced KU-0063794-induced cytotoxicity against HepG2 cells. Further, RNAi knockdown of Beclin-1 also increased KU-0063794 sensitivity in HepG2 cells. In vivo, oral administration of KU-0063794 repressed HepG2 xenograft growth in severe combined immunodeficient (SCID) mice, and its activity was further enhanced with co-administration of the autophagy inhibitor 3-MA. In summary, KU-0063794 inhibits HepG2 cell growth in vitro and in vivo, its activity could be further enhanced with autophagy inhibition. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Cytotoxicity, oxidative stress, and apoptosis in HepG2 cells induced by ionic liquid 1-methyl-3-octylimidazolium bromide.

    Science.gov (United States)

    Li, Xiaoyu; Ma, Junguo; Wang, Jianji

    2015-10-01

    The present study aimed to determine the cytotoxicity of 1-methyl-3-octylimidazolium bromide ([C8mim]Br) on the human hepatocellular carcinoma (HepG2) cells in order to elucidate the biochemical and molecular mechanism of [C8mim]Br-cytotoxicity. For this purpose, cell viability, oxidative stress, apoptosis, caspase activity, and apoptosis-related gene expression in HepG2 cells following [C8mim]Br-exposure were evaluated. The results showed that viability of HepG2 cells was decreased by [C8mim]Br-exposure in a concentration-dependent pattern. Moreover, biochemical assays reveal that [C8mim]Br-exposure can induce apoptosis, cause overproduction of reactive oxygen species (ROS), inhibit superoxide dismutase and catalase, reduce glutathione content, and increase the cellular malondialdehyde level of HepG2 cells. The transcriptions of p53 and bax were markedly up-regulated while bcl-2 was significantly down-regulated in HepG2 cells after [C8mim]Br-exposure, suggesting that p53 and bcl-2 family may be involved in the cytotoxicity and apoptosis of HepG2 cells caused by [C8mim]Br. In addition, we also found that caspase-3, caspase-8, and caspase-9 were significantly activated in HepG2 cells following [C8mim]Br-exposure. Our results suggest that ROS may be a key early signal of [C8mim]Br-induced apoptosis and caspases play a key role in the initiation and execution of apoptosis of HepG2 cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Quercetin reduces cyclin D1 activity and induces G1 phase arrest in HepG2 cells.

    Science.gov (United States)

    Zhou, Jin; Li, L U; Fang, L I; Xie, Hua; Yao, Wenxiu; Zhou, Xiang; Xiong, Zhujuan; Wang, L I; Li, Zhixi; Luo, Feng

    2016-07-01

    Quercetin is able to inhibit proliferation of malignant tumor cells; however, the exact mechanism involved in this biological process remains unclear. The current study utilized a quantitative proteomic analysis to explore the antitumor mechanisms of quercetin. The leucine of HepG2 cells treated with quercetin was labeled as d3 by stable isotope labeling by amino acids in cell culture (SILAC). The isotope peaks of control HepG2 cells were compared with the d3-labeled HepG2 cells by mass spectrometry (MS) to identify significantly altered proteins. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analyses were subsequently employed to verify the results of the MS analysis. A flow cytometry assay was designed to observe the influence of various quercetin treatment concentrations on the cell cycle distribution of HepG2 cells. The results indicated that quercetin is able to substantially inhibit proliferation of HepG2 cells and induce an obvious morphological alteration of cells. According to the MS results, the 70 credibly-changed proteins that were identified may play important roles in multiple cellular processes, including protein synthesis, signaling, cytoskeletal processes and metabolism. Among these functional proteins, the expression of cyclin D1 (CCND1) was found to be significantly decreased. RT-PCR and western blot analyses verified the SILAC-MS results of decreased CCND1 expression. In summary, flow cytometry revealed that quercetin is able to induce G1 phase arrest in HepG2 cells. Based on the aforementioned observations, it is suggested that quercetin exerts antitumor activity in HepG2 cells through multiple pathways, including interfering with CCND1 gene expression to disrupt the cell cycle and proliferation of HepG2 cells. In the future, we aim to explore this effect in vivo.

  6. Effects of Cinnamon Polyphenols Improving HepG2 Cells Insulin Resistance%肉桂多酚改善HepG2细胞胰岛素抵抗作用研究

    Institute of Scientific and Technical Information of China (English)

    卢兆莲; 黄才国

    2013-01-01

    目的:探讨肉桂多酚对HepG2细胞胰岛素抵抗的影响.方法:将HepG2细胞分为空白组、模型组、二甲双胍组(剂量10μg/mL)和肉桂多酚组(剂量分别为5、10和15 μ g/mL),用四甲基偶氮唑盐(MTT)的方法检测肉桂多酚对细胞活性的影响;采用高胰岛素诱导的方法建立胰岛素抵抗的细胞模型,研究肉桂多酚对胰岛素抵抗的HepG2细胞葡萄糖消耗的影响.结果:肉桂多酚浓度大于15μg/mL时,对HepG2细胞的生长活性具有抑制作用;肉桂多酚可促进HepG2细胞和胰岛素抵抗的HepG2细胞对葡萄糖的消耗,且呈明显的剂量依赖性.结论:肉桂多酚能明显促进HepG2细胞和胰岛素抵抗的HepG2细胞对葡萄糖的消耗,提高了细胞对胰岛素的敏感性,对高浓度的胰岛素诱导的胰岛素抵抗具有明显的改善作用.%Objective: To study the influence of the cinnamon polyphenols on HepG2 cells insulin resistance. Methods:HepG2 cells were divided into control group, model group, metformin group (10 μg/mL)and cinnamon polyphenols groups with different doses (5,10,15μg/mL ). The effect of cinnamon polyphenols on viability of HepG2 cells was determined by 3- ( 4,5-dimethylthiazol-2-yl ) -2, 5-diphenylterazolium bromide ( MTT ) assay; insulin resistance cell model was induced by high concentrations of insulin, the hypoglycemic effect of cinnamon polyphenols in HepG2 cells was detected. Results : At the concentrations ( 1~ 15 μg/mL), the cinnamon polyphenols had no depressant effect on the cells activity. Cinnamon polyphenols could significantly promote extracellular glucose consumption in the HepG2 cells and the insulin resistance, moreover, with the increase of concentration, cinnamon polyphenols had more apparent hypoglycemic effect. Conclusion : Cinnamon polyphenols could significantly promote extracellular glucose consumption and the insulin resistance in the normal HepG2 cells, the low concentration can significantly enhance the cell

  7. 胡椒碱对人肝癌HepG2细胞抗肿瘤活性的体外实验研究%Inhibitory effect of piperine on human HepG2 hepatocarcinoma cell in vitro

    Institute of Scientific and Technical Information of China (English)

    郑斌; 王欣; 麻彤辉

    2012-01-01

    Objective To study the inhibitory effect of pipcrinc on HcpG2 cell in vitro. Methods The human hepa-tocarcinoma HcpG2 cells were cultured in vitro and divided into control group and pipcrinc-trcatcd group. MTT assay was performed to evaluate the proliferation inhibitory effects of pipcrinc on HcpG2 cells and freshly prepared peripheral white blood cells. Hocchst 33258 nuclear staining was performed to detect the mode of cell death. Flow cytomctry was used to assess the effects of pipcrinc treatment on cell apoptosis in human HcpG2 cells. Results The inhibitory effect of pipcrinc treatment on HcpG2 cell proliferation increases with the dose, and the half inhibition concentration(IC50) was 15. 13 + 3. 21 μmol/L, which was lower than that for peripheral white blood cell(IC50 = 64. 52 + 5. 32 μmol/L). Pipcrinc treated HcpG2 cells showed typical apoptotic characteristics. After treated with 20 μmol/L pipcrinc for 24 h,the apoptosis rate increased from 2. 89% of control group to 21. 76%. Conclusion Pipcrinc has cytotoxicity effect on cultured human HcpG2 cells in vitro,and can inhibit proliferation and induce apoptosis.%目的 探讨胡椒碱(piperine)对人HpeG2肝癌细胞株的增殖、杀伤和细胞凋亡的影响,为肝癌的治疗提供理论依据.方法 体外培养的HpeG2细胞,采用MTT比色法检测不同浓度胡椒碱对体外培养的HepG2细胞和新分离的外周血白细胞的增殖抑制作用.Hoechst 33258染色观察细胞凋亡形态,采用流式细胞术测定胡椒碱对HepG2细胞的凋亡.结果 胡椒碱对HepG2细胞增殖的抑制率随着浓度的升高而增加,半量抑制浓度(IC50)为15.13±3.21 μmol/L,低于其对外周血白细胞的抑制率(64.52±5.32 μmol/L).Hoechst 33258染色后,胡椒碱处理癌细胞组表现出典型的细胞凋亡特征,流式细胞仪检测20 μmol/L的胡椒碱处理HepG2细胞24 h后,细胞凋亡率由对照组的2.89%上升到了21.76%.结论 胡椒碱具有抑制HepG2细胞增殖和诱导凋

  8. HIV-1 Vpr protein activates the NF-κB pathway to promote G2/M cell cycle arrest

    Institute of Scientific and Technical Information of China (English)

    Zhibin Liang; Ruikang Liu; Yongquan Lin; Chen Liang; Juan Tan; Wentao Qiao

    2015-01-01

    Viral protein R(Vpr) plays an important role in the replication and pathogenesis of Human immunodeficiency virus type 1(HIV-1). Some of the various functions attributed to Vpr, including the induction of G2/M cell cycle arrest, activating the NF-κB pathway, and promoting viral reverse transcription, might be interrelated. To test this hypothesis, a panel of Vpr mutants were investigated for their ability to induce G2/M arrest and to activate the NF-κB pathway. The results showed that the Vpr mutants that failed to activate NF-κB also lost the activity to induce G2/M arrest, which suggests that inducing G2/M arrest via Vpr depends at least partially on the activation of NF-κB. This latter possibility is supported by data showing that knocking down the key factors in the NF-κB pathway – p65, Rel B, IKKα, or IKKβ– partially rescued the G2/M arrest induced by Vpr.Our results suggest that the NF-κB pathway is probably involved in Vpr-induced G2/M cell cycle arrest.

  9. Investigation of quercetin-induced HepG2 cell apoptosis-associated cellular biophysical alterations by atomic force microscopy.

    Science.gov (United States)

    Pi, Jiang; Li, Baole; Tu, Lvying; Zhu, Haiyan; Jin, Hua; Yang, Fen; Bai, Haihua; Cai, Huaihong; Cai, Jiye

    2016-01-01

    Quercetin, a wildly distributed bioflavonoid, has been proved to possess excellent antitumor activity on hepatocellular carcinoma (HCC). In the present study, the biophysical properties of HepG2 cells were qualitatively and quantitatively determined using high resolution atomic force microscopy (AFM) to understand the anticancer effects of quercetin on HCC cells at nanoscale. The results showed that quercetin could induce severe apoptosis in HepG2 cells through arrest of cell cycle and disruption of mitochondria membrane potential. Additionally, the nuclei and F-actin structures of HepG2 cells were destroyed by quercetin treatment as well. AFM morphological data showed some typical apoptotic characterization of HepG2 cells with increased particle size and roughness in the ultrastructure of cell surface upon quercetin treatment. As an important biophysical property of cells, the membrane stiffness of HepG2 cells was further quantified by AFM force measurements, which indicated that HepG2 cells became much stiffer after quercetin treatment. These results collectively suggest that quercetin can be served as a potential therapeutic agent for HCC, which not only extends our understanding of the anticancer effects of quercetin against HCC cells into nanoscale, but also highlights the applications of AFM for the investigation of anticancer drugs.

  10. Cytotoxicity of mequindox and its metabolites in HepG2 cells in vitro and murine hepatocytes in vivo.

    Science.gov (United States)

    Liu, Yingchun; Jiang, Wei; Chen, Yongjun; Liu, Yanyan; Zeng, Peng; Xue, Feiqun; Wang, Quan

    2016-02-01

    Mequindox, a quinoxaline 1,4-dioxide, is widely used as a feed additive in the Chinese livestock industry because of its effective antibacterial properties. Many recent studies have found that mequindox is rapidly metabolized to numerous metabolites following administration to animals. There have, however, been few reports describing the cytotoxicity of mequindox metabolites. In this study, HepG2 cells were treated with mequindox (0, 2, 10, 50 or 100 μg/ml) or its major metabolites (0, 40, 100, 250 or 500 μg/ml) for 24h. Mice were administrated with mequindox (0, 50, 200 or 500 mg/kg.bw) for five days. DNA damage in the HepG2 cells and mouse hepatocytes was then assessed using an SCGE assay. The cell cycle of the HepG2 cells was also determined by flow cytometry. Mequindox was found to induce cell cycle arrest to the G2/M phase and cause dose-dependent DNA damage in HepG2 cells in vitro and in murine hepatocytes in vivo. Compared with mequindox, the major metabolites had much smaller effects on the cell cycle and caused much less DNA damage in HepG2 cells. And the results indicated that the process of metabolites formed by reduction of the MEQ acetyl group or reduction of the N → O groups could contribute to DNA damage in murine hepatocytes in vivo. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Effect of taurine on the proliferation and apoptosis of human hepatocellular carcinoma HepG2 cells.

    Science.gov (United States)

    Tu, Shuo; Zhang, Xiali; Luo, Daya; Liu, Zhuoqi; Yang, Xiaohong; Wan, Huifang; Yu, Lehan; Li, Hua; Wan, Fusheng

    2015-07-01

    The aim of the present study was to observe the effect and molecular mechanism of taurine (Tau) on the cell proliferation and apoptosis of human hepatocellular carcinoma (HHCC) HepG2 cells. HHCC HepG2 cells were used as target cells, and the cell survival rate was assessed using a multi-time-step method. The p53 upregulated modulator of apoptosis (PUMA) gene was transiently transfected by lipofection and subsequently silenced with specific small interfering (si)RNA. The cell apoptosis rate was detected by flow cytometry, and protein expression levels were analyzed with western blotting. Addition of 20-160 mM Tau was shown to have a significant inhibitory effect on cell proliferation, while promoting the induction of HHCC HepG2 cell apoptosis (PHepG2 cells. In addition, transfection of the PUMA gene increased the protein expression of B-cell lymphoma-2-associated X and reduced the expression of B-cell lymphoma-2 (PHepG2 cells (PHepG2 cells.

  12. Autophagy in anti-apoptotic effect of augmenter of liver regeneration in HepG2 cells.

    Science.gov (United States)

    Shi, Hong-Bo; Sun, Hai-Qing; Shi, Hong-Lin; Ren, Feng; Chen, Yu; Chen, De-Xi; Lou, Jin-Li; Duan, Zhong-Ping

    2015-05-07

    To investigate the role of autophagy in the anti-apoptotic effect of augmenter of liver regeneration (ALR). Autophagy was induced through serum deprivation. An ALR-expressing plasmid was transfected into HepG2 cells, and autophagic flux was determined using fluorescence microscopy, electron microscopy, Western blot and quantitative polymerase chain reaction (qPCR) assays. After ALR-expressing plasmid transfection, an autophagy inhibitor [3-methyladenine (3-MA)] was added to HepG2 cells, and apoptosis was observed using fluorescence microscopy and flow cytometry. Autophagy was activated in HepG2 cells, peaking at 24 h after serum deprivation. Microtubule-associated protein light chain three-II levels were higher in HepG2 cells treated with ALR than in control cells, fluorescence microscopy, electron microscopy and qPCR studies showed the similar trend, and p62 levels showed the opposite trend, which indicated that ALR may play an important role in increasing autophagy flux. The numbers of apoptotic cells were substantially higher in HepG2 cells treated with both ALR and 3-MA than in cells treated with ALR alone. Therefore, the protective effect of ALR was significantly attenuated or abolished when autophagy was inhibited, indicating that the anti-apoptotic effect of ALR may be related to autophagy. ALR protects cells from apoptosis partly through increased autophagy in HepG2 cells and may be valuable as a new therapeutic treatment for liver disease.

  13. Cisplatin combined with hyperthermia kills HepG2 cells in intraoperative blood salvage but preserves the function of erythrocytes.

    Science.gov (United States)

    Yang, Jin-ting; Tang, Li-hui; Liu, Yun-qing; Wang, Yin; Wang, Lie-ju; Zhang, Feng-jiang; Yan, Min

    2015-05-01

    The safe use of intraoperative blood salvage (IBS) in cancer surgery remains controversial. Here, we investigated the killing effect of cisplatin combined with hyperthermia on human hepatocarcinoma (HepG2) cells and erythrocytes from IBS in vitro. HepG2 cells were mixed with concentrated erythrocytes and pretreated with cisplatin (50, 100, and 200 μg/ml) alone at 37 °C for 60 min and cisplatin (25, 50, 100, and 200 μg/ml) combined with hyperthermia at 42 °C for 60 min. After pretreatment, the cell viability, colony formation and DNA metabolism in HepG2 and the Na(+)-K(+)-ATPase activity, 2,3-diphosphoglycerate (2,3-DPG) concentration, free hemoglobin (Hb) level, osmotic fragility, membrane phosphatidylserine externalization, and blood gas variables in erythrocytes were determined. Pretreatment with cisplatin (50, 100, and 200 μg/ml) combined with hyperthermia (42 °C) for 60 min significantly decreased HepG2 cell viability, and completely inhibited colony formation and DNA metabolism when the HepG2 cell concentration was 5×10(4) ml(-1) in the erythrocyte (P0.05). In conclusion, pretreatment with cisplatin (50 μg/ml) combined with hyperthermia (42 °C) for 60 min effectively eliminated HepG2 cells from IBS but did not significantly affect erythrocytes in vitro.

  14. Galactomannan from Schizolobium amazonicum seed and its sulfated derivatives impair metabolism in HepG2 cells.

    Science.gov (United States)

    Cunha de Padua, Monique Meyenberg; Suter Correia Cadena, Silvia Maria; de Oliveira Petkowicz, Carmen Lucia; Martinez, Glaucia Regina; Rodrigues Noleto, Guilhermina

    2017-08-01

    This study evaluated the effects of native galactomannan from Schizolobium amazonicum seeds and its sulfated forms on certain metabolic parameters of HepG2 cells. Aqueous extraction from S. amazonicum seeds furnished galactomannan with 3.2:1 Man:Gal ratio (SAGM) and molar mass of 4.34×10(5)g/mol. The SAGM fraction was subjected to sulfation using chlorosulfonic acid to obtain SAGMS1 and SAGMS2 with DS of 0.4 and 0.6, respectively. Cytotoxicity of SAGM, SAGMS1, and SAGMS2 was evaluated in human hepatocellular carcinoma cells (HepG2). After 72h, SAGM decreased the viability of HepG2 cells by 50% at 250μg/mL, while SAGMS1 reduced it by 30% at the same concentration. SAGM, SAGMS1, and SAGMS2 promoted a reduction in oxygen consumption and an increase in lactate production in non-permeabilized HepG2 cells after 72h of treatment. These results suggest that SAGM, SAGMS1, and SAGMS2 could be recognized by HepG2 cells and might trigger alterations that impair its survival. These effects could be implicated in the modification of the oxidative phosphorylation process in HepG2 cells and activation of the glycolytic pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Cytotoxic effect of oxaloacetate on HepG2-human hepatic carcinoma cells via apoptosis and ROS accumulation.

    Science.gov (United States)

    Jiao, Y; Ji, L; Kuang, Y; Yang, Q

    2017-01-01

    Oxaloacetate (OA) is one of the intermediates of the Krebs cycle. In addition to its role in energy production, OA may have other effects on the cell. We report here that OA could have a cell type dependent cytotoxic effect on the human hepatic carcinoma cell line HepG2 through induction of apoptosis and reactive oxygen species (ROS) accumulation. In our study, OA decreased the viability and colony formation of HepG2 cells and induced cell death. Caspase-3 activity was increased, the pro-apoptotic protein Bax was up-regulated, and the anti-apoptotic protein Bcl-2 was down-regulated in OA-treated HepG2 cells indicating that apoptosis through the intrinsic pathway was involved in the cell death. The ROS level in OA-treated HepG2 cells was increased. The anti-oxidant N-acetylcysteine (NAC) and glutathione (GSH) prevented the OA-induced decrease in cell but did not alter the enhanced apoptotic Bax/Bcl-2 mRNA ratio. These results suggest that the OA-induced apoptosis of HepG2 cell is not driven by oxidative damage and at least two distinct mechanisms, one mediated by ROS and one involving apoptosis, result in the cytotoxic effects of OA on HepG2 cells. These studies expand the biological functional repertoire of OA and provide a mechanism by which hepatocellular carcinoma may be targeted by OA.

  16. Synthesis and Evaluation of New Pyrazoline Derivatives as Potential Anticancer Agents in HepG-2 Cell Line

    Directory of Open Access Journals (Sweden)

    Weijie Xu

    2017-03-01

    Full Text Available Cancer is a major public health concern worldwide. Adverse effects of cancer treatments still compromise patients’ quality of life. To identify new potential anticancer agents, a series of novel pyrazoline derivatives were synthesized and evaluated for cytotoxic effects on HepG-2 (human liver hepatocellular carcinoma cell line and primary hepatocytes. Compound structures were confirmed by 1H-NMR, mass spectrometry, and infrared imaging. An in vitro assay demonstrated that several compounds exerted cytotoxicity in the micromolar range. Benzo[b]thiophen-2-yl-[5-(4-hydroxy-3,5-dimethoxy-phenyl-3-(2-hydroxy-phenyl-4,5-dihydo-pyrazol-1-yl]-methanone (b17 was the most effective anticancer agent against HepG-2 cells owing to its notable inhibitory effect on HepG-2 with an IC50 value of 3.57 µM when compared with cisplatin (IC50 = 8.45 µM and low cytotoxicity against primary hepatocytes. Cell cycle analysis and apoptosis/necrosis evaluation using this compound revealed that b17 notably arrested HepG-2 cells in the G2/M phase and induced HepG-2 cells apoptosis. Our findings indicate that compound b17 may be a promising anticancer drug candidate.

  17. Effect of solanine on N-acetylaransferase activity in HepG2 cell%龙葵碱对HepG2细胞NAT1酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    高世勇; 苏怡君; 季宇彬

    2010-01-01

    探讨龙葵碱对HepG2人肝癌细胞的N-乙酰基转移酶1(NAT1)酶活性的影响. 采用高效液相色谱法(HPLC),以对氨基苯甲酸(PABA)为底物,以PABA被NAT1乙酰化为乙酰对氨基苯甲酸(Ac-PABA)的量反应NAT1酶的活性.观察不同质量浓度、不同时间龙葵碱对完整HepG2细胞NAT1酶活性的影响;龙葵碱对HepG2细胞细胞质中NAT1酶活性的影响.结果表明,在NAT1酶活性测定中,龙葵碱能显著降低HepG2完整细胞NAT1的活性;龙葵碱能够降低HepG2细胞质内NAT1的活性,且作用具有剂量依赖性;随着时间的增加NAT1转化产物的量逐渐增加,但龙葵碱能显著降低同一时段NAT1的活性.提示龙葵碱通过抑制HepG2细胞中NAT1的活性是龙葵碱抑制人肝癌细胞HepG2增殖的作用机制之一.

  18. In HepG2 cells, coexisting carnitine deficiency masks important indicators of marginal biotin deficiency.

    Science.gov (United States)

    Bogusiewicz, Anna; Boysen, Gunnar; Mock, Donald M

    2015-01-01

    A large number of birth defects are related to nutrient deficiencies; concern that biotin deficiency is teratogenic in humans is reasonable. Surprisingly, studies indicate that increased urinary 3-hydroxyisovalerylcarnitine (3HIAc), a previously validated marker of biotin deficiency, is not a valid biomarker in pregnancy. In this study we hypothesized that coexisting carnitine deficiency can prevent the increase in 3HIAc due to biotin deficiency. We used a 2-factor nutrient depletion design to induce isolated and combined biotin and carnitine deficiency in HepG2 cells and then repleted cells with carnitine. To elucidate the metabolic pathogenesis, we quantitated intracellular and extracellular free carnitine, acylcarnitines, and acylcarnitine ratios using liquid chromatography-tandem mass spectrometry. Relative to biotin-sufficient, carnitine-sufficient cells, intracellular acetylcarnitine increased by 90%, propionylcarnitine more than doubled, and 3HIAc increased by >10-fold in biotin-deficient, carnitine-sufficient (BDCS) cells, consistent with a defensive mechanism in which biotin-deficient cells transesterify the acyl-coenzyme A (acyl-CoA) substrates of the biotin-dependent carboxylases to the related acylcarnitines. Likewise, in BDCS cells, the ratio of acetylcarnitine to malonylcarnitine and the ratio of propionylcarnitine to methylmalonylcarnitine both more than tripled, and the ratio of 3HIAc to 3-methylglutarylcarnitine (MGc) increased by >10-fold. In biotin-deficient, carnitine-deficient (BDCD) cells, the 3 substrate-derived acylcarnitines changed little, but the substrate:product ratios were masked to a lesser extent. Moreover, carnitine repletion unmasked biotin deficiency in BDCD cells as shown by increases in acetylcarnitine, propionylcarnitine, and 3HIAc (each increased by >50-fold). Likewise, ratios of acetylcarnitine:malonylcarnitine, propionylcarnitine:methylmalonylcarnitine, and 3HIAc:MGc all increased by >8-fold. Our findings provide strong

  19. Alisol A 24-Acetate Prevents Hepatic Steatosis and Metabolic Disorders in HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Lu Zeng

    2016-11-01

    Full Text Available Background: Non-alcoholic fatty liver disease (NAFLD is closely associated with metabolic disorders including hepatic lipid accumulation and inflammation. Alisol A 24-acetate, a triterpene from Alismatis rhizome, has multiple biologic activities such as hypolipidemic, anti-inflammatory and anti-diabetic. Thus we hypothesized that Alisol A 24 -acetate would have effect on NAFLD. The present study was conducted to investigate the therapeutic effects and potential mechanisms of Alisol A 24-acetate against hepatic steatosis in a free fatty acids (FFAs induced NAFLD cell model. Methods: This study was divided into four groups including Control group, Model group (FFA group, Alisol A 24-acetate (FFA+A group, Fenofibrate (FFA+F group. Preventive role of Alisol A 24-acetate was evaluated using 10µM Alisol A 24-acetate plus 1 mM FFA (oleate:palmitate=2:1 incubated with HepG2 cells for 24 h, which was determined by Oil Red O Staining, Oil Red O based colorimetric assay and intracellular triglyceride (TG content. Besides, the inflammatory cytokines tumor necrosis factor (TNF- α, interleukin (IL-6 levels as well as the protein and mRNA expressions that were involved in fatty acid synthesis and oxidation including Adiponectin, AMP-activated protein kinase (AMPK α, peroxisome proliferator-activated receptor (PPAR α, sterol regulatory element binding protein 1c (SREBP-1c, acetyl-CoA carboxylase (ACC, fatty acid synthase (FAS, carnitine palmitoyltransferase 1 (CPT1 and acyl coenzyme A oxidase 1 (ACOX1 were detected. Results: Alisol A 24-acetate significantly decreased the numbers of lipid droplets, Oil Red O lipid content, and intracellular TG content. Besides, inflammatory cytokines TNF-α, IL-6 levels were markedly inhibited by Alisol A 24-acetate. Furthermore, Alisol A 24-acetate effectively increased the protein and mRNA expressions of Adiponectin, the phosphorylation of AMPKα, CPT1 and ACOX1, whereas decreased SREBP-1c, the phosphorylation of ACC and

  20. The mechanisms of apoptosis induced by TanshinoneⅡA in human hepatoma HepG2 cells%丹参酮ⅡA诱导人肝癌HepG2细胞凋亡的机制

    Institute of Scientific and Technical Information of China (English)

    陈阳; 赵秋宇; 宋囡; 贾连群

    2015-01-01

    Objective To examine the effects of tanshinoneⅡA on growth and apoptosis in HepG2 cells.Methods HepG2 cells were treated with various concentrations of tanshinoneⅡA.Assays were performed to determine cell viability;cell cycle arrest, apoptosis and protein expression were measured by MTT, MUSE cytoanalyze, PI staining and Western blotting.Results After HepG2 cells were treated with different concentrations of tanshinoneⅡA ( 5~50 μmol/L) , the growth of HepG2 cells were significantly inhibited compared with those of control group(P<0.01), the HepG2 cells displayed typical morphological changes and induced G2/M-phase arrest of the cell cycle and apoptosis.TanshinoneⅡA increased expressions of p53 and Bax as well as caused down-regulation of Bcl-2 expression.Conclusions TanshinoneⅡA could inhibit the growth of HepG2 cells via inducing G2/M arrest followed by the mitochondrial pathway of apoptosis.%目的:探讨中药活性单体丹参酮ⅡA 对人肝癌 HepG2细胞株增殖抑制和诱导凋亡的可能机制。方法用5、10、20、30、40、50μmol/L丹参酮ⅡA处理HepG2细胞,应用MTT法分析细胞活力,MUSE细胞分析仪、PI染色等检测细胞增殖抑制、细胞周期以及凋亡情况。免疫蛋白印迹技术检测p53、Bax及Bcl-2等凋亡相关蛋白的表达。结果5~50μmol/L丹参酮ⅡA显著降低细胞存活率( P<0.01),形态学观察可见细胞凋亡改变,细胞发生G2/M期周期阻滞。免疫印迹结果显示丹参酮ⅡA上调 p53、Bax蛋白的表达,下调 Bcl-2蛋白的表达。结论丹参酮ⅡA对HepG2细胞的增殖抑制作用可能部分通过诱导细胞G2/M周期阻滞和线粒体途径凋亡实现。

  1. EFFECT OF INOSITOL HEXAPHOSPHATE ON MULTIPLICATION OF LIVER CANCER CELL HepG2%肌醇六磷酸对肝癌HepG2细胞增殖的影响

    Institute of Scientific and Technical Information of China (English)

    杨伟品; 宋扬; 孟显锋

    2011-01-01

    Objective To study the effect and mechanisms of inositol hexaphosphate (IP6) on proliferation of human liver cancer cell HepG2. Methods HepG2 cells were cultured in vitro and treated with various concentrations of IP6. MTT assay was used to observe the effect of IP6 on proliferation of HepG2 cells, and plate colony-forming assay to detect the colony-forming efficiency. The expressions of P53 and P21 were tested by immunocytochemical technique. Results Compared with the control, IP6 group (1.0, 2.0, 3.0 mmol/L) declined the colony formation of the cells and raised the clone-inhibiting rate. IP6 inhibited the expression of P53, and promoted the expression of P21. Conclusion IP6 plays a role in inhibiting the proliferation and declining the clonality of HepG2 cells. The mechanism of inhibiting the proliferation of HepG2 cells is, probably, by regulating the expressions of P53 and P21, resulting in blockage of the cell cycle.%目的 研究肌醇六磷酸(IP6)对人肝癌HepG2细胞增殖的影响并探讨其作用机制.方法 体外培养HepG2细胞,应用MTT实验观察IP6对HepG2细胞增殖的影响,平板集落形成实验检测IP6作用后HepG2细胞的克隆形成能力,免疫细胞化学法检测IP6作用后HepG2细胞突变型P53、细胞周期抑制蛋白P21的表达.结果 IP6能抑制HepG2细胞的增殖,且呈剂量-时间效应关系;与对照组比,IP6作用组(1.0、2.0、3.0 mmol/L)可降低细胞集落形成能力,使克隆形成抑制率升高;IP6可抑制P53的表达,促进P21的表达.结论 IP6具有抑制HepG2细胞增殖、降低其克隆形成能力的作用,可能通过调节P53、P21的表达,使细胞周期发生阻滞,从而抑制HepG2细胞的增殖.

  2. 奥美拉唑对肝癌HepG2细胞增殖与凋亡的影响%Effects of Omeprazole on the Proliferation and Apoptosis of Hepatoma Cell Line HepG2

    Institute of Scientific and Technical Information of China (English)

    魏艳; 梁宁林; 朱永军; 吴文超; 刘小菁; 杨丽

    2012-01-01

    Objective To investigate the effects of omeprazole (OME), a proton pump inhibitor, on the proliferation and apoptosis of human hepatoma cell line HepG2. Methods HepG2 cells were cultured to the logarithmic phase, and then treated with OME of different concentrations (10, 20, 40, 80, 160 mg/L) for 24 h or 48 h. Cell proliferation was evaluated by MTT assay, DNA synthesis was measured with 5 ethynyl-2'-deoxyuridine (Edu) fluorescent assay and the apoptosis of cells was measured by the Hoechst33342 assay. Results MTT assay showed that OME (40, 80 and 160 mg/L concentrations) could inhibit the proliferation of HepG2 cells for 24 h or 48 h treatment (P<0. 05) and 80 mg/L group has strongest effect. Compared with that of 24 h treatment, the same concentration of OME could inhibit HepG2 more significantly with 48 h treatment. After different concentrations of OME treatment for 24 h and then incubation with Edu for 2 h, compared with the control group, the proportion of Cells in S phase in 20, 40, 80, 160 mg/L groups decreased. Hoechst33342 staining demonstrated that treatment with OME (40,80,160 mg/L) for 24 h could significantly promote the cell apoptosis. Conclusion Omeprazole could inhibit human hepatoma cell line HepG2 cell proliferation and promote apoptosis.%目的 探讨质子泵抑制剂奥美拉唑(omeprazole,OME)对肝癌HepG2细胞增殖和细胞凋亡的影响.方法 不同浓度(0、10、20、40、80、160 mg/L)的OME作用于HepG2细胞后,分别于不同时间(24 h、48 h),采用甲基四唑蓝(MTT)法测定OME对HepG2细胞增殖的影响;5-乙炔基-2’-脱氧尿嘧啶核苷(Edu)荧光检测法测定DNA合成期(S期)细胞所占比例;Hoechst33342染色法检测细胞凋亡.结果 MTT结果示,10、20 mg/L OME对HepG2细胞增殖无明显抑制,而40、80、160 mg/L OME可产生明显抑制作用,其中80 mg/L OME作用最强;且相同浓度OME作用下,48 h较24 h对HepG2的抑制率增加.Edu荧光检测法表明,不同浓度OME处理细胞24h

  3. Genetic Control of the Trigger for the G2/M Checkpoint

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Eric J. [Columbia University; Smilenov, Lubomir B. [Columbia University; Young, Erik F. [Columbia University

    2013-10-01

    system, the engagement of the G2/M checkpoint only occurs at doses where most of the cells are bound for mitotic catastrophe. Further, compound haploinsufficiency of various radiosensitizing genes does not impact the threshold of activation. The experiments confirm a threshold of activation for the G2/M checkpoint, hinting at two separate radiation response programs acting below and above this threshold. Small RNA transfer in bystander effect biology: Small regulatory RNA molecules have now risen in prominence and utility. Specific examples are small interfering RNAs (siRNA) which are employed in cell level expression ablation projects and micro-RNAs (miRNA) which are a pool of short transcription products which serve to modulate the expression of other transcripts emerging from the genome in a meta-regulatory fine tuning of gene expression. The existing tenets of bystander effect radiation biology involve the communication of inflammatory mediators or direct intercellular communication of reactive oxygen/nitrogen species in cell-to-cell communicative organelles called gap junctions. By ablating gap junctions, reducing the ROS/inflammatory cytokine expression one can attenuate bystander effect signaling in cell culture systems. We hypothesized that miRNAs are a competent intercellular communication molecule and therefore a possible component of the bystander response. This view is supported by the observation that miRNA are secreted from cells in exosomes found in the circulation. This circulating pool reports disease type and severity in humans. We proposed use of microbeam irradiation technology at our facilities and enhancement of this capability with a new sorting technology which would allow us to sort irradiated and non-irradiated cells with absolute fidelity. Pursuing direct quantitative transfer assessment, we succeeded in designing and constructing a new add-on sorting appliance which harmonized with our existing instruments. The sorter allowed us to gently sort

  4. 龙葵碱诱导HepG2细胞凋亡的线粒体通路研究%Study on Mitochondrion Pathway of the Apoptosis of HepG2 Induced by Solanine

    Institute of Scientific and Technical Information of China (English)

    季宇彬; 高世勇

    2008-01-01

    目的 观察龙葵碱诱导HepG2细胞凋亡与线粒体通路的关系.方法 MTT法测定龙葵碱对HepG2细胞的细胞毒作用;AO/EB双染,激光共聚焦扫描显微镜观察龙葵碱对HepG2细胞形态学的影响;TMRE和Fluo-3/AM双染,激光共聚焦扫描显微镜同时观察细胞线粒体膜电位和细胞内[Ca2+];的变化.结果 龙葵碱对HepG2细胞有细胞毒作用;龙葵碱诱导HepG2细胞形态出现凋亡形态时TMRE和Fluo-3/AM双染观察表明,龙葵碱在降低线粒体膜电位的同时能够升高细胞内[Ca2+];浓度.结论 龙葵碱降低膜电位,开放细胞膜PT通道,使细胞内Ca2+顺浓度梯度转运,从而升高细胞内Ca2+浓度启动细胞凋亡机制.

  5. The preventive effects of natural adjuvants, G2 and G2F on tracheal responsiveness and serum IL-4 and IFN-γ (th1/th2 balance in sensitized guinea pigs

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Boskabady

    2014-07-01

    Full Text Available OBJECTIVE:The effects of natural adjuvants on lung inflammation and tracheal responsiveness were examined in sensitized guinea pigs.METHODS:The responses of guinea pig tracheal chains and the serum levels of interleukin-4 and interferon-gamma were examined in control pigs and three other groups of guinea pigs: the sensitized group and two other sensitized groups treated with either adjuvant G2 or adjuvant G2F (n = 7 for each group. Sensitization of the animals was achieved by injection and inhalation of ovalbumin.RESULTS:The results showed that sensitized animals had increased tracheal responsiveness and increased serum levels of interleukin-4 and interferon-gamma compared to controls (p<0.05 to p<0.001. Treatments with either G2 or G2F prevented the increase in tracheal responsiveness and serum interleukin-4 (p<0.01 to p<0.001. However, the serum levels of interferon-gamma and the interleukin-4-to-interferon-gamma ratio was increased in the treated groups (p<0.001 for all cases.CONCLUSIONS:These results indicate important preventive effects of two natural adjuvants, particularly G2, on the changes in tracheal responsiveness, serum cytokines and the interleukin-4-to-interferon-gamma ratio (T helper 1/T helper 2 balance in sensitized guinea pigs.

  6. Parkin induces G2/M cell cycle arrest in TNF-α-treated HeLa cells.

    Science.gov (United States)

    Lee, Min Ho; Cho, Yoonjung; Jung, Byung Chul; Kim, Sung Hoon; Kang, Yeo Wool; Pan, Cheol-Ho; Rhee, Ki-Jong; Kim, Yoon Suk

    2015-08-14

    Parkin is a known tumor suppressor. However, the mechanism by which parkin acts as a tumor suppressor remains to be fully elucidated. Previously, we reported that parkin expression induces caspase-dependent apoptotic cell death in TNF-α-treated HeLa cells. However, at that time, we did not consider the involvement of parkin in cell cycle control. In the current study, we investigated whether parkin is involved in cell cycle regulation and suppression of cancer cell growth. In our cell cycle analyses, parkin expression induced G2/M cell cycle arrest in TNF-α-treated HeLa cells. To elucidate the mechanism(s) by which parkin induces this G2/M arrest, we analyzed cell cycle regulatory molecules involved in the G2/M transition. Parkin expression induced CDC2 phosphorylation which is known to inhibit CDC2 activity and cause G2/M arrest. Cyclin B1, which is degraded during the mitotic transition, accumulated in response to parkin expression, thereby indicating parkin-induced G2/M arrest. Next, we established that Myt1, which is known to phosphorylate and inhibit CDC2, increased following parkin expression. In addition, we found that parkin also induces increased Myt1 expression, G2/M arrest, and reduced cell viability in TNF-α-treated HCT15 cells. Furthermore, knockdown of parkin expression by parkin-specific siRNA decreased Myt1 expression and phosphorylation of CDC2 and resulted in recovered cell viability. These results suggest that parkin acts as a crucial molecule causing cell cycle arrest in G2/M, thereby suppressing tumor cell growth.

  7. Berberine, a genotoxic alkaloid, induces ATM-Chk1 mediated G2 arrest in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yu; Liu Qiao; Liu Zhaojian; Li Boxuan; Sun Zhaoliang; Zhou Haibin; Zhang Xiyu; Gong Yaoqin [Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan (China); Shao Changshun, E-mail: changshun.shao@gmail.com [Ministry of Education Key Laboratory of Experimental Teratology and Institute of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan (China)

    2012-06-01

    Berberine has been shown to possess anti-tumor activity against a wide spectrum of cancer cells. It inhibits cancer cell proliferation by inducing cell cycle arrest, at G1 and/or G2/M, and apoptosis. While it has been documented that berberine induces G1 arrest by activating the p53-p21 cascade, it remains unclear what mechanism underlies the berberine-induced G2/M arrest, which is p53-independent. In this study, we tested the anti-proliferative effect of berberine on murine prostate cancer cell line RM-1 and characterized the underlying mechanisms. Berberine dose-dependently induced DNA double-strand breaks and apoptosis. At low concentrations, berberine was observed to induce G1 arrest, concomitant with the activation of p53-p21 cascade. Upon exposure to berberine at a higher concentration (50 {mu}M) for 24 h, cells exhibited G2/M arrest. Pharmacological inhibition of ATM by KU55933, or Chk1 by UCN-01, could efficiently abrogate the G2/M arrest in berberine-treated cells. Downregulation of Chk1 by RNA interference also abolished the G2/M arrest caused by berberine, confirming the role of Chk1 in the pathway leading to G2/M arrest. Abrogation of G2/M arrest by ATM inhibition forced more cells to undergo apoptosis in response to berberine treatment. Chk1 inhibition by UCN-01, on the other hand, rendered cells more sensitive to berberine only when p53 was inhibited. Our results suggest that combined administration of berberine and caffeine, or other ATM inhibitor, may accelerate the killing of cancer cells.

  8. Chromate Reductase YieF from Escherichia coli Enhances Hexavalent Chromium Resistance of Human HepG2 Cells

    Directory of Open Access Journals (Sweden)

    Xuan Liu

    2015-05-01

    Full Text Available Hexavalent chromium (Cr(VI is a serious environmental pollutant and human toxicant. Mammalian cells are very sensitive to chromate as they lack efficient chromate detoxifying strategy, e.g., chromate-reducing genes that are widely present in prokaryotes. To test whether introduction of prokaryotic chromate-reducing gene into mammalian cells could render higher chromate resistance, an Escherichia coli chromate-reducing gene yieF was transfected into human HepG2 cells. The expression of yieF was measured in stably transfected cells HepG2-YieF by quantitative RT-PCR and found up-regulated by 3.89-fold upon Cr(VI induction. In chromate-reducing ability test, HepG2-YieF cells that harbored the reductase showed significantly higher reducing ability of Cr(VI than HepG2 control cells. This result was further supported by the evidence of increased Cr(VI-removing ability of crude cell extract of HepG2-YieF. Moreover, HepG2-YieF demonstrated 10% higher viability and decreased expression of GSH synthesizing enzymes under Cr(VI stress. Subcellular localization of YieF was determined by tracing GFP-YieF fusion protein that was detected in both nucleus and cytoplasm by laser confocal microscopy. Altogether, this study successfully demonstrated that the expression of a prokaryotic Cr(VI-reducing gene yieF endowed mammalian cell HepG2 with enhanced chromate resistance, which brought new insight of Cr(VI detoxification in mammalian cells.

  9. Chromate Reductase YieF from Escherichia coli Enhances Hexavalent Chromium Resistance of Human HepG2 Cells.

    Science.gov (United States)

    Liu, Xuan; Wu, Gaofeng; Zhang, Yanli; Wu, Dan; Li, Xiangkai; Liu, Pu

    2015-05-26

    Hexavalent chromium (Cr(VI)) is a serious environmental pollutant and human toxicant. Mammalian cells are very sensitive to chromate as they lack efficient chromate detoxifying strategy, e.g., chromate-reducing genes that are widely present in prokaryotes. To test whether introduction of prokaryotic chromate-reducing gene into mammalian cells could render higher chromate resistance, an Escherichia coli chromate-reducing gene yieF was transfected into human HepG2 cells. The expression of yieF was measured in stably transfected cells HepG2-YieF by quantitative RT-PCR and found up-regulated by 3.89-fold upon Cr(VI) induction. In chromate-reducing ability test, HepG2-YieF cells that harbored the reductase showed significantly higher reducing ability of Cr(VI) than HepG2 control cells. This result was further supported by the evidence of increased Cr(VI)-removing ability of crude cell extract of HepG2-YieF. Moreover, HepG2-YieF demonstrated 10% higher viability and decreased expression of GSH synthesizing enzymes under Cr(VI) stress. Subcellular localization of YieF was determined by tracing GFP-YieF fusion protein that was detected in both nucleus and cytoplasm by laser confocal microscopy. Altogether, this study successfully demonstrated that the expression of a prokaryotic Cr(VI)-reducing gene yieF endowed mammalian cell HepG2 with enhanced chromate resistance, which brought new insight of Cr(VI) detoxification in mammalian cells.

  10. HCMV Activates the IL-6-JAK-STAT3 Axis in HepG2 Cells and Primary Human Hepatocytes

    Science.gov (United States)

    Kumar, Amit; Tripathy, Manoj K.; Herbein, Georges

    2013-01-01

    Objectives There has been increased interest in the possible role of human cytomegalovirus (HCMV) in carcinogenesis during the last decade. HCMV seroprevalence was enhanced in patients with hepatocellular carcinoma (HCC) but a possible relationship between HCC and HCMV infection remained to be assessed. The aim of this work was to investigate the pro-tumor influence of HCMV on primary human hepatocytes (PHH) and HepG2 cells. Methods Following infection of PHH and HepG2 cells by two different strains of HCMV, we measured the production of IL-6 in culture supernatants by ELISA and the protein levels of STAT3, pSTAT3, JAK, cyclin D1, survivin, p53, p21, and Mdm2 by western Blotting in infected and uninfected cells. Cell proliferation and transformation were investigated using Ki67Ag expression measurement and soft-agar colony formation assay respectively. Results Infection of HepG2 cells and PHH by HCMV resulted in the production of IL-6 and the subsequent activation of the IL-6R-JAK-STAT3 pathway. HCMV increased the expression of cyclin D1 and survivin. Cell proliferation was enhanced in HepG2 and PHH infected with HCMV, despite a paradoxical overexpression of p53 and p21. More importantly, we observed the formation of colonies in soft agar seeded with PHH infected with HCMV and when we challenged the HepG2 cultures to form tumorspheres, we found that the HCMV-infected cultures formed 2.5-fold more tumorspheres than uninfected cultures. Conclusion HCMV activated the IL-6-JAK-STAT3 pathway in PHH and HepG2 cells, favored cellular proliferation, induced PHH transformation and enhanced HepG2 tumorsphere formation. Our observations raise the possibility that HCMV infection might be involved in the genesis of hepatocellular carcinoma. PMID:23555719

  11. Enhancing effect of taurine on CYP7A1 mRNA expression in Hep G2 cells.

    Science.gov (United States)

    Lam, N V; Chen, W; Suruga, K; Nishimura, N; Goda, T; Yokogoshi, H

    2006-02-01

    Taurine has been reported to enhance cholesterol 7alpha-hydroxylase (CYP7A1) mRNA expression in animal models. However, no in vitro studies of this effect have been reported. The Hep G2 human hepatoma cell line has been recognized as a good model for studying the regulation of human CYP7A1. This work characterizes the effects of taurine on CYP7A1 mRNA levels of Hep G2 cells in a dose- and time-dependent manner. In the dose-dependent experiment, Hep G2 cells were treated with 0, 2, 10 or 20 mM taurine in the presence or absence of cholesterol 0.2 mM for 48 h. In the time-dependent experiment, Hep G2 cells were treated with 0 or 20 mM taurine for 4, 24 and 48 h with and without cholesterol 0.2 mM. Our data revealed that taurine showed time- and dose-response effects on CYP7A1 mRNA levels in Hep G2 cells. However, glycine - a structural analogue of taurine - did not have an effect on CYP7A1 gene expression. These results show that, in agreement to previous studies on animal models, taurine induces the mRNA levels of CYP7A1 in Hep G2 cells, which could enhance cholesterol conversion into bile acids. Also, Hep G2 cell line may be an appropriate model to study the effects of taurine on human cholesterol metabolism.

  12. [Experimental study on the immune response of fusion tumor vaccine of HepG2 and dendritic cells in vitro].

    Science.gov (United States)

    Pang, Y B; Cui, B Y; He, J; Huang, X P; Liang, W; Li, L Q; Luo, X L

    2017-02-21

    Objective: To estimate the immune response of HepG2/dendritic cell (DC) fusion cells vaccines against HepG2 cells in vitro. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy donors by Ficoll-Hypaque density-gradient centrifugation.Then DC were obtain from PBMCs by culturing in medium containing granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) for 5 days.DC and HepG2 fusion cells were induced by polythyleneglycol (PEG). The fusion cells were examined under fluorescence microscope by labeling DCs and HepG2 with green and red fluorescein, respectively, and then the fusion rates were analyzed by flow cytometry.The capacity of fusion cells to secrete interleukin (IL)-12 and stimulate the proliferation of T lymphocyte was assessed by ELISA and Flow cytometry, respectively.ELISPOT was used to assess the interferon gamma (IFN-γ) produced by cytotoxicity T lymphocyte (CTL), and the specific killing ability of fusion cells induce-CTL targeting HepG2 was estimated. Results: The fusion rate of HepG2/DC was 54.5%, and the fusion cells expressed a higher levels of DC mature marker CD80 and costimulatory molecules CD83, CD86 and MHC-Ⅰ, MHC-Ⅱ molecules HLA-ABC and HLA-DR than those in immature DCs (Pfusion cells could efficiently stimulate T lymphocytes to generate specific CTL targeting HepG2 cells.It might be a promising strategy of immunotherapy for HCC.

  13. 分泌型PTD4-Apoptin融合蛋白诱导HepG2细胞凋亡%Effect of Secretive PTD4-Apoptin Fusion Protein on Apoptosis of HepG2 Cells

    Institute of Scientific and Technical Information of China (English)

    陈庆; 杨辰苏; 陈虎; 陈道达; 龙跃平; 郑海

    2012-01-01

    Objective To investigate the effect of PTD4-Apoptin secreted by human umbilical venous endothelial cellsCHU-VECs)on apoptosis of HepG2 cells and the possible application for hepatocellular carcinoma gene therapy. Methods Recombi-nant plasmid of pSecTag2-PTD4-Apoptin was constructed and identified by restriction enzyme digestion analysis and DNA sequencing. HUVKCs were transiently transfected with pSecTag2-PTD4-Apoptin by lipofectamine and the culture supernatant was collected at 48 h after transfection. The expression and secretion of the PTD4-Apoptin fusion protein were detected by Western blot. HepG2 and L02 cells were co-cultured with the supernatant respectively. At 24 h after culture, the distribution of PTD4-Apoptin fusion protein in cells was detected by Western blot and apoptosis rate was measured by flow cytometry. Results The PTD4-Apoptin fusion protein secreted by pSecTag2-PTD4-Apoptin-transfected HUVECs could reenter adjacent untrans-fected HepG2 and L02 cells. The PTD4-Apoptin fusion protein could assemble in HepG2 nucleus and induce apoptosis of HepG2 cells(47. 4% ,P<0. 001). This effect was not detected in L02 cells. Conclusion The PTD4-Apoptin fusion protein secreted by pSecTag2-PTD4-Apoptin-transfected HUVECs can induce the apoptosis of adjacent untransfected HepG2 cells but not in L02 cells.%目的 研究分泌型的含蛋白质转导结构域的凋亡素(PTD4-Apoptin)融合基因经人脐静脉血管内皮细胞(HUVEC)表达和分泌后,对人肝癌HepG2细胞凋亡的影响,探讨其用于肝癌治疗的可能性.方法 构建PTD4-Apoptin融合基因的pSecTag2分泌型真核表达载体,并采用脂质体介导将其转染入HUVEC细胞,Western blot检测PTD4-Apoptin融合蛋白的表达及分泌,转染48 h后收集培养上清作为条件培养液,用于HepG2、L02细胞培养,共培养24 h后,采用Western blot检测细胞内和核内Apoptin的含量,流式细胞术检测细胞凋亡.结果 瞬时转染pSecTag2-PTD4-Apoptin

  14. 汉滩病毒囊膜糖蛋白g2基因重组腺病毒的构建与表达%Construction and expression of recombiant adenovirus carrying Hantaan virus glycoprotein G2 gene

    Institute of Scientific and Technical Information of China (English)

    吴兴安; 张芳琳; 于澜; 胡刚; 白文涛; 史梦远; 王海涛; 徐志凯

    2004-01-01

    获得汉滩病毒G2基因,构建其重组腺病毒并在HEK293细胞中包装表达,为研究汉滩病毒基因疫苗提供了实验基础.设计引物采用PCR从含汉滩病毒-76118株M基因的M56质粒扩增出糖蛋白G2基因片段,并将其克隆入腺病毒载体Adeno-X viral DNA,筛选获得重组腺病毒DNA,转染HEK293细胞,包装、扩增后得到汉滩病毒G2基因重组腺病毒原种;并在感染细胞内初步表达,用ELISA检测表达产物.得到了含汉滩病毒G2基因的重组腺病毒,其滴度约为1010pfu/mL,同时在感染的HEK293细胞中检测到汉滩病毒糖蛋白G2的表达.含汉滩病毒糖蛋白G2基因重组腺病毒的成功构建,为研究汉滩病毒基因疫苗提供了实验基础.

  15. Endoplasmic reticulum stress mediates sulforaphane-induced apoptosis of HepG2 human hepatocellular carcinoma cells.

    Science.gov (United States)

    Zou, Xiang; Qu, Zhongyuan; Fang, Yueni; Shi, Xin; Ji, Yubin

    2017-01-01

    Sulforaphane (SFN) is a naturally occurring chemopreventive agent, which effectively inhibits proliferation of HepG2 human hepatocellular carcinoma cells via mitochondria‑mediated apoptosis. Endoplasmic reticulum stress is considered the most important cause of cell apoptosis; therefore, the present study aimed to determine whether the endoplasmic reticulum pathway was involved in SFN-induced apoptosis of HepG2 cells. An MTT assay was used to detect the inhibitory effects of SFN on HepG2 cells. Fluorescence microscopy was used to observe the morphological changes in apoptotic cells, and western blot analysis was conducted to detect the expression of binding immunoglobulin protein (Bip)/glucose-regulated protein 78 (GRP78), X‑box binding protein‑1 (XBP‑1) and BH3 interacting domain death agonist (Bid). Furthermore, flow cytometry was used to determine the apoptotic rate of HepG2 cells, and the protein expression of C/EBP homologous protein (CHOP)/growth arrest‑ and DNA damage‑inducible gene 153 (GADD153) and caspase-12 in HepG2 cells. The results indicated that SFN significantly inhibited the proliferation of HepG2 cells; the half maximal inhibitory concentration values were 32.03±0.96, 20.90±1.96 and 13.87±0.44 µmol/l, following treatment with SFN for 24, 48 and 72 h, respectively. Following 48 h of SFN treatment (10, 20 and 40 µmol/l), the apoptotic rates of HepG2 cells were 31.8, 61.3 and 77.1%, respectively. Furthermore, after 48 h of exposure to SFN, the cells presented typical morphological alterations of apoptosis, as detected under fluorescence microscopy. Treatment with SFN for 48 h also significantly upregulated the protein expression levels of Bip/GRP78, XBP‑1, caspase‑12, CHOP/GADD153 and Bid in HepG2 cells. In conclusion, endoplasmic reticulum stress may be considered the most important mechanism underlying SFN-induced apoptosis in HepG2 cells.

  16. 免疫初乳中IgG1和IgG2的分离纯化%Isolation and purification of IgG1 and IgG2 from immune colostrum

    Institute of Scientific and Technical Information of China (English)

    张和平; 李立民; 孙天松; 郭军

    2001-01-01

    采用硫酸胺盐析、DE-52离子交换色谱、Sephacryl S-100凝胶过滤色谱从免疫初乳分离纯化出了IgG1和IgG2,经SDS-PAGE电泳及免疫电泳证实为纯品;并对IgG1和IgG2的抗体凝集价进行了测定.

  17. Relationship between radiation-induced cell death (apoptosis) and protective G2/M arrest in human cells; Der Zusammenhang von strahleninduziertem Zelltod (Apoptose) und dem protektiven G2/M Arrest in menschlichen Zellen

    Energy Technology Data Exchange (ETDEWEB)

    Dornreiter, I. [Heinrich-Pette-Institut fuer Experimentelle Virologie und Immunologie, Hamburg (Germany)

    2006-07-01

    For the first time investigations revealed that induction of double stand brakes (DSBs) at the G1/S-transition, a cell cycle position prior to the onset of DNA replication, activates the intra- S- and G2-checkpoint. The sequential activation of the checkpoints first enables the nonhomologous end joining repair mechanism (NHEJ), which allows quick repair of damaged DNA before DNA replication is initiated, and second the more accurate homologous recombination repair mechanism (HDR) after the genome is duplicated. HDR may play a dominant role in the repair of DNA DSBs, however this role depends on duplicated chromosomes and accordingly on the cell cycle phase. Thus, the results explain why the G2- checkpoint is always activated when cells are damaged in G1, G1/S or early S. While the ATM-mediated intra-S-checkpoint depends on the transcriptionally active Aep53, a recently discovered p53-splice variant, activation of the ATM/ATR-mediated G2-checkpoint is independent of functional p53 and Aep53. The damage induced ATM/ATR-phosphorylation cascade leads to inhibition of the Cdk1-activating phosphatase Cdc25C and consequently to inhibition of the mitosis promoting factor cyclin B-Cdk1. Additional experiments demonstrated that lethal damage converts the temporary G2-checkpoint into a permanent G2- arrest, also termed G2-exit, which depends on the p53 status of the damaged cell. In wtp53 cells, the G2-exit is mediated by complex formation of phosphorylated cyclin B-Cdk1 with the p53-induced Cdk-inhibitor p21 and the p53-dependent inhibition of cyclin B and Cdk1 transcription. Furthermore, in severely damaged wtp53 cells, loss of functional wtp53 results in abrogation of the G2-arrest and additionally promotes uncoupling of S-phase and mitosis, as demonstrated by the formation of polyploid cells. Hence, it appears that the coordinated activity of p53 and Aep53 is essential for the cellular reaction provoked by DNA damage and thus determines the faith of the damaged cell

  18. Mechanism of Arctigenin-Induced Specific Cytotoxicity against Human Hepatocellular Carcinoma Cell Lines: Hep G2 and SMMC7721.

    Directory of Open Access Journals (Sweden)

    Zheng Lu

    Full Text Available Arctigenin (ARG has been previously reported to exert high biological activities including anti-inflammatory, antiviral and anticancer. In this study, the anti-tumor mechanism of ARG towards human hepatocellular carcinoma (HCC was firstly investigated. We demonstrated that ARG could induce apoptosis in Hep G2 and SMMC7721 cells but not in normal hepatic cells, and its apoptotic effect on Hep G2 was stronger than that on SMMC7721. Furthermore, the following study showed that ARG treatment led to a loss in the mitochondrial out membrane potential, up-regulation of Bax, down-regulation of Bcl-2, a release of cytochrome c, caspase-9 and caspase-3 activation and a cleavage of poly (ADP-ribose polymerase in both Hep G2 and SMMC7721 cells, suggesting ARG-induced apoptosis was associated with the mitochondria mediated pathway. Moreover, the activation of caspase-8 and the increased expression levels of Fas/FasL and TNF-α revealed that the Fas/FasL-related pathway was also involved in this process. Additionally, ARG induced apoptosis was accompanied by a deactivation of PI3K/p-Akt pathway, an accumulation of p53 protein and an inhibition of NF-κB nuclear translocation especially in Hep G2 cells, which might be the reason that Hep G2 was more sensitive than SMMC7721 cells to ARG treatment.

  19. Mechanism of Arctigenin-Induced Specific Cytotoxicity against Human Hepatocellular Carcinoma Cell Lines: Hep G2 and SMMC7721.

    Science.gov (United States)

    Lu, Zheng; Cao, Shengbo; Zhou, Hongbo; Hua, Ling; Zhang, Shishuo; Cao, Jiyue

    2015-01-01

    Arctigenin (ARG) has been previously reported to exert high biological activities including anti-inflammatory, antiviral and anticancer. In this study, the anti-tumor mechanism of ARG towards human hepatocellular carcinoma (HCC) was firstly investigated. We demonstrated that ARG could induce apoptosis in Hep G2 and SMMC7721 cells but not in normal hepatic cells, and its apoptotic effect on Hep G2 was stronger than that on SMMC7721. Furthermore, the following study showed that ARG treatment led to a loss in the mitochondrial out membrane potential, up-regulation of Bax, down-regulation of Bcl-2, a release of cytochrome c, caspase-9 and caspase-3 activation and a cleavage of poly (ADP-ribose) polymerase in both Hep G2 and SMMC7721 cells, suggesting ARG-induced apoptosis was associated with the mitochondria mediated pathway. Moreover, the activation of caspase-8 and the increased expression levels of Fas/FasL and TNF-α revealed that the Fas/FasL-related pathway was also involved in this process. Additionally, ARG induced apoptosis was accompanied by a deactivation of PI3K/p-Akt pathway, an accumulation of p53 protein and an inhibition of NF-κB nuclear translocation especially in Hep G2 cells, which might be the reason that Hep G2 was more sensitive than SMMC7721 cells to ARG treatment.

  20. A plant-specific cyclin-dependent kinase is involved in the control of G2/M progression in plants.

    Science.gov (United States)

    Porceddu, A; Stals, H; Reichheld, J P; Segers, G; De Veylder, L; Barroco, R P; Casteels, P; Van Montagu, M; Inzé, D; Mironov, V

    2001-09-28

    Cyclin-dependent kinases (CDKs) control the key transitions in the eukaryotic cell cycle. All the CDKs known to control G(2)/M progression in yeast and animals are distinguished by the characteristic PSTAIRE motif in their cyclin-binding domain and are closely related. Higher plants contain in addition a number of more divergent non-PSTAIRE CDKs with still obscure functions. We show that a plant-specific type of non-PSTAIRE CDKs is involved in the control of the G(2)/M progression. In synchronized tobacco BY-2 cells, the corresponding protein, accumulated in a cell cycle-regulated fashion, peaking at the G(2)/M transition. The associated histone H1 kinase activity reached a maximum in mitosis and required a yet unidentified subunit to be fully active. Down-regulation of the associated kinase activity in transgenic tobacco plants using a dominant-negative mutation delayed G(2)/M transition. These results provide the first evidence that non-PSTAIRE CDKs are involved in the control of the G(2)/M progression in plants.

  1. The microtubule cytoskeleton is required for a G2 cell cycle delay in cancer cells lacking stathmin and p53.

    Science.gov (United States)

    Carney, Bruce K; Caruso Silva, Victoria; Cassimeris, Lynne

    2012-05-01

    In several cancer cell lines, depleting the microtubule (MT)-destabilizing protein stathmin/oncoprotein18 leads to a G2 cell cycle delay and apoptosis. These phenotypes are observed only in synergy with low levels of p53, but the pathway(s) activated by stathmin depletion to delay the cell cycle are unknown. We found that stathmin depletion caused greater MT stability in synergy with loss of p53, measured by the levels of acetylated α-tubulin and the rate of centrosomal MT nucleation. Nocodazole or vinblastine-induced MT depolymerization abrogated the stathmin-depletion induced G2 delay, measured by the percentage of cells staining positive for several markers (TPX2, CDK1 with inhibitory phosphorylation), indicating that MTs are required to lengthen G2. Live cell imaging showed that stathmin depletion increased time in G2 without an impact on the duration of mitosis, indicating that the longer interphase duration is not simply a consequence of a previous slowed mitosis. In contrast, stabilization of MTs with paclitaxel (8 nM) slowed mitosis without lengthening the duration of interphase, demonstrating that increased MT stability alone is not sufficient to delay cells in G2.

  2. Selection of scFvs specific for the HepG2 cell line using ribosome display

    Indian Academy of Sciences (India)

    Lei Zhou; Wei-Ping Mao; Juan Fen; Hong-Yun Liu; Chuan-Jing Wei; Wen-Xiu Li; Feng-Yun Zhou

    2009-06-01

    The aim of this study was to construct a ribosome display library of single chain variable fragments (scFvs) associated with hepatocarcinoma and screen such a library for hepatocarcinoma-binding scFvs. mRNA was isolated from the spleens of mice immunized with hepatocellular carcinoma cell line HepG2. Heavy and k chain genes (VH and k) were amplified separately by RT-PCR, and an anti-HepG2 VH/k chain ribosome display library was constructed by assembling VH and k into the VH/k chain with a specially constructed linker by SOE-PCR. The VH/k chain library was transcribed and translated in vitro using a rabbit reticulocyte lysate system. In order to isolate specific scFvs, recognizing HepG2 negative selection on a normal hepatocyte line WRL-68 was carried out before three rounds of positive selection on HepG2. After three rounds of panning, cell enzyme-linked immunosorbent assay (ELISA) showed that one of the scFvs had high affinity for the HepG2 cell and lower affinity for the WRL-68 cell. In this study, we successfully constructed a native ribosome display library. Such a library would prove useful for direct intact cell panning using ribosome display technology. The selected scFv had a potential value for hepatocarcinoma treatment.

  3. Effect of baicalin-copper on the induction of apoptosis in human hepatoblastoma cancer HepG2 cells.

    Science.gov (United States)

    Li, Xiaoli; Zou, Kaili; Gou, Jing; Du, Qin; Li, Dejuan; He, Xiaoyan; Li, Zhubo

    2015-03-01

    The medical properties of baicalin have been well known for many years. However, the discovery that baicalin in the presence of metal ions is more effective than baicalin alone changed the course of drug research. The present study was designed to investigate the effect and possible mechanism of apoptosis induced by baicalin-copper in a human hepatoblastoma cancer cell line (HepG2) and in vivo. This study demonstrated that baicalin-copper suppresses the proliferation of HepG2 cells in a dose-dependent manner. Intraperitoneal injection of baicalin-copper resulted in a significant decrease in tumor growth in xenografts in nude mice. Acridine orange staining and flow cytometry analysis demonstrated that baicalin-copper induced apoptosis in HepG2 cells and caused cells to arrest in G2-M phase of the cell cycle. Furthermore, baicalin-copper treatment significantly increased the Bax/Bcl-2 ratio and p38 levels, as well as decreased the expression of caspase-3, p-PI3K, p-Akt and p-mTOR (P copper induces apoptosis in HepG2 cells by down-regulating the PI3K/Akt/mTOR signaling pathway.

  4. The role of alkaline phosphatase in intracellular lipid accumulation in the human hepatocarcinoma cell line, HepG2.

    Science.gov (United States)

    Chirambo, George M; van Niekerk, Chantal; Crowther, Nigel J

    2017-04-01

    Inhibition of tissue non-specific alkaline phosphatase (TNALP) decreases intracellular lipid accumulation in human preadipocytes and the murine preadipocyte cell line, 3T3-L1. Therefore, the current study was performed to determine if TNALP is required for intracellular lipid deposition in the human hepatocyte cell line, HepG2. Intracellular lipid accumulation, TNALP activity and peroxisome proliferator activated receptor (PPAR) γ gene expression were measured in HepG2 and 3T3-L1 cells in the presence and absence of the TNALP inhibitors levamisole and histidine. Sub-cellular TNALP activity was localized using cytochemical analysis. Both PPARγ gene expression and TNALP activity increased during intracellular lipid accumulation in HepG2 and 3T3-L1 cells. Inhibition of TNALP blocked intracellular lipid accumulation but did not alter expression of the PPARγ gene. In HepG2 cells, TNALP co-localized with adipophilin on the lipid droplet membrane. These data suggest a role for TNALP in lipid droplet formation, possibly downstream from PPARγ, within HepG2 and 3T3-L1 cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Upgrading HepG2 cells with adenoviral vectors that encode drug-metabolizing enzymes: application for drug hepatotoxicity testing.

    Science.gov (United States)

    Gómez-Lechón, M José; Tolosa, Laia; Donato, M Teresa

    2017-02-01

    Drug attrition rates due to hepatotoxicity are an important safety issue considered in drug development. The HepG2 hepatoma cell line is currently being used for drug-induced hepatotoxicity evaluations, but its expression of drug-metabolizing enzymes is poor compared with hepatocytes. Different approaches have been proposed to upgrade HepG2 cells for more reliable drug-induced liver injury predictions. Areas covered: We describe the advantages and limitations of HepG2 cells transduced with adenoviral vectors that encode drug-metabolizing enzymes for safety risk assessments of bioactivable compounds. Adenoviral transduction facilitates efficient and controlled delivery of multiple drug-metabolizing activities to HepG2 cells at comparable levels to primary human hepatocytes by generating an 'artificial hepatocyte'. Furthermore, adenoviral transduction enables the design of tailored cells expressing particular metabolic capacities. Expert opinion: Upgraded HepG2 cells that recreate known inter-individual variations in hepatic CYP and conjugating activities due to both genetic (e.g., polymorphisms) or environmental (e.g., induction, inhibition) factors seems a suitable model to identify bioactivable drug and conduct hepatotoxicity risk assessments. This strategy should enable the generation of customized cells by reproducing human pheno- and genotypic CYP variability to represent a valuable human hepatic cell model to develop new safer drugs and to improve existing predictive toxicity assays.

  6. Effects of nitric oxide on the biological behavior of HepG2 human hepatocellular carcinoma cells.

    Science.gov (United States)

    Zhou, Lei; Zhang, Heng; Wu, Jie

    2016-05-01

    Many studies have found the function of nitric oxide (NO) in cancer as a pro-neoplastic vs. an anti-neoplastic effector, but the role of NO in hepatocellular carcinoma (HCC) remains unclear. The present study aimed to investigate the effects of nitric oxide (NO) on the biological behavior of the human hepatocellular carcinoma cell line HepG2. HepG2 cell was cultured in vitro and treated with or without sodium nitroprusside (SNP), a NO donor. Subsequently, we evaluated the effects of NO in cell proliferation, cell cycle, apoptosis, migration and invasion by MTT assay, flow cytometry, wound healing assay and Matrigel invasion assay. We demonstrate that NO significantly inhibited HepG2 cell proliferation by inducing G0/G1 phase arrest in a dose-dependent manner. In addition, compared to the control group, cells treated with SNP showed obviously higher apoptosis ratios in a dose-dependent manner. Furthermore, we revealed that NO effectively inhibited the ability of migration and invasion of HepG2 cells. Taken together, our results suggested that NO has an important role in the regulation of biological behavior in HepG2 cells and the potential for use in the prevention and treatment of HCC.

  7. Enhancement of amygdalin activated with β-D-glucosidase on HepG2 cells proliferation and apoptosis.

    Science.gov (United States)

    Zhou, Cunshan; Qian, Lichun; Ma, Haile; Yu, Xiaojie; Zhang, Youzuo; Qu, Wenjuan; Zhang, Xiaoxu; Xia, Wei

    2012-09-01

    The growth inhibition and induction of apoptosis brought by amygdalin and activated with β-D-glucosidase were tested for cytoactivity in HepG2 cells. The MTT viability assay showed that all samples had effects on HepG2 proliferation in dose and time response manners. IC50 of stand-alone amygdalin and activation with β-D-glucosidase on the proliferation of HepG2 cells for 48 h were 458.10 mg/mL and 3.2 mg/mL, respectively. Moreover, apoptotic cells were determined by AO/EB (acridine orange/ethidium bromide) fluorescent staining method and Annexin V-FITC/PI staining flow cytometry cell cycle analysis. With increasing of amygdalin concentration and the incubation time, the apoptotic rate was heightened. Compared with the control, there was significant difference (pamygdalin had no strong anti-HepG2 activity; however the ingredients of amygdalin activated with β-D-glucosidase had a higher and efficient anti-HepG2 activity. It was therefore suggested that this combination strategy may be applicable for treating tumors with a higher activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. BDNF表达下调抑制HepG2细胞侵袭的相关分子机制研究%Down-regulation of BDNF suppressed invasion of HepG2 cells and associated molecular mechanisms

    Institute of Scientific and Technical Information of China (English)

    郭大伟; 侯学忠; 孙文郁; 朱磊; 张弘彬; 姜晓峰; 梁健

    2012-01-01

    Objective: To investigate the effects of siRNA specificly for BDNF on apoptosis and invasion of HepG2 cells and its potential molecular mechanism. Methods; The expression of BDNF in cells was examined by western blot and BDNF secretion was evaluated by ELISA in human HCC cell lines of HepG2. BDNF knockdown was performed by specific BDNF - siRNA transfection in HepG2 cells, actin cytoskelelon was shown by FITC - phalloidin staining and the activations of RhoA, Racl or Cdc42 were determined by Western blot. Cell apoptosis and invasion were examined by flow cytometry and transwell assay respectively. Results: The expression of BDNF was found in HepG2 cells. BDNF concentration in the supernatant of HepG2 cells was 88.56 ±7.45 pg/ml. Inhibited expression of BDNF by specific siRNA showed impaired actin polymerization and decreased activations of RhoA or Racl in HepG2 cells. BDNF knockdown also induced apoptosis and suppressed invasion of HepG2 cells. Conclusion: BDNF knockdown inhibited cell invasion probably through the blocked actin polymerization and the correlated inactivation of RhoA or Racl. Aiming at BDNF/TrkB signaling interruption may be an effective strategy to prevent HCC progression.%目的:应用特异性siRNA下调HepG2细胞中BDNF表达,观察对细胞凋亡和侵袭的影响并探讨相关分子机制.方法:在人HCC细胞系HepG2中,采用Western blot方法检测BDNF的表达,采用ELISA方法检测培养液上清BDNF的分泌水平.特异性BDNF-siRNA转染细胞,采用FITC-phalloidin染色方法检测actin 细胞骨架的变化,采用Western blot方法检测细胞内RhoA、Rac1、Cdc42的活化情况.同时,流式细胞术检测细胞凋亡,Transwell小室测定细胞侵袭能力的变化.结果:HepG2细胞培养上清中BDNF含量为88.56±7.45 pg/ml.在HepG2细胞中,特异性BDNF-siRNA显著抑制BDNF的表达,干扰细胞内actin细胞骨架聚合,RhoA或Racl活性受到抑制,同时凋亡细胞数增加、细胞侵袭能力下降.结论:干

  9. Inflammation response at the transcriptional level of HepG2 cells induced by multi-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Piret, Jean-Pascal; Vankoningsloo, Sebastien; Noel, Florence; Saout, Christelle; Toussaint, Olivier [Research Unit in Cellular Biology (URBC), Narilis, University of Namur, 5000 Namur (Belgium); Mendoza, Jorge Mejia; Lucas, Stephane, E-mail: olivier.toussaint@fundp.ac.be [Research Center for the Physics of Matter and Radiation (PMR), Narilis, University of Namur, 5000 Namur (Belgium)

    2011-07-06

    Poor information are currently available about the biological effects of multi-walled carbon nanotubes (MWCNT) on the liver. In this study, we evaluated the effects of MWCNT at the transcriptional level on the classical in vitro model of HepG2 hepatocarcinoma cells. The expression levels of 96 transcript species implicated in the inflammatory and immune responses was studied after a 24h incubation of HepG2 cells in presence of raw MWCNT dispersed in water by stirring. Among the 46 transcript species detected, only a few transcripts including mRNA coding for interleukine-7, chemokines receptor of the C-C families CCR7, as well as Endothelin-1, were statistically more abundant after treatment with MWCNT. Altogether, these data indicate that MWCNT can only induce a weak inflammatory response in HepG2 cells.

  10. Inflammation response at the transcriptional level of HepG2 cells induced by multi-walled carbon nanotubes

    Science.gov (United States)

    Piret, Jean-Pascal; Vankoningsloo, Sébastien; Noël, Florence; Mejia Mendoza, Jorge; Lucas, Stéphane; Saout, Christelle; Toussaint, Olivier

    2011-07-01

    Poor information are currently available about the biological effects of multi-walled carbon nanotubes (MWCNT) on the liver. In this study, we evaluated the effects of MWCNT at the transcriptional level on the classical in vitro model of HepG2 hepatocarcinoma cells. The expression levels of 96 transcript species implicated in the inflammatory and immune responses was studied after a 24h incubation of HepG2 cells in presence of raw MWCNT dispersed in water by stirring. Among the 46 transcript species detected, only a few transcripts including mRNA coding for interleukine-7, chemokines receptor of the C-C families CCR7, as well as Endothelin-1, were statistically more abundant after treatment with MWCNT. Altogether, these data indicate that MWCNT can only induce a weak inflammatory response in HepG2 cells.

  11. Induction of apoptosis in human liver carcinoma HepG2 cell line by 5-allyl-7-gen-difluoromethylenechrysin

    Institute of Scientific and Technical Information of China (English)

    Xiang-Wen Tan; Hong Xia; Jin-Hua Xu; Jian-Guo Cao

    2009-01-01

    AIM: To investigate the effect of 5-allyl-7-gen-difluoromethylenechrysin (ADFMChR) on apoptosis of human liver carcinoma HepG2 cell line and the molecular mechanisms involved. METHODS: HepG2 cells and L-02 cells were cultured in vitro and the inhibitory effect of ADFMChR on their proliferation was measured by MTT assay. The apoptosis of HepG2 cells was determined by flow cytometry (FCM) using propidium iodide (PI) fluorescence staining.DNA ladder bands were observed by DNA agarose gel electrophoresis. The influence of ADFMChR on the proxisome proliferator-activated receptor γ (PPARγ), NF-κB, Bcl-2 and Bax protein expression of HepG2 cells were analyzed by Western blotting. RESULTS: MTT assay showed that ADFMChR significantly inhibited proliferation of HepG2 cells in a dosedependent manner, with little effect on growth of L-02 cells, and when IC50 was measured as 8.45 μmol/L and 191.55 μmol/L respectively, the potency of ADFMChR to HepG2 cells, was found to be similar to 5-fluorouracil (5-FU, IC50 was 9.27 μmol/L). The selective index of ADFMChR cytotoxicity to HepG2 cells was 22.67 (191.55/8.45), higher than 5-FU (SI was 7.05 (65.37/9.27). FCM with PI staining demonstrated that the apoptosis rates of HepG2 cells treated with 3.0, 10.0 and 30.0 μmol/L ADFMChR for 48 h were 5.79%, 9.29% and 37.8%, respectively, and were significantly higher when treated with 30.0 μmol/L ADFMChR than when treated with 30.0 μmol/L ChR (16.0%) ( P < 0.05) and were similar to those obtained with 30.0 μmol/L 5-FU (41.0%). DNA agarose gel electrophoresis showed that treatment of HepG2 cells with 10.0 μmol/L ADFMChR for 48 h and 72 h resulted in typical DNA ladders which could be reversed by 10.00 μmol/L GW9662, a blocker of PPARγ. Western blotting analysis revealed that after 24 h of treatment with 3.0, 10.0, 30.0 μmol/L ADFMChR, PPARγ and Bax protein expression in HepG2 cells increased but Bcl-2 and NF-κB expression decreased; however, pre-incubation with 10.0 μmol/L GW

  12. Measurement of the virtual-photon asymmetry A2 and the spin-structure function g2 of the proton

    CERN Document Server

    Airapetian, A; Akopov, Z; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetissian, A; Avetisyan, E; Belostotski, S; Bianchi, N; Blok, H P; Borissov, A; Bowles, J; Bryzgalov, V; Burns, J; Capiluppi, M; Capitani, G P; Cisbani, E; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; Deconinck, W; De Leo, R; De Nardo, L; De Sanctis, E; Diefenthaler, M; Di Nezza, P; Düren, M; Ehrenfried, M; Elbakian, G; Ellinghaus, F; Fantoni, A; Felawka, L; Frullani, S; Gabbert, D; Gapienko, G; Gapienko, V; Garibaldi, F; Gavrilov, G; Gharibyan, V; Giordano, F; Gliske, S; Golembiovskaya, M; Hadjidakis, C; Hartig, M; Hillenbrand, A; Hoek, M; Holler, Y; Hristova, I; Imazu, Y; Ivanilov, A; Jackson, H E; Jo, H S; Joosten, S; Kaiser, R; Karyan, G; Keri, T; Kinney, E; Kisselev, A; Korotkov, V; Kozlov, V; Kravchenko, P; Krivokhijine, V G; Lagamba, L; Lapikás, L; Lehmann, I; Lenisa, P; Ruiz, A López; Lorenzon, W; Ma, B -Q; Mahon, D; Makins, N C R; Manaenkov, S I; Manfré, L; Mao, Y; Marianski, B; de la Ossa, A Martinez; Marukyan, H; Miller, C A; Miyachi, Y; Movsisyan, A; Muccifora, V; Murray, M; Mussgiller, A; Nappi, E; Naryshkin, Y; Nass, A; Negodaev, M; Nowak, W -D; Pappalardo, L L; Perez-Benito, R; Petrosyan, A; Reimer, P E; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubin, J; Ryckbosch, D; Salomatin, Y; Sanftl, F; Schäfer, A; Schnell, G; Schüler, K P; Seitz, B; Shibata, T -A; Shutov, V; Stancari, M; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stinzing, F; Taroian, S; Terkulov, A; Truty, R; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van Haarlem, Y; Van Hulse, C; Veretennikov, D; Vikhrov, V; Vilardi, I; Wang, S; Yaschenko, S; Ye, Z; Yen, S; Zagrebelnyy, V; Zeiler, D; Zihlmann, B; Zupranski, P

    2011-01-01

    A measurement of the virtual-photon asymmetry A_2(x,Q^2) and of the spin-structure function g_2(x,Q^2) of the proton are presented for the kinematic range 0.004 < x < 0.9 and 0.18 GeV^2 < Q^2 < 20 GeV^2. The data were collected by the HERMES experiment at the HERA storage ring at DESY while studying inclusive deep-inelastic scattering of 27.6 GeV longitudinally polarized leptons off a transversely polarized hydrogen gas target. The results are consistent with previous experimental data from CERN and SLAC. For the x-range covered, the measured integral of g_2(x) converges to the null result of the Burkhardt-Cottingham sum rule. The x^2 moment of the twist-3 contribution to g_2(x) is found to be compatible with zero.

  13. Phospho-Bcl-x(L)(Ser62) plays a key role at DNA damage-induced G(2) checkpoint.

    Science.gov (United States)

    Wang, Jianfang; Beauchemin, Myriam; Bertrand, Richard

    2012-06-01

    Accumulating evidence suggests that Bcl-xL, an anti-apoptotic member of the Bcl-2 family, also functions in cell cycle progression and cell cycle checkpoints. Analysis of a series of phosphorylation site mutants reveals that cells expressing Bcl-xL(Ser62Ala) mutant are less stable at the G 2 checkpoint and enter mitosis more rapidly than cells expressing wild-type Bcl-xL or Bcl-xL phosphorylation site mutants, including Thr41Ala, Ser43Ala, Thr47Ala, Ser56Ala and Thr115Ala. Analysis of the dynamic phosphorylation and location of phospho-Bcl-xL(Ser62) in unperturbed, synchronized cells and during DNA damage-induced G 2 arrest discloses that a pool of phospho-Bcl-xL(Ser62) accumulates into nucleolar structures in etoposide-exposed cells during G 2 arrest. In a series of in vitro kinase assays, pharmacological inhibitors and specific siRNAs experiments, we found that Polo kinase 1 and MAPK9/JNK2 are major protein kinases involved in Bcl-xL(Ser62) phosphorylation and accumulation into nucleolar structures during the G 2 checkpoint. In nucleoli, phospho-Bcl-xL(Ser62) binds to and co-localizes with Cdk1(cdc2), the key cyclin-dependent kinase required for entry into mitosis. These data indicate that during G 2 checkpoint, phospho-Bcl-xL(Ser62) stabilizes G 2 arrest by timely trapping of Cdk1(cdc2) in nucleolar structures to slow mitotic entry. It also highlights that DNA damage affects the dynamic composition of the nucleolus, which now emerges as a piece of the DNA damage response.

  14. Development and Event-specific Detection of Transgenic Glyphosate-resistant Rice Expressing the G2-EPSPS Gene.

    Science.gov (United States)

    Dong, Yufeng; Jin, Xi; Tang, Qiaoling; Zhang, Xin; Yang, Jiangtao; Liu, Xiaojing; Cai, Junfeng; Zhang, Xiaobing; Wang, Xujing; Wang, Zhixing

    2017-01-01

    Glyphosate is a widely used herbicide, due to its broad spectrum, low cost, low toxicity, high efficiency, and non-selective characteristics. Rice farmers rarely use glyphosate as a herbicide, because the crop is sensitive to this chemical. The development of transgenic glyphosate-tolerant rice could greatly improve the economics of rice production. Here, we transformed the Pseudomonas fluorescens G2 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) gene G2-EPSPS, which conferred tolerance to glyphosate herbicide into a widely used japonica rice cultivar, Zhonghua 11 (ZH11), to develop two highly glyphosate-tolerant transgenic rice lines, G2-6 and G2-7, with one exogenous gene integration. Seed germination tests and glyphosate-tolerance assays of plants grown in a greenhouse showed that the two transgenic lines could greatly improve glyphosate-tolerance compared with the wild-type; The glyphosate-tolerance field test indicated that both transgenic lines could grow at concentrations of 20,000 ppm glyphosate, which is more than 20-times the recommended concentration in the field. Isolation of the flanking sequence of transgenic rice G2-6 indicated that the 5'-terminal of T-DNA was inserted into chromosome 8 of the rice genome. An event-specific PCR test system was established and the limit of detection of the primers reached five copies. Overall, the G2-EPSPS gene significantly improved glyphosate-tolerance in transgenic rice; furthermore, it is a useful candidate gene for the future development of commercial transgenic rice.

  15. HIV-1 Vpr-mediated G2 arrest involves the DDB1-CUL4AVPRBP E3 ubiquitin ligase.

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Belzile

    2007-07-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 viral protein R (Vpr has been shown to cause G2 cell cycle arrest in human cells by inducing ATR-mediated inactivation of p34cdc2, but factors directly engaged in this process remain unknown. We used tandem affinity purification to isolate native Vpr complexes. We found that damaged DNA binding protein 1 (DDB1, viral protein R binding protein (VPRBP, and cullin 4A (CUL4A--components of a CUL4A E3 ubiquitin ligase complex, DDB1-CUL4A(VPRBP--were able to associate with Vpr. Depletion of VPRBP by small interfering RNA impaired Vpr-mediated induction of G2 arrest. Importantly, VPRBP knockdown alone did not affect normal cell cycle progression or activation of ATR checkpoints, suggesting that the involvement of VPRBP in G2 arrest was specific to Vpr. Moreover, leucine/isoleucine-rich domain Vpr mutants impaired in their ability to interact with VPRBP and DDB1 also produced strongly attenuated G2 arrest. In contrast, G2 arrest-defective C-terminal Vpr mutants were found to maintain their ability to associate with these proteins, suggesting that the interaction of Vpr with the DDB1-VPRBP complex is necessary but not sufficient to block cell cycle progression. Overall, these results point toward a model in which Vpr could act as a connector between the DDB1-CUL4A(VPRBP E3 ubiquitin ligase complex and an unknown cellular factor whose proteolysis or modulation of activity through ubiquitination would activate ATR-mediated checkpoint signaling and induce G2 arrest.

  16. GRK2 negatively regulates IGF-1R signaling pathway and cyclins' expression in HepG2 cells.

    Science.gov (United States)

    Wei, Zhengyu; Hurtt, Reginald; Gu, Tina; Bodzin, Adam S; Koch, Walter J; Doria, Cataldo

    2013-09-01

    G protein coupled receptor kinase 2 (GRK2) plays a central role in the regulation of a variety of important signaling pathways. Alternation of GRK2 protein level and activity casts profound effects on cell physiological functions and causes diseases such as heart failure, rheumatoid arthritis, and obesity. We have previously reported that overexpression of GRK2 has an inhibitory role in cancer cell growth. To further examine the role of GRK2 in cancer, in this study, we investigated the effects of reduced protein level of GRK2 on insulin-like growth factor 1 receptor (IGF-1R) signaling pathway in human hepatocellular carcinoma (HCC) HepG2 cells. We created a GRK2 knockdown cell line using a lentiviral vector mediated expression of GRK2 specific short hairpin RNA (shRNA). Under IGF-1 stimulation, HepG2 cells with reduced level of GRK2 showed elevated total IGF-1R protein expression as well as tyrosine phosphorylation of receptor. In addition, HepG2 cells with reduced level of GRK2 also demonstrated increased tyrosine phosphorylation of IRS1 at the residue 612 and increased phosphorylation of Akt, indicating a stronger activation of IGF-1R signaling pathway. However, HepG2 cells with reduced level of GRK2 did not display any growth advantage in culture as compared with the scramble control cells. We further detected that reduced level of GRK2 induced a small cell cycle arrest at G2/M phase by enhancing the expression of cyclin A, B1, and E. Our results indicate that GRK2 has contrasting roles on HepG2 cell growth by negatively regulating the IGF-1R signaling pathway and cyclins' expression.

  17. Cytotoxicity and apoptotic effects of tea polyphenol-loaded chitosan nanoparticles on human hepatoma HepG2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Jin [Key Laboratory of Tea Biochemistry and Biotechnology of Ministry of Education and Ministry of Agriculture, Anhui Agricultural University, Hefei 230036 (China); College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Li, Feng [College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Fang, Yong; Yang, Wenjian [College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023 (China); An, Xinxin; Zhao, Liyan; Xin, Zhihong; Cao, Lin [College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Hu, Qiuhui, E-mail: qiuhuihu@njau.edu.cn [College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210023 (China)

    2014-03-01

    Tea polyphenols have strong antioxidant and antitumor activities. However, these health benefits are limited due to their poor in vivo stability and low bioavailability. Chitosan nanoparticles as delivery systems may provide an alternative approach for enhancing bioavailability of poorly absorbed drugs. In this study, tea polyphenol-loaded chitosan nanoparticles have been prepared using two different chitosan biomaterials, and their antitumor effects were evaluated in HepG2 cells, including cell cytotoxicity comparison, cell morphology analysis, cell apoptosis and cell cycle detection. The results indicated that the tea polyphenol-loaded chitosan nanoparticles showed a branch shape and heterogeneous distribution in prepared suspension. MTT assay suggested that tea polyphenol-loaded chitosan nanoparticles could inhibit the proliferation of HepG2 cells, and the cytotoxicity rates were increased gradually and appeared an obvious dose-dependent relationship. Transmission electron microscope images showed that the HepG2 cells treated with tea polyphenol-loaded chitosan nanoparticles exhibited some typical apoptotic features, such as microvilli disappearance, margination of nuclear chromatin, intracytoplasmic vacuoles and the mitochondrial swelling. In addition, the tea polyphenol-loaded chitosan nanoparticles had relatively weak inhibitory effects on HepG2 cancer cells compared with tea polyphenols. Tea polyphenols not only induced cancer cell apoptosis, but also promoted their necrosis. However, tea polyphenol-loaded chitosan nanoparticles exhibited their antitumor effects mainly through inducing cell apoptosis. Our results revealed that the inhibition effects of tea polyphenol-loaded chitosan nanoparticles on tumor cells probably depended on their controlled drug release and effective cell delivery. The chitosan nanoparticles themselves as the delivery carrier showed limited antitumor effects compared with their encapsulated drugs. - Highlights: • Tea polyphenol

  18. Solanine-induced reactive oxygen species inhibit the growth of human hepatocellular carcinoma HepG2 cells.

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    Meng, Xue-Qin; Zhang, Wei; Zhang, Feng; Yin, Sheng-Yong; Xie, Hai-Yang; Zhou, Lin; Zheng, Shu-Sen

    2016-03-01

    The aim of the present study was to investigate the effect of solanine on promoting human hepatocellular carcinoma HepG2 cells to produce reactive oxygen species (ROS), and the molecular mechanisms leading to tumor cell apoptosis. Solanine was administered to HepG2 cells in vitro. A selection of probes targeting various cellular localizations of ROS were used to detect ROS expression using flow cytometry. The expression levels of apoptosis-associated proteins, including apoptosis signal-regulating kinase 1 (ASK1) and thioredoxin binding protein 2 (TBP-2), and proliferation-associated proteins, including histone deacetylase 1 (HDAC1), were detected using western blotting. The percentage of cells undergoing apoptosis was measured using an Annexin V-fluorescein isothiocyanate/propidium iodide assay, and cell morphology was examined using Wright's stain followed by inverted microscopy analysis. ROS detection probes 2',7'-dichlorofluorescin diacetate and dihydrorhodamine 123 identified that abundant ROS, including hydroxyl radical (OH(-)) and hydrogen peroxide (H2O2), were produced in the cytoplasm and mitochondria of the solanine-treated HepG2 cells compared with the control cells (Psolanine treatment compared with the control cells (P>0.05). Western blotting results revealed that solanine upregulated the expression levels of ASK1 and TBP-2 and enhanced their kinase activities, whereas solanine decreased the expression level of the proliferation-associated protein, HDAC1. The cell apoptotic rate was significantly increased (Psolanine-treated HepG2 cells compared with the control cells. (Psolanine induces HepG2 cells to produce ROS, mainly OH(-) and H2O2, in a mitochondria-dependent and -independent manner. In addition, solanine stimulates the expression of ASK1 and TBP-2, and their kinase activities, but inhibits the expression of proliferation-associated proteins, such as HDAC1, thus contributing to HepG2 cell apoptosis.

  19. PTEN enhances G2/M arrest in etoposide-treated MCF‑7 cells through activation of the ATM pathway.

    Science.gov (United States)

    Zhang, Ruopeng; Zhu, Li; Zhang, Lirong; Xu, Anli; Li, Zhengwei; Xu, Yijuan; He, Pei; Wu, Maoqing; Wei, Fengxiang; Wang, Chenhong

    2016-05-01

    As an effective tumor suppressor, phosphatase and tensin homolog (PTEN) has attracted the increased attention of scientists. Recent studies have shown that PTEN plays unique roles in the DNA damage response (DDR) and can interact with the Chk1 pathway. However, little is known about how PTEN contributes to DDR through the ATM-Chk2 pathway. It is well-known that etoposide induces G2/M arrest in a variety of cell lines, including MCF-7 cells. The DNA damage-induced G2/M arrest results from the activation of protein kinase ataxia telangiectasia mutated (ATM), followed by the activation of Chk2 that subsequently inactivates CDC25C, resulting in G2/M arrest. In the present study, we assessed the contribution of PTEN to the etoposide-induced G2/M cell cycle arrest. PTEN was knocked down in MCF-7 cells by specific shRNA, and the effects of PTEN on the ATM-Chk2 pathway were investigated through various approaches. The results showed that knockdown of PTEN strongly antagonized ATM activation in response to etoposide treatment, and thereby reduced the phosphorylation level of ATM substrates, including H2AX, P53 and Chk2. Furthermore, depletion of PTEN reduced the etoposide-induced phosphorylation of CDC25C and strikingly compromised etoposide-induced G2/M arrest in the MCF-7 cells. Altogether, we demonstrated that PTEN plays a unique role in etoposide-induced G2/M arrest by facilitating the activation of the ATM pathway, and PTEN was required for the proper activation of checkpoints in response to DNA damage in MCF-7 cells.

  20. VgrG2 of type VI secretion system 2 of Vibrio parahaemolyticus induces autophagy in macrophages

    Directory of Open Access Journals (Sweden)

    Ying eYu

    2015-03-01

    Full Text Available Type VI secretion system (T6SS is a macromolecular transenvelope machine encoded within the genomes of several proteobacteria species. Vibrio parahaemolyticus contains two putative T6SS systems, VpT6SS1 and VpT6SS2, both contributing to adherence to Caco-2 and/or HeLa cells. However, it remains unknown if these systems are involved in cellular responses. In order to exclude the effects of other virulence factors known to induce cytotoxicity or autophagy, a triple deletion mutant dTTT (with deletion of tdh, and T3SS1 and T3SS2 structural protein genes was used as the parent strain to construct deletion mutants of T6SS genes. The mutant dTTT-icmF2, but not dTTT-icmF1, reduced autophagic response upon 4 h of infection of the macrophage. Further attempt was made to search for the possible effector proteins that might be responsible for direct induction of autophagy by deletion of the genes encoding Hcp2 and VgrG2, two putative translocons of T6SS2 of V. parahaemolyticus. Deletion of either hcp2 or vgrG2 did reduce the autophagic response. However, increased LC3-II lipidation was seen only in the macrophage cells transfected with pVgrG2, but not with pHcp2. Chloroquinine treatment increased accumulation of LC3-II, suggesting that VgrG2 enhanced autophagic flux. The fact that vgrG2 deletion led to reduced level of intracellular cAMP suggests a possible role of cAMP signaling in autophagic responses to the bacterium. We conclude that VgrG2 of V. parahaemolyticus induces autophagy in macrophages.

  1. Chemically induced hepatotoxicity in human stem cell-induced hepatocytes compared with primary hepatocytes and HepG2.

    Science.gov (United States)

    Kang, Seok-Jin; Lee, Hyuk-Mi; Park, Young-Il; Yi, Hee; Lee, Hunjoo; So, ByungJae; Song, Jae-Young; Kang, Hwan-Goo

    2016-10-01

    Stem cell-induced hepatocytes (SC-iHeps) have been suggested as a valuable model for evaluating drug toxicology. Here, human-induced pluripotent stem cells (QIA7) and embryonic stem cells (WA01) were differentiated into hepatocytes, and the hepatotoxic effects of acetaminophen (AAP) and aflatoxin B1 (AFB1) were compared with primary hepatocytes (p-Heps) and HepG2. In a cytotoxicity assay, the IC50 of SC-iHeps was similar to that in p-Heps and HepG2 in the AAP groups but different from that in p-Heps of the AFB1 groups. In a multi-parameter assay, phenotypic changes in mitochondrial membrane potential, calcium influx and oxidative stress were similar between QIA7-iHeps and p-Heps following AAP and AFB1 treatment but relatively low in WA01-iHeps and HepG2. Most hepatic functional markers (hepatocyte-specific genes, albumin/urea secretion, and the CYP450 enzyme activity) were decreased in a dose-dependent manner following AAP and AFB1 treatment in SC-iHeps and p-Heps but not in HepG2. Regarding CYP450 inhibition, the cell viability of SC-iHeps and p-Heps was increased by ketoconazole, a CYP3A4 inhibitor. Collectively, SC-iHeps and p-Heps showed similar cytotoxicity and hepatocyte functional effects for AAP and AFB1 compared with HepG2. Therefore, SC-iHeps have phenotypic characteristics and sensitivity to cytotoxic chemicals that are more similar to p-Heps than to HepG2 cells.

  2. MicroRNA expression in the vildagliptin-treated two- and three-dimensional HepG2 cells.

    Science.gov (United States)

    Yamashita, Yasunari; Asakura, Mitsutoshi; Mitsugi, Ryo; Fujii, Hideaki; Nagai, Kenichiro; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

    2016-06-01

    Vildagliptin is an inhibitor of dipeptidyl peptidase-4 that is used for the treatment of type 2 diabetes mellitus. While vildagliptin can induce hepatic dysfunction in humans, the molecular mechanism has not been determined yet. Recent studies indicated that certain types of microRNA (miRNA) were linking to the development of drug-induced hepatotoxicity. In the present study, therefore, we identified hepatic miRNAs that were highly induced or reduced by the vildagliptin treatment in mice. MiR-222 and miR-877, toxicity-associated miRNAs, were induced 31- and 53-fold, respectively, by vildagliptin in the liver. While a number of miRNAs were significantly regulated by the orally treated vildagliptin in vivo, such regulation was not observed in the vildagliptin-treated HepG2 cells. In addition to the regular two-dimensional (2D) culture, we carried out the three-dimensional (3D) culturing of HepG2 cells. In the 3D-HepG2 cells, a significant reduction of miR-222 was observed compared to the expression level in 2D-HepG2 cells. A slight induction of miR-222 by vildagliptin was observed in the 3D-HepG2 cells, although miR-877 was not induced by vildagliptin even in the 3D-HepG2 cells. Further investigations are needed to overcome the discrepancy in the responsiveness of the miRNA expressions to vildagliptin between in vivo and in vitro. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  3. Carvacrol and rosemary oil at higher concentrations induce apoptosis in human hepatoma HepG2 cells.

    Science.gov (United States)

    Melušová, Martina; Jantová, Soňa; Horváthová, Eva

    2014-12-01

    Natural essential oils are volatile herbal complex compounds which manifest cytotoxic effects on living cells depending on their type and concentration but usually they are not genotoxic. Our previous studies showed that carvacrol (CA) and rosemary essential oil (RO) induced growth inhibition of both human cell lines HepG2 and BHNF-1, with hepatoma HepG2 cells being more sensitive to either compound tested. Cytotoxic concentrations of CA and RO induced the formation of DNA strand breaks. Further ex vivo studies showed that extracts prepared from hepatocytes of CA- and RO-supplemented rats did not increase incision repair activity compared to extracts from liver cells of control animals. Therefore, the aim of this work was to determine the effect of cytotoxic concentrations of CA and RO on the cell cycle and the ability of both natural volatiles to induce DNA fragmentation and apoptotic death of human hepatoma HepG2 cells. These effects were measured after 24 h incubation of HepG2 cells with CA and RO using three independent methods - flow cytometry, internucleosomal DNA fragmentation (electrophoresis) and micronucleus assay. Evaluation of morphological changes and formation of micronuclei in HepG2 cells showed no increase in the number of micronuclei in cells treated by CA and RO compared to control cells. On the other hand, CA and RO induced morphological changes typical for apoptosis in concentration-dependent manner. The presence of necrosis was negligible. Both natural compounds caused shrinking of cytoplasmic membrane and formation of apoptotic bodies. In addition, the highest concentrations of CA and RO induced internucleosomal DNA fragmentation (formation of DNA ladder) in HepG2 cells. Cell cycle analysis revealed the accumulation of cells in the G1 phase, which was accompanied by a reduction in the number of cells in the S phase after 24 h exposure to the substances tested. The cell division was thus slowed down or stopped and this process resulted in cell

  4. [Arginase inhibitor nor-NOHA induces apoptosis and inhibits invasion and migration of HepG2 cells].

    Science.gov (United States)

    Li, Xiangnan; Zhu, Fangyu; He, Yongsong; Luo, Fang

    2017-04-01

    Objective To investigate the cell inhibitory effect of arginase inhibitor nor-NOHA on HepG2 hepatocellular carcinoma cells and related mechanism. Methods CCK-8 assay was used to detect the cell proliferation and flow cytometry to detect the apoptosis of HepG2 cells treated with (0, 0.5, 1.0, 2.0, 3.0) ng/μL nor-NOHA. The protein levels of arginase 1 (Arg1), P53, matrix metalloproteinase-2 (MMP-2), E-cadherin (ECD) were determined by Western blotting. Real time quantitative PCR was employed to examine the changes in the mRNA level of inducible nitric oxide synthase (iNOS). Griess assay was used to measure the concentration of nitric oxide (NO) in HepG2 cells. Transwell(TM) assay and wound-healing assay were performed to evaluate the changes of the cell invasion and migration ability, respectively. Results nor-NOHA inhibited the proliferation and induced the apoptosis of HepG2 cells. It also decreased the expression levels of Arg1 and MMP-2, increased the expression levels of P53 and ECD as well as the production of NO; in addition, nor-NOHA inhibited the invasion and migration of HepG2 cells. Conclusion Nor-NOHA can induce cell apoptosis and inhibit the ability of invasion and migration of HepG2 cells by inhibiting Arg1, which is related with the increase of iNOS expression and the high concentration of NO.

  5. Inhibitory effect of FSLLRY-NH2 on inflammatory responses induced by hydrogen peroxide in HepG2 cells.

    Science.gov (United States)

    Lee, Yeon Joo; Kim, Su Jin; Kwon, Kyoung Wan; Lee, Won Mo; Im, Wi Joon; Sohn, Uy Dong

    2017-07-01

    Proteinase activated receptor 2 (PAR2), which is localized in the GI tract, the respiratory system, and the kidney tubules is a G protein-coupled receptor associated with inflammation, metabolism, and disease. The aim of this study was to explore the role of PAR2 in hydrogen peroxide (H2O2)-induced HepG2 cells by using FSLLRY-NH2 a PAR2 antagonist. H2O2 treatment resulted in induction of PAR2 in esophageal, gastric, and liver cells, with the most robust response being in HepG2 cells. Furthermore, this effect was dose-dependent in HepG2 cells. Treatment with H2O2 at concentrations above 400 μM for 24 h also reduced HepG2 cell viability. H2O2 treatment increased both the protein and mRNA levels of IL-1β, IL-8, and TNF-α, as well as those of SAPK/JNK. The increased levels of these pro-inflammatory genes and SAPK/JNK induced by H2O2 were attenuated in a dose-dependent manner when cells were co-treated with H2O2 and FSLLRY-NH2. In summary, the PAR2 antagonist peptide, FSLLRY-NH2, reduces the level of the pro-inflammatory genes IL-8, IL-1β, and TNF-α induced by H2O2, through the SAPK/JNK pathways in HepG2 cells. These data suggest that a PAR2 antagonist could be an anti-inflammatory agent in HepG2 cells.

  6. Restoration of miR-20a expression suppresses cell proliferation, migration, and invasion in HepG2 cells.

    Science.gov (United States)

    Chen, Guang Shun; Zhou, Ning; Li, Jie-Qun; Li, Ting; Zhang, Zhong-Qiang; Si, Zhong-Zhou

    2016-01-01

    To study microRNA (miR)-20a expression in hepatocellular carcinoma (HCC) and its effects on the proliferation, migration, and invasion of HepG2. The real-time polymerase chain reaction was used to detect the expression of miR-20a in HCC tissue and normal tissue, as well as in HCC cell lines and normal liver cells. miR-20a mimic and miR negative control (NC) were transfected into HepG2 cells. MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay was used to detect cell proliferation. Annexin fluorescein isothiocyanate/propidium iodide assay was run to examine the early apoptosis of cells. Transwell chamber assay was carried out to investigate the cell invasion and migration abilities. miR-20a was lowly expressed both in HCC tissues and HCC cell lines. After transfection of exogenous miR-20 mimics, miR-20a expression in HepG2 cells was significantly increased by 61.29% compared to the blank group (PHepG2 cells in the miR-20a mimics group was significantly inhibited, and optical density values during the 36-96 hour time period were dramatically decreased compared to the blank group (PHepG2 cells, the number of cell migration and invasion in the small interfering (si)-CCND1 group were 0.444 and 0.435 times that of the si-NC group (PHepG2 cells, and is therefore promising as a new molecular target for diagnosis and therapy of HCC.

  7. Relationship of HepG2 cell sensitivity to continuous low dose-rate irradiation with ATM phosphorylation

    Institute of Scientific and Technical Information of China (English)

    Quelin Mei; Jianyong Yang; Duanming Du; Zaizhong Cheng; Pengcheng liu

    2008-01-01

    Objective: To investigate the change of ATM phosphorylation in HepG2 cells and its effect on HepG2 cell survival under a continuous low dose-rate irradiation.Methods: HepG2 cells were exposed to equivalent doses of irradiation delivered at either a continuous low dose-rate (7.76 cGy/h) or a high dose-rate (4500 cGy/h).The ATM phosphorylated proteins and surviving fraction of HepG2 cell after low dose-rate irradiation were compared with that after equivalent doses of high dose-rate irradiation.Results: The phosphorylation of ATM protein was maximal at 0.5 Gy irradiation delivered at either a high dose-rate or a continuous low dose-rate.As the radiation dose increased, the phosphorylation of ATM protein decreased under continuous low dose-rate irradiation.However, the phosphorylation of ATM protein was remained stable under high dose-rate irradiation.When the phosphorylation of ATM protein under continuous low dose-rate irradiation was equal to that under high dose-rate irradiation, there was no significant difference in the surviving fraction of HepG2 cells between two ir-radiation methods (P>0.05).When the phosphorylation of ATM protein significantly decreased after continuous low dose-rate irradiation compared with that after high dose-rate irradiation, increased amounts of cell killing was found in low dose-rate irradiation (P<0.01).Conclusion: Continuous low dose-rate irradiation increases HepG2 cells radiosensitivity compared with high dose-rate irradiation.The increased amounts of cell killing following continuous low dose-rate exposures are associated with reduced ATM phosphorylated protein.

  8. Salmonella typhimurium strain SL7207 induces apoptosis and inhibits the growth of HepG2 hepatoma cells in vitro and in vivo

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    Baowei Li

    2012-12-01

    Full Text Available Salmonella typhimurium is probably most extensively studied tumor-targeting bacteria and SL7207 is one of its attenuated strains. SL7207 was first made for bacterial vaccine development and its therapeutic efficacy and safety for hepatocellular carcinoma has not been characterized. In this study, the inhibitory ability of SL7207-lux on human hepatoma HepG2 cells was tested in vitro and in vivo. A bacterial luminescent gene cluster (lux CDABE was transfected into SL7207 to better monitor the invasion of the bacteria. The results show that SL7207-lux can rapidly enter HepG2 cells and localize in the cytoplasm. This invasion represses cell proliferation and induces apoptosis. In vivo real-time invasion studies showed that the bacteria gradually accumulate in the tumor. This enrichment was confirmed by anatomic observation at 5 days after inoculation. About 40% of tumor growth was inhibited by SL7207-lux at 34 days post-treatment without significant loss of body weight. The area of necrosis of tumor tissue was clearly increased in the treated group. Bacterial quantification showed that the number of colony-forming units per gram of bacteria within tumor tissue was approximately 1000-fold higher than that of liver and spleen. These data suggest that attenuated S. typhimurium strain SL7207 has potential for the treatment of cancers.

  9. Heterologous expression of human cytochrome P450 2E1 in HepG2 cell line

    Institute of Scientific and Technical Information of China (English)

    Jian Zhuge; Ye Luo; Ying-Nian Yu

    2003-01-01

    AIM: Human cytochrome P-450 2E1 (CYP2E1) takes part in the biotransformation of ethanol, acetone, many smallmolecule substrates and volatile anesthetics. CYP2E1 is involved in chemical activation of many carcinogens,procarcinogens, and toxicants. To assess the metabolic and toxicological characteristics of CYP2E1, we cloned CYP2E1 cDNA and established a HepG2 cell line stably expressing recombinant CYP 2E1.METHODS: Human CYP2E1 cDNA was amplified with reverse transcription-polymerase chain reaction (RT-PCR)from total RNAs extracted from human liver and cloned into pGEM-T vector. The cDNA segment was identified by DNA sequencing and subcloned into a mammalian expression vector pREP9. A transgenic cell line was established by transfecting the recombinant plasmid of pREP9-CYP2E1 to HepG2 cells. The expression of CYP2E1 mRNA was validated by RT-PCR. The enzyme activity of CYP2E1 catalyzing oxidation of 4-nitrophenol in postmitochondrial supernate (S9) fraction of the cells was determined by spectrophotometry. The metabolic activation of HepG2-CYP2E1 cells was assayed by N-nitrosodiethylamine (NDEA)cytotoxicity and micronucleus test.RESULTS: The cloned CYP2E1 cDNA segment was identical to that reported by Umeno et al(GenBank access No.J02843). HepG2-CYP2E1 cells expressed CYP2E1 mRNA and had 4-nitrophenol hydroxylase activity (0.162±0.025nmol.min-1.mg-1 S9 protein), which were undetectable in parent HepG2 cells. HepG2-CYP2E1 cells increased the cytotoxicity and micronucleus rate of NDEA in comparison with those of HepG2 cells.CONCLUSION: The cDNA of human CYP2E1 can be successfully cloned, and a cell line, HepG2-CYP2E1, which can efficiently express mRNA and has CYP2E1 activity, is established. The cell line is useful for testing the cytotoxicity,mutagenicity and metabolism of xenobiotics, which may possibly be activated or metabolized by CYP2E1.

  10. Time- and concentration-dependent effects of resveratrol in HL-60 and HepG2 cells

    DEFF Research Database (Denmark)

    Stervbo, Ulrik; Vang, Ole; Bonnesen, Christine

    2006-01-01

    , an increase in nuclear size and granularity was observed in the G1 and S phases of HL-60 treated and HepG2-treated cells. Apoptosis was also stimulated by resveratrol in a concentration-dependent manner in HL-60 and HepG2 cells. In conclusion, resveratrol inhibits cell proliferation in a concentration......- and time-dependent manner by interfering with different stages of the cell cycle. Furthermore, resveratrol treatment causes stimulation of apoptosis as well as an increase in nuclear size and granularity....

  11. Selective cytotoxicity of PAMAM G5 core–PAMAM G2.5 shell tecto-dendrimers on melanoma cells

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    Schilrreff P

    2012-07-01

    Full Text Available Priscila Schilrreff,1 Cecilia Mundiña-Weilenmann,2 Eder Lilia Romero,1 Maria Jose Morilla11Programa de Nanomedicinas, Universidad Nacional de Quilmes, Buenos Aires, Argentina; 2Centro de Investigaciones Cardiovasculares, Universidad Nacional de La Plata, La Plata, ArgentinaBackground: The controlled introduction of covalent linkages between dendrimer building blocks leads to polymers of higher architectural order known as tecto-dendrimers. Because of the few simple steps involved in their synthesis, tecto-dendrimers could expand the portfolio of structures beyond commercial dendrimers, due to the absence of synthetic drawbacks (large number of reaction steps, excessive monomer loading, and lengthy chromatographic separations and structural constraints of high-generation dendrimers (reduction of good monodispersity and ideal dendritic construction due to de Gennes dense-packing phenomenon. However, the biomedical uses of tecto-dendrimers remain unexplored. In this work, after synthesizing saturated shell core–shell tecto-dendrimers using amine-terminated polyamidoamine (PAMAM generation 5 (G5 as core and carboxyl-terminated PAMAM G2.5 as shell (G5G2.5 tecto-dendrimers, we surveyed for the first time the main features of their interaction with epithelial cells.Methods: Structural characterization of G5G2.5 was performed by polyacrylamide gel electrophoresis, matrix-assisted laser desorption time-of-flight mass spectrometry, and microscopic techniques; their hydrodynamic size and Z-potential was also determined. Cellular uptake by human epidermal keratinocytes, colon adenocarcinoma, and epidermal melanoma (SK-Mel-28 cells was determined by flow cytometry. Cytotoxicity was determined by mitochondrial activity, lactate dehydrogenase release, glutathione depletion, and apoptosis/necrosis measurement.Results: The resultant 60%–67% saturated shell, 87,000-dalton G5G2.5 (mean molecular weight interacte